• 제목/요약/키워드: three legs

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고장이 존재하는 육족 보행 로봇을 위한 대수적 힘 분배 (Algebraic Force Distribution in Hexapod Walking Robots with a Failed Leg)

  • 양정민
    • 한국지능시스템학회논문지
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    • 제19권4호
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    • pp.457-463
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    • 2009
  • 본 논문에서는 육족 보행 로봇의 새로운 힘 분배 알고리듬을 제안한다. 본 논문에서 고려하는 육족 보행 로봇은 다리 하나에 관절고착고장이 발생하여 내고장성 정적 세다리 걸음새로 보행한다. 제안되는 힘 분배 알고리듬의 핵심은 내고장성 걸음새가 가지는 안정여유도를 결정하는 지지 다리의 미끄러짐을 최소화시키는 것이다. 불연속적으로 움직이는 내고장성 세다리 걸음새는 정상 걸음새보다 안정도가 떨어진다는 약점이 있다. 본 논문에서 제안하는 힘 분배 알고리듬은 이러한 약점을 고려하여 내고장성 걸음새의 지지 다리가 세 개라는 성질과 Zero-Interaction Force 원리를 이용하여 최적화 기법을 쓰지 않고 대수적으로 모든 다리의 힘 성분을 구한다. 컴퓨터 시뮬레이션 사례 연구를 통해서 제안된 힘 분배 알고리듬과 기존 방법의 비교 분석을 실시하고 제안된 방법의 효용성을 입증한다.

스키에 의한 전방십자인대 손상에 대한 고찰 (The study of anterior cruciate ligament injury after a ski accident)

  • 박주환;전성화;양난희;김용권;김지혁
    • 대한물리치료과학회지
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    • 제10권1호
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    • pp.222-231
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    • 2003
  • The ACL(Anterior cruciate ligament) is the smallest of the four main ligaments of the knee, but it is the primary stabilizer. Injuries have a tendency to occur when the foot is firmly planted and the knee is twisted. Any sports that requires acceleration, change of direction and deceleration can increase the chances of suffering an ACL tear. The incidence of severe knee sprains that involve the ACL are at an all-time high. Since 1980, the number of these injuries have increased at least three-fold. Although the rate of increase has been much less dramatic since the middle 1980s, even the ultra-modem releasable ski binding has not been able to start reducing the incidence of ACL injuries. An ACL injury prevention program developed for downhill skiers by the Vermont Safety Research group emphasized increasing awareness of situations that can potentially result in an ACL injury and pre-planning strategies if events, leading to these situations, begin to fall in place. As part of the above study by Ettlinger et al., an educational prevent program was developed to teach these principles and thus reduce the rate of serious knee injuries. Four thousand instructors and patrol at 20 ski resorts who received the training had a 62% decline in serious knee injuries compared to a similar group that did not receive this training. Whenever you fall, try not to fully straighten your legs. Don't try to get up until you've stopped sliding(unless you are try to avoid an obstacle or other skier). When you're down, stay down. And don't land on your hand. So, if you feel yourself falling: arms forward, ski plates together, hands over knee. Then you will be able to save your ACL.

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폐장 및 신경근계를 침범한 Churg-Strauss 증후군 1예 (A Case of Churg-Strauss Syndrome Affecting Lung and Neuromuscular System)

  • 송현주;차주현;이진화;이지아;성순희;구혜수;김유경;장중현
    • Tuberculosis and Respiratory Diseases
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    • 제53권2호
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    • pp.183-189
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    • 2002
  • 저자들은 기침, 객담, 그리고 양측 하지의 부종과 저린감을 주소로 내원한 환자를 신경과 근육의 조직 검사를 시행하여, 폐장 및 신경근계를 침범한 Churg-Strauss 증후군으로 확진하여 스테로이드로 성공적으로 치료한 1 예를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

다운증후군 아동들의 보행 비대칭성 연구 (Gait Asymmetry in Children with Down Syndrome)

