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Three-dimensional virtual representation for the whole process of dam-break floods from a geospatial storytelling perspective

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International Journal of Digital Earth 2022年第1期15卷 1637-1656页

作者： weilian Li Jun Zhu Jan-henrik Haunert Lin Fu Qing Zhu Youness Dehbi Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople's Republic of China Institute of Geodesy and Geoinformation University of BonnBonnGermany

The objective of disaster scenes is to share location-based risk information to a large audience in an effective and intuitive ***,current studies on three-dimensional(3D)representation for dam-break floods have the following limitations:(1)they are lacking a reasonable logic to organize the whole process of dam-break floods,(2)they present information in a way that cannot be easily understood by *** storytelling helps to create exciting experiences and to explain complex relationships of geospatial *** article proposes a three-dimensional virtual representation method for the whole process of dam-break floods from a geospatial storytelling *** creation of a storyline and a storytelling-oriented representation of dam-break floods are discussed in ***,a prototype system based on WebGL is developed to conduct an experiment *** results of the experiment show that the proposed method can effectively support 3D representation of the spatiotemporal process of dam-break ***,the statistical results indicate that the storytelling is useful for assisting participants in understanding the occurrence and development of dam-break floods,and is applicable to the popularization of disaster science for the general public.

关键词： Geospatial storytelling dam-break flood spatiotemporal process virtual representation 3D scene

Design,fabrication and characterization of dual-channel real space transfer transistor

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Frontiers of Electrical and Electronic Engineering in China 2009年第2期4卷 234-238页

作者： weilian GUO Shilin ZHANG Xin YU School of Electronic Information Engineering Tianjin UniversityTianjin 300072China

In this paper,using aδ-doping dual-channel structure and GaAs substrate,a real space transfer transistor(RSTT)is designed and fabricated *** has the standardΛ-shaped negative resistance I-V characteristics as well as a level and smooth valley region that the conventional RSTT *** negative resistance parameters can be varied by changing gate voltage(VGS).For example,the PVCR varies from 2.1 to 10.6 while VGS changes from 0.6 V to 1.0 *** transconductance for IP(ΔIP=ΔVGS)is 0.3 *** parameters of VP,VV and threshold gate voltage(VT)for negative resistance characteristics arising are all smaller than the value reported in the ***,this device is suitable for low dissipation power application.

关键词： real space transfer transistor(RSTT) high speed compound three terminal function device three terminal negative resistance device hot electron device electron transfer device

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发酵乳后酸化的影响因素及其控制措施

食品研究与开发 2024年第4期45卷 200-208页

作者：朱曼李宝磊侯保朝洪维錬何剑张宇姜毓君满朝新东北农业大学食品学院乳品科学教育部重点实验室黑龙江哈尔滨150030 国家乳业技术创新中心上海201111

发酵乳因其独特的口感及较高的营养价值备受消费者的青睐,但由于微生物残余的代谢活性导致发酵乳出现后酸化现象,使其在冷链运输、储存及销售过程中品质急剧下降,菌株稳定性显著降低,严重影响消费者对产品的接受度,并且缩短产品的货架... 详细信息

发酵乳因其独特的口感及较高的营养价值备受消费者的青睐,但由于微生物残余的代谢活性导致发酵乳出现后酸化现象,使其在冷链运输、储存及销售过程中品质急剧下降,菌株稳定性显著降低,严重影响消费者对产品的接受度,并且缩短产品的货架期。因此,该文探讨影响发酵乳后酸化的因素(包括发酵剂的类型、乳的成分、加工参数、益生菌和益生元),对发酵乳后酸化的产生机制进行讨论,并从物理、化学和生物方面综述控制发酵乳后酸化的措施,讨论相关技术的局限性,以期为减弱发酵乳的后酸化程度,改善发酵乳的货架期品质提供参考途径。

关键词：发酵乳酸奶后酸化影响因素产生机制控制措施

Corrosion damage assessment and monitoring of large steel space structures

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Frontiers of Structural and Civil Engineering 2010年第3期4卷 354-369页

作者： Bo CheN You-Lin XU weilian QU Key Laboratory of Roadway Bridge and Structural Engineering Wuhan University of TechnologyWuhan 430070China Department of Civil and Structural Engineering The Hong Kong Polytechnic UniversityHong KongChina

