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Abdelrahman Ogail

Simulated annealing - Wikipedia, the free encyclopedia - 1 views

  • Simulated annealing (SA) is a generic probabilistic metaheuristic for the global optimization problem of applied mathematics, namely locating a good approximation to the global minimum of a given function in a large search space. It is often used when the search space is discrete (e.g., all tours that visit a given set of cities). For certain problems, simulated annealing may be more effective than exhaustive enumeration — provided that the goal is merely to find an acceptably good solution in a fixed amount of time, rather than the best possible solution. The name and inspiration come from annealing in metallurgy, a technique involving heating and controlled cooling of a material to increase the size of its crystals and reduce their defects. The heat causes the atoms to become unstuck from their initial positions (a local minimum of the internal energy) and wander randomly through states of higher energy; the slow cooling gives them more chances of finding configurations with lower internal energy than the initial one. By analogy with this physical process, each step of the SA algorithm replaces the current solution by a random "nearby" solution, chosen with a probability that depends on the difference between the corresponding function values and on a global parameter T (called the temperature), that is gradually decreased during the process. The dependency is such that the current solution changes almost randomly when T is large, but increasingly "downhill" as T goes to zero. The allowance for "uphill" moves saves the method from becoming stuck at local minima—which are the bane of greedier methods. The method was independently described by S. Kirkpatrick, C. D. Gelatt and M. P. Vecchi in 1983 [1], and by V. Černý in 1985 [2]. The method is an adaptation of the Metropolis-Hastings algorithm, a Monte Carlo method to generate sample states of a thermodynamic system, invented by N. Metropolis et al. in 1953 [3].
  • Simulated annealing (SA) is a generic probabilistic metaheuristic for the global optimization problem of applied mathematics, namely locating a good approximation to the global minimum of a given function in a large search space. It is often used when the search space is discrete (e.g., all tours that visit a given set of cities). For certain problems, simulated annealing may be more effective than exhaustive enumeration — provided that the goal is merely to find an acceptably good solution in a fixed amount of time, rather than the best possible solution. The name and inspiration come from annealing in metallurgy, a technique involving heating and controlled cooling of a material to increase the size of its crystals and reduce their defects. The heat causes the atoms to become unstuck from their initial positions (a local minimum of the internal energy) and wander randomly through states of higher energy; the slow cooling gives them more chances of finding configurations with lower internal energy than the initial one. By analogy with this physical process, each step of the SA algorithm replaces the current solution by a random "nearby" solution, chosen with a probability that depends on the difference between the corresponding function values and on a global parameter T (called the temperature), that is gradually decreased during the process. The dependency is such that the current solution changes almost randomly when T is large, but increasingly "downhill" as T goes to zero. The allowance for "uphill" moves saves the method from becoming stuck at local minima—which are the bane of greedier methods. The method was independently described by S. Kirkpatrick, C. D. Gelatt and M. P. Vecchi in 1983 [1], and by V. Černý in 1985 [2]. The method is an adaptation of the Metropolis-Hastings algorithm, a Monte Carlo method to generate sample states of a thermodynamic system, invented by N. Metropolis et al. in 1953 [3].
  • Simulated annealing (SA) is a generic probabilistic metaheuristic for the global optimization problem of applied mathematics, namely locating a good approximation to the global minimum of a given function in a large search space. It is often used when the search space is discrete (e.g., all tours that visit a given set of cities). For certain problems, simulated annealing may be more effective than exhaustive enumeration — provided that the goal is merely to find an acceptably good solution in a fixed amount of time, rather than the best possible solution. The name and inspiration come from annealing in metallurgy, a technique involving heating and controlled cooling of a material to increase the size of its crystals and reduce their defects. The heat causes the atoms to become unstuck from their initial positions (a local minimum of the internal energy) and wander randomly through states of higher energy; the slow cooling gives them more chances of finding configurations with lower