• 한국통신학회논문지
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• 제34권9B호
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• pp.867-875
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• 2009

무선 신체망 (WBAN: Wireless Body Area Network)은 생체 신호를 검출하고 전송하기 때문에 인간의 생명과 직결되어 있다 그러므로 무선 신체망은 다른 망과 비교해 망의 신뢰성이 극도로 높아야 하기 때문에 이 신뢰성과 관련된 연구가 매우 중요한 분야로 부각되고 있다. 본 논문에서는 다중 오류 (multi-type failures) 가 발생한 무선 신체 망에서 노드의 오동작들에 대해 분석하고 오동작 분석에 대한 새로운 모델을 제시한다. 오동작 모델링을 위해, 각 노드들을 라우팅 기능의 유무에 따라 분류하고, 노드의 에너지가 완전 소비되었거나 노드가 악의적인 공격에 의해 오류가 발생되었을 경우 각 노드들의 동작을 세미 마르코프 프로세스 (Semi-Markov Process)를 이용하여 모델링하였다. 본 논문에서 제시된 모델은 다중 오류 (multi-type failures) 환경에서 무선신체망의 신뢰성 분석에 매우 유용하다.

• 한국전자파학회논문지
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• 제23권8호
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• pp.985-994
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• 2012

본 논문에서는 wireless body area network(WBAN) 채널을 분석하기 위해 실제 채널을 측정하고, 그것의 통계적 특성들을 조사하였다. On-/off-body 채널에서, 인체의 움직임을 고려하기 위해 대표적인 움직임들을 같이 측정하여 그 분석 결과들을 비교하였다. 또한, 세 종류의 신호 전송 기법을 제한된 Outage 확률을 가질 때 최소 소비 전력을 분석하여, 이론적인 총 전력 소비를 계산하였다. 그리고 채널 측정 데이터들을 통해 이론과 실제의 차이를 분석하였다. 본 논문의 결과로 협력 통신을 통하여 전송 효율을 높일 수 있음을 알 수 있으며, 센서 노드의 부착 위치와 움직임이 신호 전송 전력에 어떠한 영향을 미치는지 확인할 수 있다.

• 한국초지조사료학회지
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• 제16권3호
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• pp.235-244
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• 1996

This experiment was carried out to evaluate the effect of pasture type on behavior pattern, change of body type and daily gain of Korean native goat at the College of Natural Science of Kon-KuK University in Chungju. The results are summarized as follows : Relative coverage of native herbage at the pasture area was 62% in initial grazing period and that final grazing period decreased by 36%. while pasture plants increased from 17 to 42%. In brush area, Quercus serrata. Quercus dentutu, Prunus surgenrii and Rhus vemicrflua of high palatability decreased with increase in grazing period. but Rhododendron mucronulatum and Rhodendrorl schlippenbachii of low palatability tended to increase. Average crude protein content at the pasture area(12.3Q) during grazing period was higher than that at the brush area(10.2). However, ADF and NDF content was lower than brush area. Ca, Mg and Na of mineral content showed highly at the brush area during the grazing period. but Na showed highly at the pasture area. Eating time Korean native goat was not different between pasture area(369 min.) and brush area(361 min.), but ruminating time showed highly at the pasture area(441 min.). Average ratio of GTlRT at the pasture and brush area was not different m 0.88 and 0.87, respectively. All body type(withers height, body length, shin circum, hip height, hip width and chest girth) showed highly that pasture area compared to brush area during the grazing periods. The daily liveweight gain showed 60.6 and 48.98 at the pasture and brush area, respectively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권5호
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• pp.1094-1107
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• 2013

NTRU cryptosystem has been suggested for protecting wireless body area networks, which is secure in the sense of traditional cryptanalysis. In this paper, we fulfill the first power analysis attack on the ultra-low-power environment of wireless body area networks. Specifically, two practical differential power analyses on NTRU algorithm are proposed, which can attack the existing countermeasures of NTRU. Accordingly, we suggest three countermeasures against our attacks. Meanwhile, practical experiments show that although the attacks in this paper are efficient, our countermeasures can resist them effectively.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 1부
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• pp.674-678
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• 2008

본 논문은 WBAN(Wireless Body Area Network) 환경에 기반한 스마트 오브젝트(Smart Object)의 개발에 대한 논문이다. 다양한 기능을 가진 컴퓨팅 디바이스를 장착한 스마트 오브젝트가 많이 개발되면서, 사용자에게 가중되는 소지품으로써의 수많은 기기, 도구들을 사용자가 하나하나 관리하기에는 역부족이므로, 이를 분류하고 관리함으로써 사용자는 단순히 자신들이 가진 스마트 오브젝트의 기능만을 활용하게 해주는 스마트 오브젝트의 개인 네트워크 화하는 기기의 필요성이 증대된 가운데, 이러한 형태의 오브젝트를 개발함에 있어 어떠한 기술들이 필요하고 어떠한 요소들을 갖춰 설계 해 나가야 할지에 대한 최적화된 설계 기준을 분석하고 개발 방향을 제시하고자 한다.

