【正文】 s Bloodhound. Domestic gas sensor has been developed rapidly in recent years, but pared to the overall foreign advanced countries quite different.Conclusion: Overall, most of the domestic and international electronic nose technology is still in the laboratory stage, even if 。s latest two technologies solid phase micro extraction and Electronic Nose monitor phenanthrene degradation in contaminated soil. The Philippines is a hydrophobic organic contaminants, contains three fused benzene rings belonging to polycyclic aromatic hydrocarbons. The detection and analysis of the electronic nose results show that, by PCA treatment, contaminated and uncontaminated soil samples can be significant distinction.Public SafetyIn order to ensure the security of public places, check explosives in airports, railway stations, docks and other places is an important and difficult task. These places usually have more staff, speed of flow of people, plex background, more belongings. Therefore, the accuracy of these places explosives, quick detection has bee the focus of the work and difficult. Compared to traditional detection methods, the electronic nose has small size, low cost, and high reliability. . Yinun and other electronic nose for explosives and chemical weapons detection of volatile gases. With polymer coating Iran and other electronic nose sensor array for the war moving analog classification, warning of an impending threat of chemical weapons, people to safely leave the contaminated area. In summary, the electronic nose has a short response time, speed detection, sample preparation is simple determination of the wide scope of the assessment, objective assessment of odor pensate for the description of human sensory ambiguity, subjectivity and imprecision, and gas chromatography plicated shortings. Painstaking research, researchers in various fields from a single sensing element to the sensor array to the image sensor, the electronic nose technology fruitful research results. Many foreign advent of electronic nose products, such as France, Alpha MOS system is mainly used for quality identification products such as meat, coffee, cereals, UK Aroma SCAN system is mainly used for cheese, meat quality testing, there39。Amico pointed out that the electronic nose can distinguish between benign skin lesions and birthmarks tumor or melanoma。s renal function, mental patients appreciate. The electronic nose in another medical application is the detection of cancer. The proposed electronic nose Italy and other noninvasive diagnosis of early cancer of the urinary tract。 detect ear, nose and throat infections reach up to 88% accuracy。 application of a precise verification techniques and the detection output of the steps on the selected model. The electronic nose applied to the assessment of the quality of black tea in India Bipan Tudu to do related research. Based on neural network in dealing with the main problems of sensor array data: the quality of black tea, tea from different tea gardens picked by different climatic conditions, farm type, season and planting methods are quite different, and therefore, the entire database can not be readily be met difficult to train a neural network model. The study proposed to enhance the learning characteristics of RBF neural network pattern recognition algorithms to classify the smell of black tea, and get a better recognition effect. In addition, the Task Force also uses an electronic nose to predict the optimum fermentation time for black tea. Wang Jun, et al Zhejiang University to study electronic nose applications in various types of food, such as Longjing tea, wheat, eggs, etc., have achieved better results. Luo Dehan such as China Science and Technology University of Electronic Nose to the counterfeit cigarettes identification, Huazhong University of Science and Technology, Xie Changsheng electronic nose to identify 17 different brands of domestic vinegar.MedicineWith the development of electronic nose technology and its application in the field of medicine is being increasingly popular. ERThaler in electronic nose applications early, in order to verify whether it applies to the field of medicine do exploratory test. The experiments showed that the electronic nose can better distinguish the cerebrospinal fluid and plasma, high accuracy, you need a small amount of sample. The experiment took the first step to explore the feasibility of electronic nose applications in the field of medicine. Clinically, the electronic nose for evaluation of halitosis。 with highspeed to find the optimal solution capacity. In addition, it is able to solve nonlinear problems better than the traditional statistical methods in dealing with noise and drift. Currently, many artificial neural network is used for processing the signal of the sensor array, such as BP neural network, radial basis neural networks, fuzzy neural networks, selforganizing network.圖2Research progress:In 1964, Wilkens and Hatman use of gas on the electrode, the oxidationreduction reaction olfactory process electronic analog, which is the earliest reports on the electronic nose. 1965, Buck et al the use of changes in the conductance of a metal and a semiconductor gas measurement, Dravieks then using the change in contact potential measurements of the gas. However, as the gas classification with the concept of intelligent chemical sensor arrays until 1982 by the University of Warwick, UK Persuad et al, their electronic nose system consists of two parts of the gas sensor array and pattern recognition system. The sensor array part of the mountain three semiconductor gas sensor. This simple system can distinguish between the brain, according to the tree rose oil, clove oil, volatile chemical substances for dental odor. In the next five years, the electronic nose research and did not cause extensive attention in the international academic munity. 1987, held at the University of Warwick, U