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61.
中国的水污染是一个非常严重的问题,为了控制水污染,对中国未来废水排放量进行准确预测具有十分重要的意义。从影响废水排放量的潜在变量中筛选出GDP、人均GDP和产业结构三个关键预测变量,采用1998—2017年中国省域数据和基于任务相关性的机器学习方法对各省份废水排放量趋势进行预测。实验结果表明,所建立的预测模型能够保持线性回归模型的可解释性,并获得较高的预测精度(RMSE、MAE和MAPE分别为0.0882、0.0643和0.5533)。预计全国年废水排放总量2025年最低将达到9081209万吨,最高9903864万吨;2030年最低将达到10864311万吨,最高13081922万吨。政府部门可根据预测结果制定废水减排计划和经济发展规划,在发展经济的同时维持生态环境的平衡。  相似文献   
62.
The concept of User Driven Prioritisation Process (UDPP) was introduced to give Airspace Users (AUs) more flexibility under demand-capacity imbalance. This paper presents two UDPP-DCB models, built on the UDPP principle, using the Selective Flight Protection (SFP) approach to minimize the total delay cost. AUs are enabled to adapt their operations in a more cost-efficient way in the presence of capacity constraints in airspace, optimizing their flights to keep the priorities track. Then, ATFM integrates the AUs’ decision to reassign the time slots and the preferred rerouting trajectories. Results suggest that the delay cost for AUs can be largely reduced through applying the UDPP-DCB models proposed in this paper, while allowing rerouting proves effective in reducing the system delay cost.  相似文献   
63.
While imperfect substitutability between native and immigrant workers is an important mechanism in estimating the wage effects of immigration, its empirical literature is concentrated on the context of only a few countries. Using occupation task-intensity data from a unique Korean data set, we demonstrate that relatively skilled native Korean workers respond to increased low-skilled immigration by pursuing jobs more intensive in communication and cognitive tasks. This native response is mainly pronounced in knowledge-intensive service sectors and leads to an improvement in average wages in these sectors. Our results support the general assumption that the labor market impact of immigration critically depends on whether native and immigrant workers are substitutes or complements in production.  相似文献   
64.
This study integrates recent advances in interdependence theory with the literature on commitment‐based HR practices. New research on interdependence theory suggests that differences, or asymmetries, in task dependence among organisational members can cause interests to diverge. Prior research has shown that this can negatively affect interpersonal relations, individual outcomes and team processes. However, these insights gained on the dyadic, individual and team levels of analysis have not yet been explored at the organisational level and, until now, no research had yet connected these advances in interdependence theory to the field of HRM research. Hence, the current study investigates (a) whether asymmetries in task dependence do (or do not) matter at the organisational level and affect organisational effectiveness, (b) why this relationship may work by assessing a key mediator, namely, trust climate and (c) if and how these relationships can be altered by commitment‐based HR practices. Our moderated‐mediation model was tested and fully supported by a multi‐source data set of 8,390 employees from 67 organisations.  相似文献   
65.
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   
66.
王庚 《价值工程》2015,(21):60-61
本文以新疆塔什店矿区一号矿井为例,阐述了总图专业对于煤炭矿井设计前期的重要性,并通过在矿井工业场地合理选址、矿井建设与城镇规划关系及矿井建设对社会影响度等方面分析,说明了总图专业参与矿井前期设计的必要性,以期望提高总图专业设计的水平。  相似文献   
67.
控制系统的实时任务能否在规定的时限内完成依赖于调度算法的好坏。首先给出控制系统中实时任务模型,包括实时周期任务和实时非周期任务;然后,在考虑优先级倒置和非周期任务的基础上,介绍一种静态优化调度算法(RMS);最后,对调度算法进行可调度性分析。  相似文献   
68.
以北京、上海、广州、深圳(以下简称北上广深)四个一线城市为例,利用面板数据,建立多指标创新能力综合评价指标体系,运用城市科技创新能力综合评价模型对四座城市的创新能力进行比较和评价。结果表明,四座城市整体创新能力都处于高位,而且一直保持提升态势,但具有明显的阶段性特征,增速不同,出现分化,各有优势和不足,深圳总体优势明显。据此,进一步提出四座城市在差异化发展的同时,应取长补短、相互学习,实现优势互补;采取多种举措确保企业作为创新主体的核心地位;提高产学研合作,加快科研成果转化,完善知识产权制度,建立政企研界之间协同创新的良性互动机制。  相似文献   
69.
The socialization literature has long recognized the important role of perceived insider status in facilitating newcomer adjustment, but knowledge on how to cultivate this desirable psychological state is limited. This study examines newcomer–supervisor exchange as an antecedent of perceived insider status of newcomers, which in turn facilitates their social adjustment and task mastery during organizational entry. We also explore incumbent support as a boundary condition for these effects. We conducted a survey study on 320 new employees and 92 supervisors in China. This study revealed that newcomer–supervisor exchange was related positively to newcomers’ perceived insider status, and perceived insider status mediated the positive relationships of newcomer–supervisor exchange with social adjustment and task mastery. In addition, incumbent support moderated the positive relationship between newcomer–supervisor exchange and perceived insider status, as well as the positive mediated relationships of newcomer–supervisor exchange with social adjustment and task mastery through perceived insider status. Specifically, these relationships were weaker when incumbent support was higher. Theoretical and practical implications were discussed.  相似文献   
70.
目标激励在现代管理中应用得非常广泛,目标的明确度和难度与绩效的关系是目标设置研究领域的重要课题.实验表明,有明确的目标和没有明确的目标对绩效水平的影响不显著;目标难度和绩效水平正相关,两者的关系曲线表现为逐渐上升的波浪型曲线.  相似文献   
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