Purpose-This study aims to research the large cross-section tunnel stability evaluation method corrected after considering the thickness-span ratio.Design/methodology/approach-First,taking the Liuyuan Tunnel of Huangg...Purpose-This study aims to research the large cross-section tunnel stability evaluation method corrected after considering the thickness-span ratio.Design/methodology/approach-First,taking the Liuyuan Tunnel of Huanggang-Huangmei High-Speed Railway as an example and taking deflection of the third principal stress of the surrounding rock at a vault after tunnel excavation as the criterion,the critical buried depth of the large section tunnel was determined.Then,the strength reduction method was employed to calculate the tunnel safety factor under different rock classes and thickness-span ratios,and mathematical statistics was conducted to identify the relationships of the tunnel safety factor with the thickness-span ratio and the basic quality(BQ)index of the rock for different rock classes.Finally,the influences of thickness-span ratio,groundwater,initial stress of rock and structural attitude factors were considered to obtain the corrected BQ,based on which the stability of a large cross-section tunnel with a depth of more than 100 m during mechanized operation was analyzed.This evaluation method was then applied to Liuyuan Tunnel and Cimushan No.2 Tunnel of Chongqing Urban Expressway for verification.Findings-This study shows that under different rock classes,the tunnel safety factor is a strict power function of the thickness-span ratio,while a linear function of the BQ to some extent.It is more suitable to use the corrected BQ as a quantitative index to evaluate tunnel stability according to the actual conditions of the site.Originality/value-The existing industry standards do not consider the influence of buried depth and span in the evaluation of tunnel stability.The stability evaluation method of large section tunnel considering the correction of overburden span ratio proposed in this paper achieves higher accuracy for the stability evaluation of surrounding rock in a full or large-section mechanized excavation of double line high-speed railway tunnels.展开更多
Exploring the inner law of the economic operation of urbanization can understand the regulation mechanism of the optimal distribution of urban resource allocation. In this regard, we propose to explore and analyze the...Exploring the inner law of the economic operation of urbanization can understand the regulation mechanism of the optimal distribution of urban resource allocation. In this regard, we propose to explore and analyze the inner law of urbanization economic operation and its application. The study found that the urbanization economy originated from the urban agglomeration effect, which includes the agglomeration economic operation mechanism and spillover effect operation mechanism, based on which three kinds of inner laws of urbanization economic operation are explored, combined with the economic operation law, the non-equilibrium state of the declining cities are regulated and applied, and the results show that the analysis of the inner laws of urbanization economic operation has a direct significance in guiding the real economic process.展开更多
With the rapid development of the market economy, complex changes have occurred in the market environment, and the competition among enterprises has become extremely fierce. The transformation of the structure of the ...With the rapid development of the market economy, complex changes have occurred in the market environment, and the competition among enterprises has become extremely fierce. The transformation of the structure of the market economy has prompted enterprises to seek for new developments and innovations. Under the background of the new economy, enterprises must begin from the perspective of internal management and internal strategic development to ensure quality enterprise operation mechanism innovation. This would help direct enterprise operation and development as well as demonstrate the value of enterprise internal management. In this way, enterprises will be able to array their overall competitiveness. This paper comprises a detailed analysis of the connotation and innovation of enterprise operation mechanism under the economic transformation, with the purpose of investigating the innovation strategy of enterprise operation mechanism under the economic transformation.展开更多
Based on the theory of ecological organization,this paper analyzes the operation mechanism of chemical industry park(CIP)ecosystem by means of dynamic simulation.The research shows that the CIP ecosystem is a complex ...Based on the theory of ecological organization,this paper analyzes the operation mechanism of chemical industry park(CIP)ecosystem by means of dynamic simulation.The research shows that the CIP ecosystem is a complex ecological system whose operation mechanism includes two levels,namely individual enterprises and ecosystem.At the level of individual enterprise,there are competition,symbiosis,invasion and other interactions between enterprises in the CIP ecosystem.Through the pre-determined judgment of the competition effect coefficient and the symbiosis effect coefficient,we calculate how the enterprises influence each other,and then generate their respective operation paths,andfinally realize the long-term balance of the system.At the level of ecosystem,the CIP ecosystem makes self-organizing and self-adaptive adjustments and changes due to the changes of the exter-nal environment in policy,manpower,technology,capital,market,etc.,thus reaching the equilibrium state of coordinated operation and stable symbiosis with the external environment.展开更多
