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Search of Web Resources : Tools, Techniques and
Strategies
A Brief Summary of the Evolution of the Internet
1945
Memex Conceived
1945
WWWCreated
1989
MosaicCreated
1993
A Mathematical
Theory of Communication
1948
Packet Switching Invented
1964SiliconChip1958
First Vast ComputerNetwork
Envisioned1962
ARPANET1969
TCP/IPCreated
1972
InternetNamed
and Goes
TCP/IP1984
HypertextInvented
1965
Age ofeCommerce
Begins1995
Top 10 Internet use Countries in Asia
Web 1.0. and Lib1.0 – ”Read-Only”
Web 2.0 & Lib2.0 – ”Read/Write web/Lib.”
”Architecture of participation”
Searching Tools • Search Engines • Meta Search Engines• Directories (General)• Scholarly Communication Directories
– DOAJ, DOAR, ROAD• Subject Gateways • Discipline Oriented Portals• Digital Libraries• IRs
The good news….
• People are reading and writing more than ever…but not in the traditional way. It’s the internet, blogging, Facebook, twitter…
Planning for Effective Searching
Step-1 Defining the Problem: Using Concept MapsStep-2 Select the keywords from the titleStep-3 Write down the synonymous terms. Step-4 Decide the Scope of your SearchStep-5 Identify the relevant sources
(search engine, Databases, gateways, websites)Step-6 Build your Search Query using search techniqueStep-7 Conduct Mock SearchStep-8 Evaluate Answers (Check the relevance)Step-9 Refine your search
(till you get the required information)Step-10 Display the Answers in more details
Top Level Domains.edu—higher education.com—commercial.gov—government agency.mil—military.org—general noncommercial organization.net—computer network.k-12—elementary and secondary schools
.in and .uk and .us. etc., are countries domain names
Simple IR System
IRSystem
Query String
Documentcorpus
RankedDocuments
1. Doc12. Doc23. Doc3 . .
12
Web Search System
Query String
IRSystem
RankedDocuments
1. Page12. Page23. Page3 . .
Documentcorpus
Web Spider
Problems with Keywords
• May not retrieve relevant documents that include synonymous terms.– restaurant vs. café– India vs. Bharath– Apple (company vs. fruit)
The Google Generation
• User are used to single search boxes like Google and Amazon which give instant satisfaction
• Google is the number one search tool for most academics and students
Low quality information rejected by print media entering into Internet
And Google Scholar• Launched to “allow and enable users to
search for scholarly literature located across the Web” (Anurag Acharya, Google Scholar)
• A slice of Google from the open web that is scholarly, plus as much publishers’ material that Google can crawl over, display and index
Google Scholar• GS has harvested metadata from various
journal publishers so users can access from one interface. Includes many open access journals e.g BioMed Central
• Includes content from at least 29 top scholarly publishers including some from the CrossRef search pilot project, inc. Blackwell, IEEE, Nature Publ. Group, Springer and Wiley.
• Links to material in institutional repositories and new digitisation initiatives like Google Print initiative at Bodleian and JISC Common Information Environment
• Links to ingenta• Links to OCLC WorldCat and gives
locations for individual items
How good are citations on Google Scholar?
• Free and variable in coverage =Potentially useful and important but not comparable to those in Web of Science or SCOPUS
• Citations are interfiled with other records• Can be confusing to use• Records are scraped from full text taken into GS and results do
not match Web of Science, and references are sometimes incomplete
• “Cited by” only includes articles indexed within its database• Items with more citations from other highly ranked sources
come first• Much work remains to be done to make it a fully
recommendable resource
Search Techniques
• Quotes: (“ “)• Placing the words within quotation marks (“ “)
creates phrases, it returns match only when the engine finds the exact word sequences.
Asterisk: (*) or Truncation • An asterisk (*) is also known as a wild card;
– These search techniques retrieve information on similar words by replacing part of the word with a symbol usually a * or ?. However, different databases use different symbols, so check what is used.
• Example: In truncation the end of the word is replaced Chem* would result Chemistry, Chemical, Chemotherapy etc.– In wildcard searching, letters from inside the word are
replaced.• For example wom*n will retrieve the terms woman and women.
Search for specific types of files
• Such as PDFs, PPTs, doc, etc., by adding filetype: and the 3-letter file abbreviation.
• Example: “information literacy”: ppt“digital library”: pdf“user education”: doc
Entity Search Engines • Information is everywhere. Different search engines
extract different types of information from various databases when we give queries to them.
• Some entities, for instance, person, organization, location, events, time, etc.
• But it is a laborious job for us to find out specific or exact information about entities from present search engines.
• Entity Cube, Okkam Entity Name System, Sindice, wolframAlpha, etc. are the examples of entity search engines, which retrieve information about entities
Open Access Web-Resource
Meta-Search Engines• Meta search tools provide a common interface and
conduct searches in many search engines simultaneously and return results in a uniform format
• Meta search tools (remote sites):– Dogpile (www.dogpile.com)
– MetaCrawler (www.metacrawler.com)
– Ixquick (www.ixquick.com)
– ProFusion (www.profusion.com)
Open Access Scholarly Resources
Online Reference Sources
Federated Search Engine
Open Access Books
OpenBook Publishers
Open Monographs: examples
Open Humanities – Books & Journals
OA-Lecture Videos
Ekalavya portal• The Ekalavya portal aims at a free
exchange of knowledge and ideas, by placing all the relevant academic material in the open source, thus making considerable contribution to society.
• The Ekalavya project has also developed an Open Source Educational Resources Animation Repository (OSCAR) and provides web-based interactive animations for teaching various concepts and technologies
Web Directories and
Subject Gateways
Discipline Oriented/Subject Portal