12-08-2015, 01:15 PM
sir please give me info about e nose
i want seminar report also.
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electronic nose seminars report pdf download
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sir please give me info about e nose
i want seminar report also.
24-02-2017, 12:32 PM
Abstract
In a developing world, where electronic devices are doubling any other sense of perception, the sense of smell is lagging behind. However, recently, there has been an urgent increase in the need to detect odors, to replace human work detection and quantification.
Some of the most important applications fall into the category in which humans can not afford the risk of sniffing the substance. Other important applications are continuous monitoring, medical applications, etc. These applications allow the man to perform tasks previously considered impossible. The fast-paced technology has helped develop sophisticated devices that have taken the electronic nose to miniature sizes and advanced capabilities. The trend is such that there will be precise, qualitative and quantitative measurements of smell in the near future.
Living beings interact with the environment through particular interfaces called senses, which can be divided into two groups: those that detect the physical quantities and those that detect the chemical quantities.
Physical interfaces (dealing with acoustic, optical, temperature and mechanical interaction mechanisms) are well known and a great number of successful studies have been done to construct their artificial counterparts in recent years. On the other hand, the chemical interfaces (bio transducers of the chemical species in the air: smell, and solution: flavor), although well described in the literature, present some aspects of their physiological work principle that are not yet clear. It is also important to emphasize a psychological difference in humans between the two groups.
In fact, the information of the physical senses can be properly elaborated, verbally expressed, firmly memorized and fully communicated. On the contrary, the chemical information from the nose and tongue is surrounded by vagueness, which is reflected in the poor description and memorability of the olfactory and tasting experiences. Chemical information is of primary importance for most animals; For many of them, indeed, chemistry is the only area they deal with, whereas for humans evolution has only improved physical interfaces, leaving little care of the chemical interface, if we exclude unconscious acquisition and behaviors Secondary.
For these intrinsic difficulties in understanding the nature of these senses for many years, only sporadic research on the possibility of making artificial olfactory systems was carried out. It was only in the late 1980s that a promising new approach was introduced. It was based on the assumption that a series of non-selective chemical sensors paired with a suitable data processing method could mimic the olfaction functions.
In the last decade, electronic instrumentation of the nose has generated much international interest in its potential to solve a wide variety of problems in the fragrance and production of cosmetics, food and beverage manufacturing, chemical engineering, environmental monitoring and , More recently, medical diagnostics and bioprocesses. Several dozen companies are now designing and selling electronic nose units worldwide for a wide variety of expanding markets. An electronic nose is a machine that is designed to detect and discriminate between complex odors using an array of sensors. The sensor set consists of highly tuned (non-specific) sensors that are treated with a variety of biological or chemical materials sensitive to odors.
An odor stimulus generates a characteristic fingerprint (or fingerprint-print) of the sensor array. Patterns or fingerprints of known odors are used to build a database and train a pattern recognition system so that unknown odors can be further classified and identified. Therefore, electronic nose instruments are composed of hardware components to collect and transport odors to the array of sensors - as well as electronic circuitry to digitize and store the sensor responses for signal processing.
Principle of E-nose
Mimicking the nose is a difficult task. The human nose can smell 10,000 different odor molecules mixed in the air. The odor in a substance is due to certain volatile organic compounds (VOCs), which evaporate easily and are transported by a stream of air. An e-nose can smell and estimate odors quickly, although it has little or no resemblance to the human nose.
A human nose has receptors, which serve as binding sites for VOCs. A receptor is only a molecular structure on the surface of the nerve cell to which an odorous molecule with the right form is attached. The receptor and the binding molecule are adjusted exactly as in a key and lock arrangement. These nerve cells that detect odors align the top of the cavity in the human nose.
Once an odor molecule is attached to a receptor, it follows a chain reaction that finally transmits an electrical signal to the brain. A specific smell of coffee or wine is usually caused not by one, but a mixture of hundreds of organic compounds. Therefore, the brain has a gigantic task of processing the signals received from the nerve cells coming from the nose, to identify the nature of the smell. The exact functioning of the brain in the processing of these signals is not yet fully understood.
