• Title/Summary/Keyword: BIG4

Search Result 3,614, Processing Time 0.031 seconds

A study on the Effects of Input Parameters on Springback Prediction Accuracy (스프링백 해석 정도 향상을 위한 입력조건에 관한 연구)

  • Han, Y.S.;Oh, S.W.;Choi, K.Y.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2007.05a
    • /
    • pp.285-288
    • /
    • 2007
  • The use of commercial finite element analysis software to perform the entire process analysis and springback analysis has increased fast for last decade. Pamstamp2G is one of commercial software to be used widely in the world but it has still not been perfected in the springback prediction accuracy. We must select the combination of input parameters for the highest springback prediction accuracy in Pamstamp2G because springback prediction accuracy is sensitive to input parameters. Then we study the affect of input parameters to use member part for acquiring high springback prediction accuracy in Pamstamp2G. First, we choose important four parameters which are adaptive mesh level at drawing stage and cam flange stage, Gauss integration point number through the thickness and cam offset on basis of experiment. Second, we make a orthogonal array table L82[(7)] which is consist of 8 cases to be combined 4 input parameters, compare to tryout result and select main factors after analyzing affect factors of input parameters by Taguchi's method in 6 sigma. Third, we simulate after changing more detail the conditions of parameters to have big affect. At last, we find the best combination of input parameters for the highest springback prediction accuracy in Pamstamp2G. The results of the study provide the selection of input parameters to Pamstamp2G users who want to Increase the springback prediction accuracy.

  • PDF

A Study on Plate Waste and Nutrient Intake of School Lunches in Elementary School (초등학교급식에서 제공된 음식의 잔식량과 영양섭취 실태에 관한 연구)

  • Kim, June;Ko, Sung-Hee;Kim, Ji-Young;Kim, Heh-Young
    • Journal of the Korean Society of Food Culture
    • /
    • v.15 no.1
    • /
    • pp.29-40
    • /
    • 2000
  • The purposes of this study were to (a) measure plate waste of school lunches, (b) evaluate the nutrients actually consumed by students in elementary school foodservice. The survey was conducted between May 11 and July 1, 1998 through the practical measurement and questionnaires. Statistical data analysis was completed using SAS program for descriptive analysis and T-test. The results were summarized as follows: 1. The mean plate waste of menu group were soup, vegetable side dishes, kimchi, and meat side dish in order. 2. There was little difference between estimation and weighing of plate waste. 3. The satisfaction of children with school lunches were significantly higher for boys(73.55%) than for girls(71.13%). The highest level of the satisfaction was meat side dishes among boys and girls. 4. The majority reasons for leaving leftover were 'too big portion' and 'food is not tasty'. 5. There was significant negative correlation between plate waste and student's satisfaction. In summary, increased satisfaction with school lunches in most menus resulted in decreased plate waste rate. 6. Comparison of $\frac{1}{3}$ RDA, energy, vitamin A and calcium were below recommended allowances for boys while energy vitamin A, calcium and iron were for girls. In general, the nutrient intake was more adequate for boys than girls because of the girl's lower allowances.

  • PDF

Time-lapse Inversion of 2D Resistivity Monitoring Data (2차원 전기비저항 모니터링 자료의 시간경과 역산)

  • Kim, Ki-Ju;Cho, In-Ky;Jeoung, Jae-Hyeung
    • Geophysics and Geophysical Exploration
    • /
    • v.11 no.4
    • /
    • pp.326-334
    • /
    • 2008
  • The resistivity method has been used to image the electrical properties of the subsurface. Especially, this method has become suitable for monitoring since data could be rapidly and automatically acquired. In this study, we developed a time-lapse inversion algorithm for the interpretation of resistivity monitoring data. The developed inversion algorithm imposes a big penalty on the model parameter with small change, while a minimal penalty on the model parameter with large change compared to the reference model. Through the numerical experiments, we can ensure that the time-lapse inversion result shows more accurate and focused image where model parameters have changed. Also, applying the timelapse inversion method to the leakage detection of an embankment dam, we can confirm that there are three major leakage zones, but they have not changed over time.

