• Title/Summary/Keyword: Motion Study

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A Study on Locational Control of Motion Ghost in Magnetic Imaging System (자기공명영상장치(磁氣共鳴映像裝置)에서 움직임허상(虛像)의 위치제어(位置制御)에 관(關)한 연구(硏究))

  • Lee, Who-Min
    • Journal of radiological science and technology
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    • v.16 no.2
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    • pp.19-26
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    • 1993
  • Magnetic Resonance Image represents three-dimensional diagnostic imaging technique using both nuclear magnetic resonance phenomenon and computer. Compared with computed tomography (CT), MRI have advantages harmless to patient's body, three-dimensional image with high resolution and disadvantages long data acquisition time because of long T1 relaxation time, relatively low signal to noise ratio, high cost of setting, also. As physiologic motion of tissue results in motion ghost in MRI, high 2.0Tesla make improve low signal to noise ratio. This study have aim to improve image quality with controling motion ghost of tissue. Supposing a moving pixel in constant frequency, one pixel make two ghosts which are same size and different anti-phase. So, this study will show adjust parameter on locational control of motion ghost. Author made moving phantom replaced by respiratory movement of human, researched change of motion frequency, FOV by location shift, and them decided optimal FOV (field of view). The results are as follows: 1. The frequency content of the motion determines how far the image always appear in phase-encoding direction, the morphology of the ghost image is characteristic of the direction of the motion and its amplitude. 2. Double FOV of fixed signal object for locational control of motion ghost is recommended. Decreasement of spatial resolution by increasing FOV can compensate on increasing of matrix in spite of scan time increasement.

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Statistical evaluation of drift demands of rc frames using code-compatible real ground motion record sets

  • Kayhan, Ali Haydar;Demira, Ahmet
    • Structural Engineering and Mechanics
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    • v.60 no.6
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    • pp.953-977
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    • 2016
  • Modern performance-based design methods require ways to determine the factual behavior of structures subjected to earthquakes. Drift ratio demands are important measures of structural and/or nonstructural damage of the structures in performance-based design. In this study, global drift ratio and interstory drift ratio demands, obtained by nonlinear time history analysis of three generic RC frames using code-compatible ground motion record sets, are statistically evaluated. Several ground motion record sets compatible with elastic design spectra defined for the local soil classes in Turkish Earthquake Code are used for the analyses. Variation of the drift ratio demands obtained from ground motion records in the sets and difference between the mean of drift ratio demands calculated for ground motion sets are evaluated. The results of the study indicate that i) variation of maximum drift ratio demands in the sets were high; ii) different drift ratio demands are calculated using different ground motion record sets although they are compatible with the same design spectra; iii) the effect of variability due to random causes on the total variability of drift ratio demands is much larger than the effect of variability due to differences between the mean of ground motion record sets; iv) global and interstory drift ratio demands obtained for different ground motion record sets can be accepted as simply random samples of the same population at %95 confidence level. The results are valid for all the generic frames and local soil classes considered in this study.

A Study on the Upper Body Range of Motion (Using a 3-D Motion Anlaysis System) about Korean Adults (한국 성인 남자의 상체 동작범위 연구 - 3D 동작분석 장치를 이용하여 -)

  • 박길순;유신아
    • The Research Journal of the Costume Culture
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    • v.8 no.4
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    • pp.587-601
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    • 2000
  • The purpose of this study : 1. The total 56 range measurements of active dynamic motion of 40 subjects (20's and 30's) were measured using 3-D dynamic motion analysis system. 2. Various comparisons were performed for the right and left side, male, age groups (20's, 30's, and 40's ∼ 60's) using previous studies. The results were compared with the other studies in the aspects of age. In this study, the 3-D motion analysis system based on photogrammetry was established and used to analyze the human's motion and posture. The system consists of VICON 140, data acquisition system, and data analysis program (KRISSMAS). The result of this study were as follows : 1. Comparing 20's with 30's the result shows that 30's have larger ROM at some joints, which is inconsistent with the previous result. The reason is that female subjects in 20's were improperly sampled according to the representatives of anthropometry characteristics. 2. There are significant differences in some joints related with age. 20's male subjects have more flexible joints in the neck while 30's male subjects have more flexibility in their shoulder joint and elbow joint. But most of the significances were not high (p〈0.05). The prediction that the right side of Korean bodies would be more flexible was not a good hypothesis. And the joints flexibilities are not correlated with Rohrer's Index.

