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Tuesday, May 8, 2007
IMPORTANT
How Cloning Works
How Cloning Works
(Collected)
On January 8, 2001, scientists at Advanced Cell Technology, Inc., announced the birth of the first clone of an endangered animal, a baby bull gaur (a large wild ox from India and southeast Asia) named Noah. Although Noah died of an infection unrelated to the procedure, the experiment demonstrated that it is possible to save endangered species through cloning.
Cloning is the process of making a genetically identical organism through nonsexual means. It has been used for many years to produce plants (even growing a plant from a cutting is a type of cloning). Animal cloning has been the subject of scientific experiments for years, but garnered little attention until the birth of the first cloned mammal in 1997, a sheep named Dolly. Since Dolly, several scientists have cloned other animals, including cows and mice. The recent success in cloning animals has sparked fierce debates among scientists, politicians and the general public about the use and morality of cloning plants, animals and possibly humans.
In this article, we will examine how cloning works and look at possible uses of this technology.
Cloning is the process of making a genetically identical organism through nonsexual means. It has been used for many years to produce plants (even growing a plant from a cutting is a type of cloning). Animal cloning has been the subject of scientific experiments for years, but garnered little attention until the birth of the first cloned mammal in 1997, a sheep named Dolly. Since Dolly, several scientists have cloned other animals, including cows and mice. The recent success in cloning animals has sparked fierce debates among scientists, politicians and the general public about the use and morality of cloning plants, animals and possibly humans.
In this article, we will examine how cloning works and look at possible uses of this technology.
Dolly
In 1997, cloning was revolutionized when Ian Wilmut and his colleagues at the Roslin Institute in Edinburgh, Scotland, successfully cloned a sheep named Dolly. Dolly was the first cloned mammal.
Wilmut and his colleagues transplanted a nucleus from a mammary gland cell of a Finn Dorsett sheep into the enucleated egg of a Scottish blackface ewe. The nucleus-egg combination was stimulated with electricity to fuse the two and to stimulate cell division. The new cell divided and was placed in the uterus of a blackface ewe to develop. Dolly was born months later. Dolly was shown to be genetically identical to the Finn Dorsett mammary cells and not to the blackface ewe, which clearly demonstrated that she was a successful clone (it took 276 attempts before the experiment was successful). Dolly has since grown and reproduced several offspring of her own through normal sexual means. Therefore, Dolly is a viable, healthy clone.
Since Dolly, several university laboratories and companies have used various modifications of the nuclear transfer technique to produce cloned mammals, including cows, pigs, monkeys, mice and Noah.
Since Dolly, several university laboratories and companies have used various modifications of the nuclear transfer technique to produce cloned mammals, including cows, pigs, monkeys, mice and Noah.
How Robots Work
How Robots Work
(Collected)
On the most basic level, human beings are made up of five major components:
A body structure
A muscle system to move the body structure
A sensory system that receives information about the body and the surrounding environment
A power source to activate the muscles and sensors
A brain system that processes sensory information and tells the muscles what to do
Of course, we also have some intangible attributes, such as intelligence and morality, but on the sheer physical level, the list above about covers it.
A robot is made up of the very same components. A typical robot has a movable physical structure, a motor of some sort, a sensor system, a power supply and a computer "brain" that controls all of these elements. Essentially, robots are man-made versions of animal life -- they are machines that replicate human and animal behavior.
In this article, we'll explore the basic concept of robotics and find out how robots do what they do.
A body structure
A muscle system to move the body structure
A sensory system that receives information about the body and the surrounding environment
A power source to activate the muscles and sensors
A brain system that processes sensory information and tells the muscles what to do
Of course, we also have some intangible attributes, such as intelligence and morality, but on the sheer physical level, the list above about covers it.
A robot is made up of the very same components. A typical robot has a movable physical structure, a motor of some sort, a sensor system, a power supply and a computer "brain" that controls all of these elements. Essentially, robots are man-made versions of animal life -- they are machines that replicate human and animal behavior.
In this article, we'll explore the basic concept of robotics and find out how robots do what they do.
