• Title/Summary/Keyword: conservativeness

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A Study on the Behavior of High-rise Buildings Considering Soil-Structure Interaction (지반-구조물 상호작용을 고려한 고층 구조물의 거동에 관한 연구)

  • Kim, Se-Hyun;Park, Sung-Soo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.4
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    • pp.243-251
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    • 2005
  • In the seismic design the pile foundation system of the buildings generally have been modeled to have a fixed end for its convenience and conservativeness. But it is necessary to consider the soil-structure interaction for more reliable design. In this study, the framed tube building and brace tube building with pile foundation system under earthquake were analyzed considering soil-structural interaction by 3 pile foundation modeling methods; fixed-end model, 6 springs model and p-y springs model. And 2 soil conditions were used in analysis. For each cases, displacements, drifts, maximum stress, periods and 1st mode mass participation ratios were compared.

Environmental Fatigue Evaluation for Thermal Stratification Piping of Nuclear Power Plants (열성층을 포함하는 원자력발전소 배관의 환경피로평가)

  • Kim, Taesoon;Kim, Kyuhyung
    • Journal of the Korean Society of Safety
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    • v.33 no.5
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    • pp.164-169
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    • 2018
  • A detailed fatigue evaluation procedure was developed to mitigate the excessive conservativeness of the conventional environmental fatigue evaluation method for the pressurizer spray line elbow of domestic new nuclear power plants. The pressurizer spray line is made of austenitic stainless steel, which is relatively sensitive to the environmentally assisted fatigue, and has a low degree of design margin in terms of environmentally assisted fatigue due to the thermal stratification phenomenon on the pipe cross section as a whole or locally. In this study, to meet the environmental fatigue design requirements of the pressurizer spray line elbow, the new environmental fatigue evaluation has been performed, which used the ASME Code NB-3200-based detailed fatigue analysis and the environmental fatigue correction factor instead of the existing NB-3600 evaluation method. As a result, the design requirements for environmentally assisted fatigue were met in all parts of the pressurizer spray line elbow including the fatigue weakened zones by thermal stratification.

The Impact of Lifestyle Factors on Clothing Purchase Motives, Information Use, and Selection Criteria in Male College Students (남자대학생의 라이프 스타일 요인이 의복의 구매동기, 정보원활용, 의복선택기준에 미치는 영향 연구)

  • 황진숙;이기춘
    • Journal of the Korean Society of Costume
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    • v.50 no.4
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    • pp.63-72
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    • 2000
  • The purpose of this study was to investigate the effects of lifestyle factors on clothing purchase motives, information use, and selection criteria in male college students. The sample included 241 male college students, and an instrument was developed based on the previous studies. The statistical analyses used for this study were factor analysis and multiple regression. The result of factor analysis showed that lifestyle consisted of six factors : clothing interest, serif-confidence, social participation, planned clothing purchase, family-orientation, and conservativeness. Clothing purchase motives consisted of conspicuous consumption motives, fashion and individuality motives, and economic motives. Clothing information use consisted of four factors: paper/display, personal advice, fashion show/clothing observation, and electronic media. Finally. clothing selection criteria consisted of practicability, fashion/individuality, and conformity, Multip1e regression revealed that there were significant effects of lifestyle factors on clothing purchase motives, information use, and selection criteria. For example, self-confidence factor had a negative impact on conspicuous consumption motive, personal advice information use, and fashion/individuality criteria. The relative importance of lifestyle factors were different according to different dimensions of clothing purchase motives, information use, and selection criteria.

