• 제목/요약/키워드: Mixed patterns

검색결과 682건 처리시간 0.028초

소결법에 의한 다공질유리의 제조 (Preparation of Porous Glass by the Sintering)

  • 박용완;이준영
    • 한국세라믹학회지
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    • 제31권9호
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    • pp.957-968
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    • 1994
  • Manufacturing process of porous glass by the filler method was studied. Commercial soda-lime-silicate glass powder was mixed with inorganic salt as the filler such as KCl, K2SO4, Na2SO4. Sintering shrinkages of mixed powders with the variation of sintering temperature were compared, and the effects of the fillers to shrinkages of mixed powder were increased in the order of Na2SO4${\mu}{\textrm}{m}$ of pore diameter were manufactured when the filler sizes 100~200 ${\mu}{\textrm}{m}$. The open pore volume of porous glass is determined by the quantity of filler and porous glasses having open pore volume between 30 and 70 vol% are available. Available sintering temperature range for preparation of porous glass is from the softening temperature of the glass powder to eutectic melting temperature of DTA curve of mixed powder.

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동시 회전하는 수평 실린더 내 환상공간에서의 혼합대류 (Mixed-Convection in an Annulus Between Co-Rotating Horizontal Cylinders)

  • 이관수;김양현;임광옥
    • 대한기계학회논문집B
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    • 제26권4호
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    • pp.622-628
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    • 2002
  • Numerical analysis has been carried out for two-dimensional steady and unsteady mixed convection in the annulus between co-rotating horizontal cylinders with a heated inner cylinder. The ratio of annulus gap($\sigma$) is taken from 1 to 10 and the order of mixed-convection parameter B(=Gr/(1+Re)$^2$) varies from 10$^4$to $10^0$. The flow patterns over this parameter range are steady multicellular, oscillatory multicellular or steady unicellular. The addition of co-rotating of both cylinders stabilizes the flow in the annulus and weakens the unsteadiness. Even in the large values of rotating parameter such as of $10^0$/($\sigma$=2) and 10$^2$($\sigma$=10), the flow pattern becomes asymptotic to the steady unicellular flow, like as in the rigid-body rotating flow.

사각채널 내 고 Pr 수의 혼합대류 볼텍스 유동에 관한 3차원 수치적 연구 (Three-Dimensional Numerical Study on Mixed Convective Vortex Flow in Rectangular Channels at High Prandtl Number)

  • 박일룡;배대석
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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    • pp.29-30
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    • 2005
  • A three-dimensional numerical calculation has been performed to investigate mixed convective vortex flow in rectangular channels(width/height=4) with the upper part cooled and the lower part heated uniformly. In this study, the Prandtl number was 909, the Reynolds number was varied from 0 to $9.6{\times}10^{-2}$ and the Rayleigh number from $10^3$ to $5{\times}10^4$. The governing equations were discretized using the finite volume method. From a parametric study, velocity and temperature distributions were obtained and discussed. It is found that vortex flow of mixed convection in rectangular channels can be classified into three flow patterns which depend on Reynolds and Rayleigh numbers, and the regular vortex structure disappears around Rayleigh number $5{\times}10^4$.

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Flow Visualization and Measurement of Velocity and Temperature in Parallel Plates

  • Piao, R.-L;Bae, D.-S
    • Journal of Advanced Marine Engineering and Technology
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    • 제28권2호
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    • pp.277-284
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    • 2004
  • This paper describes the influence of through-flow on the mixed convection in a parallel plates with the upper part is cooled and the lower part heated. When forced convection is imposed on natural convection, it is found that the flow pattern of mixed convection in the parallel plates can be classified into three patterns which were affected by Reynolds number. In such a mixed convection, the flow pattern plays an important role in the heat transfer process. In this study, thermo-sensitive liquid crystal suspension method is employed, then the visualization image acquired through the above method is processed by the color image processing technique and the two-dimensional velocity vector and temperature configuration are measured simultaneously.

Making Sense of Drawn Models for Operations of Fractions Involving Mixed Numbers

  • Noh, Jihwa
    • East Asian mathematical journal
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    • 제34권2호
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    • pp.203-217
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    • 2018
  • This study examined preservice elementary teachers' patterns and tendencies in thinking of drawn models of multiplication with fractions. In particular, it investigated preservice elementary teachers' work in a context where they were asked to select among drawn models for symbolic expressions illustrating multiplication with non-whole number fractions including a mixed number. Preservice teachers' interpretations of fraction multiplication used in interpreting different types of drawn models were analysed-both quantitatively and qualitatively. Findings and implications are discussed and further research is suggested.

