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The high level language for system specification: A model-driven approach to systems engineering

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第1期7卷 180-214页

作者： Hamzat Olanrewaju Aliyu Oumar maıga mamadou Kaba Traore School of Informa.ion and Communication Technology Federal University of Technology Minna Gidan-Kwanu Campus MinnaNigeria Universit´e des Sciences des Techniques et des Technologies BamakoMali LIMOS CNRS UMR 6158 Universite Blaise Pascal Clermont-FerrandFrance

We present HiLLS(High Level Language for System Specification),a graphical formalism that allows to specify Discrete Event System(DES)models for analysis using methodologies like simulation,formal methods and ***’syntax is built from the integration of concepts from System Theory and Software Engineering aided by simple concrete notations to describe the structural and behavioral aspects of *** paper provides the syntax of HiLLS and its simulation semantics which is based on the Discrete Event System Specification(DEVS)*** DEVS-based Modeling and Simulation(M&S)perspective,HiLLS is a platform-independent visual language with generic expressions that can serve as a front-end for most existing DEVS-based simulation environments with the aid of Model-Driven Engineering(MDE)*** also suggests ways to fill some gaps in existing DEVS-based visual formalisms that inhibit complete specification of the behavior of complex *** provide a case study to illustrate the core features of the language.

关键词： HiLLS modeling and simulation integrated formalism DEVS Object-Z

基于分子束外延技术可控制备Bi原子团簇的研究

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原子与分子物理学报 2025年第2期42卷 79-84页

作者：马玉麟郭祥丁召贵州大学大数据与信息工程学院贵阳550025 贵州省微纳电子与软件技术重点实验室贵阳550025 半导体功率器件可靠性教育部工程研究中心贵阳550025

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇... 详细信息

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s、15 s、20 s的沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s,高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

关键词：分子束外延 Bi原子团簇生长温度沉积时长经典成核理论晶体生长动力学

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基于分子束外延技术可控制备ga原子团簇的研究

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原子与分子物理学报 2025年第3期42卷 77-84页

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的ga源温度下制备ga原子团簇.实验结... 详细信息

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的ga源温度下制备ga原子团簇.实验结果表明,ga源温度的升高导致ga的蒸发量增加,进而沉积在Si衬底表面的ga原子增多,ga原子自组装成团簇,最终表现为ga原子团簇的高度升高.第二组对照实验分别在3 s、6 s、10 s、40 s、50 s、60 s的沉积时长下制备ga原子团簇.实验结果表明,沉积时长增加导致团簇的高度逐渐增加,主要由新吸附原子和竞争效应驱动.第三组对照实验分别在0 s、60 s、300 s的退火时长下制备ga原子团簇.实验结果表明,退火时长的增加导致团簇的高度下降和团簇内的原子重新排列和分布有关.第四组对照实验分别在420℃、500℃的退火温度下制备ga原子团簇.实验结果表明,升温至500℃退火会促进ga原子团簇呈现有序排列,是表面原子的热运动和ga原子团簇与Si(100)的晶格匹配度的共同作用的结果.

关键词： MBE ga原子团簇 ga源温度沉积时长退火时长

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Analyzing Changes in maize Leaves Orientation due to GxExM Using an Automatic Method from RGB Images

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Plant Phenomics 2023年第2期5卷 239-252页

作者： ma.io Serouart Raul Lopez-Lozano gaëtan daubige maëva Baumont Brigitte Escale Benoit De Solan Frédéric Baret Arvalis Institut du végétal228route de l’aérodrome-CS 4050984914 Avignon Cedex 9France INRAE Avignon UniversitéUMR EMMAHUMT CAPTE228route de l’aérodrome-CS 4050984914 Avignon Cedex 9France Arvalis Ecophysiology21 Chemin de Pau64121 MontardonFrance

The sowing pattern has an important impact on light interception efficiency in maize by determining the spatial distribution of leaves within the *** orientation is an important architectural trait determining maize canopies light *** studies have indicated how maize genotypes may adapt leaves orientation to avoid mutual shading with neighboring plants as a plastic response to intraspecific *** goal of the present study is 2-fold:firstly,to propose and validate an automatic algorithm(Automatic Leaf Azimuth Estima.ion from Midrib detection[ALAEM])based on leaves midrib detection in vertical red green blue(RGB)images to describe leaves orientation at the canopy level;and secondly,to describe genotypic and environmental differences in leaves orientation in a panel of 5 maize hybrids sowing at 2 densities(6 and 12 plants.m^(−2))and 2 row spacing(0.4 and 0.8 m)over 2 different sites in southern *** ALAEM algorithm was validated against in situ annotations of leaves orientation,showing a satisfactory agreement(root mean square[RMSE]error=0.1,R^(2)=0.35)in the proportion of leaves oriented perpendicular to rows direction across sowing patterns,genotypes,and *** results from ALAEM permitted to identify significant differences in leaves orientation associated to leaves intraspecific *** both experiments,a progressive increase in the proportion of leaves oriented perpendicular to the row is observed when the rectangularity of the sowing pattern increases from 1(6 plants.m^(−2),0.4 m row spacing)towards 8(12 plants.m^(−2),0.8 m row spacing).Significant differences among the 5 cultivars were found,with 2 hybrids exhibiting,systematically,a more plastic behavior with a significantly higher proportion of leaves oriented perpendicularly to avoid overlapping with neighbor plants at high *** in leaves orientation were also found between experiments in a squared sowing pattern(6 plants.m^(−2),0.4 m

