• Title/Summary/Keyword: theory of evidence

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Topological Analysis of the Feasibility and Initial-value Assignment of Image Segmentation (영상 분할의 가능성 및 초기값 배정에 대한 위상적 분석)

  • Doh, Sang Yoon;Kim, Jungguk
    • Journal of KIISE
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    • v.43 no.7
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    • pp.812-819
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    • 2016
  • This paper introduces and analyzes the theoretical basis and method of the conventional initial-value assignment problem and feasibility of image segmentation. The paper presents topological evidence and a method of appropriate initial-value assignment based on topology theory. Subsequently, the paper shows minimum conditions for feasibility of image segmentation based on separation axiom theory of topology and a validation method of effectiveness for image modeling. As a summary, this paper shows image segmentation with its mathematical validity based on topological analysis rather than statistical analysis. Finally, the paper applies the theory and methods to conventional Gaussian random field model and examines effectiveness of GRF modeling.

TREATING UNCERTAINTIES IN A NUCLEAR SEISMIC PROBABILISTIC RISK ASSESSMENT BY MEANS OF THE DEMPSTER-SHAFER THEORY OF EVIDENCE

  • Lo, Chung-Kung;Pedroni, N.;Zio, E.
    • Nuclear Engineering and Technology
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    • v.46 no.1
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    • pp.11-26
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    • 2014
  • The analyses carried out within the Seismic Probabilistic Risk Assessments (SPRAs) of Nuclear Power Plants (NPPs) are affected by significant aleatory and epistemic uncertainties. These uncertainties have to be represented and quantified coherently with the data, information and knowledge available, to provide reasonable assurance that related decisions can be taken robustly and with confidence. The amount of data, information and knowledge available for seismic risk assessment is typically limited, so that the analysis must strongly rely on expert judgments. In this paper, a Dempster-Shafer Theory (DST) framework for handling uncertainties in NPP SPRAs is proposed and applied to an example case study. The main contributions of this paper are two: (i) applying the complete DST framework to SPRA models, showing how to build the Dempster-Shafer structures of the uncertainty parameters based on industry generic data, and (ii) embedding Bayesian updating based on plant specific data into the framework. The results of the application to a case study show that the approach is feasible and effective in (i) describing and jointly propagating aleatory and epistemic uncertainties in SPRA models and (ii) providing 'conservative' bounds on the safety quantities of interest (i.e. Core Damage Frequency, CDF) that reflect the (limited) state of knowledge of the experts about the system of interest.

An Empirical Analysis on Geographic Distribution of Physicians using the Central Place Theory (중심지이론을 이용한 의사의 지역적 분포에 관한 실증분석)

  • 김춘배;강명근;고상백;김한중;유승흠;손명세
    • Health Policy and Management
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    • v.6 no.2
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    • pp.58-90
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    • 1996
  • This study provides an empirical analysis of location competition for demand maximization by central place theory among physicians in nonmetropolitan areas of Korea. The results show that the primary care physicians distribute themselves evenly from urban communities to rural communities. The subspecialists, however, cluster together in major cities rather than decentralize themselves in rural counties. This study establishes the three statistical models : Primary care physicians, subspecialist physicians, and total physicians. Two models of primary care physicians and total physicians have a strong significance in multiple regression analysis (p=-.0001). The primary care model explains approximately 45% of the variation and the total physicians model explains approximately 70% of the variation in physician/1,000 population ratios across national counties. The subspecialist physicians model analysze the tobit regreassion because of the left consored and truncated values(57 cases = 0). In all three models, analysis of the coefficiencts for physician centralization degrees in the 0- to 5- and 5- to 10-km rings around the core county reveals each a positive and negative association betwee these degrees and the physician/1,000 population ratios in the core county. Also, the results provide moderate evidence that the relationship between clinic physicians and community hospitals is competitive, and the relationship between clinic physicians and pharmaceutists is synergistic. This suggests that public policy makers and local self-governing bodies must take an active role to ensure procider availability and the regional health planning in all nonmetropolitan areas of Korea.

