Tuesday, November 26, 2019
Experience Psychology, 3rd edition Essays (720 words) - Psychology
Experience Psychology, 3rd edition Essays (720 words) - Psychology Experience Psychology, 3rd edition Chapter 5, Learning Vocabulary, Key Terms Acquisition: The initial learning of the connection between the unconditioned stimulus and the conditioned stimulus when these two stimuli are paired. Applied behavior analysis (or behavior modification): The use of operant conditioning principles to change human behavior. Associative learning: Learning that occurs when an organism makes a connection, or an association between two events. Aversive conditioning: A form of treatment that consists of repeated pairings of a stimulus with a very unpleasant stimulus. Avoidance learning: An organism's learning that it can altogether avoid a negative stimulus by making a particular response. Behaviorism: A theory of learning that focuses solely on observable behaviors, discounting the importance of such mental activity as thinking, wishing, and hoping. Classical conditioning: Learning process in which a neutral stimulus becomes associated with an innately meaningful stimulus and acquires the capacity to elicit a similar response. Conditioned response (CR): The learned response to the conditioned stimulus that occurs after a conditioned stimulus-unconditioned stimulus pairing. Conditioned stimulus (CS): A previously neutral stimulus that eventually elicits a conditioned response after being paired with the unconditioned stimulus. Counter-conditioning: A classical conditioning procedure for changing the relationship between a conditioned stimulus and its conditioned response. Discrimination (operant conditioning): Responding appropriately to stimuli that signal that a behavior will or will not be reinforced. Extinction (operant conditioning): Decreases in the frequency of a behavior when the behavior is no longer reinforced. Generalization (operant conditioning): Performing a reinforced behavior in a different situation. Habituation: Decreased responsiveness to a stimulus after repeated presentations. Insight learning: A form of problem solving in which the organism develops a sudden insight or understanding of a problem's solution. Instinctive drift: The tendency of animals to revert to instinctive behavior that interferes with learning. Latent learning or implicit learning: Unreinforced learning that is not immediately reflected in behavior. Law of effect: Thorndike's law stating that behaviors followed by positive outcomes are strengthened by positive outcomes and that behaviors followed by negative outcomes are weakened. Learned helplessness: Through experience with unavoidable aversive stimuli, an organism learns that it has no control over negative outcomes. Learning: A systematic, relatively permanent change in behavior that occurs through experience. Negative punishment: The removal of a stimulus following a given behavior in order to decrease the frequency of that behavior. Negative reinforcement: The removal of a stimulus following a given behavior in order to increase the frequency of that behavior. Observational learning: Learning that occurs through observing and imitating another's behavior. Operant conditioning (instrumental conditioning): A form of associative learning in which the consequences of a behavior change alters the probability of the behavior's occurrence. Positive punishment: The presentation of a stimulus following a given behavior in order to decrease the frequency of that behavior. Positive reinforcement: The presentation of a stimulus following a given behavior in order to increase the frequency of that behavior. Preparedness: The species-specific biological predisposition to learn in certain ways but not others. Primary reinforcer: A reinforcer that is innately satisfying: one that does not take any learning on the organism's part to make it pleasurable. Punishment: A consequence that decreases the likelihood that a behavior will occur. Reinforcement: The process by which a stimulus or an event (a reinforcer) following a particular behavior increases the probability the behavior will happen again. Schedules of reinforcement: Specific patterns that determine when a behavior will be reinforced. Secondary reinforcer: A reinforcer that acquires its positive value through an organism's experience: a secondary reinforcer is a learned or conditioned reinforcer. Shaping: Rewarding successive approximations of a desired behavior. Spontaneous recovery: The process in classical conditioning by which a conditioned response can recur after a time delay with further conditioning. Unconditioned response (UR): An unlearned reaction that is automatically elicited by the unconditioned stimulus. Unconditioned stimulus (US): A stimulus that produces a response without prior learning.
Friday, November 22, 2019
What Really Is The Best Headline Length
What Really Is The Best Headline Length How long should my headline be? Youve asked yourself this, and with good reason. In the content marketing world, a lot ofà attention has been given to the headline of your blog post in recent years. Theres so much headline information out there, so many dos and donts, so many great tips that youre drowning in advice and you have no idea of what to actually do. You want a definitive answer in the form of a number or at least a firm set of guidelines. You dont want to hearà it depends. The truth is, it does depend. Sort of. It depends on what you want your headline to do. Do you know what you want from your headline? What Really Is The Best #Headline Length? #blogging via @JulieNeidlinger Write The Bestà Headlines With Aà Free Headline Analyzer The headline analyzerà will help you: Use headline types that get the most traction for social shares, traffic, and search engine ranking. Make sure you have the right word balance to write readable headlines that command attention. See the bestà word and character length for search engines like Google and email subject lines, while also seeingà how your readers will scan your headlines. Try The Free Headline Analyzer Now How To Write The Best Headlines The Old School Way There are two schools of thought when it comes to headlines. Traditionally, headlines should be, according to Jakob Nielsen: Short, typically 5 words or less. People dont read very much online. Information-rich. The headline should summarize the article. Starts with keywords. People tend to scan, and read the first words most of all. Understandable, even out of context. Headlines often appear on their own, without articles. Especially in social media and search engine results. Predictable and match reader expectations. Dont frustrate your reader. They should get what they expect when they click. Nielsens shorter headlines arent the label variety. Label headlines are those which are short, but not terribly information rich. For example, a Nielsen headline might be Speeding Car Crashes Into Wall while an uninformative label-type headline might read Speeding Car. I Want My Headline To Perform Well On Social Media The second school of thought, however, is what we tend to see online now. And it seems to beà the exact opposite of what Nielsen says. A headline that performs well on social media is one that people share a lot, and click through a fair amount. But mostly share. The headline is often shared as much as the people sharing it will read. This is a unique situation in headline history. Instead of being helpful in the traditional sense (as described above), headlines are now meant toà invoke curiosity and capture clicks. Write #headlines to invoke curiosity and capture clicks. via @JulieNeidlingerThis is particularly important on social media, where news feeds are quickly cycling through, competition with other headlines is fierce, and you have to pull out all stops to get someone to notice. Long, rambling, and sometimes bordering on bizarre. Headlines now are often quite long and almost a story unto themselves. Though that is shifting somewhat from 2014 (the year of Upworthy-styled headlines), headlines still maintain a longer approach than Nielsen might recommend. Emotion-rich. What the article is about doesnt matter. Emotion does. Keywords are sparse. Few keywords, with more attention given to emotional subtexts. Not much context. Without the article, the headline is a worm on a hook and little more. Rely on shock/emotion/curiosity factor. Readers dont know what to expect, and thats why they click. How does that speeding car headline read for the social media age? How about 5 Reasons You Should Fear That Speeding Car. The social messages that accompany your blog posts wont necessarily be your headline. Youll probably customize them for repeated shares. But if you do rely on your blog post headline to be the body of the social message, then the ideal social message length will matter for your headlines. Buffers Kevan Lee has written a seriously comprehensive blog post about the ideal lengths of just about anything you could put online. Its packed with information on the length of just about everything, but check out what he discovered for the most popular social networks: Twitter: 71ââ¬â100 characters Facebook: 40 characters Google+: 60 characters LinkedIn:à 80ââ¬â120 characters Depending upon which network you lean most heavily or get the most traction, you should consider making your headline fit the ideal length for that socialà network. Within those character ranges, remember the importance of emotions in a headline that does well on social media. Emotional headlines, with specific trigger words, get shared more on social media. I Want My Headline To Do Well In Email Just like social media, you have the ability to customize your emails so that you rework how your headlines appear in the subject lines. But not everyone does. Sometimes the work you put into finding that perfectà headline can carry right on through to your email subject line. So how long should they be? MailChimp, the popular email provider, has stated that it doesnt really matter how long your subject lines are. Last year, we carried out our own tests on how our email subject lines fared. We found that an email subject line with around 50 characters fared the best. The conclusion? Find out what works for you by testing if you dont believe either MailChimp or our results. As you test your headlines in your email to determine what works, remember the difference between open rates and click-through rates. Open rates are not the same as click-through rates. An open rate is the percentage of total recipients that opened the email. In some email software, just by opening their inbox they open emails. The click-through rate is the percentage of those who opened and then clicked at least once. Aim for a high click-through rate as the basis of what a successful headline does, not just an open rate.
