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[Jan. 8th, 2007|10:29 am]
The little engineer that could
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The purpose of crop farming is to replace a mixed population of trees, plants and grasses with a dense population of a single species such as wheat or beans. In a monoculture, a single crop is permitted to grow, while competing plants are destroyed along with organisms that may infect or feed on the cultivated crop. Agriculture may be seen by some as the opposite of monoculture, but scientists are beginning to recognize the problems surrounding this method of farming.
Farmers have worked to reduce genetic biodiversity between crops through the use of plant breeding and cloning. Reduced biodiversity has been considered favourable as it is ensures consistency and predictability. Crops grow at the same time, produce identical fruit and have higher chance of successfully harvesting.
Unfortunately, such actions force the balanced ecosystem to split, displacing plants and animals to small areas. In order to sustain a rich variety of wildlife, it is vital to carefully plan the balance between the amount of land used for agriculture, roads, or other human inhabiting. Agriculture has destroyed many natural habitats for animals. Many hedges which support wild plants and provide a nesting and feeding area for birds and animals have been wiped out in favour of larger fields. This has had adverse effects on many species of insects, flowers and birds.
One historical example of the danger of monoculture is the Irish Potato Famine of the 1800’s. The Irish of this century managed to feed a growing population with potato farms consisting of identical potatoes, lacking any genetic variability. The potatoes were devastated as soon as a change in environment occurred and a potato disease struck the country. Had the potato farms been sown with genetic variability, there would have been some potatoes with the genes to resist the disease, and more of this sort could have been planted during the next season.
Such effects can be diminished by leaving strips of uncultivated land around fields or by planting new hedges. The “unproductive” land can prove valuable if it is utilized to provide refuge for insects in the winter, as well as shelter, food and nesting grounds for mammals, birds, amphibians and reptiles. Strips of wild plants between fields can be a great help to the population of beneficial insects. For example, the placement of phacelia around wheat fields can control the aphid population by providing a nesting ground for hover flies, the aphid’s predator. Another method is to sow a strip of grass in between fields in order to provide a warm shelter for predatory beetles.
Additionally, there is increasing recognition for the need to maintain diversity within a single species. Genetic diversity within a species is very beneficial to its health, possibly crucial to the maintenance of endangered animals. Encouraging such diversity may also be very helpful in the breeding of new crops and livestock.
Species of all kinds have roles within the ecosystem. Species can perform different functions, such as obtaining and storing energy, production, decomposition, distributing substances, guarding against threats, or regulating the climate. A diverse ecosystem is therefore significantly more stable, healthy and productive than a monoculture. The departure of a single species may hinder the ecosystem in its ability to maintain stability and recover from disturbances seeing as the room for adaptation is very small in a monoculture.
Species work together to form an interwoven web, where many species are reliant on each other. Many different kinds of plants are necessary in order to feed a variety of different animals, and many species require a variety of food sources in order to obtain all the nutrients necessary for a healthy diet. Plants also serve as homes and shelter for many species, and mean more than just a source of food to maintain the food chain.
Due to the nature of monocultures consisting of single species and continuing through repeated planting, vulnerability to insect attack and disease is high. Pesticides are often used to combat such threats, destroying both pests and competitors such as weeds. Herbicides are used to destroy plants which compete for root space, soil minerals and sunlight while fungicides protect against fungus and insecticides destroy insects which may cause damage to the crop. The downside to pesticides is that they can kill beneficial as well as harmful organisms. For instance, bees are helpful in pollinating flowering plants while ladybirds eat aphids.
Predatory animals and insects can be a valuable natural alternative to pesticides. Many farmers are moving away from the use of pesticides that they were once so reliant upon, in favour the biological method for destroying pests. Benefits of using these new methods include a cleaner image and reduced. Biological control is much easier to maintain, as it is self-sustaining and removes the problem of pests developing resistance to pesticides. Biological control also eliminates the risk of pollution and human reaction to harmful pesticides.
Unfortunately, biological control of pests is not always completely functional. When insects are introduced to crops by human means, they may be slow to spread, reproduce, and adapt. For this reason, it is far more effective to enhance and encourage predatory species which are already present in an environment.
Useful predators include ladybirds and other beetles, flies, and parasitic wasps. The naturally occurring population of these predators is too low to provide ample control of pests, as they are also sensitive to pesticides and require abundant resources in order to reach high population. Their use can be more easily exploited when pesticides are reduced or only microbial substances are used. They can be encouraged to grow in population by providing pollen and nectar bearing plants, shelter, and alternative prey to feed on during periods when pest density is low.
