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design　AND　PREPARATION　OF　SILICON　NITRIDE　COMPOSITE　WITH　HIGH　FRACTURE　TOUGHNESS　AND　NACRE　STRUCTURE

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 479-484页

作者： Y Huang H.N Hao Y.L. Chen and B.L.Zhou (1)Department of Materials Science and Engineering, Tsinghua University,Beijing 100084, china 2)institute of Metal research, Chinese Academy of Sciences,shenyang 110015, china ) Tsinghua Univ Beijing China

A new way of designing and preparing silicon nitride ceramic composite with high fracture toughness and nacre structure has been proposed. To mimic the laminated structure of nacre, Si_3N_4 matrix ceramic layer can be obtained through compacting rolling method. To mimic the secondary toughening of nacre structure, SiC whisker is added into Si_3N_4 and acts as the secondary toughening phase. Boron nitride (BN)is selected to mimic the organic layer in nacre so as to form the weak interfaces between Si_3N_4 layers. Alumina is added into BN to adjust the bonding strength of the *** Si_3N_4 sheets are stacked into the die after coating with BN. After the removal of the organic matter in them, the green body is hot pressed at 1820℃for 1.5 hours under N_2 atmosphere. The fracture toughness of the so-made Si_3N_4 composite at room temperature is 20.36MPa m￣(1/2), the three-point bending strength at room temperature is 651.47MPa. The crack spreads and deflects along the interface between BN and Si_3N_4 layer and extends through the BN layer into Si_3N_4 layer. The improvement of the fracture toughness may be due to the staircase-shape-like crack which provides the long crack path, the fracture and deformation of Si_3N_4 layer, and the pullout of SiC whiskers from the Si_3N_4 layer.

关键词： secondary toughening,compact rolling silicon nitride nacre Structure

A model of 3D-structure of H+, K+-ATPase catalytic subunit derived by homology modeling

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Acta Pharmacologica Sinica 2004年第4期25卷 76-81页

作者： Dong YAN, Yuan-dong HU1, Song LI1, Mao-sheng CHENG2 shenyang Pharmaceutical University, shenyang 110016 1Academy of Military Medical Sciences, Beijing 100850, china shenyang Pharmaceutical University Shenyang 110016 Academy of Military Medical Sciences 北京 100850

AIM: To build a model of 3D-structure of H+, K+-ATPase catalytic subunit for theoretical study and anti-ulcer drug design. METHODS: The model was built on the basis of structural data from the Ca2+-ATPase. Structurally conserved regions were defined by amino acid sequence comparisons, optimum interconnecting loops were se- lected from the protein databank, and amino (N)- and carboxyl (C)-terminal ends were generated as random coil structures. Applying molecular mechanics method then minimized the model energy. Molecular dynamics tech- nique was used to do further structural optimization. RESULTS: The model of 3D-structure of H+, K+-ATPase was derived. The model is reasonable according to several validation criteria. There were ten transmembrane helices (TM1-TM10) in the model and inhibitor-binding site was identified on the TM5-8 riched negatively charged residues. CONCLUSION: The 3D-structure model from our study is informative to guide future molecular biology study about H+, K+-ATPase and drug design based on database searching.

关键词： peptic ulcer H(+)-K(+)-exchanging ATPase protein structural homology drug design

A Health Diagnosis Method for Aeroplane Structural Component Based on Fault Inference Engine

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A Health Diagnosis Method for Aeroplane Structural Component...

Development of a Wire Driven Robot for Grinding with Stiffness Adapted

2010 Chinese Control and Decision Conference

作者： Jianguo Cui~(1,2),Yingyu Wang~1,Zhonghai Li~1,Liqiu Liu~1,Guangyan Xu~1 1.Automatization College,shenyang institute of Aeronautical Engineering,shenyang 110136,china 2.shenyang Aeroplane design & research institute,shenyang 110035,china

As the health status of aeroplane structural components has direct impact on the flight,it is important to diagnose the health status of structural components *** this paper,acoustic emission technology is used to monitor the health status of the aeroplane structural *** acoustic emission health information from the aeroplane structural component is analyzed and *** fault inference engine that bases on rules and the forward chaining control strategies is *** K-means clustering analysis algorithm is used to diagnose the aeroplane structural component health *** show that the method has good performance to diagnoses the status for aeroplane structural *** presents a good health diagnosis method for aeroplane structural components,which can also be directly applied to other structural systems in machine equipments.

关键词： Forward Chaining Control Strategy Fault Inference Engine K-means Clusterin

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厦门大学学报（自然科学版） 2002年第S1期41卷 81-82页

作者： ZHANG Bo 1,2, ZHAO Ming-yang 2 (1. Graduate School of the Chinese Academy of Sciences, Beijing 100039 , china 2. Robotics Laboratory, shenyang institute of Automation, Chinese Academy of S ciences, shenyang 110016, china)

Along with development of new design and machining me thod production with more complex surface can be manufactured. researching on th e new equipment used for surface disposal has become the important matter. Grind ing and polishing are a common surface processing method. A new type wire driven parallel robot used for grinding processing is proposed in this paper. Wire driven parallel robot is developed from parallel robot and serial wire driven r obot. Steel wire is used to replace the leg of parallel robot. Compared with par allel robot, this kind of robot has lager workspace, lower weight, higher rigidi ty and higher load/deadweight ratio. And the stiffness of robot is controlled by changing the tension of wire. The robot proposed in this paper has three DOF. T he moving part is driven by four wires, three of them are used to drive and the rest to keep them tension, with a restraining machine. The position sensors are installed in restraining machine. The position of terminating of end-effecter c an be ascertained in the space. The tension sensors are installed in each wire t o form force feedback system. By changing the tension the force on the workpiece can be controlled. Also the stiffness of robot can be adjusted.

