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塔里木盆地西北缘早寒武世玉尔吐斯组硅质岩成因

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西北大学学报（自然科学版） 2024年第4期54卷 715-728页

作者：曹旭阳韩以贵鞠鹏程鲁立辉邵东石震西北大学地质学系/大陆动力学国家重点实验室陕西西安710069 中国科学技术大学地球和空间科学学院/中国科学院壳幔物质与环境重点实验室安徽合肥230026

对塔里木盆地西北缘下寒武统玉尔吐斯组硅质岩开展岩石学以及元素与硅同位素地球化学研究,探讨硅质岩的成因及沉积模式。岩石学观察表明,玉尔吐斯组中段硅质岩主要由隐晶硅质和微晶石英组成,未见碎屑石英,排除了陆源输入对硅质岩沉积的... 详细信息

对塔里木盆地西北缘下寒武统玉尔吐斯组硅质岩开展岩石学以及元素与硅同位素地球化学研究,探讨硅质岩的成因及沉积模式。岩石学观察表明,玉尔吐斯组中段硅质岩主要由隐晶硅质和微晶石英组成,未见碎屑石英,排除了陆源输入对硅质岩沉积的影响。玉尔吐斯组下段硅质岩相对富Fe且具有显著的Eu正异常,反映了硅质岩可能主要来源于海底热液;而中段硅质岩显示Y/Ho比值较高、中等Ce负异常、LREE亏损和Y正异常,说明硅质来源主要为海水,这也符合中段硅质岩具有总体偏向热水来源的δ^(30)Si值。此外,氧化还原敏感元素指标表明,玉尔吐斯组硅质岩的沉积环境为表层海水氧化,而底层海水缺氧甚至硫化。研究认为,玉尔吐斯组硅质岩的沉积模式为:下段硅质岩由大量富硅热液在上升流作用下直接沉积,之后热液活动减弱,氧化还原分层海洋促进海水中溶解的硅和铁循环耦合,硅质以Fe^(3+)-Si胶体形式共沉积,当硫化水域盛行时铁和硅循环解耦,沉积黑色页岩,形成中段硅质岩和黑色页岩互层。

关键词：塔里木盆地早寒武世玉尔吐斯组硅质岩沉积环境

Near-surface absorption compensation technology and its application in the Daqing Oilfields

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Applied Geophysics 2009年第2期6卷 184-191页

作者： Shi Zhanjie Tian Gang Wang Bangbing chert Shumin Department of Earth Sciences Zhejiang University Hangzhou 310027 China Exploration and Development Research Institute of Daqing Oilfield Co. Ltd. Daqing 163712 China

高周波的地震数据部件能严重在 unconsolidated 在震波繁殖期间被稀释(低速度) 层，导致减少的地震分辨率和 signal-to-noise (S/N ) 比率。在这篇论文，基于维纳过滤器理论，首先，为近表面的吸收变细赔偿的反的过滤器计算被直接波浪... 详细信息

高周波的地震数据部件能严重在 unconsolidated 在震波繁殖期间被稀释(低速度) 层，导致减少的地震分辨率和 signal-to-noise (S/N ) 比率。在这篇论文，基于维纳过滤器理论，首先，为近表面的吸收变细赔偿的反的过滤器计算被直接波浪的分析完成光谱从不同距离的部件接近表面。直接波浪被雷管产生在在洞射击上面并且被接收装置在表面上获得。空间地变化的反的过滤器被设计补偿因为 3D 的频率变细预先叠 CRG (普通接收装置集合) 数据。在把过滤器用于 CRG 数据以后，高频率部件被补偿，低频率维持了。地震决定和 S/N 比率与合成震动图更好被提高并且匹配并且更好满足地质的解释的需要。

关键词：补偿技术吸收衰减近地表大庆油田应用地震波传播合成地震记录光谱成分

A MULTI-COUPLED FINITE ELEMENT ANALYSIS OF RESISTANCE SPOT WELDING PROCESS

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Acta Mechanica Solida Sinica 2006年第1期19卷 86-94页

作者： Hou Zhigang Wang Yuanxun Li Chunzhi chert Chuanyao School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China School of Mechtronic and Automobile Engineering Yantai University Yantai 264005 China

A two-dimensional axisymmetric finite element model is developed to analyze the transient thermal and mechanical behaviors of the Resistance Spot Welding （RSW） process using commercial software ANSYS. Firstly a direct-coupled electrical-thermal Finite Element Analysis （FEA） is performed to analyze the transient thermal characteristics of the RSW process. Then based on the thermal results a sequential coupled thermo-elastic-plastic analysis is conducted to determine the mechanical features of the RSW process. The thermal history of the whole process and the temperature distribution of the weldment are obtained through the analysis. The mechanical features, including the distributions of the contact pressure at both the faying surface and the electrode-workpiece interface, the stress and strain distributions in the weldment and their changes during the RSW process, the deformation of the weldment and the electrode displacement are also calculated.

关键词： Finite Element Analysis (FEA) Resistance Spot Welding (RSW) electrical-thermal coupling thermo-elastic-plastic analysis thermal behavior mechanical feature

Development of Ag-Cu-Zn-Sn brazing filler metals with a 10 weight-% reduction of silver and same liquidus temperature

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China Welding 2014年第4期23卷 25-31页

作者： Daniel Schnee Gunther Wiehl Sebastian Starck chert kevin Umicore AG & Co. KG Business Unit Technical MaterialsRodenbacher Chaussee 4 63457 Hanau-Wolfgang Germany.

With BrazeTec BlueBraze the manufacturers in HVACR industry have an alternative filler metal with 10 weight-% less silver but same brazing temperatures. The performance of these new alloys has been evaluated in several tests. The evaluation included wetting investigations, metallographic examinations, joint strength at different temperatures and pulsation and corrosion resistance. The results of these tests will be presented in this paper.

