• Title/Summary/Keyword: Size grading

검색결과 210건 처리시간 0.027초

Fractal equations to represent optimized grain size distributions used for concrete mix design

  • Sebsadji, Soumia K.;Chouicha, Kaddour
    • Computers and Concrete
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    • 제26권6호
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    • pp.505-513
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    • 2020
  • Grading of aggregate influences significantly almost all of the concrete performances. The purpose of this paper is to propose practicable equations that express the optimized total aggregate gradation, by weight or by number of particles in a concrete mix. The principle is based on the fractal feature of the grading of combined aggregate in a solid skeleton of concrete. Therefore, equations are derived based on the so-called fractal dimension of the grain size distribution of aggregates. Obtained model was then applied in such a way a correlation between some properties of the dry concrete mix and the fractal dimension of the aggregate gradation has been built. This demonstrates that the parameter fractal dimension is an efficacious tool to establish a unified model to study the solid phase of concrete in order to design aggregate gradation to meet certain requirements or even to predict some characteristics of the dry concrete mixture.

컬러 컴퓨터시각에 의거한 건표고 등급 선별시스템 개발 (Development of Grading and Sorting System of Dried Oak Mushrooms via Color Computer Vision System)

  • 김시찬;최동엽;최선;황헌
    • Journal of Biosystems Engineering
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    • 제32권2호
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    • pp.130-135
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    • 2007
  • An on-line real time grading and sorting system for dried oak mushrooms was developed for on-site application. Quality grades of the mushrooms were determined according to an industrial specification. Three dimensional visual quality features were used for the grading. A progressive color computer vision system with white LED illumination was implemented to develop an algorithm to extract external quality patterns of the dried oak mushrooms. Cap (top) and gil (stem) surface images were acquired sequentially and side image was obtained using mirror. Algorithms for extracting size, roundness, pattern and color of the cap, thickness, color of the gil and amount of rolled edge of the dried mushroom were developed. Utilizing those quality factors normal and abnormal ones were classified and normal mushrooms were further classified into 30 different grades. The sorting device was developed using microprocessor controlled electro-pneumatic system with stainless buckets. Grading accuracy was around 97% and processing time was 0.4 s in average.

국산 침엽수재의 육안 등급구분방법 및 허용응력설정에 관한 총설 (Review of Visual Grading and Allowable Stress Determination Methodologies for Domestic Softwood)

  • 공진혁;정기영
    • Journal of the Korean Wood Science and Technology
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    • 제43권1호
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    • pp.25-35
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    • 2015
  • 본 연구에서는 국산 침엽수재의 육안 등급구분과 허용응력설정에 관한 국내의 학술논문을 정리하였다. 국립산림과학원 고시(KFRI 1995-27, KFRI 2000-39, KFRI 2007-3, KFRI 2009-1)를 활용하여 국산 낙엽송재의 육안 등급 구분한 연구를 비교한 결과 등급구분 비율이 연구자마다 상이했다. 보다 신뢰할 수 있는 등급구분 분류를 위해서 공증된 목재이용 기관에서 숙련된 연구자에 의한 등급구분을 시행하여야 할 것으로 사료된다. 허용응력설정에 관한 연구를 고찰한 결과, 연구자 마다 허용응력산출 방법이 ASTM D 245, KS F 2152, JAS 1990으로 모두 상이했다. 이는 침엽수 구조용재(KS F 3020)에서 기준허용응력을 제시하고 있지만 허용응력을 산출하는 명확한 방법이 제시되어 있지 않기 때문인 것으로 나타났다. 따라서 공식적인 허용응력 결정방법이 제정되어야 할 것으로 사료된다.

수확기 통마늘의 물리적 및 형상적 특성에 기초한 마늘 품질 분석 - 마늘 등급판정을 위한 판별 알고리즘 - (The Analysis of Garlic Quality Based on Physical and Morphological Properties of a Whole Bulb of Garlic at the Harvesting Season - Discrimination Algorithms for Garlic Quality Grading -)

  • 박준걸;장영창;노광모;이충호
    • Journal of Biosystems Engineering
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    • 제24권3호
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    • pp.225-234
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    • 1999
  • This study was performed as a basic research for establishing an objective quality evaluation method on whole bulbs of garlic. The size of a whole bulb of garlic, the number and the uniformity of complete individual garlics, and the existence of bad individual garlics in the whole bulb of garlic were selected as quality grading factors. Quality discrimination algorithms with machine vision techniques were developed and verified for the four factors based on morphological and physical features of whole bulbs of garlic. Based on the results, the size discrimination by the projected area of a whole bulbs of garlic suggested four grading levels and the algorithm for predicting the number of complete individual garlics based on the peaks on its projected boundary showed ${\pm}$0.78 prediction error. In addition, the uniformity represented by coefficient of variation could be divided into four levels, but the algorithm for discriminating the existence of bad individual garlics in a whole bulb of garlic was not effective.

