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Effects of Vibration Technology and Polyvinyl Acetate Emulsion on Microstructure and Properties of Expanded Polystyrene Lightweight Concrete

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Transactions of Tianjin University 2009年第2期15卷 145-149页

作者：赵晓艳田稳苓姜忻良张雪松 School of Civil Engineering Tianjin University Civil Engineering institute Hebei University of Technology china academy of Building Research

To prevent expanded polystyrene （EPS） beads from rising up to the surface in the molding process of EPS lightweight concrete, vibration with pressure was applied and the polyvinyl acetate （PVA） emulsion was adopted to improve its mechanical properties. The mechanical properties, thermal properties and durability of EPS lightweight concrete were tested. The microstruetures of EPS lightweight concrete were observed by scanning electron microscope （SEM）. Vibration with pressure reduces the number of small cracks. The 180 d compressive strength and flexural strength increase obviously as a large amount of PVA was added. The mixed amount of PVA has no obvious influence on the thermal performance when it is not more than 10% of the cement. Vibration with pressure and surface modification of EPS beads by PVA improve the combination of EPS beads with cement stone and the mechanical properties of EPS lightweight concrete.

关键词： expanded polystyrene(EPS) lightweight concrete vibration with pressure polyvinyl acetate microstructure mechanical properties thermal properties

换位棋问题规则的表征与解题正确率间关系的研究

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心理科学 1997年第6期20卷 536-540页

作者：王东晖傅小兰中国科学院心理研究所

本研究通过对被试求解换位棋过程的记录与分析，重点研究了问题表征在换位棋求解过程中的作用。实验结果表明：（1）正确表征问题规则是解题的必要前提.对问题规则信息的误解和遗漏，是影响解题正确率的重要因素。其中对非隐含问题规则... 详细信息

本研究通过对被试求解换位棋过程的记录与分析，重点研究了问题表征在换位棋求解过程中的作用。实验结果表明：（1）正确表征问题规则是解题的必要前提.对问题规则信息的误解和遗漏，是影响解题正确率的重要因素。其中对非隐含问题规则的错误表征也占全部错误表征的很大比率。（2）“关键结构”的发现是解决换位棋的必要条件，对问题规则的错误表征影响“关键结构”的发现.（3）前置问题的解决经验对目标问题的正确表征无显著的影响作用。

关键词：问题规则问题表征关键结构换位棋心理学研究

ANALYTICAL MODEL OF HELICOPTER AIRCOMBAT AND MATHEMATICINVERSE SOLUTION

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chinese Journal of Aeronautics 1995年第4期8卷 237-246页

作者： Cao Yihua(institute of Fluid Mechanics, beijing University of Aeronauticsand Astronautics, beijing, china, 100083)

in helicopter air combat, the helicopter must have the maneuverability andagility to gain a firing position first and its weapon systems must be able to get firstround hits for successful air combat. In an attempt to address the questions, a generalanalytical model of helicopter / annament system combat is established. Taking the hel-icopter air combat at short range as an example, the kinematic law of a turreted gun iscalculated. The development and results here may provide a referable basis for maxinuz-ing the hit probability of the gun in air firing.

关键词： helicopters maneuvers flight combat

ASYMPTOTIC PROPERTY OF THE SOLUTION OF A FREELY ELASTIC BEAM WITH STRUCTURAL DAMPING

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science in china,Ser.A 1984年第12期27卷 1307-1316页

作者：宋健于景元胡顺菊肖永震朱广田 beijing institute of Information and Control Department of Mathematics Nankai University Tianjin Tianjin institute of systems science Aeademia Sinica beijing

In this paper the distribution parameter system of a freely elastic beam with struc-tural damping has been studied. Using the perturbation theory of linear operators in aHilbert space, we have proved that the solution of the equation exists and is unique. Someresults on the stability of such a kind of systems are also given. The results obtained hereconsist with the physical meaning of the problem.

关键词： Th ASYMPTOTIC PROPERTY OF THE SOLUTION OF A FREELY ELASTIC BEAM WITH STRUCTURAL DAMPING

Normal Form and Its Application to Non-Regular Linearization

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Normal Form and Its Application to Non-Regular Linearization

STATIONARY　BEHAVIOR　OF　THE　TWO－STAGE　TANDEM　QUEUEING　SYSTEM　WITH　FINITE　CAPACITY　AND　MATCHED　SERVICE

第二十二届中国控制会议

作者： Cheng Daizhan Hu Xiaoming Wang Yuzhen institute of systems science, chinese academy of sciences, beijing 100080 Dept. of Opt. and Sys. Theory, Royal institute of Technology, Stockholm, SWEDEN Dept. of Automation, Tsinghua University, beijing 100084

＜正＞This paper considers the problem of non-regular static state feedback linearization of affine nonlinear systems. First of all, we propose a now canonical form for nonregular feedback linear systems. Using this form, we obtain a special feedback normal form of nonlinear control systems. Based on such a normal form expression we investigate both explicit and approximate linearizations. Several easily verifiable conditions are provided. Finally, the semi-global linearization is also discussed.

