• 제목/요약/키워드: non-symmetry

검색결과 162건 처리시간 0.022초

Software development for the visualization of brain fiber tract by using 24-bit color coding in diffusion tensor image

  • Oh, Jung-Su;Song, In-Chan;Ik hwan Cho;Kim, Jong-Hyo;Chang, Kee-Hyun;Park, Kwang-Suk
    • 대한자기공명의과학회:학술대회논문집
    • /
    • 대한자기공명의과학회 2002년도 제7차 학술대회 초록집
    • /
    • pp.133-133
    • /
    • 2002
  • Purpose: The purpose of paper is to implement software to visualize brain fiber tract using a 24-bit color coding scheme and to test its feasibility. Materials and Methods: MR imaging was performed on GE 1.5 T Signa scanner. For diffusion tensor image, we used a single shot spin-echo EPI sequence with 7 non-colinear pulsed-field gradient directions: (x, y, z):(1,1,0),(-1,1,0),(1,0,1),(-1,0,1),(0,1,1),(0,1,-1) and without diffusion gradient. B-factor was 500 sec/$\textrm{mm}^2$. Acquisition parameters are as follows: TUTE=10000ms/99ms, FOV=240mm, matrix=128${\times}$128, slice thickness/gap=6mm/0mm, total slice number=30. Subjects consisted of 10 normal young volunteers (age:21∼26 yrs, 5 men, 5 women). All DTI images were smoothed with Gaussian kernel with the FWHM of 2 pixels. Color coding schemes for visualization of directional information was as follows. HSV(Hue, Saturation, Value) color system is appropriate for assigning RGB(Red, Green, and Blue) value for every different directions because of its volumetric directional expression. Each of HSV are assigned due to (r,$\theta$,${\Phi}$) in spherical coordinate. HSV calculated by this way can be transformed into RGB color system by general HSV to RGB conversion formula. Symmetry schemes: It is natural to code the antipodal direction to be same color(antipodal symmetry). So even with no symmetry scheme, the antipodal symmetry must be included. With no symmetry scheme, we can assign every different colors for every different orientation.(H =${\Phi}$, S=2$\theta$/$\pi$, V=λw, where λw is anisotropy). But that may assign very discontinuous color even between adjacent yokels. On the other hand, Full symmetry or absolute value scheme includes symmetry for 180$^{\circ}$ rotation about xy-plane of color coordinate (rotational symmetry) and for both hemisphere (mirror symmetry). In absolute value scheme, each of RGB value can be expressed as follows. R=λw|Vx|, G=λw|Vy|, B=λw|Vz|, where (Vx, Vy, Vz) is eigenvector corresponding to the largest eigenvalue of diffusion tensor. With applying full symmetry or absolute value scheme, we can get more continuous color coding at the expense of coding same color for symmetric direction. For better visualization of fiber tract directions, Gamma and brightness correction had done. All of these implementations were done on the IDL 5.4 platform.

  • PDF

Analysis of instrument exercise using IMU about symmetry

  • Yohan Song;Hyun-Bin Zi;Jihyeon Kim;Hyangshin Ryu;Jaehyo Kim
    • International Journal of Advanced Culture Technology
    • /
    • 제11권1호
    • /
    • pp.296-305
    • /
    • 2023
  • The purpose of this study is to measure and compare the balance of motion between the left and right using a wearable sensor during upper limb exercise using an exercise equipment. Eight participants were asked to perform upper limb exercise using exercise equipment, and exercise data were measured through IMU sensors attached to both wrists. As a result of the PCA test, Euler Yaw(Left: 0.65, Right: 0.75), Roll(Left: 0.72, Right: 0.58), and Gyro X(Left: 0.64, Right: 0.63) were identified as the main components in the Butterfly exercise, and Euler Pitch(Left: 0.70, Right 0.70) and Gyro Z(Left: 0.70, Right: 0.71) were identified as the main components in the Lat pull down exercise. As a result of the Paired-T test of the Euler value, Yaw's Peak to Peak at Butterfly exercise and Roll's Mean, Yaw's Mean and Period at Lat pull down exercise were smaller than the significance level of 0.05, proving meaningful difference was found. In the Symmetry Index and Symmetry Ratio analysis, 89% of the subjects showed a tendency of dominant limb maintaining relatively higher angular movement performance then non-dominant limb as the Butterfly exercise proceeds. 62.5% of the subjects showed the same tendency during the Lat pull down exercise. These experimental results indicate that meaningful difference at balance of motion was found according to an increase in number of exercise trials.

