Renewable energy (RE) has been attached high attention around the world due to its carbon-free and indigenous production in a sustainable way. China enjoys plenty of renewable energy resources, particularly the wind, ...Renewable energy (RE) has been attached high attention around the world due to its carbon-free and indigenous production in a sustainable way. China enjoys plenty of renewable energy resources, particularly the wind, solar, hydro- and biomass energy, which could be a sound basis for a large-scale exploitation. This report examines the current status of RE technology and industry, analyzes the challenges of promoting RE in China. In order to pave the way for a long-term development of RE, this paper outlines the basic principles and priorities for individual RE technology. In line with these, the paper puts forward the RE targets and further describes the RE road map by 2020, 2030 and extend to 2050, taking consideration of China’s RE resources, industrial basis and energy demand etc. At last, this paper provides some recommendations to ensure the achievements of the RE targets.展开更多
Positive development of renewable energy, saving and substitution of fossil energy, promotion of the energy structure adjustment are the inevitable strategy choices of China’s sustainable development. This paper disc...Positive development of renewable energy, saving and substitution of fossil energy, promotion of the energy structure adjustment are the inevitable strategy choices of China’s sustainable development. This paper discussed the China’s bioenergy resources status, development targets and technology development roadmaps. China has 136.140 million hm2 of marginal land, which distribute mainly in western and northern regions. There are 1 billion t of crop residues and forestry waste annually, and 300 million t can be used to produce different kinds of bioenergies. And organic waste and manure can generate 50 billion m3 of biogas. The discussed development target indicated that it can construct a biomass oilfield with the capacity of 100 million t/year and reduce 200 million t of CO_2 emission by 2020. The bioenergy technology development roadmap indicated that the bioethanol mainly uses non grain starch and hemicellulose products as raw materials in the near-term (2006-2010). The biodiesel technology will focus on the advanced production technology, FT diesel, liquefaction of biomass and raw material production technology.展开更多
Wireless Mesh Networks （WMNs） have many applications in homes, schools, enterprises, and public places because of their useful characteristics, such as high bandwidth, high speed, and wide coverage. However, the sec...Wireless Mesh Networks （WMNs） have many applications in homes, schools, enterprises, and public places because of their useful characteristics, such as high bandwidth, high speed, and wide coverage. However, the security of wireless mesh networks is a precondition for practical use. Intrusion detection is pivotal for increasing network security. Considering the energy limitations in wireless mesh networks, we adopt two types of nodes： Heavy Intrusion Detection Node （HIDN） and Light Intrusion Detection Node （LIDN）. To conserve energy, the LIDN detects abnorrml behavior according to probability, while the HIDN, which has sufficient energy, is always operational. In practice, it is very difficult to acquire accurate information regarding attackers. We propose an intrusion detection model based on the incomplete inforrmtion game （ID-IIG）. The ID-IIG utilizes the Harsanyi transformation and Bayesian Nash equilibrium to select the best strategies of defenders, although the exact attack probability is unknown. Thus, it can effectively direct the deployment of defenders. Through experiments, we analyze the perforrmnce of ID-IIG and verify the existence and attainability of the Bayesian Nash equilibrium.展开更多
In this paper,we discuss in detail the basic issue of green design and consider an energy efficiency function as the metric to evaluate green cellular networks.Specifically,we investigate the transmit power required f...In this paper,we discuss in detail the basic issue of green design and consider an energy efficiency function as the metric to evaluate green cellular networks.Specifically,we investigate the transmit power required for an expected transmission capacity and propose a capacity-power formula based on the energy conservation and the Shannon capacity theorem.Two novel definitions of cell interference depth and handoff dynamic model are introduced and the corresponding expression of energy efficiency function is derived.Numerical results show that the energy efficiency function is closely correlated with the transmitted/received power required and the cell radius.Our work provides a useful basis for research and evaluation on green design and technology of cellular networks.展开更多