우리나라 유아 및 학령기 아동의 외식패턴에 따른 식사의 질 평가: 2016-2018 국민건강영양조사 자료 활용 (Evaluation of diet quality according to the eating-out patterns of preschoolers and school-aged children in South Korea: based on data from the 2016-2018 Korea National Health and Nutrition Examination Survey)

  • 주유나;이영미;송경희;이유진
    • Journal of Nutrition and Health
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    • 제54권2호
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    • pp.165-178
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    • 2021
  • 본 연구는 2016-2018년도 국민건강영양조사 자료를 활용하여 우리나라 만 3-11세 유아 및 학령기 아동 중 저녁식사로 외식을 한 306명을 대상으로 24가지 식품군별 에너지 섭취 기여율을 계산하여 외식패턴을 도출하고, 패턴별로 인구사회학적 특성과 에너지 및 영양소 섭취 수준을 비교함으로써 유아 및 학령기 아동의 외식패턴과 식사의 질 관계를 규명하고자 하였다. 군집분석을 실시한 결과, 밥류 및 기타 잡곡류의 에너지 섭취 기여율만 높은 밥중심 (53%) 패턴과 면류, 떡류, 피자·햄버거·튀김류, 육류 및 그 제품 등의 에너지 섭취 기여율이 높은 혼합식 패턴 (47%)이 도출되었다. 주요 영양소 열량 구성비는 혼합식 패턴 (48:20:31)이 밥중심 패턴 (62:15:21)보다 탄수화물 에너지 섭취 비율이 낮고, 지방 에너지 섭취 비율이 높았다. 단백질, 나트륨의 평균 섭취는 두 패턴 모두 섭취기준을 2배 이상 초과하였고, 비타민 A와 칼슘은 두 패턴 모두 섭취기준 대비 2/3 미만 수준에 불과하였다. 혼합식 패턴은 에너지, 리보플라빈, 나이아신, 인, 철의 섭취량이 모두 섭취기준을 초과한 반면, 밥중심 패턴은 수분, 식이섬유, 비타민 C, 칼륨의 섭취량이 모두 섭취기준 대비 절반 수준이거나 그 미만으로 매우 낮았다. 비타민 A, 리보플라빈, 나이아신, 비타민 C, 칼슘, 인의 영양소 적정 섭취비와 평균 영양소 적정 섭취비는 혼합식 패턴이 밥중심 패턴보다 높았다. 영양 질적 지수는 리보플라빈, 나이아신, 비타민 C, 칼슘에서 혼합식 패턴이 밥중심 패턴보다 높았으나, 비타민 A, 비타민 C, 칼슘은 두 패턴 모두 1.0 미만으로 영양소 밀도가 부족했다. 식품군섭취패턴은 두 패턴 모두 1순위가 GMV (곡류군 + 육류군 + 채소군) 유형이었으나 밥중심 패턴이 55.8%로 혼합식 패턴 33.6% 보다 더 많았다. 종합하면, 우리나라 유아 및 학령기 아동의 외식을 통한 식사의 질은 패턴에 따라 양상은 달랐으나, 두 패턴 모두 양적 그리고 질적으로 적정하지 않았다. 따라서 외식에서 이러한 문제점을 보완한 어린이용 메뉴의 개발 및 정책적으로 외식에서의 어린이용 메뉴에 대한 기준을 세우는 것이 시급하다. 또한, 유아 및 학령기 아동과 부모를 대상으로 건강한 식품 선택에 관한 교육이 병행될 필요가 있다.

단일방출제에 섞인 혼합 성페로몬 미끼를 이용한 복숭아순나방, 복숭아심식나방, 복숭아명나방의 성충 포획 (Adult Trapping using Sex Attractants of Grapholita molesta, Carposina sasakii and Conogethes punctiferalis mixed in Single Dispensers)

  • 정진교;최경희;한경식;이순원;부경생;조영식
    • 한국응용곤충학회지
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    • 제60권1호
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    • pp.71-78
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    • 2021
  • 각기 다른 화합물들을 성유인제로 이용하는 3종 과수해충인 복숭아순나방(Grapholita molesta), 복숭아심식나방(Carposina sasakii), 복숭아명나방(Conogethes punctiferalis)을 대상으로 단일 성페로몬 미끼 방출제에 2종 혹은 3종의 성페로몬 미끼를 섞어 복숭아원과 사과원에서 유인력을 검정하였다. 복숭아원에서 실시된 복숭아순나방 유인에서 복숭아심식나방이 섞인 혼합미끼 트랩에서 유인력이 감소하였으나, 혼합미끼를 이용한 복숭아원에서의 성충밀도 변이는 단일미끼 트랩과 높은 상관성 보였다. 사과원에서는 복숭아순나방에 대한 혼합미끼의 유인력 감소는 관찰되지 않았다. 복숭아심식나방 유인은 복숭아원과 사과원 모두에서 혼합미끼의 유인력은 단독미끼의 유인력과 유의한 차이가 없었고, 복숭아원에서 단독미끼와 혼합미끼 사이의 성충 밀도 변이 양상도 상관성이 높았다. 복숭아명나방 유인에서는 포획수가 너무 적어 평가가 불가능하였다. 이상의 결과에서 복숭아순나방과 복숭아심식나방 혼합미끼는 예찰에 이용할 수 있을 것으로 추정되었다.