Robot Basics
The vast majority of robots do have several qualities in common. First of all, almost all robots have a movable body. Some only have motorized wheels, and others have dozens of movable segments, typically made of metal or plastic. Like the bones in your body, the individual segments are connected together with joints.
The vast majority of robots do have several qualities in common. First of all, almost all robots have a movable body. Some only have motorized wheels, and others have dozens of movable segments, typically made of metal or plastic. Like the bones in your body, the individual segments are connected together with joints.
Robots spin wheels and pivot jointed segments with some sort of actuator. Some robots use electric motorsand solenoids as actuators; some use a hydraulic system; and some use a pneumatic system (a system driven by compressed gases). Robots may use all these actuator types.
A robot needs a power source to drive these actuators. Most robots either have a battery or they plug into the wall. Hydraulic robots also need a pump to pressurize the hydraulic fluid, and pneumatic robots need an air compressor or compressed air tanks.
The actuators are all wired to an electrical circuit. The circuit powers electrical motors and solenoids directly, and it activates the hydraulic system by manipulating electrical valves. The valves determine the pressurized fluid's path through the machine. To move a hydraulic leg, for example, the robot's controller would open the valve leading from the fluid pump to a piston cylinder attached to that leg. The pressurized fluid would extend the piston, swiveling the leg forward. Typically, in order to move their segments in two directions, robots use pistons that can push both ways.
The robot's computer controls everything attached to the circuit. To move the robot, the computer switches on all the necessary motors and valves. Most robots are reprogrammable -- to change the robot's behavior, you simply write a new program to its computer.
A robot needs a power source to drive these actuators. Most robots either have a battery or they plug into the wall. Hydraulic robots also need a pump to pressurize the hydraulic fluid, and pneumatic robots need an air compressor or compressed air tanks.
The actuators are all wired to an electrical circuit. The circuit powers electrical motors and solenoids directly, and it activates the hydraulic system by manipulating electrical valves. The valves determine the pressurized fluid's path through the machine. To move a hydraulic leg, for example, the robot's controller would open the valve leading from the fluid pump to a piston cylinder attached to that leg. The pressurized fluid would extend the piston, swiveling the leg forward. Typically, in order to move their segments in two directions, robots use pistons that can push both ways.
The robot's computer controls everything attached to the circuit. To move the robot, the computer switches on all the necessary motors and valves. Most robots are reprogrammable -- to change the robot's behavior, you simply write a new program to its computer.
Not all robots have sensory systems, and few have the ability to see, hear, smell or taste. The most common robotic sense is the sense of movement -- the robot's ability to monitor its own motion. A standard design uses slotted wheels attached to the robot's joints. An LEDon one side of the wheel shines a beam of light through the slots to a light sensor on the other side of the wheel. When the robot moves a particular joint, the slotted wheel turns. The slots break the light beam as the wheel spins. The light sensor reads the pattern of the flashing light and transmits the data to the computer. The computer can tell exactly how far the joint has swiveled based on this pattern. This is the same basic system used in computer mice.
These are the basic nuts and bolts of robotics. Roboticists can combine these elements in an infinite number of ways to create robots of unlimited complexity. In the next section, we'll look at one of the most popular designs, the robotic arm.
These are the basic nuts and bolts of robotics. Roboticists can combine these elements in an infinite number of ways to create robots of unlimited complexity. In the next section, we'll look at one of the most popular designs, the robotic arm.
How E-learning Works
How E-learning Works (Collected)
What is E-learning?
E-learning is to classroom learning as cell phones are to a pay phone at the bus station.
Well, at least it is in some ways. For instance, e-learning allows you to learn anywhere and usually at any time, as long as you have a properly configured computer. Cell phones allow you to communicate any time and usually anywhere, as long as you have a properly configured phone.
E-learning can be CD-ROM-based, Network-based, Intranet-based or Internet-based. It can include text, video, audio, animation and virtual environments. It can be a very rich learning experience that can even surpass the level of training you might experience in a crowded classroom. It is self-paced, hands-on learning.
