• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.221.1-221
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• 1999

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.2179-2183
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• 2009

As urbanization is progressed, the network for distributing water in a basin become complex due to the spatial expansion and parameter uncertainties of water supply systems. When a long range water supply plan is determined, the total construction and operation cost has to be evaluated with the system components and parameter uncertainties as many as possible. In this paper, the robust optimization approach of Bertsimas and Sim is applied in a hypothetical system to find a solution which remains feasible under the possible parameter uncertainties having the correlation effect between the uncertain coefficients. The system components to supply, treatment, and transport water are included in the developed water supply system and construction and expansion of the system is allowed for a long-range period. In this approach, the tradeoff between system robustness and total cost of the system is evaluated in terms of the degree of conservatism which can be converted to the probability of constraint violation. As a result, the degree of conservatism increases, the total cost is increased due to the installation of large capacity of treatment and transportation systems. The applied robust optimization technique can be used to determine a long-range water supply plan with the consideration of system failure.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.389-396
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• 2003

This paper presents experimental validation of the enhanced reference stress based J estimates for circumferential through-wall cracked pipes, recently proposed by authors. Using the pipe test data for circumferential through-wall cracked pipes, the predicted fracture initiation and maximum moments according to the proposed enhanced reference stress method are compared with experimental ones as well as predictions from the R6 method. The results show that both the R6 method and the proposed method give conservative estimates of initiation and maximum moments for circumferential through-wall cracked pipes, compared to experimental data. For longer cracks, the proposed method reduces conservatism embedded in estimated J according to the R6 method, and the resulting predictions are less conservative, compared to those from the R6 method. For shorter cracks, on the other hand, the proposed method reduces possible non-conservatism embedded in estimated J according to the R6 method, and the resulting predictions are slightly more conservative.

• 대한기계학회논문집A
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• 제27권4호
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• pp.638-646
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• 2003

This paper presents experimental validation of the enhanced reference stress based J estimates for circumferential through-wall cracked pipes. recently proposed by authors. Using the pipe test data for circumferential through-wall cracked pipes, the predicted fracture initiation and maximum moments according to the proposed enhanced reference stress method are compared with experimental ones as well as predictions from the R6 method. The results show that both the R6 method and the proposed method give conservative estimates of initiation and maximum moments for circumferential through-wall cracked pipes, compared to experimental data. For longer cracks, the proposed method reduces conservatism embedded in estimated J according to the R6 method, and the resulting predictions are less conservative, compared to those from the R6 method. For shorter cracks, on the other hand, the proposed method reduces possible non-conservatism embedded in estimated J according to the R6 method, and the resulting predictions are slightly more conservative.

• 에너지공학
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• 제24권4호
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• pp.175-182
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• 2015

발전소 안전성 평가 시 최적해석 코드를 사용함으로써 코드 모델의 보수성을 최소화하고, 해석 조건의 보수성을 확보하도록 다양한 범위의 초기조건을 표본 추출하여 결정하는 방법을 수립하였다. 제시된 방법론의 적용성을 확인하기 위하여 국내 경수로를 참조발전소로 선정하고 첨두 압력이 주요 안전기준이 되는 복수기 진공상실사고에 대한 안전성평가를 수행하였다. MOSAIQUE 프로그램을 이용하여 100가지 다른 초기조건을 생성하고, 자동적으로 과도해석을 수행함으로써 가장 보수적인 결과에 대한 첨두 압력을 얻을 수 있었다. 새로운 방법론에 의해 얻어진 안전여유도는 기존의 방법론과 유사한 수준을 가졌는데, 안전성 평가를 위해 소요되는 시간과 노력을 획기적으로 줄일 수 있음을 확인하였다.

• 대한가정학회지
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• 제39권6호
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• pp.1-14
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• 2001

The purpose of this research is to observe the differences in consumers behavior on clothes care based on their different lifestyles and different demographic characteristics. The research surveyed 267 women of 20 years old or older living in Taegu City. SPSS package was used for data analysis and frequency, percentage, average, standard deviation, factor analysis, cluster analysis, ANOVA(analysis of valiance). and Duncan test were used The results are as follows: 1. Lifestyle factors for the research object were found as 'Consumption-oriented','family-oriented', 'Economic-oriented','Leisure-oriented','conservatism-oriented'. The categories for analysis according to these factors are classified into 5 categories, category 1 is Leisure/Family-oriented group, category 2 Consumption/Leisure avoidance-oriented group, category 3 Economy/Family Apathy-oriented group, category 4 Conservatism-oriented group, and category 5 Consumption/Innovation group. Five factors for behavior on clothes care are found, including washing method, interest in detergent, environmental behavior, washing effectiveness, and management after washing 2. Behavior on clothes care based on lifestyle groups showed a meaningful difference according to the following: Interest in detergent(p<.05 level), environmental behavior(p<.01 level), and washing effectiveness(p< .01 level) 3. In demographic variations (such as age, monthly income, monthly expenditure on clothes), there is a meaningful difference in behavior on clothes care, such as interest in detergent or management after washing, according to different age groups. However, no meaningful difference is found in behavior on clothes care according to other demographic characteristics.

