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61.
This study investigated the geographic distribution of suicide and railway suicide in Belgium over 2008--2013 on local (i.e., district or arrondissement) level. There were differences in the regional distribution of suicide and railway suicides in Belgium over the study period. Principal component analysis identified three groups of correlations among population variables and socio-economic indicators, such as population density, unemployment, and age group distribution, on two components that helped explaining the variance of railway suicide at a local (arrondissement) level. This information is of particular importance to prevent suicides in high-risk areas on the Belgian railway network.  相似文献   
62.
Following recent advances in the non‐parametric realized volatility approach, we separately measure the discontinuous jump part of the quadratic variation process for individual stocks and incorporate it into heterogeneous autoregressive volatility models. We analyse the distributional properties of the jump measures vis‐à‐vis the corresponding realized volatility ones, and compare them to those of aggregate US market index series. We also demonstrate important gains in the forecasting accuracy of high‐frequency volatility models.  相似文献   
63.
铁路货运站是铁路货物运输的起点和终点,大力提升铁路货运站适应能力是顺利实施铁路货运改革的重要基础。文章统筹考虑全国主要货运站存在的主要问题,从运转设备能力和货运设施能力两个层面分析铁路货运站的适应性问题即货运站适应能力,提出具体的提升铁路货运站适应能力的对策及建议。  相似文献   
64.
High‐speed rail (HSR) has led to a transportation revolution in China. This paper uses the county‐level panel data of China’s Yangtze River Delta to investigate the effect of HSR connection on local economy. To address the issue of endogenous HSR route placement, we use a straight‐line strategy to construct potential HSR connection variables as instrumental variables of the actual HSR connection. Both the difference‐in‐differences and instrumental variable methods show that HSR connection impedes local economy, especially in peripheral regions. The impediment effect is channeled through population reallocation from peripheral to core areas and the restructuring of industries.  相似文献   
65.
在复杂地质条件下,需要加强高面板堆石坝工程质量管控工作,严格地按照国家出台的质量安全责任规章,提高建设质量。论文主要围绕高面板堆石坝工程、工程质量控制措施两个方面进行探讨,确保混凝土面板堆石坝的施工质量。  相似文献   
66.
文中探讨如何运用SWOT战略分析方法确定乌海地区铁路运输业目前面临的重要外部机会和威胁,以及内部存在的主要优势和劣势,并运用SWOT定量分析模型,对乌海铁路运输业发展做出科学评估,在此基础上明确乌海铁路货运发展战略定位,研究并提出相应的发展策略,从而充分发挥该市的自身优势。  相似文献   
67.
王海 《价值工程》2014,(25):134-135
在一些基础性开发的建设过程中存在许多地质灾害问题,其中高边坡滑坡现象尤为严重。本文针对高边坡滑坡现象的类型、成因等进行了分析,并提出了相应的解决措施。  相似文献   
68.
To achieve sustainable development, companies are increasingly putting an emphasis on the creation and the promotion of environmentally sustainable innovations. Environmentally sustainable innovation often involves a significant shift in a new strategic direction. This paper studies this shift from a dynamic capabilities perspective and aims to identify the microfoundations of science‐based companies' dynamic capabilities for high‐tech environmentally sustainable innovations. It investigates the development of high‐tech environmentally sustainable innovations in two distinctive science‐based companies. To scholars, this study provides an in‐depth process analysis, over time, of how and why microfoundations of dynamic capabilities influence the development of a science‐based company's high‐tech environmentally sustainable innovations. To practitioners in science‐based firms, this process study can function as a frame of reference, enabling the tailoring of a strategy for high‐tech environmentally sustainable innovation.  相似文献   
69.
This paper examines the development of multimodal passenger rail hubs as part of the high-speed rail (HSR) network in the People’s Republic of China (PRC). The instrumental, attitudinal and affective experience of the journey through the interchange is assessed from the user perspective. Surveys are used from three HSR stations: Beijing South, Chengdu East and Suzhou North (N = 150), representing three types of HSR stations, i.e. national capital, regional capital and sub-regional city. ‘Expected’ and ‘realised’ facilities are compared – with the difference representing the ‘disgruntlement’ factor (after Stradling et al., 2007).The unprecedented urbanisation process currently being witnessed in the PRC, together with the rapid development of the HSR network and associated multimodal interchanges, offers much opportunity to develop a leading-edge public transport system and urban development predicated on the use of public transport. Although the importance of intermodal interchange hubs is being increasingly recognised, the journey experience through the interchange often remains poor, with problems including Wi-Fi availability, waiting and seating, the availability of door-to-door ticketing, crowdedness, access to the hub, time of travel through and waiting in the hub. MANOVA analysis and factorial (three way) MANOVA analysis are used to explore the differences between intermodal hubs, with many instrumental and particularly attitudinal and affective factors being significantly influenced by location.  相似文献   
70.
王树友 《价值工程》2015,(13):98-100
本文通过试验分析特细砂粒径,不同材质的特细砂的基本物理材性,采用现代混凝土配合比设计理念,研究了特细砂混凝土配合比的设计原则。通过分析砂率含量、用水量、高效外加剂对特细砂高性能混凝土在工作性和力学性能上的影响,确定砂率含量的范围;通过对特细河砂和天然特细山砂混凝土性能的对比试验,结果表明细砂完全可以替代天然中粗砂配制高性能高强度、高流动性泵送混凝土。  相似文献   
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