关键词： cultivar spacing pattern

Carrier-driven magnetic and topological phase transitions in twodimensional III-V semiconductors

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Nano Research 2023年第2期16卷 3443-3450页

作者： Yan Li Xinru ma Hongwei Bao Jian Zhou Fei ma Jingbo Li State Key Laboratory for Mechanical Behavior of materials Xi’an Jiaotong UniversityXi’an 710049China Center for Alloy Innovation and Design Xi’an Jiaotong UniversityXi’an 710049China Institute of Semiconductors South China Normal UniversityGuangzhou 510631China

III-V semiconductors such as gaAs are widely studied as promising candidates for high-speed integrated *** these applications for conventional bulk structures,their fundamental physical properties in the nanoscale limit are still in scarcity,which is of great importance for the development of *** this work,we demonstrate that the III-V semiconductor MX(M=Al,ga,In;X=P,As,Sb)in its two-dimensional(2D)limit could exhibit double layer honeycomb(DLHC)configuration and distorted tetrahedral coordination,according to our first-principles calculations with HSE06 hybrid *** is found that surface reconstruction endows 2D III-V DLHCs with pronouncedly different electronic and magnetic properties from their bulk counterparts due to strong interlayer ***-hat-shape bands emerge at the top valence bands of pristine AlP,gaP,InP,AlAs,and InAs DLHCs,inducing the density of states showing a sharp van Hove singularity near the Fermi *** a result,these DLHCs exhibit itinerant magnetism upon moderate hole doping,while the rest gaAs,AlSb,gaSb,and InSb DLHCs become magnetic under tensile strain with hole *** an exchange splitting of the localized pz states at the top valence bands,the hole-doped III-V DLHCs become half-metals with 100%***,the InSb DLHC shows inverted band structure near the Fermi level,bringing about nontrivial topological band structures in stacked InSb DLHC due to the strong spin-orbital *** III-V DLHCs expand the members of 2D material family and their exotic magnetic and topological properties may offer great potential for applications in the novel electronic and spintronic devices.

关键词： III-V semiconductors HSE06 hybrid functional Mexican-hat-shape bands magnetism topological bands

Controlled WISP-1 shRNA Delivery Using Thermosensitive Biodegradable Hydrogel in the Treatment of Osteoarthritis

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Journal of Bionic Engineering 2015年第2期12卷 285-293页

作者： Gong Yubao ma Hecheng Liu Jianguo Department of Bone and Joint First Hospital of Jilin University Changchun 130021 China

This paper presents a new method of delivering shRNA with biodegradable, thermosensitive PLga-PEG-PLga hydrogels for gene treatment of osteoarthritis （OA）. OA is a chronic debilitating disease. Without the proper treatment and prognosis, it may result in the loss of joint function in aged people. Currently, gene therapy targeted on WISP-1 has emerged as an alternative method for OA treatment. In order to constantly release shRNA at 37.0 ℃, we synthetized the hydrogels via ring-opening copolymerization of lactide （LA） and glycolide （ga） using Polyethylene glycol （PEG Mn = 1000） and stannous octoate （Sn（Oct）2, 95%） as the macroinitiator and catalyst. First, the PLga-PEG-PLga copolymer was mixed with WISP- 1 shRNA and PEI-Lys in distilled water at 4.0 ℃. Then, the WISP-lshRNA/PEI-Lys loaded hydrogel was formed after incubation of the mixed solution at 37.0 ℃. During tests, the plasmid was released from this hydrogel complex constantly, and enhanced the transfection efficiency of WISP-1 shRNA. In addition, silencing WISP-1 results to lower expression of MMP-3 and AdaMTS, and the accumulation of HBP 1 in synoviocytes. Therefore, the hydrogel containing WISP-1 shRNA is demonstrated an efficient way for the treatment of OA.

关键词： osteoarthritis biodegradable thermosensitive hydrogel PLga-PEG-PLga WISP-1

Fast Quantification of the Mixture of Polycyclic Aromatic Hydrocarbons Using Surface-Enhanced Raman Spectroscopy Combined with PLS-ga-BP Network

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Journal of Ocean University of China 2021年第6期20卷 1451-1458页

作者： YAN Xia SHI Xiaofeng ma Jun Optics and Optoelectronics Laboratory of Qingdao Ocean University of ChinaQingdao 266100China

