• 한국전문물리치료학회지
• /
• 제17권1호
• /
• pp.36-42
• /
• 2010

The aim of this study was to investigate effects of reaching distance on movement time and trunk kinematics in hemiplegic patients. Eight hemiplegic patients participated in this study. The independent variables were side (sound side vs. affected side) and target distance (70%, 90%, 110%, and 130% of upper limb). The dependent variables were movement time measured by pressure switch and trunk kinematics measured by motion analysis device. Two-way analysis of variance with repeated measures was used with Bonferroni post-hoc test. (1) There were significant main effects in side and reaching distance for movement time (p=.01, p=.02). Post-hoc test revealed that there was a significant difference between 110% and 130% of reaching distance (p=.01). (2) There was a significant main effect in side and reaching distance for trunk flexion (p=.01, p=.00). Post-hoc test revealed that there were significant differences in all pair-wise reaching distance comparison. (3) There was a significant side by target distance interaction for trunk rotation (p=.04). There was a significant main effect in target distance (p=.00). Post-hoc test revealed that there were significant differences between 70% and 110%, 70% and 130%, 90% and 110%, 90% and 130% of target distance. It was known that trunk flexion is used more than trunk rotation during reaching task in hemiplegic patients from the findings of this study. It is also recommended that reaching training is performed with limiting trunk movement within 90% of target distance whereas reaching training is performed incorporating with trunk movement beyond 90% of target distance in patients with hemiplegia.

• 인지과학
• /
• 제20권4호
• /
• pp.555-571
• /
• 2009

본 연구는 맥락 정보가 심적 회전에 미치는 영향을 검증하였다. 첫 번째 실험에서는 심적 회전 시 주변 정보가 목표 자극을 회전하는데 미치는 영향을 조사하였다. 목표 글자와 주변 글자의 각도를 변화시키거나 좌우 글자의 위치를 바꾸어가며 목표 글자가 거울상인지 아닌지를 판단하게 하였다. 목표 글자는 세 글자로 이루어진 단어에서 가운데 글자로 정의하였고, 나머지 글자를 주변 글자로 정의하였다. 실험 결과 주변 글자의 회전 각도가 증가할수록 반응 시간이 증가하였다. 또한 목표 글자와 주변 글자의 회전 각도가 비슷할 때 반응 속도가 더 빠르게 나타났으며, 이러한 효과는 비단어 조건인 경우보다 단어 조건일 때 더 크게 나타났다. 두 번째 실험에서는 연습 난이도가 심적 회전에 미치는 영향을 조사하였다. 그 결과 회전 각도에 따라서 반응 시간이 증가하긴 했지만, 연습 시행 난이도는 심적 회전시간에 영향을 미치지 않았다. 위와 같은 실험 결과는 심적 회전이 주변 맥락 정보에 의해서는 영향을 받지만 연습 난이도와 같은 사전 맥락 정보는 심적 회전에 영향을 미치지 않음을 시사한다.

• 대한방사선기술학회지:방사선기술과학
• /
• 제30권2호
• /
• pp.153-159
• /
• 2007

PACS의 도입에 발맞추어 시작된 digital 의료영상은 현재 방사선 진단 및 치료 영역에서 일반화되었으며 특히 진단영역에서는 눈부신 발전을 거듭하고 있다. 치료영역에서의 digital image 구현은 상대적으로 느린 성장과정을 거쳐 오늘에 이르고 있다. 본 논문은 이러한 analog에서 digital로 변화하는 흐름을 인식하여 정도관리(Quality Assurance) 업무 중 mechanical check 부분을 digital image base 업무로 대체하여 수행하고, 기존의 육면체 또는 사각형틀의 개념을 탈피한 구형(球形)의 Spherical mechanical check device(SMCD) 고안하여 그 실용성을 실험하였다. Source(target)에서 image detecter 간의 거리가 항상 일정하고, Spherical mechanical check device(SMCD)의 중심까지 거리가 일정하다면 어느 방향에서 SMCD를 exposure하더라도 그 크기는 항상 일정하게 영상으로 표현 될 것이다. 이를 위해 정확한 반구(半球)를 2개 정밀 제작하여 그것을 합쳤을 때 정원(正圓)의 구(球)가 되도록 하였다. 이를 이용하여 radiation field와 light field의 일치도, radiation field 크기의 정확도($(5{\times}5,\;10{\times}10,\;15{\times}15\;cm)$), Collimator field 크기의 정확도($5{\times}5,\;10{\times}10,\;15{\times}15\;cm$), Gantry rotation isocenter check, Collimator rotation isocenter check, Room laser accuracy check, Collimator rotation angle check와 Couch rotation angle check 등 기존의 mechanical check를 digital image를 이용하여 실행할 수 있었으며, 기존의 Flat 또는 정육면체 형태의 mechanical check device로는 쉽게 하기 힘든 non-coplanar field에 적용되는 Gantry와 Couch가 동시에 rotation되었을 때 그 isocenter의 일치도를 real time으로 확인할 수 있었다.