Stable operating region in the HL-1M tokamak has been extended by means of wall conditioning, core fuelling and current control techniques. The mechanisms of the extension are analyzed in this paper. Lithiumization di...Stable operating region in the HL-1M tokamak has been extended by means of wall conditioning, core fuelling and current control techniques. The mechanisms of the extension are analyzed in this paper. Lithiumization diminishes the impurities and hydrogen recycling to the lowest level. After lithiumization a high density up to 7×1019 m-3 was obtained easily by strong gas puffing with ordinary ohmic discharge alone. More attractively we found that metal Li-coating exhibited the effects of wall stabilization. The low qα limit with higher density was extended by a factor of 1.5-2 in comparison with that for boronization, and 1.2 for siliconization. Siliconization not only extended stable operating region significantly by itself, but also provided a good target plasma for other experiments of raising density limit. Core fuelling schemes are favourable especially for siliconized wall with a higher level of medium-Z impurity (Z = 14). After siliconization the maximum density near to 1020 m-3 was achieved by a combination of supersonic molecule beam injection and multipellet injection. The new defined slope of Hugill limit illustrating more clearly the situation under low qα and high ne discharges was created to indicate the new region extended by combining IP ramp-up with core fuelling. The slope with a large Murakami coefficient increased by a factor of 50-60 %.展开更多
This paper studies the operation mechanism of crowdfunding for rural tourism from three aspects:the main body of crowdfunding for rural tourism,driving factors and operating stage.At the same time,this paper analyzes ...This paper studies the operation mechanism of crowdfunding for rural tourism from three aspects:the main body of crowdfunding for rural tourism,driving factors and operating stage.At the same time,this paper analyzes the operation risk of crowdfunding for rural tourism from five aspects:legal risk,information asymmetry risk,capital security risk,interest subject conflict risk and industry development risk.It also puts forward measures and suggestions on the promotion of crowdfunding for rural tourism from four aspects:improving market awareness,providing professional services,issuing relevant laws and regulations and regulating the development of the industry.展开更多
The China National Textiles I/E Corp (Chinatex), one of the foreign trade companies in the country with the biggest import and export value, exported more textiles and expanded its business at home and abroad in 1994,...The China National Textiles I/E Corp (Chinatex), one of the foreign trade companies in the country with the biggest import and export value, exported more textiles and expanded its business at home and abroad in 1994, in spite of the shortage of raw materials and the rise in prices. Chinatex’s import and export value totalled US$2.718 billion last year, a rise of 43.9% over the previous year. The quality of the exports also improved. The company’s Beijing branch exported US$370 million worth of goods, 33.3% more than in the previous year. Its enterprises abroad had a turnover of US$1 billion in 1994.展开更多
According to customs statistics, China’s exports of machinery and electric products in 1996 were worth US$ 48.21 billion, an increase of 9.9 percent over the preceding year, and 8.4 percent higher than the growth rat...According to customs statistics, China’s exports of machinery and electric products in 1996 were worth US$ 48.21 billion, an increase of 9.9 percent over the preceding year, and 8.4 percent higher than the growth rate of the nation’s total exports. The proportion of machinery and electric product exports in the nation’s total foreign trade volume\ increased from 29.5 percent in 1995 to 31.9 percent in 1996, a growth at 2.4 percent.展开更多
In terms of the coherent state evolution in phase space,we present a quantum mechanical version of the classical Liouville theorem.The evolution of the coherent state from |z〉to|sz-rz*〉 corresponds to the motion ...In terms of the coherent state evolution in phase space,we present a quantum mechanical version of the classical Liouville theorem.The evolution of the coherent state from |z〉to|sz-rz*〉 corresponds to the motion from a point z(q,p) to another point sz-rz* with |s|2-|r|2=1.The evolution is governed by the so-called Fresnel operator U(s,r) that was recently proposed in quantum optics theory,which classically corresponds to the matrix optics law and the optical Fresnel transformation,and obeys group product rules.In other words,we can recapitulate the Liouville theorem in the context of quantum mechanics by virtue of coherent state evolution in phase space,which seems to be a combination of quantum statistics and quantum optics.展开更多
Blasted(1995)is knitted by Sarah Kane as a huge and intricate net of power,among whose threads every character gets entangled.By deconstructing the configuration of power from two dimensions:body shame,the seen body,w...Blasted(1995)is knitted by Sarah Kane as a huge and intricate net of power,among whose threads every character gets entangled.By deconstructing the configuration of power from two dimensions:body shame,the seen body,we are disclosed how power hierarchy is established.In Blasted,Kane deconstructs the power game by revealing its alienating effect on people,dissolves civilized humans:once stripped off the veneer of civilization,the repressed animality residing in humans would take hold and re⁃duce us to barbarians,still the play hints that humanistic love can function as a alternative to power in ruling the world.展开更多
