Saturday, September 29, 2012

Machine Translation

The term machine translation (MT) is used in the sense of translation of one language to another. The ideal aim of machine translation systems is to produce the best possible translation without human assistance. Basically every machine translation system requires programs for translation and automated dictionaries and grammars to support translation.
The translation quality of the machine translation systems can be improved by pre-editing the input. Pre-editing means adjusting the input by marking prefixes, suffixes, clause boundaries, etc. Translation quality can also be improved by controlling the vocabulary. The output of the machine translation should be post-edited to make it perfect. Post-editing is required especially for health related information.


TYPES OF MACHINE TRANSLATION SYSTEMS
Machine translation systems that produce translations between only two particular languages are called bilingual systems and those that produce translations for any given pair of languages are called multilingual systems. Multilingual systems may be either uni-directional or bi-directional. Multilingual systems are preferred to be bi-directional and bi-lingual as they have ability to translate from any given language to any other given language and vice versa.
Machine Translation Pyramid


DIRECT MACHINE TRANSLATION APPROACH
Direct translation approach is the oldest and less popular approach. Machine translation systems that use this approach are capable of translating a language, called source language (SL) directly to another language, called target language (TL). The analysis of SL texts is oriented to only one TL. Direct translation systems are basically bilingual and uni-directional. Direct translation approach needs only a little syntactic and semantic analysis. SL analysis is oriented specifically to the production of representations appropriate for one particular TL.


INTERLINGUA APPROACH
Interlingua approach intends to translate SL texts to that of more than one language. Translation is from SL to an intermediate form called Interlingua (IL) and then from IL to TL. Interlingua may be artificial one or auxiliary language like Esperanto with universal vocabulary. Interlingua requires complete resolution of all ambiguities in the SL text.


TRANSFER APPROACH
Unlike interlingua approach, transfer approach has three stages involved. In the first stage, SL texts are converted into abstract SL-oriented representations. In the second stage, SL-oriented representations are converted into equivalent TL-oriented representations. Final texts are generated in the third stage. In transfer approach complete resolution of ambiguities of SL text is not required, but only the ambiguities inherent in the language itself are tackled. Three types of dictionaries are required: SL dictionaries, TL dictionaries and a bilingual transfer dictionary. Transfer systems have separate grammars for SL analysis, TL analysis and for the transformation of SL structures into equivalent TL forms.


EMPIRICAL MACHINE TRANSLATION APPROACH
Empirical approach is the emerging one that uses large amount of raw data in the form of parallel corpora. The raw data consists of texts and their translations. Example-based MT, analogy-based MT, memory-based MT, and case-based MT are the techniques that use empirical approach. Basically all these techniques use a corpus or database of translated examples. Statistical machine translation is corpus based but slightly different in the sense that it depends on statistical modelling of the word order of the target language and of source-target word equivalences. Statistical machine translationautomatically learns lexical and structural preferences from corpora. Statistical models offer good solution to ambiguity problem. They are robust and work well even if there are errors and the presence of new data. IBM researchers pioneered the first statistical approach to machine translation in 1980’s. IBM group relies on the source-channel approach, a framework for combining a word-based translation model and a language model. The translation model ensures that the machine translation system produces target hypothesis corresponding to the source sentence. The language model ensures the grammtically correct output.





Friday, September 28, 2012

Virtual Laser Keyboard

Abstract

Most of us with personal computers use a keyboard to compose e-mails, type out word processing documents, visit Web sites and perform searches. On a typical cell phone with a three-by-four numeric keypad, we often have to punch through each key several times to get one word on the screen. Miniature keyboards on smart phones and PDA’s, however, attempt to solve that problem by giving users a complete QWERTY setup, but People with bigger fingers may find it too small to type. To make up for this, some manufactures have developed special virtual laser keyboards to accompany handheld devices. Instead of having to poke lightly around your phone's keyboard, a virtual laser keyboard connects to the phone and projects a full-sized virtual keyboard onto any flat surface.
 



