• Advances in concrete construction
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• 제11권4호
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• pp.285-298
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• 2021

This study focused on experimental evaluation of mechanical properties of pervious concrete mixtures with the aim of achieving higher values of strength while considering the associated costs. The effectiveness of key parameters, including cement content, water to cement ratio (W/C), aggregate to cement ratio (A/C), and sand replacement was statistically analyzed using paired-samples t-test, Taguchi method and one-way ANOVA. Taguchi analysis determined that in general, the role of W/C was more significant in increasing strength, both compressive and flexural, than cement content and A/C. It was found that increase in replacing percent of coarse aggregate with sand could undermine specimens to percolate water, though one-way ANOVA analysis determined statistically significant increases in values of strength of mixtures. Cost analysis revealed that higher strengths did not necessarily correspond to higher costs; in addition, increasing the cement content was not an appropriate scenario to optimize both strength and cost. In order to obtain the optimal values, response surface method (RSM) was carried out. RSM optimization helped to find out that W/C of 0.40, A/C of 4.0, cement content of about 330 kg/m3 and replacing about 12% of coarse aggregate with sand could result in the best values for strength and cost while maintaining adequate permeability.

• Asian Pacific Journal of Cancer Prevention
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• 제13권10호
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• pp.5125-5129
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• 2012

Economic decision models are being increasingly used to assess medical interventions. Advances in this field are mainly due to enhanced processing capacity of computers, availability of specific software to perform the necessary tasks, and refined mathematical techniques. We here estimated the incremental cost-effectiveness of ten strategies for colon cancer screening, as well as no screening, incorporating quality of life, noncompliance and data on the costs and profit of chemotherapy in Iran. We used a Markov model to measure the costs and quality-adjusted life expectancy of a 50-year-old average-risk Iranian without screening and with screening by each test. In this paper, we tested the model with data from the Ministry of Health and published literature. We considered costs from the perspective of a health insurance organization, with inflation to 2011, the Iranian Rial being converted into US dollars. We focused on three tests for the 10 strategies considered currently being used for population screening in some Iranians provinces (Kerman, Golestan Mazandaran, Ardabil, and Tehran): low-sensitivity guaiac fecal occult blood test, performed annually; fecal immunochemical test, performed annually; and colonoscopy, performed every 10 years. These strategies reduced the incidence of colorectal cancer by 39%, 60% and 76%, and mortality by 50%, 69% and 78%, respectively, compared with no screening. These approaches generated ICER (incremental cost-effectiveness ratios) of $9067, $654 and $8700 per QALY (quality-adjusted life year), respectively. Sensitivity analyses were conducted to assess the influence of various scales on the economic evaluation of screening. The results were sensitive to probabilistic sensitivity analysis. Colonoscopy every ten years yielded the greatest net health value. Screening for colon cancer is economical and cost-effective over conventional levels of WTP8.

• 한국안전학회지
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• 제11권1호
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• pp.121-128
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• 1996

Estimating the cost of injuries and "accidents" to an organization is very important to figure out about how much well each organization has run his company and how much efficiently he has got the results using a certain amount of the expense for safety. Despite the potential usefulness to management of information as to the cost of a company's "accidents", it is not customary accounting practice to make these data available. Of the two general kinds of costs forced on a company by its occupational injuries and "accidents", the insurance cost and uninsured cost, -the former is by far the easier to find out. But actually, this uninsured cost should be figured out at each company. Authors have designed the generalized model to figure out the above problem costs to establish its efficient safety control. One construction company has been a pilot for this study. It is found that efficient safety control cost should be 1.2%~l.3% of total selling amount by analyzing actual data for three years.g actual data for three years.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권12호
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• pp.6079-6097
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• 2018

Safety-related systems (SRSs) has widely used in shipbuilding and power generation to prevent fatal accidents and to protect life and property. Thus, SRS performance is a high priority. The safety integrity level (SIL) is the relative performance level of an SRS with regard to its ability to operate reliably in a safe manner. In this article, we proposed an optimal design procedure to achieve the targeted SIL of SRSs. In addition, a more efficient failure mode and effects diagnostic analysis (FMEDA) process and optimization model were developed to improve cost efficiency. Based on previous IEC 61508 diagnostic analyses that revealed unnecessary costs associated with excessive reliability, the new approach consists of two phases: (i) SIL evaluation by FMEDA, and (ii) solution optimization for achieving the target SIL with minimal cost using integer-programming models. The proposed procedure meets the required safety level and minimizes system costs. A case study involving a gas-detection SRS was conducted to demonstrate the effectiveness of the new procedure.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.150-156
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• 2004

Though the concept of Life-Cycle Cost (LCC) itself is not new, its effectiveness for planning, design, rehabilitation and maintenance/management of civil infrastructures is becoming increasingly recognized. For the decision problems as in the case of the LCC of plant facilities, equipments, bridge decks, pavements, etc., the Life-Cycle Cost Analysis (LCCA) is relatively simple, and thus its practical implementation is rather straightforward. However, when it comes to major infrastructures such as bridge, tunnels, underground facilities, etc., the LCCA problem becomes extremely complex because lack of cost data associated with various direct and indirect losses, and the absence of uncertainty data available for the assessment as well. As a result, the LCC studies have been largely limited only to those relatively simple LCCA problems of planning or conceptual design for making decisions. Accordingly, in the recent years, the researchers have pursued extensive studies on the LCC effectiveness mostly related to LCC models and frameworks for civil infrastructures. Moreover, recently the demand on the practical application of LCC effective decisions in design and maintenance is rapidly growing unprecedently in civil engineering practice. Indirction cost is very important on LCC formulation. But that is very difficult and complicate the estimation every LCC. The objective of this paper is to suggest efficient regression model for the estimation of indirect cost approach to the practical application of LCC for the design and rehabilitation of civil. infrastructures considering traffic, traffic network, detour condition, and workzone condition. In this paper, it performed the sensitivity analysis and correlation analysis of parameter for development of regression model of inflection cost.