Thursday, November 21, 2019
Gender and the Media Essay Example | Topics and Well Written Essays - 1500 words
Gender and the Media - Essay Example This paper stresses that a good number of women lived in fear of their sexuality since this was one matter not examined for subtext and submerged meanings. For instance, majority of Inuit people of Canada live in isolated arctic communities that make it impossible for them to access consumer goods and medical services. Femininity made the women especially in the eighteenth century fall victims of housing crisis. In fact, the problematic housing condition leaves the then urban woman with quite insecure situations of living. To some readers more familiar with femininity politics and with issues of recognition, the politics may appear unusual or even odd. The author says that some independent films have empowered featured women as cultural product interpreters. Hook pioneered a research field in black women readers of culture that put together the cultural studies and the African American studies. This was possible through the techniques of interviewing and textual interpretation based on criticism. The researchââ¬â¢s intentions were to join the two studies and eradicate criticism. This report makes a conclusion that nobody hates looking at womenââ¬â¢s funny character in movies. Something that Caroline well put across. The conditions of watching Mr.mom a movie in the cinema gives authority to a voyeuristic spectatorship. All spectators are chirping characters taking pleasure and watching others while they remain unseen. In other fields, feminists have identified voyeurism as conflict that is because of gender. The chirping character is most often a man-watching female without her knowledge. As a result, for Stuart Hall insights, Hooks and other critics bring up many questions about the response of women regarding the visual arts in the modern world, which includes photography and film. The black looks say a lot about race and representation. Basing this on Hookââ¬â¢s argument, critical spectatorship of the black female only comes up when an individual woman resist becoming the subject of looking and knowing or in other words image and story. Their resista nce to identifying themselves with settings of gender and race tender for their consumption. Men critic their positive decisions and creates opposite texts and interpretations. This makes the black woman lack freedom to make decisions on her own since her wish means end of career. Hook says that any black woman featured on Hollywoodââ¬â¢s films creates either a good image or a bad image to her race (McWilliams, 183). Some independent films have empowered featured women as cultural product interpreters. Hook pioneered a research field in black women readers of culture that put together the cultural studies and the African American studies. This was possible through the techniques of interviewing and textual interpretation based on criticism. The researchââ¬â¢s intentions were to join the two studies and eradicate criticism. After a series of lengthy interviews, she came up with conclusive answers that the black women were not happy with the image instilled on them especially on the interpretations of the press, which contrasted theirs. Her work was difficult and a historical moment is the only thing that helps. Women interpretive images from the positions they held dominated the constructions of gender and race. Hook paid extra attention to images of gender and race gotten from the gallery and the museum. At the same time, many scholars paid attention to the images intersection depicting gender and race. One of the scholars did examinations on two images totally unrelated. The images were that of the Hottentots women and that of a prostitute. There is no way the two could ever be in the same relationship. Prostitution is a very bad image in the society and no body likes the association. Names used to refer to the black race were very off putting and mean. Some of these names included lesbians and gays. Nothing good according to Hook comes from a black woman. When you combine power, gender and race, a black woman has nothing more to shelter under. They are helpless and the only thing they do is to try to survive. The mechanisms for survival are minimal as the only place their voice has priority is through the media. Although there are no reasons to justify this, the important part is Jack argument of the threat content cinematically. The womanââ¬â¢s figure according to Jack provides means of compensation because she becomes the reason for the menââ¬â¢s gaze and to whom they direct probe, look at, control and
Tuesday, November 19, 2019
The Future of Education in US and Saudi Arabia Essay
The Future of Education in US and Saudi Arabia - Essay Example According to the research findings the revolution in the education sector will also result in an overall information symmetry to the residents of both countries and at large the world. The education infrastructure will also get upgraded and the funds spend on the acquisition teaching staff decline. It will become a cost cutting strategy as the education sector has over time utilized large amounts of capital that could have got utilized in developing other sectors. The overall adoption of technology in the education sector will eventually result in a declined rate of illiteracy and ignorance levels as learning shall become a progressive exercise.From the discussion it is clear thatà the initiation of formal education dates back to the 19th century when people saw the need of adopting a formalized educational system as opposed to the informal. The future of the education will heavily relay on the adoption of formalized systems of impacting knowledge to the students. The development a genda of the education sector will heavily rely on the methods of overcoming the barriers that have for long hindered the development and establishment of formalized education in both US and Saudi Arabia. The aim is to ensure that learning can take place anyplace anytime so long as there learner has a willingness to learn. The idea of students going to school for classes shall change and become history. It is so as classroom learning will no longer be taking place and if it happens to be shall be made for the young generation only.
Sunday, November 17, 2019
War and the pity of war Essay Example for Free
War and the pity of war Essay Owens use of the word pity in this quotation immediately reveals his opinion of war. In the dictionary pity is defined as sorrow and compassion aroused by anothers condition or something to be regretted. Owen incorporates both of these definitions into his poetry when describing war. I intend to concentrate on the various devices Owen uses to convey his opinion of War in three of his poems, Disabled, Mental Cases and Exposure. The titles of two of his poems, Disabled and Mental Cases tell of the effect that Owen believes the war to have on those who fought in it. He believes that it has a detrimental, crippling effect on such people and that many lose their sanity because of it. Owens poem Mental Cases focuses on those people who survive the war but are confined to a mental asylum because of it. He uses words such as misery, tormented, hideous and madness to describe the mental state of these men. Owens poems give the distinct impression that the men involved in it are constantly plagued by memories of those that they have killed. Owen writes effectively and truthfully about this because he fought in World War One himself. In Exposure the soldiers imagine the bodies of their comrades impaled upon wire: we hear mad gusts tugging on the wire, Like twitching agonies of men among its brambles. This shows that their thoughts always return to those who have died in the War. Owens use of the word mad is an attack on the cruelty and irrationality of War. In Mental Cases the survivors are described as purgatorial shadows. Purgatory was considered to be a place somewhere between heaven and hell, a place of indecision, an eternal hell. These people in the poem are experiencing a living hell. In fact, later in the poem Owen says that people who walk amongst these tortured souls feel as though they are walking hell. The description of the mental patients as shadows indicates that the War has turned them into apparitions who barely brush the boundaries of existence. These are men whose minds the Dead have ravished. This shows that the men are in fact being tortured by the memory of those they have killed in the war. In the quotation the dead people have been personified. This makes them seem more like one body rather than many individual men. By depriving the dead of their identity the mental cases are able to lessen some of the guilt that they feel, and the extent of the carnage incomparable is easier for them to comprehend. Having ended the line preceding it with a question, Owen starts the above line with a hyphen, to give the effect that he is answering the question. In the first paragraph of Mental Cases the identity of the men is repeatedly questioned. The above line provides these men with an identity Owens attempt to pay homage to all those who served in the War. The lack of appreciation for those men involved in the war is something that Owen often incorporates into his poems. For example in Disabled the young man is not commended by anyone other than a religious figure who thanked him for his efforts in the War. The word thanked is printed in italics to convey the mans (and therefore Owens) bitterness at this lack of appreciation. Similarly in Exposure it is said that those soldiers lucky enough to return home soon find that their families and friends have moved on without them: on us the doors are closed. This shows that Owen believes that the War cuts every man off from the rest of the world. The men have experienced something so terrible that no one else can sympathise with them, including their families. It should be clear to anyone reading Owens poems that he associates the War with pain and suffering. In Exposure he suggests that the impact of the War is so huge that even nature begins to become cruel. Owens association of the unkind weather to the cruelty of the War could be described as pathetic fallacy. The merciless iced east winds that knive us Owens use of the word merciless is typical of the vocabulary he commonly uses to describe a War that he views as callous and unrelenting. He says that the wind knives the soldiers, which is a violent human action, and he later describes it as mad. Such description is more suited to the description of a living thing and therefore Owen almost personifies the wind. In Disabled Owen dwells on the debilitating effect the war has on a young boy. He is changed from a handsome man for whose face an artist was silly into an insecure old man who will never feel again how slim girls waists are. The poem focuses on this mans life before and after the war in order to make the change in his life from good to bad seem more dramatic. The picture that is conjured in the readers mind by Owens poetry is lacking in colour. The image formed in the readers mind are grey bland and empty, not at all alive or vibrant. They therefore can represent the lives of those involved in the war. In Disabled the mans life before the war is described using colourful words. Trees are light blue and his blood is purple (the colour purple is considered to be prestigious, and therefore may be an indication that courage coursed through his veins before the war ruined him). After the war, his world becomes dull and grey. He wears a ghastly suit of grey (note the use of the word ghastly to represent the horror of the War). In Exposure a personification of dawn attacks the ranks on shivering ranks of grey men. This lack of colour is explained in Disabled, when Owen states: hes lost his colour very far from here, Owen explains that war strips the colour and life from all those involved in it. Owen often uses alliteration in his poetry to add effect. For example in Exposure: Worried by silence, sentries whisper, curious, nervous. The repeated s sound in this line makes the reader feel that he/she can hear whispering. In Mental Cases the line: Rucked too thick for these mens extrication uses a lot of harsh ck sounds. The line is referring to the huge amount of human squander, and therefore such harsh sounds make the mood increasingly dramatic. Owens use of the word squander shows that he views the death of so many men in the war as wasteful and pointless. Similarly in Disabled the young man says that he threw away his knees. By using the word threw Owen shows that the man acted recklessly, wasting the gifts that he would not appreciate until he was without them. In Exposure there are many questions asked that Owen does not answer in the poem. For example What are we doing here? and -Is that why we are dying? The men in the poem are questioning the point of their fighting in the war. The fact that they are so unsure of their existence is pitiful. The rhyming and rhythm in Owens poetry is not always regular. Because it is satisfying for people to hear an perfectly rhyming poem with a regular beat, Owen makes sure that his work is not satisfying to the human ear. The almost disjointed manner in which many lines read makes the poems disconcerting, thus the war is less enjoyable to read about. Owen also achieves this dissatisfaction by varying the structure and length of the passages in his poems. For example in Disabled the length of each passage varies greatly. More time is spent reflecting on the young mans past, which gives the reader the impression that the man is regretful. The paragraphs concerning his present life are relatively brief and to the point, showing the extent to which his life has been cut up by the War. Owen uses para rhyming in Exposure, keeping the constanents of the rhyming words the same but changing the vowel sound. This technique is not satisfying to the human ear and therefore ensures that the reader feels troubled about what he/she is reading, i.e. the war. The rhyming and rhythm of Mental Cases is more regular. Therefore in order to ensure that his reader does not feel comfortable with what he/she is reading, Owen makes use of stronger, more shocking imagery such as leering skulls and men wading sloughs of blood. Owen also disrupts the order of the poem to some extent by starting lines with hyphens and punctuating the piece with questions such as but who these hellish? Owens message to his readers is that war is horrific. However the propaganda for the First World War during Owens time did not reveal such horrors, therefore many people joined for the wrong reasons. In Disabled the young man: thought of jewelled hilts For daggers in plaid socks. Owen wanted to reveal this to be a misconception of war. To me, Owens poems convey a strong sense of regret. In Disabled the young man ruins his life simply to please the giddy jilts. Because of this the man is eventually forced to: take whatever pity they may dole. Owens use of the word dole seems as though the people doling the pity are insincere, and it makes the man sound bitter and resentful. It is possible that the young man in this poem is a figurehead of Owen himself, who spent time in Craiglockhart War Hospital having been severely injured during the war. The above quotation uses the one word that Owen directly associates with war: pity. In Exposure the soldiers constantly ask questions, almost as though they are vulnerable (exposed) and in need of guidance. They are despairing and definitely regretful: We cringe in holes. This animal-like action reveals the soldiers shame at what they have been reduced to. They do not try to glorify or even justify their actions. They are forced to accept them. In Mental Cases there is no regret expressed on behalf of the mental patients until the very end of the poem. Throughout the poem the mental patients are described as purgatorial shadows and do not appear to have the state of mind to by conscious of their surroundings. However at they end they are described as: Pawing [those] who dealt them war and madness. This shows that they resent those people who caused them to end up as mental cases.
