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Impact of switching frequencies on the TID response of SiC power MOSFETs

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Journal of Semiconductors 2021年第8期42卷 73-76页

作者： Sheng Yang Xiaowen Liang Jiangwei Cui qiwen zheng Jing Sun Mohan Liu Dang Zhang Haonan Feng Xuefeng Yu Chuanfeng Xiang Yudong Li Qi Guo Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics and ChemistryChinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Electronic Information Material and Device Urumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Different switching frequencies are required when SiC metal-oxide-semiconductor field-effect transistors(MOSFETs)are switching in a space *** this study,the total ionizing dose(TID)responses of SiC power MOSFETs are investigated under different switching frequencies from 1 kHz to 10 MHz.A significant shift was observed in the threshold voltage as the frequency increased,which resulted in premature failure of the drain-source breakdown voltage and drain-source leakage *** degradation is attributed to the high activation and low recovery rates of traps at high *** results of this study suggest that a targeted TID irradiation test evaluation method can be developed according to the actual switching frequency of SiC power MOSFETs.

关键词： SiC power MOSFET switching frequency oxide trap total ionizing dose transistor semiconductor theory

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液/固晶面润湿性实验与模拟研究方法

材料导报 2022年第9期36卷 139-150页

作者：郑棋文范同祥上海交通大学金属基复合材料国家重点实验室

液/固晶面润湿问题在钎焊、金属基复合材料液相法制备等领域都有着重要研究意义。研究发现，固体晶面结构会显著影响液/固界面润湿性。研究液体在固体特定晶面上的润湿行为，对于深入理解润湿过程及更有针对性地改善材料液/固界面润湿... 详细信息

液/固晶面润湿问题在钎焊、金属基复合材料液相法制备等领域都有着重要研究意义。研究发现，固体晶面结构会显著影响液/固界面润湿性。研究液体在固体特定晶面上的润湿行为，对于深入理解润湿过程及更有针对性地改善材料液/固界面润湿性具有重要意义。目前研究液/固晶面润湿性的实验测量方法主要为座滴法，然而该方法针对强弱界面结合体系的测量结果对实验条件均较敏感，且受限于特定晶面基板是否容易制备，因此仍不能在液/固晶面润湿性的研究中推广采用。微观模拟方法不仅可以建立不同晶面的固体结构，同时有效避免了实验条件的影响，故对预测实验结果具有独特的优势。用于液/固晶面润湿性研究的微观尺度模拟方法包括分子动力学、第一性原理计算以及Ab-initio分子动力学。目前分子动力学方法主要应用于强界面结合的金属/金属体系，通过模拟实际物理条件下的熔化和润湿过程，可研究润湿性、界面反应、铺展动力学以及探究温度对润湿的影响，然而有效势函数的缺乏限制了该方法在其他体系的推广，且势计算结果的准确性与可靠性严重依赖势函数的参数选择。电子尺度的第一性原理计算可探究弱界面结合体系中不同晶面取向下润湿性差异的根本原因、强界面结合体系中界面微观构型对初始润湿性的影响、反应后熔体/反应产物界面成键特点以及平衡润湿性差异，但是该方法的缺点是计算原子个数有限，需要绝对零度的模拟温度。Ab-initio分子动力学是前两种方法的结合，虽然不依赖于势函数的参数选择，但是仍受限于计算原子个数和模拟效率。本文从每种方法的基本原理、实验操作或模型构建及优缺点等三个方面，阐述了弱/强界面结合体系中液/固晶面润湿性研究进展，并对三种微观模拟方法的未来改进方向进行了展望。

关键词：液/固界面润湿晶面结构实验测量分子动力学第一性原理 Ab-initio分子动力学

Survival difference between EGFR Del19 and L858R mutant advanced non-small cell lung cancer patients receiving gefitinib:a propensity score matching analysis

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Chinese Journal of Cancer Research 2017年第6期29卷 553-560页

作者： Minglei Zhuo qiwen zheng Jun Zhao Meina Wu Tongtong An Yuyan Wang Jianjie Li Shuhang Wang Jia Zhong Xue Yang Hanxiao Chen Bo Jia Zhi Dong Emei Gao JingjingWang Ziping Wang Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of Thoracic Medical OncologyPeking University Cancer Hospital&InstituteBeijing 100142China Department of Epidermiololgy and Biostatistics School of Public HealthPeking UniversityBeijing 100191China

