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1.
Mixed crowdsourcing is increasingly becoming the main organizational model of domestic crowdsourcing platforms. However, research on the interpretation of winning performance fails to focus on the persuasive effect of the credibility of the contractor's information source on the contractee's decision making. Based on source credibility theory (SCT), this study constructs a model of the factors influencing the contractor's bid-winning performance based on three aspects—credibility, professionalism, and attractiveness—and examines the moderating effect of positive contractor evaluations from previous tasks on the bid decision. The results reveal that integrity guarantee and contact authentication (which belong to the credibility dimension), as well as ability level and professional identity (professionalism dimension) positively affect the contractor's bid-winning performance, and that an inverted-U-shaped relationship exists between the number of services displayed by the contractors (attractiveness dimension) and bid-winning performance. 相似文献
2.
提出了一种基于信度融合和滑模控制的含分布式电源(DG)智能配电网中实现暂态电压扰动源(TVDS)容错性自动定位方法。在基于网络化电能质量监测系统平台的TVDS容错性自动定位系统框架下,对其中关键功能模块的实现原理进行详细分析,包括基于电能质量监测点优化布置的电能质量动态状态估计、扰动方向判定信度影响因素分析及信度融合、DG接入对扰动方向判定影响规律分析与归纳。然后,提出一种基于滑模控制的TVDS容错性定位算法,实现综合考虑了扰动方向融合信度、DG接入方向误判校正的TVDS容错性自动定位。最后,通过IEEE 34节点含DG配电网络算例,分析验证了所提TVDS容错性定位方法的可行性和有效性。 相似文献
3.
电力系统相继开断的分析面临着维数灾和交流潮流计算量大的瓶颈,分布因子法被广泛研究以减少其计算量。但由于分布因子法忽略了非线性因素,误差不但难以控制,并随相继开断不断积累,严重阻碍其实际应用。为了使开断潮流的计算兼具分布因子法的快速性和交流潮流法的精确性,基于摄动获取的二阶灵敏度,提出分布因子法的可信度指标,并据其判断是否需要运行一次交流潮流来消除累积误差。仿真实例表明,该指标能可靠地估计分布因子法的误差,而设计的计算框架则在保证精度的基础上,提升了计算效率。 相似文献
4.
Xuezheng Zhu Chaoshuai Han Ruiqi Liu Guohui Yan Jin Gu 《Quality and Reliability Engineering International》2021,37(4):1524-1543
For modern complex system, quality has become a serious and difficult problem that restricts the generation of combat effectiveness. Withal, based on domestic and foreign research and analysis, this paper puts forward a trade-off method for complex system reliability, maintainability, supportability, testability (RMST) design, which is suitable for product design stage. First, aiming at the uncertain problem of complex system constrained optimization, the good-point set population initialization, Deb feasibility comparison method and ε constraint method are integrated into the flower pollination algorithm, to construct the algorithm for RMST quotas design and trade-off. Second, taking the typical series-parallel repairable system as an example, one general model for complex system RMST quotas design and trade-off based on effectiveness is constructed. Finally, take an unmanned nuclear radiation detection system as a typical case, to verify its feasibility, advantages, and disadvantages. 相似文献
5.
ABSTRACTWith the rapid e-commerce growth and changes in consumers’ behaviors, many businesses are forced to adapt their business model to match their target customers’ needs. To provide consumers with more product details and increase their confidence in making online purchases, online businesses offer an online review as an alternative to physically interacting with a product. Although consumers have become familiar with the use of online product reviews, many aspects of user behavior toward the usage of online reviews are still not well understood. This study explores the factors underlying the acceptance of consumers’ online review usage when considering purchasing an item. The study results provide insight into the factors that affect customers’ use of online reviews prior to a purchase. This study furthers the body of knowledge that deals with online reviews and system usage, providing results that allow e-commerce businesses to adapt their business model to better fit consumers’ expectations. 相似文献
6.
