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Mineralogy, geochemistry and age dating of shear zone-hosted Nb-Ta-, Zr-Hf-, Th-, u-bearing granitic rocks in the Ghadir and El-Sella areas, South Eastern Desert, Egypt

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Chinese Journal Of Geochemistry 2011年第4期30卷 453-478页

作者： Ali M.A. Lentz D.R.2 Nuclear Materials Authority Depatment of geology University of New Brunswick

The rare metal minerals of mineralized altered granites within the Ghadir and El-Sella shear zones, are represented by betafite, u-minerals (uraninite and uranophane), zircon, monazite, xenotime, and rutile in the Ghadir shear zone. While they are columbite-tantalite minerals as ferrocolumbite, pyrochlore, and fergusonite, Th-minerals (cheralite, uranothorite, and huttonite monazite), Hf-zircon, monazite and xenotime in the El-Sella shear zone. Hf-zircon in the El-Sella and Ghadir shear zones (increasing from the core to the rim) contains high inclusions of u-Th, and REE minerals such as cheralite, uranothorite, huttonite monazite and xenotime especially in the El Sella shear zone. The rare-metal minerals, identified from peralkminous granites of the shear zones are associated with muscovite, quartz, chlorite, fluorite, magnetite, and biotite that are restricted to the two shear zones. uraninite (low Th content) occurring in the Ghadir shear zone indicates the hydrothermal origin, but there are thorite, uranothorite, cheralite, and Hf-zircon in the El Sella shear zone, also indicating the hyrothermal proccess after magmatic origin. Compositional variations of Ta/(Ta+Nb) and Mn/(Mn+Fe) in columbite from 0.07-0.42 and 0.04-0.33, respectively, and Hf contents in zircon are so high as to be 12%, especially in the rim in the El Sella shear zone. This feature re-flects the extreme degree of magmatic fractionation. Four samples from the altered granites of the Ghadir shear zone also are very low in TiO2 (0.04 wt%-0.17 wt%), Sr [(82-121)×10-6], and Ba [(36-380)×10-6], but high in Fe2O3T (0.46 wt%-0.68 wt%), CaO (0.64 wt%-1.23 wt%), alkalis (8.59 wt%-8.88 wt%), Rb [(11-203)×10-6], Zr [(98-121)×10-6], Nb [(9-276)×10-6], Ta [(2-139)×10-6], u [(14-63)×10-6], Th [(16-105)×10-6], Pb [(13-32)×10-6], Zn [(7-8)×10-6], Y [(15-138)×10-6], Hf [(3-9)×10-6], and ∑REE [(81-395)×10-6, especially LREE [(70-322)×10-6]. They are very high in Zr/Hf (15.07-85.96) and Nb/Ta (7.17-21.48), and low

关键词：剪切带矿物学花岗岩钽矿物锆石钽铌地球化学蝶

The Time Evolution of Radial Collective Flow in Reaction of ^(197)Au with ^(197)Au at 150 MeV/u

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Chinese journal of nuclear physics 1995年第4期17卷 298-304页

作者： Shen Wen-qing1,2 Xi Hong-fei2,3 A. Gobbi2 N. Herrmann2 K. D. Hildenbrand2 Wang Gao-sheng2 FOPI Collaboration21. CCAST (World Laboratory), P.O. Box 8730, Beijing 100080, and Institute of Nuclear Research, the Chinese Academy of Sciences, P. O. Box 800-204, Shanghai 2018002. Gesellschaft fur Schwerionenforschung, D-64229 Darmstadt, Germany3. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 中科院上海原子核所上海中科院近代物理所甘肃兰州 Gesellschaft fur Schwerionenforschung 德国

Dynamical time evolution for central collision of 197 Au on 197Au at 150 MeV/u is in-vestigated by using Isospin-dependent Quantum Molecular Dynamics （IQMD） calculation. Thepreequilibrium emission, its influence and... 详细信息

Dynamical time evolution for central collision of up>197up> Au on up>197up>Au at 150 MeV/u is in-vestigated by using Isospin-dependent Quantum Molecular Dynamics （IQMD） calculation. Thepreequilibrium emission, its influence and the time evolution of radial collective flow are dis-cussed in detail.

关键词： IQMD simulation Radial collective flow Multifragmentation Dynamical time evolution

Interfacial Morphology and Bonding Mechanism of Explosive Weld Joints

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Chinese Journal of Mechanical Engineering 2021年第2期34卷 201-212页

作者： Tingting Zhang Wenxian Wang zhifeng Yan Jie Zhang Advanced Forming and Intelligent Equipment Research Institute Taiyuan University of TechnologyTaiyuan 030024China College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Interfacial structure greatly affects the mechanical properties of laminated ***,the critical material properties that impact the interfacial morphology,appearance,and associated bonding mechanism of explosive welded plates are still *** this paper,the same base plate(AZ31B alloy)and different flyer metals(aluminum alloy,copper,and stainless steel)were used to investigate interfacial morphology and *** and TEM results showed that typical sine wave,wave-like,and half-wave-like interfaces were found at the bonding interfaces of Al/Mg,Cu/Mg and SS/Mg clad plates,*** different interfacial morphologies were mainly due to the differences in hardness and yield strength between the flyer and base *** results of the microstructural distribution at the bonding interface indicated metallurgical bonding,instead of the commonly believed solid-state bonding,in the explosive welded clad *** addition,the shear strength of the bonding interface of the explosive welded Al/Mg,Cu/Mg and SS/Mg clad plates can reach up to 201.2 MPa,147.8 MPa,and 128.4 MPa,*** proposed research provides the design basis for laminated composite metal plates fabrication by explosive welding technology.