Yet another benefit to biodiversity is to provide alternative food sources for pests, detracting them from crops. For instance, the Nezara viridula is a major pest to sweet corn, which sucks out the juice and discolours the crop when it feeds on it. The bug is resistant to pesticides, but farmers have solved this problem by planting mustard seed around corn fields, attracting the pest away from corn itself.
Due to the inconsistency of the world’s climate, biodiversity is necessary to maintain the environment. Chemicals die and regenerate constantly throughout the year to provide a steady supply of food for various organisms. For instance, certain bacteria emit nitrogen, while others reduce or convert nitrogen, providing nutrients for plants. These organisms work together to produce healthy crops, while other organisms keep the bacteria from overpopulating by feeding on them.
In Sweden, the most biodiversity found in agriculture is among the hay meadows. These can hold as many as fourty different species of plants within a single square meter. Hay-making allows many plants to grow which require a great deal of light but grow low to the ground. The practice of hay-making has caused a genetic change in that many plants are beginning to flower earlier in the year. Many of the plants that live in this environment can adapt to a lack of nutrients by living in symbiosis with the aforementioned nitrogen-producing bacteria.
In conclusion, biodiversity is valuable for many reasons. It provides a variety of resources for plants and animals, including humans. It ensures a selection of food and tools. Many species and their biological processes are required to maintain the environment, including the composition of the atmosphere, soil formation, temperature, precipitation, and radiation levels. |
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| (no subject) |
[Sep. 30th, 2006|10:44 am]
The little engineer that could
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The behavior of many non-linear dynamical systems as a function of time is found to
be chaotic. The characteristic feature of chaos is that the system never repeats its past
behavior. Chaotic systems nonetheless obey classical laws of motion which means that the
equations of motion are deterministic.
PoincarÈ was the first to study the effects of small changes in the initial conditions
on the evolution of chaotic systems that obey non-linear equations of motion. In a chaotic
system, the erratic behavior is due to the internal, or intrinsic, dynamics of the system.
Let a dynamical system be described by a set of first-order differential equations:
dx/dt = f (x,x,x,...x ) (11.1)
1 1 1 2 3 n
dx/dt= f(x,x,x,...x )
2 2 1 2 3 n
. .
. .
dx /dt= f (x,x,x,...x )
n n 1 2 3 n
where the functions f are functions of n-variables.
n
The necessary conditions for chaotic motion of the system are
1) the equations of motion must contain a non-linear term that couples several of the
variables.
A typical non-linear equation, in which two of the variables are coupled, is therefore dx/dt= ax + bx + cxx + ... rx , (a, d, c, ...r are constants)
1 1 2 1 2 n
and
2) the number of independent variables, n, must be at least three. |
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| (no subject) |
[Sep. 21st, 2006|10:29 am]
The little engineer that could
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Toni Terling Watt Ph.D, Are Small Schools and Private Shools Better?, Sociology of Education 2003, Vol. 76 (October): 344–367
9. The research question: Are smaller schools more beneficial for a child’s emotional development?
10. Dependent variable: Mental health (as defined by depression, eating disorders, substance abuse, suicide and violence). The regression scoring method was used to produce a single score from these items.
Independent variables: Small schools, Large schools. This information was obtained by school administrators and processed from administrative datea. Small schools were defined with less than 400 students, medium with 401-1000 students, and large with over 1001 students.
Control variables: Different types of schools are likely to have different socioeconomic status. Groups were divided into measurements of parents’ education and income levels. Whether the children had one mother and one father was also measured. Race was measured. Neighbourhood variables were divided into urban, rural or suburban. Family relations were measured by asking the students to rate how stongly they agree with statements such as “My parents care about me.”
Comparative hypothesis means no spurious variables.
11. The sociologists have used quantitative research methods, emphasizing comparisons in measurements, surveys and statistics, also using qualitative research methods as the answers to survey questions were interpreted and quantified.
12. The major hypothesis: Large schools lack individual attention and a sense of community, thereby promoting healthy social and psychological development.
13. Sampling techniques: 13,000 adolescents grades 7-12 were selected from the National Longitudinal Study of Adolescent Health.
14. Data-gathering/data-collection techniques: Data was gathered with private, independent questionaires throught the use of computer interviewing. This was selected to increase comfort in responding to sensitive, private questions. The students were interviewed from 1994-1995 and then interviewed once again one year later. The study therefore includes the outcomes from the first interview and the effect they may have on the second interview.
