• 한국산업보건학회지
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• 제32권3호
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• pp.253-267
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• 2022

Objectives: This study was performed to check whether the CRS (Chemical Ranking and Scoring) system is appropriate as a method to determine substances as candidates for substances subject to permission and to apply this system to the selection of candidates for substances subject to permission. Methods: A risk score was obtained by multiplying the hazard score and the exposure score and then ranking them. The hazard sub-indicators are carcinogenicity, germ cell mutagenicity, reproductive toxicity, specific target organ toxicity-repeated exposure, respiratory sensitization and endocrine disrupting chemicals. Exposure sub-indicators are persistence, bioaccumulation and emission volume. Sensitivity analysis was performed for missing values. Correlation analysis and multivariable linear regression analysis were performed among hazard, exposure and risk in order to confirm that CRS was an appropriate method. Results: As a result of the sensitivity analysis on missing values, it was confirmed that the effect on the risk ranking was not sensitive. Correlation and regression analysis confirmed that exposure had a greater effect on risk than hazard. Conclusions: The CRS system, which derives a risk score using a hazard and exposure score, is judged to be appropriate as a method for the selection of preliminary of candidates for substances subject to permission. Benzene, cadmium, nickel, and cobalt were selected as priority candidates for substances subject to permission.

• 대한산업공학회지
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• 제25권2호
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• pp.184-191
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• 1999

The k most vital arcs (k-MVA) of a maximum flow problem is defined as those k arcs whose simultaneous removal from the network causes the greatest decrease in the throughput capability of the remaining system between a specified pair of nodes. In this study, we present a method for determining all the k-MVA in maximum flow problem using a minimal cardinality cut algorithm and k-th minimal cut ranking algorithm. For ranking cardinality cuts, we use Hamacher's ranking algorithm for cut capacity and by comparing present residual capacity of cardinality cut with expected residual capacity of next cardinality cut, we also present termination condition for this algorithm. While the previous methods cannot find all the alternatives for this problem, a method presented here has advantage of determining all the k-MVA.

• 조명전기설비학회논문지
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• 제22권2호
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• pp.148-154
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• 2008

송전용량산정은 최근에 많은 전력회사에서 중요한 문제로 부각되어 왔다. 한전 시스템의 경우 전체송전용량은 주로 전압 안정도에 의해 제한을 받고 있으며, 전체송전용량 산정을 위하여서는 수많은 상정사고들에 대해서 분석하여야 한다. 따라서 전체송전용량 결정을 위한 전압안정도 측면에서의 상정사고를 효과적으로 선정하는 기법이 절실히 요청되고 있으며, 본 논문에서는 전체송전용량 결정을 위한 전압안정도 측면에서의 상정사고를 효과적으로 선정하는 새로운 상정사고 선정지수를 제시한다. 그리고 이 전체송전용량 결정을 위한 전압안정도 측면에서의 상정사고 선정지수의 효율성을 검증하기 위해 이 지수를 한전의 실계통에 적용하고 PSS/E 패키지와 개발한 IPLAN 프로그램을 사용하여 이 지수의 상정사고 선정에 대한 효용성이 분석된다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4323-4326
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• 2016

Background: The cancer mortality-to-incidence ratio (MIR) has been established as an important measure of health disparities in local and global circumstances. Past work has corroborated a linkage between the colorectal cancer MIR and the World Health Organization (WHO) Health System ranking. The literature further documents many Asian countries having incomplete cancer registries and a lack of comprehensive colorectal cancer screening guidelines. Materials and Methods: The colorectal cancer MIR values for 23 Asian countries were calculated from data obtained from the 2012 GLOBOCAN database. The 2000 World Health Organization (WHO) Health System rankings were used as a proxy for health system infrastructure and responsiveness. A regression equation was calculated with the MIR as the dependent variable and the WHO Health System ranking as the independent variable. Predicted MIR values were next calculated based on the regression results. Actual MIR values that exceeded 0.20 from the predicted MIR were removed as 'divergent' points. The regression equation was then re-plotted. Goodness-of-fit for both regressions was assessed by the R-squared test. Results: Asian countries have a relatively wide colorectal cancer MIR range, from a minimum of 0.24 to a maximum of 0.86. For the full dataset, the adjusted R-squared value for this regression was 0.53. The equation was then used to calculate a predicted MIR, whereby two data points were identified as 'divergent' and removed. The adjusted R-squared for the edited dataset increased to 0.66. Conclusions: Asian countries have a marked range in their colorectal cancer MIR values and there is a strong correlationwith the WHO Health System ranking. These results corroborate the contribution of the MIR as a potentially robust tool in monitoring changes in colorectal cancer care for Asian nations.

