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Performance-based methodology for assessing seismic vulnerability and capacity of buildings

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Earthquake engineering and engineering Vibration 2010年第2期9卷 157-165页

作者： Lin Shibin1. Xie Lili1. 2,Gong Maosheng1.2 and Li Ming1.3 1.Institute of engineering Mechanics,China Earthquake Administration, Harbin 1.0080, China 2.{1. of Civil engineering,Harbin Institute of Technology,Harbin 1.0090, China 3.{1. of Civil engineering,shenyang Jianzhu university,shenyang 1.01., China Institute of engineering Mechanics China Earthquake Administration Harbin 150080 China

This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed.

关键词： performance-based vulnerability building damage seismic capacity software HAZUS

Influence of Controlled Rolling and Cooling Process on the Mechanical Properties of Low Carbon Cold Forging Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 595-599页

作者： LI Zhuang 1.WU Di 2,ZHENG Hui 1.DONG Xue-xin 2 (1.school of Materials Science and {1.,shenyang university of Aeronautics and Astronautics,shenyang 1.01.6,Liaoning,China 2.State Key Laboratory of Rolling and Automation,Northeastern university,shenyang 1.0004,Liaoning,China) shenyang Univ Aeronaut & Astronaut Sch Mat Sci & Engn Shenyang 110136 Liaoning Peoples R China Northeastern Univ State Key Lab Rolling & Automat Shenyang 110004 Liaoning Peoples R China

In the present paper,controlled rolling and cooling processing was conducted by using a laboratory hot rolling *** influence of different processing parameters on the mechanical properties of low carbon cold forging steel was *** results show that the faster cooling after the deformation (especially in low temperature rolling conditions) leads to the refinement of the ferrite *** specimen exhibits very good mechanical properties owing to the finer ferrite *** pearlite morphologies can also affect the mechanical properties of low carbon cold forging *** mechanical properties increase with decreasing final cooling temperature within the range from 650℃ to 570 ℃ due to the finer interlamellar spacing of pearlite *** mechanical properties of the specimens with fast cooling after the conventional rolling are not only better than those of the specimens with slow cooling after low temperature rolling,but also almost similar to those of the specimens with fast cooling after low temperature *** is suggested that fast cooling after high temperature rolling (the conventional rolling) process would be of important industrial value.

关键词： controlled rolling and cooling process low carbon cold forging steel fast cooling the finer ferrite grains mechanical properties

H∞ control for uncertain Markovian jump systems with mode-dependent mixed delays

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Progress in Natural Science:Materials International 2008年第3期18卷 309-314页

作者： Yingchun Wang, Huaguang Zhang school of {1. Science and engineering, Northeastern university, shenyang 1.0004, China school of {1. Science and engineering Northeastern University Shenyang 110004 China

We study the problem of H∞control for a class of Markovian jump systems with norm-bounded parameter uncertainties and mode- dependent mixed delays including discrete delays and distributed delays in this paper. Our aim is to present a new delay-dependent con- trol approach such that the resulting closed-loop system is robust mean-square (MS) exponentially stable and satisfies a prescribed H∞performance level, irrespective of the parameter uncertainties. Such delay-dependent approach does not require system transformation or free-weighting matrix. A numerical example shows that the results are less conservative and more effective.

关键词： H1.control Markovian jump Mixed delays Delay-dependent criterion

An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

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Progress in Natural Science:Materials International 2007年第10期17卷 1235-1240页

作者： Fan Hongjuan1. Feng Jiuchao1.2, Xie Shengli2 and Wang Shiyuan1.1. Faculty of Electronic and information {1. ,Southwest university, Chongqing 40071., China 2. school of Electronic and information {1., South China university of Technology, Guangzhou 51.641. China) Faculty of Electronic and information {1. Southwest University Chongqing 400715 China school of Electronic and {1. engineering South China University of Technology Guangzhou 510641 China

A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.

关键词： chaos unscented Kalman filter Lyapunov exponents aperiodicity.

Optimum Design of Movable Screen Jig Cycle

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 246-249页

作者： Chunbao Sun Yubo Sun(1.Resources engineering {1., university of Science and Technology Beijing, Beijing 1.0083. China2 Department of Mineral engineering, Northeastern university. shenyang 1.006. China) Resources engineering {1. University of Science and Technology Beijing Beijing 100083 China Department of Mineral engineering Northeastern University Shenyang 110006 China

The basic method for designing and calculating reasonable jig cycle of movable screen jig was presented. The reasonabilityand reliability of designed jig cycle were verified by' means of the test on artificial mixed materials. An iron ore (1.-1.0 mm) was treatedin tile TJD-75 model movable screen jig with the jig cycle. The good results were achieved. This would provide a reliable basis for designof commercial movable-screen jig.