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Development of Wall-Thinning Evaluation Procedure for Nuclear Power Plant Piping-Part 1: Quantification of Thickness Measurement Deviation

  • Yun, Hun;Moon, Seung-Jae;Oh, Young-Jin
    • Nuclear Engineering and Technology
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    • v.48 no.3
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    • pp.820-830
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    • 2016
  • Pipe wall thinning by flow-accelerated corrosion and various types of erosion is a significant and costly damage phenomenon in secondary piping systems of nuclear power plants (NPPs). Most NPPs have management programs to ensure pipe integrity due to wall thinning that includes periodic measurements for pipe wall thicknesses using nondestructive evaluation techniques. Numerous measurements using ultrasonic tests (UTs; one of the nondestructive evaluation technologies) have been performed during scheduled outages in NPPs. Using the thickness measurement data, wall thinning rates of each component are determined conservatively according to several evaluation methods developed by the United States Electric Power Research Institute. However, little is known about the conservativeness or reliability of the evaluation methods because of a lack of understanding of the measurement error. In this study, quantitative models for UT thickness measurement deviations of nuclear pipes and fittings were developed as the first step for establishing an optimized thinning evaluation procedure considering measurement error. In order to understand the characteristics of UT thickness measurement errors of nuclear pipes and fittings, round robin test results, which were obtained by previous researchers under laboratory conditions, were analyzed. Then, based on a large dataset of actual plant data from four NPPs, a quantitative model for UT thickness measurement deviation is proposed for plant conditions.

A new strain-based criterion for evaluating tunnel stability

  • Daraei, Ako;Zare, Shokrollah
    • Geomechanics and Engineering
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    • v.16 no.2
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    • pp.205-215
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    • 2018
  • Strain-based criteria are known as a direct method in determining the stability of the geomechanical structures. In spite of the widely use of Sakurai critical strain criterion, it is so conservative to make use of them in rocks with initial plastic deformation on account of the considerable difference between the failure and critical strains. In this study, a new criterion has been developed on the basis of the failure strain to attain more reasonable results in determining the stability status of the tunnels excavated in the rocks mostly characterized by plastic-elastic/plastic behavior. Firstly, the stress-strain curve was obtained having conducted uniaxial compression strength tests on 91 samples of eight rock types. Then, the initial plastic deformation was omitted making use of axis translation technique and the criterion was presented allowing for the modified secant modulus and by use of the failure strain. The results depicted that the use of failure strain criterion in such rocks not only decreases the conservativeness of the critical strain criterion up to 42%, but also it determines the stability status of the tunnel more accurately.

A Study on the Perfume Purchasing and Using Behavior According to Men's Fashion Lifestyle (남성들의 패션 라이프스타일에 따른 향수 구매 및 사용행동)

  • Kim, Yong-Sook
    • Korean Journal of Human Ecology
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    • v.18 no.4
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    • pp.933-944
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    • 2009
  • The purposes of this study was to identify perfume purchasing and using behavior according to men's fashion lifestyle. Self-administered questionnaires were used for data collection. The subjects were 317 men aged 19-40. The results were as follows: First, over half of men had purchased at least one perfume during last year and the price was 30,000-60,000won. Men selected perfumes which harmonized with their image or purposes of using perfumes. Men selected a perfume as a present for their girl friends or wives to convey their concern or love. Most men purchased perfumes at department stores and selected after experiencing samples, and by affecting advertisements of newspapers or journals. Over 60% of men possessed at least one perfume and most of them were imported perfumes. Most men used perfume on a special day such as dates or job interviews, and they received perfume as a gift from their girl friends or wives. Most men used perfumes to enjoy fragrances by themselves and preferred sea fragrance most. Second, factors of men's fashion lifestyle were fashion information, individuality, conservativeness, ostentation, activity, and fashion style. Men were segmented into ostentatious consumption group, active group, fashion leader group, and fashion retard group. Third, fashion leader group purchased perfumes more than other groups and fashion retard group purchased the least.

