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Mostrando postagens com marcador internet. Mostrar todas as postagens
Mostrando postagens com marcador internet. Mostrar todas as postagens
07 agosto 2013
Compras on-line e congestionamento
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19 julho 2013
21 junho 2013
Internet para todos
The Internet is one of the most transformative technologies of our lifetimes. But for 2 out of every 3 people on earth, a fast, affordable Internet connection is still out of reach. And this is far from being a solved problem.
There are many terrestrial challenges to Internet connectivity—jungles, archipelagos, mountains. There are also major cost challenges. Right now, for example, in most of the countries in the southern hemisphere, the cost of an Internet connection is more than a month’s income.
Solving these problems isn’t simply a question of time: it requires looking at the problem of access from new angles. So today we’re unveiling our latest moonshot from Google[x]: balloon-powered Internet access.
We believe that it might actually be possible to build a ring of balloons, flying around the globe on the stratospheric winds, that provides Internet access to the earth below. It’s very early days, but we’ve built a system that uses balloons, carried by the wind at altitudes twice as high as commercial planes, to beam Internet access to the ground at speeds similar to today’s 3G networks or faster. As a result, we hope balloons could become an option for connecting rural, remote, and underserved areas, and for helping with communications after natural disasters. The idea may sound a bit crazy—and that’s part of the reason we’re calling it Project Loon—but there’s solid science behind it.
Balloons, with all their effortless elegance, present some challenges. Many projects have looked at high-altitude platforms to provide Internet access to fixed areas on the ground, but trying to stay in one place like this requires a system with major cost and complexity. So the idea we pursued was based on freeing the balloons and letting them sail freely on the winds. All we had to do was figure out how to control their path through the sky. We’ve now found a way to do that, using just wind and solar power: we can move the balloons up or down to catch the winds we want them to travel in. That solution then led us to a new problem: how to manage a fleet of balloons sailing around the world so that each balloon is in the area you want it right when you need it. We’re solving this with some complex algorithms and lots of computing power.
Fonte: aqui
Fonte: aqui
18 junho 2013
Rir é o melhor remédio
Um dos cartoons mais famosos dos últimos tempos foi publicado na New Yorker. Mostrava dois cachorros conversando, um dizendo para o outro que na internet ninguém desconfiaria que eles seriam cães. Com a descoberta recente que o governo está espionando as pessoas, algo mudou:
07 junho 2013
Internet e o uso do carro
Longtemps, la voiture a été le symbole de la liberté individuelle aux Etats-Unis, immortalisée dans des road movies légendaires. Mais alors que les Américains ont toujours plus roulé pendant une période ininterrompue de soixante ans, le nombre de kilomètres parcourus a commencé à baisser depuis le milieu de la dernière décennie.
Les faits sont connus et ont déjà fait l'objet de recherches outre-Atlantique. L'argument économique y est régulièrement avancé. De fait, les conducteurs ont tendance à moins prendre le volant en période de récession, puisqu'ils travaillent moins et tentent d'économiser de l'argent. Surtout, le prix de l'essence a explosé depuis les années 1970.
Mais selon un nouveau rapport publié, mardi 14 mai, par l'ONG US Public Interest Research Group, cette thèse n'explique pas tout. Les modifications des habitudes de conduite ont en effet précédé la récente récession et semblent plutôt fairepartie d'un changement structurel lié à l'évolution démographique. Ainsi, selon l'étude, les jeunes sont moins susceptibles de conduire – ou même d'avoir un permis de conduire – que les générations précédentes, pour lesquelles la voiture s'apparentait à un droit.
LA FIN DU "DRIVING BOOM"
C'est ce que prouve toute une série de chiffres : alors que la distance parcourue par personne et par an est passée de 8 700 à 16 100 km entre 1970 et 2004 (+ 85 %), au cours de ce que le rapport appelle le "driving boom", elle a légèrement diminué entre 2004 et 2012, pour atteindre 15 000 km (- 7 %), soit le niveau de 1996. Autre preuve de ce recul : à la fin de 2012, les conducteurs représentaient 49 % de la population de plus de 16 ans contre 61 % lors du dernier sommet, en juin 2005.
