Power consumption is the bottleneck of system performance. Power reduction has become an important issue in digital circuit design, especially for high performance portable devices (such as cell phones, PDAs, etc.). M...Power consumption is the bottleneck of system performance. Power reduction has become an important issue in digital circuit design, especially for high performance portable devices (such as cell phones, PDAs, etc.). Many power reduction techniques have also been proposed from the system level down to the circuit level. High-speed computation has thus become the expected norm from the average user, instead of being the province of the few with access to a powerful mainframe. Power must be added to the portable unit, even when power is available in non-portable applications, the issue of low-power design is becoming critical. Thus, it is evident that methodologies for the design of high-throughput, low-power digital systems are needed. Techniques for low-power operation are shown in this paper, which use the lowest possible supply voltage coupled with architectural, logic style, circuit, and technology optimizations. The threshold vol-tages of the MTCMOS devices for both low and high Vth are constructed as the low threshold Vth is approximately 150 - 200 mv whereas the high threshold Vth is managed by varying the thickness of the oxide Tox. Hence we are using different threshold voltages with minimum voltages and hence considered this project as ultra-low power designing.展开更多
The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the rel...The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the relationships among the length,width,height,and spacing of pin fins;the maximum temperature and temperature difference of the battery module;and the pressure drop of the liquid-cooling plate.Model accuracy is verified via variance analysis.The new liquid-cooling plate enables the power battery to work within an optimal temperature range.Appropriately increasing the length,width,and height and reducing the spacing of pin fins could reduce the temperature of the power battery module and improve the temperature uniformity.However,the pressure drop of the liquid-cooling plate increases.The structural parameters of the pin fins are optimized to minimize the maximum temperature and the temperature difference of the battery module as well as the pressure drop of the liquid-cooling plate.The errors between the values predicted and actual by the simulation test are 0.58%,4%,and 0.48%,respectively,which further verifies the model accuracy.The results reveal the influence of the structural parameters of the pin fins inside the liquid-cooling plate on its heat dissipation performance and pressure drop characteristics.A theoretical basis is provided for the design of liquid-cooling plates in power batteries and the optimization of structural parameters.展开更多
Gold-platinum(Au-Pt)alloy has aroused considerable attention due to its ultra-low magnetic susceptibility(MS)in testing mass(TM)on spacecraft.However,the effect of Au content on the properties of the alloy has not yet...Gold-platinum(Au-Pt)alloy has aroused considerable attention due to its ultra-low magnetic susceptibility(MS)in testing mass(TM)on spacecraft.However,the effect of Au content on the properties of the alloy has not yet been understood.In this study,the composition design of Au-Pt alloy with ultra-low MS was achieved through density functional theory(DFT)and experimental methods.The elastic,thermal properties and electronic structure were systematically investigated,the composition range was further optimized and Au75Pt25 was determined to be the most suitable alloy for TM material.The phase composition of this alloy after cold rolling and solid solution was characterized,indicating a single-phase FCC structure.In addition,there is a good validation between the experimental Vickers hardness and the DFT results.This work provides new insights into the compositional optimization of Au-Pt alloys and lays the foundation for alloy development.展开更多
A power splitter with a wideband arbitrary splitting ratio,which provides flexibility and adaptability in forming photonic devices such as microring resonators and Mach–Zehnder interferometers,proves to be essential ...A power splitter with a wideband arbitrary splitting ratio,which provides flexibility and adaptability in forming photonic devices such as microring resonators and Mach–Zehnder interferometers,proves to be essential in photonic integrated circuits(PICs).We designed and fabricated a directional coupler-based power splitter with a wideband arbitrary splitting ratio and a microring resonator with a wideband uniform extinction ratio(ER)based on artificial gauge field(AGF)optimization.The neural network-aided inverse design method is applied to complete the target.Less than 0.9 dB power splitting variation and 1.6 dB ER variation have been achieved experimentally over a 100-nm bandwidth.Wideband performance,design efficiency,and device compactness are obtained by utilizing this optimization,which indicates great potential and universality in PIC applications.展开更多