Objective： Although superior clinical benefits of epidermal growth factor receptor （EGFR） tyrosine kinase inhibitors （TKIs） in the treatment of advanced non-small-cell lung cancer （NSCLC） had been reported, the survival difference between exon 19 deletion （Dell9） and exon 21 Leu858Arg substitution （L858R） remains controversial. The purpose of this study is to investigate the differences in progression-free survival （PFS） and overall survival （OS） between different EGFR mutant subtypes among advanced NSCLC patients receiving gefitinib. Methods： There were 204 advanced NSCLC patients with EGFR mutations treated with gefitinib were enrolled in this retrospective cohort study. Patients were divided into the EGFR Dell9 group and the L858R mutated group according to their mutant subtype. Propensity score matching （PSM） was conducted by using a nearest-neighbor algorithm （1：1） to adjust for demographical and clinical covariates. Survival curves were constructed with the Kaplan-Meier method and compared by using the log-rank test. Results： The PFS in Dell9 group was similar to that in the L858R group [before PSM 8.6 vs. 7.2 months, P=0.072; after PSM 7.3 vs. 7.2 months, P=0.155]. No differences were detected in OS between the L858R and the Dell9 group （before PSM 17.8 vs. 13.1 months, P=0.253; after PSM 16.9 vs. 13.1 months, P=0.339）. The Dell9 group was significantly younger compared with the L858R mutation group in age （P=0.015）. Conclusions： No significant difference was found in the PFS or OS between the Dell9 and L858R mutant NSCLC patients receiving gefitinib. The age gap might contribute to the survival differences between Dell9 and L858R groups. PSM is of important value to the elimination of potential bias.

关键词： Non-small-cell lung cancer epidermal growth factor receptor tyrosine kinase inhibitors survival propensity score matching

Multi-smart car control system design and research based on ZigBee

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Multi-smart car control system design and research based on ...

Predicting the risk for narcolepsy based on genetic risk scores of candidate loci

第26届中国控制与决策会议

作者： Chuan Wang Zhongyu Shen Engang Tian qiwen zheng School of Electrical and Automation Engineering Nanjing Normal University

Firstly, the multi-smart car formation control system is designed by using distributed control architecture. The wireless communications, the magnetic field sensors, motor drives and other hardware modules are designed. The smart car navigation is achieved by magnetic field detection. Then the multi-smart car cooperative control self-organizing wireless communication network is designed by ZigBee. The embedded C/OS-II real-time operating system is transplanted into the smart car. According to the requirements for multi- smart car cooperative control, the linear optimal quadratic fleet tracking control algorithm is utilized to realize multi-smart car start and stop formations, and uniform and ramp control. The collaborative communication negotiation intersection algorithms are applied to achieve crossing collaborative tasks of the smart car. Finally, the experimental results show that the designed ZigBee wireless communication network meets the requirements for the collaboration control, formation control and road junction collaborating control of the smart car.

关键词： ZigBee wireless communication network embedded operating system multi-smart car formation control

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Predicting the risk for narcolepsy based on genetic risk sco...

中国睡眠研究会第十一届全国学术年会

作者： Hui Ouyang Fang Han Zechen Zhou Dafang Chen qiwen zheng Yangyang Wang Jun Zhang Peking university people’s hospital Peking university health science center

Background Narcolepsy is a life-long neurological disorder characterized by excessive daytime sleepiness（EDS）,cataplexy, sleep paralysis, hallucinations, and disrupted nocturnal *** has been reported that narcolepsy patients suffer from function impairment Recently, the Genome-wide association studies（GWASs） have identified a large number of single-nucleotide polymorphisms（SNPs） associated with narcolepsy, and evaluated the impact of these single genes on the onset of narcolepsy. However, studying the effects of single genes on the risk of narcolepsy is not enough to predict the onset of narcolepsy, meanwhile, the sum impact of these SNPs on defining the genomic risk of narcolepsy remains unknown. Therefore, in the present study, we aim to construct genetic risk scores（GRSs） for narcolepsy and then investigate associations between genetic risk scores（GRSs） and narcolepsy, as well as their predictive *** A case-control study consisting of 903 narcolepsy patients recruited from the sleep center of peking university, people’s hospital and 1,981 healthy control subjects was performed. DNA samples were genotyped on the Affymetrix Axiom CHB array. Genotypes were called using Affymetrix Genotyping *** HLA region was genotyped using the Illumina ImmunoChip. Imputation of 1000 Genomes project SNPs from this array using IMPUTE2 and the PhaseⅠv2, cosmopolitan（integrated） reference panel, build 37, Individuals with call rate＜99%, MAF＜1%, HWE p value＜0.001, or that were outliers following principal components analysis, or related, were removed. After quality control, 903 cases and 1981 controls were left. In total, 32 SNPs previously reported to confer susceptibility to narcolepsy were assessed for association with narcolepsy risk. Subsequently, we constructed four GRS groups comprising reported narcolepsy susceptibility SNPs located in different genomic regions, and tested their association with narcolepsy risk using a regression model and then examine th

