With the wide application of renewable energy power generation technology,the distribution network presents the characteristics of multi-source and complex structure.There are potential risks in the stability of power...With the wide application of renewable energy power generation technology,the distribution network presents the characteristics of multi-source and complex structure.There are potential risks in the stability of power system,and the problem of power quality is becoming more and more serious.This paper studies and proposes a power optimization cooperative control strategy for flexible fast interconnection device with energy storage,which combines the flexible interconnection technology with the energy storage device.The primary technology is to regulate the active and reactive power of the converter.By comparing the actual power value of the converter with the reference value,the proportional integral(PI)controller is used for correction,and the current components of d and q axes are obtained and input to the converter as the reference value of the current inner loop.The control strategy in this paper can realize power mutual aid between feeders,and at the same time,the energy storage device can provide or absorb a certain amount of power for feeders,so that the power grid can realize stable operation in a certain range.展开更多
Energy-efficient communications is crucial for wireless sensor networks(WSN) where energy consumption is constrained. The transmission and reception energy can be saved by applying network coding to many wireless comm...Energy-efficient communications is crucial for wireless sensor networks(WSN) where energy consumption is constrained. The transmission and reception energy can be saved by applying network coding to many wireless communications systems. In this paper,we present a coded cooperation scheme which employs network coding to WSN. In the scheme,the partner node forwards the combination of the source data and its own data instead of sending the source data alone. Afterward,both of the system block error rates(BLERs) and energy performance are evaluated. Experiment results show that the proposed scheme has higher energy efficiency. When Noise power spectral density is-171dBm/Hz,the energy consumption of the coded cooperation scheme is 81.1% lower than that of the single-path scheme,43.9% lower than that of the cooperation scheme to reach the target average BLER of 10-2. When the channel condition is getting worse,the energy saving effect is more obvious.展开更多
For acquiring high energy efficiency and the maximal throughput, a new time slot structure is designed for energy harvesting(EH) cognitive radio(CR). Considering the CR system with EH and cooperative relay, a best coo...For acquiring high energy efficiency and the maximal throughput, a new time slot structure is designed for energy harvesting(EH) cognitive radio(CR). Considering the CR system with EH and cooperative relay, a best cooperative mechanism(BCM)is proposed for CR with EH. To get the optimal estimation performance, a quantum fireworks algorithm(QFA) is designed to resolve the difficulties of maximal throughput and EH, and the proposed cooperative mechanism is called as QFA-BCM. The proposed QFA combines the advantages of quantum computation theory with the fireworks algorithm(FA). Thus the QFA is able to obtain the optimal solution and its convergence performance is proved. By using the new cooperation mechanism and computing algorithm, the proposed QFA-BCM method can achieve comparable maximal throughput in the new timeslot structure. Simulation results have proved that the QFA-BCM method is superior to previous non-cooperative and cooperative mechanisms.展开更多
With the release of the electricity sales side,large-scale small-capacity distributed power generation units are connected to the distribution side,forming multi-type market entities such as microgrids,integrated ener...With the release of the electricity sales side,large-scale small-capacity distributed power generation units are connected to the distribution side,forming multi-type market entities such as microgrids,integrated energy systems,and virtual power plants.With the large-scale integration of distributed energy,the energy market under the energy internet is different from a traditional transmission grid.It is currently developing in the direction of diversified entities and commodities,a flat structure,and a flexible and competitive multi-agent market mechanism.In this context,this study analyzes the value of combining blockchain and the electricity market presents the design of a blockchain trading framework for multi-agent cooperation and sharing of the energy internet.The nodes in market transactions are modeled through power system modeling in the physical layer and the transaction consensus strategy in the cyber layer;moreover,the nodes are verified in a modified IEEE 13 testing feeder of a distribution network.A transaction example is demonstrated using the multi-agent cooperation and sharing transaction platform based on the Ethereum private blockchain.展开更多
In terms of energy supply, the Belt and Road Initiative has accelerated China’s international cooperation and has shaped, via that cooperation, the focus upon clean energy and low-carbon innovation.Under the Belt and...In terms of energy supply, the Belt and Road Initiative has accelerated China’s international cooperation and has shaped, via that cooperation, the focus upon clean energy and low-carbon innovation.Under the Belt and Road framework, the market will play an increased role as multilateral organizations engage in new models of international energy cooperation. As the largest energy consumer and public goods provider, China’s transition in energy cooperation will profoundly impact regional energy security and development. The economic growth of partners will also enhance results.展开更多
