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51.
Electric vehicles (EV) use an eco-friendly technology that limits the greenhouse gas emissions of the transport sector, but the limited battery capacity and the density of the battery are the major barriers to the widespread adoption of EV. To mitigate this, a good method seems to be the innovative wireless charging technology called ‘On-Line EV (OLEV)’, which is a contactless electric power transfer technology. This EV technology has the potential to charge the vehicle’s battery dynamically while the vehicle is in motion. This system helps to reduce not only the size of the battery but also its cost, and it also contributes to extending the driving range before the EV has to stop. The high cost of this technology requires an optimal location of the infrastructure along the route. For this reason, the objective of this paper is to study the problem of the location of the wireless charging infrastructure in a transport network composed of multiple routes between the origin and the destination. To find a strategic solution to this problem, we first and foremost propose a nonlinear integer programming solution to reach a compromise between the cost of the battery, which is related to its capacity, and the cost of installing the power transmitters, while maintaining the quality of the vehicle’s routing. Second, we adapt the multi-objective particle swarm optimization (MPSO) approach to our problem, as the particles were robust in solving nonlinear optimization problems. Since we have a multi-objective problem with two binary variables, we combine the binary and discrete versions of the particle swarm optimization approach with the multi-objective one. The port of Le Havre is presented as a case study to illustrate the proposed methodology. The results are analyzed and discussed in order to point out the efficiency of our resolution method.  相似文献   
52.
针对突发信号解调中多普勒频偏大的问题,提出了一种改进的连续相位移频键控信号(CPFSK)频率估计方法。首先接收信号平方运算使信号的调制指数加倍,再通过一次离散傅里叶变换(DFT),用搜索信号平方谱谱峰的方法实现突发信号频率估计。仿真实验表明,在低信噪比条件下,该算法的频率估计精度比经典的相位差频率估计算法提高了20%;该算法与广泛用于高动态突发信号的频率插值估计算法相比,同道干扰信道下信干比改善可达4 dB,DFT长度缩短约1/3。  相似文献   
53.
Influencers are ordinary individuals who have amassed large followings by demonstrating expertise in various niches on social media sites. We aim to propose (1) the visual presentation of an Influencer's extroversion as an antecedent to source credibility and purchase intentions and (2) personality matching in terms of extroversion between an Influencer and their audience as a moderator of such relationships. We chose the source credibility model and the similarity-attraction model as our theoretical frameworks. In our controlled online experiment (n = 165), the profile of a brand ambassador of a fashion brand was curated to create two levels of extroversion (i.e. low vs. high extroversion). Participants' self-reported extroversion levels were counterbalanced in these two conditions to create a personality match with the Influencer, entitled “extroversion congruence.” Our results suggest that the visual presentation of an Influencer's extroversion increases the perceived credibility of the Influencer and subsequent purchase intentions. Additionally, our findings show that these relationships were asymmetrically moderated by extroversion congruence: the positive effects of extroversion increase in the case of high extroversion among both the Influencer and their audience but decrease in the case of low extroversion.  相似文献   
54.
55.
面对日趋复杂的外部环境,组织变革成为企业获得竞争力的重要方式。员工参与是组织变革成败的关键,充足的组织变革信息有利于员工积极投入变革。本文以社会信息加工理论为基础,对来自被兼并企业的36个工作团队185名员工进行研究,探索多渠道变革信息传递对员工的影响机制。基于多层次线性模型的数据分析结果表明:(1)变革情境下,组织正式渠道进行信息沟通和变革氛围包含的非正式信息,均能正向促进员工变革绩效;(2)员工所持有的积极变革期望,在多渠道信息传递和变革绩效间起到中介作用;(3)变革氛围跨层调节变革信息沟通对员工积极变革期望的正向作用,相比于低变革氛围情景,具有高变革氛围的团队,通过变革信息沟通更能显著提升员工对变革的积极期望。研究结论对企业变革实践中信息传递和沟通工作具有现实指导意义。  相似文献   
56.
王玉雅  韩守杰 《价值工程》2014,(11):274-275
总结比赛经验,充实教学内容,深化教学改革,使培养出的学生成为企业的首选。对于高职院校人才培养,要求工程造价专业的学生通过学习,具备建筑预算行业人才要求,成为造价师的储备人才。  相似文献   
57.
Abstract

This paper critically reviews 19 studies published between 1972 and 2012 that investigated the written and/or oral communication skills of practicing accountants. The core aim of the review was to identify skills considered important and highlight gaps regarding what is known about existing and desired communication skills in the accounting profession. Key findings include that most studies did not detail the basis used to select the skills examined, used very broad skill-set categories and/or did not sufficiently incorporate information already established in the literature. Differing views on the importance of communication skills were found between educators and accountants. Knowledge gaps identified relate to the communication skills considered most important at varying career stages and different career paths, the specific types of oral and written communication skills needed and the role and importance of oral versus written and informal versus formal communication skills. A fundamental concern is that much of the existing communication skills research is crucially out of date. Of the 19 studies reviewed, only three have been published in the past decade. This suggests that further research is needed in the area.  相似文献   
58.
刘丹丹  樊镓豪 《价值工程》2015,34(16):62-65
在国家大力推进产业结构调整、信息化的压力下,物联网技术和O2O商业模式作为信息时代的新型生产力,在国内的普及率并不高。本文运用案例分析的方法通过研究大学生创业项目引入O2O商业模式的概念,并与物联网技术有机结合,把握两者之间优势互补的关系,提出两者创新应用,同时从商业模式构成要素的角度对该模式进行系统、深入分析,为中国现代农业信息化建设和结构调整提供了新思路。  相似文献   
59.
江涌 《价值工程》2015,(3):270-271
随着指挥信息系统在全军的广泛运用,指挥方式由传统的"树状"改变为"网状"、"扁平状"。然而现通信部队在开展指挥信息系统训练、应用上还存在一定的短板,在提高整个部队的指挥能力上无法提供高效支持,文章对通信部队的指挥信息系统在实际运用上进行了初步分析,并指出了目前存在的不足,对如何提高通信部队利用指挥信息系统提高整体作战能力提出了对策和建议,对提高指挥信息系统在实际中的应用具有积极意义。  相似文献   
60.
针对复杂电磁环境下卫星移动通信系统可靠通信需求,利用频谱地图多维数据呈现优势,提出了基于多维频谱地图的干扰规避方法。通过建立卫星移动通信系统波束、时隙、子频带、干扰强度等多维信息关联的频谱地图,利用数据挖掘方法对频谱可用情况进行预测,基于预测结果及用户QoS(Quality of Service)需求生成干扰规避策略,通过星地联合频谱资源调配实现系统干扰规避。该方法为卫星移动通信系统干扰规避提供了一种全新的思路,可提升卫星移动通信系统干扰防护能力。  相似文献   
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