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Comparison of capability of time integration methods in capturing dynamic loading

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Earthquake Engineering and Engineering Vibration 2010年第3期9卷 409-423页

作者： Shuenn-Yih Chang chi-wei Hsu Department of Civil Engineering Taipei University of Technology

Numerical properties of the time integration method proposed by the first author of this paper in 2007 are the same as those of the constant average acceleration method （AAM） for linear elastic systems, except that the capability to capture dynamic loading was not explored. It was found that there were different quadrature equations to predict the next step displacement increment. A modified quadrature equation of this method was derived so that the equation to determine the next step displacement was numerically equivalent to the equation used in the constant AAM. It was verified that the original form of this method, in general, had a better capability to capture dynamic loadings than the constant AAM. This excellent property, in addition to computational efficiency, will help to make this method competitive with general secondorder accurate integration methods.

关键词： equations of motion quadrature equation constant average acceleration method integration methods

Re-delineating mountainous areas with three topographic parameters in Mainland Southeast Asia using ASTER global digital elevation model data

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Journal of Mountain Science 2018年第8期15卷 1728-1740页

作者： XIAO chi-wei LI Peng FENG Zhi-ming Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences

Tropical mountainous areas not only provide substantial carbon storage and play an important role in global biological diversity, but also provide basic livelihood for a large number of poor ethnic minorities. However, there is no unified and explicit definition for mountainous areas. The local elevation range(LER) is a crucial structural parameter for delineating mountainous areas. However, current LER products are limited by the subjective selection of an optimum statistical window or coarser spatial resolution of topographical data. In this study, we presented an approach using thresholds for three topographic parameters, elevation, slope, and LER, derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM) to redelineate the vast mountainous areas of mainland Southeast Asia(MSEA). The mean change-point analysis method was applied to determine the optimum statistical window of the 1 arc second(approximately 30 m)-resolution GDEM LER. The results showed that: First, the optimum statistical window is 38 × 38 cell units(width × height) in a rectangular neighborhood, or an area of about 1.30 km^2 for calculating GDEM LER in MSEA. Second, the LER of more than 80% of the area ranges from 30 m to 499 m in MSEA. The LERs in the northern and northwestern MSEA are greater than their counterparts in the south and east. Third, the area of the re-delineated mountainous areas was 83.52 × 10~4 km^2, about 38.71% of the total area. Spatially, the mountainous areas are mainly distributed in the north and northeast of MSEA. The re-delineated 30-m resolution map of the mountainous areas will serve as a topographical dataset for monitoring mountainrelated land surface changes in MSEA. The parameter-modified mountain extraction procedure can be expanded to delineate global mountainous areas.

关键词： Mountainous areas Local elevation range (LER) Statistical analysis Global digital elevation model Mainland Southeast Asia(MSEA)

Iridium(Ⅲ)-catalyzed two-fold C-H alkylation of BINOLs with allyl alcohols

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Organic Chemistry Frontiers 2022年第2期9卷 471-475页

作者： Hao Liu wei chi Meng-Ling Lin Lin Dong Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Ir(Ⅲ)-Catalyzed C-H alkylation of BINOL units has been well examined by using allyl alcohols as coupling *** the advantage of the pyridine guiding group,the efficient protocol allows the rapid synthesis of diverse BI... 详细信息

关键词： alcohols allyl

Photosynthetic Properties of Photosystem Ⅱ in Arabidopsis thaliana Ipa1 Mutant

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Journal of Integrative Plant Biology 2006年第12期48卷 1424-1430页

作者： Lian-wei Peng Jin-Kui Guo Jin-Fang Ma wei chi Li-Xin Zhang Key Laboratory of Arid and Grassland Ecology School of Life Sciences Lanzhou University Lanzhou 730000 China Key Laboratory of Photosynthesis and Environmental Molecular Physiology Photosynthesis Research Center Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

