Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electric...Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electricity price combined with state of charge is proposed to optimize the economic operation of wind and solar microgrids,and the optimal allocation of energy storage capacity is carried out by using this strategy.Firstly,the structure and model of microgrid are analyzed,and the outputmodel of wind power,photovoltaic and energy storage is established.Then,considering the interactive power cost between the microgrid and the main grid and the charge-discharge penalty cost of energy storage,an optimization objective function is established,and an improved energy management strategy is proposed on this basis.Finally,a physicalmodel is built inMATLAB/Simulink for simulation verification,and the energy management strategy is compared and analyzed on sunny and rainy days.The initial configuration cost function of energy storage is added to optimize the allocation of energy storage capacity.The simulation results show that the improved energy management strategy can make the battery charge-discharge response to real-time electricity price and state of charge better than the traditional strategy on sunny or rainy days,reduce the interactive power cost between the microgrid system and the power grid.After analyzing the change of energy storage power with cost,we obtain the best energy storage capacity and energy storage power.展开更多
Objective To evaluate the effect of some policies to prevent drug shortage and stabilize drug prices,and to provide reference for improving relevant policies.Methods With a combination of random stratified sampling an...Objective To evaluate the effect of some policies to prevent drug shortage and stabilize drug prices,and to provide reference for improving relevant policies.Methods With a combination of random stratified sampling and quota sampling,532 medical institutions in 20 provinces were selected to carry out questionnaire surveys.Then,a comparative analysis was made to study the changes of drugs on the shortage list and drugs on non-shortage list before and after the release of the policy of ensuring supply and stabilizing prices.Results and Conclusion The policy played an important role in curbing the growth of drug shortage in the medical institutions,but it did not curb the growth of drugs on non-shortage list.Besides,the drugs on non-shortage list showed an overall fluctuation and upward trend.Meanwhile,from the perspective of drug prices,the price stability problem of drugs on the shortage list and on the non-shortage list became more serious,and the average price increase was 256% and 239%,respectively.The implementation of policies related to the supply and price stability of drugs prevents the growth trend of drug shortages in the list of medical institutions,which has been recognized by most medical institutions.However,there is an increasing trend in the number of drugs on non-shortage list.In addition,the price increase of drugs on both the shortage list and non-shortage list is severe.Some medical institutions report that they have difficulties in using the information reporting system of drug shortage and the classification,grading and the alternative use of drug shortages.It is recommended to strengthen the management of price stabilization of drugs on the shortage list.Further attention should be paid to the supply and price stabilization of drugs on non-shortage list.At the same time,trainings in the classification and substitution of drug shortage and information reporting system should be actively organized,thus comprehensively improving the capabilities of medical institutions at all levels to deal with the problem of drug shortage.展开更多
网络直播广告作为一种新型营销方式快速发展,优化直播广告运营主体努力水平及定价策略是一项值得深入研究的课题。本文基于广告投放效果的两种定价模式,构建了包含两个广告商和一个主播的网络直播广告定价决策模型,探索广告商与主播的...网络直播广告作为一种新型营销方式快速发展,优化直播广告运营主体努力水平及定价策略是一项值得深入研究的课题。本文基于广告投放效果的两种定价模式,构建了包含两个广告商和一个主播的网络直播广告定价决策模型,探索广告商与主播的最优努力水平选择及广告定价策略。研究发现:CPW(cost per watch)定价模式下,广告商承担了消费者是否购买的不确定性风险,当消费者敏感性系数偏低时,广告商会提交较低的出价,且B/D两类广告商赢得竞拍的概率相等;对比CPW模式,在CPA(cost per action)定价模式下广告商的努力水平更低,且CPA定价模式中B型(品牌型)广告商赢得竞拍的概率更大,但赢得竞拍的广告商边际利润往往较低;与广告商相反,主播在CPA定价模式下的收益大于CPW,且随消费者敏感性系数的增加,两种定价模式下的收益差逐渐增大;CPW定价模式下预期观看直播的用户量和购买率均高于CPA,网络直播市场倾向于从CPW广告定价合同中获得较大收益。展开更多
基金a phased achievement of Gansu Province’s Major Science and Technology Project(W22KJ2722005)“Research on Optimal Configuration and Operation Strategy of Energy Storage under“New Energy+Energy Storage”Mode”.
