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Threads is the Wall Magazine of Department of Computer Science and Engineering, Govt. College of Engineering, Kannur
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Department of Computer Science and Engineering
August 2012
Page No. : 2
DepartmentofComputerScienceandEngineering
August 2012
Ubuntu Linux 12.04 'Precise
Pangolin' Is Here at Last .
For PC users, Ubuntu 12.04 supports lap-
tops, desktops, and netbooks with a unified
look and feel based on an updated version of
the desktop shell called 'Unity,' which intro-
duces 'Head-Up Display' search capabilities,”
wrote Ubuntu Release Manager Kate Stew-
art in the official announcement. “Finding
and installing software using the Ubuntu
Software Center is now easier thanks to im-
provements in speed, search, and usabil-
ity.”As a Long Term Support (LTS) release,
Ubuntu 12.04 will be supported for a full five
years on both desktops and servers, making
it a particularly attractive choice for business
users.
Though Canonical's servers appeared to
be swamped by demand on Thursday morn-
ing, the free and open source operating sys-
tem is available for download from the Ub-
untu site. Users of Ubuntu 11.10 “Oneiric
Ocelot” will be offered an auto-
matic upgrade. For a quick tour of Ubuntu
Linux 12.04, check out the slideshow I put
together earlier this week.
Seven New Features in Ub-
untu 12.04 'Precise Pangolin'
Beta 1
The HUD Makes Finding Menu
Items Super Easy:
Have you ever been in a situation where you're using a program, and want to do something specific that you know is in the menus, but you just don't know where? The new HUD solves that problem. Just hit Alt,
and a search bar will pop up in the upper left-hand corner of your screen. From there you can type in what you're looking for, and it will return any menu items that match your
query. If you've ever used a Mac, it's almost exactly like the Spotlight bar you get under the "Help" menu of individual applications, and it is a lifesaver.
Miscellaneous Improvements in
the Unity Interface
Love it or hate it, Unity is here to stay, and
the newest version has a few tweaks that
make it a bit more appetizing to those of us
on the fence. At the top of the list is a new
Video lens in the Dash (remember lenses?),
which searches not only videos on your com-
puter but videos online. That means you no
longer need to head to Amazon, Vimeo, or
TED Talks in your browser to start searching
for videos—just hit the Super key, click on
the video lens, and start typing. Sadly, it
doesn't search all of YouTube yet, just You-
Tube Movies and YouTube Shows, but hope-
fully this will change or someone will create
an add-on in the future.
You'll also find that Nautilus now has a
pretty beefy right-click menu in the Unity
UBUNTU LINUX 12.04
LinuxCorner
Page No. : 3
DepartmentofComputerScienceandEngineering
August 2012
DepartmentofComputerScienceandEngineering
dock, which is nice, plus some nice color-
matching effects if you have a powerful
enough machine. The "Appearance" settings
pane also has a few Unity-specific prefer-
ences, like auto-hiding the launcher.
Touchpads With Built-In Buttons
Work a Tiny Bit Better
For a long time, Ubuntu has had trouble with
ClickPad devices, where the touchpad itself is
the mouse button (like those found on
MacBook laptops). In Precise, ClickPad de-
vices are now fully supported. Finally, you can
click the button, but still move the cursor
around with a second finger on the trackpad.
In previous versions of Ubuntu, it had trouble
recognizing the second finger. Unfortunately,
trackpad support still really isn't there. While
clicking and dragging mostly works, Canonical
seems to have completely ignored regular
mouse movement. If you have your thumb on
the bottom of the trackpad, you can't move
the mouse with a second finger. The whole
thing still feels unnatural and unfinished.
Rhythmbox Is the Default Music
Player Again
We really dug Banshee as the default music
player in Ubuntu, but with version 12.04
they've defaulted back to the stable, popular
Rhythmbox. The biggest change here is that
the Ubuntu One Music Store is once again
available in Rhythmbox, so Ubuntu One users
are the only ones really affected—everyone
else can continue using whatever music player
they want.
Ubuntu One has a Few More Op-
tions
Lastly, Ubuntu One users will also find that
the Ubuntu One client interface has changed
a bit, and is now more similar to its Windows
counterpart. You also have the option to
choose which folders you want synced to your
machine, which is nice.