  • 임비오;한동기;서정석;은선덕;권영후
    • 한국운동역학회지
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    • 제16권2호
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    • pp.145-151
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    • 2006
  • A large interindividual variability and some abnormally kinematic patterns at the lower extremity were the main features of the gait in children with Down syndrome. The purposes of this study were to investigate the gait asymmetry and biomechanical difference between dominant leg and non dominant leg in children with Down syndrome. Seven boys with Down Syndrome(age: $120{\pm}0.9yrs$, weight $34.4{\pm}8.4kg$, leg length: $68.7{\pm}5.0cm$) participated in this study. A 10.0 m ${\times}$ 1.3 m walkway with a firm dark surface was built and used for data collection. Three-dimensional motion analyses were performed to obtain the joint angles and range of motions. The vertical ground reaction forces(%BW) and impulses($%BW{\cdot}s$) were measured by two force plates embedded in the walkway. Asymmetry indices between the legs were computed for all variables. After decision the dominant leg and the non dominant leg with max hip abduction angle, paired samples t-test was employed for selected kinematic and ground reaction force variables to analyze the differences between the dominant leg and the non dominant leg. The max hip abduction angle during the swing phase showed most asymmetry, while the knee flexion angle at initial contact showed most symmetry in walking and running. The dominant leg showed more excessive abduction of hip in the swing phase and more flat-footed contact than the non dominant leg. Vertical peak force in running showed more larger than those of in walking, however, vertical impulse showed more small than walking due to decrease of support time. In conclusion, the foot of dominant leg contact more carefully than those of non dominant leg. And also, there are no significant difference between the dominant leg and the non dominant leg in kinematic variables and ground reaction force due to large interindividual variability.

이질바퀴에 대한 처리방법에 따른 살충제 감수성 (Susceptibilities of american cockroach, Periplaneta americana to insecticides according to application methods)

  • 한종빈;배정숙;김길하
    • 농약과학회지
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    • 제8권3호
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    • pp.210-219
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    • 2004
  • 시판되고 있는 61종 살충제와 바퀴전문약제 2종에 대한 식이법으로 이질바퀴 (Periplaneta americana) 수컷성충의 우수 살충제를 탐색하고, 활성이 있는 약제를 이용하여 처리부위와 검정법에 따른 감수성 차이와 발현속도를 비교하였다. 식이법에서 100%의 살충률을 나타낸 dichlorvos, benfuracarb, cypermethrin, deltamethrin, fenpropathrin, $\zeta$-cypermethrin, $\lambda$-cyhalothrin, fipronil등 8종 약제를 선발하여, 식이법과 여지접촉법으로 살충력을 비교한 결과, dichlorvos와 fenpropathrin은 여지접촉법에서, benfuracarb는 식이법에서 더 높은 감수성을 나타내었다. 미량국소처리법으로 처리부위 (머리, 가슴, 배, 다리)에 따른 약제비교에서는 dichlorvos, benfuracarb, $\lambda$-cyhalothrin은 머리에서, deltamethrin, cypermethrin, fenpropathrin은 배에서 감수성이 가장 높았다. Dichlorvos, benfuracarb, $\lambda$-cyhalothrin의 $LT_{50}$ (일)은 각각 0.10, 0.29, 0.12로 속효성이었으며, boric acid와 byamethylnon은 각각 6.2와 4.8로 지효성이었다.

