【作者】 夏东海；

【导师】 王殊；

【作者基本信息】 华中科技大学 ， 信息与通信工程， 2008， 博士

【摘要】 在社会经济快速发展过程和构建和谐社会进程中,社会生活中的公共安全问题与经济生产运行中的能源紧缺问题已成为制约经济快速发展和构建和谐社会的瓶颈,日益受到人们的广泛关注。因此,发展新的气体信息获取及其信号处理技术方法来加强对公共安全的监测和预警,以及开发新的清洁生物能源感知探测与生产控制技术来替代日益减少和不可再生的化石能源,将具有十分重要的实际工程应用意义。在以往气体探测技术方法中,对于气体的本征感知属性信息的探测技术研究较多,如气体的温度和浓度等,但随着发展的需要,人们不再满足于现有的气体探测技术,而试图获取气体的空间信息,如空间方位信息。因此,气体空间信息探测技术研究已成为当前气体探测及其智能信号处理的研究内容之一。在气体信号源方位探测技术的应用研究方面,主要通过对公共安全与生物能源领域的气体信号探测应用研究,提出了包括狭长空间和宽平空间在内的气体信号源方位探测的方法研究需求与问题,阐明了气体信号源方位探测的实际工程应用的意义和目的。如在公共安全领域,利用气体信号源方位探测技术可以实现对火灾火源的快速定位,从而缩短火灾探测报警时间,有利于人员安全疏散;在生物能源领域,利用气体信号源方位探测技术可以实现对生物燃气气源的定位,有利于于生物燃气生产系统的燃气采集、输运的控制操作,以实现规模化连续工业生产。气体信号源方位探测是气体空间信息探测的一个基本内容。本论文针对实际工程应用的需求和应用特点,结合气体扩散流动的一些基本规律和特征性质,对气体的空间信息探测——气体信号源方位探测的基本方法原理与计算算法等关键技术,以及相关领域的应用研究问题进行了深入研究与探讨。本论文所取得的研究成果包括以下几个方面:1.在气体扩散理论与模型的研究方面,从实际工程应用背景出发,通过研究与分析包括一般流体、湍流、湍流扩散、连续点源的湍流扩散以及浮力羽流与平面射流等气体扩散的基本规律、理论和应用等,从中得到如下特性:(1)在狭长空间中气体扩散会沿一定方向扩散,且气体浓度分布呈现递减的变化趋势;(2)在宽平的空间中气体扩散,气体浓度梯度会在空间顶部平面上围绕一个中心点沿着顶部水平呈圆形以一定的速率向四周扩散,呈现出以一个中心点为圆心的浓度梯度分布的平面波扩散形式特征。这些研究结论为后续的气体信号源探测方法的理论研究与建立提供了基础性的依据,开辟了新的研究方向和新思路。2.在狭长空间气体信号源方位探测的方法研究方面,将探测传感器阵列引入气体信号采集过程,将Rough集的数学方法工具引入气体探测信号处理的计算模型,提出了狭长空间气体信号源方位探测的基本原理,给出了一种基于Rough测度的狭长空间气体信号源方位探测算法,该算法通过计算各个传感器阵元上采样信号的Rough测度,来发现信号空间中的极化特征,并结合狭长空间内气体扩散特性,确定气体信号源的方位,仿真计算分析了该方法的适用性和稳健性等问题。3.在宽平空间气体信号源方位探测的方法研究方面,根据气体在宽平空间内的浓度扩散分布特性,并基于不改变现有的传感器技术的考量,从传感器阵列的信号处理角度出发,提出了基于双线传感器阵列的宽平空间气体信号源方位探测方法,给出了其基于双线阵列信号时延估计的理论计算算法,并通过仿真计算分析了该方法的适用性和稳健性等问题。本论文的研究成果主要应用于对气体信号源方位的探测识别,从而实现对气源的发现与定位。它一方面可以适用于对方位探测要求不高的应用场景,如狭长空间气体信号源方位探测,另一方面也可以适用于对方位探测要求较高的应用场景,如宽平空间气体信号源方位探测。更多还原