internal energy than the initial one. By analogy with this physical process, each step of the SA algorithm replaces the current solution by a random "nearby" solution, chosen with a probability that depends on the difference between the corresponding function values and on a global parameter T (called the temperature), that is gradually decreased during the process. The dependency is such that the current solution changes almost randomly when T is large, but increasingly "downhill" as T goes to zero. The allowance for "uphill" moves saves the method from becoming stuck at local minima—which are the bane of greedier methods. The method was independently described by S. Kirkpatrick, C. D. Gelatt and M. P. Vecchi in 1983 [1], and by V. Černý in 1985 [2]. The method is an adaptation of the Metropolis-Hastings algorithm, a Monte Carlo method to generate sample states of a thermodynamic system, invented by N. Metropolis et al. in 1953 [3].
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  • Simulated annealing (SA) is a generic probabilistic metaheuristic for the global optimization problem of applied mathematics, namely locating a good approximation to the global minimum of a given function in a large search space. It is often used when the search space is discrete (e.g., all tours that visit a given set of cities). For certain problems, simulated annealing may be more effective than exhaustive enumeration — provided that the goal is merely to find an acceptably good solution in a fixed amount of time, rather than the best possible solution. The name and inspiration come from annealing in metallurgy, a technique involving heating and controlled cooling of a material to increase the size of its crystals and reduce their defects. The heat causes the atoms to become unstuck from their initial positions (a local minimum of the internal energy) and wander randomly through states of higher energy; the slow cooling gives them more chances of finding configurations with lower internal energy than the initial one. By analogy with this physical process, each step of the SA algorithm replaces the current solution by a random "nearby" solution, chosen with a probability that depends on the difference between the corresponding function values and on a global parameter T (called the temperature), that is gradually decreased during the process. The dependency is such that the current solution changes almost randomly when T is large, but increasingly "downhill" as T goes to zero. The allowance for "uphill" moves saves the method from becoming stuck at local minima—which are the bane of greedier methods. The method was independently described by S. Kirkpatrick, C. D. Gelatt and M. P. Vecchi in 1983 [1], and by V. Černý in 1985 [2]. The method is an adaptation of the Metropolis-Hastings algorithm, a Monte Carlo method to generate sample states of a thermodynamic system, invented by N. Metropolis et al. in 1953 [3].
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    Simulated annealing (SA) is a generic probabilistic metaheuristic for the global optimization problem of applied mathematics, namely locating a good approximation to the global minimum of a given function in a large search space. It is often used when the search space is discrete (e.g., all tours that visit a given set of cities). For certain problems, simulated annealing may be more effective than exhaustive enumeration - provided that the goal is merely to find an acceptably good solution in a fixed amount of time, rather than the best possible solution. The name and inspiration come from annealing in metallurgy, a technique involving heating and controlled cooling of a material to increase the size of its crystals and reduce their defects. The heat causes the atoms to become unstuck from their initial positions (a local minimum of the internal energy) and wander randomly through states of higher energy; the slow cooling gives them more chances of finding configurations with lower internal energy than the initial one. By analogy with this physical process, each step of the SA algorithm replaces the current solution by a random "nearby" solution, chosen with a probability that depends on the difference between the corresponding function values and on a global parameter T (called the temperature), that is gradually decreased during the process. The dependency is such that the current solution changes almost randomly when T is large, but increasingly "downhill" as T goes to zero. The allowance for "uphill" moves saves the method from becoming stuck at local minima-which are the bane of greedier methods. The method was independently described by S. Kirkpatrick, C. D. Gelatt and M. P. Vecchi in 1983 [1], and by V. Černý in 1985 [2]. The method is an adaptation of the Metropolis-Hastings algorithm, a Monte Carlo method to generate sample states of a thermodynamic system, invented by N. Metropolis et al. in 1953 [3].
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    A natural AI approach
magdy medhat

