• Title/Summary/Keyword: Picture Quality

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Air Quality Evaluation with Passive Samplers for Large Cities (Passive Sampler를 이용한 대도시의 대기질 평가)

  • Jeon, Eui-Chan;Kim, Shin-Do;Choi, Kum-Chan
    • Journal of Environmental Impact Assessment
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    • v.7 no.2
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    • pp.83-88
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    • 1998
  • Filter badge type sampler has not been widely used to evaluate air quality over large cities in Korea while it can be successfully used for multi-point sampling and analysis. We evaluated the passive sampler as a new tool to monitor air quality over large cities. We latticed Metropolitan Seoul into $2{\times}2Km$ to give 136 points. $NO_2$ concentrations were measured at all the points in the Spring and Summer of 1997. According to the passive sampler data, natural green zones generally recorded lower $NO_2$ concentrations than major streets and traffic congestion areas. Passive samplers with abundant 136 points gave more detailed picture of $NO_2$ distribution while auto-monitoring network did not clearly provide the characteristics of local land use. Also, passive samplers gave 15% higher values than auto-monitoring network. The correlation between the two values appears very high judging from the regression slope of 0.92 and correlation coefficient of 0.91. This study clearly demonstrates the effectiveness of the passive sampler as a tool to monitor air quality over large cities.

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Stereo Image Quality Assessment Using Visual Attention and Distortion Predictors

  • Hwang, Jae-Jeong;Wu, Hong Ren
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.9
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    • pp.1613-1631
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    • 2011
  • Several metrics have been reported in the literature to assess stereo image quality, mostly based on visual attention or human visual sensitivity based distortion prediction with the help of disparity information, which do not consider the combined aspects of human visual processing. In this paper, visual attention and depth assisted stereo image quality assessment model (VAD-SIQAM) is devised that consists of three main components, i.e., stereo attention predictor (SAP), depth variation (DV), and stereo distortion predictor (SDP). Visual attention is modeled based on entropy and inverse contrast to detect regions or objects of interest/attention. Depth variation is fused into the attention probability to account for the amount of changed depth in distorted stereo images. Finally, the stereo distortion predictor is designed by integrating distortion probability, which is based on low-level human visual system (HVS), responses into actual attention probabilities. The results show that regions of attention are detected among the visually significant distortions in the stereo image pair. Drawbacks of human visual sensitivity based picture quality metrics are alleviated by integrating visual attention and depth information. We also show that positive correlation with ground-truth attention and depth maps are increased by up to 0.949 and 0.936 in terms of the Pearson and the Spearman correlation coefficients, respectively.

Application and conversion system of MPEG2-TS to RTP (MPEG2-TS를 RTP로의 적용 및 변환 시스템)

  • Shin, Geuk-Jae;Kim, Ho-Kyom;Hong, Jin-Woo;Jung, Hoe-Kyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.4
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    • pp.839-844
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    • 2011
  • IPTV contents are based on MPEG2-TS(Moving Picture Expert Group-2 Transport Stream). The Created content is delivered to each home's Set-Top box through the Internet service network, which will be visible on television through the decoding process. The using and spending of content expanding were quite limited in the other existing lines' devices. For this end, provided methods are to convert MPEG2-TS to other format and then transmit it. These methods are causing not only an overload to the system but also its increasing the hardware resource requirements. In this paper, the MPEG2-TS of IPTV's content using RTP(Real time Transport Protocol) provided by the applicable variety of devices and environmental system, was designed and implemented. Through this paper, the existing MPEG2-TS is providing other devices for distribution and consumption that can give better content to the consumers which means that the QoS(Quality of Service) was enhanced. And, the increased consumption and use of content will help the IPTV business to get more development and activation.

Adaptive QP Selection using residual transform coefficients of block (블록의 잔여 변환 계수를 이용한 적응적인 QP 선택)

  • Jun, Hye-Min;Seo, Jeong-Hoon;Lee, Yung-Lyul
    • Journal of Broadcast Engineering
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    • v.14 no.2
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    • pp.219-227
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    • 2009
  • In H.264/AVC, if each block is quantized with a adaptive quantization parameter(QP) regardless of the characteristics of a block, it could be the deterioration of the picture quality. In this paper, an adaptive block-based QP selection method is proposed in order to improve picture quality by utilizing the bit amounts of the zigzag-scanned integer transform coefficients of the neighboring blocks and changing the QP value in the current block. The proposed method works in the same way as the encoder and decoder without transmitting the change of QP value to the decoder side. The experimental results show that the proposed method achieves a gain of about $0.1\sim0.3dB$ compared with H.264/AVC.

