• Title/Summary/Keyword: Visual Signal

Search Result 545, Processing Time 0.032 seconds

Challenges in neuro-machine interaction based active robotic rehabilitation of stroke patients

  • Song, Aiguo;Yang, Renhuan;Xu, Baoguo;Pan, Lizheng;Li, Huijun
    • Advances in robotics research
    • /
    • v.1 no.2
    • /
    • pp.155-169
    • /
    • 2014
  • Study results in the last decades show that amount and quality of physical exercises, then the active participation, and now the cognitive involvement of patient in rehabilitation training are known of crux to enhance recovery outcome of motor dysfunction patients after stroke. Rehabilitation robots mainly have been developing along this direction to satisfy requirements of recovery therapy, or focusing on one or more of the above three points. Therefore, neuro-machine interaction based active rehabilitation robot has been proposed for assisting paralyzed limb performing designed tasks, which utilizes motor related EEG, UCSDI (Ultrasound Current Source Density Imaging), EMG for rehabilitation robot control and feeds back the multi-sensory interaction information such as visual, auditory, force, haptic sensation to the patient simultaneously. This neuro-controlled and perceptual rehabilitation robot will bring great benefits to post-stroke patients. In order to develop such kind of robot, some key technologies such as noninvasive precise detection of neural signal and realistic sensation feedback need to be solved. There are still some grand challenges in solving the fundamental questions to develop and optimize such kind of neuro-machine interaction based active rehabilitation robot.

FPGA-based Hardware Prediction Rendering for Low-Latency Touch Platform

  • Song, Seok Bin;Kim, Jin Heon
    • Journal of Multimedia Information System
    • /
    • v.5 no.1
    • /
    • pp.59-62
    • /
    • 2018
  • The delay between input action and visual interface feedback ("Latency") in a touchscreen inking task reduces the user's performance. When the latency is less than 2.38ms, the user cannot perceive the latency in dragging task. This value is difficult to achieve on recent touchscreens and general purpose computers. So, methods of predicting touch points to reduce perceptible latency has been proposed. In general, touch points prediction is not perfect. When using point prediction, feedback of the predicted points is displayed on the screen, after a while, erased when the actual points are displayed. When this task is implemented by software, it causes additional latency to work to erase predicted points feedback. It therefore propose a platform for rendering point prediction feedback without additional latency by the FPGA. This platform transmits input points and HDMI signals rendering feedback of input points to the FPGA. The FPGA draws the feedback of points predicted based on the input points on the HDMI and displays the screen. Since hardware rendering changes the HDMI signal every frame, it does not require erasing work and rendering can be done within an early time regardless of the amount of rendering, so we will reduce the latency.

Improving the Base-Layer BER performance at AT-DMB using a Channel Estimation (AT-DMB 시스템에서 채널추정을 이용한 기본계층 수신 성능 향상기법)

  • Bang, Keuk-Joon
    • 전자공학회논문지 IE
    • /
    • v.49 no.2
    • /
    • pp.46-51
    • /
    • 2012
  • Transmit signal of Enhancement Layer in AT-DMB system is received by Coherent Detection, but in Base Layer of AT-DMB, a differential modulation and demodulation is adopted, same as the T-DMB. Especially for the coherent dectection of enhancement layer in AT-DMB system, a channel estimation must be employed. In this paper, I will show that the BER performance of Base-Layer in AT-DMB system will be improved by using the channel estimation information. The suggested method is focusing the constallations after Equalizaing to the nearlest ${\pi}$/4-shift DQPSK constallation points. Simulation results show that for the non-coding environment, the BER performance of AWGN channel, about 2-dB gain can be achieved at $10^{-4}BER$.