A Study 2nd Proposal on the Sizing System for Middle-School Girls' Clothing (여중생의 기성복 치수적합성과 치수체계에 관한 연구)

  • Kim Nok-Yeon;Choi Hei-Sun
    • Journal of the Korean Society of Costume
    • /
    • v.55 no.6 s.96
    • /
    • pp.67-81
    • /
    • 2005
  • The purpose of this study is to evaluate a sizing system of ready-to-wear clothes for middle-school girls. Results of the study are as follows. 1. Results of the survey revealed most middle-school girls preferred garments for women like unisex-casual and young-casual, and prioritized overall style and design over sizing issues. However, when they purchased clothes, they were dissatisfied with the poor fit of ready-to-wear clothing, which is a little too big for average middle-school girls. 2. There is a difference between a brand's target age and its average consumer age. $96.7\%$, of respondents purchased clothes from unisex-casual and young-casual brands, which sizes did not fit for them. Most of these brands had female adults ages 18 to 24 as their targets, whose somatotypes do not correspond with those of girls 12 to 15 years old. 3. Body measurements of those in age groups from 12 to 15 and from 10 to 24 were analyzed to identify physical differences between middle-school girls and female adults, which confirmed the relevance of different sizing systems for each age group. As a result, it is undesirable that middle school girls' clothes are designed in accordance with sizing system for female adults' garments. 4. Using the two-wav distribution of middle school girls' stature-bust circumference for upper garments, and stature-waist circumference for lower garments, this study establishes a sizing system in sections of high frequency. The size intervals of stature and circumference were 5cm and 3cm respectively.

Analysis on the Changes of Urban Structure by New Town Development - Case study of Go-Yang City by GIS - (신도시 개발에 따른 도시구조 변화의 분석 - GIS를 이용한 고양시 구도심지역 변화 분석 -)

  • Lim, Dong-Il
    • The Journal of the Korea Contents Association
    • /
    • v.8 no.10
    • /
    • pp.317-327
    • /
    • 2008
  • Go-Yang city, rural region by the 1980s, had rapidly grown to the big city for only 15 years because of Il-San new town development which was developed during $1990{\sim}1995$. So the population and industrial function were greatly increased too. The change of urban spatial structure was grasped by tracing the distribution of population, household and industries of Go-Yang city during $1990{\sim}2005$. The new urban center had grown to the center of the whole city, while the industries of existing centers were extended to the neighbor areas. The existing centers had been changed into 3 types - (1) changed into a part of new urban center, (2) declined to sub-center with small merchant facilities. (3) continuously grown with the development of whole city. As a result, a new town development had changed the urban structure by creating new functional relationships among the existing and new centers rather the existing centers had declined.

A Research on the Reproductive Properties of Great Tits in the Urban Forests (도시녹지에서 박새의 번식특성에 관한 연구)

  • Jeong, Hyu-Jin;Cho, Eun-A;Ko, Hyeon-Seo;Jang, Gab-Sue
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.15 no.5
    • /
    • pp.155-163
    • /
    • 2012
  • This study was carried out to monitor reproductive responses of great tits in 17 urban forests in Daegu metropolitan city. The reproductive perspectives of great tits were surveyed by using 106 artificial bird nests, of which five or seven nests were set up in every urban forest. A ratio of artificial nests used by great tits for their reproduction was 27.4%. It was showing that forests, where the reproductive response was higher, was located at the edge of the city, or was known as having a good vegetation structure in the urban area. The laying date of a great tit was a little earlier in forests in the middle of the city. It might be dependent on the density of artificial land uses including a residential area and an industrial complex, which are able to increase an urban micro-temperature. Otherwise, natural forests or forest patches nearby natural forests located at the edge of the city were showing that the laying date of great tits was relatively later than the oneee in the forest in the middle of the city. There was a big difference of reproduction perspectives of great tit between the 1st and 2nd reproduction. In the 1st reproduction, a clutch size was larger, while an egg volume was so low. Otherwise, the clutch size was shown so smaller in the 2nd reproduction than in the 1st reproduction, while the egg volume was larger in the 2nd reproduction. It might be due to the survival strategy of a great tit to prepare the winter season for a juvenile. Many variables, regarding to the problem of climate changes, have been linked to the environment of urban area and the bird habitats. Finally, Monitoring a bird reproduction is a valuable work for managing an urban forest as well as for conserving a natural forest.

The Effect of Athlete's Achievement Goal Orientation on Life Satisfaction (운동 성취목표 성향이 선수들의 삶의 만족에 미치는 영향)

  • Hwang, Sung-Geun
    • Journal of Digital Convergence
    • /
    • v.14 no.5
    • /
    • pp.519-526
    • /
    • 2016
  • This study aims to verify the relationship between achievement goal orientation and life satisfaction. It consists of 450 athletes from high school, university, and professional teams as an object. After examining reliability and validity on questionnaires, the data, based on gender, was evaluated by analysis of variance, correlation analysis, and multiple regression analysis. The result says that male athletes have higher scores in Mastery approach and Performance approach - two of the four achievement motivation factors - which means a meaningful difference between gender. Life satisfaction also shows that male players have more satisfaction and indicates a big difference between gender. Finally, according to the multiple regression analysis on the Athlete's achievement goal orientation and life satisfaction, Mastery approach affects statically but Mastery avoidance does negatively on athlete's life satisfaction. The gender-based relationship between Athlete's achievement goal orientation and life satisfaction reveals that mastery approach gives positive effects on life satisfaction for both genders, but mastery avoidance influences negatively on male and female life satisfaction.

