• 제목/요약/키워드: actual size test

검색결과 255건 처리시간 0.023초

고장력강 용접부에 있어서 한계 COD값과 V charpy충격치와의 상관성에 관한 연구 (A study on the correlation between V charpy absorbed energy and critical COD value in the welded parts of high tensil strength steel under various welding methods)

  • 김영식;김충해
    • Journal of Advanced Marine Engineering and Technology
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    • 제12권3호
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    • pp.57-67
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    • 1988
  • Although handicapped by the inability to bridge the size gap between small laboratory sample and large engineering component, the V charpy test sample method does possess certain advantages, such as each of preparation, simplicity of test method, speed, low cost in test machinery, and low cost per test. On the other hand, the COD test method does posses advantages, which reduce the size gap between the laboratory sample and actual engineering component. Consequently, the correlation between V charpy absorbed energy and the critical COD value is required for estimating critical COD value from the simple V charpy test results. In this paper, the high tensile strength steel AH36 plate specimens having a single edge cracked notch were investigated to find out the correlation between V charpy absorbed energy and critical COD value in the welded parts under such various welding methods as shielded metal arc welding, the submerged arc welding and the electro gas welding by means of V charpy impact test and static 3-point bending test. Main results obtained are as follow ; 1. The relationships between V charpy absorbed energy Wc' and critical COD value ($\delta_c$)show; $\delta_c$=0.0065 Wc'+0.1906. 2. Ductile- brittle transition behaviours can be estimated by means of fracture appearance and general yielding behaviours. 3. The V charpy absorbed energy of SMAW is higher than that of SAW, EGW and similar relationships are obtained in the COD tests.

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건축용 비내력 경량벽체의 내충격성 시험방법의 표준화 (Standardization of Impact Test Methods of Non-bearing Lightweight Wall for Building)

  • 김기준;최수경
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.181-182
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    • 2015
  • The use of non-bearing light weight wall has increased recently due to the increase of high-rise buildings and supply of long-life housing. Light weight wall has advantages such as reducing the self-weight of the building, convenience in installation, and shortening construction period, however, must have a sufficient strength to external force. This study standardized the impact resistance test method for light weight walls by using the actual impact load obtained through load analysis test in previous studies. The impact resistance test method was divided into the test method that uses soft body and the one that uses hard body. The size of specimen was set up as height 2.4m and width 3.0m. The size and shape of the body followed those used in BS 5234-2 and so on for the compatibility with the test method used overseas. The judgment criteria for impact resistance based on test results were not defined uniformly as the assessment of functional damage can vary depending on the type of material, structural method, purpose of wall, and so on even when the same impact load was applied.

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기계적 협착부를 갖는 근관에서 Root-ZX의 정확도에 관한 연구 (A STUDY ON THE ACCURACY OF THE ROOT-ZX IN THE CANAL WITH MECHANICALLY FORMED CONSTRICTION)

  • 김병현;이영규;김용식
    • Restorative Dentistry and Endodontics
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    • 제24권4호
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    • pp.628-632
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    • 1999
  • Currently electronic apex locators have been widely used to determine working length in endodontic treatment. According to Manufacture's recommendation, it is beneficial to find the working length before instrumenting the canal. However, in crown-down pressureless technique, working length of tooth is established following coronal instrumentation 3mm short of radiographic apex. In narrow canals, mechanically formed constriction might be established by coronal instrumentation in some distance from anatomical constriction. The purpose of this study was to evaluate the accuracy of Root-ZX in the canal with mechanical constriction following considerable coronal enlargement with ProFile .06 series. The 40 root canals in 30 extracted mandibular molars were accessed, and their actual length (AL) established by passing a size 10 file just through the minor apical foramen. The teeth were then embedded in an acrylic container with normal saline. The initial canal length(IL) was measured with Root-ZX by negotiating a size 10 file to the apical constriction. The canal was sequentially enlarged to size 40 with ProFile .06 file 3mm short of actual length. The enlarged final canal lengths (FL) were obtained with a size 15 file. The average values of IL, FL were calculated and compared using Repeated measures Analysis of Variance followed Turkey's Studentized Range test. The results were obtained as follows: 1. The initial canal length was 0.12mm shorter than actual canal length(P>0.05). 2. The differences between initial canal length and final canal length were not significant(P>0.05). 3. As a result of this study, regardless of mechanically formed constriction. Root-ZX differentiated between mechanical and anatomic constriction.

