• Title/Summary/Keyword: critical criteria

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Deterministic Data Communication Architecture for Safety-Critical Networks in Nuclear Power Plants (원전 안전통신망을 위한 결정론적 데이터 통신 구조)

  • Park, Sung-Woo;Kim, Dong-Hoon
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.5
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    • pp.199-204
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    • 2006
  • To develop a safety-critical network in nuclear power plants that puts more stringent requirements than the competitive commercial ones do, we establish four design criteria - deterministic communication, explicit separation/isolation structure, reliability, verification & validation. According to those design criteria, the fundamental design elements are chosen as follows - a star topology, point-to-point physical link, connection-oriented link control and fixed allocation access control. After analyzing the design elements, we also build a communication architecture with TDM (Time Division Multiplexing) bus switching scheme. Finally, We develop a DDCNet (Deterministic Data Communication Network) based on the established architecture. The DDCNet is composed of 64 nodes and guarantees the transmission bandwidth of 10Mbps and the delay of 10 msec for each node. It turns out that the DDCNet satisfies the aforementioned design criteria and can be adequately utilized for our purpose.

Fuzzy ANP Application for Vender Prioritization (공급업체 우선순위 선정을 위한 Fuzzy ANP의 활용)

  • Jung, Uk
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.34 no.2
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    • pp.9-18
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    • 2011
  • Vender prioritization process is one of the most critical tasks of production and logistics management for many companies. Determining the most critical criteria for vender prioritization process is a vital means for a purchasing company to improve its supply chain productivity. This study discuss the use of a Fuzzy analytic network process (Fuzzy ANP) model which is an efficient tool to handle the fuzziness of the data involved in deciding the preferences of different criteria which are not independent. Also, the comparison of classical ANP and Fuzzy ANP is described using simulation with triangular distribution random number generation. It is shown that Fuzzy ANP model possesses some attractive properties and could be used as an alternative to the known vender prioritization methods.

Safety-critical 소프트웨어 V&V 지침서 개발 방법론

  • 김장열;이장수;권기춘
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.05a
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    • pp.233-238
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    • 1997
  • 본 논문에서는 Safety-critical 소프트웨어를 위한 V'||'&'||'V 지침서(guideline) 개발 방법론을 제시한다. 즉, 기존의 산업계 표준인 IEEE Std-1012, IEEE Std-1059에서 논의되고 있는 개념을 근간으로 "독립성(independence)", "소프트웨어 안전성 분석(software safety analysis)", "COTS 평가(evaluation) 기준", "다른 보증(assurance) 조직들간의 관련성(relationship)" 등의 필수 안전 항목들을 추가하여 원전 안전성 시스템(NPP safety system)을 위한 V'||'&'||'V 지침서 개발 방법론을 제시하였다 제시된 방법론에는 V'||'&'||'V 지침서의 범위(scope), 승인기준(acceptance criteria) 부분인 지침서 프레임(guideline framework), V'||'&'||'V activities 및 methods 부분인 타스크(task) entrance 및 exit 기준(criteria), 리뷰 및 감사(review and audit), 테스팅 그리고 V'||'&'||'V material의 QA 레코드(records) 및 형상관리, 소프트웨어 검증 및 확인 계획서(Software Verification and Validation Plan : SVVP) 생성 등의 내용을 기술하고, Safety-critical 소프트웨어 V'||'&'||'V 방법론도 함께 제시하였다.