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Relationship Between Profitability and Corporate Social Responsibility Disclosure: Evidence from Vietnamese Listed Banks

  • TRAN, Quoc Thinh;VO, Thi Diu;LE, Xuan Thuy
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.875-883
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    • 2021
  • In view of integration and development, compliance with regulations on information disclosure has important implications for users. Corporate social responsibility disclosure (CSRD) is an increasing concern of the community and society. CSRD always poses many challenges for the profitability of banks. The article uses the ordinary least square method to examine this relationship and employs timeseries data of five years from 18 Vietnamese listed banks from 2015 to 2019. The analysis is informed by Jensen and Meckling's Agency theory, Freeman's Stakeholder theory, and Dowling and Pfeffer's Legitimacy theory. The study results show that, with the CSRD dependent variable, return on assets (ROA) and net interest margin (NIM) have an opposite influence, but return on equity (ROE) has no effect on CSRD, while on the profitability dependent variable, CSRD has a different influence from ROA, ROE, and NIM. To enhance the relationship between CSRD and profitability, Vietnamese listed banks need to comply with CSRD as well as demonstrate responsibility to the community and society. Managers need to have clear development policies and strategies to ensure both profitability and responsibility regarding social and community activities. The State Securities Commission of Vietnam should enforce strict sanctions, conduct inspection, and complete evaluation criteria for Vietnamese listed banks.

Mullti-factor fusion Process for Pedestrian Risk Assesment (보행자의 위험도 산출을 위한 다중요인 융합 처리)

  • Ryu, Chang-Keun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.11 no.8
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    • pp.817-826
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    • 2016
  • The importance of common life safety is getting growth with modern society progress. This paper shows the extended way of assessment of danger that outcomes better result than the previous assessment based on crime frequency assessment. The assessment of this paper involves time, illusion degree, floating population and the personal condition. The evidence theory is not beneficial when the number of component increases, the assessment is more complex than before. This research solves the problem through the fuzzy theory adoption. This paper shows more advanced result that can express better danger awareness and get the adjective expression.

Difference in a venture's performance depending on the initial invested round: Focusing on absorptive capacity and a venture capital's reputation

  • Jeong, Ji-Hye;Kim, Ju-Hui;Nam, Dae-Il
    • 한국벤처창업학회:학술대회논문집
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    • 2017.04a
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    • pp.49-49
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    • 2017
  • This paper provides theory and evidence on how venture capital's (VC's) investment influence on new venture (NV) performance. Despite the wealth of research on the relationship between VC's investment and NV's performance, there are conflicts about whether the VC's investment can contribute to the performance of NV and NV's market value or not. For the accurate measure of the investment effect from VC, this research explored how the venture capital's investment in each development stage affects the NV's performance. The research was based on signaling theory and the theory of information asymmetry and looked for which factors affect a NV's performance. Using a sample of 364 firms went to public from 2000 to 2007, we find NV performance increases as NV acquires initial investment of VC in the early stage of development. While NV's potential absorptive capacity moderates the main relationship positively, we find no indication that NV's realized abortive capacity and NV's reputation have significant effect on the main relationship as moderators.

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Reliable Navigation of a Mobile Robot in Cluttered Environment by Combining Evidential Theory and Fuzzy Controller (추론 이론과 퍼지 컨트롤러 결합에 의한 이동 로봇의 자유로운 주변 환경 인식)

  • 김영철;조성배;오상록
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.05a
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    • pp.136-139
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    • 2001
  • This paper develops a sensor based navigation method that utilizes fuzzy logic and the Dempster-Shafer evidence theory for mobile robot in uncertain environment. The proposed navigator consists of two behaviors: obstacle avoidance and goal seeking. To navigate reliably in the environment, we make a map building process before the robot finds a goal position and create a robust fuzzy controller. In this paper, the map is constructed on a two-dimensional occupancy grid. The sensor readings are fused into the map using D-S inference rule. Whenever the robot moves, it catches new information about the environment and replaces the old map with new one. With that process the robot can go wandering and finding the goal position. The usefulness of the proposed method is verified by a series of simulations. This paper deals with the fuzzy modeling for the complex and uncertain nonlinear systems, in which conventional and mathematical models may fail to give satisfactory results. Finally, we provide numerical examples to evaluate the feasibility and generality of the proposed method in this paper.

