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The organization and traffic engineering of a quantum cryptography network

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Science China(Physics,Mechanics & Astronomy) 2012年第9期55卷 1562-1570页

作者： zhao YuKang zhao meisheng zhao Yong CHEN ZengBing Hefei National Laboratory for Physical Science at Microscale and Department of Modern Physics University of Science and Technology of China Hefei 230026 China Shandong Institute of Quantum Science & TechnologyCo. Ltd. Jinan 250161 China Anhui Quantum Communication Technology Co. Ltd. Hefei 230088 China

How many users can a quantum cryptography network support when certain services are demanded? The answer to this question depends on three factors:the speed of quantum key distribution,the organization and traffic engineering of the quantum cryptography network,and the engineering of *** this article we focus on the second factor which is lacked in the literature to our knowledge but in urgent need for constructing an optimized large-scale quantum cryptography *** order to provide an overall understanding about a quantum cryptography network,we also briefly introduce the characteristics of quantum cryptography and service engineering.

关键词： quantum key distribution network

Long time evolution of a spin interacting with a spin bath in arbitrary magnetic field

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1262-1265页

作者： zhao YuKang zhao meisheng CHEN ZengBing Hefei National Laboratory for Physical Science at Microscale and Department of Modern Physics University of Science and Technology of China Shandong Institute of Quantum Science & Technology Co. Ltd.

We introduce a completely different method to calculate the evolution of a spin interacting with a sufficient large spin bath,especially suitable for treating the central spin model in a quantum dot(QD).With only an approximation on the envelope of central spin,the symmetry can be exploited to reduce a huge Hilbert space which cannot be calculated with computers to many small ones which can be solved *** method can be used to calculate spin-bath evolution for a spin bath containing many(say,1000)spins,without a perturbative limit such as strong magnetic field condition,and works for long-time regime with sufficient *** the spin-bath evolution can be calculated for a wide range of time and magnetic field,an optimal dynamic of spin flip-flop can be found,and more sophisticated approaches to achieve extremely high polarization of nuclear spins in a QD could be developed.

关键词： dipole-dipole interaction spin bath low-field regime long-time evolution numerical simulation

A Femur-Implant Model for the Prediction of Bone Remodeling Behavior Induced by Cementless Stem

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Journal of Bionic Engineering 2013年第3期10卷 350-358页

作者： He Gong Lingyan Kong Rui Zhang Juan Fang meisheng zhao State Key Laboratory of Automotive Simulation and Control Jilin University Changchun 130025 P. R. China Department of Engineering Mechanics Jilin University Changchun 130025 P. R. China Department of Cataract Eye Hospital of the Second Clinical Hospital of Jilin University Jilin University Changchun 130051 P. R. China

Bone remodeling simulation is an effective tool for the prediction of long-term effect of implant on the bone tissue, as well as the selection of an appropriate implant in terms of architecture and material. In this paper, a finite element model of proximal femur was developed to simulate the structures of internal trabecular and cortical bones by incorporating quantitative bone functional adaptation theory with finite element analysis. Cementless stems made of titanium, two types of Functionally Graded Material （FGM） and flexible ＇iso-elastic＇ material as comparison were implanted in the structure of proximal femur respectively to simulate the bone remodeling behaviors of host bone. The distributions of bone density, von Mises stress, and interface shear stress were obtained. All the prosthetic stems had effects on the bone remodeling behaviors of proximal femur, but the degrees of stress shielding were different. The amount of bone loss caused by titanium implant was in agreement with the clinical obser- vation. The FGM stems caused less bone loss than that of the titanium stem, in which FGM I stem （titanium richer at the top to more HAP/Col towards the bottom） could relieve stress shielding effectively, and the interface shear stresses were more evenly distributed in the model with FGM 1 stem in comparison with those in the models with FGM II （titanium and bioglass） and titanium stems. The numerical simulations in the present study provided theoretical basis for FGM as an appropriate material of femoral implant from a biomechanical point of view. The next steps are to fabricate FGM stern and to conduct animal experiments to investigate the effects of FGM stem on the remodeling behaviors using animal model.

