Because of the randomness of wind power and photovoltaic(PV)output of new energy bases,the problem of peak regulation capability and voltage stability of ultra-high voltage direct current(UHVDC)transmission lines,we p...Because of the randomness of wind power and photovoltaic(PV)output of new energy bases,the problem of peak regulation capability and voltage stability of ultra-high voltage direct current(UHVDC)transmission lines,we proposed an optimum allocation method of installed capacity of the solar-thermal power station based on chance constrained programming in this work.Firstly,we established the uncertainty model of wind power and PV based on the chance constrained planning theory.Then we used the K-medoids clusteringmethod to cluster the scenarios considering the actual operation scenarios throughout the year.Secondly,we established the optimal configuration model based on the objective function of the strongest transient voltage stability and the lowest overall cost of operation.Finally,by quantitative analysis of actual wind power and photovoltaic new energy base,this work verified the feasibility of the proposed method.As a result of the simulations,we found that using the optimal configuration method of solar-thermal power stations could ensure an accurate allocation of installed capacity.When the installed capacity of the solar-thermal power station is 1×106 kW,the transient voltage recovery index(TVRI)is 0.359,which has a strong voltage support capacity for the system.Based on the results of this work,the optimal configuration of the installed capacity of the solar-thermal power plant can improve peak shaving performance,transient voltage support capability,and new energy consumption while satisfying the Direct Current(DC)outgoing transmission premise.展开更多
Selecting a cost optimum subset of discrete-value dispersion compensation modules (DV-DCMs) subject to maximum module count from an available set of DV-DCMs is a NP-hard problem. We derive a novel dynamic programming ...Selecting a cost optimum subset of discrete-value dispersion compensation modules (DV-DCMs) subject to maximum module count from an available set of DV-DCMs is a NP-hard problem. We derive a novel dynamic programming algorithm with pseudo-polynomial time bound and show that DV-DCM cost re-scaling can improve the running time.展开更多
When a pig mounted with permanent magnets gets stuck in the pipeline,it can be located by detecting the magnetic anomalies on the ground using a single-axis magnetic sensor.In order to collect the magnetic anomaly eff...When a pig mounted with permanent magnets gets stuck in the pipeline,it can be located by detecting the magnetic anomalies on the ground using a single-axis magnetic sensor.In order to collect the magnetic anomaly efficiently through single-axis magnetic sensor,a geometric detection model and calculation method for singleaxis magnetic anomaly detection is established in this paper.The distribution of magnetic inclination and declination of the measuring points is obtained.The results indicate that the magnetic inclination of all measuring points vary within a small range of 2°,and this value is highly dependent on the magnetic sensor which is configured aboveground around the geomagnetic inclination.However,the magnetic declination at different points of detection surface is subject to the geomagnetic components and the Y-axis component of the magnetic field of magnets.The magnetic declinations distribute irregularly and vary in a wide range.Therefore,to achieve a high-efficiency detection with the single-axis sensor,the sensor shall be placed in such a manner that the magnetic inclination thereof coincides with the geomagnetic inclination.The magnetic declination of the sensor can be calculated using s,the superposed Y-axis component induced by the permanent magnets,and the corresponding formula given in this paper.The article demonstrates the feasibility of locating a blocked pig in the pipeline based on the single-axis magnetic anomaly detection.It will have a practical significance in guiding the engineering detection.展开更多
Optims S.A. (Evry, France), the leading global provider of Revenue Management Systems (RMS) and IT enabling solutions dedicated to the hospitality, tourism and transport industries is pleased to announce the implement...Optims S.A. (Evry, France), the leading global provider of Revenue Management Systems (RMS) and IT enabling solutions dedicated to the hospitality, tourism and transport industries is pleased to announce the implementation of an Optims.Hotel Revenue Management System in the Royal Windsor Hotel, Brussels, a Warwick International Hotel and a member of Leading Hotels of the World.展开更多
基金funded by Major Science and Technology Projects in Gansu Province(19ZD2GA003).
文摘Because of the randomness of wind power and photovoltaic(PV)output of new energy bases,the problem of peak regulation capability and voltage stability of ultra-high voltage direct current(UHVDC)transmission lines,we proposed an optimum allocation method of installed capacity of the solar-thermal power station based on chance constrained programming in this work.Firstly,we established the uncertainty model of wind power and PV based on the chance constrained planning theory.Then we used the K-medoids clusteringmethod to cluster the scenarios considering the actual operation scenarios throughout the year.Secondly,we established the optimal configuration model based on the objective function of the strongest transient voltage stability and the lowest overall cost of operation.Finally,by quantitative analysis of actual wind power and photovoltaic new energy base,this work verified the feasibility of the proposed method.As a result of the simulations,we found that using the optimal configuration method of solar-thermal power stations could ensure an accurate allocation of installed capacity.When the installed capacity of the solar-thermal power station is 1×106 kW,the transient voltage recovery index(TVRI)is 0.359,which has a strong voltage support capacity for the system.Based on the results of this work,the optimal configuration of the installed capacity of the solar-thermal power plant can improve peak shaving performance,transient voltage support capability,and new energy consumption while satisfying the Direct Current(DC)outgoing transmission premise.
文摘Selecting a cost optimum subset of discrete-value dispersion compensation modules (DV-DCMs) subject to maximum module count from an available set of DV-DCMs is a NP-hard problem. We derive a novel dynamic programming algorithm with pseudo-polynomial time bound and show that DV-DCM cost re-scaling can improve the running time.
基金This work is supported by the National Natural Science Foundation of China under Grant No.41374151the Sichuan Province Applied Basic Research Project(No.2017JY0162)the Young Scholars Development Fund of SWPU(No.201599010079).
文摘When a pig mounted with permanent magnets gets stuck in the pipeline,it can be located by detecting the magnetic anomalies on the ground using a single-axis magnetic sensor.In order to collect the magnetic anomaly efficiently through single-axis magnetic sensor,a geometric detection model and calculation method for singleaxis magnetic anomaly detection is established in this paper.The distribution of magnetic inclination and declination of the measuring points is obtained.The results indicate that the magnetic inclination of all measuring points vary within a small range of 2°,and this value is highly dependent on the magnetic sensor which is configured aboveground around the geomagnetic inclination.However,the magnetic declination at different points of detection surface is subject to the geomagnetic components and the Y-axis component of the magnetic field of magnets.The magnetic declinations distribute irregularly and vary in a wide range.Therefore,to achieve a high-efficiency detection with the single-axis sensor,the sensor shall be placed in such a manner that the magnetic inclination thereof coincides with the geomagnetic inclination.The magnetic declination of the sensor can be calculated using s,the superposed Y-axis component induced by the permanent magnets,and the corresponding formula given in this paper.The article demonstrates the feasibility of locating a blocked pig in the pipeline based on the single-axis magnetic anomaly detection.It will have a practical significance in guiding the engineering detection.
文摘Optims S.A. (Evry, France), the leading global provider of Revenue Management Systems (RMS) and IT enabling solutions dedicated to the hospitality, tourism and transport industries is pleased to announce the implementation of an Optims.Hotel Revenue Management System in the Royal Windsor Hotel, Brussels, a Warwick International Hotel and a member of Leading Hotels of the World.