A Study on the symbol of the Korean Beak Eui (한국의 백의상징에 관한 연구)

  • 류은희
    • Journal of the Korean Society of Costume
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    • v.20
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    • pp.93-104
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    • 1993
  • The purpose of this study is to clarify the adap-tation of traditional beauty of dress in Baek Eui for the establishment of tradition of dress culture. Especially, the color of the traditional dress rep-resent a symbol which is connedted with the na-tional character and the evvironment. But it is hard to examine closely because color preference are transformend with the times. This study is framed within the limits of the next themes : the origin, history and meaning of the Baek Eui ; the philosophical theory of cosmic Five Elements and the Prohibition of Baek Eui ; the beauty of Baek Eui. As the national character is indicative of the conservativeness and the purity, Koreans have kept up wearing Baek Eui spite of the occasional prohibition. Since the color of the dress represen-tatived the signs of the social class and the power, over the eighty persent of the common people put on the Beak Eui : ramie and flax fabrics that has it's own color in Chosun-Dynasty. I think that the use of natural color harmony is prominent and the beauty of Baek Eui is the naturality and the non-artificiality. The meaning of the symbol on the Korean Beak Eui is the divinity, the holiness, the purity, the cleanliness, the modesty, the frugality, the integ-rity, the constancy, the elegance, the simplicity.

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A Study on the Evaluation of the Pipe Fracture Characteristic (I) (실배관 파괴특성 평가에 관한 연구 (I))

  • Park, Jae-Sil;Seok, Chang-Sung
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.345-350
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    • 2001
  • In order to perform elastic-plastic fracture mechanical analyses, fracture resistance curves for concerned materials are required. 1T-CT specimen was used to obtain fracture resistance curves. But the fracture resistance curve by the 1T-CT specimen was very conservative to evaluate the integrity of the structure. And fracture resistance curve was affected by the specimen geometry and crack plane orientation. The objective of this paper is to be certain the conservativeness of the fracture resistance curve by the 1T-CT specimen and to provide the additional safety margin. For these, the fracture tests using the real pipe specimen and standard 1T-CT specimen test were performed. 4-point bending jig was manufactured for pipe test and direct current potential drop method was used to measure the crack extension and length for pipe test. From the pipe and the 1T-CT specimen test results, it was observed that the J-integral of the 1T-CT specimen test at the crack initiation point was very small compare to that of the pipe specimen test.

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Studies on the Reinforcement Treatment of Aged Hanji Using Cellulose Derivative Solutions (셀룰로오스 유도체 용액을 이용한 열화 한지의 강도보강 처리에 관한 연구)

  • Kang, Kwang-Ho;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.2
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    • pp.40-48
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    • 2011
  • To build up the conservativeness of aged paper heritages, the strength reinforcement treatment using various cellulose derivative solutions was considered. Hand-made Hanji prepared by traditional papermaking technique was firstly simulated in order to modify the overall of paper properties like aged paper heritages by accelerated ageing treatment at $150^{\circ}C$ for 24 hours, and then the ageing stability of Hanji was verified through the secondary accelerated ageing at $150^{\circ}C$ for 12 hours. The physical properties of aged Hanji were improved by applying with cellulose derivative solutions. The ageing stability for physical, optical (L, brightness, opacity, yellowness) and chemical (oxidation index, degree of polymerization) properties of aged Hanji treated with all kinds of cellulose derivative solutions was also good compared to those of untreated samples, especially using MC solution. Therefore, it was that a kind of MC solution would be well-suited for the strength reinforcement treatment of aged paper heritages.

Design of the Robust Fuzzy Controller based on Fuzzy Lyapunov Functions (퍼지 리아푸노프 함수 기반 강인한 퍼지 제어기 설계)

  • Kim, Ho-Jun;Park, Jin-Bae;Joo, Young-Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.5
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    • pp.630-636
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    • 2011
  • This paper is concerned with the stability analysis and stabilization for the Takagi-Sugeno(T-S) fuzzy systems with parametric uncertainties. To reduce conservativeness in stability analysis for T-S fuzzy systems, fuzzy Lyapunov functions are used. Stability analysis is performed and robust fuzzy controller is designed for stabilization of the system with parametric uncertainties. The stability and stabilization conditions are formulated in terms of linear matrix inequalities (LMIs). Finally, simulation example is presented to show the effectiveness of the proposed approach.