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Strain-based plastic instability acceptance criteria for ferritic steel safety class 1 nuclear components under level D service loads

  • Kim, Ji-Su;Lee, Han-Sang;Kim, Jong-Sung;Kim, Yun-Jae;Kim, Jin-Won
    • Nuclear Engineering and Technology
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    • v.47 no.3
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    • pp.340-350
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    • 2015
  • This paper proposes strain-based acceptance criteria for assessing plastic instability of the safety class 1 nuclear components made of ferritic steel during level D service loads. The strain-based criteria were proposed with two approaches: (1) a section average approach and (2) a critical location approach. Both approaches were based on the damage initiation point corresponding to the maximum load-carrying capability point instead of the fracture point via tensile tests and finite element analysis (FEA) for the notched specimen under uni-axial tensile loading. The two proposed criteria were reviewed from the viewpoint of design practice and philosophy to select a more appropriate criterion. As a result of the review, it was found that the section average approach is more appropriate than the critical location approach from the viewpoint of design practice and philosophy. Finally, the criterion based on the section average approach was applied to a simplified reactor pressure vessel (RPV) outlet nozzle subject to SSE loads. The application shows that the strain-based acceptance criteria can consider cumulative damages caused by the sequential loads unlike the stress-based acceptance criteria and can reduce the overconservatism of the stress-based acceptance criteria, which often occurs for level D service loads.

The evolving classifications and epidemiological challenges surrounding chronic migraine and medication overuse headache: a review

  • Schembri, Emanuel;Barrow, Michelle;McKenzie, Christopher;Dawson, Andrew
    • The Korean Journal of Pain
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    • v.35 no.1
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    • pp.4-13
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    • 2022
  • Changes in diagnostic criteria, for example, the various International Classification of Headache Disorders criteria, would lead to changes in the outcomes of epidemiological studies. International Classification of Headache Disorders-1 was based mainly on expert opinion, yet most of the diagnostic criteria were reliable and valid, but it did not include chronic migraine. In its second version, the classification introduced chronic migraine, but this diagnosis resembled more a high-frequency migraine rather than the actual migraine transformation process. It also introduced medication overuse headache, but it necessitated analgesic withdrawal and subsequent headache improvement to be diagnosed as such. Hence patients having medication overuse headache could only be diagnosed in retrospect, which was an awkward situation. Such restrictive criteria for chronic migraine and medication overuse headache omitted a high proportion of patients. International Classification of Headache Disorders-3 allows a diagnosis of medication overuse headache due to combination analgesics if taken for at least 10 days per month for more than three months. Hence the prevalence rate of medication overuse headache and chronic migraine can increase compared to the previous version of the headache classification. Different criteria have been used across studies to identify chronic migraine and medication overuse headache, and therefore the information acquired from previous studies using earlier criteria becomes uncertain. Hence much epidemiological research would need to be interpreted cautiously or repeated with the most updated criteria, since the subjects in studies that apply the latest criteria may be phenotypically different from those in older studies.

A Generic Multi-Level Algorithm for Prioritized Multi-Criteria Decision Making

  • G., AlShorbagy;Eslam, Hamouda;A.S., Abohamama
    • International Journal of Computer Science & Network Security
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    • v.23 no.1
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    • pp.25-32
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    • 2023
  • Decision-making refers to identifying the best alternative among a set of alternatives. When a set of criteria are involved, the decision-making is called multi-criteria decision-making (MCDM). In some cases, the involved criteria may be prioritized by the human decision-maker, which determines the importance degree for each criterion; hence, the decision-making becomes prioritized multi-criteria decision-making. The essence of prioritized MCDM is raking the different alternatives concerning the criteria and selecting best one(s) from the ranked list. This paper introduces a generic multi-level algorithm for ranking multiple alternatives in prioritized MCDM problems. The proposed algorithm is implemented by a decision support system for selecting the most critical short-road requests presented to the transportation ministry in the Kingdom of Saudi Arabia. The ranking results show that the proposed ranking algorithm achieves a good balance between the importance degrees determined by the human decision maker and the score value of the alternatives concerning the different criteria.

