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The Seven Stages of Expertise in Software Engineering. © Copyright 1998, Wayland Systems Inc.

The Seven Stages of Expertise in Software Engineering

All rights reserved. (In this article, an indefinite “he” means “he or she”.) For almost two decades we at Wayland Systems Inc. have toiled to transfer the latest developments in software engineering to practitioners at large and small companies around the world. However, until recently we didn’t do a very good job of quantifying the long-term field results of our efforts. So we decided to ask a question reminiscent of the rhetoric of Ed Koch (the former mayor of ): “How’re we doin’?” We surveyed some of our clients to whom we’d provided education and consulting over the years and discovered an interesting but very disturbing fact.

We turned to self-examination and reviewed our courses and consulting practices. External examination revealed several factors at work, many of which were to do with corporate management habits. The above factors were significant and worthy of articles in their own right. “Very universal,” I answered. “Yes,” I said. A. B. From Altair to iPad: 35 years of personal computer market share. Back in 2005, we charted 30 years of personal computer market share to show graphically how the industry had developed, who succeeded and when, and how some iconic names eventually faded away completely.

From Altair to iPad: 35 years of personal computer market share

With the rise of whole new classes of "personal computers"—tablets and smartphones—it's worth updating all the numbers once more. And when we do so, we see something surprising: the adoption rates for our beloved mobile devices absolutely blow away the last few decades of desktop computer growth. People are adopting new technology faster than ever before. Humans are naturally competitive creatures. Not only do we compete with each other for money and power, but we form strong allegiances to various tribes. Well—there's certainly plenty of cheerleading, but tracking the rise of fall of market share over time has more serious uses, too.

Certain lessons from the past can also be applied today, and may even foreshadow what the future holds. So what is market share? XSS (Cross Site Scripting) Cheat Sheet. Last revision (mm/dd/yy): 04/2/2015 This cheat sheet is for people who already understand the basics of XSS attacks but want a deep understanding of the nuances regarding filter evasion.

XSS (Cross Site Scripting) Cheat Sheet

Please note that most of these cross site scripting vectors have been tested in the browsers listed at the bottom of the scripts. XSS Locator Inject this string, and in most cases where a script is vulnerable with no special XSS vector requirements the word "XSS" will pop up. Use this URL encoding calculator to encode the entire string. Recommender systems. A Guide to Recommender Systems. We're running a special series on recommendation technologies and in this post we look at the different approaches - including a look at how Amazon and Google use recommendations.

A Guide to Recommender Systems

The Wikipedia entry defines "recommender systems" as "a specific type of information filtering (IF) technique that attempts to present information items (movies, music, books, news, images, web pages, etc.) that are likely of interest to the user. " That entry goes on to note that recommendations are generally based on an "information item (the content-based approach) or the user's social environment (the collaborative filtering approach). " We think there's also a personalization approach, which Google in particular is focused on. (λ) Sketch of The Analytical Engine. By L.

Sketch of The Analytical Engine

F. MENABREAof Turin, Officer of the Military Engineers from the Bibliothèque Universelle de Genève, October, 1842, No. 82 With notes upon the Memoir by the Translator ADA AUGUSTA, COUNTESS OF LOVELACE Those labours which belong to the various branches of the mathematical sciences, although on first consideration they seem to be the exclusive province of intellect, may, nevertheless, be divided into two distinct sections; one of which may be called the mechanical, because it is subjected to precise and invariable laws, that are capable of being expressed by means of the operations of matter; while the other, demanding the intervention of reasoning, belongs more specially to the domain of the understanding.

Struck with similar reflections, Mr.

Quantum computing

Teorema dell'impilamento. Da Wikipedia, l'enciclopedia libera.

Teorema dell'impilamento

In crittanalisi il teorema dell'impilamento (piling-up lemma) è un principio utilizzato nella crittanalisi lineare per costruire le approssimazioni lineari dei cifrari a blocchi. È stato introdotto da Mitsuru Matsui nel 1993 come uno strumento analitico della crittanalisi lineare. Teoria[modifica | modifica sorgente] Il teorema dell'impilamento permette al crittanalista di determinare la probabilità che la seguente equazione sia valida: dove le x indicano variabili binarie (vale a dire con valore 0 o 1). Poniamo P(A) come indice della "probabilità che A sia vera": se è uguale a 1, A è certo che si verifichi; se è uguale a 0, A non si può verificare.

Adesso consideriamo: A causa delle proprietà dell'operazione di XOR, questa equazione è equivalente a Adesso esprimiamo le probabilità p1 e p2 come ½ + ε1 e ½ + ε2, dove le ε indicano la quantità dello scostamento dalla probabilità rapportata a ½. AI.