Generic Form

Generic form: protocol://server.machine.name:port/dir/file Examples: Use FTP, login as "anonymous" change dir to /home/smith, get file budget.wk1 ftp://eau.ww.eesd.gov.calgary/home/smith/budget.wk1

Use gopher, go to top menu of "gopher.voa.gov" machine gopher://gopher.voa.gov

Use the Web "Hypertext Transfer Protocol" (HTTP), ask machine "www.apple.com" for file "index.html" in the top directory. http://www.apple.com/index.html

Read the file "to_mom.txt" in C:\data\letters on your machine. file:/data/letters/to_mom.txt

The URL for this presentation is: http://www.cuug.ab.ca:8001/~branderr/csce.html

(everyone with a Web connection can go home now)

8. Uniform Resource Locators (URLs) URLs, or Uniform Resource Locators, are the method by which documents or data are addressed in the World Wide Web. The URL contains the following information: • • • •

the internet name of the site containing the resource (document or data) the type of service the resource is served by (eg, HTTP, Gopher, WAIS) the Internet port number of the service. If this is omitted the browser assumes a commonly accepted default value. the location of the resource in the directory structure of the server.

URLs are more sophisticated than this brief introduction would imply. For more detail, have a look at the URL overview document, found at the URL: http://www.w3.org/hypertext/WWW/Addressing/URL/Overview.html.

8.0 Structure of an URL The following is an outline of the most common form of a URL: http://www.address.edu:1234/path/subdir/file.ext | | | | | |service | | | | |____ host ______| | | | | |

|port| | | file and | |_ resource details _|

8.0.1 Service The above figure gives a general outline of URL structure. This outline if followed by most, but not all, URLs. Specific cases are discussed in subsequent sections. The first part is the service specifier, (here HTTP service) which specifies the access method. Specifically this is the part before the colon. Some examples of services are: http:, gopher:, wais: and ftp:.

8.0.2 Address and Port number The second part is usually the internet address of the server, indicated by the double forward slash (//). This address can also contain the (optional) port number the service listens at. The full name is then specified by a string like //www.address.edu:1234/, where :1234 means Port number 1234. If you want to use the default port number you can leave out both the colon and the number, i.e. //www.address.edu/.

8.0.3 Resource Location The forward slash after the host and port specifications indicates the end of the address and the beginning of the specification for the file/resource to be accessed. This field varies depending on the service being accessed. A few simple examples follow: more detailed ones are given in the documents listed below.

8.0.4 Special Cases In some cases the internet address and resource location are omitted. The common examples of this are news: (for accessing Usenet news group information) and mailto: (for sending e-mail).

8.0.5 Query Strings The URL scheme also allows you to include a query string that is to be passed to the designated URL. This is indicated by placing a question mark at the end of the URL, followed by the desired query string. For example: http://www.where.edu/cgi-bin/program?query_string_data

The query string must be specially encoded, using what is known as URL encoding. This is discussed in the CGI documentation found at NCSA and elsewhere in this document collection.

8.0.6 Some Simple URL Examples

http://info.cern.ch/hypertext/WWW/Addressing/URL/Overview.html

Retrieve the named HTML document from the CERN http server running on the default port.

gopher://gumby.brain.headache.edu:151/7fonebook.txt

Access the searchable index 'fonebook.txt' from the named gopher server, running on port number 151. news:alt.rec.motorcycle

Access the newsgroup alt.rec.motorcycle. For detailed information on the different URL formats see: • • • • • • •

HTTP Gopher FTP WAIS Telnet/tn3270/rlogin Usenet Mailto

Description of URLdemo The major tasks performed by URLdemo are: 1. Construct a URL object. The example first calls a constructor on java.net.URL and assigns the resulting object to variable url. The URL constructor takes a single argument, the name of the URL to be accessed, as a string. The constructor checks whether the input URL has a valid form. url = java.net.URL(... 'http://www.mathworks.com/support/tech-notes/1100/1109.html')

2. Open a connection to the URL. The second statement of the example calls the method, openStream, on the URL object url, to establish a connection with the Web site named by the object. The method returns an InputStream object to variable, is, for reading bytes from the site. is = openStream(url);

3. Set up a buffered stream reader. The next two lines create a buffered stream reader for characters. The java.io.InputStreamReader constructor is called with the input stream is, to return to variable isr an object that can read characters. Then, the

java.io.BufferedReader constructor is BufferedReader object to variable br. A

called with isr, to return a buffered reader provides for efficient

reading of characters, arrays, and lines. isr = java.io.InputStreamReader(is); br = java.io.BufferedReader(isr);

4. Read and display lines of text. The final statements read the initial lines of HTML text from the site, displaying only the first 4 lines that contain meaningful text. Within the MATLAB for statements, the BufferedReader method readLine reads each line of text (terminated by a return and/or line feed character) from the site. for k = 1:288 s = readLine(br); end

% Skip initial HTML formatting lines

for k = 1:4 s = readLine(br); disp(s) end

% Read the first 4 lines of text

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Running the Example When you run this example, you see output similar to the following. (Note that the line breaks were changed to fit the output in the documentation).