In this paper, the evolution of the energy use by human society is discussed, relating the energy, environmental and economic crisis, which appear to be closely linked. With the widespread use of fossil fuels since th...In this paper, the evolution of the energy use by human society is discussed, relating the energy, environmental and economic crisis, which appear to be closely linked. With the widespread use of fossil fuels since the industrial revolution, a major environmental problem was generated: the climate changes. The economic consequences of climate changes are discussed in Stern (2006). Possible solutions to confront climate change are presented in the Intergovernmental Panel on Climate Change (IPCC) report (2007). Some of these solutions are based on technological development, while others do not directly depend on the technology (paradigm shifts). Faced with the needs of a new paradigm suggested by the IPCC, the recent concept of sustainable triangular cells (2012) was introduced. The geometric representation of triangular cells, which can be linked to form a regular hexagon, is used to demonstrate a sustainable society, where human cooperation prevails. This model is in line with one of the pillars of the Third Industrial Revolution, indicated by Rifkin, where an intense collaboration between individuals in human society is suggested.展开更多
Purpose–To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure,...Purpose–To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure,energy-saving performance of the whole metro system cannot be guaranteed.Design/methodology/approach–A cooperative train control framework is formulated to regulate a novel train operation mode.The classic train four-phase control strategy is improved for generating specific energy-efficient control schemes for each train.An improved brute force(BF)algorithm with a two-layer searching idea is designed to solve the optimisation model of energy-efficient train control schemes.Findings–Case studies on the actual metro line in Guangzhou,China verify the effectiveness of the proposed train control methods compared with four-phase control strategy under different kinds of train operation scenarios and calculation parameters.The verification on the computation efficiency as well as accuracy of the proposed algorithm indicates that it meets the requirement of online optimisation.Originality/value–Most existing studies optimised energy-efficient train timetable or train control strategies through an offline process,which has a defect in coping with the disturbance or delays effectively and promptly during real-time train operation.This paper studies an online optimisation of cooperative train control based on the rolling optimisation idea,where energy-efficient train operation can be realised once train running time is determined,thus mitigating the impact of unpredictable operation situations on the energy-saving performance of trains.展开更多
On January 18,“China International Energy Cooperation Forum 2018:New Era,New Opportunities,New Vision and New Ideas”was successfully held on the campus of its organizer Renmin University of China.This forum received...On January 18,“China International Energy Cooperation Forum 2018:New Era,New Opportunities,New Vision and New Ideas”was successfully held on the campus of its organizer Renmin University of China.This forum received strong support from dozens of domestic and foreign research institutes,including the Renewable Energy Professional Committee of China Energy Research Society,Resource and Environmental Policy Institute of the Development Research Center of the State Council,the International Energy Research Institute of the International Cooperation Center of the National Development and Reform Commission,the CNPC Economics and Technological Research Institute,and the Center on Global Energy Policy of Columbia University.The forum was divided into four parts in two sessions of“Report Release”and“Expert Discussion”.Active and warm discussions were conducted around four topics:“The Position and Role of China in Global Energy Governance”,“The Potential Risks and Their Aversion in China’s International Energy Cooperation under the Belt and Road Initiative”,“How Can Chinese Energy Companies Enhance Their Global Competitiveness”,and“How to Increase the Safety of Overseas Interests in China’s Foreign Energy Investments”.The discussions were unanimously acknowledged by the展开更多
With the rapid development and application of energy harvesting technology,it has become a prominent research area due to its significant benefits in terms of green environmental protection,convenience,and high safety...With the rapid development and application of energy harvesting technology,it has become a prominent research area due to its significant benefits in terms of green environmental protection,convenience,and high safety and efficiency.However,the uneven energy collection and consumption among IoT devices at varying distances may lead to resource imbalance within energy harvesting networks,thereby resulting in low energy transmission efficiency.To enhance the energy transmission efficiency of IoT devices in energy harvesting,this paper focuses on the utilization of collaborative communication,along with pricing-based incentive mechanisms and auction strategies.We propose a dynamic relay selection scheme,including a ladder pricing mechanism based on energy level and a Kuhn-Munkre Algorithm based on an auction theory employing a negotiation mechanism,to encourage more IoT devices to participate in the collaboration process.Simulation results demonstrate that the proposed algorithm outperforms traditional algorithms in terms of improving the energy efficiency of the system.展开更多
Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content deliver...Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, respectively.Simulation results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances.展开更多
