Urban large-scale topographical maps can be renewed by means of overlapping the original digital line graph (DLG) and up-to-date remote sensitive images which have high precision and have been orthographically rectifi...Urban large-scale topographical maps can be renewed by means of overlapping the original digital line graph (DLG) and up-to-date remote sensitive images which have high precision and have been orthographically rectified precisely. Quick Bird panchromatic remote sensing image is used and an urban area with even terrain and dense buildings is selected as experimental area. Ground control points (GCPs) are selected on a new 1∶500 topographical map and multinomial model is applied for rectification. After rectification the absolute positional error of a single point of the image is less than 1m, therefore this method is suitable for renewing topographical maps of up to (1∶2 000) scale.展开更多
Renewing warranty can provide customers with better service,and thus help manufacturers to gain market opportunities.In engineering practice,the cost for replacement is usually higher than the cost for maintenance,hen...Renewing warranty can provide customers with better service,and thus help manufacturers to gain market opportunities.In engineering practice,the cost for replacement is usually higher than the cost for maintenance,hence manufacturers often face huge challenge to reduce the warranty service cost.With consideration of the warranty deadline,we propose a two-stage optimization model for renewing warranty.In the first stage,a renewing warranty with deadline(RWD)policy is implemented,where the deadline represents the cumulative uptime threshold.When the cumulative uptime exceeds the deadline,the product will be minimally repaired and kept to the residual warranty period.When RWD is expired,the replacement warranty with limited repairs(RWLR)policy is applied.Under the free replacement and pro-rata warranty policy,the corresponding two-stage cost optimization model is established from the manufacturer’s perspective,the aim is to minimize the cost rate and obtain the optimal warranty period.A numerical example is provided to illustrate the validity of the proposed model,and the sensitivity analysis is also carried out.展开更多
In the one-dimensional renewing warranty period,the quality of the spares for product is likely to be improved during the warranty period.Therefore,upgrading maintenance becomes more and more common.Then the manufactu...In the one-dimensional renewing warranty period,the quality of the spares for product is likely to be improved during the warranty period.Therefore,upgrading maintenance becomes more and more common.Then the manufacturers(customers) may have to decide whether or not to provide(buy) the warranty considering upgrading maintenance.This paper presents a mathematical model considering upgrading maintenance for products with multiple failure modes.Upgrading maintenance is taken into account with the assumption that the warranted item is upgraded one time during the warranty cycle.The upgrading maintenance is carried out,when the corrective maintenance is taken place.After upgrading maintenance,the high-quality spares are used to replace the failed item.In the numerical example,the results of the models are calculated.Monte Carlo simulation results are compared with the analytical results to demonstrate the correctness and efficiency of the proposed models considering upgrading maintenance.展开更多
To create a scientific way to renew the grades of cultivated land at county level, monitoring points were set up according to the monitoring control regions and grade types of cultivated land in Daxing District, Beiji...To create a scientific way to renew the grades of cultivated land at county level, monitoring points were set up according to the monitoring control regions and grade types of cultivated land in Daxing District, Beijing, and soil samples were collected to carry out chemical analysis. Afterwards, the input and output data of cultivated land in each village were surveyed to renew the grades of cultivated land. The results indicate that the average natural grade of cultivated land was 8.4, which was equal to that of 2004; the average utilization grade was 8.1, which was slightly higher than that of 2004; the average economic grade was 9.9, which was lower than that of 2004. It is concluded that it is scientific to renew cultivated land grades through scientifically setting monitoring points according to the monitoring control regions and grade types of cultivated land.展开更多
Distinguished Vice-Minister Li Jinjun,Ladies and gentlemen,friends,It is a delightful event for all of us to renew the MOU between FES and CAFIU for the nineth time.Years of cooperation and fruitful results are worth ...Distinguished Vice-Minister Li Jinjun,Ladies and gentlemen,friends,It is a delightful event for all of us to renew the MOU between FES and CAFIU for the nineth time.Years of cooperation and fruitful results are worth celebrating.For a long period of time,the two organizations have been making efforts to put the thoughts of Deng Xiaopeng and Willy Brandt into practice,namely,the thoughts of having dialogue and enhancing mutual understanding while展开更多
Respected President Beck,Respected vips,Ladies,gentlemen,friends,I am delighted to sign the Memorandum of Understanding on Cooperation between CAFIU and FES with President Beck here today.This is an important moment...Respected President Beck,Respected vips,Ladies,gentlemen,friends,I am delighted to sign the Memorandum of Understanding on Cooperation between CAFIU and FES with President Beck here today.This is an important moment in the history of the relations between CAFIU and FES,which signifies that the sound cooperation between both sides will展开更多
美国作曲家玛丽莲·丝露德(Marilyn Shrude)是著名的钢琴家和作曲家,她所作的《重新开始的神话》(Renewing the Myth)是当代萨克斯管经典音乐作品之一,也是萨克斯管最著名的比赛——第三届阿道夫萨克斯管比赛的必奏曲目.我们通过对...美国作曲家玛丽莲·丝露德(Marilyn Shrude)是著名的钢琴家和作曲家,她所作的《重新开始的神话》(Renewing the Myth)是当代萨克斯管经典音乐作品之一,也是萨克斯管最著名的比赛——第三届阿道夫萨克斯管比赛的必奏曲目.我们通过对这首作品的分析可以了解萨克斯管当代音乐的曲式和技巧.展开更多