With the explosive growth and need for high-speed wireless communications, more and more energy is consumed to support the required quality of service. Therefore, energy efficient or green communication has become a v...With the explosive growth and need for high-speed wireless communications, more and more energy is consumed to support the required quality of service. Therefore, energy efficient or green communication has become a very hot topic under the ground of limited energy resource and environmentally friendly transmission schemes. MIMO technique is capable of reducing the transmission power thanks to its diversity and multiplexing gain. Moreover, antenna selection(AS) is an alternative to extract many of the benefits in MIMO systems with a reduced cost of complexity and power. Although many works including several survey papers have investigated AS in MIMO systems, the goal of these works is only the capacity maximization or error rate minimization, which fails to guarantee the optimality of the energy efficiency in MIMO systems. In this paper, we overview the state of the art in the AS schemes in energy efficient MIMO systems, the goal of which is to optimize the energy efficiency of the whole system. Specifically, we introduce energy efficient AS in point-to-point MIMO, cooperative MIMO, multiuser MIMO and largescale MIMO systems, respectively. Several challenging and practical issues in this area are also addressed.展开更多
In this paper we construct a theoretical framework linking governance practiced by some countries to some of their economical, financial, social and environmental variables. To achieve this goal, we selected a sample ...In this paper we construct a theoretical framework linking governance practiced by some countries to some of their economical, financial, social and environmental variables. To achieve this goal, we selected a sample of data composed of variables from 55 countries, available at the World Bank website. On the other hand, we measured the countries＇ level of governance by the indicator promoted by Transparency International. The period considered in this research was 8 years, from 2000 to 2008. We used the method of linear regression with panel data, in order to investigate statistical relationships among governance and the other variables. We applied the method of simultaneous equations in order to make a robustness test on the first results and findings. The results of the two models converged and showed the existence of a statistical significant relationship between governance and several of the variables investigated. This allows us to infer that the development of the countries govemanee is closely linked with the long-term sustainable development.展开更多
Wireless Body Area Network(WBAN) is the most promising technology in e-health applications.Energy efficiency stands out as the paramount issue for WBAN.In this paper,an energy efficient MAC protocol named Quasi-Sleep-...Wireless Body Area Network(WBAN) is the most promising technology in e-health applications.Energy efficiency stands out as the paramount issue for WBAN.In this paper,an energy efficient MAC protocol named Quasi-Sleep-Preempt-Supported(QSPS) is proposed.The protocol is mainly TDMA-based:nodes transmit packets in the allocated slots,while entering the Q-Sleep mode in other slots.Moreover,for a node with emergency packet,it can broadcast a special designed Awakening Message to wake up the whole network and preempts the right to use the current slot to transmit that emergency packet,thus decreasing delay.Compared with relevant protocols,QS-PS can achieve high energy efficiency and decrease the delay of both normal packets and emergency packets.展开更多
In order to resolve the relay selection problem in wireless mobile relay networks （WMRNs）, a novel balanced energy-efficient mobile relay selection scheme is proposed in this paper. Compared with traditional counter...In order to resolve the relay selection problem in wireless mobile relay networks （WMRNs）, a novel balanced energy-efficient mobile relay selection scheme is proposed in this paper. Compared with traditional counter-based algorithm, distance and energy consumption are considered from network respect to provide a better network lifetime performance in the proposed scheme. Also, it performs well when nodes move freely at high speed. A random assessment delay （RAD） mechanism is added to avoid collisions and improve transmission efficiency. Simulation results reveal that, the proposed scheme has advantages in prolonging network lifetime, balancing energy compared with existing counter-based scheme. consumption and reducing the total energy consumption展开更多
The quality of methods for determining energy transits on the tie lines （lines that connect two neighboring power system） can have significant impact on business activity of the TSOs （transmission system operators...The quality of methods for determining energy transits on the tie lines （lines that connect two neighboring power system） can have significant impact on business activity of the TSOs （transmission system operators）. Existing law regulation is not enough precise regarding definition of methods for metering energy transits （energy interchanged between neighboring TSOs）. This paper analyses disadvantages of method for line losses metering with electric meters and suggests introduction of the measured value corrections.展开更多
