• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.9 s.252
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• pp.1142-1147
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• 2006

A practical method for reducing the number of spot welds in automotive structures considering fatigue crack initiation life is suggested. At first, an influence index for the durability and the fatigue life of a spot weld itself is defined and then taken as the main effect of the DOE analysis. Spot welds that can be removed without serious reduction of durability through numerical experiments are selected by the results of DOE. The proposed method was applied to the shock tower and LCA(lower control arm) structure of a vehicle, which are important components in durability-related point of view.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.153-155
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• 2007

본 논문에서는 3상 저주파 변압기를 이용한 절연형 멀티레벨 인버터를 위한 새로운 공간 벡터 제어 방식을 제안한다. 제안된 제어 방식은 기존의 미리 계산된 표를 이용한 방식이 아닌 완전히 프로그래밍에 의한 방식으로 구현 시간은 기존 방식에 비해 늘이지 않으며, 확장성이 용의하다는 장점이 있다. 제안된 제어 방식을 공통암을 이용한 3상 IHCML 인버터에 적용하였으며, Matlab을 이용한 시뮬레이션 및 실험실 차원의 인버터 제작을 통하여 제안한 방식의 타당성을 검증 하였다.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2756-2758
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• 2003

ARM CORE용 칩으로 철도 종합 제어 부분에 이용될 수 있는 main processor 부분을 설계하고, JTAG 기술을 이용하여 그 안정성과 틸팅 기술에 이용될 수 있는 process를 사전 단계에서 bebugging 해보고, 이에 따른 신호 및 성능을 JTAG(Boundary Scan)을 이용하여 시스템의 신호와 파형을 시험 평가한다. 또한 예비 단계로의 JTAG 검증 가능성 여부를 알아보고자 한다. 철도 종합 제어 시스템의 신호 및 정확성을 측정해 보기 위한 선행 연구라 할 수 있다.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.7
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• pp.160-166
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• 1998

In this research a 2-dimensional motion generator composed of two linear motors was developed. The inertia, damping and/or stiffness characteristics of the motion generator can be changed on the real-time basis by properly regulating the force generated by the linear motors. That is, active impedance is implemented without actual change in the physical structure of the motion generator. Control of the motor force is carried out by controlling the input currents supplied to the linear motors based on the combination of the PI controller and feedforward controller. This motion generator can be used to measure a kinesthetic sense associated with the human arm and thus to develop the products for which the kinesthetic sense is taken into account.

• Bulletin of the Korean Chemical Society
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• v.13 no.4
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• pp.407-413
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• 1992

The chromatographic separation of the stereoisomers of the N-(3,5-dinitrobenzoyl) derivatives of fifteen dipeptide methyl esters and nine dipeptide alkyl esters was investigated on three different chiral stationary phases derived from N-acylated ${\alpha}-arylalkylamines$. Two of these CSPs contain second stereogenic centers. These secondary stereogenic centers of CSPs were proposed to provide secondary effects in terms of chiral recognition. From the elution orders of the four dipeptide stereoisomers and the separation factors of the enantiomeric pairs of the N-(3,5-dinitrobenzoyl) derivatives of the dipeptide alkyl esters having different alkoxy substituents, it was proposed that the intercalation of the alkoxy substituents of dipeptide derivatives between the connecting arm of CSPs may control the magnitude of chiral separations of dipeptide derivatives.

• PNF and Movement
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• v.15 no.1
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• pp.13-25
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• 2017

Purpose: This study investigated the coordination and contribution of body segments during functioning. Methods: The relevant literature related to body segments and function were reviewed. Results: Efficient control of function is considered with regard to a participant's ability to perform a sequence of movements in body segments, which progresses from the head to the arm, trunk, pelvis, and leg segments. Each segment performs a specific role, which environment explorer using visual information for the head, reaching and grasping for the arms, a stabilizer for the trunk, and the distribution of COM in the pelvis and leg. Conclusion: During any of the movements, the momentum generated by the proximal segments is transferred to the adjacent distal segments in an appropriate sequence. In assessing function for clinical intervention strategies, the segment coordination, segment sequence, transfer of the center of body mass, asymmetrical ratio, muscle activity, and compensatory strategies should be considered.

• IEMEK Journal of Embedded Systems and Applications
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• v.16 no.6
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• pp.247-251
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• 2021

We propose a protocol for Ethernet-based industrial real-time communication networks. In the protocol, the master periodically transmits control frames to all slaves, and the ring-type network topology is selected to achieve high-speed transmission speed. The proposed protocol is implemented in the form of both firmware and Linux kernel modules. To improve the transmission speed, the MAC address table is disabled in the firmware implementation, and the NAPI function of the Ethernet driver is removed in the Linux kernel module implementation. A network experiment environment is built with four ARM processor-based embedded systems and network operation experiments are performed for various frame sizes. From the experimental results, it is verified that the proposed protocol normally operates, and the firmware implementation shows better transmission speed than the Linux kernel module implementation.

• Physical Therapy Rehabilitation Science
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• v.10 no.3
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• pp.251-256
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• 2021

Objective: The forward head posture (FHP) is strongly related to the rounded shoulder posture (RSP), which is associated with shoulder pain. Design: Observational cross sectional study design Methods: A total of 37 were enrolled in the study, 22 individuals with FHP(experimental group) and 15 healthy adults(control group). Correlation with differences between groups was analysed through craniovertebral angle (CVA) representing FHP for both groups, neck disability index (NDI) indicating neck pain, disability of the arm, shoulder and hand (DASH) indicating shoulder pain. Results: There was a significant difference in the results of CVA, NDI, and DASH in FHP and healthy adults (p<0.05). Significant correlations were found between DASH and CVA in FHP participants (r = -0.656, p = 0.001). Also, in the regression analysis results of DASH and CVA, the regression model was found to be suitable and the variation in DASH could be explained by 43% (F = 15.118, p = 0.001). Conclusions: Shoulder pain and neck discomfort are potentially related, and an increase in shoulder pain can increase FHP.

• Proceedings of the KIPE Conference
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• 2018.11a
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• pp.163-164
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• 2018

본 논문에서는 새로운 MMC(Modular Multilevel Converter)용 SM(Sub-Module) 시험회로와 이를 제어하기 위한 제어기법을 제안한다. 계통연계형 MMC 시스템에서 한 상의 암(arm)에 흐르는 전류는 계통주파수의 2고조파 성분과 DC 전류를 포함하고 있다. 제안하는 시험회로는 암 전류를 선형적으로 근사화하고, 시험전류의 DC 성분을 제어하여 시험할 SM의 전압을 일정하게 유지한다. 시뮬레이션을 통해 제안하는 SM 시험회로와 제어의 타당성을 검증하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.1053-1054
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• 2009

무선 센서네트워크에서 지상시설물 관리를 위하여 대상 시설물에 대한 이벤트 발생 메시지 및 상황보고 메시지에 의한 데이터 수집 및 분석에 따르는 기존의 방식에 의해서는 시설물 상황 파악의 한계를 가지고 있다. 따라서 본 논문에서는 기존의 무선 센서네트워크에 적용되는 게이트웨이 기술에 영상 카메라를 이용한 영상제어 게이트웨이를 제안한다. 영상제어 게이트웨이를 적용함으로서 이벤트가 발생한 해당 센서노드에 대한 상황을 영상으로 인지하고 운용자 및 관리자의 시각적인 영상 정보 확인으로 관리대상 시설물의 상황 파악에 대한 정확도 및 신뢰도를 증대시킬 수 있다.