• 제목/요약/키워드: Factor Weight

검색결과 3,389건 처리시간 0.035초

가중함수법을 적용한 파이프라인 구조건전성평가에 관한 연구 (A Study on Structural Integrity Assessment of Pipeline using Weight Function Solution)

  • 노기섭;오동진;김명현
    • Journal of Welding and Joining
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    • 제35권1호
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    • pp.55-60
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    • 2017
  • There are many Industry Code and Standard (ICS) for Structural Integrity Assessment (SIA) on welded structure with defect. The general ICSs, such as R6, BS 7910 and API 579-1/ASME FFS-1, provide equations to determine the upper bound residual stress profiles based on collections from many literatures. However, these residual stress profiles used in the SIA cause the conservative design for welded structures. In this study, the structural integrity assessment for girth weld in pipeline has been conducted based on fracture mechanics. In addition, thermo-elastic plastic FE analysis was performed for evaluating the residual stress of girth weld in pipeline. The weight function solution is used to determine the stress intensity factor using the residual stress profile obtained by the FE analysis. This approach can account for redistribution and relaxation of residual stress as the defects grow. In order to the evaluate quantitative comparison between BS 7910 and weight function solution, structural integrity assessment determining allowable crack size on cracked pipe was performed with failure assessment diagram.

AHP를 이용한 전력설비 입지선정 항목 중요도 분석 (Analysis of Weight Factors for Siting the Electric Facilities utilizing Analytical Hierarchy Process)

  • 구자건;김상호;윤고산;강현재;정종철
    • 환경영향평가
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    • 제21권3호
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    • pp.381-389
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    • 2012
  • This study was conducted to analyze the weight factors for siting the electric facilities using Analytic Heirarchy Process technique participating the stakeholders. Siting the electric facilities has been a dispute of long standing because of landscape damage, geological deformation and various environmental problems such as electromagnetic effect to human health. For analyzing the weight factors by AHP technique, the questionnaire process was applied to the fifteen committee members including representatives of resident, academic experts, members of local assembly, officers of local government, journalists, etc. in Gangwondo, Korea. Weight factors for siting the electric facilities by AHP committee members resulted in residential areas 35.06%, cultural assets 16.68%, landscape conservation 13.11%, large-scale ecological corridor 10.17%, connectability of electric transmission line 8.32% respectively. The distance from residential areas was the most important factor preferred by committee members for siting the electric facilities.

도심 친수공간 적지선정을 위한 평가기준의 가중치 산정방법 개발 (Development of a method for calculating weights of evaluation criteria for proper selection of urban waterfronts)

  • 김성만;이재춘;박민정;권재범;이용운
    • 환경영향평가
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    • 제21권5호
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    • pp.683-693
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    • 2012
  • The urban waterfront well created, could provide mental stability and comfort and also foster personality. In addition it could provide the calmness and rest of mind. Especially, recently the urban waterfronts are restored here and there and are created whenever developing a new town The purpose of this study is to develop a method of calculating the weight of each evaluation criterion for deciding the priority of restoration among for deciding the priority of restoration among the urban waterfronts. The method includes the analytic hierarchy process that can calculate the reasonable weight of each evaluation criterion, because the importance (weights) of evaluation criteria appears to be different among the evaluators; the results of this study can be summarized as that this method can be useful for calculating the weights of evaluation criteria, and also that the superiority of ecological resources is the most important factor (highest weight) in selecting the best waterfront, followed by accessibility, tourism vacation, and proximity to parks. And then the lowest factor in importance is the scale of reservoir.

