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Ahmed  One

Cryptography - Wikipedia, the free encyclopedia - 0 views

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    I think this Concept is very important to know.
Islam TeCNo

What's in an HTTP request? - 0 views

shared by Islam TeCNo on 15 Jun 09 - Cached
Ahmed Mansour liked it
  • These headers tell us which web server you were trying to contact.  If that seems odd, bear in mind that many web sites can be "hosted" on a single server, so when the request is received it needs to know which web site you were attempting to access
    • Islam TeCNo
       
      el server momken yekon 3aleh aktar men site ....3ashan keda lama bab3t request ba2olo bardo ana 3ayez site eh !!
  • The request method is usually either "GET" or "POST".  Basically if you fill in and submit a form on a web page it might generate a POST request (or it might be "GET"), whereas if you just click on a link, or activate one of your browser's "bookmarks" or "favourites", then the request method will always be "GET". Therefore, if it's "POST", we can tell that a form was definitely submitted.  The contents of the form would appear here, and there would also be some "Content-" headers describing the data. Web browsers generate two kinds of "POST" data: either "multipart/form-data", which is used when uploading files to a web server, or the more common "application/x-www-form-urlencoded".
    • Islam TeCNo
       
      el 7eta deh mohema ....we fe anwa3 tania bardo 3'er el GET we el POST
  • The "referer" header tells us which document referred you to us - in essence, if you followed a link to get to this page, it is the URL of the page you came from to get here.
    • Islam TeCNo
       
      el Referer by2ol lel server el page eli enta gaii menha ....we a3taked deh el tare2a eli fe sites betsta5dmha 3ashan temna3 maslan en sora aw keda tetshaf ela men el site zat nafso
  • ...2 more annotations...
  • Connection control Connection:keep-alive Keep-Alive:300 These headers are used to fine-tune the network traffic between you and the web server.  They don't tell us much, except a little about the capabilities of your web browser.
    • Islam TeCNo
       
      kan nefsi yekon fe shar7 lel 7eta deh aktar !!
  • Authorisation Username:not present If you have "logged in" to a web site, your username appears here. Note that this only applies to web sites which use proper HTTP authentication - typically, a "login" window pops up and you get three chances to enter your username and password, otherwise you see a page which says "Authentication Required" or similar.  It doesn't apply to web sites where the "login" is a separate page. It's also possible to supply the username and password in the URL you tell your browser to visit - for example, http://user:password@www.example.com/.  In that case, the username would appear here too.
    • Ahmed Mansour
       
      msh fahem el goz2 dah 2wey !! .. 7d yewad7ely please ...
    • Islam TeCNo
       
      ya3ni ya mans a7yanan fe sites bykon feha UserName we password 3an tare2 el HTTP protocol .....ya3ni el mail maslan aw cisclub dol fehom username we password mesh 3an tare2 el HTTP protocol ....el HTTP protocl el username we el pass beto3o bytlbo menak 2abl ma td5ol 3ala el page asasn we bytl3lk keda pop up tekteb feha
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    really very important and useful article ... thanks tecno very match :P
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    Nice Article Tecno..Go On
Islam TeCNo

OpenGL - Wikipedia, the free encyclopedia - 0 views

shared by Islam TeCNo on 10 Jun 09 - Cached
  • OpenGL (Open Graphics Library) is a standard specification defining a cross-language, cross-platform API for writing applications that produce 2D and 3D computer graphics. The interface consists of over 250 different function calls which can be used to draw complex three-dimensional scenes from simple primitives. OpenGL was developed by Silicon Graphics Inc. (SGI) in 1992[1] and is widely used in CAD, virtual reality, scientific visualization, information visualization, and flight simulation. It is also used in video games, where it competes with Direct3D on Microsoft Windows platforms (see Direct3D vs. OpenGL). OpenGL is managed by the non-profit technology consortium, the Khronos Group.
    • Mohamed Abd El Monem
       
      just some info about OGL :)
    • Islam TeCNo
       
      fe so2al bytra7 nafso !! ...ezaii el developers by3mlo API byshta3'l ma3 ay lo3'a !! ...ya3ni men el python OpenGL men el C++ OpenGL men el C# OpenGL!!
  • Mark Segal and Kurt Akeley authored the original OpenGL specification
    • Islam TeCNo
       
      2 Names to remember :D
    • Islam TeCNo
       
      LOL @ Book Names
  • ...2 more annotations...
  • (which actually has a white cover)
    • Islam TeCNo
       
