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排序方式: 共有908条查询结果,搜索用时 36 毫秒
51.
This paper presents a novel hybrid optimization algorithm for optimizing the Distributed Generation (DG) parameters in deregulated power system which improves the stability, reduces the losses and also increases the cost of generation. This Hybrid algorithm which includes Fuzzy-Genetic Algorithm (FGA) is used to optimize the various DG parameters simultaneously. The various parameters taken into consideration are their type, location and size of the DG devices. The simulation was performed on a distribution system and modeled for steady state studies. The optimization results are compared to the solution given by another search method like Genetic Algorithm (GA) and Micro Genetic Algorithm (MGA). The results reveal the benefits of the proposed method, for solving simultaneous combinorial problems of DG devices in a power system network. 相似文献
52.
Leida Chen Anteneh Ayanso Kaveepan Lertwachara 《Journal of Computer Information Systems》2018,58(4):301-311
Prior studies suggest that the growth in online retail is attributed to the effective implementation of media-rich and interactive services and functionalities that help overcome the para-social distance between customers and online retail stores. However, few studies have offered empirical evidence that demonstrates the specific impacts these interactive services and functionalities have on the financial performance of online retailers. Using data on the operations and financial performance of the top 500 online retailers in the U.S., this study investigates the impact that website features and functionalities have on sales performance and other intermediate performance measures. Our findings suggest that website features and functionalities have a significant direct impact on sales as well as an indirect impact through intermediate performance measures. Furthermore, our model identifies the specific performance measures that each website feature targets to improve. 相似文献
53.
The development of the IEEE 802.22 standard is aimed at providing broadband access in rural areas by effectively utilizing the unused TV band, provided no harmful interference is caused to the incumbent operation. The motivation behind TV band selection is of having lower frequencies compared to other licensed bands, which, therefore, results in lower propagation path loss. Due to this quality, the spectral power density of the radio signal reduces slowly, which results in a high coverage area. Further, it has been observed that many TV channels largely remain unoccupied, as most households and businesses rely on cable and satellite TV services. This is the first international standard for a wireless regional area network (WRAN) based on cognitive radio technologies. This standard provides both PHY and MAC layer functionalities in an infrastructure based network for communication between customer premise equipments (CPEs) through a base station (BS). The Spectrum Manager is the central part of the BS, which plays a significant role in maintaining spectrum availability information, channel selection, channel management, scheduling quiet periods for spectrum sensing, accessing to the database and implementing IEEE 802.22 policies. A WRAN can particularly accommodate up to 512 CPEs in a cell. Contention may occur during initial ranging, periodic ranging, bandwidth request and urgent coexistence situation notification. The medium access control (MAC) incorporates several schemes to control contention between CPEs within a cell and overlapping cells sharing the same channel. A CPE has to make decision to resolve collisions in the upstream direction. In the case of initial ranging and periodic ranging, code division multiple access (CDMA) is employed to resolve collisions. For bandwidth and UCS notification, either a CDMA or exponential time backoff approach can be applied for collision resolution. This paper presents the analytical framework to evaluate the number of active CPEs in a cognitive radio network. It is important to note that when the arrival rate becomes equal to the service rate, the active CPEs curve attains a constant value. Further, the active CPEs length is highly dependent on service rate. The different special cases have been addressed and the effectiveness of the proposed framework has been validated through various evaluation results. 相似文献
54.
Brand pages in social media provide companies with a competitive marketing tool to create added value for their firms and customers. Past studies suggest that understanding what customers really value in brand pages is the most vital step in promoting their continued interaction, and that the relative impacts of customer values on continued interaction are contingent on individual demographic factors such as gender. However, little research has examined the relationships between customer values and their intention to engage in continued interaction, and how these relationships are moderated by gender, in the context of brand pages. This study identified eight value factors to measure customer values on brand pages, then examined their impacts on customers' continued interaction intention, and studied gender effects on the latter relationship. Our proposed hypotheses are mostly supported by data collected from users of Sina Microblog brand pages and analyzed by partial least squares. 相似文献
55.
The present study applies a business model framework to a water utility using a case study. A survey was developed and conducted with residential water customers in the City of Guelph, ON, Canada, with the objective of assessing their expectations in order to improve the business. Preferences differed by user type, underlining the benefit of distinguishing between customer segments (or user types) and customizing messaging. Users were not aware of all services covered by their water bill, and although expecting high quality services they did not support rate increases. Stakeholder collaborations could be used to improve awareness, offer decentralized solutions, and resolve issues collectively. 相似文献
56.
The Customer Forum was set up in 2011 to carry out customer research, represent the interests of customers to Scottish Water and the economic regulator WICS, and to seek to agree a business plan with the company. It was set up with the agreement of all parties. The aims were to improve on previous price control approach, to find a new way of challenging the company and to bring greater customer input to bear. The constitution, expectations and timetable of the Forum were specified in some detail. WICS also provided many Guidance Notes about its own expectations. Financial tramlines were established to monitor performance during the forthcoming price control period. The process worked well, all parties worked constructively and agreement was reached on a business plan upon which the regulator subsequently proposed a price control. There is scope to apply the process in future and in other sectors. 相似文献
57.
In this article we compare and contrast elements of social capital across different housing tenures in an Adelaide neighbourhood. Using the results of 530 self-completion questionnaires and in-depth qualitative interviews with 16 people we assess perceptions of conflict across housing tenures and between socio-economic groups, feelings of acceptance and belonging in the local neighbourhood, and levels of involvement in local formal and informal networks. While only a small number of questionnaire respondents reported negative views of socio-economic diversity in the area a theme emerging in the qualitative data indicated that housing tenure was relevant to some of these negative perceptions. Respondents from across different tenure types also reported differences in feelings of acceptance in the neighbourhood, and involvement in formal and informal networks. The study findings suggest that housing tenure is relevant to the development of neighbourhood-based social capital, and that this factor needs to be considered by social planners, housing policy makers and others involved in implementing social mix policies. In addition, the findings indicate the need to consider the community housing and public housing tenures in their own right, given the different models of housing provision, rather than collectively under the common banner of social housing as most research studies do. It is recommended that the full diversity of housing tenure is considered in any future analysis. 相似文献
58.
在分析了目前传统查书方式的缺点和短信查询优势的基础上提出了利用短信实现客户服务的系统模型,详细分析其实现方案.并讨论了关键技术和解决方法.该系统现已投入使用,具有接入简单,处理迅速,可扩展性好等特点. 相似文献
59.
本文针对ISO/TS16949中关于"增强顾客满意"和"顾客满意"的两个不同层次的管理,进行了探讨. 相似文献
60.