Thursday, November 14, 2019
The Tragic Cliff Essay -- Descriptive Essay Examples
The Tragic Cliff à Everyone needs a place to escape the everyday complications of life. Life has its ups and downs and we all learn to deal with them in different ways. Some people use exercise to release stress while others find places to hide from the stress for short periods of time. à I found a place of relaxation hundreds of feet above everyone looking down. Right outside of town there is a cliff that overlooks the downtown area. There I feel as though I am above everyone and nothing could touch me. I feel comfort just knowing I can observe thousands of people below me, like looking at little ants through a microscope, yet no one can see me. Trees and bushes hover over me like a blanket giving me shelter. It's almost like playing God. à Although I haven't been to the cliff in quite a while, do to being so busy, I still remember the peace I received that I could never find. To me, the cliff was a place of memories, innocence, and free energy. In nature there aren't any rules, regulations, or right or wrong answers. It's a place of freedom! &nbs...
Tuesday, November 12, 2019
Vietnam Economy
nom Economic Vietnam has during the last two decades developed into a dynamic and fast growing market ââ¬â also in automobile industry. Economic reforms, membership of WTO since 2007 and an impressive number of foreign investments, the notable increase in GDP, in peopleââ¬â¢s demand for high quality product and the almost-zero of the domestic automobile industry have led Vietnam to become the potential market for Volkswagen. The global crisis led to a temporary slowdown of Vietnamââ¬â¢s fast economic growth, but growth is back on track with 6. % growth in 2010 and more than 7% per year expected in 2011-2015. Table 1: Vietnamââ¬â¢ GDP real growth rate (%) [pic] Source: Source: General Statistics Office of Vietnam The rate of economic growth has during the last decade amounted to 7-9% per year, amongst the highest recorded growth rates in the world. The GDP per capita is USD 1160 (2010), and an increasing number of Vietnamââ¬â¢s 87 million inhabitants demand consumer pr oducts of higher quality. Table 2: Vietnamââ¬â¢s GDP per capital (US$) [pic] Source: General Statistics Office of Vietnam However, the average income in Vietnam is still fairly low in comparison with the company price (aboutâ⬠¦Ã¢â¬ ¦Ã¢â¬ ¦Ã¢â¬ ¦.. cai nay lay so lieu ben product nhe, to k tim duoc). According to ââ¬Å"Background note of Vietnamâ⬠recorded by U. S Department of State in http://www. state. gov, Vietnamââ¬â¢s per capita income in 2010 was just $1,168 one person per year. Whereas, imported cars in Vietnam have to suffer upto 3 kinds of duty, including: Import Duty, Extra Duty, and Value Added Tax. Regardless of how strict Vietnam taxation policy is, the accession agreement which was compulsory for Vietnam to become WTOââ¬â¢s member in 2007 obliged Vietnam to lower its import tariffs and to welcome foreign investments in most commercial sectors of the economy. Certain sectors are partly protected against foreign competition in an interim period, but from 2012 respectively 2014 all sectors of the economy must welcome foreign goods and services as well as investors on an equal footing with local companies and investors. Therefore, we totally hope that in the upcoming period, such a 200% tariff for exported cars will not exist. Vietnam automobile market is not that big but it sees a potential signal. According to General Statistics Office of Vietnam [ http://www. gso. gov. vn/default. aspx? tabid=393&idmid=3&ItemID=11605 to k biet trich nguon ntn cho dung voi Harvard form ca T_T], the demand for imported cars, especially types of fewer than 9 seats which makes of approximately 70% in total, keeps increasing remarkably, from 21279 units in 2005 to 51059 in 2008 and reach the number of about 80410 in the last year. Whereas the domestic automobile industry seems to not improve at all. Until now, the domestic company still can not produce even one car. Vietnamà now has 10 automobile JVs including one 100 % foreign-owned enterprise (GM Daewoo), one domestic manufacturer (Truong Hai). The manufacturers make vehicles of 17 world brands: Fiat, Sangyong, PMC, Mazda, Kia, Chevrolet, Daewoo, Mitsubishi, Mercedes Benz, Suzuki,à Toyota, Isuzu, Ford, Hino, Hyundai (trucks, bus), Chery and Honda. In this moment, Volkswagen is one of more then 10 brands having distribution channel in. These brands include BMW (Euro Auto), Audi, Porsche (PSC), Hyundai (Thanh Cong), Lifan (Bao Toan), Chrysler (IC Auto), Subaru (MIV), Dong Feng,à à MAN (VMC) and Fiat ââ¬â Alfa Romeo (Mekong Auto), who are all considerable competitors. It is a great opportunity for the company to dominate Vietnam market but also a challenge when our products are almost kind of high quality with high price.
Saturday, November 9, 2019
First Steps Film Assignment Essay
The following assignment is based on the film ââ¬Å"Becoming Human Episode 1: First Steps.â⬠You may access the film in the following ways: 1. It is available for free on the PBS website at the following address: http://video.pbs.org/video/1312522241/ 2. It is available instantly through Netflix (where you may temporarily set up a free account for a few weeks if you are not a member). Please use complete sentences to answer the following questions and type your answers on this form. You should submit this assignment to the ââ¬Å"First Stepsâ⬠dropbox using the ââ¬Å"Assignmentsâ⬠tab by Sun 4/1 at 11:59 P.M. Please submit this file as a .doc, .docx, .rtf, or .pdf file. Please do not use the ââ¬Å".pagesâ⬠extension because PCs cannot open it. 1. Where is the Afar located? Afar is one of the nine Regional States of Ethiopia and is located in north eastern Africa. It is a part of the great rift valley (deep cut in earth where geological forces are ripping Africa apart). 2. How did researchers figure out how old the ââ¬Å"Selamâ⬠fossil was? Clues to the age of the fossil came from key features in the landscape; such as the white bands of volcanic ash that dated 3.4 million years ago. If the white bands of volcanic ash are 3.4 million years old then the fossil must be younger because it was found above it. Therefore, the fossil was approximately 3.3 million years old. 3. How did researchers figure out how old the fossil child Selam was when she died? How old was she? Researchers looked at Selamââ¬â¢s teeth in order to find out how old she was when she died. They did not look at the baby teeth that were visible in her jaw; they looked her adult teeth that were growing inside the bone. From that observation researchers know Selam died when she was three years old. 4. What are the human-like components of the ââ¬Å"Lucyâ⬠skeleton? What are the ape-like components? Lucky had both human-like and ape-like components. From the waist down lucy was like humans and from the waist up she was like apes. She walked upright like humans and her pelvis bone resembled those of a human. Lucyââ¬â¢s greater trochanter was short and human-like. Her skeleton showed evidence of small skull capacity similar to apes. 5. What was the ancient environment of the australopithecines like? How does it change by 3-4 million years ago? Researchers have found that Seguda Valley went through a huge transformation. It was once covered entirely of water, up to an elevation of approximately 580 meters. The valley was filled with a great lake that was steeper than any of the great lakes. The entire African continent used to be a lot wetter than it is present day. Long ago, before even Selam and Lucyââ¬â¢s existence Africa was a wet tropical environment covered with rain forest. Eventually Africa began to dry out and the rain forests shrank. During Selamââ¬â¢s existence, 3-4 million years ago, Africa was a mosaic of different environments. Researchers know that from the fossils that live there, they tell a story of a vanished landscape. Fossils of creatures like a pig and hippopotamus. Today it is a vast expanse of volcanic rock and burning desert. 6. What are some of the different hypotheses presented in the film for why bipedalism emerged? One theory is that the mammals stood up to be able to see over tall grass. Second theory is that they stood up to be able to pick fruit off low branches of trees. (The way chimpanzees do today.) Third theory is that they stood up to cool more efficiently. ââ¬â Not as much sun beating on the body. * Most compelling hypothesis is that it saved us energy. 7. What is the molecular clock and how is it used to determine when two species last shared a common ancestor? It is a simple idea that the rate of change in DNA sequences is more or less constant over time ââ¬â a way of determining if and when two species shared a common ancestor. By counting the differences in the genetic code between chimps and humans researchers can calculate how long they have been evolving away from each-other. (5-7 years ago humans and apes shared a common ancestor.) 8. What is the clue that the ââ¬Å"Toumaiâ⬠fossil (Sahelanthropus tchadensis) is bipedal? The vital clue that the ââ¬Å"Toumaiâ⬠fossil is bipedal is how the skull connects to the spine. Researcher Michele could confer that by the shape of Toumaiââ¬â¢s skull. If the skull is placed on a neck of an ape that walks on all fours its eyes point down ward (not correct). If the skull is placed on an upright spine of a biped its eyes point straight ahead; for Michele this proved that Toumai walked upright. 9. How are the first stone tools identifiable as tools? Who is currently thought to be the first stone tool maker? The first stone tools were broken in a very particular way; there is a method behind how the rocks were broken in order to make it into a tool. Homo habilis (1.6-2.5 million years ago) are thought to be the first stone tool makers. 10. What is Rick Pottsââ¬â¢ idea about the role of climate in hominid adaptation? How is it different from traditional ideas? Rick Pottsââ¬â¢ observations let him to the new idea, rapid change as a catalyst for our evolution. 11. What was going on with the African climate when Homo habilis evolved? Africa had numerous climate changed from wet to dry, wet to dry, wet to dry all within approximately a thousand years.