关键词： Linearization Singular state feedback Normal form Semi-global

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systems science and Mathematical sciences 1994年第3期7卷 201-210页

作者： YUAN Xueming (institute of Automation, Acodemia Sinica, beijing 100080, china)

ＳＴＡＴＩＯＮＡＲＹＢＥＨＡＶＩＯＲＯＦＴＨＥＴＷＯ－ＳＴＡＧＥＴＡＮＤＥＭＱＵＥＵＥＩＮＧＳＹＳＴＥＭＷＩＴＨＦＩＮＩＴＥＣＡＰＡＣＩＴＹＡＮＤＭＡＴＣＨＥＤＳＥＲＶＩＣＥ￥ＹＵＡＮＸｕｅｍｉｎｇ（Ｉｎｓｔｉｔｕｔ... 详细信息

ＳＴＡＴＩＯＮＡＲＹＢＥＨＡＶＩＯＲＯＦＴＨＥＴＷＯ－ＳＴＡＧＥＴＡＮＤＥＭＱＵＥＵＥＩＮＧＳＹＳＴＥＭＷＩＴＨＦＩＮＩＴＥＣＡＰＡＣＩＴＹＡＮＤＭＡＴＣＨＥＤＳＥＲＶＩＣＥ￥ＹＵＡＮＸｕｅｍｉｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＡｕｔｏｍａｔｉｏｎ，Ａｃｏ...

关键词： State process stationary probability vertor positive recurrent distribution of stationary queue length.

Study on Coal Mild Gasification with Calcium Oxide in Fluidized Bed

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Study on Coal Mild Gasification with Calcium Oxide in Fluidi...

Establishment of Statistical Model for Precipitation Prediction in the Flood Season in china

Third Joint china/USA Chemical Engineering Conference

作者： Zhu Tingyu Xiao Yunhan institute of Engineering Themvophysics, chinese academy of sciences, P.O.BOX 2706, beijing, 100080, P.R.china

Pyrolysis of Shenmu bituminous coal in both presence and absence of calcium oxide was studied under atmospheric pressure and temperature range of 45050℃ in a fluidized bed reactor. The calcium oxide significantly increases the gas yield while decreases the tar yield. Tars in both the presence and absence of calcium oxide were analyzed and compared. The results indicated that tar yields reach the maximum at 650℃ for coal without calcium oxide. But when calcium oxide is added, the temperature of tar maximum yield is reduced to 550℃. It is also demonstrated that BTX and PCX in tar increase in the presence of calcium oxide. The proximate and ultimate analyses of chars are also conducted.

关键词： calcium oxide coal mild gasification fluidized bed

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Meteorological and Environmental Research 2011年第3期2卷 1-3页

作者： CHENG Zhi1,2 1.College of Atmospheric sciences,Lanzhou University,Lanzhou 730000,china 2.Key Laboratory for Climate-Environment in East Asian Region,institute of Atmospheric Physics,chinese academy of sciences,beijing 100029,china

[Objective] The research aimed to establish the regression model which was used to predict the precipitation in the flood season in china.[Method] Based on statistical model,North Atlantic oscillation index and the sea surface temperature index in development and declining stages of ENSO were used to predict East Asian summer monsoon *** the stations were divided into 16 zones,the same factors were used to establish the regression model predicting the station precipitation in the flood season in ***,it was compared with the model that predicted firstly the monsoon index and estimated the precipitation.[Result] The prediction results of summer precipitation during 2005-2009 by every model were *** was found that the model that the factor predicted indirectly the regional precipitation was better than that predicted indirectly the station ***,the model that the factor predicted directly the regional precipitation was better than that predicted indirectly the regional *** prediction score P of optimum model that three factors predicted directly the regional precipitation reached averagely 74.2,and the anomaly correlation coefficient ACC was averagely *** from the comparison situation of positive and negative zone distribution of precipitation anomaly percentage between the predicted and observed values in 5 years,the prediction effects in the south and east of Northeast china,some areas in the south of Yangtze River,the coast of South china and most areas of Xinjiang were *** predicted positive/negative distribution of precipitation anomaly percentage tallied with that of observation.[Conclusion] The model could predict well summer precipitation in china.

关键词： East Asian monsoon index Linear regression Summer precipitation ENSO North Atlantic oscillation index china

Preliminary Study on the Mechanisms of Solids Segregation in Debris Flows

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Preliminary Study on the Mechanisms of Solids Segregation in...