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CONSTRUCTION OF RECTANGULAR DISPLACEMENT-BASED ELEMENT FOR THICK/THIN PLATES

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Acta Mechanica Sinica 1993年第2期9卷 163-170页

作者：卜小明龙驭球 dept.of Mechanics Tianjin UniversityTianjin 300072China dept.of Civil Engineering Tsinghua UniversitvBeijing 100084China

In this paper,a method of constructing displacement-based elment for thick/thin plates is devel- oped by using the technique of generalized compatibility,and a rectangular displacement-based element with 12 degrees of freedom for thick/thin plates is *** method enjoys a good accuracy with simple formulation and is free of shear- locking as the thickness of the plate approaches zero.

关键词： thick plate thin plate generalized compatibility finite element

Virtual test system for permanent-magnet DC motor

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Journal of Harbin Institute of Technology(New Series) 2003年第2期10卷 200-204页

作者：崔淑梅王悦柴凤吴红星刘宝廷程树康 dept.of Electric Engineering

In order to obtain the primary parameters and operating characteristics of a DC motor without directly measuring its torque and rational speed, it is proposed to use a PC and a data acquisition card to acquire both the dynamic and static data of armature current to establish the performance of a DC permanent magnet motor. The accuracy and validity of this virtual test system proposed were verified by comparing the measurements made with the system proposed with the measurements made with conventional torque meters. It is concluded from the results of comparison that from the mathematic model established for the DC permant magnet motors, both major parameters and operating characteristics can be directly established for the DC motors without measuring their torques and rotational speed, a perfect on line measurement and test system has been established for the DC permanent magnet motors using the theory of virtual test system. The system proposed features shorter test time, higher efficiency and lower cost.

关键词： virtual system motor test parameter identify

EXPERIMENTAL INVESTIGATION INTO PLASTIC DAMAGE OF MICROVOIDS WITH INTERACTION

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Acta Mechanica Sinica 1997年第3期13卷 280-288页

作者：方竞倪受庸杨宏伟白树林戴福隆 dept.of Mechanics & Engng.Science Peking UniversityBeijing 100871China dept.of Engng.Mechanics Tsinghua UniversityBeijing 100084China

A mechanism of plastic how localization in ductile matter near microvoids is studied. The voids with the size-scale of micromillimeter exist in sheet specimens under tensile loading, and the plastic strain held around voids is obtained by digital image processing of deformed grids. The size growth of the microvoids, the spacing change of the neighboring voids, and the development of shear bands in the ligament between the voids, are presented by experimental results accompanied with the plastic strain distribution, that gives good interpretation to the process of void growth and coalescence with the how localization in the ligaments.

关键词： void damage flow localization plastic strain field void interaction

Use of Unconventional Aggregates in Hot Mix Asphalt Concrete

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Journal of Civil Engineering and Architecture 2024年第1期18卷 30-37页

作者： Viktors Haritonovs dept.of Roads and Bridges Riga Technical UniversityRigaLatvia

The study investigates use of dolomite sand waste as filler or/and sand material plus BOF steel slag as fine and coarse aggregate for design of high performance asphalt *** environmental and economic factors contribute to the growing need for the use of these materials in asphalt concrete *** is particularly important for Latvia,where local crushed dolomite and sandstone does not fulfill the requirements for mineral aggregate in high and medium intensity asphalt pavements *** 100 to 200 thousand tons of steel slag aggregates are produced in ***,it has not been used extensively in asphalt pavement despite its high performance *** sand waste,which is byproduct of crushed dolomite production,is another widely available polydisperse by-product in *** quantity has reached a million of tons and is rapidly *** huge quantity of technological waste needs to be recycled with maximum *** combinations of steel slag,dolomite sand waste and conventional aggregates were used to develop AC 11 asphalt concrete *** mix properties tests include resistance to permanent deformations(wheel tracking test,dynamic creep test)and fatigue *** test results showed that asphalt concrete mixtures containing steel slag and local limestone in coarse portion and dolomite sand waste in sand and filler portions had high resistance to plastic deformations and good resistance to fatigue failure.

关键词： Steel slag dolomite sand waste permanent deformation creep test fatigue

A UNIFIED ENERGY APPROACH TO A CLASS OF MICROMECHANICS MODELS FOR COMPOSITE MATERIALS

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Acta Mechanica Sinica 1995年第1期11卷 59-75页

作者：黄永刚黄克智胡凯雄 A.Chandra dept.of Aerospace and Mech.Eng. The University of ArizonaTucsonAZ 85721USA dept.of Engineering Mechanics Tsinghua UniversityBeijing 100084China

Several micromechanics models for the determination of composite moduli are investigated in this paper,including the dilute solution,self-consistent method,generalized self-consistent method,and Mori-Tanaka's *** mi- cromechanical models have been developed by following quite different approaches and physical *** is shown that all the micromechanics models share a common ground,the generalized Budiansky's energy-equivalence *** dif- ference among the various models is shown to be the way in which the average strain of the inclusion phase is *** a bonus of this theoretical development,the asymmetry suffered in Mori-Tanaka's method can be circumvented and the applica- bility of the generalized self-consistent method can be extended to materials contain- ing microcracks,multiphase inclusions,non-spherical inclusions,or non-cylindrical *** relevance to the differential method,double-inclusion model,and Hashin-Shtrikman bounds is also *** application of these micromechanics models to particulate-reinforced composites and microcracked solids is reviewed and some new results are presented.