The quality of the electronic-based training, as in every form of training, is in its content and its delivery. E-learning can suffer from many of the same pitfalls as classroom training, such as boring slides, monotonous speech, and little opportunity for interaction. The beauty of e-learning, however, is that new software allows the creation of very effective learning environments that can engulf you in the material. We'll use software from Trainersoft as an example to show you how the process works.
Levels of e-learningE-learning falls into four categories, from the very basic to the very advanced. The categories are:
Knowledge databases -- While not necessarily seen as actual training, these databases are the most basic form of e-learning. You've probably seen knowledge databases on software sites offering indexed explanations and guidance for software questions, along with step-by-step instructions for performing specific tasks. These are usually moderately interactive, meaning that you can either type in a key word or phrase to search the database, or make
Well, at least it is in some ways. For instance, e-learning allows you to learn anywhere and usually at any time, as long as you have a properly configured computer. Cell phones allow you to communicate any time and usually anywhere, as long as you have a properly configured phone.
E-learning can be CD-ROM-based, Network-based, Intranet-based or Internet-based. It can include text, video, audio, animation and virtual environments. It can be a very rich learning experience that can even surpass the level of training you might experience in a crowded classroom. It is self-paced, hands-on learning.
The quality of the electronic-based training, as in every form of training, is in its content and its delivery. E-learning can suffer from many of the same pitfalls as classroom training, such as boring slides, monotonous speech, and little opportunity for interaction. The beauty of e-learning, however, is that new software allows the creation of very effective learning environments that can engulf you in the material. We'll use software from Trainersoft as an example to show you how the process works.
Levels of e-learningE-learning falls into four categories, from the very basic to the very advanced. The categories are:
Knowledge databases -- While not necessarily seen as actual training, these databases are the most basic form of e-learning. You've probably seen knowledge databases on software sites offering indexed explanations and guidance for software questions, along with step-by-step instructions for performing specific tasks. These are usually moderately interactive, meaning that you can either type in a key word or phrase to search the database, or make
Benefits of E-learningE-learning has definite benefits over traditional classroom training. While the most obvious are the flexibility and the cost savings from not having to travel or spend excess time away from work, there are also others that might not be so obvious. For example:
It's less expensive to produce - Using Trainersoft's authoring software to produce your own asynchronous training programs, e-training is virtually free once you reach the break-even point. Synchronous programs will have continued costs associated with the instructor managing the class, but will still be lower than traditional courses.
It's self-paced - Most e-learning programs can be taken when needed. The "books" that you set up using Trainersoft create a module-based design allowing the learner to go through smaller chunks of training that can be used and absorbed for a while before moving on.
It moves faster - According to an article by Jennifer Salopek in "Training and Development Magazine," e-learning courses progress up to 50 percent faster than traditional courses. This is partly because the individualized approach allows learners to skip material they already know and understand and move onto the issues they need training on.
It provides a consistent message - E-learning eliminates the problems associated with different instructors teaching slightly different material on the same subject. For company-based training, this is often critical.
It can work from any location and any time - E-learners can go through training sessions from anywhere, usually at anytime. This Just-In-Time (JIT) benefit can make learning possible for people who never would have been able to work it into their schedules prior to the development of e-learning. (If you manage a corporate learning program, however, be careful about requesting that workers learn on their own time from home.)
It can be updated easily and quickly - Online e-learning sessions are especially easy to keep up-to-date because the updated materials are simply uploaded to a server. CD-ROM-based programs may be slightly more expensive to update and distribute, but still come out cheaper than reprinting manuals and retraining instructors.
It can lead to increased retention and a stronger grasp on the subject - This is because of the many elements that are combined in e-learning to reinforce the message, such as video, audio, quizzes, interaction, etc. There is also the ability to revisit or replay sections of the training that might not have been clear the first time around. Try that in a crowded auditorium!
It can be easily managed for large groups of students - Trainersoft Manager allows corporate training directors, HR managers and others to keep track of the course offerings, schedule or assign training for employees and track their progress and results. Managers can review a student's scores and identify any areas that need additional training.
