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Wednesday, March 4, 2009

Ontology-Based Adaptive E-learning System Modeling in Semantic Learning Web

As information increases explosively, the diversity and heterogeneity
of knowledge in different domains make it difficult to represent and
share knowledge. Meanwhile, the adaptive learning pattern is favored
by more and more learners, and how to acquire the knowledge in need
from complex knowledge bases and construct personal knowledge system
has recently become a hot spot of research.

Semantic learning web, which combines semantic web and web-based
education technologies, shed lights on the development of modem
education, and provide learners more efficient and high-quality
intelligent services. This paper, which based on semantic learning
web, semantically described domain knowledge and user pattern using
Ontology technology, presented the architecture of ontology-based
adaptive e-learning system (OntoAES) , provided the platform for
knowledge acquiring and sharing, and also provided learners with
effective learning services based on personal knowledge spaces and

Firstly, various theory models of teaching and learning processes were
studied; the definition and description of learning behaviors in those
theory models were analyzed; based on different characteristics of the
learning behaviors, the features and requirements of the adaptive
e-learning process was studied in order to provide the theory
architecture and behavior model for the adaptive e-learning system;
how to present knowledge space was studied, domain knowledge model and
user knowledge space model were established.

Secondly, the features of domain knowledge was studied; as the
complexity and diversity of domain knowledge and the lack of ontology
engineering technology for domain experts make it difficult to develop
domain ontology, the method to establish ontology based on knowledge
engineering was proposed; the method to extract domain knowledge
concepts, define concepts hierarchical structure and construct the
relationship models were presented. The construction process to build
domain ontology was simplified.

Thirdly, computer science was choose as the research domain, based on
the domain knowledge space model, the knowledge taxonomy architecture
and concept sets were constructed, and domain knowledge ontology was
built. On the basis of E-learning standards, learning resources
description Ontology was established, which provided more semantics to
learning resources description model and more space to be expanded.

Fourthly, the user information model and user knowledge space model
were studied, the user model Ontology was built. The user information
sub-Ontology to describe user's basic information, the user preference
sub-Ontology to describe user's preference information, user
performance sub-Ontology to describe user's performance information
along with the user competency Ontology to describe user's learning
skills were established respectively. The semantic association among
user model ontology, domain knowledge ontology and learning resources
description Ontology was analyzed. A well-modeled basis was build for
the adaptive e-learning system.

Finally, the functional modules and system architecture of the
ontology-based adaptive e-learning system (OntoAES) were presented,
the correlation and application pattern between various Ontology and
system modules were studied. The adaptive e-learning steps and process
of the OntoAES were discussed. Based on analysis of user learning
behavior records, the analysis and definition of the potential
learning resource relation pattern based on users' use of log, the
relation model and user preference model were acquired through
information extraction and data mining technologies. Learning path
information in Domain knowledge and user preference information could
be refreshed; the model and method this paper presents were verified.

The main contributions are as follows:

1) Present the relation model of knowledge space, and method to build
domain knowledge Ontology based on knowledge engineering;
2) establish the Ontology of computer science domain and user model
Ontology, present the architecture of the Ontology-based adaptive
e-learning system;
3) Define the adaptive e-learning rules based on Ontology, build the
matching model between user preference ontology and study resource
description ontology, study resource relation model and preference
model based on data using.

This paper provides the basis and guidance for establishing the
ontology of the Education Semantic Web, and design and building of the
adaptive e-learning system. The future work includes the perfection of
the ontology and the function of the adaptive e-learning system, the
study of the matching model in ontology as well as the rules of
adaptive e-learning based on ontology, and to provide learners an
intelligent and efficient learning system.

Read More......

Using Flash Drives in the Music Industry

Flash drives are often viewed as useful portable devices that can
store and transfer high volumes of files to other devices. Due to
their low costs and high capacities, they are widely used by all
classes of computer users. These compact devices became so popular
that people are less aligned to buy CDs and DVDs unless they are
purely for backup purposes. The music industry has realised this as
well and several bands are ditching the CDs as well by creatively
releasing their latest albums on flash drives.