      Realy LOL :D :D
  • The OpenGL standard allows individual vendors to provide additional functionality through extensions as new technology is created. Extensions may introduce new functions and new constants, and may relax or remove restrictions on existing OpenGL functions. Each vendor has an alphabetic abbreviation that is used in naming their new functions and constants. For example, NVIDIA's abbreviation (NV) is used in defining their proprietary function glCombinerParameterfvNV() and their constant GL_NORMAL_MAP_NV.
Abdelrahman Ogail

Theory of mind - Wikipedia, the free encyclopedia - 0 views

  • Theory of mind is the ability to attribute mental states—beliefs, intents, desires, pretending, knowledge, etc.—to oneself and others and to understand that others have beliefs, desires and intentions that are different from one's own.[1]
  • One of the most important milestones in theory of mind development is gaining the ability to attribute false belief: that is, to recognize that others can have beliefs about the world that are wrong. To do this, it is suggested, one must understand how knowledge is formed, that people’s beliefs are based on their knowledge, that mental states can differ from reality, and that people’s behavior can be predicted by their mental states. Numerous versions of the false-belief task have been developed, based on the initial task done by Wimmer and Perner (1983).
  • In the most common version of the false-belief task (often called the ‘Sally-Anne’ task), children are told or shown a story involving two characters. For example, in one version, the child is shown two dolls, Sally and Anne, playing with a marble. The dolls put away the marble in a box, and then Sally leaves. Anne takes the marble out and plays with it again, and after she is done, puts it away in a different box. Sally returns and the child is then asked where Sally will look for the marble. The child passes the task if she answers that Sally will look in the first box where she put the marble; the child fails the task if she answers that Sally will look in the second box, where the child knows the marble is hidden, even though Sally cannot know, since she did not see it hidden there. In order to pass the task, the child must be able to understand that another’s mental representation of the situation is different from their own, and the child must be able to predict behavior based on that understanding. The results of research using false-belief tasks have been fairly consistent: most normally-developing children are unable to pass the tasks until around the age of three or four.
    • Abdelrahman Ogail
       
      Test your small brother this test if he/she under 3 years!
Abdelrahman Ogail

Common Mistakes in Online and Real-time Contests - 0 views

  • Dynamic programming problems are to be solved with tabular methods
    • Ahmed Mansour
       
      Dynamic programming, like the divide-and-conquer method, solves problems by combining the solutions to subproblems. ("Programming" in this context refers to a tabular method, not to writing computer code) y3ney 3bara 3n 2nene bn2sem el problem el kbirr le shwit probelsm so3'ira .. we ne solve el problems deh we ngma el yab2a dh 7l lel problem el kbira :D;d see introduction to algorithms book . chapter 15
  • breadth-first search
    • Ahmed Mansour
       
      In graph theory, breadth-first search (BFS) is a graph search algorithm that begins at the root node and explores all the neighboring nodes. Then for each of those nearest nodes, it explores their unexplored neighbor nodes, and so on, until it finds the goal. ya3ney be el 3arby keda lw ana 3ndy tree maslan we el tree dh bettkwen mn shwit levels 3ady gedan.. lama hagey 23mel search 3la node mo3ina fi el tree deh hamsk el tree mn el root bet3ha ely hwa level 0 we habda2 2mshy level by level y3ney hanzl 3la el level 1 we hakaz le 3'it mal2y el node bet3ty ,,,, see this ,, it's a tutorial show how BFS algorithm is work!! http://www.personal.kent.edu/~rmuhamma/Algorithms/MyAlgorithms/GraphAlgor/breadthSearch.htm
  • Memorize the value of pi You should always try to remember the value of pi as far as possible, 3.1415926535897932384626433832795, certainly the part in italics. The judges may not give the value in the question, and if you use values like 22/7 or 3.1416 or 3.142857, then it is very likely that some of the critical judge inputs will cause you to get the wrong answer. You can also get the value of pi as a compiler-defined constant or from the following code: Pi=2*acos(0)
    • Islam TeCNo
       
      hhhhhhhhhhh ...... awl mara a3rf el mawdo3 dah we awl mara a3raf en el Pi = 2*acos(0)
    • Abdelrahman Ogail
       
      Thanks Islam for the info, really useful
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  • You cannot always check the equality of floating point numbers with the = = operator in C/C++. Logically their values may be same, but due to precision limit and rounding errors they may differ by some small amount and may be incorrectly deemed unequal by your program
  • #define swap(xxx, yyy) (xxx) ^= (yyy) ^= (xxx) ^= (yyy)
    • Islam TeCNo
       
