To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated ...To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated QoS-aware job dispatching policy is proposed, which correlates priorities of incoming jobs used for job selecting at the local scheduler of the grid node with the job dispatching policies at the global scheduler for computational grids. The stochastic high-level Petri net (SHLPN) model of a two-level hierarchy computational grid architecture is presented, and a model refinement is made to reduce the complexity of the model solution. A performance analysis technique based on the SHLPN is proposed to investigate the QoS-aware job scheduling policy. Numerical results show that the QoS-aware job dispatching policy outperforms the QoS-unaware job dispatching policy in balancing the high-priority jobs, and thus enables priority-based QoS.展开更多
A heuristic theoretical optimal routing algorithm (TORA) is presented to achieve the data-gathering structure of location-aided quality of service (QoS) in wireless sensor networks (WSNs). The construction of TO...A heuristic theoretical optimal routing algorithm (TORA) is presented to achieve the data-gathering structure of location-aided quality of service (QoS) in wireless sensor networks (WSNs). The construction of TORA is based on a kind of swarm intelligence (SI) mechanism, i. e. , ant colony optimization. Firstly, the ener- gy-efficient weight is designed based on flow distribution to divide WSNs into different functional regions, so the routing selection can self-adapt asymmetric power configurations with lower latency. Then, the designs of the novel heuristic factor and the pheromone updating rule can endow ant-like agents with the ability of detecting the local networks energy status and approaching the theoretical optimal tree, thus improving the adaptability and en- ergy-efficiency in route building. Simulation results show that compared with some classic routing algorithms, TORA can further minimize the total communication energy cost and enhance the QoS performance with low-de- lay effect under the data-gathering condition.展开更多
This paper investigates on the base stations(BSs) sleeping control and energy saving in wireless network. The objective is to find the sleeping control and energy saving configuration between total power consumption a...This paper investigates on the base stations(BSs) sleeping control and energy saving in wireless network. The objective is to find the sleeping control and energy saving configuration between total power consumption and average video's quality. On the Software Defined Network(SDN) access network architecture, a type of sleeping control and active BSs' optimal transmitting time strategy is considered, the BS sleeps when there is no active users, and wakes up after a period of vacation time. In this paper, we study the active users grouping strategy, In order to spare more BSs into sleeping mode. Then this paper proposes an active BS transmitting time optimal strategy according to the users' Qo S. In the proposed strategy, the active BSs' transmitting time is minimized in order to save energy. This paper employs the mixed integer-programming model to present this optimization problem. Then we utilized a novel algorithm to save the energy in access networks and also meet the Qo S requirements. Both the analytical and simulation results show that the algorithm can effectively save energy in the access network BSs.展开更多
Based on the cross-layer design, the power-optimization problem of Macro-Femto Heterogeneous Networks (HetNets) has been formulated. The constraints of power and re-source block allocation in the physical layer, del...Based on the cross-layer design, the power-optimization problem of Macro-Femto Heterogeneous Networks (HetNets) has been formulated. The constraints of power and re-source block allocation in the physical layer, delay and target data rate in the medium ac-cess control layer, urgent queue length in the network layer, and packet error rate in the transport layer, have been considered. The original problem is non-deterministic polyno-mial time hard, which cannot be solved practi-cally. After the restrictions of upper layers are translated into constraints with physical layer parameters, and the integer restrictions are relaxed, the original problem can be decom- posed into convex optimization subproblems. The optimal solutions of resource block allo-cation and power allocation can be obtained by using the Lagrangian optimization. Simula-tion results show that the proposed scheme is better than both the round robin algorithm and the max-rain one in terms of energy efficiency, throughput and service fairness. The round robin algorithm and the max-min one only focus on the user fairness rather than quality of service fairness. Compared to the round robin scheme (the max-min one), the proposed scheme improves the energy efficiency 58.85% (62.41%), the throughput 19.09% (25.25%), the service fairness 57.69% (35.48%).展开更多
The power of employees is usually under estimated by managers in an organization. In order to achieve effectively the organizational objectives and compete externally, leaders must appreciate the importance of the e...The power of employees is usually under estimated by managers in an organization. In order to achieve effectively the organizational objectives and compete externally, leaders must appreciate the importance of the employees and help them to do right things to the organization. The process to develop powerful employees, enhance a learning culture and recognize the achievements is the important element to employee satisfaction. The winner of the 21st century is the one who can understand and apply the strategy of people.展开更多