An Exploration of Various Evaluation Methods to Improve Usability of Museum Mobile Device

  • Ahn, Mi-Lee;Cha, Hyun-Jin;Hwang, Yun-Ja;Kim, Hee-Jin
    • 대한인간공학회지
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    • 제30권6호
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    • pp.765-773
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    • 2011
  • Objective: This study aims towards exploring a model of the HCI evaluation methods to improve the usability of mobile device, based on a case of a Mobile PDA system in a Museum context. Background: Mobile PDA systems in a Museum context is widely utilized for the educational purposes, but it is criticized for low usability that the device only play a role in textbooks on legs without any interactive educational activities. Therefore, the usability improvements on the mobile PDA system should be considered. Method 1: This model was developed with a combination of the expert review and the user testing, and with a combination of the qualitative and quantitative studies. In more details, first of all, a qualitative study was conducted as a combination of three different methods: 1) expert review with heuristics, 2) interviews with persons working in a museum, and 3) contextual enquiry. Results 1: The experts review provided with critical usability issues, and the semi-constructive interview helped to understand the background of the mobile device. Lastly, the contextual enquiry showed user experience problems and directions of improving the device from user's perspective. Method 2: Based on the results of the qualitative study, a questionnaire was designed. Results 2: The analysis of the quantitative study was conducted to generalize the problems, and prioritize the direction of improving the device within the limitation of the cost and time in a museum. Conclusion: This study has implications in developing an example of a HCI evaluation model to improve the user experience of the mobile device as well as finding problems and directions of how to improve the mobile PDA systems in the museum. Application: In fact, most of the studies related to the evaluation of the mobile device have been conducted in a laboratory context due to the cost and time. This paper, however, attempted to apply to various HCI research techniques from different constituents in real context.

현대 무용의상에 나타난 인체의 추상화에 관한 연구 - 오스카 슐레머의 의상이론을 중심으로 - (A Study on the Abstraction of the Human Body in Contemporary Dance Costumes - Focusing on Oscar Schlemer's Costume Theory -)

  • 한경하;금기숙
    • 복식
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    • 제60권10호
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    • pp.133-145
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    • 2010
  • The study used four basic formats classified based on the four principles on costumes discussed in the paper 'Human Beings and Arts Phenomena' by Oskar Schlemmer who studied the relationships between stage space and the human body as an analysis tool with regard to analyses on the abstraction of human body in contemporary dance costume. Abstraction of human body expressed in costume for contemporary dance is as follows: Expansions caused by unclear boundary between spaces and costumes, and the principles of three-dimensional abstract spaces based on a geometric cube change heads, trunks, arms and legs to achieve expansions. Similar mechanical shape is a type of shape made in a succession of functional principles of human body in relationships with spaces. As mechanical mechanism is added to the geometric transformation of a specific part of human body, mechanicalness is contained in it. Motion organisms are geometric simplification of moving traces in a space based on conversion into mechanical organisms based on principles of motion, and as mechanical rotation, consecutive speed caused by refraction and directionality are suggested, mobility is achieved. Immaterial shape is based on change into a metaphysical form, and it is converted into animals, plants or a third life that symbolize body parts. It has metaphysical significance in each body part and extends sensibility. As a result of the study, development into abstract succession and a techno art mode has been confirmed. Combination of geometric cubic figures with the organic human body and configuration of the human body pursued by Oskar Schlemmer's geometric abstraction through the proactive accommodation of mechanical aesthetics has been succeeded and expressed in the contemporary dance costumes.

전주장의 구조적 특징과 금구장식 연구 (A Study on the Structural Characteristics and Metal Ornament of Jeonju-Jang)

  • 백다희;임승택
    • 한국가구학회지
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    • 제28권3호
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    • pp.207-223
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    • 2017
  • Jeonju-Jang is the wood furniture that was made in Chonbuk Jeonju province during the Joseon Dynasty, and was used by middle-upper social classes. It has value as a local cultural heritage because it has unique characteristics in terms of the shape of the furniture, the metal ornament and various functions are integrated in accordance with user's requirements. Therefore, the purpose of this study is to define the structural characteristics of the Jeonju-Jang through case studies of 16 existing artifacts in order to preserve and inherit the value as local cultural resources. The conclusion is as follows. First, Jeonju-Jang in the late period of Joseon Dynasty that is made up of one board to the bottom with the binding of the board. and the front wall, the Juibyuckkan and the Meoruemkan are omitted or made small, so the structure of the surface is simple. There are three or four drawers under the Cheon pan(top plate). There are drawers and shelf inside the hinged door. In the case of a two-layer type, there is a Gaegumeong type door which has half of one side hinged. Second, Jeonju-Jang of the Japanese Ruling Era had a Juibyuckkan by frame binding and an increase in the number of Meoruemkan. and it had independent legs. The Cheon-pan(top plate) was more left and right than both sides. Third, in the late Joseon Dynasty period as a feature of the metal ornaments, cast iron and yellow brass were used as materials. In the Japanese Ruling Era, nickel was mainly used. Various patterns were engraved and the number increased, and it became gorgeous surface as a whole.