Intelligent chatbots powered by large language models(LLMs)have recently been sweeping the world,with potential for a wide variety of industrial applications.Global frontier technology companies are feverishly partici...Intelligent chatbots powered by large language models(LLMs)have recently been sweeping the world,with potential for a wide variety of industrial applications.Global frontier technology companies are feverishly participating in LLM-powered chatbot design and development,providing several alternatives beyond the famous ChatGPT.However,training,fine-tuning,and updating such intelligent chatbots consume substantial amounts of electricity,resulting in significant carbon emissions.The research and development of all intelligent LLMs and software,hardware manufacturing(e.g.,graphics processing units and supercomputers),related data/operations management,and material recycling supporting chatbot services are associated with carbon emissions to varying extents.Attention should therefore be paid to the entire life-cycle energy and carbon footprints of LLM-powered intelligent chatbots in both the present and future in order to mitigate their climate change impact.In this work,we clarify and highlight the energy consumption and carbon emission implications of eight main phases throughout the life cycle of the development of such intelligent chatbots.Based on a life-cycle and interaction analysis of these phases,we propose a system-level solution with three strategic pathways to optimize the management of this industry and mitigate the related footprints.While anticipating the enormous potential of this advanced technology and its products,we make an appeal for a rethinking of the mitigation pathways and strategies of the life-cycle energy usage and carbon emissions of the LLM-powered intelligent chatbot industry and a reshaping of their energy and environmental implications at this early stage of development.展开更多
Energy security is an issue that many countries pay more attention to. Cooperation is a good way to solute it. According to the complex system theory, the regional energy cooperation means a state or process of balanc...Energy security is an issue that many countries pay more attention to. Cooperation is a good way to solute it. According to the complex system theory, the regional energy cooperation means a state or process of balance system formed by the interaction and behavior coordination between agents. The features of the regional energy cooperation risk include: uncertainty, potential, fuzziness, diversity, relevance and particularity. And the regional energy cooperation risk can be divided into risk inside the system such as main body ability structure of the risk and main body decision-making risk, and the risk outside the system such as external environment factors and cooperation pattern factors.展开更多
This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node ind...This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node individually employing traditional automatic-repeat-request(ARQ) protocol.We propose a practical node cooperation(NC) protocol to enhance the collection efficiency,utilizing the fact that underwater nodes can overhear the transmission of others.To reduce the source level of underwater nodes,the underwater data collection area is divided into several sub-zones,and in each sub-zone,the mobile surface node adopting the NC protocol could switch adaptively between selective relay cooperation(SRC) and dynamic network coded cooperation(DNC) .The difference of SRC and DNC lies in whether or not the selected relay node combines the local data and the data overheard from undecoded node(s) to form network coded packets in the retransmission phase.The NC protocol could also be applied across the sub-zones due to the wiretap property.In addition,we investigate the effects of different mobile collection paths,collection area division and cooperative zone design for energy saving.The numerical results showthat the proposed NC protocol can effectively save energy compared with the traditional ARQ scheme.展开更多
Minerals and resources trade and investment play a pivotal role in economic and trade relations between China and Australia.In recent years,although China-Australia political relations have been at a low point,China?A...Minerals and resources trade and investment play a pivotal role in economic and trade relations between China and Australia.In recent years,although China-Australia political relations have been at a low point,China?Australia minerals and energy cooperation has exhibited a different trend to that of political relations,and also from the engagement during previous periods.Minerals and energy trade has increased steadily,while investment is becoming more difficult,particularly for large projects.There has been a clear green transition in trade and investment in this functional area,and uncertainty has increased due to the influence of factors such as the Belt and Road Initiative(BRI),the shale gas revolution and China-US trade disputes.Because this is one of the pillars for economic growth for both countries,and for their trade and investment ties,and because of the importance of low-carbon transition,the free trade system,and global and regional governance,minerals and energy cooperation can serve as a platform for improving and promoting bilateral relations.It has been suggested that China should seize the opportunity to improve bilateral relations by deepening two-way investment,joining hands with Australia on developing more products in more areas,and with new cooperation models.This research will be significant for understanding the status quo of China-Australia cooperation in minerals and energy,and for improving bilateral relations,and even international energy governance.展开更多
This paper explores the incentives of investment in renewable energy of two utility firms who compete or cooperate under either a cap-and-trade grandfathering mechanism(GM)or benchmarking mechanism(BM).We find that ut...This paper explores the incentives of investment in renewable energy of two utility firms who compete or cooperate under either a cap-and-trade grandfathering mechanism(GM)or benchmarking mechanism(BM).We find that utility firms will invest in renewable energy more under BM than under GM,in both competitive and cooperative markets,and they will invest more in a competitive market than in a cooperative market,under either GM or BM.Furthermore,utility firms will produce more electricity and generate more total carbon emissions under BM than under GM.The profits of two firms,however,are higher in cooperative market than in competitive market.The government will benefit from implementing a BM to encourage utility firms to invest in renewable energy in a competing market.展开更多