【Abstract】 In the course of the high development of the society and economy in china with the demand of constructing the harmonious society by people, the public security in the social living and the serious energy lack in the expanding industry and economy are becoming the bottlenecks to that progressing course increasingly. For solving these, the new technologies are urgently investigated to enhance the monitoring and forewarning ability of the public security, and develop the new clean bioenergy instead of the increasingly reduced and non-reproducible fossil energy. In all these processes of observing, apperceiving, detecting and monitoring the application system in the area of the social living and industrial production for the new technologies, the methods and technologies of the gas information acquisition and the gas signal processing are playing the crucial roles. However, in the past, the researches are focused on the information acquisition of root property to the detected gas, e.g. the gas temperature and the gas concentration. With the demand of the technology development increased, it is satisfied by people not only to acquire the root property of the gas information, but also to acquire the space property of the gas information for feedback controlling the application system via mining the obtained information, e.g. the space information of the gas source orientation. Therefore, the detection methods of the gas space information in the various application backgrounds of engineering are becoming an important research direction of the gas detection and the intelligent signal processing currently.qThe application research on the detection technology of the gas signal source orientation, the research requirements and issues, viz. the researches of the theoretic methods to the detection of the gas signal source orientation in the narrow space and the plane space, are presented firstly by discussing the applications of the gas signal detection in the areas of the public security and the bioenergy. And the application purposes of the detection for the gas signal source orientation are illustrated secondly. For example, in the area of the public security, it is indicated that the fast fire source localization by using the detection technology of the gas signal source orientation is available to realize the optimizing control of people evacuation in fire, via. the application research of the fire detection in nonage, i.e. the fast fire source localization can sharply decrease the alarm time of the fire detection, viz. correspondingly prolong the time of people evacuating, to ensure the safety of people evacuation. And in the area of the bioenergy, it is indicated that the fast biogas source localization by using the detection technology of the gas signal source orientation is available to realize the optimizing control of the production system of the biogas collection for the large and continuous producing via. the application research of the biogas detection, collecting and generating electricity.The detection of the gas signal source orientation is a basic detecting task of the gas space information. Combining with the basic principles and specialities of the gas diffusion, the key technologies adapted with the demand of practical applications, involving of the methods, theories, algorithms, are lucubrated and discussed in the thesis. And the main researches of the thesis are presented in the followings.In the first part, i.e. the application research on the gas diffusion theories and models, the characters and specialities of the gas diffusion in the certain space are acquired via. analyzing the gas diffusion models and applications based on the practical engineering, involving the fluid, the turbulence, the turbulent diffusion, the turbulence diffusion with a continuous point-source, plume flow and jet flow. There are two characters researched in the part, the one is that the gas concertration is decreased with time moving when the gas diffusing in a certain direction in the narrow space, and the other is that the gas concertration grads is distributed around with a certain centre point and diffused to the all directions by the type of circle simulating as a planar wave in the plane space. And these studies provide the theoretic supports for establishing the detection methods of the gas signal source orientation in the following and the new investigation direction.In the second part, i.e. the research on the detection of the gas signal source orientation in the narrow space, the thesis presents the method of the detection of gas signal source orientation in the narrow space, via. applying the detection sensor array in the gas signal sampling, using a mathematic tool based on the rough set theory for the computation. And then an algorithm based on the rough measure for the detection method is given, in which for the goal of estimating the gas signal source orientation, the polarization characteristics of sampling signal space of gas concertration is obtained via. computing the rough measure. Lastly the applicability and robustness of the method are discussed via. the algorithm simulations.In the third part, i.e. the research on the detection of the gas signal source orientation in the plane space, the thesis studies the gas plane diffusion characters and gas concentration distribution, and presents the method of the detection of gas signal source orientation in the plane space, which is based on dual-line gas sensor array and not to change the current technology of gas sensor. And then an algorithm based on the time delay estimation of the signals from the dual-line array for the detection method is given, and the applicability and robustness of the method are discussed via. the algorithm simulations.The achievements of the research work in this thesis can be used to detect the gas signal source orientation for the localization and discovery of the gas source, where the detection method of the gas signal source orientation in the narrow space is applied in the scenes of lower requirement for the orientation detection, and the detection method of the gas signal source orientation in the plane space is applied in the scenes of higher requirement for the orientation detection.更多还原