Global food security is a pressing issue that affects the stability and well-being of communities worldwide.While existing Internet of Things(IoT)enabled plant monitoring systems have made significant strides in agric...Global food security is a pressing issue that affects the stability and well-being of communities worldwide.While existing Internet of Things(IoT)enabled plant monitoring systems have made significant strides in agricultural monitoring,they often face limitations such as high power consumption,restricted mobility,complex deployment requirements,and inadequate security measures for data access.This paper introduces an enhanced IoT application for agricultural monitoring systems that address these critical shortcomings.Our system strategically combines power efficiency,portability,and secure access capabilities,assisting farmers in monitoring and tracking crop environmental conditions.The proposed system includes a remote camera that captures images of surrounding plants and a sensor module that regularly monitors various environmental factors,including temperature,humidity,and soil moisture.We implement power management strategies to minimize energy consumption compared to existing solutions.Unlike conventional systems,our implementation utilizes the Amazon Web Services(AWS)cloud platform for reliable data storage and processing while incorporating comprehensive security measures,including Two-Factor Authentication(2FA)and JSON Web Tokens(JWT),features often overlooked in current agricultural IoT solutions.Users can access this secure monitoring system via a developed Android application,providing convenient mobile access to the gathered plant data.We validate our system’s advantages by implementing it with two potted garlic plants on Okayama University’s rooftop.Our evaluation demonstrates high sensor reliabil-ity,with strong correlations between sensor readings and reference data,achieving determination coefficients(R2)of 0.979 for temperature and 0.750 for humidity measurements.The implemented power management strategies extend battery life to 10 days on a single charge,significantly outperforming existing systems that typically require daily recharging.Furthermore,our dual-layer security implementation utilizing 2FA and JWT successfully protects sensitive agricultural data from unauthorized access.展开更多
Hydrogen challenge mitigation stands as one of the main objectives in the management of severe accidents at Nuclear Power Plants (NPPs). Key strategies for hydrogen control include atmospheric inertization and hydroge...Hydrogen challenge mitigation stands as one of the main objectives in the management of severe accidents at Nuclear Power Plants (NPPs). Key strategies for hydrogen control include atmospheric inertization and hydrogen removal with Passive Autocatalytic Recombiners (PARs) being a commonly accepted approach. However, an examination of PAR operation specificity reveals potential inefficiencies and reliability issues in certain severe accident scenarios. Moreover, during the in-vessel stage of severe accident development, in some severe accident scenarios PARs can unexpectedly become a source of hydrogen detonation. The effectiveness of hydrogen removal systems depends on various factors, including the chosen strategies, severe accident scenarios, reactor building design, and other influencing factors. Consequently, a comprehensive hydrogen mitigation strategy must effectively incorporate a combination of strategies rather than be based on one strategy, taking into consideration the probabilistic risks and uncertainties associated with the implementation of PARs or other traditional methods. In response to these considerations, within the framework of this research it has been suggested a conceptual strategy to mitigate the hydrogen challenge during the in-vessel stage of severe accident development.展开更多
This paper introduces the system structure and work principle of the upgraded real time information system in Wangting Power Plant, and then expounds the realization way and function features of this system on B/S co...This paper introduces the system structure and work principle of the upgraded real time information system in Wangting Power Plant, and then expounds the realization way and function features of this system on B/S computing mode. The results of field application show the new system has good capability, reliability and expandability.展开更多
In the context of both the Virtual Power Plant (VPP) and microgrid(MG), the Energy Management System (EMS) is a key decision-maker forintegrating Distributed renewable Energy Resources (DERs) efficiently. TheEMS is re...In the context of both the Virtual Power Plant (VPP) and microgrid(MG), the Energy Management System (EMS) is a key decision-maker forintegrating Distributed renewable Energy Resources (DERs) efficiently. TheEMS is regarded as a strong enabler of providing the optimized schedulingcontrol in operation and management of usage of disperse DERs and RenewableEnergy reSources (RES) such as a small-size wind-turbine (WT) andphotovoltaic (PV) energies. The main objective to be pursued by the EMSis the minimization of the overall operating cost of the MG integrated VPPnetwork. However, the minimization of the power peaks is a new objective andopen issue to a well-functional EMS, along with the maximization of profitin the energy market. Thus, both objectives have to be taken into accountat the same time. Thus, this paper proposes the EMS application incorporatingpower offering strategy applying a nature-inspired algorithm such asParticle Swarm