It's less expensive to produce - Using Trainersoft's authoring software to produce your own asynchronous training programs, e-training is virtually free once you reach the break-even point. Synchronous programs will have continued costs associated with the instructor managing the class, but will still be lower than traditional courses.
It's self-paced - Most e-learning programs can be taken when needed. The "books" that you set up using Trainersoft create a module-based design allowing the learner to go through smaller chunks of training that can be used and absorbed for a while before moving on.
It moves faster - According to an article by Jennifer Salopek in "Training and Development Magazine," e-learning courses progress up to 50 percent faster than traditional courses. This is partly because the individualized approach allows learners to skip material they already know and understand and move onto the issues they need training on.
It provides a consistent message - E-learning eliminates the problems associated with different instructors teaching slightly different material on the same subject. For company-based training, this is often critical.
It can work from any location and any time - E-learners can go through training sessions from anywhere, usually at anytime. This Just-In-Time (JIT) benefit can make learning possible for people who never would have been able to work it into their schedules prior to the development of e-learning. (If you manage a corporate learning program, however, be careful about requesting that workers learn on their own time from home.)
It can be updated easily and quickly - Online e-learning sessions are especially easy to keep up-to-date because the updated materials are simply uploaded to a server. CD-ROM-based programs may be slightly more expensive to update and distribute, but still come out cheaper than reprinting manuals and retraining instructors.
It can lead to increased retention and a stronger grasp on the subject - This is because of the many elements that are combined in e-learning to reinforce the message, such as video, audio, quizzes, interaction, etc. There is also the ability to revisit or replay sections of the training that might not have been clear the first time around. Try that in a crowded auditorium!
It can be easily managed for large groups of students - Trainersoft Manager allows corporate training directors, HR managers and others to keep track of the course offerings, schedule or assign training for employees and track their progress and results. Managers can review a student's scores and identify any areas that need additional training.
There are many advantages to e-learning, and even the potential disadvantages (i.e. boring text-based courses, technophobia, loneliness) can be alleviated with a properly designed course. Let's move on now to how to plan a good course.
How Two-stroke Engines Work
How Two-stroke Engines Work
(Collected)
In this article, you'll learn all about the two-stroke engine: how it works, why it might be used and what makes it different from regular car and diesel engines.
You find two-stroke engines in such devices as chain shaw and jet skis because two-stroke engines have three important advantages over four-stroke engines:
· Two-stroke engines do not have valves, which simplifies their construction and lowers their weight.
· Two-stroke engines fire once every revolution, while four-stroke engines fire once every other revolution. This gives two-stroke engines a significant power boost.
· Two-stroke engines can work in any orientation, which can be important in something like a chainsaw. A standard four-stroke engine may have problems with oil flow unless it is upright, and solving this problem can add complexity to the engine.
· Two-stroke engines do not have valves, which simplifies their construction and lowers their weight.
· Two-stroke engines fire once every revolution, while four-stroke engines fire once every other revolution. This gives two-stroke engines a significant power boost.
· Two-stroke engines can work in any orientation, which can be important in something like a chainsaw. A standard four-stroke engine may have problems with oil flow unless it is upright, and solving this problem can add complexity to the engine.
These advantages make two-stroke engines lighter, simpler and less expensive to manufacture. Two-stroke engines also have the potential to pack about twice the power into the same space because there are twice as many power strokes per revolution. The combination of light weight and twice the power gives two-stroke engines a great power-to-weight ratio compared to many four-stroke engine designs.
You don't normally see two-stroke engines in cars, however. That's because two-stroke engines have a couple of significant disadvantages that will make more sense once we look at how it operates.
You don't normally see two-stroke engines in cars, however. That's because two-stroke engines have a couple of significant disadvantages that will make more sense once we look at how it operates.