This can simply be achieved by copying the tracks at their highest
quality into the drive, complete with track information and the drive
is ready to go. This is beneficial to both the fans and the artists
themselves. Here are some reasons why the use of flash drives in the
music industry should be welcomed:

Reduced Piracy

Music artists and record labels have been fighting piracy long and
hard, yet they still suffer from their songs being pirated even before
they are released. This is because most people cannot see any benefits
of purchasing the audio CD unless they are collectors. With the album
released on a flash drive, fans can view the specialized flash drive
as a 'freebie' that is unlike any standard USB flash drive.

Better Marketing

A music store is filled with tons of albums that compete for selection
by using their album art as the front end. Now artists can go beyond
their creative album arts and add style and funky designs to their
flash drives to make them really stand out. Nobody will resist a
uniquely styled flash drive that even has the logo. Some interesting
concepts allow people to wear their flash drive albums around their
neck or wrist.

Easier Distribution

Mp3 players have quickly replaced walkmans and discmans since they
were first introduced rendering the audio CD virtually useless. These
players have a high enough capacity to store hundreds of albums and
transferring these CD tracks to mp3 players requires a little bit of
conversion work. Most albums distribute their albums in mp3 format so
they are ready for play in any portable media device.

All the Benefits of a Flash Drive

Standard audio CDs are read-only, but flash drives can be formatted to
make way for other files. These album owners can optionally move their
tracks to another location and put other things in making it work just
like a regular flash drive that was newly purchased.

Purchased CDs often get scratched even when they are handled well and
are dust magnets as they age. Albums on flash drives get all the
protection benefits of flash drives which makes them last longer. They
are easier to store as well due to their compact size.

Album-branded drives aren't that popular as of yet since a single USB
drive is nowhere near the cost of a blank CD. But they are becoming
cheaper to produce and it is expected for more albums to be released
on these.

Read More......

Tuesday, March 3, 2009

What is Going On - Microsoft Versus TomTom

As there is only very little news available on this topic, how is one
to interpret this information. This is my first impression.

Microsoft said on Wednesday that it is steering Netherlands-based
vehicle navigation systems firm TomTom to court (and with the
International Trade Commission) for infringing on the software giant's
patented technology. The information is released by Horacio Gutierrez,
deputy general counsel of intellectual property and licensing at
Microsoft. (source Google news).

A first impression: Goliath (Microsoft) fighting against David
(TomTom). Is TomTom using Microsoft for its navigation devices? No, it
uses the Linux OS. That is the first problem in not making friend with
Microsoft. So what are they using from Microsoft? Something about
"file management, the ability to run multiple applications..." is what
reads the news. But filemanagement is that proprietary to MS or
Multi-using, multi-tasking... Is Unix or Linux not offering much
better alternatives? As there is no more information on this topic, we
have to speculate.

Microsoft tried for over a year to settle this dispute by offering a
licence agreement, but TomTom didn't respond. "Why should we," they
must have thought as they are not using their software. Software
patents is an opaque area of rules and details of intellectual
property that only lawyers can handle. But attacking your competition
this way is a means to use your brand name as a mechanism to exercise
power over others.

"TomTom is a highly respected and important company," Gutierrez said.
"We remain open to quickly resolving this situation with them through
an IP licensing agreement." This means as much as: they are small and
fast growing and a treat to us. And we have the time with us where
protecting national industry is seen as an act of heroism these
critical days. Maybe it helps in court.

The good news for TomTom is the attention they get. Yes the Stock
quote is harmed by this sort of news, but apparently they are doing a
good job otherwise Microsoft would attack them.

Read More......

Tuesday, February 24, 2009

Nokia N96 And 3G Apple Iphone : Satisfying The Users Requirements Perfectly

In the last few years, we have seen extraordinary changes in the mobile industry. A massive increase of mobile devices has created a lot of confusion regarding selection of model. The elegant brands Nokia and Apple have seen a monumental growth in the development of their mobiles. Both are doing exceptionally well in the area of mobile phones and one can find very high quality features equipped in their phones. The Nokia N96 and Apple iPhone 3G are handsets are famous all over the world. It is very hard to tell which one is better than other but we can find features at which one model take edge from the other. From the following discussion you can find the areas that differentiate them.

The amazing imaging features of Apple iphone includes 2MP digital camera and the photo setting and photo editor features come with this handset in order to increase the quality of the captured images. This camera phone has a video player that supports H264, MPEG4 and AAC formats. The photos can be rotated and zoomed using the touchscreen.On the other hand, Nokia N96 has an astounding 5 MP camera with Carl Zeiss Optics Tessa lens. The camera setting feature of this mobile include flash, self timer, colour and other features. Its video recorder supports MPEG4 and video stabiliser allows high quality capturing of the moving images.

