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Rare Metals 2021年第9期40卷 2530-2537页

作者： Cheng-de Li Hui-Min Gu Wei Wang Shuai Wang Ling-Ling Ren Yu-Chun Zhai Zhen-Biao Wang zhu ming School of Metallurgy Northeastern UniversityShenyang 110006China Research Laboratory of WAAM Process Inner Mongolia Metal Material Research InstituteNingbo 315100China Technology department North East Industrial Materials and Metallurgy Co.Ltd.Fushun 113200China

Numerous studies have addressed the advantages of wire arc additive manufacturing for manufacturing aluminum alloys. However, the role of Ti content in aluminum alloys has rarely been discussed. Herein, the effect of Ti content on the microstructure and properties of Al–7 Si–0.6 Mg alloys was studied. The alloys were deposited via wire arc additive manufacturing and were examined through optical microscopy(OM), scanning electron microscopy(SEM), and electronic universal testing. The results show that the increase of Ti content gradually promotes the increase of the secondary dendrite arm spacing and also has an increasing tendency to form pores defect in the as-deposited alloys. The change of titanium content also affects the difference between horizontal and vertical direction properties of the alloy. The alloy with a Ti content of 0.112 wt% exhibits the best comprehensive properties. There is no difference in its horizontal and vertical direction properties. The tensile strengths, yield strengths, and elongation of this alloy(T6) along the vertical and horizontal axis are 356 and 355 MPa, 307 and308 MPa, and 8.5% and 8.0%, respectively.

关键词： Wire arc additive manufacturing Al–7Si–0.6Mg alloy Microstructure and properties Titanium

Father of biological cloning in China

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Protein & Cell 2010年第9期1卷 793-794页

作者： Zuoyan zhu ming Li Le Kang Institute of Hydrobiology Chinese Academy of SciencesWuhan 430072China College of Life Science Peking UniversityBeijing 100871China Beijing Institutes of Life Science Chinese Academy of SciencesBeijing 100101China

Dizhou Tong(***)is a well-familiar name in China,as there is a story about him in one of the elementary school *** story describes how he came from a poor family and could not go to middle school until the age of 17,and how his resolution and diligence made him a successful *** in the academic community,he is remembered and respected for another reason—the outstanding achievement of cross-species cloning in fish.

关键词： remember cloning story

Multiparticle Generalization of Remote State Preparation

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Communications in Theoretical Physics 2004年第2X期42卷 211-214页

作者： LIUJin-ming HANJiu-Rong WANGYu-zhu LaboratoryforQuantumOptics ShanghaiInstituteofOpticsandFineMechanicstheChineseAcademyofSciencesShanghai201800China

We present a scheme for preparing remotely a three-particle pure entangled state via entanglement swapping,and then we directly generalize it to the multiparticle case. It is shown that by using N pairs of bipartite EPR states as the quantum channel, remote preparation of some specially chosen N-particle pure entangled states can be achieved faithfully with an N-particle orthonormal basis measurement and only N bits of classical information.

关键词：投影测量纠缠量子通信量子信息核磁共振测量量子管

Enantiomeric Separation of Amino Alcohols by Ion-pair Chromatography

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Chinese Chemical Letters 2001年第4期12卷 355-356页

作者： ming Hua HU Xiu zhu XU department of Chemistry Zhejiang UniversityHangzhou 310027

Enantiomers of four amino alcohols were resolved by ion-pair chromatography with (+)-10-camphorsulphonic acid as chiral counter ion. Studies of the influence of the mobile phase composition, the solute structure and the mobile phase flow-rate on separation are presented. Under the optimized conditions enantiomeric propanolol, norephedrine, metropolol and salbutamol were separated using dichloromethane-1-pentanol (97:3 v/v) as mobile phase on Lichrospher-100-DIOL column.

关键词： Ion-pair chromatography chiral separation amino alcohols (+)-10-camphorsulphonic acid.

