Transcript PowerPoint Slides - United States Naval Academy

Summer Seminar 2002
Dr. Don Needham (USNA ’83)
Computer Science Department
U.S. Naval Academy
Admin Notes
Restrooms – Next to the elevator
Please sign Name and Address Sheet
Login Procedures
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5.
Press <Ctrl>-<Alt>-<Delete> Keys simultaneously
User name: sseminar
Password: sseminar
Log on to: CS-STUDENTS
Press Ok Button
Agenda
Why Computer Science?
USNA Computer Science Department
Searching the Web
Introduction to HTML
Why Computer Science?
Why consider majoring in Computer Science?
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A truly marketable degree, potential for growth
Can keep current with CS as a Naval Officer
Job availability (both in and out of the Navy!)
The #1 fastest growing field in the world
5 of the 6 richest humans in the world in 1999 made
their fortunes in computer-related fields
Why Computer Science?
Skills you will learn while earning your degree
– Programming skills in languages such as
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C++ (the #1 industry computer language)
Java
LISP / Scheme
Assembler
HTML / XML
– Working familiarity with powerful programming tools and
environments such as
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Microsoft Visual Studio (Visual C++, Visual Basic, InterDev)
Microsoft .NET
J++ Builder.
Linux
Why Computer Science?
Skills you will learn while earning your degree
(cont.)
– Distributed computing solutions
– Networking knowledge ranging from the hardware
level to the application level
– Experience with 2-dimensional and 3-dimensional
graphics
– Programming at the hardware level using assembly
to control registers, input and output devices, etc.
Agenda
Why Computer Science?
USNA Computer Science Department
Searching the Web
Introduction to HTML
USNA Computer Science Dept
USNA Computer Science Department
– B.S. in Computer Science
– Nationally Accredited by the Accreditation Board for
Engineering and Technology (ABET)
– Fourteen faculty members
• Seven Civilian
• Seven Military
USNA Computer Science Dept
USNA Computer Science Department (cont.)
– Strong Core Curriculum
– Opportunities to explore the following areas in depth
• Computer Networks
• Software Engineering
• Artificial Intelligence and Robotics
• Computer Architecture
• Computer Graphics
– For more information, check out our website:
• www.cs.usna.edu
USNA CS Majors
Recent Activities of USNA CS majors:
– Summer Internships
• National Security Agency (NSA)
• Naval Research Lab (Washington DC)
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Information Assurance (Attacked by NSA!)
Beowulf Cluster
Netcentric Warfare (Trident Scholar)
Autonomous Underwater Vehicle competition
AUV Competition
Competing against other universities
July 31st
Sunny Southern California
Goal: To broaden the interest in AUVs and associated
technologies by challenging a new generation of
engineers to perform realistic missions in the
underwater environment
Mission
NAVY ‘02
BEAT ARMY
Camera takes
picture and stores
barcode in file –
the depth of the
barcode is also
stored
UNITED STATES
NAVAL ACADEMY
USNA
Depth Sensor and
Altimeter work
together to figure
out depth of
pinger
Basic Control
Sensors
Desired Course
PC104
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Control
Algorithm
Thrusters
Actual
Course
USNA’s AUV Entry
SEA TRIALS
Watch the AUV in action . . .
Agenda
Why Computer Science?
USNA Computer Science Department
Searching the Web
Introduction to HTML
How big is the Web?
Conservative estimates place Web at 2-3 Billion
pages of information
More liberal estimates place Web near 10 Billion
pages of information
How much of the Web
is covered?
