• 전기의세계
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• v.29 no.1
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• pp.21-27
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• 1980

The effect of electric shock on human body is enormousness, which leads to warmth, tingling, and even death. The mean values of perception currents obtained on 91 men and 39 women are about 0.77(mA) for men and 0.57(mA) for women. The mean value for women is approximately seven tenths that of men. An individual can tolerate, with no adverse effects, repeated exposure to the reactions associated with currents of his let-go level, and the mean value of let-go currents obtained from 27 normal men is 6.29(mA). Lethal currents flowing human body is very dangerous even for a short time. So, it is necessary to have recourse to animal experiments ot determine lethal current for human. An analysis of experimental data indicates that body weight and shock duration are important factors in determining the lethal current. It is suggested that the relationship between current and shock duration is given by I=K/.root.T, and lethal current is proportional to body weight, where I is the current in milliampere, and T is the time in seconds.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.546-550
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• 2008

Impulsive excitation on vehicles produces shock-type vibration on the seat, usually which has major frequencies and damping ratios dependent on the characteristics of the suspension, the tire, the seat cushion and so on. The response of single degree of freedom model to a half-sine force input was considered as simple shock-type vibration signal. The quasi-apparent-mass for fifteen subjects was obtained with the shock-type vibration generated on the rigid seat, so its nonlinearity was found over 6.3 Hz according to the difference of magnitude of the shocks.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.230-230
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• 2011

대기압 플라즈마 제트 장치의 분출구 크기에 따른 플라즈마 분출 특성을 조사한다. 플라즈마가 분출되는 홀 모양의 방전관 출구의 직경 0.2, 0.5, 0.7, 1.0 mm에 대하여 비교 실험하였다. 플라즈마 제트 장치는 원통형 바늘 전극을 유리관 속에 삽입하고, 가스가 주입되는 형태이이다. 방전 가스는 Ar을 사용했으며 유량은 5 lpm이다. DC-AC 인버터를 사용하여 주파수 45 kHz 수 kV의 고전압을 인가하여 플라즈마 제트 장비를 구동한다. 직경이 작을수록 방출되는 플라즈마가 가늘고 방전 전압이 낮다. 직경이 작을수록 분출량 미세 조절이 용이하고 또한 낮은 방전 전압으로 인체 실험에 적용하는 경우에 전기적 충격이 적을 것으로 예상된다.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.491-498
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• 1995

A numerical human head/neck model was constructed for analyzing the implication in decleration injuries. This model consists of nine rigid bodies representing the head, cervical vertebrae C1-C7, and T1. These rigid bodies were connected by intervertebral disks described by massless beam elements. Muscles and ligaments were also incoperated in the model represented by nonlinear spring and viscoblastic element respectively Agreement of the analytical kinematic response with the results of experimental data from a volunteer run was satisfactory. Moreover, possible injury estimation from the calculated moment, force variations in the disc, and force variation in ligaments matched well with clinical observations.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.1
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• pp.67-71
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• 2010

Impingement of a high power laser pulse (above 1 GW/$cm^2$) on a metal foil causes its ablation, which is characterized by a rapid expulsion of matter and the initiation of a strong shock wave inside the solid metal. The shock propagates through the foil and reverberates on the rear side, causing its deformation and microparticle ejection, which were deposited on the foil prior to ablation. Based on this principle, we are developing a new drug delivery system - Biolistic gun. Current study is focused on the controllability, stability, efficiency of the system, and characterization of the penetration shapes in various conditions. We have tested the system by applying direct and confined ablation. Several different media combinations were used for confinement-BK7 glass, water, BK7 glass with water, and succulent jelly(ultrasono jelly, RHAPAPHRM). Biological tissue was replicated by a 3% gelatin solution. Present data shows that the confinement results in enhancement of penetration shape reached by 5 um cobalt microparticles. Based on the analysis of the experimental results we observe that the penetration shape of microparticles can be controlled by adjusting the thickness of confinement media.

• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.5-12
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• 2015

Since blasting noise is impact noise, it will give a sudden shock to the human. In the case, such as the blast vibration, it has given aging buildings and livestock great damage to move the vibration along ground in nearby regions. In this study, the influence of the blasting generated during excavation was analyzed for effects on regional. A couple of field and laboratory surveys about geological were carried out to figure out the geological ratio in the study-performed area. Blast vibration noise was compared to the domestic and abroad case studies and each of the institutions permissible standards established the most appropriate criteria in site condition. The vibration velocity of blasting vibration exploits the values which were measured from test blasting on the ground in order to examine blasting effect. Considering the blasting point as the shortest distance from safety facilities (farms, private houses, etc.), the examination of the influence range, which was derived from the vibration velocity of blasting vibration, was performed to figure out how the point affected the safety facilities. Three-dimensional numerical analysis was performed a time history analysis in order to analyze the behavior of the structure for a dynamic blast load, which was determined in three directions of the blast vibration value. The results of three-dimensional numerical analysis and the blasting effect of blasting vibration estimation equation blasting vibration of impact circle with accompanying test blasting were compared. And the analysis confirmed similar results figures.