The "Belt and Road Initiative"was proposed by China in order to deepen international cooperation. The promotion of this initiative will have a positive and far-reaching impact on the sustainable development ...The "Belt and Road Initiative"was proposed by China in order to deepen international cooperation. The promotion of this initiative will have a positive and far-reaching impact on the sustainable development of China's economy.Energy cooperation has become an important part of China's opening up to the outside world. It is of great sign^cance in safeguarding national security,ensuring stable supply of energy,improving China's rights of speech in international energy markets,and helping China's energy companies to "go global".So far, energy cooperation along the Belt and Road has achieved a good start.Oil and gas companies such as CNPC and Sinopec have moved very fast in overseas cooperation,and new energy companies are actively following up.In order to achieve practical results in China's energy cooperation,this paper analyzesseveral problems and puts forward policy proposals.展开更多
Energy trade is the barometer of global trade in goods and plays an integral role international trade. As an important part of the implementation of the Belt and Road Initiative,multilateral partnership in energy trad...Energy trade is the barometer of global trade in goods and plays an integral role international trade. As an important part of the implementation of the Belt and Road Initiative,multilateral partnership in energy trade is one of the most cooperative and promising areas for the countries along the Belt and Road.Since the implementation of the initiative five years ago,cooperation in energy trade between China and the countries along the Belt and Road has been deepening.This development not only benefits the energy producers,energy consumers and energy corridors,but it also elevates China's influence and leadership in the regional energy market, contributing to the construction of a new international energy order.展开更多
Energy trade is the barometer of global trade in goods and plays an integral role international trade. As an important part of the implementation of the "Belt and Road"Initiative,multilateral partnership in ...Energy trade is the barometer of global trade in goods and plays an integral role international trade. As an important part of the implementation of the "Belt and Road"Initiative,multilateral partnership in energy trade is one of the most cooperative and promising areas for the countries along the "Belt and Road".Since the implementation of the initiative five years ago,cooperation in energy trade between China and the countries along the "Belt and Road"has been deepening.This development not only benefits the energy producers,energy consumers and energy corridors,but it also elevates China's influence and leadership in the regional energy market,contributing to the construction of a new international energy order.展开更多
The economic rise of the BRICS countries(Brazil, Russia, India, China and South Africa) is closely tied to global energy politics and their increased consumption of global energy. Energy cooperation is one of the main...The economic rise of the BRICS countries(Brazil, Russia, India, China and South Africa) is closely tied to global energy politics and their increased consumption of global energy. Energy cooperation is one of the main forces behind the development of BRICS. Looking forward, energy concerns will undoubtedly remain an important influencing force for the BRICS, shaping their domestic politics and international relations. The pursuit of oil and gas(China, India, and South Africa) to support economic development and the search for stable petroleum markets(Brazil and Russia) have shaped BRICS relations with other countries and regions. This article is trying to elaborate on the reasons why BRICS Energy cooperation is beneficial for its members; also, this article regards the main challenges hindering cooperation, analyzes BRICS energy cooperation through the use of SWOT analysis and muses potential strategic points for BRICS countries up until 2050.展开更多
Over the past two decades, as the main battlefield of China's international energy cooperation, countries along the Belt and Road have had good foundations in the foreign investment. Through China's efforts to...Over the past two decades, as the main battlefield of China's international energy cooperation, countries along the Belt and Road have had good foundations in the foreign investment. Through China's efforts to build the Belt and Road, energy cooperation has enjoyed first-mover advantages. Looking ahead, the countries along the Belt and Road are predicted to enjoy a promising future in energy cooperation because of their abundant energy resources, their role as complements to China's economic development, and their vast amounts of cooperation potential. At the same time, we are also keenly aware that there are a number of risks caused by geopolitics, policy changes, price fluctuations and legal compliance in energy cooperation among the countries along the Belt and Road. Moreover, it is urgent for Chinese enterprises to enhance their international capabilities. In this context, it is necessary to further maintain and make full use of their first-mover advantages and play a guiding and demonstrating role. Enterprises should actively adapt to new changes, while the government should make progress in policy coordination, facility connectivity, unimpeded trade, financed integration and people-to-people bonds, so as to keep deepening international energy cooperation and to build an energy silk road and a community with a shared future for energy.展开更多
基金Supported by Science and Technology Projects of State Grid Corporation of China(JF2021018).
