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Occurrence andmineral chemistry of chromite and xieite in the Suizhou L6 chondrite

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Science China Earth Sciences 2011年第7期54卷 998-1010页

作者： XIE XlanDe chen ming WANG ChunYun Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The occurrence and mineral chemistry of chromite and its high-pressure phase xieite in the Suizhou meteorite were studied by different modem micromineralogical techniques. Three types of occurrences for chromite were observed in the Suizhou L6 chondrite： coarse chromite grains, cluster of chromite fragments in molten plagioclase, and exsolution lamellar chromite in oli- vine. All the chromite grains of the first two types are remarkably similar in chemical compositions, but the composition of exsolution chromite is inhomogeneous and variable in A1203 content. Xieite is a post-spinel CT-phase of chromite firstly found in the Suizhou meteorite. Three types of occurrences of xieite have also been revealed in this meteorite： coarse xieite grains, complex three-zone-grains consisting of the inner xieite, the intermediate lamellae-like CF-phase and the outer chromite phase, and two-phase-grains consisting of xieite and one of the high-pressure silicate minerals lingunite, ringwoodite or majorite. The curved boundary between xieite and the silicate half in two-phase grains is indicative of some partial or even full melting of the silicate phase. EPMA and EDS results show that the compositions of xieite inside/contacting the shock veins are also identical to that of chromite outside the veins. However, some element diffusion appeared in between the xieite and the silicate half in the two-phase grains, namely, some of Al^3＋ from lingunite, or Fe^2＋ from ringwoodite migrated to xieite, and some of Cr^3＋ migrated from xieite to lingunite or ringwoodite. Majorite in two-phase grains shows remarkable decrease of SiO2 and MgO, and notable increase of Al2O3 and CaO, indicating that its host mineral pyroxene was fully molten and mixed with the surrounding silicate melt of the vein matrix. The complexity in mineral chemistry of these two-phase grains in shock veins can be explained by the much higher shock peak temperature in shock veins （1800-2000℃） than in unmelted main body （-100

关键词： chromite xieite occurrence chemical composition shock metamorphism Suizhou meteorite

Comparison of D-flip-flops and D-latches:influence on SET susceptibility of the clock distribution network

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Nuclear Science and Techniques 2019年第2期30卷 91-100页

作者： Pei-Pei Hao Shu-ming chen College of Computer National University of Defense Technology

As technology scales down, clock distribution networks(CDNs) in integrated circuits(ICs) are becoming increasingly sensitive to single-event transients(SETs).The SET occurring in the CDN can even lead to failure of the entire circuit system. Understanding the factors that influence the SET sensitivity of the CDN is crucial to achieving radiation hardening of the CDN and realizing the design of highly reliable ICs. In this paper, the influences of different sequential elements(D-flip-flops and D-latches, the two most commonly used sequential elements in modern synchronous digital systems) on the SET susceptibility of the CDN were quantitatively studied. Electrical simulation and heavy ion experiment results reveal that the CDN-SET-induced incorrect latching is much more likely to occur in DFF and DFF-based designs. This can supply guidelines for the design of IC with high reliability.

关键词： Clock distribution network D-flip-flop D-latch Reliability Single-event transient Susceptibility

A Class of New Large-Update Primal-Dual Interior-Point Algorithms for P＊（k） Nonlinear Complementarity Problems

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Acta Mathematica Sinica,English Series 2011年第10期27卷 1979-1994页

作者： Hua Ping chen ming Wang ZHANG College of Science China Three Gorges University Yichang 443002 P. R. China

In this paper we propose a class of new large-update primal-dual interior-point algorithms for P.（k） nonlinear complementarity problem （NCP）, which are based on a class of kernel functions investigated by Bai et al. in their recent work for linear optimization （LO）. The arguments for the algorithms are followed as Peng et al.＇s for P.（n） complementarity problem based on the self-regular functions [Peng, J., Roos, C., Terlaky, T.： Self-Regularity： A New Paradigm for Primal-Dual Interior- Point Algorithms, Princeton University Press, Princeton, 2002]. It is worth mentioning that since this class of kernel functions includes a class of non-self-regular functions as special case, so our algorithms are different from Peng et al.＇s and the corresponding analysis is simpler than theirs. The ultimate goal of the paper is to show that the algorithms based on these functions have favorable polynomial complexity.

