一种核安全级柴油发电机组

介绍一种核安全级柴油发电机组,这种柴油发电机组应用于核电站应急备用电力系统。其最大特点是结构上强大的抗地震功能。在地震发生时或(和)地震后机组均能启动并满足对它的基本性能要求。     

自然数中整除关系的一个结果

有限偏序集上满足一定条件的组合计数问题,一直使人们很感兴趣。{1,2,…,2几}这2件个自然数 中选取件个,使其中任两个不具有整除关系,本文讨论了哪些数可以选取,哪些数不能选取,并得 到了所允许选取的最小数及所有不同选取种数的两个简捷的计数公式。      

用迭代自组织数据分析技术A(ISODATA)对零件进行模糊分类

本文将机械零件的GT分类编码视为模糊样品集,进行分类成组。给出 了模糊数学模型,用IsODATA模糊聚类方法进行求解,程序运行的结 果表明:比普通聚类法运行速度快,结果更切合客观实际。      

一种新的区间值模糊集推理方法

在两向量相似度的基础上, 定义了两个区间值模糊集在一点处相似度, 然后在此基础上提出了一种新的模糊推理方法--区间值模糊集相似度推理方法.并且对该种方法的还原性进行了讨论,给出了满足还原算法的条件.     

Not bored yet - Revisiting respondent fatigue in stated choice experiments

Stated choice surveys are used extensively in the study of choice behaviour across many different areas of research, notably in transport. One of their main characteristics in comparison with most types of revealed preference (RP) surveys is the ability to capture behaviour by the same respondent under varying choice scenarios. While this ability to capture multiple choices is generally seen as an advantage, there is a certain amount of unease about survey length. The precise definition about what constitutes a large number of choice tasks however varies across disciplines, and it is not uncommon to see surveys with up to twenty tasks per respondent in some areas. The argument against this practice has always been one of reducing respondent engagement, which could be interpreted as a result of fatigue or boredom, with frequent reference to the findings of Bradley and Daly (1994) who showed a significant drop in utility scale, i.e. an increase in error, as a respondent moved from one choice experiment to the next, an effect they related to respondent fatigue. While the work by Bradley and Daly has become a standard reference in this context, it should be recognised that not only was the fatigue part of the work based on a single dataset, but the state-of-the-art and the state-of-practice in stated choice survey design and implementation has moved on significantly since their study. In this paper, we review other literature and present a more comprehensive study investigating evidence of respondent fatigue across a larger number of different surveys. Using a comprehensive testing framework employing both Logit and mixed Logit structures, we provide strong evidence that the concerns about fatigue in the literature are possibly overstated, with no clear decreasing trend in scale across choice tasks in any of our studies. For the data sets tested, we find that accommodating any scale heterogeneity has little or no impact on substantive model results, that the role of constants generally decreases as the survey progresses, and that there is evidence of significant attribute level (as opposed to scale) heterogeneity across choice tasks.     

粗糙集与神经网络在发动机故障诊断中的融合应用

电喷发动机运行的状态信息众多而复杂,故障与状态信息的关系模糊而不确定,如何从复杂的多元信息中获取有用部分并加以利用是电喷发动机故障诊断的关键.本文应用粗糙集理论对冗余信息进行约简,得到更为简明的诊断规则,将约简结果与神经网络相结合,建立了故障诊断系统.网络的训练对比结果表明,粗糙集理论的约简处理简化了神经网络结构,提高了网络的训练效率;通过实例验证了粗糙集理论与神经网络相结合进行电喷发动机故障诊断的可行性.     

静音发电机组在野战车载系统中的应用技术研究

简要介绍了静音发电机组的外军应用情况及技术特点,提出了研制过程中涉及的关键技术及其方案。     

基于粗糙集与支持向量机的推土机故障诊断

提出了一种基于粗糙集理论和支持向量机算法的推土机发动机故障诊断方法。首先利用粗糙集理论对故障诊断决策系统进行约简,消除样本噪声和冗余,然后在此基础上设计支持向量机多分类器,进行故障检测分类。这样,可以有效减小SVM训练的数据,加快多分类器的处理速度。实验结果显示它能提高故障诊断的准确性和效率。     

A robust approach for road users classification using the motion cues

Video monitoring of traffic is a common practice in major cities. The data generated by video monitoring has practical uses such as traffic analysis for city planning. However, the usefulness of video monitoring of traffic is limited unless there is also a reliable way to automatically classify road users. This paper presents an automated method of road users’ classification into vehicles, cyclists, and pedestrians by using their motion cues. In this method, the movement of road users was captured on sequences of video frames. The videos were analysed using a feature-based tracking system, which has returned the tracks of road users. The separate pieces of information gained from these tracks are hereafter called Classifiers. There are nineteen classifiers included in this method. The classifiers’ values were assessed and integrated into a fuzzy membership framework, which in turn required prior configurations to be available. This led to the final classification of road users. The performance of this method demonstrated promising results. An important contribution of this paper is the creation of a robust approach that can integrate different classifiers using fuzzy membership framework. The developed method also uses parametric classifiers, which do not depend on the specific geometry or traffic operation of the intersection. This is a key advantage because it enables transferability and improves the practicality and usefulness of the method.