LibreOffice 3.5 and Rhythmbox :Among the default applications in Ubuntu
12.04 are the newly updated LibreOffice
3.5 as well as Rhythmbox as the default music
player.
Better Language Support When users install new software through
the Ubuntu Software Center, the correspond-
ing language support packages--including
translations and spell check modules--are now
installed automatically as well, thus eliminat-
ing the need to open "Language Support" af-
ter installing new software.
A Fresh Kernel :Finally, upgrading from the second alpha re-
lease of Precise Pangolin, this new beta ver-
sion includes the 3.2.0-17.27 Ubuntu kernel,
which is based on version 3.2.6 of the up-
stream stable Linux kernel.
LinuxCorner
Page No. : 4
DepartmentofComputerScienceandEngineering
August 2012
TechnologyTrendz
SURFACE COMPUTERS A surface computer is a computer that in-
teracts with the user through the surface of an
ordinary object, rather than through a monitor
and keyboard. The category was created by Microsoft
with Surface(codenamed Milan), the surface
computer from Microsoft which was based
entirely on a Multi-Touch interface and using a
coffee-table like design, and was unveiled on
30 May 2007. Users can interact with the ma-
chine by touching or dragging their fingertips
and objects such as paintbrushes across the
screen, or by setting real-world items tagged
with special bar-code labels on top of it.
The Surface is a horizontal display on a table
-like form. Somewhat similar to the iPhone,
the Surface has a screen that can incorporate
multiple touches and thus uses them to navi-
gate multimedia content. Unlike the iPhone,
which uses fingers' electrical properties to de-
tect touch, the Surface utilizes a system of in-
frared cameras to detect input. Uploading digi-
tal files only requires each object (e.g. a Blue-
tooth-enabled digital camera) to be placed on
the Surface. People can physically move
around the picture across the screen with their
hands, or even shrink or enlarge them.
The Surface has a 2.0GHz Core 2 Duo proces-
sor, 2GB of memory, an off the shelf graphics
card, a scratch-proof spill-proof surface, a
DLP projector, and 5 infrared cameras as
mentioned above. However, the expensive
components required for the interface also
give the Surface a price tag of between
$12,500 to $15,000.
Microsoft Surface
Microsoft Surface is a planned series of tab-
let PCs designed and marketed by Microsoft.
The Surface will be available in two versions,
"Surface" and "Surface Pro". "Surface" will
run the Windows RT operating system and
use an ARM CPU. "Surface Pro" will run the
Windows 8 Pro operating system and use an
Intel CPU. The display is a 10.6-inch, 16:9
widescreen HD Display (Surface), or Full HD
Display (Surface Pro).The product was an-
nounced by Microsoft CEO Steve Ballmer at a
Los Angeles event on June 18, 2012, at Milk
Studios.
Microsoft Surface is a touch-based graphi-
cal user interface. Using specialized hardware
designed to replace the keyboard and mouse
used in typical computing applica-
tions,Surface enables a level of interaction
previously unattainable with conventional
hardware. The system is composed of a hori-
zontal touchscreen under a coffee table-like
surface, with cameras mounted below to de-
tect user interaction activities. All interface
components such as dialogs, mouse pointer,
and windows, are replaced with circles and
rectangles outlining "objects" that are ma-
nipulated via drag and drop. The "objects" in
question can be either virtual objects dis-
played on the screen, or physical objects
such as cellphones, digital cameras, and
PDA's placed on the screen. Physical objects
are automatically identified and connected
to the Surface computer upon their place-
Page No. : 5
DepartmentofComputerScienceandEngineering
August 2012
TechnologyTrendz
Specifications
The most interesting thing about Microsoft
Surface is that it works on off-the-shell parts.
This means that it uses the standard CPU, Core
2 Duo chips used in most laptops and is built on
Windows Vistas operating system; Microsoft
didn’t have to re engineer anything special for
the Surface. The specifications of the Surface
are:
Display Type: 30-inch Flat panel display
CPU: Core 2 Duo processor
Processor: 1 GHz processor.
Installed Memory: 2GB of RAM
Hard drive: Yes
Graphics Card: 256MB graphics card.
Projector: DLP light engine (like the one used in
rear-projection HDTV).
