• 제목/요약/키워드: Geometric Patterns

검색결과 373건 처리시간 0.021초

곡면 배열 소나의 빔 균일화를 위한 빔 패턴 분석 (Beam pattern analysis for beam homogenization of conformal array sonar)

  • 최정웅;홍우영;임준석;이근화
    • 한국음향학회지
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    • 제41권6호
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    • pp.637-646
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    • 2022
  • 임의의 곡면 배열에서 단위 빔 형성에 사용되는 부배열은 조향 방위마다 기하학적 형상이 다르다. 이 때문에 조향 방위 별 부배열의 빔 패턴은 항상 균일하지 않다. 본 논문에서는 볼록 최적화를 이용한 빔 형성 기법을 곡면 배열에 적용하고, 조향 방위별 빔 성능의 균일성이 향상되는 것을 보였다. 시뮬레이션은 절단 구면 형상의 곡면 배열에 대해 수행되었다. 고각 3 dB 빔 폭의 표준 편차가 크게 감소하였으나 반대급부로 지향 지수도 감소하는 것을 관찰했다. 이를 완화시키기 위한 하나의 방법으로 쉐이딩 함수를 이용한 최적화 기법을 제안한다.

Lateral impact behaviour of concrete-filled steel tubes with localised pitting corrosion

  • Gen Li;Chao Hou;Luming Shen;Chuan-Chuan Hou
    • Steel and Composite Structures
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    • 제47권5호
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    • pp.615-631
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    • 2023
  • Steel corrosion induces structural deterioration of concrete-filled steel tubes (CFSTs), and any potential extreme action on a corroded CFST would pose a severe threat. This paper presents a comprehensive investigation on the lateral impact behaviour of CFSTs suffering from localised pitting corrosion damage. A refined finite element analysis model is developed for the simulation of locally corroded CFSTs subjected to lateral impact loads, which takes into account the strain rate effects on concrete and steel materials as well as the random nature of corrosion pits, i.e., the distribution patterns and the geometric characteristics. Full-range nonlinear analysis on the lateral impact behaviour in terms of loading and deforming time-history relations, nonlinear material stresses, composite actions, and energy dissipations are presented for CFSTs with no corrosion, uniform corrosion and pitting corrosion, respectively. Localised pitting corrosion is found to pose a more severe deterioration on the lateral impact behaviour of CFSTs due to the plastic deformation concentration, the weakened confinement and the reduction in energy absorption capacity of the steel tube. An extended parametric study is then carried out to identify the influence of the key parameters on the lateral impact behaviour of CFSTs with localised pitting corrosion. Finally, simplified design methods considering the features of pitting corrosion are proposed to predict the dynamic flexural capacity of locally pitted CFSTs subjected to lateral impact loads, and reasonable accuracy is obtained.

Research on stress distributions around welds of three-planar tubular Y-joints under out-of-plane bending moment

  • Shiliu Bao;Wenhua Wang;Jikai Zhou;Xin Li
    • Steel and Composite Structures
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    • 제49권2호
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    • pp.181-196
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    • 2023
  • Marine structures including offshore wind turbines (OWTs) always work under cyclic loads, which arouses much attention on the fatigue design. The tripod substructure is one of the typical foundation forms for fixed OWTs. The three-planar tubular Y-joint (3Y joint) is one of the important components in fatigue design as it is most likely to have cracks. With the existence of the multiplanar interaction effect, calculating the hot spot stress (HSS) of 3Y joints is complicated. To assist with fatigue design, the distributions of stress concentration factor (SCF) and multiplanar interaction factor (MIF) along weld toe curves induced by the out-of-plane bending moment are explored in this study. An FE analysis method was first developed and verified against experimental results. This method was applied to build a numerical database including 1920 FE models covering common ranges of geometric parameters. A parametric study has been carried out to reveal the distribution patterns of SCF and MIF. After multidimensional nonlinear fittings, SCF and MIF distribution formulas have been proposed. Accuracy and reliability checking prove that the proposed formulas are suitable for calculating the HSS of 3Y joints.

