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accurate stress analysis on rigid central buckle of long-span suspension bridges based on submodel method

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Science China(Technological Sciences) 2009年第4期52卷 1019-1026页

作者： WANG Hao LI AiQun GUO Tong MA Shuang College of Civil Engineering Southeast UniversityNanjing 210096China

Runyang Suspension Bridge (RSB) with the main span of 1490 m is the longest bridge in China and the third longest one in the world. In this bridge the rigid central buckle is employed for the first time in the mid-span of the suspension bridge in China. For such a super-long-span bridge, the traditional finite element (FE) modeling technique and stress analysis methods obviously cannot satisfy the needs of conducting accurate stress analysis on the central buckle. In this paper, the submodel method is in- troduced and for the first time used in analyzing the stresses of the central buckle. After an accurate FE submodel of the central buckle was specially established according to the analysis results from the whole FE model, the connection technique between the two-scale FE models was realized and the ac- curate stresses of the central buckle under various vehicle load cases were then conducted based on the submodel method. The calculation results were testified to be accurate and reliable by the field measurements, which show the efficiency and reliability of the submodel method on analyzing the mechanical condition of the central buckle of long-span suspension bridges. Finally, the working be- havior and mechanical characteristics of the central buckle of the RSB under vehicle loads were ana- lyzed based on the calculation and measurement results. The results obtained in this paper can provide theoretic references for analyzing and designing the rigid central buckle in long-span suspension bridges in future.

关键词： suspension bridge central buckle accurate stress submodel method field measurements

accurate dependences of spontaneous emission factor, lifetime, and photon lifetime on threshold current

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Optoelectronics Letters 2020年第2期16卷 103-107页

作者：贾凯萍张亮冯列峰 Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology Department of Applied PhysicsTianjin UniversityTianjin 300072China

Using the rate equation, several optical methods of characterizing the threshold of a laser diode(LD) were analyzed. The thresholds determined by all methods are consistent if the spontaneous-emission-coefficient(β) is small. If β>0.05, the thresholds obtained by different methods are different. Especially, for micro-nano LDs with a large β, these methods are starting to become inaccurate. However, the d^2S/dI^2-I is a relatively accurate method to characterize threshold of these LDs compared to other methods. The effects of the spontaneous-emission-lifetime(τsp) and the photon-lifetime(τp) on thresholds were analyzed. The exact functions between the threshold and the β, τsp and τp were obtained.

关键词： lifetime photon accurate

accurate Registration of Remote Sensing Images Based on Local Optimal Transformation

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Journal of Beijing Institute of Technology 2019年第2期28卷 371-382页

作者： Bo Wang Changqing Li Shi Tang Zhiqiang Zhou Hong Zhao School of Automation Beijing Institute of TechnologyBeijing 100081China Beijing Urban Construction Design&Development Group Co. Ltd.Beijing 100071China Beijing Navigation Control Technology Co. Ltd.Beijing 102200China

As the basic work of image stitching and object recognition,image registration played an important part in the image processing field.Much previous work in registration accuracy and realtime performance progressed very slowly,especially in registrating images with line feature.An innovative method for image registration based on lines is proposed,it can effectively improve the accuracy and real-time performance of image registration.The line feature can deal with some registration problems where point feature does not work.Our registration process is divided into two parts.The first part determines the rough registration transformation relation between reference image and test image.Then the similarity degree among different transformation and modified nonmaximum suppression(MNMS)algorithms are obtained,which produce local optimal solution to optimize the rough registration transformation.The final optimal registration relation can be obtained from two registration parts according to the match scores.The experimental results show that the proposed method makes a more accurate registration relation and performs better in real-time situation.