리듬청각자극이 만성 뇌졸중 환자의 보행대칭성에 미치는 효과 (The Effects of Rhythmic Auditory Stimulation on the Gait Symmetry in the Chronic Stroke Patients)

  • 이순현;이경진;하귀현;인태성;송창호
    • 한국산학기술학회논문지
    • /
    • 제12권5호
    • /
    • pp.2187-2196
    • /
    • 2011
  • 본 연구는 리듬청각자극을 이용한 보행훈련이 뇌졸중 환자의 보행의 대칭성에 미치는 효과를 알아보고자 하였다. 6개월이 지난 만성 뇌졸중환자 40명을 대상으로 중재 방법에 따라 4군으로 나누었다. A군은 편안한속도로 마비측에 청각자극을 주고 B군은 편안한속도로 비마비측에 청각자극을 주고 C군은 10%증가된 속도로 마비측에 청각자극을 주고 D군은 10%증가시킨 속도로 비마비측에 청각자극을 주었다. 각 군의 환자에게 5분동안 청각자극을 주며 보행훈련을 시행하였다. 보행분석 시스템을 이용하여 보행의 시간적인 변수를 측정하였으며 계산공식을 이용하여 보행의 대칭성을 구하였다. 보시간은 A군을 제외한 모든 군에서 유의하게 감소하였고(p<.05), 보행대칭성도 A군을 제외한 모든 군에서 유의하게 개선되었다(p<.05). 분속수는 A군을 제외한 모든 군에서 유의하게 증가하였고(p<.05), 속도는 모든 군에서 증가하지 않았다. 이 결과를 통해 리듬청각자극이 보행의 대칭성을 개선하는데 효과적임을 확인하였으며 뇌졸중 환자의 보행훈련에 효과적인 방법으로 적용할 수 있으리라 생각한다.

NON-GEOMETRICAL CONSTANTS OF THE MOTION FOR THE MAXIMALLY SYMMETRIC SPACETIMES

  • DEHGHANI M. H.
    • 천문학회지
    • /
    • 제29권spc1호
    • /
    • pp.285-286
    • /
    • 1996
  • A systematric method of exploring the 'geometrical' and 'non-geometrical' constants of the motion for an arbitrary spacetime is presented. This is done by introducing a series of coupled differential equation for the generators of the symmetry group of Vlasov's equation. The method is applied to the case of the maximaly symmetric spectime, and the geometrical and non-geometrical constants of motion are obtained.

  • PDF

The Influence of Auditory-Feedback Device Using Wearable Air-Pressure Insole on Spatiotemporal Gait Symmetry in Chronic Hemplegia

  • Heo, Ji-Hun;Song, Changho;Jung, Sangwoo
    • Physical Therapy Rehabilitation Science
    • /
    • 제10권3호
    • /
    • pp.311-319
    • /
    • 2021
  • Objective: To investigate the effect of emphasized initial contact by using a wearable air-pressure insole to provide auditory-feedback with variations of maximum peak pressure (MPP) of the affected side on spatiotemporal gait parameters and gait symmetry of stroke patients Design: A cross-sectional study Methods: Eighteen stroke patients participated in this study. All subjects walked five trials using an air-pressure insole that provides auditory feedback with different thresholds set on the insole. First, subjects walked without any auditory feedback. Then, the MPP threshold on the affected side was set from 70% and increase threshold by 10% after each trial until 100%. They walked three times or more on the gait analyzer for each trial, and the average values were measured. Before starting the experiment, subjects measured body weight, initial gait abilities and affected side MPP without auditory feedback. Results: Temporal and spatial variables were significantly increased in trials with auditory feedback from air-pressure insole except for non-paralyzed single support time and spatial gait symmetry compared to trials without auditory feedback(p<0.05). Among the four different thresholds, the walking speed, unaffected side single support time, affected and unaffected side stride, and affected side step length were greatest at 80% threshold of maximum peak, while affected single support time, temporal gait symmetry, and unaffected step length were greatest at the maximum peak of 100% threshold. Conclusions: These results indicate that auditory feedback gait using air-pressure insoles can be an effective way to improve walking speed, single support time, step length, stride, and temporal gait symmetry in stroke patients.

들기 작업할 때 자세의 변화에 따른 악력과 지면 반발력의 상관관계 (The Relationship between Grip Strength and Ground Reaction Force by Change of Position when Lifting Tasks)

  • 정상용;강진우;구정완
    • 대한인간공학회지
    • /
    • 제28권3호
    • /
    • pp.41-47
    • /
    • 2009
  • The purpose of this study, during the lifting task was researching the difference and a relationship between the ground reaction force and the grip strength by change of position. After grip strength has measured in symmetry position and asymmetry position at 45cm and 75cm of height of hand, ground reaction force was measured by same attitude lifting wooden box. We analyzed the difference of grip strength and ground reaction force in each position change. The results of grip strength, the grip strength of both hand were significant difference that in study subject symmetry and asymmetry position (p<0.01). The results of symmetry lifting task, the study subjects was significant difference of the ground reaction force difference by height (p<0.05). Asymmetry lifting task was significant difference of ground reaction force difference by direction of rotation was changed (p<0.01). The result of it will rotate with non-dominant hand side of lifting tasks from height 75cm where it easily maintains a balance possibility and decreasing the load of the hand. Therefore, from the workshop in the work people, it will be between the height 75cm and non-dominant hand side of trunk rotatory direction in the lifting tasks. Future study is necessary researched about the change of grip strength when the height of the hand is higher, and the difference of the ground reaction force when the change of weight.

