Propose the sequential circuits with the ternary D-ffs in series^1. Discuss the equivalence between the sequential circuits with the p-valued flip-flops in series and in parallel as a part of studying the multiple val...Propose the sequential circuits with the ternary D-ffs in series^1. Discuss the equivalence between the sequential circuits with the p-valued flip-flops in series and in parallel as a part of studying the multiple valued logic circuits.展开更多
This paper discusses a high efficient parallel circuit simulator for iterative power grid optimization. The simulator is implemented by FPGA. We focus particularly on the following points: 1) Selection of the analysis...This paper discusses a high efficient parallel circuit simulator for iterative power grid optimization. The simulator is implemented by FPGA. We focus particularly on the following points: 1) Selection of the analysis method for power grid optimization, the proposed simulator introduces hardware-oriented fixed point arithmetic instead of floating point arithmetic. It accomplishes the high accuracy by selecting appropriate time step of the simulation;2) The simulator achieves high speed simulation by developing dedicated hardware and adopting parallel processing. Experiments prove that the proposed simulator using 80 MHz FPGA and eight parallel processing achieves 35 times faster simulation than software processing with 2.8 GHz CPU while maintaining almost same accuracy in comparison with SPICE simulation.展开更多
在激光无线能量传输中,由于瞄准系统误差和物体遮挡的影响,光电池阵列接收到的激光辐照分布不均匀,导致光电池阵列组串内的电池间出现电流失配,输出功率下降。针对该问题,采用分布式最大功率点追踪(Distributed Maximum Power Point Tra...在激光无线能量传输中,由于瞄准系统误差和物体遮挡的影响,光电池阵列接收到的激光辐照分布不均匀,导致光电池阵列组串内的电池间出现电流失配,输出功率下降。针对该问题,采用分布式最大功率点追踪(Distributed Maximum Power Point Tracking,DMPPT)技术,减少光电池阵列组串内的电池间电流失配,并用并联型Boost(PT-Boost)电路替代传统Boost电路,降低DC/DC转换器的输入电流纹波,使DMPPT系统获得高追踪效率。实验结果表明,相较于传统Boost电路,PT-Boost电路的追踪效率提高3.6%,达到93.5%。在上述研究的基础上,设置了遮光率分别为0%、25%和50%的激光无线能量传输场景,DMPPT系统整体效率分别达到了93%、92.6%和90.3%。该研究结果对激光辐照不均匀场景下激光无线能量传输的最大功率点追踪指导意义。展开更多
直流系统是支撑高比例新能源接入与灵活高效用能的重要技术方向。固态式直流断路器(solid state DC circuit breaker,SSCB)具有开断速度极快、无电弧、寿命长等优点,在中低压直流系统的故障保护中得到广泛应用。随着电力电子器件的发展...直流系统是支撑高比例新能源接入与灵活高效用能的重要技术方向。固态式直流断路器(solid state DC circuit breaker,SSCB)具有开断速度极快、无电弧、寿命长等优点,在中低压直流系统的故障保护中得到广泛应用。随着电力电子器件的发展,固态式直流断路器的拓扑结构、工作性能也在不断进步。为此基于逆阻型集成门极换流晶闸管(intergated gate commutate thyristor,IGCT),提出了一种新型的固态式直流断路器结构及设计方法,通流支路采用逆阻IGCT反并联结构实现双向通流,缓冲支路采用金属氧化物避雷器(metal oxide varistor,MOV)-电容结构来抑制过电压,吸能支路采用MOV吸收系统能量。进一步地,给出了关键元器件的参数设计方法,并验证了有效性;设计了性能良好的重力热管散热器,单个模块散热功率可达700 W;提出了主被动结合的控保策略,提高断路器的保护性能。最后,研制了固态式直流断路器样机,可用于750 V以内的低压直流系统,额定通流可达2 kA,可在百微秒内开断10 kA故障电流,成本低、体积小、高可靠,具有良好的应用前景。展开更多
Although neural methods have been comprehensively applied in different fields,symbolic based logic reasoning is still the main choice for numerous applications based on knowledge graphs.To enhance the efficiency of kn...Although neural methods have been comprehensively applied in different fields,symbolic based logic reasoning is still the main choice for numerous applications based on knowledge graphs.To enhance the efficiency of knowledge graph reasoning,researchers studied how to design parallelalgorithms for reasoning,and take advantage of high-performance architectures,like neural networks.Although parallel algorithms and architectures improve the performance of reasoning to some degree,the task of reasoning is essentially bounded by its computational complexity,i.e.,the PTiMe-Completeness or higher complexities.This means that the task of reasoning is not parallelly tractable.In this work,we investigate the parallel tractability of knowledge graph reasoning from the perspective of parallel complexity.We concentrate on knowledge graphs that are Datalog rewritable.We aim to capture the parallelly tractable classes of knowledge graphs,for which,the task of reasoning falls in the NC complexity.To this end,we employ the computational model of Boolean circuit to formalize knowledge graph reasoning and further obtain all the theoretical results.We then use the results to analyze DHL(Description Horn Logic),a fragment of description logic.We give the properties that ensure the parallel tractability of DHL reasoning.One can utilize our results to check the parallel tractability of real knowledge graphs.In addition,the Boolean circuits proposed in this paper can also be used to construct neural networks to perform knowledge graph reasoning.展开更多
文摘Propose the sequential circuits with the ternary D-ffs in series^1. Discuss the equivalence between the sequential circuits with the p-valued flip-flops in series and in parallel as a part of studying the multiple valued logic circuits.