In a previous study, we characterized a high chlorophyll fluorescence Ipal mutant of Arabidopsis thallana, in which approximately 20% photosystem （PS） Ⅱ protein is accumulated. In the present study, analysis of fluorescence decay kinetics and thermoluminescence profiles demonstrated that the electron transfer reaction on either the donor or acceptor side of PSII remained largely unaffected in the Ipa1 mutant. In the mutant, maximal photochemical efficiency （Fv/Fm, where Fm is the maximum fluorescence yield and Fv is variable fluorescence） decreased with increasing light intensity and remained almost unchanged in wildtype plants under different light conditions. The Fv/Fm values also increased when mutant plants were transferred from standard growth light to low light conditions. Analysis of PSll protein accumulation further confirmed that the amount of PSll reaction center protein is correlated with changes in Fv/Fm in Ipal plants. Thus, the assembled PSll in the mutant was functional and also showed increased photosensitivity compared with wild-type plants.

关键词： Arabidopsis thaliana electron transfer Ipa1 photosensitivity photosystem Ⅱ.

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人工智能时代：智能眼科发展的关键问题思考

国际眼科杂志 2025年第1期25卷 13-16页

作者：杨卫华许言午迟玮中国广东省深圳市眼科医院深圳市眼病防治研究所华南理工大学未来技术学院人工智能与数字经济广东省实验室(广州)

智能眼科研究在近年来迅速发展，其临床应用或临床转化过程中仍然存在一些挑战。智能眼科发展过程中，两个亟待解决的重要问题就是：推进临床应用和维护医疗公平。针对上述问题，文章分析了智能眼科临床应用推进的不足和潜在医疗公平的... 详细信息

智能眼科研究在近年来迅速发展，其临床应用或临床转化过程中仍然存在一些挑战。智能眼科发展过程中，两个亟待解决的重要问题就是：推进临床应用和维护医疗公平。针对上述问题，文章分析了智能眼科临床应用推进的不足和潜在医疗公平的挑战这两个方面的原因和现状，提出了推进临床应用和维护医疗公平智能眼科发展的关键问题，同时系统提出了相应的具体措施，以促进智能眼科的发展。

关键词：人工智能智能眼科临床应用医疗公平发展

糖尿病足伴慢性骨髓炎大鼠模型建立的分析与展望

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动物医学进展 2025年第1期46卷 109-113页

作者：焦琳茜徐旭英张博蔺莉马逸朝刘威池首都医科大学附属北京中医医院北京100010

糖尿病足伴慢性骨髓炎是一种常见的糖尿病并发症,具有较高的截肢率及致死率,目前缺乏可靠的治疗手段。建立成熟的糖尿病足伴慢性骨髓炎模型可促进治疗手段的进一步研发。根据糖尿病和骨髓炎各自的类型及成因,已有多种造模方法供研究选择... 详细信息

糖尿病足伴慢性骨髓炎是一种常见的糖尿病并发症,具有较高的截肢率及致死率,目前缺乏可靠的治疗手段。建立成熟的糖尿病足伴慢性骨髓炎模型可促进治疗手段的进一步研发。根据糖尿病和骨髓炎各自的类型及成因,已有多种造模方法供研究选择,但目前尚未出现关于糖尿病足骨髓炎动物模型的研究报道。论文就骨髓炎模型以及糖尿病模型制备方法方面的研究进展进行综述,提出了建立糖尿病足伴慢性骨髓炎大鼠模型方法,并分析各类模型的优缺点,旨在为建立一种用于研究糖尿病足骨髓炎的动物模型奠定基础。

关键词：糖尿病足伴慢性骨髓炎糖尿病骨髓炎动物模型大鼠

Electrodeposition and characterization of thermoelectric Bi_2Se_3 thin films

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 104-107页

作者： Xiao-long Li Ke-feng Cai Hui Li Ling Wang chi-wei Zhou Functional Materials Research Laboratory Tongji University Shanghai 200092 China

Bi2Se3 thin films were electrochemically deposited on Ti and indium tin oxide-coated glass substrates, respectively, at room temperature, using Bi（NO3）3·5H2O and SeO2 as starting materials in diluted HNO3 solution. A conventional three-electrode cell was used with a platinum sheet as a counter electrode, and a saturated calomel electrode was used as a reference electrode. The films were annealed in argon atmosphere. The influence of cold isostatic pressing before annealing on the microstructure and thermoelectric properties of the films was investigated. X-ray diffraction analysis indicates that the film grown on the indium tin oxide-coated glass substrate is pure rhombohedral Bi2Se3, and the film grown on the Ti substrate consists of both rhombohedral and orthorhombic Bi2Se3.

