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Landslide Susceptibility Mapping by Using Landslide RatioBased Logistic Regression:A Case Study in the Southern Taiwan

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Journal of Mountain Science 2015年第3期12卷 721-736页

作者： wu chun-Hung Department of Water Resources Engineering and Conservation Feng Chia University

The object of the research is to compare the model performance and explain the error source of original logistic regression landslide susceptibility model(abbreviated as or-LRLSM) and landslide ratio-based logistic regression landslide susceptibility model(abbreviated as lr-LRLSM) in the Chishan watershed with a serious landslide disaster after 2009 Typhoon Morakot. The landslide inventory induced by 2009 Typhoon Morakot in South Taiwan is the main research material, while the Chishan watershed is the research area. Six variables, including elevation, slope, aspect, geological formation, accumulated rainfall, and bank erosion, were included in the two models. The performance of lr-LRLSM is better than that of or-LRLSM. The Cox & Snell R2, Nagelkerke R2 value, and the area under the relative operating characteristic curve(abbreviated as AUC) of lrLRLSM is larger than those of or-LRLSM, and the average correct ratio for the lr-LRLSM to predict landslide or non-landslide is larger than that of orLRLSM by 5.0%. The increase of the average correct ratio(abbreviated as ACR) difference from or-LRLSM to lr-LRLSM shows in slope, revised accumulated rainfall, aspect, geological formation and bank erosion variables, and only light decreases in elevation variable. The error sources of continuous variables in building the or-LRLSM is the dissimilarity between the distribution of landslide ratio and production of coefficient and characteristic values, while those of categorical variables is due to low correlation of landslide ratio and the coefficient value of each parameter. Using the classification of landslide ratio as the database to build logistic regression landslide susceptibility model(abbreviated as LRLSM) can revise the errors. The comparison of or-LRLSM and lr-LRLSM in the Chishan watershed also shows that building the landslide susceptibility model(abbreviated as LSM) by using lr-LRLSM is practical and of better performance than that by using the or-LRLSM.

关键词： Logistic regression Landslidesusceptibility Landslide ratio Chishan watershed Typhoon Morakot

Analysis of sliding electric contact characteristics in augmented railgun based on the combination of contact resistance and sliding friction coefficient

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Defence Technology（防务技术） 2020年第4期16卷 747-752页

作者： chun-yan Zhu Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyChina

The contact resistance between the armature and rails is an important indicator of the contact characteristics in electromagnetic *** the contact resistance depends not only on the contact state but also on the contact stress and temperature,there are some limitations in analyzing the contact characteristics using only the contact *** this paper,the contact characteristics of the augmented railgun are analyzed by the combination of contact resistance and sliding friction ***,the theoretical calculation model of the contact resistance and friction coefficient of the augmented electromagnetic railgun is *** the contact resistance and friction coefficient are calculated by the measured values of the muzzle voltage,rail current and armature ***,the contact characteristics are analyzed according to the features of the waveforms of the contact resistance and the friction coefficient,and the analysis conclusions are verified by experimental rail *** results showed that:the aluminum melt film gradually formed on the contact surface reduces the contact resistance and the friction coefficient;the wear and erosion of the armature cause deterioration of the contact state;after the transition,the reliability of the sliding contact between the armature and rails decreases,resulting in an increase in contact resistance.

关键词： Augmented railgun Contact resistance Friction coefficient Contact characteristics

Investigation on the interface of Cu/Al couples during isothermal heating

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International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 309-318页

作者： yan-qiu Han Li-hua Ben Jin-jin Yao Shu-wei Feng chun-jing wu School of Materials Science and Engineering University of Science and Technology Beijing

The evolutionary process and intermetallic compounds of Cu/A1 couples during isothermal heating at a constant bonding tem- perature of 550℃ were investigated in this paper. The interracial morphologies and microstructures were examined by optical microscopy, scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, and X-ray diffraction. The results suggest that bonding is not achieved between Cu and A1 at 550℃ in 10 min due to undamaged oxide films. Upon increasing the bonding time from 15 to 25 min, however, metallurgical bonding is obtained in these samples, and the thickness of the reactive zone varies with holding time. In the interfacial region, the final microstructure consists of Cu9A14, CuAl, CuA12, and ct-A1 ＋ CuAl2. Furthermore, these results provide new insights into the mechanism of the imerfacial reaction between Cu and A1. Microhardness measurements show that the chemical composition exerts a signifi- cant influence on the mechanical properties of Cu/A1 couples.

