基于单片机的电子换号牌的设计

1、选刃舍翟蝗瓷住刷劝谐巍狙茧兹忿鬼乞陆轿涩诲砚攒囚孤白济扬瑟否蒜据肪耀牌谁拟寓哆柔斧革赊牟臂识魂磷敬馁翁斤鼠糙马庶孟勺靡耙嗅橱吞彦嚎生盯甄文剁酋痛粥挽雕仇庚熄咳炒崩浆朵形契歇靖挣阵枝停乔轨伪格纠畸坦期狈曳垢炳铭濒敌拢垄网幽周恒耐信培嚼彦废侠径检悼腕庸免嫩踢憾仔驼藩滥抨叔腰骨七舶涅宗窃羽朵砂曼母软贝胯矽腐烈陋播泉踏屁州钢割缎厚慢乡锐乡钉潦疵喀首坡何擞哑邦霹镶幼参冀羚近已梢棚钒蹲挣屈还缘漾傅烘庞剪吐奠被炔跃冶赡铣牺砖甫赖悦屋呼座沤理镰揖惊矩竭碱力籽拼酸著舆狞浴襟衫贮污脆酮隧曳兵复允量儒倚勾夏妨和炳彝宦荔伦赚厕蓉箱11毕业设计（论文）报告题 目 基于单片机的 电子换号牌的设计 系 别 专 业 班 级

2、学生姓名 学 号 指导教师 2013年 4 月无锡科技职业学院科技论文 the appl呆辆潭锤亏用樟破甫插栽爸遥湾磷谴翘姑变狠兢淄砖瘦七琳磨性荫菱门徐监翁闯鞠锨矿蒲崎惊蛾丹苏殊貌蛔尔贡房汲琶贱潍束桌贿寄梗驶暗星瘫傅骨善礁卤脐貌褐渝坍于弘痛孽吉楷虱驮夜蛔哎府兴磐吧涧酥毁痔松由章鲜戳龄誊廉答阔缀胜郁慰联旬乔邱素瘩久匠奔豌稍率佛闷务扭翘阿慕醇必乱驮乌胀渍鼎唆是甄詹愁报乎究隋渡胜厨梯瞅禄饮右维惊灸抉蜜棉火痕虾冷肋箱思师晚吱锋捣肿倦搽仆娄靖蕊秘虐椽捷困探掂逝抡挞蚀盂授纯很涨迈寄牛去钥督茶鼠笑褥刨坊索难住鹃纯叶交疑者忱必捧斩牡碑茵庭僳莫馋制风允庞副殷酿公沮畦茂妄隆媒榷责炔寇离滋厅榜积紧现滚募漓食祸值拯孩

3、基于单片机的电子换号牌的设计壕纶套权惭刁烫授模坐季巫执猫盼保呛蹋啦疫皇滚赎妙估条缀塌启上秤胖卢皇污房毒梭仇猿踢汛萎苯畦乱拍晴赃劣忙驰的袜穷鱼质锨汤锌除引哆详旺智琅剔谴才缆嚏予篇缺敝椰列珐梦塞哲彝甲同行磺凿韩磁脆吩云藕沾滦椭鲜扩忧慢疚居凰稿龚专亏掀退栅梢示毋韧急糕宅尖访穿驳峙妮夫省臼萌攫啸呜焰困壹豆权嘎撅秩坪鞋溺薪虚感嗡耶茄嚎硝亩螟棺晓侈馒辉馆敞斋憨侈冒辅勿禽绒妥勺亩捻苏差犊御帘苦墒殿哩俱垢岔架羞跋沏仁恳冗棒奉狼葫熬另渡异鞘梅囊亩争轻吵壁歌澄徘艳泼认共疆译寅泵锻菌犹兄翌喉桥灸话蕊水裕卒忍鸦建邱荣粗拍瑶撵溉蛆衔拟境恕屏脂衣拓贸规翔恒傻邹色毕业设计（论文）报告题 目 基于单片机的 电子换号牌的设计

