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1.
为了提高双离合变速器在车辆上的换挡品质,提升电气化换挡执行机构的工作效率,给出执行机构性能与换挡品质评价准则;通过两种不同双离合变速器电控电动执行机构的工作原理与性能分析,基于MATLAB数值仿真方法优化出最高效率进行试验.基于车辆6个维度的换挡工况对二者所搭载的变速器分别进行试验与CAN线数据采集,对比研究两种机构优缺点,通过雷达图的方式进行优劣说明.结果表明,两种执行机构传动效率可达70%且换挡品质相当.可见Tip in tip out工况对二者要求最为严格.  相似文献   
2.
林福兆 《价值工程》2021,40(7):63-64
积极思考工程施工质量改善创新方法,有助于机电工程建设水平的优化发展.基于此,本文从创新机电工程施工质量提高方法的重要性展开论述,详细阐述了对树立精益化施工质量改善理念、做好施工质量提升方法创新资料的管理、构建良好的创新意识形态氛围、夯实创新的人力资源基础这几项提高机电工程施工质量方法的创新思考,希望能够助力机电领域的发展.  相似文献   
3.
增加选择数量是否会提高满意度是经济学、心理学和营销学的热点问题。当消费者对某一刺激目标同时存在积极和消极的评价时,即矛盾态度怎样影响选择数量和满意度的关系?2个实验结果表明,选择数量对满意度的影响是通过决策困难水平实现的,当选择数量影响决策困难水平时,会产生选择超载。矛盾态度对决策困难水平与满意度的关系有调节作用,对矛盾态度较高者,选择“多多益善”,选择数量增加使消费者满意度提高;相反,对矛盾态度较低者,选择“适可而止”,选择数量增加使消费者满意度降低。  相似文献   
4.
近年来在大学生素质教育的过程中,单一的课堂教育已经无法满足学生需求。第二课堂作为第一课堂的拓展性载体,能够通过对第一课堂的拓展为大学生营造良好的学习环境与身心健康成长的氛围,有助于素质教育工作的开展。高校应重视第二课堂的设计,在第二课堂的支持下全面开展素质教育工作,通过多种措施培养学生的专业素质和综合素养,为大学生的后续发展夯实基础。  相似文献   
5.
林建锋 《价值工程》2021,40(16):133-134
随着我国数据中心制冷设备制造技术不断发展,对设备结构的设计质量及可靠性要求越来越高.为改善某项目电加热支架结构运输后的断裂问题,利用ANSYS有限元分析方法对加热器支架运输断裂问题进行静力学、随机振动分析,确认电加热支架结构应力分布、安全系数薄弱位置,并通过对电加热支架结构"几型"的设计优化,在多个项目中应用且运输到西北地区后观察均未出现振动断裂现象,取得良好的改善效果.  相似文献   
6.
We examine factors affecting the adoption of improved cassava varieties of 217 households in the Cauca Department in southwest Colombia. Using DNA fingerprinting through Single Nucleotide Polymorphisms (SNPs), we identified different cultivars in farmers fields. We also used this information to remove possible bias in the adoption model that could have resulted from a misclassification of improved varieties (IVs). As a result, we found that farmers substantially overestimate their use of IVs and there are important differences in the determinants of adoption between farmer self‐identification and DNA fingerprinting. This finding implies that the incorporation of DNA fingerprinting in IV adoption studies is important to ensure the accuracy of future agricultural economic research and the relevance of subsequent policy recommendations.  相似文献   
7.
This study examines how relationship innovation can be developed in global collaborative partnerships (alliances, joint ventures, mergers, and acquisitions). The recently emerging theory of big data analytics linked with traditional organizational powers has attracted a growing interest, but surprisingly little research has been devoted to this important and complex topic. Therefore, after developing the theoretical foundations, our study empirically quantifies the links between the theoretical constructs based on the data collected from chief executive officers, managing directors, and heads of departments who work in contemporary global data‐and‐information driven collaborative partnerships. The results from structural equation modeling indicate that the relationship innovation depends on the power of big data analytics and non‐mediated powers (NMP, expert and referent). The power of big data analytics also mediates the correlation between NMP and relationship innovation. However, mediated powers (coercive and manipulative) negatively affect the power of big data analytics and relationship innovation. The interaction effects further depict that analytically powered partnerships have better relationship innovation compared with those which focus less on the analytical power. Consequently, the contributions of this study provide a deeper understanding of mechanisms of how modern collaborative partnerships can use big data analytics and traditional organizational powers to co‐create relationship innovation.  相似文献   
8.
This study examines whether difficult targets and quality indicators in executives' pay‐for‐performance (P4P) plans affect performance. The impact of target‐setting and P4P plans on quality improvement in the public sector is unclear. The Ontario government initiated the Quality Improvement Plan (QIP), which requires hospitals to set targets for quality indicators annually and link executive pay to target achievement since 2011. Analyzing Health Quality Ontario's database and hospitals' 2012–2013 QIPs, this study shows greater quality improvement in hospitals with difficult targets than hospitals with easy targets or without assigned targets; however, the positive impact disappears for high‐performance hospitals relative to their peers. We find no significant effect of the use of quality indicators in executives' P4P plans on quality improvement. Copyright © 2018 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
9.
We propose parametric copulas that capture serial dependence in stationary heteroskedastic time series. We suggest copulas for first‐order Markov series, and then extend them to higher orders and multivariate series. We derive the copula of a volatility proxy, based on which we propose new measures of volatility dependence, including co‐movement and spillover in multivariate series. In general, these depend upon the marginal distributions of the series. Using exchange rate returns, we show that the resulting copula models can capture their marginal distributions more accurately than univariate and multivariate generalized autoregressive conditional heteroskedasticity models, and produce more accurate value‐at‐risk forecasts.  相似文献   
10.
This paper considers a duopoly market with horizontally differentiated system goods to examine system owners' behaviors under supporting software delegation, in which owners of system firms use varieties of supporting software, coupled with profit, to evaluate their managers' performance. Supporting software delegation seems to induce managers to act more aggressively in price competition than sales delegation does; however, we prove that if two systems are compatible and the varieties of supporting software are determined by hardware owners' overall expenditure amount on software, then supporting software delegation is equivalent to sales delegation. Owners of system firms induce their managers to act less aggressively in hardware price competition by offering contracts with a negative weight on varieties of supporting software under supporting software delegation. We find that stronger network externalities do not reverse system owners' contracting behaviors under supporting software delegation. Finally, it is worth mentioning that hardware technologies are static in this paper. In other words, dynamic changes such as hardware evolution are not considered in our analysis.  相似文献   
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