面向工业动态取送货问题的分解多目标进化算法

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计算机科学 2025年第1期52卷 331-344页

作者：蔡俊创朱庆灵林秋镇李坚强明仲深圳大学计算机与软件学院广东深圳518060

由于工业动态取送货问题具有垛口、时间窗、容量、后进先出装载等多种约束,现有的车辆路径算法大多只优化一个加权目标函数,在求解过程中难以保持解的多样性,所以容易陷入局部最优区域而停止收敛。针对上述问题,提出了一种融合高效局部... 详细信息

由于工业动态取送货问题具有垛口、时间窗、容量、后进先出装载等多种约束,现有的车辆路径算法大多只优化一个加权目标函数,在求解过程中难以保持解的多样性,所以容易陷入局部最优区域而停止收敛。针对上述问题,提出了一种融合高效局部搜索策略的分解多目标进化算法。首先,该算法将工业动态取送货问题建模成多目标优化问题,进一步将其分解为多个子问题并同时进行求解。然后,利用交叉操作增强解的多样性,再使用局部搜索加快收敛速度。因此,该算法在求解该多目标优化问题时能够更好地平衡解的多样性和收敛性。最后,从种群中选择一个最好的解来完成当前时段的取送货任务。基于64个华为公司实际测试问题的仿真结果表明,该算法在求解工业动态取送货问题上的性能表现最优;同时,在20个京东物流大规模配送问题上的实验也验证了该算法良好的泛化性。

关键词：动态取送货问题分解方法多目标进化算法局部搜索组合优化

Impact of Gully on Soil Moisture of Shrubland in Wind-Water Erosion Crisscross Region of the Loess Plateau

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Pedosphere 2008年第5期18卷 674-680页

作者： HUO zhu SHAO ming-An R. HORTON Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China）. Graduate University of the Chinese Academy of Sciences Beijing 100049 （China） Agronomy department of Iowa State University Ames IA 50011-1010 （USA）

The most serious erosion on the Loess Plateau of China exists in the wind-water erosion crisscross region where the annual precipitation is about 400 mm,the ecological environment is very fragile,and water is the key limiting factor for improving the environment. In this study,changes of soil moisture content for Caragana korshinskii Kom. shrubland in the gully bank of the Loess Plateau were studied using the methods of soil sampling and neutron probe. A typical gully(75 m long,28 m wide,and 10 m deep) was selected,and six neutron probe access tubes(6 m long) were installed at points 50,100,200,300,400,and 500 cm from the gully border for obtaining soil moisture data from July to October 2004 at approximately 10 d intervals. Soil samplings were simultaneously carried out for moisture determination at the six points. Results showed that the soil moisture of the shrubland in the gully bank significantly varied between 300 and 400 cm in the horizontal direction and up to 600 cm in vertical direction of the gully. Seasonal changes in soil moisture revealed a curve with a single peak that occurred at the end of August or early September. A linear regression equation was fit for soil water storage and the distance from the gully border,with coefficients depending on rainfall characteristics,sampling point,and time of measurement.

关键词： erosion gully shrubland soil moisture

Experimental investigation on the failure mechanism of a rock landslide controlled by a steep-gentle discontinuity pair

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Journal of Mountain Science 2019年第6期16卷 1258-1274页

作者： HUANG Da ZHONG zhu GU Dong-ming State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China

A type of rock landslide is very common in practical engineering, whose stability is mainly controlled by the rock bridge between the steep tensile crack at the crest and the low-inclination weak discontinuities at the toe(namely, ligament is the term for the locking section in the slope). To obtain a deeper understanding into the failure process of this kind of landslide, twenty-four physical slope models containing a steep-gentle discontinuity pair(a steep crack in the upper part and a low-inclination discontinuity in the lower part) were tested by applying vertical loads at the crests. The results indicate that the inclination angle of the ligament(θ) has great influence on the failure and stability of this type of rock slope. With the change of θ, three failure patterns(five subtypes) concerning the tested slopes can be observed, i.e., tensile failure of the ligament(Type 1), tension-shear failure of the ligament(Type 2) and two-stage failure of the main body(Type 3). The failure process of each failure mode presents five stages in terms of crack development, vertical load, horizontal/vertical displacements and strains in the ligaments. The specific range of the ligament angle between different failure patterns is summarized. The discussion on the failure resistances and ductility of different failure patterns, and the guiding significances of the experimental findings to the stability evaluation and the reinforcement were conducted.