Optimization (PSO) algorithm, in order to find the optimalsolution of the objective function in the context of the overall operating cost,the coordination of DERs, and the energy losses in a MG integrated VPPnetwork. For a fair DERs coordination with minimized power fluctuationsin the power flow, the power offering strategies with an active power controland re-distribution are proposed. Simulation results show that the proposedMG integrated VPP model with PSO-based EMS employing EgalitarianreDistribution (ED) power offering strategy is most feasible option for theoverall operating cost of VPP revenue. The total operating cost of the proposedEMS with ED strategy is 40.98$ compared to 432.8$ of MGs only withoutEMS. It is concluded that each MGs in the proposed VPP model intelligentlyparticipates in energy trading market compliant with the objective function,to minimize the overall cost and the power fluctuation.展开更多
In order to make management scientific, standard and intensive, more and more companies pay attention to plant management. Tlie system presented in this paper aims at helping NanHua Group Co. to improve its plant mana...In order to make management scientific, standard and intensive, more and more companies pay attention to plant management. Tlie system presented in this paper aims at helping NanHua Group Co. to improve its plant management level. This paper emphasizes the importance of plant management to NanHua Group Co. and mainly discusses the PMIS and how to implement plant management based on the contents of modern plant management. This part is the core of this paper. The final part sums up the research work and results.展开更多
The introduction of several small and large-scale industries,malls,shopping complexes,and domestic applications has significantly increased energy consumption.The aim of the work is to simulate a technically viable an...The introduction of several small and large-scale industries,malls,shopping complexes,and domestic applications has significantly increased energy consumption.The aim of the work is to simulate a technically viable and economically optimum hybrid power system for residential buildings.The proposed micro-grid model includes four power generators:solar power,wind power,Electricity Board(EB)source,and a Diesel Generator(DG)set,with solar and wind power performing as major sources and the EB supply and DG set serving as backup sources.The core issue in direct current to alternate current conversion is harmonics distortion,a five-stage multilevel inverter is employed with the assistance of an intelligent control system is simulated and the optimum system configuration is estimated to reduce harmonics and improve the power quality.The monthly demand for residential buildings is 13-15 Megawatts.So,almost 433 Kilo-Watts(KW)of electricity is required every day,and if it is used for 8 h per day,50-60 KW of electricity is needed per hour.The overall micro-grid model’s operation and performance are established using MATLAB/SIMULINK software,and simulation results are provided.The simulation results show that the developed system is both cost-effective and environment friendly resulting in yearly cost reductions.展开更多
From the background of small peasant management and information asymmetry,this paper introduced the middle profit sharing model and discussed influence factors and ownership of pricing power of agricultural products. ...From the background of small peasant management and information asymmetry,this paper introduced the middle profit sharing model and discussed influence factors and ownership of pricing power of agricultural products. It obtained following results:( i) the transaction scale has positive effect on farmer's pricing power of agricultural products,while the competitor's transaction scale has negative effect on it,so does the cost for information search;( ii) under the condition of small peasant management system,farmer is in a relatively weak position in the distribution of pricing power of agricultural products,due to factors such as small transaction scale,information asymmetry and farmer's weak negotiation ability;( iii) through cooperative game,farmer and buyers can share cooperative surplus at the agreed ratio;( iv) the introduction of self-organizing specialized farmers cooperatives is favorable for solving the problem of pricing power of agricultural products,and possible problems,such as " collective action dilemma" and " fake cooperatives" in the cooperative development process can be solved by internal and external division of labor and specialization of cooperatives.展开更多
Accompanying with the development of computer technology and network technology, enterprises have built their Intranet. This paper is dealing with how to construct the plant management information system based on Intr...Accompanying with the development of computer technology and network technology, enterprises have built their Intranet. This paper is dealing with how to construct the plant management information system based on Intranet, and lays emphasis on the subsystem division using structural system analysis and design method.展开更多