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A Study on the Lower Body Range of Motion(Using a 3-D Motion Analysis System) about Korean Adults (한국성인 남자의 하체 동작범위 연구 - 3D 동작분석 장치를 이용하여 -)

  • 류신아;박길순
    • The Research Journal of the Costume Culture
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    • v.8 no.5
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    • pp.741-753
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    • 2000
  • The purpose of this study : 1. The total 24 range measurements of active dynamic motion of 40 subjects(20's and 30's, and 40's∼60's) using previous studies. The results were compared with the other studies in the aspects of age. In this study, The 3-D motion analysis system consists of VICON 140, data acquisition system, and data analysis program called by KRISSMAS. VICON 140 is dynamic motion analyzer, and KRISSMAS is a program developed for analysis of the data captured from the VICON. The results of this study were as follows : 1. Comparing 20's∼30's and 40's∼60's the result shows that 40's∼60's have smaller ROM at the most joints(Thoratic and Lumber, Hip Joint, Knee Joint, Ankle Joint), which is inconsistent with the previous result. The reason is that most investigations were carried out using traditional measurement equipments, which have encountered difficulty in quantifying the exact motion of the body. 2. There are no significant mean difference between the right and the left side. Most of the significances were not high(〉0.05).

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Wrist Motion in Computer Keyboard Typing

  • Han, Jung-Soo
    • Journal of Mechanical Science and Technology
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    • v.17 no.12
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    • pp.2004-2009
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    • 2003
  • The purpose of this study is to define how wrist motion is affected by different postures and supporting devices and to discover functional range of wrist motion for keyboard typing. The range of wrist motion (ROM) needed for fourteen experienced typists to type on a computer keyboard was measured by flexible and biaxial electrogoniometers. The most frequent wrist motion during typing was in extended and ulnarly deviated positions in both wrists. Range of wrist motion was similar in both wrists. The average ROM for keyboard typing with the typists' own posture was about 39 in flexion/extension (FEM) and 29 in radial/ulnar deviation (RUD) in both wrists. The range of wrist motion was significantly reduced to 30 in FEM and 27 in RUD with use of either wrist or forearm supporting devices, which suggests that these devices might help to relieve fatigue, discomfort, or pain during and/or after typing. Results of this study will be of interest to clinicians and helpful to those who are professionally or non-professionally involved in typing.

Development of Quantitative Diagnostic Technique for Low-Back Pain Patients via Three Dimensional Dynamic Motion Analysis (3차원 동작분석에 의한 요통환자의 정량적 진단기법 개발에 관한 연구)

  • Kim, Jeong-Ryong
    • Journal of the Ergonomics Society of Korea
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    • v.17 no.2
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    • pp.11-23
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    • 1998
  • Dynamic motion difference between normal subjects and low-back pain (LBP) patients has been investigated in terms of kinematic variables such as range of motion, velocity and acceleration of the back and hip. Ten healthy subjects and ten LBP patients were recruited in this study. Electro-goniometer such as Lumbar Motion Monitor and Hip Monitor have been used for quantitative measurement of the trunk motion during repetitive flexion and extension for ten seconds. Results indicated that the velocity and acceleration of the back and hip were important parameters to quantitatively identify LBP patients. The consistency of cyclic trunk motion and the relationship between the back and hip were measured in terms of Variance Ratio and Phase Angle in order to accurately assess the motion characteristics of LBP patients. In particular, the hip motion has been proven to be a very important factor in describing the kinematics of damaged lower back. The functional evaluation technique suggested in this study will be a tool to assist physicians for an accurate diagnosis and timely rehabilitation along with current image diagnosis techniques.

