In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected, and critical control poin...In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected, and critical control points in the progress of hog slaughter and processing were analyzed. The results showed that microbial con- taminatian existed in the entire slaughter and processing progress, including shower and assassination bloodletting, separation of the internal organs, chopping boards, workshop environment, personal hygiene of the operators, etc. , which should be paid more attention to. The results indicated that reasonable protection measures should be carried out, disinfection awareness of the operators should be improved, and regular disinfection should be ruled under the condition of continu- ous operation.展开更多
The control points are the key issue of the internal control, and the key control points mean the control joints that play an important part in the process of the operation. If these key control points are not well co...The control points are the key issue of the internal control, and the key control points mean the control joints that play an important part in the process of the operation. If these key control points are not well controlled, the process of the operation disposal will be mistaken and cannot reach the goal. However, for the confirmation of the control points, many studies only do qualitative research from the important aspect instead of quantificational research. They are devoid of a series of scientific methods. This paper advances quantificational methods to confirm the key control points from two aspects of job evaluation and mathematics model.展开更多
China's land area is relatively vast, but there are obvious differences in geological structure and environmental conditions in various regions, which lead to the situation of crossing mountains in the process of ...China's land area is relatively vast, but there are obvious differences in geological structure and environmental conditions in various regions, which lead to the situation of crossing mountains in the process of highway construction. When encountering this problem, tunnel engineering can be used to carry out highway construction. This article focuses on the highway tunnel construction technology and control points to conduct a comprehensive and in-depth research and analysis, hoping to help the future sustainable and stable development of China's highway engineering industry and lay a solid foundation for the continuous development of China's comprehensive national strength.展开更多
With the effective implementation of construction engineering management work, in order to comprehensively promote the construction level of construction engineering, optimize the quality of construction management, c...With the effective implementation of construction engineering management work, in order to comprehensively promote the construction level of construction engineering, optimize the quality of construction management, construction engineering management personnel in the existing engineering technology requirements, clear the management points and work core tasks, build new optimization measures, put forward new working ideas for the later construction engineering technology management work. However, at the present stage, due to the restriction of the management mode and work mode, most of the construction engineering technology management work in China is not implemented in place, and the various management work objectives are not clear, which not only leads to the difficult implementation of various management tasks, but also leads to the occurrence of various safety risks. For this paper on the current stage of the basis of the analysis of the importance of construction engineering technical management, clear the main problems existing in the work, the construction engineering technical management control points and optimization measures, on the one hand to promote the high quality construction of construction engineering, on the other hand for the late construction engineering quality optimization provides new ideas.展开更多
Objective: to explore and analyze the quality management of key control points in blood supply department of blood station. Methods: the study took the blood supply department of the blood station as the pilot, and th...Objective: to explore and analyze the quality management of key control points in blood supply department of blood station. Methods: the study took the blood supply department of the blood station as the pilot, and the research was carried out from April 2021 to may 2022. The observation group was divided according to the time. From April 2021 to October 2021, 500 blood samples were screened through retrospective analysis, aiming at the key control points in the storage and distribution of blood products in the quality management of the blood supply department of the blood station, forming a clear quality management system within the blood supply department, and strengthening the quality management of key control points. The qualified rate of blood quality was observed from November 2021 to February 2025. Results: the unqualified rate of blood after quality management of key control points was lower than that before management (P < 0.05);Before and after the quality management of key control points, the management quality scores of blood supply department staff in environmental monitoring, quality screening and safety management were higher than those before the management (P < 0.05). Conclusion: strengthening the quality management of the key control points of the blood supply department of the blood station and implementing the continuous quality improvement countermeasures are helpful to strengthen the quality management system of the blood supply department, implement the work of the key control points of the blood supply department of the blood station, improve the quality control in the storage and distribution of blood products, effectively ensure the blood quality, and can be popularized in practical work.展开更多
