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Dislocation Dissociation Strongly Influences on Frank-Read Source Nucleation and Microplasticy of Materials with Low Stacking Fault Energy

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Chinese Physics Letters 2014年第4期31卷 96-99页

作者： huang Min-sheng Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment Wuhan 430074

The influence of dislocation dissociation on the evolution of Frank-Read （F-R） sources is studied using a three- dimensional discrete dislocation dynamics simulation （3D-DDD）. The classical Orowan nucleation stress and recently proposed Benzerga nucleation time models for F-R sources are improved. This work shows that it is necessary to introduce the dislocation dissociation scheme into 3D-DDD simulation, especially for simulations on micro-plasticity of small sized materials with low stacking fault energy.

关键词： NUCLEATION MOLECULAR dynamics DISLOCATION loops DISSOCIATION (Chemistry) NICKEL

Transmission success probability analysis of vehicle users with mobile relays under mobility models

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Science China(Information Sciences) 2020年第6期63卷 250-252页

作者： Di WU sheng huang College of Pharmacy and Biological Engineering Chengdu University No.10 Institute of China Electronic Technology Corporation

Dear editor,Mobile relays have been proposed to solve the challenges of capacity boost, coverage extension,and group mobility in the long-term-evolution advanced standard (LTE-A)[1]. A mobile relay inside a public vehicle can receive signals from an eNodeB via external antennas and forward the signals to vehicle user equipments (VUEs) through an internal antenna in the public vehicle. Because public vehicles are usually well shielded with

关键词： Nakagami Transmission success probability analysis of vehicle users with mobile relays under mobility models eNodeB

Efficient parallel adaptive array beamforming algorithm

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1221-1226页

作者： huang Fei sheng Weixing Ma Xiaofeng Dept. of Communication Engineering Nanjing Univ. of Science and Technology Nanjing 210094 P. R. China

For a large-scale adaptive array, the heavy computational load and the high-rate data transmission are two challenges in the implementation of an adaptive digital beamforming system. An efficient parallel digital beamforming （DBF） algorithm based on the least mean square algorithm （PLMS） is proposed. An appropriate method is found to partition the least mean square （LMS） algorithm into a number of operational modules, which can be easily executed in a distributed-parallel-processing fashion. As a result, the proposed PLMS algorithm provides an effective solution that can alleviate the bottleneck of high-rate data transmission and reduce the computational cost. PLMS requires less computational load than that of the conventional parallel algorithms based on the recursive least square （RLS） algorithm, as well as it is easier to be implemented to do real time adaptive array processing. Moreover, low sidelobe of the beam pattern is obtained by constraining the static steering vector with Tschebyscheff coefficients. Finally, a scheme of the PLMS algorithm using distributed-parallel-processing system is also proposed. The simulation results demonstrate that the PLMS algorithm has the same interference cancellation performance as that of the conventional LMS algorithm. Moreover, the PLMS algorithm can obtain the same good beamforming performance, regardless how the algorithm is partitioned. It is expected that the proposed algorithm will be used in a large-scale adaptive array system to deal with real time adaptive digital beamforming processing.

关键词： adaptive digital beamforming parallel algorithm least mean square generalized sidelobe canceller.

Photometric redshifts of galaxies from SDSS and 2MASS

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 390-400页

作者： Tao Wang Jia-sheng huang Qiu-sheng Gu Department of Astronomy Nanjing University Nanjing 210093 China Harvard-Smithsonian Center for Astrophysics 60 Garden Street Cambridge MA 02138

In order to find the physical parameters which determine the accuracy of pho- tometric redshifts, we compare the spectroscopic and photometric redshifts （photo-z＇s） for a large sample of -80000 SDSS-2MASS galaxies. Photo-z＇s in this paper are estimated by using the artificial neural network photometric redshift method （ANNz）. For a subset of -40000 randomly selected galaxies, we find that the photometric redshift recovers the spectroscopic redshift distribution very well with rms of 0.016. Our main results are as follows：（1） Using magnitudes directly as input parameters produces more accurate photo-z＇s than using colors; （2） The inclusion of 2MASS （J, H, Ks） bands does not improve photo-z＇s significantly, which indicates that near infrared data might not be important for the low-redshift sample; （3） Adding the concentration index （essentially the steepness of the galaxy brightness profile） as an extra input can improve the photo-z＇s estimation up to -10 percent; （4） Dividing the sample into early- and late-type galaxies by using the concentration index, normal and abnormal galaxies by using the emission line flux ratios, and red and blue galaxies by using color index （g - r）, we can improve the accuracy of photo-z＇s significantly; （5） Our analysis shows that the outliers （where there is a big difference between the spectroscopic and photometric redshifts） are mainly correlated with galaxy types, e.g., most outliers are late-type （blue） galaxies.