Web Coverage: Summer 2001
1500
1347
250
0
350
500
500
550
575
1000
Millions of
Pages Indexed 500
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gh
Ex
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Go
Search Engines
Google (www.google.com)
– Uses “Link Popularity” algorithm to rank Web pages
– Customizable Toolbar add-on for MS-Internet Explorer
Altavista (www.altavista.com)
– Includes directory results from LookSmart
– Babelfish translation service
Excite (www.excite.com)
– Includes directory results from LookSmart
Search Engines
A Web page database system
– System Elements
• “Spider” or “Robot”
– Software program that visits a Web page, records information within the
page, and follows embedded links to other pages
– Returns to sites on a periodic basis to update Index
• Index (Database)
– Contains copy of desired Web pages found by the Spider
– Contains referencing information based on a set desired criteria to Web
pages scanned by the Spider
• Search Engine
– Finds matches to queries
– Ranks Web pages according to implemented algorithm
Search Engine Queries
Natural Language Queries
– Query looks like a normal question
• What is a black hole?
• Where can I find information about Navy sports?
– Advantage
• No difficult syntax to learn
– Disadvantages
• Imprecise
• Many irrelevant results
Examples
– www.askjeeves.com, www.altavista.com, www.excite.com
Search Engine Queries
Pattern Matching
– Form query using keyword or group of keywords
• Use unique keywords
• Avoid keywords that might be in irrelevant documents
– Search engine returns any page that “contains” these
keywords
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May occur anywhere on the page
Within the first 100 words of the page
In the title of the page
Occur frequently on the page
Improving Search Queries
Capitalize proper nouns and names
Wildcards
– Usually use the “*” character
– Help find:
• Different forms of a word
• Common misspellings
• Alternate spellings
– Examples:
• wish*: Finds wish, wishes, wishful, wishbone
• organi*ation: Finds organisation or organization
Improving Search Queries
Specify “mandatory” keywords
– To require that a word appears on page, use “+”
character
• Example: +peanut +origin
– To ensure a word does not appear on page, use “-”
character
• Example: +peanut +origin -snoopy
Improving Search Queries
Phrase Matching
– Enclose a sequence of words in quotations “phrase”
– Examples
• “Yosemite camping reservations”
• “Ken Griffey”
Improving Search Queries
Restricting Search Domains
– Domain Searches (e.g., .org, .com)
• Domain:edu (MSN)
• host:edu (Alta Vista)
• site:edu (Google)
– Site Searches
• domain:microsft.com (MSN)
• host:microsoft.com (Alta Vista)
• site:microsoft.com (Google)
Agenda
Why Computer Science?
USNA Computer Science Department
Searching the Web
Introduction to HTML
HTML
Hypertext Markup Language (HTML)
– Set of "markup" symbols or codes (tags)
– Inserted in a text file which is intended for display on
a Web browser
– Tells Web browser how to display a Web page's
words and images
Creating HTML Documents
Need:
– A text editor to create an ASCII file with an
extension of .html or .htm (use html for our
purposes)
• Notepad
• Word Processor (save as an ASCII text file)
• HTML Editor
– A Web browser to test your pages
Getting Started
Start Notepad
– Do NOT use WordPad
– Save empty document to
• Click File/Save As…
• Save in: S:\ drive
• File name: May use any name BUT must append .html after name
Start Internet Explorer
– Open file created with Notepad
• Click File/Open…/Browse…
• Select your file
– Browser should appear blank
HTML Syntax
<TAG attribute1=”value1” attribute2=”value2”>Item to be formatted</TAG>
Number of attributes vary (may be none)
Best to put quotes around attribute values
Ending or closing tag same as starting tag with “/” in front of
the tag name
– Not all tags require closing tags
Not case sensitive
– <HR> and <hr> are both okay
Basic HTML Document
Create basic HTML skeleton in
Notepad document
– Only enter the <tags>
<html>
<head>
head elements
</head>
<body>
body elements
</body>
</html>
Creating a Title
The <title> tag
– Goes between <head> and
</head> tags
– Should provide a concise