With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic...With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic of various circles of society. In order to accelerate the poverty alleviation and provide references and recommendations for further development of theory and practice of financial poverty alleviation,this paper made an overview of the organization system,operation mechanism and service products of rural financial poverty alleviation,elaborated the development path of financial poverty alleviation,and came up with recommendations for financial poverty alleviation.展开更多
With the continuous advancement of economic globalization,energy demand is expanding and energy consumption is excessive,which leads to energy shortage.Unreasonable energy use also brings great challenges to the envir...With the continuous advancement of economic globalization,energy demand is expanding and energy consumption is excessive,which leads to energy shortage.Unreasonable energy use also brings great challenges to the environment and affects the balance of the ecosystem seriously.The rise of the third industrial revolution has injected new vitality into energy system.The construction of energy Internet system,which integrates Internet technology and energy technology,has become a new energy system of sustainable development.It has put forward the reform scheme for the mismatch of energy demand points and environmental pollution.The deepening of sustainable development strategy accelerates the promotion of energy Internet system,promotes the large-scale utilization and sharing of renewable energy.It also provides a new idea for realizing green energy structure and efficient energy utilization.Firstly,based on the core concept of energy Internet system,this paper reviews the relevant research on energy Internet system in academic and industrial circles,and gives the preliminary definition of energy Internet system market.On this basis,it puts forward the development goal of energy Internet system market.It compares the new energy Internet system market with the traditional single energy market,highlighting the characteristics of energy Internet system market,it is reflected in the diversified transformation of market trading subjects,the diversification of market trading objects,the increasing dependence of information technology and the improvement of the matching degree of supply and demand.Then,the integrated architecture of of the energy Internet system market is carried out,and the issues related to the transaction mode and operation mechanism of the energy Internet system market are discussed.Finally,the frontier problems of energy Internet system market are summarized,and the research prospect of energy Internet system market is put forward.展开更多
By virtue of the completeness of Wigner operator and Weyl correspondence we construct a general equation for deriving pure state density operators. Several important examples are considered as the applications of this...By virtue of the completeness of Wigner operator and Weyl correspondence we construct a general equation for deriving pure state density operators. Several important examples are considered as the applications of this equation, which shows that our approach is effective and convenient for deducing these entangled state representations.展开更多
Healthy development of agricultural science and technology parks needs perfect operation mechanism. On the basis of current situations,this paper came up with several safeguard measures for improving the operation mec...Healthy development of agricultural science and technology parks needs perfect operation mechanism. On the basis of current situations,this paper came up with several safeguard measures for improving the operation mechanism of agricultural science and technology parks,mainly including organization operation mechanism,technological guarantee mechanism,fund guarantee mechanism,and talent guarantee mechanism.展开更多
An islanding detection method in ungrounded power distribution system based on single-phase operating mechanisms of the circuit breaker(CB)is proposed in this paper.When CB opens three phase circuits to form an island...An islanding detection method in ungrounded power distribution system based on single-phase operating mechanisms of the circuit breaker(CB)is proposed in this paper.When CB opens three phase circuits to form an island,one phase circuit is opened firstly and the other two phase circuits are opened secondly after certain duration.During the period when only one phase circuit is opened,negative sequence voltage with certain duration is obtained at DG side because of the asymmetric operation of the system.After all three phase circuits are opened,the voltage variation direction of the two phases that are secondly disconnected from the grid follows the voltage variation direction of the firstly disconnected phase.Based on the above voltage characteristics,an islanding detection scheme is proposed to identify genuine islanding from system disturbances.The performance of the proposed scheme is tested in PSCAD/EMTDC using a 10 kV distribution network with synchronous DG interconnection.Simulation results demonstrate the proposed method is effective and reliable to detect islanding formation.展开更多