This technical note provides an introduction to vectorization techniques. In order to understand some of the possible techniques, an introduction to MATLAB referencing is provided. Then several vectorization examples are discussed.

This technical note examines how to identify situations where vectorized techniques would yield a quicker or cleaner algorithm. Vectorization is ofen a smooth process; however, in many application-specific cases, it can be difficult to construct a vectorized routine. Understanding the tools and

Back to Top Introduction to Programming Examples

Provide feedback about this page Example — Finding an Internet Protocol Address

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URL usage examples Jump To: Also found in:

Link/Cite Webster's Dictionary ·

Webster's Telecom Dictionary

Ads by Google Perfect Pitch Scams - Shocking news about Perfect Pitch advertisers on this page ... RichardBosworth.org

English Dictionary - Look Up Dictionary Terms Instantly! Free Reference Dictionary Toolbar. Dictionary.alot.com Human Rights Education - Raise Human Rights Awareness To Our Youth. Get Free DVD & Info Kit YouthForHumanRights.org Preposition: of •

release: If you would like a release removed please send an email to [email protected] together with the url of the release.

•

page: The CASTLE toolkit also enables modification of your test file, by entering the URL of the page where you have published your test.

•

document: This will become the last part of the full internet URL of the web link document.

Converse of object •

paste: Usually this involves cutting and pasting the URL of the RSS feed into your relevent area of your news reader.

•

redirect: URL redirects Every external URL entered into database so we can log who's going where and how many times.

•

enter: Enter the url to the site you want to create a web link to.

•

specify: For sealed packages, the additional URL specifies the code source URL from which the package was loaded.

•

parse: First tries to parse the URL 's toExternalForm as a URI and create the File object from that URI.

•

follow: Click the radio button labeled " Respond with the following url.

Adjective modifier •

permanent: A great debate ensued about whether there was value in developing a DOI when a permanent URL could achieve the same degree permanence.

•

exact: Copy exact URL 's of groups, message boards, photos, etc to report to them.

•

specified: A second form of this method takes a URL and will return true if the package is sealed with respect to the specified URL.

•

absolute: The question for this article is whether or not you should use " absolute url 's " or " relative url's " ?

•

relative: The question for this article is whether or not you should use " absolute url's " or " relative url 's " ?

•

valid: Each Column value should be a valid URL to an image file.

Modifies a noun •

portlet: URL portlet An Oracle9 i AS Portal portlet that displays the contents of a Web page specified by a URL.

Noun used with modifier •

netfuture: You may also redistribute individual articles in their entirety, provided the NetFuture url and this paragraph are attached.

•

blog: The guru is more than happy to help, you orchestrate several virtual classroom sessions and send out the flying guru blog URL.

•

destination: What happens is that clicking a link on the map takes me to an intermediate page which has the final destination page URL.

•

web: This may include your name, email address and web site URL.

The word usage examples above have been gathered from various sources to reflect current and historical usage. They do not represent the opinions of YourDictionary.com. Link to this page:

Cite this page:

MLA Style "URL." Usage Examples. 2009 • •

Your Dictionary. 30 July 2009 <www.yourdictionary.com/examples/url>

APA Style URL. (2009). In Usage Examples

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Human Rights Education - Raise Human Rights Awareness To Our Youth. Get Free DVD & Info Kit YouthForHumanRights.org Measure Market Volatility - Free Forex Tips to Help You Succeed Build your Forex toolkit. Make Pips www.Babypips.com/FreeTips Examples of strong passwords - Can someone guess your password? Protect yourself now www.SmartPlanet.com Browse dictionary definitions near URL 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

urinous urinose urinoscopy urinometry urinometer urinoma urinogenous urinogenital urinogenital urino-

1. URL or Uniform Resource Locator 2. Urmia 3. urn 4. uro5. uro6. urobilin 7. urobilinemia 8. urobilinogen 9. urobilinuria 10. urochordal