Enhancing Similar Business Group Recommendation through Derivative Criteria and Web Crawling

  • Min Jeong LEE;In Seop NA
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.10
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    • pp.2809-2821
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    • 2023
  • Effective recommendation of similar business groups is a critical factor in obtaining market information for companies. In this study, we propose a novel method for enhancing similar business group recommendation by incorporating derivative criteria and web crawling. We use employment announcements, employment incentives, and corporate vocational training information to derive additional criteria for similar business group selection. Web crawling is employed to collect data related to the derived criteria from 'credit jobs' and 'worknet' sites. We compare the efficiency of different datasets and machine learning methods, including XGBoost, LGBM, Adaboost, Linear Regression, K-NN, and SVM. The proposed model extracts derivatives that reflect the financial and scale characteristics of the company, which are then incorporated into a new set of recommendation criteria. Similar business groups are selected using a Euclidean distance-based model. Our experimental results show that the proposed method improves the accuracy of similar business group recommendation. Overall, this study demonstrates the potential of incorporating derivative criteria and web crawling to enhance similar business group recommendation and obtain market information more efficiently.

Some Issues on Criterion for Kolmogorov-Smirnov Test in Credit Rating Model Validation (신용평가모형에서 콜모고로프-스미르노프 검정기준의 문제점)

  • Park, Yong-Seok;Hong, Chong-Sun
    • Communications for Statistical Applications and Methods
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    • v.15 no.6
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    • pp.1013-1026
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    • 2008
  • Kolmogorov-Smirnov(K-S) statistic has been widely used for the model validation of credit rating models. Validation criteria for the K-S statistic is empirically used at the levels of 0.3 or 0.4 which are much larger than the critical values of K-S test statistic. We examine whether these criteria are reasonable and appropriate through the simulations according to various sample sizes, type II error rates, and the ratio of bads among data. The simulation results say that the currently used validation criteria are too lower than values of K-S statistics obtained from any credit rating models in Korea, so that any credit rating models have good discriminatory power. In this work, alternative criteria of K-S statistic are proposed as critical levels under realistic situations of credit rating models.

Criteria for the Float Distribution (여유시간 분배기준에 관한 연구)

  • Lee Gul-Chan;Kim Kyung-Rai;Shin Dong-Woo
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.509-512
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    • 2003
  • The Critical Path Method(CPM) is an effective tool used for planning and scheduling. One of strong point in the CPM is what can calculate float. Float is able to prolong without having an effect on overall schedule of project, however concept and scope about ownership is not definite, because it is a by-product of project. Thus participants have had many dispute in using float because of their interests. In recent years, a few theories have evolved in an attempt to solve this problem. But the prior research did not make a reasonable distribution of float because their criteria of distribution was based on ratio for total project time. Actually, an application of float is achieved by participant's delay risk. Therefore. this paper proposes criteria for float distribution using delay risks, and the framework for the assessment of the delay risks.

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Deriving the Effective Improvement Elements of the Emergency Room in Large General Hospitals (신종 감염병 환자의 효율적 처치를 위한대형병원 응급실 관리요소의 중요도 도출)

  • Yoon, Songyi
    • Journal of Korean Critical Care Nursing
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    • v.8 no.2
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    • pp.66-79
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    • 2015
  • Purpose: This study aimed to derive the elements for effectively improving the management of emerging infectious diseases in the emergency room in large general hospitals. Methods: This research involved an analytic hierarchy process analysis of 10 experienced nurses working in a large general hospital located in the Seoul metropolitan area. The weighted values of the criteria for evaluating the importance of the management elements of patients with emerging infectious diseases in the emergency room of large general hospitals were derived using an analytic hierarchy process survey. Results: The results of the analytic hierarchy process analysis showed that experts considers responsiveness (0.291) as most important with respect to the criteria for the policy for isolation and control of infectious patients. The order of importance of the criteria for the policy for isolation and control of infectious patients were as follows: responsiveness (0.291), economical efficiency (0.257), feasibility (0.242), and sustainability (0.209). Subsequently, the weighted values of the management of the policy elements were determined based on the derived importance of the criteria mentioned above. These were, in order of priority, the construction of communication channels with the government authorities when dealing with emerging infectious diseases (15.9%), the equipment and provision of personal protective equipment to protect nurses from infection and dissemination of material (14.6%), and the operation of the isolation room and patient separation systems (14.1%). Conclusion: This study suggests critical strategies for infection control during a pandemic of emerging infectious disease.