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排序方式: 共有211条查询结果,搜索用时 15 毫秒
1.
Students may choose to play drinking games not only for reasons related to alcohol consumption but also because of incentives related to other aspects of play (competition, fun, interpersonal dominance, etc.). College students (120 men and 167 women) completed measures of motives for playing (based on T. J. Johnson, S. Hamilton, & V. L. Sheets, 1999) and consequences of playing drinking games. Exploratory principal-components analysis identified 8 reasons for playing. Men and women differed in their endorsement of the factors. Motives for play directly predicted consequences of play independently of alcohol consumption. Specific motives predicted specific types of consequences. In multiple regression analyses, Conformity motives were negatively related to consequences and may represent a form of protective motive. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
为确保无线传感器网络(WSN)覆盖和连通性最大化以及能量消耗最小化的有效监测,提出一种基于多目标生物习性激励(MOBHI)的传感器节点部署算法。首先,将传感器节点的区域(领地)根据诸如最大覆盖、最大连通性和最小能耗等多个目标,基于领地捕食者气味标记行为进行标记,并模仿气味匹配识别其监测的位置;其次,对多个目标的优化问题应用非受控Pareto最优,将其分解为多个单目标优化子问题并同时对它们进行优化,得到所需目标的解。仿真实验结果表明,本文提出算法在网络覆盖、连通性和能耗等性能指标方面都优于其他传感器节点部署的多目标和单目标优化算法。 相似文献
3.
Impact of a simple load balancing approach and an incentive-based scheme on MANET performance 总被引:1,自引:0,他引:1
Most reactive mobile ad hoc network (MANET) routing protocols such as AODV and DSR do not perform search for new routes until the network topology changes. But, low node mobility does not affect the MANET connectivity and the same routes may be used for a long time. This may cause concentration of traffic on few mobile stations (MSs), which results in congestion and hence longer end-to-end delay. In addition, continuous use of MSs may cause their battery power to get exhausted rapidly. Expiration of MS energy causes disruption of connections traversing through the MSs and could generate many simultaneous new routing requests. Therefore, we propose a load balancing approach called Simple Load Balancing Approach (SLBA), which can be transparently added to any current reactive routing protocol such as AODV and DSR. SLBA minimizes the traffic concentration by allowing each MS to drop RREQ or to give up packet forwarding depending on its own traffic load. Meanwhile, MSs may deliberately give up forwarding packets to save their own energy. For encouraging MSs to volunteer in forwarding packets, we introduce a reward scheme for packet forwarding, named Protocol-Independent Fairness Algorithm (PIFA). We compare the performance of AODV and DSR with and without SLBA and PIFA. Simulation results indicate that SLBA can distribute traffic very well and improve the MANET performance. PIFA is also observed to prevent MANET partitioning and any performance degradation due to selfish nodes. 相似文献
4.
Rasmussen CD Jørgensen MB Carneiro IG Flyvholm MA Olesen K Søgaard K Holtermann A 《Ergonomics》2012,55(2):256-264
Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group. 相似文献
5.
政府角色偏离现象是构建和谐社会的政府主体障碍之一,其外在表现为:政府规模相对庞大,职权行使越位,政府诚信表现不足,行政责任意识淡化,监督主体缺位等。而探析其成因主要可以从思想观念的转变、体制法规的健全、绩效指标的选取、公务员员素质的提升四个方面入手。 相似文献
6.
7.
《Energy Policy》2014
Better methods of characterizing and addressing heterogeneity in preferences and decision making are needed to stimulate reductions in household greenhouse gas emissions. Four residential energy efficiency programs were delivered consecutively in the Region of Waterloo, Canada, between 1999 and 2011, and each offered a unique combination of information, financial reward structure, and price. A natural quasi-experimental intervention design was employed to assess differences in outcomes across these program structures. Participation at the initial (evaluation by an energy advisor) and follow-up (verification of retrofit) stages, and the material characteristics (e.g., energy performance) were measured and compared between the groups of houses included in each program at each stage. The programs appealed to people with different types of material concerns; each phase of the program was associated with houses with a different mix of material characteristics and depths of recommended and achieved changes. While a performance-based reward attracted fewer houses at each stage than a larger list-based reward, older houses with poorer energy performance were included at each stage. The findings support experimentation with program designs to target sub-populations of housing stock; future program designs should experiment more carefully and with larger performance-based rewards and test parallels with potential carbon market structures. 相似文献
8.
Luk N. Van Wassenhove Alfonso J. Pedraza Martinez 《International Transactions in Operational Research》2012,19(1-2):307-322
The demand for humanitarian aid is extraordinarily large and it is increasing. In contrast, the funding for humanitarian operations does not seem to be increasing at the same rate. Humanitarian logistics has the challenge of allocating scarce resources to complex operations in an efficient way. After acquiring sufficient contextual knowledge, academics can use operations research (OR) to adapt successful supply chain management best practices to humanitarian logistics. We present two cases of OR applications to field vehicle fleet management in humanitarian operations. Our research shows that by using OR to adapt supply chain best practices to humanitarian logistics, significant improvements can be achieved. 相似文献
9.
《Energy Policy》2015
The financial interests of U.S. utilities are poorly aligned with customer-sited solar photovoltaics (PV) under traditional regulation. Customer-sited PV, especially under a net-metering arrangement, may result in revenue erosion and lost earnings opportunities for utility shareholders as well as increases in average retail rates for utility ratepayers. Regulators are considering alternative regulatory and ratemaking approaches to mitigate these financial impacts. We performed a scoping analysis using a financial model to quantify the efficacy of mitigation approaches in reducing financial impacts of customer-sited PV on utility shareholders and ratepayers. We find that impacts can be mitigated through various incremental changes to utility regulatory and business models, though the efficacy varies considerably depending on design and particular utility circumstances. Based on this analysis, we discuss tradeoffs policymakers should consider, which ultimately might need to be resolved within broader policy contexts. 相似文献
10.
《Energy Policy》2016
This note details two comments on a recent policy proposal in Comello and Reichelstein (2014) aimed at favoring the early adoption of Carbon Capture (CC) technology in the next generation of thermal-based power plants to be installed in the United States. First, we examine the implications of a worst-case scenario in which no new CC is adopted internationally beyond what is in place in 2014. Second, we show the potential, under the original proposed subsidy, for the emergence of coordination failures capable of hampering the desired early CC deployment. We propose and evaluate modified schedules of tax-credits sufficient to overcome these concerns. These additions strengthen the argument in the original article: namely, though higher incentive levels are necessary, our findings confirm that the cost of the proposed policy is not out of reach. 相似文献