[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [...[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [Method] The val- ues of ecosystem function was estimated by market value method, opportunity cost approach, replacement cost method, shadow engineering approach, travel cost method, hedonic pricing method and contingent value method. [Result] With wetland ecosystem service function value totals 4.968 billion yuan, the value of eco-environ- ment regulation and maintenance was the highest, followed by the value of cultural and social function. The value of material production was the least. The values of sub-functions can be concluded by comparison of service function va}ue and pro- portions, as follows: flood mitigation 〉water purification 〉water conservation 〉 tourism&leisure〉material production〉scientific research and education〉water supply〉 biodiversity maintenance〉regulation on atmosphere constituents. [Conclusion] The re- search performed quantitative evaluations on ecosystem service function values of wetlands in Chao Lake and is of significance for specific development and protec- tion of local wetlands.展开更多
Cognitive radio sensor network is applied to facilitate network monitoring and management, and achieves high spectrum efficiencies in smart grid. However, the conventional traffic scheduling mechanisms are hard to pro...Cognitive radio sensor network is applied to facilitate network monitoring and management, and achieves high spectrum efficiencies in smart grid. However, the conventional traffic scheduling mechanisms are hard to provide guaranteed quality of service for the secondary users. It is because that they ignore the influence of diverse transition requirements in heterogeneous traffi c. Therefore, a novel Qo S-aware packet scheduling mechanism is proposed to improve transmission quality for secondary users. In this mechanism, a Qo S-based prioritization model is established to address data classification firstly. And then, channel quality and the effect of channel switch are integrated into priority-based packet scheduling mechanism. At last, the simulation is implemented with MATLAB and OPNET. The results show that the proposed scheduling mechanism improves the transmission quality of high-priority secondary users and increase the whole system utilization by 10%.展开更多
This paper resumes a research project developed in the concession area of AES Eletropaulo, the largest electrical energy distribution company in Brazil. First, the global standards of information exchange within power...This paper resumes a research project developed in the concession area of AES Eletropaulo, the largest electrical energy distribution company in Brazil. First, the global standards of information exchange within power transmission and distribution area were evaluated, allowing the definition of state of the art on the theme, followed by determining its applications considering technologies already applied by the company. The specifications needed for the generation of a data integration model are adapted to radial overhead network at company concession area. The project developed an intermediary connectivity layer, based on the CIM (common information model), which enables corporative systems to communicate in a standard way, through the use of integrating technologies. It, therefore, enabled modeling all main subjects of an electrical network in an open, extensible and non-proprietary way, in a model that contains classes and attributes of such subjects, as well as their relationships. Calculation and planning products adopted by the company were integrated to the technological layer implemented.展开更多
Advanced Metering Infrastructure (AMI) enables smart grids to involve power consumers in the business process of power generation transmission, distribution and consumption. However, the participant of consumers cha...Advanced Metering Infrastructure (AMI) enables smart grids to involve power consumers in the business process of power generation transmission, distribution and consumption. However, the participant of consumers challenges the current power systems with system integration and cooperation and security issues. In this paper, the authors introduce a service-oriented approach to AMI aiming at solving the intercommunication problem and meanwhile providing a trust and secure environment for smart grids. In this approach heterogeneous systems expose services to the network. System integration and cooperation are done through service composition. A generic service interfacing method is designed to develop standardized services for heterogeneous power systems. Moreover, role-based access control mechanism is used to guarantee the secure access to smart grids. With the seamless communication between consumers and power systems and among power systems themselves, this service-oriented AMI can associate consumers with actual system workload and furthermore support the intelligent running of power systems.展开更多
