• The Journal of the Korea Contents Association
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• v.6 no.4
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• pp.46-54
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• 2006

We propose an optimization method for PCB assembly lines including multiple surface mounters. To increase the productivity of PCB assembly line, the component allocation, feeder assignment, and assembly sequence of each surface mounter should be optimized. The optimization Problem is formulated as an integer programming problem. We divide the overall problem into two hierarchical sub-problems: forward-path problem and backward-path problem. The clustering algorithm and branch-and-bound algorithm are applied to solve the forward-path problem. The assignment algorithm and connection algorithm are applied to solve the backward-path problem. Simulation results are presented to verify the usefulness of the proposed method.

• Journal of the Korea Society of Computer and Information
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• v.19 no.5
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• pp.89-98
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• 2014

This paper suggests heuristic algorithm for single-model simple assembly line balancing problem that is a kind of NP-hard problem. This problem primarily can be solved metaheuristic method. This heuristic algorithm set the main-path that has a most number of operations from start to end-product. Then the clustering algorithm can be assigns operations to each workstation within cycle time follow main-path. This algorithm decides minimum number of workstations and can be reduces the cycle time. This algorithm can be better performance then metaheuristic methods.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1846-1850
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• 2005

This paper presents a constrained-based routing (CBR) algorithm called, Dynamic Possible Path per Link (D-PPL) routing algorithm, for MultiProtocol Label Switching (MPLS) networks. In MPLS on-line routing, future traffics are unknown and network resource is limited. Therefore many routing algorithms such as Minimum Hop Algorithm (MHA), Widest Shortest Path (WSP), Dynamic Link Weight (DLW), Minimum Interference Routing Algorithm (MIRA), Profiled-Based Routing (PBR), Possible Path per Link (PPL) and Residual bandwidth integrated - Possible Path per Link (R-PPL) are proposed in order to improve network throughput and reduce rejection probability. MIRA is the first algorithm that introduces interference level avoidance between source-destination node pairs by integrating topology information or address of source-destination node pairs into the routing calculation. From its results, MIRA improves lower rejection probability performance. Nevertheless, MIRA suffer from its high routing complexity which could be considered as NP-Complete problem. In PBR, complexity of on-line routing is reduced comparing to those of MIRA, because link weights are off-line calculated by statistical profile of history traffics. However, because of dynamic of traffic nature, PBR maybe unsuitable for MPLS on-line routing. Also, both PPL and R-PPL routing algorithm we formerly proposed, are algorithms that achieve reduction of interference level among source-destination node pairs, rejection probability and routing complexity. Again, those previously proposed algorithms do not take into account the dynamic nature of traffic load. In fact, future traffics are unknown, but, amount of previous traffic over link can be measured. Therefore, this is the motivation of our proposed algorithm, the D-PPL. The D-PPL algorithm is improved based on the R-PPL routing algorithm by integrating traffic-per-link parameters. The parameters are periodically updated and are dynamically changed depended on current incoming traffic. The D-PPL tries to reserve residual bandwidth to service future request by avoid routing through those high traffic-per-link parameters. We have developed extensive MATLAB simulator to evaluate performance of the D-PPL. From simulation results, the D-PPL improves performance of MPLS on-line routing in terms of rejection probability and total throughput.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.31-34
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• 2000

In this paper, we design an optimal path for multiple mobile robots. For this purpose, we propose a new method of path planning for multiple mobile robots in dynamic environment. First, every mobile robot searches a global path using a distance transform algorithm. Then we put subgoals at crooked path points and optimize them. And finally to obtain an optimal on-line local path, ever)r mobile robot searches a new path with static and dynamic obstacle avoidance.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.1
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• pp.1187-1195
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• 2001

This paper presents a sweeping path planning algorithm for an autonomous smearing robot. An automatic planner generates a sweeping path pattern by proposed five basic procedures. This algorithm rocog-nizes obstacle on the architectural CAD draft and generates subgoals as tracking points which executes the area filling task based on heuristic approach. A sweeping path is planned by sequentially connecting the track-ing points in such a way that(1) the connected line segments should not be crossed, (2) the total tracking points should be as short as possible, and (3) the tracking line should not pass through the obstacle, Feasibility of the developed techniques has been demonstrated on a real architectural CAD draft.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1037-1040
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• 2002

In micro-stereolithography technology, fabrication conditions that include laser power, laser scan speed, laser scan pitch, and material property of photopolymer such as penetration depth and critical exposure are considered as major process variables. But the existing scan path generation methods based only on CAD model have not taken them into account, which has resulted in cross-section dimension of low accuracy. Thus, to enhance cross-section dimensional accuracy, the physical resin solidification n phenomena should be reflected in laser scan path generation and stage operating code. In this paper, multi-line experiments based on single line solidification model are performed. And the method for improving cross-section dimensional accuracy is presented, which is to apply the database based on experimental results to laser scan path generation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.5
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• pp.667-675
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• 2002

In this Paper, we present a new nonlinear active noise control scheme using neural networks. Two neural network4 are used, one is for the active controller and another one is for the secondary path model. This scheme is suitable for the plant which has time-varing secondary path dynamics, because the secondary path modeling is performed via on-line fashion. Simulation results of active noise control with nonlinear primary/secondary path are presented. The results show that the new algorithm can reduce the noise level greatly.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10a
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• pp.882-885
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• 1987

The path of an industrial manipulator in a crowded workspace generally consists of 8 set of Cartesian straight line path connecting a set of two adjacent points. To achieve the Cartesian straight line path is, however, a nontrivial task and an alternative approach is to place enough intermediate points along a desired path and linearly interpolate between these points in the joint space. A method is developed that determines the subtravelling- and the transition-time such that the total travelling time for this path is minimized subject to the maximum joint velocities and accelerations constraint. The method is based on the application of nonlinear programming technique, i.e., FTM (Flexible Tolerance Method). These results are simulated on a digital computer using a six-joint revolute manipulator to show their applications.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2986-2988
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• 2005

To improve the reliability of power-line communication systems, the measurement and analysis has been proceeded in many power-line channel environments. In spite of the wired channel, power line channel has many multi-paths that are changing with load-variation, line-interconnection, impedance mismatching and so on. We accordingly need an analysis method based on the multi-path channel impulse response. Recently, a method to describe the homogeneous Power-line network has been published[1]. In this paper the modified method that can describe both the homogeneous and non -homogeneous power-line network has presented.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.2
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• pp.12-21
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• 2013

This study developed searching network reduction algorithm for reduce shortest path searching time. Developed algorithm is searching nodes that have the including possibility of less weights path than temporal path that consists minimum number of nodes and minimum sum of the straight line distances. The node that has the including possibility of shortest path is the node that the sum of straight line distance from start node and straight line distance to target node is less than the value that temporary path's weights divided by minimum weights units. If searching network reconstitutes only these nodes, the time of shortest path searching will be reduced. This developed algorithm has much effectiveness that start node and target node is close in large network.