Thursday, November 7, 2019
Engr. Essay Example
Engr. Essay Example Engr. Essay Engr. Essay water, farm inputs, micro climate, environment, machines and machine related parameters for optimum production of crop and animals (Engr. A.O. Ani 2010) Over the years, as a result of the illiteracy on the part of people in the third worldâ⠢s nations, there has been a misconception on the difference between agriculture and farmingâ⠢. According to Encarta encyclopedia, Agriculture: farming, is the occupation, business, or science of cultivating the land, producing crops, and raising livestock. Some say farming refers to the growing of crops while agriculture is a general name for all farm activities including the cultivation of land for the growing of crops and rearing of animals. The misconception was due to the use of other unexplained (which were misunderstood by the uneducated individuals) agricultural terminologies like fishery, processing, and deforestation etcetera. Precision Agriculture is the application of technologies and principles to manage spatial and temporal variability associated with all aspects of agricultural production for improving production and environmental quality. The success in precision agriculture depends on the accurate assessment of the variability, its management and evaluation in space-time distribution in crop production. The agronomic success of precision agriculture has been quite convincing in crops like sugar beet, sugarcane, tea and coffee. The potential for economic, environmental and social benefits of precision agriculture is largely unrealized because the space-time distribution of crop production has not been adequately addressed. Precision agriculture is a relatively new area that combines the latest in geographic technology with cropping situations to optimize inputs, reduce waste, and generate the maximum possible yields. The technology often involves the use of GPS and remote sensing for data collection, GIS for data processing and analysis, and variable rate technology for implementing ideal models. 1.1.2 NATURAL RESOURCES VARIABILITY: Soil and landscape variability, digital elevation models, soil mapping, geostatistics, geographic information systems, microclimate, weather forecasting, remote sensing, management units, scale, etc. 1.1.3 MANAGING VARIABILITY: Sampling techniques, site-specific nutrient and crop protection chemical recommendation, crop quality, tillage, seed density, seed variety, yield mapping, remote sensing, record keeping systems, data interpretation and use, crops (corn, wheat, sugar beets, potatoes, peanut, cotton, vegetables, etc.), management scale, etc. 1.1.4 ENGINEERING TECHNOLOGY: Computers, positioning systems, DGPS, machinery, tillage, planting, nutrient and crop protection implements, manure, irrigation, fustigation, yield monitor and mapping, soil physical and chemical characteristic sensors, weed/pest mapping, etc. 1.1.5 PROFITABILITY: MEY, net returns, BMPs, optimum recommendations, crop quality, technology cost, sustainability, social impacts, marketing, cooperatives, farm scale, crop type, etc. 1.1.6 ENVIRONMENT: Nutrient, crop protection chemicals, sediments, leaching, runoff, practices, field, watershed, on/off farm, artificial drainage, ground water, surface water, etc. 1.1.7 TECHNOLOGY TRANSFER: Skill needs, education, training, outreach, methods, surveys, agri-business, producers, distance education, Internet, simulations models, decision support systems, expert systems, on-farm experimentation, partnerships, quality of rural life, etc. 1.1.8 YIELD FORECASTING: Plant tissue absorbs much of the red light band and is very reflective of energy in near infrared (NIR) wavebands. The ratio of these two bands is referred to as the vegetation index (VI). The difference of red and NIR measurements divided by their sum is normalized difference VI (NDVI). For crops such as grain sorghum, production yields, leaf area index (LAI), crop height and biomass have been correlated with NDVI data obtained from multispectral images (Anderson et al, 1996). In order to get reasonably accurate yield predictions this data must be combined with input from weather models during the growing season (Moran et al, 1997). 1.1.9 MANAGEMENT DECISION SUPPORT SYSTEMS: Just having information about variability within the field doesnt solve any problems unless there is some kind of decision support system (DSS) in order to make VRT recommendations. Russo and Dantinne (Russo et al, 1997) have suggested the following steps for a DSS: 1. Identify environmental and biological states and processes in the field that can be monitored and manipulated for the betterment of crop production. 2. Choose sensors and supporting equipment to record data on these states and processes. 3. Collect, store and communicate the field-recorded data. 4. Process and manipulate the data into useful information and knowledge. 5. Present the information and knowledge in a form that can be interpreted to make decisions. Choose an action associated with a decision to change the identified state or process in a way that makes it more favorable to profitable crop production. 1.1.10 WHO IS FARMERS EDGE Farmers Edge offers a complete land management solution regardless if you are a 2000ac producer or a large corporate farm. ?à From project development to crop planning to operations and harvest management, Farmers Edge is dedicated to improving farmers land management practice by providing growers with solutions that increases their profits. Our land management solutions and services include advanced agronomy ââ¬Å" a balance of traditional agronomy and new technology, soils analysis, carbon aggregation, traceability and in-season crop monitoring and record keeping. 1.2.0 PRECISION FARMING TECHNOLOGIES Precision farming basically depends on measurement and understanding of variability, the main components of precision farming system must address the variability. Precision farming technology enabled, information based and decision focused, the components include,(the enabling technologies) Remote Sensing (RS), Geographical Information System (GIS), Global Positioning System (GPS), Soil Testing, Yield Monitors and Variable Rate Technology. Precision farming requires the requisition, management, analysis and output of large amount of spatial and temporal data. Mobile computing systems were needed to function on the go in farming operations because desktop systems in the farm office were not sufficient. Because precision farming is concerned with spatial and temporal variability and it is information based and decision focused. It is the spatial analysis capabilities of GIS that enable precision agriculture. GPS, DGPS has greatly enabled precision farming and of great importance to pre cision farming, particularly for guidance and digital evaluation modeling position accuracies at the centimeter level are possible in DGPS receivers. Precision farming technology (PF) is designed to provide data and information to assist farmers when making site-specific management decisions. By making more informed management decisions, farmers can become more efficient, and perhaps lower costs, and become more profitable. However, little is known about how farmers use PF to make management decisions, identify production problems, and about the relative magnitude of benefits and costs of PF on individual farms. 1.2.1 The global positioning system; The global positioning system (GPS) is a network of satellites developed for and managed by the U.S. Defense Department. The GPS constellation of 24 satellites orbiting the earth, transmit precise satellite time and location information to ground receivers. The ground receiving units are able to receive this location information from several satellites at a time for use in calculating a triangulation fix thus determining the exact location of the receiver. 1.2.2 Geographical information system; A geographical information system (GIS) consists of a computer software data base system used to input, store, retrieve, analyze, and display, in map like form, spatially referenced geographical information. Fig fig.1. A GIS chart showing the network link 1.2.3 Yield monitors; Yield monitors are crop yield measuring devices installed on harvesting equipment. The yield data from the monitor is recorded and stored at regular intervals along with positional data received from the GPS unit. GIS software takes the yield data and produces yield maps. | Fig.2. a representation of a yield map on a GIS system 1.2.4 VARIABLE RATE TECHNOLOGY; Variable rate technology (VRT) consists of farm field equipment with the ability to precisely control the rate of application of crop inputs and tillage operations. Precision farming technologies have been commercially available since the early 1990s, but the pace of adoption among U.S. farmers has been modest. This study examines the relationship between the adoption of diagnostic and application techniques of precision farming and sources of information available to farmers about precision farming. The model used in the analysis accounts for sources of self-selection in the adoption process that could bias the results. Results indicate interpersonal information sources have increased adoption relative to information from the mass media, and the private sector has been the driving force behind the diffusion of precision farming. Information from crop consultants and input suppliers has had the greatest impact on the adoption of precision farming technologies. These sources likely provide the greatest technical expertise about precision farming, and thus are better equipped to ease the significant human capital requirement of precision farming t echnologies. Fig. 3. Showing an automated precision maching carrying out a variable rate command. 1.3.0GLOBAL ADOPTION OF PRECISION AGRICULTURE TECHNOLOGIES The adoption of precision agriculture technologies has been uneven, both geographically andtemporally. The economic theory of induced innovation predicts that new technologies will be developed and adopted where they make more efficient use of the scarcest productiveresources. Indeed, adoption of precision agriculture technologies has been fastest where labouris costly but land and capital are relatively less costly. Where precision agriculture is beingadopted, the uneven adoption rate is tied to normal cycles for replacing the expensivemachinery in which many precision agriculture technologies are embodied. Equipmentreplacement decisions are affected by many factors exogenous to the farm, such as bankinterest rates and commodity prices. Adoption is likely to continue in labor-scarce, land-abundant countries, with rates of adoption accelerating when commodity prices are high andinterest rates low. Although spatial precision agriculture (PA) encompasses four key information technologies, farmers tend to use it in one of two major ways. The four PA technologies include location determination (via the Global Positioning System, GPS), computerized geographicinformation systems (GIS), computer-guided controllers for variable rate application (VRA)of crop inputs, and sensing technologies for automated data collection and mapping. TheGPS and GIS technologies underpin both of the major PA practices that farmers have begunto adopt. One of these is nutrient management; it involves spatially referenced soil sampling, often linked to VRA fertilizer spreading. The other is yield monitoring, usually tied to yieldmapping. In North America adoption is emerging for variants of these, such as VRA seedingand pesticide spraying, as well as remote sensing of plant vigor (Daberkow and McBride,2000). Some farmers adopt technology while others do not, due to different reasons. Either way, the pattern of PAtechnology adoption has been uneven. Despite the rapid growth of global commerce and thewidespread availability of equipment for VRA and yield monitoring, adoption rates appear todiffer sharply from one country to another, at least based on the informal data available (Norton and Swinton, 2001). Yield monitors are being adopted rapidly in Argentina, but lessso in Brazil or in France. Site-specific fertilizer use is rare in Argentina, despite the growth ofyield monitor use (Lowenberg-DeBoer, 1999). In Malaysia, site-specific fertilization is beingapplied to rubber plantations, but not to rice fields. Even within a country such as the UnitedStates, PA adoption rates vary by a factor of ten from 11.3% of farms in the MidwesternHeartland to only 1.1% in the Southeastern Seaboard in 1998 (Daberkow and McBride,2000). In general, we observe that in favored areas adoption of yield m onitoring or VRAfertilization has surpassed 5 percent only in the United States and Canada. It would appearthat adoption rates in the 1-5 percent range (again, only for favored subregions) may pertaining Australia, Brazil, Denmark, United Kingdom, and Germany. With the exception of a fewyield monitors in South Africa and some VRA fertilization in isolated plantation agricultureenclaves, adoption of PA technologies is virtually unknown in Africa.Rate of adoption is not smoothJudging from trends observed in the United States, PA technology adoption is uneven notonly geographically, but also temporally. The uneven adoption trendcontrasts sharply with the rapid, smooth adoption of hybrid maize following its commercial introduction about 80 years ago (Griliches, 1957; Lowenberg-DeBoer, 1998). Given thepotential benefits of precision agriculture for farm profitability and environmental protection, these uneven adoption patterns may seempuzzling.Agricultural technologies can be viewed as means by which farmers seek to achieve theirproduction objectives. Farmers have many objectives, including risk management, quality oflife, and environmental stewardship. But for the majority of farmers, who rely on agriculturalincome, expected profitability is the sine qua non, they must earn enough to stay in business.In attempting to produce profitably, farmers are constrained by limited access to essential productive resources such as land, labor, equipment, buildings, and management knowledge. Two characteristics are likely to drive the adoption of PA technologies. First, considering thatthey improve the efficiency of input use in mechanized agriculture, they are likely to beadopted first in those places where input use is already relatively efficient. Second, becausethese technologies use costly capital to automate human information processing, they will bemost attractive where capital is abundant relative to management labor. 