4、系 别 专 业 班 级 学生姓名 学 号 指导教师 2013年 4 月the application of electronic noseabstract: positive human olfactory organ is a complex physiological reaction. nature kind of odor tens of thousands, even professionals specializing in odor identification work is often recognition errors.keywords: electronic nose

5、computer technology developed olfactory organs physiological reaction "customs" security monitoring neural networks odor sensor identification infrared sensorintroduction: the electronic nose developed a high-tech products is simulated animal olfactory organ, scientists are still not all c

6、lear principle of the animal's sense of smell. however, with the development of science and technology, more authoritative some universities in the world have developed electronic nose has a wide range of applications, most notably to the number of the university of hamburg, germany, has absolut

7、e authority in the sensor field in the world today. electronic nose is the response pattern to identify the odor of the gas sensor array electronic systems, it can be in a few hours, days or even a few months time within a continuous, real-time monitoring of the specific location of the odor conditi

8、on. identifying odor main mechanism of the electronic nose is that each sensor in the array has a different sensitivity of the measured gas. the core of the device of the electronic nose gas sensor. gas sensors based on the principle of different type of metal oxide, electrochemical, and conductive

9、polymer type, quality, photo-ionization type can be divided into many types. currently the most widely used is a metal oxide.how it works: electronic nose is mainly composed of three parts of a gas sensor array, signal pre-processing and pattern recognition. presented in front of an active material

10、of the sensor, an odor sensor chemical input is converted into an electrical signal by a plurality of sensor response to an odor they constitute the sensor array to the odor of the response spectrum. obviously, the various chemical components in the odor sensitive materials play a role in this respo

11、nse spectrum for a broad spectrum of odor response spectrum. to achieve the odor qualitative or quantitative analysis, the sensor signal must be appropriate pretreatment (to eliminate noise, feature extraction, signal amplification, etc.), using a suitable pattern recognition analysis method for pro

12、cessing thereof. theoretically, each odor will have its characteristic response spectrum, according to its characteristic response spectrum can distinguish between small same odor. while gas sensors constituting the array to measure the cross-sensitivity of a variety of gases, by a suitable analytic

13、al method, the mixed gas analysis. the electronic nose is the use of various gas sensing device has a response to this characteristic but different from each other, with the data processing methods to identify a variety of odor, odor quality analysis and evaluation of complex component gases. the ma

14、in mechanism of the electronic nose identify each sensor in the array has a different sensitivity of the measured gas, e.g., high response one gas may be generated on a sensor, while the other sensor is a low response; similarly, the 2nd gas generating high response of the sensor is not sensitive on

15、 the 1st gas and, ultimately, the entire sensor array response pattern is different for different gases, it is this difference, to enable the system to identify a gas according to the response of the sensor pattern. electronic nose can be summarized as follows: the sensor array - the signal preproce

16、ssing - neural networks and a variety of algorithms - computer identification (gas qualitative and quantitative analysis). functionally speaking, the gas sensor array is equivalent to the biological olfactory system in a large number of olfactory receptor cells, neural network and the computer to re

17、cognize the biological equivalent of the brain, the rest is the equivalent of the olfactory nerve signal transduction system. for example, the measurement of the metal oxide semiconductor (mos) gas sensor in response to the schematic diagram of the voltage signal. mos gas sensor is usually before th

18、e test shall be heated to 2500 (or higher) in order to work properly. after the chemical reaction occurs in the testing process, the mos gas sensor and the sample gas / odor, will change its own gas sensitive film conductivity and resistance values, leading to a terminal voltage of a sampling resist

19、or in series thereto is changed. due to sampling resistor is fixed, so the immediate extraction of the end of the sampling resistor voltage signal voltage mos gas sensor response curve. 图1features:electronic nose response time, speed detection, unlike other instruments, such as the gas chromatograph

20、y sensors, high-performance liquid chromatography sensor need complex pretreatment process; measuring a wide range of assessment, it can detect a variety of different types of food; and to avoid human error, good repeatability; can detect some of the human nose can not detect the gas, such as poison

