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FRACT | An Indie Adventure Game by Phosfiend Systems The world can be powered by alternative energy, using today's technology, in 20-40 years, says Stanford researcher Mark Z. Jacobson | Stanford News Release January 26, 2011 A new study – co-authored by Stanford researcher Mark Z. Jacobson and UC-Davis researcher Mark A. By Louis Bergeron If someone told you there was a way you could save 2.5 million to 3 million lives a year and simultaneously halt global warming, reduce air and water pollution and develop secure, reliable energy sources – nearly all with existing technology and at costs comparable with what we spend on energy today – why wouldn't you do it? According to a new study coauthored by Stanford researcher Mark Z. "Based on our findings, there are no technological or economic barriers to converting the entire world to clean, renewable energy sources," said Jacobson, a professor of civil and environmental engineering. He and Mark Delucchi, of the University of California-Davis, have written a two-part paper in Energy Policy in which they assess the costs, technology and material requirements of converting the planet, using a plan they developed.

proyeccion de 3d a 2d - Matemáticas Son matrices, lo que ocurre es que el programa de Todoexpertos elimina los espacios. De todas formas es equivalente lo siguiente: x' = x*cos(a) -y*sen(a) y' = x*sen(a) +y*cos(a) z' = z donde a es el ángulo que rota el eje OZ. x' = x*cos(b) -z*sen(b) y' = y z' = x*sen(b) + z*cos(b) y b es lo que has rotado el eje OY hasta ese momento. x' = x y' = y*cos(c) -z*sen(c) z' = y*sen(c) + z*cos(c) Rotas primero sobre OZ (con la variable a, que es el ángulo este), y obtienes x1, y1, z1, y estos los pones en las segundas fórmulas a la derecha y obtienes x2, y2, y3, y estos los pones en las terceras fórmulas a la derecha, y obtienes x3, y3, z3, que serán las coordenadas del punto una vez rotados los tres ejes. Con respecto a esto último, hay unas fórmulas en el web que pone lo siguiente (parece que se trata de un programador de gráficos): m_ancho = ancho_pantalla / 2; m_alto = alto_pantalla / 2; x_pantalla = (+(x_3D / z_3D) + m_ancho) * m_ancho; y_pantalla = (-(y_3D / z_3D) + m_alto) * m_alto;

Metcalfe's law Two telephones can make only one connection, five can make 10 connections, and twelve can make 66 connections. Metcalfe's law states that the value of a telecommunications network is proportional to the square of the number of connected users of the system (n2). First formulated in this form by George Gilder in 1993,[1] and attributed to Robert Metcalfe in regard to Ethernet, Metcalfe's law was originally presented, circa 1980, not in terms of users, but rather of "compatible communicating devices" (for example, fax machines, telephones, etc.)[2] Only more recently with the launch of the Internet did this law carry over to users and networks as its original intent was to describe Ethernet purchases and connections.[3] The law is also very much related to economics and business management, especially with competitive companies looking to merge with one another. Network effects[edit] Limitations[edit] Business practicalities[edit] Modified models[edit] See also[edit] References[edit]

How to Learn a Programming Language: 7 steps Edit Article Edited by Bourkas, Tom Viren, Ben Rubenstein, Compmod129 and 77 others Whether you want to design a video game, develop some cool apps for iPhone or Android or just want to do it for fun, programming is the way to go. There are countless programming languages for all sorts of uses, but learning them is easy once you learn how to use one. As a beginner, you'll probably start with Java or HTML. Ad Steps 1Decide your goal. 10Have a lot of practice. Tips When you learn something new, it is often helpful to implement it yourself and then tweak the design, predicting the results, to make sure you understand the concept.For practice, try to teach others. Sources and Citations How To Become A Hacker, an essay by Eric S.

7 easy Screen-Sharing and Remote-Access Tools (All Free) Advertisement Do you want to share your Windows screen with a friend or colleague so they can troubleshoot technical issues? Perhaps you want to access your Windows desktop from your tablet to watch a movie in bed? It’s easier than ever to get remote access to your machine, with many free tools available. Stay on Your Couch! 3 Free Apps to Remote Control Your Windows PC Stay on Your Couch! Let me introduce you to seven of the best. 1. TeamViewer is perhaps the most well-known of all the third-party tools available. It doesn’t just specialize in screen-sharing and remote-access. By default, you need to enter a PIN code to connect to someone else’s machine. Unlike some of its competitors, the software also allows group sessions. Best for: All-around screen-sharing and remote-access. 2. Chrome Remote Desktop has one glaring drawback – both computers need to have the Chrome browser installed. Best for: Quickly troubleshooting Granny’s laptop. 3. Best for: Using in a small office environment.

What Loyalty? High-End Customers are First to Flee Businesses that offer their customers the highest levels of service might like to believe that all their efforts to pamper and please will pay off with an extremely loyal following. “Customers you might expect to be the most ’stuck' are the ones who are disproportionately vulnerable to service competition.” But as new research from Harvard Business School demonstrates, the customers you think are your best and most loyal are likely to be the first to cast you aside when a challenger to your service superiority barges into the market. "Our results suggest that this is due to increasing expectations for service in these markets—the longer a firm has held a service advantage in a local market, the more sensitive are its customers to it service levels relative to those of competitors," says Harvard Business School's Dennis Campbell. In other words, you reap what you sow. In How Do Incumbents Fare in the Face of Increased Service Competition? Differences across markets Consider Sheraton Hotels.

Vitutor Why programmers work at night [This essay has been expanded into a book, you should read it, here] Image via Wikipedia A popular saying goes that Programmers are machines that turn caffeine into code. And sure enough, ask a random programmer when they do their best work and there’s a high chance they will admit to a lot of late nights. At the gist of all this is avoiding distractions. I think it boils down to three things: the maker’s schedule, the sleepy brain and bright computer screens. The maker’s schedule Paul Graham wrote about the maker’s schedule in 2009 – basically that there are two types of schedules in this world (primarily?). On the other hand you have something PG calls the maker’s schedule – a schedule for those of us who produce stuff. This is why programmers are so annoyed when you distract them. Because of this huge mental investment, we simply can’t start working until we can expect a couple of hours without being distracted. The sleepy brain But even programmers should be sleeping at night. Fin Fin

RechargeIT.org RechargeIT was launched in 2007 as an effort within Google.org to demonstrate plug-in electric vehicle (EV) technology and accelerate its adoption. With several new EV’s now available in the marketplace, we’ve retired the RechargeIT initiative. In fact, we’ve updated our EV infrastructure to include more than 30 of the newest plug-in vehicles as part of our employee car sharing service, Gfleet. We’ve started with the Chevrolet Volt and Nissan Leaf and we’ll be adding new models as they become available. When we launched RechargeIT in 2007, there were no commercially available plug-in hybrid EV’s available in the market. The RechargeIT Demonstration Fleet Back in 2007, with no commercially available vehicles to test, we had eight Toyota Prius’ retrofitted to make them plug-in hybrid vehicles. The system to collect data from our fleet consisted of an embedded computer running Linux, a wireless data card, a GPS and an AC power monitoring device to monitor charge power. See full results »

Sneaky VFX » Archive » Perverts September 7th, 2011 My niece had another birthday! I tried to share some more knowledge with her. Some have encouraged me to look for ways to get these published, which I will do as soon as I think of something to call them.

Des problèmes à résoudre utilisant les maths et la programmation : traduction voir site : by labo_m_toucy Apr 30

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