• ETRI Journal
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• 제46권4호
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• pp.571-580
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• 2024

A compact triple-band porous electromagnetic bandgap structure-loaded coplanar-waveguide-fed wearable antenna is introduced for applications of wireless body area networks. The porous structure is aimed to create a stopband or bandgap in the electromagnetic spectrum and increase breathability. The holes in the bottom electromagnetic bandgap surface increase the inductance, which in turn increases the bandwidth. The final design resonates at three bands with impedance bandwidths of 264 MHz, 100 MHz, and 153 MHz and maximum gains of 2.18 dBi, 6.75 dBi, and 9.50 dBi at 2.45 GHz, 3.5 GHz, and 5.5 GHz, respectively. In addition, measurements indicate that the proposed design can be deformed up to certain curvature and withstand human tissue loading. Moreover, the specific absorption rate remains within safe levels for humans. Therefore, the proposed antenna can suitably operate in the industrial, scientific, and medical, Bluetooth, Wi-Fi, and WiMAX bands for potential application to wireless body area networks.

• 한국패션뷰티학회지
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• 제4권1호
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• pp.35-41
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• 2006

From 1995 to 2005 the information related to clothing and textiles publicized by 6 journals regarding Elder Women's body type was collected and analyzed. The results are as follows. 1. It has been investigated into the elder woman's body type since 1995, and this subject needs a detailed study. in audition, investigation into woman's body type has been studied parts of the body for clothing construction. 2. Analysis result for measure area preponderance(Seoul area and local metropolitan city) of area, measure subject number mainly to large scale group more than 300 people that measure is consisting most know can. 3. Where the way of measurement is concerned, there are direct measurements more than indirect measurements. In case of using just direct measurement, the study often mentions necessity of indirect measurements. Therefore it is thought simultaneous measurement is the most desirable. 4. A Body type characteristic of elder woman shows a size of every part diminishes as growing older. Owing mainly to obesity of waist and abdomen, they have a changed body a measure of around the abdomen is bigger than around the hips. hips drop and the upper half of the body down, and besides, feet are changed into the flat.

• 복식문화연구
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• 제2권2호
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• pp.385-394
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• 1994

Data of the body surface is a necessary unit for the measuring of metabolism energy and activity energy. And also, these data are referring to check the degree of retaining warmth of clothes, to find the effect of heat insulation according to body surface, to calculate an average temperature of skin, and to study the several fields of clothing. In measuring of body surface, it si actually impossible to measure a subject's body surface in each experiment. As the experimental method, both gypsum method, by which the shape of body an be copied as it is, and the weighting method from which planed body surface area can be measured with consistent thickness of polyprophylene film as used. In fact, every female subject feels uncomfortable to measure her body surface as a naked body. There, it is providing a simple, accurate regressive equation with weight & height as variable factors in this study. This equation is as=117.02W+77.31H-3344.94 with average error : 0.1%, absolute average error : 2.07%.

• 한국안전학회지
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• 제16권1호
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• pp.37-42
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• 2001

The severity of electric shock is entirely dependent on body resistance. When the human body becomes a part of electric circuit, the body resistance is given as a function of shock scenario. Factors which consist of applied voltage, shock duration, body current path and contact area, etc.. The body resistance is defined as the voltage applied to subjects divided by the body current. To secure safety of the subjects, the experiment is conducted on 10 subjects, the body current is limited to 4mA. And only three factors under many shock scenario conditions are used to determine the body resistance. The three factors are the applied voltage, the current pathway and the contact area. The object of this work is to estimate the dynamic resistance of the human body as a function of applied voltage using the body current at low-voltage levels. The data of the body current at low-voltage levels are extrapolated to high-voltage levels using two analytic functions with specified constants calculated by numerical method. Also we can provide permissible body voltage for various copper electrodes on the basis of the data determined with the dynamic resistance and the body current.

• 대한치과기공학회지
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• 제27권1호
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• pp.27-39
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• 2005

This study is to show the qualitative analytic methods of facial asymmetry with three-dimensional morphometry and find out asymmetry change resulted from enlarging three local regions. Steel balls (1.2mm in diameter) were attached in twenty seven landmarks of a symmetrical artificial human skull. This artificial human skull was used as experimental materials. Twelve different asymmetrical artificial human skulls were formed by gradually enlarging the mandibular body length, gonial angle, and ramus height of the left hemiface. From the three-dimensional morphometry of each skull type, nine local area measurements and three total sum area measurements(representing the mandibular area, maxillary area, and lower facial area) were acquired and made into the surface area asymmetry degree. Menton deviation itself was used as the surface area asymmetry degree while right-left percentages were used in the other measurements. These surface area asymmetry degrees were compared with each other to find out asymmetry change according to the degree of actual facial asymmetry. Through the statistical analysis, following results were obtained. The results were as follows: 1. Left maxillary area of artificial human skull was 7.13$\pm$0.26% larger while mandibular area was 4.14$\pm$0.12% smaller than each those of right hemiface. After all, left lower facial area was 1.44$\pm$0.07% larger than those of right hemiface.(n=7). 2. Among the reduce rates of surface area asymmetry degree resulted from enlarging three local regions, ramus height was similar to mandibular body length while it was bigger than those of gonial angle. 3. Among the increase rates of menton deviation resulted from enlarging the local regions, ramus height was the biggest, mandibular body length was the second and gonial angle was the smallest. These results suggest that three-dimensional morphometry can be used to qualitatively analyse facial asymmetry and the asymmetry degree is more influenced by enlarging the ramus height, mandibular body length than those of gonial angle.