• IE interfaces
• /
• v.10 no.1
• /
• pp.155-167
• /
• 1997

The purpose of this study is to develop the program for efficient operation of a multi-functional surface mounting device(SMD) which mount various components on a printed circuit board(PCB). These components are provided by diverse types of feeders such as cassette, stick and tray feeders. The SMD has one or two heads. In the SMD, the positions of PCB and feeders and fixed, and the head moves to pick up a component from a feeder and to mount it on the PCB. The number of lanes occupied by each feeder and the nozzle used for each component can be different. We develop an off-line program to minimize the cycle-time of the SMD by studying the optimal assignment of feeders and the optimal mounting sequence of components. Graphical User Interface(GUI) is also developed. Additionally, we consider the line balancing problem which appears when two SMDs are used sequentially.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2011.07a
• /
• pp.80-81
• /
• 2011

컴포넌트 기반 프로그램은 동시에 여러 컴포넌트간의 상호 협력에 의해서 동작한다. 여러 개의 컴포넌트 기반 프로그램을 기존의 순차적 분석 방법을 이용하여 컴포넌트의 동작을 분석해야 하기 때문에 시간이 많이 소요되고 매우 불편하다. 더욱이 컴포넌트의 수가 많아지면서 각 단계마다 각각의 컴포넌트의 동작을 모두 추적한다는 것은 매우 어렵다. 본 논문에서는 컴포넌트 기반으로 설계된 프로그램의 동작을 나타내는 시퀀스 다이어그램을 자동으로 생성할 수 있는 방법을 제안한다. 컴포넌트 기반 프로그램의 UML 시퀀스 다이어그램을 자동으로 생성하여 시각적으로 보여주어 개발의 편의성과 효율성을 증가시킨다.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1995.04a
• /
• pp.306-315
• /
• 1995

This paper presents a bin picking method using a slit beam laser in which a robot recognizes all of the unoccluded objects from the top of jumbled objects, and picks them up one by one. Once those unoccluded objects are removed, newly developed unoccluded objects underneath are recognized and the same process is continued until the bin gets empty. To recognize unoccluded objects, a new algorithm to link edges on slices which are generated by the orthogonally mounted laser on the xy table is proposed. The edges on slices are partitioned and classified using convex and concave function with a distance parameter. The edge types on the neighborhood slices are compared, then the hamming distances among identical kinds of edges are extracted as the features of fuzzy membership function. The sugeno fuzzy integration about features is used to determine linked edges. Finally, the pick-up sequence based on MaxMin theory is determined to cause minimal disturbance to the pile. This proposed method may provide a solution to the automation of part handling in manufacturing environments such as in punch press operation or part assembly.

• Journal of the Korean Society for Railway
• /
• v.9 no.2 s.33
• /
• pp.206-211
• /
• 2006

This thesis presents railroad crew restoring problem, which is to determine the railroad plan allocation. This problem is constructed that determine the sequence of duties that railroad crews have to perform. We analyze characteristic of this problem and railroad industry. It's hard to consider many constraint conditions. We propose Integer Programming model and easy methodology to be considered all given operation rules. This problem is known to be NP-hard. We develop a genetic algorithm, which is proved to be powerful in solving optimization problems. We proposed the effective mathematical model and algorithm about making crew restoring in real industry.

• Transactions of Materials Processing
• /
• v.10 no.3
• /
• pp.246-246
• /
• 2001

The conventional and new forming processes of a steel shell body are analyzed by the rigid-plastic finite element method. The conventional process contains five forming stages such as bending, drawing, ironing, heading and sizing, which was designed by a forming equipment expert. The results of simulation of the conventional forming process are summarized in terms of deformation patterns and load-stroke relationships for each forming operation. Based on the simulation results of the current five-stage, the shell body forming Process including backward extrusion is designed for improving the conventional process sequence. Forming loads of the proposed process are within the limit value, which is proposed by experts and the proposed process is found to be proper for manufacturing steel shell body.

• Transactions of Materials Processing
• /
• v.10 no.3
• /
• pp.245-252
• /
• 2001

The conventional and new forming processes of a steel shell body are analyzed by the rigid-plastic finite element method. The conventional process contains five forming stages such as bending, drawing, ironing, heading and sizing, which was designed by a forming equipment expert. The results of simulation of the conventional forming process are summarized in terms of deformation patterns and load-stroke relationships for each forming operation. Based on the simulation results of the current five-stage, the shell body forming Process including backward extrusion is designed for improving the conventional process sequence. Forming loads of the proposed process are within the limit value, which is proposed by experts and the proposed process is found to be proper for manufacturing steel shell body.

• Journal of Institute of Control, Robotics and Systems
• /
• v.5 no.8
• /
• pp.907-913
• /
• 1999

For an automated transportation system like PRT(Personal Rapid Transit) system or IVHS, an efficient vehicle-merging algorithm is required for smooth operation of the network. For management of merging, collision avoidance between vehicles, ride comfort, and the effect on traffic should be considered. This paper proposes an unmanned vehicle-merging algorithm that consists of two procedures. First, a longitudinal control algorithm is designed to keep a safe headway between vehicles in a single lane. Secondly, 'vacant slot and ghost vehicle' concept is introduced and a decision algorithm is designed to determine the sequence of vehicles entering a converging section considering energy consumption, ride comfort, and total traffic flow. The sequencing algorithm is based on fuzzy rules and the membership functions are determined first by an intuitive method and then trained by a learning method using a neural network. The vehicle-merging algorithm is shown to be effective through simulations based on a PRT model.

• Korean Journal of Agricultural Science
• /
• v.37 no.1
• /
• pp.113-121
• /
• 2010

Land consolidation ratio for rice paddy fields reached to 64.7% as of 2008 in Korea, and this also accelerated automation of field machinery. Especially, research on autonomous tractors has been continuously conducted. Tillage is one of the labor-, energy-, and time-consuming field operations. Most important requirements for autonomous tractors would be travelling path planning and electronic system to control the tractor to follow the path. The instruction of computer was required to conduct the tillage operation in field with unmanned traveling tractor. This instruction was coincidently used in the control of the traveling path and the motion of tractor. The objectives of the study were 1) to characterize and model tillage operating sequence, turning pattern, and 2) to develop tillage path formation programs for autonomous tractor and evaluate the performance.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.167-168
• /
• 2009

The CFT structure is applied to newly developed CFTA girder because of improvement of ductility deformation, stiffness and internal force of structure owing to the interaction between steel tube and core concrete. CFTA girder is the structure which can reduce tensile stress due to external loads by using its arch shape and prestress force. This paper proposed constructional stage procedure and represented analytical technique considering constructional stage to investigate the safety against bridge collapse on construction and on operation.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.5C
• /
• pp.692-699
• /
• 2004

In this paper we studied an implementation of QR decomposition-based RLS algorithm using modified Givens rotation method. Givens rotation can be obtained with a sequence of the CORDIC operations. In order to reduce the computing time of QR decomposition we restricted the number of iterations of the CORDIC operation per a Givens rotation and used double-rotation method to remove the square-root in the scaling factor.