description of page
– Displayed in title bar of
browser window
– Used as default bookmark
description
– Can affect how document is
indexed by some search
engines
Example
– <title>Text</title>
<html>
<head>
<title>…</title>
</head>
<body>
body elements
</body>
</html>
Update Web Page View
Save Notepad document
– Click File/Save
Refresh browser
– Click View/Refresh
– Title text now appears in
browser’s Title Bar
<html>
<head>
<title>…</title>
</head>
<body>
body elements
</body>
</html>
Creating Headings
The <h> tag
– Six levels of headings (n is a
value between 1 and 6)
– Goes between <body> and
</body> tags
– Most prominent <h1>…</h1>
– Least prominent <h6>...</h6>
<html>
<head>
<title>…</title>
</head>
<body>
<h1>…</h1>
<h4>…</h4>
</body>
</html>
HTML Paragraph Formatting
Whitespace is ignored in HTML
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Carriage Returns
Spaces (more than one)
Tabs
Use it in your HTML code to increase readability
In order to break up text use:
– Paragraph tag: <p>Text</p>
– Break tag: <br>
HTML Paragraph Formatting
Centering text
– Use <center> tag
• Example:
– <center>Text</center>
– Use ALIGN attribute with heading or paragraph tags
• Example:
– <p align=“center”>Text</p>
– <h3 align=“center”>Text</h3>
Colors
Two ways of defining colors in HTML
– Color Names
• May vary from browser to browser
– Color Numbering
• 216 safe colors
• www.usna.edu/Masters/Resources/colors.htm
Red
Green
Blue
FF F7 E3
Setting Defaults
<body> tag attributes
– Used within the <body> tag
– To set the back ground color, use bgcolor
• <body bgcolor = “blue”>
• <body bgcolor = “0000ff”>
– To set the default color for all text, use text
• <body text = “red”>
• <body text = “ff0000">
– To set the background as one image, use background
• <body background = “usnalogo.gif”>
These attributes are deprecated (still used, but being
phased out)
Setting Fonts
Use <font> tag with desired attribute(s)
Font Tag Attributes
– Size
• Seven sizes (1 - smallest, 7 - largest, 3 - default)
• <font size = “4”>This is some text</font>
– Color
• <font color = “blue”>This will be blue</font>
– Face
• <font face = “arial”>
• Use with caution – User must have font installed on their computer
This tag is deprecated (still used, but being phased out)
Syntactic-Based Styles
Specify how text should appear
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<b> bold
<i> italic
<u> underline
<tt> teletype (fixed-width font)
<sub> subscript
<sup> superscript
Used in pairs (e.g., <b>U.S. Naval Academy</b>)
Tables
Use <table> tag to help
organize information or
graphics
– Use <tr> tag to define a
row
• Use one or more <td>
within a row to assign
contents to a particular
column position in a
particular row
<table>
<tr>
<td>
information
</td>
<td>
information
</td>
</tr>
</table>
Including Images
Image Tag Attributes
– src - URL to retrieve image from
– alt - Text to be displayed when moused over (or when using a
text browser)
– height - expressed in pixels or percentage of browser window
– width - expressed in pixels or percentage of browser window
Example
<img src=“usnalogo.gif” alt=“Naval Academy” height=”50" width=”100">
Creating Hyperlinks
Anchor Tag
– Tag used to place hyperlinks in hypertext documents
– Browsers change hyperlink text color & underline
Three basic parts of a hyperlink
– Beginning and ending anchor tag pair <a> ... </a>
– href (hyperlink reference )attribute
• URL of page to be loaded when hyperlink is selected
– Text (or graphic) that appears on-screen as the hyperlink
Examples
– <a href=“http://www.usna.edu”>U.S. Naval Academy</a>
– <a href=“mailto:[email protected]”>E-mail me!</a>
Resources
Tutorials
– www.all-html.com, www.htmlgoodies.com
– www.ncsa.uiuc.edu/General/Internet/WWW/HTMLPrimerP1.html
– www.webmonkey.com
Free Clipart
– www.freegraphics.com
– www.clipart.com
Free Counters, Guest Books, Chat Rooms
– www.freecenter.com
– www.thefreesite.com
Summary
Computer Science is an exciting, rapidly changing
field
Computer Science professionals are always in high
demand
– Many jobs
– Top Salaries
The USNA Computer Science Department is a topnotch program which will prepare you for an exciting
future in today’s technology-driven world