• 제목/요약/키워드: Physical length unit

검색결과 78건 처리시간 0.03초

가상환경에서의 실세계 물리적 길이 비교 (Real-World Physical Length Comparison in Virtual Environments)

  • 정철희;임창혁;이민근;이명원
    • 한국컴퓨터그래픽스학회논문지
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    • 제13권3호
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    • pp.19-24
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    • 2007
  • 본 논문에서는 가상환경의 물체들을 정확하게 비교하기 위하여 실세계 모든 길이 단위를 이용하여 물체의 길이를 정의하는 방법을 기술한다. 본 연구에서 브라우저는 화면상에 물체를 보여줄 때 모델러가 정의한 물리적 길이 속성을 참조하여 제작자가 원하는 길이로 물체를 표현한다. 서로 다른 모델러에서 제작된 서로 관계없는 물체들이라도 길이 명세를 가지고 있으면 브라우저에 들어 올 때 그에 따라 스케일이 적용되어 정확한 크기 비교가 가능하게 된다. 본 논문에서의 길이 명세는 X3D 명세에 추가하여 정의되었으며 포함되는 길이 단위는 $10^{-24}(yotta)$부터 $10^{24}(yocto)$ 까지이다. 그리고 서로 다른 LOLD(Levels of Length Detail) 속성을 가진 물체를 동시에 불러 올 때의 LOD(Levels of Detail) 처리와 LOLD 속성을 적용하는 방법에 대해 기술한다.

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관성센서 기반 신발형 보행 분석기의 신뢰성 연구 (Reliability of 3D-Inertia Measurement Unit Based Shoes in Gait Analysis)

  • 주지용;김영관;박재영
    • 한국운동역학회지
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    • 제25권1호
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    • pp.123-130
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    • 2015
  • Purpose : The purpose of this study was to investigate the reliability of 3D-inertia measurement unit (IMU) based shoes in gait analysis. This was done with respect to the results of the optical motion capturing system and to collect reference gait data of healthy subjects with this device. Methods : The Smart Balance$^{(R)}$ system of 3D-IMU based shoes and Osprey$^{(R)}$ motion capturing cameras were used to collect motion data simultaneously. Forty four healthy subjects consisting of individuals in 20s (N=20), 40s (N=13), and 60s (N=11) participated in this study voluntarily. They performed natural walking on a treadmill for one minute at 4 different target speeds (3, 4, 5, 6 km/h), respectively. Results : Cadence (ICC=.998), step length (ICC=.970), stance phase (ICC=.845), and double-support phase (ICC=.684) from 3D-IMU based shoes were in agreement with results of optical motion system. Gait data of healthy subjects according to different treadmill speeds and ages were matched to previous literature showing increased cadence and reduced step length for elderly subjects. Conclusion : Conclusively, 3D-IMU based shoes in gait analysis were a satisfactory alternative option in measuring linear gait parameters.

Effects of Resistance Exercise with Pressure Biofeedback Unit on the Gait Ability and Knee Joint Function in Subject with Total Knee Replacement Patients

  • Jin Park
    • The Journal of Korean Physical Therapy
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    • 제36권1호
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    • pp.27-32
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    • 2024
  • Purpose: This study was conducted to verify the effect of applying a pressure biofeedback unit on walking ability and knee joint function while performing knee joint extensor strengthening exercises using resistance exercise equipment in total knee replacement (TKR) patients. Methods: This study was conducted on twelve patients receiving rehabilitation treatment after being admitted to a rehabilitation hospital post-TKR. Of these, six were allocated to a feedback group with a pressure biofeedback unit, and the other 6 were allocated to a control group without a pressure biofeedback unit. The subjects performed an exercise program for 45 minutes per session, five times a week, for two weeks. Walking ability and knee joint function were evaluated and analyzed before and after exercise. Results: The feedback group showed significantly better improvements in walking speed, gait cycle, step length on the non-operation side, time on the foot on the operation side, K-WOMAC stiffness, and K-WOMAC function than the control group (p<0.05). Conclusion: When strengthening the knee joint extensor muscles using resistance exercise equipment in TKR patients, the provision of a pressure biofeedback unit was found to improve walking ability and knee joint function by inducing concentric-eccentric contraction of the knee joint extensor muscles. Therefore, the study shows that exercise based on the provision of a pressure biofeedback unit should be considered when strengthening knee joint extensor muscles to improve the walking ability and knee joint function of TKR patients in clinical practice.