关键词： thermoelectric thin films bismuth selenide electrodeposition thermoelectric properties cold isostafic pressing

Evaluating the suitability of different terrains for sustaining human settlements according to the local elevation range in china using the ASTER GDEM

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Journal of Mountain Science 2018年第12期15卷 2741-2751页

作者： XIAO chi-wei FENG Zhi-ming LI Peng YOU Zhen TENG Jia-kun Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences

The topographical suitability assessment of human settlements(SAHS) creates a solid foundation for regional population distribution and socio-economic development. Local elevation range(LER) is an important factor that can be used to assess the suitability of different terrains for sustaining human settlements. However, current digital elevation model(DEM)-based LER products suffer from some challenges typically because of their subjectively selected neighborhood scales and coarser spatial resolution. In this study, we initially determined the optimal statistical window and then calculated the appropriate LER with the finer resolution data of the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global DEM(ASTER GDEM) products for china. Then, the appropriate LER was used to evaluate the topographical SAHS and its correlations with the national gridded population distribution(1 km × 1 km) in 2010. The results show that the optimal statistical window for calculating a 1 arc-second(about 30 m) resolution GDEM LER for china can be determined using a 51 × 51 grid unit(width × height) within a rectangular neighborhood, corresponding to an area of about 2.34 km^2. Secondly, the LER values in the southern and western china were greater than those of the north and east, showing a trend which consistently reflects the general spatial features of landforms. Finally, the relationship between GDEM LER and population density was highly correlated with the R^2 value of 0.81. It showed that 85.22% of the chinese population was located in areas where the LER is lower than 500 m. The topographically suitable area within china decreased from the southeastern coastal zone towards the northwestern inland areas due to transition from plains and basins to plateaus and mountains. The total area of moderate to high suitable level was 423.84 × 10~4 km^2, or 44.15% of the total land area, with 88.17% of the national population. Our study demonstrates the usefulness of appropriat

关键词： Human settlements Topographical suitability Local elevation range (LER) Advanced Spaceborne Thermal Emission and Reflection Radiometer Global DEM (ASTER GDEM) china

Synthesis and Characterization of Linked Clusters Capped by Alkylidyne

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chinese Journal of Structural Chemistry 2002年第1期21卷 17-21页

作者： ZHANG Yu-Hua chi wei-Guang YIN Yuan-Qi HUANG Zi-Xiang WU Qiang-Jin State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002China 不详

The lsolobal displacement reaction between the dianion {M(CO)3[(h5-C5H4) C(O)C6H4C(O)(h5-C5H4)](CO)3M}2- and two molecules of [(m3-C)CO2Et]Co3(CO)9 gave rise to the formation of terephthaloyl(biscyclopentadienyl)-bridged double cluster complexes [(h5-C5H4)C(O)C6H4C(O)(h5-C5H4)]{[(m3-C)CO2Et]Co2M(CO)8}2 (M = Mo 1, M = W, 2). In the reaction, single cluster complexes[(m3-C)CO2Et]-Co2M(CO)8[h5-C5H4C(O)C6H4CO2CH3] ( M = Mo 3, M = W, 4) were yielded as by-products. All the cluster complexes were characterized by C/H analysis, IR and 1H NMR spectroscopy, and the structure of 3 has been determined by single-crystal X-ray diffraction method. Crystal data: Mr = 750.19, monoclinic, space group P21/c, a = 22.652(5), b = 8.954 (2), c = 14.530(3) ? b = 104.00(3), V = 2859.6(10) 懦, Z = 4, Dc = 1.743 mg/m? F(000) = 1488, m = 1.644 mm-1, the final R = 0.0555 and wR = 0.1353 for 5519 observations with I > 2s(I).

关键词： transition metal linked cluster crystal structure cobalt