关键词： initial registration relationship accurate registration relationship similarity degree local optimal transformation modified non-maximum suppression(MNMS)algorithm

Real-time accurate hand path tracking and joint trajectory planning for industrial robots(Ⅱ)

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Journal of Central South University of Technology 2002年第3期9卷 273-278页

作者：谭冠政胡生员 College of Information Science and Engineering Central South University

Previously, researchers raised the accuracy for a robot′s hand to track a specified path in Cartesian space mainly through increasing the number of knots on the path and the segments of the path. But, this method resulted in the heavier on line computational burden for the robot controller. In this paper, aiming at this drawback, the authors propose a new kind of real time accurate hand path tracking and joint trajectory planning method for robots. Through selecting some extra knots on the specified hand path by a certain rule, which enables the number of knots on each segment to increase from two to four, and through introducing a sinusoidal function and a cosinoidal function to the joint displacement equation of each segment, this method can raise the path tracking accuracy of robot′s hand greatly but does not increase the computational burden of robot controller markedly.

关键词： industrial robot real-time accurate hand path tracking joint trajectory planning extra knot sinusoidal function cosinoidal function

Development of an accurate nursing program based on function in chronic venous leg ulcers:protocol for matching function status with nursing interventions using the Delphi survey

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Frontiers of Nursing 2018年第4期5卷 265-272页

作者： Yi-Fan Tang Xin-Yu Hu Jing Zhao Ze-Juan Gu Shuang-Shuang Xing Wei-Yun Wang College of Nursing Nanjing Medical University Department of Outpatient Treatment The First Affiliated Hospital with Nanjing Medical University Department of Nursing The First Affiliated Hospital with Nanjing Medical University

Objective: Venous leg ulceration(VLU) is one of the complications of lower extremity venous reflux and reflux disorder of severe diseases, with many adverse effects on patient's work and life. Nowadays, more and more patients with VLU accept wound care in community setting. Clinical nurses generally take care of the patients based on their own experiences. Healing in VLU is an incredibly complex process, which puzzles even experts. The majority of general nurses do not have this level of expertise, especially those nurses serving in community. Function is the basis of nursing activities. Patients always show different clinical manifestations and selfcare abilities due to various function states, which cannot be reflected completely by the existing nursing practice. How to describe nursing practice standardized in order to demonstrate the effectiveness of interventions and facilitate interdisciplinary communication is another urgent problem. Therefore, the aim of this project is to develop an accurate nursing program based on function in chronic venous leg ulcers, which can both satisfy the needs of patients and promote nursing revolution.Methods: This study will use International Classification of Functioning Disability and Health as a framework to choose suitable functions and to filter function classification standards of chronic venous leg ulcers through evidence-based systematic research.Nursing interventions related to VLU are selected based on Nursing Interventions Classification, adding other nursing activities by methods of evidence-based systematic review and clinical observation. Then, nursing interventions and function status are matched through steering committee. Finally, the Delphi survey method is adopted to make nursing program native and scientific.Conclusions: This study is expected to be very significant and meaningful in using standardized nursing terminology. The nursing program established could better meet the needs of both patients with chronic venous leg ulcers and clinical nurses, promot

关键词： accurate nursing program venous leg ulceration function status nursing intervention classification systematic review Delphi survey ICF LUMT

accurate extraction of fabricated geometry using optical measurement

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Photonics Research 2018年第11期6卷 1008-1020页

作者： YUFEI XING JIAXING DONG SARVAGYA DWIVEDI UMAR KHAN WIM BOGAERTS Photonics Research Group Ghent University-IMEC Center of Nano and Biophotonics Ghent Belgium Electrical and Computer Engineering Department University of California Santa Barbara Santa Barbara

We experimentally demonstrate extraction of silicon waveguide geometry with subnanometer accuracy using optical measurements. Effective and group indices of silicon-on-insulator(SOI) waveguides are extracted from the optical measurements. An accurate model linking the geometry of an SOI waveguide to its effective and group indices is used to extract the linewidths and thicknesses within respective errors of 0.37 and0.26 nm on a die fabricated by IMEC multiproject wafer services. A detailed analysis of the setting of the bounds for the effective and group indices is presented to get the right extraction with improved accuracy.