关键词： galaxies distances and redshifts-methods statistical-techniques pho-tometric

Interference management for rate-constrained moving relay node in a heterogeneous network

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Science China(Information Sciences) 2014年第10期57卷 34-45页

作者： huang sheng LI JianDong ZHAO LinJing huang JinJing Broadband Wireless Communications Laboratory Information Science InstituteState Key Laboratory of ISN Xidian University

Cooperative communication via a moving relay node(MRN) helps resolve both the poor quality of service(QoS) and limited battery-capacity problems of cell-edge vehicle user equipment(VUE). This paper investigates the performance of MRNs in a heterogeneous network(HetNet). MRNs as well as other small cells are expected to coexist in a complex manner. In such a HetNet, the inter-cell interference may degrade the expected improvement of MRNs, especially at the cell-edge. In this paper, we investigate the impact of intercell interference on the performance of MRNs. To alleviate this impact, we first formulated a general optimization problem for which it is intractable to find a global optimal solution. To have a practical solution with low computational complexity, we used a practical interference management algorithm that aimed to ensure that every MRN achieved its required minimum-rate while maximizing total network throughput. In the simulations, the proposed algorithm was observed to improve both the QoS and fairness of MRNs. Numerical results demonstrate that the proposed algorithm can offer an efficient trade-off between the performance of both the victim MRNs and aggressing femtocells.

关键词： moving relay node minimum-rate constraint heterogeneous network inter-cell interference sub-channel allocation interference mitigation

Microstructure and Mechanical Properties of B-Bearing Austenitic Stainless Steel Fabricated by Laser Metal Deposition In-Situ Alloying

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Acta Metallurgica Sinica(English Letters) 2022年第3期35卷 453-465页

作者： sheng huang Xiaoyu Zhang Dichen Li Qingyu Li State Key Laboratory for Manufacturing Systems Engineering Xian Jiaotong UniversityXian 710049China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

In the field repair application of laser metal deposition(LMD),the kinds of powder materials that can be used are limited,while the equipment components are made of various *** many components have to be repaired with heterogeneous ***,it is difficult to match the mechanical properties between the repaired layer and the substrate due to the diff erent *** on the high flexibility of raw materials and processes in LMD,an in-situ alloying method is proposed herein for tailoring the mechanical properties of LMDed *** diff erent mixing ratios of Fe314 and 316 L stainless steel powders as the control parameter,the microstructure and mechanical properties of B-bearing austenitic stainless steel fabricated by LMD in-situ alloying with diff erent proportions of Fe314 and 316 L particles were *** the increase in the concentration of 316 L steel,the volume fraction of the eutectic phase in deposited B-bearing austenitic stainless steel reduced,the size of the austenite dendrite increased,the yield strength and ultimate tensile strength decreased monotonically,while the elongation increased ***,the fracture mode changed from quasi-cleavage fracture to ductile *** adding 316 L powder,the yield strength,tensile strength,and elongation of deposited B-bearing austenitic stainless steel could be adjusted within the range of 712 MPa–257 MPa,1325 MPa–509 MPa,and 8.7%–59.3%,***,this work provides a new method and idea for solving the performance matching problem of equipment components in the field repair.

关键词： Additive manufacturing Laser metal deposition In-situ alloying B-bearing austenitic stainless steel Mechanical properties

Depression among caregivers of patients with dementia:Associative factors and management approaches

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World Journal of Psychiatry 2022年第1期12卷 59-76页

作者： Si-sheng huang Division of Geriatric Psychiatry Department of PsychiatryChanghua Christian HospitalChanghua 500Taiwan

As elderly people increasingly come to represent a higher proportion of the world’s population,various forms of dementia are becoming a significant chronic disease *** World Health Organization emphasizes dementia care as a public health priority and calls for more support for family caregivers who commonly play a significant,central role in dementia *** care of someone with dementia is a long-term responsibility that can be stressful and may lead to depression among family *** and related behavioral and cognitive changes among caregivers could in turn affect the status and prognosis of the dementia *** review article explores depression in dementia caregivers and summarizes proposed mechanisms,associated factors,management and research findings,and proposes future research directions.

关键词： Dementia Depression Caregiver Caregiver burden Activities of daily living Functional status

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人民币汇率的影响因素及变化趋势研究

特区经济 2006年第11期 12-14页

作者：黄盛北京大学光华管理学院北京100871

人民币汇率问题是当前的一个研究热点,本文拟在研究改革开放以来人民币汇率变动及我国汇率制度演变的基础上,分析影响人民币汇率的一些主要因素,并结合这些影响因素和制度改革的演化,对未来人民币汇率的变化趋势进行研究。

关键词：人民币汇率汇率制度影响四素变化趋势

Influence of Continuous Bending Process on Texture Evolution and Mechanical Properties of AZ31 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第3期31卷 225-233页

作者： Ting-Zhuang Han Guang-sheng huang Lun huang Bin Jiang Guan-Gang Wang Ai-Tao Tang Fu-sheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing Research Center for Advanced Materials Chongqing Academy of Science & Technology

Mg-3Al-lZn alloy sheets have been deformed by continuous bending（CB）to investigate the effects of pro-cessing parameters（bending angle and repetitive passes）on the texture and *** samples exhibited a bimodal microstructure with abnormal growth grains in the surface region and fine grains distributed in the center after CB process followed by *** texture evolution measured by XRD indicated that the basal poles were rotated from ND toward RD,and the texture intensity decreased with the bending angle decreasing and repetitive passes *** with the as-received sample,the yield strength of CBA-120-2 sample significantly decreased from 183 to 112 MPa,and a smaller r-value and a larger n-value were *** formability of CB processed samples in annealing condition was significantly enhanced with the highest of Erichsen value of 5.4 mm,increased by about 135%.The improvement of formability was likely attributed to the weakened and RD-tilt basal texture and coarse grains in the surface part.

关键词： Magnesium alloy Continuous bending Microstructure Texture Stretch formability