Reforms in public hospitals are among the most important improvements in China's health care system over the last two decades. However, the reforms that should be implemented in public hospitals are unclear. Thus, a ...Reforms in public hospitals are among the most important improvements in China's health care system over the last two decades. However, the reforms that should be implemented in public hospitals are unclear. Thus, a feasible direction of reforms in Chinese public hospitals is suggested and reliable policy suggestions are provided for the government to reform public hospitals. The data used in this study were mainly derived from a qualitative study. Focus group discussions and in-depth interviews were conducted in Shanghai, Guangdong, and Gansu between May and December 2014. Government funding accounted for approximately eight percent of the total annual revenue of public hospitals in China, and the insufficient government subsidy considerably affects the operation mechanism of public hospitals. However, solely increasing this subsidy cannot address the inappropriate incentives of public hospitals in China. The most crucial step in setting the direction of reforms in public hospitals in China is transforming inappropriate incentives by implementing a new evaluation index system for directors and physicians in public hospitals.展开更多
Various core memory devices have been proposed for utilization in future inmemory computing technology featuring high energy efficiency.Flash memory is considered as a viable choice owing to its high integration densi...Various core memory devices have been proposed for utilization in future inmemory computing technology featuring high energy efficiency.Flash memory is considered as a viable choice owing to its high integration density,stability,and reliability,which has been verified by commercialized products.However,its high operating voltage and slow operation speed issues caused by the tunneling mechanism make its adoption in in-memory computing applications difficult.In this paper,we introduce a dual-mode memory device named“ferro-floating memory”,fabricated using van der Waals(vdW)materials(h-BN,MoS2,andα-In2Se3).The vdW material,α-In2Se3,acts as a polarization control layer for the ferroelectric memory operation and charge storage layer for the conventional flash memory operation.Compared to the tunnelingbased memory operation,the ferro-floating memory operates 1.9 and 3.3 times faster at 6.7 and 5.8 times lower operating voltages for programming and erasing operations,respectively.The dual-mode operation improves the linearity of conductance change by 5 times and the dynamic range by 48%through achieving conductance variation regions.Furthermore,we assess the effects of the variation in device operating voltage on neural networks and suggest a memory array operating scheme for maximizing the networks'performance through various training/inference simulations.展开更多
This paper presents a distributed operating system modeled as an abstract machine that provides all the distributed processes with the same set of services.The kernel of our operating system supports ser- vices which ...This paper presents a distributed operating system modeled as an abstract machine that provides all the distributed processes with the same set of services.The kernel of our operating system supports ser- vices which are achieved by a remote procedure call on requests by parallel processes.Therefore,a scheme for solving the client-server relationship is required.In our system there are more than one cli- ents and,at least,a receive would he required for each.Similarly,there are more than one servers such that the send in a client should produce a message that can he received by every server. Consequently,a mechanism well suited for programming multiple-clients/single-server and sin- gle client/multiple-servers interactions is proposed.展开更多
基金supported by the NSFC HSR Fundamental Research Joint Fund (Grant No.U1934213)。
文摘Purpose-This study aims to research the large cross-section tunnel stability evaluation method corrected after considering the thickness-span ratio.Design/methodology/approach-First,taking the Liuyuan Tunnel of Huanggang-Huangmei High-Speed Railway as an example and taking deflection of the third principal stress of the surrounding rock at a vault after tunnel excavation as the criterion,the critical buried depth of the large section tunnel was determined.Then,the strength reduction method was employed to calculate the tunnel safety factor under different rock classes and thickness-span ratios,and mathematical statistics was conducted to identify the relationships of the tunnel safety factor with the thickness-span ratio and the basic quality(BQ)index of the rock for different rock classes.Finally,the influences of thickness-span ratio,groundwater,initial stress of rock and structural attitude factors were considered to obtain the corrected BQ,based on which the stability of a large cross-section tunnel with a depth of more than 100 m during mechanized operation was analyzed.This evaluation method was then applied to Liuyuan Tunnel and Cimushan No.2 Tunnel of Chongqing Urban Expressway for verification.Findings-This study shows that under different rock classes,the tunnel safety factor is a strict power function of the thickness-span ratio,while a linear function of the BQ to some extent.It is more suitable to use the corrected BQ as a quantitative index to evaluate tunnel stability according to the actual conditions of the site.Originality/value-The existing industry standards do not consider the influence of buried depth and span in the evaluation of tunnel stability.The stability evaluation method of large section tunnel considering the correction of overburden span ratio proposed in this paper achieves higher accuracy for the stability evaluation of surrounding rock in a full or large-section mechanized excavation of double line high-speed railway tunnels.
