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521.
Organizations may fail to keep their commitments to their employees, at times leading to psychological contract violation. Although many victims of violation remain with their employer despite such adverse experiences, little research exists on their responses in the aftermath of violation. This paper develops a post‐violation model to explain systematically how violation victims respond to and cope with violation and the effects this process has on their subsequent psychological contract. Central to post‐violation are the victims' beliefs regarding the likelihood of violation resolution and the factors affecting it. The model specifies how the victim engages in a self‐regulation process that results in an array of potential psychological contract outcomes. Possible outcomes include reactivation of the original pre‐violation contract, the formation of a new contract that may be more or less attractive than the original, or a state of dissolution wherein the victim fails to form a functional psychological contract with the employer. The research and practical implications of this model are discussed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
522.
523.
ABSTRACTWhile bioinvasion was an issue of low political salience in Europe, a new regulation addressing it was adopted in 2014 with strong support. This article analyzes the making of the regulation as an intriguing case of policy expansion amid economic crisis. Based on theoretical literature on drivers of EU policy integration and policy dismantling, alternative plausible explanations are explored. Our main finding is that development of economic policy consensus among member states on trade-environment nexus was crucial for progress towards regulatory action. Policy consensus has been driven by a confluence of three domestic factors: trade liberalization, market disintegration, and changing ideas about the desirability of EU-level law, with the European Commission as policy entrepreneur. Low political salience has also had an important effect. It has increased the influence of transnational conservation alliances, which have played a significant catalytic role in building consensus by shifting consciousness to economic reward of policy action vs inaction, and bringing international models for legislative reform to the EU jurisdiction. 相似文献
524.
ABSTRACT In this paper, an artificial neural network-based control strategy is proposed for low voltage DC microgrid (LVDC microgrid) with a hybrid energy storage system (HESS) to improve power-sharing between battery and supercapacitor (SC) to suit the demand-generation imbalance, maintain state-of-charge (SOC) within boundaries and thereby to regulate the dc bus voltage. The conventional controller cannot track the SCs current rapidly with the high-frequency component that will place dynamic stress on the battery, further resulting in shorter battery life. The significant advantage is that in the proposed control strategy, redirections of unwaged battery currents to SCs for fast compensations enhance battery life span. The proposed control strategy effectiveness was investigated by simulations, including a comparison of overshoot/undershoot and settling time in dc bus voltage with a conventional control strategy. The results have been experimentally verified by hardware-in-loop (HIL) on a field-programmable gate array (FPGA)-based real-time simulator. 相似文献
525.
Bottom-Up Risk Regulation? How Nanotechnology Risk Knowledge Gaps Challenge Federal and State Environmental Agencies 总被引:1,自引:0,他引:1
Nanotechnologies have been called the "Next Industrial Revolution." At the same time, scientists are raising concerns about the potential health and environmental risks related to the nano-sized materials used in nanotechnologies. Analyses suggest that current U.S. federal regulatory structures are not likely to adequately address these risks in a proactive manner. Given these trends, the premise of this paper is that state and local-level agencies will likely deal with many "end-of-pipe" issues as nanomaterials enter environmental media without prior toxicity testing, federal standards, or emissions controls. In this paper we (1) briefly describe potential environmental risks and benefits related to emerging nanotechnologies; (2) outline the capacities of the Toxic Substances Control Act, the Clean Air Act, the Clean Water Act, and the Resources Conservation and Recovery Act to address potential nanotechnology risks, and how risk data gaps challenge these regulations; (3) outline some of the key data gaps that challenge state-level regulatory capacities to address nanotechnologies' potential risks, using Wisconsin as a case study; and (4) discuss advantages and disadvantages of state versus federal approaches to nanotechnology risk regulation. In summary, we suggest some ways government agencies can be better prepared to address nanotechnology risk knowledge gaps and risk management. 相似文献
526.
Helicid snails appear to regulate Pb more closely than other toxic metals, though it is reported as the least toxic. No regulatory mechanism has been described in animals, and the possible role of Mg in limiting Pb assimilation is examined here for the first time. Three populations of Cantareus aspersus were fed Pb and Ca with three levels of Mg for up to 64 days. Metal assimilation and production efficiency was calculated for each of 108 snails. Populations differed in their pattern of uptake but soft tissue Pb was unaffected by dietary Mg. The proportion of Pb assimilated did not change as soft tissue concentrations increased, indicating no specific regulatory mechanism. The daily addition of Pb to the soft tissues increases with growth rate suggesting uptake is instead some function of growth or cell turnover. Bioconcentration factors varied with time and are unreliable indicators of an evolved regulatory mechanism for Pb. 相似文献
527.
The loss of Pb from snail soft tissues may depend on the excretion of Ca, and involve the mobilization of shell Ca. Most sub-adults in three populations of Cantareus aspersus (syn. Cornu aspersum Müller) either failed to add, or lost, shell mass on a diet with 250 μg g−1 Pb. Their failure to mineralize shell extensions occurred irrespective of food consumed, time or dietary Mg. Budgets of metals for 36 individuals in each of two populations showed that Ca loss would account for the reduction in shell mass. Lead concentrations were higher in the reduced shells but this may be a consequence of their smaller mass, rather than its cause. In both populations shell reduction correlated with the total mass of Pb assimilated. Any shell growth may have been dependent on the initial Ca reserve in each snail. Differential movement of Mg, Pb and Ca occurred between the shell and soft tissues. 相似文献
528.
选取万元GDP能耗作为参考序列,将工业发展过程中的5种主要污染物作为比较序列,运用灰色关联分析方法定量研究了河南省18个城市的环境管制和不同污染物之间的灰色关联程度,并提出了一些富有针对性的政策建议:加强监管,切实查找固体废弃物的产生来源,努力提高废弃物综合利用水平。 相似文献
529.
解析电除尘烟温与粉尘特性的最佳结合点 总被引:2,自引:0,他引:2
分析了电除尘烟温对粉尘特性的影响,以及烟温对电除尘器效率的影响,从中找出烟温调节与粉尘特性的最佳结合点。利用烟温调节的理念,应用余热利用节能电除尘技术对电除尘器进行提效改造,通过实例证明,这既可扩大电除尘器适应性和提高电除尘效率、满足低排放要求,又可节省电煤消耗和降低电耗,具有环保与经济的双重效益。 相似文献
530.
在采场均压防灭火实验室模型模拟实验的基础上 ,总结了煤峪口矿现场实施火区的调压工艺技术。该技术包括利用调压气室平衡火区风压、提高工作面风压和堵塞地表裂隙 3项调压措施 ,其防灭火效果十分显著。在这 3项措施中 ,无论是工作面升压或气室调压失效 ,此时填堵裂隙工程则会发挥重要作用 相似文献