A l'opposé, les Américains ont effectué presque 10 % de plus de déplacements en transports en commun en 2011 par rapport à 2005. Les déplacements à vélo et à pied ont également augmenté.
Cette tendance est encore plus marquée chez les jeunes : dans la tranche d'âge 16-34 ans, la diminution de l'utilisation de la voiture se monte à 23 % de kilomètres de moins en 2009 par rapport à 2001. Par ailleurs, de plus en plus de jeunes Américains n'ont pas le permis de conduire : ce taux est passé de 21 à 26 % entre 2000 et 2010 chez les moins de 34 ans.
TECHNOLOGIES DE L'INTERNET
"La génération née entre 1983 et 2000 est plus susceptible de vouloir vivre dans des quartiers urbains et piétons et s'avère plus ouverte à d'autres transports que la voiture que ses aînés, explique le rapport. Elle est aussi la première génération à adopter pleinement les technologies mobiles de l'Internet, qui offrent rapidement de nouvelles options de transport et peuvent même se substituer aux déplacements, grâce notamment au télétravail, au shopping en ligne, aux téléconférences et aux réseaux sociaux."
Cette étude corrobore des recherches menées en 2012 par Michael Sivak de l'Institut de recherche sur les transports de l'Université du Michigan, qui avaient déjà constaté que les jeunes obtiennent moins de permis de conduire que les générations précédentes. "La plus grande proportion d'utilisateurs d'Internet est associée à un taux d'obtention de permis plus bas, écrivait-il. Ce résultat est cohérent avec l'hypothèse que les contacts virtuels réduisent le besoin de contacts réels chez les jeunes."
Si le déclin de la conduite chez les jeunes se poursuit, selon le rapport du USPublic Interest Research Group, les taux de conduite aux Etats-Unis devraientrester en deçà du pic de 2007 jusqu'en 2040, même avec une croissance prévue de la population de 20 %.
Malgré cette évolution, la politique de transports américaine reste ancrée dans le passé, regrette le rapport. "Les prévisions officielles continuent de tabler sur une augmentation constante de la conduite, en dépit des chiffres de la dernière décennie, indique l'étude. Les politiques fédérales, étatiques et locales devraient au contraire contribuer à créer les conditions dans lesquelles les Américains peuvent réaliser leur désir de conduire moins. L'augmentation des investissements dans les transports en commun, les infrastructures cyclistes et piétonnes et le transport ferroviaire interurbain permettrait à davantage d'Américains de profiter d'un plus large éventail d'options de transport."
Fonte: Audrey Garric
19 maio 2013
A Internet trabalhando: Imagem estonteante
Por Nicholas Carlson
An anonymous researcher took control over some 420,000 Internet connected-devices in order to "map the whole Internet in a way nobody had done before."
The researcher came up with several beautiful still and moving images, including this .GIF, which shows where people around the world log-in to the Internet, and at what time.
An anonymous researcher took control over some 420,000 Internet connected-devices in order to "map the whole Internet in a way nobody had done before."
The researcher came up with several beautiful still and moving images, including this .GIF, which shows where people around the world log-in to the Internet, and at what time.
- Vermelho indica a maior quantidade de acessos -
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09 maio 2013
03 abril 2013
14 março 2013
Mensurando os benefícios econômicos da internet
When her two-year-old daughter was diagnosed with cancer in 1992, Judy Mollica spent hours in a nearby medical library in south Florida, combing through journals for information about her child’s condition. Upon seeing an unfamiliar term she would stop and hunt down its meaning elsewhere in the library. It was, she says, like “walking in the dark”. Her daughter recovered but in 2005 was diagnosed with a different form of cancer. This time, Ms Mollica was able to stay by her side. She could read articles online, instantly look up medical and scientific terms on Wikipedia, and then follow footnotes to new sources. She could converse with her daughter’s specialists like a fellow doctor. Wikipedia, she says, not only saved her time but gave her a greater sense of control. “You can’t put a price on that.”
