• Title/Summary/Keyword: Video Quality

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New Decision Rules for UWB Synchronization (UWB 동기화를 위한 새로운 결정 법칙들)

  • Chong, Da-Hae;Lee, Young-Yoon;Ahn, Sang-Ho;Lee, Eui-Hyoung;Yoo, Seung-Hwan;Yoon, Seok-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.2C
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    • pp.192-199
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    • 2008
  • In ultra-wideband (UWB) systems, conventionally, the synchronization is to align time phases of a locally generated template and any of multipath components to within an allowable range. However, the synchronization with a low-power multipath component could incur significant performance degradation in receiver operation (e.g., detection) after the synchronization. On the other hand, the synchronization with a high-power multipath component can improve the performance in receiver operation after the synchronization. Generally, the first one among multipath components has the largest power. Thus, the synchronization with the first path component can make better performance than that with low-power component in receiver operation after the synchronization, Based on which, we first propose an optimal decision rule based on a maximum likelihood (ML) approach, and then, develope a simpler suboptimal decision rule for selecting the first path component. Simulation results show that the system has good demodulation performance, which uses new synchronization definition and the proposed decision rules have better performance than that of the conventional decision rule in UWB multipath channels. Between macroblocks in the previous and the current frame. On video samples with high motion and scene change cases, experimental results show that (1) the proposed algorithm adapts the encoded bitstream to limited channel capacity, while existing algorithms abruptly excess the limit bit rate; (2) the proposed algorithm improves picture quality with $0.4{\sim}0.9$dB in average.

A Study on Motion Estimator Design Using DCT DC Value (DCT 직류 값을 이용한 움직임 추정기 설계에 관한 연구)

  • Lee, Gwon-Cheol;Park, Jong-Jin;Jo, Won-Gyeong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.3
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    • pp.258-268
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    • 2001
  • The compression method is necessarily used to send the high quality moving picture that contains a number of data in image processing. In the field of moving picture compression method, the motion estimation algorithm is used to reduce the temporal redundancy. Block matching algorithm to be usually used is distinguished partial search algorithm with full search algorithm. Full search algorithm be used in this paper is the method to compare the reference block with entire block in the search window. It is very efficient and has simple data flow and control circuit. But the bigger the search window, the larger hardware size, because large computational operation is needed. In this paper, we design the full search block matching motion estimator. Using the DCT DC values, we decide luminance. And we apply 3 bit compare-selector using bit plane to I(Intra coded) picture, not using 8 bit luminance signals. Also it is suggested that use the same selective bit for the P(Predicted coded) and B(Bidirectional coded) picture. We compare based full search method with PSNR(Peak Signal to Noise Ratio) for C language modeling. Its condition is the reference block 8$\times$8, the search window 24$\times$24 and 352$\times$288 gray scale standard video images. The result has small difference that we cannot see. And we design the suggested motion estimator that hardware size is proved to reduce 38.3% for structure I and 30.7% for structure II. The memory is proved to reduce 31.3% for structure I and II.

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Chromosome Analysis in Clinical Samples by Chromosome Diagnostic System Using Fluorescence in Situ Hybridization (국산 Fluorescence in Situ Hybridization 시스템을 이용한 다양한 검체에서의 염색체 분석)