What is Domain Name Resolution - 0 views

  • What is Domain Name Resolution Introduction When using the Internet most people connect to web sites, ftp servers or other Internet servers by connecting to a domain name, as in www.bleepingcomputer.com. Internet applications, though, do not communicate via domain names, but rather using IP addresses, such as 192.168.1.1. Therefore when you type a domain name in your program that you wish to connect to, your application must first convert it to an IP address that it will use to connect to. The way these hostnames are resolved to their mapped IP address is called Domain Name Resolution. On almost all operating systems whether they be Apple, Linux, Unix, Netware, or Windows the majority of resolutions from domain names to IP addresses are done through a procedure called DNS.
    • Ahmed Mansour
       
      i think it's great artical !!
    • Islam TeCNo
       
      Yes .....we know that Web sites are on servers that has IP adresses like this 217.143.56.12 for example .....this article tell us how the site name [www.google.com] is converted to the IP thanks Mans
    • magdy medhat
       
      ya tecno ya gamedddddd mesh de elly kona bntklm feha fel microbus :D
  • Hosts File - There is a file called the HOSTS file that you can use to convert domain names to IP addresses. Entries in the HOSTS file override any mappings that would be resolved via a DNS server
    • Islam TeCNo
       
      I think this is what some spam and adware programs use .... you type a normal site Name but you go yo another site ... i think so !!
  • Netbios - This only applies to Windows machines and will only be used to map names to IP addresses if all previous methods failed. This method will attempt to map the netbios name you are trying to connect to with an IP address.
    • Islam TeCNo
       
      any body can explain this point for me ?
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  • This can be changed though by changing certain registry keys
    • Islam TeCNo
       
      start -> run -> regedit this will allow you to edit the registry
  • DnsPriority = 30 LocalPriority = 200 HostsPriority = 75 NetbtPriority = 100
    • Islam TeCNo
       
      Or Simpler DnsPriority = 1 HostsPriority = 2 NetbtPriority = 3 LocalPriority = 4
computersciencej

Difference Between File Transfer Protocol and Hyper Text Transfer Protocol - 0 views

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    In this post under Computer Science Study Material for Gate, we are going to tell the differences between File Transfer Protocol (FTP) and Hypertext Transfer Protocol (HTTP). File Transfer Protocol FTP and HTTP both were developed to make Internet transmission better. FTP is used to exchange files between computer accounts, to transfer files between an account and a desktop computer (upload), or to access software archives on the Internet. It 's also commonly used to download programs and other files to your computer from other servers. It transfers files in two different formats ASCII for text files and Binary format for binary files. To Read full Article click on folowing link http://www.computersciencejunction.in/2017/11/differences-between-ftp-and-http.html
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
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  • 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
Ahmed Mansour

CRC Cards Tutorial - 0 views

  • Object Oriented Analysis and Design using CRC Cards
  • A CRC cards is an index card that is use to represent the responsibilities of classes and the interaction between the classes. CRC cards are an informal approach to object oriented modeling. The cards are created through scenarios, based on the system requirements, that model the behavior of the system. The name CRC comes from Class, Responsibilities, and Collaborators which the creators found to be the essential dimensions of object oriented modeling.
    • Ahmed Mansour
       
      One of the most popular methods for identifying and categorizing classes is to use class-responsibility-collaboration cards (CRC). Each CRC card represents a single class's data attributes, responsibilities, and collaborations. source : Thought Process Book..
    • Ahmed Mansour
       
      You need to create three sections on each card: - The name of the class - The responsibilities of the class - The collaborations of the class
  • Why uses CRC cards?
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  • They are portable... No computers are required so they can be used anywhere. Even away from the office. The allow the participants to experience first hand how the system will work. No computer tool can replace the interaction that happens by physically picking up the cards and playing the roll of that object... The are a useful tool for teaching people the object-oriented paradigm. They can be used as a methodology them selves or as a front end to a more formal methodology such as Booch, Wirfs-Brock, Jacobson, etc.
  • Tutorial
    • Ahmed Mansour
       
      here we can found simple tutorial for illustration...
  • A CRC cards is an index card that is use to represent the responsibilities of classes and the interaction between the classes. CRC cards are an informal approach to object oriented modeling. The cards are created through scenarios, based on the system requirements, that model the behavior of the system. The name CRC comes from Class, Responsibilities, and Collaborators which the creators found to be the essential dimensions of object oriented modeling.
  • Why uses CRC cards? They are portable... No computers are required so they can be used anywhere. Even away from the office. The allow the participants to experience first hand how the system will work. No computer tool can replace the interaction that happens by physically picking up the cards and playing the roll of that object... The are a useful tool for teaching people the object-oriented paradigm. They can be used as a methodology them selves or as a front end to a more formal methodology such as Booch, Wirfs-Brock, Jacobson, etc.
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    This is great tutorial for CRC cards ( sort of object oriented modeling approach) \ni think it was useful for me ... hoping to be useful for all of us : ) ..
Janos Haits

https://nectome.com - 0 views

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    "Our mission is to preserve your brain well enough to keep all its memories intact: from that great chapter of your favorite book to the feeling of cold winter air, baking an apple pie, or having dinner with your friends and family. If memories can truly be preserved by a sufficiently good brain banking technique, we believe that within the century it could become feasible to digitize your preserved brain and use that information to recreate your mind. How close are we to this possibility? Currently, we can preserve the connectomes of animal brains and are working on extending our techniques to human brains in a research context. This is an important first step towards the development of a verified memory preservation protocol, as the connectome plays a vital role in memory storage."
computersciencej