The nature of variable and uncertainty from renewable energy sources (RESs) makes them challenging to be integrated into the main grid separately. A Virtual Power Plant (VPP) is proposed to aggregate the capacities of...The nature of variable and uncertainty from renewable energy sources (RESs) makes them challenging to be integrated into the main grid separately. A Virtual Power Plant (VPP) is proposed to aggregate the capacities of RESs and facilitate the integration and management in a decentralized manner. In this paper, a novel framework for optimal energy management of VPP considering key features such as handling uncertainties with RESs, reducing operating costs and regulating system voltage levels is proposed, and a two-stage stochastic simulation is formulated to address the uncertainties of RESs generation and electricity prices. Simulation result show that the framework can benefit from ensuring the energy balance and system security, as well as reducing the operation costs.展开更多
The purpose of this study is to establish an intelligent expert system for nuclear power plant emergency response.A new framework of environmental risk management methodology by the concept of pattern recognition was ...The purpose of this study is to establish an intelligent expert system for nuclear power plant emergency response.A new framework of environmental risk management methodology by the concept of pattern recognition was introduced in this paper.A knowledge-based decision support system for emergency response and risk management of nuclear power plant was also discussed.The mathematical pattern relationship of accidental release effects on neighboring area and the corresponding response measures were presented in this paper.With this decision system,the decision maker can specify the procedure and minimize their human error in the decision process.The improvement of risk response and the quality of management system could be upgraded by this system.Besides,the methodology can also be served as a basis for the future development of environmental risk response system design.展开更多
A power allocation scheme for multi-user multiple-input multiple-output orthogonal frequency division multiplexing (MI- MO-OFDM) systems with channel state information (CSI) on transmitter and receiver is pressed....A power allocation scheme for multi-user multiple-input multiple-output orthogonal frequency division multiplexing (MI- MO-OFDM) systems with channel state information (CSI) on transmitter and receiver is pressed. Multi-user lower allocation can be decoupled into single user lower allocation throughout null space mapping of multi-user channel and lower allocation can be performed throughout spatial-spectral water-filling for per user.To deal with more users in system and fading correlation,scheduling is oerformed to maintain the gain of power allocation.The proposed scheme can substantially improve system's spectral efficiency with low complexity.Simulation results validate the accuracy of theoretic analyses.展开更多
Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life...Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life of RPV, and thus, the aging and life research on a RPV is a key factor in determining the life extension of NPPs. The purpose of this paper is to introduce an aging and life management system for an operating RPV which can be used as a reference of the lifetime extension. In order to realize the objective, an aging and life management system was developed. It is an comprehensive knowledge management system that integrates decentralized information and serves as a valuable data center. Based on the storage and management of RPV state information and operation data, this system provides real-time monitoring of important operating parameters, evaluation of irradiation embrittlement, and RPV aging assessment. Therefore, it is anticipated that the developed system can be used as an efficient tool for aging and life estimation of RPV.展开更多
In the last few decades, in the world and also in the European Union, considerable resources had been invested in the rapid development of renewable energy sources and distributed generation in general. At the same ti...In the last few decades, in the world and also in the European Union, considerable resources had been invested in the rapid development of renewable energy sources and distributed generation in general. At the same time, power consumption is continuously increasing, and consumers are becoming more complex, which ultimately requires new investments in the distribution network. Concept of smart grids is generally accepted as a possible solution. Smart grid is a concept with many elements, where monitoring and control of every element in the chain of production, transmission, distribution and final consumption enable much more efficient delivery and use of electricity. One of the elements of smart grid efficiency is the ability of real-time demand-supply balancing. This balancing is carried out by monitoring of consumption and redistribution of electricity among individual end users, according to their needs. The aim of this paper is creating algorithm for real-time load management using power measurements. Algorithm for real-time load management at the ETFOS (Faculty of Electrical Engineering in Osijek), Croatia is created based on measurements of photovoltaic power plant production, the power consumption of air conditioning system and the faculty building total electricity consumption. Expected result of real-time re-dispatching of air conditioners consumption, depending on the level of electricity production in photovoltaic power plant is decreasing peak demand of the faculty.展开更多