关键词： MZI accurate extraction measurement

accurate Electronic, Transport, and Related Properties of Wurtzite Beryllium Oxide (w-BeO)

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Journal of Modern Physics 2017年第12期8卷 1938-1949页

作者： Cheick Oumar Bamba Richard Inakpenu Yacouba I. Diakite Lashounda Franklin Yuriy Malozovsky Anthony D. Stewart Diola Bagayoko Department of Physics Southern University and A&M College Baton Rouge LA USA Department of Physics University of Sciences Techniques and Technologies of Bamako Bamako Mali

We report details of our ab-initio, self-consistent density functional theory (DFT) calculations of electronic and related properties of wurtzite beryllium oxide (w-BeO). Our calculations were performed using a local density approximation (LDA) potential and the linear combination of atomic orbitals (LCAO) formalism. Unlike previous DFT studies of BeO, the implementation of the Bagayoko, Zhao, and Williams (BZW) method, as enhanced by the work of Ekuma and Franklin (BZW-EF), ensures the full physical content of the results of our calculations, as per the derivation of DFT. We present our computed band gap, total and partial densities of states, and effective masses. Our direct band gap of 10.30 eV, reached by using the experimental lattice constants of a = 2.6979 Åand c = 4.3772 Åat room temperature, agrees very well the experimental values of 10.28 eV and 10.3 eV. The hybridization of O and Be p states in the upper valence bands, as per our calculated, partial densities of states, are in agreement with corresponding, experimental findings.

关键词： Density Functional Theory BZW-EF Method accurate Calculated Properties

accurate Symbolic Solution of Ginzburg-Landau Equations in the Circular Cell Approximation by Variational Method: Magnetization of Ideal Type II Superconductor

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Journal of Modern Physics 2017年第6期8卷 982-1011页

作者： O. A. Chevtchenko HTS-powercables.nl BV Apeldoorn The Netherlands

In this paper I access the degree of approximation of known symbolic approach to solving of Ginzburg-Landau (GL) equations using variational method and a concept of vortex lattice with circular unit cells, refine it in a clear and concise way, identify and eliminate the errors. Also, I will improve its accuracy by providing for the first time precise dependencies of the variational parameters;correct and calculate magnetisation, compare it with the one calculated numerically and conclude they agree within 98.5% or better for any value of the GL parameter k and at magnetic field , which is good basis for many engineering applications. As a result, a theoretical tool is developed using known symbolic solutions of GL equations with accuracy surpassing that of any other known symbolic solution and approaching that of numerical one.

关键词： Ginzburg-Landau Equations accurate Symbolic Solution Circular Unit Cell

Application of the “accurate Control Groundwater Resources” Theory in Containment of Groundwater Resource Exhaustion Trend

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Journal of Groundwater Science and Engineering 2013年第1期1卷 1-10页

作者： Jiansheng Shi Hongtao Liu Zhiyuan Liu Tieliu Chen Wenhong Zhao Yanming Sun Institute of Hydrogeology and Environmental Geology Department of Housing and Urban-Rural development of the Henan Province Shanxi Province Economic and Information Technology Committee Earthquake Administration of Chongqing Municipality Institute of World history CASS

The continued sustainable economic development of china depends in part,to the scientific management of China’s precious groundwater resources in the coming years.Groundwater resource scarcity is a common underlying problem across China,in addition,the large-scale groundwater exploitation for human consumption over recent decades has resulted in a series of environmental geological problems.As a result of these problems,the national economics in china have been seriously affected.In order to prevent groundwater resource exhaustion and environmental geology deterioration,“accurate control of groundwater resources(ACGR)”theory and its support system were established in this article,and the related prevention measures of the ACGR theory,such as accurate irrigation,accurate supply water,and accurate subsidies,were proposed.This paper highlights the ACGR theory as an efficient and essential way to achieve the sustainable groundwater resource management,which can be applied to countries such as China.

关键词： groundwater environmental geology accurate economic exploited ACGR WATER PROVINCE MODEL