      I remember someone told me that it's impossible to do swaping using macros :D ...but i think it's possible
  • But recursion should not be discounted completely, as some problems are very easy to solve recursively (DFS, backtracking)
    • Islam TeCNo
       
      Some problems are much easier when using recursion
  • Having a good understanding of probability is vital to being a good programmer
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    for bignner acmers hoping to be useful !
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    in this article the author discuss the common problems that faced teams in ACM contests .. and how to avoid it !
Abdelrahman Ogail

Artificial life - Wikipedia, the free encyclopedia - 2 views

  • Artificial life (commonly Alife or alife) is a field of study and an associated art form which examine systems related to life, its processes, and its evolution through simulations using computer models, robotics, and biochemistry.[1] There are three main kinds of alife[2], named for their approaches: soft[3], from software; hard[4], from hardware; and wet, from biochemistry. Artificial life imitates traditional biology by trying to recreate biological phenomena.[5] The term "artificial life" is often used to specifically refer to soft alife
  • The modeling philosophy of alife strongly differs from traditional modeling, by studying not only “life-as-we-know-it”, but also “life-as-it-might-be” [7].
Abdelrahman Ogail

ELIZA effect - Wikipedia, the free encyclopedia - 0 views

  • The effect is named for the 1966 chatterbot ELIZA, developed by MIT computer scientist Joseph Weizenbaum
    • Abdelrahman Ogail
       
      ELIZA was develped by a computer scientist from MIT!!
Ahmed Mansour

XHTML Frequently Answered Questions - 0 views

shared by Ahmed Mansour on 30 Jun 09 - Cached
Ahmed One liked it
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    i think this is great article to know the differences between html and xhtml ..!
Abdelrahman Ogail

Hill climbing - Wikipedia, the free encyclopedia - 0 views

  • In computer science, hill climbing is a mathematical optimization technique which belongs to the family of local search. It is relatively simple to implement, making it a popular first choice. Although more advanced algorithms may give better results, in some situations hill climbing works just as well. Hill climbing can be used to solve problems that have many solutions, some of which are better than others. It starts with a random (potentially poor) solution, and iteratively makes small changes to the solution, each time improving it a little. When the algorithm cannot see any improvement anymore, it terminates. Ideally, at that point the current solution is close to optimal, but it is not guaranteed that hill climbing will ever come close to the optimal solution. For example, hill climbing can be applied to the traveling salesman problem. It is easy to find a solution that visits all the cities but will be very poor compared to the optimal solution. The algorithm starts with such a solution and makes small improvements to it, such as switching the order in which two cities are visited. Eventually, a much better route is obtained. Hill climbing is used widely in artificial intelligence, for reaching a goal state from a starting node. Choice of next node and starting node can be varied to give a list of related algorithms.
Islam TeCNo

BBCode - Wikipedia, the free encyclopedia - 0 views

shared by Islam TeCNo on 26 Jun 09 - Cached
  • Bulletin Board Code or BBCode is a lightweight markup language used to format posts in many message boards. The available tags are usually indicated by square brackets surrounding a keyword, and they are parsed by the message board system before being translated into a markup language that web browsers understand—usually HTML or XHTML.
    • Islam TeCNo
       
      Simple :D
Islam TeCNo

specification - JSON-RPC - Trac - 0 views

  • 3. JSON Class hinting ¶ There are only simple data types defined in JSON. To overcome this problem in a JSON compatible way a special property for objects is introduced. {"__jsonclass__":["constructor", [param1,...]], "prop1": ...} The object is then instantiated using the constructor, passing in the parameters. Once constructed the properties (prop1, ...) will be applied.
    • Islam TeCNo
       
      JSON-RPC el mafroud feh data type wa7ed bas ....bas ana mesh fahem el 7eta deh awi !!
  • To give the serverside peer a chance to send messages to the client side peer, the client side peer may reopen communication by sending an empty HTTP POST.
    • Islam TeCNo
       
      mesh fahem el 7eta deh !! eh lazmet el empty post ya3ni !
  • --> {"method": "postMessage", "params": ["Hello all!"], "id": 99} <-- {"result": 1, "error": null, "id": 99} <-- {"method": "handleMessage", "params": ["user1", "we were just talking"], "id": null} <-- {"method": "handleMessage", "params": ["user3", "sorry, gotta go now, ttyl"], "id": null} --> {"method": "postMessage", "params": ["I have a question:"], "id": 101} <-- {"method": "userLeft", "params": ["user3"], "id": null} <-- {"result": 1, "error": null, "id": 101}
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    JSON-RPC is lightweight remote procedure call protocol similar to XML-RPC. It's designed to be simple!
Abdelrahman Ogail

