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中国沿海集装箱港口集中度研究

大连海事大学学报 2015年第3期41卷 82-86页

作者：李丹栾维新片峰大连海事大学交通运输管理学院辽宁大连116026

利用行业集中度对我国沿海集装箱港口行业的市场结构演化过程进行分析.分析发现,近30年来,我国集装箱港口行业的市场结构由最初的寡占Ⅰ型发展到如今的寡占Ⅲ型,并且集中度有进一步下降的趋势,市场结构向寡占Ⅳ型发展.对比美国集装箱港... 详细信息

利用行业集中度对我国沿海集装箱港口行业的市场结构演化过程进行分析.分析发现,近30年来,我国集装箱港口行业的市场结构由最初的寡占Ⅰ型发展到如今的寡占Ⅲ型,并且集中度有进一步下降的趋势,市场结构向寡占Ⅳ型发展.对比美国集装箱港口集中度发现,近10年来,我国集装箱港口集中度略高于美国,两国同属于寡占Ⅲ型的市场结构.但我国集装箱吞吐量是美国的3.59倍,我国前4位港口的平均集装箱吞吐量是美国的4倍,港口运输压力明显大于美国.过大的运输压力会给港口及其所在城市带来相应的负面影响.因此,在边缘挑战机制的作用下,我国沿海集装箱港口集中度有进一步下降的空间.

关键词：沿海集装箱港口集中度市场结构中美对比边缘挑战

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共同配送合并策略及其配送成本

长安大学学报（自然科学版） 2006年第3期26卷 68-71页

作者：徐同连栾琨贾洪飞吉林大学交通学院吉林长春130025

共同配送即合并运送,其目的在于将地域内随机发生且重叠运送的零星货物加以统合化与整合化。分析了存货合并、车辆装载能力合并及转运点合并3种合并运送策略,通过建立合并运送的收益与亏损之间的平衡模型,计算出各合并策略的配送成本。... 详细信息

共同配送即合并运送,其目的在于将地域内随机发生且重叠运送的零星货物加以统合化与整合化。分析了存货合并、车辆装载能力合并及转运点合并3种合并运送策略,通过建立合并运送的收益与亏损之间的平衡模型,计算出各合并策略的配送成本。阐述了合并收益与降低运输成本、合并亏损与增加存货成本和延长配送路线之间的平衡关系,从而得出各合并策略的适用条件,为合并运送的实施和运输资源的优化配置提供了理论基础。

关键词：交通工程合并策略配送成本合并收益合并亏损

ERROR ANALYSIS OF A STABILIZEd FINITE ELEMENT METHOd FOR THE GENERALIZEd STOKES PROBLEM

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Journal of computational Mathematics 2020年第2期38卷 254-290页

作者： Huoyuan duan Roger c.E.Tan School of Mathematics and Statistics Wuhan UniversityWuhan 430072China department of Mathematics National University of SingaporeSingapore

This paper is devoted to the establishment of sharper a priori stability and error estimates of a stabilized finite element method proposed by Barrenechea and Valentin for solving the generalized Stokes problem,which involves a viscosity v and a reaction consta nt *** the establishmen t of sharper st ability estimates and the help of ad hoc finite element projections,we can explicitly establish the dependence of error bounds of velocity and pressure on the viscosity z/,the reaction constant cr,and the mesh size *** analysis reveals that the viscosity y and the reaction constant a respectively act in the numerator position and the denominator position in the error estimates of velocity and pressure in standard norms without any ***,the stabilization method is indeed suitable for the generalized Stokes problem with a small viscosity u and a large reaction constant *** sharper error estimates agree very well with the numerical results.

关键词： Generalized Stokes equations Stabilized finite element method Error estimates.

Gradient descent decomposition of force-field motor primitives optogenetically elicited for motor mapping of the murine lumbosacral spinal cord

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Zoological Research 2023年第3期44卷 604-619页

作者： Paola Salmas Vincent c.K cheung School of Biomedical Sciences and Gerald Choa Neuroscience InstituteThe Chinese University of Hong KongHong Kong SARChina Kunming Institute of Zoology-The chinese University of Hong Kong(KIZ-cUHK)Joint Laboratory of Bioresources and Molecular Research of common diseases Hong Kong SARChina