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Qualitative study on the scaling experience through the application of comprehensive dental hygiene care : A grounded theory approach (포괄치위생관리 과정을 적용한 스케일링 수행 경험에 관한 질적 연구 : 근거이론적 접근)

  • Park, Seon-Mi;Moon, Sang-Eun;Kim, Yun-Jeong;Kim, Seon-Yeong;Cho, Hye-Eun;Kang, Hyun-Joo
    • Journal of Korean society of Dental Hygiene
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    • v.20 no.4
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    • pp.395-408
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    • 2020
  • Objectives: This study was performed in order to provide evidence-based data for the expected professional impact of dental hygienists, and to apply and disclose the comprehensive dental hygiene care process through an in-depth analysis of their scaling experience and investigation of the importance of an evidence-based scaling work performance. Methods: The data were collected from June 3, 2019 to October 3, 2019 by conducting in-depth individual interviews on 10 dental hygienists who are working in dental clinics and hospitals by region. The data were analyzed by using the grounded theory methodology, which is a field of qualitative research method. Results: Study results showed that the core category derived from the paradigm model and change process in this study was 'a process of becoming a mature professional outside practical work'. Conclusions: In this study, the participants were able to gain a sense of occupational accomplishment as dental hygienists by performing scaling based on the comprehensive dental hygiene care (CDHC) process, and to advance into professionals through continuous efforts and research in order to enhance their job competencies.

A Study on the Anthropometrical Method of Minimum Residential Space Standard for the Super-Aged Society of Korea - by Anthropometrical Data Application Methods of Karl H. E. Kroemer - (한국의 초고령사회를 대비한 최소주거면적 기준의 인체측정학적 방법 연구 - Karl H. E. Kroemer의 인체측정학적 데이터 적용 방법 -)

  • Lee, Ho Sung
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.23 no.1
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    • pp.15-24
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    • 2017
  • Purpose: Korea is expected to enter an aged society in 2018 and then a super-aged society in early 2025. The country's aging is progressing faster than any other country in the world. However, the foundation of the elderly friendly industry is weak, and measures at the government level are urgently needed. Especially, housing problems of the elderly are one of the most urgent measures to be taken. Korea does not have the minimum residential area standard for the elderly, and the current general minimum residential area standard is based on the survey of the housing situation without scientific evidence. Therefore, both standards need to be revised as soon as possible based on scientific evidence. Methods: The minimum residential area standard has been calculated following Karl H. E. Kroemer's Min or Max design also being called as-single cut and dual cut theory- as the maximum population value and minimum population value theory of Ernest J. McCormick. Therefore there is a need for a formula made using a few key factors, such as corresponding dimension, practical dimension, clearance, spare dimension, integrated dimension. These elements can be defined and used as formulas to calculate minimum residential area standards. Results: Assuming the results of the spatial variability in this study showed that it is possible to raise the standard of living in a terms of sustainable minimum size for the young, old and all residents. Implications: The government should set a minimum residential area standard with scientific grounds and set up a policy improving the life of people who live in an needy residential environment.

Dempster-Shafer Fusion of Multisensor Imagery Using Gaussian Mass Function (Gaussian분포의 질량함수를 사용하는 Dempster-Shafer영상융합)

  • Lee Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.20 no.6
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    • pp.419-425
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    • 2004
  • This study has proposed a data fusion method based on the Dempster-Shafer evidence theory The Dempster-Shafer fusion uses mass functions obtained under the assumption of class-independent Gaussian assumption. In the Dempster-Shafer approach, uncertainty is represented by 'belief interval' equal to the difference between the values of 'belief' function and 'plausibility' function which measure imprecision and uncertainty By utilizing the Dempster-Shafer scheme to fuse the data from multiple sensors, the results of classification can be improved. It can make the users consider the regions with mixed classes in a training process. In most practices, it is hard to find the regions with a pure class. In this study, the proposed method has applied to the KOMPSAT-EOC panchromatic image and LANDSAT ETM+ NDVI data acquired over Yongin/Nuengpyung. area of Kyunggi-do. The results show that it has potential of effective data fusion for multiple sensor imagery.