1.4 0 A BRIEF HISTORY OF WORLD PRECISION FARMING Ever since man appeared on the earth, he has been harnessing the natural resources to meet his basic requirements. Reference to soil, water and air as basic resources, their management and means to keep them pure are mentioned in the Vedas, Upanishads and in ancient Hindu literature. The phenomenal increase in population of both man and animal in the last century and fast growing industrialization and urbanization in last few decades have overstrained the natural resource base, which are getting degraded much faster than ever before. Thus, the attention of whole world is focused on how to increase production to feed the burgeoning population and the question uppermost in every ones mind is Can we produce enough food in a sustainable manner without damage to the natural resource base For over the last 15 years, precision agriculture has been practice in some parts of the world and despite its promising future, it has not yet managed to be adapted globally by farmers. To the Europeans, Precision Farming is old traditional farming in the modern way. Initially, precision farming took the form of a move away from blanket applications of inputs, increasing in sophistication as developments in technology advanced to enable variable application rates only applying fertilizer and chemicals where they are required and at the optimum rate. Generally, the adoption of precision farming has been modest in Europe as it is advancing to livestock precision application e.g. robotic milking of cattle and the possibility to determine the satisfaction rate of the beast using his mooâ⠢ sound. And also, the potential for using precision agriculture to address environmental, food safety, animal welfare and sustainability problems seems to be attracting political attention in Europe. Amongst all this good that have befalling upon the European system of agriculture, there are still some lapses in the southern part of Europe where only a few countries e.g. France, Sp ain, and Portugal have been very successful with breaking loose from their traditional pattern of agriculture. The Americanâ⠢s attitudes of doing things in a unique format have always paved a way for them around the blue globe. This is evident on their adoption of precision farming as they grow rapidly with the aim of input minimization and output maximization. Series of achievements have been made by the Americans within this few years of the emergence op precision agriculture the most striking of them all is the commissioning of a GPS system developed for and managed by the U.S. defense department. Precision farming in America has been very successful as it has been adopted by several countries especially Argentina, U.S.A., Columbia, Brazil, Chile, etcetera. Australian growers are finding practical and profitable uses for precision agriculture, but the uses differ somewhat from those common in the US. Yield monitoring is relatively common, but as in the US many yield monitors are not linked to global positioning systems (GPS). High soil testing costs have discouraged US style variable rate fertilizer and growers are searching for alternative ways to develop variable rate application (VRA) fertilizer recommendation maps. Because of severe soil compaction problems, GPS guidance for controlled traffic is considered by some to be the best starting point for precision agriculture. Asia, a world of science and technology, a place where at the mention of the word innovationâ⠢, one is welcomed as an ambassador of the jet age. In countries like Japan, small areas are utilized in farming by using greenhouses to plant crops and vegetables. Japanese farmers are equipped with skills in such a way that production can be done simultaneously, thus, making large production at small areas by as many farmers as possible. By this medium, the Japanese government has been able to lunch a campaign against hunger and corruption in the country. China, being the back bone of Asia technology growth as found a way to defy the might of the GPS scarcity their by reducing the problems of traffic in precision agriculture by the lunching of space satellites to manage field monitoring activities. Some great nations like Taiwan, Japan, China, Korea, and etcetera have found a way to embrace and manage precision farming for the betterment of their world. Africa being the most backward technologic-wise among all continents as just a little to show for precision farming. Some countries like South Africa and Zambia tops the chart of Nigeria precision farmers while other countries like Nigeria, Cameroon, Ghana, Kenya etcetera only applied some precision operations into mechanized farming. Precision farming as developed over the past decade, having is origin in Europe. As often the case with new technologies, this practice was taken up in the US and developed at great past. Precision farming is about to change the face of agriculture, as we know it today. Precision farming has been developed mainly in Europe (Moore 1998a). It has, however, been adapted by North American farmers in far greater numbers than in any other part of the world. Various sources show that probably around 90% of all precision farming system operates in US and Canada (Starck, 1998). 1.5.0 PRECISION FARMING IN NIGERIA Precision farming provides a new solution using a systems approach for todays agricultural issues such as the need to balance productivity with environmental concerns. It is based on advanced information technology. It includes describing and modeling variation in soils and plant species, and integrating agricultural practices to meet site-specific requirements. It aims at increased economic returns, as well as at reducing the energy input and the environmental impact of agriculture. This is very possible in Nigeria if only Nigerians will allow it be, putting together a combined effort to achieving the highest point of application of farming technologies. 1.5.1 A New Concept; This article is concentrated on the possibilities of the introduction of precision agriculture in Nigeria. Of a truth, there is no such thing as precision farming presently in Nigeria today because all there is are some elements of precision agriculture like the use of sensors and some field monitoring devices to manage crop yield, productivities, variation in soil nutrients and climatic changes as they affect food availabilities. For example in kwara state, yield monitors are been use to monitor the production of selenium production. This practice is been supported by kwara state government as a preferred way of site specific management. Actually, precision agriculture as a new concept In Nigeria if adapted will bring about a sudden transition from traditional farming (as practiced in most parts of Nigeria) to a better and more advanced level of farm variability management. This whole scenario will involve an experience of the term evolutionâ⠢ in its entirety. Apart from the self motivation required of Nigerians and monetary support on the part of the Nigeria government, there are other challenges faced by the nation that will militate against the introduction and proper functioning of precision farming in Nigeria. But before we delve into this sub problem proper, lets first take a look into the geography of Nigeria to see if the land his been favored by nature for this effect. 1.5.2 Precision Farming VS Traditional Farming; just like in a football match between Manchester united FC and Chelsea FC, there is absolutely no basis for comparism between both club teams because Chelsea f c is of no match for man u. precision agriculture have in time encompass traditional farming in all ratification. The advent of machine aided implement with precise application of variable technology to the farmland form the basis and justification of precision agriculture. Just as in the game of football, all the department of precision agriculture works more than those of traditional farming also called (which can either be hand-tool or draught- animal farming). also, the variation in quality, quantity and production factor differs a great deal. Never the less, tradition agriculture is the ancestor of precision agriculture and this is the more reason why Nigerians should embrace precision farming and move forward on the field. 1.6.0 GEOGRAPHY OF NIGERIA Nigeria, one-third larger than Texas and the most populous country in Africa, is situated on the Gulf of Guinea in West Africa. Its neighbors are Benin, Niger, Cameroon, and Chad. The lower course of the Niger River flows south through the western part of the country into the Gulf of Guinea. Swamps and mangrove forests border the southern coast; inland are hardwood forests. The first inhabitants of what is now Nigeria were thought to have been the Nok people (500 BC ââ¬Å"c. AD 200). The Kanuri, Hausa, and Fulani peoples subsequently migrated there. Islam was introduced in the 13th century, and the empire of Kanem controlled the area from the end of the 11th century to the 14th. The Fulani Empire ruled the region from the beginning of the 19th century until the British annexed Lagos in 1851 and seized control of the rest of the region by 1886. It formally became the Colony and Protectorate of Nigeria in 1914. Nigeria has two broad belts of vegetation types, namely, the forest and savannah types. There is, however, also the mountain vegetation of the isolated high plateau regions in the central and far eastern parts of the country. Fig.4. a map of Nigeria showing the major towns and cities. The subhumid zone of Nigeria covers 455 000 km2 or approximately half of Nigeria and a third of the zone in West Africa. Typically low in carbon and nitrogen, the soils have a tendency to form hard crusts. They have a poor capacity for retaining nutrients, poor water penetration and shallow water tables, all of which adversely affect cropping potential. Rainfall in the zone ranges from 1000 to 1500 mm, with growing season from 180 to 300 days per year. The zone offers a wide variety of cropping options, but the growing season is invariably punctuated by dry spells. There is high runoff. During the growing season the humidity is conducive to pathogen survival and transmission. In the dry season the vegetation is subject to burning The zone has five vegetation subzones, but the Guinea and derived savanna subzones account for some 90% of the zone. There is good vegetation cover, although it is dominated by varieties suited to impoverished soil conditions. The feed quality of the grasses rises after the onset of the rains, but declines rapidly after they stop and is low for most of the year. The pattern of vegetation and land use form a mosaic of medium to high levels of cultivation, grassland and woodland. Twenty percent of the zone is cultivated, and cultivation is expanding at 4.8% per annum. It is estimated that by the turn of the century 33% will be cultivated. This estimate is well below the former one of 70%. Crop yields cannot be sustained on cleared land for more than 3 years without fertilizer or manure. There are opportunities for introducing forage legumes, but such interventions must be in accord with intricate and well established mixed cropping systems. The bigger the contribution of forage legumes to soil fertility and hence to food crop yields, the better the chances of their adoption. 