Generating diverse motor behaviors critical for survival is a challenge that confronts the central nervous system(cNS)of all *** movement execution,the cNS performs complex calculations to control a large number of neuromusculoskeletal *** theory of modular motor control proposes that spinal interneurons are organized in discrete modules that can be linearly combined to generate a variety of behavioral *** modules have been previously represented as stimulus-evoked force fields(FFs)comprising isometric limb-endpoint forces across workspace ***,we ask whether FFs elicited by different stimulations indeed represent the most elementary units of motor control or are themselves the combination of a limited number of even more fundamental motor *** probe for potentially more elementary modules,we optogenetically stimulated the lumbosacral spinal cord of intact and spinalized Thy1-chR2 transgenic mice(n=21),eliciting FFs from as many single stimulation loci as possible(20-70 loci per mouse)at minimally necessary *** found that the resulting varieties of FFs defied simple categorization with just a few *** used gradient descent to further decompose the FFs into their underlying basic force fields(BFFs),whose linear combination explained FF *** mice,we identified 4-5 BFFs with partially localizable but overlapping representations along the spinal *** BFFs were structured and topographically distributed in such a way that a rostral-to-caudal traveling wave of activity across the lumbosacral spinal cord may generate a swing-to-stance gait *** BFFs may represent more rudimentary submodules that can be flexibly merged to produce a library of motor modules for building different motor behaviors.

关键词： Motor mapping Optogenetics Spinal cord Motor primitives Traveling wave

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南通市食管癌危险因素成组资料病例对照研究

现代预防医学 2009年第18期36卷 3413-3414+3417页

作者：栾婕蓝绍颖南通大学公共卫生学院流行病学与卫生统计学教研室

[目的]探讨江苏省南通市食管癌发病的危险因素,为制定预防和控制食管癌的对策和措施提供信息和依据。[方法]采用以医院为基础的频数匹配病例对照研究方法,对南通市185例食管癌病人及185例对照进行多变量测量。运用非条件Logistic回归对... 详细信息

[目的]探讨江苏省南通市食管癌发病的危险因素,为制定预防和控制食管癌的对策和措施提供信息和依据。[方法]采用以医院为基础的频数匹配病例对照研究方法,对南通市185例食管癌病人及185例对照进行多变量测量。运用非条件Logistic回归对可疑因素进行单因素和多因素分析。[结果]单因素Logistic回归分析显示与食管癌有关联的因素有:喜食咸食、进食快、喜食硬食、喜食烫食、三餐定时、经常使用农药、常食圆子年糕、重大应激事件、脾气性格暴躁、家族史、工作类型、常食水果;多因素Logistic回归分析发现喜食咸食(OR=3.122,95%cI:1.778～5.482)、进食快(OR=2.753,95%cI:1.553～4.880)、喜食硬食(OR=2.534,95%cI:1.169～5.496)、喜食烫食(OR=2.581,95%cI:1.059～4.030)、重大应激事件(OR=4.611,95%cI:2.569～8.278)、家族史(OR=2.011,95%cI:1.143～3.537)是南通市食管癌发生的危险因素。[结论]南通市食管癌是一种由多种致癌因素引起疾病,即在环境危险因素和遗传因素的作用下发生,因此,对其应采取综合性的预防措施。

关键词：食管癌成组资料病例对照研究危险因素

A Grid Middleware for distributed Java computing with MPI Binding and Process Migration Supports

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Journal of computer Science & Technology 2003年第4期18卷 505-514页

作者：陈琳王卓立 Francis c.M.Lau department of computer Science and Information Systems The University of Hong Kong P.R. China

"Grid" computing has emerged as an important new research field. With years of efforts, grid researchers have successfully developed grid technologies including security solutions,resource management protocols, information query protocols, and data management services. However, as the ultimate goal of grid computing is to design an infrastructure which supports dynamic,cross-organizational resource sharing, there is a need of solutions for efficient and transparent task re-scheduling in the *** this research, a new grid middleware is proposed, called G-JavaMPI. This middleware adds the parallel computing capability of Java to the grid with the support of a Grid-enabled message passing interface (MPI) for inter-process communication between Java processes executed at different grid points. A special feature of the proposed G-JavaMPI is the support of Java process migration with post-migration message redirection. With these supports, it is possible to migrate executing Java process from site to site for continuous computation, if some site is scheduled to be turned down for system reconfiguration. Moreover, the proposed G-JavaMPI middleware is very portable since it requires no modification of underlying OS, Java virtual machine, and MPI package. Preliminary performance tests have been conducted. The proposed mechanisms have shown good migration efficiency in a simulated grid environment.

