• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.288-289
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• 2003

피부 표면 굴곡의 측정은 피부의 광노화의 정량화 , 피부관련 약품 및 기능성 화장품의 효과 평가, 피부 질환 진단 등에 반드시 필요하다. 기존에 사용되던 측정법으로는 스타일러스 (Stylus)법, 그림자(Shadowing)법, Laser Profilometry법 등이 있으나 이 방법들은 해상도 및 속도, 가격 등에 있어서 일반적으로 사용되기에는 부적합하다. 본 연구에서는 이 단점들을 극복하고 더 나은 굴곡 측정을 위해서 높은 횡·종축 해상도를 얻을 수 있는 저 결맞음 간섭계 (Low Coherence Interferometry, LCI)를 이용하여 피부 표면의 굴곡을 측정하였다.(중략)

• Journal of dental hygiene science
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• v.10 no.6
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• pp.445-450
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• 2010

The aim of this study was to evaluate the effect according to the fiber type and combination on the reinforcement of heat-polymerized denture base resin. The heat-polymerized resin(Vertex RS, Dentimax, Netherlands) was used in this study. Glass fiber(GL; ER 270FW, Hankuk Fiber Glass, Korea), polyaromatic polyamide fiber(PA; aramid; Kevlar-49, Dupont, U.S.A.) and ultra high molecular weight polyethylene fiber(PE, polyethylene; P.E, Dong Yang Rope, Korea) were used to reinforce the denture base resin specimens. The final size of test specimen was $64mm{\times}10mm{\times}3.3mm$. The specimens of each group were stored in distilled water at $37^{\circ}C$ for 50 hours before measurement. The flexural strength and flexural modulus were measured by an universal testing machine(Z020, Zwick, Germany) at a crosshead speed of 5 mm/min in a three-point bending mode. In this study, all fibers showed reinforcing effects on denture base resin(p<0.05). In terms of flexural strength and flexural modulus, glass fiber 5.3 vol.% showed most effective reinforcing effect on heat polymerized denture base resin. For flexural modulus, PA/GL was the highest in denture base resin specimen for hybrid FRC using two combination (p<0.05). Glass fiber 5.3 vol.% and PA/GL are considered to be applied effectively in reinforcing the heat polymerized denture base resin.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.243-248
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• 2009

Among 74 patients who came to pain clinic to treat their backache, 37 patient were randomly allocated to experimental(finger-pressure therapy)group and another 37 patients were allocated to control(transcutaneous electrical nerve stimulator)group. The extent of backache was compared before and after experiment by ANCOVA test at both groups(p<0.005). The reduction of pain level by visual analogue scale at experimental group was statistically significantly bigger than control group when motion with front flexion(1.92), extension after front flexion(2.22), right flexion(1.23), and left flexion(1.21)(p<0.05).

• Journal of the Korean Data and Information Science Society
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• v.20 no.2
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• pp.339-348
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• 2009

This study is to examine effects of motorized flexion-distraction treatment on the pain, lumbosacral angle, lumbar lordosis angle, and lumbar 5 (L5) intervertebral disc angle in patients with chronic low back pain. We selected 30 cases of chronic low back pain, which were evenly divided into two groups: experimental group and control group. We applied the same hot pack, interferential current therapy, and ultrasound therapy to both groups. The experimental group had additional treatment of motrized flexion-distraction therapy and control group had additional of stretching exercise. For each subject, the pain, lumbosacral angle, lumbar lordosis angle, and lumbar 5 (L5) intervertebral disc angle were measured before and after treatment, While experimental groups showed significant improvements after treatment, more significant effects were found in the experimental group.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.9
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• pp.1099-1103
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• 2011

Since the mechanical strength and stiffness of wire-woven bulk Kagome (BK) have been theoretically estimated by assuming that WBK is composed of straight struts, the analytical solutions occasionally give substantial errors as compared with the experimental results. The struts of WBK are helically formed, which results in errors in the estimations In this study, for accurately predicting the mechanical properties of WBK, the effects of waviness and brazed part are taken into account for estimating the strength and stiffness of WBK. The results are compared with the measured experimental results and the results estimated by a finite element analysis performed on a unit cell under periodic boundary conditions (PBC).