Regarding the technical management during construction of Thailand PTA Co-generation, there are some problems due to the typical method in electric power construction in China, which show the differences between inter...Regarding the technical management during construction of Thailand PTA Co-generation, there are some problems due to the typical method in electric power construction in China, which show the differences between international methods and ours. In order to do the technical management in the project for export contract, it is necessary to do the work based on the Contract, to know the related laws and regulations, and national conditions, to coordinate the relationship among various parties well, and to carry out the management ahead of time.展开更多
Heliothermic electricity generation is gaining popularity in several countries worldwide. In Brazil, this form of energy generation has not yet been explored for large scale projects. However, the country possesses ex...Heliothermic electricity generation is gaining popularity in several countries worldwide. In Brazil, this form of energy generation has not yet been explored for large scale projects. However, the country possesses extensive areas with normal and high-intensity direct irradiation and low seasonality factors, particularly in the semi-arid region of the Brazilian Northeast. The region also presents other important features for setting up such plants: proximity to transmission lines, sufficient flatness, non-endangered vegetation, a suitable land use profile low maximum wind speeds, low population density, and more recently, an increase in the demand for local electric energy due to economic growth above the Brazilian average. A Geographic Information System includes a set of specialised resources that allow us to manipulate spatial data, providing quickness and efficiency in the identification of appropriate places for installing solar power plants while also preparing us for future scenarios, with regards to their impacts, costs and benefits. This article presents a study of the optimal location for thermoelectric power plants in the semi-arid region of the Brazilian Northeast on the scale of 1:10,000,000. All provinces with good potential for the implementation of large-scale concentrating solar power plants are identified. Considering that the installed capacity for parabolic cylindrical concentrators in terrains with a steepness of less than 1% is 43.26 MW/km2 for systems without storage and 30.82 MW/km2 for systems with 6 hours of storage, the potential of the southeast region of Piauí alone is huge. Even with the lack of information about the urban areas, terrain continuity, and other variables,utilising only 10% of the identified potential area, or879.7 km2, would result in an installed capacity of 38.1-27.1 GW. This value corresponds to more than 1/3 of the potency of the current Brazilian electric system. If the same calculation is made for the semi-arid region of the Brazilian Northeast, its capacity will be greater than 1000 GW.展开更多
This paper presents main results of a comprehensive study performed by the European Clearinghouse on Operating Experience Feedback of NPP with the support of IRSN (Institut de S?reté Nucléaire et de Radiopro...This paper presents main results of a comprehensive study performed by the European Clearinghouse on Operating Experience Feedback of NPP with the support of IRSN (Institut de S?reté Nucléaire et de Radioprotection) and GRS (Gesellschaft für Anlagen und Reaktorsi-cherheit mbH). Physical ageing mechanisms of structure, systems and components that eventually lead to ageing related systems and components failures at nuclear power plants were the main focus of this study. The analysis of ageing related events involved operating experience reported by NPP operators in France, Germany, USA and to the IAEA/NEA International Reporting system, on operating experience for the past 20 years (i.e. 1990-2009). A list of ageing related events was populated. Each ageing related event contained in the list was analyzed and results of analysis were summarized for each commodity group for which the ageing degradation appeared to be a dominant contributor or direct cause. The most common degradation mechanisms/ageing effects for each specific component/commodity group, their risk significance and consequences to the plant performance are described. This paper provides insights into ageing related operating experience as well as recommendations to deal with the physical ageing of nuclear power plant SSC important to safety.展开更多
Both opportunities and challenges are currently faced by government management innovation in the age of "big data". Traditionally, relative studies view the management of governments as the effective means to improv...Both opportunities and challenges are currently faced by government management innovation in the age of "big data". Traditionally, relative studies view the management of governments as the effective means to improve governmental services, without really understanding the structural influence of big data and network technology on governmental mode of thinking. Against such backdrop, this paper tries to conduct critical analysis based upon traditional outcomes in this regard, trying to make full use of the function of big data technology. With these efforts, this paper contributes to the building of an interaction theory that could promote transparency of information and customization and segmentation of the policies. By constructing a mode in which management could be carried out based on the law of big data, by building an information management system in which balance could be achieved between responsibility and freedom, by promoting the rebalancing among public power, online civil society and civil rights, the innovation of governmental management would be achieved.展开更多
基金supported by the budget of GIC project at Okayama University.