An electronic nose can be defined as "an instrument that is composed of a series of electronic chemical sensors with partial specificity and an appropriate pattern recognition system capable of recognizing simple or complex odors (and other gaseous mixtures). Electronics to quickly discriminate between slight variations in complex mixtures makes the techniques ideal for online process diagnostics and screening in a wide range of application areas.An electronic nose is a machine that is designed to detect and discriminate between odors Using an array of sensors.
The sensor set consists of highly tuned (non-specific) sensors that are treated with a variety of biological or chemical materials sensitive to odors. An odor stimulus generates a characteristic fingerprint (or fingerprint-print) of the sensor array. Patterns or fingerprints of known odors are used to build a database and train a pattern recognition system so that unknown odors can be further classified and identified. Therefore, electronic nose instruments are made up of hardware components to collect and transport odors to the sensor array - as well as electronic circuitry to digitize and store the sensor responses for signal processing.
The two main components of an electronic nose are the detection system and the automated pattern recognition system. The detection system may be an array of several different detection elements (eg, chemical sensors), wherein each element measures a different property of the detected chemical, or may be a single detection device (eg spectrometer) that Produces an array of measurements for each chemical, or it can be a combination. Each chemical vapor presented to the sensor set produces a signature or pattern characteristic of the vapor. By presenting many different chemicals to the sensor array, a database of signatures is created. This database of tagged signatures is used to train the pattern recognition system.
The purpose of this training process is to configure the recognition system to produce unique classifications of each chemical so that an automated identification can be implemented. The amount and complexity of the data collected by the set of sensors may hinder conventional chemical analysis of data in an automated manner. One approach to chemical vapor identification is to construct an array of sensors, where each sensor in the array is designed to respond to a specific chemical. With this approach, the number of unique sensors must be at least as large as the number of chemicals being monitored. It is expensive and difficult to construct highly selective chemical sensors. Artificial neural networks (RNAs), which have been used to analyze complex data and recognize patterns, are showing promising results in chemical vapor recognition.
In a developing world, where electronic devices are doubling any other sense of perception, the sense of smell is lagging behind. However, recently, there has been an urgent increase in the need to detect odors, to replace human work detection and quantification.
Some of the most important applications fall into the category in which humans can not afford the risk of sniffing the substance. Other important applications are continuous monitoring, medical applications, etc. These applications allow the man to perform tasks previously considered impossible. The fast-paced technology has helped develop sophisticated devices that have taken the electronic nose to miniature sizes and advanced capabilities. The trend is such that there will be precise, qualitative and quantitative measurements of smell in the near future.
Living beings interact with the environment through particular interfaces called senses, which can be divided into two groups: those that detect the physical quantities and those that detect the chemical quantities.
Physical interfaces (dealing with acoustic, optical, temperature and mechanical interaction mechanisms) are well known and a great number of successful studies have been done to construct their artificial counterparts in recent years. On the other hand, the chemical interfaces (bio transducers of the chemical species in the air: smell, and solution: flavor), although well described in the literature, present some aspects of their physiological work principle that are not yet clear. It is also important to emphasize a psychological difference in humans between the two groups.
In fact, the information of the physical senses can be properly elaborated, verbally expressed, firmly memorized and fully communicated. On the contrary, the chemical information from the nose and tongue is surrounded by vagueness, which is reflected in the poor description and memorability of the olfactory and tasting experiences. Chemical information is of primary importance for most animals; For many of them, indeed, chemistry is the only area they deal with, whereas for humans evolution has only improved physical interfaces, leaving little care of the chemical interface, if we exclude unconscious acquisition and behaviors Secondary.
For these intrinsic difficulties in understanding the nature of these senses for many years, only sporadic research on the possibility of making artificial olfactory systems was carried out. It was only in the late 1980s that a promising new approach was introduced. It was based on the assumption that a series of non-selective chemical sensors paired with a suitable data processing method could mimic the olfaction functions.
