In this paper, a 4H-SiC semi-superjunction （S J） Schottky barrier diode is analysed and simulated. The semi-SJ structure has an optimized design and a specific on-resistance lower than that of conventional SJ struct...In this paper, a 4H-SiC semi-superjunction （S J） Schottky barrier diode is analysed and simulated. The semi-SJ structure has an optimized design and a specific on-resistance lower than that of conventional SJ structures, which can be achieved without increasing the process difficulty. The simulation results show that the specific on-resistance and the softness factor depend on the aspect and thickness ratios, and that by using the semi-SJ structure, specific on-resistance can be reduced without decreasing the softness factor. It is observed that a trade-off exists between the specific on-resistance and the softness of the diode.展开更多
Hyaluronic acid hydrogels (HAHs) were synthesized by immersing the microbeads in phosphate buffered saline solution to assess short term biocompatibility of the gels by means of the rabbit pyrogen test and the bacteri...Hyaluronic acid hydrogels (HAHs) were synthesized by immersing the microbeads in phosphate buffered saline solution to assess short term biocompatibility of the gels by means of the rabbit pyrogen test and the bacterial endotoxin test. The rise in body temperature of 3 male New Zealand white rabbits weighing about 2~3 kg (12~16 weeks old) following intravenous injection of the test article (10 mL/kg) was mo nitored at 30 min intervals in 3 h to examine the pyrogenicity. No rabbits showed an individual rise in temperature of 0.5oC or more above its respective control temperature. The temperature rises of the rabbits after injection were 0.12oC, 0.13oC, and 0.18oC, respectively, sugge sting that HAH meets the requirements for the absence of pyrogens. The bacterial endotoxin test revealed that the concentration of endoto xins required to cause the lysate to clot under standard conditions was < 0.125 EU/mL. Comparing the HAHs that was synthesized in this experiment to the ones approved by FDA, the amount of < 0.125 EU/mL endotoxins is relatively safe and effective. The test solution did not contain any interfering factors under the ex perimental conditions used. It is conceivable that the HAHs are likely to be suitable injectable dermal filler for facial soft tissue augmentation due to the absence of展开更多
大规模分布式新能源接入导致新型配电系统面临“节点-网络”双重灵活性不足风险,使得规划配置智能混合储能软开关(hybrid energy storage system-soft open point,HESSSOP),实现节点型与网络型异质灵活资源协同控制,成为提升节点灵活调...大规模分布式新能源接入导致新型配电系统面临“节点-网络”双重灵活性不足风险,使得规划配置智能混合储能软开关(hybrid energy storage system-soft open point,HESSSOP),实现节点型与网络型异质灵活资源协同控制,成为提升节点灵活调节支撑和网络传输安全裕度的重要技术手段。对此,建立面向HESS-SOP融入支撑“节点-网络”双重灵活性的新型配电系统协同规划-运行模型。首先,研究SOP引入HESS组成HESS-SOP的拓扑结构和联合调节特性;然后,引入转移分布因子以线路为视角建立含HESSSOP的新型配电系统灵活性供需平衡模型,解析“节点-网络”灵活性供需平衡机理,并建立“节点-网络”双维度灵活性指标;其次,采用有功潮流灵敏度法与希尔伯特-黄变换法对HESS-SOP分别进行选址与初始参数配置,并建立考虑HESS-SOP“节点-网络”双重灵活性调控潜力的规划-运行联合优化模型,并采用混合算法进行求解;最后,基于改进的IEEE33节点系统开展算例分析。结果表明:所提出的灵活性指标能准确量化评估系统“节点-网络”双维度灵活性,所建立的考虑HESS-SOP灵活性调控潜力的规划-运行联合优化模型能有效提高配电系统运行的经济性与灵活性。展开更多
This paper presents a new method for soft error detection using software redundancy (SEDSR) that is able to detect transient faults. Soft errors damage the control flow and data of programs and designers usually use h...This paper presents a new method for soft error detection using software redundancy (SEDSR) that is able to detect transient faults. Soft errors damage the control flow and data of programs and designers usually use hardware-based solutions to handle them. Software-based techniques for soft error detection force less cost and delay to systems and do not change their configuration. Therefore, these kinds of methods are appropriate alternatives for hardware-based techniques. SEDSR has two separate parts for data and control flow errors detection. Fault injection method is used to compare SEDSR with previous methods of this field based on the new parameter of “Evaluation Factor” that takes in account fault coverage, memory and performance overheads. These parameters are important in real time safety critical applications. Experimental results on SPEC2000 and some traditional benchmarks of this field show that SEDSR is much better than previous methods of this field. SEDSR’s evaluation factor is about 50% better than other methods of this field. These results show its success in satisfaction of the existing tradeoff between fault coverage, performance and memory overheads.展开更多
文摘为进一步提高系统灵活性及效率,提出了一种数字化软开关技术的单相弧焊电源的功率因数校正电路,论述了系统整体硬件结构、选用的软开关升压电路拓扑原理以及软件设计思路,并进行了电子负载和非熔化极惰性气体保护电弧焊(tungsten inert gas welding,TIG)两种情况下软开关功率因数校正结果的验证.通过谐振电容以及开关管的电信号,证实了电路成功实现了零电流导通和零电压关断;通过电子负载在不同功率下功率因数和效率的测试,验证了功率因数可达到0.985以上,并且效率整体上得到了提升;通过不同焊接电流下TIG弧焊试验,对校正的电信号进行了分析,证实了针对单相弧焊电源功率因数校正的成效.