文摘Global food security is a pressing issue that affects the stability and well-being of communities worldwide.While existing Internet of Things(IoT)enabled plant monitoring systems have made significant strides in agricultural monitoring,they often face limitations such as high power consumption,restricted mobility,complex deployment requirements,and inadequate security measures for data access.This paper introduces an enhanced IoT application for agricultural monitoring systems that address these critical shortcomings.Our system strategically combines power efficiency,portability,and secure access capabilities,assisting farmers in monitoring and tracking crop environmental conditions.The proposed system includes a remote camera that captures images of surrounding plants and a sensor module that regularly monitors various environmental factors,including temperature,humidity,and soil moisture.We implement power management strategies to minimize energy consumption compared to existing solutions.Unlike conventional systems,our implementation utilizes the Amazon Web Services(AWS)cloud platform for reliable data storage and processing while incorporating comprehensive security measures,including Two-Factor Authentication(2FA)and JSON Web Tokens(JWT),features often overlooked in current agricultural IoT solutions.Users can access this secure monitoring system via a developed Android application,providing convenient mobile access to the gathered plant data.We validate our system’s advantages by implementing it with two potted garlic plants on Okayama University’s rooftop.Our evaluation demonstrates high sensor reliabil-ity,with strong correlations between sensor readings and reference data,achieving determination coefficients(R2)of 0.979 for temperature and 0.750 for humidity measurements.The implemented power management strategies extend battery life to 10 days on a single charge,significantly outperforming existing systems that typically require daily recharging.Furthermore,our dual-layer security implementation utilizing 2FA and JWT successfully protects sensitive agricultural data from unauthorized access.
文摘Hydrogen challenge mitigation stands as one of the main objectives in the management of severe accidents at Nuclear Power Plants (NPPs). Key strategies for hydrogen control include atmospheric inertization and hydrogen removal with Passive Autocatalytic Recombiners (PARs) being a commonly accepted approach. However, an examination of PAR operation specificity reveals potential inefficiencies and reliability issues in certain severe accident scenarios. Moreover, during the in-vessel stage of severe accident development, in some severe accident scenarios PARs can unexpectedly become a source of hydrogen detonation. The effectiveness of hydrogen removal systems depends on various factors, including the chosen strategies, severe accident scenarios, reactor building design, and other influencing factors. Consequently, a comprehensive hydrogen mitigation strategy must effectively incorporate a combination of strategies rather than be based on one strategy, taking into consideration the probabilistic risks and uncertainties associated with the implementation of PARs or other traditional methods. In response to these considerations, within the framework of this research it has been suggested a conceptual strategy to mitigate the hydrogen challenge during the in-vessel stage of severe accident development.
文摘This paper introduces the system structure and work principle of the upgraded real time information system in Wangting Power Plant, and then expounds the realization way and function features of this system on B/S computing mode. The results of field application show the new system has good capability, reliability and expandability.