A Study on 3D Virtual Clothing Fashion Design Applying Frank Stella Painting

  • Yeonji Lee;Sohee Um
    • 패션비즈니스
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    • 제27권6호
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    • pp.1-17
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    • 2023
  • This study aimed to develop a modern textile design based on the formability of Frank Stella's paintings and to develop and present a fashion design that combines modern sensibility as a 3D virtual clothing program. The formative characteristics of Frank Stella's work were 'unity due to regular stripes', 'asymmetry due to geometric surface division', and 'decorabilitydue to colorful use'. Based on this, costume patterns and textiles based on Frank Stella's paintings were developed and six 3D virtual fashion design works were produced. The conclusion was as follows. First, it was confirmed that Frank Stella's work has a very wide range of applications to fashion products as abstract expression and minimal simplicity coexist visually. Second, various colors and forms of Frank Stella's paintings could be developed using textiles with visual formability, and originality as a fashion work applied with paintings could be maximized. Third, the development of 3D fashion using virtual programs had the ease of time efficiency, cost reduction, and spatiotemporal expansion of work processing compared to the actual costume production process. In addition, the simulation of 3D virtual wear made it easy to modify and recover the position of the textile to be applied to the costume and create a new design in the process of transforming the position of various textiles. It is expected that this study results will be used as basic data for the future conversion content industry in the painting and fashion industries.

몬테카를로 방법 기반의 이동최소제곱을 이용한 밀도 데이터의 벡터장 시각화 (Visualization of Vector Fields from Density Data Using Moving Least Squares Based on Monte Carlo Method)

  • 김종현
    • 한국컴퓨터그래픽스학회논문지
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    • 제30권2호
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    • pp.1-9
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    • 2024
  • 본 논문에서는 밀도 데이터로부터 다양한 벡터장 패턴을 시각화하는 새로운 방법을 제안한다. 이를 위해 물리 기반 시뮬레이션과 기하학적 처리에서 사용되는 이동최소제곱(Moving least squares, MLS)을 이용한다. 하지만 일반적인 MLS는 벡터기반의 제약조건을 통해 고차 보간되기 때문에 밀도의 특성을 고려하지 못한다. 본 논문에서는 입력 데이터에 내포되어 있는 밀도의 특성을 효율적으로 고려하기 위해 몬테카를로 기반의 가중치를 MLS에 통합하여 다양한 형태의 백터장을 표현할 수 있도록 알고리즘을 설계한다. 결과적으로 일반적인 MLS와 발산제약 기반의 MLS 같은 기존 기법으로는 표현하기 힘든 디테일한 벡터장을 실험을 통해 보여준다.

카지미르 말레비치의 조형적 요소를 AI 프롬프트로 활용한 3D 디지털 패션디자인 연구 (A Study of 3D Digital Fashion Design Using Kazmir Malevich's Formative Elements as AI Prompt)

  • 이주영
    • 패션비즈니스
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    • 제28권3호
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    • pp.122-139
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    • 2024
  • Image-generated AI is rapidly emerging as a powerful tool to augment human creativity and transform the art and design process through deep learning capabilities. The purpose of this study was to propose and demonstrate the feasibility of a new design development method that combined traditional design methods and technology by constructing image-generated AI prompts based on artists' formative elements. The study methodology consisted of analyzing Kazmir Malevich's theoretical considerations and applying them to AI prompts for design, print pattern development, and 3D digital design. This study found that the suprematist works of Kazmir Malevich were suitable as design and print pattern prompts due to their clear geometric shapes, colors, and spatial arrangement. The AI-prompted designs and print patterns produced diverse results quickly and enabled an efficient design process compared to traditional methods, although additional refinement was required to perfect the details. The AI-generated designs were successfully produced as 3D garments, thereby demonstrating that AI technology could significantly contribute to fashion design through its integration with artistic principles. This study has academic significance in that it proposes a prompt composition method applicable to fashion design by combining AI and artistic elements. It also has industrial significance in that it contributes to design innovation and the implementation of creative ideas by presenting an AI-based design process that can be practically applied.

A Study on the Characteristics of Knitwear Fashion Design: With a focus on Missoni, Sonia Rykiel, Azzedine Alaia

