thegoodfellas/blogset-br huggingface dataset:
backpack is the public part, and the individual weights are the private part.This basic backpack enables us to share a secret without really sharing it. If we each have a backpack, then we can both share secrets.The backpack works well enough for smaller numbers, but it isnt useful in the real world. Backpack algorithms were a mere curiosity for decades. Then RSA changed everything.RSARSA was the first public-key encryption system that worked in the real world. Invented more than 30 years ago, it coincided with the introduction of the more powerful computers that were needed to run the big numbers. RSA is still the most popular public-key encryption system in the world.The basic premise of RSA is that factoring large numbers is difficult. Lets choose two prime numbers: 61 and 53. Im using the numbers from Wikipedias article on RSA in case you want more details.Multiply these two numbers and you get 3233:61 53 = 3233The security of RSA comes from the difficulty of getting back to 61 and 53 if you only know 3233. Theres no good way to get the factors of 3233 (i.e. the numbers that multiply to make the result) without just looking for all of them. To think of this another way, the weight of our backpack is 3233 kilos, and inside are 61 weights weighing 53 kilos each. If you make the resulting number large enough, then finding the numbers that produced it would be very difficult.Public And Private KeysUnlike the one-time pad, RSA uses the public key to encrypt information and the private key to decrypt it. This works because of the special relationship between the public and private keys when they were generated, which allows you to encrypt with one and decrypt with the other.You can share the public key with anyone and never reveal the private key. If you want to send me a secret message, just ask for my public key and use it to encrypt the message. You can then send it to anyone you want, and youll know that Im the only one who can decrypt the message and read it.I could send you a message in the same way. I would ask for your public key, encrypt the message using it and then send it to you to decrypt. The popular program Pretty Good Privacy (PGP) worked like that. Were secure as long as we both keep our private keys private.Exchanging keys is made even easier by special key servers that allow you to search for people and find their public keys.Public-key encryption also works in reverse to provide digital signatures. Lets say I want to write a message and prove that I wrote it. I just encrypt it with my private key and post it. Then anyone who wants to check can decrypt it with my public key. If the decryption works, then it means I have the private key and I wrote the message.RSA is relatively simple: take two numbers (the private key), apply some math, and get a third number (the public key). You can write
out all of the math in a few lines, and yet RSA changed the world. Business doesnt work on the Internet without public-key encryption.RSA And HTTPSWe use public-key encryption every day with HTTPS. When you access Facebook, Twitter or Amazon with HTTPS, youre using a simple encryption mechanism like the one-time pad, but youre creating the pad with public-key encryption. Without HTTPS, anyone else at Starbucks could read your credit-card number, Facebook password or private email while sipping a latte.Amazon has a certificate from a company named VeriSign. The certificate certifies that Amazon is Amazon, and it contains its public key. Your browser creates a special key just for that session and encrypts it using Amazons public key. Then it sends it over the Internet, knowing that only Amazon can decrypt the session key. Once youve exchanged that secret key, you can use it as the one-time pad to protect your password and credit-card number.You could keep using public-key encryption for the whole session, but because of all the math, its much slower than the one-time pad.RSA And GitHubAnother place many of us use RSA is GitHub. Every time you push a change to GitHub or pull from a master branch, GitHub has to make sure you have permission to make the change. It gets its security through a secure command shell using RSA.Remember when you set up your GitHub account and followed some commands to generate keys?You used the SSH-Keygen tool to generate a new RSA private/public key pair. Then you went to your GitHub account page and entered your public key.Now, when GitHub needs to authenticate you, it asks your computer to sign something with your private key and return the signed data. With your public key, GitHub can confirm that