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COUPLED VIBRATION OF STRUCTURAL THIN-WALLED CORES

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Acta Mechanica Solida Sinica 2000年第1期13卷 81-88页

作者： Shiu Cho ng j.S.Kuang Department of Civil Engineering Hong Kong University of Science and Technology

This paper presents an analysis of the coupled vibration of asymmetric core structures in tall buildings. The governing equation of free vibration and its corresponding eigenvalue problem, which is a set of equations for laterally flexural vibrations in two different directions coupled by a warping-St. Venant torsional vibration, are derived. Based on the Calerkin method, a generalized approximate method is developed for the analysis of coupled vibration and thus proposed for determining the natural frequencies and mode shapes of the structure in triply-coupled vibration. The results of the proposed method for the example structure show good agreement with those of the FEM analysis. The proposed method has been shown to provide a simple and rapid, yet accurate, means for coupled vibration analysis of core structures.

关键词： coupled vibration analysis asymmetric core structure Galerkin method natural frequency mode shape

Ranking parameters in urban energy models for various building forms and climates using sensitivity analysis

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Building Simulation 2023年第9期16卷 1587-1600页

作者： Aysegul Demir Dilsiz Kaitlynn ng jérôme Kämpf Zoltan Nagy Department of Civil and Architectural Engineering and Construction Management University of WyomingLaramie WYUSA Intelligent Environments Lab Department of CivilArchitectural and Environmental EngineeringThe University of Texas at AustinAustin TXUSA Energy Informatics Group Idiap Research Institute1920 MartignySwitzerland

Urban Building Energy Modelling(UBEM)allows us to simulate buildings’energy performances at a larger ***,creating a reliable urban-scale energy model of new or existing urban areas can be difficult since the model requires overly detailed input data,which is not necessarily publicly *** calibration is a necessary step to reduce the uncertainties and simulation results in order to develop a reliable and accurate *** to the concerns over computational resources and the time needed for calibration,a sensitivity analysis is often required to identify the key parameters with the most substantial impact before the calibration is deployed in ***,we study the sensitivity of uncertain input parameters that affect the annual heating and cooling energy demand by employing an urban-scale energy model,*** goal is to determine the relative influence of each set of input parameters and their interactions on heating and cooling loads for various building forms under different ***,we conduct a global sensitivity analysis for annual cooling and heating consumption under different climate *** upon this,we investigate the changes in input sensitivity to different building forms,focusing on the indices with the largest Total-order ***,we determine First-order indices and Total-order effects of each input parameter included in the urban building energy *** also provide tables,showing the important parameters on the annual cooling and heating demand for each climate and each building *** find that if the desired calibration process require to decrease the number of the inputs to save the computational time and cost,calibrating 5 parameters;temperature set-point,infiltration rate,floor U-value,*** U-value and roof U-value would impact the results over 55%for any climate and any building form.

关键词： global sensitivity analysis Sobol’method urban energy modeling building stocks energy modelling parameter screening Sobol’indices sustainable urban planning

第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇结构和性质的研究

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原子与分子物理学报 2025年第4期42卷 93-99页

作者：张颂程露吴学科凯里学院理学院凯里556011

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明... 详细信息

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明显增大.过渡金属原子与B_(12)N_(12)结合的过程中,除Cu和B原子外,剩余金属与N原子的Mulliken电荷出现负值.另外,金属原子的加入,不仅增加电偶极矩和极化率的值,还促使其红外吸收光谱发生红移.

关键词：团簇结构性质第一性原理

The role of AVDR in linear cascade testing

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航空动力学报 2007年第6期22卷 933-944页

作者： Wing F.ng Department of Mechanical Engineering Virginia Polytechnic Instituteand State University

Linear cascade testing plays an important role in the research and development of turbomachinery and is widely used over the *** ideal cascade model of a turbomachinery blade row is *** actual linear cascade testing,the flow through the test section converges due to the development of the boundary layer and secondary flow along the sidewall surfaces of the test *** velocity density ratio(AVDR) is adopted to account for the deviation of the tested cascade flow from the ideal 2D *** numerous published cascade works,the influence of AVDR on cascade performance is seen to be complicated with many affecting factors,such as those related to cascade/blade geometry and flow ***,controlling AVDR is limited by the facility ***,real blade-to-blade flow in turbomachines is usually associated with AVDR greater than unity due to limited span of blades between the hub and shroud such that cascade testing without reducing AVDR could be favored *** these facets add complexity and diversification to the *** current paper reviews previous studies and results on *** understanding on the role of AVDR and recommendations on how to deal with it in linear cascade testing are provided.