비대칭 "ㄱ" 단면 앵글제품의 압출굽힘 가공에 관한 연구 (A Study on the Extru-Bending Process of the Angle Product with non-Symmetric "ㄱ" Section)

  • 이경국;진인태
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2003년도 추계학술대회논문집
    • /
    • pp.277-280
    • /
    • 2003
  • It was investigated that the "ㄱ" type angle product could be bended with a curvature during extrusion by extru-bending process. The bending process for the "ㄱ" type angle product can be developed by the hot metal extru-bending machine with the two punches moving in the different velocity. Because of non-symmetry of product, it is important to design the ruled surface contour of dies cavity for the welding and bending with two billets. So it is designed that the multi-hole container has two non-symmetric holes and non-symmetric contour of dies entrance. The results of the experiment show that "ㄱ" type angle product can be bended by the extrusion process and that the curvature of the product can be controlled by the velocity of punch and that the defects such as the distortion of section and the thickness change of the product and the folding and wrinkling of the product did not happen after the bending processing by the extrusion bending machine.

  • PDF

그리스 스타일의 미적 특성 (Aesthetic Characteristics of Grecian Style)

  • 함연자
    • 한국의류산업학회지
    • /
    • 제9권6호
    • /
    • pp.595-602
    • /
    • 2007
  • This study examined the aesthetic characteristics of Grecian style which is being considered as the representative classic of Western fashion and the transformations of those Grecian styles on the fashion of the twentieth century. This study used positive research method using literatures on art history and clothing history, fashion related publications, and magazines and websites to understand the trend of fashion designer's collections. The study results are as follows. The aesthetic characteristics of Grecian style was considered to be the ideal beauty combined with symmetry, the functional beauty combined with non-construction, and the sensual beauty combined with natural body. The ideal beauty combined with symmetry appears as a style that shows idealistic proportion of a body emphasizing high-waist based on the golden ratio and the body as a whole rather than details. The functional beauty combined with non-construction appears as perfect recreation a body in its original and natural form. The clothing takes a form that does not have any structural design and has simplified cutting and sewing. It uses pins and strings to fix up the form of clothing which is flexible and naturally draped. The sensual beauty combined with natural body is found in natural silhouette dress alluding naked body in connection with Rousseau' naturalism in neoclassic period. Throughout the twentieth century, the desire for Grecian style was conveyed by a single detail or through an array of allusive effects.

문양 이미지에 관한 연구[ 1 ] -문양 이미지 포지셔닝 기준 개발을 중심으로- (A Study on Image of Patterns [ 1 ] - With a focus on Development on Image Positioning of Patterns -)

  • 유현정;김민자
    • 복식
    • /
    • 제59권2호
    • /
    • pp.29-41
    • /
    • 2009
  • Perception between real object and recognized subject of human on objective subject is not the same. The reason Is that individual perception of visual design components are transmitted as the image of whole. It is required process of visual perception. Therefore, I developed the vision of seeing image of pattern which is based on Gestalt visual perception theory in clothes. The summary of this study's results is like followings. Extremely antagonistic terms which are specialized by formative characteristics of formative components are clearness and blur of outline/ fixed shape and non-fixed shape/ visuality and tangibility of representation/ simplicity and complexity of structure/ invariability and variability of mobility/ symmetry and asymmetry of arrangements singularity and plurality of group number. The expression of motive shows that clearness, fixed shape, visuality and simplicity pursuit Determination image, and blur, non-fixed shape, tangibility and complexity pursuit Ambiguity image. The arrangements of motive shows that invariability, symmetry and singularity pursuit Order image, and variability asymmetry and plurality pursuit Disorder image. Therefore, the standard of the coordinator of Pattern image positioning is established as Determination and Ambiguity of motive are X-axis, and Order and Disorder of pattern are Y-axis. As the frame of Pattern image positioning, four separated dimensions have made.

관절오목 이형성이 있는 개의 내측 슬개골 탈구 수술 전, 후의 운동역학적 보상적 보행 변화 (증례보고) (Compensatory Change of a Dog with Glenoid Dysplasia in Kinetic Gait Analysis before and after Reconstruction of Medial Patellar Luxation (Case report))

  • 이신호;서정현;차유리
    • 대한물리치료과학회지
    • /
    • 제31권1호
    • /
    • pp.46-52
    • /
    • 2024
  • Background: This study aims to investigate compensatory strategy in a dog with glenoid dysplasia using kinetic gait analysis before and after reconstruction of medial patellar luxation. Design: Case report Method: On the platform, gait analysis was evaluated for a dog with congenital luxation and bilateral medial patellar luxation (MPL). A dog was evaluated for maximal vertical force (MVF), body load distribution (BLD), and symmetry index (SI), including the left forelimb with congenital luxation before MPL surgery, 15 days of surgery, and 40 days of surgery. Result:: In the comparison between the preoperative and the 15 days of surgery, the MVF of the bilateral forelimbs, especially in the non-affected forelimbs, increased, and the SI also increased. For BLD, the maximum load distribution increased, but the total load distribution decreased. In the comparison of 15 days and 40 days of surgery, MVF and BLD increased, and SI decreased on 40days of surgery. Conclusions: In a dog, the shift in weight load to the non-affected side occurs all the limbs, affecting the peak vertical force, weight load distribution, and symmetry index.