The messaging features of iPhone are not very satisfactory, as it includes only SMS, email and push email features. On the contrary, you will find various great messaging features in Nokia N96 like SMS, MMS, email, email with attachments, picture messaging, instant messaging and so on.In terms of memory and talktime features, the Apple iphone is simply amazing. It comes with built-in 8 GB memory and 16 GB flash memory. The various talktimes delivered by this gorgeous handset are 5 hour of 3G talktime, 10 hours of 2G talktime, 5 hours 3G Internet use, 7 Hours video playback time, 24 hours music playback time and 300 hours standby time.

As opposed to this, the N96 offers the users 16GB memory and one can expand the memory by using MicroSD card. Furthermore, the mobile comes with 128 MB RAM and 256 MB system memory. The gadget offer you 3 hours of talktime and 220 hours standby time.The connectivity technologies supported by iPhone include 3G HSDPA, Bluetooth, USB, EDGE and WiFi. The N96 also supports similar technologies like 3G HSDPA, Bluetooth with A2DP, USB, EDGE and WLAN Wi-Fi UPnP.

The sound features of both the gadgets are mind blowing. The 3G Apple iPhone has an iPod music player in which you can create your own playlists. One can also perform the touchscreen search on this gadget and you can also pause the playing song by pause feature.The Nokia N96 has a music player supporting MP3, AAC formats and this gadget also comes with Nokia Internet Radio, Stereo FM Radio with RDS and visual radio features. This handset supports MP3 and Polyphonic types of ringtones.So, one can see how difficult is to judge one handset from the other. They give you excellent features and these high quality mobile phones will surely satisfy all your requirements.

Read More......

Wednesday, February 18, 2009

Emerging Trend: Large Lcd Monitors For Surveillance And Security

Increasingly video-based surveillance and security systems are being widely adopted by both corporations and consumers primarily due to increasing need for surveillance in these turbulent times but also due to affordability of security systems, ease with which surveillance systems can be installed and value-add features such remote monitoring that address special surveillance needs. As a result video-based surveillance systems are increasingly appearing in public areas such as airport lounges, shopping centres, retail stores, colleges, universities, manufacturing facilities and corporate offices. These video surveillance systems can be CCTV or IP based. Consider the benefits that a video surveillance system provides and the broad adoption by the market is quite understandable. A surveillance and security system:
Helps deter employee theft and shoplifting theft,
Helps monitor & document performance in manufacturing or other facilities resulting in potential reduction in maintenance cost and/or employee productivity improvement,
May help reduce insurance cost and fraudulent liability claims, and
Can continuously document events so your entire business has greater protection.

Reasons for Large LCD Monitor Adoption: Within these surveillance systems packages, large LCDs monitors (>42”) are becoming the industry norm. The reasons being:
Size: Large screens allow for continuous and simultaneous monitoring of multiple camera video feeds on one screen with clarity. Smaller screens require that the images from the video feeds to rotate creating holes in the monitoring data.
24x7 Operations: Professional LCD monitors are meant for 24x7 “round the clock” operations with long life. CRT televisions or Plasma television each have their issues with round the clock operations such as static or flicker for CRT televisions. Also, the life of a CRT or Plasma TV is much shorter when operated in 24x7 operation mode as compared to an LCD monitor. CRT and Plasma televisions are built to be on for a few hours per day.
Picture Quality: Most large LCDs are high definition. High definition LCDs provide better picture resolution, better contrast ratio, high brightness, high colour reproduction and fast response time resulting in better picture clarity which is especially helpful when the camera is being zoomed in or multiple images are viewed simultaneously. High Definition LCD TV allows you to view minute details like number plates of a speeding car, face of a person etc. Further, the non glare feature of LCDs allows for easy viewing in ambient light or where there is background light being reflected on the screen. It is harder to reduce glare in CRT or plasma televisions. Most new LCDs have 176° viewing angle, making it easy for viewing. Check the viewing specifications to make sure meets your quality requirements.
Robustness: LCDs generate less heat than a CRT or Plasma television. The fan-less design for most large LCD monitors results in a closed box display with less noise. The fan-less design and the closed box display also results in less dust entering the system and provides for a more robust architecture.
Space: LCD monitors are flat panel displays requiring less space than normal CRT TVs. They can be wall mounted. The LCD monitor can be encapsulated in a fire retardant frame to protect the display
Better Video and Data Merger: Increasingly programs are being utilized to identify theft or issues in real time and data is being merged onto the video stream in real time. LCDs provide for better merging and viewing of data with video.
Remote Monitoring and Operation of Large LCD Screens: Alarms can be set if an LCD screen is switched off. Power and other controls can be monitored remotely. For example, an energy saving feature can be activated so that when there is no signal, a power save mode is activated to reduce the brightness of the LCD backlight.
Value-add Features: Value-add features such as touch screen zoom-in /zoom-out and image swap or other functions such as internet access can be easily found or added onto LCD monitors.