关键词： Rock landslide Failure pattern Failure evolution Locking section Crack coalescence

Self-sensing active magnetic bearing using real-time duty cycle

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第8期14卷 600-611页

作者： ming TANG Chang-sheng zhu Jie YU State Grid Sichuan Electric Power Research Institute College of Electrical Engineering Zhejiang University

In a self-sensing active magnetic bearing (AMB) system driven by pulse width modulation (PWM) switching power amplifiers, the rotor position information can be extracted from coil current and voltage signals by a specific signal demodulation process. In this study, to reduce the complexity of hardware, the coil voltage signal was not filtered but measured in the form of a duty cycle by the eCAP port of DSP (TMS320F28335). A mathematical model was established to provide the relationship between rotor position, current ripple, and duty cycle. Theoretical analysis of the amplitude-frequency characteristic of the coil current at the switching frequency was presented using Fourier series, Jacobi-Anger identity, and Bessel function. Experimental results showed that the time-varying duty cycle causes infinite side frequencies around the switching frequency. The side frequency interval depends on the varying frequency of the duty cycle. Rotor position can be calculated by measuring the duty cycle and demodulating the coil current ripple. With this self-sensing strategy, the rotor system supported by AMBs can steadily rotate at a speed of 3000 r/min.

关键词： Self-sensing Active magnetic bearing (AMB) Frequency spectrum characteristic

Optimizing inter-view prediction structures for multi-view video coding using simulated annealing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 155-162页

作者： Zheng zhu Dong-xiao LI ming ZHANG Institute of Information and Communication Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 310027 China

New video applications, such as 3D video and free viewpoint video, require efficient compression of multi-view video. In addition to temporal redundancy, exploiting the inter-view redundancy is crucial to improve the performance of multi-view video coding. In this paper, we present a novel method to construct the optimal inter-view prediction structure for multi-view video coding using simulated annealing. In the proposed model, the design of the prediction structure is converted to the arrangement of coding order. Then, a simulated annealing algorithm is employed to minimize the total cost for obtaining the best coding order. This method is applicable to arbitrary irregular camera arrangements. As experiment results reveal, the annealing process converges to satisfactory results rapidly and the generated optimal prediction structure outperforms the reference prediction structure of the joint multi-view video model (JMVM) by 0.1-0.8 dB PSNR gains.

关键词： Multi-view video coding Prediction structure Simulated annealing

Numerical simulation of single roller melt spinning for NdFeB alloy based on finite element method

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Rare Metals 2020年第10期39卷 1145-1150页

作者： Xu-Chao Wang ming Yue Dong-Tao Zhang Wei-Qiang Liu ming-Gang zhu College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124.China Central Iron and Steel Research Institute Beijing 100081China

The numerical simulation model of single roller melt spinning for rapid quenching process of NdFeB alloy was built,and the vacuum chamber,cooling roller and sample were taken into account as a *** existing mature technology was in order to verify the correctness of *** rapid quenching ribbons with different roll speeds were used as the simulation *** results of the numerical simulation and experiments show that the validity of the model has been testified and the reasons of the formation of complete quenching ribbons and by-product have been *** experimental thickness of the ribbons is proportional to the theoretical *** the same spray condition,with the roll speed increasing,the thickness decreases *** the speed range of25-30 m·s^(-1),the simulated calculation date is close to the experimental date,which can be considered as an ideal technological parameter.

关键词： NdFeB Melt spinning Finite element method Numerical simulation