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91.
对于分布式的认知无线网络,由于不存在融合中心节点,次级用户节点之间的合作感知往往
采用信息交互的渠道进行,其中一种基于共识合作的感知机制受到广泛的研究,但这种机制
在鲁棒性方面存在一定的缺陷,当恶意节点存在时,其错误信息将影响局部的感知判决结果
,为此,提出一种基于感知节点可信度的共识合作感知机制。在该机制中,各节点对邻居节
点的可信度进行计算,并把计算出的可信度值发送给其他节点,通过对各节点可信度的累加
计算,最终计算出各节点的可信度,各节点以此决定是否与其邻居节点合作以及如何合作。
仿真结果证明,在恶意节点存在的情况下,该算法在感知性能和收敛速度上都较未改进算法
有不同程度的提升,减轻了不可靠节点对合作感知结果的影响。 相似文献
92.
93.
本文对汉语方位词"里"(中、内)和"外"在汉语中的不对称分布状况进行了调查归类,并对其产生的原因从认知学角度进行了分析和探索。 相似文献
94.
Hameedah Sayani Muneeza Shoaib Neelofer Mashood 《Journal of Education for Business》2019,94(2):101-112
Higher education institutions are increasingly employing competitive formats such as case study competitions in business education to enhance students’ learning experience. The authors explore students’ perceptions and experiences regarding affective, cognitive, and skills development factors and whether these perceptions and experiences determine students’ participation in case study competitions in the United Arab Emirates. The authors attempt to contribute to the rather nascent body of literature on case study competitions. The results highlight statistically significant differences between perceived and actual learning with respect to cognitive and affective benefits. Furthermore, a significant positive association is found between participation in case study competitions and respondents’ perceptions and real experiences about various aspects of learning. 相似文献
95.
Stephen Wilkins Muhammad Mohsin Butt Farshid Shams Andrea Pérez 《Journal of Strategic Marketing》2019,27(3):210-226
In order to satisfy the Muslim market segment, many restaurant and fast food companies in Western countries have standardised their products by switching to halal. The purpose of this research is to discover the extent to which non-Muslim consumers in non-Muslim countries experience cognitive dissonance when they think about restaurants and fast food outlets having likely served them halal-produced food, and the extent to which these consumers intend to repurchase halal food. Data came from a total sample of 1097 non-Muslim consumers in Canada, Spain and the United Kingdom. The full model, with religious identity, ethnic identification and interest in animal welfare as antecedents of cognitive dissonance, explained 35% of the variance in consumers’ repurchase intentions. Our findings suggest that many non-Muslims do not have a particular issue with consuming halal food, but they may react negatively if they unintentionally consume halal food and perceive that they have been deprived of information, or worse still, deliberately deceived. The research makes a number of contributions to marketing knowledge with regard to the negative spillover effects that can result from faith-based product standardisation, and the influences of consumer interest in animal welfare and deprivation of product information on consumer behaviour. 相似文献
96.
传统认知无线网络功率分配时,一般假定主用户(Primary User,PU)状态在一帧内不发生变化,并且未考虑传输时延的问题。在下一代移动网络中,由于主用户活跃程度的提高以及严格的时延要求,上述问题是功率资源分配时亟需考虑的重要方面。针对这种问题,以最大化认知用户可获得的有效容量为目标,采用基于感知/传输帧结构的四状态三功率传输策略,从而满足时延约束要求,且考虑了主用户的活跃程度。建立了系统以及状态转移模型,设计了使用服务质量(Quality of Service,QoS)约束的平均信道有效容量优化函数,采用Lagrangian方法详细分析推导了最佳有效容量的理论近似值,并对影响有效容量的不同因素进行了仿真分析。与传统的传输策略相比,在保证主用户正常通信的前提下,采用所提算法,认知用户的有效容量得到了显著提高。 相似文献
97.
Although flexibility has been considered critical in responding to uncertainty in a business environment, few studies have explored firms' flexibility in sustainable development. To understand the nature of firms that can respond better to uncertainty in their sustainable development practices, this study defines sustainable development flexibility and investigates the mechanism underlying its formation. The study proposes a conceptual framework on the interactions of managers' environmental attitude and cognitive style, as well as firms' information integration on sustainable development flexibility. A questionnaire survey was developed to test the corresponding hypotheses, and 241 valid responses were received from middle- and top-level managers in Chinese firms. The results show that (a) the higher the manager's environmental attitude, the higher the firm's information integration and greater sustainable supply chain flexibility, and (b) the more intuitive the manager's cognitive style, the greater the impact of environmental attitude on sustainable development flexibility. 相似文献
98.
People must often wait for days or weeks to receive test results, price quotes, products, etc. Service providers may manage user experience during such in-process waits using notification systems that inform users when a response is available or inquiry systems that require users to inquire about response availability, thereby imposing prospective memory requirements on users. Based on the prospective memory and wait time literature, we make predictions regarding how response system (notification vs. inquiry) moderates the effects of waits that are shorter or longer than the provider promised on user evaluation of the wait. We find that users of a notification system evaluate a wait more positively and are less sensitive to deviations of actual from promised wait time than are users of an inquiry system. This advantage was more pronounced for a wait that was longer (vs. shorter) than promised. These effects of system and expectation on evaluation were fully mediated by their impact on the cognitive and physical effort of navigating the system. Finally, a week after having experienced a wait, users of an inquiry system who had waited longer (vs. shorter) than promised cooperated less on a follow-up task, highlighting another downside of using an inquiry system. 相似文献
99.
This study was designed to identify the attributes of a halal-friendly hotel and evaluate the role of these attributes in motivating the behavioral intentions of Muslim customers. Qualitative and quantitative approaches identified 30 validation and reliability items involving five distinctive dimensions, which included halal-friendly service, facilities, foods and beverages, privacy, and customer-service equality. The findings from the structural model indicate that the proposed model sufficiently explains the variance in intentions; three attributes were positively related to cognitive evaluation, and four attributes had significant influence on affective evaluation. In addition, the results indicated that cognitive and affective evaluation worked as mediators. 相似文献
100.
在认知无线电网络中,图论与量子遗传算法相结合的频谱分配策略能够提高频谱利用率,但存在早熟和收敛精度不够等缺点。为了解决该问题而实现算法的优化,对图着色理论的频谱分配模型进行数学建模,并针对该模型提出了改进的量子遗传算法。首先,通过使用小生境技术初始化种群,使种群分布更加广泛、算法的收敛度更高;其次,根据进化代数对量子旋转角进行实时动态调整,对染色体进行阈值变异,防止个体陷入早熟,跳出局部解;然后,对干扰约束条件进行重新设计,有效地避免盲目性,提高了网络的公平性和网络效益。仿真结果表明,所提算法有效地提高了频谱利用率,极大地增强了网络系统的性能。 相似文献