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As a message Information is a term with many meanings depending on context, but is as a rule closely related to such concepts as meaning, knowledge, instruction, communication, representation, and mental stimulus. Simply stated, information is a message received and understood. In terms of data, it can be defined as a collection of facts from which

conclusions may be drawn. There are many other aspects of information since it is the knowledge acquired through study or experience or instruction. But overall, information is the result of processing, manipulating and organizing data in a way that adds to the knowledge of the person receiving it. Information is the state of a system of interest. Message is the information materialized. Information is a quality of a message from a sender to one or more receivers. Information is always about something (size of a parameter, occurrence of an event, value, ethics, etc). Viewed in this manner, information does not have to be accurate; it may be a truth or a lie, or just the sound of a falling tree. Even a disruptive noise used to inhibit the flow of communication and create misunderstanding would in this view be a form of information. However, generally speaking, if the amount of information in the received message increases, the message is more accurate. This model assumes there is a definite sender and at least one receiver. Many refinements of the model assume the existence of a common language understood by the sender and at least one of the receivers. An important variation identifies information as that which would be communicated by a message if it were sent from a sender to a receiver capable of understanding the message. In another variation, it is not required that the sender be capable of understanding the message, or even cognizant that there is a message, making information something that can be extracted from an environment, e.g., through observation, reading or measurement. Communication theory provides a numerical measure of the uncertainty of an outcome. For example, we can say that "the signal contained thousands of bits of information". Communication theory tends to use the concept of information entropy, generally attributed to Claude Shannon, see below. Another form of information is Fisher information, a concept of R.A. Fisher. This is used in application of statistics to estimation theory and to science in general. Fisher information is thought of as the amount of information that a message carries about an unobservable parameter. It can be computed from knowledge of the likelihood function defining the system. For example, with a normal likelihood function, the Fisher information is the reciprocal of the variance of the law. In the absence of knowledge of the likelihood law, the Fisher information may be computed from normally distributed score data as the reciprocal of their second moment. Even though information and data are often used interchangeably, they are actually very different. Data is a set of unrelated information, and as such is of no use until it is properly evaluated. Upon evaluation, once there is some significant relation between data, and they show some relevance, then they are converted into information. Now this same data can be used for different purposes. Thus, till the data convey some information, they are not useful and therefore not information.

nformation technology (IT), as defined by the Information Technology Association of America (ITAA), is "the study, design, development, implementation, support or management of computer-based information systems, particularly software applications and computer hardware."[1] IT deals with the use of electronic computers and computer software to convert, store, protect, process, transmit, and securely retrieve information. Today, the term information technology has ballooned to encompass many aspects of computing and technology, and the term has become very recognizable. IT professionals perform a variety of duties that range from installing applications to designing complex computer networks and information databases. A few of the duties that IT professionals perform may include data management, networking, engineering computer hardware, database and software design, as well as the management and administration of entire systems. When computer and communications technologies are combined, the result is information technology, or "infotech". Information technology is a general term that describes any technology that helps to produce, manipulate, store, communicate, and/or disseminate information. Presumably, when speaking of Information Technology (IT) as a whole, it is noted that the use of computers and information are associated. The term information technology is sometimes said to have been coined by Jim Domsic of Michigan in November 1981.[citation needed] Domsic, who worked as a computer manager for an automotive related industry, is supposed to have created the term to modernize the outdated phrase "data processing". The Oxford English Dictionary, however, in defining information technology as "the branch of technology concerned with the dissemination, processing, and storage of information, esp. by means of computers" provides an illustrative quote from the year 1958 (Leavitt & Whisler in Harvard Business Rev. XXXVI. 41/1 "The new technology does not yet have a single established name. We shall call it information technology.") that predates the so-far unsubstantiated Domsic coinage. In recent years ABET and the ACM have collaborated to form accreditation and curriculum standards for degrees in Information Technology as a distinct field of study separate from both Computer Science and Information Systems. SIGITE is the ACM working group for defining these standards.

Artificial intelligence From Wikipedia, the free encyclopedia Jump to: navigation, search "AI" redirects here. For other uses, see Ai. For other uses, see Artificial intelligence (disambiguation).