Questions were asked such as when they felt sad, lonely, depressed or helpless; how many times they had attempted suicide; and how many times they had used a weapon to threaten or attack someone.
15. Data analysis: Mean estimates and standard deviations were used to present the information separately for males and females. As expected, females reported higher levels of depression and suicide rates while males reported higher violence. The cluster sample was processed with unequal probability.
16. Sources: Department of Sociology, Texas State University, San Marcos. |
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| (no subject) |
[Sep. 6th, 2006|10:29 am]
The little engineer that could
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Idag, den vedertagna teorien som förklarar fenomenet evolution är känd som ”det naturliga urvalet.” Denna teori visar att det finns diversitet inom varje art så att vissa individer inom en art har förmågan att anpassa sig och överleva mer än andra individer. En individ som överlever i en längre period kommer troligen att reproducera men en som inte lever så länge har inte så mycket chans att få barn. Eftersom ättlingen ärver de gener som medgav att föräldrarna kunde leva så länge kan ättlingen själv leva en långt liv och få många barn själv. På detta sätt har gener större sannolikhet att bli utbredda från en organism som lever länge.
Det naturliga urvalet befrämjas konkurrens, både mellan arter och såväl mellan indvider inom samma art. Organismer tävlar om tillgångar, skydd, och andra organismer att para sig med, så bara de som är vid mycket god hälsa och har bra förmåga att anpassa sig kan överleva och föda upp. Några exempel på hur en djur kan vara välanpassad är förmågan att springa från rovdjur, smälta mat, eller reproducera mycket. Eftersom sådana organismer överleva kommer de föda generation som är snabbare, friskare och fruktsammare. Det naturliga urvalet funkar självklart bara med arvsanslaget. Erfarenhet kommer kankse få en organism att bli moståndskraftig mot bistert klimat, att ha starkare muskler eller att springa snabbare, men sådana drag stödjer inte det naturliga urvalet om de inte kommer från gener.
Björkmätaren tillför ett bra exempel på det naturliga urvalet. Denna mal har både ljusa och mörka slag. År 1850 var den mörka slag ganska sällsynt men efter bara fem år var nästan hela art det mörka slaget. Teorien är att det mörka slaget döldes från rovdjur när de vilade på träd eftersom förorening fick trädstammar mörkare och mörkare. Av denna avledning dog de ljusa malar så bara de mörka malar fortplantade sig så deras gener gick i arv.
Ett intressant exempel på det naturliga urvalet är sjukdommet sickle-cell anemi. En människa har sickle-cell anemi när han eller hon har två alleler (en från modern och en från fadern) som bär den bristfälliga genen. Denna gen påverker hemoglobinet och förstör röda blodkroppar vilken leder till en kortare livslängd. Man kunde förvänta att sådana gener skulle vara utvald från befolkningen men genen stannar kvar därför att den är fördelaktig för man som har den i heterozygot form. Man som har bara en sickle-cell allel ett fåtal sickle-cell röda blodkroppar vilken hjälper att skydda mot malaria. Av denna anledning är sickle-cell anemi mycket sällsynt i områden som inte drabbas av malaria.
Teorin för det naturliga urvalet kom från två faktum. Det första faktumet är att alla organismer reproducera så snabbt att befolkningen skulle bli extremt stor om reproduktionen balanserades inte av mortalitet. Det andra faktumet är att organismer är variabla och drag går på arv från en generation till den nästa. Man kan observera att diversitet bland drage påverkar hur organismer klara sig i miljön och underhåller sin befolkning.
Organismer med egenskaper som är bättre anpassade har större sannolikhet att ge välgörande gener till ankomman. Det var Charles Darwin som kallade fenomenet ”det naturliga urvalet” på 1800-talet. Det är avjort idag att de skilda egenskaper bland alla organismer utveckla på grund av det naturliga urvalet. Man kan definiera att det naturliga urvalet är vad som klassifera något som levnad.
Det naturliga urvalet kan åstadkomma en mångfald olika resultat att ske. Det kan bevara befolkningen i det innevarande tillståndet och underhåller vad som är redan normalt inom arten. Det kan även ändra egenskaper åt ett håll om vissa individer ha en fördel jämfört med allmänheten. Det kan också ändra egenskaper åt olika håll om varierande egenskaper är fördelaktig.