Frame Error Concealment Using Pixel Correlation in Overlapped Motion Compensation Regions

  • Duong, Dinh Trieu;Choi, Byeong-Doo;Hwang, Min-Cheol;Ko, Sung-Jea
    • ETRI Journal
    • /
    • v.31 no.1
    • /
    • pp.21-30
    • /
    • 2009
  • In low bit-rate video transmission, the payload of a single packet can often contain a whole coded frame due to the high compression ratio in both spatial and temporal domains of most modern video coders. Thus, the loss of a single packet not only causes the loss of a whole frame, but also produces error propagation into subsequent frames. In this paper, we propose a novel whole frame error concealment algorithm which reconstructs the first of the subsequent frames instead of the current lost frame to suppress the effects of error propagation. In the proposed algorithm, we impose a constraint which uses side match distortion (SMD) and overlapped region difference (ORD) to estimate motion vectors between the target reconstructed frame and its reference frame. SMD measures the spatial smoothness connection between a block and its neighboring blocks. ORD is defined as the difference between the correlated pixels which are predicted from one reference pixel. Experimental results show that the proposed algorithm effectively suppresses error propagation and significantly outperforms other conventional techniques in terms of both peak signal-to-noise ratio performance and subjective visual quality.

  • PDF

A Fine Granular Scalable Video Coding Algorithm using Frequency Weighting (주파수 특성을 이용한 미세 계위적 동영상 부호화 방법)

  • 김승환;호요성
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.40 no.6
    • /
    • pp.124-131
    • /
    • 2003
  • In this paper, we propose a Progressive scalable video coding algorithm using frequency weighting in the DCT domain. Since the human visual system (HVS) can be modeled as a nonlinear point transformation, called the modulation transfer function (MTF), we tan use the frequency weighting matrix to enhance the video image quality. We change this frequency weighting matrix into the frequency shift matrix to apply to the bit-plane coding method for the fine granular scalable (FGS) video coding We also define a new error metric JNDE (just noticeable difference) to measure the perceptual image quality in terms of human vision.

Intracranial Plasma Cell Granuloma

  • Kim, Dae-Jin;Choi, Yu-Seok;Song, Young-Jin;Kim, Ki-Uk
    • Journal of Korean Neurosurgical Society
    • /
    • v.46 no.2
    • /
    • pp.161-164
    • /
    • 2009
  • Plasma cell granuloma is a tumor-like disease characterized by non-neoplastic polyclonal proliferation of plasma cells and other mononuclear cells. This disease occurs most frequently in the lung and upper respiratory tract, while the involvement of the central nervous system is very rare. A 44-year-old female patient presented with nausea and progressive visual disturbance. Brain magnetic resonance imaging (MRI) revealed the mass along the right tentorium with low signal intensity in the T2 weighted image (T2WI) and fluid-attenuated inversion recovery (FLAIR) sequence, and an isosignal intensity in T1 weighted image (T1WI), the latter of which was enhanced after administration of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA). The thickest portion of the tentorium was partially excised via the combined suboccipital and infratentorial approach. The histopathological examination indicated a diagnosis of plasma cell granuloma. Postoperative steroid therapy was administered for remnant tumor control. Although a follow up MRI scan taken 20 months after the operation showed a slight decrease in tumor size, the lesion had extended to the falx and left frontal convexity along with parenchymal edema at 32 months after the operation and the clinical status was aggravated. The mass was removed from the left frontal convexity. Radiation therapy was given, together with steroid administration.

Measurement of Blood Oxygen Saturation System and LavVIEW Program Using Broad-band Light Source (광대역 광원을 이용한 혈중 산소포화도의 측정 시스템 및 랩뷰 프로그램)

  • Cui, Jin Shi;Shin, Dong Ho;Song, Chul Gyu
    • Journal of Korea Multimedia Society
    • /
    • v.18 no.2
    • /
    • pp.128-137
    • /
    • 2015
  • Blood oxygen saturation ($SpO_2$) is so important to be called bio-signal of the fifth. The measurement of blood oxygen saturation based on broad-ban light source has advantages of simple testing facility and easy understanding. This paper proposes a LabVIEW program which measures blood oxygen saturation based on broad-band light source. It combines LabVIEW and MATLAB, utilizing different light absorptions of oxyhemoglobin and deoxyhemoglobin in the visual wavelength range of 450nm-750nm to determine blood oxygen saturation. In order to improve accuracy through reducing the impact of hand shaking, the probe is fixed to the motor stage and then move a constant distance between the probe and the sample to be measured. Experimental results show that the proposed method noticeably increases the accuracy and saves time compared with the conventional methods.