文摘With the wide application of renewable energy power generation technology,the distribution network presents the characteristics of multi-source and complex structure.There are potential risks in the stability of power system,and the problem of power quality is becoming more and more serious.This paper studies and proposes a power optimization cooperative control strategy for flexible fast interconnection device with energy storage,which combines the flexible interconnection technology with the energy storage device.The primary technology is to regulate the active and reactive power of the converter.By comparing the actual power value of the converter with the reference value,the proportional integral(PI)controller is used for correction,and the current components of d and q axes are obtained and input to the converter as the reference value of the current inner loop.The control strategy in this paper can realize power mutual aid between feeders,and at the same time,the energy storage device can provide or absorb a certain amount of power for feeders,so that the power grid can realize stable operation in a certain range.
基金support in part from the National Natural Science Foundation of China (No. 60962002)the Program to Sponsor Teams for Innovation in the Construction of Talent Highlands in Guangxi Institutions of Higher Learning+1 种基金the Foundation of Guangxi Key Laboratory of Information and Communication (NO. 20904)the Scientific Research Foundation of Guangxi University (Grant No.XBZ091006)
文摘Energy-efficient communications is crucial for wireless sensor networks(WSN) where energy consumption is constrained. The transmission and reception energy can be saved by applying network coding to many wireless communications systems. In this paper,we present a coded cooperation scheme which employs network coding to WSN. In the scheme,the partner node forwards the combination of the source data and its own data instead of sending the source data alone. Afterward,both of the system block error rates(BLERs) and energy performance are evaluated. Experiment results show that the proposed scheme has higher energy efficiency. When Noise power spectral density is-171dBm/Hz,the energy consumption of the coded cooperation scheme is 81.1% lower than that of the single-path scheme,43.9% lower than that of the cooperation scheme to reach the target average BLER of 10-2. When the channel condition is getting worse,the energy saving effect is more obvious.
基金supported by the National Natural Science Foundation of China(61571149)the Special China Postdoctoral Science Foundation(2015T80325)+2 种基金the Heilongjiang Postdoctoral Fund(LBH-Z13054)the China Scholarship Council and the Fundamental Research Funds for the Central Universities(HEUCFP201772HEUCF160808)
文摘For acquiring high energy efficiency and the maximal throughput, a new time slot structure is designed for energy harvesting(EH) cognitive radio(CR). Considering the CR system with EH and cooperative relay, a best cooperative mechanism(BCM)is proposed for CR with EH. To get the optimal estimation performance, a quantum fireworks algorithm(QFA) is designed to resolve the difficulties of maximal throughput and EH, and the proposed cooperative mechanism is called as QFA-BCM. The proposed QFA combines the advantages of quantum computation theory with the fireworks algorithm(FA). Thus the QFA is able to obtain the optimal solution and its convergence performance is proved. By using the new cooperation mechanism and computing algorithm, the proposed QFA-BCM method can achieve comparable maximal throughput in the new timeslot structure. Simulation results have proved that the QFA-BCM method is superior to previous non-cooperative and cooperative mechanisms.
基金the Smart Grid Joint Fund of the National Natural Science Foundation of China(No.U2066209)the Science and Technology Project of the China Electric Power Research Institute(No.AI83-20-002).
文摘With the release of the electricity sales side,large-scale small-capacity distributed power generation units are connected to the distribution side,forming multi-type market entities such as microgrids,integrated energy systems,and virtual power plants.With the large-scale integration of distributed energy,the energy market under the energy internet is different from a traditional transmission grid.It is currently developing in the direction of diversified entities and commodities,a flat structure,and a flexible and competitive multi-agent market mechanism.In this context,this study analyzes the value of combining blockchain and the electricity market presents the design of a blockchain trading framework for multi-agent cooperation and sharing of the energy internet.The nodes in market transactions are modeled through power system modeling in the physical layer and the transaction consensus strategy in the cyber layer;moreover,the nodes are verified in a modified IEEE 13 testing feeder of a distribution network.A transaction example is demonstrated using the multi-agent cooperation and sharing transaction platform based on the Ethereum private blockchain.