In the last decade, electronic instrumentation of the nose has generated much international interest in its potential to solve a wide variety of problems in the fragrance and production of cosmetics, food and beverage manufacturing, chemical engineering, environmental monitoring and , More recently, medical diagnostics and bioprocesses. Several dozen companies are now designing and selling electronic nose units worldwide for a wide variety of expanding markets. An electronic nose is a machine that is designed to detect and discriminate between complex odors using an array of sensors. The sensor set consists of highly tuned (non-specific) sensors that are treated with a variety of biological or chemical materials sensitive to odors.
An odor stimulus generates a characteristic fingerprint (or fingerprint-print) of the sensor array. Patterns or fingerprints of known odors are used to build a database and train a pattern recognition system so that unknown odors can be further classified and identified. Therefore, electronic nose instruments are composed of hardware components to collect and transport odors to the array of sensors - as well as electronic circuitry to digitize and store the sensor responses for signal processing.
Principle of E-nose
Mimicking the nose is a difficult task. The human nose can smell 10,000 different odor molecules mixed in the air. The odor in a substance is due to certain volatile organic compounds (VOCs), which evaporate easily and are transported by a stream of air. An e-nose can smell and estimate odors quickly, although it has little or no resemblance to the human nose.
A human nose has receptors, which serve as binding sites for VOCs. A receptor is only a molecular structure on the surface of the nerve cell to which an odorous molecule with the right form is attached. The receptor and the binding molecule are adjusted exactly as in a key and lock arrangement. These nerve cells that detect odors align the top of the cavity in the human nose.
Once an odor molecule is attached to a receptor, it follows a chain reaction that finally transmits an electrical signal to the brain. A specific smell of coffee or wine is usually caused not by one, but a mixture of hundreds of organic compounds. Therefore, the brain has a gigantic task of processing the signals received from the nerve cells coming from the nose, to identify the nature of the smell. The exact functioning of the brain in the processing of these signals is not yet fully understood.
An electronic nose can be defined as "an instrument that is composed of a series of electronic chemical sensors with partial specificity and an appropriate pattern recognition system capable of recognizing simple or complex odors (and other gaseous mixtures). Electronics to quickly discriminate between slight variations in complex mixtures makes the techniques ideal for online process diagnostics and screening in a wide range of application areas.An electronic nose is a machine that is designed to detect and discriminate between odors Using an array of sensors.
The sensor set consists of highly tuned (non-specific) sensors that are treated with a variety of biological or chemical materials sensitive to odors. An odor stimulus generates a characteristic fingerprint (or fingerprint-print) of the sensor array. Patterns or fingerprints of known odors are used to build a database and train a pattern recognition system so that unknown odors can be further classified and identified. Therefore, electronic nose instruments are made up of hardware components to collect and transport odors to the sensor array - as well as electronic circuitry to digitize and store the sensor responses for signal processing.
The two main components of an electronic nose are the detection system and the automated pattern recognition system. The detection system may be an array of several different detection elements (eg, chemical sensors), wherein each element measures a different property of the detected chemical, or may be a single detection device (eg spectrometer) that Produces an array of measurements for each chemical, or it can be a combination. Each chemical vapor presented to the sensor set produces a signature or pattern characteristic of the vapor. By presenting many different chemicals to the sensor array, a database of signatures is created. This database of tagged signatures is used to train the pattern recognition system.
The purpose of this training process is to configure the recognition system to produce unique classifications of each chemical so that an automated identification can be implemented. The amount and complexity of the data collected by the set of sensors may hinder conventional chemical analysis of data in an automated manner. One approach to chemical vapor identification is to construct an array of sensors, where each sensor in the array is designed to respond to a specific chemical. With this approach, the number of unique sensors must be at least as large as the number of chemicals being monitored. It is expensive and difficult to construct highly selective chemical sensors. Artificial neural networks (RNAs), which have been used to analyze complex data and recognize patterns, are showing promising results in chemical vapor recognition.
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