Large steel space structures,when exposed to a harsh corrosive environment,are inevitably subjected to atmospheric corrosion and stress corrosion *** paper proposes a framework for assessing the corrosion damage of large steel space structures subjected to both stress corrosion cracking and atmospheric *** empirical model for estimating atmospheric corrosion based on measured information is briefly *** proposed framework is applied to a real large steel space structure built in the southern coastal area in China to assess its corrosion damage and investigate the effects of atmospheric corrosion on stress corrosion *** on the results,the conceptual design of the corrosion monitoring system of large steel space structures is finally conducted as the first step for a real corrosion monitoring system.

关键词： large steel space structure atmospheric corrosion stress corrosion cracking corrosion damage damage assessment monitoring system

Research advances in the formation poredynamics of sedimentary basins

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Petroleum Research 2017年第2期2卷 107-130页

作者： Zhen Liu Di Sun weilian Li Mingjie Liu Lu Xia Jingjing Liu State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China School of Geoscience and Technology Southwest Petroleum UniversitySichuan 610500China Sinopec Petroleum Exploration&Production Research Institute Beijing 100083China

In the 21st century,the geodynamics is developing towards quantitative ***,due to the irreversible geological processes,it was very difficult to recover the geological *** particular,the restoration of geological parameter evolution process at the microscopic scale has become a major scientific problem in geology ***,a concept of the formation poredynamics is revised and proposed,and the formation poredynamics is a fundamental discipline which focus on the mechanical characteristic of porous media,the pore evolution law,the dynamic genesis and the seepage property of pore fluid during the burial process of clastic ***,it is a new interdiscipline of underground diagenetic dynamics and pore fluid dynamics,and also is as an important part of sedimentary basin *** advances were made in both basic theory and applied *** advances in the basic theory include:(1)the static equilibrium principle of the formation pore,(2)the porosity evolution mechanism and quantitative model of sandstone during the burial diagenetic process,(3)the compaction characteristic and the porosity evolution quantitative model of mudstone,(4)the theoretical relationship between the underground pore fluid temperature and the pore fluid pressure,(5)the influence of the tectonism-induced additional geostress on the pore fluid pressure,and(6)the relationship between the mudstone compaction and the vitrinite reflectance(R_(o))of organic *** advances in the applied research include:(1)the geotemperature-geopressure system division of the sedimentary basin and the interpretation of the hydrocarbon distribution dynamic,(2)the modification of the strata pressure prediction model,(3)the construction of the reservoir critical properties and the reservoir dynamics evaluation system,(4)the simulation of the evolution process of the formation fluid pressure,(5)the numerical simulation and physical experimental simulation on the sandstone

关键词： Formation Poredynamics Geotemperature Geopressure Porosity Critical property of sandstone reservoir Hydrocarbons charging Sedimentary basin

Bulk single crystal growth of SiGe by PMCZ method

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Rare Metals 2003年第3期22卷 197-201页

作者： ZHANG weilian, NIU Xinhuan, CheN Hongjian, ZHANG Jianxin, SUN Junsheng, and ZHANG EnhuaiSemiconductor Material Institute, hebei University of Technology, Tian jin 300130, China Semiconductor Material Institute Hebei University of Technology 天津 300130

A new type of magnetic device was used to replace the conventionalelectro-magnetic field for CZSi (doped with Ge) growth. The device was composed of three permanentmagnetic rings and called PMCZ device. The lines of magnetic force are horizontally distributed atradial 360℃. Using the ring permanent magnetic field, thermal convection in melt and centrifugalpumping flows due to crystal rotation could be strongly suppressed so that the fluctuations oftemperature and micro-growth rate at solid/liquid interface could be restrained effectively. In thePMCZ condition, the growing environment of SiGe bulk single crystal was similar to the crystalgrowth in space under the condition of micro-gravity. The motion of impurities (Ge, oxygen, etc.)had been controlled by diffusion near the solid/liquid interface. Oxygen concentration became lowerand the distribution of composition became more homogeneous along longitudinal direction and acrossa radial section in the grown SiGe crystal. The mechanism of PMCZ superior to MCZ was alsodiscussed.