• 대한의용생체공학회:의공학회지
• /
• 제24권1호
• /
• pp.45-53
• /
• 2003

Based on the 4-compartmental pharmacokinetic model developed in PART1, target-controlled infusion(TCI) pump system was designed and evaluated. The TCI system consists of digital board including microcontroller and digital signal process(DSP), analog board, motor-driven actuator, user friendly interface, power management and controller. It provides two modes according to the drugs: plasma target concentration and effect target concentration. Anaesthetist controls the depth of anaesthesia for patients by adjusting the required concentration to maintain both plasma and effect site in drug concentration. The data estimated in DSP include infusion rate, initial load dose, and rotation number of motor encoder. During TCI operation, plasma concentration. effect site concentration, awaken concentration, context-sensitive decrement time and system error information are displayed in real time. Li-ion battery guarantees above 2 hours without power line failure. For high reliability of the system, two microprocessors were used to perform independent functions for both pharmacokinetic algorithm and motor control strategy.

• Journal of electromagnetic engineering and science
• /
• 제14권2호
• /
• pp.79-81
• /
• 2014

In B-scan data measured by a pulse-type monostatic borehole radar, target signatures are seriously obscured by two clutters that differ in orientation and intensity. The primary clutter appears as a nearly constant time delay, which is caused by internal ringing between antenna and transceiver in the radar system. The secondary clutter occurs as an oblique time delay due to the guided borehole wave along the logging cable of the radar antenna. This issue led us to perform adaptive filtering processing for orientation-based clutter removal. This letter describes adaptive filtering processing consisting of a combination of edge detection, data rotation, and eigenimage filtering. We show that the hyperbolic signatures of a dormant air-filled tunnel target can be more distinctly enhanced by applying the proposed approach to the B-scan data, which are measured in a well-suited test site for underground tunnel detection.

• 대한전기학회논문지
• /
• 제37권9호
• /
• pp.636-645
• /
• 1988

A new filter algorithm is suggested improving structurally the conventional extended Kalman filter of which the performance is dependent on the selection of the reference axes, by use of line-of-sight axes and gain rotation technique. The implementation method using microcomputer which implements tracking Kalman filter is introduced in terms of hardware and software. Then, through the simulation the performance of suggested filter is compared with that of conventional extended Kalman filter and the possibility of the real time tracking of moving target is investigated.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제10권11호
• /
• pp.5624-5638
• /
• 2016

A novel method based on Surf points is proposed to detect and lock-track single ground target in aerial videos. Videos captured by moving cameras contain complex motions, which bring difficulty in moving object detection. Our approach contains three parts: moving target template detection, search area estimation and target tracking. Global motion estimation and compensation are first made by grids-sampling Surf points selecting and matching. And then, the single ground target is detected by joint spatial-temporal information processing. The temporal process is made by calculating difference between compensated reference and current image and the spatial process is implementing morphological operations and adaptive binarization. The second part improves KALMAN filter with surf points scale information to predict target position and search area adaptively. Lastly, the local Surf points of target template are matched in this search region to realize target tracking. The long-term tracking is updated following target scaling, occlusion and large deformation. Experimental results show that the algorithm can correctly detect small moving target in dynamic scenes with complex motions. It is robust to vehicle dithering and target scale changing, rotation, especially partial occlusion or temporal complete occlusion. Comparing with traditional algorithms, our method enables real time operation, processing $520{\times}390$ frames at around 15fps.