• 한국건축시공학회지
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• 제21권5호
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• pp.409-420
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• 2021

건설공사 발주자에게 건설현장 근로자에 대한 안전보건관리 책무를 부여하는 안전보건대장 제도가 「산업안전보건법」 전부개정에 포함되어 도입되었다. 안전보건대장 제도에 대한 낮은 인식과 이행률로 발생되는 제도의 실효성 문제를 해결하기 위해서는 경제성 측면에서 제도의 효과성을 설명할 필요가 있으므로 본 연구에서는 안전보건대장 도입 당시 논의되었던 자료를 근거로 비용편익분석을 활용하여 안전보건제도 이행의 경제적 효과를 분석하였다. 안전보건대장 제도 이행에 있어 추가적인 비용이 발생하는 것은 설계안전보건대장의 작성 및 관리로 분석되었다. 작성비용과 산업재해 감소로 발생되는 직·간접적 편익을 비교한 결과 편익이 비용보다 높게 평가되었으므로 안전보건대장 제도는 건설공사 재해 감소와 경제적 효과를 발생시키는 것으로 판단된다.

• 한국문헌정보학회지
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• 제35권1호
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• pp.249-264
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• 2001

이 연구는 과학기술분야 해외 학술지의 비용대 효과를 파악하기 위하여 학술지의 이용당 비용(CPU)을 분석한 것이다. 대상 데이터는 한국과학기술정보연구원이 구독하고 있는 과학기술분야 학술지의 복사이용 빈도와 연간 구독비용이다. 학술지 구독비용과 복사이용빈도 분포, 학술지별 CPU, 주제분야별 CPU 등이 분석되었다. 학술지 총 구독비용의 40%가 전체 복사이용량의 80%를 제공하였으며, 학술지 구독비용은 복사이용빈도와 높은 상관관계가 있었으나 CPU와는 관련이 없는 것으로 나타났다.

• 대한안전경영과학회지
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• 제7권1호
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• pp.127-135
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• 2005

In general one can find an enormous number of studies about the productivity of land, labor and capital, very little has been done so far to communicate about the productivity of corporate information creating and information-consuming resources in ways that are useful to business executives. In view of the enormous share of corporate spending on information resources it would be useful in planning, budgeting, as well as in performance evaluation to measure how information resources are used in creating EVA(economic value-added). The effectiveness in deploying information resources has potentially a greater effect on corporate financial performance than any other economic influence. That in because corporate executives have greater discretion in directing what their information management staffs will do than in setting the terms for materials purchases, employee compensation, taxes or interest rates. The expenses for information are mostly in the form of overhead costs. Because expenses for information are mostly overhead costs and not for costs of goods, the prudent decision-maker should have a wide array of discretionary options available for allocating this resource. This study is intended for analysis the factors that having effects on the enterprise information productivity and is to description the factor using a foreign enterprise case study.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제3권4호
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• pp.139-148
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• 2014

IT의 발전과 더불어 금융권의 비대면 채널 역시 폭발적으로 증가되어왔다. 하지만 금융 시스템의 특성을 명확하게 반영한 규모 산정에 대한 모델의 부재로 인하여 예산 수립의 신뢰성 저하, 그리고 이에 따른 저가 수주 경쟁 등이 빈번하게 발생하였다. 이러한 규모 예측의 신뢰성 저하는 인터넷 뱅킹 시스템의 품질 저하로 이어져 금융 상품을 이용하는 고객에게 피해가 전해지고 있다. 따라서 본 논문에서는 기존 금융권에서 사용하는 규모 산정 기법의 두 종류인 FP 기반 규모 산정과 전문가 유추 기반의 규모 산정을 토대로 규모 산정 기법을 개선하여 보다 간편하고, 실제 금융 비대면 채널 수행 규모에 근접한 규모 예측 기법을 구축하고 이의 효용성을 회귀분석을 통하여 검증하였다. 그 결과, 기존 규모 산정 기법보다 실제 수행 규모와 상관관계 및 정확도가 증가된 인터넷 뱅킹 시스템을 위한 개선된 FP 기반 초기 규모예측 모델과 도구를 구축하였다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제8권4호
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• pp.316-321
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• 2008

Advanced computer network technology enables computers to be connected in an open network environment. Despite the growing numbers of security threats to networks, most intrusion detection identifies security attacks mainly by detecting misuse using a set of rules based on past hacking patterns. This pattern matching has a high rate of false positives and can not detect new hacking patterns, which makes it vulnerable to previously unidentified attack patterns and variations in attack and increases false negatives. Intrusion detection and analysis technologies are thus required. This paper investigates the asymmetric costs of false errors to enhance the performances the detection systems. The proposed method utilizes the network model to consider the cost ratio of false errors. By comparing false positive errors with false negative errors, this scheme achieved better performance on the view point of both security and system performance objectives. The results of our empirical experiment show that the network model provides high accuracy in detection. In addition, the simulation results show that effectiveness of anomaly traffic detection is enhanced by considering the costs of false errors.