A Study on Characteristics of the View point Setting in Urban scape Plan -In the case of the Regional Small & Medium Cities in Jeollanamdo- (조망경관계획에서 조망점 설정 특성에 관한 연구 -전라남도 중소도시 사례를 대상으로-)

  • Park, Jung-Hyun;Kim, Yun-Hag
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.13 no.1
    • /
    • pp.9-20
    • /
    • 2011
  • This study is designed to examine characteristics and types of basic landscape design established by 7 local governments in Jeollanam-do and its availability as the index of landscape administration and present a guideline with view landscape plan of local governments. The results of this study are described below. In case of view landscape, while Korean cities have not many historical assets like landmark, they have locational characteristics with mountain or coast in the center or surroundings of downtown. Therefore, since view landscape has many cases of restricting individual property rights as well as having a value as public property of city which makes recognition of sharing city, it is very sensitive problem and establishing guideline of it is needed. But, it was found that view landscape plan of local governments established location of view spot with the nature of relief viewing downtown or coast from high spot. Selection of viewing objects in view plan require deciding an object as the public property of city and big cities require selection from the zone and small cities must select 1~2 spots from the viewpoint of whole downtown. 3~4 view spots of middle and distant views which makes city community centering around the subject of view must be selected through enough discussion and in case of natural landscape, View shaft or visible rays require setting of range that 30% of viewing objects is seen. View spot or viewing objects should be selected over twice as extra spots through public hearing and civil participation as the process.

Problems and Amelioration Measures of the Assessment on Terrestrial Ecosystem Field in Environmental Impact Statement (환경영향평가서에 나타난 육상생태분야의 평가에 대한 문제점과 개선방안)

  • Koh, Kang-Suk;Suh, Min-Hwan;Kang, In-Goo
    • Journal of Environmental Impact Assessment
    • /
    • v.4 no.1
    • /
    • pp.37-46
    • /
    • 1995
  • This study was carried out to find the problems of assessment on terrestrial ecosystem part in environmental impact analysis(EIA) and to suggest the proper amelioration measures by analyzing 19 environmental impact statements(EIS) published during the period from 1991 to 1994. The results obtained from this study were as follows. Field survey for the investigation of fauna and flora in project areas should be conducted at least 3 times a year and name of investigator should be written on the EIS clearly. Increase or decrease in degree of green naturality and productivity cannot be an absolute criteria for expressing the amount of changes in ecosystem. Evaluation for the ecosystems and their composition in project area is more important than presenting merely the increase or decrease in degree of green naturality and productivity. Alleviation measures in 19 EISs analyzed in this study were summarized into 6 types: They are establishment of landscape plan, transplanting of useful trees preservation of big tree and protected species, restoration and preservation of existent vegetation, establishment of soil conservation measures and diminution of the impact on animal. However, they were somewhat insufficient because they wouldn't suggest the alleviation measures in detail. The more positive counter-proposals are needed to decrease the impact of the project on terrestrial ecosystem.

  • PDF

A Study on the Applicability of Settlement Prediction Method Based on the Field Measurement in Gimpo Hangang Site (김포한강지구 계측자료를 이용한 침하예측기법의 적용성에 관한 연구)

  • Lee, Jungsang;Jeong, Jaewon;Choi, Seungchul;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
    • /
    • v.13 no.12
    • /
    • pp.35-42
    • /
    • 2012
  • There are many large-scale coastal region landfill and land development by loading to use territory efficiently, this regions are mostly soft clay ground. Constructing structures and road on the soft ground bring about engineering problems like ground shear fracture and a big amount of consolidation by bearing capacity. Improvement of soft soil is required to secure soil strength and settlement control. In improvement of soft soil, predict for the amount of settlement based on field surveyed reports are important element for estimating pre-loading banking height and the final point of consolidation. In this study, there is calculating theoretical settlement by analyzing field surveyed report and ground investigation to improvement of soft soil with pre-loading and vertical drain method. And present settlement prediction method reflect soil characteristics in Gimpo Hangang site by analysing prediction settlement and observational settlement during compaction using hyperbolic, ${\sqrt{s}}$, Asaoka method.