Under the impetus of building a socialist road, the construction industry is developing rapidly, both in scale and in quantity. However, in the actual construction process, there will still be many problems, which wil...Under the impetus of building a socialist road, the construction industry is developing rapidly, both in scale and in quantity. However, in the actual construction process, there will still be many problems, which will affect the construction progress and quality. Among them, the over-budget phenomenon of project cost caused by various factors is still relatively serious. Therefore, it is necessary to fully clarify the key points of budget control in the process of cost budget, so as to make the cost budget more scientific and accurate, thus achieving the purpose of cost control and reducing economic losses.展开更多
The budget management of construction project cost is the premise and foundation of construction project management. Good cost budget management can effectively improve the quality standard in the process of construct...The budget management of construction project cost is the premise and foundation of construction project management. Good cost budget management can effectively improve the quality standard in the process of construction, and lay a solid foundation for the later construction quality acceptance. Nowadays, more and more developers and construction units pay more attention to the cost budget management, and are building a professional team. The purpose is to improve their own cost budget management ability and reduce the economic loss in the construction process.展开更多
Nowadays, with the rapid development of market economy, the importance of construction cost budget is becoming more and more obvious. Based on this premise, it has received extensive attention from various enterprises...Nowadays, with the rapid development of market economy, the importance of construction cost budget is becoming more and more obvious. Based on this premise, it has received extensive attention from various enterprises. In the development of the industry, it is necessary to strengthen the management of project cost budget and other related work and analyze the projects exceeding the budget timely, control the project cost budget from every aspect of the specific work and from various angles strictly, and timely and accurately grasp the project cost budget. This paper focuses on the key points of construction project cost budget control and its grasp, hoping to help promote the development of the construction industry.展开更多
With the acceleration of urbanization, a large number of new-type buildings appear constantly, and building construction has become a normal activity in every city. The process of building construction is a complex an...With the acceleration of urbanization, a large number of new-type buildings appear constantly, and building construction has become a normal activity in every city. The process of building construction is a complex and important process, which directly relates to the quality of the project and the service life of the project. There is a close connection between the various construction links of the building, and once there is a problem in a certain link, it may cause extremely serious consequences. So, as an important construction link, concrete pouring is very important to do a good job in construction and supervision.展开更多
With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction ...With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction quality control are of great significance to enhance the competitiveness of construction enterprises and realize sustainable development.In this paper,the effective strategy of construction management and the effective strategy of construction quality control will be discussed in depth,aiming at providing useful management and quality control strategies for construction enterprises.展开更多
Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the ti...Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the time? varying deadzone and gain. Methods The large positioning errors caused by the time varying deadzone were significantly reduced by using the dynamic compensation method for the deadzone; and the large overshoot caused by the time varying gain were dramatically reduced by using the three section intelligent control schemes. Results Experimental results demonstrated that the positioning performance of rapid response, high accuracy and smaller or even no overshoot was achieved under a wide variations of load torque. Conclusion The good positioning performance for valve controlled motor servo systems has been achieved in the presence of the time varying deadzone and gain.展开更多
We present the best bounds on the distance between 3-direction quartic box spline surface patch and its control net by means of analysis and computing for the basis functions of 3-direction quartic box spline surface....We present the best bounds on the distance between 3-direction quartic box spline surface patch and its control net by means of analysis and computing for the basis functions of 3-direction quartic box spline surface.Both the local bounds and the global bounds are given by the maximum norm of the first differences or second differences or mixed differences of the control points of the surface patch.展开更多
The scale-invariant feature transform(SIFT)ability to automatic control points(CPs)extraction is very well known on remote sensing images,however,its result inaccurate and sometimes has incorrect matching from generat...The scale-invariant feature transform(SIFT)ability to automatic control points(CPs)extraction is very well known on remote sensing images,however,its result inaccurate and sometimes has incorrect matching from generating a small number of false CPs pairs,their matching has high false alarm.This paper presents a method containing a modification to improve the performance of the SIFT CPs matching by applying sum of absolute difference(SAD)in different manner for the new optical satellite generation called near-equatorial orbit satellite(NEqO)and multi-sensor images.The proposed method leads to improving CPs matching with a significantly higher rate of correct matches.The data in this study were obtained from the RazakSAT satellite covering the Kuala Lumpur-Pekan area.The proposed method consists of three parts:(1)applying the SIFT to extract CPs automatically,(2)refining CPs matching by SAD algorithm with empirical threshold,and(3)evaluating the refined CPs scenario by comparing the result of the original SIFT with that of the proposed method.The result indicates an accurate and precise performance of the model,which showed the effectiveness and robustness of the proposed approach.展开更多