A T-Q diagram based on entransy theory is applied to graphically and quantitatively describe the irreversibility of the heat transfer processes.The hot and cold composite curves can be obtained in the T-Q diagram.The ...A T-Q diagram based on entransy theory is applied to graphically and quantitatively describe the irreversibility of the heat transfer processes.The hot and cold composite curves can be obtained in the T-Q diagram.The entransy recovery and entransy dissipation that are affected by temperature differences can be obtained through the shaded area under the composite curves.The method for setting the energy target of the HENs in T-Q diagram based on entransy theory is proposed.A case study of the diesel oil hydrogenation unit is used to illustrate the application of the method.The results show that three different heat transfer temperature differences is 10 K,15 K and 20 K,and the entransy recovery is 5.498×10~7k W·K,5.377×10~7k W·K,5.257×10~7k W·K,respectively.And the entransy transfer efficiency is 92.29%,91.63%,90.99%.Thus,the energy-saving potential of the HENs is obtained by setting the energy target based on the entransy transfer efficiency.展开更多
Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy effic...Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy efficiency and the influence of lower carbon development.Since work exchange network is a significant part of energy recovery system,its optima design will have dramatically significant effect on energy consumption reduction in chemical process system.With an extension of the developed transshipment model in isothermal process,a novel step-wise methodology for synthesis of direct work exchange network(WEN)in adiabatic process involving heat integration is first proposed in this paper,where a nonlinear programming(NLP)model is formulated by regarding the minimum utility consumption as objective function and optimizing the initial WEN in accordance with the presented matching rules to get the optimized WEN configuration at first.Furthermore,we focus on the work exchange network synthesis with heat integration to attain the minimal total annual cost(TAC)with the introduction of heat-exchange equipment that is achieved by the following strategies in sequence:introducing heat-exchange equipment directly,adjusting the work quantity of the adjacent utility compressors or expanders,and approximating upper/lower pressure limits consequently to obtain considerable cost savings of expanders or compressors and work utility.Finally,a case taken from the literature is studied to illustrate the feasibility and effectiveness of the proposed method.展开更多
文摘Renewable energy (RE) has been attached high attention around the world due to its carbon-free and indigenous production in a sustainable way. China enjoys plenty of renewable energy resources, particularly the wind, solar, hydro- and biomass energy, which could be a sound basis for a large-scale exploitation. This report examines the current status of RE technology and industry, analyzes the challenges of promoting RE in China. In order to pave the way for a long-term development of RE, this paper outlines the basic principles and priorities for individual RE technology. In line with these, the paper puts forward the RE targets and further describes the RE road map by 2020, 2030 and extend to 2050, taking consideration of China’s RE resources, industrial basis and energy demand etc. At last, this paper provides some recommendations to ensure the achievements of the RE targets.
文摘Positive development of renewable energy, saving and substitution of fossil energy, promotion of the energy structure adjustment are the inevitable strategy choices of China’s sustainable development. This paper discussed the China’s bioenergy resources status, development targets and technology development roadmaps. China has 136.140 million hm2 of marginal land, which distribute mainly in western and northern regions. There are 1 billion t of crop residues and forestry waste annually, and 300 million t can be used to produce different kinds of bioenergies. And organic waste and manure can generate 50 billion m3 of biogas. The discussed development target indicated that it can construct a biomass oilfield with the capacity of 100 million t/year and reduce 200 million t of CO_2 emission by 2020. The bioenergy technology development roadmap indicated that the bioethanol mainly uses non grain starch and hemicellulose products as raw materials in the near-term (2006-2010). The biodiesel technology will focus on the advanced production technology, FT diesel, liquefaction of biomass and raw material production technology.