1.6.1 Vegetation zones in Nigeria; Vegetation, simply defined, is the plant cover of the earth consisting of assemblages of plants. Broadly speaking, the national vegetation over a geographical area is essentially a response to the climate in that area. Nigerias vegetation belts reflect this very close link between vegetation and climate. Hence, the similarity in the west-to-east zonation of both climate and vegetation. With the south to north progressive decline in total rainfall and length of wet season, vegetation belts are demarcated on west-to-east zonation pattern characterized by transitional zones from one belt to another. The forest vegetation zone of Nigeria consists of; 1. Saline water swamp 2. Freshwater swamp 3. Tropical evergreen rainforest. While the savannah vegetation zone of Nigeria consist of; 1. Guinea Savannah 2. Sudan Savannah; and 3. Sahel Savannah. One major characteristic of savannah vegetation is that trees vary in size and density from the Guinea, through the Sudan, to the Sahel Savannah. If all this are as correct as they seem, then nature her self must have specially designed Nigeria as a country in a unique manner, giving her a format that will favor all manner of crop as their production possibility strength varies across the various vegetation zones. Also, the soil type distribution in Nigeria is in a unique format varying from sand to gravel in different parts of the country and this is one reason why the nation is very rich in minerals and natural resources. Putting all this together, it is evident that the Nigeria geography is by no means a factor or an excuse militating against the adoption and growth of precision farming with as its innovative ideas. 1.6.2 Geology More than half of the Nigerian subhumid zone is covered by Pre- to Upper Cambrian basement complex. It includes the oldest rocks known in Nigeria, principally composed of metamorphic and igneous material. Over most of the area underlain by basement complex there is a discontinuous mantle of weathered gneiss and granite, but this is generally thin, with a high clay content, and does not serve as an efficient aquifer. The water tables are shallow and adversely affect crops and cropping potentials at the height of the wet season. The soil tends to form a hard crust after the first rains, effectively preventing penetration of water and seedling emergence. It therefore needs tillage for cropping. Areas with excessively coarse materials, a poor capacity for retaining nutrients due to low cation exchange capacity, and topography exceeding 2-3% slope are normally avoided by farmers. Under the traditional production system long fallow periods are necessary for maintaining soil fertility. 1.6.3 Relief For an area covering half a million square kilometres, the variation in relief within the subhumid zone is limited. Four major relief types can be identified: The Niger-Benue trough is a Y-shaped lowland area which divides the subhumid zone into three parts. It has been deeply dissected by erosion into tabular hills separated by river valleys. The Niger section is especially rugged. The upland areas north of the Niger-Benue trough, and west of the Niger river, are generally undulating and strongly marked by inselbergs. The north-central plateau is made up of two different platforms the high plains of Hausaland, which at an average height of 600 m a.s.l form the first step, and the Jos Plateau at an elevation of between 1000 and 1800 m forming the second step. The latter falls outside the subhumid zone. The area south of the Benue and east of the Niger, extending eastwards as far as 9?30E, consists of the lowland Cross River plains, east of Enugu, which show outcrops of limestone and shales whereas the relief in general is gentle; and the scarplands west of Enugu, which are made up of the Udi and Awka-Orlu plateaux. 1.6.4 Sunshine and radiation The maximum seasonal variation in day length in Nigeria is 1 hour and 45 minutes. This variation is sufficient to cause differences in the performance of crops sensitive to photoperiodism. The mean annual number of hours of sunshine increases progressively to the northeast. The daily mean duration of sunshine in July, at the height of the rainy season, is greater in the north than in the south, where the cloud cover is more constant. The same pattern is observed in January, when there is a general lack of cloud cover in the north, but due to humid air from the Gulf of Guinea cloudiness may be expected in the south. This results in a marked zonal pattern when the whole of Nigeria is considered. The northern part of the subhumid zone stands out as having the highest national values of net radiation. Further to the north, outside the zone, surface albedo is higher, reducing net received radiation. 1.6.5 Rainfall Most of the Nigerian subhumid zone lies between the 1000 mm and 1500 mm isohyets, offering a wide choice of crop options. Rainfall is governed by the annual passage of the Inter-Tropical Convergence Zone (ITCZ), the meeting point of a dry northeastern low-pressure air mass and a moist southwestern high-pressure air mass. The northeastern movement of the ITCZ and the rain-bearing winds that accompany it mark the onset of the rainy season. Its southwestward movement and the accompanying harmattan winds mark the beginning of the dry season. Annual rainfall and its reliability decrease from the south northwards. The northern part of the zone has unimodal rainfall distribution in which rains increase in frequency and amount, beginning in May and peaking in August. In the southern part the rainfall pattern is bimodal, the first peak occurring in June-July, and the second in September, with August relatively dry. Variations in annual rainfall make it difficult to draw a strict geographical boundary between these two distribution patterns. Much of the subhumid zone is transitional between unimodal and bimodal rainfall distribution. The rains are expected to reach the southern boundary of the subhumid zone at the beginning of March, and the northern boundary 2 months later (Walter, 1968). At the northern boundary the rainy season normally ends in early October, and at the southern boundary 6 weeks later. The expected duration of the wet season in the subhumid zone thus ranges from 5 months in the north to more than 8 months in the south. Nevertheless the season (April to October) is invariably punctuated by dry spells, the length of which varies from a few days to a few weeks. Evapotranspiration exceeds rainfall north of latitude 7?à °30N (Kowal and Knabe, 1972), although almost everywhere in the zone there appears to be a period of water surplus in the year when rainfall exceeds evapotranspiration. Rainfall is usually torrential, 25 to 50 mm or more often falling within 1 hour. Measurement of infiltration or rainfall acceptance on a ferruginous soil type using catchment gauges gave an average ultimate infiltration of 24 mm/hour. Rainfall exceeding this rate can cause serious erosion and runoff. High humidity and concentrated rainfall during the growing season are conducive to pathogen survival and transmission. The dry season, on the other hand, is severe and the vegetation becomes parched and easily combustible. 1.6.6 Major soil types Ferruginous tropical soils cover approximately half the Nigerian subhumid zone. These soils are generally characterized by a sandy surface horizon overlying a weakly structured clay accumulation. Their base-exchange capacity is low, but their base saturation and pH values are relatively high. They have high natural fertility, and FAO (1966) rates them as having good potential. However, under traditional management practices ferruginous tropical soils are of low productivity, are sensitive to erosion and have low water-holding capacity. The alluvial soils found along the Niger and Benue rivers show light accumulations of organic matter but are often, under traditional management practices, too wet during the rainy season for crops other than rice. Under improved management practices, including irrigation and drainage, these soils have been classified by FAO (1966) as having strong to good potential, depending on their local texture and salt content. The ferralsols that occupy much of the other half of Nigerias subhumid zone are deep, strongly weathered soils of friable consistency. They have a low base-exchange capacity, low pH values and generally low nutrient contents. However, their resistance to erosion and good physical properties make these soils suitable for a wide range of crops. The ferralsols within the subhumid zone are categorized by FAO as soils of low present productivity, but as having medium potential if their management can be improved. The lithosols found in the north-central part of the zone are of local significance only, and have been classified by FAO as being of variable productivity and potential. Under traditional management they are dry for 6 to 8 months of the year. In addition they are shallow, moderately leached with little organic matter, and have a low base-exchange capacity. The vertisols found in a small area west of Yola are difficult to work under traditional management practices. They crack deeply when dry, and have a heavy dark texture when moist. They are therefore of only medium productivity, in spite of being generally high in nutrients. Under improved management practices, FAO classifies these soils as having good potential. The soil properties in ILCAs case study areas are shown in Table 1. Table 1. General soil properties in two ILCA case study areas. Location | pH | Organic C (% | Total N (%) | Available P (ppm) | Ca (Meg/100 g) | Mg (Meg/100 g) | Mn (Meg/100 g) | K (Meg/100 g) | Total acidity | Kurmin Biri | 5.2 | 0.58 | 0.071 | 3.9 | 1.12 | 0.37 | 0.02 | 0.13 | 0.78 | Abet | 5.3 | 0.36 | 0.086 | 1.8 | 1.04 | 0.49 | 0.11 | 0.13 | 0.46 | 1.6.7 Vegetation and land use; The subhumid zone includes five vegetation subzones, excluding those found at high altitude. The Guinea and derived savanna subzones occupy some 90% of the area. The areas of Nigeria where mans influence on the vegetation is greatest lie to the north and south of the subhumid zone, exemplified by conditions in the Sahel and by the diminishing rain forest. Blair-Rains (1968) stated that the existing vegetation in Nigeria in general may bear little resemblance to the original zonal categories, because of the combined effects of human activity: burning, cultivation, tree felling and cattle grazing. Extensive areas of medium to high levels of land-use intensity are found on the northern border of the subhumid zone extending northwards, with the highest cultivation density being associated with major towns. The same pattern is found on the southern border, around Enugu, and southwards, where the proportion of land cultivated reaches its highest, at 25%. The land in between these two areas falls within the subhumid zone, where cultivation declines to some 17%. Here the pattern of vegetation and land use can best be described as a mosaic of varying levels of cultivation, grassland and woodland. An interconnecting patchwork of more intense cultivation links the northern and southern cultivated regions of Nigeria, through a broad belt north of Lokoja including Bida, Minna, Abuja, Lafia, Shendam, Kafanchan, the Jos Plateau, Kaduna and Saminaka. In this belt, cultivation reaches a peak of 35%. To the west and east of it, cultivated areas are generally more scattered (10%) with woodland tending to predominate. 