Om organismer med extrema drag, till exempel de minsta och de största i befolkningen, reproducera i lägre fart än genomsnittliga individer kommer befolkningen att stabiliseras. På så sätt kommer befolkningens variabilitet att minskas. Sådan förekommer ofta som står i kontrast till biodiversitet som är föranledd av mutation och migration. Denna stabilisering kan betydligt sakta evolutionfarten vilken är bekräftad från fossilundersökningar.
Ett exempel på stabilisering visas med svalor från Nebraska i USA. När Nebraska drabbades av strängkyla 1996 dog ungefär hälften av svalor på bara sex dagar. Biologer undersökte fåglar som överlevde och upptäckte att de överlevande var i genomsnitt större och mer symmetrisk än de som inte överlevde. De största fåglar överlevde troligen därför att de kunde lagra mer späck och de symmetriska fåglar hade det lätt att fånga rov. Miljön fick att de kunde inte växa för stora så den korta klimatförändringen resulterade i en stabilisering av befolkningen.
En andra sorts naturligt urvalet sker när ändringar driver åt ett extremt håll, till exempel när genomsnittsstorleken bli större. Denna sorts evolution kan förtsätta med många generationer och organismerna får större och större avkomma, men fenomet kan vridas tillbaka om miljön ändras. Det kan annars avstyrs om den idealiska storlek nårs, och vid denna tidpunkt sker stabilisering.
Det finns en trejde sorts naturligt urval som är ganska sällsynt. Den händer när två olika ytterligheter är fördelaktiga. Den här är motsatsen till stabilisering eftersom genomsnittliga individer reproducera inte så mycket som extrema individer. Näbbstorlekar på purpurastrilder, en sorts fink fågel, visar effekterna av det här urvalet. Den vanligaste maten för den här fågeln är säden två sorts sumpväxter. En fågel med en stor näbb kan knäcka säd från en sorts sumpväxt och en fågel med en liten näbb kan den mjuka säden från den andra sorts. En fågel med en genomsnittlig näbb skulle ha det svårt att äta båda sorts säd och således finns det en tendens för antingen mycket stora eller mycket små näbbar inom befolkningen.
Ett intressant resultat av det naturliga urvalet är osjälviskhet. Det finns en evolutionsfördel för individer inom en art att vara altruistisk mot de som är genetisk likadana de själva. Sådana genetiska fördelar gagnar inte individen men hjälper att underhålla hela den arten. Det är sant i synnerhet när organismer hjälper släktingar eftersom släktingar har många likadana gener. Ett exempel på det visas mycket klart med biätare, en afrikansk fågel. Dessa fåglar hjälper varandra kläcker ägg och föder sina ungar. Nästan hela tiden hjälper fåglarna de närmaste anhöriga istället av avlägsna släktingar. Det här kan bara vara ett exempel på osjälviskhet därför att fåglarna får ingenting själv från att hjälpa andra fåglar. Det finns även vissa organismer, till exempel myror, bin, getingar och termiter, med hjälpsamma individer som inte kan reproducera själva. Sådana individer kan bland annat skyddar från rovdjur eller hämter mat till andra individer.
Ömsesidig osjälviskhet sker mellan individer, ibland mellan två arter. Det naturliga urvalet tillförsäkrar att arter har större sannolikhet att överleva som ett grupp om de till exempel ger varningar till varandra eller delar mat. Det är ganska synbart att sådan sorts osjälviskhet råder inom den mänskliga arten. |
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| (no subject) |
[Jul. 19th, 2006|10:37 am]
The little engineer that could
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The indigenous people of Scandinavia, known as the Sami, sometimes known to themselves as “the people of the sun and wind” inhabit the northern regions of Finland, Norway, Russia and Sweden. The Samis have an estimated population of 50,000 and live from reindeer herding, hunting, fishing and agriculture. They have lived in harmony with the harsh climate of Northern Scandinavia for thousands of years. Unfortunately, the exploitation of their land and natural resources has threatened the Sami way of life.
The Sami have a rich and inspired tradition of oral poetry, but the protest of the damming of the Alta River in Norway has represented a turning point after which their creativity in political literature has blossomed. Traditional Sami literature was comprised of yoik, or “songs” and muitalandaidu, or “tales.” Much of this literature was not even considered to be Sami, but something that was “picked up” by other cultures.
