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Study of the closure temperature of(U-Th)/He in detrital zircon obtained from natural evolution samples

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Science China Earth Sciences 2020年第3期63卷 412-424页

作者： chang'e cai Nansheng QIU Huili LI Daniel FSTOCKLI Jian chang Nian LIU State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development Chongqing University of Science and TechnologyChongqing 401331China Institute of Petroleum Exploration and Development Northwest Oil CompanySINOPECUrumqi 830011China Jackson School of Geosciences The University of Texas at AustinAustinTX 78712USA

Zircon(U-Th)/He thermochronometry was used as an effective indicator to study the thermal history of deep sedimentary basins with high *** He ages and closure temperatures are very important *** this paper,detrital zircon He closure temperature was studied by establishing the evolutionary pattern between zircon He ages and burial depth of borehole samples obtained from the Cenozoic strata in the Bohai Bay and Tarim basins,which have different thermal *** results show that the zircon He closure temperature of natural evolution samples is 200℃,which is higher than the temperature obtained from thermal simulation experiments(183℃).The temperature range of 140-200℃corresponds to the zircon helium partial retention *** properly understanding zircon He closure temperatures,zircon(U-Th)/He thermochronometry can provide a correct explanation of the He ages,and significant guidance in the study of the evolution of source rocks and the process of hydrocarbon accumulation in deep sedimentary basins.

关键词： Zircon(U-Th)/He Natural evolution sample Closure temperature Partial retention zone

RIS-Aided Constant-Envelope Beamforming for Multiuser Wireless Power Transfer:A Max-Min Approach

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China Communications 2021年第3期18卷 80-90页

作者： Huiyuan Yang chang cai Xiaojun Yuan Yingchang Liang Center for Intelligent Networking and Communications University of Electronic Science and Technology of ChinaChengdu 611731China

As a revolutionary hardware technology that can reconfigure the propagation environment,reconfigurable intelligent surfaces(RISs)have been regarded as a promising solution to enhance wireless *** this paper,we consider a multiuser multiple-input single-output(MISO)wireless power transfer(WPT)system,which is assisted by several *** order to improve energy efficiency and reduce hardware cost,we consider that the energy transmitter(ET)in the WPT system is equipped with a constant-envelope analog beamformer,instead of a digital *** on user fairness,we study a minimum received power maximization problem by jointly optimizing the ET beamforming and the RIS phase shifts,subject to the constant-envelope *** iteratively solve this non-convex maxmin problem by leveraging both the successive convex approximation(SCA)method and the alternating direction method of multipliers(ADMM)*** results demonstrate the effectiveness of the proposed algorithm and show attractive performance gain brought by RISs.

关键词： reconfigurable intelligent surface wireless power transfer max-min fairness constantenvelope beamforming

Detection Algorithm of Knee Osteoarthritis Based on Magnetic Resonance Images

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Intelligent Automation & Soft Computing 2023年第7期37卷 221-234页

作者： Xin Wang Shuang Liu chang-cai Zhou College of Computers Science and Engineering Changchun University of TechnologyChangchun130000China

Knee osteoarthritis(OA)is a common disease that impairs knee function and causes ***,studies on the detection of knee OA mainly focus on X-ray images,but X-ray images are insensitive to the changes in knee OA in the early *** magnetic resonance(MR)imaging can observe the early features of knee OA,the knee OA detection algorithm based on MR image is innovatively proposed to judge whether knee OA is ***,the knee MR images are preprocessed before training,including a region of interest clipping,slice selection,and data *** the data set was divided by patient-level and the knee OA was classified by the deep transfer learning method based on the DenseNet201 *** method divides the training process into two *** first stage freezes all the base layers and only trains the weights of the embedding neural *** second stage unfreezes part of the base layers and trains the unfrozen base layers and the weights of the embedding neural *** this step,we design a block-by-block fine-tuning strategy for training based on the dense blocks,which improves detection *** have conducted training experiments with different depth modules,and the experimental results show that gradually adding more dense blocks in the fine-tuning can make the model obtain better detection performance than only training the embedded neural network *** achieve an accuracy of 0.921,a sensitivity of 0.960,a precision of 0.885,a specificity of 0.891,an F1-Score of 0.912,and an MCC of *** comparative experimental results on the OAI-ZIB dataset show that the proposed method outperforms the other detection methods with the accuracy of 92.1%.

