• 제목/요약/키워드: visual speed

검색결과 547건 처리시간 0.028초

DEEP-South: Performance of Moving Object Detection Program in Different Observation Modes

  • Oh, Young-Seok;Bae, Yeong-Ho;Kim, Myung-Jin;Roh, Dong-Goo;Jin, Ho;Moon, Hong-Kyu;Park, Jintae;Lee, Hee-Jae;Yim, Hong-Suh;Choi, Young-Jun
    • 천문학회보
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    • 제41권2호
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    • pp.48.3-49
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    • 2016
  • We have five different types of observation modes with regard to the Deep Ecliptic Patrol of the Southern Sky (DEEP-South); Opposition Census (OC) for targeted photometry, Sweet Spot Survey (S1) for discovery and orbit characterization of Atens and Atiras, Ecliptic Survey (S2) for asteroid family studies and comet census, NEOWISE follow-up (NW) for near simultaneous albedo measurements in the visible bands, and Target of Opportunity (TO) observation for follow-up either for unpredictable events or targets of special interests. Different exposures with such different modes result in a wide range of background noise level, the number of background stars and the mover's projected speed in each image. The Moving Object Detection Program (MODP) utilizes multiple mosaic images being taken for the same target fields at different epochs at the three KMTNet sites. MODP employs existing software packages such as SExtractor (Source-Extractor) and SCAMP (Software for Calibrating Astrometry and Photometry); SExtractor generates object catalogs, while SCAMP conducts precision astrometric calibration, then MODP determines if a point source is moving. This package creates animated stamp images for visual inspection with MPC reports, the latter for checking whether an object is known or unknown. We evaluate the astrometric accuracy and efficiency of MODP using the year one dataset obtained from DEEP-South operations.

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공을 이용한 안뜰계 훈련이 정상 성인의 정적 균형에 미치는 영향 (Effect of Vestibular Training Using Ball on Static Balance in Normal Subjects)

  • 최수희;조화영;강양훈;곽광일;권혜민;서삼기
    • 대한임상전기생리학회지
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    • 제9권2호
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    • pp.13-23
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    • 2011
  • Purpose : The purpose of this study is to investigate the effect on the static balance ability according to vestibular training using ball. Methods : Twenty normal subjects participated and were randomly assigned to either a vestibular training group using ball or a control group. The vestibular training using a ball group exercised 3 times per week over 3 weeks. The static balance was assessed by the center of pressure to the stance position. The participants stood barefoot on a force platform in a normal stance and a one-legged stance with a visual close. Results : In the normal stance, there were no significant differences at CoP surface and CoP speed. However, in a one-legged stance, there were significant differences in the vestibular training group between before and after the program. There was also a significant difference between the vestibular training group and the control group. Conclusion : Vestibular training using ball can be implemented as a therapeutic intervention to improve static balance ability in health adults.

드뷔시 필터를 이용한 고속 프레넬릿 변환의 구현 (Implementation of High-Speed Fresnelet Transform using Daubechies's Filter)

  • 서영호;이윤혁;김동욱
    • 한국정보통신학회논문지
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    • 제21권4호
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    • pp.820-828
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    • 2017
  • 차세대 영상 시스템인 디지털 홀로그램을 서비스하기 위해서는 다양한 측면에서 신호처리 기술이 필요하다. 우리가 주로 사용하는 2차원 및 3차원 자연 영상을 처리하는데 있어서 가장 많이 사용되는 영상처리 도구는 변환이다. 디지털 홀로그램의 특성은 자연 영상과 매우 다른 특성을 갖기 때문에 2차원 영상에서 사용되던 변환 도구들을 디지털 홀로그램에 적용하는 것은 효율성이 매우 낮다. 이를 극복하기 위해 프레넬릿 변환이 제안되었는데 본 논문에서는 웨이블릿 기저함수에 유니터리 프레넬 변환을 적용하고 드뷔시 필터를 이용하여 프레넬릿 변환을 유도하였다. 또한 프레넬릿 변환을 디바이스 및 커널 코드를 이용하여 구현하여 동작 성능을 향상시키도록 하였다. 모든 해상도에 대해 한 화소당 소요되는 평균 시간을 기준으로 살펴보았을 때 디바이스 코드를 이용하여 병렬화 연산을 수행하면 (9,7)필터의 경우에는 평균 242배, (5,3)필터의 경우에는 평균 30배의 성능향상을 가져온다는 것을 확인하였다.