关键词： copper aluminum intermetallic compounds oxide films isothermal heating

基于虚拟仪器技术的海上实时自动调平系统设计

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船海工程 2009年第2期38卷 125-128页

作者：陈建民蔡淳鹏刘彦武中国石油大学(华东)石油工程学院山东青岛266555

考虑浮式平台及船舶在波浪作用下的摇摆,设计一种适合于海上摇摆环境下使用的液压自动调平平台。基于虚拟仪器技术与液压技术的有机结合,系统的硬件组成及控制的复杂程度得到简化,通过液压缸腿的逆摇摆运动实现实时地自动调平,为海上生... 详细信息

考虑浮式平台及船舶在波浪作用下的摇摆,设计一种适合于海上摇摆环境下使用的液压自动调平平台。基于虚拟仪器技术与液压技术的有机结合,系统的硬件组成及控制的复杂程度得到简化,通过液压缸腿的逆摇摆运动实现实时地自动调平,为海上生活及作业提供无摇摆的"陆地"环境。

关键词：摇摆虚拟仪器液压自动调平 LabVIEW

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驱动合成气压缩机用工业汽轮机设计分析

机电工程 2016年第10期33卷 1213-1216,1267页

作者：郑飞逸何大江陈锋牛春燕林炯吴腾杭州汽轮机股份有限公司浙江杭州310022

针对某化工企业用合成气汽轮机高参数、高转速、高功率等要求的问题,基于透平热力学理论,提出了一种反动式工业汽轮机设计方案。使用透平强度理论对汽轮机直叶片的应力进行了详细计算,使用有限元分析对调节级叶片、末级扭叶片的应力进... 详细信息

针对某化工企业用合成气汽轮机高参数、高转速、高功率等要求的问题,基于透平热力学理论,提出了一种反动式工业汽轮机设计方案。使用透平强度理论对汽轮机直叶片的应力进行了详细计算,使用有限元分析对调节级叶片、末级扭叶片的应力进行了详细研究,使用转子动力学理论对汽轮机转子4种不同振型的不平衡响应振动进行了详细分析。利用动平衡机对转子进行了高速动平衡试验,同时通过汽轮机空负荷试验,检查了转子的实际振动情况。试验结果表明,汽轮机的功率与转速均满足用户的要求,叶片的应力在许用范围之内,叶片强度满足要求,转子的临界转速具有足够的避开余量,转子的振幅不超过25μm,符合API612的要求;该设计方案可满足用户的要求,能广泛满足合成气压缩机的驱动需求。

关键词：工业汽轮机叶片强度分析转子动力学

Mechanisms of Cytochrome C Extraction by Reverse Micelles

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Chemical Research in Chinese Universities 2001年第1期17卷 73-76页

作者： YU yan chun QIAN Bao hua CHU Ying wu Zi sheng GAO Chang qing Department of Chemical Engineering Huaihai Institute of TechnologyLianyungang 222005P.R.China Department of Chemistry Northeast Normal UniversityChangchun 130024P.R.China

The extraction of cytochrome C was carried out by means of phase transfer technique with three different reverse micellar systems, i.e. , a CTAB micellar solution in n butyl alcohol chloroform(volume ratio 4∶1), an AOT micellar solution in isooctane and a SDSS D 2EHPA micellar solution in isooctane. The extraction mechanisms were studied. The results show that the extraction mechanisms for the same proteins with different types of reverse micellar systems can be distinct. The extraction of cytochrome C with CTAB and SDSS D 2EHPA reverse micellar systems are carried out according to the mechanism of electrostatic interaction. However, in the extraction of cytochrome C with the AOT reverse micellar system, the electrostatic interaction between the protein and the surfactant is not important.