关键词： Knee joint osteoarthritis magnetic resonance images two-stage transfer learning DenseNet201

Thermal Annealing Characteristics of Detrital Zircon Fission Track Obtained from Natural Borehole Samples

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Journal of Earth Science 2022年第1期33卷 45-56页

作者： chang'e cai Nansheng Qiu Jian chang Cleber Jose Soares Hong Chen Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development Chongqing University of Science and TechnologyChongqing 401331China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China ChronusCamp Research-Thermochronology Analyses LTD Itapira 13974Brazil

Previous studies proposed thermal simulation experiment to investigate the annealing characteristics of fission tracks in igneous zircon ***,basic research about detrital zircon fission track was relatively *** study discussed the initial track length,annealing temperature and annealing model of zircon fission track by using the measured track lengths obtained from natural borehole samples in the sedimentary basins with different thermal *** results show that the initial track length of zircon fission track is 12.97 μ*** total annealing temperature(Ttotal) of zircon fission track derived from the evolutionary curve of the mean track lengths is approximately 400 ℃.The temperature ranges of 120-230 ℃ corresponds to the partial annealing zone(PAZ),and is lower than the range obtained through thermal annealing *** annealing model is modified based on the measured track *** addition,a functional formula about the mean track length,annealing temperature,and geological time is proposed,and the fitted values of track lengths consist with the measured track lengths in this *** properly understanding the initial track length and annealing behavior of zircon fission track can provide a significant guidance for the study of hydrocarbon accumulation in sedimentary basins.

关键词： zircon detrital zircon fission track initial track length annealing temperature annealing model natural borehole sample

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A Review on Modeling of Bionic Flow Control Methods for Large-Scale Wind Turbine Blades

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Journal of Thermal Science 2021年第3期30卷 743-757页

作者： ZHANG Mingming ZHANG Yi’nan cai chang CAO Huijing ZHANG Ziliang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Wind Energy Utilization Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory For Clean energy Chinese Academy of SciencesDalian 116023China Institute of Science and Technology China Three Gorges CorporationBeijing 100038China

Due to complicated working conditions,the normal operating large-scale wind turbine blades are often suffering from some inevitable problems,i.e.,friction adhesion,flow separation and acoustic noise,which may significantly affect the aerodynamic performance of the blades and thus the wind turbine ***,effective measurements must be taken to solve these ***,several novel bionic flow control methods by mimicking shark skin,whale fin and owl wing,i.e.,riblet,leading-edge protuberance and trailing-edge serration,have been recently studied,and good progresses have been made in terms of effectiveness,analysis and ***,these potential techniques are unable to be widely applied within wind energy community due to the lack of reasonable modeling methods,clearly reflecting the effect of bionic structures on the flow field around,which results in incapability to carry out further optimal design of bionic *** this end,this review paper first concentrated on a summary of the control mechanisms of three bionic *** on this,some feasible ideas of model buildup were ***,the flow analyses around the typical blade airfoils were chosen as case studies to verify the feasibility and accuracy of these simulation methods.

关键词： riblets leading-edge protuberances trailing-edge serrations modeling method

Generalized Harmonic Oscillator and the Schrdinger Equation with Position-Dependent Mass

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Communications in Theoretical Physics 2009年第5期51卷 797-802页

作者： JU Guo-Xing cai chang-Ying REN Zhong-Zhou Department of Physics Nanjing University Nanjing 210093 China Department of Physics Jinggangshan University Ji＇an 343009 China

We study the generalized harmonic oscillator that has both the position-dependent mass and the potential depending on the form of mass function in a more general framework. The explicit expressions of the eigenvalue and eigenfunction for such a system are given, they have the same forms as those for the usual harmonic oscillator with constant mass. The coherent state and its properties corresponding effective potentials for several mass functions, for the system with PDM are also discussed. We give the the systems with such potentials are isospectral to the usual harmonic oscillator.