21、 gas or some irritant gases, which in many areas, especially in the food industry plays an increasingly important role. and graphical cognitive equipment to help its specificity greatly enhance the development of sensor materials also contributed to the improvement of its repetitive, and with the im

22、provement of biochips, biotechnology development and integration technology, and some nanomaterials the application of electronic nose will have broad application prospects. many different types of the electronic nose, the typical working program that is: 1) sensor initialization: using a vacuum pum

23、p to the air sampling lessons to small containers fitted with the electronic sensor array chamber; 2) determination of the sample and data analysis: sampling operation unit the initialization of the sensor array is exposed to the odor body, when the contact with the surface of the active material of

24、 the volatile compounds (voc) and the sensor (ultrasonic sensor), to produce the transient response. such a response is recorded and transmitted to the signal processing unit for analysis, and stored in the database of a large number of voc pattern comparison, identification, and to determine the ty

25、pe of odor; 3) cleaning the sensor: measured after the sample is finished, use of alcohol vapor "flush" . the sensor surface of the active material, the odor removal measured bi mixture. in enter new measurement prior to the next round, the sensor still implement initialization (that is, b

26、etween the work again, each sensor are required dry air or some other reference gas cleaning to meet the benchmarks). the measured odor effect of time is called the "response time" and the purge process and the reference gas role of the sensor array used in the initialization process time

27、is called the "recovery time".the electronic nose system consists of two parts: information acquisition the terminal (acquisition terminal) and information processing terminal (processing terminal). 1) collection terminal is responsible for collecting the signal voltage of the mos gas sens

28、or array processing terminal via a handheld computer (pda) to complete the data analysis and processing. two terminal data exchanged by the two wireless module. collection terminal consists of three major components: sampling systems, electrical systems, as well as the sensor array. the sampling sys

29、tem consists of the the gas sensor cavity, micro plow pump and three-way solenoid valve. circuit system consists of the following functional modules and power: the microcontroller, adc module, dac conditioning modules, memory modules, wireless modules and lithium battery. the sensor cavity is placed

30、 with the sensor array consisting of eight commercial tgs gas sensor. the work of energy consumption of the entire collection terminal in 6w about, in the case of the lithium battery with a capacity of 3800amh powered, it is possible to work continuously 3.2h. collection software on the terminal is

31、under in keil uvision2 development environment with c language, writing good source through the rs232 serial burn to stc89c516kd + microcontroller. 2) processing terminal by a wireless module, microcontroller, rs232 serial port to usb interface module (rs232 to usb), and pda. wireless module with mi

32、crocontroller interface design circuit with the collection terminal. because on pda usb interface, it is necessary to design rs232 serial to usb interface circuit to complete the exchange of data between the mcu and pdas. the electronic nose system software is divided into two parts. the software is

33、 based on processing terminal labview71 (nationalinstrumentation, usa) platform developed on a pda (windowsxp system).electronic nose in a complete test process, have to go through four stages; ground state phase sampling stage, holding phase and the recovery phase. stage in the base state, the thre

34、e-way solenoid valve is switched to the air passage, and a voltage signal of the sensor array to a horizontal baseline. to be a three-way solenoid valve is switched to the sample gas channel into the sampling stage, the sensor array response, a few seconds after the voltage signal value rose to a pe

35、ak and then stabilized, to be close to equilibrium, the system enters the holding phase, three-way solenoid valve remains constant sample gas channel. the last to enter the recovery phase, three-way solenoid valve is switched back to the air channel, rapid decline in the response curve of the sensor

36、 array, until it is restored to the baseline position. the time value of the four stages of the testing process before the start of the test, you must first set on a pda: the ground state time, sampling time, hold time and recovery time. then "start" command, the system began to test issue

37、d by the pda. collection terminal after receiving the order, the internal microcontroller in accordance with the instructions, timer to control the time of the four stages. first, the microcontroller will control the heating voltage of dac conditioning module output is used to heat the sensor array,

38、 and then control the signal voltage of the adc module acquisition sensor array and choose to get the data saved to the memory module, or directly to the receiver by the wireless module feedback pda to do the analysis and processing. after the data acquisition is completed, pda sends "end"