文摘In terms of energy supply, the Belt and Road Initiative has accelerated China’s international cooperation and has shaped, via that cooperation, the focus upon clean energy and low-carbon innovation.Under the Belt and Road framework, the market will play an increased role as multilateral organizations engage in new models of international energy cooperation. As the largest energy consumer and public goods provider, China’s transition in energy cooperation will profoundly impact regional energy security and development. The economic growth of partners will also enhance results.
文摘In this paper, the evolution of the energy use by human society is discussed, relating the energy, environmental and economic crisis, which appear to be closely linked. With the widespread use of fossil fuels since the industrial revolution, a major environmental problem was generated: the climate changes. The economic consequences of climate changes are discussed in Stern (2006). Possible solutions to confront climate change are presented in the Intergovernmental Panel on Climate Change (IPCC) report (2007). Some of these solutions are based on technological development, while others do not directly depend on the technology (paradigm shifts). Faced with the needs of a new paradigm suggested by the IPCC, the recent concept of sustainable triangular cells (2012) was introduced. The geometric representation of triangular cells, which can be linked to form a regular hexagon, is used to demonstrate a sustainable society, where human cooperation prevails. This model is in line with one of the pillars of the Third Industrial Revolution, indicated by Rifkin, where an intense collaboration between individuals in human society is suggested.
基金This research was supported by the National Natural Science Foundation of China(Grant No.71971016).On behalf of all co-authors,the corresponding author states that there is no conflict of interest.
文摘Purpose–To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure,energy-saving performance of the whole metro system cannot be guaranteed.Design/methodology/approach–A cooperative train control framework is formulated to regulate a novel train operation mode.The classic train four-phase control strategy is improved for generating specific energy-efficient control schemes for each train.An improved brute force(BF)algorithm with a two-layer searching idea is designed to solve the optimisation model of energy-efficient train control schemes.Findings–Case studies on the actual metro line in Guangzhou,China verify the effectiveness of the proposed train control methods compared with four-phase control strategy under different kinds of train operation scenarios and calculation parameters.The verification on the computation efficiency as well as accuracy of the proposed algorithm indicates that it meets the requirement of online optimisation.Originality/value–Most existing studies optimised energy-efficient train timetable or train control strategies through an offline process,which has a defect in coping with the disturbance or delays effectively and promptly during real-time train operation.This paper studies an online optimisation of cooperative train control based on the rolling optimisation idea,where energy-efficient train operation can be realised once train running time is determined,thus mitigating the impact of unpredictable operation situations on the energy-saving performance of trains.
文摘On January 18,“China International Energy Cooperation Forum 2018:New Era,New Opportunities,New Vision and New Ideas”was successfully held on the campus of its organizer Renmin University of China.This forum received strong support from dozens of domestic and foreign research institutes,including the Renewable Energy Professional Committee of China Energy Research Society,Resource and Environmental Policy Institute of the Development Research Center of the State Council,the International Energy Research Institute of the International Cooperation Center of the National Development and Reform Commission,the CNPC Economics and Technological Research Institute,and the Center on Global Energy Policy of Columbia University.The forum was divided into four parts in two sessions of“Report Release”and“Expert Discussion”.Active and warm discussions were conducted around four topics:“The Position and Role of China in Global Energy Governance”,“The Potential Risks and Their Aversion in China’s International Energy Cooperation under the Belt and Road Initiative”,“How Can Chinese Energy Companies Enhance Their Global Competitiveness”,and“How to Increase the Safety of Overseas Interests in China’s Foreign Energy Investments”.The discussions were unanimously acknowledged by the
基金funded by the Researchers Supporting Project Number RSPD2024R681,King Saud University,Riyadh,Saudi Arabia.
文摘With the rapid development and application of energy harvesting technology,it has become a prominent research area due to its significant benefits in terms of green environmental protection,convenience,and high safety and efficiency.However,the uneven energy collection and consumption among IoT devices at varying distances may lead to resource imbalance within energy harvesting networks,thereby resulting in low energy transmission efficiency.To enhance the energy transmission efficiency of IoT devices in energy harvesting,this paper focuses on the utilization of collaborative communication,along with pricing-based incentive mechanisms and auction strategies.We propose a dynamic relay selection scheme,including a ladder pricing mechanism based on energy level and a Kuhn-Munkre Algorithm based on an auction theory employing a negotiation mechanism,to encourage more IoT devices to participate in the collaboration process.Simulation results demonstrate that the proposed algorithm outperforms traditional algorithms in terms of improving the energy efficiency of the system.
