• Journal of Mechanical Science and Technology
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• v.16 no.12
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• pp.1664-1672
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• 2002

Gantry mechanisms have been widely used for precision manufacturing and material handling in electronics, nuclear, and automotive industries. Dual-drive servo mechanism is a way to increase control bandwidth, in which two primary axes aligned in parallel are synchronously driven by identical servo motors. With this mechanism, a flexible coupling (compliance mechanism) is often introduced in order to avoid the damage by the servo mismatch between the primary drives located at each side of gantry. This paper describes the design guidelines of the dual-drive servo mechanism with focus on its dynamic characteristics and control ramifications. That is, the effect on the system bandwidth which is critical on the system performance, the errors and torques exerted on guide ways in case of servo mismatch, the vibration characteristics concerned with dynamic error and settling time, and the driving force required at each axis for control are thoroughly investigated.

• Journal of Korean Society for Quality Management
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• v.21 no.2
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• pp.71-84
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• 1993

Currently the problem of air pollution caused by the motor vehicle emission is one of the most serious problems to be solved. Thus we needed the vehicle emissions audit procedure and technical innovation constraining the motor vehicle emission. The Korean Environmental Protection Agency currently audits automobiles for emissions compliance at assembly plants with multiple attribute multiple staged sampling plans. In order to establish the more reasonable audit procedure, the multiple staged sampling plan designed in this paper has been applied to the domestic vehicles by analyzing the statistic characteristics of the emission distribution. This paper summarizes the auditing procedure and develops methods for determining its statistical characteristics. Specifically, we consider how to evaluate a multiple staged sampling plan, give a procedure that efficiently estimates attribute-type probabilities from multivariate variables-type data, and quantify the effect of tightening the acceptable quality level of the sampling plan. As a result it can be proved that this audit procedure is the reasonable plan minimizing the AQL (Acceptable Quality Level) and is to be used effectively for the auditing procedure constraining the injurious gasses of the motor vehicles.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.254-259
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• 2005

The heat and vibration effect is known to cause a serious deformation in linear motor system. The paper presents a heat and vibration characteristics that compare a advanced linear motor with developed linear motor through experiment and analyses. The heat in linear motor system is identified for experimental data and analytic data using the Finite Volume Method (FVM). Also, it shows that the optimum standard analyzed the acceleration patterns of the moving part cause the vibration source in linear motor. It presents the analyzed dynamics of linear motor in compliance with a deformation of the non-linear factor.

• Journal of the Korean Society of Safety
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• v.14 no.3
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• pp.18-24
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• 1999

This paper were performed to evaluate the elastic-plastic fracture toughness $J_IC$ by the unloading compliance method for 1/2 CT specimen of A5083-H112 aluminum alloy. A modified offset method for negative crack growth effect is presented and compared with Voss offset method. We found that the modified offset method presented can be used efficiently for a determination of the stable crack onset. The $J_IC$ by Voss offset method can be overestimated, but the suggested offset method showed a high reliability within 5% of tolerence from the results by the multi-specimen method.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.688-693
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• 2007

Most frame structures cannot be manufactured in a single-piece form. Ideally, when a structure is built up by assembling multi pieces, assembly at the joints should be rigidly performed enough to have almost full stiffness, which is difficult for practical reasons such as manufacturing cost and time. In this research, we aim to develop a manufacturability-oriented compliance-minimizing topology optimization using a ground beam model incorporating additional zero-length elastic joint elements. In the present formulation, design variables control the stiffness of zero-length elastic joints, not the stiffness of beams. Because joint stiffness values at the converged state can be utilized to select candidate assembly locations and their strengths, the technique is extremely useful to design multi-piece frame structures. An optimal layout is also extracted based on the stiffness values.

• 대한상한금궤의학회지
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• v.11 no.1
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• pp.83-94
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• 2019

Objective : There was an improvement in a patient with psoriasis following the intake of Hoeyeok-tang for 317 days. By analyzing these cases, we reviewed the use of Hoeyeok-tang in skin diseases and attempted to interpret the related Shanghanlun articles. Methods : The diagnostic process was analyzed according to the disease pattern identification diagnostic system based on the Shanghanlun provisions. The progression of psoriasis, which was addressed, was assessed using the PASI score. Results : The patient was diagnosed with Soeum-byung 324, and the PASI score decreased from 13.6 to 0.4 after the intake of Hoeyeok-tang for 317 days. The patient's compliance and expectation from treatment were good, and no specific adverse effect was identified. Conclusions : This study suggests the clinical use of Hoeyeok-tang in psoriasis based on Shanghanlun.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.269-272
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• 2006

The hydroforming processing is a relatively new technology in comparison with conventional stamping process. The hydroforming processing makes torsion beam in rear suspension of automobile. The durability of torsion beam is very important characteristic that operate in an automobile. In order to optimize the hydroforming process and satisfy the durability, the hydroforming simulation which could control an axial compression and high internal pressure with computer simulation has to be operated. This paper is about an optimum design to improve the kinematic and compliance characteristics of a torsion-beam of suspension system. The result from finite element analysis shows that the forming and the durability are optimized. If there is effect of First pressure in hydroforming processing that gap is in the die tool, the prototype of tube is not satisfied on the durability test.

• The Journal of the Korean dental association
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• v.41 no.10 s.413
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• pp.720-727
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• 2003

Clinicians generally agree that Class III malocclusion is one of the most difficult to treat. When the Class III malocclusion is characterized by maxillary retrusion in growing patients, the use of a face mask may be the treatment of choice. Although face mask can achieve excellent orthopedic effects. It demands special patient compliance because it is worn extraorally and is not as esthetic or comfortable as intraoral appliance. This report presents the clinical cases of mandibular protrusion correction in growing patients, who were treated by TTBA(Tandem Traction Bow Appliance) that's a intraoral appliance.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.385-390
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• 2000

In this study we propose the computational model for the coronary circulation. The bypass from left ventricle is also considered. Lumped parameter model with three compartments in the coronary circulation is implemented in this study. We connected the coronary artery compartment with left ventricle to explain the bypass procedure from left ventricle. The asymmetric resistance is assumed in the bypass line from left ventricle. The present numerical method is tested for normal coronary circulation and the results are compared with the existing computational work. The bypass simulation is conducted and the flow pattern is delineated. The effect of shunt resistance and coronary compliance to circulation is investigated for the better design of the bypass shunt.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1650-1655
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• 2010

This paper presents an activation plan for reliability centered maintenance (RCM) of rolling stock. The KTX is carrying out the maintenance in compliance with RCM. MKBSF, that is one of the reliability indices for KTX, is shown 183,483 km in 2009, whereas it is shown 68,986 km in 2004. It means that the reliability of KTX has been growing every year. It also is result of reliability management activities. KORAIL did not apply RCM until now about the conventional rolling stocks. But KORAIL decided that applies RCM system because of reliability management effect of KTX. In this study, we tried to know an activation plan for the reliability centered maintenance of the conventional rolling stocks.