Standard e-government information system(SEIS) including mobile-government applications are playing more and more important roles in the establishing of national e-government framework. It can be beneficial not only f...Standard e-government information system(SEIS) including mobile-government applications are playing more and more important roles in the establishing of national e-government framework. It can be beneficial not only for avoiding redundant e-government IS development but also for improving collaboration among government agencies. Two research questions were explored: what are the factors influencing the performance of SEIS? Will mandatory SEIS create a better performance than non-mandatory SEIS? Specifically, the use of five categories of IS aspects--information system quality, online service quality, offline service quality, diffusion modes and standard network size—is proposed to understand the performance of SEIS through applying both survey study and simulation study. The results show that information system quality and online service quality of SEIS have strong effects on users' expectation and users' satisfaction, which thereafter promotes the performance of SEIS. Government agencies' offline service quality shows a significant effect on users' satisfaction while not on users' expectation. Furthermore, the diffusion speed of SEIS in non-mandatory and mandatory modes and the standard network size also have great influence on the utility of SEIS.展开更多
The energy efficiency(EE) of distributed antenna system with quality of service(Qo S) requirement is investigated over composite Rayleigh fading channel,where the shadow fading,path loss and Rayleigh fading are all co...The energy efficiency(EE) of distributed antenna system with quality of service(Qo S) requirement is investigated over composite Rayleigh fading channel,where the shadow fading,path loss and Rayleigh fading are all considered. Our aim is to maximize the EE which is defined as the ratio of the transmission rate to the total consumed power subject to the maximum transmit power of each remote antenna constraint and Qo S(target BER) requirement. According to the definition of EE and using the upper bound of average EE,the optimized objective function is provided. Based on this,utilizing Karush-KuhnTucker conditions and numerical calculation,a suboptimal energy efficient power allocation(PA) scheme is developed,and the closedform expression of PA coefficients is derived. The scheme may obtain the EE performance close to the existing optimal scheme. Moreover,it has relatively lower complexity than the existing scheme because only the statistic channel information and less iteration are required. Simulation results show the presented scheme is valid and can meet the target BER requirement,and the EE can be increased as target BER requirement decreases.展开更多
Ecosystem services are spatially heterogeneous and temporal variability, which results in trade-offs,synergies and neutrality. The trade-off is a key problem in ecosystem management and requires optimized decision-mak...Ecosystem services are spatially heterogeneous and temporal variability, which results in trade-offs,synergies and neutrality. The trade-off is a key problem in ecosystem management and requires optimized decision-making research. This paper reviews methods for identifying trade-offs and suggest future model developments. We conclude that(1) ecosystem service assessment depends on quantitative indicators and its modeling;(2)scenario analysis, multi-objective analysis and production possibility boundary are an effective means of ecosystem service trade-off decision-making;(3) future research needs to strengthen ecosystem service supply and demand flow and assist decision-making ecosystem mapping. Finally, integrated models should be developed to simulate and diagnose different scenarios and to optimize measures in land and ecosystem management for sustainability.展开更多
Traditional 802.11 power saving mechanism (PSM) treats multicast and broadcast traffic equally, and suffers sig-nificant performance degradation with multicast background traffic. This paper proposes an enhanced PSM t...Traditional 802.11 power saving mechanism (PSM) treats multicast and broadcast traffic equally, and suffers sig-nificant performance degradation with multicast background traffic. This paper proposes an enhanced PSM that effectively dif-ferentiates multicast streams. It re-arranges the virtual bitmap of the traffic indication map (TIM) to carry traffic status for mul-ticast groups and introduces a concept of sequential transmission of multi-addressed data to facilitate differentiation among mul-ticast groups. Our analysis shows that the enhanced PSM can effectively save power in mixed traffic environments.展开更多
基金The National Natural Science Foundation of China(No60673054,90412012)
文摘To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated QoS-aware job dispatching policy is proposed, which correlates priorities of incoming jobs used for job selecting at the local scheduler of the grid node with the job dispatching policies at the global scheduler for computational grids. The stochastic high-level Petri net (SHLPN) model of a two-level hierarchy computational grid architecture is presented, and a model refinement is made to reduce the complexity of the model solution. A performance analysis technique based on the SHLPN is proposed to investigate the QoS-aware job scheduling policy. Numerical results show that the QoS-aware job dispatching policy outperforms the QoS-unaware job dispatching policy in balancing the high-priority jobs, and thus enables priority-based QoS.