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중년여성 기성복 하의의 착용실태 및 맞음새에 관한 연구 -만 34세에서 59세까지- (A Study on the Actual Wearing Conditions and Fit Preferences of the Middle-Aged Women's Ready-to-Wear Lower Body Clothing - For women aged 34 to 59-)

  • 김은경;최혜선;이경미
    • 대한가정학회지
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    • 제41권3호
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    • pp.1-15
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    • 2003
  • This study was conducted to analyze the actual wearing conditions and body fit preferences of the middle-aged women's ready-to-wear lower body clothing. The aim was also to analyze lower body recognition, lower body satisfaction, fit preferences and size satisfaction according to age and degree of girth size. A questionnaire was developed and administered to 300 middle-aged women aged 34 to 59. Statistical tests such as descriptive analysis, crosstabs, and X²-tests were conducted to analyze the data and ascertain the differences between the ages. Lower body satisfaction and recognition were compared by T-test. Also, Anova was used to analyze lower body recognition, satisfaction, fit preferences, and size satisfaction according to age and degrees of girth size. The results indicated that women aged 50 to 59 were more dissatisfied with the ready-to-wear sizing system and because of their body shapes had changed, their need for a larger size range system had also increased. Moreover, the element that most affected their purchase of ready-to-wear lower body clothing was the design followed by the size. The women, especially of the ages 50 to 59, showed a tendency to he dissatisfied with their lower bodies and they recognized that their lower bodies had thickened compared to women aged 34 to 39 and 40 to 49. Analysis of body satisfaction, recognition, and fit preference according to girth size showed that the group of larger girth size recognized that their lower bodies were thicker and were more dissatisfied and preferred looser fittings than the groups of smaller women.

Numerical study on Jarque-Bera normality test for innovations of ARMA-GARCH models

  • Lee, Tae-Wook
    • Journal of the Korean Data and Information Science Society
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    • 제20권2호
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    • pp.453-458
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    • 2009
  • In this paper, we consider Jarque-Bera (JB) normality test for the innovations of ARMA-GARCH models. In financial applications, JB test based on the residuals are routinely used for the normality of ARMA-GARCH innovations without a justification. However, the validity of JB test should be justified in advance of the actual practice (Lee et al., 2009). Through the simulation study, it is found that the validity of JB test depends on the shape of test statistic. Specifically, when the constant term is involved in ARMA model, a certain type of residual based JB test produces severe size distortions.

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성인여성(成人女性)의 연령별(年齡別) 파운데이션 착용실태 연구(着用失態 硏究) - 브래지어와 거들을 중심(中心)으로 - (A Study on the Actual Wearing Condition of Foundation Garment for Adult Women - Focusing on the Brassiere and Girdle -)

  • 김영숙
    • 패션비즈니스
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    • 제10권1호
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    • pp.132-147
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    • 2006
  • The purpose of this study is to provide for the basic data useful to the effective production and marketing of the foundation garment befitting adult women's shapes and preferences, and thereby, help them improve their apparel life. For this purpose, 563 Korean women aged between 20-59 were sampled to survey their recognition and actual wearing condition of foundation garments and positively identify the factors affecting the practices and thereupon, determine the correlations among them by age group. The raw data of this study is processed by SPSS Win(10.1) and analyzed by using frequency, percentage, $x^2$-test, ANOVA, Duncan-test. The most of adult women were aware of their foundation size and the absolute majority of them wore brassieres, while a half of them used the girdles. The adult women had 5.7 Brassieres and 2.2 Girdles. The use of the foundation depended much on user's age or seasons. They had begun to wear Brassieres at their age of 15 on an average and Girdle around their age of 19 depending their individual needs. It has been found through this study that adult women's is actual wearing condition of foundation garments differ by age group, which may well suggest that foundation production need to consideration this age-wise practices when setting up their foundation production and marketing strategies.

Numerical analysis on Deformation of Seabed Structures with various size materials by DEM

  • Kim, Mi-Kum;Kim, Chang-Je
    • 한국항해항만학회지
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    • 제31권7호
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    • pp.589-595
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    • 2007
  • In the majority of previous studies on deformation of seabed structures using DEM, elements of structures have been assumed that it is composed with uniform materials or received fixed wave force, despite that actual submerged structures are composed with various size materials and influenced by complicated fluid field. The goal of this study is to develop a new model for analysis of seabed structure deformation using discontinuous structures composed with various size materials. As the first phase, a model using DEM and VOF, which can compute the deformation of submerged structures composed with various size materials, such as rubble mound structures, is proposed. A model test is carried out and then the validity of the model is discussed.

