Презентация на тему: " Technical Means of Informational Technologies: Network Technologies Lecture 2 on discipline of "Information technologies in pharmacy" for 1st year students." — Транскрипт:
Technical Means of Informational Technologies: Network Technologies Lecture 2 on discipline of "Information technologies in pharmacy" for 1st year students of pharmaceutical faculties
Plan of Lecture 1.Basic Internet Concepts 2.Structure of the Internet 3.Types of Information 4.Evaluation of Information 5.Search Tools & Techniques 6.Researching Health / Biomedical Information 7.Managing Internet Resources
Basic Internet Terminology What is the Internet? Connecting of Computer Networks Telecommunications Protocols Services Information Networks Libraries Research Centers
The Internet is a network of computers around the world that are linked together by telecommunications in order to share information. It is a network of computer networks. Different types of computers make up the network. Some computers contain information (host computers) or servers, others (clients) access the host or server to retrieve needed information. Basic Internet Terminology
Local Area Network (LAN): A LAN is two or more connected computers sharing certain resources in a relatively small geographic location, often in the same building. Examples include home networks and office networks. There are two main types of computer networks A Local Area Network (LAN)
Wide Area Network (WAN): A WAN typically consists of two or more LANs. The computers are farther apart and are linked by telephone lines, dedicated telephone lines, or radio waves. The internet is the largest Wide Area Network (WAN) in existence. A Wide Area Network (WAN) There are two main types of computer networks
Servers and Clients A server with multiple clients A server is a computer that "serves" many different computers in a network by running specialized software and storing information. For example, web pages are stored on servers. When you access a web page, your computer is acting as a client. A client runs familiar software such as web browsers or software, and it communicates with the server to get the information it requires.
The World Wide Web (WWW) When most people think of the internet, the first thing they think about is the World Wide Web. Nowadays, the terms "internet" and "World Wide Web" are often used interchangeably - but they're actually not the same thing. The internet is the physical network of computers all over the world. The World Wide Web is a virtual network of web sites connected by hyperlinks (or "links"). Web sites are stored on servers on the internet, so the World Wide Web is a part of the internet.
The URL (Uniform Resource Locator) is the global address of documents and other resources on the web e.g. The first part of the address indicates which protocol to use e.g. http. The second part of the address identifies the domain name or the internet address where the information is located. Basic Internet Terminology
Each computer on the network has a unique address, the Internet Protocol address (IP). It is made up of lots of servers and clients that hold and exchange information all over the world. The network is self-organizing and self- governing. There is no group or individual that heads the network. The computers are able to communicate with each other because they use a common set of rules or protocols. An IP address is a unique address that certain computer use in order to identify and communicate with each other on a computer network utilizing the Internet Protocol standard (IP) - in simpler terms, a computer address. Basic Internet Terminology
The protocols Transmission Control Protocol / Internet Protocol (TCP/IP) allows the connection and exchange of information between computers. There are a number of Internet protocols that make communication and information retrieval possible on the WWW. Basic Internet Terminology
Internet Protocols & Services SMTP TCP/IP FTP HTML HTTP TELNET
SMTP (Simple Mail Transfer Protocol) makes the distribution of electronic messages between computers possible. TCP/IP (Transmission Control Protocol/Internet Protocol) makes the transmission of data through the network possible. FTP (File transfer Protocol) transfers data from one computer to another through a network, such as the Internet. Internet Protocols include:
HTML (HyperText Markup Language) used to create documents on the World Wide Web) HTTP (HyperText Transfer Protocol) transmits hypertext over networks. It is the protocol of the WWW. TELNET make it possible to login to a host computer and execute instructions. Internet Protocols include:
The Internet is used by students, researchers and the general population to satisfy their information needs. An Internet user has access to a wide variety of services such as: Electronic Mail File Transfer Information Resources (electronic databases, Journals, books) Discussion groups Multimedia News Services. Information Networks (contain information that is communicated through the WWW) Internet Services
Network of Information Networks The Internet contains a network of libraries and information systems in a hierarchy. At the lowest level there are local library networks, such as university libraries and other types of information networks, which are connected to regional (example EU Commission) and national networks. The National Library network is a national network. The WHO library is an example of an International Library Network.