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.3
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• pp.177-185
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• 2014

In this study, the exoskeleton orthosis for the assistance of dorsiflexion torque in ankle joint to prevent foot-drop was developed. It was consist of three part; 1) the power part using artificial pneumatic actuator, 2) wearing part of ankle and knee joints to fix the orthosis, and 3) control part to detect the gait phase using physiological signal. The dorsiflexion torque was generated by the artificial pneumatic actuator connected with wearing part between ankle and knee joint. The accurate timing to assist dorsiflexion torque is made up of physiological signal in foot sole part that detect the gait phase, that is, stance and swing phase in each foot. We conduct the experiment to investigate the effect of exoskeleton orthosis to the 7 elderly people and 10 healthy people. The result showed that the muscular activities in tibialis anterior muscle were reduced because of the assistance of dorsiflexion torque in ankle joint using the exoskeleton orthosis.

• Korean Journal of Applied Biomechanics
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• v.19 no.2
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• pp.265-272
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• 2009

K. H. KIM, J. H. CHO, and S. C. LEE, The Effect of Taping on Lower Extremity during Jump Landing in Subjects with Functional Ankle Instability. Korean Journal of Sport Biomechanics, Vol. 19, No. 2, pp. 265-272, 2009. Ankle taping is thought that it can be very useful in clinical setting for reducing injury. However, the studies of ankle taping is focused only ankle joint. The purpose of this study was to examine the effect of taping on lower extremity during jump landing in subjects with functional ankle instability. we collected the data from VICON. Joint range of motion for sagittal plane, frontal plane and transverse plane were measured during a jump-landing task. Taping used in this study appeared to restrict ankle motion with altering the knee and hip joint ROM. We found ankle taping had effects of reducing PF, initial contact PF in sagittal plane, while increasing knee flexion, hip flexion, intial contact hip flexion statistically. It decreased ankle inversion, knee valgus, initial contact knee valgus, hip abduction in frontal plane and ankle abduction, hip internal rotation in transverse plane statistically. Ankle taping showed significant change Knee and hip joint ROM with ankle joint ROM.

• Composites Research
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• v.17 no.4
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• pp.7-17
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• 2004

In this study, the effect of laminate thickness on the compressive behaviour of composite materials is investigated through systematic experimental work using the stacking sequences, $[O_4]_{ns},{\;}[45/0/-45/90]_{ns}$ and $[45_n/0_n/-45_n/90_n]_s$ (n=2 to 8). Parameters such as fibre volume fraction, void content, fibre waviness and interlaminar stresses, influencing compressive strength with increasing laminate thickness are also studied experimentally and theoretically. Furthermore the stacking sequence effects on failure strength of multidirectional laminates are examined. For this purpose, two different scaling techniques are used; (1) ply-level technique $[45_n/0_n/-45_n/90_n]s$ and (2) sublaminate level technique $[45/0/-45/90]_{ns}$. An apparent thickness effect existes in the lay-up with blocked plies, i.e. unidirectional specimens ($[O_4]_{ns}) and ply-level scaled multidirectional specimens ($[45_n/0_n/-45_n/90_n]_s$). Fibre waviness and void content are found to be main parameters contributing to the thickness effect on the compressive failure strength. However, the compressive strength of the sublaminate level scaled specimens ($[45/0/-45/90]_{ns}$) is almost unaffected regardless of the specimen thickness (since ply thickness remains constant). From the investigation of the stacking sequence effect, the strength values obtained from the sublaminate level scaled specimens are slightly higher than those obtained from the ply level scaled specimens. The reason for this effect is explained by the fibre waviness, void content, free edge effect and stress redistribution in blocked $0^{\circ}$ plies and unblocked $0^{\circ}$ plies. The measured failure strengths are compared with the predicted values.

