Most of the questions from users lack the context needed to thoroughly understand the problemat hand,thus making the questions impossible to answer.Semantic Similarity Estimation is based on relating user’s questions...Most of the questions from users lack the context needed to thoroughly understand the problemat hand,thus making the questions impossible to answer.Semantic Similarity Estimation is based on relating user’s questions to the context from previous Conversational Search Systems(CSS)to provide answers without requesting the user’s context.It imposes constraints on the time needed to produce an answer for the user.The proposed model enables the use of contextual data associated with previous Conversational Searches(CS).While receiving a question in a new conversational search,the model determines the question that refers tomore pastCS.Themodel then infers past contextual data related to the given question and predicts an answer based on the context inferred without engaging in multi-turn interactions or requesting additional data from the user for context.This model shows the ability to use the limited information in user queries for best context inferences based on Closed-Domain-based CS and Bidirectional Encoder Representations from Transformers for textual representations.展开更多
For the past few years,wind energy is the most popular non-traditional resource among renewable energy resources and it’s significant to make full use of wind energy to realize a high level of generating power.Moreov...For the past few years,wind energy is the most popular non-traditional resource among renewable energy resources and it’s significant to make full use of wind energy to realize a high level of generating power.Moreover,diverse maximum power point tracking(MPPT)methods have been designed for varying speed operation of wind energy conversion system(WECS)applications to obtain optimal power extraction.Hence,a novel and metaheuristic technique,named enhanced atom search optimization(EASO),is designed for a permanent magnet synchronous generator(PMSG)based WECS,which can be employed to track the maximum power point.One of the most promising benefits of this technique is powerful global search capability that leads to fast response and high-quality optimal solution.Besides,in contrast with other conventional meta-heuristic techniques,EASO is extremely not relying on the original solution,which can avoid sinking into a low-quality local maximum power point(LMPP)by realizing an appropriate trade-off between global exploration and local exploitation.At last,simulations employing two case studies through Matlab/Simulink validate the practicability and effectiveness of the proposed techniques for optimal proportional-integral-derivative(PID)control parameters tuning of PMSG based WECS under a variety of wind conditions.展开更多
针对爬山法(hill-climbing searching,HCS)在最大功率点(maximum power point,MPP)处存在的转速振荡和风速变化导致搜索方向误判的问题,提出1种具有扰动停止机制的改进爬山算法。该算法不仅继承了变步长爬山法快速搜索至MPP附近的优点,...针对爬山法(hill-climbing searching,HCS)在最大功率点(maximum power point,MPP)处存在的转速振荡和风速变化导致搜索方向误判的问题,提出1种具有扰动停止机制的改进爬山算法。该算法不仅继承了变步长爬山法快速搜索至MPP附近的优点,还具有MPP检测和停止机制。在风机跟踪至MPP附近时,该机制不仅可以有效降低转速振荡对风机系统机械部件的磨损,而且克服了算法停止机制生效后风速再次变化时对搜索方向判断的干扰,从而进一步提高了风能捕获效率。在简化风电系统模型的基础上,仿真结果验证了该算法的有效性和优越性。展开更多
文摘Most of the questions from users lack the context needed to thoroughly understand the problemat hand,thus making the questions impossible to answer.Semantic Similarity Estimation is based on relating user’s questions to the context from previous Conversational Search Systems(CSS)to provide answers without requesting the user’s context.It imposes constraints on the time needed to produce an answer for the user.The proposed model enables the use of contextual data associated with previous Conversational Searches(CS).While receiving a question in a new conversational search,the model determines the question that refers tomore pastCS.Themodel then infers past contextual data related to the given question and predicts an answer based on the context inferred without engaging in multi-turn interactions or requesting additional data from the user for context.This model shows the ability to use the limited information in user queries for best context inferences based on Closed-Domain-based CS and Bidirectional Encoder Representations from Transformers for textual representations.
基金The authors appreciatively acknowledge the support of rapid device state variation based system device invention of a training device for live-work electricity meter installation without electric shocks(YNZC202003110011)National Natural Science Foundation of China(NSFC)under Grant(61902039).
文摘For the past few years,wind energy is the most popular non-traditional resource among renewable energy resources and it’s significant to make full use of wind energy to realize a high level of generating power.Moreover,diverse maximum power point tracking(MPPT)methods have been designed for varying speed operation of wind energy conversion system(WECS)applications to obtain optimal power extraction.Hence,a novel and metaheuristic technique,named enhanced atom search optimization(EASO),is designed for a permanent magnet synchronous generator(PMSG)based WECS,which can be employed to track the maximum power point.One of the most promising benefits of this technique is powerful global search capability that leads to fast response and high-quality optimal solution.Besides,in contrast with other conventional meta-heuristic techniques,EASO is extremely not relying on the original solution,which can avoid sinking into a low-quality local maximum power point(LMPP)by realizing an appropriate trade-off between global exploration and local exploitation.At last,simulations employing two case studies through Matlab/Simulink validate the practicability and effectiveness of the proposed techniques for optimal proportional-integral-derivative(PID)control parameters tuning of PMSG based WECS under a variety of wind conditions.
文摘针对爬山法(hill-climbing searching,HCS)在最大功率点(maximum power point,MPP)处存在的转速振荡和风速变化导致搜索方向误判的问题,提出1种具有扰动停止机制的改进爬山算法。该算法不仅继承了变步长爬山法快速搜索至MPP附近的优点,还具有MPP检测和停止机制。在风机跟踪至MPP附近时,该机制不仅可以有效降低转速振荡对风机系统机械部件的磨损,而且克服了算法停止机制生效后风速再次变化时对搜索方向判断的干扰,从而进一步提高了风能捕获效率。在简化风电系统模型的基础上,仿真结果验证了该算法的有效性和优越性。
