WolframAlpha : Une nouvelle sorte de science pour une nouvelle sorte de moteur de recherche Par Rémi Sussan le 03/06/09 | 6 commentaires | 6,463 lectures | Impression Aujourd’hui, vous avez sans doute déjà visité et utilisé WolframAlpha, et, selon vos préférences, vous l’avez trouvé plutôt extraordinaire, ou (surtout si vous êtes peu porté sur les chiffres), globalement décevant. Difficile pour l’instant de juger l’engin, qui n’en est, nous affirme-t-on, qu’à ses débuts (un truc à noter pour les collégiens et lycéens : il donne la solution des équations et trace les courbes de fonctions !). Car pour son créateur, le physicien Stephen Wolfram, également créateur du fameux logiciel Mathematica, pas de doute. Image : Stephen Wolfram, le créateur de Wolfram Alpha par Hybernaut. L’informatique est le socle de la structure du monde Qu’affirmait NKS (comme on a affectueusement surnommé ce livre) ? Autrement dit, le postulat en cours depuis Newton selon lequel les mathématiques étaient le langage de choix pour comprendre l’univers était une mauvaise habitude. Tout cela est bel et bon.
Presentación Consejos para Hablar en Público - Guía de Investigación para Estudiantes Public Speaking Tips Know the needs of your audience and match your contents to their needs. Know your material thoroughly. Put what you have to say in a logical sequence. When you are presenting in front of an audience, you are performing as an actor is on stage. Body language is important. Speak with conviction as if you really believe in what you are saying. Do not read from notes for any extended length of time although it is quite acceptable to glance at your notes infrequently. Maintain sincere eye contact with your audience. Speak to your audience, listen to their questions, respond to their reactions, adjust and adapt. Pause. Add humor whenever appropriate and possible. When using audio-visual aids to enhance your presentation, be sure all necessary equipment is set up and in good working order prior to the presentation. Have handouts ready and give them out at the appropriate time. Know when to STOP talking. Public Speaking Links: Advanced Public Speaking Institute.
L’avenir de la programmation : le langage naturel Il existe deux types de programmation du langage naturel ; celle qui est effectuée par les grosses compagnies comme IBM et Apple, sur laquelle on ne possède bien souvent que quelques indications, et celle élaborée par les milliers de créateurs, souvent amateurs, de « chatbots » (programmes conversationnels). Celle-ci peut susciter l’intérêt du non-programmeur désireux de s’initier à cette discipline, car les outils sont disponibles et les procédés bien balisés. Les connaissances structurées : une tâche complexe et couteuse en ressources Comment fonctionnent les « gros » programmes de reconnaissance du langage naturel ? En gros, on peut travailler selon deux stratégies distinctes. A première vue l’approche structurée semble plus sûre parce qu’elle évite par trop les ambiguïtés liées au langage et ne met pas trop de pression sur le programme informatique. Un gros programme de reconnaissance du langage comme Watson, l’ordinateur champion de Jeopardy, utilise en fait la première approche.
A Melting Arctic And Weird Weather: The Plot Thickens Everyone loves to talk about the weather, and this winter Mother Nature has served up a feast to chew on. Few parts of the US have been spared her wrath. Severe drought and abnormally warm conditions continue in the west, with the first-ever rain-free January in San Francisco; bitter cold hangs tough over the upper Midwest and Northeast; and New England is being buried by a seemingly endless string of snowy nor’easters. Yes, droughts, cold and snowstorms have happened before, but the persistence of this pattern over North America is starting to raise eyebrows. Is climate change at work here? Wavier jet stream One thing we do know is that the polar jet stream – a fast river of wind up where jets fly that circumnavigates the northern hemisphere – has been doing some odd things in recent years. Rather than circling in a relatively straight path, the jet stream has meandered more in north-south waves. Slowing, drunken path Jet streams exist because of differences in air temperature.
sans titre Ready to level up your working knowledge of math? Here’s what to read now — and next. Math 101, with Jennifer Ouellette First, start with these 5 books… 1. “First published in 1930, this classic text traces the evolution of the concept of a number in clear, accessible prose. 2. “This bestselling book originally published in 1988 remains one of the best introductions to the basics of large numbers, statistics and probabilities with illustrations drawn from everyday life: sports, the stock market, the lottery and dubious medical claims, to name a few.” 3. “Pair Paulos with the just-released How Not to Be Wrong. 4. “Most of us take zero for granted, but there was a time when it simply didn’t exist, until some enterprising Babylonian soul inserted it as a placeholder in Eastern counting methods. 5. “The prose gets a bit turgid at times, and some readers might be deterred by the proofs and equations scattered throughout, but Berlinski has some lovely descriptions and turns of phrases. 1. 2. 3.
How does the thyroid manage your metabolism? - Emma Bryce | TED-Ed For such a tiny organ that looks a lot like a butterfly, the thyroid gets a lot of attention. But it makes sense when you consider just how vital its task is: this gland helps to control the body's metabolism. If you're stuck trying to grasp why that's important and what exactly metabolism is, check out this helpful video, and read more about the thyroid's role here and here. The tools your thyroid uses to get the job done are triiodothyronine (T3) (that's a tricky word: learn how to say it!) and thyroxine (T4), the two hormones that act as messengers to all your body's cells. Fun fact: your thyroid needs an element called iodine to make these hormones, an ingredient your body can't make and which it has to get from the food you eat, instead. Since it works 24/7, it may seem like the thyroid is the boss in this situation. But when the all-powerful pituitary fails, your body really feels it, in the shape of hyperthyroidism and hypothyroidism.
Einstein Vs Quantum Mechanics ... And Why He’d Be A Convert Today Albert Einstein may be most famous for his mass-energy equivalence formula E = mc2, but his work also laid down the foundation for modern quantum mechanics. His analysis of the “spookiness” of quantum mechanics opened up a whole range of applications including quantum teleportation and quantum cryptography, but he wasn’t completely convinced by the theory of quantum mechanics – and that story is as fascinating as the theory he attempted to nail down. Quantum mechanics is downright bizarre. More famously, German physicist Erwin Schrödinger’s equations proved that a cat could end up in a peculiar sort of quantum state, being neither dead nor alive. None of this impressed Einstein. At the time, most quantum physicists adopted the “shut up and calculate” philosophy: get on with the job, and don’t worry about philosophical issues – just get the predictions. Gaining momentum (and position) If someone measures the position of a particle, the particle is disturbed, so its momentum changes.
Quantum mechanics 101: Demystifying tough physics in 4 easy lessons Ready to level up your working knowledge of quantum mechanics? Check out these four TED-Ed Lessons written by Chad Orzel, Associate Professor in the Department of Physics and Astronomy at Union College and author of How to Teach Quantum Physics to Your Dog. 1. Particles and waves: The central mystery of quantum mechanics One of the most amazing facts in physics is that everything in the universe, from light to electrons to atoms, behaves like both a particle and a wave at the same time. But how did physicists arrive at this mind-boggling conclusion? 2. Austrian physicist Erwin Schrödinger, one of the founders of quantum mechanics, posed this famous question: If you put a cat in a sealed box with a device that has a 50% chance of killing the cat in the next hour, what will be the state of the cat when that time is up? 3. When you think about Einstein and physics, E=mc^2 is probably the first thing that comes to mind. 4.