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991.
Jin'ao Yu Xiaogang Tang Shibing Zhu Haopeng Sun Lunxin Zhong Guangyu Yang 《北京理工大学学报(英文版)》2021,30(1):82-90
This paper investigated a QoS-aware power allocation for relay satellite networks. For the given QoS requirements, we analyzed the signal model of relay transmission and formulated the power minimization problem which is non-convex and difficult to solve. To find the optimal solution to the considered problem, we first analyzed the optimization problem and equivalently turn it into a convex optimization problem. Then, we provided a Lagrangian dual-based method to obtain the closed-form of the power allocation and provided an iterative algorithm to the optimal solution.Moreover, we also extended the results to the cooperative transmission mode. Finally, simulation results were provided to verify the superiority of the proposed algorithm. 相似文献
992.
Shailendra Singh Bisht 《Behaviour & Information Technology》2016,35(10):817-832
A key agenda of policy-makers in both the developing and the developed worlds is to have an inclusive growth. Financial services have been recognised as one of the fundamental services that have the potential to achieve this objective and help move towards a more just and equitable society. This paper attempts to assess the impact of three information and communication technology-driven initiatives in the field of financial services by differentiating them on the basis of service design. This study goes beyond the stated objective of these services and uses Sen’s capability perspective to study their impact across three non-economic outcome variables viz. literacy, service-specific well-being and empowerment. The data for the study are collected from the urban poor across different locations in a large metropolitan city in South India where the three different services are being offered. The study follows a quasi-experimental design (field study) and ensures matching of the treatment and control groups through propensity score matching. The matched data are analysed using an independent sample t-test. The result of the analysis shows that service design plays a key role in increasing service literacy, improving service-specific well-being and empowering end users. The study suggests that the true challenge for providers (government and partner agencies) of these services is in designing a service that ensures a balance of structure and flexibility without constraining the choice of end users through innovative service blueprints. 相似文献
993.
Mobile crowd sensing (MCS) is a novel class of mobile Internet of Things (IoT) applications for community sensing where sensors and mobile devices jointly collect and share data of interest to observe phenomena over a large geographic area. The inherent device mobility and high sensing frequency has the capacity to produce dense and rich spatiotemporal information about our environment, but also creates new challenges due to device dynamicity and energy constraints, as well as large volumes of generated raw sensor data which need to be processed and analyzed to extract useful information for end users. The paper presents an ecosystem for mobile crowd sensing which relies on the CloUd-based PUblish/Subscribe middleware (CUPUS) to acquire sensor data from mobile devices in a flexible and energy-efficient manner and to perform near real-time processing of Big Data streams. CUPUS has unique features compared to other MCS platforms: It enables management of mobile sensor resources within the cloud, supports filtering and aggregation of sensor data on mobile devices prior to its transmission into the cloud based on global data requirements, and can push information of interest from the cloud to user devices in near real-time. We present our experience with implementation and deployment of an MCS application for air quality monitoring built on top of the CUPUS middleware. Our experimental evaluation shows that CUPUS offers scalable processing performance, both on mobile devices and within the cloud, while its data propagation delay is mainly affected by transmission delay on wireless links. 相似文献
994.
995.
内部营销把员工看作是企业最初的内部市场,在把服务通过营销活动推向外部市场之前,先对内部员工进行营销。内部营销是企业提高服务质量的前提。为了有效开展内部营销,服务企业应进行内部市场调研,细分企业内部员工市场;加强培训,使员工树立顾客导向的服务观念;针对员工的需求,切实激励与认同;尊重员工,赋予员工适当的权利;加强信息交流与沟通,统一思想和行动。 相似文献
996.
随着工业互联网、车联网、元宇宙等新型互联网应用的兴起,网络的低时延、可靠性、安全性、确定性等方面的需求正面临严峻挑战。采用网络功能虚拟化技术在虚拟网络部署过程中,存在服务功能链映射效率低与部署资源开销大等问题,联合考虑节点激活成本、实例化开销,以最小化平均部署网络成本为优化目标建立了整数线性规划模型,提出基于改进灰狼优化算法的服务功能链映射(improved grey wolf optimization based service function chain mapping,IMGWO-SFCM)算法。该算法在标准灰狼优化算法基础上添加了基于无环K最短路径(K shortest path,KSP)问题算法的映射方案搜索、映射方案编码以及基于反向学习与非线性收敛改进三大策略,较好地平衡了其全局搜索及局部搜索能力,实现服务功能链映射方案的快速确定。仿真结果显示,该算法在保证更高的服务功能链请求接受率下,相较于对比算法降低了11.86%的平均部署网络成本。 相似文献
997.
Economic Evaluation of Power System Flexibility by Commercial Air Conditioner Control with Large Penetration of Photovoltaic Generation 下载免费PDF全文
High penetration of intermittent renewable energy such as photovoltaic (PV) and wind power could cause shortage of power system flexibility. Demand response is expected to help supply ancillary service instead of the conventional power plant. Commercial air conditioners are a promising responsive load for demand response because they account for a large proportion of power consumption in the power system. We calculate a system operation cost and hourly operation pattern of each power plant by using the optimal power generation model considering flexibility supply from controlling commercial air conditioner. We obtained the following results as an effect of commercial air conditioner control. (1) The power generation of oil fired power plants decreases at peak time and annual fuel cost of oil fired plant is reduced by approximately 30% at most in Kanto area. (2) The percentage of rated operation mode of LNG combined cycle plants increases. (3) Curtailed energy rate of PV decreases because a power storage amount by pumped hydropower generation increases. (4) Required battery capacity to reduce PV curtailed amount decreased by combining battery energy storage system in case of high penetration of PV. 相似文献
998.
社区和居家养老是我国当前和未来的主要养老模式,然而,与机构养老设施相比较而言,我国社区居家养老服务设施的发展明显滞后,具体表现为设施的建成基础薄弱、空间资源的配置要素模糊、规范和管控手段缺位等。在概述现状与问题的基础上,系统地探讨了我国社区层面养老服务资源的配置主体、配置对象和配置思路。针对养老服务需求和供给主体日益多元化的挑战,提出结合社区实际情况灵活配置服务模块的建议,采用总量控制和复合设置的规划手段落实配建,从而实现服务设施综合效益最大化的建设目标。 相似文献
999.
1000.
杨帆 《吉林化工学院学报》2020,37(10):79-82
近年来,以推进基本公共服务均等化为依托而促进养老等社会服务的发展已成为各省市的重点工作之一,立足于吉林市市情,通过调查研究、定量分析等方式探索本地社区养老存在的问题以及对策。 相似文献