基金Supported by the Foundation of National Natural Science of China(60802005,50803016)the Science Foundation for the Excellent Youth Scholars in East China University of Science and Technology(YH0157127)the Undergraduate Innovational Experimentation Program in East China University of Science andTechnology(X1033)~~
文摘A heuristic theoretical optimal routing algorithm (TORA) is presented to achieve the data-gathering structure of location-aided quality of service (QoS) in wireless sensor networks (WSNs). The construction of TORA is based on a kind of swarm intelligence (SI) mechanism, i. e. , ant colony optimization. Firstly, the ener- gy-efficient weight is designed based on flow distribution to divide WSNs into different functional regions, so the routing selection can self-adapt asymmetric power configurations with lower latency. Then, the designs of the novel heuristic factor and the pheromone updating rule can endow ant-like agents with the ability of detecting the local networks energy status and approaching the theoretical optimal tree, thus improving the adaptability and en- ergy-efficiency in route building. Simulation results show that compared with some classic routing algorithms, TORA can further minimize the total communication energy cost and enhance the QoS performance with low-de- lay effect under the data-gathering condition.
基金supported by the National High-Tech R&D Program (863 Program2015AA01A705)in part by Beijing Municipal Commission of Education (The City's Vehicle Sensing Grid Construction Based on Public Transportation Network)
文摘This paper investigates on the base stations(BSs) sleeping control and energy saving in wireless network. The objective is to find the sleeping control and energy saving configuration between total power consumption and average video's quality. On the Software Defined Network(SDN) access network architecture, a type of sleeping control and active BSs' optimal transmitting time strategy is considered, the BS sleeps when there is no active users, and wakes up after a period of vacation time. In this paper, we study the active users grouping strategy, In order to spare more BSs into sleeping mode. Then this paper proposes an active BS transmitting time optimal strategy according to the users' Qo S. In the proposed strategy, the active BSs' transmitting time is minimized in order to save energy. This paper employs the mixed integer-programming model to present this optimization problem. Then we utilized a novel algorithm to save the energy in access networks and also meet the Qo S requirements. Both the analytical and simulation results show that the algorithm can effectively save energy in the access network BSs.
基金supported in part by the project of National Natural Science Foundation of China under Grant No. 61071075National Science and Technology Major Project of China under Grant No. 2010ZX03003-001-02+1 种基金National Science and Technology Major Project of China under Grant No. 2011ZX03004003the Chinese Ministry of Education in the project of the Fundamental Research Funds for the Central Universities under Grant No.2011YJS216
文摘Based on the cross-layer design, the power-optimization problem of Macro-Femto Heterogeneous Networks (HetNets) has been formulated. The constraints of power and re-source block allocation in the physical layer, delay and target data rate in the medium ac-cess control layer, urgent queue length in the network layer, and packet error rate in the transport layer, have been considered. The original problem is non-deterministic polyno-mial time hard, which cannot be solved practi-cally. After the restrictions of upper layers are translated into constraints with physical layer parameters, and the integer restrictions are relaxed, the original problem can be decom- posed into convex optimization subproblems. The optimal solutions of resource block allo-cation and power allocation can be obtained by using the Lagrangian optimization. Simula-tion results show that the proposed scheme is better than both the round robin algorithm and the max-rain one in terms of energy efficiency, throughput and service fairness. The round robin algorithm and the max-min one only focus on the user fairness rather than quality of service fairness. Compared to the round robin scheme (the max-min one), the proposed scheme improves the energy efficiency 58.85% (62.41%), the throughput 19.09% (25.25%), the service fairness 57.69% (35.48%).