Sparks Fly
You can understand a two-stroke engine by watching each part of the cycle. Start with the point where the spark plug fires. Fuel and air in the cylinder have been compressed, and when the spark plug fires the mixture ignites. The resulting explosion drives the piston downward. Note that as the piston moves downward, it is compressing the air/fuel mixture in the crankcase. As the piston approaches the bottom of its stroke, the exhaust port is uncovered. The pressure in the cylinder drives most of the exhaust gases out of cylinder, as shown here:
Fuel Intake
As the piston finally bottoms out, the intake port is uncovered. The piston's movement has pressurized the mixture in the crankcase, so it rushes into the cylinder, displacing the remaining exhaust gases and filling the cylinder with a fresh charge of fuel, as shown here:
Note that in many two-stroke engines that use a cross-flow design, the piston is shaped so that the incoming fuel mixture doesn't simply flow right over the top of the piston and out the exhaust port.
The Compression Stroke
Now the momentum in the crankshaft starts driving the piston back toward the spark plug for the compression stroke. As the air/fuel mixture in the piston is compressed, a vacuum is created in the crankcase. This vacuum opens the reed valve and sucks air/fuel/oil in from the carburetor.
Once the piston makes it to the end of the compression stroke, the spark plug fires again to repeat the cycle. It's called a two-stoke engine because there is a compression stroke and then a combustion stroke. In a four-stroke engine, there are separate intake, compression, combustion and exhaust strokes.
You can see that the piston is really doing three different things in a two-stroke engine:
· On one side of the piston is the combustion chamber, where the piston is compressing the air/fuel mixture and capturing the energy released by the ignition of the fuel.
· On the other side of the piston is the crankcase, where the piston is creating a vacuum to suck in air/fuel from the carburetor through the reed valve and then pressurizing the crankcase so that air/fuel is forced into the combustion chamber.
· Meanwhile, the sides of the piston are acting like valves, covering and uncovering the intake and exhaust ports drilled into the side of the cylinder wall.
It's really pretty neat to see the piston doing so many different things! That's what makes two-stroke engines so simple and lightweight.
If you have ever used a two-stroke engine, you know that you have to mix special two-stroke oil in with the gasoline. Now that you understand the two-stroke cycle you can see why. In a four-stroke engine, the crankcase is completely separate from the combustion chamber, so you can fill the crankcase with heavy oil to lubricate the crankshaft bearings, the bearings on either end of the piston's connecting rod and the cylinder wall. In a two-stroke engine, on the other hand, the crankcase is serving as a pressurization chamber to force air/fuel into the cylinder, so it can't hold a thick oil. Instead, you mix oil in with the gas to lubricate the crankshaft, connecting rod and cylinder walls. If you forget to mix in the oil, the engine isn't going to last very long!
Disadvantages of the Two-stroke
You can now see that two-stroke engines have two important advantages over four-stroke engines: They are simpler and lighter, and they produce about twice as much power. So why do cars and trucks use four-stroke engines? There are four main reasons:
· Two-stroke engines don't last nearly as long as four-stroke engines. The lack of a dedicated lubrication system means that the parts of a two-stroke engine wear a lot faster.
· Two-stroke oil is expensive, and you need about 4 ounces of it per gallon of gas. You would burn about a gallon of oil every 1,000 miles if you used a two-stroke engine in a car.
· Two-stroke engines do not use fuel efficiently, so you would get fewer miles per gallon.
· Two-stroke engines produce a lot of pollution -- so much, in fact, that it is likely that you won't see them around too much longer.
The pollution comes from two sources. The first is the combustion of the oil. The oil makes all two-stroke engines smoky to some extent, and a badly worn two-stroke engine can emit huge clouds of oily smoke. The second reason is less obvious but can be seen in the following figure:
Each time a new charge of air/fuel is loaded into the combustion chamber, part of it leaks out through the exhaust port. That's why you see a sheen of oil around any two-stroke boat motor. The leaking hydrocarbons from the fresh fuel combined with the leaking oil is a real mess for the environment.
These disadvantages mean that two-stroke engines are used only in applications where the motor is not used very often and a fantastic power-to-weight ratio is important.