A neural network model with a special structure, which is divided into linearand nonlinear parts, was proposed for identification of a nonlinear system. In this model, thenonlinear part of the object is treated as a m...A neural network model with a special structure, which is divided into linearand nonlinear parts, was proposed for identification of a nonlinear system. In this model, thenonlinear part of the object is treated as a measured disturbance, and is compensated by a feedforward method; an adaptive pole placement algorithm is used to control the linear part of theobject. The simulation results show that the identification efficiency and accuracy are improvedwhen the new controller is applied to sintering finish point control.展开更多
Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model referen...Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model reference adaptive controller is designed using equilibrium point stability theory and output error equation polynomial. The reference model is selected in such a way that it meets the system dynamic performance. Hardware configuration of asymmetric cylinder controlled by asymmetric valve hydraulic system is replaced by intelligent control algorithm, thus the cost is lowered and easy to application. Simulation results demonstrate that the proposed adaptive control sheme has good adaptive ability and well solves asymmetric dynamic performance problem. The designed adaptive controller is fairly robust to load disturbance and system parameter variation.展开更多
For the advanced tokamak,the particle deposition and thermal load on the divertor is a big challenge.By moving the strike points on divertor target plates,the position of particle deposition and thermal load can be sh...For the advanced tokamak,the particle deposition and thermal load on the divertor is a big challenge.By moving the strike points on divertor target plates,the position of particle deposition and thermal load can be shifted.We could adjust the Poloidal Field(PF) coil current to achieve the strike point position feedback control.Using isoflux control method,the strike point position can be controlled by controlling the X point position.On the basis of experimental data,we establish relational expressions between X point position and strike point position.Benchmark experiments are carried out to validate the correctness and robustness of the control methods.The strike point position is successfully controlled following our command in the EAST operation.展开更多
A program control was applied in the fuel gas shuttle kiln,and its principle and disadvantge were analyzed.An advanced set point control method,in which the change rate of temperature is the controlled variable,is als...A program control was applied in the fuel gas shuttle kiln,and its principle and disadvantge were analyzed.An advanced set point control method,in which the change rate of temperature is the controlled variable,is also described,and the new control system makes the control precision of temperature improved.展开更多
This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 inn...This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was proposed.Second,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was proposed.Third,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was proposed.Fourth,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the rectenna.Fifth,a high-efficiency heat radiator design method based on bionics and topology optimization was proposed.Sixth,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is presented.Seventh,high-precision measurement technology for high-accuracy beam-pointing control was developed.Eighth,a smart mechanical structure was designed and developed.Finally,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained.展开更多
The optimal torque(OT)method,which is preferred for its simplicity,is widely employed in maximum power point tracking(MPPT)control strategies for wind energy capture in wind turbine generators(WTGs).Based on the OT me...The optimal torque(OT)method,which is preferred for its simplicity,is widely employed in maximum power point tracking(MPPT)control strategies for wind energy capture in wind turbine generators(WTGs).Based on the OT method,the decreased torque gain(DTG)method is developed to improve turbine acceleration through a reduction of the torque gain coefficient.However,the DTG method does not fully align with the acceleration performance required by wind turbines,which subsequently limits improvements in wind energy capture efficiency.To address these concerns,a novel MPPT control strategy is proposed,which introduces redefined torque curve and torque command conceptualized based on a higher-order function relative to rotor speed.Additionally,an adaptive algorithm for the periodic update of the torque command is suggested to better accommodate the variability of turbulent wind speeds,thus aiming to improve the wind energy capture efficiency.The effectiveness of the proposed MPPT control strategy is substantiated through the wind turbine simulator(WTS)-based experiments.展开更多
