• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1907-1909
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• 1996

In this paper, ultrsonic detection properties at a premolde joint utilized in a 23kV cables are studied. In a experiment a artificial defect within a joint and a measuring system are builded for generating discharges, gathering data about a detection properties, respectively. The experiment results show that one point detection is not allowed for monitoring a global status of a joint discharges and a detection sensitivity is less than 100pC. And also the attenuation and wave speed at the material of joint insulator are obtained.

• 자원환경지질
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• 제33권4호
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• pp.309-320
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• 2000

Aperture is an important parameter for determining the hydraulic characteristics of fractured media. In this study the topography of artificial rock joint surface was measured using 3D laser profilometer to analyze the aperture distribution. The initial aperture distribution was determined when the contact area became one percent of total joint surface. The initial aperture distribution of granite joint, with the mean value of 0.78 mm and the standard deviation of 0.34 mm was much different from that of the marble joint, with the mean value of 0.57 mm and the standard deviation of 0.26 mm. Apertures of both granite and marble showed normal distributions. Aperture distribution with the contact area of 25% was also analyzed. Mean value was decreased to one third compared to the initial aperture, but the standard deviation was decreased slightly. To determine the spatial correlation of the aperture distribution variogram analysis was carried out on the initial aperture data. Most experimental variograms were fitted well with exponential model. It is expected that the measured aperture characteristics can be used for stochastic analysis of fluid flow through rock joints.

• KIEE International Transactions on Electrophysics and Applications
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• 제2C권5호
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• pp.239-245
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• 2002

In this work, in order to realize the possible defects at the cable joint interface, four different types of artificial defects are provided : conducting, insulating substances, void and scratches. The analysis related to the PD patterns has been performed by means of conventional Phase Resolved Partial Discharge Analysis (PRPDA) and Chaotic Analysis of Partial Discharge (CAPD) as well which was proposed by our previous communication. As a result, it could be pointed out that each defect has shown particular characteristics in its pattern respectively and that the nature of defect causing partial discharge could be identified more distinctively when the CAPD is combined with the conventional statistic method, PRPDA.

• 제어로봇시스템학회논문지
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• 제16권10호
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• pp.919-926
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• 2010

This paper proposes a wearable hand rehabilitation device, DULEX, for persons with functional paralysis of upper-limbs after stoke. DULEX has three degrees of freedom for rehabilitation exercises for wrist and fingers except the thumb. The main function of DULEX is to extend the range of motions of finger and wrist being contracture. DULEX is designed by using a parallel mechanism, and its parameters such as length and location of links are determined by kinematic analysis. The motion trajectory of the designed DULEX is aligned to human hand to prevent a slip. To reduce total weight of DULEX, artificial air muscles are used for actuating each joint motion. In feedback control, each joint angle is indirectly estimated from the relations of the input air pressure and the output muscle length. Experimental results show that DULEX is feasible in hand rehabilitation for stroke survivals.

• 한국공작기계학회논문집
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• 제17권3호
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• pp.108-114
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• 2008

Uniaxial tension and compression test were conducted on conventional and crosslinked ultra-high molecular polyethylene (UHMWPE) all prepared from the same lot of medical grade GUR 1050. The conventional materials were unirradiated and gamma irradiated with $25kGy{\sim}200kGy$. Gamma irradiated processing was found to significantly impact the crystallinity, and hence the mechanical behavior, of the highly crosslinked UHMWPE. The crystallinity and radiation dose were key predictors of the uniaxial yielding, hardness, plastic flow, and failure properties of conventional and highly crosslinked UHMWPE. The correlation model from experiments would be the basic information to design the liner of artificial joint.