Power Designer是一个运行在Windows平台上的系统建模工具,它可以使软件开发人员和数据库管理员协同工作,快速建立起软件的系统模型,为开发一个稳定可靠的软件打下基础。文中通过实例的建设过程,介绍了Power Designer的分析设计过程及...Power Designer是一个运行在Windows平台上的系统建模工具,它可以使软件开发人员和数据库管理员协同工作,快速建立起软件的系统模型,为开发一个稳定可靠的软件打下基础。文中通过实例的建设过程,介绍了Power Designer的分析设计过程及软件代码、数据库的生成过程。展开更多
The structural design and protective methods for the 100 kW shoreline wave power station in China are described in detail. The proper structural type is designed for effective minimization of wave loads and bending st...The structural design and protective methods for the 100 kW shoreline wave power station in China are described in detail. The proper structural type is designed for effective minimization of wave loads and bending stress. Various protective devices are adopted to protect the station in the extreme conditions against excessive power of airflow, excessive torsion of the shaft, over-pressure of the chamber, over-speed of rotation, power failure, and so on. It turns out that the structural design and protective methods for the 100 kW shoreline wave power station are successful.展开更多
Carrying out green energy transformation,implementing clean energy power replacement and supply,and developing a new power system are some primary driving forces needed to fulfill China’s carbon-peak and carbon-neutr...Carrying out green energy transformation,implementing clean energy power replacement and supply,and developing a new power system are some primary driving forces needed to fulfill China’s carbon-peak and carbon-neutral strategic goals.The construction of new power systems in China’s provinces and cities is developing rapidly,and the lack of a typical model promotes the application.The new power system path design should be based on the actual development of the power grid in different regions,energy use characteristics,and other actual needs to carry out the differentiated path design.In this context,this study analyzes the characteristics of the new domestic power system based on the policy background of the new domestic power system,constructs a new model for power system development stage identification,and proposes the overall design of the new power system development path from the power supply,transmission and distribution,and load sides.It also uses the Hebei South Network as an example to explore the development stage of the Hebei South Grid based on actual development needs.Finally,this study designs a novel power system development path for the entire supply and demand chain for the Hebei South Grid to propose ideas for constructing a new power system in China and to help green energy transformation.展开更多
文摘Power consumption is the bottleneck of system performance. Power reduction has become an important issue in digital circuit design, especially for high performance portable devices (such as cell phones, PDAs, etc.). Many power reduction techniques have also been proposed from the system level down to the circuit level. High-speed computation has thus become the expected norm from the average user, instead of being the province of the few with access to a powerful mainframe. Power must be added to the portable unit, even when power is available in non-portable applications, the issue of low-power design is becoming critical. Thus, it is evident that methodologies for the design of high-throughput, low-power digital systems are needed. Techniques for low-power operation are shown in this paper, which use the lowest possible supply voltage coupled with architectural, logic style, circuit, and technology optimizations. The threshold vol-tages of the MTCMOS devices for both low and high Vth are constructed as the low threshold Vth is approximately 150 - 200 mv whereas the high threshold Vth is managed by varying the thickness of the oxide Tox. Hence we are using different threshold voltages with minimum voltages and hence considered this project as ultra-low power designing.
基金supported by the Education and Teaching Research Project of Universities in Fujian Province(FBJY20230167).
文摘The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the relationships among the length,width,height,and spacing of pin fins;the maximum temperature and temperature difference of the battery module;and the pressure drop of the liquid-cooling plate.Model accuracy is verified via variance analysis.The new liquid-cooling plate enables the power battery to work within an optimal temperature range.Appropriately increasing the length,width,and height and reducing the spacing of pin fins could reduce the temperature of the power battery module and improve the temperature uniformity.However,the pressure drop of the liquid-cooling plate increases.The structural parameters of the pin fins are optimized to minimize the maximum temperature and the temperature difference of the battery module as well as the pressure drop of the liquid-cooling plate.The errors between the values predicted and actual by the simulation test are 0.58%,4%,and 0.48%,respectively,which further verifies the model accuracy.The results reveal the influence of the structural parameters of the pin fins inside the liquid-cooling plate on its heat dissipation performance and pressure drop characteristics.A theoretical basis is provided for the design of liquid-cooling plates in power batteries and the optimization of structural parameters.