The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3...The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells. The stem cells give rise to three main progenitors: prepit, preneck and preparietal cells. Parietal cells develop either directly from the noncycling preparietal cells or less commonly via differentiation of the cycling prepit and preneck cell progenitors. The formation of a parietal cell is a sequential process which involves diminishment of glycocalyx, production of cytoplasmic tubulovesicles, an increase in number and length of microvilli, an increase in number and size of mitochondria, and fi nally, expansion and invagination of the apical membrane with the formation of an intracellular canalicular system. Little is known about the genetic counterparts of these morphological events. However, the time dimension of parietal cell production and the consequences of its alteration on the biological features of the gastric gland are well documented. The production of a new parietal cell takes about 2 d. However, mature parietal cells have a long lifespan during which they migrate bidirectionally while their functional activity for acid secretion gradually diminishes. Following an average lifespan of about 54 d, in mice, old parietal cells undergo degeneration and elimination. Various approaches for genetic alteration of the development of parietal cells have provided evidence in support of their role as governors of the stem/progenitor cell proliferation and differentiation programs. Revealing the dynamic features and the various roles of parietal cells would help in a better understanding of the biological features of the gastric glands and would hopefully help in providing a basis for the development of new strategies for prevention, early detection and/or therapy of various gastric disorders in which parietal cells are involved, such as atrophic gastritis, peptic ulcer disease and gastric cancer.展开更多
The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack o...The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack of sanitation facilities.The project,targeting 14,082 households,started last year.展开更多
In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-qualit...In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-quality urban development and continuously meet people’s growing aspirations for a better life.Wuhu,in central China’s Anhui Province,has consistently enhanced its urban functions and services to build a modern,people-oriented city that is innovative,livable,beautiful,resilient,and smart.展开更多
The Chinese vice president’s visit to five countries bolsters traditionalfriendships and strengthens multi-level cooperation Chinese Vice President Xi Jinpingdebuted in his first performance onthe international stage...The Chinese vice president’s visit to five countries bolsters traditionalfriendships and strengthens multi-level cooperation Chinese Vice President Xi Jinpingdebuted in his first performance onthe international stage with a tourof five countries in Asia. On June17-25, he paid state visits to North Korea,Mongolia, Saudi Arabia, Qatar and Yemen.展开更多
China and the EU revitalize business ties while seeking to address concerns Chinese State Councilor Dai Bingguoand Catherine Ashton,Vice President of the European Counciland EU High Representative for Foreign Affairs ...China and the EU revitalize business ties while seeking to address concerns Chinese State Councilor Dai Bingguoand Catherine Ashton,Vice President of the European Counciland EU High Representative for Foreign Affairs and Security Policy,co-chaired the first upgraded China-EU strategic dialogue in Guiyang,capital of southwest China’s Guizhou Province, on September 1.展开更多
History was made when Chinese Premier Wen Jiabao kicked off his seven-nation Africa tour in June in Cairo, attending a gala at the foot of the Pyramids of Giza to mark 50 years of China-Egypt diplomatic relations in t...History was made when Chinese Premier Wen Jiabao kicked off his seven-nation Africa tour in June in Cairo, attending a gala at the foot of the Pyramids of Giza to mark 50 years of China-Egypt diplomatic relations in the company of his Egyptian counterpart Ahmed Nazef. This is the first time the world heritage site has ever been used for such an occasion. Following on the heels of the two ancient civilizations consolidating their relationship, Egyptian Ambassador to China Mahmoud Allam shared his visions on ...展开更多
The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable energy.Solar ener...The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable energy.Solar energy,among the various renewable sources,is particularly appealing due to its abundant availability.However,the efficiency of commercial solar photovoltaic(PV)modules is hindered by several factors,notably their conversion efficiency,which averages around 19%.This efficiency can further decline to 10%–16%due to temperature increases during peak sunlight hours.This study investigates the cooling of PV modules by applying water to their front surface through Computational fluid dynamics(CFD).The study aimed to determine the optimal conditions for cooling the PV module by analyzing the interplay between water film thickness,Reynolds number,and their effects on temperature reduction and heat transfer.The CFD analysis revealed that the most effective cooling condition occurred with a 5 mm thick water film and a Reynolds number of 10.These specific parameters were found to maximize the heat transfer and temperature reduction efficiency.This finding is crucial for the development of practical and efficient cooling systems for PV modules,potentially leading to improved performance and longevity of solar panels.Alternative cooling fluids or advanced cooling techniques that might offer even better efficiency or practical benefits.展开更多