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치수규격 및 그레이딩을 위한 체형 유형화에 관한 연구(I) (A Study on Classifying Body Forms for the Standards Regarding Size and Grading Method(I))

  • 권숙희
    • 한국생활과학회지
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    • 제7권2호
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    • pp.63-73
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    • 1998
  • To get well-fitted ready-made clothings with beautiful silhouettes, it's better to classify body forms into several forms and to assign sizing within each form than to grade just based on body size regardless of body styles. This study illucidated the importance of drop value in the results of surveying the current values of sizing and grading. Therefore, it's meaningful to get the classification of body form with appropriate distribution of drop values of the body, and the distribution of drop value and the frequency of each form is very helpful to name the combined sizing or coverage of ready-made clothes. This study aimed at classifying body forms with various drop values using multivariate analysis for sizing and grading. Factor analysis and cluster analysis were done using measured values from 346 unmarried women. The results are as follows: 1. The factor which explains body forms was obtained by factor analysis, and the representative major 18 items which have important roles in classifying body forms were selected among the measured values with high factor loading and communality. 2. The body forms were classified into 8 groups based on the charateristics, frequencies and distributions of them obtained from cluster analysis. 3. Each classified body form showed conspicuous difference in drop value and the difference of body form mainly resulted from the difference between waist and hip rather than the difference between bust circumference and waist in Korean unmarried women.

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치수규격 및 그레이딩을 위한 체형 유형화에 관한 연구(II) (A Study on Classifying Body Forms for the Standards Regarding Size and Grading Method(II))

  • 권숙희;전은경
    • 대한가정학회지
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    • 제38권10호
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    • pp.45-51
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    • 2000
  • This study illucidated the importance of drop Value in the resets of surveying the current values of sizing and grading. Therefore, it is meaningful to get the classification of body form with the appropriate distribution of drop values of the body. The distribution of drop value and the frequency of each form is very helpful to name the combined sizing or coverage of ready-made clothes. This study aimed at classifying body forms with various drop values using multivariate analysis for sizing and grading. Factor analysis and cluster analysis were done using measured values from unmarried women. The resets are as follows; The factor which explains body forms was obtained by factor analysis, and the representative major 18 items which have important roles in classifying body forms were selected among the measured values with high factor loading and communality. 1) The body forms were classified into 3 groups based on the characteristics, frequencies and distributions of them obtained from cluster analysis. 2) Each classified body form showed conspicuous difference in drop value and the difference of body form mainly resulted from the difference between bust and hip(drop value) in Korean unmarried women. 3) Discriminant analysis showed that the most significant discriminant factor of the trunk classification were bust circumference, upper bust circumference, hip circumference and stature. 4) The cover ratio of size studied in this study for the Korean Sizing system for women's garment were founded high.

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성인여성용 브래지어 원형 개발연구(제2보) -패턴그레이딩을 중심으로- (A Study on the Development of Basic Brassiere Pattern for Adult Women(Part II)-Focusing on Pattern Grading-)