Common Gateway Interface - Wikipedia, the free encyclopedia - 0 views

  • The Common Gateway Interface (CGI) is a standard protocol for interfacing external application software with an information server, commonly a web server. The task of such an information server is to respond to requests (in the case of web servers, requests from client web browsers) by returning output. Each time a request is received, the server analyzes what the request asks for, and returns the appropriate output. The two basic methods for the server to do this are the following: If the request identifies a file stored on disk, then return the contents of that file. If the request identifies an executable command and possibly arguments, then run the command and return its output. CGI defines a standard way of doing the second. It defines how information about the server and the request is passed to the command in the form of arguments and environment variables, and how the command can pass back extra information about the output (such as the type) in the form of headers.
Abdelrahman Ogail

Production system - Wikipedia, the free encyclopedia - 0 views

  • A production system (or production rule system) is a computer program typically used to provide some form of artificial intelligence, which consists primarily of a set of rules about behavior. These rules, termed productions, are a basic representation found useful in AI planning, expert systems and action selection. A production system provides the mechanism necessary to execute productions in order to achieve some goal for the system. Productions consist of two parts: a sensory precondition (or "IF" statement) and an action (or "THEN"). If a production's precondition matches the current state of the world, then the production is said to be triggered. If a production's action is executed, it is said to have fired. A production system also contains a database, sometimes called working memory, which maintains data about current state or knowledge, and a rule interpreter. The rule interpreter must provide a mechanism for prioritizing productions when more than one is triggered.
  • A production system (or production rule system) is a computer program typically used to provide some form of artificial intelligence, which consists primarily of a set of rules about behavior. These rules, termed productions, are a basic representation found useful in AI planning, expert systems and action selection. A production system provides the mechanism necessary to execute productions in order to achieve some goal for the system. Productions consist of two parts: a sensory precondition (or "IF" statement) and an action (or "THEN"). If a production's precondition matches the current state of the world, then the production is said to be triggered. If a production's action is executed, it is said to have fired. A production system also contains a database, sometimes called working memory, which maintains data about current state or knowledge, and a rule interpreter. The rule interpreter must provide a mechanism for prioritizing productions when more than one is triggered.
Islam TeCNo

Uniform Resource Identifier - Wikipedia, the free encyclopedia - 0 views

shared by Islam TeCNo on 16 Jun 09 - Cached
  • In computing, a Uniform Resource Identifier (URI) consists of a string of characters used to identify or name a resource on the Internet. Such identification enables interaction with representations of the resource over a network (typically the World Wide Web) using specific protocols. Schemes specifying a specific syntax and associated protocols define each URI. Contents [hide]
    • Abdelrahman Ogail
       
      I've confused between URL & URI till reading this article !
    • Islam TeCNo
       
      URL no3 men el URI :D ....ana faker eno kont shoft el 7eta deh fe ketab 3an el HTTP bas nesetha .......Zanks Zikas Again
  • A Uniform Resource Name (URN) functions like a person's name, while a Uniform Resource Locator (URL) resembles that person's street address. The URN defines an item's identity, while the URL provides a method for finding it. The ISBN system for uniquely identifying books provides a typical example of the use of typical URNs. ISBN 0486275574 (urn:isbn:0-486-27557-4) cites unambiguously a specific edition of Shakespeare's play Romeo and Juliet. In order to gain access to this object and read the book, one would need its location: a URL address. A typical URL for this book on a unix-like operating system might look like the file path file:///home/username/RomeoAndJuliet.pdf, identifying the electronic book saved in a local hard disk. So URNs and URLs have complementary purposes.
Islam TeCNo

Scalability - Wikipedia, the free encyclopedia - 0 views

  • In telecommunications and software engineering, scalability is a desirable property of a system, a network, or a process, which indicates its ability to either handle growing amounts of work in a graceful manner, or to be readily enlarged.[1] For example, it can refer to the capability of a system to increase total throughput under an increased load when resources (typically hardware) are added. An analogous meaning is implied when the word is used in a commercial context, where scalability of a company implies that the underlying business model offers the potential for economic growth within the company.
    • Abdelrahman Ogail
       