关键词：线性叶栅试验轴向速度密度比空气流动叶栅特性

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碳排放权交易制度的权利逻辑与规范进路

河北大学学报（哲学社会科学版） 2025年第1期50卷 123-134页

作者：柯坚曹辰武汉大学环境法研究所湖北武汉430072

当下我国碳排放权交易制度体系正在经历着由政策引领向法治构建的转变。目前碳排放权交易制度行政立法中简单将“权利”与“配额”等同的做法,既无法体现碳排放权所兼具的公法、私法双重特征,也难以有效回应碳排放权交易市场的发展需求... 详细信息

当下我国碳排放权交易制度体系正在经历着由政策引领向法治构建的转变。目前碳排放权交易制度行政立法中简单将“权利”与“配额”等同的做法,既无法体现碳排放权所兼具的公法、私法双重特征,也难以有效回应碳排放权交易市场的发展需求以及完善碳排放权交易制度的规范构建。为此,需要构建以碳排放权交易市场为语境、以碳排放“权利”为逻辑主线的碳排放权交易制度,夯实其法治基础并明确其规范进路。从语境与语义出发,“碳排放权”的表述本身就意味着其私法的权利属性。在碳排放权交易制度的理论逻辑层面,双阶理论可以为碳排放权交易制度中“配额”到“权利”的过渡提供理论支撑;在其实践逻辑层面,碳排放权交易制度需要借助“权利”的确立为其交易市场的展开提供法治的基础。最后,考虑到碳排放权权利属性共识不足、碳排放权交易制度结构尚待稳定、权利基础呈现多元特征以及权利来源并非稳固不变等因素,策略上可以考虑暂时搁置碳排放权权属争议,以权益为抓手、以“权益表现—适用规范领域—法律保护方式”为主线,分步骤、分阶段推进碳排放权交易制度的规范构建。

关键词：碳排放权权益配额权利逻辑规范进路

Unraveling transition-metal-mediated stability of spinel oxide via in situ neutron scattering

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journal of Energy Chemistry 2022年第5期31卷 60-70页

作者： Yan Chen ke An Neutron Scattering Division Oak Ridge National LaboratoryOak RidgeTN 37831USA

The energy materials performance is intrinsically determined by structures from the average lattice structure to the atom arrangement, valence, and distribution of the containing transition metal(TM) elements. Understanding the mechanism of the structure transition and atom rearrangement via synthesis or processing is key to expediting the exploration of excellent energy materials. In this work, in situ neutron scattering is employed to reveal the real-time structure evolution, including the TM-O bonds, lattice,TM valence and the migration of the high-voltage spinel cathode LiNi_(0.5)Mn_(1.5)O_(4). The transition-metalmediated spinel destabilization under the annealing at the oxygen-deficient atmosphere is *** formation of Mn^(3+) is correlated to the TM migration activation, TM disordered rearrangement in the spinel, and the transition to a layered-rocksalt phase. The further TM interdiffusion and Mn^(3+) reduction are also revealed with multi-stage thermodynamics and kinetics. The mechanisms of phase transition and atom migrations as functions of temperature, time and atmosphere present important guidance on the synthesis in various-valence element containing oxides.

关键词： In situ neutron diffraction Pair distribution function Energy storage material Material synthesis High-temperature phase transition Disordering Atomic interdiffusion

Effect of Hydrogen on Plastic Deformation near Crack-tipof A537 Steel in 3.5%NaCl Solution

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journal of Materials Science & Technology 1996年第3期12卷 227-231页

作者： Wei, Xj Li, j Wang, ZF ke, W State key Lab. of Corrosion and Protection Institute of Corrosion and Protection of Metals Chinese Academy of Sciences Shenyang 110015 China

A computerized digital speckle-interferometry system was set up to study in-situ the influence of cathodic hydrogen charging on the crack opening displacement and on the plastic strain distribution at corrosion fatigue crack tip for the single-edge notched plate specimens of structural steel in 3.5%NaCl solution with an applied potential of -1400 mV (SCE). Meanwhile, the mono-directional tension tests with smooth specimens were performed in both air and 3.5%NaCl solution under the hydrogen charging conditions. The fracture surface morphology from corrosion fatigue and tension was examined by SEM. The experimental results show that the existence of hydrogen in crack tip material caused an increase of both yield strength and hardening exponent and a decrease of plastic zone size at the corrosion fatigue crack tip.