Library Networks Local - A university, hospital, or research institute Regional – A group of universities National - A country wide network International – The WHO Library
The Internet Address or URL This page is being viewed in the Internet Explorer Browser. Browsers allow computers to read Hyper Text Mark-up Language OR HTML The Address or URL is typed in here.
Entering a URL address in the address box After Entering a URL address in the address box click go or hit the RETURN key. In this example we have entered for the WHO website
Hypertext links Links to other pages (Hypertext) are usually underlined or highlighted with different colour.
Forward and back navigation buttons The arrow buttons on the tool bar allow users to move back and forward to pages within the website.
Home page button The house icon (the HOME button) on the tool bar will take you back to the browsers default Home Page.
What type of Information does the Internet contain? Bibliographic Information (in the form of Library catalogs) Multimedia (Audio, Video and graphical sources of information) Reference Tools such as Encyclopedias, Dictionaries, Handbooks and others Journals, Newspapers & Magazines Databases
Sources of Information Academic Institutions Government Agencies Publishers Commercial - Proprietary Databases Non Profit Professional organizations International Agencies (http://www.who.int/tdr/)
Sources of Information Academic Institutions make their library catalogs and other vital information accessible through their web sites. Government agencies publish a lot of information directly or through research centers which they make accessible through the web. Publishers of information resources provide access to their products through the web Non profit professional organizations also make their scholarly publications accessible. International agencies provide access to their publications as well.
Internet Search Tools Which tools are needed for searching? Browsers Directories Search Engines Meta Search Engines Invisible or Deep Web
Browsers Browsers are computer programs that allow you to navigate the web. These are the main browsers for the WWW: Internet Explorer (IE) Mozilla Firefox Opera Browsers access the documents stored on the WWW and display them for use.
Directories What is a Directory? A file used to organize internet resources into categories. Types of Directories General Cover many subjects ( e.g. Subject Directories. Cover specific subjects
Search Engines What are search engines? A search engine is a searchable database of Internet files, compiled by a computer program which creates an index from the collected files. There is no selection criteria for selection unlike in subject directories. Components of a search engine Spider or Crawler – a computer program that crawls through the web from link to link identifying and reading pages. Index – Database that contains a copy of each web page collected by the crawler.
Software that allows search and retrieval of information usually returns the results in some ranked order based on relevance. Search engines offer the next ways in which search can be done: typing the search terms into a search box like in Google (http://www.google.com) queries can be entered in natural language in form of questions as in Ask Jeeves (http://sp.ask.com/docs/help/) Many search engines allow a combination of search options. There are several search engines some better than others. Searchers usually have a favorite search engine that they use more often. Search engine mechanism
The Google search engine This is the Google search engine. Type your query into the Google search box and click on the Google Search button
Search results on Google This is how Google presents the results of your search. Follow the links to the websites you wish to visit.
Meta Search Engines What is a Meta Search Engine? Meta Search Engines search multiple sets of individual search engines and web directories simultaneously. They provide a quick way for finding out which search engines are retrieving the best results for a search. They usually return a list drawn from the top of search engine lists, the results tend to be more relevant. Examples Dogpile (http://www.dogpile.com/) Metacrawler (http://www.metacrawler.com/index.html)
Meta Search Engines Why Use Meta Search Engines? Meta Search Engine are used for: Locating people Quickly locating information on a simple topic
Invisible Web or Deep Web What is the Invisible Web? The Invisible or Deep Web is the vast amount of searchable databases that are not accessible to search engines and other search tools for technological reasons. The information found in the Invisible Web is made up of specialized databases, indexes, journal contents and other proprietary databases. This type of information is of particular value for academic research.