Implementation of the Function Block Builder for the Distributed Control System (분산 제어 시스템용 기능 블록 작성기 구현)

  • 권만준
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.6 no.6
    • /
    • pp.974-979
    • /
    • 2002
  • There are so many kind of a control program that is applied in various process fields such as power generation plant, water treatment plant, incinerator plant, chemical plant, cement plant etc.. Because an engineer in field edits and changes and debugs and tests properly control programs using text-based control language, it is very hard for the him to apply to plant. Therefore, this research implemented a graphical tool for control program builder that is applicable to various plants and usable engineers having a little knowledge for control language. I wish to run more efficiently precision process control offering function that can see visual expression about flow of control signal and intermediate output values of control program displayed in screen using this implemented function block builder.

A Case of Cerebral Vasculitis in Henoch-Shönlein Purpura (알레르기성 자반증에 병발한 대뇌 혈관염 1례)

  • Lee, Soo Yeon;Choung, Ju Mi;Hwang, Dong Jin;Eun, So Hee;Hwang, Pyoung Han
    • Clinical and Experimental Pediatrics
    • /
    • v.45 no.12
    • /
    • pp.1601-1605
    • /
    • 2002
  • Henoch-Sh${\ddot{o}}$nlein Purpura(HSP) is an immuologically mediated systemic vasculitis of small blood vessels affecting predominantly the skin, gastrointestinal tract, joints, and kidneys. Clinical neurological manifestations such as headaches, behavioral changes, mental changes, seizures, and visual loss are described, but neurological complication are rare during the course of HSP. We experienced a case of an 8 year-old male with HSP who presented with seizures. Magnetic resonance imaging(MRI) showed multiple high signal intensity in both cortical and subcortical areas of frontal and parieto-occipital lobes and magnetic resonance(MR) angiogram showed stenosis of cerebral arteries, compatible with MRI and MR angiogram findings of cerebral vasculitis. We report this case with related literature.

Learning a Single Joint Perception-Action Coupling: A Pilot Study

  • Ryu, Young-Uk
    • The Journal of Korean Physical Therapy
    • /
    • v.22 no.6
    • /
    • pp.43-51
    • /
    • 2010
  • Purpose: This study examined the influence of visuomotor congruency on learning a relative phase relationship between a single joint movement and an external signal. Methods: Participants (N=5) were required to rhythmically coordinate elbow flexion-extension movements with a continuous sinusoidal wave (0.375 Hz) at a $90^{\circ}$ relative phase relationship. The congruent group was provided online feedback in which the elbow angle decreased (corresponding to elbow flexion) as the angle trajectory was movingup, and vice versa. The incongruent group was provided online feedback in which the elbow angle decreased as the angle trajectory was moving down, and vice versa. There were two practice sessions (day 1 and 2) and each session consisted of 6 trials per block (5 blocks per session). Retention tests were performed 24 hours after session 2, and only the external sinusoidal wave was provided. Repeated ANOVAs were used for statistical analysis. Results: During practice, the congruent group was significantly less variable than the incongruent group. Phase variability in the incongruent group did not significantly change across blocks, while variability decreased significantly in the congruent group. In retention, the congruent group produced the required $90^{\circ}$ relative phase pattern with significantly less phase variability than the incongruent group. Conclusions: Congruent visual feedback facilitates learning. Moreover, the deprivation of online feedback does not affect the congruent group but does affect the incongruent group in retention.