针对时域不确定信息的融合难题,为充分体现时域信息融合的动态性特点和时间因素对融合的影响,在证据理论的基础上,提出一种考虑决策者时序偏好的时域证据融合方法。首先将决策者对时序的偏好融入时域证据融合,通过分析时域证据序列的特点,在定义时序记忆因子的基础上,对决策者的时序偏好进行度量;然后通过构建优化模型求解时序权重,再结合证据信任度的概念,对证据源进行修正;最后利用Dempster组合规则对修正后的证据进行融合。数值算例表明,与没有考虑时间因素的融合方法相比,考虑决策者时序偏好的证据融合方法可以有效处理时域信息序列中的冲突信息,得到合理的融合结果;同时,所提方法充分考虑了时域证据序列的信任度和决策者的主观偏好,可以反映决策者主观因素对时域证据融合的影响,较好地体现了时域证据融合的动态性特点。 相似文献
7.
Y. M. Zhang 《工程优选》2013,45(8):879-889
In this study, an interval credibility constrained programming (ICCP) was developed through introducing the concept of intervals into credibility constrained programming framework. Interval credibility levels can help decision makers to reflect uncertainties of preferences. By ICCP, a water resource planning model with fixed fuzzy budget was developed for supporting the planning of agriculture development and environmental protection. Surface and ground water were planned for regional irrigation in wet and normal seasons. For the interval credibility preference, best and worst cases were analysed. The tradeoff between the budget and the benefit were studied by sensitive analysis. The results showed that the current water resource budget is reasonable. 相似文献
8.
互联网上的虚假事实陈述严重影响人们有效地获取信息,如何判定事实陈述是否可信成为一个亟待解决的问题.文中提出了一种针对事实陈述的可信判定模型MFSV.该模型针对事实陈述的特点,从互联网上搜集与待判定事实陈述相关的文本信息,度量其与对应事实陈述的语义相似度;同时,该模型考虑了相关文本信息在可信度上的差别,从受欢迎程度和重要程度两个方面度量了相关文本信息来源的可信度,并获取了相关文本信息的可信度排序;根据语义相似度以及可信度排序,衡量了相关文本信息对对应事实陈述可信判定所做出的贡献,并以此为基础实现了待判定事实陈述的可信判定.一系列的实验验证了该模型的合理性及可信判定的准确性. 相似文献
9.
《Food Control》2016
Counterfeiting products and abusing labels lead to less credibility for traceability system in China recently. Authentication and supervision agencies driven by government departments play an important role for ensuring the quality safety in the case of lacking the willingness and credit of enterprises. A complete authentication and supervision flow framework was constructed based on an identification code (IdC) for authenticated origin base, which linked two actors of the agencies and the enterprises, and three subsystems of On-line Authentication Subsystem (OAS), Safety Production Management Client (SMC) and Mobile Supervision Application (MSA). IdC consisted of longitude and latitude of origin base as position code, production code and authentication type code. With a relative position partition method on 6 zones every 27° for China map and a coordination transformation algorithm, an absolute longitude and latitude value was converted into a relative position value and a zone mark value. IdC and packaging date code formed initial traceability code (TC). 8 digits packaging date code was reconstructed into 3 digits relative time value and 1 digit period mark according to a relative time period partition method with a period of 999d as time intervals and four periods form a cycle. Validation code was generated integrating the zone mark value, period mark value and authentication type code. Therefore, transformed 20 digits TC with the characters of shorter code length and stronger encryption was formed with IdC, relative time value and validation code. Three subsystems for different actors which provide the main function such as origin base registration, agency authentication, QR code generation, data uploading and product verification, were developed. The system has been used in Tianjin city from 2012. 213 enterprises were audited through OAS and used SMC. Through investigating 8 supervision agency staffs, 30 origin base owners, and 50 customers, it is shown that the positive effects are approved by most of the investigators and two negative effects for enhancing the costs and doubting the authentication reliability are laid by 17 enterprises and 12 customers. Furthermore, 4 typical cases for counterfeiting and abusing the labels were exampled and can be solved to a certain extent with the system. However, except for the technology itself, a management measures fitting the supervision flow and system need to draft in order to improve the system application well in the future. 相似文献
10.