Invisible Web or Deep Web Google and other search engines can be used to locate searchable databases by searching a subject term and the word "database". If the database uses the word database in its own pages, you are likely to find it in Google. The word "database" is also useful in searching a topic in the Yahoo! directory, because they sometimes use the term to describe searchable databases in their listings. Examples: plane crash database toxic chemicals database
Web Search Techniques Types of Searches Browsing (Involves following links to find relevant information.) Keyword Searching (Typing search terms, keywords, title, author or any other field. It Is supported by most search tools.) Full Text Searching (Searching proximity operators such as NEAR or ADJ are used rather than Boolean Operators. Field Searching is very useful in limiting search results in full text databases.)
Boolean Searching Full Boolean Searching requires the use of logical operators between the search terms. Predetermined language is used in a user fill-in template. Search engines support Boolean searching. However search engines tend to have a default Boolean Logic.
Full Boolean Searching Use Logic Operators AND OR NOT The default can be either AND logic or OR logic. It is important to determine which logical operator is the default for the search engine you are using. Most search engines accept a plus sign + in front of the search term for AND logic, and - for a NOT logic. Relevancy Ranking is the sorting of the results of the search so that the most relevant documents are listed first. Many search engines offer relevancy ranking in search results
AND Operator Query: Information on Malaria AND Parasite MalariaParasite
OR Operator Query: Malaria OR Parasite MalariaParasite
NOT Operator Query: Parasite NOT Malaria ParasiteMalaria
Advanced Searching Techniques: Tips Truncation allows the search for a root word and all of its endings including plurals. The symbol used for truncation in most search engines is the asterisk (*). The help feature will give the information on using truncation in each search engine.
Advanced Searching Techniques: Tips Proximity Searching (searching for terms next to each other) Phrase searching is an option that allows for searching for words within a sentence or paragraph Near operator allows searching for words within a certain number of words from each other ADJ operator allows to locate records in which a field contains all of the search terms adjacent to each other and in the order they were entered
Advanced Searching Techniques: Tips Case sensitivity (Search engines are case-sensitive in different ways. Some ignore capitalization, these ones are called case-insensitive. Some of them require capitalization, and are called case-sensitive)
More Search Techniques Field Specific Searching Title Date URL Language Restrictions
Evaluating Web Information Since the Internet is a self – publishing medium, the information is not suitable for professionals. Information retrieved from the Internet must be evaluated and analyzed for appropriateness for research purposes. Criteria for Evaluation Accuracy Authority Currency Coverage Objectivity Criteria for evaluating Health Information information.html
Free Internet Resources Full-text Ready reference material Library Catalogues Journals Government Information Research Databases Publishers Databases Discussion groups News
Health Information in the Internet Directories - Subject Directories - Health Directories Databases - Health Electronic Journals
Databases Government –http://www.nlm.nih.gov/hinfo.html International Health Organizations –http://whqwings.who.int/RIS/RISWEB.isa –http://www.who.int/tdr/topmenu/databases.htm Educational Institutions –http://highwire.stanford.edu/lists/freeart.dtl
Searching within the NLM website This is the National Library of Medicine (NLM) database. You can search the site from the Search Box.
HireWire Press free article database This the HireWire Press free article database. Users have access to over 740,000 full text articles.
FreeMedicalJournals.com FreeMedicalJournals.com lists journals sites that make their content free to all users. Journals are listed by A-Z, speciality, and language.
BioMed Central BioMed Central is an open access publisher that makes access to published articles freely available to the public. The journals are funded by an author pays model.
PubMed Central PubMed Central is a free archive of articles that have been deposited in this free repository.
Fee-Based Internet Resources Reference Titles Periodical Indexes Electronic Journals Electronic Text Books Online Databases
Managing Internet Resources Creating a list of sites that you find useful is done by using Bookmarks or Favorites. Offline Activity (saving Web pages to view them later when there is no connection to the Internet)
Adding favorites 1 To add a page to Favorites click on the link on the Tool bar.
Adding favorites 2 You can now give your new Favorite a name.
Adding favorites 3 When you select favorites from the tool bar you can see that your page has been added to the list.