Data warehouse (DW), a new technology invented in 1990s, is more useful for integrating and analyzing massive data than traditional database. Its application in geology field can be divided into 3 phrases: 1992-1996,...Data warehouse (DW), a new technology invented in 1990s, is more useful for integrating and analyzing massive data than traditional database. Its application in geology field can be divided into 3 phrases: 1992-1996, commercial data warehouse (CDW) appeared; 1996-1999, geological data warehouse (GDW) appeared and the geologists or geographers realized the importance of DW and began the studies on it, but the practical DW still followed the framework of DB; 2000 to present, geological data warehouse grows, and the theory of geo-spatial data warehouse (GSDW) has been developed but the research in geological area is still deficient except that in geography. Although some developments of GDW have been made, its core still follows the CDW-organizing data by time and brings about 3 problems: difficult to integrate the geological data, for the data feature more space than time; hard to store the massive data in different levels due to the same reason; hardly support the spatial analysis if the data are organized by time as CDW does. So the GDW should be redesigned by organizing data by scale in order to store mass data in different levels and synthesize the data in different granularities, and choosing space control points to replace the former time control points so as to integrate different types of data by the method of storing one type data as one layer and then to superpose the layers. In addition, data cube, a wide used technology in CDW, will be no use in GDW, for the causality among the geological data is not so obvious as commercial data, as the data are the mixed result of many complex rules, and their analysis always needs the special geological methods and software; on the other hand, data cube for mass and complex geo-data will devour too much store space to be practical. On this point, the main purpose of GDW may be fit for data integration unlike CDW for data analysis.展开更多
文摘In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected, and critical control points in the progress of hog slaughter and processing were analyzed. The results showed that microbial con- taminatian existed in the entire slaughter and processing progress, including shower and assassination bloodletting, separation of the internal organs, chopping boards, workshop environment, personal hygiene of the operators, etc. , which should be paid more attention to. The results indicated that reasonable protection measures should be carried out, disinfection awareness of the operators should be improved, and regular disinfection should be ruled under the condition of continu- ous operation.
文摘The control points are the key issue of the internal control, and the key control points mean the control joints that play an important part in the process of the operation. If these key control points are not well controlled, the process of the operation disposal will be mistaken and cannot reach the goal. However, for the confirmation of the control points, many studies only do qualitative research from the important aspect instead of quantificational research. They are devoid of a series of scientific methods. This paper advances quantificational methods to confirm the key control points from two aspects of job evaluation and mathematics model.
文摘China's land area is relatively vast, but there are obvious differences in geological structure and environmental conditions in various regions, which lead to the situation of crossing mountains in the process of highway construction. When encountering this problem, tunnel engineering can be used to carry out highway construction. This article focuses on the highway tunnel construction technology and control points to conduct a comprehensive and in-depth research and analysis, hoping to help the future sustainable and stable development of China's highway engineering industry and lay a solid foundation for the continuous development of China's comprehensive national strength.
文摘With the effective implementation of construction engineering management work, in order to comprehensively promote the construction level of construction engineering, optimize the quality of construction management, construction engineering management personnel in the existing engineering technology requirements, clear the management points and work core tasks, build new optimization measures, put forward new working ideas for the later construction engineering technology management work. However, at the present stage, due to the restriction of the management mode and work mode, most of the construction engineering technology management work in China is not implemented in place, and the various management work objectives are not clear, which not only leads to the difficult implementation of various management tasks, but also leads to the occurrence of various safety risks. For this paper on the current stage of the basis of the analysis of the importance of construction engineering technical management, clear the main problems existing in the work, the construction engineering technical management control points and optimization measures, on the one hand to promote the high quality construction of construction engineering, on the other hand for the late construction engineering quality optimization provides new ideas.
文摘Objective: to explore and analyze the quality management of key control points in blood supply department of blood station. Methods: the study took the blood supply department of the blood station as the pilot, and the research was carried out from April 2021 to may 2022. The observation group was divided according to the time. From April 2021 to October 2021, 500 blood samples were screened through retrospective analysis, aiming at the key control points in the storage and distribution of blood products in the quality management of the blood supply department of the blood station, forming a clear quality management system within the blood supply department, and strengthening the quality management of key control points. The qualified rate of blood quality was observed from November 2021 to February 2025. Results: the unqualified rate of blood after quality management of key control points was lower than that before management (P < 0.05);Before and after the quality management of key control points, the management quality scores of blood supply department staff in environmental monitoring, quality screening and safety management were higher than those before the management (P < 0.05). Conclusion: strengthening the quality management of the key control points of the blood supply department of the blood station and implementing the continuous quality improvement countermeasures are helpful to strengthen the quality management system of the blood supply department, implement the work of the key control points of the blood supply department of the blood station, improve the quality control in the storage and distribution of blood products, effectively ensure the blood quality, and can be popularized in practical work.