文摘In the context of both the Virtual Power Plant (VPP) and microgrid(MG), the Energy Management System (EMS) is a key decision-maker forintegrating Distributed renewable Energy Resources (DERs) efficiently. TheEMS is regarded as a strong enabler of providing the optimized schedulingcontrol in operation and management of usage of disperse DERs and RenewableEnergy reSources (RES) such as a small-size wind-turbine (WT) andphotovoltaic (PV) energies. The main objective to be pursued by the EMSis the minimization of the overall operating cost of the MG integrated VPPnetwork. However, the minimization of the power peaks is a new objective andopen issue to a well-functional EMS, along with the maximization of profitin the energy market. Thus, both objectives have to be taken into accountat the same time. Thus, this paper proposes the EMS application incorporatingpower offering strategy applying a nature-inspired algorithm such asParticle Swarm Optimization (PSO) algorithm, in order to find the optimalsolution of the objective function in the context of the overall operating cost,the coordination of DERs, and the energy losses in a MG integrated VPPnetwork. For a fair DERs coordination with minimized power fluctuationsin the power flow, the power offering strategies with an active power controland re-distribution are proposed. Simulation results show that the proposedMG integrated VPP model with PSO-based EMS employing EgalitarianreDistribution (ED) power offering strategy is most feasible option for theoverall operating cost of VPP revenue. The total operating cost of the proposedEMS with ED strategy is 40.98$ compared to 432.8$ of MGs only withoutEMS. It is concluded that each MGs in the proposed VPP model intelligentlyparticipates in energy trading market compliant with the objective function,to minimize the overall cost and the power fluctuation.
文摘In order to make management scientific, standard and intensive, more and more companies pay attention to plant management. Tlie system presented in this paper aims at helping NanHua Group Co. to improve its plant management level. This paper emphasizes the importance of plant management to NanHua Group Co. and mainly discusses the PMIS and how to implement plant management based on the contents of modern plant management. This part is the core of this paper. The final part sums up the research work and results.
文摘The introduction of several small and large-scale industries,malls,shopping complexes,and domestic applications has significantly increased energy consumption.The aim of the work is to simulate a technically viable and economically optimum hybrid power system for residential buildings.The proposed micro-grid model includes four power generators:solar power,wind power,Electricity Board(EB)source,and a Diesel Generator(DG)set,with solar and wind power performing as major sources and the EB supply and DG set serving as backup sources.The core issue in direct current to alternate current conversion is harmonics distortion,a five-stage multilevel inverter is employed with the assistance of an intelligent control system is simulated and the optimum system configuration is estimated to reduce harmonics and improve the power quality.The monthly demand for residential buildings is 13-15 Megawatts.So,almost 433 Kilo-Watts(KW)of electricity is required every day,and if it is used for 8 h per day,50-60 KW of electricity is needed per hour.The overall micro-grid model’s operation and performance are established using MATLAB/SIMULINK software,and simulation results are provided.The simulation results show that the developed system is both cost-effective and environment friendly resulting in yearly cost reductions.
文摘From the background of small peasant management and information asymmetry,this paper introduced the middle profit sharing model and discussed influence factors and ownership of pricing power of agricultural products. It obtained following results:( i) the transaction scale has positive effect on farmer's pricing power of agricultural products,while the competitor's transaction scale has negative effect on it,so does the cost for information search;( ii) under the condition of small peasant management system,farmer is in a relatively weak position in the distribution of pricing power of agricultural products,due to factors such as small transaction scale,information asymmetry and farmer's weak negotiation ability;( iii) through cooperative game,farmer and buyers can share cooperative surplus at the agreed ratio;( iv) the introduction of self-organizing specialized farmers cooperatives is favorable for solving the problem of pricing power of agricultural products,and possible problems,such as " collective action dilemma" and " fake cooperatives" in the cooperative development process can be solved by internal and external division of labor and specialization of cooperatives.