关键词： Large-update method interior-point algorithm nonlinear complementarity problem non- self-regular function polynomial complexity

Long-term outcome and efficacy of endoscopic hemorrhoid ligation for symptomatic internal hemorrhoids

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World Journal of Gastroenterology 2011年第19期17卷 2431-2436页

作者： cheng-Tang Chiu chen-ming Hsu Department of Gastroenterology and Hepatology Lin-Kou Chang Gung Memorial HospitalChang Gung University College of Medicine

AIM:To assess the long-term outcome of endoscopic hemorrhoid ligation (EHL) for the treatment of symptomatic internal ***:A total of 759 consecutive patients (415 males and 344 females) were *** presentations were rectal bleeding (593 patients) and mucosal prolapse (166 patients).All patients received EHL at outpatient *** severity was classified by Goligher's *** mean follow-up period was 55.4 mo (range,45-92 mo).RESULTS:The number of band ligations averaged 2.35 in the first session for bleeding and 2.69 for prolapsed *** was controlled in 587 (98.0%) patients,while prolapse was reduced in 137 (82.5%) *** treatment,93 patients experienced anal pain and 48 patients had mild *** subjective satisfaction was 93.6%.Repeat treatment or surgery was performed if symptoms were not relieved in the first *** the bleeding group,the recurrence rate was 3.7% (22 patients) at 1 year,and 6.6%and 13.0% at 2 and 5 *** the prolapsed group,the recurrence rate was 3.0%,9.6% and 16.9% at 1,2 and 5 years,***:EHL is an easy and well-tolerated procedure for the treatment of symptomatic internal hemorrhoids,with good long-term results.

关键词： Bleeding Endoscopy Hemorrhoid Ligation Prolapsed

Improve the Accuracy of Fall Detection Based on Artificial Intelligence Algorithm

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Computer Modeling in Engineering & Sciences 2021年第9期128卷 1103-1119页

作者： ming-Chih chen Yin-Ting cheng Ru-Wei chen Department of Electronic Engineering National Kaohsiung University of Science and Technology(First Campus)Kaohsiung City82445Taiwan

This work presents a fall detection system based on artificial *** system incorporates miniature wearable devices for fall *** detection is achieved by integrating a three-axis gyroscope and a threeaxis *** system gathers the differential data collected by the gyroscope and accelerometer,applies artificial intelligence algorithms for model training and constructs an effective model for fall *** provide easywearing and effective position detection,it is designed as a small device attached to the user’*** results have shown that the accuracy of the proposed fall detection model is up to 98%,demonstrating the effectiveness of the model in real-life fall detection.

关键词： Artificial intelligence fall detection miniature sensing device

A Novel Indoor Positioning Framework

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Computer Modeling in Engineering & Sciences 2022年第3期130卷 1459-1477页

作者： ming-Chih chen Yin-Ting cheng Ru-Wei chen Department of Electronic Engineering National Kaohsiung University of Science and Technology(First Campus)Kaohsiung City82445Taiwan

Current positioning systems are primarily based on the Global Positioning System(GPS).Although the GPS is accurate within 10 m,it is mainly used for outdoor positioning services(Location-Based Service;LBS).However,since satellite signals cannot penetrate buildings,indoor positioning has always been a blind spot for satellite *** indoor positioning applications are extensive with high commercial values,they have created a competitive niche in *** indoor positioning technologies are unable to achieve less than 10 cmaccuracy except for the UltraWide Band(UWB)*** the other hand,the Bluetooth protocol achieves an accuracy of 1 to *** this work,we use Bluetooth wireless signals to build a novel indoor positioning framework to avoid the high manufacturing costs involved in the UWB *** Bluetooth signals are combined with the results from artificial intelligence algorithms to improve *** laboratory indoor location tracking,the accuracy rate is 96%,which provides effective indoor tracking for the movement of people.

