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A Mobile World Wide Web Search Engine
Wen-Chen HuDepartment of Computer Science
University of North DakotaGrand Forks, ND 58202-9015
Outline
1. Introduction
2. A web search engine
3. Search engine technologies
4. A mobile web search engine
5. Adaptive viewing the mobile search results
6. Summary
Introductiontroduction
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Worldwide total smartmobile device market
The figure shows the growth in demand for smart mobile devices
including handhelds, wireless handhelds, and smart cellular phones
through 2006, as estimated by the research firm Canalys.
Accessibility of Information on the Web
• Search engine coverage having decreased
• Unequal access
• Out of date
• Information distribution
• 25 billion indexable web pages as of 2006
• Deep web
• Low metadata use
A Web Search Engine System Structure
1. The crawlers (spiders)
2. The index
3. The search and ranking software
Information Provided by HTML Files
• Contents
• Descriptions (metatags)
• Hyperlinked text
• Hyperlinks
• Keywords
• Page structure
• Page title
• Text with different fonts
• The first sentence
Hyperlink Exploration
The creation of a hyperlink by the author of a web page represents an
implicit endorsement of the page being pointed to. This approach is based
on identifying two important types of web pages for a given topic:
• Authorities, which provide the best source of information on the
topic, and
• Hubs, which provide collections of links to authorities.
Information Retrieval: Relevance Feedback
An initial query is usually a wild guess. Retrieved query results are then
used to help construct a more precise query or modify the database
indexes. Two relevance feedback methods, query modification and
indexing modification, can be used to improve the search.
Information Retrieval: Data Classification
The process finds the common properties among a set of objects in a
database and classifies them into different classes, according to a
classification model.
Information Retrieval: Data Clustering
The process of grouping physical or abstract objects into classes of similar
objects is called clustering or unsupervised classification. The document
clustering could be an alternative method of organizing retrieval results.
Metasearch
Metasearch engines automatically and simultaneously query several
Internet search engines, interpret the results, and display them in a uniform
format.
A metasearch engine
usually consists of three
components:
• dispatch mechanism
• interface agents
• display mechanism
An SQL Approach
This approach views the Web as a huge database, where each record
matches a web page, and designs an SQL-like language to support
effective and flexible searches. For example, the query below finds the
documents about “excursions” near WWW6 homepage.
Content-Based Multimedia Search
The goal of the QBIC —
IBM's Query By Image
Content—project is to
help users find and
retrieve pictures or video
by drawing, painting,
sketching, or using other
graphical means.
Mobile Handheld Devices
A handheld device is a small general-
purpose, programmable, battery-powered
computer that can be held in one hand
of a mobile user.
It is different from a desktop or notebook computer:
• mobility,
• low communication bandwidth, and
• limited computing power and resources
such as memory and batteries.
A Handheld Device System Structure
● a mobile operating system ● a mobile CPU
● a microbrowser ● input/output devices
● memory ● batteries
Mobile users
Instructions
Data
I/O bridge
I/O bus
Wireless adapter
Memory bus
Batteries
Mobile CPU Memory
Mobile OS
I/O devices
Microbrowser
System bus
A Mobile Search Engine System Structure
Fast Search &
Transfer’s mSearch
mobile-search
services works with
general Internet
content in formats
accessible by mobile
devices.
Yahoo! Mobile Search
Search — Search the entire Internet and over a
billion images, optimized for your small
screen.
Local Info — The best source for local
business listings, giving you results based on
where you are.
Instant Messages — Text messaging delivers.
Search for anything you need and get results
back by SMS.
Google Mobile Search
Search — Find exactly what you are looking
for by searching through Google's entire index
of web and mobile web pages. And Google
will fit the pages for your device's smaller
screensize.
Local Listings — Search and locate
everything from restaurants to dry cleaners.
Detecting Web Page Structurefor Adaptive Viewing on Devices
A web page is organized into a two level hierarchy with a thumbnail
representation at the top level for providing a global view and index to a
set of sub-pages at the bottom level for detail information.
Opera's Small-Screen Rendering™
With Small-Screen Rendering™, the page is reformatted to fit inside the
screen width and eliminate the need for horizontal scrolling. All the content and functionality is still available, it is only the layout of the page that is changed.
Summary
It is expected the cumulative sales of smartphones will reach 1 billion units
by the first quarter of 2011. Most of the users will use mobile search to
find
mobile pages:
• The technologies used for mobile search are similar to traditional
search.
• Several different languages and incompatible microbrowsers are used
to create and view mobile web pages, which cause confusion and
trouble for mobile search. In the near future, most microbrowsers
will be able to view HTML.
• The major problem faced by mobile search is how well the search
results can be displayed on the small screens of handheld devices.