Transcript Client
Important skills for
Computer Based
Researching
Peter Szluka, Attila Skulteti
2012. 09.17
Network Communication
Network: A group of computers connected
through a communication channel. (Internet)
Two
types of computers: server and client
Client-Server connection
Dedicated computer,answers the requests: server
For example: Web servers, database servers etc..
The one that makes the requests: client
Typically home, or end-user computers
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Network Communication
How computers find each other?
IP address: ID of the computers connected
to the internet.
Format: x.x.x.x, x={0-255}
Domain name: Like IP address, but easy
to memorize. Translation: DNS servers
eg.: www.lib.sote.hu=193.6.208.49
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Network Communication
Limitations of IP address: (IPv4)
4 000 000 000 unique address (232)
IP exhaustion soon
Solution: Network Address Translation
around
Real Solution : IPv6 (Internet Protocol
version 6)
128 bit adresses – much much more
possible address and better structure
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Network Communication
Client No. 1
Computer (DSL, Dialup)
195.56.231.109
Server
IP: 193.6.208.49
Domain: www.lib.sote.hu
NAT
Computer 1:
Local (inner) IP: 10.2.1.15
Real (outer) IP: 193.6.208.42
(Authentication)
NAT: Network address translation
Proxy server 1
(eg. DSL Router)
193.6.208.42
Client
Computer 1
10.2.1.15
Client
Computer 2
10.2.1.18
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Network Communication
Database ‘login’ types, authentication
IP identification
Automatic
method, no Username or Password
needed.
Only for fixed IP-s
Password authentication
From
any IP (You can use it at home)
Not automated (Number of problems increased by
number of databases, forgotten, stolen password)
Combined (IP and Password)
Rarely
used. Data acquisition, login statistics (eg.
EISZ)
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URL format
Format:
protocol://servername.domain.country
HTTP:// Hyper Text Transfer Protocol
For
HTML pages, Default value of the browsers
FTP:// File Trasfer Protocol
Downloading
files
Server name: In most cases WWW (World
Wide Web) Can be different: http://images.md
WWW is NOT need in every URL!
Domain: Usually shows the structure of the
institute
Eg.: lib.sote.hu (.hu: Hungary, .sote:Semmelweis
University, .lib:Library)
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Word processors
Microsoft Word (2003, 2007, 2010 etc..)
Part
of MS Office, widespread
Open Office
Free,
WordPad
You
similar to MS Office, compatibility problems.
can use it in the library. „Word lite”
Notepad (Plain text)
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Document formats
DOC and DOCX (MS Word)
Compatibility
problems
Rich Text (.rtf)
Recommended
to use with Wordpad
Plain Text (.txt)
Just
characters, formatting is not available
(Bold fonts, font type, etc.)
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E-journals, Article formats
PDF Full-text
PDF (Portable Document Format, Adobe)
Reprint
format (Like photocopies)
File size can be large (depending format and page
number)
Easy to save (if it is not copy protected)
Not easy to „reuse” the article (small Pictures)
Adobe Reader must be installed to view articles
Reading on small displays is problematic.
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E-journals, Article formats
HTML Full-text
HTML (Hyper Text Markup Language)
Showed
by your Internet Browser
Easy to read
Problems with printing
Problems with saving
Good for „Reusing” pictures, tables, etc.
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Link Resolver systems
Automated searches with the bibliographic data
of the results, when you search in a database
(like Medline)
Full text link appears in every record in the result
list. (If there is a full text available)
Fault possibility: Dynamic full-text databases. (If
you really need the article and full-text link does
not appears, in some cases you can find it in the
e-journals database at www.lib.sote.hu)
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Base Logic operators – Set theory
Set
Union
Boole Algebra
OR
Section
AND
Complement NOT
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Using the clipboard
A storage tool, wich allows to save, and
reuse data temporarily (text, images, etc.)
Always stores the last saved data. (some
programs, like Office can store more data
at once)
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Using the clipboard
Copy-Paste:
Ctrl-C:
puts the selected data into the
clipboard
Ctrl-V: copy the data from the clipboard
Printscreen
PrtScr:
the picture of the whole desktop
appears on the clipboard as an image
Alt+PrtScr: Only the selected window’s image
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Thank you for your attention!
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