基金This work was partially supported by the National Natural Science Foundation of China under Cxants No. 61272451, No. 61103220, No. 61173154, No. 61173175 the National Critical Patented Projects in the next generation broadband wireless mobile communication network under Grant No. 2010ZX03006-001-01.
文摘Wireless Mesh Networks （WMNs） have many applications in homes, schools, enterprises, and public places because of their useful characteristics, such as high bandwidth, high speed, and wide coverage. However, the security of wireless mesh networks is a precondition for practical use. Intrusion detection is pivotal for increasing network security. Considering the energy limitations in wireless mesh networks, we adopt two types of nodes： Heavy Intrusion Detection Node （HIDN） and Light Intrusion Detection Node （LIDN）. To conserve energy, the LIDN detects abnorrml behavior according to probability, while the HIDN, which has sufficient energy, is always operational. In practice, it is very difficult to acquire accurate information regarding attackers. We propose an intrusion detection model based on the incomplete inforrmtion game （ID-IIG）. The ID-IIG utilizes the Harsanyi transformation and Bayesian Nash equilibrium to select the best strategies of defenders, although the exact attack probability is unknown. Thus, it can effectively direct the deployment of defenders. Through experiments, we analyze the perforrmnce of ID-IIG and verify the existence and attainability of the Bayesian Nash equilibrium.
基金the National Science Foundation of China，the Hi-Tech Research and Development Program of China of Mobile Internet
文摘In this paper,we discuss in detail the basic issue of green design and consider an energy efficiency function as the metric to evaluate green cellular networks.Specifically,we investigate the transmit power required for an expected transmission capacity and propose a capacity-power formula based on the energy conservation and the Shannon capacity theorem.Two novel definitions of cell interference depth and handoff dynamic model are introduced and the corresponding expression of energy efficiency function is derived.Numerical results show that the energy efficiency function is closely correlated with the transmitted/received power required and the cell radius.Our work provides a useful basis for research and evaluation on green design and technology of cellular networks.
基金supported by NSFC under grant No. 61322111 and No. 61401249the National Basic Research Program of China (973 Program) No. 2013CB336600+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP) under Grant No. 20130002120001Chuanxin Funding, and Beijing nova program No.Z121101002512051
文摘With the explosive growth and need for high-speed wireless communications, more and more energy is consumed to support the required quality of service. Therefore, energy efficient or green communication has become a very hot topic under the ground of limited energy resource and environmentally friendly transmission schemes. MIMO technique is capable of reducing the transmission power thanks to its diversity and multiplexing gain. Moreover, antenna selection(AS) is an alternative to extract many of the benefits in MIMO systems with a reduced cost of complexity and power. Although many works including several survey papers have investigated AS in MIMO systems, the goal of these works is only the capacity maximization or error rate minimization, which fails to guarantee the optimality of the energy efficiency in MIMO systems. In this paper, we overview the state of the art in the AS schemes in energy efficient MIMO systems, the goal of which is to optimize the energy efficiency of the whole system. Specifically, we introduce energy efficient AS in point-to-point MIMO, cooperative MIMO, multiuser MIMO and largescale MIMO systems, respectively. Several challenging and practical issues in this area are also addressed.
文摘In this paper we construct a theoretical framework linking governance practiced by some countries to some of their economical, financial, social and environmental variables. To achieve this goal, we selected a sample of data composed of variables from 55 countries, available at the World Bank website. On the other hand, we measured the countries＇ level of governance by the indicator promoted by Transparency International. The period considered in this research was 8 years, from 2000 to 2008. We used the method of linear regression with panel data, in order to investigate statistical relationships among governance and the other variables. We applied the method of simultaneous equations in order to make a robustness test on the first results and findings. The results of the two models converged and showed the existence of a statistical significant relationship between governance and several of the variables investigated. This allows us to infer that the development of the countries govemanee is closely linked with the long-term sustainable development.