  • Moon, Shin-Yong;Pang, Myung-Geol;Oh, Sun-Kyung;Ryu, Buom-Yong;Hwang, Do-Yeong;Jung, Byeong-Jun;Choe, Jin;Sohn, Cherl;Chang, Jun-Keun;Kim, Jong-Won;Kim, Seok-Hyun;Choi, Young-Min
    • Clinical and Experimental Reproductive Medicine
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    • v.24 no.3
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    • pp.335-340
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    • 1997
  • Fluorescence in situ hybridization (FISH) techniques allow the enumeration of chromosome abnormalities and from a great potential for many clinical applications. In order to produce quantitative and reproducible results, expensive tools such as a cooled CCD camera and a computer software are required. We have developed a Chromosome Image Processing System (Chips) using FISH that allows the detection and mapping of the genetic aberrations. The aim of our study, therefore, is to evaluate the capabilities of our original system using a black-and-white video camera. As a model system, three repetitive DNA probes (D18Z1, DXZ1, and DYZ3) were hybridized to variety different clinical samples such as human metaphase spreads and interphase nuclei obtained from uncultured peripheral blood lymphocytes, uncultured amniocytes, and germ cells. The visualization of the FISH signals was performed using our system for image acquisition and pseudocoloring. FISH images were obtained by combining images from each of probes and DAPI counterstain captured separately. Using our original system, the aberrations of single or multiple chromosomes in a single hybridization experiment using chromosomes and interphase nuclei from a variety of cell types, including lymphocytes, amniocytes, sperm, and biopsied blastomeres, were enabled to evaluate. There were no differences in the image quality in accordance with FISH method, fluorochrome types, or different clinical samples. Always bright signals were detected using our system. Our system also yielded constant results. Our Chips would permit a level of performance of FISH analysis on metaphase chromosomes and interphase nuclei with unparalleled capabilities. Thus, it would be useful for clinical purposes.

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A Prediction Search Algorithm by using Temporal and Spatial Motion Information from the Previous Frame (이전 프레임의 시공간 모션 정보에 의한 예측 탐색 알고리즘)

  • Kwak, Sung-Keun;Wee, Young-Cheul;Kimn, Ha-Jine
    • Journal of the Korea Computer Graphics Society
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    • v.9 no.3
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    • pp.23-29
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    • 2003
  • There is the temporal correlation of the video sequence between the motion vector of current block and the motion vector of the previous block. If we can obtain useful and enough information from the motion vector of the same coordinate block of the previous frame, the total number of search points used to find the motion vector of the current block may be reduced significantly. In this paper, we propose the block-matching motion estimation using an adaptive initial search point by the predicted motion information from the same block of the previous frame. And the first search point of the proposed algorithm is moved an initial point on the location of being possibility and the searching process after moving the first search point is processed according to the fast search pattern. Simulation results show that PSNR(Peak-to-Signal Noise Ratio) values are improved UP to the 1.05dB as depend on the image sequences and improved about 0.33~0.37dB on an average. Search times are reduced about 29~97% than the other fast search algorithms. Simulation results also show that the performance of the proposed scheme gives better subjective picture quality than the other fast search algorithms and is closer to that of the FS(Full Search) algorithm.

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A Study on the Bandwidth Assignment Scheme for Video Data Using Dynamic Parameters in the Wireless ATM Networks (무선 ATM망에서 동적 변수를 이용한 비디오 데이터의 대역폭 할당방식에 대한 연구)

  • Jang, Dong-Hyeok;Kim, Seung-Hwan;Lee, Sun-Sook;Kwon, Oh-Seok
    • The KIPS Transactions:PartC
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    • v.9C no.1
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    • pp.73-78
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    • 2002
  • In WATM networks, in order to perform dynamic slot allocation required slots of mobile terminals are estimated based on DP (Dynamic Parameter) reflecting characteristics of traffic. In VBR (Variable Bit Rate) traffic, slot allocation is done at MT considering both time-dependent characteristics and QoS (Quality of Service) requirements. In this paper, DPs-buffer state information and buffer state change-are transmitted through in-band signaling. BS (Base Station) performs dynamic slot allocation considering traffic characteristics of each MT (Mobile Terminal), in other words, buffer state information informs the potentiality of 'buffer full state'to BS if MT buffer is over the specific threshold value and buffer state change notifies change in buffer state of incoming cells to MT. If buffer state information is equal to 'low (more than threshold)' and 'abrupt increase' it generates 'buffer full' state cell transmission delay or cell loss might occur. At this time BS should assign additional slots to MT, and then MT consumes cells in its buffer. In simulation, the proposed scheme shows better performance in cell delay and loss than EPSA (Estimation-Prorated Slot Assignment) in-band scheme.