关键词： grid middleware MPI java process migration

A Revised checklist of Amphibians and Reptiles in camiguin Sur,Misamis Oriental,Mindaanao,Philippines

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Asian Herpetological Research 2020年第1期11卷 28-43页

作者： Russell Evan L·VENTURINA Ynigo Luis c·dEL PRAdO Rhim Ayyah c·KAMIR Marlon N·BALMORES Arvin c·dIESMOS department of Biology College of ScienceDe La Salle UniversityTaft AvenueManila The Graduate School University of Santo TomasEsparaManila Mindanao State Uniersity-ligan Institute of Technology Iligan CityMindanao Herpetology Section Zoology DivisionNational Museum of Natural HistoryPhilippines

The Philippines is listed as one of the world's megadiverse countries despite its small ***,it is also on the list of global biodiversity conservation *** the threat of extinction at an all-time high,better understa nding of the archipelago's biodiversity will provide invalua ble baseline information for proper conservation *** we provide an upda ted checklist on the herpetological biodiversity of ca miguin Sur,Misa mis Oriental,Minda nao,*** surveys and specimen collection from the municipality of Mambajao resulted in a total of 28 species(13 anurans,11 lizards,and four snakes)-all well represented by voucher *** data provides seven additional species records,upda ting the island's total amphibian and reptile species count to 57,with about half Philippine *** in the new records are three invasive alien species of amphibians:The cane Toad Rhinella marina,the Greenhouse Frog Eleutherodatylus planirstris,and the Asiatic Painted Narrowmouth Toad Kaloula pulchra.

关键词： camiguin Sur amphibians and reptiles biodiversity conservation

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迈向中国工程学:关于工程知识论的若干思考

工程研究（跨学科视野中的工程） 2021年第5期13卷 463-470页

作者：栾恩杰国防科技工业科学技术委员会北京100048

工程知识集成是现代工程学的一个重要理念,而工程知识扩展及集成的创新功能是在工程运行中产生的。这在当今“巨型规模、多学科融合、多领域集成”的长周期工程建设中体现得尤为突出。现代工程技术就是在大型计算技术支撑下的知识系统集... 详细信息

工程知识集成是现代工程学的一个重要理念,而工程知识扩展及集成的创新功能是在工程运行中产生的。这在当今“巨型规模、多学科融合、多领域集成”的长周期工程建设中体现得尤为突出。现代工程技术就是在大型计算技术支撑下的知识系统集成,这在AI技术深化和普及的状态下已经成为世界各国工程界的共识,而基于模型的系统工程(MBSE)则是与工程知识系统相对应的系统知识工程。中国学者应当立足人工智能最新发展,借鉴基于模型的系统工程思想,总结探月工程这类重大工程的实践经验,致力于发展中国特色的工程学,以便更好地服务于未来我国的重大工程实践活动。

关键词：系统工程基于模型的系统工程人工智能中国工程学

Longwall top coal caving design for thick coal seam in very poor strength surrounding strata

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International Journal of coal Science & Technology 2021年第4期8卷 641-658页

作者： H.Jangara c.Atilla Ozturk Mining Engineering department Faculty of MinesIstanbul Technical UniversityIstanbulTurkey

Alpu lignite field is an important coal deposit with nearly 2 billion tons of coal resources located in the middle of *** mine deposit consists of three main *** thickness of two of them vary from 4 to 30 *** surrounding rock mass is very poor in terms of *** high clay content and weak rock mass make mechanized mining *** this research,applicability of the longwall top coal caving method was *** very weak strength behavior of the coal and the surrounding strata increases the importance of research in the mine site in terms of ground *** aim is to design the mechanized longwall mine based on ground control *** of all,classification of the roof,coal,inter-burden,and floor strata were classified based on geotechnical ***,cavability index,shield,and floor bearing capacity were *** methods were applied to understand the limitations of a mechanized system that is very critical due to the very low strength *** to the main results,roof strata was classified as immediately caving while mining height was calculated as 5-6 ***,the relations among geotechnical characterizations of roof and floor strata,cutting and caving heights,and required shield capacity were presented based on analytical and numerical *** proposed approach can be used as a ground control method for the applicability as well as the limitations of mechanized longwall mining design in weak strata conditions.

关键词： coal Geotechnics Ground control Longwall mining Numerical methods