关键词： functionally graded material bone remodeling stress shielding proximal femur implant

Effects of Materials of Cementless Femoral Stem on the Functional Adaptation of Bone

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Journal of Bionic Engineering 2012年第1期9卷 66-74页

作者： He Gong Wei Wu Juan Fang Xin Dong meisheng zhao Tongtong Guo Department of Engineering Mechanics Jilin University Changchun 130022 P. R. China Department of Neurosurgery The First Hospital of Jilin University Changchun 130021 P. R. China Department of Cataract Eye Hospital of the Second Clinical Hospital of Jilin University Jilin University Changchun 130051 P. R. China School of Natural Sciences and Humanities Harbin Institute of Technology Shenzhen Graduate School Shenzhen 518055 P. R. China

The objective of this paper is to identify the effects of materials of cementless femoral stem on the functional adaptive behaviors of bone. The remodeling behaviors of a two-dimensional simplified model of cementless hip prosthesis with stiff stem, flexible ＇iso-elastic＇ stem, one-dimensional Functionally Graded Material （FGM） stern and two-dimensional FGM stem for the period of four years after prosthesis replacement were quantified by incorporating the bone remodeling algorithm with finite element analysis. The distributions of bone density, von Mises stress, and interface shear stress were obtained. The results show that two-dimensional FGM stem may produce more mechanical stimuli and more uniform interface shear stress compared with the stems made of other materials, thus the host bone is well preserved. Accordingly, the two-dimensional FGM stem is an appropriate femoral implant from a biomechanical point of view. The numerical simulation in this paper can provide a quantitative computational paradigm for the changes of bone morphology caused by implants, which can help to improve the design of implant to reduce stress shielding and the risk of bone-prosthesis interface failure.

关键词： functionally graded material bone remodeling interface shear stress stress shielding femur implant

Regional Variations in Trabecular Morphological Features of Femoral Head of Patients with Proximal Femoral Fractures

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Journal of Bionic Engineering 2015年第2期12卷 294-303页

作者： Linwei Lv Guangwei Meng He Gong Dong Zhu Jiazi Gao meisheng zhao School of Mechanical Science and Engineering Jilin University Changchun 130022 China School of Mechanical Engineering Tianjin University of Technology Tianjin 300384 China Department of Orthopedic Surgery the First Clinical Hospital of Jilin University Changchun 130021 China Department of Cataract Eye Hospital of the Second Clinical Hospital of Jilin University Changchun 130000 China

The regional microstructural variations in femoral head from proximal femoral fracture patients were investigated. Mi- cro-CT scanning was performed on seven femoral heads from proximal femoral fracture patients. Each femoral head was divided into three regions according to the trabecular orientation from the fovea of femoral head to the femoral neck. Eight three-dimensional trabecular cube models were reconstructed from each region. A total of 154 trabecular cubic models were reconstructed because the corresponding areas for 14 cubic models were damaged during the surgeries. Eight trabecular mor- phological parameters were measured and analyzed, namely, trabecular thickness （***）, trabecular separation （***）, spe- cific bone surface （BS/BV）, bone volum在不 fraction （BV/TV）, structural model index （SMI）, degree of anisotropy （DA）, trabecular pattern factor （***）, and trabecular number （Tb.N）. Bivariate correlation analyses were performed for all mor- phological parameters. One-way ANOVA tests were performed to analyze the differences of each parameter among three re- gions. Post-hoc multiple comparisons （Student-Newman-Keuls method） were performed to analyze the morphological differ- ence between two regions. Trabecular bone of proximal femoral fracture patients significantly degenerated in all regions of femoral heads. BV/TV was statistically correlated with ***, ***, BS/BV, ***, and Tb.N （p 〈 0.05）. Statistical differences in morphological parameters were observed between regions （p 〈 0.05）. The trabecular strength in the middle regions was significantly higher than that in other regions because of the relationships between morphological parameters and mechanical parameters. Trabeculae in the medial region were more uniform and stable along each direction than those in the lateral region. Most trabeculae in the lateral region only grew along the weight-bearing direction, and those along the other directions de- generated significantly. This study provide

关键词： femoral head trabeculae proximal femur fracture morphological parameter micro-CT

Multilevel carbon architecture of subnanoscopic silicon for fast‐charging high‐energy‐density lithium‐ion batteries

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Carbon Energy 2024年第4期6卷 256-268页

作者： meisheng Han Yongbiao Mu Lei Wei Lin Zeng Tianshou zhao Shenzhen Key Laboratory of Advanced Energy Storage Southern University of Science and TechnologyShenzhenChina SUSTech Energy Institute for Carbon Neutrality Southern University of Science and TechnologyShenzhenChina Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhenChina

Silicon(Si)is widely used as a lithium‐ion‐battery anode owing to its high capacity and abundant crustal ***,large volume change upon cycling and poor conductivity of Si cause rapid capacity decay and poor fast‐charging capability limiting its commercial ***,we propose a multilevel carbon architecture with vertical graphene sheets(VGSs)grown on surfaces of subnanoscopically and homogeneously dispersed Si–C composite nanospheres,which are subsequently embedded into a carbon matrix(C/VGSs@Si–C).Subnanoscopic C in the Si–C nanospheres,VGSs,and carbon matrix form a three‐dimensional conductive and robust network,which significantly improves the conductivity and suppresses the volume expansion of Si,thereby boosting charge transport and improving electrode *** VGSs with vast exposed edges considerably increase the contact area with the carbon matrix and supply directional transport channels through the entire material,which boosts charge *** carbon matrix encapsulates VGSs@Si–C to decrease the specific surface area and increase tap density,thus yielding high first Coulombic efficiency and electrode compaction ***,C/VGSs@Si–C delivers excellent Li‐ion storage performances under industrial electrode *** particular,the full cells show high energy densities of 603.5 Wh kg^(−1)and 1685.5 Wh L^(−1)at 0.1 C and maintain 80.7%of the energy density at 3 C.