Measuring the economic impact of all the ways the internet has changed people’s lives is devilishly difficult because so much of it has no price. It is easier to quantify the losses Wikipedia has inflicted on encyclopedia publishers than the benefits it has generated for users like Ms Mollica. This problem is an old one in economics. GDP measures monetary transactions, not welfare. Consider someone who would pay $50 for the latest Harry Potter novel but only has to pay $20. The $30 difference represents a non-monetary benefit called “consumer surplus”. The amount of internet activity that actually shows up in GDP—Google’s ad sales, for example—significantly understates its contribution to welfare by excluding the consumer surplus that accrues to Google’s users. The hard question to answer is by how much.
Shane Greenstein of Northwestern University and Ryan McDevitt of the University of Rochester calculated the consumer surplus generated by the spread of broadband access (which ought to include the surplus generated by internet services, since that is why consumers pay for broadband). They did so by constructing a demand curve. Say that in 1999 a person pays $20 a month for internet access. By 2006 the spread of broadband has lowered the real price to $17. That subscriber now enjoys consumer surplus of $3 per year, even as the lower price lures more subscribers. The authors reckon that by 2006 broadband was generating $39 billion in revenue and $5 billion-$7 billion in consumer surplus a year. Based on its share of online viewing, Mr Greenstein thinks Wikipedia accounted for up to $50m of that surplus.
Such numbers probably understate things. The authors’ calculations assume internet access meant the same thing in 2006 as it did in 1999. But the advent of new services such as Google and Facebook meant internet access in 2006 was worth much more than in 1999. So the surplus would have been bigger, too.
More important, consumers may not incorporate the value of free internet services when deciding what to pay for internet access. Another approach is simply to ask consumers what they would pay if they had to. In a study commissioned by IAB Europe, a web-advertising industry group, McKinsey, a consultancy, asked 3,360 consumers in six countries what they would pay for 16 internet services that are now largely financed by ads. On average, households would pay €38 ($50) a month each for services they now get free. After subtracting the costs associated with intrusive ads and forgone privacy, McKinsey reckoned free ad-supported internet services generated €32 billion of consumer surplus in America and €69 billion in Europe. E-mail accounted for 16% of the total surplus across America and Europe, search 15% and social networks 11%.
Another way to infer consumer surplus is from the time saved using the internet. In a paper partly funded by Google, Yan Chen, Grace YoungJoo Jeon and Yong-Mi Kim, all of the University of Michigan, asked a team of researchers to answer questions culled from web searches. The questions included teasers like: “In making cookies, does the use of butter or margarine affect the size of the cookie?” On average, it took participants seven minutes to answer the questions using a search engine, and 22 minutes using the University of Michigan’s library. Hal Varian, Google’s chief economist, then calculated that those savings worked out to 3.75 minutes per day for the typical user. Assigning that time a value of $22 per hour (the average wage in America), he reckons search generates $500 of consumer surplus per user annually, or $65 billion-$150 billion nationally.
Twitter: the defence
Yet another technique is to assign a value to the leisure time spent on the web. Erik Brynjolfsson and Joo Hee Oh of the Massachusetts Institute of Technology note that between 2002 and 2011, the amount of leisure time Americans spent on the internet rose from 3 to 5.8 hours per week. The authors conclude that in so far as consumers must have valued their time on the internet more than the alternatives, this increase must reflect a growing consumer surplus from the internet, which they value at $564 billion in 2011, or $2,600 per user. Had this growth in surplus been included in GDP, it would have raised economic growth since 2002 by 0.39 percentage points on average.
These are impressive figures, but they also merit scepticism. Would consumers really pay $2,600 for the internet? Shouldn’t other free leisure activities, such as watching television or—heaven forbid—playing with your children, have just as much value? And in other ways the internet subtracts value: the productivity destroyed by incessant checking of Twitter, the human interactions replaced by e-mail. Ms Mollica says people in hospital waiting rooms used to develop a camaraderie rooted in their shared experiences. “But now everyone stares into their phone because they’re texting or e-mailing.”