Cameras: Five cameras with infrared filters -
net resolution of 1280 x 960
Surface: Not touch-sensitive surface. When you
place or drag a finger, internal projector lights
screen from beneath.
Power Supply: Standard American 110–120V
power
Operating System: The custom software plat-
form running on Windows Vista
Network Connectivity: Wired Ethernet 10/100
and wireless 802.11 b/g and Bluetooth 2.0 con-
nectivity.
Dimensions: 22 inches high, 21 inches deep and
42 inches wide.
Weight: 150 pounds
Technology
Multi-touch Technology: Multi-touch is a key attribute of Microsoft Surface. Multi-touch is a human-computer interaction tech-nique and the hardware devices that imple-ment it. Multi-touch consists of a touch screen or touch tablet that recognizes multiple simul-taneous touch points and software to interpret simultaneous touches. This frequently includes the position and pressure or degree of each touch point independently, which allows ges-tures and interaction with multiple fingers or hands and can provide rich interaction
(including direct manipulation) through intui-tive gestures.
Digital Light Processing Technology:
Microsoft’s new tabletop Surface technology
moves optical technology forward by combin-
ing physical and virtual worlds. It can interact
with objects placed on top of it through touch
and vision. It enables people to directly inter-
act with the interface on the table top, drag-
ging and dropping virtual objects such as digi-
tal photos with their fingers. The Surface uses
8-bit,75-inch tags that the cameras under-
neath the table can visually recognize. The
tags would have patterns of dots that the
cameras could see and translate into the com-
puter. Hence, the system is able to tell one
object apart from another. It uses the same
digital light processing technology (DLP) that
is behind rear-projection TVs to project im-
ages from the bottom of the table to the top,
which is a translucent acrylic screen.
Infrared: Surface also features the ability
to recognize physical objects that have identi-
fication tags similar to bar codes. For instance,
this means that when a customer simply sets
a wine glass on the surface of a table, a res-
taurant could provide them with information
about the wine they’re ordering, pictures of
the vineyard it came from and suggested food
pairings tailored to that evening’s menu. Sur-
face features a touch interface, but it doesn't
use a touch screen. Instead, five separate
cameras are used to record motion on the ta-
ble's surface.
The CPU: Surface currently runs on a high-
end PC but uses mainly conventional compo-
nents. It's powered by a Core 2 Duo chip, 2GB
of RAM and a 256MB graphics card. Surface
runs on a standard Vista installation with a
layer of code on top that is specific to the pro-
ject; the underlying operating system has not
been modified in any way. Surface applica-
tions can be written in Windows Presentation
Foundation or XNA.
Page No. : 6
DepartmentofComputerScienceandEngineering
August 2012
DidYouKnow
BIRTH CENTENARY OF ALAN TURING
University and work on comput-
ability
Turing studied as an undergraduate at
King's College, Cambridge from 1931 to
1934. In 1935, he proved the central limit
theorem despite the fact that he had failed
to find out that it had already been proved
in 1922 by Jarl Waldemar Lindeberg.Turing
reformulated Kurt Gödel's 1931 results on
the limits of proof and computation, replac-
ing Gödel's universal arithmetic-based for-
mal language with the formal and simple
hypothetical devices that became known as
Turing machines. He proved that some such
machine would be capable of performing
any conceivable mathematical computation
if it were representable as an algorithm. He
went on to prove that it is not possible to
decide algorithmically, whether a given Tur-
ing machine will ever halt.
From September 1936 to July 1938 he
spent most of his time studying under
Church at the Institute for Advanced Study
in Princeton, New Jersey. He studied cryp-
tology and also built three of four stages of
an electro-mechanical binary multiplier. In
June 1938 he obtained his PhD from Prince-
ton University; his dissertation, Systems of
Logic Based on Ordinals, introduced the
concept of ordinal logic and the notion of
relative computing, where Turing machines
are augmented with so-called oracles, al-
lowing a study of problems that cannot be
solved by a Turing machine.
Back in Cambridge, he attended lec-tures by Ludwig Wittgenstein about the foundations of mathematics .. He also started to work part-time with the Govern-ment Code and Cypher School (GCCS).The
two argued and disagreed, with Turing defend-
ing formalism and Wittgenstein propounding his
viewthat mathematics does not discover any
absolute truths but rather invents them.