关键词： movable-screen jig jig cycle optimum design

Performance analysis of network coding for multicast relay system over Nakagami-m fading channels

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Science China(information Sciences) 2011年第11期54卷 2338-2348页

作者： ZHAO Rui 1.YANG LvXi 2 & HUANG YongMing 2 1.school of {1. Science and engineering,Huaqiao university,Xiamen 361.21.China 2 school of {1. Science and engineering,Southeast university,Nanjing 21.096,China 1. school of {1. Science and engineering Huaqiao University Xiamen 361021 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China

The outage probability performance of network coding for multicast relay system is analyzed in Nakagami-m fading *** transmission strategies,i.e.,complex field network coding (CFNC) and amplify-and-forward network coding (AFNC),are applied in the system,and the approximate expressions of outage probability are derived at high SNR and the conclusion is reached that the system diversity gains of two transmission strategies are both 2m,as is verified by numerical *** results also show that CFNC can outperform both AFNC and direct transmission without relay in the performances of system outage probability,sum rate and symbol error ratio.

关键词： multicast relay system network coding outage probability diversity gain

Microwave Disinfection in a Ventilation and Air-Conditioning System

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湖南大学学报（自然科学版） 2009年第S1期36卷 55-59页

作者： LU Zhen1.2,ZHANG Ji-li1.MA Liang-dong1.HE Juan3(1.school of Civil & Hydraulic {1.,Dalian university of Technology,Dalian,Liaoning 1.6023,China 2.Municipal and Environmental {1. Research Center,shenyang Jianzhu university,shenyang,Liaoning 1.01.8,China 3.school of Municipal & Environmental {1.,Harbin Institute of Technology,Harbin,Heilongjiang 1.0090,China) school of Civil and Hydraulic {1. Dalian University of Technology Dalian 116023 China Municipal and Environmental engineering Research Center Shenyang Jianzhu University Shenyang 110168 China school of Municipal and Environmental {1. Harbin Institute of Technology Harbin 150090 China

Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC *** microwave disinfection devices were developed combined with air filter,the design and calculation method was presented,and the disinfection effects on White staphylococcus,Staphylococcus aureus,Bacillus Subtilis,Escherichi coli were *** results show that the major influence factors on disinfection effect are microwave power,water-content of filter material,disinfecting *** 1. min,the kill ratio is >90%,and the log value is >*** microwave field is uniform and the kill effect of bacteria on each surface of filter is the same,without statistically significant difference.

关键词： VAC system microwave disinfection airborne microbe microwave power kill ratio

STEP-NC Based High-level Machining Simulations Integrated with CAD/CAPP/CAM

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International Journal of Automation and computing 2012年第5期9卷 506-517页

作者： Yu Zhang 1.Xiao-Lan Bai 1.Xun Xu 2 Yong-Xian Liu 1.1.school of Mechanical {1. & Automation,Northeastern university,shenyang 1.0004,China 2 school of {1.,university of Auckland,Auckland 1.1.,New Zealand 1. school of Mechanical {1. & Automation Northeastern University Shenyang 110004 China 2. school of {1. University of Auckland Auckland 1010 New Zealand

With the development of manufacturing,numerical control(NC) machining simulation has become a modern tool to obtain safe and reliable machining *** some research and commercial software about NC machining simulations is available,most of them is oriented for G&M *** is a low-level data model for computer numerical control(CNC),which has inherent drawbacks such as incomplete data and lack of *** limitations hinder the development of a real simulation ***,standard for the exchange of product data-compliant numerical control(STEP-NC) is a new and high-level data model for *** provides rich information for CNC machine tools,which creates the condition for an informative and real ***,this paper proposes STEP-NC based high-level NC machining simulations solution integrated with computer-aided design/computeraided process planning/computer-aided manufacturing(CAD/CAPP/CAM).It turned out that the research provides a better informed simulation environment and promotes the development of modern manufacturing.

关键词： Standard for the exchange of product data-compliant numerical control(STEP-NC) numerical control(NC) machining machining simulation IDEF0 method ISO 6983

Experiment and Numerical Simulation on Axial Compressive Performance of Autoclaved Fly Ash Solid Brick Masonry Columns

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Transactions of Tianjin university 2011年第6期17卷 454-460页

作者：徐春一刘明周海鹰 Faculty of Infrastructure engineering Dalian University of Technology school of Civil {1. Shenyang Jianzhu University

To study the influence of slenderness on the axial compressive performance of autoclaved fly ash solid brick masonry columns, compression experiments were conducted on 1. samples of autoclaved fly ash solid brick masonry column and 4 samples of fired clay brick masonry column. The damage patterns and compressive performance were compared and analyzed. The experimental results indicate that the compressive bearing capacity decreases as slenderness increases from 3 to 1., and the compressive bearing capacity of the autoclaved fly ash solid brick masonry columns is lower than that of the fired clay brick masonry columns. The formulae for the axial compressive bearing capacity of autoclaved fly ash solid brick masonry columns were derived based on the experiments. The nonlinear FEA program ANSYS was adopted to simulate the behaviors of masonry columns. By comparing the simulation results and experimental results, it is shown that the simulation results agree well with the experimental ones. The rationality and applicability of the simulation results were verified.

关键词： masonry autoclaved fly ash solid brick compressive bearing capacity slenderness numerical simulation