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Algorithms for degree-constrained Euclidean Steiner minimal tree

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Journal of Systems Engineering and Electronics 2008年第4期19卷 735-741页

作者： Zhang Jin ma liang Zhang Liantang School of management Univ. of Shanghai for Science and Technology Shanghai 200093 P. R. China Computer and Information Engineering Coll. Univ. of Henan Kaifeng 475001 P. R. China

A new problem of degree-constrained Euclidean Steiner minimal tree is discussed, which is quite useful in several fields. Although it is slightly different from the traditional degree-constrained minimal spanning tree, it is also NP-hard. Two intelligent algorithms are proposed in an attempt to solve this difficult problem. Series of numerical examples are tested, which demonstrate that the algorithms also work well in practice.

关键词： degree-constrained Euclidean Steiner minimal tree simulated annealing ant algorithm

One-dimensional microstructure-assisted intradermal and intracellular delivery

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Bio-Design and manufacturing 2019年第1期2卷 24-30页

作者： Wensen Jiang liang ma Xiaobin Xu materials Science and Engineering School. Tongji University Shanghai 201804. China State Key Laboratory of Fluid Power and Mechatronic Systems. Zhejiang University. Hangzhou 310058. China School of Mechanical Engineering. Zhejiang University Hangzhou 310058 China

The advancement in the materials manufacturing at micrometer and nanometer scales has already enabled numerous applications in electronics, optics, chemistry, biology and medicine. Biomedical devices carrying micro-/nanostructures are currently being widely used in drug delivery, drug release, biosensing and therapy. New clinical methods for disease diagnosis and treatments are being developed enabled by nanotech no logy. One-dimensional (ID) structures are playi ng an importa nt role in the direct drug delivery both in vivo and ex vivo among various micro-/nanostructures. Here, in this paper, we reviewed recent progresses made on next-generation intradermal and intracellular delivery strategies and applications with focus on ID microstructure-based approaches.

关键词： Biomedical devices Intradermal Intracellular ID nanostructure Drug delivery

Direct Laser Writing Facility for Fabrication of Submicron mask

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Chinese Physics Letters 2014年第4期31卷 185-188页

作者： ZHU Feng ma Jian-yong Information Optics Laboratory Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800

Direct laser writing technique has become a well-established, multi-functional and flexible method for fabricating high quality diffractive optical elements. We propose and build a maskless direct laser writing system with the ability to produce a sub-micron feature size. The high precision lithography is realized by using the astigmatic autofocus method. The minimum feature size of the system, breaking through the diffraction limit with the chromium layer, can achieve 300hm with the 405nm blue laser. A 50 x 50ram2 chromium grating mask with a period of 1 #m and line width of 300 nm is fabricated. This facility will be useful for the fabrication of large-scale submicron diffraction optical elements in the future.

关键词： FABRICATION (manufacturing) DIFFRACTIVE optical elements CHROMIUM -- Spectra BLUE lasers OPTICAL diffraction ASTIGmaTISM (Optics)

Unlicensed Spectrum Sharing Game Between LEO Satellites and Terrestrial Cognitive Radio Networks

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Chinese Journal of Aeronautics 2012年第4期25卷 605-614页

作者： XIE Zhuochen ma LU liang Xuwen Shanghai Engineering Center for Micro-satellites Shanghai 200050China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China Graduate University of Chinese Academy of Sciences Beijing 100049China

By cognitive radio,the low Earth orbit（LEO） satellites may prefer to operate in the unlicensed spectrum which is open to all the users,and compete for the limited resources with terrestrial cognitive radio networks（CRNs）.The competition can be regarded as a game and analyzed with game *** particular unlicensed spectrum sharing problem is modeled here,and the special properties of ＂spatially-distinguished-interference＂ and the short period of the interactions between satellites and terrestrial CRNs are ***,the problem is formulated as a ＂partially-blind＂ finitely repeated prisoner＇s dilemma by game ***,we begin with two promising spectrum sharing schemes,which can be used to enforce the frequency reuse among the remotely located terrestrial CRN players as well as to overcome the observation *** analysis and comparison,it is proposed that the novel refreshing-contrite-tit-for-tat（R-CTFT） is the optimal spectrum sharing *** results verify that it can be used to utilize the spectrum most efficiently.

关键词： satellite communication systems cognitive radio unlicensed spectrum sharing spatially-distinguished-interference finitely repeated prisoner's dilemma partially-blind refreshing-contrite-tit-for-tat

Water molecules on the liquid superlubricity interfaces achieved by phosphoric acid solution

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Biosurface and Biotribology 2018年第3期4卷 94-98页

作者： Yuan Gao Liran ma yong liang Bohong Li Jianbin Luo School of Metallurgy Engineering Xi'an University of Ardhitecture and TechnologyXi'an710055People's Republic of China State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing100084People's Republic of China Laser Micro/Nano-Fabrication Laboratory School of Mechanical EngineeringBeiing Institute ofTechnologyBeijing100081People's Republic of China

