• 제목/요약/키워드: Quantitative Approaches

검색결과 416건 처리시간 0.022초

뇌 PET 영상 정량화 및 파라메터영상 구성을 위한 선형분석기법 (Linearized Methods for Quantitative Analysis and Parametric Mapping of Brain PET)

  • 김수진;이재성
    • Nuclear Medicine and Molecular Imaging
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    • 제41권2호
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    • pp.78-84
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    • 2007
  • Quantitative analysis of dynamic brain PET data using a tracer kinetic modeling has played important roles in the investigation of functional and molecular basis of various brain diseases. Parametric imaging of the kinetic parameters (voxel-wise representation of the estimated parameters) has several advantages over the conventional approaches using region of interest (ROI). Therefore, several strategies have been suggested to generate the parametric images with a minimal bias and variability in the parameter estimation. In this paper, we will review the several approaches for parametric imaging with linearized methods which include graphical analysis and mulilinear regression analysis.

Quantitative Approaches in Use to Assess Cancer Risk

  • Anderson Elizabeth L.
    • 대한예방의학회:학술대회논문집
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    • 대한예방의학회 1994년도 교수 연수회(환경)
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    • pp.450-468
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    • 1994
  • Scientists have long used conventional toxicological methods to establish 'safe levels of exposure' for chemicals presumed to have threshold health effects or doses below which significant effects are unlikely to occur. These same methods cannot be used to establish safe levels of exposure for non-threshold pollutants. such as carcinogens. Therefore. Federal regulatory agencies in the United States are using risk assessment methods to provide information for public health policy decisions concerning increases in risk associated with increases in exposure to carcinogenic and other non-threshold pollutants. Acceptable exposure/risk levels are decided by policymakers who consider descriptions and estimates of risks together with social and economic benefits from the uses of the chemical. 1bis paper focuses on the development of quantitative risk assessment approaches by Federal regulatory agencies in the United States, and identifies the mathematical models currently being used for risk extrapolation. including their inherent uncertainties. The uncertainties and limitations of these methods have led some scientists to question the utility of quantitative risk extrapolation. The experience of the; U.S. Environmental Protection Agency (EPA). as summarized in this paper. can provide a realistic basis for evaluating the pros and cons. Finally. shortcomings in current risk assessment methods and their use in policy decisions are explored. and areas for possible improvement. given current scientific knowledge. are identified.

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정보 보안 방안 선택을 위한 퍼지 AHP 방법의 비교 검토 (Comparison of Fuzzy AHP Decision Making Approaches for Selection among Information Security Systems)

  • 이경근;류시욱
    • 한국정보시스템학회지:정보시스템연구
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    • 제19권3호
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    • pp.59-73
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    • 2010
  • Along with advance of information technology, value of information is growing much more than ever. And nearly all organizations pay great attentions to information security to protect their own important informations against every kind of hazardous accidents. Therefore, organizations want to select best information security system among many possible alternatives. For this purpose, several fuzzy AHP decision making approaches can be utilized. In this study, we consider a number of qualitative and quantitative factors to evaluate security systems and then apply three fuzzy AHP approaches for simple case to compare the results from three approaches. We find that final decision depends on both fuzzy AHP methods and degree of fuzziness.

Emerging Practices in Foresight and Their Use in STI Policy

  • Daheim, Cornelia;Hirsch, Sven
    • STI Policy Review
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    • 제6권2호
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    • pp.24-53
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    • 2015
  • Foresight, a major methodological tool in the STI policy toolbox, has recently featured new directions in methodological development, becoming influenced by progress in information and communication technologies and online tools. However, no overview of these directions has been available so far. Based on a literature review, an interactive workshop, and an international expert survey as well as expert interviews, the research presented here attempts to shed light onto some of the relevant issues by providing a structured overview of recent changes in order to further the debate on the future directions of methodological development in foresight. The paper outlines four clusters of emerging approaches in foresight:Integrated qualitative and quantitative approaches, IT-based and automated foresight, experiential foresight including new forms of communication and interaction such as visualization and gaming, and open and crowd-sourced approaches. The benefits and challenges of the approaches known so far are categorized and summarized, and areas of potential use for each of the clusters in STI contexts are identified.

Comparative Study of Contrast-Enhanced Ultrasound Qualitative and Quantitative Analysis for Identifying Benign and Malignant Breast Tumor Lumps

  • Liu, Jian;Gao, Yun-Hua;Li, Ding-Dong;Gao, Yan-Chun;Hou, Ling-Mi;Xie, Ting
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권19호
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    • pp.8149-8153
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    • 2014
  • Background: To compare the value of contrast-enhanced ultrasound (CEUS) qualitative and quantitative analysis in the identification of breast tumor lumps. Materials and Methods: Qualitative and quantitative indicators of CEUS for 73 cases of breast tumor lumps were retrospectively analyzed by univariate and multivariate approaches. Logistic regression was applied and ROC curves were drawn for evaluation and comparison. Results: The CEUS qualitative indicator-generated regression equation contained three indicators, namely enhanced homogeneity, diameter line expansion and peak intensity grading, which demonstrated prediction accuracy for benign and malignant breast tumor lumps of 91.8%; the quantitative indicator-generated regression equation only contained one indicator, namely the relative peak intensity, and its prediction accuracy was 61.5%. The corresponding areas under the ROC curve for qualitative and quantitative analyses were 91.3% and 75.7%, respectively, which exhibited a statistically significant difference by the Z test (P<0.05). Conclusions: The ability of CEUS qualitative analysis to identify breast tumor lumps is better than with quantitative analysis.