文摘Exploring the inner law of the economic operation of urbanization can understand the regulation mechanism of the optimal distribution of urban resource allocation. In this regard, we propose to explore and analyze the inner law of urbanization economic operation and its application. The study found that the urbanization economy originated from the urban agglomeration effect, which includes the agglomeration economic operation mechanism and spillover effect operation mechanism, based on which three kinds of inner laws of urbanization economic operation are explored, combined with the economic operation law, the non-equilibrium state of the declining cities are regulated and applied, and the results show that the analysis of the inner laws of urbanization economic operation has a direct significance in guiding the real economic process.
文摘With the rapid development of the market economy, complex changes have occurred in the market environment, and the competition among enterprises has become extremely fierce. The transformation of the structure of the market economy has prompted enterprises to seek for new developments and innovations. Under the background of the new economy, enterprises must begin from the perspective of internal management and internal strategic development to ensure quality enterprise operation mechanism innovation. This would help direct enterprise operation and development as well as demonstrate the value of enterprise internal management. In this way, enterprises will be able to array their overall competitiveness. This paper comprises a detailed analysis of the connotation and innovation of enterprise operation mechanism under the economic transformation, with the purpose of investigating the innovation strategy of enterprise operation mechanism under the economic transformation.
文摘Based on the theory of ecological organization,this paper analyzes the operation mechanism of chemical industry park(CIP)ecosystem by means of dynamic simulation.The research shows that the CIP ecosystem is a complex ecological system whose operation mechanism includes two levels,namely individual enterprises and ecosystem.At the level of individual enterprise,there are competition,symbiosis,invasion and other interactions between enterprises in the CIP ecosystem.Through the pre-determined judgment of the competition effect coefficient and the symbiosis effect coefficient,we calculate how the enterprises influence each other,and then generate their respective operation paths,andfinally realize the long-term balance of the system.At the level of ecosystem,the CIP ecosystem makes self-organizing and self-adaptive adjustments and changes due to the changes of the exter-nal environment in policy,manpower,technology,capital,market,etc.,thus reaching the equilibrium state of coordinated operation and stable symbiosis with the external environment.
文摘Stable operating region in the HL-1M tokamak has been extended by means of wall conditioning, core fuelling and current control techniques. The mechanisms of the extension are analyzed in this paper. Lithiumization diminishes the impurities and hydrogen recycling to the lowest level. After lithiumization a high density up to 7×1019 m-3 was obtained easily by strong gas puffing with ordinary ohmic discharge alone. More attractively we found that metal Li-coating exhibited the effects of wall stabilization. The low qα limit with higher density was extended by a factor of 1.5-2 in comparison with that for boronization, and 1.2 for siliconization. Siliconization not only extended stable operating region significantly by itself, but also provided a good target plasma for other experiments of raising density limit. Core fuelling schemes are favourable especially for siliconized wall with a higher level of medium-Z impurity (Z = 14). After siliconization the maximum density near to 1020 m-3 was achieved by a combination of supersonic molecule beam injection and multipellet injection. The new defined slope of Hugill limit illustrating more clearly the situation under low qα and high ne discharges was created to indicate the new region extended by combining IP ramp-up with core fuelling. The slope with a large Murakami coefficient increased by a factor of 50-60 %.
基金Supported by The 12 th Batch of Teaching Reform Research Project of Taishan University(201902).
文摘This paper studies the operation mechanism of crowdfunding for rural tourism from three aspects:the main body of crowdfunding for rural tourism,driving factors and operating stage.At the same time,this paper analyzes the operation risk of crowdfunding for rural tourism from five aspects:legal risk,information asymmetry risk,capital security risk,interest subject conflict risk and industry development risk.It also puts forward measures and suggestions on the promotion of crowdfunding for rural tourism from four aspects:improving market awareness,providing professional services,issuing relevant laws and regulations and regulating the development of the industry.