Improving the quality of life for Earth's growing population is a complex task that requires the development of new technologies and materials. Perhaps the biggest challenge is access to clean and renewable energy...Improving the quality of life for Earth's growing population is a complex task that requires the development of new technologies and materials. Perhaps the biggest challenge is access to clean and renewable energy sources that can drive a sustainable future. Photovoltaics, today mainly represented by silicon-based solar cells, convert solar energy into electricity and is already an important component in the renewable energy portfolio.展开更多
The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,dist...The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,distributed renewable resources,and data-driven intelligence,have emerged as the backbone of this evolution.This convergence,however,introduces unprecedented complexities in resilience,security,stability,and market operation.This special issue presents five pivotal studies addressing these interconnected challenges,offering novel methodologies and insights to advance the efficiency,resilience,and sustainability of modern power systems.展开更多
The rapid development of energy storage technology has provided tremendous support for the energy transition in countries worldwide.Salt cavern energy storage,as a form of energy storage technology,has gained widespre...The rapid development of energy storage technology has provided tremendous support for the energy transition in countries worldwide.Salt cavern energy storage,as a form of energy storage technology,has gained widespread attention due to its large storage capacity and broad distribution.Therefore,this paper primarily discusses the current research status of salt cavern energy storage technology,with a focus on analyzing its classifications,advantages,disadvantages,and the challenges and countermeasures associated with its development.This study aims to promote further advancement in salt cavern energy storage technology.展开更多
Recently,one of the main challenges facing the smart grid is insufficient computing resources and intermittent energy supply for various distributed components(such as monitoring systems for renewable energy power sta...Recently,one of the main challenges facing the smart grid is insufficient computing resources and intermittent energy supply for various distributed components(such as monitoring systems for renewable energy power stations).To solve the problem,we propose an energy harvesting based task scheduling and resource management framework to provide robust and low-cost edge computing services for smart grid.First,we formulate an energy consumption minimization problem with regard to task offloading,time switching,and resource allocation for mobile devices,which can be decoupled and transformed into a typical knapsack problem.Then,solutions are derived by two different algorithms.Furthermore,we deploy renewable energy and energy storage units at edge servers to tackle intermittency and instability problems.Finally,we design an energy management algorithm based on sampling average approximation for edge computing servers to derive the optimal charging/discharging strategies,number of energy storage units,and renewable energy utilization.The simulation results show the efficiency and superiority of our proposed framework.展开更多
With the increasing integration of large-scale distributed energy resources into the grid,traditional distribution network optimization and dispatch methods struggle to address the challenges posed by both generation ...With the increasing integration of large-scale distributed energy resources into the grid,traditional distribution network optimization and dispatch methods struggle to address the challenges posed by both generation and load.Accounting for these issues,this paper proposes a multi-timescale coordinated optimization dispatch method for distribution networks.First,the probability box theory was employed to determine the uncertainty intervals of generation and load forecasts,based on which,the requirements for flexibility dispatch and capacity constraints of the grid were calculated and analyzed.Subsequently,a multi-timescale optimization framework was constructed,incorporating the generation and load forecast uncertainties.This framework included optimization models for dayahead scheduling,intra-day optimization,and real-time adjustments,aiming to meet flexibility needs across different timescales and improve the economic efficiency of the grid.Furthermore,an improved soft actor-critic algorithm was introduced to enhance the uncertainty exploration capability.Utilizing a centralized training and decentralized execution framework,a multi-agent SAC network model was developed to improve the decision-making efficiency of the agents.Finally,the effectiveness and superiority of the proposed method were validated using a modified IEEE-33 bus test system.展开更多
Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell ...Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell industry has experienced unprecedented development. The full utilization of solar energy resources remains an urgent issue to be addressed.展开更多
文摘Urban large-scale topographical maps can be renewed by means of overlapping the original digital line graph (DLG) and up-to-date remote sensitive images which have high precision and have been orthographically rectified precisely. Quick Bird panchromatic remote sensing image is used and an urban area with even terrain and dense buildings is selected as experimental area. Ground control points (GCPs) are selected on a new 1∶500 topographical map and multinomial model is applied for rectification. After rectification the absolute positional error of a single point of the image is less than 1m, therefore this method is suitable for renewing topographical maps of up to (1∶2 000) scale.