文摘Accompanying with the development of computer technology and network technology, enterprises have built their Intranet. This paper is dealing with how to construct the plant management information system based on Intranet, and lays emphasis on the subsystem division using structural system analysis and design method.
文摘The nature of variable and uncertainty from renewable energy sources (RESs) makes them challenging to be integrated into the main grid separately. A Virtual Power Plant (VPP) is proposed to aggregate the capacities of RESs and facilitate the integration and management in a decentralized manner. In this paper, a novel framework for optimal energy management of VPP considering key features such as handling uncertainties with RESs, reducing operating costs and regulating system voltage levels is proposed, and a two-stage stochastic simulation is formulated to address the uncertainties of RESs generation and electricity prices. Simulation result show that the framework can benefit from ensuring the energy balance and system security, as well as reducing the operation costs.
基金Supported by Jinwen University of Science and Technology
文摘The purpose of this study is to establish an intelligent expert system for nuclear power plant emergency response.A new framework of environmental risk management methodology by the concept of pattern recognition was introduced in this paper.A knowledge-based decision support system for emergency response and risk management of nuclear power plant was also discussed.The mathematical pattern relationship of accidental release effects on neighboring area and the corresponding response measures were presented in this paper.With this decision system,the decision maker can specify the procedure and minimize their human error in the decision process.The improvement of risk response and the quality of management system could be upgraded by this system.Besides,the methodology can also be served as a basis for the future development of environmental risk response system design.
基金This project was supported bythe National Natural Science Foundation of China (60272079) the National High Technol-ogy Research and Development Plan Project of China (2001AA123014) .
文摘A power allocation scheme for multi-user multiple-input multiple-output orthogonal frequency division multiplexing (MI- MO-OFDM) systems with channel state information (CSI) on transmitter and receiver is pressed. Multi-user lower allocation can be decoupled into single user lower allocation throughout null space mapping of multi-user channel and lower allocation can be performed throughout spatial-spectral water-filling for per user.To deal with more users in system and fading correlation,scheduling is oerformed to maintain the gain of power allocation.The proposed scheme can substantially improve system's spectral efficiency with low complexity.Simulation results validate the accuracy of theoretic analyses.
文摘Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life of RPV, and thus, the aging and life research on a RPV is a key factor in determining the life extension of NPPs. The purpose of this paper is to introduce an aging and life management system for an operating RPV which can be used as a reference of the lifetime extension. In order to realize the objective, an aging and life management system was developed. It is an comprehensive knowledge management system that integrates decentralized information and serves as a valuable data center. Based on the storage and management of RPV state information and operation data, this system provides real-time monitoring of important operating parameters, evaluation of irradiation embrittlement, and RPV aging assessment. Therefore, it is anticipated that the developed system can be used as an efficient tool for aging and life estimation of RPV.
文摘In the last few decades, in the world and also in the European Union, considerable resources had been invested in the rapid development of renewable energy sources and distributed generation in general. At the same time, power consumption is continuously increasing, and consumers are becoming more complex, which ultimately requires new investments in the distribution network. Concept of smart grids is generally accepted as a possible solution. Smart grid is a concept with many elements, where monitoring and control of every element in the chain of production, transmission, distribution and final consumption enable much more efficient delivery and use of electricity. One of the elements of smart grid efficiency is the ability of real-time demand-supply balancing. This balancing is carried out by monitoring of consumption and redistribution of electricity among individual end users, according to their needs. The aim of this paper is creating algorithm for real-time load management using power measurements. Algorithm for real-time load management at the ETFOS (Faculty of Electrical Engineering in Osijek), Croatia is created based on measurements of photovoltaic power plant production, the power consumption of air conditioning system and the faculty building total electricity consumption. Expected result of real-time re-dispatching of air conditioners consumption, depending on the level of electricity production in photovoltaic power plant is decreasing peak demand of the faculty.