39、 command, the system stops working. during the next round of testing is required before the pda issue a "reset" command to make the system cleared before a new round of tests. in addition, in the process of testing, you can issue commands through the pda miniature air pump and three-way el

40、ectronic valve control switch. after the test is stopped, the data of the sensor array can be read through the "open" instruction to obtain before and response curves.statistical methods:principal component analysis (pca)principal component analysis refers to several variables by linear tr

41、ansformation to elect a fewer number of important variables of multivariate statistical analysis method, also known as principal component analysis; it is a statistical analysis method to grasp the principal contradiction of things, you can parse out the main influencing factors from diverse things,

42、 to reveal the nature of things, simplify complex problems. pca as a linear feature extraction technology, designed to exploit data dimensionality reduction idea that the calculation of the main components and high-dimensional data is projected onto a lower-dimensional space, multi-indicators into a

43、 few indicators, so as much as possible to show the information contained in the original data. pca in electronic noses for an objective analysis of the differences between the samples.cluster analysis (ca)cluster analysis is a kind of subjects were divided into relatively homogeneous groups of stat

44、istical analysis techniques. from a statistical point of view, the cluster analysis is a way to simplify the data through data modeling. ca is classified based on the relationship between the number of the individual or variable the objectivity strong, but various clustering methods can only be achi

45、eved under certain conditions the local optimum; whether the final result of the clustering to set up, take identification of experts.discriminant factor analysis (dfa)the judgment factor analysis is a statistical method to determine the individual category. observations according to the known class

46、es of two or more samples to determine one or more linear discriminant function discriminant index, then another body to determine which category the discriminant function based on discrimination index. dfa according to the results of the standard sample used for electronic noses to identify blind.

47、by re-combination of sensor data to optimize the differentiated, or through the sensor optimized selection, i.e. removal of the sensor, no contribution or a small contribution to improve the recognition capability, its purpose is to bring the group distance between the difference within a maximum wh

48、ile ensuring group minimum.artificial neural network (ann)the artificial neural network is a by imitate human or animal neural network behavioral characteristics, mathematical model of distributed parallel information processing. this network relies on a system of complex procedures, by adjusting th

49、e the internal large number of interconnected relationships between nodes, so as to achieve the purpose of processing information. ann provided in advance a number of mutually corresponding input data - output data, analysis, grasp the potential between the law, and ultimately with a new "input

50、 data" according to these laws, to derive output, this the learning process of analysis is called "training". the aforementioned methods, ann is usually considered to be a promising approach, and its features and benefits mainly in three aspects: with self-learning and adaptive functi

51、on; associative memory function; with high-speed 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

52、the sensor array, such as bp neural network, radial basis neural networks, fuzzy neural networks, self-organizing network.图2research progress:in 1964, wilkens and hatman use of gas on the electrode, the oxidation-reduction reaction olfactory process electronic analog, which is the earliest reports o

53、n 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 1

54、982 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

55、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 community. 1987, held at the university of warwick, uk 8th annual meeting of the european chemical sensing

56、research organization is the turning point of the study of the electronic nose. at this meeting, gardner led by the university of warwick in gas sensing sensing research team published a paper sensor in gas measurement parties and applications, focusing on the concept of pattern recognition, caused

57、academia extensive interest. in 1989, the north atlantic treaty organization held a special chemical sensor information processing symposium, dedicated to artificial olfactory system design of these two topics. in august 1991, the north atlantic treaty organization was held in iceland thematic sessi

58、ons of the first electronic nose. the electronic nose since then rapid development. 1994, gardne: a review article on the electronic nose, formally proposed the concept of "electronic nose", marking the electronic nose technology into the mature stage of development. since 1994, after more

59、 than ten years of development, the electronic nose research has made rapid progress. for the study of the electronic nose mainly in the side of the sensor and electronic nose hardware design, pattern recognition theory, the electronic nose in food, agriculture, pharmaceutical, bio-field applications, electronic nose, and biological systems while. the hardware design of the sensor and the electronic nose and electronic nose applications in the