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日志模板提取的FT-Tree改进算法研究

南京师大学报（自然科学版） 2021年第2期44卷 121-126页

作者：顾海艳郑淇文江苏警官学院计算机信息与网络安全系江苏南京210031

计算机日志能够真实、全面记录事件信息,已经作为一种电子证据在侦查办案中得到普遍应用.要实现对海量日志信息的快速自动分析,需要有高效可靠的日志模板提取方法.鉴于目前日志模板提取方法存在的不足,本文以网络服务器日志作为模板提... 详细信息

计算机日志能够真实、全面记录事件信息,已经作为一种电子证据在侦查办案中得到普遍应用.要实现对海量日志信息的快速自动分析,需要有高效可靠的日志模板提取方法.鉴于目前日志模板提取方法存在的不足,本文以网络服务器日志作为模板提取的研究对象,基于FT-Tree算法,提出了利用Apriori算法计算剪枝阈值,再利用该值控制剪枝的FT-Tree改进算法,并以某高校网络服务器真实日志进行了模板提取实验.结果表明,改进算法较之FT-Tree算法显著提高了日志模板提取的准确度,能更好地满足实际应用需要.

关键词：日志模板提取方法 FT-Tree算法 Apriori算法改进算法

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无线通信网络的多智能小车编队控制系统

东南大学学报（自然科学版） 2013年第A01期43卷 18-21页

作者：申忠宇郑启文王川张少华张倩南京师范大学电气与自动化工程学院南京210042 博世汽车部件(苏州)有限公司苏州215000

首先设计了基于ARM Cortex-M3的智能小车控制系统,利用模块化理念设计了无线通信、磁场检测传感器、电机驱动等硬件模块,采用ZigBee设计了多智能小车协作控制的车载自组织无线通信网络,利用磁场检测完成小车的导航方式,采用旋转编码器... 详细信息

首先设计了基于ARM Cortex-M3的智能小车控制系统,利用模块化理念设计了无线通信、磁场检测传感器、电机驱动等硬件模块,采用ZigBee设计了多智能小车协作控制的车载自组织无线通信网络,利用磁场检测完成小车的导航方式,采用旋转编码器实现小车的测速功能.然后在智能小车上移植了嵌入式μC/OS-Ⅱ实时操作系统,根据多智能小车协作控制要求,设计了智能小车分布式自主决策程序,实现多智能小车自由运行、队列跟随和路口协作等运行模式.最后采用线性最优二次型的车队跟随控制算法,实现多智能小车编队的启停、匀速和加减速控制,利用通信协商的路口协作算法,实现多智能小车路口协作任务.实验结果表明,设计的无线通信网络的多智能小车系统能够满足多智能小车协作控制、编队控制和路口协作控制要求.

关键词： ZigBee 无线通信网络智能小车嵌入式操作系统多智能小车编队

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： YongFei zheng School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin

Safe Motion Planning and Control Framework for Automated Vehicles with Zonotopic TRMPC

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Engineering 2024年第2期33卷 146-159页

作者： Hao zheng Yinong Li Ling zheng Ehsan Hashemi State Key Laboratory of Mechanical Transmissions College of Mechanical and Vehicle EngineeringChongqing UniversityChongqing 400044China Department of Mechanical Engineering University of AlbertaEdmontonAB T6G 2H5Canada

Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning *** address this issue,this study proposes a safe motion planning and control(SMPAC)framework for *** the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller *** the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is *** safety sets provide the basis for the subsequent evaluation and ranking of the generated *** efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the *** result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties.

关键词： Automated vehicles Automated driving Motion planning Motion control Tube MPC Zonotope