关键词： Interfacial structure Bonding mechanism Explosive welding Metallurgical bonding Magnesium alloy

Theoretical analysis of the convergence property of a basic pigeon-inspired optimizer in a continuous search space

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Science China(Information Sciences) 2019年第7期62卷 90-98页

作者： Yushan ZHANG Han HuANG Hongyue Wu zhifeng HAO School of Statistics and Mathematics Guangdong University of Finance and Economics Big Data and Educational Statistics Application Laboratory Guangdong University of Finance and Economics School of Software Engineering South China University of Technology School of Mathematics and Big Data Foshan University

The pigeon-inspired optimization(PIO) algorithm is a newly presented swarm intelligence optimization algorithm inspired by the homing behavior of pigeons. Although PIO has demonstrated effectiveness and superiority in numerous fields, particularly in practical engineering optimization, there have been few results concerning the theoretical foundations of PIO. This paper conducts convergence analysis of basic PIO in a continuous search space in two aspects. First, we analyze the convergence of each pigeon’s expected position using a difference equation and prove that the average position of each pigeon in the swarm will converge to the same value. To further study the stochastic global convergence property of the pigeon swarm, we apply the martingale theory to investigate the basic PIO swarm sequence, and achieve a sufficient condition to guarantee global convergence of the basic PIO. Our theoretical analysis shows that this convergence depends upon the accumulation of the minimum probability with which the pigeon swarm jumps to the global-optimal region at each iteration. The mathematical methods proposed in this study, particularly the martingale technique, also provide a new effective approach for the theoretical analysis of bio-inspired algorithms in continuous optimization.

关键词： pigeon-inspired optimization(PIO) convergence analysis martingale continuous optimization swarm intelligence

A GLCM-Feature-Based Approach for Reversible Image Transformation

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Computers, Materials & Continua 2019年第4期59卷 239-255页

作者： Xianyi Chen Haidong Zhong zhifeng Bao School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Jiangsu Engineering Centre of Network Monitoring Nanjing210044China School of Computer Science and Information Technology RMIT UniversityMelbourneAustralia

Recently,a reversible image transformation(RIT)technology that transforms a secret image to a freely-selected target image is *** not only can generate a stego-image that looks similar to the target image,but also can recover the secret image without any *** also has been proved to be very useful in image content protection and reversible data hiding in encrypted ***,the standard deviation(SD)is selected as the only feature during the matching of the secret and target image blocks in RIT methods,the matching result is not so good and needs to be further improved since the distributions of SDs of the two images may be not very ***,this paper proposes a Gray level co-occurrence matrix(GLCM)based approach for reversible image transformation,in which,an effective feature extraction algorithm is utilized to increase the accuracy of blocks matching for improving the visual quality of transformed image,while the auxiliary information,which is utilized to record the transformation parameters,is not ***,the visual quality of the stego-image should be *** results also show that the root mean square of stego-image can be reduced by 4.24%compared with the previous method.

关键词： Image encryption feature extraction reversible image transformation GLCM

An automatic docking method for large-scale sections based on real-time pose measuring and assembly deviation control

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Optoelectronics Letters 2023年第11期19卷 686-692页

作者： QIAO zhifeng Fu Kang LIu Zhenzhong Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin300384China

Aiming at the problem of poor accuracy consistency of large sections’docking assembly,an automatic docking method using multiple laser trackers to measure the position and posture of the docking sections in real time was *** the solution of the pose of the docking section,real-time pose measurement of the docking section was realized by establishing a global coordinate system and a coordinate fusion method of three or more laser *** the automatic control of the docking process,the real-time communication protocol and the circular negative feedback control strategy of measurement-adjustment-re-measurement are adopted,and the fully-automated docking of large sections is ***,an experimental verification system was set up,and the docking of the large-scale section reduction models was realized under the requirements of docking accuracy,and the effectiveness of the automatic docking scheme was successfully verified.

