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31.
Monitoring is an important and costly activity in resource management problems such as containing invasive species, protecting endangered species, preventing soil erosion, and regulating contracts for environmental services. Recent studies have viewed optimal monitoring as a Partially Observable Markov Decision Process (POMDP), which provides a framework for sequential decision making under stochastic resource dynamics and uncertainty about the resource state. We present an overview of the POMDP framework and its applications to resource monitoring. We discuss the concept of the information content provided by monitoring systems and illustrate how information content affects optimal monitoring strategies. Finally, we demonstrate how the timing of monitoring in relation to resource treatment and transition can have substantial effects on optimal monitoring strategies.  相似文献   
32.
焦晨 《价值工程》2015,(1):216-217
本文分析了高职院校环境监测实践教学中存在的问题,从实践参与教学模式、实践教学方法及考核、评价方式等方面进行了一系列的探索和尝试。  相似文献   
33.
By relaxing the common efficiency wage assumption of exogenous shirking detection probabilities, we demonstrate how standards and efficiency wages are related. In a more general setting where the probability of detection depends upon the equilibrium effort level of non‐shirkers, we show that the uniformly positive (negative) supply‐side relationship between wages (unemployment insurance) and effort is no longer guaranteed. Profit maximization on the part of the firm, however, ensures that effort will depend positively (negatively) on wages (unemployment insurance) in equilibrium.  相似文献   
34.
王建明 《价值工程》2014,(22):282-283
本论文通过对南京化工职业技术学院教学质量监控和保障体系的研究、构建与实施,并通过网络信息技术使体系的运行更顺利、便捷和高效,增强了教学质量监控和保障体系的针对性、可操作性,做到保障有方向、投入有重点、建设有力度、完善有策略,确保教学质量保障建设有理、有据、有序进行。  相似文献   
35.
We study the effects of police monitoring on crime. We exploit detailed information on the location and date of installation of police-monitored surveillance cameras, coupled with data at the street-segment level on all reported crimes in the city of Montevideo, Uruguay. We find that the introduction of police-monitored surveillance cameras reduces crime by about 20 percent in monitored areas relative to a pure control group located outside the city. We also explore potential displacement effects, and we do not find evidence of such effects.  相似文献   
36.
The analysis of the build-up of risks in emerging economies have traditionally been scarce and focused mostly on external risks, despite the recent substantial development of their financial system. This paper builds an index of financial vulnerabilities tailored to emerging economies, grouping 32 indicators around four poles: valuation and risk appetite, imbalances in the non-financial sector, financial sector vulnerabilities, and global vulnerabilities. It adopts a model-free approach, purposely departing from early warning models or complex econometric constructs, and rely on data made already available by international organisations. Our index of financial vulnerabilities enables a granular mapping of where risk originates and how it spreads to other parts of the financial system. Using various data visualisation tools and benefitting from the flexibility of our index’s methodology, we are able build a narrative of the evolution of financial stability in emerging economies from 2005 to 2015. Finally, we also discuss the relation between our index and both the business cycle (proxied by GDP) and the credit cycle (proxied by the credit-to-GDP gap).  相似文献   
37.
The extant literature shows that institutional investors engage in corporate governance to enhance a firm's long‐term value. Measuring firm performance using the F‐Score, we examine the persistent monitoring role of institutional investors and identify the financial aspects of a firm that institutional monitoring improves. We find strong evidence that long‐term institutions with large shareholdings consistently improve a firm's F‐Score and that such activity occurs primarily through the enhancement of the firm's operating efficiency. Other institutions reduce a firm's F‐Score. Moreover, we find evidence that, while monitoring institutions improve a firm's financial health, transient (followed by non‐transient) institutions trade on this information.  相似文献   
38.
We examine the relation between intra-group trust and monitoring in a patriarchal society, and how this relation affects workgroup performance. Data were collected from 352 women who were members of 72 female workgroups in Addis Ababa by means of field experiments and a survey. The data are analyzed using multiple mediation analysis. We find that intra-group trust needs time to develop, and that trust is higher in workgroups with more monitoring. The positive relation between monitoring and trust might be explained by women’s ambition to overcome disempowerment and negative gender stereotypes. The results also indicate positive effects of intra-group trust and monitoring on workgroup performance, and that the effect of monitoring runs through its relation with trust. The last finding stresses the importance of monitoring for developing intra-group trust in these female workgroups.  相似文献   
39.
Due to the advantages of being able to function under harsh environmental conditions and serving as a distributed condition information source in a networked monitoring system, the fibre Bragg grating (FBG) sensor network has attracted considerable attention for equipment online condition monitoring. To provide an overall conditional view of the mechanical equipment operation, a networked service-oriented condition monitoring framework based on FBG sensing is proposed, together with an intelligent matching method for supporting monitoring service management. In the novel framework, three classes of progressive service matching approaches, including service-chain knowledge database service matching, multi-objective constrained service matching and workflow-driven human-interactive service matching, are developed and integrated with an enhanced particle swarm optimisation (PSO) algorithm as well as a workflow-driven mechanism. Moreover, the manufacturing domain ontology, FBG sensor network structure and monitoring object are considered to facilitate the automatic matching of condition monitoring services to overcome the limitations of traditional service processing methods. The experimental results demonstrate that FBG monitoring services can be selected intelligently, and the developed condition monitoring system can be re-built rapidly as new equipment joins the framework. The effectiveness of the service matching method is also verified by implementing a prototype system together with its performance analysis.  相似文献   
40.
The present study aimed to investigate the viable eumycetes population of indoor air sampled in a mass catering plant that produces up to 1200 meals per day. The combination of a culture-dependent and -independent approach applied in the food-processing environment was efficient for the identification of airborne eumycetes. Penicillum, Cladosporium and Alternaria were the dominant genera, while Thysanophora, Aspergillus, Rhizopus, Annulohypoxylon, Arthrinium, Aureobasidium and Trametes were found to be in minority. The size and composition of the eumycetes population found in this study do not raise specific concerns. Nevertheless, a quantitative and qualitative monitoring of these bioaerosol should be included in the progress and criticality reports of the HACCP system in the catering services where eumycetes can pose different risks, such as worsening of the overall quality of meals and/or of the work environment. Indeed, these reports are a useful tool in the preventive HACCP approach, provided that an adequate frequency of sampling is planned in order to quicken the pre-warning process.  相似文献   
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