基于多特征量的D矩阵模型的建立与分析

针对基于单特征量的D矩阵模型会损失测试信号的大量信息的问题,提出了一种基于多特征量的可测性分析模型。首先,在研究D矩阵模型的基础上,对测试信号进行特征提取和多值编码,建立了基于多特征量的D矩阵模型。其次,基于信息熵制定诊断策略和生成故障诊断树,并对模型进行测试性分析,评估其诊断能力。结果表明,与单特征量的D矩阵模型相比,基于多特征量的D矩阵模型选用的测试点数和模糊组数小,故障隔离率高,诊断测试步骤数少,平均测试费用低。     

基于粒子群算法的数字微流控芯片在线测试路径优化

数字微流控生物芯片的稳定性和安全性在生化实验中具有很高的要求,为保证实验结果的准确,需要对芯片进行检测。通过分析芯片结构、实验液滴的路径,提出一种基于粒子群算法的针对数字微流控芯片灾难性故障在线测试路径优化方案。通过自适应调整算法惯性权值,设置算法的收敛速度因子和解的聚集程度因子,将收敛速度和局部解聚集程度可视化改进算法。增加液滴移动序列的交换机制,在芯片的约束条件下规划测试液滴的移动路径,从而缩短测试路径长度。仿真实验选择15×15阵列模型、7×11阵列模型、7×7阵列模型进行仿真实验,结果表明,该方案完成了对芯片的测试,提高了算法收敛速度,并有效缩短了测试路径,提高测试效率。     

基于迟滞阈值分割的瓶口缺陷检测方法

随着工业机器人和现代化工业的快速发展,人们对工业机器人的性能要求越来越高,为了提高工业生产的效率和产品的质量,智能、高速、高精度是工业机器人的必备要求。国内基于机器视觉的智能啤酒瓶口缺陷检测方法中,高速、高精度仍是一个亟待解决的问题。为此,提出了一种基于随机圆拟合评估的四圆周定位法,大大提高了瓶口检测区域的定位精度,并提出了基于投影特征的分区域磁滞阈值分割的智能瓶口缺陷检测方法。对采集的488幅灰度图像进行测试,检测正确率为99.4%,检测平均速度为38 ms,算法的检测速度快,检测精度高,可以很好地应用到高速、高精度的现代化工业机器人中。     

做好铁路施工材料试验检测 , 保障铁路工程施工建设质量

铁路交通运输与公路交通运输是我国经济发展的两大动脉,因此,铁路与公路工程建设是我国重要的基础性建设项目,其重要性不言而喻。在我国经济的迅猛发展中,铁路交通是一个主要动脉,铁路工程建设是一项重要的基础性项目,其质量在很大程度上关系着我国的经济发展状况。所以在铁路工程的施工中,要重视其施工质量。在严格把控施工建设质量的环节中,施工材料的试验检测是一个重要内容,要想建设出高质量的铁路工程,就要保证施工材料的质量。     

低能耗钢化玻璃产品认证介绍

低能耗钢化玻璃认证是由认证机构证明企业生产钢化玻璃过程中能源消耗符合相关标准或技术规范要求的合格评定活动。由第三方认证机构对钢化玻璃生产的能耗核查、测评、产品检验等进行技术评价。低能耗钢化玻璃认证可为绿色产品评价(建筑玻璃)提供技术支持,也可为钢化玻璃生产企业等相关方在采购钢化炉、改造钢化炉能耗评价效果方面提供科学、可信的依据。     