• Journal of Haehwa Medicine
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• v.21 no.2
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• pp.95-104
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• 2013

스트레스로 인한 인체의 반응은 중추신경계, 시상하부, 변연계 및 기타 표적기관으로부터 시작되는데, 자율신경계 반응, 내분비계 반응, 면역계 반응 등을 통하여 복합적인 신체 증상으로 발현되며, 스트레스 상황에서는 시상하부-뇌하수체-부신 축 (HPA axis)과 교감신경계의 작용으로 여러 신경전달물질 방출에 변화가 생기며 이러한 변화는 면역기전에 중요한 역할을 하고 일부는 면역세포의 활성에 직접적으로 영향을 미쳐 신체 각종 질병의 원인이 될 것으로 추정된다. 한의학에서는 천인상응(天人相應)의 관점에서 육기(六氣)를 생체자극의 외적 요인으로 간주하고, 생체내적 현상인 정신이 외적 자극을 통하여 나타나는 생체반응을 칠정(七情)으로 보았으며, 이러한 관점에서 스트레스는 신체에 오장(五臟)의 허실(虛實), 혈허(血虛), 정손(精損), 기역(氣逆), 기(氣)의 순환장애, 담연(痰涎), 화(火) 등의 병적인 요인을 만들어 준다. 본 연구에서 재료로 사용된 호초 (Piper nigrum Linne)는 후추나무의 과실을 말린 것으로서 세계적으로 널리 사용되는 향신료이며, 한의학에서는 온중제한하기(溫中除寒下氣), 쾌격소담(快膈消痰), 해독(解毒)등의 효능으로 한담식적(寒痰食積) 완복냉통(脘腹冷通) 곽란(癨亂) 토사(吐瀉)등의 치료에 활용되어 왔다. 특히 쾌격소담(快膈消痰)하는 작용은 정신적 스트레스에 유효할 것으로 생각되므로 본 연구에 이용하게 되었다. 실험동물은 ICR계 생쥐를 이용하였으며, 심리적 스트레스는 옆쪽 cage에서 다른 마우스의 신체에 가해지는 전기 충격을 하루 1시간 동안 지켜보게 하는 것으로 유발하였으며, 이 상태에서 약물을 투여한 그룹을 실험군, 그렇지 않은 그룹을 대조군으로 하였다. 정상군은 아무런 자극 없이 하루 1시간 동안 일정 공간에 가두어 두는 것으로 하였다. 실험 결과, 호초(胡椒) 추출물을 100mg/kg/day 용량으로 5일간 투여한 실험군은 아무런 처치를 하지 않은 대조군에 비해 혈장 중 corticosterone 함량이 유의하게 감소되었고, 뇌에서의 noradrenalin 분비량이 유의하게 증가되었으며, plus maze test에서의 머무름 시간이 연장되는 것으로 나타나 호초(胡椒)가 심리적 스트레스를 효과적으로 억제하고 진정작용이 있는 것으로 사료되나 구체적인 작용기전 및 인체에서의 효과에 대해서는 향후의 보다 자세한 연구가 필요할 것으로 생각된다.

• Journal of the Korea Institute of Building Construction
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• v.11 no.1
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• pp.29-34
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• 2011

Since the study of building performance design was first undertaken by Building Research Station in 1930s, the results of such study has been reported from many parts of the world, building construction codes and standards have been revised based on performance in advanced nations as well in Korea, and various performance certification systems are in operation. The purpose of this study is to build a database of performance certification systems to investigate the co-relationship of various test methods related to the same test items. As test methods for case study, we selected test methods involving collision of the human body. Through analysis of Critical fall height test of EN 1177 and Head Model test of JIS A 6519 about 8 species of floor test-bodies, it was found that there are limits of application in terms of the depth and strength of cushion. Furthermore, although the measured physical parameters are the same, when the co-relationship between test methods is uncertain, the various physical parameters may not be compatible with the results.

• Journal of Biomedical Engineering Research
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• v.24 no.6 s.81
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• pp.501-507
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• 2003

Medical devices for helping the rehabilitation of the patients such as orthoses and prostheses should be designed to be strong enough. For the strength design, operational load should be identified first. Furthermore. medical devices are susceptible to dynamic load or shock frequently due to its characteristics. These type of the load may be identified by installing the sensors directly. However, it can modify the natural properties of the structures. Therefore, operational load should be identified indirectly from the system characteristics and responses such as vibrations. In this paper, the basic formulation of the indirect load identification is reviewed and the problems of conventional approach are checked. Then, the new approach based upon the principal component analysis is proposed and the validity of the proposed method is demonstrated using experiments.

• Journal of Biomedical Engineering Research
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• v.24 no.1
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• pp.15-21
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• 2003

In this study, for a safetv assessment of light weight wheelchair occupant in frontal crash, we tested a dynamic sled impact test. we carried out total 6 times test and impact speed was 20g/48 km/h. By using Hybrid III 50%ile male dummy, head injury criteria(HIC), neck flexion moment, neck axial tension force, neck shear force. chest acceleration, head, wheelchair and knee excursion were measured, we evaluated light weight wheelchair occupant safety by motion criteria(MC) which proposed in SAE J2249 and combined injury criteria(CIC) which is a voluntary standard(GM-IARV) of General Motors Co.. when we assumed that the maximum injury value in frontal crash was 100%, the result of motion criteria(MC) of wheelchair occupant was 52%, occupant upper body injury index(CIC) was 60.1%.