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Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： zhuo Li Feng Jiang Zhengyi Jiang Zige Tian Tian Qiu Tao Zhang Qiuling Wen Xizhao Lu Jing Lu Hui huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for SCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

基于PH分布和MAP的备件(s,S)库存模型

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系统工程理论与实践 2009年第6期29卷 107-114页

作者：陈童黄卓郭波国防科技大学信息系统与管理学院系统工程系长沙410073

以包含多个相同部件的系统为研究对象,采用Phase-type(PH)分布代替指数分布等经典分布作为备件寿命、换件维修时间以及库存补充时间的基本假设,推导出该系统的备件需求过程为马尔可夫到达过程(Markovian Arrival Process,MAP);然后在此... 详细信息

以包含多个相同部件的系统为研究对象,采用Phase-type(PH)分布代替指数分布等经典分布作为备件寿命、换件维修时间以及库存补充时间的基本假设,推导出该系统的备件需求过程为马尔可夫到达过程(Markovian Arrival Process,MAP);然后在此基础上,研究了(s,S)库存模型,给出了该库存模型首次订货时间、再订货周期、缺货时间的相关分布和参数,最后通过一个算例说明了模型的有效性.

关键词： Phase—type分布马尔可夫到达过程备件需求库存模型

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ACPH分布数据拟合的封闭形式EM算法

系统工程理论与实践 2010年第4期30卷 679-688页

作者：黄卓任培郭波国防科技大学信息系统与管理学院系统工程系长沙410073

ACPH(Acyclic continuous phase type)分布类在[0,+∞)上的全体连续概率分布函数类中稠密,是具有通用性的概率分布类.提出采用EM(Expectation maximization)算法解决ACPH分布的数据拟合问题,给出了ACPH分布数据拟合的封闭形式EM算法,并... 详细信息

ACPH(Acyclic continuous phase type)分布类在[0,+∞)上的全体连续概率分布函数类中稠密,是具有通用性的概率分布类.提出采用EM(Expectation maximization)算法解决ACPH分布的数据拟合问题,给出了ACPH分布数据拟合的封闭形式EM算法,并通过6个拟合实例验证了该方法的有效性.

关键词： PH分布 ACPH分布封闭形式 EM算法数据拟合

Vulnerability and Conservation of Nearshore Cetaceans to Increasing Vessel Traffic:The Indo-Pacific Humpback Dolphin in the South China Sea

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Journal of Ocean University of China 2024年第4期23卷 1003-1014页

作者： LUO Dingyu GUO Lang huang Nuoyan WANG Hongri ZENG Chen TANG Xikai XU zhuo WU Yuping SUN Xian School of Marine Sciences Zhuhai Key Laboratory of Marine Bioresources and EnvironmentGuangdong Provincial Key Laboratory of Marine Resources and Coastal EngineeringPearl River Estuary Marine Ecosystem Research Sta-tionMinistry of EducationSun Yat-Sen UniversitySouthern Marine Science and Engineering Guangdong Labora-tory(Zhuhai)Zhuhai 519082China

A comprehensive risk assessment to evaluate the vulnerability of the nearshore cetaceans to increasing marine traffic is *** this study,the risk to Indo-Pacific humpback dolphins(Sousa chinensis)in the main habitats in China was assessed based on a semiquantitative spatial vulnerability analysis.85%of the(sub)population which overlapped with the lanes of ferries and/or cargo vessels,with exposure scores of 1.23±0.31(calculated based on the proportion of sea routes that overlap the dolphin’s range).A combination of high exposure to the sea routes and sensitivity to marine traffic would render the(sub)populations to be highly vulnerable(EPRE:5.21 and XM:4.47).A low frequency of vessels and an awareness of the ecology assures a low vulnerability(SH:2.43,EZ:2.73).Uncertainty scores were commonly lower for the higher vulnerable populations,and higher for the lower vulnerable populations,suggesting additional field data and more monitoring are *** years of field data have been used to analyze the influences of various types of marine traffic on humpback dolphin *** and non-fishing vessels were significantly different(χ^(2)=65.19,p<0.01).The humpback dolphins were attracted by fishing vessels(83.1%)but avoided non-fishing vessels(95.2%).We recommend a management with seasonal and geographical constraints,to balance economic development and environmental conservation.

关键词： Indo-Pacific humpback dolphin vessel impacts risk analysis protection strategy

Effects of Si and Ce on the microstructure and hydrogen storage property of Ti_(26.5)Cr_(20)V_(45)Fe_(8.5)Ce_(0.5) alloy

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Science China(Technological Sciences) 2009年第1期52卷 256-259页

作者： MI Jing, LIU XiaoPeng, LI ZhiNian, JIANG LiJun, huang zhuo & WANG ShuMao Energy Material and Technology Research Institute, General Research Institute for Non-ferrous Metals, Beijing 100088, China Energy Material and Technology Research Institute General Research Institute for Non-ferrous Metals Beijing China

In this paper, the effects of Si and Ce on the microstructure and hydrogen storage property of Ti26.5 Cr20V45Fe8.5Ce0.5 alloy were studied, respectively. First of all, effects of Si on the microstructure and hydrogen storage properties of Ti26.5Cr20(V45Fe8.5)1?xSixCe0.5 (x = 0, 0.5, 1.0, 1.5 and 2.0 at%) alloys were studied by X-ray diffraction, scanning electron microscopy and P-C isotherm measurements. As the Si addition increases, the hydrogen absorption capacities of alloys decrease but the equilibrium pressure increases, due to the formation of Laves phase. Secondly, the effect of Ce on Ti26.5Cr20 (V45Fe8.5)0.98Si2 alloy was studied. It was found that Ce addition is an effective way to eliminate the effect of Si on the hydrogen storage properties of the alloy.