• Proceeding of EDISON Challenge
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• 2016.11a
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• pp.1-3
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• 2016

대형 화물 트럭(heavy-duty truck)은 화물 적재에 용이하지만, 공기역학적으로 불리한 형상을 가진다. 이러한 단점을 극복하고자 대형 화물 트럭에는 공기저항력(aerodynamic drag)을 줄일 수 있는 여러 가지 장치가 달려있다. 본 논문에서는 디플렉터(deflector) 형상이 항력 감소에 어떠한 영향을 주며, 평판 형태와 굴곡진 형태의 디플렉터 형상에 대한 항력 계수 비교를 EDISON-CFD를 활용하여 비교하였다. 해석 결과, 측풍(side-wind)의 영향을 무시하며 차량 속도 95 km/h로 등속을 유지하는 조건에서 평판 형태의 Model 1과 바깥으로 굴곡진 Model 2에서 전체 항력 계수가 낮게 나타났다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.82-82
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• 2017

현대농업에서 잡초를 조기에 제거하지 못할 경우 작물의 성장에 장애를 초래하므로 제초작업은 매우 중요하다. 최근 친환경 고품질 농산물에 대한 소비자의 관심과 고품질 농산물에 대한 가격 차별화 등으로 제초제를 사용하지 않은 친환경 재배가 주목을 받고 있다. 제초제는 농작물에 따라 분류가 되어있어 종류마다 효과가 다르고 사용방법이 종류에 따라 어떻게 사용되는지 알기가 쉽지 않아 이에 따른 피해 또한 무시 할 수 없다. 현재 상용화되어 있는 제초기는 굴곡이 있는 고랑의 잡초를 효율적으로 제거하기 어려워 밭작물 제초작업에 사용하기 부적합하다. 밭작물 재배 기간에 행해지는 고랑의 제초작업은 평지보다 더 많은 힘이 필요하고 일반적인 제초기로는 좋은 결과를 얻기 어렵다. 또한 제초 작업시 농작물 피해와 멀칭 비닐을 손상시키는 문제가 발생 하고 있다. 따라서 밭작물에 효율적인 잡초를 제거하기 위해 굴곡이 있는 지형의 잡초를 제거하기 위한 제초기 개발이 반드시 필요하다. 밭작물용 제초기를 개발하기 위해 굴곡이 있는 고랑의 잡초 제거가 가능한 제초날의 형상 설계가 우선되어야 하며, 고랑의 잡초제거를 위한 제초날 형상설계를 하기 위해 우리나라 주요 밭작물 재배지의 이랑 넓이, 고랑 깊이 및 고랑 폭을 조사 분석하였다. 조사 작물 대상은 양파, 마늘, 무, 배추, 고추, 당근, 감자 총 7가지 작물을 대상으로 조사하였으며, 각 작물들의 이랑 넓이와 고랑 깊이 및 폭의 평균치를 구하여 제초날 설계에 적용하고자 하였다. 범위가 있는 수치는 높은 수치를 기준으로 계산하였으며 고랑의 평균 폭은 34.2cm이고, 고랑의 평균 깊이는 22.1cm가 나타났다. 잡초를 효과적으로 제거하기 위해 제초날의 형상은 고랑의 크기 및 형태에 맞게 원형으로 설계를 하여야 한다. 형상 설계는 밭작물 고랑 평균직경 및 평균높이를 고려하고, 제초작업시 제초날이 작물 및 멀칭비닐의 손상 하지 않도록 하기 위해 직경은 고랑 평균 폭의 75% 정도 치수로 형상을 설계하고, 제초날 깊이는 고랑의 굴곡형태을 고려할 때 제초날 반경의 70%정도로 설계하여 원형제초날 폭 250mm, 제초날 깊이 87.5mm로 설계해야 할 것으로 분석 되었다.