You can understand a two-stroke engine by watching each part of the cycle. Start with the point where the spark plug fires. Fuel and air in the cylinder have been compressed, and when the spark plug fires the mixture ignites. The resulting explosion drives the piston downward. Note that as the piston moves downward, it is compressing the air/fuel mixture in the crankcase. As the piston approaches the bottom of its stroke, the exhaust port is uncovered. The pressure in the cylinder drives most of the exhaust gases out of cylinder, as shown here:
Fuel Intake
As the piston finally bottoms out, the intake port is uncovered. The piston's movement has pressurized the mixture in the crankcase, so it rushes into the cylinder, displacing the remaining exhaust gases and filling the cylinder with a fresh charge of fuel, as shown here:
Note that in many two-stroke engines that use a cross-flow design, the piston is shaped so that the incoming fuel mixture doesn't simply flow right over the top of the piston and out the exhaust port.
The Compression Stroke
Now the momentum in the crankshaft starts driving the piston back toward the spark plug for the compression stroke. As the air/fuel mixture in the piston is compressed, a vacuum is created in the crankcase. This vacuum opens the reed valve and sucks air/fuel/oil in from the carburetor.
Once the piston makes it to the end of the compression stroke, the spark plug fires again to repeat the cycle. It's called a two-stoke engine because there is a compression stroke and then a combustion stroke. In a four-stroke engine, there are separate intake, compression, combustion and exhaust strokes.
You can see that the piston is really doing three different things in a two-stroke engine:
· On one side of the piston is the combustion chamber, where the piston is compressing the air/fuel mixture and capturing the energy released by the ignition of the fuel.
· On the other side of the piston is the crankcase, where the piston is creating a vacuum to suck in air/fuel from the carburetor through the reed valve and then pressurizing the crankcase so that air/fuel is forced into the combustion chamber.
· Meanwhile, the sides of the piston are acting like valves, covering and uncovering the intake and exhaust ports drilled into the side of the cylinder wall.
It's really pretty neat to see the piston doing so many different things! That's what makes two-stroke engines so simple and lightweight.
If you have ever used a two-stroke engine, you know that you have to mix special two-stroke oil in with the gasoline. Now that you understand the two-stroke cycle you can see why. In a four-stroke engine, the crankcase is completely separate from the combustion chamber, so you can fill the crankcase with heavy oil to lubricate the crankshaft bearings, the bearings on either end of the piston's connecting rod and the cylinder wall. In a two-stroke engine, on the other hand, the crankcase is serving as a pressurization chamber to force air/fuel into the cylinder, so it can't hold a thick oil. Instead, you mix oil in with the gas to lubricate the crankshaft, connecting rod and cylinder walls. If you forget to mix in the oil, the engine isn't going to last very long!
Disadvantages of the Two-stroke
You can now see that two-stroke engines have two important advantages over four-stroke engines: They are simpler and lighter, and they produce about twice as much power. So why do cars and trucks use four-stroke engines? There are four main reasons:
· Two-stroke engines don't last nearly as long as four-stroke engines. The lack of a dedicated lubrication system means that the parts of a two-stroke engine wear a lot faster.
· Two-stroke oil is expensive, and you need about 4 ounces of it per gallon of gas. You would burn about a gallon of oil every 1,000 miles if you used a two-stroke engine in a car.
· Two-stroke engines do not use fuel efficiently, so you would get fewer miles per gallon.
· Two-stroke engines produce a lot of pollution -- so much, in fact, that it is likely that you won't see them around too much longer.
The pollution comes from two sources. The first is the combustion of the oil. The oil makes all two-stroke engines smoky to some extent, and a badly worn two-stroke engine can emit huge clouds of oily smoke. The second reason is less obvious but can be seen in the following figure:
Each time a new charge of air/fuel is loaded into the combustion chamber, part of it leaks out through the exhaust port. That's why you see a sheen of oil around any two-stroke boat motor. The leaking hydrocarbons from the fresh fuel combined with the leaking oil is a real mess for the environment.
These disadvantages mean that two-stroke engines are used only in applications where the motor is not used very often and a fantastic power-to-weight ratio is important.