• 대한의용생체공학회:의공학회지
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• 제21권2호
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• pp.201-212
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• 2000

본 논문에서는 인공고관절과 환자의 고관절 부위를 각각 3차원 영상화한 후에 이들의 정합도 (fitness)를 측정하여 수치적인 정보로 제공함으로써 환자의 체형에 적합한 인공고관절을 선택하고, 더 나아가 정확한 시술방향과 시술깊이를 제공할 수 있는 모의시술시스템을 제시하였다. 이를 위해 region growing 기법등을 이용하여 환자의 CT 영상을 3차원화하고, 또한 인공고관절을 projection 기법 등을 통해 3차원 영상화하였으며, 지금까지 인공고관절 정합도 측정에 사용했던 단순한 단면적 비교방식과는 달리 삽입의 균일성도 가늠할 수 있는 새로운 정합도 측정 방식을 고안하여 적용하였다. 다양한 실험과 분석을 통하여 새로 제안한 정합도 측정 방법의 정확성과 우수함을 확인할 수 있었으며, 본 논문에서 제시하는 모의 시술시스템은 향후 정형외과 분야에서 인공무릎과 같은 다른 영역에서의 시술 보조 시스템으로도 응용될 수 있을 뿐만 아니라, 인공관절의 국산화 및 주문제작 등에성도 많은 활용을 할 수 있을 것으로 기대된다.

• 대한기계학회논문집A
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• 제37권12호
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• pp.1521-1527
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• 2013

본 논문에서는 마스터 조정자인 인간의 근육강도과 관절변위를 측정하여 슬레이브장치가 외부환경에 맞는 작업능력을 발휘할 수 있는 마스터/슬레이브 원격조정시스템을 제안한다. 외골격형 기구부와 경량의 관성센서를 사용하여 마스터 착용자의 편리성을 높였으며 인간의 근육과 동일한 운동특성을 가진 공압인공근육으로 슬레이브 기구장치를 구성하여 운동의 모사능력을 향상시켰다. 실험을 통해서 단순히 마스터의 위치정보만 전달하는 원격조정에 비해서 제안된 마스터는 인간 조정자가 근력의 세기를 조절함으로써 슬레이브에 작용하는 가반하중의 변화에 관계없이 균일한 제어성능을 가질 수 있었다.

• 근관절건강학회지
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• 제29권1호
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• pp.50-59
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• 2022

Purpose: This qualitative study aimed to explore the experiences of patients with diabetes provided with medication monitoring using an artificial intelligence-based smartwatch. Methods: Giorgi's descriptive phenomenological methodology was applied to collect and analyze data from November 9 to December 23, 2021. The study samples were recruited by convenience sampling, and even patients with diabetes participated in in-depth interviews via video conference and telephone calls or face-to-face visits. Results: Ten sub-themes and four themes were finally revealed. The four themes were as follows: journey with unfamiliar devices, a less-than-acceptable smartwatch, insufficient functions and content for patients with diabetes to use, and efforts for regular medication behaviors and daily monitoring of patient's health conditions. Conclusion: To effectively manage diabetic conditions using digital healthcare technologies, nursing interventions were needed to identify personal needs and consider technological, psychological, aesthetic, and socioeconomic aspects of wearable devices.

• 대한물리의학회지
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• 제14권1호
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• pp.53-61
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• 2019

PURPOSE: This study examined the dynamic range of motion (ROM) of the hip, knee, and ankle joint when wearing different shoe sole lifts, as well as the limb asymmetry of the range according to the leg length discrepancy (LLD) during normal speed walking. METHODS: The participants were 40 healthy adults. A motion analysis system was used to collect kinematic ROM data. The participants had 40 markers attached to their lower extremities and were asked to walk on a 6 m walkway, under three different shoe lift conditions (without an insole, 1 cm insole, and 2 cm insole). Visual3D professional software was used to coordinate kinematic ROM data. RESULTS: Most of the ROM variables of the short limbs were similar under each insole lift condition (p>.05). In contrast, when wearing a shoe with a 2 cm insole lift, the long limbs showed significant increases in flexion and extension of the knee joint as well as; plantarflexion, dorsiflexion, pronation, eversion, and inversion of the ankle joint (p<.05). Of the shoes with the insole lifts, significant differences in all ROM variables were observed between the left and right knees, except for the knee internal rotation (p<.05). CONCLUSION: As the insole lift was increased, more ROM differences were observed between the left and right limbs, and the asymmetry of the bilateral lower limbs increased. Therefore, appropriate interventions for LLD are needed because an artificial mild LLD of less than 2.0 cm could lead to a range of musculoskeletal problems of the lower extremities, such as knee and ankle osteoarthritis.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1990년도 추계학술대회
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• pp.1-4
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• 1990