文摘The power of employees is usually under estimated by managers in an organization. In order to achieve effectively the organizational objectives and compete externally, leaders must appreciate the importance of the employees and help them to do right things to the organization. The process to develop powerful employees, enhance a learning culture and recognize the achievements is the important element to employee satisfaction. The winner of the 21st century is the one who can understand and apply the strategy of people.
基金Supported by Anhui Environment Protection Scientific Research Program in 2014(201404)~~
文摘[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [Method] The val- ues of ecosystem function was estimated by market value method, opportunity cost approach, replacement cost method, shadow engineering approach, travel cost method, hedonic pricing method and contingent value method. [Result] With wetland ecosystem service function value totals 4.968 billion yuan, the value of eco-environ- ment regulation and maintenance was the highest, followed by the value of cultural and social function. The value of material production was the least. The values of sub-functions can be concluded by comparison of service function va}ue and pro- portions, as follows: flood mitigation 〉water purification 〉water conservation 〉 tourism&leisure〉material production〉scientific research and education〉water supply〉 biodiversity maintenance〉regulation on atmosphere constituents. [Conclusion] The re- search performed quantitative evaluations on ecosystem service function values of wetlands in Chao Lake and is of significance for specific development and protec- tion of local wetlands.
基金supported by the State Grid Technology Project of China(SGIT0000 KJJS1500008)
文摘Cognitive radio sensor network is applied to facilitate network monitoring and management, and achieves high spectrum efficiencies in smart grid. However, the conventional traffic scheduling mechanisms are hard to provide guaranteed quality of service for the secondary users. It is because that they ignore the influence of diverse transition requirements in heterogeneous traffi c. Therefore, a novel Qo S-aware packet scheduling mechanism is proposed to improve transmission quality for secondary users. In this mechanism, a Qo S-based prioritization model is established to address data classification firstly. And then, channel quality and the effect of channel switch are integrated into priority-based packet scheduling mechanism. At last, the simulation is implemented with MATLAB and OPNET. The results show that the proposed scheduling mechanism improves the transmission quality of high-priority secondary users and increase the whole system utilization by 10%.
文摘This paper resumes a research project developed in the concession area of AES Eletropaulo, the largest electrical energy distribution company in Brazil. First, the global standards of information exchange within power transmission and distribution area were evaluated, allowing the definition of state of the art on the theme, followed by determining its applications considering technologies already applied by the company. The specifications needed for the generation of a data integration model are adapted to radial overhead network at company concession area. The project developed an intermediary connectivity layer, based on the CIM (common information model), which enables corporative systems to communicate in a standard way, through the use of integrating technologies. It, therefore, enabled modeling all main subjects of an electrical network in an open, extensible and non-proprietary way, in a model that contains classes and attributes of such subjects, as well as their relationships. Calculation and planning products adopted by the company were integrated to the technological layer implemented.
文摘Advanced Metering Infrastructure (AMI) enables smart grids to involve power consumers in the business process of power generation transmission, distribution and consumption. However, the participant of consumers challenges the current power systems with system integration and cooperation and security issues. In this paper, the authors introduce a service-oriented approach to AMI aiming at solving the intercommunication problem and meanwhile providing a trust and secure environment for smart grids. In this approach heterogeneous systems expose services to the network. System integration and cooperation are done through service composition. A generic service interfacing method is designed to develop standardized services for heterogeneous power systems. Moreover, role-based access control mechanism is used to guarantee the secure access to smart grids. With the seamless communication between consumers and power systems and among power systems themselves, this service-oriented AMI can associate consumers with actual system workload and furthermore support the intelligent running of power systems.