关键词： hydrogen storage materials Ti-V based alloy Laves phase

基于遗传算法和蒙特卡洛仿真的设备维修策略优化

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东南大学学报（自然科学版） 2006年第6期36卷 941-945页

作者：苏春黄茁许映秋东南大学机械工程学院南京211189

以部件寿命服从非指数分布、维修属于非马尔可夫过程复杂设备为对象,以系统可用度及广义维护成本为优化目标,以预防性维修周期为优化变量,基于蒙特卡洛仿真和遗传算法研究预防性维修策略的优化问题.建立了设备维修过程的优化模型,将遗... 详细信息

以部件寿命服从非指数分布、维修属于非马尔可夫过程复杂设备为对象,以系统可用度及广义维护成本为优化目标,以预防性维修周期为优化变量,基于蒙特卡洛仿真和遗传算法研究预防性维修策略的优化问题.建立了设备维修过程的优化模型,将遗传算法中的个体进化搜索用于维修策略优化,提出基于路集的系统状态分析以及采用部件故障屏蔽法解决维修过程仿真中部件过度故障问题,并通过建立个体仿真历史纪录和优先删除适应度低的个体纪录等方法以提高仿真效率及优化效果.最后以液压-机械复合传动系统为例,验证方法的有效性.

关键词：遗传算法维护策略蒙特卡洛仿真传动系统优化

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考虑时间不确定性的研制过程评估与优化方法

机械工程学报 2008年第6期44卷 248-252页

作者：梁亮黄卓郭波国防科技大学信息系统与管理学院长沙410073

迭代是研制过程的一个基本特征。针对产品研制中的顺序设计迭代,考虑设计活动完成时间的不确定性,采用多阶段Markov过程对研制过程进行建模,建立任务完成时间预测模型。在此基础上以给定风险下的完成时间最小为目标,对研制过程进行优化... 详细信息

迭代是研制过程的一个基本特征。针对产品研制中的顺序设计迭代,考虑设计活动完成时间的不确定性,采用多阶段Markov过程对研制过程进行建模,建立任务完成时间预测模型。在此基础上以给定风险下的完成时间最小为目标,对研制过程进行优化建模。实例分析说明了时间预测与过程优化的建模方法,并用仿真结果进行了对比验证。分析表明,该方法能较好地反映研制过程顺序迭代特点,可为优化产品研制过程、缩短研制周期提供有效工具。

关键词：研制过程设计迭代设计结构矩阵时间不确定性

Power supply for generating frequency-variable resonant magnetic perturbations on the J-TEXT tokamak

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Plasma Science and Technology 2018年第8期20卷 96-103页

作者： Guo XU Bo RAO Yonghua DING Mao LI Da LI Ruo JIA Minxiong YAN Xinke JI Nengchao WANG zhuo huang Daojing GUO Lai PENG State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and TechnologyWuhan 430074People＇s Republic of China School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074People＇s Republic of China

To further research the response of the tearing mode（TM） to dynamic resonant magnetic perturbation（DRMP） on the J-TEXT tokamak, a modified series resonant inverter power supply（MSRIPS） with a function of discrete variable frequency is designed for DRMP coils in this study. The MSRIPS is an AC–DC–AC converter, including a phase-controlled rectifier, an LC filter, an insulated gate bipolar transistor（IGBT） full bridge, a matching transformer, three resonant capacitors with different capacitance values, and three corresponding silicon controlled rectifier（SCR） switches. The function of discrete variable frequency is realized by switching over different resonant capacitors with corresponding SCR switches while matching the corresponding driving frequency of the IGBT full bridge. A detailed switching strategy of the SCR switch is put forward to obtain sinusoidal current waveform and realize current waveform smooth transition during frequency conversion. In addition, a resistor and thyristor bleeder is designed to protect the SCR switch from overvoltage. Manufacturing of the MSRIPS is completed, and the MSRIPS equipment can output current with an amplitude of 1.5 kA when its working frequency jumps among different frequencies. Moreover, the current waveform is sinusoidal and can smoothly transition during frequency conversion. Furthermore, the transition time when the current amplitude rises from zero to a steady state is less than 2 ms during frequency conversion. By using the MSRIPS, the expected discrete variable frequency DRMP is generated, and the phenomenon of the TM being locked to the discrete variable frequency DRMP is observed on the J-TEXT tokamak.

关键词： tearing mode J-TEXT series resonant inverter discrete variable frequency silicon controlled rectifier

机器人足球训练中视觉感知与动作执行同步机制

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东南大学学报（自然科学版） 2006年第3期36卷 361-365页

作者：许映秋黄茁江大伟东南大学机械工程学院南京210096 东南大学计算机科学与工程学院南京210096

主要研究RoboCup训练中球员视觉感知与动作执行同步的技术.在全面分析RoboCup现有同步方法存在问题的基础上,提出一种动态的视角调整方法,即通过对球员视角宽度的调整控制视觉信息到达的时刻,结合动作指令发送的特殊策略,实现球员向服... 详细信息

主要研究RoboCup训练中球员视觉感知与动作执行同步的技术.在全面分析RoboCup现有同步方法存在问题的基础上,提出一种动态的视角调整方法,即通过对球员视角宽度的调整控制视觉信息到达的时刻,结合动作指令发送的特殊策略,实现球员向服务器发送指令时机的优化,以达到最佳同步效果.关于球员视角宽度动态切换的实现,具体包括:基于增强视觉检测的视角切换与分类视角动态切换2种方法.对比实验证实了该同步技术的优越性.

关键词：视觉感知动作执行同步机制足球机器人视角切换