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A study on an improvement of the robot motion control by the robot ergonomics (Robot Ergonomic에 의한 로보트의 동작제어 개선에 관한 연구)

  • 이순요;권규식
    • Journal of the Ergonomics Society of Korea
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    • v.8 no.2
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    • pp.19-26
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    • 1989
  • This study, as a part of integrated human-robot ergonomics, improves the robot motion control on the robot task in the TOES/WCS whose purpose is improving the teaching task constructed in the previous study. First, the updated combined fuzzy process using a new membership function with Weber's law is constructed for the purpose of coordinate reading of the end points in the macro motion control. Second, an algorithm using the geometric analysis is desinged in order to calculate position values and posture values of the robot joints. Third, the MGSLM method is designed to remove unnecessary the robot motion control caused by the GSLM method in the micro motion control. Consequently, proposed methods in this study lessen burdcn of a human of an improvement of the robot motion control and reduce the teaching time of a human operator and inaccuracy of the teaching task, which contribute to the integrated human-robot ergonomics.

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A Study on Korean-Style Motion Prototype and Animation (한국적 애니메이션과 Motion Prototype 연구)

  • Koh Jae-Sung;Bae Soo-Am;Cho Dae-Jea
    • Proceedings of the Korea Contents Association Conference
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    • 2005.05a
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    • pp.285-288
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    • 2005
  • If the motion is universal over the differences between the ancient age and the modern age, and between primitiveness and civilization, It is required to be studied, which make it possible to discover the universally valid interpreting elements of various societies and cultural phenomena. The study on the motion, as a base of universal motion study on animation and character modelling is considered as a very important part. The sampled motion prototype was classified by the continuity and the synchronicity that is a basis of modular analysis and of motion flow. Koguryo's mural paintings in old tombs has been the heritage and the symbol of the nation's historical identity and pride in Korean history. Koguryo is obviously a part of Korean history, which are of Korean elements. Accordingly, the mural paintings that this study has explicated is the origin as well as the history of Korean visual animation history, while the analysed and restored motion prototype is a module of Korean motion with golden section proportion.

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Development of robot work measurement by the unit motion model (단위 동작 모형에 따른 로봇 작업시간 측정법의 개발)

  • 권규식
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.367-370
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    • 1996
  • This study deals with the motion modeling by the unit motion of robots and the work measurement through classification of robot motions and standardization. The proposed approach is to scrutinize the Predetermined Time Standards(PTS) methods for measurement of manual tasks performed by people and the basic motions for accomplishing that tasks. And then, it constructs the unit motion models as subsets composed with the basic motions. It apply together with movements distance as a time variable, too. These results are used for the work measurements of robots by the unit motion models.

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The Study of 3D Motion Analysis on Lower Limb during Walking with Walker on Older People (노인의 워커 사용에 따른 보행 시 하지 관절 3차원 동작 분석에 관한 연구)

  • Kim, Seonchil;Lee, Sangyeol
    • Journal of The Korean Society of Integrative Medicine
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    • v.5 no.1
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    • pp.19-24
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    • 2017
  • Purpose : The purpose of this study was to find out the difference motion of hip, knee and ankle joint during walking according to using walker on older people. Method : Korean older people of 34 subjects was participated in this study. Participants was measured joint motion on hip, knee and ankle joint during both conditions (walking with walker and without walker). The measured data were analyzed using independent t-test to investigate the difference of joint motion on the both condition. The statistical analyses were performed using Predictive Analytics Soft Ware (PASW) for windows(Ver. 19) and p-value less than .05 were considered significant for all cases. Result : The study showed that more joint motion on hip flexion and ankle pronation is increased by using walker. And hip extension, knee external rotation and ankle plantar flexion is decreased by using walker. Conclusion : This study suggest that using walker on older people was change the motion of the lower limb joint during walking. Therefore, It is necessary to develop a new walker that can reduce dependency and ensure stability on older people during walking.