文摘Under the impetus of building a socialist road, the construction industry is developing rapidly, both in scale and in quantity. However, in the actual construction process, there will still be many problems, which will affect the construction progress and quality. Among them, the over-budget phenomenon of project cost caused by various factors is still relatively serious. Therefore, it is necessary to fully clarify the key points of budget control in the process of cost budget, so as to make the cost budget more scientific and accurate, thus achieving the purpose of cost control and reducing economic losses.
文摘The budget management of construction project cost is the premise and foundation of construction project management. Good cost budget management can effectively improve the quality standard in the process of construction, and lay a solid foundation for the later construction quality acceptance. Nowadays, more and more developers and construction units pay more attention to the cost budget management, and are building a professional team. The purpose is to improve their own cost budget management ability and reduce the economic loss in the construction process.
文摘Nowadays, with the rapid development of market economy, the importance of construction cost budget is becoming more and more obvious. Based on this premise, it has received extensive attention from various enterprises. In the development of the industry, it is necessary to strengthen the management of project cost budget and other related work and analyze the projects exceeding the budget timely, control the project cost budget from every aspect of the specific work and from various angles strictly, and timely and accurately grasp the project cost budget. This paper focuses on the key points of construction project cost budget control and its grasp, hoping to help promote the development of the construction industry.
文摘With the acceleration of urbanization, a large number of new-type buildings appear constantly, and building construction has become a normal activity in every city. The process of building construction is a complex and important process, which directly relates to the quality of the project and the service life of the project. There is a close connection between the various construction links of the building, and once there is a problem in a certain link, it may cause extremely serious consequences. So, as an important construction link, concrete pouring is very important to do a good job in construction and supervision.
文摘With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction quality control are of great significance to enhance the competitiveness of construction enterprises and realize sustainable development.In this paper,the effective strategy of construction management and the effective strategy of construction quality control will be discussed in depth,aiming at providing useful management and quality control strategies for construction enterprises.
文摘Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the time? varying deadzone and gain. Methods The large positioning errors caused by the time varying deadzone were significantly reduced by using the dynamic compensation method for the deadzone; and the large overshoot caused by the time varying gain were dramatically reduced by using the three section intelligent control schemes. Results Experimental results demonstrated that the positioning performance of rapid response, high accuracy and smaller or even no overshoot was achieved under a wide variations of load torque. Conclusion The good positioning performance for valve controlled motor servo systems has been achieved in the presence of the time varying deadzone and gain.
基金Supported by the National Natural Science Foundation of China (61170324 and 61100105)
文摘We present the best bounds on the distance between 3-direction quartic box spline surface patch and its control net by means of analysis and computing for the basis functions of 3-direction quartic box spline surface.Both the local bounds and the global bounds are given by the maximum norm of the first differences or second differences or mixed differences of the control points of the surface patch.
文摘The scale-invariant feature transform(SIFT)ability to automatic control points(CPs)extraction is very well known on remote sensing images,however,its result inaccurate and sometimes has incorrect matching from generating a small number of false CPs pairs,their matching has high false alarm.This paper presents a method containing a modification to improve the performance of the SIFT CPs matching by applying sum of absolute difference(SAD)in different manner for the new optical satellite generation called near-equatorial orbit satellite(NEqO)and multi-sensor images.The proposed method leads to improving CPs matching with a significantly higher rate of correct matches.The data in this study were obtained from the RazakSAT satellite covering the Kuala Lumpur-Pekan area.The proposed method consists of three parts:(1)applying the SIFT to extract CPs automatically,(2)refining CPs matching by SAD algorithm with empirical threshold,and(3)evaluating the refined CPs scenario by comparing the result of the original SIFT with that of the proposed method.The result indicates an accurate and precise performance of the model,which showed the effectiveness and robustness of the proposed approach.
文摘A neural network model with a special structure, which is divided into linearand nonlinear parts, was proposed for identification of a nonlinear system. In this model, thenonlinear part of the object is treated as a measured disturbance, and is compensated by a feedforward method; an adaptive pole placement algorithm is used to control the linear part of theobject. The simulation results show that the identification efficiency and accuracy are improvedwhen the new controller is applied to sintering finish point control.