基金Project(71671035) supported by the National Natural Science Foundation of China
文摘Renewing warranty can provide customers with better service,and thus help manufacturers to gain market opportunities.In engineering practice,the cost for replacement is usually higher than the cost for maintenance,hence manufacturers often face huge challenge to reduce the warranty service cost.With consideration of the warranty deadline,we propose a two-stage optimization model for renewing warranty.In the first stage,a renewing warranty with deadline(RWD)policy is implemented,where the deadline represents the cumulative uptime threshold.When the cumulative uptime exceeds the deadline,the product will be minimally repaired and kept to the residual warranty period.When RWD is expired,the replacement warranty with limited repairs(RWLR)policy is applied.Under the free replacement and pro-rata warranty policy,the corresponding two-stage cost optimization model is established from the manufacturer’s perspective,the aim is to minimize the cost rate and obtain the optimal warranty period.A numerical example is provided to illustrate the validity of the proposed model,and the sensitivity analysis is also carried out.
基金the National Society Science Foundation of China(No.14GJ003-135)the National Natural Science Foundation of China(No.71401173)
文摘In the one-dimensional renewing warranty period,the quality of the spares for product is likely to be improved during the warranty period.Therefore,upgrading maintenance becomes more and more common.Then the manufacturers(customers) may have to decide whether or not to provide(buy) the warranty considering upgrading maintenance.This paper presents a mathematical model considering upgrading maintenance for products with multiple failure modes.Upgrading maintenance is taken into account with the assumption that the warranted item is upgraded one time during the warranty cycle.The upgrading maintenance is carried out,when the corrective maintenance is taken place.After upgrading maintenance,the high-quality spares are used to replace the failed item.In the numerical example,the results of the models are calculated.Monte Carlo simulation results are compared with the analytical results to demonstrate the correctness and efficiency of the proposed models considering upgrading maintenance.
基金Supported by the Scientific Research Project of Ministry of Land and Resources of the People's Public of China in Public Welfare Industries(201011006)
文摘To create a scientific way to renew the grades of cultivated land at county level, monitoring points were set up according to the monitoring control regions and grade types of cultivated land in Daxing District, Beijing, and soil samples were collected to carry out chemical analysis. Afterwards, the input and output data of cultivated land in each village were surveyed to renew the grades of cultivated land. The results indicate that the average natural grade of cultivated land was 8.4, which was equal to that of 2004; the average utilization grade was 8.1, which was slightly higher than that of 2004; the average economic grade was 9.9, which was lower than that of 2004. It is concluded that it is scientific to renew cultivated land grades through scientifically setting monitoring points according to the monitoring control regions and grade types of cultivated land.