Factors Influencing Discharge Destination and Length of Stay in Stroke Patients in Restorative Rehabilitation Institution

  • Gyu-Bum Lee;Jee-Sun Lee;Jeong Soo Kim
    • 한국전문물리치료학회지
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    • 제31권1호
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    • pp.48-54
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    • 2024
  • Background: Promoting patients' safe return home at discharge and reducing length of stay in hospital is key for Restorative Rehabilitation Institution (RMI). Objects: This study was designed to identify the factors influencing the return to home and length of stay among various factors. Methods: A total of 120 stroke patients (76 males and 44 females) who were hospitalized in an adult inpatient unit of a RMI for more than 2 months were retrospectively analyzed for this study (multivariate logistic regression analyses, p < 0.001). As predictor variables for assessing the return to home and length of stay, demographic data (sex, age, duration between onset and admission, length of stay, caregiver after discharge, occupation after discharge, reason for discharge, and household type after discharge) were collected. Additionally, following measurements were selectively collected from patient's medical records: scores of Mini-Mental State Examination Korean version (K-MMSE), modified Barthel Index Korean version (K-MBI), Berg Balance Scale and Functional Ambulation Category were obtained at admission and discharge. Results: The K-MMSE at admission and K-MBI at discharge were found to be the predictors of return to home. Additionally, K-MBI at admission influenced the length of stay. Conclusion: This study suggests cognitive functioning at admission and the level of activities of daily living at discharge predicted the return to home and length of stay.

Probabilistic Modeling of Fiber Length Segments within a Bounded Area of Two-Dimensional Fiber Webs

  • Chun, Heui-Ju
    • Communications for Statistical Applications and Methods
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    • 제18권3호
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    • pp.301-317
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    • 2011
  • Statistical and probabilistic behaviors of fibers forming fiber webs of all kinds are of great significance in the determination of the uniformity and physical properties of the webs commonly found in many industrial products such as filters, membranes and non-woven fabrics. However, in studying the spatial geometry of the webs the observations must be theoretically as well as experimentally confined within a specified unit area. This paper provides a general theory and framework for computer simulation for quantifying the fiber segments bounded by the unit area in consideration of the "edge effects" resulting from the truncated length segments within the boundary. The probability density function and the first and second moments of the length segments found within the counting region were derived by properly defining the seeding region and counting region.

요통환자의 자세동요와 동적기립균형에 관한 연구 (A Study of Postural Sway and Dynamic Standing Balance with Low Back Pain)

  • 양대중;송태호;임호용;안연준;박승규;김영록
    • 대한물리치료과학회지
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    • 제11권2호
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    • pp.18-26
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    • 2004
  • The purpose of this study was to compare difference of the static and dynamic balance in normal subject and LBP subject and recognizes about postural sway. The subjects of this study included 30 normal subjects and 30 LBP subjects. By using Active balance system, the static balance was measured by unit path length, circumference area, weight bearing, stabilometry length, while the dynamic balance was measured by step evaluation. Statistically analyzed using independent t-test to search static balance and dynamic balance difference in two groups. Postural sway appeared greatly in patient group than normal group in analysis result of static balance and postural sway was big in patient group of when closed eye and normal group and patient group did show statistical significance in unit path length, circumference area. Weight support of normal group was shared equally in weight bearing rate, but weight support of patient group stewed less to pain side. Anterior step time and Task achieve time of dynamic balance were spent more in patient group than normal group. Desire to be used to useful information to lay treatment policy about set-up and action of when quantification result of valued postural balance treats low back pain patient by objective tool, in the fixture, more researches in postural estimation desire that is enforced abuzz.

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우리나라 관개용 흙댐 저수지의 외형적 제특성에 관한 연구 (A Study on the Physical Characteristics of Irrigation Reservoirs in Korea)

  • 정두희;안병기
    • 한국농공학회지
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    • 제25권4호
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    • pp.29-37
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    • 1983
  • This study was carried out not only to prepare available materials that can be utilized in basic planning of irrigation reservoirs, but also to contribute to the study on countermeasures for reasonable irrigation water development in Korea in the future, through the investigation for the structural characteristics of reservoirs and their change trend by an epoch. During this study 123 sites of sample reservoirs were analysed in their dimensions of physical constituent factors. The physical characteristics and their change trends revealed by this study are summarized as follows: 1. For the irrigation earth dam in Korea the correlation between dam volume (v) and dam height & length (H$^2$L) can be described as the formula of v=1. 434H2L~17, 300 (r=0. 933), from which embankment amount is assumed to be quickly estimated under determined dam height and length of the proposed reservoir. 2. The ratio of dam volume to dam height & length ranges approximately from 0.5 to 3 (1.7 in average), that of storage capacity to dam volume 2 to 10 (8.4 in average), that of irrigation area to full water surface area 5 to 20 (13 in average) and that of catchment area to irrigation area 2 to 5 (4 in average). Though correlation between dam volume and dam height & length is high, that between others is relatively low. 3. Average storage depth ranges approximately from 4m to l0m (6.6m in average), unit storage capacity 0. 4m to 0. 8m (0.54 in average) and shape factor of dam 5 to 20 (10.5 in average). 4. The more recently planned the reservoirs were, the less storage capacity, dam volume, full water surface and dam shape factor they have. 5. The more recently planned the reservoirs were, the larger storage depth and unit storage capacity they have.