基金supported in part by National Natural Science Foundation of China(NSFC,No.61325012,6171219,6122001,61202373)
文摘Wireless Body Area Network(WBAN) is the most promising technology in e-health applications.Energy efficiency stands out as the paramount issue for WBAN.In this paper,an energy efficient MAC protocol named Quasi-Sleep-Preempt-Supported(QSPS) is proposed.The protocol is mainly TDMA-based:nodes transmit packets in the allocated slots,while entering the Q-Sleep mode in other slots.Moreover,for a node with emergency packet,it can broadcast a special designed Awakening Message to wake up the whole network and preempts the right to use the current slot to transmit that emergency packet,thus decreasing delay.Compared with relevant protocols,QS-PS can achieve high energy efficiency and decrease the delay of both normal packets and emergency packets.
基金Supported by the National High Technology Research and Development Programme of China （No. 2007AA01Z221, 2009AA01Z246） and the National Natural Science Foundation of China （No. 60832009）.
文摘In order to resolve the relay selection problem in wireless mobile relay networks （WMRNs）, a novel balanced energy-efficient mobile relay selection scheme is proposed in this paper. Compared with traditional counter-based algorithm, distance and energy consumption are considered from network respect to provide a better network lifetime performance in the proposed scheme. Also, it performs well when nodes move freely at high speed. A random assessment delay （RAD） mechanism is added to avoid collisions and improve transmission efficiency. Simulation results reveal that, the proposed scheme has advantages in prolonging network lifetime, balancing energy compared with existing counter-based scheme. consumption and reducing the total energy consumption
文摘The quality of methods for determining energy transits on the tie lines （lines that connect two neighboring power system） can have significant impact on business activity of the TSOs （transmission system operators）. Existing law regulation is not enough precise regarding definition of methods for metering energy transits （energy interchanged between neighboring TSOs）. This paper analyses disadvantages of method for line losses metering with electric meters and suggests introduction of the measured value corrections.
基金Supported by the National Natural Science Foundation of China(21406124)
文摘A T-Q diagram based on entransy theory is applied to graphically and quantitatively describe the irreversibility of the heat transfer processes.The hot and cold composite curves can be obtained in the T-Q diagram.The entransy recovery and entransy dissipation that are affected by temperature differences can be obtained through the shaded area under the composite curves.The method for setting the energy target of the HENs in T-Q diagram based on entransy theory is proposed.A case study of the diesel oil hydrogenation unit is used to illustrate the application of the method.The results show that three different heat transfer temperature differences is 10 K,15 K and 20 K,and the entransy recovery is 5.498×10~7k W·K,5.377×10~7k W·K,5.257×10~7k W·K,respectively.And the entransy transfer efficiency is 92.29%,91.63%,90.99%.Thus,the energy-saving potential of the HENs is obtained by setting the energy target based on the entransy transfer efficiency.
基金Supported by the National Natural Science Foundation of China(21576036,21406026)
文摘Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy efficiency and the influence of lower carbon development.Since work exchange network is a significant part of energy recovery system,its optima design will have dramatically significant effect on energy consumption reduction in chemical process system.With an extension of the developed transshipment model in isothermal process,a novel step-wise methodology for synthesis of direct work exchange network(WEN)in adiabatic process involving heat integration is first proposed in this paper,where a nonlinear programming(NLP)model is formulated by regarding the minimum utility consumption as objective function and optimizing the initial WEN in accordance with the presented matching rules to get the optimized WEN configuration at first.Furthermore,we focus on the work exchange network synthesis with heat integration to attain the minimal total annual cost(TAC)with the introduction of heat-exchange equipment that is achieved by the following strategies in sequence:introducing heat-exchange equipment directly,adjusting the work quantity of the adjacent utility compressors or expanders,and approximating upper/lower pressure limits consequently to obtain considerable cost savings of expanders or compressors and work utility.Finally,a case taken from the literature is studied to illustrate the feasibility and effectiveness of the proposed method.
