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1.
程欣 《水利经济》2018,36(6):48-52
以城市自来水水质事故致因为研究视角,首先识别供水水质风险因素,并从单、双及多因素角度分析供水水质风险因素间的耦合关系,再借助N-K模型对2008—2017年全国所发生的362起城市重大供水水质风险耦合度进行度量。结果表明:城市自来水供应动态系统中,水质风险率随着参与耦合的风险因素的增多而增加;管理因素风险是水质风险的内因,风险管控是规避水质风险的关键;环境因素风险对水质事故的发生起推动作用。  相似文献   
2.
Abstract

This paper analyzes the use and effectiveness of patents and trade secrets designed to protect innovation. While previous studies have usually considered patents and trade secrets as substitutes for one another, we investigate to what extent and in what situations the two protection methods are used jointly. We identify protection strategies for single innovation firms and hence overcome the assignment problem of existing empirical studies, that is, whether firms using both protection methods do so for the same innovation or for different innovations. Employing firm panel data from Germany, we find fairly few differences between the determinants for choosing secrecy and patenting. Single innovators that combine both strategies, 39% of the group, tend to aim at a higher level of innovation and act in a more uncertain technological environment. Firms combining both protection methods yield significantly higher sales with new-to-market innovations, providing some evidence for a complementarity of the two protection methods.  相似文献   
3.
It seems intuitively obvious that firms in supply chains may have more to gain than to lose from learning to cooperate; but it is now more than two decades since Poirier [1999. Advanced Supply Chain Management. San Francisco, CA: Barrett-Koehler] and others called for cooperation in order to capture mutual gains in supply networks and even now ‘cooperation is neither common nor easy’. The simple fact is that not only are supply chains exceptionally complex but so too is the ‘process of cooperating’ – often in the context of antitrust legislation and competition policy. This paper argues that there is a critical need to rethink the principles and processes of cooperation within the broader framework of the competitive behaviour of firms and business strategy. Particularly, it suggests that the relatively recent thinking of Greenwald and Kahn [2005 Greenwald, B., and J. Kahn. 2005. Competition Demystified A Radically Simplified Approach to Business Strategy. New York, NY: Portfolio, The Penguin Group. [Google Scholar]. Competition Demystified A Radically Simplified Approach to Business Strategy. New York, NY: Portfolio, The Penguin Group] in their ‘radically simplified approach to business strategy’ offers sound conceptual insights into cooperation and cooperative strategies for firms not only in markets but also in chains. Furthermore, it notes that the analytical framework for cooperation and cooperative strategies which the authors develop is far removed from the notion of cooperation as ‘commitment and trust and shared thinking’ and from ‘buyer/seller reciprocity’ and ‘collaborative attitudes’ which tend to underwrite much contemporary thinking and research. The paper also argues that the Greenwald and Kahn framework – its single intelligence model of cooperation and cooperative strategies – resonates with real-world relevance, at least for particular supply chains. The paper focuses attention on research into globally significant export coal chains from major east coast Australian ports and in brief case studies finds substantial alignment between concept and practice.  相似文献   
4.
李群芳 《北方经贸》2007,(8):134-135
目前,我国许多城市土地使用过于单一,损害居民利益,严重妨碍城市宜居。本文从宜居城市概念和评价标准入手,提出宜居城市的核心思想——以人为本,分析土地使用过于单一给居民带来的负面影响,论述土地适度混用的必要性,并提出了建设性意见。  相似文献   
5.
为降低铁路单线隧道接触网弓形腕臂预配施工难度,论文研究了一种接触网弓形腕臂预配平台,结合单线隧道内弓形腕臂数据精测技术及计算软件,精确测量预配,保证弓形腕臂的安装精度和质量,使弓形腕臂在现场施工中一次成优。论文结合实际,就某铁路单线隧道接触网弓形腕臂预配平台作具体分析。  相似文献   
6.
To increase the relevance of logistics and supply chain academic research, this paper recommends the development and testing of middle‐range theory and practice‐level theory. Yet, there are a number of research issues that arise when academic researchers test middle‐range and practice‐level theory, both in measuring constructs and in testing theoretical relationships between constructs. Concerning the measurement of constructs, this paper recommends that academic researchers pay more attention to content validity and undertake rigorous processes to ensure content validity. In addition, academic researchers need to more explicitly define constructs as either reflective or formative. If the construct is defined as formative, then the traditional statistical approaches to validate these measurement scales are not recommended. The appropriate use of employing single‐item measures for concrete constructs is discussed. In regard to conducting hypothesis tests, research issues associated with multicollinearity and omitted variable bias are discussed. Relative weight analysis is ideal for testing theoretical models and research hypotheses when survey data are obtained, multicollinearity is present, and there are a large number of independent variables predicting a dependent variable. Thus, relative weight analysis is ideal for testing research hypotheses in logistics and supply chain management.  相似文献   
7.
费平  赵秀  金海玉 《价值工程》2015,(5):307-309
头道桥糜棱岩是以塑性变形为主的韧性剪切带,形成了糜棱岩、碎裂岩系列,该糜棱岩带中糜棱岩的原岩均为花岗岩,该韧性剪切带中的糜棱岩化花岗岩、花岗质初糜棱岩以及花岗质糜棱岩的单矿物化学特征和岩石地球化学特征与岩石变形强度增大和退变质作用增强有着密切的关联,他们都表现出了一定的规律性。  相似文献   
8.
通过对全封闭单托辊输送机的创新的优化设计,使得此设备在原有的设计基础上,在清扫器、单托辊、靴型料斗、头部耐磨衬板和轴承测温系统等方面进行进一步优化,使之在使用方面更加可靠,维护保养更加方便,实现了该设备的使用性能的又一次飞跃。  相似文献   
9.
Abstract

The paper presents a reform proposal for the operations of the European Central Bank (ECB) whose purpose is to create a common set of risk-free assets for financial institutions operating in the euro area (EA), which is the necessary condition for having a single internal financial market. The proposal does not require the introduction of changes in the existing European Union treaties. The effects of this reform on the debt dynamic of EA member countries permit a revision of the existing fiscal rules. With the help of some simulations, it is shown that maintaining compliance with the European treaties, the reform of the ECB operations and revised fiscal rules would transform the current fiscal deflationary stance into a reflationary one. Some implications for aggregate demand and growth for the EA are briefly discussed.  相似文献   
10.
This study uses aggregated municipality data, for the years 2001–2009, to explore whether direct payments to farmers affect agricultural employment in Swedish municipalities. The decoupling reform in 2005 included a new grassland support payment accompanied by management obligations that had unexpectedly high redistributive consequences as it greatly increased common agricultural policy payments to municipalities with large areas of grassland. In some municipalities, total payments more than doubled. Thus, since the reform seems exogenous to the behaviour of farmers and the regional economy, the reform can be used to identify a subsidy effect. We find that a permanent increase in agricultural employment can be attributed to the new grassland support. Our results indicate that the grassland support generates an additional job at a cost of SEK 250,000, relative to the average agricultural wage of SEK 333,000. However, the subsidy effect is largely keeping jobs in agriculture, i.e. the grassland support may be slowing down the process of structural change in grassland regions.  相似文献   
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