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골격근의 구조와 생역학에 관한 고찰 (A Review of Structure and Biomechanics of the Skeletal Muscle)

  • 공원태
    • 대한정형도수물리치료학회지
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    • 제13권1호
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    • pp.58-66
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    • 2007
  • The purpose of this study is to understand the structure and biomechanics of the skeletal muscle. The skeletal muscle takes 40 to 45% of the whole body. Stable posture requires a balance of muscle. However, when the muscle strength is unbalanced, movement initiates. The power generated by the muscle is a primary means to adjust the equilibrium of posture and movement. The structural unit of the skeletal muscle is a long cylindrical type muscle fiber which contains hundreds of nucleus. The thickness of muscle fiber is about $10-100{\mu}m$, and its length is about 1-50cm. Muscle fiber is composed of myofibril that is covered with plasma membrane which is called sarcolemma. In understanding the movement of human body, it is important to comprehend the movement of bone and joint and the tension of muscle. Understanding the structure and biomechanics of muscle also provides basic information on clinical treatment of patients.

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정상인에서 수동적인 뻗은다리올림 시 생체되먹임 장치의 압력과 허리골반 움직임의 상관관계 (The Correlation of the Pressure of Biofeedback Unit and Lumbopelvic Motion During Straight Leg Raising in Healthy Subjects)

  • 정도영
    • 한국전문물리치료학회지
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    • 제25권3호
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    • pp.12-18
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    • 2018
  • Background: Passive straight leg raising (PSLR) is the common clinical test to measure of hamstring muscle length. Hip flexion angle contributes to change the lumbopelvic rotation during PSLR. Pressure biofeedback unit (PBU) is commonly used to detect lumbopelvic movement during lower limb movements. Thus, there may be the relationship between pressure of PBU and lumbopelvic motion during PSLR. Objects: The objective of this study was to determine the relationship between pressure of PBU and lumbopelvic motion during PSLR. Methods: Thirty two subjects participated in this study. A three-dimensional motion analysis system were used to measure the lumbopelvic angle during PSLR, while recording the pressure of PBU according to angle of PSLR by 10 degree increments. Pearson product moment correlations and linear regression analysis were used to describe the relationship between variables. Results: The results showed that there was a significant relationship between the lumbopelvic and angle of PSLR (Pearson's r=.83, p<.05), between the pressure of PBU and angle of PSLR (Pearson's r=.75, p<.05), and between lumbopelvic motion and pressure of PUB (Pearson's r=.83, p<.05). Linear regression equation using lumbopevic angle as an independent factor was as follows: Pressure of PBU = 47.35 + (2.55 ${\times}$ angle of lumbopelvic motion) ($R^2=.69$, p<.05). Conclusion: Results of the present study indicate that pressure of PBU can be used to indirectly detect the amounts of lumbobevic motion during muscle length test or stretching of hamstring.

수축 보상 모르타르의 현장 적용 연구 (An Application of Shrinkage Compensation Mortar in Construction Field)

  • 김기동;정성철;송명신;이경희
    • 콘크리트학회논문집
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    • 제12권3호
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    • pp.3-10
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    • 2000
  • In this study, we compared a plain mortar with the CAS-system shrinkage compensation mortar for Ondol that is Korean traditional heating system. The Ondol mortar is necessary to have properties as non-crack, fine flatness and stability for thermal changes. especially, mortar'crack prevention is to be most important property in Ondol mortar. To develope the stable material on the crack-prevention, we used to calcium-sulfo-aluminate(CSA)system in shrinkage compensation mortar. And so, we confirmed the effects of calcium-sulfo-aluminate(CSA) system for mortar's physical properties such as setting time, compressive strength and expansion ratio for crack prevention. The initial and final setting time of the CSA mortar is faster than plain mortar about 2hours. And, Compressive strength increased about 20% that plain mortar. The crack length per unit area, plain mortar is 0.426∼0.481m/m2. The Results of apartment construction field test, the shrinkage compensation mortar is excellent about the crack-reduce effect.