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上海交通大学学报 2003年第S1期37卷 250-254页

作者： LIU Yuan fang 1. LIN Li 2 (1. Library of Dalian university of Technology, Dalian 1.6024, China 2. 21.st Century Development and Research Center, Dalian 1.6023)

Digital library is a process of exploiting more scientific methods to construct a social knowledge network. It represents an “extension” from a traditional library. The core and essence is to build a favorable surroundings for knowledge accumulation, knowledge transfer and knowledge communication. Management communication covers information transfer and organization cooperation. Compared with traditional library, the management communication in digital library shoulders the commitment to support knowledge innovation. On the basis of analysis of the connotation of digital library, this paper analysed the aspects of management communication, including communicators, communication styles, contents, channels and outer communication, all of which tries to construct an integrated model of management communication in a digital library and turns a library into an actual “knowledge fountain”.

关键词： university’s digital library knowledge management management communication

Analysis on the long term discharge of a catchment

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Journal of Environmental Sciences 2000年第3期12卷 279-285页

作者： HONG Lin 1. TAKASE Keiji 2, SATO Koichi 2 (1. Wuhan university of Hydraulic and Electric Engineering, Wuhan 430072, China 2. Ehime university, Japan) Wuhan university of Hydraulic and Electric Engineering Wuhan 430072 China Ehime university Japan

In this study, the characteristics of the long term discharge of a Terraced Paddy Field Catchment are studied. 2 Kind of Tank Models are proposed and used to simulate the discharge of the catchment. The characteristics of the model simulations of the discharge of the catchment are analyzed and compared with those of a forest catchment.

关键词： long term discharge model simulation terraced paddy field catchment

The mechanism of breakdown in laminar-turbulent transition of a supersonic boundary layer on a flat plate-temporal mode

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Science China(Physics,Mechanics & Astronomy) 2005年第5期48卷 614-625页

作者： HUANG Zhangfeng 1. CAO Wei 1.2 & ZHOU Heng 1.2 1. Department of Mechanics, Tianjin university, Tianjin 300072, China 2. Liu-Hui Center of Applied Mathematics, Nankai university and Tianjin university, Tianjin 300072, China Department of Mechanics Tianjin University Tianjin China Liu-Hui Center of Applied Mathematics Nankai University and Tianjin University Tianjin China

Temporal mode direction numerical simulation has been done for the transition of a supersonic boundary layer on a flat plate with Mach number 4.5. Analysis of the result showed that during the breakdown process in laminar-turbulent transition, the mechanism causing the mean flow profile to evolve swiftly from laminar to turbulent was that the modification of mean flow profile by the disturbances,when they became larger,led to a remarkable change of its stability characteristics. Though the most unstable T-S wave was of second mode for laminar flow, the first mode waves played the key role in the breakdown process in laminar-turbulent transition.

关键词： supersonic boundary layer, transition, breakdown.

Discovery of Paleogene marine stratum along the southern side of Yarlung-Zangbo suture zone and its implications in tectonics

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Science China Earth Sciences 2005年第5期48卷 647-661页

作者： LI Guobiao 1., WAN Xiaoqiao 1., LIU Wencan 1., LIANG Dingyi 1.& Hyesu Yun 2 1. China university of Geosciences, Beijing 1.0083, China 2. Chungnam National university, Daejon, 305-350, Korea China university of Geosciences Beijing China Chungnam National university Daejon Korea