文摘This paper discusses a high efficient parallel circuit simulator for iterative power grid optimization. The simulator is implemented by FPGA. We focus particularly on the following points: 1) Selection of the analysis method for power grid optimization, the proposed simulator introduces hardware-oriented fixed point arithmetic instead of floating point arithmetic. It accomplishes the high accuracy by selecting appropriate time step of the simulation;2) The simulator achieves high speed simulation by developing dedicated hardware and adopting parallel processing. Experiments prove that the proposed simulator using 80 MHz FPGA and eight parallel processing achieves 35 times faster simulation than software processing with 2.8 GHz CPU while maintaining almost same accuracy in comparison with SPICE simulation.
文摘在激光无线能量传输中,由于瞄准系统误差和物体遮挡的影响,光电池阵列接收到的激光辐照分布不均匀,导致光电池阵列组串内的电池间出现电流失配,输出功率下降。针对该问题,采用分布式最大功率点追踪(Distributed Maximum Power Point Tracking,DMPPT)技术,减少光电池阵列组串内的电池间电流失配,并用并联型Boost(PT-Boost)电路替代传统Boost电路,降低DC/DC转换器的输入电流纹波,使DMPPT系统获得高追踪效率。实验结果表明,相较于传统Boost电路,PT-Boost电路的追踪效率提高3.6%,达到93.5%。在上述研究的基础上,设置了遮光率分别为0%、25%和50%的激光无线能量传输场景,DMPPT系统整体效率分别达到了93%、92.6%和90.3%。该研究结果对激光辐照不均匀场景下激光无线能量传输的最大功率点追踪指导意义。
基金supported by The Natural Science Foundation of the Jiangsu Higher Education Institutions of China under grant number 22KJB520003.The project name is"Research on Representation and Reasoning of Knowledge Graphs based on Semantic Mapping".
文摘Although neural methods have been comprehensively applied in different fields,symbolic based logic reasoning is still the main choice for numerous applications based on knowledge graphs.To enhance the efficiency of knowledge graph reasoning,researchers studied how to design parallelalgorithms for reasoning,and take advantage of high-performance architectures,like neural networks.Although parallel algorithms and architectures improve the performance of reasoning to some degree,the task of reasoning is essentially bounded by its computational complexity,i.e.,the PTiMe-Completeness or higher complexities.This means that the task of reasoning is not parallelly tractable.In this work,we investigate the parallel tractability of knowledge graph reasoning from the perspective of parallel complexity.We concentrate on knowledge graphs that are Datalog rewritable.We aim to capture the parallelly tractable classes of knowledge graphs,for which,the task of reasoning falls in the NC complexity.To this end,we employ the computational model of Boolean circuit to formalize knowledge graph reasoning and further obtain all the theoretical results.We then use the results to analyze DHL(Description Horn Logic),a fragment of description logic.We give the properties that ensure the parallel tractability of DHL reasoning.One can utilize our results to check the parallel tractability of real knowledge graphs.In addition,the Boolean circuits proposed in this paper can also be used to construct neural networks to perform knowledge graph reasoning.
