• Journal of Korean Society of Transportation
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• 제6권2호
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• pp.49-56
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• 1988

Alternate use of lane at a signalized intersection is a quite different control of the operation of an intersection. This control introduces a new stop line and signal before the original stop line. All of the lanes between the two stop lines are used for left turn traffic or through traffic at a time. The purpose of the control is increasing the capacity of a n intersection without widening the approach width. this paper contains a study on the condition of a application, the proper distances between the two stop lines, the reasonable offsets(rear) to guarantee clearing the vehicles of previous phase, the comparison of approach capacity between the existing control and this control. The study results reveals that the offsets(rear) are rather stable showing the range(maximum value minus minimum value) of it's value does not exceed 3.6 seconds according to the field data. The approach capacity will be increased by 27%, 43%, 59%, 84% when the distances between the stop lines are 30.0m respectively. The control might have theoretical limitation to operate in practice. So an experimental application of the control at some suitable intersections prior to expanding it.

• The Journal of Korea Robotics Society
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• 제2권4호
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• pp.289-296
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• 2007

The docking and recharging system for a mobile robot must guarantee the ability of the mobile robot to perform its tasks continuously without human intervention. In this paper, two docking mechanisms are proposed with localization error-compensation capability for the auto recharging system. Friction forces or magnetic forces are used between the docking parts of the docking module and those of the docking station. In addition, an auto recharging system is developed to control the power. Since the system is modularized, it can easily be adapted to other robots.

• Proceedings of the Korea Contents Association Conference
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• 한국콘텐츠학회 2003년도 춘계종합학술대회논문집
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• pp.361-367
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• 2003

Ad-hoc network is a multi-hop wireless network formed by a collection of mobile nodes without the aid of any establish infrastructure and this network can provide an extremely flexible method for establishing communications for fire, safety, rescue operations, battle field or other fields requiring rapidly deployable communications with survivable, efficient dynamic networking. Recently new expended mechanism is proposed as Ad-hoc relay system, so guarantee of QoS for multimedia applications is needed more and more. In this paper, we propose ARM based QoS Distribution Monitoring Mechanism to provide Quality of Service guarantees to multimedia application with MANET.

• Journal of Korean Neurosurgical Society
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• 제42권2호
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• pp.135-140
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• 2007

It is not the best way to treat a hopeless patient with life-sustaining medical devices until the heart beats stop. Advanced medical technology may prolong the life for a significant period without recovery from the disease. However, it would give an unbearable economic burden to the family and the society. In 2006, we decided not to operate 9 patients with traumatic intracranial hematomas. We examined those patients with special references to possible legal and ethical problems. It is reasonable to withhold a treatment after documentation that the family never wants any life sustaining treatment when the treatment does not guarantee the meaningful life.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제29권5C호
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• pp.595-600
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• 2004

In this paper, we propose a new simple scheme of layered nonlinear feedforward logic (NLFFL) overlaid on a linear feedback shift resistor (LFSR) to generate pseudonoise sequences, which have good balance property and large linear complexity. This method guarantee noiselike statistics without any designed connection scheme e.g. Langford arrangement.

• The Transactions of The Korean Institute of Electrical Engineers
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• 제64권2호
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• pp.289-296
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• 2015

In this paper, we propose the nonlinear control based on singular perturbation theory for position tracking and yaw regulation of planar motor. Singular perturbation theory is characterized by the existence of slow and fast transients in the system dynamics. The proposed method consists of auxiliary control to decouple error dynamics. We develop model reduction with control input. Also, we derIve decoupled error dynamics with auxiliary input. The controller is designed in order to guarantee the desired position and yaw regulation without current feedback or estimation. Simulation results validate the effect of proposed method.

• ETRI Journal
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• 제31권1호
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• pp.42-50
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• 2009

A new method for simulating voltage and current distributions in transmission lines is described. It gives the time domain solution of the terminal voltage and current as well as their line distributions. This is achieved by treating voltage and current distributions as distributed state variables (DSVs) and turning the transmission line equation into an ordinary differential equation. Thus the transmission line is treated like other lumped dynamic components, such as capacitors. Using backward differentiation formulae for time discretization, the DSV transmission line component is converted to a simple time domain companion model, from which its local truncation error can be derived. As the voltage and current distributions get more complicated with time, a new piecewise exponential with controllable accuracy is invented. A segmentation algorithm is also devised so that the line is dynamically bisected to guarantee that the total piecewise exponential error is a small fraction of the local truncation error. Using this approach, the user can see the line voltage and current at any point and time freely without explicitly segmenting the line before starting the simulation.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.404-411
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• 2010

The present paper deals with the continuous work of extending multi-dimensional limiting process (MLP), which has been quite successfully proposed on two- and three-dimensional structured grids, onto the unstructured grids. The basic idea of the present limiting strategy is to control the distribution of both cell-centered and cell-vertex physical properties to mimic a multi-dimensional nature of flow physics, which can be formulated as so called the MLP condition. The MLP condition can guarantee a high-order spatial accuracy without yielding spurious oscillations. Recently, MLP slope limiter was proposed based on the MUSCL-type reconstruction in two-dimensional case and it can be readily extended to three-dimensional case. Through various numerical analyses and extensive computations, it is observed that the proposed limiters are quite effective in controlling numerical oscillations and very accurate in capturing both discontinuous and continuous multi-dimensional flow features on 3-D tetrahedral grids.

• Journal of Korea Foundry Society
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• 제18권3호
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• pp.262-270
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• 1998

Gravity tilt pour casting can effectively guarantee the reduction of various casting defects by controlling the rotation speed and the tilting angle of the mold during tilt pouring. The relationship between casting process parameters and the soundness of castings has been investigated in order to determine the optimum process variables in the gravity tilt pour casting process. In order to evaluate the effect of rotation speed on mold filling patterns, a video camera was employed to visualize the in-situ fluid flow behavior of the molten metal, and the relevant fluid velocity was also estimated. X-ray and mechanical tests were also performed to evaluate the effect of fluid velocity on casting quality. With the rotation speed lower than 0.5 r.p.m., which is nearly corresponding to the critical velocity of stability in the fluid flow, sound castings were obtained without having any casting defects. It can be concluded that the gravity tilt pour casting process is an effective process for manufacturing sound casting products with enhanced physical and mechanical properties.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제25권3호
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• pp.443-451
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• 2001

This paper addresses an on-line scheduling method for track systems in semiconductor fabrication. A track system is a clustered equipment performing photolithography process in semiconductor fabrication. Trends toward high automation and flexibility in the track systems accelerate the necessity of the intelligent controller that can guarantee reliability and optimize productivity of the track systems. This paper proposes an-efficient on-line scheduling method that can avoid deadlock inherent to track systems and optimize the productivity. We employ two procedures for the on-line scheduling. First, we define potential deadlock set to apply deadlock avoidance policy efficiently. After introducing the potential deadlock set, we propose a deadlock avoidance policy using an on-line Gantt chart, which can generate optimal near-optimal schedule without deadlock. The proposed on-line scheduling method is shown to be efficient in handling deadlock inherent to the track systems through simulation.