광역상수도용 펌프의 규격 최적결정방법에 관한 연구 (A Study on the Pump System Design Optimization for Regional Water Supply Facilities)

  • 노형운;서상호;김경엽;김성원;김일수;박종문;박희경;박노석;이봉주;이정우;이영범;이영호;김상균
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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    • pp.159-164
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    • 2001
  • An extensive range of pumping facilities are employed in the regional water supply system in metropolitan areas, and optimization and the systematic combination of the pump facilities have direct bearing on the stability and economy of the water supply system concerned. These systems must be able to guarantee stability, efficiency and offer high reliability. Preparation of metropolitan area regional water supply system construction project must include a basic plan which takes into account the suitability of pumping facilities to be used, the environment in which facilities will be installed, man-power requirements and basic operational and management policies. This paper contains over-all analysis of the management of metropolitan area regional water supply systems and highlights the cause of Inefficiency and energy waste and puts forward a remedial plan of action. In addition, pump/motor specification programs were developed using Visual Basic to assist selection of the same.

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The Feasibility of Event-Related Functional Magnetic Resonance Imaging of Power Hand Grip Task for Studying the Motor System in Normal Volunteers; Comparison with Finger Tapping Task

  • Song, In-Chan;Chang, Kee-Hyun;Han, Moon-Hee
    • 대한자기공명의과학회:학술대회논문집
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    • 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
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    • pp.111-111
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    • 2001
  • 목적: To evaluate the feasibility of the event-related functional MR study using power grip studying the hand motor system 대상 및 방법: Event-related functional MRI was performed on a 1.5T MR unit in seven norm volunteers (man=7, right-handedness=2, left-handedness=5, mean age: 25 years). A single-shot GRE-EPI sequence (TR/TE/flip angle: 1000ms/40ms/90, FOV = 240 mm matrix= 64$\times$64, slice thickness/gap = 5mm/0mm, 7 true axial slices) was used for functiona MR images. A flow-sensitive conventional gradient echo sequence (TR/TE/flip angl 50ms/4ms/60) was used for high-resolution anatomical images. To minimize the gross hea motion, neck-holders (MJ-200, USA) were used. A series of MR images were obtained in axial planes covering motor areas. To exclude motion-corrupted images, all MR images wer surveyed in a movie procedure and evaluated using the estimation of center of mass of ima signal intensities. Power grip task consisted of the powerful grip of all right fingers and hand movement ta used very fast right finger tapping at a speed of 3 per 1 second. All tasks were visual-guid by LCD projector (SHARP, Japan). Two tasks consisted of 134 phases including 7 activatio and 8 rest periods. Active stimulations were performed during 2 seconds and rest period were 15 seconds and total scan time per one task was 2 min 14 sec. Statistical maps we obtained using cross-correlation method. Reference vector was time-shifted by 4 seconds an Gaussian convolution with a FWHM of 4 seconds was applied to it. The threshold in p val for the activation sites was set to be 0.001. All mapping procedures were peformed usin homemade program an IDL (Research Systems Inc., USA) platform. We evaluated the activation patterns of the motor system of power grip compared to hand movement in t event-related functional MRI.