关键词： silver brazing filler metal shear strength corrosion

xBreeze/ADL:A Language for Software Architecture Specification and Analysis

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International Journal of Automation and computing 2016年第6期13卷 552-564页

作者： chert Li Hong-Ji Yang Mei-Yu Shi Wei Zhu School of Humanities and Cultural Industries Bath Spa UniversityUK Tourism Institute Beijing Union UniversityBeijing 100101China

Architecture description languages play an important role in modelling software architectures. However, many architecture description languages （ADLs） are either unable to deal with the verification and dynamic changes directly or too formal to be understood and manipulated. This paper presents xBreeze/ADL, a novel extensible markup language （XML）-based verification and evolution supported architecture description language, which is specifically designed for modelling the software architecture of large, complex systems. Five principle design goals are 1） to separate template from instance to define a loose coupling structure, 2） to present virtual and concrete link to identify service execution flow, 3） to clearly represent component behaviour to specify architecture semantics, 4） to introduce multi-dimension restrictions to define the architecture constraints, and 5） to use the graph transformation theory to implement the architecture configuration management （i.e., reconfiguration and verification）. Various advanced features of xBreeze/ADL are illustrated by using an example on online movie ticket booking system.

关键词： Software architecture architecture description language (ADL) xBreeze/ADL breeze graph grammar Breeze/ADL.

A DISTRIBUTED COOPERATIVE RELAYING OPTIMIZATION SCHEME FOR SECONDARY TRANSMISSION IN COGNITIVE RADIO NETWORKS

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Journal of Electronics(China) 2011年第1期28卷 8-14页

作者： chert Dan Ji Hong key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In Cognitive Radio(CR) networks,cooperative communication has been recently regarded as a key technology for improving the spectral utilization efficiency and ensuring the Quality of Service(QoS) for Primary Users(PUs).In this paper,we propose a distributed joint relay selection and power allocation scheme for cooperative secondary transmission,taking both Instantaneous Channel State Information(I-CSI) and residual energy into consideration,where secondary source and destination may have different available ***,we formulate the cognitive relay network as a restless bandit system,where the channel and energy state transition is characterized by the finite-state Markov *** proposed policy has indexability property that dramatically reduces the computation and implementation *** and simulation results demonstrate that our proposed scheme can efficiently enhance overall system reward,while guaranteeing a good tradeoff between achievable date rate and average network lifetime.

关键词： Cognitive Radio(CR) Secondary transmission Relay selection Power allocation Restless bandit system

A Novel Fuzzy Direct Torque Control System for Three-level Inverter-fed Induction Machine

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International Journal of Automation and computing 2010年第1期7卷 78-85页

作者： Shu-Xi Liu Ming-Yu Wang Yu-Guang chert Shan Li State key Laboratory of Power Transmission Equipment % Systems Security and New Technology Chongqing University Chongqing 400044 PRC School of Electronic Information and Automation Chongqing University of Technology Chongqing 400050 PRC

Diode clamped multi-level inverter （DCMLI） has a wide application prospect in high-voltage and adjustable speed drive systems due to its low stress on switching devices, low harmonic output, and simple structure. However, the problem of complexity of selecting vectors and capacitor voltage unbalance needs to be solved when the algorithm of direct torque control （DTC） is implemented on DCMLI. In this paper, a fuzzy DTC system of an induction machine fed by a three-level neutral-point-clamped （NPC） inverter is proposed. After introducing fuzzy logic, optimal selecting switching state is realized by applying various strategies which can distinguish the grade of the errors of stator flux linkage, torque, the neutral-point potential, and the position of stator flux linkage. Consequently, the neutral-point potential unbalance, the dr/dr of output voltage and the switching loss are restrained effectively, and desirable dynamic and steady-state performances of induction machines can be obtained for the DTC scheme. A design method of the fuzzy controller is introduced in detail, and the relevant simulation and experimental results have verified the feasibility of the proposed control algorithm.

关键词： Multi-level inverter direct torque control (DTC) fuzzy controller space voltage vector induction machine

A preliminary study on genesis of the Qiongzhou Straits

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Acta Oceanologica Sinica 1989年第1期8卷 113-123页

作者： Zhang Hunan and chert Weiguang Guangdong Bureau of Seismology, Guangzhou, China Guangdong Bureau of Seismology Guangzhou China China

The active period of the faults in the Qiongzhou Straits occurred principally in the Tertiary. The rupture zone is situated in the nearly E-W striking tectonic lowland between the Leizhou Peninsula and the Hainan Island, which was preformed by the southward and northward compressions due to the expansion of the South China Sea Basin. During the interglacial periods in the Quaternary, the lowland was inundated and deepened gradually due to erosion by sea curfent. It was until the last uprising of sea level during the postglacial period that the Qiongzhou Straits assumed its present appearance.

关键词： A preliminary study on genesis of the Qiongzhou Straits

Fuberculosis of Lymph Node Combined with Pulmonary Mucormycosis

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Chinese Medical Journal 2015年第20期 2812-2814页

作者： Shan Yu Hong-Bing chert No. 4 Department of Tuberculosis No. 309 Hospital of PLA Beijing 100091 China

Mucormycosis is a life-threatening fungal infection which often occurs in patients with underlying disease, and often resulting in a fatal outcome due to the difficulty of early diagnosis and its resistance to antimycotics. Tuberculosis （TB） of lymph node combined with pulmonary muconnycosis is rare. In this article, we reported a case of TB of mediastinal lymph node combined with pulmonary mucormycosis that was presented as obstructive pneumonia combined with lymphoma.

关键词： lmmunocompetence Lung: Mucormycosis Tuberculosis