• Title/Summary/Keyword: quality assessment.

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An Image Quality Assessment Scheme based on HVS using Gabor Function

  • Eom Minyoung;Choe Yoonsik
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.128-132
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    • 2004
  • In this paper, we propose a new image quality assessment scheme considering the human visual perception characteristics. A subjective quality assessment is obtained by the response of the receptive field in the primary visual cortex and a human's eye can't focus on all of the visual range in a moment. Take advantage of two facts above, we apply Gabor wavelet transform, which is well fit the receptive field in the cortex, to divided constant sized subblocks. Then a local distortion of the subblocks and a global distortion for the entire image are calculated in order. The proposed method has been evaluated using video test sequences provided by the Video Quality Experts Group (VQEG). The experimental results show that good correlation with human perception is obtained using the proposed metric, which is what we called GPSNR.

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Realtime No-Reference Quality-Assessment Over Packet Video Networks (패킷 비디오 네트워크상의 실시간 무기준법 동영상 화질 평가방법)

  • Sung, Duk-Gu;Kim, Yo-Han;Hana, Jung-Hyun;Shin, Ji-Tae
    • Journal of Broadcast Engineering
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    • v.14 no.4
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    • pp.387-396
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    • 2009
  • No-Reference video-quality assessments are divided into two kinds of metrics based on decoding pixel domain or the bitstream one. Traditional full-/reduced- reference methods have difficulty to be deployed as realtime video transmission because it has problems of additional data, complexity, and assessment accuracy. This paper presents simple and highly accurate no-reference video-quality assessment in realtime video transmission. Our proposed method uses quantization parameter, motion vector, and information of transmission error. To evaluate performance of the proposed algorithm, we perform subjective test of video quality with the ITU-T P.910 Absolute Category Rating(ACR) method and compare our proposed algorithm with the subjective quality assessment method. Experimental results show the proposed quality metric has a high correlation (85%) in terms of subjective quality assessment.

A Strategy on Performance Assessment Information System of Building Remodeling

  • Hong, Eun Hwa;Kim, Gyu Jin;Lee, Sang Chul;Lee, Jong Sik;Jo, Jae Ho;Chun, Jae Youl
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.643-645
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    • 2015
  • This study is designating the scope, in order to establish the information management system of performance assessment for remodeling buildings, to analyze the current status of performance assessment, and to identify technologies and concepts applicable to performance assessment model.

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A Method of Stereoscopic 3D Image Quality Assessment (스테레오스코픽 3D영상 화질 평가 방법)

  • Park, Young-Soo;Hur, Nam-Ho;Pyo, Kyung-Soo;Song, Chung-Kun
    • Journal of Broadcast Engineering
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    • v.16 no.2
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    • pp.319-330
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    • 2011
  • For objective assessment of stereoscopic 3D image quality, we measure quality of left and right image with 2D image quality measurement method. However, this method is inconvenient because that we have to measure quality of left and right image individually. Therefore we propose a method of stereoscopic 3D image quality assessment using one overlaid image with left and right image. Using this method, One can measure quality of stereoscopic 3D image more easily and quickly.

A Developmental Methodology of Environmental Impact Assessment: Application of Health Risk Assessment (환경영향평가에 있어서 건강위해성평가 기법의 활용방안에 관한 연구)

  • Koo, J.K.;Chung, Y.
    • Journal of Environmental Impact Assessment
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    • v.1 no.1
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    • pp.51-59
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    • 1992
  • Environmental Impact Assessment(EIA) is defined as an activity designed to identify and predict the impact on the environment. In the process of an EIA, the quantitative evaluation is generally performed for the air and water quality which have the national environmental quality standards. But the predicted values for the air and water quality are simply compared to the environmental standards. At present, the EIA process of Korea has no consideration for the possible human health risk resulting from the development projects. Environmental Health Impact Assessment(EHIA) is an applied methodology of EIA to estimate the acceptable health risk caused by a specified level of environmental pollutants. Estimating the excessive lifetime risk that is a possibility of dying of a certain disease by environmental contaminants, is useful as an evaluation technique of EHIA. It is recommanded the decision-makers to make efficient use of EHIA not only the development projects but also legislative proposals, policies and programmes in future.

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Developing system of forest habitat quality assessment for endangered species (멸종위기 야생생물 산림 서식지 질적 평가 체계 개발)

  • Kwang Bae Yoon;Sunryoung Kim;Seokwan Cheong;Jinhong Lee;Jae Hwa Tho;Seung Hyun Han
    • Korean Journal of Environmental Biology
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    • v.40 no.3
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    • pp.307-315
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    • 2022
  • In terms of habitat conservation, it is essential to develop a habitat assessment system that can evaluate not only the suitability of the current habitat, but also the health and stability of the habitat. This study aimed to develop a methodology of habitat quality assessment for endangered species by analyzing various existing habitat assessment methods. The habitat quality assessment consisted of selecting targeted species, planning of assessment, selecting targeted sites, assessing performance, calculating grade, and expert verification. Target sites were selected separately from core and potential habitats using a species distribution model or habitat suitability index. Habitat assessment factors were classified into ecological characteristic, landscape characteristic, and species-habitat characteristic. Ecological characteristic consisted of thirteen factors related to health of tree, vegetation, and soil. Landscape characteristic consisted of five factors related to fragment and connectivity of habitat. Species-habitat characteristic consisted of factors for evaluating habitat suitability depending on target species. Since meanings are different depending on characteristics, habitat quality assessment of this study could be used by classifying results for each characteristic according to various assessment purposes, such as designation of alternative habitats, assessment of restoration project, and protected area valuation for endangered species. Forest habitat quality assessment is expected to play an important role in conservation acts of endangered species in the future through continuous supplementation of this system in regard to quantitative assessment criteria and weighting for each factor with an influence.