  • 박은미;손희순
    • 한국의류학회지
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    • 제26권6호
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    • pp.821-832
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    • 2002
  • The purpose of this study was to develop grading method of the basic brassiere patterns therewith, provide for 12 size's brassiere patterns and prove fitness of their's and shape. The collected data were statistically processed using the SAS 6.12 for Means, Standard Deviation, etc. The results of this study can be summarized as follows; 1. The basic sizes adopted at the first design stage (see fig.1-2) were 75AA, 75A and 75B each of which was designed as upper foundation basic pattern in reference to the cup size. At the second stage, each of the upper body foundation basic pattern was used to design lower cup, upper up, front panel and wing in their order(see fig.3-6). At the third stage, the other sizes were graded in reference to the three brassiere patterns (75AA, 75A and 75B) to produce 12 brassiere sizes(see Tab. 7-8). In order to develop the basic patterns of adult women's brassieres, 33 women were selected per 11 size combination(3 women per size combination), and then, their brassiere fitting was teated. As a result, the fronts of the basic patterns were found to have such problems as undone front center, poor levelling of upper cup's bottom line or lower cup's top line, poor shape of upper cup's outside top line and shoulder strip position. On the other hand, on the rear side of the basic patterns, the central part of the wing was slightly lifted, while the wing width and straps'interval did not befit the ful1-cup brassiere. The result of this first brassiere fitting test showed that the functionality and aesthetics of the basic pattern brassieres were more or less satisfactory, and thus, the problems were addressed for the second teat. In the second test, the aesthetics, breast-shaping effect and functionality of the basic pattern brassieres were much improved. 2. We were to present the final brassiere sizing system to extend the interior length of breast and the exterior length of breast on the basis of fitting test. Thereby, 75B$.$80A$.$80B$.$85A$.$85B's the interior lengths of breast were enlarged to 0.7cm, the rest size was enlarged to 0.5cm and the exterior length of breast was enlarged to 0.5cm regardless of sizes. 3. The upper foundation basic patterns of 75AA and 75B were presented and and the basic brassiere pattern and grading pattern were presented through to.

동일연령군에서 크기 선별에 따른 넙치(Paralichthys olivaceus) 성장, 사료효율 및 생존율의 비교 (Effect of Size Grading on Growth, Feed Efficiency and Survival in Olive Flounder (Paralichthys olivaceus))

  • 김종현;김현철;이정호;노재구;이미숙;김경길
    • 한국양식학회지
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    • 제18권3호
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    • pp.154-159
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    • 2005
  • 동일연령군의 넙치 치어를 개체 크기별 4개의 group (small group, 체중 $1.3{\pm}0.23g;$ medium group, 체중 $3.1{\pm}0.45g;$ large group, 체중 $4.9{\pm}0.57g;$ ungraded group, 체중 $3.3{\pm}1.66g$)으로 나누어 8주동안 사육하면서 크기 선별이 어류의 성장, 사료효율 및 생존율에 미치는 영향을 조사하였다. 실험종료시 체중의 분포에 따른 소형 개체(체중 10 g)의 빈도는 크기 선별한 small group에 비해 ungraded group에서 매우 높게 나타났다. 실험 전기간동안의 일일성장률은 small group 및 large group에서 각각 최고치 및 최저치를 보였으며, medium group과 선별 group (small group; medium group; large group)의 pooled data는 ungraded group에 비해 높은 수치의 일일성장률을 나타내었다. (P<0.05). 사료섭취율은 ungraded group이 medium group 및 선별 group의 pooled data에 비해 높았던 반면, 사료효율에 있어서는 ungraded group이 이들에 비해 낮게 나타났다(P<0.05). 그리고 ungraded group의 생존율은 93.3%로 99.3% 이상으로 나타난 다른 실험구들에 비해 유의적으로 낮게 나타났다(P<0.05). 결론적으로 크기가 작은 넙치는 큰 넙치가 없는 곳에서 유의하게 빠른 성장과 높은 생존율을 나타내었다. 따라서 크기 선별은 넙치 치어(체중 1-5 g)의 성장과 생존율을 향상시키기 위해서 중요한 작업이 될 수 있다.

20~30대 작은 키 여성의 인체 치수 특성 및 체형 유형 연구 (A Study on the Body Dimensions and Body Types of Short-statured Women in their 20s and 30s)

  • 남영란;이은영
    • 패션비즈니스
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    • 제24권1호
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    • pp.29-42
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    • 2020
  • The purpose of this study is to analyze the body size and body characteristics of short-statured females in their 20s and 30s using direct measurement data from the 7th size Korea, and to analyze the differences in body dimensions and proportions between the regular and tall groups of short groups. The goal is to identify the dimension areas that need attention when designing and grading patterns for this short groups. As a result, it was found that the short group was shorter in height than the regular group, and the circumferential dimension was similar to the regular group. When designing patterns the tops, the grading of the Bust point-bust point is not necessary for the height, and it is not necessary to grade the Neck point to breast point in the short and regular group. These groups showed a difference in the front silhouette but not in the side silhouette. Based on these findings, the body types were classified into the following three types: 'most bulky and heavy', 'long lower body and small shoulder', and 'small and thin'. The type 1 population was the least distributed, and the relatively small and slim type was the most common. It is expected that the results of this study can be used as a reference when setting pattern designs, grading values, and production ratios by size for short women.