the signature is authentic and could only have been produced by someone who has the corresponding private keyeven though GitHub itself doesnt have that private key.Thats better than a simple password because nobody can snoop it. And if GitHub ever gets hacked, your private key wont be in danger because only you have it.Sharing PasswordsWhen WordPress.org was hacked, it wasnt really hacked. WordPress plugin developers, like everyone else, have accounts on other websites. They also reuse their passwords. When hackers cracked those other websites, they used the stolen passwords to log into WordPress.org and make malicious changes to plugins.Most people use the same user name and password on multiple websites. That makes your website only as secure as everyone elses. Public-key encryption changes that. Because you never have to share your private key, it doesnt matter if other websites get hacked. If an attacker breaks into GitHub and gets your public key, they cant use it to impersonate you or log in as you on other websites. Only someone with your private key can do that, which is why your private key remains safe on your computer. Using public-key cryptography makes GitHub much more secure.GitHub Gets HackedGitHub was hacked recently, but not because the encryption failed. Real-world security breaches are caused by problems in implementation, not in math.In this
case, the hacker was able to exploit a hole and add his public key to the Ruby on Rails repository. Once the key was added, GitHub used it to verify the hackers identity and granted him access. Were lucky this hacker was friendly and told GitHub about the issue.Once the problem was fixed, you could keep using your private key because GitHub never had it to lose; it stayed on your machine. Public keys saved GitHub from serious problems.The weakest link in GitHubs security was in the mechanism that allowed clever users to add public keys to other projects without being authorized. The math was perfect, but the implementation wasnt.Public Keys In The WildKnowing the fundamentals is essential (you might say the key) to writing secure applications. The math is complex, but the basics are simple:There are two main types of encryption: shared-key encryption, such as a one-time pad, and public-key encryption, which uses public and private keys.Shared-key encryption is faster, but sharing the keys is difficult.RSA is the most popular public-key encryption algorithm, but a few others are in general use, as well as some cool experimental systems.Public-key cryptography works best in combination with other technologies.Dont ever share your private key with anyone.When it comes time to implement public-key cryptography in your application, dont. RSA and other algorithms are already implemented in all major languages. These libraries include extra security features such as padding and salts, and they have a lot of testing behind them.Most security flaws come from poor implementations and misunderstanding about the libraries. You dont have to write your own cryptography libraries, but you do have to know the fundamentals so that you can use the ones that are out there.Illustrations in this article were provided by Robb Perry.(al) (km) Zack Grossbart for Smashing Magazine, 2012.
Summary for Week of May 11th: The key stories for the week were the elections in France and Greece, and JPMorgans $2 billion trading loss on a synthetic credit position. JPMorgan CEO Jamie Dimon said the losses were due to egregious mistakes, sloppiness" and that the "portfolio still has risk. This doesnt appear to be a systemic risk, just poor risk management at JPMorgan.The Greek political situation is unsettled, and the Europeans have said they support Greece through the next election on June 17th. After that ... who knows? There is a strong possibility that Greece will leave the euro not long after the next election.This was a light week for US economic data. The trade deficit was a little higher than expected, but most of the data improved slightly. The 4-week average of initial weekly unemployment claims declined, small business confidence improved, and consumer sentiment improved, and there were more job openings in March.In an under reported story, both Fannie and Freddie reported improved performance due to stabilization of house prices in certain areas. The sharp decline in "for sale" inventory appears to be supporting house prices, and inventory and house prices continue to be key stories for 2012.Here is a summary in graphs: Trade Deficit increased in March to $51.8 BillionThe trade deficit was above the consensus forecast of $49.5 billion.The