文摘The China National Textiles I/E Corp (Chinatex), one of the foreign trade companies in the country with the biggest import and export value, exported more textiles and expanded its business at home and abroad in 1994, in spite of the shortage of raw materials and the rise in prices. Chinatex’s import and export value totalled US$2.718 billion last year, a rise of 43.9% over the previous year. The quality of the exports also improved. The company’s Beijing branch exported US$370 million worth of goods, 33.3% more than in the previous year. Its enterprises abroad had a turnover of US$1 billion in 1994.
文摘According to customs statistics, China’s exports of machinery and electric products in 1996 were worth US$ 48.21 billion, an increase of 9.9 percent over the preceding year, and 8.4 percent higher than the growth rate of the nation’s total exports. The proportion of machinery and electric product exports in the nation’s total foreign trade volume\ increased from 29.5 percent in 1995 to 31.9 percent in 1996, a growth at 2.4 percent.
基金Project supported by the Doctoral Scientific Research Startup Fund of Anhui University,China (Grant No. 33190059)the National Natural Science Foundation of China (Grant No. 10874174)+1 种基金the Research Fund for the Doctoral Program of Higher Education of China (New Teacher) (Grant No. 20113401120004)the Open Funds from the National Laboratory for Infrared Physics,Chinese Academy of Sciences (Grant No. 201117)
文摘In terms of the coherent state evolution in phase space,we present a quantum mechanical version of the classical Liouville theorem.The evolution of the coherent state from |z〉to|sz-rz*〉 corresponds to the motion from a point z(q,p) to another point sz-rz* with |s|2-|r|2=1.The evolution is governed by the so-called Fresnel operator U(s,r) that was recently proposed in quantum optics theory,which classically corresponds to the matrix optics law and the optical Fresnel transformation,and obeys group product rules.In other words,we can recapitulate the Liouville theorem in the context of quantum mechanics by virtue of coherent state evolution in phase space,which seems to be a combination of quantum statistics and quantum optics.
文摘Blasted(1995)is knitted by Sarah Kane as a huge and intricate net of power,among whose threads every character gets entangled.By deconstructing the configuration of power from two dimensions:body shame,the seen body,we are disclosed how power hierarchy is established.In Blasted,Kane deconstructs the power game by revealing its alienating effect on people,dissolves civilized humans:once stripped off the veneer of civilization,the repressed animality residing in humans would take hold and re⁃duce us to barbarians,still the play hints that humanistic love can function as a alternative to power in ruling the world.
基金Supported by Bidding Project for Social Science Foundation of Hebei Agricultural University in 2017(ZB201702)Key Project of Humanities and Social Science Foundation of Hebei Provincial Department of Education(ZD201713)Social Science Foundation Project of Hebei Agricultural University(SK201604)
文摘With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic of various circles of society. In order to accelerate the poverty alleviation and provide references and recommendations for further development of theory and practice of financial poverty alleviation,this paper made an overview of the organization system,operation mechanism and service products of rural financial poverty alleviation,elaborated the development path of financial poverty alleviation,and came up with recommendations for financial poverty alleviation.
文摘With the continuous advancement of economic globalization,energy demand is expanding and energy consumption is excessive,which leads to energy shortage.Unreasonable energy use also brings great challenges to the environment and affects the balance of the ecosystem seriously.The rise of the third industrial revolution has injected new vitality into energy system.The construction of energy Internet system,which integrates Internet technology and energy technology,has become a new energy system of sustainable development.It has put forward the reform scheme for the mismatch of energy demand points and environmental pollution.The deepening of sustainable development strategy accelerates the promotion of energy Internet system,promotes the large-scale utilization and sharing of renewable energy.It also provides a new idea for realizing green energy structure and efficient energy utilization.Firstly,based on the core concept of energy Internet system,this paper reviews the relevant research on energy Internet system in academic and industrial circles,and gives the preliminary definition of energy Internet system market.On this basis,it puts forward the development goal of energy Internet system market.It compares the new energy Internet system market with the traditional single energy market,highlighting the characteristics of energy Internet system market,it is reflected in the diversified transformation of market trading subjects,the diversification of market trading objects,the increasing dependence of information technology and the improvement of the matching degree of supply and demand.Then,the integrated architecture of of the energy Internet system market is carried out,and the issues related to the transaction mode and operation mechanism of the energy Internet system market are discussed.Finally,the frontier problems of energy Internet system market are summarized,and the research prospect of energy Internet system market is put forward.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10874174 and 90203002)
文摘By virtue of the completeness of Wigner operator and Weyl correspondence we construct a general equation for deriving pure state density operators. Several important examples are considered as the applications of this equation, which shows that our approach is effective and convenient for deducing these entangled state representations.