초등학생의 비만 관련 요인에 관한 연구 - 정상군과 비만군을 중심으로 - (A Study on Related Risk Factors of Obesity for Primary School Children - Difference between Normal and Obese Group -)

  • 박미아;문현경;이규한;서성제
    • Journal of Nutrition and Health
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    • 제31권7호
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    • pp.1158-1164
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    • 1998
  • This study was carried out to provide information on the related factors for child obesity through investigation of children aged 6-12. Data was obtained on family history, dietary habits and physical examinations. Children were classified into normal(98 persons) and obese (108 persons) groups using combinations of the height f3r age, weight fir age, and weight fir height standards used by the World Health Organization. Children's height, weight and BMI showed significant differences between groups except children aged 8 for height. Birth weight, breast feeding and unbalanced diet were not associated with obesity. Overeating was a risk factor in the obese group(Odd ratio : 3.417, 95% CI 1.879-6.212). Taking nutrition pills was correlated to obesity. Odd ratio for taking nutrition pills was 0.109(95% CI : 0.024-0.492) between normal and obese group. Number of brothers didn't have any correlation to obesity. Obesity was not correlated to mother's education level or employmental status. As the result of this study, children's obesity was related to overeating and taking nutrition pills. Therefore, these results suggest that systematic dietary education and continuous parental supervision are necessary to avoid child obesity. (Korean J Nutrition 31(7) : 1158-1164, 1998)

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위상최적설계를 활용한 압출기의 플라텐 경량화 설계 (Platen Weight Reduction Design of Extruder Using Topology Optimization Design)

  • 김동율;김지욱;이정인;조아라;이성윤;정명식;고대철;장진석
    • 소성∙가공
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    • 제31권5호
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    • pp.302-308
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    • 2022
  • In this study, the weight of the platen was reduced using the structural strength analysis and topology optimization design of the extruder by finite element analysis. The main components of the extruder such as the stem and billet, were modeled, and the maximum stress and safety factor were verified through structural strength analysis. Based on the results of the structural strength analysis, the optimal phase that satisfies the limitation given to the design area of the structure and maximizes or minimizes the objective function was obtained through a numerical method. The platen was redesigned with a phase-optimal shape, the weight was reduced by 40% (from the initial weight of 11.1 tons to 6.6 tons), and the maximum stress was 147.49 MPa safety factor of 1.86.

Polymorphism of Insulin-like Growth Factor Binding Protein-4 Gene in 17 Pig Breeds and Its Relationship with Growth Traits

  • Wang, Wenjun;Hu, Xiaoxiang;Fei, Jin;Meng, Qinyong;Li, Ning
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권10호
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    • pp.1490-1495
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    • 2007
  • Insulin-like growth factor binding protein-4 (IGFBP-4) is a member of the IGF super family, and regulates the action of IGFs. The polymorphism of porcine IGFBP-4 gene in 17 pig breeds (total n = 570) was detected by PCR-SSCP, and alleles A and B were detected. In these pig breeds, it was found that exotic pig breeds carried high frequencies of allele A, while Chinese native pig breeds carried high frequencies of allele B. The role of porcine IGFBP-4 was investigated in 172 F2 offspring of a $Lantang{\times}Lantang $ population. Forty eight growth traits were recorded for analyzing the association between IGFBP-4 gene polymorphism and quantitative performance traits. In this resource family, pigs with AA genotype had higher fore-body weight, bone weight of mid-body, bone weight of rear-body, fore-leg weight and rear-leg weight than those pigs with BB genotype (p<0.05); while pigs which carried BB genotype had higher back-fat thickness at C point and lard weight than those pigs with AA genotype (p<0.05); pigs with AA genotype had higher body weight than those with BB genotype; for meat quality traits, pigs with AA genotype had higher meat color than those of BB genotype (p<0.01), and pigs with BB genotype had higher marbling than those of AA and AB genotypes (p<0.01 and p<0.05, respectively).Based on these results, it is necessary to do more studies on IGFBP-4 before using the IGFBP-4 locus for the application of marker-assisted selection programs.

