• Computers and Concrete
• /
• v.8 no.3
• /
• pp.327-341
• /
• 2011

Three-dimensional graphic objects created by MATLAB are exported to the AUTOCAD program through the MATLAB handle functions. The imported SAT format files are used to produce the finite element mesh for MSC.PATRAN. Based on the Monte-Carlo random sample principle, the material heterogeneity of cement composites with randomly distributed fibers is described by the WEIBULL distribution function. In this paper, a concept called "soft region" including micro-defects, micro-voids, etc. is put forward for the simulation of crack propagation in fiber-reinforced cement composites. The performance of the numerical model is demonstrated by several examples involving crack initiation and growth in the composites under three-dimensional stress conditions: tensile loading; compressive loading and crack growth along a bimaterial interface.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.72-75
• /
• 2000

This paper presents a simulation study on the description of the motion and the control of an active catheter actuator with multi-link structure actuated by Shape Memory Alloy(SMA). The model of an active catheter adopted in this paper has 3 links, and the individual links are composed of 3 micro coils of SMA for the omni-directional motion. In order to analyze the motions of multi-link structure, 3-dimensional kinematics description is presented. Also, the motion control of the end point of an active catheter using simple Neural Network is shown based on GUI(Graphic User Interface) system.

• 제어로봇시스템학회:학술대회논문집
• /
• 1991.10a
• /
• pp.793-798
• /
• 1991

Implementation of AGVS (Automated Guided Vehicle System) in CIMS (Computer Integrated Manufacturing System) generally requires substantial study to optimize design and performance of the guide path. Traditional mathematical approaches have been used with limited success to analyze AGVS. These approaches, however, do not provide a practical opportunity to use by path designers. This paper presents a new approach based on Jules in designing and assessing AGV path to have better design of the closed-loop layout. A framework for the approach is proposed and a case study is reported to demonstrate the framework. Deletion of seldom used paths and addition of bypasses to solve the congestion problem are conducted automatically through simulation expefiments. To visualize die results a graphic control program is developed and integrated with AutoMod/AutoGram simulation package.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.698-700
• /
• 2003

This paper presents a model and analysis techniques for a unilateral external fixator to achieve fracture reduction and deformity correction in long bones precisely. through fixator joint adjustment. Combining the kinematic analysis with a graphic model of the tibia and the fixator allowed 3D simulation and visualization of the adjustments required to reduce fracture or correct bone deformity after osteotomy. The model and analysis technique can be used for fixator evaluation and clinical application planning.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1626-1629
• /
• 2003

The study is expressed on the web browser using virtual reality of developer manufacturing process and method or manufactured goods conviction for designer and developer with visualized model. This study purpose of basic feature with VRML file and Java and VRML with AWT to get WC code was presented. The study process is equal to the real thing modeling on using Pro/Engineer and exports on the VRML1.0. The condition converts VRML1.0 to VRML2.0 on the CROSS ROADS. And then Cosmo World is coding and manufacturing simulation is expressed on the Cosmo Player.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2003.05a
• /
• pp.110-114
• /
• 2003

In this study, a performance simulation program for a turbojet engine using SIMULINK, which can provide the GUI(Graphic User Interface) environment, was newly proposed. Performance analysis results using the SIMULINK performance program were compared with them using the FORTRAN performance program that was previously developed. According to comparison result, it was noted that performance analysis results between two programs have little bit big difference. This difference seems to be due to different component matching algorithm at each program, it will be improved later.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.49-54
• /
• 1992

A flexible robotic assembly cell is modeled using Petri net. A simulator is developed and used to predict the optimal status of the system. The assembly cell of flexible manufacturing system(FMS) pilot plant of Automation and Systems Research Institute(ASRI) in Seoul National University is modeled. The system consists of 3 robots, 4 conveyors, automatic guided vehicle(AGV) and auto-stacker. The simulator is programmed in Turbo C on IBM PC, supporting a simple graphic simulation with pull-down menu. The flexibility of the assembly cell in the FMS plant is guaranteed, since it is possible to predict the optimal status of the system using this simulator.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.332-336
• /
• 1992

We describe about the graphic simulation system which supports the determination of efficient multi-robot motions during cooperation. For the construction of the simulation software for multi-robot motions, two problems are presented. First problem is that all the robot motions must be determinded using both the desired object motions and the holonomic constraints with the object. To find the robot motions combined with the various object motion path, the robot motions are derived from the desired object path instead of a master robot path. Therefore robot motions can be easily modifiable with the various object motions. This type of motion determination is different from that of the master-slaves method using the master robot motions. The other is that the developments of robot application softwares need a heavy cost when the participated robots or the tasks given to the robots are changed. Based on object-oriented programming paradigm, we present useful software objects describing robot application programming environment. The object-oriented programming paradigm increases the software reusability, reliability, and extensibility, and also provides the structual concepts to cope with the various demands of robot application programming.

• 제어로봇시스템학회:학술대회논문집
• /
• 1987.10b
• /
• pp.269-272
• /
• 1987

This paper is concerned on kinematic analysis and simulation of an automatic feeding mechanism subjected by the motion of a curvilinear inverse cam. The main objection is the development of computer-aided design (CAD) program for simulating the motion of the cam-feeding mechanism using computer-graphics. A computer program CACAFS (Computer-Aided Cam and Automatic Feeding System) is independent of computer hardware used. The program is also interactive using a menu-selection technique. As the second part of the paper for the motion simulation of the cam-feeding system, this paper discusses the state-of-art for CAD. The first part of the paper presents the algorithm to simulate the notion of the cam-feeding mechanism.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.1
• /
• pp.151-161
• /
• 1997

In this paper we designed a high speed wireless multiple access protocol, which is suitable for future multimedia wireless LAN systems which support high quality video teleconferencing, telephony and graphic databases. In the proposed protocol, Slotted-ALOHA protocol is used for transmitting random data packets and the packet reservation multiple access(PRMA) protocol for transmitting periodic data packets. The use of minislot is introduced for the reservation scheme. In order to measure the performance characteristic of the proposed protocol, a simulator is designed using an object oriented programming language, C++, and an exhaustive simulation study is carried out. From the simulation results, it is observed that the proposed protocol and the existing PRMA protocol have almost the same delay characteristic when network traffic is low. However, the proposed protocol is superior to the PRMA protocol when traffic becomes higher. The proposed protocol and the results can be utilized for the design of the wireless access systems and future broadband wireless LANs.