최적화에 근거한 LAD의 패턴생성 기법 (Optimization-Based Pattern Generation for LAD)

  • 장인용;류홍서
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2005년도 추계학술대회 및 정기총회
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    • pp.409-413
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    • 2005
  • The logical analysis of data(LAD) is an effective Boolean-logic based data mining tool. A critical step in analyzing data by LAD is the pattern generation stage where useful knowledge and hidden structural information in data is discovered in the form of patterns. A conventional method for pattern generation in LAD is based on term enumeration that renders the generation of higher degree patterns practically impossible. In this paper, we present a new optimization-based pattern generation methodology and propose two mathematical programming medels, a mixed 0-1 integer and linear programming(MILP) formulation and a well-studied set covering problem(SCP) formulation for the generation of optimal and heuristic patterns, respectively. With benchmark datasets, we demonstrate the effectiveness of our models by automatically generating with much ease patterns of high complexity that cannot be generated with the conventional approach.

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선의 형태에 의한 기하학무늬 패션디자인 개발 - 디지털 텍스타일 프린팅 기법을 중심으로- (A Study on Fashion Design with Geometric Pattern by Linear Type - Focusing on Digital Textile Printing -)

  • 오윤정
    • 패션비즈니스
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    • 제13권4호
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    • pp.178-190
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    • 2009
  • The purpose of this study is to make reference for geometric fashion by investigating geometric patterns by linear types and to propose high value added print and fashion design by designing and producing geometric prints and apparel with them focusing on digital textile printing. As a method of the study, visual and textural data were investigated for theory of geometric pattern and fashion design samples were illustrated. The geometric pattern could be defined as abstract pattern which was crossed with straight line or curve. We could group it into three classes such as straight linear, curved, and mixed type. Images varied with linear types. The image of straight linear type was sharp and modern, that of curved one was soft and feminine and that of mixed one was gorgeous and artistic. And then, 3 geometric prints and 3 one-pieces were designed. The concept of design was simple optimism which was based on sixties. Target was young optimistic women group from the mid teens to the mid twenties who continued to seek after their unique individuality keeping their modern lifestyle. Geometric patterns with straight linear, curved, and mixed type were designed and dresses which went well with them were designed and produced. According to the result of this study, images of geometric fashion can be represented diversely by varying linear type, digital textile printing is good method for high value added geometric fashion because of its high quality and degree of sensitivity, and geometric pattern is a good source for contemporary fashion.

고려와 주변국 직물에 표현된 식물무늬 비교 연구 (A Comparative Study of Plant Patterns Found in the Textiles of Goryeo and its Neighbor Countries)

  • 염하령;조효숙
    • 복식
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    • 제59권9호
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    • pp.71-86
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    • 2009
  • This study examines plant patterns expressed on the fabrics during the Goryeo Dynasty and many countries in the Chinese continent and analyzes their symbolism and formativeness. This study deals with clothes which is one of the most fundamental aspects in a culture and plant patterns on them; it examines the overall formativeness of plant patterns in East Asia from the 10th century to the 14th century by studying plant patterns in the Goryeo Dynasty and the contemporaneous dynasties in the Chinese continent - Five Dynasties, Song Dynasty, Western Xia Dynasty, Liao Dynasty, Jin Dynasty and Yuan Dynasty. The plant patterns of each country were categorized by the type of plant. The composition and expression of plant patterns were examined and statistically analyzed. Small flowers were found in Goryeo fabrics twice more than other types that could be clearly identified, and peony was the most popular flower used in Chinese fabrics. In terms of composition of plant patterns, both Goryeo and Chinese fabrics had plant only patterns more frequently than the patterns mixed with animals or jewels. Regarding expression methods of plant patterns, the most common one in Goryeo fabrics was the petal-type, while the branch-type is the most common one in Chinese fabrics. The plant patterns of the Goryeo Dynasty show beauty of simplicity with minimalism and simplification while expressed with brilliant sold threads on dark background, such as purple or light green, so the overall feeling of fabrics was simple yet nobel.