• Nuclear Engineering and Technology
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• 제32권5호
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• pp.465-476
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• 2000

In a nuclear power plant, steam generator tubes cover a major portion of the primary pressure-retaining boundary. Thus very conservative approaches have been taken in the light of steam generator tube integrity According to the present criteria, tubes wall-thinned in excess of 40% should be plugged whatever causes are. However, many analytical and experimental results have shown that no safety problems exist even with thickness reductions greater than 40%. The present criterion was developed about twenty years ago when wear and pitting were dominant causes for steam generator tube degradation. And it is based on tubes with single cracks regardless of the fact that the appearance of multiple cracks is more common in general. The objective of this study is to review the conservatism of the present plugging criteria of steam generator tubes and to propose a new coalescence model for two adjacent through-wall cracks existing in steam generator tubes. Using the existing failure models and experimental results, we reviewed the conservatism of the present plugging criteria. In order to verify the usefulness of the proposed new coalescence model, we performed finite element analysis and some parametric studies. Then, we developed a coalescence evaluation diagram.

• Journal of Information Science Theory and Practice
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• 제8권1호
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• pp.6-19
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• 2020

When information professionals deal with other disciplines in the course of digital humanities projects, they often assume that they are dealing with 'needful users' who have an 'information gap' to fill. This paper argues that the traditional view that information/knowledge is transferred from an information specialist donor to a domain specialist receiver is no longer appropriate in the digital humanities context, where the gap-and-search (or gap-and-filler) approach to information has given way to more direct, explorative engagement with information. The paper asks whether information science and the practising profession are ready for this paradigm shift and examines information science conservatism in two common collaboration scenarios, library support and digital development. It is shown that information science theory still assumes a traditional donor role in both scenarios. How information scientists deal with conservatism in practice is discussed in the example of the Prior project, in which the information science team exerted an ambiguous, hybrid approach with both conservative and non-conservative elements. Finally, two rather hypothetical answers are offered to the question of how information professionals should approach scholarly collaboration in the digital humanities context, where users have ceased to be supplicants. From a purely pragmatic perspective, information scientists need to shift their focus from information needs to research practices and the implications of these practices for digital information systems. More fundamentally, the emergence of digital humanities challenges information professionals to transform information systems designed for searching into digital objects that can be explored more freely by the digital humanities community.

• Nuclear Engineering and Technology
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• 제35권2호
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• pp.154-164
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• 2003

The explicit consideration of different pressurization rates in estimating the probabilities of containment failure modes has a profound effect on the confidence of containment performance evaluation that is so critical for risk assessment of nuclear power plants. Except for the sophisticated NUREG-1150 study, many of the recent containment performance analyses (through Level 2 PSAs or IPE back-end analyses) did not take into account an explicit distinction between slow and fast pressurization in their analyses. A careful investigation of both approaches shows that many of the approaches adopted in the recent containment performance analyses exactly correspond to the NUREG-1150 approach for the prediction of containment failure mode probabilities in the presence of fast pressurization. As a result, it was expected that the existing containment performance analysis results would be subjected to greater or less conservatism in light of the ultimate failure mode of the containment. The main purpose of this paper is to assess potential conservatism of a plant-specific containment performance analysis result in light of containment failure mode probabilities.

• 경영과정보연구
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• 제32권5호
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• pp.261-285
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• 2013

본 연구는 이익조정과 회계보수주의에 대한 관계를 분석한다. 또한 이익조정과 보수주의에 대한 보다 분명한 관계를 분석하기 위해 이익조정의 개연성이 클 것으로 판단되는 적자회피기업과 Big-bath기업을 대상으로 이익조정과 보수주의의 관계를 분석하였다. 적자회피기업은 Subramanyam(1996)에 의해 당기의 비재량적 이익(당기순이익-재량적 발생액)이 음(-)이면서 보고이익이 양(+)인 기업(표본I) 또는 당기 비재량적 이익이 전연도 보고이익을 하회하면서 당기이익이 전연도 이익을 상회하는 기업(표본II)을 조정 전 이익의 적자를 회피하기 위한 적자회피기업으로 간주하였다. 그리고 Big-bath기업은 Strong and Meyer(1987)의 연구를 인용하여 비재량적 이익이 양(+)이면서 보고이익이 음(-)인 기업(표본III) 그리고 비재량적 이익이 전연도 보고이익을 상회하면서 당기보고이익이 전연도 보고이익을 하회하는 기업(표본IV)을 Big-bath기업으로 구분하였다. 적자회피기업과 Big-bath기업의 요건을 충족하지 않는 기업들은 비 이익조정기업으로 간주하여 주요표본기업들에 대한 통제기업으로 분류하였다. 분석결과, 적자회피기업(표본I, II)은 통제기업에 비해 회계 보수성이 낮은 것으로 분석되었다. 이는 적자회피기업의 이익상향 조정유인을 감안할 때 낮은 보수주의수준은 이익조정과 보수주의에 대한 음(-)의 관련성을 간접적으로 제시한 결과이다. 그러나 적자회피기업(표본I, II)만을 대상으로 이익조정과 보수주의에 대한 직접적인 관계를 분석한 결과, 유의한 양(+)의 결과가 나타났는데, 이는 적자회피 기업의 보수주의수준이 통제기업에 비해 낮을지라도 이들 기업들의 투자자 및 채권자들은 높은 발생액에 따른 대리비용을 고려하여 기업으로 하여금 보수주의를 강화하도록 요구하게 되고, 기업은 투자자 및 채권자의 요구를 반영한 결과일 수 있다.