Cryptanalysis During the Second World War, Turing was a
leading participant in the breaking of German
ciphers at Bletchley Park.From September 1938,
Turing had been working part-time with the
Government Code and Cypher School (GCCS),
the British code breaking organisation. He con-
centrated on Cryptanalysis of the Enigma, with
Dilly Knox, a senior GCCS codebreaker. Soon af-
ter the July 1939 Warsaw meeting at which the
Polish Cipher Bureau had provided the British
and French with the details of the wiring of
Enigma rotors and their method of decrypting
Enigma messages, Turing and Knox started to
work on a less fragile approach to the problem.
The Polish method relied on an insecure indica-
tor procedure that the Germans were likely to
change, which they did in May 1940. Turing's
approach was more general, using crib-based
decryption for which he produced the initial
functional specification of the bombe.
On 4 September 1939, the day after the UK
declared war on Germany, Turing reported to
Bletchley Park, the wartime station of
GCCS.Specifying the bombe was the first of five
major cryptanalytical advances that Turing
made during the war.By using statistical tech-
niques to optimise the trial of different possibili-
ties in the code breaking process, Turing made
an innovative contribution to the subject. He
wrote two papers discussing mathematical ap-
proaches which were entitled Report on the ap-
plications of probability to cryptography and
Paper on statistics of repetitions, which were of
such value to GCCS and its successor GCHQ, that
they were not released to the UK National Ar-
Page No. : 7
DepartmentofComputerScienceandEngineering
August 2012
DidYouKnow
and its successor GCHQ, that they were not re-
leased to the UK National Archives until April
2012, shortly before the centenary of his birth.
Turing–Welchman bombe
Turing had specified an electromechanical
machine that could help break Enigma more
effectively than the Polish bomba kryptologic-
zna, from which its name was derived. The
bombe, with an enhancement suggested by
mathematician Gordon Welchman, became one
of the primary tools, and the major automated
one, used to attack Enigma-enciphered mes-
sages.The bombe searched for possible correct
settings used for an Enigma message (i.e. rotor
order, rotor settings and plugboard settings),
using a suitable crib: a fragment of probable
plaintext. For each possible setting of the rotors
(which had of the order of 1019 states, or 1022
for the four-rotor U-boat variant), the bombe
performed a chain of logical deductions based
on the crib, implemented electrically. The
bombe detected when a contradiction had oc-
curred, and ruled out that setting, moving on to
the next. Most of the possible settings would
cause contradictions and be discarded, leaving
only a few to be investigated in detail. The first
bombe was installed on 18 March 1940.
Hut 8 and Naval Enigma
In December 1939, Turing solved the es-
sential part of the naval indicator system, which
was more complex than the indicator systems
used by the other services. He also conceived of
the idea of Banburismus, a sequential statistical
technique to assist in breaking naval Enigma.
For this he invented a measure of weight of evi-
dence that he called the Ban. Banburismus
could rule out certain sequences of the Enigma
rotors, substantially reducing the time needed
to test settings on the bombes.Turing travelled
to the United States in November 1942 and
worked with U.S. Navy cryptanalysts on Naval
Enigma and bombe construction in Washing-
Labs with the development of secure speech
devices.
Turingery
In July 1942, Turing devised a technique
termed Turingery (or jokingly Turingismus)
for use against the Lorenz cipher messages
produced by the Germans' new Geheim-
schreiber (secret writer) machine. This was a
teleprinter rotor cipher attachment code-
named Tunny at Bletchley Park. Turingery
was a method of wheel-breaking, i.e. a pro-
cedure for working out the cam settings of
Tunny's wheels.
Secure speech device (Delilah)
Following his work at Bell Labs in the
US, Turing pursued the idea of electronic
enciphering of speech in the telephone sys-
tem, and in the latter part of the war, he
moved to work for the Secret Service's Radio
Security Service (later HMGCC) at Hanslope
Park. There he further developed his knowl-
edge of electronics with the assistance of
engineer Donald Bayley. Together they un-
dertook the design and construction of a
portable secure voice communications ma-
chine codenamed Delilah. It was intended
for different applications, lacking capability
for use with long-distance radio transmis-
sions, and in any case, Delilah was com-
pleted too late to be used during the war.