文摘Regarding the technical management during construction of Thailand PTA Co-generation, there are some problems due to the typical method in electric power construction in China, which show the differences between international methods and ours. In order to do the technical management in the project for export contract, it is necessary to do the work based on the Contract, to know the related laws and regulations, and national conditions, to coordinate the relationship among various parties well, and to carry out the management ahead of time.
基金the ConselhoNacional de Pesquisa(CNPq),Centrais Eletricas Brasileiras S.A.(ELETRO-BRAS),Companhia Hidro Eletrica do Sao Francisco(CHESF)and Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior(CAPES)for their support to the solar energy research projects,which have provided the material means and the scientific environment for the execution of this research.
文摘Heliothermic electricity generation is gaining popularity in several countries worldwide. In Brazil, this form of energy generation has not yet been explored for large scale projects. However, the country possesses extensive areas with normal and high-intensity direct irradiation and low seasonality factors, particularly in the semi-arid region of the Brazilian Northeast. The region also presents other important features for setting up such plants: proximity to transmission lines, sufficient flatness, non-endangered vegetation, a suitable land use profile low maximum wind speeds, low population density, and more recently, an increase in the demand for local electric energy due to economic growth above the Brazilian average. A Geographic Information System includes a set of specialised resources that allow us to manipulate spatial data, providing quickness and efficiency in the identification of appropriate places for installing solar power plants while also preparing us for future scenarios, with regards to their impacts, costs and benefits. This article presents a study of the optimal location for thermoelectric power plants in the semi-arid region of the Brazilian Northeast on the scale of 1:10,000,000. All provinces with good potential for the implementation of large-scale concentrating solar power plants are identified. Considering that the installed capacity for parabolic cylindrical concentrators in terrains with a steepness of less than 1% is 43.26 MW/km2 for systems without storage and 30.82 MW/km2 for systems with 6 hours of storage, the potential of the southeast region of Piauí alone is huge. Even with the lack of information about the urban areas, terrain continuity, and other variables,utilising only 10% of the identified potential area, or879.7 km2, would result in an installed capacity of 38.1-27.1 GW. This value corresponds to more than 1/3 of the potency of the current Brazilian electric system. If the same calculation is made for the semi-arid region of the Brazilian Northeast, its capacity will be greater than 1000 GW.
文摘This paper presents main results of a comprehensive study performed by the European Clearinghouse on Operating Experience Feedback of NPP with the support of IRSN (Institut de S?reté Nucléaire et de Radioprotection) and GRS (Gesellschaft für Anlagen und Reaktorsi-cherheit mbH). Physical ageing mechanisms of structure, systems and components that eventually lead to ageing related systems and components failures at nuclear power plants were the main focus of this study. The analysis of ageing related events involved operating experience reported by NPP operators in France, Germany, USA and to the IAEA/NEA International Reporting system, on operating experience for the past 20 years (i.e. 1990-2009). A list of ageing related events was populated. Each ageing related event contained in the list was analyzed and results of analysis were summarized for each commodity group for which the ageing degradation appeared to be a dominant contributor or direct cause. The most common degradation mechanisms/ageing effects for each specific component/commodity group, their risk significance and consequences to the plant performance are described. This paper provides insights into ageing related operating experience as well as recommendations to deal with the physical ageing of nuclear power plant SSC important to safety.
文摘Both opportunities and challenges are currently faced by government management innovation in the age of "big data". Traditionally, relative studies view the management of governments as the effective means to improve governmental services, without really understanding the structural influence of big data and network technology on governmental mode of thinking. Against such backdrop, this paper tries to conduct critical analysis based upon traditional outcomes in this regard, trying to make full use of the function of big data technology. With these efforts, this paper contributes to the building of an interaction theory that could promote transparency of information and customization and segmentation of the policies. By constructing a mode in which management could be carried out based on the law of big data, by building an information management system in which balance could be achieved between responsibility and freedom, by promoting the rebalancing among public power, online civil society and civil rights, the innovation of governmental management would be achieved.