关键词： coordinate deviation system

Exploring serverless computing for stream analytic

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High Technology Letters 2020年第1期26卷 17-24页

作者： Cheng Yingchao Hao zhifeng Cai Ruichu School of Computer Science and Technology Guangdong University of TechnologyGuangzhou 510006P.R.China School of Mathematics and Big Data Foshan UniversityFoshan 528000P.R.China Department of Statistics Texas A&M UniversityCollege Station 77840USA

This work proposes ARS(FaaS) serverless framework scheduling and provisioning resources for streaming applications autonomously, which ensures real-time response on unpredictable and fluctuating streaming data. A HPC cloud platform is used as a de facto platform, on which serverless computing for stream analytic is explored. This work enables application developers to build and run steaming applications without worrying about servers, which means that the developers are able to focus on application features instead of scheduling and provisioning resources of the infrastructure. The serverless computing framework, ARS(FaaS), provides function-as-a-service to make the developers write code in discrete event-driven functions. ARS(FaaS) is capable of running and scaling the developer's code automatically, according to the throughput of streaming events. The major contribution of this serverless framework is effective and efficient autonomous resource scheduling for real-time streaming analytic, which enables the developers to build applications faster with autonomous resource scheduling. ARS(FaaS) framework is appropriate for real-time and stream analytic on event-driven data with spiky and variable compute requirements.

关键词： serverless steam processing HPC cloud auto-scaling function-as-a-service(FaaS)

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基于消息相似度的拜占庭容错共识算法

指挥与控制学报 2024年第4期10卷 479-490页

作者：任志丰胡华平容英耀吴维刚卞静中山大学计算机学院广州510006 国防科技大学计算机学院长沙410073

为保证入侵容忍的数据可用性和可靠性,区块链系统需要使用拜占庭容错算法对数据进行复制备份,以避免受被入侵节点攻击而导致的数据不可用,甚至数据丢失。针对Quorum模式拜占庭容错算法,提出了在高并发场景下实现平滑降级的Q/u-GD算法,... 详细信息

为保证入侵容忍的数据可用性和可靠性,区块链系统需要使用拜占庭容错算法对数据进行复制备份,以避免受被入侵节点攻击而导致的数据不可用,甚至数据丢失。针对Quorum模式拜占庭容错算法,提出了在高并发场景下实现平滑降级的Q/u-GD算法,该算法使用消息相似度机制来对Q/u算法进行优化。设计的消息相似度机制通过提升客户端和副本节点接受的消息的相似度,减少触发不必要的修复操作,实现性能平滑降级。实验结果表明,Q/u-GD算法的吞吐量在高并发场景下降级平缓,且明显高于Q/u算法。

关键词：拜占庭容错区块链可用性可靠性 Quorum模式

Human leukocyte antigen compatibility and incidence of donorspecific antibodies in pediatric liver transplant recipients

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World Journal of Gastroenterology 2024年第33期30卷 3837-3845页

作者： Melina u Melere Flavia H Feier Jorge Neumann Antônio N Kalil Juliana de M Montagner Luiza S Nader Carolina S da Silva Marco Aurélio F Junior Gabriela P Coral Guilherme P Bobsin Cristina T Ferreira Department of Hepatology and Liver Transplantation Santa Casa de Porto AlegrePorto Alegre 90050170Rio Grande do SulBrazil Department of Hepato-biliary-pancreatic Surgery and Liver Transplantation Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil Postgraduation Program in Medicine:Hepatology Federal University of Health Sciences of Porto AlegrePorto Alegre 90050-170Rio Grande do SulBrazil Laboratory of Transplantation Immunology Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil

BACKGROuND Antibody-mediated rejection following liver transplantation(LT)has been increasingly recognized,particularly with respect to the emergence of de novo donor-specific antibodies(DSAs)and their impact on graft *** substantial evidence for adult populations exists,research focusing on pediatric LT outcomes remains *** To investigate the prevalence of human leukocyte antigen(HLA)mismatches and DSA and evaluate their association with rejection episodes after pediatric *** A cohort of pediatric LT recipients underwent HLA testing at Santa Casa de Porto Alegre,Brazil,between December 2013 and December *** patients who survived for>30 days after LT with at least one DSA analysis were *** classes I and II and cross-matches were *** presence of de novo DSA(dnDSA)was evaluated at least 3 months after LT using the Luminex®single antigen bead method,with a positive reaction threshold set at 1000 *** episodes were confirmed by liver *** Overall,67 transplanted children were analyzed;61 received grafts from living donors,85%of whom were related to ***-transplant DSA(class I or II)was detected in 28.3%of patients,and dnDSA was detected in 48.4%.The median time to DSA detection after LT was 19.7[interquartile range(IQR):4.3-35.6]*** rejection occurred in 13 patients at follow-up,with C4d positivity observed in 5/13 Liver *** median time to rejection was 7.8(IQR:5.7-12.8)*** presence of dnDSA was significantly associated with rejection(36%vs 3%,Purvival rates at 12 and 24 months were 76%vs 100%and 58%vs 95%for patients with dnDSA anti-DQ vs those without,*** Our findings highlight the importance of incorporating DSA assessment into pre-and post-transplantation protocols for pediatric LT *** implications may include immunosuppression minimization strategies based on this analysis in pediatric LT recip

关键词： Human leukocyte antigens Donor-specific antibodies Liver transplantation Pediatric Rejection