A Study on the Educational Effectiveness of Chronic Diseases Among University Students (일부 대학생들의 성인건강 교육의 효과에 관한 연구)

  • Kang, Hee-Sook;Cho, Hyun
    • Journal of the Korean Society of School Health
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    • v.8 no.1
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    • pp.143-154
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    • 1995
  • Korea has been recently reducing the quality of life as well as rising medical cost because of the increase of chronic diseases. But we can prevent those chronic diseases through the improvement of environment or life style. We evaluated the educational effectiveness of chronic diseases(hypertention, diabetes, cancer, stroke and other chronic diseases) designed to increase the knowledge, attitude and practice of chronic diseases among university students. Between August 1994 and November 1994, we implemented chronic diseases prevention instruction in intervention students; unmatched control students were selected in same university. We conducted pre- and post-intervention surveys both intervention and control students with self-reported questionnaires(50 items). We assigned score(0-4 points) to items and conducted a analysis of covariance(ANCOVA) with sex, grade and economic status as the covariate, using the SAS PC computer statistical package. And we culculated odds ratio with safety scores between intervention and control students. The results of this study were followed. 1. In demographic characteristics of subjects both pre- and post intervention, we found no significant differences in intervention and control students at religion, father's education, mother's education, mother's occupation and type of residence(p>0.05), but we found significant differences at sex(p<0.001), grade(p<0.001) and economic status(p<0.05). 2. The sex, grade and economic status-adjusted mean prevention knowledge scores for diabetes and stroke increased from the pre- to post-survey in the intervention students(p<0.001), but control students did not increased(p>0.05). As odds ratios in knowledge were below 1, the knowledge of intervention students were higher than control students. 3. The attitudes for general adult health increased from the pre- to post-survey in the intervention students(p<0.05), but control students did not increased(p>0.05). As odds ratios in attitudes were approximately 1, we can not say effectiveness in intervention students 4. The pratices for cancer and stroke increased from the pre- to post-survey in both the intervention and control students(p<0.001). Also odds ratio of hypertention was 0.91, and that of stroke was 1.14. 5. Health related behaviors did not increased from the pre- to post- survey in both the intervention and control students(p>0.05). But odds ratio of drinking was 0.76 and that of body weight was 1.21. 6. Health status did not increased from the pre- to post- survey in both the intervention and control students(p>0.05). As odds ratio of health status was 1.09, prevention education was not effect in intervention students We would like to recommend as follows; 1. University students must learn about prevention of chronic diseases. Because the knowledge of invetervention students was higher than that of control students. 2. The prevention education of chronic diseases should be taught from primary school. 3. Adult health education for university students must be practiced continuously. Education period(l5 weeks) in this study was not complete. 4. The evaluation of chronic diseases was conducted real measurement(such as BP check) as well as self reported-survey. 5. Educational materials(video tape, pamphlet) related the prevention of chronic diseases should be developed at national level. And we must easely use those materials. 6. The prevention education of chronic diseases should be made through mass media as well as school education.

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A Scene Boundary Detection Scheme using Audio Information in MPEG System Stream (MPEG 시스템 스트림상에서 오디오 정보를 이용한 장면 경계 검출 방법)

  • Kim, Jae-Hong;Nang, Jong-Ho;Park, Soo-Yong
    • Journal of KIISE:Software and Applications
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    • v.27 no.8
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    • pp.864-876
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    • 2000
  • This paper proposes a new scene boundary detection scheme for the MPEG System stream using MPEG Audio information and proves its usefulness by extensive experiments. A scene boundary has a characteristic that the audio as well as video information are changed rapidly. This paper first classifies this scene boundary into three cases ; Radical, Gradual, Micro Changes, with respect to the audio changes. The Radical change has a large-scale changing of decibel value and pitch value at a scene boundary, the Gradual change shows the long-time transition of decibel and pitch values from max to min or vice versa, and the Micro change displays a some change of pitch or frequency distribution without decibel changes. Upon this analysis, a new scene change detection algorithm detecting these three cases is proposed in which a progressive window with a time line is used to trace the changes in the audio information. Some experiments with various movies show that proposed algorithm could produce a high detection ratio for Radical change that is the most popular scene change in the movies, while producing a moderate detection ratio for Gradual and Micro changes. The proposed scene boundary detection scheme could be used to build a database for visual information like MPEG System stream.