      In web applications, the client objects are removed from the server when they are sent to the client browser. This is great for scalability, but it can hurt the user and developer experience
    • Islam TeCNo
       
      mesh fahem ya Zikas commentak :D. we men el examples 3ala el scalabilty ...Gooogle we Gmail
    • Abdelrahman Ogail
       
      In Web applications client data are saved on the server (then the server memory is decreased that decreases the scalability - الإستيعاب-) So removing the client data improvers scalability becuase it saves server memory
    • Islam TeCNo
       
      ahaa :D Keshta.... ya3ni by3mlo delete 3ala el server ba3d lama el client ye3mel download :D hehe
Abdelrahman Ogail

Genetic algorithm - Wikipedia, the free encyclopedia - 0 views

  • A genetic algorithm (GA) is a search technique used in computing to find exact or approximate solutions to optimization and search problems. Genetic algorithms are categorized as global search heuristics. Genetic algorithms are a particular class of evolutionary algorithms (EA) that use techniques inspired by evolutionary biology such as inheritance, mutation, selection, and crossover (also called recombination).
  • A typical genetic algorithm requires: a genetic representation of the solution domain, a fitness function to evaluate the solution domain.
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    GE are primary used in Learning in AI
Islam TeCNo

Neuroplasticity - Wikipedia, the free encyclopedia - 0 views

  • Neuroplasticity (also referred to as brain plasticity, cortical plasticity or cortical re-mapping) is the changing of neurons and the organization of their networks and so their function by experience. This idea was first proposed in 1892 by Santiago Ramón y Cajal the proposer of the neuron doctrine though the idea was largely neglected for the next fifty years.[1] The first person to use the term neural plasticity appears to have been the Polish neuroscientist Jerzy Konorski.[2]
    • Abdelrahman Ogail
       
      This is why when a person thinks more he/she be more smarter!
    • Islam TeCNo
       
      3azeem .....bas deh mesh 7agat related l CS ya Zi3'az
    • Abdelrahman Ogail
       
      How said that? It's related to Artificial Neural Networks that require understanding of actual Human Neurons. BTW, plasticity principle is used in Games AI where the Controlled-AI determines if it forgot what happened or still remember it and seeks to revenge
    • Islam TeCNo
       
      oooooooooh ........ 3'reaaaaaat
Abdelrahman Ogail

SOAP - Wikipedia, the free encyclopedia - 0 views

  • SOAP, originally defined as Simple Object Access Protocol, is a protocol specification for exchanging structured information in the implementation of Web Services in computer networks. It relies on Extensible Markup Language (XML) as its message format, and usually relies on other Application Layer protocols (most notably Remote Procedure Call (RPC) and HTTP) for message negotiation and transmission. SOAP can form the foundation layer of a web services protocol stack, providing a basic messaging framework upon which web services can be built.
Islam TeCNo

Rich Internet application - Wikipedia, the free encyclopedia - 0 views

  • Rich Internet applications (RIAs) are web applications that have some of the characteristics of desktop applications, typically delivered by way of a proprietary web browser plug-ins or independently via sandboxes or virtual machines[1]. Examples of RIA frameworks include Curl (programming language), Adobe Flash/Adobe Flex/AIR, Java/JavaFX[2], uniPaaS[3] and Microsoft Silverlight[4].
    • Abdelrahman Ogail
       
      RIA Application Definition. Seems to be applications that could be used to Web and Desktop Development as Java
    • Islam TeCNo
       
      (Y) .....ana bardo kont 3ayez a3ref eh RIA deh :D
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    Very clear document :D .....need no explanation :D
Islam TeCNo

LOL - Wikipedia, the free encyclopedia - 0 views

shared by Islam TeCNo on 25 Jun 09 - Cached
  • OL (also written with some or all letters lowercase) is an abbreviation for laughing out loud[1][2] or laugh out loud.[3] LOL is a common element of Internet slang used historically on Usenet, but now widespread in other forms of computer-mediated communication, and even face-to-face communication. It is one of many initialisms for expressing bodily reactions, in particular laughter, as text, including initialisms such as ROTFL[4][5][6][7] or ROFL [8] ("roll(ing) on the floor laughing"), a more emphatic expression of laughter, and BWL ("bursting with laughter"), above which there is "no greater compliment" according to technology columnist Larry Magid.[9] Other unrelated expansions include the now mostly historical "lots of luck" or "lots of love" used in letter-writing.[10
    • Abdelrahman Ogail
       
      Source of the LOL
    • Islam TeCNo
       
      hehe LOL :D
  • Corruptions of "LOL"
    • Abdelrahman Ogail
       
      This is a big LOL
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