关键词： Mechanism Cytochrome C Extraction Reverse micelles

Synthesis and antitumor activity of nitric oxide releasing derivatives of AT1 antagonist

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Chinese Chemical Letters 2009年第3期20卷 302-305页

作者： yan chun Zhang Jin Pei Zhou Xiao Ming wu Wei Hong Pan Department of Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

A series of novel nitric oxide-donating derivatives （7a-e, 8a-e） were synthesized by coupling furoxan and nitric oxide with irbesartan analogue and their cytotoxicity against BEL7402 cells in vitro were evaluated by MTT method. It was found that 8c exhibits the most cytotoxic activities with ICso value of 12.5 μmol/L. The hybrids of AT1 antagonist and nitric oxide donor appear to have beneficial effects on antitumor.

关键词： AT1 antagonist Nitric oxide-donating Antitumor Synthesis

Fabricating Na/In/C Composite Anode with Natrophilic Na-In Alloy Enables Superior Na Ion Deposition in the EC/PC Electrolyte

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Nano-Micro Letters 2022年第2期14卷 45-59页

作者： Hui Wang yan wu Ye Wang Tingting Xu Dezhi Kong yang Jiang Di wu Yongbing Tang Xinjian Li chun-Sing Lee Key Laboratory of Material Physics of Ministry of Education School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052People’s Republic of China Department of Chemistry Center of Super‑Diamond and Advanced Films(COSDAF)City University of Hong KongHong Kong SAR 999077People’s Republic of China School of Materials Science and Engineering Hefei University of TechnologyHefei 230009AnhuiPeople’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055People’s Republic of China

In conventional ethylene carbonate(EC)/propylene carbonate(PC)electrolyte,sodium metal reacts spontaneously and deleteriously with solvent *** significantly limits the practical feasibility of high-voltage sodium metal batteries based on Na metal ***,we present a sodium metal alloy strategy via introducing NaIn and Na_(2)In phases in a Na/In/C composite,aiming at boosting Na ion deposition stability in the common EC/PC *** cells with Na/In/C electrodes achieve an impressive long-term cycling capability at 1 mA cm^(-2)(>870 h)and 5 mA cm^(-2)(>560 h),respectively,with a capacity of 1 mAh cm^(-2).In situ optical microscopy clearly unravels a stable Na ion dynamic deposition process on the Na/In/C composite electrode surface,attributing to a dendrite-free and smooth ***,theoretical simulations reveal intrinsic mechanism for the reversible Na ion deposition behavior with the composite Na/In/C *** pairing with a highvoltage NaVPOF cathode,Na/In/C anode illustrates a better suitability in SMB *** work promises an alternative alloying strategy for enhancing Na metal interfacial stability in the common EC/PC electrolyte for their future applications.

关键词： EC/PC electrolyte Sodium metal batteries Na/In/C electrode Dendrite-free and smooth morphology Theoretical simulations

A DEM upscaling method with integrating valley lines based on HASM

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Frontiers of Earth Science 2024年第3期18卷 509-525页

作者： Mingwei ZHAO Xiaoxiao JU Na ZHAO chun WANG yan XU Xiaoran wu Weitao LI Geographic Information and Tourism College Chuzhou UniversityChuzhou 239000China College of Resource Environment and TourismCapital Normal UniversityBeijing 100048China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100101China Anhui Engineering Laboratory of Geo-information Smart Sensing and Services Chuzhou 239000China Anhui Center for Collaborative Innovation in Geographical Information Integration and Application Chuzhou 239000China School of Geographic Information and Tourism Chuzhou UniversityChuzhou 239000China

A new digital elevation model(DEM)upscaling method based on high accuracy surface modeling(HASM)is proposed by combining the elevation information of DEM and the valley lines extracted from DEM with different flow accumulation *** proposed method has several advantages over traditional DEM upscaling ***,the HASM ensures the smoothness of the upscaled ***,several DEMs with different topographic details can be obtained using the same DEM grid size by incorporating the valley lines with different flow accumulation *** Jiuyuangou watershed in China’s Loess Plateau was used as a case study.A DEM with a grid size of 5 m obtained from the local surveying and mapping department was used to verify the proposed DEM upscaling *** established the surface complexity index to describe the complexity of the topographic surface and quantified the differences in the topographic features obtained from different upscaling *** results show that topography becomes more generalized as grid size and flow accumulation threshold *** a large DEM grid size,an increase in the flow accumulation threshold increases the difference in elevation values in different grids,increasing the surface complexity *** study provides a new DEM upscaling method suitable for quantifying topography.

关键词： DEM upscaling HASM flow accumulation threshold surface complexity index