A Study on the Comparative Analysis of UHD Video Quality from Audience Viewpoint (시청자 관점에서의 UHD 콘텐츠 화질 비교 분석에 관한 연구)

  • Cho, Yong Suk;Min, Dong Chul;Choi, Seong Jhin
    • Journal of Broadcast Engineering
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    • v.26 no.5
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    • pp.621-642
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    • 2021
  • In this paper, the subjective video quality assessment of the content quality was to examine by the assessors about the three content quality of HD, Up-scaling UHD, 4K UHD Native that is currently broadcasted. The comparative assessment was conducted using three types of TV sets, 55, 65, 75 inches, at a distance of 2.5 meters which is the distance of watching TV in general households. Among the participants who took part in the video quality evaluating experiment and the questionnaire survey, the answering data of the final 169 persons were adopted after removing the data of 4 persons who answered inadequately in the evaluation of the video quality. The effects of gender, preference of program genre, size of TV sets were analyzed statistically using SPSS 25.0 analysis package. In addition to these, the objective video quality assessment through the measuring instrument was performed, and compared with the results of subjective video quality assessment.

Analysis of Image Quality Based on Perceptual Vision

  • Xue, Liqin;Hua, Yuning;Qi, Yaping
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1494-1496
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    • 2007
  • This paper deals with image quality analysis considering the impact of psychological factors involved in assessment. The attributes of image quality requirement were partitioned according to the visual perception characteristics and the preference of image quality were obtained by the factor analysis method. The features of image quality which support the subjective preference were identified, The adequacy of image is evidenced to be the top requirement issues to the display image quality improvement.

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Health Insurance Benefit Criteria and Quality Assurance Policies of Diagnostic Ultrasound Services in Other Countries (주요국의 초음파검사 시행현황과 질 확보방안)

  • Chung, Seol Hee;Lee, Hye Jin;Kim, Han Sang;Oh, Ju-Yeon
    • Health Policy and Management
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    • v.24 no.2
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    • pp.109-119
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    • 2014
  • In accordance with the government's plan to expand the national health insurance (NHI) coverage for severe diseases such as cancer, heart disease, cerebrovascular disease, and rare and incurable disease, the diagnostic ultrasound services have been covered by NHI from October 1, 2013. The quality is very important factor in providing diagnostic services because they influence on the diagnosis, treatment, and outcome of diseases. In particular, equipments and health care providers plays an important role in providing qualitative services. The purpose of this paper is to examine the major feature of ultrasound services covered by health security system and to review quality assurance policies in other countries such as Australia, Japan, the USA, and Canada. In addition, we assessed the implication of those policies. We especially put emphasis on the types and qualifications of healthcare professionals and measures to manage equipments. All countries have reviewed on policies to promote the quality such as educational requirements of professionals or restrictions on the duration of equipment usage. Various measures should be implemented to assure the qualitative ultrasound service.

Proposed Water Quality Monitoring Frequency for Risk Assessment in Korean Rivers and Streams (위해성평가 목적의 하천수 모니터링 빈도 연구: 국내상황을 고려한 적정빈도 제안)

  • Kwak, Jin Il;Yoon, Sung-Ji;Nam, Sun-Hwa;An, Youn-Joo
    • Journal of Korean Society on Water Environment
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    • v.28 no.3
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    • pp.473-478
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    • 2012
  • To protect human health and manage increasing hazardous chemicals in stream area, it is necessary to expand water quality hazardous items based on risk assessment with proper monitoring data. Also, it is essential to set up the suitable monitoring frequency to produce reliable exposure data to derive water quality guidelines. However, there has been no harmonized monitoring frequency for risk assessment in both domestic and international monitoring systems. In addition, the monitoring frequency for risk assessment has been selected as 'Research needs' in the International Conference on Deriving Environmental Quality Standards for the Protection of Aquatic Ecosystems (EQSPAE) of 2011. In this study, Cases of UNEP/WHO, EU, European countries, USEPA, ANZECC/ARMCANZ, CCME, Japan, and Korea were analyzed to propose the monitoring frequency for risk assessment. Monitoring frequencies depending on environmental conditions, monitoring object, measurement parameters, and monitoring duration were extensively collected. We observed that a monthly monitoring has been applied at most of organizations including EU, USEPA, and UNEP/WHO. In this study, monitoring frequency of minimum 6 times during 3 years were proposed to conduct the risk assessment based on the current domestic status. However, it is necessary to make agreements among interested parties, and perform additional studies about optimal monitoring frequency to protect the aquatic ecosystem and human health in Korean rivers and streams.