基金financially supported by the National Key R&D Program of China(No.2021YFC2202300)the National Natural Science Foundation of China(NSFC)(No.51974258)the National College Students Innovation and Entrepreneurship Training Program(No.S202210699134).
文摘Gold-platinum(Au-Pt)alloy has aroused considerable attention due to its ultra-low magnetic susceptibility(MS)in testing mass(TM)on spacecraft.However,the effect of Au content on the properties of the alloy has not yet been understood.In this study,the composition design of Au-Pt alloy with ultra-low MS was achieved through density functional theory(DFT)and experimental methods.The elastic,thermal properties and electronic structure were systematically investigated,the composition range was further optimized and Au75Pt25 was determined to be the most suitable alloy for TM material.The phase composition of this alloy after cold rolling and solid solution was characterized,indicating a single-phase FCC structure.In addition,there is a good validation between the experimental Vickers hardness and the DFT results.This work provides new insights into the compositional optimization of Au-Pt alloys and lays the foundation for alloy development.
基金supported by the National Key R&D Program of China(Grant No.2023YFB2905502)the National Natural Science Foundation of China(Grant Nos.62122047 and 61935011).
文摘A power splitter with a wideband arbitrary splitting ratio,which provides flexibility and adaptability in forming photonic devices such as microring resonators and Mach–Zehnder interferometers,proves to be essential in photonic integrated circuits(PICs).We designed and fabricated a directional coupler-based power splitter with a wideband arbitrary splitting ratio and a microring resonator with a wideband uniform extinction ratio(ER)based on artificial gauge field(AGF)optimization.The neural network-aided inverse design method is applied to complete the target.Less than 0.9 dB power splitting variation and 1.6 dB ER variation have been achieved experimentally over a 100-nm bandwidth.Wideband performance,design efficiency,and device compactness are obtained by utilizing this optimization,which indicates great potential and universality in PIC applications.
文摘The structural design and protective methods for the 100 kW shoreline wave power station in China are described in detail. The proper structural type is designed for effective minimization of wave loads and bending stress. Various protective devices are adopted to protect the station in the extreme conditions against excessive power of airflow, excessive torsion of the shaft, over-pressure of the chamber, over-speed of rotation, power failure, and so on. It turns out that the structural design and protective methods for the 100 kW shoreline wave power station are successful.
基金funded by the State Grid Hebei Electric Power Co.,Ltd projectthe National Natural Science Foundation of China’s major project,“Research on the Construction of China’s Economic Transformation Mode for Carbon Neutrality(72140001)This study is titled“Research on Novel Power System Development Path”。
文摘Carrying out green energy transformation,implementing clean energy power replacement and supply,and developing a new power system are some primary driving forces needed to fulfill China’s carbon-peak and carbon-neutral strategic goals.The construction of new power systems in China’s provinces and cities is developing rapidly,and the lack of a typical model promotes the application.The new power system path design should be based on the actual development of the power grid in different regions,energy use characteristics,and other actual needs to carry out the differentiated path design.In this context,this study analyzes the characteristics of the new domestic power system based on the policy background of the new domestic power system,constructs a new model for power system development stage identification,and proposes the overall design of the new power system development path from the power supply,transmission and distribution,and load sides.It also uses the Hebei South Network as an example to explore the development stage of the Hebei South Grid based on actual development needs.Finally,this study designs a novel power system development path for the entire supply and demand chain for the Hebei South Grid to propose ideas for constructing a new power system in China and to help green energy transformation.