A facial recognition system is an example of artificial intelligence Artificial Intelligence (AI) is the intelligence of machines and the branch of computer science which aims to create it. Major AI textbooks define the field as "the study and design of intelligent agents,"[1] where an intelligent agent is a system that perceives its environment and takes actions which maximize its chances of success.[2] John McCarthy, who coined the term in 1956,[3] defines it as "the science and engineering of making intelligent machines."[4] The field was founded on the claim that a central property of human beings, intelligence —the sapience of Homo sapiens—can be so precisely described that it can be simulated by a machine.[5] This raises philosophical issues about the nature of the mind and limits of scientific hubris, issues which have been addressed by myth, fiction and philosophy since antiquity.[6] Artificial intelligence has been the subject of breathtaking optimism,[7] has suffered stunning setbacks[8] and, today, has become an essential part of the technology industry, providing the heavy lifting for many of the most difficult problems in computer science.[9] AI research is highly technical and specialized, so much so that some critics decry the "fragmentation" of the field.[10] Subfields of AI are organized around particular problems, the application of particular tools and around longstanding theoretical differences of opinion. The central problems of AI include such traits as reasoning, knowledge, planning, learning, communication, perception and the ability to move and manipulate objects.[11] General intelligence (or "strong AI") is still a long-term goal of (some) research[12], while many researchers no longer believe that this is possible. An expert system is software that attempts to reproduce the performance of one or more human experts, most commonly in a specific problem domain, and is a traditional application and/or subfield of artificial intelligence. A wide variety of methods can be used to simulate the performance of the expert however common to most or all are 1) the creation of a so-called "knowledgebase" which uses some knowledge representation formalism to capture the Subject Matter Experts (SME) knowledge and 2) a process of gathering that knowledge from the SME and codifying it according to the formalism, which is called knowledge engineering. Expert systems may or may not have learning components but a third common element is that once the system is developed it is proven by being placed in the same real world problem solving situation as the human SME, typically as an aid to human workers or a supplement to some information system.

As a premiere application of computing and artificial intelligence, the topic of expert systems has many points of contact with general systems theory, operations research, business process reengineering and various topics in applied mathematics and management science.

Contents

Neutral networks From Scholarpedia This article has not been peer-reviewed or accepted for publication yet; It may be unfinished, contain inaccuracies, or unapproved changes. Author: Dr. Inman Harvey, EASy Group, Informatics, University of Sussex The dynamics of evolutionary change in biology, and of search in evolutionary optimization, can be visualized as a population climbing the peaks of a fitness landscape, where height represents fitness.

Figure 1: Traditional picture of a fitness landscape without neutrality Genetic changes such as mutations are visualized much as movements north-south or east-west on a 2-dimensional geographical map, but scaled up to a dimensionality corresponding to the number of genes. Some fitness landscapes may contain 'ridges' or level connected pathways of the same fitness -- connected via single potential mutations -- and these are Neutral Networks. If such Neutral Networks percolate widely through a fitness landscape, they can transform the evolutionary dynamics. Populations can escape what otherwise might have been local optima by random genetic drift, thus giving opportunities for chancing upon portals to regions of higher fitness.

Figure 2: A fitness landscape with neutrality: red 'portals' offer access between 3 neutral networks Biologists analyse the extent to which Neutral Networks may or may not exist in practice to any significant extent in the fitness landscapes implicit in biological systems under natural selection. At the smaller end of the scale, RNA Neutral Networks correspond to those mutations at base-level that do not affect the shapes that the RNA folds into, and hence do not affect their function or fitness (Schuster et al 1994). At the larger end of the scale, looking at macro-evolution,all possible genotypes associated with a viable species can be allocated a nominal fitness of one, and all nonviable genotypes a nominal fitness of zero;this gives a `holey adaptive landscape` on which to visualise possible microevolutionary pathways (Gavrilets 2004). Formal investigations of Neutral Networks study the dynamics of evolution on abstract fitness landscapes that include varying degrees of neutrality: how does neutrality relate to measures of ruggedness (Barnett 2001)? What is the expected waiting time traversing a ridge before finding a portal to a fitter region (van Nimwegen et al, 1999, 2000)? Practitioners of evolutionary computation are interested in analysing the extent to which neutral networks may or may not exist in practice in the fitness landscapes implicit in the problems where they are trying to optimise some function. There is evidence that in many difficult real problems neutral networks are very significant, and this has implications for how one should best design an evolutionary algorithm (Thompson and Harvey 1996).

Robotics From Wikipedia, the free encyclopedia Jump to: navigation, search

The Shadow robot hand system Robotics is the engineering science and technology of robots, and their design, manufacture, and application.[1] Robotics is related to electronics, mechanics, and software.[2] The word robot was introduced to the public by Czech writer Karel Čapek in his play R.U.R. (Rossum's Universal Robots), published in 1920. The first recorded use of the term was by Isaac Asimov in his 1941 science fiction short-story Liar!"[3]