first graph shows the monthly U.S. exports and imports in dollars through March 2012.Exports increased in March, and are at record levels. Imports increased even more. Exports are 13% above the pre-recession peak and up 7% compared to March 2011; imports are 3% above the pre-recession peak, and up about 8% compared to March 2011. The second graph shows the U.S. trade deficit, with and without petroleum, through March.The blue line is the total deficit, and the black line is the petroleum deficit, and the red line is the trade deficit ex-petroleum products.Oil averaged $107.95 per barrel in March, up from $103.63 in February. Import oil prices were probably a little higher in April too, but will probably decline in May. The increase in imports was a combination of more petroleum imports and more imports from China. BLS: Job Openings increased in MarchThis graph shows job openings (yellow line), hires (dark blue), Layoff, Discharges and other (red column), and Quits (light blue column) from the JOLTS. Jobs openings increased in March to 3.737 million, up from 3.565 million in February. The number of job openings (yellow) has generally been trending up, and openings are up about 17% year-over-year compared to March 2011. This is the highest level for job openings since July 2008.Quits increased in March, and quits are now up about 8.5% year-over-year and quits are now at the highest level since 2008. These are voluntary separations and more quits might indicate some improvement in the labor market. (see light blue columns at bottom of graph for trend for "quits").All current employment graphs REO Inventory for Fannie, Freddie and the FHAThis graph shows the combined REO inventory for Fannie, Freddie and the FHA (FHA through Feb 2012).The combined
REO inventory is down to 203 thousand in Q1 2012, down about 18% from Q1 2011.The pace of REO acquisitions will probably increase following the mortgage servicer settlement (signed off on April 5th); and dispositions will probably increase too. CoreLogic: House Price Index increases in March, Down 0.6% Year-over-yearFrom CoreLogic: CoreLogic March Home Price Index Shows Slight Year-Over-Year Decrease of Less Than One Percent[CoreLogic March Home Price Index (HPI) report] shows that nationally home prices, including distressed sales, declined on a year-over-year basis by 0.6 percent in March 2012 compared to March 2011. On a month-over-month basis, home prices, including distressed sales, increased by 0.6 percent in March 2012 compared to February 2012, the first month-over-month increase since July 2011. This graph shows the national CoreLogic HPI data since 1976. January 2000 = 100.The index was up 0.6% in March, and is down 0.6% over the last year. The index is off 34% from the peak - and is just above the post-bubble low set last month. Weekly Initial Unemployment Claims at 367,000Here is a long term graph of weekly claims:The dashed line on the graph is the current 4-week average. The four-week average of weekly unemployment claims decreased to 379,000.This decline in the 4-week moving average followed for four consecutive increases.This was close to the consensus of 366,000. This is two consecutive weeks with initial unemployment claims in the 360s, after averaging close to 390,000 over the previous 3 weeks.All current Employment Graphs NFIB: Small Business Optimism Index increases in AprilThis graph shows the small business optimism index since 1986. The index increased to 94.5 in April from 92.5 in March. This ties February 2011 as the highest level since December 2007.Another positive sign is that the "single most important problem" was not "poor sales" in April - for the first time in years. In the best of times, small business owners complain about taxes and regulations, and that is starting to happen again.This index remains low, but as housing continues to recover, I expect this index to increase (there is a high concentration of real estate related companies in this index). Consumer Sentiment increases in May to 77.8The preliminary Reuters / University of Michigan consumer sentiment index for May increased to 77.8, up from the April reading of 76.4.This was above the consensus forecast of 76.2 and the highest level since January 2008. Overall sentiment is still fairly weak - probably due to a combination of the high unemployment rate, high gasoline prices and the sluggish economy. Other Economic Stories ... LPS: House Price Index increased 0.2% in February Lawler: Table of Short Sales and Foreclosures for Selected Cities Sacramento: Percentage of Distressed House Sales increases slightly in April Lawler: REO inventory of "the F's" and PLS Fannie Mae reports $2.7 billion in income, REO inventory declines in Q1 2012 The economic impact of stabilizing house prices? The Declining Participation Rate Housing: Inventory declines 21% year-over-year in early May