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우성과 비우성 손에서의 운동학습으로 나타나는 뇌 활성도 차이: fMRI 사례 연구 (The Difference of Cortical Activation Pattern According to Motor Learning in Dominant and Non.dominant Hand: An fMRI Case Study)

  • 박지원;장성호
    • The Journal of Korean Physical Therapy
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    • 제21권1호
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    • pp.81-87
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    • 2009
  • Purpose: Human brain was lateralized to dominant or non-dominant hemisphere, and could be reorganized by the processing of the motor learning. We reported four cases which showed the changes of the cortical activation patterns resulting from two weeks of training with the serial reaction time task. Methods: Four right-handed healthy subjects were recruited, who was equally divided to two training conditions (right hand training or left hand training). They were assigned to train the serial reaction time task for two weeks, which should press the corresponding four colored buttons as fast as accurately as possible when visual stimulus was presented. Before and after two weeks of training, reaction time and function magnetic resonance image (fMRI) was acquired during the performance of the same serial reaction time task as the training. Results: The reaction time was significantly decreased in all of subjects after training. Our fMRI result showed that widespread bilateral activation at the pre scanning was shifted toward the focused activation on the contralateral hemisphere with progressive motor learning. However, the bilateral activation was still remained during the performance of the non-dominant hand. Conclusion: These findings showed that the repetitive practice of the serial reaction time task led to increase the movement speed and accuracy, as described by motor learning. Such motor learning induced to change the cortical activation pattern. And, the changed pattern of the cortical activation resulting from motor learning was different each other in accordance with the hand dominance.

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Low-dose CT Image Denoising Using Classification Densely Connected Residual Network

  • Ming, Jun;Yi, Benshun;Zhang, Yungang;Li, Huixin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권6호
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    • pp.2480-2496
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    • 2020
  • Considering that high-dose X-ray radiation during CT scans may bring potential risks to patients, in the medical imaging industry there has been increasing emphasis on low-dose CT. Due to complex statistical characteristics of noise found in low-dose CT images, many traditional methods are difficult to preserve structural details effectively while suppressing noise and artifacts. Inspired by the deep learning techniques, we propose a densely connected residual network (DCRN) for low-dose CT image noise cancelation, which combines the ideas of dense connection with residual learning. On one hand, dense connection maximizes information flow between layers in the network, which is beneficial to maintain structural details when denoising images. On the other hand, residual learning paired with batch normalization would allow for decreased training speed and better noise reduction performance in images. The experiments are performed on the 100 CT images selected from a public medical dataset-TCIA(The Cancer Imaging Archive). Compared with the other three competitive denoising algorithms, both subjective visual effect and objective evaluation indexes which include PSNR, RMSE, MAE and SSIM show that the proposed network can improve LDCT images quality more effectively while maintaining a low computational cost. In the objective evaluation indexes, the highest PSNR 33.67, RMSE 5.659, MAE 1.965 and SSIM 0.9434 are achieved by the proposed method. Especially for RMSE, compare with the best performing algorithm in the comparison algorithms, the proposed network increases it by 7 percentage points.

Human-Computer Interaction Based Only on Auditory and Visual Information

  • Sha, Hui;Agah, Arvin
    • Transactions on Control, Automation and Systems Engineering
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    • 제2권4호
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    • pp.285-297
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    • 2000
  • One of the research objectives in the area of multimedia human-computer interaction is the application of artificial intelligence and robotics technologies to the development of computer interfaces. This involves utilizing many forms of media, integrating speed input, natural language, graphics, hand pointing gestures, and other methods for interactive dialogues. Although current human-computer communication methods include computer keyboards, mice, and other traditional devices, the two basic ways by which people communicate with each other are voice and gesture. This paper reports on research focusing on the development of an intelligent multimedia interface system modeled based on the manner in which people communicate. This work explores the interaction between humans and computers based only on the processing of speech(Work uttered by the person) and processing of images(hand pointing gestures). The purpose of the interface is to control a pan/tilt camera to point it to a location specified by the user through utterance of words and pointing of the hand, The systems utilizes another stationary camera to capture images of the users hand and a microphone to capture the users words. Upon processing of the images and sounds, the systems responds by pointing the camera. Initially, the interface uses hand pointing to locate the general position which user is referring to and then the interface uses voice command provided by user to fine-the location, and change the zooming of the camera, if requested. The image of the location is captured by the pan/tilt camera and sent to a color TV monitor to be displayed. This type of system has applications in tele-conferencing and other rmote operations, where the system must respond to users command, in a manner similar to how the user would communicate with another person. The advantage of this approach is the elimination of the traditional input devices that the user must utilize in order to control a pan/tillt camera, replacing them with more "natural" means of interaction. A number of experiments were performed to evaluate the interface system with respect to its accuracy, efficiency, reliability, and limitation.