基金supported by National Natural Sciences Foundation of China(No.62271165,62027802,61831008)the Guangdong Basic and Applied Basic Research Foundation(No.2023A1515030297,2021A1515011572)Shenzhen Science and Technology Program ZDSYS20210623091808025,Stable Support Plan Program GXWD20231129102638002.
文摘Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, respectively.Simulation results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances.
基金supported by the National Natural Science Foundation of China(72061127004 and 72104164)the System Science and Enterprise Development Research Center(Xq22B04)+1 种基金financial support from the Engineering and Physical Sciences Research Council(EPSRC)Programme(EP/V030515/1)financial support from the Science and Technology Support Project of Guizhou Province([2019]2839).
文摘Intelligent chatbots powered by large language models(LLMs)have recently been sweeping the world,with potential for a wide variety of industrial applications.Global frontier technology companies are feverishly participating in LLM-powered chatbot design and development,providing several alternatives beyond the famous ChatGPT.However,training,fine-tuning,and updating such intelligent chatbots consume substantial amounts of electricity,resulting in significant carbon emissions.The research and development of all intelligent LLMs and software,hardware manufacturing(e.g.,graphics processing units and supercomputers),related data/operations management,and material recycling supporting chatbot services are associated with carbon emissions to varying extents.Attention should therefore be paid to the entire life-cycle energy and carbon footprints of LLM-powered intelligent chatbots in both the present and future in order to mitigate their climate change impact.In this work,we clarify and highlight the energy consumption and carbon emission implications of eight main phases throughout the life cycle of the development of such intelligent chatbots.Based on a life-cycle and interaction analysis of these phases,we propose a system-level solution with three strategic pathways to optimize the management of this industry and mitigate the related footprints.While anticipating the enormous potential of this advanced technology and its products,we make an appeal for a rethinking of the mitigation pathways and strategies of the life-cycle energy usage and carbon emissions of the LLM-powered intelligent chatbot industry and a reshaping of their energy and environmental implications at this early stage of development.
文摘Energy security is an issue that many countries pay more attention to. Cooperation is a good way to solute it. According to the complex system theory, the regional energy cooperation means a state or process of balance system formed by the interaction and behavior coordination between agents. The features of the regional energy cooperation risk include: uncertainty, potential, fuzziness, diversity, relevance and particularity. And the regional energy cooperation risk can be divided into risk inside the system such as main body ability structure of the risk and main body decision-making risk, and the risk outside the system such as external environment factors and cooperation pattern factors.
基金supported in part by National Key Research and Development Program of China under Grants No.2016YFC1400200 and 2016YFC1400204National Natural Science Foundation of China under Grants No.41476026,41676024 and 41376040Fundamental Research Funds for the Central Universities of China under Grant No.220720140506
文摘This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node individually employing traditional automatic-repeat-request(ARQ) protocol.We propose a practical node cooperation(NC) protocol to enhance the collection efficiency,utilizing the fact that underwater nodes can overhear the transmission of others.To reduce the source level of underwater nodes,the underwater data collection area is divided into several sub-zones,and in each sub-zone,the mobile surface node adopting the NC protocol could switch adaptively between selective relay cooperation(SRC) and dynamic network coded cooperation(DNC) .The difference of SRC and DNC lies in whether or not the selected relay node combines the local data and the data overheard from undecoded node(s) to form network coded packets in the retransmission phase.The NC protocol could also be applied across the sub-zones due to the wiretap property.In addition,we investigate the effects of different mobile collection paths,collection area division and cooperative zone design for energy saving.The numerical results showthat the proposed NC protocol can effectively save energy compared with the traditional ARQ scheme.
文摘Minerals and resources trade and investment play a pivotal role in economic and trade relations between China and Australia.In recent years,although China-Australia political relations have been at a low point,China?Australia minerals and energy cooperation has exhibited a different trend to that of political relations,and also from the engagement during previous periods.Minerals and energy trade has increased steadily,while investment is becoming more difficult,particularly for large projects.There has been a clear green transition in trade and investment in this functional area,and uncertainty has increased due to the influence of factors such as the Belt and Road Initiative(BRI),the shale gas revolution and China-US trade disputes.Because this is one of the pillars for economic growth for both countries,and for their trade and investment ties,and because of the importance of low-carbon transition,the free trade system,and global and regional governance,minerals and energy cooperation can serve as a platform for improving and promoting bilateral relations.It has been suggested that China should seize the opportunity to improve bilateral relations by deepening two-way investment,joining hands with Australia on developing more products in more areas,and with new cooperation models.This research will be significant for understanding the status quo of China-Australia cooperation in minerals and energy,and for improving bilateral relations,and even international energy governance.