TCP/IP model questions based Study Material for gate Computer Science - 0 views

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    TCP/IP protocol based questions for gate computer science exam Q1.What is the difference between transport and session layer of OSI model. Answer: OSI Model Transport Layer The transport layer uses the services provided by the network layer, such as best path selection and logical addressing, to provide end-to-end communication between source and destination. • The transport -layer data stream is a logical connection between the endpoints of a network. • End-to-end control is provided by sliding windows and reliability in sequencing numbers and acknowledgments. The transport layer regulates information flow to ensure end-to-end connectivity between host applications reliably and accurately. • The TCP/ IP protocol of Layer 4 (t transport t layer ) has two protocols. They are TCP and UDP. The transport layer accepts data from the session layer and segments the data for transport across the network. Generally, the transport layer is responsible for making sure that the data is delivered error-free and in the proper sequence. Flow control generally occurs at the transport layer. OSI Model Session Layer The session layer establishes, manages, and terminates communication sessions. Communication sessions consist of service requests and service responses that occur between applications located on different network devices. These requests and responses are coordinated by protocols implemented at the session layer. The session layer establishes, manages, and terminates sessions between applications Functions of the session layer and the different processes that occur as data packets travel through this layer. More specifically, you learned that Communication sessions consist of mini-conversations that occur between applications located on different network devices. Requests and responses are coordinated by protocols implemented at the session layer. • The session layer decides whether to use two-way simultaneous communication or two-way alternate communicati
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

Flocking (behavior) - Wikipedia, the free encyclopedia - 0 views

  • Flocking behavior is the behavior exhibited when a group of birds, called a flock, are foraging or in flight. There are parallels with the shoaling behavior of fish, or the swarming behavior of insects. Computer simulations and mathematical models which have been developed to emulate the flocking behaviors of birds can generally be applied also to the "flocking" behavior of other species. As a result, the term "flocking" is sometimes applied, in computer science, to species other than birds. This article is about the modelling of flocking behavior. From the perceptive of the mathematical modeller, "flocking" is the collective motion of a large number of self-propelled entities and is a collective animal behavior exhibited by many living beings such as birds, fish, bacteria, and insects.[1] It is considered an emergent behaviour arising from simple rules that are followed by individuals and does not involve any central coordination. Flocking behavior was first simulated on a computer in 1986 by Craig Reynolds with his simulation program, Boids. This program simulates simple agents (boids) that are allowed to move according to a set of basic rules. The result is akin to a flock of birds, a school of fish, or a swarm of insects.
  • Flocking behavior is the behavior exhibited when a group of birds, called a flock, are foraging or in flight. There are parallels with the shoaling behavior of fish, or the swarming behavior of insects. Computer simulations and mathematical models which have been developed to emulate the flocking behaviors of birds can generally be applied also to the "flocking" behavior of other species. As a result, the term "flocking" is sometimes applied, in computer science, to species other than birds. This article is about the modelling of flocking behavior. From the perceptive of the mathematical modeller, "flocking" is the collective motion of a large number of self-propelled entities and is a collective animal behavior exhibited by many living beings such as birds, fish, bacteria, and insects.[1] It is considered an emergent behaviour arising from simple rules that are followed by individuals and does not involve any central coordination. Flocking behavior was first simulated on a computer in 1986 by Craig Reynolds with his simulation program, Boids. This program simulates simple agents (boids) that are allowed to move according to a set of basic rules. The result is akin to a flock of birds, a school of fish, or a swarm of insects.
Abdelrahman Ogail

Clockwork universe theory - Wikipedia, the free encyclopedia - 1 views

  • The Clockwork Universe Theory is a theory, established by Isaac Newton, as to the origins of the universe. A "clockwork universe" can be thought of as being a clock wound up by God and ticking along, as a perfect machine, with its gears governed by the laws of physics. What sets this theory apart from others is the idea that God's only contribution to the universe was to set everything in motion, and from there the laws of science took hold and have governed every sequence of events since that time. This idea was very popular during the Enlightenment, when scientists realized that Newton's laws of motion, including the law of universal gravitation, could explain the behavior of the solar system. A notable exclusion from this theory though is free will, since all things have already been set in motion and are just parts of a predictable machine. Newton feared that this notion of "everything is predetermined" would lead to atheism. This theory was undermined by the second law of thermodynamics ( the total entropy of any isolated thermodynamic system tends to increase over time, approaching a maximum value) and quantum physics with its unpredictable random behavior.
  • The Clockwork Universe Theory is a theory, established by Isaac Newton, as to the origins of the universe. A "clockwork universe" can be thought of as being a clock wound up by God and ticking along, as a perfect machine, with its gears governed by the laws of physics. What sets this theory apart from others is the idea that God's only contribution to the universe was to set everything in motion, and from there the laws of science took hold and have governed every sequence of events since that time. This idea was very popular during the Enlightenment, when scientists realized that Newton's laws of motion, including the law of universal gravitation, could explain the behavior of the solar system. A notable exclusion from this theory though is free will, since all things have already been set in motion and are just parts of a predictable machine. Newton feared that this notion of "everything is predetermined" would lead to atheism. This theory was undermined by the second law of thermodynamics ( the total entropy of any isolated thermodynamic system tends to increase over time, approaching a maximum value) and quantum physics with its unpredictable random behavior.
    • Abdelrahman Ogail
       