1.6.8 Distribution of cultivation Bourn and Milligan (1983) estimated 20% of the Nigerian subhumid zone to be under cultivation. The overall distribution of this farmland, and hence the intensity of land use, are represented by the three-dimensional surface shown in Figure 1, in which the proportion of land under cultivation is indicated by apparent height. As already suggested by the side-looking airborne radar (SLAR) vegetation and land-use map, cultivation was found to be unevenly distributed within the subhumid zone, being concentrated in a series of semi-isolated peaks of high-intensity land use, surrounded by areas of relatively low cultivation. However, an important feature indicated in Figure 1 but not evident on the SLAR map is that cultivation is taking place throughout the surveyed area, albeit at very low levels in the more western areas and to the southeast. Putt et al (1980) have demonstrated a rapid rate of agricultural expansion, associated with human population increase, both within and outside the subhumid zone. In the Lafia region, for example, comparative airphoto-interpretation indicated that cultivation was expanding at an annual rate of 4.8%. Assuming continued expansion at that rate (plus or minus 1%) and an estimated 20% of the zone to be cultivated at present, Figure 2 projects the increasing proportion likely to be under cultivation to the turn of the century. Even the higher estimate of 33.1% under cultivation is very much below the previous estimate of 70% for the zone as a whole (ILCA, 1979). Since approximately one third of the West African sub humid zone is in Nigeria, the figure of 70% would appear to be an overestimate. Fig.5. showing the distribution of cultivation 1.6.9 Forage resources; The herbaceous cover of the subhumid zone consists mainly of annual grasses, with a very low percentage of native legumes. Seasonal changes in herbage quality are primarily due more to changes in plant development than to climatic conditions per se. The C4 photosynthetic pathways in grasses promote a rapid accumulation of structural components, resulting in dilution of nutrients such as N and P in the tissue. Legumes on the other hand, exhibit a less efficient C3 photosynthetic pathway and are independent of soil N. which is secured through biological fixation in the root nodules. Legumes are therefore usually higher in protein and minerals and have higher dry matter (DM) digestibility and voluntary intake by animals than do grasses at similar stages of growth. Growing forage legumes should thus provide a means of overcoming the protein deficiency of the grasses which dominate natural feed supplies. 1.6.10Forage productivity; 1.6.10.1 Measurement Land-use patterns affect the productivity of natural forage. Because of its favourable rainfall the subhumid zone is also likely to be increasingly utilized for cropping wherever edaphic and other conditions are favourable. Forage productivity measurements were carried out in two environments where pastoralists are settling: 1. An intensive arable farming area (Abet). 2. An area reserved by the state for grazing (Kurmin Biri Kachia). An inventory, and the frequency, of existing flora in the herbaceous cover were compiled by using line transects. A number of transects were read in three distinct ecological niches in each study area. Potential yield of the herbaceous strata of the three ecological subdivisions was estimated from five samples of 1 m2 each, clipped to ground level at the beginning and end of the rains, within a 5 x 5 m enclosed area protected from livestock throughout the growing season. Monthly forage production and botanical composition were also estimated from 1 m2 samples, clipped to the ground within similar enclosures as above, but moved randomly after each monthly clipping. Weight difference or DM disappearance between clipped samples from within and outside the enclosures was assumed to have been grazed by livestock during that month. Cut samples, hand-separated into grass and non-grass (forb), were taken, dried and analysed for crude protein (CP) and DM digestibility. Data collected from the three ecological subdivisions were pooled to construct a generalized pattern of forage production in the subhumid zone (Figures 3 and 4). One season of uninterrupted growth of the herbaceous stratum in a burnt area in the subhumid zone produced a DM yield of 2250 kg on shallow, ferruginous soils. Fadama (lowland) soils, with deep hydromorphology, tend to support higher DM productivity up to 5 tonnes in one growing season (Table 2). On this soil type forage growth is prolonged by residual moisture long after the rains have ceased (Figure 5). Fig.6 Table 2. One seasons DM production (kg/ha)a/ of the herbaceous layer in different eco-subsystems in two study areas of the subhumid zone of Nigeria. | Fadama | Woodland | Scrubland | Riverine | Kurmin Biri | 3754 | 1758 | 2251 | 2156 | Abet | 4922 | | 2185 | 1940 | a/ Uninterrupted growth. Herbage growth and production varies seasonally, and the maximum herbaceous biomass on offer is attained between August-September (Figures 3 and 4). Seasonality of production also affects non-graminoid components, and their proportion in the total biomass is higher at the beginning of the rainy season (Table 3). Non-graminaceous types are insignificant in the herbaceous layer, especially in burnt areas. Productivity of the herbaceous cover also varies between years. Herbage produced in the fadama at Abet was about 1 tonne higher in 1981 when the area received 167 mm more rain than the previous year. Both seasonal and species differences contribute to changes in forage quality. During their early development grasses increase in protein content. Where conditions are favourable, the release of soil nitrogen early in the growing season may increase their CP to 9%. But once the rains are over CP content declines rapidly, and since the main bulk of forage on offer is grass, the overall nutritive value of the herbaceous cover in terms of protein is low for most of the year. Table 3. Botanical composition of the herbaceous layer of two ILCA case study areas in the subhumid zone of Nigeria (kg/ha). Study area/Months | Grass | Forb | Total | % Forb | Kurmin Biri | January | 612 | | 612 | | February | 504 | | 504 | | March | 144 | 76 | 220 | 34 | April | 288 | 172 | 460 | 37 | May | 714 | 206 | 920 | 22 | June | 1573 | 301 | 1874 | 16 | July | 1799 | 368 | 2162 | 17 | August | 2298 | 431 | 2729 | 16 | September | 2380 | 437 | 2817 | 18 | October | 1980 | 386 | 2366 | 16 | November | 1200 | 285 | 1485 | 19 | December | 826 | 165 | 991 | 20 | Abet | January | 1382 | | 1382 | | February | 322 | | 322 | | March | 290 | | 290 | | April | 518 | 93 | 611 | 15 | May | 910 | 203 | 1113 | 18 | June | 1502 | 328 | 1830 | 18 | July | 2193 | 166 | 2359 | 7 | August | 2811 | 189 | 3000 | 6 | September | 3094 | 226 | 3320 | 7 | October | 2729 | 218 | 2947 | 7 | November | 2688 | 163 | 2851 | 6 | December | 2212 | 94 | 2306 | 4 | The digestibility of grass is low throughout the year (Figures 3 and 4). It exceeds 40% for only 4 months during the growing season, when the tissues are tender. Digestibility changes closely follow the level of protein in the tissue (Figure 6). This correlation highlights the importance of increasing protein levels in the forage. Fig. 7 Livestock, through selective grazing, tend to consume a better quality diet than average protein and digestibility levels would suggest. Analyses of grab samples collected by following animals showed higher protein content and digestibility throughout the year (Figure 7). The overall quality of forage from a burnt area was also higher. Burning as early as October-November increased the quality of regrown forage, but the bulk left at the end of the growing season was very low in quality and therefore less utilized by livestock, which prefer the new flush of shoots induced by burning (Figures 3 and 4). fig. 8. Indications are that forage utilization in more intensively farmed areas is higher than in other areas, possibly because of the tendency of pastoralists to settle near arable farmers. 1.6.11Forage composition and availability The sub humid zone has good ground vegetative cover. Empty spaces in any area account for 8 to 17%, depending on the type of soil, available moisture and the level of land use. Grasses make up about 62 to 82% of the total herbaceous forage. Leguminous species are very low. Other short-growing dicots, associated with grass, make up about 10 to 20% of herbaceous cover (Table 4). Table 4. Composition of the herbaceous cover of three eco-subsystems of the subhumid zone (%). | Eco-subsystem | Plant cover | Fadama | Scrubland | Riverine | Total plant cover | 92.1 | 83.7 | 83.2 | Grass | 82.0 | 64.2 | 62.3 | Legumes | 0.7 | 4.4 | 1.4 | Others | 9.4 | 15.1 | 19.5 | On the basis of percentage frequency, Rattray (1960) used a given grass genus that emerged as the dominating type to designate a particular climatic zone. Accordingly, the subhumid zone of West Africa could be divided into three belts that cross the south-north axis: the Pennisetum, Hyparrhenia and Andropogon belts. These dominant species have given way to others over the years, doubtless as a result of human influence. The graminoid types in both the ILCA study areas are dominated by Loudetia simplex, which is a tufted perennial, suggesting impoverished soil conditions (Table 5). Table 5. Frequency distribution of the major grasses in the herbaceous cover of the Kachia Grazing Reserve. Grasses | Occurrence (%) | Andropogon spp. | 6.2 | Brachiaria spp. | 8.3 | Digitaria spp. | 0.8 | Hyparrhenia spp. | 11.4 | Loudetia spp. | 40.7 | Panicum spp. | 0.8 | Paspalum spp. | 1.4 | Setaria spp. | 0.6 | 1.6.12Forage constraints and interventions 1.6.12.1Cropland Land cleared and prepared for cropping has an unprotected surface and therefore deteriorates rapidly under the impact of the torrential rains typical of the subhumid zone. Clearing increases surface runoff and leaching of nutrients. Moreover, the temperature of an unprotected soil surface tends to be higher, which encourages more rapid decomposition of organic matter than in a soil with a natural vegetative cover. Soil undergoing degradation at such a rate cannot support continuous cropping unless its lost properties are restored in some way. When such a soil is cropped repeatedly, crop yields decline and the capacity of the land to support human life diminishes with time (Table 6). Experienced farmers are able to predict the time limit for profitable cropping once an area is cleared, which generally ranges from 1 to 3 years unless manure or fertilizer is applied. Table 6. Productivity of sorghum (kg/ha) when cropped for 3 years continuously with or without manure additions (Kurmin Biri, 1981-1983)a/. ?à | Year | | 1981 | 1982 | 1983b/ | Without animal manure | | | | | Grain yield | 858 | 690 | 267 | | Crop residue | 4330 | 3740 | 2133 | With animal manure | | | | | Grain yield | | 1352 | 933 | | Crop residue | | 5710 | 4000 | Each replicate in the trial was divided into two, and 20 to 30 animals were confined for 5 days on one half, prior to land preparation in 1982 and 1983. b/ In 1983 there was a very short wet season compared with previous years. Soil fertility is traditionally restored by fallowing. The length of time the soil is rested after cropping is generally a function of population pressure. Where population is low, rest periods between cultivated phases may be prolonged, resulting in a low cropping index. In this system a farmer has to clear a new area for cultivation each time he abandons the old one. Soil restoration is left to take a natural but prolonged course with no inputs from the farmer. Areas with a low cropping index can provide reasonably well regenerated land whenever this is required by farmers, Higher population levels make prolonged fallow periods less feasible. Farmers are obliged to return to a previously cropped area much sooner. Incomplete recovery then has to be compensated by additional inputs to make the soil productive. The return of ash, household sweepings, night soil and, of course, fertilizers to the land are some of the measures used. For the farmers in parts of Nigerias sub humid zone, access to manure plays a very significant role in the maintenance of soil fertility with or without short rest periods. Manure allows intensive cropping and hence higher human support capacity per unit area of land. Crop and livestock production are commonly carried out by ethnically separate communities, although mixed farming is increasing in Nigeria. Fulani pastoralists prefer to settle in the vicinity of cereal farmers, who thus have access to manure even if they do not own livestock themselves. Animals can also be used for traction and transport, besides being a source of much needed protein. For all the contributions of livestock, the crop sector at the moment tends to offer only crop residues and unimproved fallows in return. Although valuable to livestock early in the dry season (Paper 14), crop residues alone are inadequate to meet the nutritional demands of animals. Growing cereal crops and forage legumes in a mixture is a recent concept in African agriculture. Both components in the mixture require a different production emphasis (grain from cereals and hence emphasis on the reproductive phase, but herbage from legumes, and hence emphasis on the vegetative stage). The agronomic requirements of a cereal/forage crop mixture differ from those of other conventional crop mixtures. Research carried out by ILCA in the past 3 years indicates that forage legumes can be incorporated into existing cropping systems by simple adjustments of sowing time, plant densities or planting sequences. These adjustments improve the nutritive value of crop residues and hence the economic returns per unit area of land. Mixed cropping is the basic farming practice in the sub humid zone of Nigeria. Sorghum is the principal crop and predominates in the different crop mixtures. Most commonly, it is intercropped with soybean and/or maize, but various other crops, such as groundnut, cowpea, millet, and okra, also feature. Farmers reasons for growing a mixture of crops are to minimize risk, spread labour inputs, and reduce disease problems (Evans, 1960; Norman, 1974). These advantages outweigh the benefits of sole cropping, and mixed cropping will doubtlessly remain the standard practice in the sub humid zone for the foreseeable future. Yield advantages in mixed as compared to sole cropping are also common when the component crops complement each other. This happens when their growth patterns differ in time, so that each crop makes its major demands on resources at different times (Wiley, 1979). It will be possible to incorporate forage legumes into crop mixtures only if appropriate adjustments can be made to cropping patterns. These adjustments should not be too far removed from the existing practices if they are to be adopted easily by the farmers. 