关键词： fast charging high energy densities lithium‐ion batteries multilevel carbon architecture subnanoscopic silicon anode

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基于机器视觉的烟叶杂物在线识别剔除研究

科技创新与应用 2024年第26期14卷 42-45页

作者：邓银正赵梅生杨兴权伍先艾先宏毛杰波湖南中烟工业有限责任公司零陵卷烟厂湖南永州425006

在工业智能化和自动化的发展背景下,在烟草生产过程中,利用机器视觉技术来实现烟叶杂物的在线识别和剔除,能够提高杂物剔除率,保障烟草产品的品质及质量,扩大烟草企业的销售市场。该研究主要对烟叶杂物在线识别剔除系统结构及工作原理... 详细信息

在工业智能化和自动化的发展背景下,在烟草生产过程中,利用机器视觉技术来实现烟叶杂物的在线识别和剔除,能够提高杂物剔除率,保障烟草产品的品质及质量,扩大烟草企业的销售市场。该研究主要对烟叶杂物在线识别剔除系统结构及工作原理进行概述,指出基于机器视觉技术下系统软件算法和硬件的进一步优化,并开展现场测试,以期利用全新的杂物分拣算法构建分拣性能强大的烟叶杂物在线识别剔除系统,增强生产线的自动化程度,进一步降低烟叶杂物误检率,增强烟草企业竞争力。

关键词：机器视觉烟草杂物在线识别剔除

The structure–activity relationships of Rh/CeO_(2)-ZrO_(2) catalysts based on Rh metal size effect in the three-way catalytic reactions

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Nano Research 2024年第8期17卷 6870-6878页

作者： Dongming Chen Weixin zhao Zihao Xu Zheng zhao Juanyu Yang Yongke Hou Yongqi Zhang Zongyu Feng meisheng Cui Xiaowei Huang National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.Beijing 100088China Grirem Hi-Tech Co. Ltd.Sanhe 065201China General Research Institute for Nonferrous Metals Beijing 100088China

With the continuous tightening of automotive emission regulations and the increasing promotion of energy-efficient hybrid vehicles,new challenges have arisen for the low-temperature performance of three-way catalysts(TWCs).To guide the design of next-generation TWCs,it is essential to further develop our understanding of the relationships between microstructure and catalytic ***,Rh/CeO_(2)–ZrO_(2) catalysts were synthesized with different Rh metal dispersion by using a combination of the wet impregnation method and reduction *** catalysts included Rh single-atom catalysts,cluster catalysts,and nanoparticle *** results showed that the Rh nanoparticle catalyst,with an average size of 1.9 nm,exhibited superior three-way catalytic performance compared to the other *** on the catalytic activity in a series of simple reaction atmospheres such as CO+O_(2),NO+CO,and hydrocarbons(HCs)+O_(2) and operando infrared spectroscopy,we found that metallic Rh sites on Rh nanoparticles are the key factor responsible for the low-temperature catalytic performance.

关键词： Rh/CeO_(2)-ZrO_(2) catalyst Rh metal size effect Rh nanoparticles three-way catalytic performance

AF36圆锥破碎机在人工砂石系统中的应用分析

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人民长江 2011年第14期42卷 102-104页

作者：赵梅生葛洲坝集团大岗山厂房人工砂石项目部四川石棉625409

大岗山水电站厂房人工骨料加工系统需要满足高峰期高强度的混凝土粗细骨料供应和施工期不同级配混凝土的骨料需求。介绍了人工骨料加工系统工程的特点,详尽论述了系统工艺流程和主要设备选型。重点介绍了阿尔斯泰克AF36圆锥破碎设备的... 详细信息

大岗山水电站厂房人工骨料加工系统需要满足高峰期高强度的混凝土粗细骨料供应和施工期不同级配混凝土的骨料需求。介绍了人工骨料加工系统工程的特点,详尽论述了系统工艺流程和主要设备选型。重点介绍了阿尔斯泰克AF36圆锥破碎设备的技术特性,并从处理能力、出口间隙的调整范围和经济学方面将其与同类圆锥破进口设备进行了比较。结果表明,阿尔斯泰克AF36圆锥破碎设备具有产量高、性能稳定、破碎产品粒型好、自动化程度高、操作简单、损耗较小和生产运行成本低等优点。

关键词：砂石系统破碎机层压破碎理论细破