基金supported by the Natural Science Foundation of China (71103021, 71573022, 71372193, 71301106)Beijing Philosophy and Social Science Planning Foundation (13JGC085)+1 种基金Beijing Higher Education Yong Elite Teacher Foundation (YETP0852)Humanities and Social Sciences Foundation of the Ministry of Education(13YJC630034, 13YJA790023)
文摘Standard e-government information system(SEIS) including mobile-government applications are playing more and more important roles in the establishing of national e-government framework. It can be beneficial not only for avoiding redundant e-government IS development but also for improving collaboration among government agencies. Two research questions were explored: what are the factors influencing the performance of SEIS? Will mandatory SEIS create a better performance than non-mandatory SEIS? Specifically, the use of five categories of IS aspects--information system quality, online service quality, offline service quality, diffusion modes and standard network size—is proposed to understand the performance of SEIS through applying both survey study and simulation study. The results show that information system quality and online service quality of SEIS have strong effects on users' expectation and users' satisfaction, which thereafter promotes the performance of SEIS. Government agencies' offline service quality shows a significant effect on users' satisfaction while not on users' expectation. Furthermore, the diffusion speed of SEIS in non-mandatory and mandatory modes and the standard network size also have great influence on the utility of SEIS.
基金partially supported by National Natural Science Foundation of China (61571225)Research Founding of Graduate Innovation Center in NUAA (kfjj20150410)+4 种基金the Fundamental Research Funds for the Central Universities (NS2015046,NS2016044)Shenzhen Strategic Emerging Industry Development Funds (JSGG20150331160845693)Qing Lan Project of JiangsuSix Talent Peaks Project in Jiangsu (DZXX-007)Open Research Fund of National Mobile Communications Research Laboratory of Southeast University (2012D17)
文摘The energy efficiency(EE) of distributed antenna system with quality of service(Qo S) requirement is investigated over composite Rayleigh fading channel,where the shadow fading,path loss and Rayleigh fading are all considered. Our aim is to maximize the EE which is defined as the ratio of the transmission rate to the total consumed power subject to the maximum transmit power of each remote antenna constraint and Qo S(target BER) requirement. According to the definition of EE and using the upper bound of average EE,the optimized objective function is provided. Based on this,utilizing Karush-KuhnTucker conditions and numerical calculation,a suboptimal energy efficient power allocation(PA) scheme is developed,and the closedform expression of PA coefficients is derived. The scheme may obtain the EE performance close to the existing optimal scheme. Moreover,it has relatively lower complexity than the existing scheme because only the statistic channel information and less iteration are required. Simulation results show the presented scheme is valid and can meet the target BER requirement,and the EE can be increased as target BER requirement decreases.
基金National Key Research and Development Program of China(2017YFC0503803)National Natural Science Foundation of China(41867012)Qinghai Province Science and Technology Basic Condition Platform Construction Special Project(2018-ZJ-T09)
文摘Ecosystem services are spatially heterogeneous and temporal variability, which results in trade-offs,synergies and neutrality. The trade-off is a key problem in ecosystem management and requires optimized decision-making research. This paper reviews methods for identifying trade-offs and suggest future model developments. We conclude that(1) ecosystem service assessment depends on quantitative indicators and its modeling;(2)scenario analysis, multi-objective analysis and production possibility boundary are an effective means of ecosystem service trade-off decision-making;(3) future research needs to strengthen ecosystem service supply and demand flow and assist decision-making ecosystem mapping. Finally, integrated models should be developed to simulate and diagnose different scenarios and to optimize measures in land and ecosystem management for sustainability.
基金Project (Nos. 60574087 and 60721003) supported by the National Natural Science Foundation of China
文摘Traditional 802.11 power saving mechanism (PSM) treats multicast and broadcast traffic equally, and suffers sig-nificant performance degradation with multicast background traffic. This paper proposes an enhanced PSM that effectively dif-ferentiates multicast streams. It re-arranges the virtual bitmap of the traffic indication map (TIM) to carry traffic status for mul-ticast groups and introduces a concept of sequential transmission of multi-addressed data to facilitate differentiation among mul-ticast groups. Our analysis shows that the enhanced PSM can effectively save power in mixed traffic environments.