Fonte: aqui
Shane Greenstein of Northwestern University and Ryan McDevitt of the University of Rochester calculated the consumer surplus generated by the spread of broadband access (which ought to include the surplus generated by internet services, since that is why consumers pay for broadband). They did so by constructing a demand curve. Say that in 1999 a person pays $20 a month for internet access. By 2006 the spread of broadband has lowered the real price to $17. That subscriber now enjoys consumer surplus of $3 per year, even as the lower price lures more subscribers. The authors reckon that by 2006 broadband was generating $39 billion in revenue and $5 billion-$7 billion in consumer surplus a year. Based on its share of online viewing, Mr Greenstein thinks Wikipedia accounted for up to $50m of that surplus.
Such numbers probably understate things. The authors’ calculations assume internet access meant the same thing in 2006 as it did in 1999. But the advent of new services such as Google and Facebook meant internet access in 2006 was worth much more than in 1999. So the surplus would have been bigger, too.
More important, consumers may not incorporate the value of free internet services when deciding what to pay for internet access. Another approach is simply to ask consumers what they would pay if they had to. In a study commissioned by IAB Europe, a web-advertising industry group, McKinsey, a consultancy, asked 3,360 consumers in six countries what they would pay for 16 internet services that are now largely financed by ads. On average, households would pay €38 ($50) a month each for services they now get free. After subtracting the costs associated with intrusive ads and forgone privacy, McKinsey reckoned free ad-supported internet services generated €32 billion of consumer surplus in America and €69 billion in Europe. E-mail accounted for 16% of the total surplus across America and Europe, search 15% and social networks 11%.
Another way to infer consumer surplus is from the time saved using the internet. In a paper partly funded by Google, Yan Chen, Grace YoungJoo Jeon and Yong-Mi Kim, all of the University of Michigan, asked a team of researchers to answer questions culled from web searches. The questions included teasers like: “In making cookies, does the use of butter or margarine affect the size of the cookie?” On average, it took participants seven minutes to answer the questions using a search engine, and 22 minutes using the University of Michigan’s library. Hal Varian, Google’s chief economist, then calculated that those savings worked out to 3.75 minutes per day for the typical user. Assigning that time a value of $22 per hour (the average wage in America), he reckons search generates $500 of consumer surplus per user annually, or $65 billion-$150 billion nationally.
Twitter: the defence
Yet another technique is to assign a value to the leisure time spent on the web. Erik Brynjolfsson and Joo Hee Oh of the Massachusetts Institute of Technology note that between 2002 and 2011, the amount of leisure time Americans spent on the internet rose from 3 to 5.8 hours per week. The authors conclude that in so far as consumers must have valued their time on the internet more than the alternatives, this increase must reflect a growing consumer surplus from the internet, which they value at $564 billion in 2011, or $2,600 per user. Had this growth in surplus been included in GDP, it would have raised economic growth since 2002 by 0.39 percentage points on average.
These are impressive figures, but they also merit scepticism. Would consumers really pay $2,600 for the internet? Shouldn’t other free leisure activities, such as watching television or—heaven forbid—playing with your children, have just as much value? And in other ways the internet subtracts value: the productivity destroyed by incessant checking of Twitter, the human interactions replaced by e-mail. Ms Mollica says people in hospital waiting rooms used to develop a camaraderie rooted in their shared experiences. “But now everyone stares into their phone because they’re texting or e-mailing.”