The yoik was a song of rebellion, similar to the blues. It was originally exclusive to the shamans, but went underground when a Danish king banned the yoik on punishment of death. With pre-Christian elements, the yoik told of mysterious creatures such as stalu (giants) or gufihtar (trolls). They were often improvised as self-expression, to keep the wolves in the herd, or as a lullaby. Many yoiks had double meanings, in order to communicate hidden messages. Comparisons and metaphors were used to communicate openly with other Samis, but without the understanding of colonizing people, allowing them to express opinions and facts which may have been dangerous to reveal. Sometimes they may go so far that a visitor would not realize they were being mocked. This was a powerful tool for the Samis to resist assimilation.
More recent literature has a contemporary class of its own. Modern Sami literature has been heavily influenced by massive changes in Sami life and social structure during World War II. The artistic revival following the social crises is marked by moving, sad poetry and artwork. A major theme is the conflict between the culture of nature and the industrialized world. Samis are finding their sense of identity torn between their traditional ways and the call of modern life.
Contemporary Sami literature is often composed to tell of how it is to be a Sami as compared to industrial life. Many Samis feel that the Swedish government does not understand Samis, so literature is sometimes used to communicate the Sami perspective to political institutions. Johan Turi, a pioneer in the field of Sami literature states that this is because a Sami doesn’t feel well in an enclosed government meeting space, but can only think clearly when out in the hills with “the wind blowing in their nose”.
Turi chose to write his book as an autobiography, an original way to make a political statement and the first of its kind. The book allows him to demonstrate the feeling of self in relation to dominant cultures, forming a new path between the Sami oral tradition and contemporary literature. This link provides a means to relate Sami traditional pieces to other cultures as well as closing some gap between Sami oral literature and Scandinavian written literature. Turi had hoped to write the definitive book on what it is to be a Sami, to help solve legal conflict regarding his people and to let people understand the Sami way of life. Originally intended only for Swedish legislators, his book Muittalus Samid Birra: en bog om lappernes liv (titled Turi’s book of Lappland in English) had tremendous success in helping an unexpectedly large audience understand the Samis.
In addition to writing of the need to preserve the Sami identity in the face of dominant cultures, Samis often write activist literature concerning nature. Samis are often compared to Native Americans, sharing the intimacy with nature, and regarding natural forces as something to be deeply respected. Samis feel that industrialized cultures are doing great wrong in exploiting nature like a resource capital. Paulus Utsi (1918–75) from Jokkmokk, one of the most successful Sami writers, tells grim poetry about the “strangers” who exploit their beloved Arctic land. These two prevailing themes are bitterly portrayed in Sami literature, giving us insight into the nomad’s way of life and integration with nature.
Many Samis don’t know their modern tongue, and many of those who do are illiterate. Only the northernmost population speaks Sami at all. There are few who speak Sami, making the market for Sami literature very small. There are so few readers of Sami that a book must be subsidized to produce Sami literature in the original language in order to cover its costs. This is why Sami writers feel it so important to reinforce the Sami language, preserving its history, culture, perspective and way of life. The use of Sami as the language of choice represents a political statement for many Sami writers who would be capable of writing in a majority language.
As the writer Veli-Pekka Lehtola tells us, a small language is weak and defenseless, “like a small fox, unprotected by the pack.” A piece written in an obscure language is very easy to distort, to be changed in the translation and difficult to preserve. It is easy to be subsumed by a majority language. For this reason, many Samis have taken to writing in major Scandinavian languages and in English, so they may reach a larger audience – as well as to reach other Samis who have lost their home language to the dominant western paradigm.
A Laguna-Pueblo writer, Leslie Marmon Silko criticizes translators from minority to majority language. Her point of view is that this “translation” is just pretense. She points out that most translators of minority languages are actually not conversational in these languages, so what they are really doing is rearranging ethnological transcriptions rather than translating. Much of the original content is likely to be distorted after a translation, bringing in the new language’s presentation and context.
Which language a Sami writer should use in modern day writing is a highly charged conflict. In choosing Sami, the writer makes a statement, preserves their own culture and can write more freely in their culture’s own voice. The downside is that the writer will reach a much smaller audience, be open to interpretation in translation and have less control over the final product of their published book. This is why some Samis are choosing to write in a major Scandinavian language or in English, allowing them to reach a wide audience, including those they wish to protest against, opening up a discussion to a whole country or region.