• 조명전기설비학회논문지
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• 제12권1호
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• pp.20-25
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• 1998

본 논문은 전력설비의 신속한 상정사고 선택을 위한 앨고리즘을 제시한다. 이 방법은 DC법에 의한 선로와 모선사이의 감도계수인 GSDF(Generation Shigt Distribution Factor)를 이용하여 계산되는 선로개방분배계수 (LODF : Line Outage Distribution Factor)를 사용하여 정상상태에서의 선로조류로부터 상정사고시의 선로조류를 계산하였다. 상정사고 선택을 신속히 하기 위하여 정상상태에서 용량대비 선로조류가 35〔%〕(154〔kV〕에서는 60〔%〕)이상의 선로만을 대상으로 하였다. 본 논문에서 제시한 앨고리즘 및 프로그램의 효율성을 입증하기 위하여 6모선 11선로 모델계통을 선정하여 적용하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.760-763
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• 1996

This paper presents an algorithm for the contingency ranking in a power system. The method utilizes line outage distribution factors(LODF) which are established from DC load flow solutions. The LODF are formulated using changes in network power generations to simulate the outaged line from the network. To abtain better ranking. one can take a line loading of 60% over into account in the computation of PI. The proposed algorithm has been validated in tests on a 6-bus test system.

• Environmental Analysis Health and Toxicology
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• 제19권1호
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• pp.81-91
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• 2004

Although it is suggested that risk -based management plan is needed to manage air pollution effectively, we have no resources enough to evaluate all aspects of substances and set priorities. So we need to develop a logical and easy risk-based priority setting method. However, it if impossible that only one generic system that is consistent with all the use is developed. In this study, we proposed a human health risk based priority-setting method for hazardous air pollutants, and ranked priorities for this method. First of all, after investigating previous chemical ranking and scoring systems, we chose appropriate indicators and logics to goal of this study and made a chemical priority ranking method using these. As results, final scores in priority ranking method were derived for 25 substances, and ethylene oxide, acrylonitrile and vinyl chloride were included in high ranks. In addition, same substances were highly ranked when using default values like when using no default, but the scores of hydrofluoric acid and ryan and compounds were sensitive to default values. This study could be important that priorities were set including toxicity type and quality and local inherent exposure conditions and we can set area-specific management guidelines and survey plans as a screening tool.

• 산업경영시스템학회지
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• 제42권1호
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• pp.87-94
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• 2019

A wireless sensor network is emerging technology and intelligent wireless communication paradigm that is dynamically aware of its surrounding environment. It is also able to respond to it in order to achieve reliable and efficient communication. The dynamical cognition capability and environmental adaptability rely on organizing dynamical networks effectively. However, optimally clustering the cognitive wireless sensor networks is an NP-complete problem. The objective of this paper is to develop an optimal sensor network design for maximizing the performance. This proposed Ranking Artificial Bee Colony (RABC) is developed based on Artificial Bee Colony (ABC) with ranking strategy. The ranking strategy can make the much better solutions by combining the best solutions so far and add these solutions in the solution population when applying ABC. RABC is designed to adapt to topological changes to any network graph in a time. We can minimize the total energy dissipation of sensors to prolong the lifetime of a network to balance the energy consumption of all nodes with robust optimal solution. Simulation results show that the performance of our proposed RABC is better than those of previous methods (LEACH, LEACH-C, and etc.) in wireless sensor networks. Our proposed method is the best for the 100 node-network example when the Sink node is centrally located.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권1호
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• pp.16-25
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• 2013

The Korean groundwater law regulates 20 groundwater contamination parameters, including 14 specific harmful substances. Expanding the number of groundwater quality standards are needed to cope with recent groundwater quality deterioration due to the use of various chemicals. Chemical ranking and scoring system (CRS) is a scientific tool to sort priority chemicals by considering exposure and toxicity potentials. In this study, we developed a CRS for scoring and ranking of possible groundwater pollutants and screened priority substances to be later considered in the Korean standard expansion. Chemical Ranking Of groundWater pollutaNts (CROWN) incorporates important parameters consisting of exposure potential, human and water ecotoxicity, interests, and certainty. Furthermore, CROWN additionally evaluated existence of other media standards to consider impacts by contamination of other media. The 197 substances that were common to 9 countries were selected first. CROWN evaluated and ranked each chemical, and finally suggested priority substances. Suggested priority substances were classified into two groups according to the groundwater use purposes: drinking and non-drinking. The priority substances were further classified into $1^{st}$ and $2^{nd}$ group priorities. The $1^{st}$ group consists of 75 substances, including the all the Korean groundwater standard parameters. CROWN will be used in selecting groundwater pollutants for possible inclusion in the Korean standard expansion.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.1-12
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• 2015

The purpose of this study is to highlight the National Classification System related to cleanup the soil contaminated sites and to provide some guidance to address the priority management rank system before the remediation for Busan metropolitan city. Based on the previous soil investigation data, the quantitative classification of vulnerable areas for soil pollution was performed to successfully manage the contaminated sites in Busan. Ten evaluation factors indicating the high soil pollution possibility were used for the priority management ranking system and 10 point was assigned for each factor which was evenly divided by 10 class intervals. For 16 Gu/Guns in Busan, the score of each evaluation factor was assigned according to the ratio of the area (or the number) between in each Gu (or Gun) and in Busan. Ten scores for each Gu (or Gun) was summed up to prioritize the vulnerable Gu or Guns for soil pollution in Busan. Results will be available to determine the most urgent area to cleanup in each Gu (or Gun) and also to assist the municipal government to design a successful and cost-effective site management strategy in Busan.