인공신경회로망을 이용한 저항 점용접의 품질감시 (The Use of Artificial Neural Networks in the Monitoring of Spot Weld Quality)

  • 임태균;조형석;장희석
    • Journal of Welding and Joining
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    • 제11권2호
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    • pp.27-41
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    • 1993
  • The estimation of nugget sizes was attempted by utilizing the artificial neural networks method. Artificial neural networks is a highly simplified model of the biological nervous system. Artificial neural networks is composed of a large number of elemental processors connected like biological neurons. Although the elemental processors have only simple computation functions, because they are connected massively, they can describe any complex functional relationship between an input-output pair in an autonomous manner. The electrode head movement signal, which is a good indicator of corresponding nugget size was determined by measuring the each test specimen. The sampled electrode movement data and the corresponding nugget sizes were fed into the artificial neural networks as input-output pairs to train the networks. In the training phase for the networks, the artificial neural networks constructs a fuctional relationship between the input-output pairs autonomusly by adjusting the set of weights. In the production(estimation) phase when new inputs are sampled and presented, the artificial neural networks produces appropriate outputs(the estimates of the nugget size) based upon the transfer characteristics learned during the training mode. Experimental verification of the proposed estimation method using artificial neural networks was done by actual destructive testing of welds. The predicted result by the artifficial neural networks were found to be in a good agreement with the actual nugget size. The results are quite promising in that the real-time estimation of the invisible nugget size can be achieved by analyzing the process variable without any conventional destructive testing of welds.

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황토미장재 성능개선을 위한 실험적 연구 (A fundamental Study on the Performance Improvement of Hwangto plaster)

  • 황혜주;이종국;강남이
    • KIEAE Journal
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    • 제5권3호
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    • pp.49-56
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    • 2005
  • Recently the Volatile Organic Compound, HCHO, a harmful object spout from the construction materials is made an issue of social problem. Also the appearance of the building where the confidentiality is high was interior air pollution and it was brought about a huge problem. The government research facility and a relation industry sector conducts a many effort to improves like this actual condition. The Diverse ability building material which contains the natural material of the jade, the charcoal and the hwangto instead of the finish material which contains the harmful chemical material, is becoming development and utility. Hereupon the study have carried out research on hwangto plaster that was composed of hwangto and rice straw. The result of test that is deduced by basic proportion is properly appeared with suitable ratio of the hwangto and the sand to 4:6~5:5 by the compressive strength and crack control, workability. The result of test, that adds the rice straw to basic blending for a crack control, appeared with the fact that it is most suitable 3%to add the rice straw that has a length of 0.5cm~2cm. The result of test that plaster over the large size to compare a cement plaster with a hwangto plaster show a similar efficiency by workability. Also it controlled the crack and peeling off actual condition which is discovered from the hwangto plaster of existing perfectly.

소형 풍동을 이용한 토양의 풍식 가능 입경 분석 (Experimental Investigation on Particle Size of Soils Erodible by Wind using Portable Wind Erosion Tunnel)

  • 김태완;손영환;민슬기;이인복;홍세운;김민영
    • 한국농공학회논문집
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    • 제55권6호
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    • pp.127-133
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    • 2013
  • The purpose of this study was to investigate maximum and minimum grain size which eroded by wind according to soil and wind conditions, such as top soil water content, roughness, land slope, wind velocity and proportion of grain size under 0.84mm. For performing this study, portable wind erosion tunnel was designed and utilized during field test, which facilitated measuring actual wind erosions under artificially controlled wind conditions. In the result, maximum, minimum grain size had strong negative correlation with roughness while weak positive correlation with wind velocity. Also, Slope which means the effect of gravity also influence grain size erodible by winds. Based on these results, regression equations were suggested for predicting maximum and minimum grain sizes by using multiple linear regression analysis from SPSS 20.0. The equation for maximum grain size erodible by winds showed a good agreement with the observed data with $R^2$=0.896. Other equation for minimum grain size had $R^2$=0.777.