悬臂式掘进机回转机构的分析与建模

基于悬臂式掘进机回转机构的结构特点,对其液压控制系统的运行原理展开分析,并结合假设条件建立液压元件的基本方程,通过机理建模最后得到了系统的传递函数,为实现掘进机自动控制提供了实用的简化模型。     

统计法规如何促进企业统计的发展

文章阐述了我国企业统计发展落后的原因,强调了统计法规在统计工作中的调整作用,提出强化中观层面的统计职能将促进企业统计的发展,并对统计法规如何促进企业统计的发展给出了建议。     

Dismantling terrorist networks: Evaluating strategic options using agent-based modeling

Dismantling dark networks remains a critical goal for the peace and security of our society. Terrorist networks are the most prominent instantiation of dark networks, and they are alive and well. Attempts to preemptively disrupt these networks and their activities have met with both success and failure. In this paper, we examine the impacts of four common strategies for dismantling terrorist networks. The four strategies are: leader-focused, grassroots, geographic, and random. Each of these strategies has associated pros and cons, and each has different impacts on the structure and capabilities of a terrorist network. Employing a computational experimentation methodology, we simulate a terrorist network and test the effects of each strategy on the resiliency of that network. In addition, we test scenarios in which the terrorist network has (or does not have) information about an impending attack. Our work takes a structural perspective to the challenge of addressing terrorist networks. Specifically, we show how various strategies impact the structure of the network in terms of its resiliency and capacity to carry out future attacks. This paper also provides a valuable overview of how to use agent-based modeling for the study of complex problems in the terrorism, conflict studies, and security study domains.     

小型水库除险加固工程溢洪道设计研究

在广西上思县念伦水库溢洪道除险加固设计中，对原破损的溢流面进行凿毛，另铺一层混凝土作底板，让新老混凝土用锚筋连接，联合受力，同时在原溢流面上凿槽铺设纵横塑料透水盲管，以降低底板扬压力。设计较大程度地降低了工程造价，满足了溢洪道的泄洪功能要求，实践证明是行之有效的。     

论电视艺术中的光线与造型

光线是电视艺术的基础,没有了光线也就没有了电视艺术。在电视艺术创作中只有充分认识光线的性质,了解直射光、散射光、顺光、侧光和逆光带来的不同视觉效果,才能充分发挥光线在表现时空、刻画人物、强化环境气氛中的造型作用,为电视艺术创作服务。     

A new methodology for the logistic analysis of evolutionary S-shaped processes: Application to historical time series and forecasting

A new multi-logistic methodology to analyze long range time series of evolutionary S-shaped processes is presented. It conceptually innovates over the traditional logistic approach. The ansatz includes computing the residuals to an optimized multi-logistic trend curve least squares fitted to the time-series data. The elements of the residuals series are checked for autocorrelations and once detected the residuals series is further analyzed to search for eventual presence of underlying periodic structures using a truncated Fourier sine series. The method foundations ensures both a universal applicability and a capacity to disclose the existence of active clocks that can be possibly traced to the driving motors of the evolutionary character of the time series, due to the responsiveness of corresponding process to the development of economic cycles. On associating these two views, it is found that the methodology has a strong potential to improve the quality of short-term forecasts. These findings have been put to test through applications of the methodology to studying the time evolution of two commodities of strong economic and social importance (corn and steel) and good results were consistently obtained for both the analytical and forecasting aspects.     

A multi-criteria assessment of tourist farm service quality

Farm tourism is a significant means of supplementing farmers' incomes. This paper presents a methodology for ranking tourist farms by using a multi-criteria model based on the qualitative multi-criteria modeling methodology, DEX, to assess service quality. The software tool DEXi was used to achieve this end. The model was then applied to seven tourist farms with data derived from questionnaires completed by tourist farm operators and guests. The results are shown as service quality assessments for individual farms. The potential of the model for assessing the farms is demonstrated with the aim of providing a comprehensive explanation and justification of the assessment technique. It also indicates potential improvements that farms can make through “what-if” analysis and visualization. Despite limitations, such as use of qualitative data only, the approach is proposed as being both appropriate and advantageous when compared with other means of ranking enterprises.     

纳米TiO_2的表面处理方法及改性效果表征

分析了纳米 TiO_2 的团聚与分散机理 ,介绍了纳米 Ti O_2 的表面处理方法及表面处理效果的表征方法。     

An empirical investigation of the antecedents and performance outcomes of export innovativeness

The present study develops and empirically tests a conceptual model of the organizational, strategic, and environmental drivers of export innovativeness. The relationship between export innovativeness and export performance is also examined. Using data collected from 168 small- and medium-sized direct exporters, we find that decentralization in decision making, export market orientation, information exchange and export market dynamism have a significant influence on exporting firms’ degree of innovativeness. Furthermore, export innovativeness has a significant positive effect on export performance. Several theoretical and managerial implications are derived from these findings. Directions for future research are also provided.     

Modeling defaults of companies in multi-stage supply chain networks

The interest in supply chain networks and their analysis as complex systems is rapidly growing. The physical approach to the topic draws on the concept of heterogenous interacting agents. The interaction among agents is considered as a repeated process of orders and production. The dynamics of production in the supply chain network which we observe is nonlinear due to the random failures in processes of orders and production. We introduce an agent-based model of a supply chain network which represents in more detail the real economic environment in which firms operate. We focus on the influence of local processes on the global economic behavior of the system and study how the proposed modifications change the general properties of the model. We observe collective bankruptcies of firms, which lead to self-emerging network structures. Our results give insight into the dynamics of default processes in supply chain networks, which have important implications both for risk managers and policy makers. Based on the simulations we show that agent-based modeling is a powerful tool for optimization of supply chain networks.