Fonte: aqui
11 março 2013
22 fevereiro 2013
A ciência do vício em pornografia
A dopamina é liberada como um prêmio quando conquistamos algo. Seja comer, por exemplo, para a manutenção da vida, ou praticar atividades sexuais, para gerar vidas futuras. Essa dopamina consolida conexões neurais com o propósito de repetirmos aquela mesma atividade futuramente. Sabe-se que a dopamina é liberada durante a excitação sexual e o vídeo trata sobre o vício em pornografia, a “droga de escolha” via internet:
17 janeiro 2013
10 janeiro 2013
29 dezembro 2012
A magia da leitura
Todos nós, jovens e menos jovens, estamos crescentemente dependentes da plataforma virtual. É fascinante o apelo da web. Investimos muito tempo digitando mensagens de texto, escrevendo nos blogs, postando fotos e comentários no Facebook ou curtindo videogames. Eu mesmo já fiz o propósito de não acessar meus e-mails nos fins de semana. Tem sido uma luta. Com vitórias, mas também com derrotas. Para o norte-americano Nicholas Carr, formado em Harvard e autor de livros de tecnologia e administração, a dependência da troca de informações pela internet está empobrecendo a nossa cultura. Ele não fala do uso da internet, mas da compulsão virtual.
Segundo Carr, o uso exagerado da internet está reduzindo nossa capacidade de pensar com profundidade. "Você fica pulando de um site para o outro. Recebe várias mensagens ao mesmo tempo. É chamado pelo Twitter, pelo Facebook ou pelo Messenger. Isso desenvolve um novo tipo de intelecto, mais adaptado a lidar com as múltiplas funções simultâneas, mas que está perdendo a capacidade de se concentrar, ler atentamente ou pensar com profundidade", acentua.
A nova geração de adolescentes tem mais acesso à informação do que qualquer outra antes dela. Mas isso não se reflete num ganho cultural. Os índices de leitura e de compreensão de texto vêm caindo desde o início dos anos 1990. A conclusão é que, apesar do maior acesso às novas tecnologias, não se vê um ganho expressivo em termos de apreensão de conhecimento.
A internet é uma formidável ferramenta. Não deve, contudo, perder o seu caráter instrumental. O excesso de internet termina em compulsão, um tipo de dependência que já começa a preocupar os especialistas em saúde mental. Usemos a internet, mas tenhamos moderação. Precisamos, todos, redescobrir a magia da leitura.
[...]
12 dezembro 2012
23 outubro 2012
Internet, Privacidade e Política
Um interessante artigo do ProPublica (How Companies Have Assembled Political Profiles for Millions of Internet Users, Lois Beckett) destaca que alguns cookies, instalados nos nossos computadores, estão dando informação sobre as nossas preferências políticas. Estas informações, em conjunto com estimativa de salário, onde você mora, entre outras, estão alimentando empresas, como a CampaignGrid. Esta empresa, por sinal, montou uma apresentação onde informa que os usuários da internet não são anônimos (foto ao lado).
O ProPublica identificou sete empresas capazes de rastrear as preferências políticas dos usuários. Algumas destas empresas estão trabalhando em conjunto com companhias maiores tais como Facebook, Yahoo ou Microsoft. As informações coletadas abrangeriam 80% dos eleitores dos Estados Unidos.
10 outubro 2012
O que o seu "rastro" diz sobre você?
Um vídeo que me surpreendeu pelas pessoas realmente acreditarem e se assustarem com o médium. Saber o número da sua conta é um tanto exagerado né?
Com as faturas de cartão de crédito (que talvez você jogue fora sem rasgar) é possível saber seu estilo de vida: se você mora sozinho ou tem filhos, tem carro, viaja (fica em hotel cinco estrelas?), compra muitas roupas ou vai a bares e boates. Com as redes sociais ficou ainda mais fácil traçar o seu perfil – o que você compartilha? Quais fan pages (ou contas no twitter, instagram, pinterest)“curte” ? Quantos “amigos” tem? Como é a sua interação nesse ambiente?
Isso pode ser usado para o seu “bem” – com base no seu perfil, são direcionados anúncios que possam te interessar, ou para o seu mal – um médium tirando o seu dinheiro ou a orientadora que te adiciona para saber se você está terminando o trabalho ou se está na festa é o mais simples. Tenho certeza que coisas mais elaboradas virão à sua mente...
Indicado por Ednilto Tavares Júnior, a quem agradecemos.
25 setembro 2012
Segurança bancária
O vídeo a seguir, de um banco belga, mostra a importância de tomar cuidado com os dados que você coloca na internet.
13 agosto 2012
29 julho 2012
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