基金Supported by Social Science Foundation Project of Shaanxi Province"Social Survey of the Northwest in the Period of the Republic of China"(2016H009)
文摘Healthy development of agricultural science and technology parks needs perfect operation mechanism. On the basis of current situations,this paper came up with several safeguard measures for improving the operation mechanism of agricultural science and technology parks,mainly including organization operation mechanism,technological guarantee mechanism,fund guarantee mechanism,and talent guarantee mechanism.
文摘An islanding detection method in ungrounded power distribution system based on single-phase operating mechanisms of the circuit breaker(CB)is proposed in this paper.When CB opens three phase circuits to form an island,one phase circuit is opened firstly and the other two phase circuits are opened secondly after certain duration.During the period when only one phase circuit is opened,negative sequence voltage with certain duration is obtained at DG side because of the asymmetric operation of the system.After all three phase circuits are opened,the voltage variation direction of the two phases that are secondly disconnected from the grid follows the voltage variation direction of the firstly disconnected phase.Based on the above voltage characteristics,an islanding detection scheme is proposed to identify genuine islanding from system disturbances.The performance of the proposed scheme is tested in PSCAD/EMTDC using a 10 kV distribution network with synchronous DG interconnection.Simulation results demonstrate the proposed method is effective and reliable to detect islanding formation.
文摘Reforms in public hospitals are among the most important improvements in China's health care system over the last two decades. However, the reforms that should be implemented in public hospitals are unclear. Thus, a feasible direction of reforms in Chinese public hospitals is suggested and reliable policy suggestions are provided for the government to reform public hospitals. The data used in this study were mainly derived from a qualitative study. Focus group discussions and in-depth interviews were conducted in Shanghai, Guangdong, and Gansu between May and December 2014. Government funding accounted for approximately eight percent of the total annual revenue of public hospitals in China, and the insufficient government subsidy considerably affects the operation mechanism of public hospitals. However, solely increasing this subsidy cannot address the inappropriate incentives of public hospitals in China. The most crucial step in setting the direction of reforms in public hospitals in China is transforming inappropriate incentives by implementing a new evaluation index system for directors and physicians in public hospitals.
基金National Research Foundation of Korea,Grant/Award Numbers:2020M3F3A2A02082436,2020R1A4A2002806,2021R1A2C2010026,2022M3F3A2A01072215Samsung Electronics Co.Ltd.,Grant/Award Number:IO201210-07994-01。
文摘Various core memory devices have been proposed for utilization in future inmemory computing technology featuring high energy efficiency.Flash memory is considered as a viable choice owing to its high integration density,stability,and reliability,which has been verified by commercialized products.However,its high operating voltage and slow operation speed issues caused by the tunneling mechanism make its adoption in in-memory computing applications difficult.In this paper,we introduce a dual-mode memory device named“ferro-floating memory”,fabricated using van der Waals(vdW)materials(h-BN,MoS2,andα-In2Se3).The vdW material,α-In2Se3,acts as a polarization control layer for the ferroelectric memory operation and charge storage layer for the conventional flash memory operation.Compared to the tunnelingbased memory operation,the ferro-floating memory operates 1.9 and 3.3 times faster at 6.7 and 5.8 times lower operating voltages for programming and erasing operations,respectively.The dual-mode operation improves the linearity of conductance change by 5 times and the dynamic range by 48%through achieving conductance variation regions.Furthermore,we assess the effects of the variation in device operating voltage on neural networks and suggest a memory array operating scheme for maximizing the networks'performance through various training/inference simulations.
基金The project supported by National Natural Science Foundation of China.
文摘This paper presents a distributed operating system modeled as an abstract machine that provides all the distributed processes with the same set of services.The kernel of our operating system supports ser- vices which are achieved by a remote procedure call on requests by parallel processes.Therefore,a scheme for solving the client-server relationship is required.In our system there are more than one cli- ents and,at least,a receive would he required for each.Similarly,there are more than one servers such that the send in a client should produce a message that can he received by every server. Consequently,a mechanism well suited for programming multiple-clients/single-server and sin- gle client/multiple-servers interactions is proposed.