Wednesday, February 14, 2007
Biometric & Multi-Biometric: A New Approach
A biometric system is essentially a pattern recognition system which makes a personal identification by determining the authenticity of a specific physiological or behavioural characteristic possessed by the user. An important issue in designing a practical system is to determine how an individual is identified depending on the context, a biometric system can be either a verification or an identification system. Various types of biometric systems are being used for real time identification, the most popular are based on face, iris and fingerprint matching. However there are other biometric systems that utilize retinal scan, speech recognition, signature & hand geometry; Biometric model is as-
Sensor Data
Feature Extension
Feature Vector
Matching(Template Stored in Database)
Match Score
Decision
In biometric authentication system generally suffer from enrollment problems due to non-universal biometric traits, biometric spoofing or insufficient accuracy caused by noisy data acquisition in certain environments.
Multi-biometric a relatively new approach to overcome these problems, it uses two or more biometric trait in the identify matching process. A multi –biometric system uses a multiple sensors for data acquisition. This allow it to capture multiple samples of a multiple biometric trait. Multi biometric system provide anti-spoofing measures by making it difficult for an intruder to simultaneously spoof the multiple biometric trait of a real user.
Types of multi-biometric system:-
1.Multi-model – It has the capacity to process and match identities by using more than one biometric mode such as finger print, face or iris.
2.Multi-Algorithmic – It can use more than one core matching algorithm developed by different vendors in order to reach optimal matching results.
3.Multi-Instance – It has the capacity to acquire & process more than one biometric traits (e.g. two fingers)
Multi-biometric systems are categorized into three-system architecture according to the strategies used for information fusion.
1. Fusion at the feature Extraction level – In this architecture, the information extracted from different sensors in encoded into a joint feature vector, which is then compared to an enrolment template (which is the joint feature vector stored in a database) and assigned a matching score as in a single biometric system.
2. Fusion at the matching score level – In this, the feature vector are created independently for each sensor & then compared to the enrolment templates, which are stored separately for each biometric trait. Based on the proximity of feature vector and template, each subsystem now its own matching score. These individual scores are finally combined into a total score, which is handed over to the decision modules.
3. Fusion at the decision level – In this fusion strategy, a separate authentication is made for each biometric trait. These decisions are then combine into a final vote.
Er. Mukesh Gothwal
Sr. Lecturer, Deptt. of CE/ IT
Instrumentation...
Instrumentation Engineering : An Introduction
Instrumentation provides the most thought-provoking and authoritative coverage of automation technologies, applications, and strategies to enhance automation professionals’ on-the-job success.
It addresses industry challenges, new technologies, and fundamentals in a practical approach written for engineers, managers, and other automation professionals.
Today’s era is of automation all industries are adopting new technologies in the field of automatic control like PLC’s & DCS based control. Only an Instrumentation Engineer can update these technologies effectively and efficiently.
Today in all type of Industries like Steel, Paper, Textile, Power plant, Cement, Refineries, Defense, Pharmaceutical, Biomedical and Research centers Instrumentation Engineer’s are playing a vital Role.
This branch covers new trends in automatic control like computer based automatic control, distributed control system, Smart sensor based control, automated guided vehicle, missiles launching control, traffic control, speed control, temperature control, pressure control, air craft or auto pilot control, RADAR satellite control, vehicle safety control, different chemical reaction controls etc.
Instrumentation provides the most thought-provoking and authoritative coverage of automation technologies, applications, and strategies to enhance automation professionals’ on-the-job success.
It addresses industry challenges, new technologies, and fundamentals in a practical approach written for engineers, managers, and other automation professionals.
Today’s era is of automation all industries are adopting new technologies in the field of automatic control like PLC’s & DCS based control. Only an Instrumentation Engineer can update these technologies effectively and efficiently.
Today in all type of Industries like Steel, Paper, Textile, Power plant, Cement, Refineries, Defense, Pharmaceutical, Biomedical and Research centers Instrumentation Engineer’s are playing a vital Role.
This branch covers new trends in automatic control like computer based automatic control, distributed control system, Smart sensor based control, automated guided vehicle, missiles launching control, traffic control, speed control, temperature control, pressure control, air craft or auto pilot control, RADAR satellite control, vehicle safety control, different chemical reaction controls etc.
Er. Neeraj Jain
Sr. Lecture, EI&C
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