Adaptive Interpolation for Intra Frames in H.264 Using Interference Function (H.264 인트라 프레임에서 방해함수를 이용한 적응적 보간)

  • Park Mi-Seon;Yoo Jae-Myeong;Toan Nguyen Dinh;Kim Ji-Soo;Son Hwa-Jeong;Lee Guee-Sang
    • The Journal of the Korea Contents Association
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    • v.6 no.10
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    • pp.107-113
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    • 2006
  • Error Concealment method for Intra frames in H.264 reconstructs the lost block by computing weighted average value of the boundary pixels of the neighboring blocks; up, bottom, left and right blocks. However a simple average of pixel values of the neighboring blocks for Intra frames in H.264 leads to excessive blurring and degrades the picture quality severely. To solve this problem, in this paper we estimate the dominant edge of lost block using the pixel values of the neighboring blocks and reconstruct the pixel values by choosing adaptive interpolation between directional interpolation and weighted average interpolation considering the result value of the interference function based on statistics. Finally directional interpolation method improves by determining the dominant edge direction considering the relation of the dominent edge and the edges of neighboring blocks. Experiments show improvement of picture quality of about $0.5{\sim}2.0dB$ compared with the method of H.264.

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Hardware Configuration and Paradox Measurement for the Determination of Arrow Trajectory (화살의 이동궤적을 위한 하드웨어 구성 및 패러독스 측정)

  • Jeong, Yeong-Sang;Yu, Jung-Won;Lee, Han-Soo;Kim, Sung-Shin
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.3
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    • pp.459-464
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    • 2012
  • The point of impact, the shot group, and the flight traces depend on the combination of unique features which decide moving traces of the arrow (paradox of the archer, length of the arrow shaft, weight, angle of the feather, and spline of the arrow shaft). The more dense the impact points in the shot group and the earlier elimination of paradox of the archer, the higher assessment is given for the product. However, there is no way to objectively assess the efficiency and quality of the arrow, and there is no numeric data to be used as the basis for comparison with other products. Although capturing the images of flying arrow using a high-speed motion picture camera is possible, we are limited to observation from specific view angle only. Hence, the criteria for efficiency and quality assessment are mostly based on subjective opinions of experts or hunters, or review on consumers' remarks. In this paper, we propose a hardware composition that are based on three detection frames consisting of line lasers and photo diode arrays without the high-speed motion picture camera. Predicated on measured coordinates data, a nobel method for the archer's paradox measurement, a key parameter that determine the arrow's trajectory, and corresponding numerical analysis model is proposed.

A Study of Digitalizing Analog Gamma Camera Using Gamma-PF Board (Gamma-PF 보드를 이용한 아날로그 감마카메라의 디지털화 연구)

  • Kim, Hui-Jung;So, Su-Gil;Bong, Jeong-Gyun;Kim, Han-Myeong;Kim, Jang-Hwi;Ju, Gwan-Sik;Lee, Jong-Du
    • Journal of Biomedical Engineering Research
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    • v.19 no.4
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    • pp.351-360
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    • 1998
  • Digital gamma camera has many advantages over analog gamma camera. These include convenient quality control, easy calibration and operation, and possible image quantitation which results in improving diagnostic accuracies. The digital data can also be utilized for telemedicine and picture archiving and communication system. However, many hospitals still operate analog cameras and have difficult situation to replace them with digital cameras. We have studied a feasibility of digitalizing an analog gamma camera into a digital camera using Gamma-PF interface board. The physical characteristics that we have measured are spatial resolution, sensitivity, uniformity, and image contrast. The patient's data obtained for both analog and digital camera showed very similar image quality. The results suggest that it may be feasible to upgrade an analog camera into a digital gamma camera in clinical environments.