Though Turing demonstrated it to officials
by encrypting and decrypting a recording of
a Winston Churchill speech, Delilah was not
adopted for use.Turing also consulted with
Bell Labs on the development of SIGSALY, a
secure voice system that was used in the
later years of the war.
Page No. : 8
DepartmentofComputerScienceandEngineering
August 2012
Tips�Tricks
FunnyFunnyFunnyFunny Tricks
Some webpages use this behavior to create
some amazing and funny results. Here is a
list of few such keywords that have some
funny websites at the first position in
Google. To use these tricks, open Google's
homepage, type in the phrase and hit the
I'm feeling lucky button. To use the I'm
feeling lucky button, you have to disable
Google Instant.
1. Google Gravity
The force of gravity is non-existent in cyber
space. Google gravity makes you realize
how Google would have been if gravity had
been effective on the internet as well. Just
type Google gravity in the search bar and
press the I'm feeling lucky button. This will
take you to the Google gravity page which,
at first look, might appear to be the Google
homepage itself. Wait for a few seconds
and you will realize why this Chrome experi-
ment is called Google gravity. Although the
website lists it as a Chrome experiment, it
works on Mozilla Firefox as well, although it
does not work on IE8 and previous versions
of IE.
2. Who is the cutest?
Want to know who is the cutest person in
the world? Just use this phrase. This one
will definitely make you smile.
3. Google Sphere
Want to see images on Google dance in circular
motion? Google sphere is the phrase for that.
This phrase will take you to the Google
sphere Chrome experiment. Google sphere is a
modified version of Image search that adds a bit
of fun to your regular search. This Chrome ex-
periment, just like the previous one, works on
Chrome, Firefox and IE9.
4. Enable Pirate language in Google
Google too has their own pirate version to com-
pete with that of Facebook's. Just use
the Google Pirate phrase or directly head over
to Google Pirate.
5. Epic Google
Epic Google will take you to a growing version of
Google that will continue to increase in size until
it becomes too large to read.
6. Annoying Google
Want to get annoyed while searching on
Google? This one is for you. This phrase will take
you to a Google search homepage with each
word having alternate capital and small letters
making everything a bit too hard to read.
7. Google Rainbow
This phrase will take you to a Google search
homepage in which each element changes its
color rapidly to create the rainbow effect. The
search result page obtained for queries is very
annoying too as it contains a very loud color
combination of red, blue and green.
Page No. : 9
DepartmentofComputerScienceandEngineering
August 2012
Tips�Tricks
8. 2204355
Are you already familiar with the age old inter-
net prank called rick-rolling and want to dis-
cover something new? Chicken rolling is for
you. Try this new way of trapping unsuspect-
ing internet users by typing the code 2204355
in the Google search box and hitting the "Lucky
button."
9. Zerg Rush
Search Google for Zerg Rush and you will see
the O's of Google attacking the search results
page. They will attacking every result one by
one. There is a health bar which indicates how
injured a search result is. You can also kill these
O's by clicking on them. They also have health
bars which indicates their health. You get points
on the basis of how many O's you kill. The aim
of this game is to beat as many O's as possible.
10. Google Magic
Do you like magic? Here's a trick to impress
your friends with. Type in Google Magicin the
Google search box and hit the I'm feeling lucky
button and you will be taken to a special
Google homepage. On this page, cover the two
O's in the Google Logo with your hand and click
anywhere on the page. Wait for sometime
(5 seconds). You can say some
magic words to add effect.
Remove your hand and you will be surprised
to see that the two O's have disappeared.
Again cover the two O's and click anywhere
on the page. Again wait for 5 seconds and
the O's will magically reappear. A third click
however will take you to the actual Google
homepage.
11. Google Pacman
Not a Google bomb but an immensely popu-
lar doodle which Google used on its home-
page on the 30th anniversary of Pacman, the
arcade game in May 2010. Just type Google
Pacman in the search box, hit the I'm feeling
lucky button and you will be taken to
the Google Pacman page. You can use your
arrow keys to start playing the game. To play
in 2 player mode, hit the Insert Coin button.
W, S, A and D keys will control the second
player.