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81.
提出了3种基于知识的管道系统泄漏检测方法,分别是:通过对负压波波形分段符号化处理,采用上下文无关法表示波形结构模式的模式识别诊断系统;以选取合适维数的功率谱特征向量而建立的神经网络泄漏检测系统;与泄漏机理数学模型结合的泄漏诊断专家系统。  相似文献   
82.
基于属性识别的高速公路交通安全评价模型   总被引:5,自引:4,他引:1  
针对高速公路交通安全问题,利用属性数学中的识别理论对其进行研究。在对影响高速公路交通安全因素综合分析基础上,构建了高速公路交通安全评价的指标体系;在利用五级标度法确定评价指标权重系数的情况下,建立了基于属性识别的高速公路交通安全评价模型;评价模型根据单指标的属性测度值与多指标的综合属性测度值,利用置信度准则来识别高速公路交通安全的现状水平。应用实例表明:利用属性评价模型,可以找出影响高速公路交通安全的问题成因和限制因素,为高速公路规划和改造提供科学决策依据。  相似文献   
83.
84.
重大工业事故隐患辨识与评价方法研究   总被引:2,自引:2,他引:2  
从导致事故发生的两类危险源理论出发,结合重大危险源和重大工业事故隐患之间的相互关系,揭示进行重大工业事故隐患辨识和评价的本质就是对危险控制措施和控制能力的评价,即对重大危险源采取的控制措施是否到位,能否有效控制事故的发生。该方法通过对工业单元固有的事故易发性和所采取措施的控制能力二者之间是否满足必要的受控关系,作为重大危险源是否构成重大工业事故隐患的判断依据。在工业生产中的应用该法,可以客观反映危险源的危险控制情况,便于危险源所在单位及时加强技术干预,减少事故发生。  相似文献   
85.
Summary. Recent studies have demonstrated that under weakly acidic conditions (pH 6.0), many prey fishes, including juvenile rainbow trout (Onchorhynchus mykiss), do not exhibit overt antipredator responses to conspecific chemical alarm cues. In laboratory trials, we investigated the potential effects of reduced pH on the ability of hatchery reared, predator naïve juvenile rainbow trout to acquire the recognition of a novel predator (yellow perch, Perca flavenscens). Initially, we exposed trout to the odour of a predatory yellow perch, buffered to pH 6.0 (weakly acidic) or pH 7.0 (neutral) paired with conspecific skin extracts (also buffered to pH 6.0 or 7.0) or a distilled water control. Juvenile trout exhibited significant increase in antipredator behaviour when exposed to neutral skin extract (pH 7.0). When retested 48 hours later to perch odour alone (pH 7.0), only trout initially conditioned with neutral skin extracts (pairs with either neutral or acidic perch odour) exhibited a learned recognition of perch odour as a predator risk. Those initially exposed to weakly acidic skin extract or the distilled water control did not show a learned response to predator odour. These results demonstrate that the ability to acquire the recognition of novel predators is impaired under weakly acidic conditions, as would occur in natural waterways affected by acidic precipitation.  相似文献   
86.
We studied the factors that enhance food recognition and consumption in young canaries when confronted with adults. In contrast to previous studies on canaries, in which social transmission of food habits was studied in the context of dyadic interactions (one juvenile–one adult), we proposed a more realistic framework in which young canaries were studied in the context of triadic interactions, free or not, with adults of both sexes. We found that during free interactions, the young bird only eats with a familiar male and that this association enhances the social transmission of seed handling. When the juvenile was separated from the adults by a transparent partition, it only learned to husk seed if it was present at the feeder at the same time as a familiar adult acting as a demonstrator. The presence of adults that are familiar but do not act as demonstrators does not facilitate social transmission of handling. However, the presence of a familiar, demonstrating female had also no effect on this transmission. Coordination of the actions of the experienced bird and of the naive subject is required for social transmission to occur. Action coordination does not depend solely on the level of familiarity between partners but also on the role played by the demonstrator (here, the adult male) that looks after the juvenile during its transition towards independence.  相似文献   
87.
公路滑坡灾害链式反应阶段性识别方法研究   总被引:5,自引:2,他引:3  
马保成  王亮  牟顺 《灾害学》2011,26(2):54-58
为了对公路滑坡的发育阶段做出准确判别,研究了公路滑坡灾害发育的链式反应机理,将滑坡的发育阶段划分为3个阶段。采用广泛调研和专家咨询的技术手段,从发育阶段的表现特征中选定了滑坡识别的相关因素集和评分,在此基础上采用模糊数学的方法对公路滑坡灾害的发育阶段进行了识别,并在陕南公路滑坡调查中初步应用。  相似文献   
88.
Genetic relatedness of the mound-building ant Formica pratensis was determined by means of microsatellite DNA polymorphism, and its impact on nestmate recognition was tested in a population in Southern Sweden (Oeland). Recognition between nests was measured by testing aggression levels between single pairs of workers. The genetic distances of nests (Nei's genetic distance) and the spatial distance of nests were correlated and both showed a strong relation to the aggression behavior. Multiple regression analysis revealed a stronger impact of genetic relatedness rather than spatial distances on aggression behavior. Neighbouring nests were more closely related than distant nests, which may reflect budding as a possible spreading mechanism. The genetic distance data showed that nestmate recognition was strongly genetically influenced in F. pratensis. Received: 2 October 1997 / Accepted after revision: 10 January 1998  相似文献   
89.
多级模糊模式识别方法用于河流水质评价   总被引:4,自引:0,他引:4  
脱友才  邓云  王旭 《四川环境》2007,26(1):59-62
应用多级模糊模式识别模型进行水质量分类评价,克服了最大隶属度原则所不适用的地方,而且以相对隶属度、隶属函数为基础理论,使隶属度、隶属函数的计算更容易。建立了多级模糊模式识别模型,并应用于汾河水质分类评价中,应用结果表明,该方法合理、可行。  相似文献   
90.
ABSTRACT: Flood control operations are generally complex in nature, as they are often associated with a large quantity of uncertain factors in combination of noncommensurable criteria. It has been found that the use of fuzzy set theory coupled with multicriterion decision making (MCDM) methods is very promising. In this paper, a multicriterion fuzzy recognition model is established for flood control operations. A subjective preference and iterative weights method is proposed for weight assessment. First, an initial solution of criteria weights, which is directly analyzed from the selected alternatives, is obtained by using the proposed fuzzy recognition model. Then, according to their knowledge related to real time flood operations, operators may modify the initial weights if necessary. When the relative membership grades of alternatives belonging to all rankings are fixed, a defuzzification equation is used to calculate the rank feature value vector. Based on the rank feature value vector, one can evaluate the alternative set. Two flood operation cases are provided to illustrate the application of the proposed model. With the incorporation of the operator's knowledge related to flood operations, the proposed model is flexible in giving weights and realizes more practical flood control operations.  相似文献   
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