The keyboard projects ruby red laser through a holographic prism that contains image of the two dimensional keyboard. The single laser beam is diffused by a hologram into outlines that make up a keyboard focused at the horizontal surface below the unit. In addition, at the very base of the unit an IR (infra-red - light invisible to human eye same as used in remote controls) illuminates the plane a few millimeters above the projected laser keyboard. In the middle of the base there is a small "web cam" that has a filter to see IR light. This very camera is able to detect if any object does obstruct IR light and is able to derive the coordinates and calculate what key is being triggered.


Portability

  • One of the most important advantages of virtual laser keyboard technology is the relative ease by which these devices may accompany smaller hardware. As miniaturization takes over the mobile computing industry, the primary sacrifice is quality data input. Smartphones, PDAs and even some computers are too small for many people to reliably operate. Often, the type of activity on these devices is limited by the size of their keys. Some users eventually get used to the size, but the larger buttons of a regular keyboard will always make certain tasks easier. The virtual laser keyboard is projected by a small device that easily travels with this other technology. When connected, it allows a full-size keyboard to integrate with the device for all data input. While it would be otherwise impractical to transport a separate, conventional hardware keyboard, these virtual devices add this crucial functionality without compromising the small size of this new technology.

Appearance


While not necessarily a practical consideration, it is important to note the significant role that style plays in the development of portable technology. As noted in the Pittsburgh Business Times in June 2002, the visual appeal of mobile technology is as important in product success as actual functionality. Unlike most forms of technology that have come before them, smartphones and similar devices are enjoying trends similar to that of fashion, and many consumers accessorize their lifestyles with this in mind. Virtual laser keyboards fit well into this mindset because their function often draws much attention. As the ultimate attention-grabbing example of their functionality, some virtual laser keyboards can project the keyboard image into the air to allow control without a flat surface. Rarely are these devices mentioned in the media without reference to their visual appeal.

Maintenance


Unlike conventional hardware keyboards, virtual laser keyboards have no moving parts, and the bulk of their functionality requires no actual contact with the device. Whereas conventional hardware is prone to damage by spills, drops and other malfunctions, virtual laser keyboards are easy to maintain. Manufacturers often market these devices as "damage free," and this is an important advantage in any piece of portable hardware that undergoes extensive use.

Read more: The Advantages of a Virtual Laser Keyboard | eHow.com http://www.ehow.com/list_5772511_advantages-virtual-laser-keyboard.html#ixzz2AzXNcOab



Virtual Laser Keyboard Basics


There are actually two projections onto the flat surface in front of the projector. The projection you can see is the red holographic laser projection. A few millimeters above the red projection is an invisible infrared (IR) projection. When you press a key, the IR projection above the key is bounced back into the projector that interprets from the angle which key was pressed. The technology was invented at IBM and patented by them in 1992. The standard projector connects to a computer either by Bluetooth (at 2.4 GHz) or through a standard USB connector.

The Projection Module


The virtual keyboard system consists of three modules: The projector module, the illumination module and the sensor module. The projection module just projects the red keyboard (using a red diode laser) onto a flat surface. This projection is only a reference for the typist. In a fixed environment you could draw the projected keyboard and then use the drawing to type on---the holographic projection is only a reference. The projection is 95 mm by 295 mm and starts 60 mm in front of the projector
.
 

The Illumination Module


The illumination module projects parallel beams of invisible IR signals---similar to the signals produced by TV remote controls---that are a few millimeters above the red keyboard hologram. When the typist hits a red key he breaks the IR beams and reflects some of the beam back to the projector.

The Sensory Module


The sensory module of the projector contains a CMOS camera and a microprocessor to turn the returned signals into keystrokes. It is like radar except it is using IR over a distance that is less than a meter. The sensory module transfers the keystroke codes to the computer via Bluetooth or over a USB cable.