The superlubricity mechanism of phosph olipid molecules on biological surfaces and interfaces has been receiving much *** the superlubricity can be achieved with a phosphoric acid aqueous solution,the interaction of the phosphate group with the water molecule is considered to be the key to ***,no direct evidence has been offered to distinctly interpret the underlying mech anism of superlubricity,due to the limitations in the method for the detection of interfacial molecules,especially water molecules on the *** using sum-freq uency g en eration(SFG)vibrational spectroscopy,which is extremely sensitive to interfacial molecules,the authors were able to explore the underlying microscopic mechanism for superlubricity in a phosphoric acid system,which might be related to interfacia I water *** trapping the phosphoric acid aqueous solution between silicon nitride and silica surfaces,they discovered that phosphoric acid could exercise a great influence on the ordered structure of interfacial water molecules,contributing to SFG spectral changes in the broad O-H bond stretching *** work directly revealed the interfacial interaction between water and phosphoric acid molecules in liquid superlubricity interfaces,which could shed new light on the microscopic mechanism of liquid superlubricity.

关键词： interfacial liquid interaction

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秦汉时期乡村借贷新探

史学集刊 2025年第1期 75-87页

作者：马新山东大学历史学院山东济南250100

秦汉乡村借贷既非古典借贷,亦非严格意义上的高利贷,它只是被当时乡村社会所普遍接受的特有借贷形式。这一借贷形式具有较强内循性,多以乡村居民间借贷为主,富商大贾以及城市商业资本难以介入;也有较强应急性,多是乡村居民生存急需时的... 详细信息

秦汉乡村借贷既非古典借贷,亦非严格意义上的高利贷,它只是被当时乡村社会所普遍接受的特有借贷形式。这一借贷形式具有较强内循性,多以乡村居民间借贷为主,富商大贾以及城市商业资本难以介入;也有较强应急性,多是乡村居民生存急需时的借贷行为,经营性或扩大再生产的借贷颇为少见;还有较强行政性,王朝官方既是重要放贷方,又是监管者与仲裁人,直接介入乡村经济事务。这些特点减少了商品经济对乡村社会的冲击,在一定时期内有利于乡村社会发展与繁荣。但是,从长时段视角看,它也影响乡村社会对外来经济要素的接纳,制约乡村社会进一步发展,使其长期处于简单再生产的循环之中。

关键词：秦汉乡村社会借贷关系

Guided Mode Resonance Transmission Filters Working at the Intersection Region of the First and Second Leaky Modes

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Chinese Physics Letters 2012年第2期29卷 214-216页

作者： ma Jian-yong FAN yong-Tao Shanghai Institute of Fine Mechanics and Optics Chinese Academy of SciencesShanghai 201800

Based on the guided mode resonance effect,single-layer transmission filters are *** is found that there is an intersection region in which the strong modulation waveguide modes TE_(0) and TE_(2) can be simultaneously excited by the second and first diffraction orders,respectively.A very high transmission peak emerges when the leaky modes interact with each *** on the normalized eigen-function of a single-layer waveguide grating,the high resonance transmission filters can be designed at any central *** order to demonstrate this concept,we design narrow line-shaped band pass filters with a central wavelength at 0.8,1.06 and 10.6μm.

关键词： waveguide filters narrow

A novel technique for measuring 3D deformation of adhesively bonded single lap joint

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Science China(Physics,Mechanics & Astronomy) 2016年第1期59卷 58-65页

作者： Bing Pan LuJun ma yong Xia Institute of Solid Mechanics Beihang University State Key Lab of Automotive Safety and Energy Tsinghua University

An easy-to-implement yet practical single-camera microscopic stereo-digital image correlation(stereo-DIC) technique is proposed for surface three-dimensional(3D) deformation measurement of singe lap joint(SLJ) samples subjected to mechanical loads. The basic principles, optical configurations and implementation procedures of the proposed technique are described in detail. Compared with existing single-camera 2D-DIC technique, which has been regularly used for in-plane deformation measurement of a SLJ specimen, the proposed technique offers the special merit of simultaneously determining all the three displacement components by simply adding two additional optical elements to existing single-camera 2D-DIC systems. The accuracy and effectiveness of the proposed technique is demonstrated by measuring the 3D deformation of a SLJ specimen subjected to quasi-static tensile loads.

关键词： digital image correlation single lap joint deformation measurement

Dependence Rayleigh competing risks model with generalized censored data

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Journal of Systems Engineering and Electronics 2020年第4期31卷 852-858页

作者： WANG liang ma Jin’ge SHI Yimin School of mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China School of mathematics Yunnan Normal UniversityKunming 650500China School of mathematics and Statistics Xidian UniversityXi’an 710071China Department of Applied mathematics Northwestern Polytechnical UniversityXi’an 710072China

The inference for the dependent competing risks model is studied and the dependent structure of failure causes is modeled by a marshall-Olkin bivariate Rayleigh distribution. Under generalized progressive hybrid censoring(GPHC), maximum likelihood estimates are established and the confidence intervals are constructed based on the asymptotic theory. Bayesian estimates and the highest posterior density credible intervals are obtained by using Gibbs sampling. Simulation and a real life electrical appliances data set are used for practical illustration.

关键词： dependence competing risks bivariate distribution generalized progressive hybrid censoring(GPHC) likelihood estimation Bayesian analysis