Seven in 10 take notes on keyboards instead of paper, virtually all students who own an ereader and most use digital tools when preparing a presentation. All that tech has caused something of a dependency too 38% of students cant go more than 10 minutes without checking their smartphone or other device. All told, students spent $13 billion on electronics in 2009. Community college students are less digitally connected than students at four-year schools, but more and more people are making the Internet their education gateway. Twelve million students take at least one class online today in five years, that number is projected to exceed 22 million. By 2014, analysts say, more than 3.5 million students will take all of their classes online. This is all according to research compiled by Presta Electronics. Presta used material from the Pew Research Center, Chronicle of Higher Education, Mashable and other sources to put together the infographic below. Check it out for the full picture of how technology is changing college students lives. Do you think technology is changing college for the better or are there downsides? More About: education, infographics, Social Media, TechFor more Tech coverage:Follow Mashable Tech on TwitterBecome a Fan on FacebookSubscribe to the Tech channelDownload our free apps for Android, Mac, iPhone and iPad
proveta para doar um rim a irma doente - quer decidir sozinha o que fazer com o proprio corpo, nem que tenha que lutar por isso na justica.Voce acompanha mais o drama da familia do que o processo judicial.E em lagrimas o tempo todo.Carl Fredricksen, 78 anos e Russell, 8 sao a nova dupla e os mais novos EXCELENTES personagens criados pela Pixar no novo filme, Up: Altas Aventuras. O primeiro e um amargurado vendedor de baloes aposentado e viuvo(tristemente viuvo). O outro, um alegre e esforcado escoteiro,com problemas de atencao. Na aventura, ambos voam inadvertidamente juntos ao sul, em uma casa icada por milhares de baloes coloridos.A Pixar mais uma vez se superou.Alem de uma trama engracada,envolvente,voce tem otimos personagens.Eu particularmente amo o passaro Kevin e o cachorro Doug.Eu chorei em algumas partes.E recomendo!Apresentador de um programa de televisao chamado A Verdade Nua e Crua (The Ugly Truth), que da titulo ao filme, o sujeito explica, sem papas na lingua as vezes de forma bem grosseira, como funciona ambas as cabecas do homem.Mulherengo, ele dispara suas perolas de sabedoria machista para todos os lados. Sua nova produtora,vivida por Katherine Heigl, a romantica workaholic obcecada por controle Abby Ritcher precisa encontrar uma maneira de lidar com seu novo contratado se quiser continuar na emissora.E os dois,absolutamente diferentes,fazem no final o classico casal perfeito.O filme e engracado,mas eu achei muito cliche.Ja dava pra saber exatamente o que ia acontecer sem nem ter lido a sinopse.Mas da pra se divertir sim!
"Paulo Martinez, stylist mais que gabaritado, pontuou no ultimo Pense Moda que estao faltando revistas especializadas em moda no Brasil para que as pautas sobre o assunto sejam desenvolvidas com mais liberdade e menos quantidade de copias das "maes" internacionais (Vogue Brasil em relacao a Vogue America, Elle daqui em relacao a de la e assim sucessivamente).Mas, alem disso, outro fator limitador para o crescimento do mercado editorial fashion e o preco das revistas, que por ser alto nao atinge grande parte da populacao. Por isso, quando a iniciativa de colocar uma revista de moda inteirinha na internet e tomada, a gente tem mais e que divulgar aos quatro cantos.E a Melissa, dando inicio as comemoracoes dos 30 anos da marca, disponibilizou sua Plastic Dreams totalmente em PDF, pra ser baixada pela net da primeira a ultima pagina! Nao e incrivel?"Fonte: The Black Cat Walk Okay, o Ultrasuede ficou estacionado por muito tempo.Chegou a hora de limpar um pouco a poeira e fazer uma reforma. Que tal abranger as areas de debate e adicionar duas novas escritoras? Aguardem! Vou recomecar falando de Tattoo.E uma arte que eu e a Ju apreciamos muito. O que e Tatuagem A tatuagem ou Tattoo, na forma em ingles ou ate dermopigmentacao ("dermo" = pele / "pigmentacao" ato de pigmentar, ou colorir) e uma das formas de modificacao do corpo mais conhecidas e cultuadas do mundo. Nao significa porem que e respeitada - a maior parte da populacao ainda ve a tatuagem como sinal de rebeldia. Trata-se de um desenho