태권도 옆차기 동작의 운동학적 분석 (A Kinematical Analysis of Side Kick Motion in Taekwondo)

  • 박광동
    • 한국운동역학회지
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    • 제13권2호
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    • pp.49-63
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    • 2003
  • For this study, four male university Taekwondo players were randomly chosen, between the weight categories of 60Kg and 80Kg. Their side kicks (yeop chagi), which are part of foot techniques, were kinematically analyzed in terms of the time, angle, and angular velocity factors involved with the kicks through the three-dimensional imaging. The results of the analysis are as fellows. 1. Time factor The first phase(preparation) was 0.48sec on average, accounting for 60% of the entire time spent; the second phase(the minimum angle of the knee joint) was 0.21sec on average, taking up 26% of the whole time spent; and the third phase(hitting) was 0.11sec on average, representing 14% of the entire time spent. 2. Angle factor In the first phase(preparation), rotating their bodies along the long axis, the players bended their hip and knee joints a lot, by moving fast in the vertical and horizontal directions, in the second phase(the minimum angle of the knee joint), the players continued to extend their bodies along the vertical axis, while pronating their lower legs and bending their hip and knee joints a lot to reduce the radius of gyration, and in the third phase(hitting), they extended their knee joints greatly so that the angle movements of their lower bodies shifted to circle movements. 3. Angular velocity factor In the first phase(preparation), the angular velocity of the hip and knee joints increased. while moving horizontally and rotating the body along the long axis; in the second phase(the minimum angle of the knee joint), the angular velocity increased by bending the hip and knee joints fast to reduce the rotation radios; and in the third phase(hitting), the angular velocity was found to have increased, by rotating the body along the long axis to increase the angular velocity and shifting the angular momentum of the pronated knee joint to the circular momentum.

조영제 투여 후 초발한 저린감에 대한 사물탕가미(四物湯加味) 치료 증례보고 (A Case Report of Treatment of Numbness Associated with Contrast Medium Injection using Modified Samul-tang)

  • 권정연;배지용;공경환;고호연
    • 대한한방내과학회지
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    • 제40권5호
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    • pp.983-989
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    • 2019
  • Objective: Many types of delayed adverse reactions, such as long-term numbness, occur after injecting contrast medium, but few clinical studies have reported effective treatments for these reactions. We report that herbal medicine can have a positive clinical effect in patients who have experienced long-term numbness after contrast medium injection. Method: A patient who had felt numbness in her head and whole limbs presented at Semyung University Korean Medicine hospital. Her numbness had first started 2 days after injection of contrast medium, and she had felt it constantly for almost 2 years. After admission at the hospital, she took "modified Samul-tang" herbal medicine (120 cc three times per day) from 29 January 2019 to 2 February 2019. We measured her numbness using a numeric rating scale (NRS) on 29 January and 2 February and we compared both scores to determine the degree of favorable and clinical effects of herbal medicine. Result: The NRS score for numbness was 5 for her head and limbs on the first day (29 January), but after 4 days (2 February), the NRS score decreased to 0 for her head and both arms and hands, and it decreased from 5 to 2 for both her legs and feet. Conclusion: Korean herbal medicine can have positive clinical effects on treating adverse reactions due to injection of contrast medium.