基金Project supported by the National Natural Science Foundation of China(Grant No.60876050)the Research Fund for Excellent Doctor Degree Thesis of Xi'an University of Technology,China
文摘In this paper, a 4H-SiC semi-superjunction （S J） Schottky barrier diode is analysed and simulated. The semi-SJ structure has an optimized design and a specific on-resistance lower than that of conventional SJ structures, which can be achieved without increasing the process difficulty. The simulation results show that the specific on-resistance and the softness factor depend on the aspect and thickness ratios, and that by using the semi-SJ structure, specific on-resistance can be reduced without decreasing the softness factor. It is observed that a trade-off exists between the specific on-resistance and the softness of the diode.
文摘Hyaluronic acid hydrogels (HAHs) were synthesized by immersing the microbeads in phosphate buffered saline solution to assess short term biocompatibility of the gels by means of the rabbit pyrogen test and the bacterial endotoxin test. The rise in body temperature of 3 male New Zealand white rabbits weighing about 2~3 kg (12~16 weeks old) following intravenous injection of the test article (10 mL/kg) was mo nitored at 30 min intervals in 3 h to examine the pyrogenicity. No rabbits showed an individual rise in temperature of 0.5oC or more above its respective control temperature. The temperature rises of the rabbits after injection were 0.12oC, 0.13oC, and 0.18oC, respectively, sugge sting that HAH meets the requirements for the absence of pyrogens. The bacterial endotoxin test revealed that the concentration of endoto xins required to cause the lysate to clot under standard conditions was < 0.125 EU/mL. Comparing the HAHs that was synthesized in this experiment to the ones approved by FDA, the amount of < 0.125 EU/mL endotoxins is relatively safe and effective. The test solution did not contain any interfering factors under the ex perimental conditions used. It is conceivable that the HAHs are likely to be suitable injectable dermal filler for facial soft tissue augmentation due to the absence of
文摘大规模分布式新能源接入导致新型配电系统面临“节点-网络”双重灵活性不足风险,使得规划配置智能混合储能软开关(hybrid energy storage system-soft open point,HESSSOP),实现节点型与网络型异质灵活资源协同控制,成为提升节点灵活调节支撑和网络传输安全裕度的重要技术手段。对此,建立面向HESS-SOP融入支撑“节点-网络”双重灵活性的新型配电系统协同规划-运行模型。首先,研究SOP引入HESS组成HESS-SOP的拓扑结构和联合调节特性;然后,引入转移分布因子以线路为视角建立含HESSSOP的新型配电系统灵活性供需平衡模型,解析“节点-网络”灵活性供需平衡机理,并建立“节点-网络”双维度灵活性指标;其次,采用有功潮流灵敏度法与希尔伯特-黄变换法对HESS-SOP分别进行选址与初始参数配置,并建立考虑HESS-SOP“节点-网络”双重灵活性调控潜力的规划-运行联合优化模型,并采用混合算法进行求解;最后,基于改进的IEEE33节点系统开展算例分析。结果表明:所提出的灵活性指标能准确量化评估系统“节点-网络”双维度灵活性,所建立的考虑HESS-SOP灵活性调控潜力的规划-运行联合优化模型能有效提高配电系统运行的经济性与灵活性。
文摘This paper presents a new method for soft error detection using software redundancy (SEDSR) that is able to detect transient faults. Soft errors damage the control flow and data of programs and designers usually use hardware-based solutions to handle them. Software-based techniques for soft error detection force less cost and delay to systems and do not change their configuration. Therefore, these kinds of methods are appropriate alternatives for hardware-based techniques. SEDSR has two separate parts for data and control flow errors detection. Fault injection method is used to compare SEDSR with previous methods of this field based on the new parameter of “Evaluation Factor” that takes in account fault coverage, memory and performance overheads. These parameters are important in real time safety critical applications. Experimental results on SPEC2000 and some traditional benchmarks of this field show that SEDSR is much better than previous methods of this field. SEDSR’s evaluation factor is about 50% better than other methods of this field. These results show its success in satisfaction of the existing tradeoff between fault coverage, performance and memory overheads.