关键词： Indoor positioning Bluetooth protocol artificial intelligence

A Task-oriented Modular and Agent-based Collaborative Design Mechanism for Distributed Product Development

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 641-654页

作者： LIU Jinfei chen ming WANG Lei WU Qidi School of Electronics and Information Engineering Tongji University School of Mechanical Engineering Tongji University

The rapid expansion of enterprises makes product collaborative design （PCD） a critical issue under the distributed heterogeneous environment, but as the collaborative task of large-scale network becomes more complicated, neither unified task decomposition and allocation methodology nor Agent-based network management platform can satisfy the increasing demands. In this paper, to meet requirements of PCD for distributed product development, a collaborative design mechanism based on the thought of modularity and the Agent technology is presented. First, the top-down 4-tier process model based on task-oriented modular and Agent is constructed for PCD after analyzing the mapping relationships between requirements and functions in the collaborative design. Second, on basis of sub-task decomposition for PCD based on a mixed method, the mathematic model of task-oriented modular based on multi-objective optimization is established to maximize the module cohesion degree and minimize the module coupling degree, while considering the module executable degree as a restriction. The mathematic model is optimized and simulated by the modified PSO, and the decomposed modules are obtained. Finally, the Agent structure model for collaborative design is put forward, and the optimism matching Agents are selected by using similarity algorithm to implement different task-modules by the integrated reasoning and decision-making mechanism with the behavioral model of collaborative design Agents. With the results of experimental studies for automobile collaborative design, the feasibility and efficiency of this methodology of task-oriented modular and Agent-based collaborative design in the distributed heterogeneous environment are verified. On this basis, an integrative automobile collaborative R＆D platform is developed. This research provides an effective platform for automobile manufacturing enterprises to achieve PCD, and helps to promote product numeralization collaborative R＆D and manag

关键词： collaborative design task-oriented modular multi-agent collaboration mechanism collaborative platform

Numerical Simulation of Peen Forming

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上海交通大学学报 2004年第Z2期38卷 73-78页

作者： Kang Xiaoming Ma Zeen Gu Lin chen ming School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China Department of Aircraft Manufacturing Engineering Northwestern Polytechnical UniversityXi''an710072China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 China

Peen forming is the most important process for the manufacturing of integral wing skin panels. In order to determine peening parameters, an equivalent deformation theory was proposed in which peening parameters are transformed into equivalent nodal forces. In this study, a linear elastic shell finite element method is adopted. Other related problems such as wing skin panel modeling and peening scheme analysis were also outlined. The method has been applied to manufacturing panels of a certain Chinese aircraft and was proved to be effective in reducing peening experimental tests and improving products quality.

关键词： peen forming wing skin panel equivalent deformation theory numerical simulation

Adhesive strength of CVD diamond thin films quantitatively measured by means of the bulge and blister test

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Journal of University of Science and Technology Beijing 2008年第4期15卷 474-479页

作者： Daohui Xiang ming chen Yuping Ma Fanghong Sun School of Mochanical Engineering Shanghai Jiaotong University Shanghai 200240 China School of Mechanical and Power Engineering Henan Polytechnic University Jiaozuo 454000 China

Large advancement has been made in understanding the nucleation and growth of chemical vapor deposition （CVD） diamond, but the adhesion of CVD diamond to substrates is poor and there is no good method for quantitative evaluation of the adhesive strength. The blister test is a potentially powerful tool for characterizing the mechanical properties of diamond films. In this test, pressure was applied on a thin membrane and the out-of-plane deflection of the membrane center was measured. The Young＇s modulus, residual stress, and adhesive strength were simultaneously determined using the load-deflection behavior of a membrane. The free-standing window sample of diamond thin films was fabricated by means of photolithography and anisotropic wet etching. The research indicates that the adhesive strength of diamond thin films is 4.28±0.37 J/m^2. This method uses a simple apparatus, and the fabrication of samples is very easy.

关键词： diamond thin films adhesive strength chemical vapor deposition (CVD) elastic modulus