Purchase Consideration When Buying a Large LCD Monitor: Besides price there are a few items to consider when purchasing an LCD monitor.
Match LCD Monitor to Camera Capabilities: If you buy a monitor with lower resolution than the cameras installed then the camera capabilities will not come through. Ideally the monitor should be equal or better resolution than the camera. Also, if the cameras are black and white, then a black and white monitor can be used.
Input /Output Connectors on the Monitor: With the increasing use of PC and digital video devices, it is important to have both analog VGA and digital DVI input terminals to the monitor. Also, be sure that the monitor has BNC connectors for direct connection from a video feed to the display. BNC connectors support video looping, which provides output (loops back) to a centralized recording facility (DVR) or to other displays in a daisy-chain pattern. When scrolling through different images, this allows for seamless integration between pictures .
Picture Quality Features: Consider the resolution, contrast ratio, brightness, colour reproduction and response time to meet your surveillance need.
Value-add Features: Consider the value-adds that address your need. Such as, do you need remote monitoring, touch screen capability, or internet access?

Make the knowledgeable decision and your surveillance system can address your needs for many years.

Read More......

Wednesday, December 17, 2008

An Introduction to Inductive Ignition Systems

Inductive ignition systems have existed since 1908, developed by Charles Kettering who also developed the first practical engine driven generator.

The design has been improved over the years but the most significant recent development has been the introduction of Insulated Gate Bipolar Transistors (IGBT); these have allowed the design of extremely accurate, high spark energy inductive ignition systems.

A single operation is carried out by a transistor turning on the current to the ignition coils primary winding. This ‘charging' stores energy in the coils magnetic circuit. The current is then switched off. As the magnetic field begins to collapse the coil tries to resist the drop in current causing the voltage in the secondary winding to rise rapidly, this high voltage breaks down the air/fuel mixture in the spark gap allowing a spark to pass, causing ignition of the air/fuel mixture.

The most significant advantage of inductive ignition systems is that inductive coils are generally more efficient than capacitive discharge coils as they can provide longer spark duration that can ensure complete combustion, especially on lean burn and turbo charged engines. The ability to provide longer spark duration is because inductive coils only provide enough energy to cross the spark gap; the remaining energy from the ignition coil is used to maintain the spark. Capacitive discharge coils release almost all of their energy instantaneously, therefore considerably reducing the amount of energy available to maintain the spark.

With inductive ignition systems more energy can be delivered to the secondary winding of the coil than in a capacitive ignition system. In fact, with the same power supply current draw, up to five times more energy can be delivered to the secondary winding of an inductive ignition coil than to a capacitive discharge coil. Typically a capacitive discharge system will deliver a maximum of 10 millijoules of energy compared to an inductive ignition system delivering more like 50 millijoules of energy and potentially in excess of 100 millijoules. This large difference in supplied energies will mean an inductive system can provide spark duration of 2000 microseconds or more in a single spark, compared to 600 microseconds for a capacitive system.

With inductive ignition systems the time taken to charge the ignition coil is called the ‘Dwell'. This dwell can be increased or decreased for differing engine applications. If longer spark duration is required to improve combustion of lean mixtures or engines with large cylinders the dwell time is increased, inputting more energy into the primary coil. Dwell time is decreased when there is more than enough spark energy to combust the mixture, this decrease will reduce spark plug wear, therefore increase spark plug life.

The high energy and long, programmable spark durations are a considerable advantage since they provide better ignition of lean or non-homogenous air/fuel mixtures. In many cases engines that are unable to meet emission standards with capacitive discharge systems can be bought into compliance with electronic inductive ignition systems such as those manufactured by Gill Instruments.

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