Virtual Laser Keyboard Adventages


There are some advantages to virtual keyboards that only appeared after the process was developed. For example, typing on a flat surface and just touching the keys---instead of depressing them---reduces the instances of carpal tunnel syndrome. It also is more hygienic as the computer keyboard is one of the dirtiest places in the home---especially in terms of E. coli, which carries a lot of human diseases. One of the latest versions of the virtual keyboards (called the P-ISM) is the size of a fountain pen that you can carry in a shirt pocket. When you lay the pen on the table, it projects a virtual keyboard on the table and a computer screen on the wall behind the table. It is a complete computer that you carry in your shirt pocket---and the pen also writes.

Read more: Virtual Laser Keyboard Characteristics | eHow.com http://www.ehow.com/list_7434893_virtual-laser-keyboard-characteristics.html#ixzz2AzXtKK53


The Disadvantages of Virtual Keyboards

The Disadvantages of Virtual Keyboards thumbnail
Even laser-projected virtual keyboards can have disadvantages.
Virtual keyboards are available for on-screen typing or as a laser projection on a table or flat surface. A virtual keyboard allows users to type on their device without a bulky physical keyboard, which makes computing easier to manage while away from the office or home. The capabilities of the virtual keyboard are perfect for those communicating on the go.





Tactile Feel

  • One benefit of a physical keyboard is the ability to feel the keys pushing down. Although this is not necessary, it does help some users determine when a key is struck with an appropriate amount of force. The virtual keyboard does not provide the same tactile feel and can take some adjustment for those composing letters, documents or chatting online.

Space

  • On a device with enough screen space to accommodate a full size keyboard, it can be difficult to see the document being typed on the screen. A full-size QWERTY keyboard uses a large amount of the screen space to accommodate two hands while typing. This limits the ability to proofread a document or letter while typing. Only a fraction of the letter or document will be visible above the virtual keyboard.

Dirty Screens

  • While a physical keyboard can become dirty with crumbs, dust and debris, the screen usually remains clean. When using a virtual keyboard and touch-screen technology, the screen will inevitably become smudged and dirty. Over time, the device's screen can become difficult to see and read.

Ergonomics

  • Using a virtual keyboard on a larger tablet style device can cause ergonomic issues for the user. The device must be propped at an angle to keep wrists in the proper position for comfortable typing. The user must also look directly down on the screen while typing and this can lead to neck injury or neck fatigue if typing for a long period.


Read more: The Disadvantages of Virtual Keyboards | eHow.com http://www.ehow.com/list_7441349_disadvantages-virtual-keyboards.html#ixzz2AzYRcIWJ


Features:
Works in BlueTooth HID or SPP mode. Connects to PDAs, Smartphones and Computers using Bluetooth.
Projects a full size keyboard onto any flat surface.
Allows the convenience of regular keyboard typing in a tiny form factor.
Rechargeable battery lasts for 2 hours of continuous typing.
Tiny size only 3.5 inches high.
Compatible with PalmOS 5, PocketPC 2003, Windows Smartphone, Symbian OS, and Windows 2000/XP.

Keystroke Sensor:
Ambient illumination: Works under all standard indoor illuminations up to 600 lux.
Detection: rate Up to 400 characters per minute.
Detection algorithm: Multiple keystroke support.
Effective keystroke: Approximately 2mm. GDGVKW
Operating surface: Any firm flat surface with no protrusions greater than 1mm.

Bluetooth:
Bluetooth Spec: Bluetooth v1.1 class 2.
Bluetooth Profile Supported: HID and SPP.
Range of Frequency: 2.4GHz Spectrum.
Transmission range: 9m.
Number of supported passkeys: 5.

Electrical:
Power source: Integrated, 3.6V rechargeable lithium-ion battery.
Battery capacity > 120 minutes continuous typing.
Charge Method: Included 100-240V AC Wall Adapter.