关键词： NaCl Effect of Hydrogen on Plastic Deformation near Crack-tipof A537 Steel in 3.5%NaCl Solution SCE

2011—2020年广州市肺结核死亡趋势及年龄-时期-队列模型分析

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中国防痨杂志 2025年第1期47卷 44-50页

作者：李雪秋刘群唐科吴迪广州市胸科医院结核病防治所一分所广州510095 广东省生物制品与药物研究所药理研究室广州510440 广州市疾病预防控制中心慢性非传染性疾病预防控制部广州510440 广东医科大学公共卫生学院东莞523808

目的:分析2011—2020年广州市肺结核患者的死亡情况和死亡率变化趋势,为制定防控策略和措施提供科学依据。方法:采用joinpoint回归模型分析2011—2020年广州市全年龄段人群肺结核死亡率变化趋势,并计算年度变化百分比(annual percent ch... 详细信息

目的:分析2011—2020年广州市肺结核患者的死亡情况和死亡率变化趋势,为制定防控策略和措施提供科学依据。方法:采用joinpoint回归模型分析2011—2020年广州市全年龄段人群肺结核死亡率变化趋势,并计算年度变化百分比(annual percent change,APC)和平均年度变化百分比(average annual percent change,AAPC);使用年龄-时期-队列模型分析广州市20~85岁人群肺结核死亡风险的年龄、时期和队列效应。结果:广州市2011—2020年报告肺结核死亡患者2144例,年均报告标化死亡率为2.57/10万;男性肺结核标化死亡率为4.19/10万,约为女性标化死亡率(0.96/10万)的4.4倍。10年间广州市肺结核年龄标化死亡率总体呈现下降趋势,AAPC为-4.15%(95%CI:-6.41%~-1.85%,P=0.003);其中,女性肺结核死亡率下降速度高于男性,AAPC分别为-6.72%(95%CI:-10.38%~-2.92%,P=0.004)和-3.55%(95%CI:-6.19%~-0.85%,P=0.017)。在不同年龄段人群中,0~49岁和≥65岁年龄段人群肺结核死亡率均呈现明显下降趋势,AAPC分别为-7.05%(95%CI:-11.52%~-2.34%,P=0.009)和-3.94%(95%CI:-6.22%~-1.62%,P=0.005)。年龄-时期-队列模型的年龄效应显示,随着年龄的增长,肺结核死亡风险不断上升,≥65岁人群尤为显著,发病率由66~67岁年龄组的2.93/10万增长至84~85岁年龄组的6.10/10万。时期效应显示,肺结核死亡风险随着时期的变化总体呈现下降趋势,相对危险度(risk ratio,RR)从2011—2012年时期组的1.35下降至2019—2020年时期组的0.81。队列效应显示,越晚出生的人群肺结核死亡风险越低,RR值从1926—1927年出生队列的5.91降低至1998—1999年出生队列的0.16。结论:广州市肺结核死亡率总体呈不断下降的趋势,但男性和女性肺结核死亡率差距较大。需重点关注男性和≥65岁年龄段的老年人群,并实施针对性的防控和治疗措施。

关键词：结核,肺死亡率回归分析队列研究

Indexing Non-merohedrally Twinned Crystals by Bruker'sAPEX2 and Agilent's CrysAlis^(PRO), an Example of a Crystal Structure That Can Be Refined through Either the PLATONRoute or the ‘HKLF 5' Route, and, Simultaneous Data Collection of Two Crystals in a Two-in-one Run

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Chinese journal of Structural Chemistry 2014年第2期33卷 294-303页

作者： ng Seik Weng Department of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia Chemistry Department King Abdulaziz University

The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPRO was used for processing the frames of bis（diethyldicarbamato）nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [（3-formyl-4- hydroxyphenyl）methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5＇（based on a combined set of diffraction indices） and PLATON（based on one set of diffraction indices） routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{（E）-（4-aminophenyl）diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly.

关键词： merohedral non-merohedral twin APEX2 Crys Alis^PRO two-in-one data collection