1.6.12.2Rangeland Natural forage provides the cheapest source of nutrients for ruminants, but the land on which it grows does not often have a high capacity for biomass production. The deflected or disclimax vegetations typical of such land are also likely to increase with the spread of human activity into areas which are as yet underutilized. These areas will not revert back to climax floral associations whilst under continued pressure from man and stock. Livestock grazing natural rangeland derive most of their feed from grasses, with browse becoming increasingly important (but never dominant) as the dry season progresses. High costs and the communal ownership of rangeland preclude large-scale pasture development in Nigerias subhumid zone. Unrestricted access and widespread burning have so far frustrated conventional range management strategies. Small units of sown forage might nevertheless be respected on private property just as cereal crops are. The Fulani in the ILCA case study areas have traditionally sown fonio (Digitaria exilis) on areas grazed and trodden by cattle. This technique can be adapted to provide the labour required for legume establishment. Small units are probably a safer investment than large ones, owing to the risk of fire. 2.0 CHALLENGES Now, letâ⠢s take a look at the various potential challenges militating against the practice of sustainable precision farming in Nigeria. This set backs are numerously as large as the nation herself but can be grouped into various broad classes as discussed below; 2.1Socio-psychological challenges: being the most critical among the various problems faced by not only precision agriculture but by farming in general, socio-psychology talks about the mind- set of the people about a given concept. In Nigeria today, farming is been perceive as a dirty job since the advent of the so called petroleum which is seen as a white collar job (office job) and as taken over the consciousness of the people. Also, people radar work in an air-conditioning office and receive a low income than aspiring for a better economy in the farming sector. Food scarcity is attaining its climax as hunger, death, and diseases as taking over the peace and unity of the states yet we still wallow in in-depth ignorance. Also, looking at the name farmingâ⠢ which is the mother name of agricultureâ⠢ has been neglected just for the reason of acceptance by the ignorant nation. In most learning institutions in Nigeria, names have been changed from agricultural engineering to b iological engineering, bioresources engineering, and etcetera for the senseless reason of rebranding. We talk about enlightening the nation but yet we live in the shadows of our fear for a world full of politics. We bear a name national association of agricultural engineer (NIAE)â⠢ yet we allow the chuckles of fear obtain the better part of us without considering properly what fate in the future have for us. There is no crime on becoming the vibrant minorities were the voice of the people is to be heard and acknowledge for his stronger will and love for his mother land. If proper precautions are not taken, the name agricultural engineersâ⠢ will be erased from the pages of history. The economy of Nigeria historically was based on agriculture, and about 70% of the workforce is still engaged in farming (largely of a subsistence type). The chief crops are cocoa, peanuts, palm oil, corn, rice, sorghum, millet, soybeans, cassava, yams, and rubber. In addition, cattle, sheep, goats, and pigs are raised. But nowadays, Petroleum is the leading mineral produced in Nigeria and provides about 95% of foreign exchange earnings and the majority of government revenues. With oil as a basic source of income for the nation, the government as loosed interest in the farming and everything that concerns the agricultural sector. Now what will be the fate of precision farming in a country where the government pays little or no interest in agriculture 2.2Land tenure system: land ownership and land fragmentization is yet another common factor militating against commercialization in the farming sector. Some may say that commercial farming neutralizes land fragmentization but taking a critical look at the subject matter, they are both linked up one way or the other. Taking for an instance a commercial farmer pledging for a land from a community man having six kid and he is willing to loan the land to the farmer for a period of time but with the permission of his children. If three of the children refuse to loan their portion of the land for some individual reasons, then land fragmentization has directly or indirectly affected agriculture commercialization. Also, land ownership by communities which can only be use by community members as created a restriction for aspiring alien precision farmers their by militating against precision agriculture in such areas of promising yield. 2.3 Technological awareness: Nigeria technology growth is on a creeping motion yet it is regarded as one of the fastest growing technological economy in Africa. Since the official lunching of the GSM device on the 6th of October 2001, there have been series of improvement in the technological sector but Nigerians believe that the best is yet to come. 2.4Infrastructural facilities and basic amenities: when talking about infrastructural facilities and basic amenities as they affect precision farming, it covers the application of precision farming technologies and their variations in time. The first step to be put into consideration to getting started with a full-time precision agriculture after the acquisition of land is the construction of a base centre for data collection, storage, and information command dissemination. This brings us to the challenges militating against the introduction of precision farming in Nigeria. The cost of building a standard base centre in Nigeria is very expensive as it involves the use of un-common and expensive technologies. The various precision technologies are been discussed in detail by Okwudiuche F.O. (2010). Also, the basic amenities required for the proper functioning of precision farming are practically not available in the country. This is a basic set back in the introduction of precision fa rming in the country. These basic amenities include electricity, road, water, and precision facilities which are the function of the government to provide the country with. Not to talk about the issue of electricity which has become outrageous. The Nigeria road is nothing to write home about and that of the scarcity of a natural resource as free as water is the most disgraceful of it all. Here, it is evident that the introduction of precision farming in Nigeria means rebranding Nigeria for the better, as it affects basically all aspects of living of the people. Also, precision machines are very expensive to come by especially when they are emerging technologies. There are also some factors to be considered when choosing a precision machine which include the workability of the machine involving weather as a factor in the machine production. Some machines are design to suite into the weather conditions which can be another factor in the design mechanism of a precision machine in other for it to be durable and work precisely. For instance, in the design of a sensors and telemetry for the collection and transmission of data from to the base centre, the weather condition of the region must be put into consideration because the use of sensors and t
Tuesday, November 5, 2019
How to Demagnetize a Magnet
How to Demagnetize a Magnet A magnet forms when the magnetic dipoles in a material orient in the same general direction. Iron and manganese are two elements that can be made into magnets by aligning the magnetic dipoles in the metal, otherwise these metals are not inherently magnetic. Other types of magnets exist, such as neodymium iron boron (NdFeB), samarium cobalt (SmCo), ceramic (ferrite) magnets, and aluminum nickel cobalt (AlNiCo) magnets. These materials are called permanent magnets, but there are ways to demagnetize them. Basically, its a matter of randomizing the orientation of the magnetic dipole. Heres what you do: Key Takeaways: Demagnetization Demagnetization randomizes the orientation of magnetic dipoles.Demagnetization processes include heating past the Curie point, applying a strong magnetic field, applying alternating current, or hammering the metal.Demagnetization occurs naturally over time. The speed of the process depends on the material, the temperature, and other factors.While demagnetization may occur by accident, it is often performed intentionally when metal parts become magnetized or in order to destroy magnetic-encoded data. Demagnetize a Magnet by Heating or Hammering If you heat a magnet past the temperature called the Curie point, the energy will free the magnetic dipoles from their ordered orientation. The long-range order is destroyed and the material will have little to no magnetization. The temperature required to achieve the effect is a physical property of the particular material. You can get the same effect by repeatedly hammering a magnet, applying pressure, or dropping it on a hard surface. The physical disruption and vibration shake the order out of the material, demagnetizing it. Self Demagnetization Over time, most magnets naturally lose strength as long range ordering is reduced. Some magnets dont last very long, while natural demagnetization is an extremely slow process for others. If you store a bunch of magnets together or randomly rub magnets against each other, each will affect the other, changing the orientation of the magnetic dipoles and lessening the net magnetic field strength. A strong magnet can be used to demagnetize a weaker that has a lower coercive field. Apply AC Current One way to make a magnet is by applying an electrical field (electromagnet), so it makes sense you can use alternating current to remove magnetism, too. To do this, you pass AC current through a solenoid. Start with a higher current and slowly reduce it until its zero. Alternating current rapidly switches directions, changing the orientation of the electromagnetic field. The magnetic dipoles try to orient according to the field, but since its changing, they end up randomized. The core of the material may retain a slight magnetic field due to hysteresis. Note you cant use DC current to achieve the same effect because this type of current only flows in one direction. Applying DC might not increase the strength of a magnet like you might expect, because its unlikely youll run the current through the material in the exact same direction as the orientation of the magnetic dipoles. You will change the orientation of some of the dipoles, but probably not all of them, unless you apply a strong enough current. A Magnetizer Demagnetizer tool is a device you can purchase which applies a strong enough field to change or neutralize a magnetic field. The tool is useful for magnetizing or demagnetizing iron and steel tools, which tend to retain their state unless disturbed. Why You Would Want to Demagnetize a Magnet You may be wondering why youd want to ruin a perfectly good magnet. The answer is that sometimes magnetization is undesirable. For example, if you have a magnetic tape drive or other data storage device and wish to dispose of it, you dont want just anyone to be able to access the data. Demagnetization is one way to remove the data and improve security. There are many situations in which metallic objects become magnetic and cause problems. In some cases, the problem is that the metal now attracts other metals to it, while in other cases, the magnetic field itself presents issues. Examples of materials that are commonly demagnetized include flatware, engine components, tools (although some are intentionally magnetized, like screwdriver bits), metal parts following machining or welding, and metal molds.
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