Compatibility:
Link to the list of supported devices: Compatibility List Support for PalmOS 5, PocketPC 2003, Windows Smartphone, Symbian OS, and Windows 2000/XP (Mac OSX will work but drivers are not provided. See the bottom of this page for details.) Look below for a list of specific compatible devices. Please note your device may still work properly if not on this list as long as it supports one of the OS listed above.

Keystroke Sensor:
Ambient illumination: Works under all standard indoor illuminations up to 600 lux.
Detection: rate Up to 400 characters per minute.
Detection algorithm: Multiple keystroke support.
Effective keystroke: Approximately 2mm. GDGVKW
Operating surface: Any firm flat surface with no protrusions greater than 1mm.

Bluetooth:
Bluetooth Spec: Bluetooth v1.1 class 2.
Bluetooth Profile Supported: HID and SPP.
Range of Frequency: 2.4GHz Spectrum.
Transmission range: 9m.
Number of supported passkeys: 5.

Electrical:
Power source: Integrated, 3.6V rechargeable lithium-ion battery.
Battery capacity > 120 minutes continuous typing.
Charge Method: Included 100-240V AC Wall Adapter.

Compatibility:
Link to the list of supported devices: Compatibility List Support for PalmOS 5, PocketPC 2003, Windows Smartphone, Symbian OS, and Windows 2000/XP (Mac OSX will work but drivers are not provided. See the bottom of this page for details.) Look below for a list of specific compatible devices. Please note your device may still work properly if not on this list as long as it supports one of the OS listed above.

 
VKB (Virtual Keyboards) enhances and enables the communications, computing and entertainment experience through innovative virtual interface technology. The Virtual Keyboard uses light to project a full-sized computer keyboard onto almost any surface. Used with Smart Phones and PDA's, the VKB provides a practical way to do email, word processing and spreadsheet tasks, allowing the user to leave the laptop computer at home. VKB observes the user's finger movements to interpret and record keystrokes. Since the virtual keyboard is an image projected in light, it completely disappears when not in use.

VKB (Virtual Keyboards) has developed an autonomous virtual Keyboard unit using proprietary electro-optic technology and has applied for patent protection. The initial products provide superior data input solutions that significantly enhance the usefulness of many wireless communications and computing devices.


The proprietary IR based detection method that VKB has developed provides accurate and reliable detection of user interaction, such as typing or cursor control functions (e.g. mouse or touch-pad controls).VKB has resolved all the technological hurdles required to make a practical user interface. The virtual Keyboard unit is small size, efficient in power consumption, operates with high accuracy and is extremely easy to use.




Technology

How does it work?




Step 1: Template creation (Projection Module)
A template of the desired interface is projected onto the adjacent interface surface. The template is produced by illuminating a specially designed, highly efficient holographic optical element with a red diode laser.
Note: the template serves only as a reference for the user and is not involved in the detection process. In a fixed environment, the template can just as easily be printed onto the interface surface.

Step 2: Reference plane illumination (Micro-illumination ModuleTM)
An infra-red plane of light is generated just above, and parallel to, the interface surface. This light is invisible to the user and hovers a few millimeters above the surface.
When the user touches a key position on the interface surface light is reflected from this plane in the vicinity of the key and directed towards the sensor module.

Step 3: Map reflection coordinates (Sensor Module)
Reflected light from user interactions with the interface surface is passed through an infra-red filter and imaged on to a CMOS image sensor in the sensor module.
Custom hardware embedded in the sensor chip (the Virtual Interface Processing CoreTM) then makes a real-time determination of the location of the reflected light.
The processing core can track multiple reflection events simultaneously and can thus support both multiple keystrokes and overlapping cursor control inputs.


Compatibility


VKB Environments:

  • Personal digital assistants
  • Cellular telephones
  • Space saving computers
  • Tablet PCs
  • Laptops
  • Industrial environments
  • Clean rooms
  • Sterile and medical environments
  • Test Equipment 
  • Transport (Air, Rail, Automotive)



    Only $169.99
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