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각속도 및 광센서를 이용한 헤드 마우스 (Head Mouse System Based on A Gyro and Opto Sensors)

  • 박민제;유재하;김수찬
    • 전자공학회논문지SC
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    • 제46권4호
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    • pp.70-76
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    • 2009
  • 본 연구에서는 자동차 사고나 뇌졸중 둥에 의해 경추 이하의 마비나 손, 발 등의 움직임이 자유롭지 못한 사람들의 컴퓨터 사용을 돕고자 손이나 발을 이용하지 않고 머리의 움직임과 눈의 깜박임만으로 컴퓨터 마우스 제어가 가능한 장치를 제안하였다. 마우스의 위치는 각속도 센서를 이용하여 머리의 움직임으로 추정하고, 눈 깜빡임에 의한 클릭과 더블 클릭은 광센서의 시야를 방해하지 않는 위치에 장착하여 커 클위치와 이벤트를 검출하였다. 제안한 마우스의 공간 이동 능력과 이벤트 검출을 비교한 실험에서는 좌우, 상하 이동은 기존 마우스와 비교하여 속도 면에서는 큰 차이는 없었으나, 정확도가 조금 떨어지는 이유로 인하여 정확한 위치로 이동시키는데 소요시간이 3$\sim$4배 정도 더 필요하였다. 데드 존을 갖는 비선형 상대 좌표계 방식을 이용하여 주기적으로 적분 에러를 제거해야 하는 문제를 해결하였고, 이동 거리와 속도를 함께 고려하여 직관적인 마우스 포인터 제어가 가능하도록 하였다. 주변광의 영향을 최소화하도록 광원 제어 회로를 설계하여 외부 광원의 변화에도 마우스 이벤트 검출이 영향을 받지 않았다.

Relationships Between Cognitive Function and Gait-Related Dual-Task Interference After Stroke

  • Kim, Jeong-Soo;Jeon, Hye-Seon;Jeong, Yeon-Gyu
    • 한국전문물리치료학회지
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    • 제21권3호
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    • pp.80-88
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    • 2014
  • Previous studies have reported that decreased cognitive ability has been consistently associated with significant declines in performance of one or both tasks under a dual-task walking condition. This study examined the relationship between specific cognitive abilities and the dual-task costs (DTCs) of spatio-temporal gait parameters in stroke patients. The spatio-temporal gait parameters were measured among 30 stroke patients while walking with and without a cognitive task (Stroop Word-Color Task) at the study participant's preferred walking speed. Cognitive abilities were measured using Computerized Neuropsychological Testing. Pearson's correlation coefficients (r) were calculated to quantify the associations between the neuropsychological measures and the DTCs in the spatio-temporal gait parameters. Moderate to strong correlations were found between the Auditory Continuous Performance test (ACPT) and the DTCs of the Single Support Time of Non-paretic (r=.37), the Trail Making A (TMA) test and the DTCs of Velocity (r=.71), TMA test and the DTCs of the Step Length of Paretic (r=.37), TMA test and the DTCs of the Step Length Non-paretic (r=.36), the Trail Making B (TMB) test and the DTCs of Velocity (r=.70), the Stroop Word-Color test and the DTCs of Velocity (r=-.40), Visual-span Backward (V-span B) test and the DTCs of Velocity (r=-.41), V-span B test and the DTCs of the Double Support Time of Non-paretic (r=.38), Digit-span Forward test and the DTCs of the Step Time of Non-paretic (r=-.39), and Digit-span Backward test and the DTCs of the Single Support Time of Paretic (r=.36). Especially TMA test and TMB test were found to be more strongly correlated to the DTCs of gait velocity than the other correlations. Understanding these cognitive features will provide guidance for identifying dual- task walking ability.