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The Verification of Korean Version Swallowing Disturbance Questionnaire (K-SDQ) (한국판 삼킴 곤란 척도(K-SDQ)의 번안본 검증)

  • Jung, SoWoon;Kim, JungWan
    • 재활복지
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    • v.22 no.4
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    • pp.43-58
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    • 2018
  • Swallowing disorders that can affect nutrient intakes and quality of life are commonly shown among the elderly as well as patients with neurogenic disorder. This study verifies the reliability and validity of the Swallowing Disturbance Questionnaire (SDQ), a subjective swallowing disability assessment tool, modified for Koreans' eating habit and cultural sentiment, against 105 stroke patients, in order to help identify early swallowing problems of the elderly. Reliability of internal consistency in the Korean version of SDQ is .601, test-retest reliability is .97, and concurrent validity is .956. Based on 8 points of cut-off score, 46.8% of sensitivity and 81.6% of specificity. Comparing the results of video fluoroscopic study (VFSS), an objective swallowing disorder test with those of Korean version of SDQ, negative predictive value (NPV) and positive predictive value (PPV) was shown as 81% and 53%. The Korean version of SDQ is expected to be a useful testing tool to discriminate swallowing disorders in stroke patients. It has great clinical significance in that swallowing difficulties shown by subjects can be sorted out to request a diagnostic assessment before clinical evaluation by a rehabilitation therapist or ruling out unnecessary exposure to additional tests by accurately identifying stroke patients without swallowing problems.

On the Legality of the Telemedicine between the Patient and Doctor Under the Medical Service Act - Focused on the Prescriptions to the Distanced Patients- (의사 환자 간 원격 의료의 의료법상 적법성에 관하여 - 원격 환자에 대한 처방 중심으로 -)

  • Kim, Jang Han
    • The Korean Society of Law and Medicine
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    • v.22 no.1
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    • pp.3-23
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    • 2021
  • Telemedicine is a field of medicine in which medicine doctors who are in remote distance can treat the patients using audio, video devices which can help the diagnosis. In medicine, even the face-to-face diagnosis and treatment is the traditional way, the telemedicine could provide the convenient way for the patients in long distance, disabled or anyone who want to be stay ones' home. But telemedicine has the task to maintain the quality of medical cares compare with the traditional medicine. Among the several types of telemedicine, the specific type telemedicine in which the medicine doctors examine, diagnosis and do the prescription to the remotely distanced patients could be defined tele-prescription. Under The Medical Service act, it is unclear that teleprescription could be allowed. The Medical Service Act has introduced the specific clause for the prescription. That clause includes the duty of patients who have to receive the prescriptions directly from medical doctors. Under this clause, the constitutional court had decided the tele-prescription was illegal, but the supreme court has been decided tele-prescription could be legalized under the certain circumstances. But the other supreme court decided the tele-prescription was illegal under the article 34 of presenting Medical Service Act. So to understand the interpretations of Supreme court and Constitutional court decisions for the cases of prescription via telephone, we need to understand the history and presented reasons for the revision of prescription clause and also need to understand the other related clauses in the same act. In conclusion, To consider the values of telemedicine should be the level with the ordinary treatments, It is reasonable to interpret that the presenting Medical Service Act only legalize the telemedicine between doctor to doctor and which is regulated by the telemedicine clause.

Analysis of Learners' Characteristics and Preferences for Effective Online Learning (효과적인 온라인 학습을 위한 학습자특성과 선호도 분석)

  • Lee, Young Lim;Im, Hee-Joo
    • Journal of Convergence for Information Technology
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    • v.11 no.12
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    • pp.138-147
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    • 2021
  • This study aims to analyze the characteristics and preferences of learners who participated in college online classes for effective online learning. A total of 101 college students who participated in online classes completed the survey including personal characteristics of students and learning factors that affect online classes. The results showed that male students were more likely than female students to respond that online classes were more effective. Likewise students who learned from video recordings compared to those who learned from real-time lectures. As a result of analyzing the difficulties of online learning, there was a high probability that online learning was ineffective for students who had difficulties in self-learning and asking questions to their lecturers. Likewise, students who spent a lot of time studying online lectures, there was a high probability that online classes would be more effective for students who spent a lot of time on assignments. The results suggest that online learning is more effective for students who learn actively and self-directedly than those who passively participate in classes. This study implies that it is necessary to design online classes based on the characteristics and preferences of learners to improve the quality of education.