인공신경 망을 이용한 산사태 발생요인의 가중치 결정 (Weight Determination of Landslide Factors Using Artificial Neural Networks)

  • 류주형;이사로;원중선
    • 자원환경지질
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    • 제35권1호
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    • pp.67-74
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    • 2002
  • 본 연구의 목적은 산사태 취약성 분석을 위하여 인공신경망을 이용하여 산사태 요인의 가중치를 결정하는 것이다. 산사태 발생 지역은 항공사진, 현장조사와 지형도 등으로부터 위치를 파악하였다. 용인 지역에 대해서 산사태에 영향을 주는 지형경사, 지형곡률, 토양배수, 토양 유효심도, 토양 종류, 식생 경급과 영급 등의 자료가 사용되었다. 이들 자료를 이용하여 인공신경망의 층간 가중치가 역전파 트레이닝 알고리즘에 의해 계산되었으며, 이는 산사태 요인의 가중치를 결정하는데 사용되었다. 죽, 트레이닝 후 층간 가중치를 해석하여 분류에 미치는 영향을 고려함으로서 각 산사태 요인의 가중치가 결정되게 된다. 가장 높은 값은 지형경사로서 5.33의 값을 나타냈으며 지형 곡률과 토질은 각각 1과 1.17로 낮은 값을 나타냈다. 역전파 알고리즘을 이용한 가중치 결정 방법은 분석에 중요하지 않은 요인을 제거함으로 계산시간을 단축시킬 수 있어 GIS를 이용한 중첩 분석 연구에 활용되 수 있다.

중량체 적용을 통한 계류선의 설계개선 방안 연구 (Improved design for mooring line with lumped weight at seabed)

  • 송제하;신승호;정동호;김현주
    • 한국해양공학회지
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    • 제27권6호
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    • pp.22-26
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    • 2013
  • The purpose of this study was to improve the design of a mooring line by attaching a lumped mass to it on the seabed. A numerical analysis of the redesigned mooring system is performed to analyze the effect of the weight of the attached lumped mass using the commercial software Orcaflex. The ultimate tension of the mooring system with the lumped mass is compared with that of a bare mooring line in the original design. An appropriately designed weight for the lumped mass is found to induce a critical lifted point in the mooring line by floater motion in the ultimate condition to move toward the floater position from the anchor point, while maintaining a similar safety factor for the mooring line. On the other hand, it is shown that excess weight for the lumped mass induces snapping in a mooring line, resulting in low safety factor for the mooring system. The distance between lumped weights is shown to be a minor parameter affecting the safety of a mooring line, although a shorter line has an advantage from an economic point of view. Using the optimal weight for the lumped mass attached to the mooring line on a seabed reduces the mooring line length and installation area occupied by a mooring system under real sea conditions.

대학생들의 건강관련 요인이 커피와 전통음료의 기호도와 섭취빈도에 미치는 영향 (The Preference and Frequency of Beverages related to Health Factor in University Students)

  • 신선영;정라나
    • 한국식생활문화학회지
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    • 제22권4호
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    • pp.420-433
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    • 2007
  • This study was performed to investigate the effect of the health related factors on the preference and frequency of intake of coffee and traditional beverages among 280 university students (128 males and 152 females) who were residing in Incheon areas. The results were as follows; 1. Male students of over weight and obese were more than female students and female students of under weight were more than male students. Female students were interested in weight control and had an experience in weight control more than male students. 2. The group who was much interested in weight control preferred green tea, yuja tea and dunggulre tea. The group who was much interested in health when drink beverages preferred green tea, ginseng tea, dunggulre tea, vinegar drinks and water but didn’t prefer coffee. 3. The frequency of intake of green tea is high in the group who had an experience in weight control. And the frequency of intake of honey tea was high in the group who drank alcohol almost every day. Coffee intake was the highest among beverages in smokers and water intake was the highest among beverages in nonsmokers. In conclusion this study showed that as an interest in health is higher, the preference and frequency of intake of coffee was low whereas those who intake of traditional beverages was high in general.

A study on modeling and measuring method of tire weight imbalances and improving reliability (ICCAS 2004)

  • Lee, Ki-Seong;Jeong, Tae-Woon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.1685-1688
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    • 2004
  • I propose a modeling of a mechanism for weight fire uniformity measurement of a tire and a way I interpret a Sampling signal by Loadcell through an analysis, and to measure fire uniformity in this study. Correct a weight fire uniformity measurement was possible through the production of conversion and influence factor of a signal with a basis with the model who was an oscillation mechanics enemy.

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