The Jiachala Formatiom is a new lithostratigraphic unit set up in this paper. This is the first report on the Paleogene marine sequences and microfaunas in Gyangze to the southern side of the Yarlung-Zangbo suture zone. On the basis of fossil abundance, species diversity, dominant species and first and last occurrences of key species, three dinoflagellate assemblages and three polynological assemblages were recognized in the Jiachala Formatiom. They are in ascending ord.r as follows: Apectodinium quinquelatum-Apectodinium hyperacanthum, Cannin- gia chinensis-Palaeoperidinium pyrophorum and Cymatiosphaera reticulosa-Samlandia chla- mydophora dinoflagellate assemblages, and Arliaceoipollenites baculatus-Anacolosidites sub- trudens, Aglaoreidia cyclops-Pinuspollenites microinsigis, and Elaeangnacites asper-Ilexpol- lenites iliacus polynological Assemblages. Accord.ng to the assemblages, the age of the Jiachala Formation is referred to Paleocene-early Eocene. The preliminary study on the Jiachala Forma- tion shows that this group of Paleogene deposits accumulated in an underfilled peripheral fore- land basin which was in response to the load of the crust thickening resulted from the Asia-India collision. The stratigraphic evidences provided by the evolution of foreland basin indicate that the India-Asia initional collision should occure near the Cretaceous/Paleogene boundary. The de- velopment and evolution of the southern Tibet foreland basin was under the control of the stress field from the subduct-collision between India and Asia and the structure pattern of the basement. The withering of Tethys Sea might occur after early Eocene in the Gyangze basin and should be after Priabonian of late Eocene in southern Tibet.

关键词： Paleogene marine strata, Jiachala Formation, microfossils, underfilled peripheral foreland basin, initional collision, Gyangze.

基于车辆轨迹数据的港口集卡预约系统配额方案优化

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大连海事大学学报 2024年

作者：马文耀王玉孙世超 1.广东海洋大学船舶与海运学院 2.大连海事大学交通运输工程学院广东海洋大学船舶与海运学院大连海事大学交通运输工程学院

港口集卡预约系统的应用能显著减少集卡在港周转时间，提升码头运营效率，进而增强港口竞争力。然而，在优化预约配额方案时，现有方法面临诸多挑战，包括动态性、随机性捕捉难，理论假设局限，以及数据获取处理复杂等。为此，本文创新... 详细信息

港口集卡预约系统的应用能显著减少集卡在港周转时间，提升码头运营效率，进而增强港口竞争力。然而，在优化预约配额方案时，现有方法面临诸多挑战，包括动态性、随机性捕捉难，理论假设局限，以及数据获取处理复杂等。为此，本文创新性地利用集卡的GPS轨迹数据，全面捕获了集卡从到达港口至完成作业的全过程周转时间，并基于此建立了单位预约时间窗口内集卡到达数量与其在港总周转时间之间的映射关系。进一步地，利用该映射关系，构建了一个更为精确简洁的配额优化模型，并对集卡预约配额方案进行了优化求解。实验结果表明，优化后的预约配额方案有效减少了高峰期的集卡到达量，同时提高了低谷期的车辆到达数，从而大幅节省了集卡在港的总周转时间。这一成果不仅有助于缓解港口的拥堵压力，也为进一步提升港口运营效率提供了有力支撑。

关键词：集卡预约系统配额方案优化 GPS轨迹数据车辆周转时间

A new orthogonality relationship for orthotropic thin plate theory and its variational principle

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1., LONG Yuqiu 2 & LIU Guangdong 1.1. College of Civil Engineering, Hunan university, Changsha 41.082, China 2. Department of Civil Engineering, Tsinghua university, Beijing 1.0084, China College of Civil Engineering Hunan University Changsha China Department of Civil Engineering Tsinghua University Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Distribution of actinomycetes in oil contaminated ultisols of the Niger Delta(Nigeria)

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Journal of Environmental Sciences 2000年第3期12卷 296-302页

作者： J.P. Essien 1. E. D. Udosen 2 (1. Department of Microbiology, university of Uyo, Nigeria 2. Department of Chemistry and Biochemistry, university of Uyo,Nigeria) Department of Microbiology University of Uyo Nigeria Department of Chemistry and Biochemistry University of Uyo Nigeria

The distribution of actinomycetes in oil contaminated sandy loam ultisols of the Niger Delta region of Nigeria was studied to aid in understanding the effect of hydrocarbons on indigenous microbial population in tropical soils. The average total counts of actinomycetes in all the oil samples analysed was 1. 3 cfu/g. Higher counts of actinomycetes were observed during the dry season than during the wet season. The counts of hydrocarbonoclastic actinomycetes correlated positively with the total count of actinomycetes. The actinomycetes were generally restricted to the top soil(0—1. cm soil depth) although a seemingly deeper(down to 40 cm soil depth) distribution was noticed in the dry season. The isolates included oil degrading species of Actinoplanes, Norcadia, Streptomyces and Streptosporangium. Their high oil utilization ability indicates their positive potential and role in the bioremediation of oil spilled soils.

