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31.
以高职院校学生实践能力评测为研究对象,提出由学校、企业和社会共同构建的评测指标体系,阐述评测方法,使用数据库和面向对象开发技术,介绍系统设计和实施的主要步骤,并针对系统应用中存在的问题提出改进意见.  相似文献   
32.
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   
33.
Through a critical case study of the crash of American Airlines Flight 587, this paper draws upon ‘the Social Shaping of Technology’ (SST) approach to offer a reconceptualisation of the technology‐push and market‐demand model for High‐Reliably Organisations (HROs), providing support for a third factor, called here a ‘safety‐pull’. A safety‐pull is defined as organisationally supported reflexivity in which technology innovators and frontline operators collaborate to consider the potential implications of adopting new technologies in HROs and the complex ways this change may impact human operators' work performance, often in risky and unanticipated ways. In contrast to accidents occurring solely as the result of individual operator error, analysing the safety‐pull provides a way to tease out the wide range of factors that can contribute to HRO failures and offers a new SST perspective through which to examine high‐risk operations.  相似文献   
34.
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   
35.
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   
36.
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   
37.
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   
38.
Without sustainable competitive advantage firms have limited economic reasons to exist and will decline. Competitive advantage concerns the factors which provide competitive strength. This paper is based upon the resource-based view which considers firm resources to be heterogeneous and which believes that firms only have a small bundle of core resources irrespective of their overall performance. This research establishes the role of 36 intangible resources for 49 Asian airlines across three business models: network airlines; low-cost subsidiaries from network airlines; and low-cost carriers. It uses the VRIN framework which examines whether resources are valuable, rare, inimitable, and non-substitutable. Research participants distribute points between their chosen seven resources according to their perceived role in firm performance. Resources which meet all four requirements of VRIN are considered core competences and sources of sustained advantage. Across all 49 Asian airlines, the top-three most important resources of advantage are slots, brand, and product/service reputation. While these core resources are predictable, they have not previously been proven within the context of airlines, let alone geographically and by airline model. Results show that the core bundle of resources vary for each model, which helps to explain the difference in performance across models, and that some resources which were expected to be high-ranking, such as organisational culture and customer focus, were not.  相似文献   
39.
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   
40.
夏伟健  金雷 《价值工程》2015,(13):159-162
本文根据高酸值原油腐蚀机理,分析了加工高酸值原油对常减压(高酸值原油脱酸装置)装置的腐蚀特点和重点腐蚀部位,并在此基础上提出了具体的防护措施:电脱盐、塔顶"三注"、高温缓蚀剂、腐蚀监测等,并重点介绍了本公司50万吨/年常减压装置的具体防腐措施,实践证明这些措施取得了较好的防腐效果,最后根据实践提出了可行的改进建议。  相似文献   
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