Review of Biological Network Data and Its Applications

  • Yu, Donghyeon;Kim, MinSoo;Xiao, Guanghua;Hwang, Tae Hyun
    • Genomics & Informatics
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    • 제11권4호
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    • pp.200-210
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    • 2013
  • Studying biological networks, such as protein-protein interactions, is key to understanding complex biological activities. Various types of large-scale biological datasets have been collected and analyzed with high-throughput technologies, including DNA microarray, next-generation sequencing, and the two-hybrid screening system, for this purpose. In this review, we focus on network-based approaches that help in understanding biological systems and identifying biological functions. Accordingly, this paper covers two major topics in network biology: reconstruction of gene regulatory networks and network-based applications, including protein function prediction, disease gene prioritization, and network-based genome-wide association study.

Understanding postal delivery areas in the Republic of Korea using multiple unsupervised learning approaches

  • Han, Keejun;Yu, Yeongwoong;Na, Dong-gil;Jung, Hoon;Heo, Younggyo;Jeong, Hyeoncheol;Yun, Sunguk;Kim, Jungeun
    • ETRI Journal
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    • 제44권2호
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    • pp.232-243
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    • 2022
  • Changes in household composition and the residential environment have had a considerable impact on the features of postal delivery regions in recent years, resulting in a large increase in the overall workload of domestic postal delivery services. In this paper, we provide complex analysis results for postal delivery areas using various unsupervised learning approaches. First, we extract highly influential features using several feature-engineering methods. Then, using quantitative and qualitative cluster analyses, we find the distinctive traits and semantics of postal delivery zones. Unsupervised learning approaches are useful for successfully grouping postal service zones, according to our findings. Furthermore, by comparing a postal delivery region to other areas in the same group, workload balancing was achieved.

컬러 카메라를 이용한 측면유동 면역 어세이 정량분석 방법 (A Method for Quantitative Measurement of Lateral Flow Immunoassay Using Color Camera)

  • 박종원
    • 대한의용생체공학회:의공학회지
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    • 제35권1호
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    • pp.1-7
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    • 2014
  • Among semi-quantitative or fully quantitative lateral flow assay readers, an image sensor-based instrument has been widely used because of its simple setup, cheap sensor price, and compact equipment size. For all previous approaches, monochrome CCD or CMOS cameras were used for lateral flow assay imaging in which the overall intensities of all colors were taken into consideration to estimate the analyte content, although the analyte related color information is only limited to a narrow wavelength range. In the present work, we introduced a color CCD camera as a sensor and a color decomposition method to improve the sensitivity of the quantitative biosensor system which utilizes the lateral flow assay successfully. The proposed setup and image processing method were applied to achieve the quantification of imitatively dispensed particles on the surface of a porous membrane first, and the measurement result was then compared with that using a monochrome CCD. The compensation method was proposed in different illumination conditions. Eventually, the color decomposition method was introduced to the commercially available lateral flow immunochromatographic assay for the diagnosis of myocardial infarction. The measurement sensitivity utilizing the color image sensor is significantly improved since the slopes of the linear curve fit are enhanced from 0.0026 to 0.0040 and from 0.0802 to 0.1141 for myoglobin and creatine kinase (CK)-MB detection, respectively.

Polarization Spectral Imaging System for Quantitative Evaluation of Port Wine Stain Blanching Following Laser Treatment

  • Jung, Byung-Jo
    • Journal of the Optical Society of Korea
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    • 제7권4호
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    • pp.234-239
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    • 2003
  • Objective methods to assess quantitatively port wine stain (PWS) blanching in response to laser therapy are needed to improve laser therapeutic outcome. Previous studies have attempted to assess objectively PWS color based on point measurement devices. To date, these approaches have typically been limited by a number of factors such as small test area and need for contact. To address these issues, a polarization spectral imaging system and an image analysis method have been developed to evaluate quantitatively erythema and melanin content distribution in skin. The developed polarization spectral imaging system minimizes artifacts such as glaring, shadowing, and non-uniform illumination that interfere with image fidelity. Furthermore, the image analysis method has been employed to get images of skin melanin and erythema indices from the acquired color images for quantitative analysis. Finally, using PWS patient color image, the effectiveness in laser treatment of PWS was evaluated by calculating relative erythema index image that is the relative erythema index of PWS region to the normal region. The developed device and analysis method appears to be a simple and effective method for quantitative analysis of PWS blanching.

조선해양 산업에서의 ERP 구축 사례 연구 (A Case Study on ERP Adoption in Shipbuilding and Marine Engineering Industry)

  • 정성립;이재광;조현
    • 한국IT서비스학회지
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    • 제12권1호
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    • pp.189-199
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    • 2013
  • As many organizations have adopted and implemented ERP systems, concerns about ERP performance also have increased. Former researches studied the ERP implementation of general large or medium size enterprises but there are not enough studies on ERP systems of a specific industry domain. In this paper, we introduce a case study on ERP adoption methodology of global leading company 'D' in shipbuilding and marine engineering industry. We examined ERP implementation background, method and scope and evaluated ERP performance in perspective of both quantitative and qualitative approaches. Quantitative research usually examines ERP performance based on financial statements and qualitative study typically examines organization change or improvement. As a result, ERP implementation in shipbuilding and marine industry can improve quantitative aspects such as cost, human resource and organization performance. As qualitative analysis, business process and tools can be unified and management transparency can be improved by ERP implementation. The result of this paper will be useful guideline for organizations which are considering ERP systems.