The subject of context is not only a concern regarding the language. There is a tendency for people to read alien literature in their own culture’s context, using their own culture as a yardstick to judge another. Readers can be very quick to see the work of indigenous peoples as primitive, or they may otherwise stereotype them within terms that are familiar to their own culture. They may romanticize them, projecting their own connotations over the original, intended meaning. It is often very difficult to be able to see literature from an unfamiliar culture within the unwritten framework intended by the author.
Stories have traditionally been the focal point of a Sami education. The basis of the Sami educational system was not about tests and competition, but a telling of stories. The Samis learned their history, culture, values and skills through storytelling. These stories were a part of everyday life, being told while they performed their daily work. Everyday life and storytelling were holistic, with no boundary drawn between the arenas of the ordinary and the academic. Marginalized societies often give a large significance to literature. Stories open up an avenue to communicate important matters to the outside world at a lack of other opportunities to do so.
Storytelling, however, is fading in Sami culture. Hugh Beach, an author who spent a year with the Sami tells that this is happening because the audience is growing smaller. Storytelling was the traditional way in which Samis communicated knowledge. Storytelling was a way to share diehtu (knowledge from experience) and dieda (scientific knowledge). Unfortunately, according to Turi, Sami writers sometimes find themselves mocked by other Samis for spending their time doing work that will produce no bread. Sami stories have definitely changed in both content and context.
We of dominant cultures can learn from Sami literature. The Sami tales can teach us about nature, tradition and incorporate genres of today and yesterday. The beauty of the Sami literature tells of our humanness in connection with nature. |
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| (no subject) |
[Jun. 10th, 2006|10:27 am]
The little engineer that could
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Kulramen var uppfunnen i Babylon 3000 talet tror vi. Några människor använder det fortforande. Om man är duktig med det är det snabbare än en kalkylatör. Det är också bra för blind människor. Den första mekaniska kalkylatör uppfinnades 1600-talet.
1840-talet – Ada Lovelace. På den tiden fanns det en kvinnorsbefrielserörelse och hon var medlem med The Bluestocking Society som var en institution för att utbildar kvinnor. Hennes mor var en matematiker som lämnade fadern när Ada var en månad gammal efter han fuskade. Så hon fick chans att få utbildning och hennes mor var mycket strikt med henne därför att hon vill inte att Ada ska vara en poet likadan sin far. Så hon insisterade att hon ska lära sig att vara logisk och var undervisad i matematik och musik.
Hon var jättebra med matematik men gillade inte det och ville plugga bara geographi. När hon var 13 gjorde hon en ritning till ett flygplan.
Och när hon var en tånare var det svårt att hitta en lärare därför att hon visste mer än dem! Men då träffade hon Mary Sommerville som hade lärt sig matematik själv i hemlighet.....och hade gjort väldig mycket för astonomi. Och hon tog Ada under hennes vingar.
En maskin var gjord av Charles Babbage som hon såg när hon var 17 och bestämde sig att skriver programspråket till det. Hon använde ”punch cards,” kort med mönster av håller som var användt i de mesta dator tills 1970-talet. Babbage, som konstruerade maskinen kallade henne ”The Enchantress of Numbers.”
Hon är en stor karaktär i bocken The Difference Engine....handlar om om maskinen hade varit massproducerad och Data Åldern hade börjat i den tiden.
I 1930-talet använde man analog datorer. Så det fanns fortfarande inget datorprogram. Men det fanns Vattenintegratör i Ryskland. Det fanns rör av vatten och hur mycket vatten var i röret representerade ett nummer. Det kunde lösa differentialekvationer.
Den första digital datorer kom under Andra Världskriget. De använde punch cards. Det fanns många nya datorer från USA, England och Tyskland. Brittiskar uppfinnade en dator som kunde hindra tyska signaler.
En serie datorer Mark I-III var konstruerad av marinen som sägs var början av alla modern datorer. Grace Hopper utvecklade programspråket till det. Med Mark I fanns det ett problem och det stängde av sig själv varje några sekunder. När amiraler kom för att undersöka datorn lutade hon mot datorn och höll fingern på knappen för att hålla det på.
Och om ni vet ordet ”bug” (explain) Det kommer från Mark II. En mott hade krupit i en krets.
Hon skapade datorprogramspråket COBOL senare som var det första programspråket där man kan pratar med dator med ord, inte bara nummer.
1970-talet, Steve Jobs och Steve Wozniak ville skapa datorer som vanliga människor kan har i sitt hem. Woz arbetade för HP ....de hatade det...