A Bayesian Network model for predicting cooling load of commercial buildings

Cooling load prediction is indispensable to many building energy saving strategies. In this paper, we proposed a new method for predicting the cooling load of commercial buildings. The proposed approach employs a Bayesian Network model to relate the cooling load to outdoor weather conditions and internal building activities. The proposed method is computationally efficient and implementable for use in real buildings, as it does not involve sophisticated mathematical theories. In this paper, we described the proposed method and demonstrated its use via a case study. In this case study, we considered three candidate models for cooling load prediction and they are the proposed Bayesian Network model, a Support Vector Machine model, and an Artificial Neural Network model. We trained the three models with fourteen different training data datasets, each of which had varying amounts and quality of data that were sampled on-site. The prediction results for a testing week shows that the Bayesian Network model achieves similar accuracy as the Support Vector Machine model but better accuracy than the Artificial Neural Network model. Notable in this comparison is that the training process of the Bayesian Network model is fifty-eight times faster than that of the Artificial Neural Network model. The results also suggest that all three models will have much larger prediction deviations if the testing data points are not covered by the training dataset for the studied case (The maximum absolute deviation of the predictions that are not covered by the training dataset can be up to seven times larger than that of the predictions covered by the training dataset). In addition, we also found the uncertainties in the weather forecast significantly affected the accuracy of the cooling load prediction for the studied case and the Support Vector Machine model was more sensitive to those uncertainties than the other two models.     

跳跃荷载作用下体育馆大跨预应力次梁楼盖振动模拟分析

以某小学体育馆为工程背景,通过ANSYS建立有限元模型,考虑不同跳跃频率、跳跃人数和跳跃次数的荷载作用,对大跨度预应力混凝土次梁楼盖结构进行竖向振动模拟分析,并进行现场实测,结果表明:修正半正弦平方荷载模型模拟单人跳跃荷载所得分析结果与实测值相对误差为12.98%,比较接近;多人同步跳跃所导致的楼盖竖向振动加速度随人数的增加而增加,近似呈正比关系;考虑多人跳跃难以严格同步,引入倍增因子对跳跃荷载模型进行修正,与实测值验证较为接近。     

Agglomeration,Differentiation and Creative Milieux: A Socioeconomic Analysis of Location Behaviour of Creative Enterprises in Shanghai

This paper presents an empirical study on the location choice of creative enterprises in Shanghai. It is suggested that categorical differences between different subsectors of creative industries are significant, especially with regard to a division between technology-intensive sectors and culture-related agencies. Creative enterprises from technology-intensive sectors such as architecture design and IT enterprises appear to differ greatly from cultural and fashion related agencies in location choice due to the disaggregated knowledge inputs involved in the production processes, as well as the divergences in market operation. Meanwhile, this study suggests that some location variables for creative industries (e.g. human capital and face-to-face contact) highlighted by West-based studies on the “creative class” are relevant in the case of Shanghai while other factors like sexual tolerance bear minor importance.     

WUDAPT项目：城市形式与功能信息的众包解决方案及其应用

面对全球城市气候研究中的数据鸿沟,一个城市气候领域的先锋研究小组提出了WUDAPT项目以克服获取城市数据的障碍。文章基于“众包”理念,从城市形式与功能信息收集的视角,介绍了WUDAPT项目的概念和数据分级,分析了城市尺度（0级）、街区与建筑尺度（1、2级）的数据收集与应用的研究进展。文章指出WUDAPT将促进基于城市气候视角的城市形态研究方法的重大转变,并探讨了其在气候敏感型城市设计与规划中的应用潜力。     

Q460高强钢螺栓连接承载性能试验研究

通过对20个Q460高强钢螺栓连接的静力拉伸试验,研究高强钢材料强度和螺栓布置方式对连接承载力和变形的影响。根据力平衡和变形协调条件建立方程,理论分析高强度钢材螺栓连接的受力性能,考察相关规范的适用性。结果表明：螺栓横向布置时,试件的承载力和变形随间距增大而增大;边距由1.5d0增大到2d0,端距由2d0增大到2.5d0时,试件极限承载力仅提高了0.78%和2.37%,说明达到标准构造取值后,边距和端距增大对连接的承载力影响甚微。螺栓纵向布置时,试件的承载力仅随边距增大呈线性增大趋势。钢板承压强度设计值取1.26fu,对于Q460高强度钢材其取值偏小。为国产高强度钢材螺栓连接的设计理论和方法提供了科学依据。