关键词： SiGe single crystal composition homogeneous PMCZ thermal convection crystal growth

PCB的铜表面粗糙度对高频区域信号传输损失的影响

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印制电路信息 2024年第2期32卷 7-13页

作者：吴熷坤杨梓新徐豪黄李海许伟廉博敏电子股份有限公司广东梅州514000

为了处理电子系统中的大量数据,需要在印制电路板(PCB)上进行高速信号传输,因此减少PCB上的信号损耗变得尤为重要。对PCB上铜线的信号传输损耗进行了研究,通过不同的走线设计,采用不同的介质材料和5种不同的铜箔制作测试板,并采用矢量... 详细信息

为了处理电子系统中的大量数据,需要在印制电路板(PCB)上进行高速信号传输,因此减少PCB上的信号损耗变得尤为重要。对PCB上铜线的信号传输损耗进行了研究,通过不同的走线设计,采用不同的介质材料和5种不同的铜箔制作测试板,并采用矢量网络分析仪测试获得相应数据。根据电磁理论将总信号损耗定量分为介质损耗和导体损耗,针对铜箔表面粗糙度引起的散射损失进行了详细的研究,并证明了低表面粗糙度铜箔的实用性。

关键词： PCB 信号传输铜箔表面粗糙度信号损耗

Growth of Czochralski silicon under magnetic field

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Science China(Technological Sciences) 2004年第3期47卷 281-292页

作者： XU Yuesheng LIU Caichi WANG Haiyun ZHANG weilian YANG Qingxin LI Yangxian REN Binyan LIU Fugui Institute of Information Function Materials Hebei University of Technology Tianjin 300130 China

Growth of Czochralski (CZ) silicon crystals under the magnetic field induced by a cusp-shaped permanent magnet of NdFeB has been investigated. It is found that the mass transport in silicon melt was controlled by its diffusion while the magnetic intensity at the edge of a crucible was over 0.15 T. In comparison with the growth of conventional CZ silicon without magnetic field, the resistivity homogeneity of the CZ silicon under the magnetic field was improved. Furthermore, the Marangoni convection which has a significant influence on the control of oxygen concentration was observed on the surface of silicon melt. It is suggested that the crystal growth mechanism in magnetic field was similar to that in micro-gravity if a critical value was reached, named the growth of equivalent micro-gravity. The relationship of the equivalent micro-gravity and the magnetic intensity was derived as g=(v0/veff)g0. Finally, the orders of the equivalent micro-gravity corresponding to two crucibles with characteristic sizes were calculated.

关键词： Magnetic field equivalent micro-gravity diffusion-controlled mechanism Marangoni convection.

手术室护士应用压力性损伤评估量表促进及障碍因素的质性研究

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中国护理管理 2024年第6期24卷 867-871页

作者：蒋维连刘琳娜梁菡王秀梅陈娟廖芯卢秀英彭俊华桂林医学院第二附属医院手术室广西壮族自治区桂林市541199 青岛市市立医院东院麻醉手术科山西白求恩医院手术室青海省人民医院手术室四川大学华西第二医院手术室四川省肿瘤医院手术室遵义市第一人民医院手术室

目的:基于护士视角,探索应用术中获得性压力性损伤评估量表的促进与障碍因素,为临床提升压力性损伤评估质量提供借鉴。方法:采用描述性质性研究方法,以理论域框架为理论指导制定访谈提纲,选取广西、山东、山西、四川、贵州的6家三级甲... 详细信息

目的:基于护士视角,探索应用术中获得性压力性损伤评估量表的促进与障碍因素,为临床提升压力性损伤评估质量提供借鉴。方法:采用描述性质性研究方法,以理论域框架为理论指导制定访谈提纲,选取广西、山东、山西、四川、贵州的6家三级甲等医院的11名手术室护士进行半结构式深入访谈,采用定向内容分析法归纳并提炼主题。结果:促进因素包括临床需求强、量表的可行性好、量表的权威性强;障碍因素包括环境限制、护士缺乏信心、护士间行为存在差异、医院信息系统智能性欠佳、患者参与不足。结论:手术室护士在应用量表评估过程中既有促进因素,也存在一定障碍因素,应重视量表的实践意义,完善培训、护理流程及辅助工具,推进量表的临床应用。

关键词：压力性损伤手术理论域框架促进因素障碍因素质性研究