De säljde det själv ur sin garage. Det hade 16k RAM och man använder TV-apparaten som skärmen. När de presentade det på en datormässa var det en fenomenal succé.
Under mellantiden, Bill Gates hittade att IBM behöver program så han skrev ett programspråk som heter Altair BASIC och var den första programspråket för en massproducerad persondator och var den första produkt av Microsoft. Microsoft BASIC blev det största programspråket i världen när IBM använde det på IBM PC-n i 1981.
Men IBM behövde något annat. Tim Paterson skrev DOS, den första operativesystemmet. Han blev mycket rik från den där därför att han insisterade att han kan behålla licensen till dem.
-Picasso......Bra artister kopierer. Underbara artister stjäler. |
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| (no subject) |
[Mar. 13th, 2006|10:25 am]
The little engineer that could
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Fetma är ett tillstånd i vilket fett är förvarad i mycket högre mängder än vanligt och börjar att innebära ett problem för hälsan. Fetma kan ha flera olika orsaker. Det kan bero på genetisk disposition, en högenergi diet, en brist på motion, en ätstörning, och/eller stress.
Nuförtiden har vi en epidemi av fetma. Vi antar att det är så därför att förr i tiden var föda knapp så man behövde äta allt som man kunde och att ha lite extra fett var välgörande. Nu finns det en överflöd av föda och många rör sig inte mycket så kroppen blir för fet.
I USA är problemet värst. Detta är pga. flera orsaker. Under gångna årtionden så har priser på mat som är rik på socker och fett gått ner. Eftersom minimilöner inte har stigit med inflationen har många inte råd att köpa hälsosam mat. Marknadsföring bidrar också mycket. På 80-talet tog man borta begränsningar för att annonsera till barn, så många mattillverkare, t.ex McDonalds och Nabisco, gör allt som de kan för att få barn på kroken. Zonlagar och en brist på trottoarer gör det omöjligt att promenera så man rör sig mycket mindre.
Vad är svaret till det här problemet? Det är inte lätt. Att göra motion lättare att hinna med och roligare skulle hjälpa. Att göra hälsosam mat lättare att hitta och billigare att köpa vore bra. Jag tror att den bästa saken att man kan göra är att lära ut bra vanor till barn så de äter bra och rör sig hela livet. |
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| (no subject) |
[Feb. 5th, 2006|10:29 am]
The little engineer that could
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Psychoanalysis. In the early 20th century, most theorists occupied themselves with the study of consciousness and biological determinants in behavior. Freud introduced the idea that human beings are also motivated by the unconscious. Freud recognized the importance of biology in behavior, which he referred to as instinct, a need or desire which could be physical (hunger, sexual arousal) or emotional (guilt, the need to be liked). According to Freud, disorders and harmful behaviors come from a clash between instincts or the inability to release one’s emotions.
One example of a Freudian perspective may be when a child knocks over the block construction his friend is making with another child, which could be interpreted as him acting out the jealousy he feels indirectly. Another may be if a person channels all her energies to work, to transfer the drive she feels to pursue an instinctive need.
There are many controversies surrounding Sigmund Freud, as demonstrated by the popular nickname, “Sigmund Fraud.” If we wish to turn to the evidence, we find there is very little research to support Freud’s theories, partly because it is very difficult to test. There is also an aversion by some to accept the idea that human beings, like other animals, do not always act as the result of a conscious decision. Still, Freud’s ideas, though still only theoretical, have had an enormous influence on the field of psychology and provide the building blocks for many newer theories used today.
Sources: Understanding Children and Adolescents, Schickedanz
Depression Central, Dr. Ivan Goldberg
Why Freud was Wrong, Richard Webster
Behaviorism. An American psychologist, John B. Watson (later championed by B.F. Skinner), was the first to disagree with Freud by introducing the behavioral approach. Watson believed that it was not the human psyche, but the environment which determines human behavior. This is the idea that all our thoughts, feelings and actions are a result of conditioning from various stimuli external to ourselves. The first experiments which Watson drew upon to support his perspective were Ivan Pavlov’s, in which dogs were taught to salivate at the sound of a bell.
The most widely used example of behaviorism is how parents use rewards, such as gold stars or praise, combined with punishments, such as time outs or groundings, to reinforce positive behavior.
The positive/negative reinforcement techniques have been shown to be very effective in the education field as well as in treatment of disorders, especially autism and antisocial behavior. Still, there is no shortage of criticism against behaviorism which, like Freudian ideas, asserts that the human mind does not always (or perhaps not ever) think for itself. There is also some learning, such as the ability to absorb new language patterns by children which does not seem to be explained by behaviorism. There has been research which shows animals adapting to new information, such as when a rat responds to a change in a maze originally learned by reinforcement.