文摘Partial pressure, system vibration and asymmetric system dynamic performance exit in asymmetric cylinder controller by symmetric valve hydraulic system. To solve this problem in the force control system, model reference adaptive controller is designed using equilibrium point stability theory and output error equation polynomial. The reference model is selected in such a way that it meets the system dynamic performance. Hardware configuration of asymmetric cylinder controlled by asymmetric valve hydraulic system is replaced by intelligent control algorithm, thus the cost is lowered and easy to application. Simulation results demonstrate that the proposed adaptive control sheme has good adaptive ability and well solves asymmetric dynamic performance problem. The designed adaptive controller is fairly robust to load disturbance and system parameter variation.
基金supported by the National Magnetic Confinement Fusion Science Program of China(Nos.2012GB105000 and 2014GB103000)
文摘For the advanced tokamak,the particle deposition and thermal load on the divertor is a big challenge.By moving the strike points on divertor target plates,the position of particle deposition and thermal load can be shifted.We could adjust the Poloidal Field(PF) coil current to achieve the strike point position feedback control.Using isoflux control method,the strike point position can be controlled by controlling the X point position.On the basis of experimental data,we establish relational expressions between X point position and strike point position.Benchmark experiments are carried out to validate the correctness and robustness of the control methods.The strike point position is successfully controlled following our command in the EAST operation.
文摘A program control was applied in the fuel gas shuttle kiln,and its principle and disadvantge were analyzed.An advanced set point control method,in which the change rate of temperature is the controlled variable,is also described,and the new control system makes the control precision of temperature improved.
文摘This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was proposed.Second,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was proposed.Third,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was proposed.Fourth,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the rectenna.Fifth,a high-efficiency heat radiator design method based on bionics and topology optimization was proposed.Sixth,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is presented.Seventh,high-precision measurement technology for high-accuracy beam-pointing control was developed.Eighth,a smart mechanical structure was designed and developed.Finally,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained.
基金supported in part by the National Key R&D Program of China(No.2021YFB1506904)the National Natural Science Foundation of China(No.51977111).
文摘The optimal torque(OT)method,which is preferred for its simplicity,is widely employed in maximum power point tracking(MPPT)control strategies for wind energy capture in wind turbine generators(WTGs).Based on the OT method,the decreased torque gain(DTG)method is developed to improve turbine acceleration through a reduction of the torque gain coefficient.However,the DTG method does not fully align with the acceleration performance required by wind turbines,which subsequently limits improvements in wind energy capture efficiency.To address these concerns,a novel MPPT control strategy is proposed,which introduces redefined torque curve and torque command conceptualized based on a higher-order function relative to rotor speed.Additionally,an adaptive algorithm for the periodic update of the torque command is suggested to better accommodate the variability of turbulent wind speeds,thus aiming to improve the wind energy capture efficiency.The effectiveness of the proposed MPPT control strategy is substantiated through the wind turbine simulator(WTS)-based experiments.
文摘Data warehouse (DW), a new technology invented in 1990s, is more useful for integrating and analyzing massive data than traditional database. Its application in geology field can be divided into 3 phrases: 1992-1996, commercial data warehouse (CDW) appeared; 1996-1999, geological data warehouse (GDW) appeared and the geologists or geographers realized the importance of DW and began the studies on it, but the practical DW still followed the framework of DB; 2000 to present, geological data warehouse grows, and the theory of geo-spatial data warehouse (GSDW) has been developed but the research in geological area is still deficient except that in geography. Although some developments of GDW have been made, its core still follows the CDW-organizing data by time and brings about 3 problems: difficult to integrate the geological data, for the data feature more space than time; hard to store the massive data in different levels due to the same reason; hardly support the spatial analysis if the data are organized by time as CDW does. So the GDW should be redesigned by organizing data by scale in order to store mass data in different levels and synthesize the data in different granularities, and choosing space control points to replace the former time control points so as to integrate different types of data by the method of storing one type data as one layer and then to superpose the layers. In addition, data cube, a wide used technology in CDW, will be no use in GDW, for the causality among the geological data is not so obvious as commercial data, as the data are the mixed result of many complex rules, and their analysis always needs the special geological methods and software; on the other hand, data cube for mass and complex geo-data will devour too much store space to be practical. On this point, the main purpose of GDW may be fit for data integration unlike CDW for data analysis.