关键词： micromechanics models energy-equivalence framework dilute solution self-consistent method generalized self-consistent method Mori-Tanaka's method

Survivability analysis of wireless Ad hoc network using stochastic reward nets

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Journal of Harbin Institute of Technology(New Series) 2008年第4期15卷 535-539页

作者：赵靖崔刚刘宏伟王慧强 dept.of Computer Harbin Engineering University dept.of Computer Harbin Institute of Technology

To provide services in presence of failures or attacks in a timely manner, the network survivability was analyzed. Based on stochastic Petri nets, we put forward an effective model for ad hoe network and adopt a two-phase approach consisting of the steady-state availability analysis and the system transient performance analysis, then provide a quantitative approach for analysis of the network survivability. The results show that the proposed model is useful for the design and evaluation of the wireless ad hoc network.

关键词： survivability availability ad hoc network stochastic Petri nets

The Structural Engineering Challenges Following the Wenchuan Earthquake

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四川大学学报（工程科学版） 2009年第3期41卷 223-230页

作者： GRUNDY Paul dept.of Civil Eng. Monash Univ.

The "5·12" Wenchuan Earthquake presents two challenges-reconstruction of the devastated areas and building adequate seismic resistance into the rest of *** stages in recovery include structural condition assessment,identification of seismic weaknesses,appreciation of the variable seismicity of PR China,the development of a seismic performance index to aid the decision to relocate,rebuild or retrofit,development and application of the principles of retrofitting which recycles rubble and waste from Wenchuan "5·12",with an emphasis on integrating masonry construction into seismic *** recovery and resilience achieved through structural engineering must be integrated into a broader community involvement in disaster risk reduction.

关键词：建筑工程抗振结构建筑结构建筑物

DKLFRS:A Default Knowledge Logical Framework Representation System

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Journal of Computer Science & Technology 1992年第2期7卷 136-142页

作者：范仲春邢汉承 dept.of Maths.& Computer Nanjing Normal UniversityNanjing 210024 dept.of Computer Science Southeast UniversityNanjing 210018

The traditional reasoning system based on first order predicate logic can’t represent and handle de-fault *** paper presents a logical framework representation approach for default *** on Mixed SLDNF-resolution,a non... 详细信息

关键词： node DKLFRS

Performance-based seismic design of nonstructural building components:The next frontier of earthquake engineering

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Earthquake Engineering and Engineering Vibration 2014年第S1期13卷 17-46页

作者： Andre Filiatrault Timothy Sullivan dept.of Civil Structural and Environmental Engineering University at BuffaloState University of New York dept.of Civil Engineering & Architecture University of Pavia Assistant Professor

With the development and implementation of performance-based earthquake engineering,harmonization of performance levels between structural and nonstructural components becomes vital. Even if the structural components of a building achieve a continuous or immediate occupancy performance level after a seismic event,failure of architectural,mechanical or electrical components can lower the performance level of the entire building system. This reduction in performance caused by the vulnerability of nonstructural components has been observed during recent earthquakes worldwide. Moreover,nonstructural damage has limited the functionality of critical facilities,such as hospitals,following major seismic events. The investment in nonstructural components and building contents is far greater than that of structural components and framing. Therefore,it is not surprising that in many past earthquakes,losses from damage to nonstructural components have exceeded losses from structural damage. Furthermore,the failure of nonstructural components can become a safety hazard or can hamper the safe movement of occupants evacuating buildings,or of rescue workers entering buildings. In comparison to structural components and systems,there is relatively limited information on the seismic design of nonstructural components. Basic research work in this area has been sparse,and the available codes and guidelines are usually,for the most part,based on past experiences,engineering judgment and intuition,rather than on objective experimental and analytical results. Often,design engineers are forced to start almost from square one after each earthquake event: to observe what went wrong and to try to prevent repetitions. This is a consequence of the empirical nature of current seismic regulations and guidelines for nonstructural components. This review paper summarizes current knowledge on the seismic design and analysis of nonstructural building components,identifying major knowledge gaps that w

关键词： nonstructural building components performance-based earthquake engineering seismic design and analysis