To realize the fast and accurate quantitative analysis of the mixture of polycyclic aromatic hydrocarbons(PAHs),surface-enhanced Raman spectroscopy(SERS)coupled with multivariate calibrations were *** this study,three kinds of calibration algorithms were used to quantitative analysis of the mixture of naphthalene(Nap),phenanthrene(Phe),and pyrene(Pyr).Firstly,partial least squares(PLS)algorithm was used to select characteristic variables,then the global search capability of genetic algorithm(ga)was used for the determining of the initial weights and thresholds of back propagation(BP)neural network so that local minima was *** PLS-ga-BP model exhibited superiority to quantify PAHs mixture,which achieved R2=0.9975,0.9710,0.9643,ARE=10.07%,19.28%,16.72%and RMSE=13.10,5.40,5.10 nmol L−1 for Nap,Phe,Pyr(in the PAHs mixture)concentration prediction *** forecast error,ARE and RMSE have been reduced more than 50%and 60%respectively compared with the whole spectral BP *** study indicates that accurate quantitative spectroscopic analysis of the mixture of PAHs samples can be achieved through the combination of SERS technique and PLS-ga-BP algorithm.

关键词： polycyclic aromatic hydrocarbons(PAHs) surface enhanced Raman spectral(SERS) back propagation(BP)algorithm multi-component quantitative analysis

Provenance of Conglomerate and Sandstone from Early Permian Shoushangou Forma.ion in Xi Ujimqin,Inner Mongolia:Implications for Understanding Paleo-Asian Ocean Subduction

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 10-31页

作者： ZHANG Yingli GUO Xianqing ma Shouxian MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China Chinese Academy of Geological Sciences Beijing 100037China

During the Late Carboniferous to Early Permian,a rift was formed by post-collisional extension after ocean closure or an island arc-related basin formed by Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin ***,the closure time of the PAO is still under ***,to identify the origin of the PAO,the geochemistry and U-Pb age of zircons were analyzed for the extra-large deep marine,polymict clastic boulders and sandstones in the Shoushangou Forma.ion within the *** analyses revealed magmatic activity and tectonic *** conglomerates include megaclasts of granite(298.8±9.1 ma)and granodiorite porphyry(297.1±3.1 ma),which were deposited by muddy debris *** of this study demonstrated that the boulders of granitoids have the geochemistry of typical I-type granite,characterized by low Zr+Nb+Ce+Y and low ga/Al *** granitoid boulders were formed in island arc setting,indicating the presence of arc magmatism in the area that is composed of the Late Carboniferous to Early Permian subduction-related granitoid in southern Xi *** diagrams for determining sedimentary provenance using major and trace elements indicate that Shoushangou sediments originated from continental island arc-related felsic *** zircon U-Pb age cluster of 330–280 ma was obtained,indicating input from granite,ophiolite,Xilin Gol complex,and Carboniferous sources to the *** basin was geographically developed behind the arc during the Early Permian period because the outcropped intrusive rocks in the Late Carboniferous to Early Permian form a volcanic *** comprehensive analyses of source areas suggest that Shoushangou sediments developed in a backarc basin in response to the northward subduction of the *** backarc basin and intrusive rocks,in addition to previously published Late Carboniferous to Early Permian magmatic rocks of arc unit in Xilin Gol,confirm the presence of an Early Permian trencharc-basin system in the region,r

关键词： provenance analysis backarc basin Shoushangou Forma.ion Early Permian Central Asian Orogenic Belt

An overview of Hadoop applications in transportation big data

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第5期10卷 900-917页

作者： Changxi ma Mingxi Zhao Yongpeng Zhao School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou 730070China Key Laboratory of Railway lndustry on Plateau Railway Transportation Intelligent management and Control Lanzhou Jiaotong UniversityLanzhou 730070China gansu Highway Traffic Construction Group Co. Ltd.Lanzhou 730000China

As an open-source cloud computing platform,Hadoop is extensively employed in a variety of sectors because of its high dependability,high scalability,and considerable benefits in processing and analyzing massive amounts of ***,to derive valuable insights from transportation big data,it is essential to leverage the Hadoop big data platform for analysis and *** summarize the latest research progress on the application of Hadoop to transportation big data,we conducted a comprehensive review of 98 relevant articles published from 2012 to the ***,a bibliometric analysis was performed using VOSviewer software to identify the evolution trend of ***,we introduced the core components of ***,we systematically reviewed the98 articles,identified the latest research progress,and classified the main application scenarios of Hadoop and its optimization *** on our analysis,we identified the research gaps and future work in this *** review of the available research highlights that Hadoop has played a significant role in transportation big data research over the past ***,the focus has been on transportation infrastructure monitoring,taxi operation management,travel feature analysis,traffic flow prediction,transportation big data analysis platform,traffic event monitoring and status discrimination,license plate recognition,and the shortest ***,the optimization framework of Hadoop has been studied in two main areas:the optimization of the computational model of Hadoop and the optimization of Hadoop combined with *** research results have been achieved in the field of transportation big ***,there is less systematic research on the core technology of Hadoop,and the breadth and depth of the integration development of Hadoop and transportation big data are not *** the future,it is suggested that Hadoop may be combined with other big data frameworks such a

关键词： Informa.ion technology Transportation big data Hadoop Intelligent transportation Cloud computing