Model comparison of linear and nonlinear Bayesian structural equation models with dichotomous data

In this article, dichotomous variables are used to compare between linear and nonlinear Bayesian structural equation models. Gibbs sampling method is applied for estimation and model comparison. Statistical inferences that involve estimation of parameters and their standard deviations and residuals analysis for testing the selected model are discussed. Hidden continuous normal distribution (censored normal distribution) is used to solve the problem of dichotomous variables. The proposed procedure is illustrated by a simulation data obtained from R program. Analyses are done by using R2WinBUGS package in R-program.     

The effect of different data structures,sample sizes on model fit measures

In this study, our aim was to investigate the changes of different data structures and different sample sizes on the structural equation modeling and the influence of these factors on the model fit measures. Examining the created structural equation modeling under different data structures and sample sizes, the evaluation of model fit measures were performed with a simulation study. As a result of the simulation study, optimization and negative variance estimation problems have been encountered depending on the sample size and changing correlations. It was observed that these problems disappeared either by increasing the sample size or the correlations between the variables in factor. For upcoming studies, the choice of RMSEA and IFI model fit measures can be suggested in all sample sizes and the correlation values for data sets are ensured the multivariate normal distribution assumption.     

Effects of key enabling technologies for seru production on sustainable performance

Demand uncertainty, economic globalization, and environmental deterioration force factories to innovate their manufacturing systems for achieving sustainable performance. Seru production, which is the latest manufacturing mode developed in Japan, attracts broad attention from both academia and practitioners. The overwhelming majority of existing works on seru production focus on economic performance unilaterally, while neglecting the environmental and social performance. This paper investigates the effects of key enabling technologies for seru production on sustainable performance. Firstly, four key enabling technologies for seru production are identified through systematic review, and an evaluation indicator system of sustainable performance in the context of seru production is developed. Then, the hypotheses about the effects of the identified key enabling technologies for seru production on sustainable performance are proposed on the basis of previous research achievements, theoretical analysis, and practical observations. Finally, the hypotheses are tested through structural equation modeling. Except for two hypotheses which are not supported and one which is indirectly supported, all other hypotheses are verified. The research results show that the four key enabling technologies for seru production have different effects on the three dimensions of sustainable performance. The achievements of this work are of significance to improve the comprehensive understanding of seru production, as well as to develop practical methods to implement sustainable operations.     

城市边缘地带地质灾害风险的形成与分配——以L市H社区的地质灾害为例

在风险社会中,既存在着普遍性风险,也存在着特殊性风险,考察特殊性风险的形成与分配应从微观层面入手。文章从风险社会学的角度研究L市边缘地带H社区的地质灾害风险。在梳理技术资料获取地质灾害风险形成的自然致灾因素之后,运用口头访谈方式直接从被访问者处获得一手资料,了解其个人生活史、进入社区的不同原因与方式、居住条件、生计方式等内容,探求直接或间接的影响该区域地质灾害风险形成的社会因素,最终得出该风险的分配原则:社会地位直接决定其风险地位。     

Residential mobility and the spatial dispersion of personal networks: Effects on social support

Using a representative national sample of personal networks, this article explores how the spatial dispersion of networks, residential mobility and social support are linked. Three issues will be addressed here. Firstly, how is the spatial dispersion of personal networks related to individuals’ social characteristics, network composition and residential mobility? Secondly, how do the spatial dispersion of networks, residential mobility and their combined effect influence the number and (thirdly) the structure of emotional support ties? Results showed that the extent of the support was affected neither by the geographical distribution of the networks nor by residential mobility. Living far from one's birthplace, however, exerted two distinct, and opposite effects on the support network structure. On the one hand, mobility led to high spatial dispersion of personal contacts, which in turn favored a sparsely knit network centered around the mobile individual. On the other hand, by controlling for the effect of distance between the contacts, we found that individuals that cited long-distance ties tended to be part of more transitive support networks than those that cited local ties. We interpreted the latter effect as evidence that transitive ties may survive greater spatial distances than intransitive ones. These findings are discussed in view of spatial mobility and social network research.     

LC滤波器设计的优化解析公式

给出了改进的Chebyshev和Butterworth低通原型LC滤波器的解析设计公式.此公式充分利用阶数取整带来的余量,在不改变滤波器阶数的前提下减小了通带波动,极大地方便了集成滤波器的实现.给出了集成有源高通滤波器设计实例,验证了改进的Chebyshev和Butterworth低通原型LC滤波器解析设计公式的有效性.     

城市空间关系问题研究——以黄冈与武汉城市圈内周边城市空间关系为例

城市化的快速发展使得城市空间关系不断变化,如何准确界定城市空间关系对城市战略选择至关重要。本文在总结前人对城市空间关系研究的基础上,将城市空间关系分为依附型、竞争型、共生型、异质型四种。进而在此基础上以黄冈为案例,研究黄冈与武汉城市圈内周边城市的关系,并提出黄冈的定位和发展战略。     

90年代以来甘肃省人力资本水平空间差异探讨

随着知识生产与创造的高素质科技劳动者逐步成为一个地区能否吸引现代经济活动的关键．人力资本在区域经济增长中越来越受到人们的关注。文章从时间和空间两方面入手．探讨了90年代以来甘肃省人力资本水平的空间差异及其变化状况。结果表明：甘肃省区域人力资本水平得到明显提高。人力资本水平的地理空间格局由1990年的中部高、西北和东南部低的“凸”字形分布渐渐转向2000年的中西北部高。而东南部低的倾斜式分布：区域人力资本水平差异仍然较大,其增长幅度的区域差异也十分显著。文章还就人力资本差异的形成机制进行了探讨,并提出了促使区域人力资本可持续发展的相关建议和对策。     

CO-OFDM系统中基于线性预处理的新相位噪声抑制算法

针对相干光正交频分复用（coherent optical orthogonal frequency division multiplexing,CO-OFDM）系统中相位噪声引起的载波间干扰（inter-carrier interference,ICI）问题,提出了一种基于线性预处理的新判决反馈相位噪声抑制算法。该新算法改进了线性预处理部分,利用循环前缀与OFDM符号固有的相关性,在时域进行简单的线性组合运算,充分利用了OFDM符号中冗余信息。仿真分析表明,在激光器线宽为200 kHz且误码率（bit error rate, BER）为10－4时,与判决反馈相位噪声抑制算法和一次迭代的判决反馈相位噪声抑制算法相比,该新算法BER曲线的信噪比（signal to noise ratio,SNR）分别改善了3 dB和1 dB,有效地降低由ICI引起的错误平层。     

城市多元生鲜市场空间格局的演变及其相互关联——以昆明主城区为例

生鲜市场关系到民生、城乡经济联系和就业等问题,孤立地研究某一类型的生鲜市场具有片面性,不利于理解整个城市的生鲜市场功能和全局管理。通过对昆明市主城区各种生鲜市场实地调查和问卷,运用ArcGIS空间叠加分析、核密度分析和统计分析等多种方法描述了该城市多元生鲜市场的空间格局的形成和演变,归纳不同生鲜市场的特征及其多元生鲜市场共存格局的原因,并对未来演变趋势进行分析,提出此消彼长的互动关联性对各主体所隐含的机遇和挑战,由此说明从地域视角开展的研究,能综合把握全局特征,以及各类型之间的彼此关联性,可弥补以往单一类型研究的不足,并对政府的相关决策进行讨论。