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Developing a Composite Quality Indicator to Assess The Quality of Care for US Medicare End-stage Renal Disease Patients (미국 Medicare 투석환자 치료의 질 지표 개발 : 4가지 주요 치료영역을 바탕으로)

  • Kang, Hye-Young
    • Quality Improvement in Health Care
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    • v.7 no.2
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    • pp.204-216
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    • 2000
  • Background : There has been a concern that the quality of care provided to end-stage renal disease (ESRD) patients in the United States may not be as good as recommended. This paper illustrates a composite measure to assess, the quality of care received by ESRD patients undergoing in-center hemodialysis by incorporating outcomes for 4 major treatment areas. The 4 treatment areas are: dialysis treatments, anemia control, nutritional management, and blood pressure control. Methods : The major data source for the study was the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Study Wave 1 (DMMS-1) d Sixteen categories of a composite quality indicator were constructed by combining 4 dichotomous variables (16=2*2*2*2). representing the optimal vs. less than optimal level of outcome for each of the 4 treatment outcome measure respectively. Optimal outcome level for each treatment area was defined based on the recommendation from the National Kidney Foundation: (a) delivered dialysis doses (Kt/V) ${\geq}$ 1.2; (b) hematocrit level ${\geq}$ 30%; (c) serum albumin concentration ${\geq}$ 3.8g/dl ; and (d) blood pressure of <140 / <90mmHg. The 16 quality indicator were ranked according to their relative quality weights, which were estimated from its association with the relative risk of survival, adjusting for patient's baseline severity and dialysis facility characteristics. Results : Out of the entire sample of 2,179 patients, only 229 (10%) meet th recommended outcome levels for all 4 treatment areas. Overall, the study patients were distributed evenly over the 16 quality indicators, indicating a great variation in the quality of ESRD care. It appears that the rank of the 16 quality-indicators is driven by serum albumin concentration, suggesting that serum albumin concentration may be the most powerful predictor of ESRD patient survival among the 4 outcome measures. Conclusion : The developed quality indicator has the advantage of describin a range of care for dialysis patients and thus providing a more complete picture of care as compared to previous studies that have focused on only single or few components of the ESRD care.

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Developing the Customer Quality Satisfaction Index Using Online Reviews: Case Study of TV (리뷰를 활용한 고객 품질 만족도 지수 개발 : TV 사례연구)

  • Jiye, Shin;Heesoo, Kim;Jaiho, Lee;Hyoungwoo, Jeon;Jeongsik, Ahn;Sunghoon, Hwang
    • Journal of Korean Society for Quality Management
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    • v.50 no.4
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    • pp.863-876
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    • 2022
  • Purpose: The purpose of this study is to propose the product quality satisfaction index based on multiple linear regression using customer reviews. Methods: The proposed framework is composed of four steps. First, we collect online reviews and divide it into insight phrases. The insight phrases are classified using product attribute dictionary and sentiment analysis is conducted. Second, the importance of attributes is calculated in consideration of both regression coefficient and frequency. Third, the positive rate is calculated concerning sentiment analysis result. Therefore, the quality satisfaction index is measured by the weighted sum of importance and positive rate in the last step. Results: We conduct a case study using 2-years(2020, 2021) of Samsung TV reviews to confirm the effectiveness of the proposed methodology. As a result, we found that Picture quality is the most crucial attribute in TV evaluation. The importance of Gaming and content has grown up as the positive rate has also increased. Therefore, the overall satisfaction of TV has increased in 2021 compared to 2020. Conclusion: The result of this study shows that the proposed index reveals the customer's mind efficiently and can be explained by the importance and positive rate of each attribute. By using the proposed index, companies are able to improve and the priority of improvement can be determined.

A study of the color De-interlacing ASIC Chip design adopted the improved interpolation Algorithm for improving the picture quality using color space converter. (ADI 보간 알고리듬을 적용한 Color Space Converter 칩 설계에 관한 연구)

  • 이치우;박노경;진현준;박상봉
    • Proceedings of the IEEK Conference
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    • 2001.06d
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    • pp.199-202
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    • 2001
  • A current TV-OUT format is quite different from that of HDTY or PC monitor in encoding techniques. In other words, a conventional analog TV uses interlaced display while HDTV or PC monitor uses Non-interlaced / Progressive-scanned display. In order to encode image signals coming from devices that takes interlaced display format for progressive scanned display, a hardware logic in which scanning and interpolation algorithms are implemented is necessary. The ELA (Edge-Based Line Average) algorithm have been widely used because it provided good characteristics. In this study, the ADI(Adaptive De-interlacing Interpolation) algorithm using to improve the algorithm which shows low quality in vertical edge detections and low efficiency of horizontal edge lines. With the De-interlacing ASIC chip that converts the interlaced Digital YUV to De-interlaced Digital RGB is designed. The VHDL is used for chip design.

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