文摘Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electricity price combined with state of charge is proposed to optimize the economic operation of wind and solar microgrids,and the optimal allocation of energy storage capacity is carried out by using this strategy.Firstly,the structure and model of microgrid are analyzed,and the outputmodel of wind power,photovoltaic and energy storage is established.Then,considering the interactive power cost between the microgrid and the main grid and the charge-discharge penalty cost of energy storage,an optimization objective function is established,and an improved energy management strategy is proposed on this basis.Finally,a physicalmodel is built inMATLAB/Simulink for simulation verification,and the energy management strategy is compared and analyzed on sunny and rainy days.The initial configuration cost function of energy storage is added to optimize the allocation of energy storage capacity.The simulation results show that the improved energy management strategy can make the battery charge-discharge response to real-time electricity price and state of charge better than the traditional strategy on sunny or rainy days,reduce the interactive power cost between the microgrid system and the power grid.After analyzing the change of energy storage power with cost,we obtain the best energy storage capacity and energy storage power.
文摘Objective To evaluate the effect of some policies to prevent drug shortage and stabilize drug prices,and to provide reference for improving relevant policies.Methods With a combination of random stratified sampling and quota sampling,532 medical institutions in 20 provinces were selected to carry out questionnaire surveys.Then,a comparative analysis was made to study the changes of drugs on the shortage list and drugs on non-shortage list before and after the release of the policy of ensuring supply and stabilizing prices.Results and Conclusion The policy played an important role in curbing the growth of drug shortage in the medical institutions,but it did not curb the growth of drugs on non-shortage list.Besides,the drugs on non-shortage list showed an overall fluctuation and upward trend.Meanwhile,from the perspective of drug prices,the price stability problem of drugs on the shortage list and on the non-shortage list became more serious,and the average price increase was 256% and 239%,respectively.The implementation of policies related to the supply and price stability of drugs prevents the growth trend of drug shortages in the list of medical institutions,which has been recognized by most medical institutions.However,there is an increasing trend in the number of drugs on non-shortage list.In addition,the price increase of drugs on both the shortage list and non-shortage list is severe.Some medical institutions report that they have difficulties in using the information reporting system of drug shortage and the classification,grading and the alternative use of drug shortages.It is recommended to strengthen the management of price stabilization of drugs on the shortage list.Further attention should be paid to the supply and price stabilization of drugs on non-shortage list.At the same time,trainings in the classification and substitution of drug shortage and information reporting system should be actively organized,thus comprehensively improving the capabilities of medical institutions at all levels to deal with the problem of drug shortage.
文摘网络直播广告作为一种新型营销方式快速发展,优化直播广告运营主体努力水平及定价策略是一项值得深入研究的课题。本文基于广告投放效果的两种定价模式,构建了包含两个广告商和一个主播的网络直播广告定价决策模型,探索广告商与主播的最优努力水平选择及广告定价策略。研究发现:CPW(cost per watch)定价模式下,广告商承担了消费者是否购买的不确定性风险,当消费者敏感性系数偏低时,广告商会提交较低的出价,且B/D两类广告商赢得竞拍的概率相等;对比CPW模式,在CPA(cost per action)定价模式下广告商的努力水平更低,且CPA定价模式中B型(品牌型)广告商赢得竞拍的概率更大,但赢得竞拍的广告商边际利润往往较低;与广告商相反,主播在CPA定价模式下的收益大于CPW,且随消费者敏感性系数的增加,两种定价模式下的收益差逐渐增大;CPW定价模式下预期观看直播的用户量和购买率均高于CPA,网络直播市场倾向于从CPW广告定价合同中获得较大收益。