      "God's only contribution to the universe was to set everything in motion, and from there the laws of science took hold and have governed every sequence of events since that time" <-- ???
veera90

Key Home Automation Technologies that Shape the Industry - 0 views

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    Business enterprises and companies with effective automation endeavors make it a strategic priority to augment employees and customer experience, and they use automation to do so. Just pursuing automation technologies to lower expenses is not adequate. To achieve success while scaling new and latest technologies, organizations should focus on the individuals involved (both employees and customers), commit to revamping current processes, and create new skill sets within the workforce to follow more distinct and innovative working methods.
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.
Justin Pierce

The Most Excellent Bookkeeping Services - 2 views

When I was still single, I had all the time to manage my gift shop. But when I got married a year ago, I found it really hard to give equal attention to my business as well as to my roles as a wife...

started by Justin Pierce on 02 Oct 12 no follow-up yet
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

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

Design pattern - Wikipedia, the free encyclopedia - 0 views

  • A pattern must explain why a particular situation causes problems, and why the proposed solution is considered a good one. Christopher Alexander describes common design problems as arising from "conflicting forces" -- such as the conflict between wanting a room to be sunny and wanting it not to overheat on summer afternoons. A pattern would not tell the designer how many windows to put in the room; instead, it would propose a set of values to guide the designer toward a decision that is best for their particular application. Alexander, for example, suggests that enough windows should be included to direct light all around the room. He considers this a good solution because he believes it increases the enjoyment of the room by its occupants. Other authors might come to different conclusions, if they place higher value on heating costs, or material costs. These values, used by the pattern's author to determine which solution is "best", must also be documented within the pattern. A pattern must also explain when it is applicable. Since two houses may be very different from one another, a design pattern for houses must be broad enough to apply to both of them, but not so vague that it doesn't help the designer make decisions. The range of situations in which a pattern can be used is called its context. Some examples might be "all houses", "all two-story houses", or "all places where people spend time." The context must be documented within the pattern. For instance, in Christopher Alexander's work, bus stops and waiting rooms in a surgery are both part of the context for the pattern "A PLACE TO WAIT."
    • Islam TeCNo
       
      This is Not a CS related articile ....check this link !! http://en.wikipedia.org/wiki/Design_pattern_(computer_science)
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    Design Patterns
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    Design Patterns
Janos Haits

The Freenet Project - /index - 0 views

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    Freenet is free software which lets you anonymously share files, browse and publish "freesites" (web sites accessible only through Freenet) and chat on forums, without fear of censorship. Freenet is decentralised to make it less vulnerable to attack, and if used in "darknet" mode, where users only connect to their friends, is very difficult to detect. Share files, chat on forums, browse and publish, anonymously and without fear of blocking or censorship! Then connect to your friends for even better security! "
Janos Haits

A Million Dollar Request for Social Networks | Blockstack - 0 views

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    "It's time for a new breed of social networks - where power is taken back from a single authority and control is returned to you, to me, to all of us. It's time to decentralize social networks.  This is a movement toward greater personal freedom, but it takes an empowered community to build this future."
veera90

Best Pharmacovigilance Services | Pharmacovigilance Professionals | ACL Digital Life Sc... - 0 views

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    From proof-of-concept to post-marketing surveillance services, you can depend on our PV experts to efficiently work through the entire scope of Pharmacovigilance activities. We offer a high level of expertise and assist in meeting the highest standards of applicable national and global regulations. The experts at ACL Digital can easily customize safety monitoring services to suit your specific business requirements. Most biopharmaceutical companies have distinct and demanding clinical safety requirements as per the directions of regulatory agencies. You can depend on our PV specialists who plan safety and pharmacovigilance services accordingly that fit the needs of both your product and study - we adhere and adapt to your processes and are flexible enough to do it the right way.
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