Sources: Understanding Children and Adolescents, Schickedanz
Perspectives on Learning, D.C. Phillips
B.F. Skinner, Skinner on Behaviorism
Humanism. Carl Rogers was a major force in the argument against behaviorism. Rogers provides an optimistic viewpoint, that we have control over our own mind, that although we are influenced by our environment, we have the ability to make our own individual conscious decisions. Rogers made a major change in therapy when he presented the idea that it is the client who knows best what the problem is, what is the most important problem and how to solve the problem.
An example may be a black person in a time when they were constantly conditioned by society to be subservient, but still decided to stand up and fight for her rights.
There may be more to the humanistic perspective than I understand at this level, but to me, it seems like a “mystical” rather than scientific explanation. Although there is not necessarily anything wrong with a spiritual idea, in science, we must be more conservative and consider cause and effect. If somebody has a thought or a feeling, it must have a source. I fail to see how one could take an action if it was not driven by a desire and a desire is not something that a person can choose. I also don’t see how a decision can come from nowhere. If a thought comes into a person’s head, then I can see it coming from biology, from the environment or a combination of the two. As far as I can tell, the humanistic perspective proposes that thoughts just “happen” without any cause. This may be explained further and make more sense when we move past the introductory level. |
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| (no subject) |
[Feb. 2nd, 2006|10:37 am]
The little engineer that could
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There are two schools of thought about how religion is connected with social order. One theory is that religion is simply a reflection of society, while others argue that religion is a central force in society. The reality is most likely cyclical, but I am going to explore the idea that religion (or lack thereof) influences a society’s condition.
The protestant belief system encourages individual achievement and financial success. The belief is that wealth and achievement are signs that a person is in God’s favour and destined for heaven. The desire to make money appears to correlate with a Protestant ethic as capitalism consistently prevails in Protestant countries. Protestantism flourishes in the USA, with 35% of the population being Protestant as well as every single president except Kennedy. Although few Americans are still so extreme as to believe success comes only from God’s approval, the values of personal achievement and the idea that the poor are at fault has permeated American culture.
In contrast, the Swedish Lutheran religion values modesty, sense of duty to the group and inconspicuous behavior. This is likely to be connected to the Swedish passion for equality. One person excelling and fighting for achievement more than the rest of the group is looked down upon. The religion favours the group over the individual, which is very likely to have played a part in the drive for social welfare and equal position. The puritanical dogma keeps its members from drawing attention to themselves, breaking rules or rocking the boat.
One of the most remarkable phenomenons in Sweden is how rapidly it has changed in the last century. At the same time, Sweden has been breaking away from religion. In less than a century, Sweden has gone from a highly religious country to one of the world’s most secularized countries. It is not common for a country to experience so much change and reform in such a short time. The pace that Sweden has been changing may be connected to secularization. Only 4% of Swedes attend church regularly, as compared with 43% of Americans. Religious people are often heard using the word “tradition.” A highly religious country such as the USA is likely to maintain traditional values and politics as dictated by the religion. When a person follows a religion, they tend to have set beliefs that do not change. As Sweden is more secular, it makes sense that they would be more likely to question the old ways and consider new options more readily. When one does not question religion, they are most likely not going to question the government, either.
The Journal of Socio-Economics shows some interesting studies on the effects of secularization. Secularization is correlated to higher rates of children born out of wedlock, which is consistent with Swedish compared to American statistics. It may also be possible that secularization plays a part in Sweden being the #2 country for the highest divorce rate, with other factors contributing to the USA being #1. The secularity of Sweden is likely to also be responsible for the younger age that teenagers start having sex. Fortunately for Swedes, the sex education does not involve the religious abstinence education found in the US, resulting in pregnancies four times more likely for American teens. Unlike Sweden, there are many, many large demonstrations promoting hate towards homosexuals or women seeking abortion.
Finally, and most simply, conservatism is likely to be more common in the US because it is a highly religious country. Studies have shown religion to be correlated with conservatism. Anti-abortion, anti-union, anti-environment, forbidden premarital sex, pro-war, pro-traditional family and pro-corporal punishment are all ideas likely to be found with churchgoers. They also happen to be ideas far more prevalent with Americans than with Swedes. |
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