关键词： actinomycetes oil contaminated ultisols

Distribution of dissolved organic carbon in and near the Prydz Bay, Antarctica

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Acta Oceanologica Sinica 2003年第4期22卷 547-556页

作者： Qiu Yusheng1. Chen Min1. Huang Yipu1. Liu Guangshan1.1. Department of Oceanography, Xiamen university, Xiamen 361.05, China. Department of Oceanography Xiamen University Xiamen 361005 China

During the 1.th Chinese National Antarctic Research Expedition (CHINARE) (from November 1.99 to April 2000) seawater samples were collected for (DOC) determination in the Prydz Bay and its nearby sea areas. DOC concentrations were determined-by high temperature catalytic oxidation (HTCO) method. The results shows that DOC concentrations, in the upper water column (0 similar to 1.0 in) range from 1..3 to 1.1.1.mumol/dm(3), with averaging 52.5 mumol/dm(3) (n = 55). These values are slightly higher than those reported for the Ross Sea, the Pacific Ocean and others. Profiles of DOC concentration in the study areas show a decreasing concentration with increasing depth in the upper 1.0 m, which is related to biological activities in the water column. DOC concentrations below 1.0 in are relatively constant with a mean of 40.4 gammamol/dm(3). These DOC are unactive for physical and biological activities and are called refractory DOC. Concentration of the refractory DOC in the study area is consistent with the previous reported values for the Southern Ocean, which is about 41.mumol/dm(3). Based on the difference between the measured DOC concentration and the refractory concentration, the excess DOC concentration in the upper column can be calculated at every station. The excess DOC shows a spatial variability with a higher excess in the north of 64degreesS and little excess in the south of 64degreesS. In conclusion, DOC concentrations in the Prydz Bay and its nearby sea areas,are, consistent with the previous reported values in the Southern Ocean, which show a low DOC concentration with respect to the other oceans. Distribution of surface DOC concentrations in the study areas shows an increase from the southwestern to the northeastern, which is ascribed to the northern spread of continental shelf water from the Prydz Bay in summer. Contents of DOC and their distribution in the Prydz Bay and its nearby sea areas are mainly controlled by physical and biological processes.

关键词： The Prydz Bay Antarctica dissolved organic carbon

Effect of an impurity on 3-electron quantum dots in magnetic fields

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Science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 521-530页

作者： LIU Yimin1.2, HUANG Gangming1.& BAO Chengguang1.1. Department of Physics, Zhongshan university, Guangzhou 51.275, China 2. Department of Physics, Shaoguan university, Shaoguan 51.005, China Department of Physics Zhongshan University Guangzhou China Department of Physics Shaoguan University Shaoguan China

The ground-state property of a 2-dimensional 3-electron quantum dot (QD) subjected to an external magnetic fieldB and affected by an impurity is studied. The impurity is located at thez-axis by a distanced from the plane of the dot. The evolution of the angular momentumL o and the spinS o of the ground state in accord.nce withB andd has been calculated, and the results are summarized and plotted in a (L o,S o) diagram. The spatial distribution of the electrons (the size and the geometric features) and the optical absorption have also been investigated. The (L o S o) diagram indicates thatL o andS o may jump whend and/orB vary. It was found that, due to the constraints arising from symmetry, each symmetric geometry is accessible only to a specific group of states having specificL o andS o.

关键词： quantum dot, ground state, charged impurity, magnetic field.