基金support from the National Natural Science Foundation of China(Grant No.71531003)Philosophy and Social Science Research Fund of Chengdu University of Technology(YJ2021-QN005)Center for Trans-Himalaya Studies(KX2022B01)。
文摘This paper explores the incentives of investment in renewable energy of two utility firms who compete or cooperate under either a cap-and-trade grandfathering mechanism(GM)or benchmarking mechanism(BM).We find that utility firms will invest in renewable energy more under BM than under GM,in both competitive and cooperative markets,and they will invest more in a competitive market than in a cooperative market,under either GM or BM.Furthermore,utility firms will produce more electricity and generate more total carbon emissions under BM than under GM.The profits of two firms,however,are higher in cooperative market than in competitive market.The government will benefit from implementing a BM to encourage utility firms to invest in renewable energy in a competing market.
文摘The "Belt and Road Initiative"was proposed by China in order to deepen international cooperation. The promotion of this initiative will have a positive and far-reaching impact on the sustainable development of China's economy.Energy cooperation has become an important part of China's opening up to the outside world. It is of great sign^cance in safeguarding national security,ensuring stable supply of energy,improving China's rights of speech in international energy markets,and helping China's energy companies to "go global".So far, energy cooperation along the Belt and Road has achieved a good start.Oil and gas companies such as CNPC and Sinopec have moved very fast in overseas cooperation,and new energy companies are actively following up.In order to achieve practical results in China's energy cooperation,this paper analyzesseveral problems and puts forward policy proposals.
文摘Energy trade is the barometer of global trade in goods and plays an integral role international trade. As an important part of the implementation of the Belt and Road Initiative,multilateral partnership in energy trade is one of the most cooperative and promising areas for the countries along the Belt and Road.Since the implementation of the initiative five years ago,cooperation in energy trade between China and the countries along the Belt and Road has been deepening.This development not only benefits the energy producers,energy consumers and energy corridors,but it also elevates China's influence and leadership in the regional energy market, contributing to the construction of a new international energy order.
文摘Energy trade is the barometer of global trade in goods and plays an integral role international trade. As an important part of the implementation of the "Belt and Road"Initiative,multilateral partnership in energy trade is one of the most cooperative and promising areas for the countries along the "Belt and Road".Since the implementation of the initiative five years ago,cooperation in energy trade between China and the countries along the "Belt and Road"has been deepening.This development not only benefits the energy producers,energy consumers and energy corridors,but it also elevates China's influence and leadership in the regional energy market,contributing to the construction of a new international energy order.
文摘The economic rise of the BRICS countries(Brazil, Russia, India, China and South Africa) is closely tied to global energy politics and their increased consumption of global energy. Energy cooperation is one of the main forces behind the development of BRICS. Looking forward, energy concerns will undoubtedly remain an important influencing force for the BRICS, shaping their domestic politics and international relations. The pursuit of oil and gas(China, India, and South Africa) to support economic development and the search for stable petroleum markets(Brazil and Russia) have shaped BRICS relations with other countries and regions. This article is trying to elaborate on the reasons why BRICS Energy cooperation is beneficial for its members; also, this article regards the main challenges hindering cooperation, analyzes BRICS energy cooperation through the use of SWOT analysis and muses potential strategic points for BRICS countries up until 2050.
文摘Over the past two decades, as the main battlefield of China's international energy cooperation, countries along the Belt and Road have had good foundations in the foreign investment. Through China's efforts to build the Belt and Road, energy cooperation has enjoyed first-mover advantages. Looking ahead, the countries along the Belt and Road are predicted to enjoy a promising future in energy cooperation because of their abundant energy resources, their role as complements to China's economic development, and their vast amounts of cooperation potential. At the same time, we are also keenly aware that there are a number of risks caused by geopolitics, policy changes, price fluctuations and legal compliance in energy cooperation among the countries along the Belt and Road. Moreover, it is urgent for Chinese enterprises to enhance their international capabilities. In this context, it is necessary to further maintain and make full use of their first-mover advantages and play a guiding and demonstrating role. Enterprises should actively adapt to new changes, while the government should make progress in policy coordination, facility connectivity, unimpeded trade, financed integration and people-to-people bonds, so as to keep deepening international energy cooperation and to build an energy silk road and a community with a shared future for energy.