permanente feito na pele que, tecnicamente, e uma aplicacao subcutanea obtida atraves da introducao de pigmentos por agulhas, um procedimento que durante muitos seculos foi completamente irreversivel (embora dependendo do caso, mesmo as tecnicas de remocao atuais possam deixar cicatrizes e variacoes de cor sobre a pele). A motivacao para os cultuadores dessa arte e ser uma obra de arte viva, e temporal tanto quanto a vida. O pai da palavra "tattoo" que conhecemos atualmente foi o capitao James Cook (tambem descobridor do surf), que escreveu em seu diario a palavra "tattow", tambem conhecida como "tatau"(era o som feito durante a execucao da tatuagem,em que se utilizavam ossos finos como agulhas e uma especie de martelinho para introduzir a tinta na pele).Com a circulacao dos marinheiros ingleses a tatuagem e a palavra Tatoo entraram em contato com diversas outras civilizacoes pelo mundo novamente.Porem o Governo da Inglaterra adotou a tatuagem como uma forma de identificacao de criminosos em 1879, a partir dai a tatuagem ganhou uma conotacao fora-da-lei no Ocidente. No Brasil, a tatuagem eletrica e uma arte muito recente, surgiu em meados dos anos 60 na cidade portuaria de Santos e foi introduzida pelo dinamarques "Knud Harld Likke Gregersen" tambem conhecido como Lucky Tattoo, que teve sua loja nas proximidades do cais, onde na epoca era a zona de boemia e prostituicao da cidade de Santos. Isto contribuiu bastante para a disseminacao de preconceitos e discriminacao da atividade. A localizacao da loja era zona de intensa circulacao de imigrantes embarcados, muitas vezes bebados, arruaceiros e envolvidos
cirurgia e as mulheres que ja deram a luz, sao normalmente quem diz que nao doi nada! Por outro lado, a maioria das pessoas sente algum incomodo nos primeiros minutos, mas depressa se habituam e chegam a conclusao que nao e tao mau como pensavam! Consequentemente, a dor e substituida pelas endorfinas, ate porque a partir de agora o pensamento esta apenas concentrado em ver o resultado final!Os grandes medos O medo da dor que uma tatuagem supostamente vai infligir esta por vezes relacionado com outros receios: o medo de agulhas e/ou de sangue! O primeiro e facilmente resolvido basta efectuar a tatuagem num local onde nao esta a assistir ao processo ou entao nao olhar; quanto ao segundo, e muito raro alguem sangrar ao ser tatuado, a nao ser que tenha bebido alcool ou tomado aspirina (ou outro medicamento que possa contribuir para a diluicao do sangue) imediatamente antes. Para alem disso, as agulhas apenas penetram cerca de 2.5 cm da pele pegue numa regua e veja com os seus proprios olhos e ao longo de toda a sessao, o tatuador limpa, vezes sem conta, a area de trabalho.Onde doi mais e menos? Para ficar com uma ideia da sensibilidade das diferentes zonas do seu corpo que pode estar a contemplar tatuar, faca esta experiencia: belisque a zona superior do braco e depois a parte de cima do pe. Doi mais no pe, nao e verdade? Regra geral, as zonas com mais musculo e/ou gordura doem bastante menos do que aquelas partes do corpo com uma alta concentracao de nervos, com ossos apenas e ainda algumas zonas erogenas.Mais probabilidade de dor: Orgaos genitais ou proximo dos mesmos Interior das coxas Tornozelos Pes Maos Esterno (osso situado na parte anterior do torax) Costelas Peito (principalmente para os homens) Zona inferior das costas Espinha dorsal Cabeca Qualquer zona da cara Pescoco Por de tras das orelhas AxilasMenos probabilidade de dor: Omoplatas Bracos Barriga da perna Exterior das coxas BumbumPrevenir a dor Existem historias dramaticas que incluem choro e ate desmaios durante uma tatuagem mas estes sao, sem duvida, casos isolados. O que pode acontecer e que a pessoa esta tao ansiosa que os nervos apoderam-se de toda a situacao, tornando a experiencia insuportavel; ou entao nao se alimentou correctamente antes da sessao; ou por outro lado, esta a fazer uma tatuagem muito grande e o corpo esta a responder negativamente a varias horas passadas nas maos de um tatuador.Para prevenir contra uma sessao dolorosa e para esquecer, considere as seguintes sugestoes: Descubra tudo o que puder sobre tatuagem quanto mais bem informado estiver, mais preparado estara na hora da verdade. Peca referencias e nao descanse ate encontrar um tatuador com o qual se sinta realmente confortavel. Pode sempre escolher uma zona do corpo a partida menos dolorosa para efectuar uma primeira tatuagem, mas se o que realmente quer e tatuar o tornozelo, por exemplo, peca ao tatuador para fazer um ensaio previo com as agulhas (e sem a tinta!) para ter uma ideia do que vai sentir. Mentalize-se que a dor faz parte