• 한국전자파학회논문지
• /
• 제26권4호
• /
• pp.397-403
• /
• 2015

본 논문은 임펄스 초광대역 레이다를 이용한 ISAR 영상의 기하보정 방법에 대해 서술하였다. 임펄스 초광대역 레이다는 시간영역에서 신호처리를 하므로 다중 경로, 간섭 문제 등이 일어나지 않는 장점이 있다. 안테나와 대상체 사이의 송수신 신호를 평면파라고 가정하면, ISAR 기하 모델에서 회전축의 중심을 점표적을 이용하여 계산한다. 수신 데이터에서 합성을 수행하기 전, 점표적은 최대 점의 위치를 최소 자승법으로 근사하여 회전축의 중심을 알아낼 수 있다. 이 방법은 대조비가 더 뛰어난 영상을 얻을 수 있었고, 엔트로피도 가장 큰 값을 가질 수 있었다. 이러한 방법은 장비를 최초 작동하거나 주기적으로 사용되어서 회전축의 중심을 보상하여 영상 합성을 할 것이다. 의료나 보안 감시와 같은 고정된 기하를 가지는 영상화 장비에서 유용하게 사용될 것이다.

• 한국지구물리탐사학회:학술대회논문집
• /
• 한국지구물리탐사학회 2005년도 제7회 특별심포지움 논문집
• /
• pp.11-18
• /
• 2005

Filament inversion routines are highly effective for target definition whenever total-field DHTEM vectors can be obtained using three-component logging tools. However most cross-hole components contain significant noise related to sensor design and errors in observation of probe rotation. Standard stacking methods can be used to improve data quality but additional statistical methods based on cross-correlation and spatial averaging of orthogonal components may be required to ensure a consistent vector migration path. Apart from assisting with spatial averaging, multiple filaments generated for successive time-windows can provide additional imaging information relating to target geometry and current migration. New digital receiver systems provide additional time-windows to provide better tracking options necessary for high-resolution imaging of this type.

• 한국의학물리학회지:의학물리
• /
• 제25권4호
• /
• pp.288-297
• /
• 2014

Dynamic conformal arc therapy (DCAT) and flattening-filter-free (FFF) beams are commonly adopted for efficient conformal dose delivery in stereotactic body radiation therapy (SBRT). Off-axis geometry (OAG) may be necessary to obtain full gantry rotation without collision, which has been shown to be beneficial for peripheral targets using flattened beams. In this study dose distributions in OAG using FFF were evaluated and the effect of mechanical rotation induced uncertainty was investigated. For the lateral target, OAG evaluation, sphere targets (2, 4, and 6 cm diameter) were placed at three locations (central axis, 3 cm off-axis, and 6 cm off-axis) in a representative patient CT set. For each target, DCAT plans under the same objective were obtained for 6X, 6FFF, 10X, and 10FFF. The parameters used to evaluate the quality of the plans were homogeneity index (HI), conformality indices (CI), and beam on time (BOT). Next, the mechanical rotation induced uncertainty was evaluated using five SBRT patient plans that were randomly selected from a group of patients with laterally located tumors. For each of the five cases, a plan was generated using OAG and CAG with the same prescription and coverage. Each was replanned to account for one degree collimator/couch rotation errors during delivery. Prescription isodose coverage, CI, and lung dose were evaluated. HI and CI values for the lateral target, OAG evaluation were similar for flattened and unflattened beams; however, 6FFF provided slightly better values than 10FFF in OAG. For all plans the HI and CI were acceptable with the maximum difference between flattened and unflattend beams being 0.1. FFF beams showed better conformality than flattened beams for low doses and small targets. Variation due to rotational error for isodose coverage, CI, and lung dose was generally smaller for CAG compared to OAG, with some of these comparisons reaching statistical significance. However, the variations in dose distributions for either treatment technique were small and may not be clinically significant. FFF beams showed acceptable dose distributions in OAG. Although 10FFF provides more dramatic BOT reduction, it generally provides less favorable dosimetric indices compared to 6FFF in OAG. Mechanical uncertainty in collimator and couch rotation had an increased effect for OAG compared to CAG; however, the variations in dose distributions for either treatment technique were minimal.