文摘Distinguished Vice-Minister Li Jinjun,Ladies and gentlemen,friends,It is a delightful event for all of us to renew the MOU between FES and CAFIU for the nineth time.Years of cooperation and fruitful results are worth celebrating.For a long period of time,the two organizations have been making efforts to put the thoughts of Deng Xiaopeng and Willy Brandt into practice,namely,the thoughts of having dialogue and enhancing mutual understanding while
文摘Respected President Beck,Respected vips,Ladies,gentlemen,friends,I am delighted to sign the Memorandum of Understanding on Cooperation between CAFIU and FES with President Beck here today.This is an important moment in the history of the relations between CAFIU and FES,which signifies that the sound cooperation between both sides will
文摘美国作曲家玛丽莲·丝露德(Marilyn Shrude)是著名的钢琴家和作曲家,她所作的《重新开始的神话》(Renewing the Myth)是当代萨克斯管经典音乐作品之一,也是萨克斯管最著名的比赛——第三届阿道夫萨克斯管比赛的必奏曲目.我们通过对这首作品的分析可以了解萨克斯管当代音乐的曲式和技巧.
基金Supported by Terry Fox Fund for Cancer Research and UAE University
文摘The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells. The stem cells give rise to three main progenitors: prepit, preneck and preparietal cells. Parietal cells develop either directly from the noncycling preparietal cells or less commonly via differentiation of the cycling prepit and preneck cell progenitors. The formation of a parietal cell is a sequential process which involves diminishment of glycocalyx, production of cytoplasmic tubulovesicles, an increase in number and length of microvilli, an increase in number and size of mitochondria, and fi nally, expansion and invagination of the apical membrane with the formation of an intracellular canalicular system. Little is known about the genetic counterparts of these morphological events. However, the time dimension of parietal cell production and the consequences of its alteration on the biological features of the gastric gland are well documented. The production of a new parietal cell takes about 2 d. However, mature parietal cells have a long lifespan during which they migrate bidirectionally while their functional activity for acid secretion gradually diminishes. Following an average lifespan of about 54 d, in mice, old parietal cells undergo degeneration and elimination. Various approaches for genetic alteration of the development of parietal cells have provided evidence in support of their role as governors of the stem/progenitor cell proliferation and differentiation programs. Revealing the dynamic features and the various roles of parietal cells would help in a better understanding of the biological features of the gastric glands and would hopefully help in providing a basis for the development of new strategies for prevention, early detection and/or therapy of various gastric disorders in which parietal cells are involved, such as atrophic gastritis, peptic ulcer disease and gastric cancer.
文摘The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack of sanitation facilities.The project,targeting 14,082 households,started last year.
文摘In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-quality urban development and continuously meet people’s growing aspirations for a better life.Wuhu,in central China’s Anhui Province,has consistently enhanced its urban functions and services to build a modern,people-oriented city that is innovative,livable,beautiful,resilient,and smart.
文摘The Chinese vice president’s visit to five countries bolsters traditionalfriendships and strengthens multi-level cooperation Chinese Vice President Xi Jinpingdebuted in his first performance onthe international stage with a tourof five countries in Asia. On June17-25, he paid state visits to North Korea,Mongolia, Saudi Arabia, Qatar and Yemen.
文摘China and the EU revitalize business ties while seeking to address concerns Chinese State Councilor Dai Bingguoand Catherine Ashton,Vice President of the European Counciland EU High Representative for Foreign Affairs and Security Policy,co-chaired the first upgraded China-EU strategic dialogue in Guiyang,capital of southwest China’s Guizhou Province, on September 1.
文摘History was made when Chinese Premier Wen Jiabao kicked off his seven-nation Africa tour in June in Cairo, attending a gala at the foot of the Pyramids of Giza to mark 50 years of China-Egypt diplomatic relations in the company of his Egyptian counterpart Ahmed Nazef. This is the first time the world heritage site has ever been used for such an occasion. Following on the heels of the two ancient civilizations consolidating their relationship, Egyptian Ambassador to China Mahmoud Allam shared his visions on ...
文摘The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable energy.Solar energy,among the various renewable sources,is particularly appealing due to its abundant availability.However,the efficiency of commercial solar photovoltaic(PV)modules is hindered by several factors,notably their conversion efficiency,which averages around 19%.This efficiency can further decline to 10%–16%due to temperature increases during peak sunlight hours.This study investigates the cooling of PV modules by applying water to their front surface through Computational fluid dynamics(CFD).The study aimed to determine the optimal conditions for cooling the PV module by analyzing the interplay between water film thickness,Reynolds number,and their effects on temperature reduction and heat transfer.The CFD analysis revealed that the most effective cooling condition occurred with a 5 mm thick water film and a Reynolds number of 10.These specific parameters were found to maximize the heat transfer and temperature reduction efficiency.This finding is crucial for the development of practical and efficient cooling systems for PV modules,potentially leading to improved performance and longevity of solar panels.Alternative cooling fluids or advanced cooling techniques that might offer even better efficiency or practical benefits.