关键词： generalized harmonic oscillator Schr6dinger equation position-dependent mass coherent state

Distribution laws of abutment pressure around fully mechanized top-coal caving face by in-situ measurement

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Journal of Coal Science & Engineering(China) 2011年第1期17卷 1-5页

作者： chang Ju-cai The Key Laboratory of Safe and Highefficieney Mining of Ministry of Education Anhui University of Science and Technology Huainan 232001 China

In order to obtain the distribution rules of abutment pressure around the 1151 （3） fully mechanized top-coal caving （FMTC） face of Xieqiao Colliery, the KSE-II-1 type bore-hole stress gauges were installed in the tailentry and headentry to measure the mining-induced stress. The distribution rules of the front and side abutment pressure were demonstrated. The results show that distribution rules of stress are obviously different in the vicinity of the face and entries. The peak value of abutment pressure in the protective coal pillar and face are located commonly in front of the working face along the strike, and they are located at the stress-decreased zone near the face. There is no stress peak value in the lateral coal mass beside the headentry in front of the face on the strike, and the peak value of abutment pressure appears at the rear area of the face. There are stress peak values both in the protective coal pillar and in the lateral coal mass beside the headentry to the dip.

关键词： fully mechanized top-coal caving face abutment pressure in-situ measurement

Wind Tunnel Experiments and Numerical Study on Performance Characteristics of an H-type Vertical Axis Wind Turbine in the Spanwise Direction

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Journal of Thermal Science 2021年第3期30卷 758-771页

作者： ZHANG Yanfeng LI Qing’an ZHU Xinyu SONG Xiaowen cai chang GUO Zhiping College of Science Inner Mongolia University of TechnologyHohhot 010051China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China College of Mechanical Engineering Inner Mongolia University of TechnologyHohhot 010051China

The aerodynamic forces and vortex characteristics of an H-type Vertical Axis Wind Turbine(VAWT)become complicated because of dynamic stall,particularly in the three-dimensional impact on the blade spanwise *** study focused on the evaluation of the aerodynamic performance and vortex characteristics of an H-type VAWT in the spanwise direction by numerical simulations and wind tunnel *** acting on the blade surface was obtained from multiport pressure measurement devices by wind ***,the vortex field around different blade sections was investigated through numerical *** stall behavior was analysed by comparing the results of numerical simulations and *** a result,the tangential force of single blade was mainly contributed at the chordwise position of x/c≤0.4 c and the power of single blade was mainly contributed at the azimuthal angle range of 60°≤θ≤150°in the blade section position region of 0≤z/(H/2)≤*** the section position of z/(H/2)=0.5,the initial flow separation was found at the suction side and progressed forward to the leading *** the increase of the tip speed ratios,the decreasing position of the averaged local power coefficient of each section was closer to the middle section of z/(H/2)=0,and the attenuation speed became *** power coefficient reductions at the blade section position of z/(H/2)=0.9 were 38.29%,46.78%and 56.42%when the tip speed ratios were 1.38,2.19 and 2.58,*** results of this study provided a better understanding of the development of the performance characteristics and vortex characteristics of H-type VAWT.

关键词： VAWT wind tunnel experiments CFD spanwise direction pressure distribution power coefficient

Mechanical Analysis of Dead Load Crown and Structure Parameter of Hydraulic Elastic Bulging Roll

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Journal of Iron and Steel Research International 2003年第3期10卷 28-31页

作者： ZHAO chang-cai LI Wei-min LIU Zhu-bai Yanshan University

The dead load crown of hydraulic elastic bulging roll was discussed using the theory of elastically supported beam,and the dead load experiment was carried out. The theoretical calculation is consistent with the experimental result. The structure parameters for the thickness of roll sleeve,the length of the oil groove and the crown of roll were discussed. The fundamental principle of determining the parameters was put forward. The theoretical basis of the application of the hydraulic elastic bulging roll was established.

关键词： hydraulic elastic bulging roll bulging crown dead load