关键词： wire driven parallel robot stiffness control

Study of Nozzle and Vent Locations on Die Casting Filling Process

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厦门大学学报（自然科学版） 2002年第S1期41卷 29-30页

作者： GUI Gang, NIE Yi-yong (shenyang institute of Automation, Academia Sinica School of Graduate, Academia Sinica, shenyang 110016, china )

The casting nozzle location plays an important role in die casting. Improper location results in defects, such as cold shut, air cavity, shrinkage, etc. Therefore, it’s sure that the molten metal full fills the mould cavity before it solidifies. And, it’s to be wished that no vortex occur during the filling process, because the vortex is a main source that induces gas entrapment. To get the high quality and performance product, the inlet and outlet locations must be set properly. This paper, an optimal design problem of nozzle and vent locations, which is constrained by nonlinear partial differential equations and boundary and initial conditions, is introduced to describe the location selection on die casting filling process. By numerical simulation, one can compare the filling time, flow pattern and temperature field at different inlet and outlet locations, then choose the most proper locations.

关键词： casting nozzle location filling time optimal design temperature field

STUDY ON COMPOSITION design OF A SUPERALLOY

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Acta Metallurgica Sinica(English Letters) 1994年第3期7卷 187-193页

作者： WANG Zhixing, XIE Shishu, YANG Hongcai, LIU ShiguiNortheastern University, shenyang, china Northeastern Univ Shenyang China

A new superalloy without Co, Ta and Hf has been developed. The high temperature creep properties of the alloy approach to that of Mar-M246 superallov and with good antioxidation and anticorrosion abilities.

关键词： alloy design superalloy Mar-M246 alloy

REAL—TIME SIMULATION AND ADAPTIVE PID CONTROL OF QSK——O6A CONTROL FOR GAS TURBINE

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Chinese Journal of Aeronautics 1992年第1期 59-67页

作者： Zhang Shao-ji (shenyang Aeroengine research institute, P.O.Box 428, shenyang, 110015)

After hardware and software of a digital engine control system were developed, it isimportant for real-time simulation to be conducted on special test equipment to check thecorrectness of hardware and software design. A two-computer test device has been developedfor WJ-6G engine digital control system real—time simulation. It is flexible to modifythe real-time simulation for matching different system requirements. Rather than usesophisticated simulation bench, researchers have completed the WJ—6G engine digital controlsystem real-time simulation on the two—computer test device. From testing, a simpleengine model which combines the steady state model and linear transient model was developedand a simple adaptive PID algorithm which estimates the plant gain and updates thecontrol gain was verified. To solve the hardware and software problems by means of thereal-time simulation, the QSK-06A, a WJ-6G engine digital control system has been putinto operation.

关键词： PID O6A CONTROL FOR GAS TURBINE REAL TIME SIMULATION AND ADAPTIVE PID CONTROL OF QSK GAS

research on Airplane Health Forecast Method Based on the Improved MGM（1,n）

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Research on Airplane Health Forecast Method Based on the Imp...

Numerical Simulation of Transient Thermal Stress Field for Laser Metal Deposition Shaping

2009中国控制与决策会议

作者： Jianguo Cui~(1,2,3),Desheng Song~1,Shiliang Dong~3,Mingzhuo Wang~3,Xiaopeng Liang~3,Xinhe Xu~2 1.Automatization College,shenyang institute of Aeronautical Engineering,shenyang 110136,china 2.School of Information Science & Engineering,Northeastern University,shenyang 110004,china 3.shenyang aircraft design & research institute,shenyang 110035,china

＜正＞There is strong randomness and uncertainty lying in the health status of *** the former grey models can not forecast the random signals efficiently,a new forecast method for the health state of airplane,based on the improved MGM（1,n）,is presented in this *** advanced acoustic emission（AE） technique is used to collect the health state *** original AE signals are decomposed with the wavelet *** energy values, eigenvalues and standard deviation of the third layer wavelet decomposition low frequency coefficients are respectively extracted to form *** the improved MGM（1,n） is established by these *** improved algorithm is realized by feeding back the errors between the forecast values and the actual ones so as to improve the forecast *** show that the improved MGM（1,n） can forecast the airplane stabilizer fatigue crack more accurately than the GM（1,1）.And this new method has been successfully applied to the forecast system of the health state of airplane structure components.

关键词： Airplane Health Forecast Acoustic Emission MGM(1,n)

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武汉理工大学学报 2006年第S3期28卷 1025-1030页

作者： LONG Risheng~(1,2) LIU Weijun~1 (1.Advanced Manufacture Lab,shenyang institute of Automation,shenyang 110016,china 2.Graduate School,Chinese Academy or Sciences,Beijing 100039,china) Advanced Manufacture Lab Shenyang Institute of AutomationShenyang 110016China Graduate School Chinese Academy of SciencesBeijing 100039China Advanced Manufacture Lab Shenyang Institute of AutomationShenyang 110016China

To decrease thermal stress during laser metal deposition shaping(LMDS)process,it is of great importance to learn the transient thermal stress distribution *** on the“element life and death”technique of finite element analy- sis(FEA),a three-dimensional multi-track and multi-layer numerical simulation model for LMDS is developed with ANSYS parametric design language(APDL)for the first time,in which long-edge parallel reciprocating scanning paths is introduced. Through the model,detailed simulations of thermal stress during whole metal cladding process are conducted,the generation and distribution regularities of thermal stress are also discussed in *** the same process parameters,the simulation results show good agreement with the features of samples which fabricated by LMDS.

关键词： LMDS FEA transient thermal stress field numerical simulation