基金financially supported by the National Science Foundation of China grant (62322407, 22279034, 52261145698, W2421103)Shanghai Science and Technology Innovation Action Plan (22ZR1418900, 24110714100)+1 种基金the Swedish Research Council (project grant no. 2020-04538)the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Link?ping University (Faculty Grant SFO Mat LiU no. 2009 00971)。
文摘Improving the quality of life for Earth's growing population is a complex task that requires the development of new technologies and materials. Perhaps the biggest challenge is access to clean and renewable energy sources that can drive a sustainable future. Photovoltaics, today mainly represented by silicon-based solar cells, convert solar energy into electricity and is already an important component in the renewable energy portfolio.
文摘The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,distributed renewable resources,and data-driven intelligence,have emerged as the backbone of this evolution.This convergence,however,introduces unprecedented complexities in resilience,security,stability,and market operation.This special issue presents five pivotal studies addressing these interconnected challenges,offering novel methodologies and insights to advance the efficiency,resilience,and sustainability of modern power systems.
基金supported by the National Natural Science Foundation of China(Grant No.U20A20266)Scientific and technological research projects in Sichuan province(Grant No.2024NSFSC0973)Sichuan Science and Technology Program(2024YFHZ0286)。
文摘The rapid development of energy storage technology has provided tremendous support for the energy transition in countries worldwide.Salt cavern energy storage,as a form of energy storage technology,has gained widespread attention due to its large storage capacity and broad distribution.Therefore,this paper primarily discusses the current research status of salt cavern energy storage technology,with a focus on analyzing its classifications,advantages,disadvantages,and the challenges and countermeasures associated with its development.This study aims to promote further advancement in salt cavern energy storage technology.
基金supported in part by the National Natural Science Foundation of China under Grant No.61473066in part by the Natural Science Foundation of Hebei Province under Grant No.F2021501020+2 种基金in part by the S&T Program of Qinhuangdao under Grant No.202401A195in part by the Science Research Project of Hebei Education Department under Grant No.QN2025008in part by the Innovation Capability Improvement Plan Project of Hebei Province under Grant No.22567637H
文摘Recently,one of the main challenges facing the smart grid is insufficient computing resources and intermittent energy supply for various distributed components(such as monitoring systems for renewable energy power stations).To solve the problem,we propose an energy harvesting based task scheduling and resource management framework to provide robust and low-cost edge computing services for smart grid.First,we formulate an energy consumption minimization problem with regard to task offloading,time switching,and resource allocation for mobile devices,which can be decoupled and transformed into a typical knapsack problem.Then,solutions are derived by two different algorithms.Furthermore,we deploy renewable energy and energy storage units at edge servers to tackle intermittency and instability problems.Finally,we design an energy management algorithm based on sampling average approximation for edge computing servers to derive the optimal charging/discharging strategies,number of energy storage units,and renewable energy utilization.The simulation results show the efficiency and superiority of our proposed framework.
基金funded by Jilin Province Science and Technology Development Plan Project,grant number 20220203163SF.
文摘With the increasing integration of large-scale distributed energy resources into the grid,traditional distribution network optimization and dispatch methods struggle to address the challenges posed by both generation and load.Accounting for these issues,this paper proposes a multi-timescale coordinated optimization dispatch method for distribution networks.First,the probability box theory was employed to determine the uncertainty intervals of generation and load forecasts,based on which,the requirements for flexibility dispatch and capacity constraints of the grid were calculated and analyzed.Subsequently,a multi-timescale optimization framework was constructed,incorporating the generation and load forecast uncertainties.This framework included optimization models for dayahead scheduling,intra-day optimization,and real-time adjustments,aiming to meet flexibility needs across different timescales and improve the economic efficiency of the grid.Furthermore,an improved soft actor-critic algorithm was introduced to enhance the uncertainty exploration capability.Utilizing a centralized training and decentralized execution framework,a multi-agent SAC network model was developed to improve the decision-making efficiency of the agents.Finally,the effectiveness and superiority of the proposed method were validated using a modified IEEE-33 bus test system.
文摘Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell industry has experienced unprecedented development. The full utilization of solar energy resources remains an urgent issue to be addressed.