  • Chun, Hei Jung;Park, Jae Min
    • International Journal of Costume and Fashion
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    • 제13권1호
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    • pp.23-34
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    • 2013
  • The purpose of this study is to better understand the development and characteristics of knitwear fashion design by examining the transformation process of the modern knits. The subjects of the study are Missoni, Sonia Rykiel, and Azzedine Alaia, designers who are world-renowned knit designers, and the expressive techniques in their designs will be evaluated. The study also intends to analyze the aesthetic value of each designer's style through their product's silhouette, colors, and knitting techniques. On the basis of the analysis, we hope to research the factors in the designing process that will allow knits, which were made for practical purposes, to be valued as a luxury fashion item, and with the results, show the potential for knits in expanding its domain in fashion to become a more luxurious, creative fashion item. The characteristic comparison of the designers is as follows: First, in the case of colors, Missoni shows its distinct identity through a balance of splashy colors as well as nature-inspired color composition and balance. And, only with color use, is also able to express perspective, form composition, and rhythm. Sonia Rykiel designs are composed of black backgrounds with strong primary colors that are contrasted with one-point or stripes to express a light, urban image. Alaia emphasizes femininity by the use of black and white colors, which show modernity, in combination with neutral skin-toned colors, such as beige and gray. So, in other words, Missoni and Sonia Rykiel mixed colors for visual interconnectivity, while Alaia expressed femininity through the use of an achromatic color. Second, in the case of knitting techniques, Missoni uses the jacquard technique to make complex patterns that show balance of colors and patterns such as zigzag, stripe, geometries, and titan check, which are geometric, abstract, and symmetric. Sonia Rykiel who uses stripes as her trademark, most often utilizes the intarsia technique, which is expressed through one-point. Alaia combines diverse techniques, such as the Skashi weaving, by using computerized knitting. Third, as for silhouettes, Missoni eliminated exaggerated details in order to emphasize the flashy colors and delicate patterns and weavings of its designs, and this resulted in simplistic and relaxed silhouettes. Sonia Rykiel took advantage of the elasticity that the knit offers to get a tight silhouette, and in turn, emphasized the female sensuality. Alaia used curvilinear cuts that emphasized the womanly curves and gained an image considered soft and feminine.

현대(現代) 패션에 나타난 고저스(Gorgeous) 이미지에 관(關)한 연구(硏究) - 중세(中世) 비잔틴 시대(時代)의 이미지를 중심(中心)으로 - (A Study of Gorgeous Images in Modern Fashion - Focus on Byzantine Empire in the Middle Ages -)

  • 정윤희
    • 패션비즈니스
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    • 제6권5호
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    • pp.48-58
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    • 2002
  • The purpose of this study is to analyze four separate elements-sublime beauty, elegant beauty, mysticism, ornament-which appeared in materials, patterns, colors, silhouettes, details, and accessories, laying stress on luxurious, brilliant, mysterious feelings on Gorgeous Images appeared as trend theme of modern fashion by mixing religious mysticism of the Byzantine Empire. Mysticism element is using the effect of splendid and gorgeous colors from the Orient rather than forms. And a philosophy of abundant colors in mosaics, which are seen in art forms such as architecture, paintings, etc., shows that it creates some visual rooms for religious spirits. Influenced by the fashion of the Greco-Roman style, the elegant beauty element is expressing abundant comfort and elegant feminine lines that are from creases, and it is also emphasizing natural beauty which seems to slip down by displaying the splendid images of Gorgeous as drapes that fit a body. Ornament element was reflecting an inspiration from the splendid and brilliant culture of religion in the Byzantine Age. Therefore, it was appeared as a style filling the whole with bulky silks, splendid ornamental materials embroidered in gold or silver thread, the complicated geometric patterns that are two-dimensional and dignified, and so on. It was decorated with crosses which represent Christianity as a motif, and also it emphasized the splendor of the Byzantine and dazzling splendid images of Gorgeous by using accessaries decorated with various jewels. The elements of sublime beauty are showing the beauty adding humble and majestic images to it as designs sought by spiritual values or intrinsic values. Those designs, so to speak, have pretense which does not allow to expose a body and plain pure feeling, so that they are showing some abstinent styles in a solemn atmosphere, with most details removed. We can say the Fashion Theme appearing in Modern Times is the result from representing by combining various factors of the times with formative beauty through creative works for aesthetic expression. The moderners are requiring new designs which is possible to meet their individualities, in addition to their outstanding fashion senses. From this point of view, a variety of textiles, patterns, and colors in the Byzantine have a great meaning to fulfill people's various desires as interesting elements.

다양한 노출 매트릭스를 통한 송전선로 주변과 비 주변 거주 초등학교 학생의 극저주파 자기장 노출량 평가에 관한 연구 (Exposure Assessment of Extremely Low Frequency Magnetic Fields by variable exposure matrices for the Selected Primary Schoolchildren Living Nearby and Away from a Overhead Transmission Power Line)

  • 김윤신;현연주;최성호;이철민;노영만;조용성;홍승철
    • 한국산업보건학회지
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    • 제16권4호
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    • pp.334-345
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    • 2006
  • The objectives of this study were to analyze and compare 24 hrs personal exposure levels of MF at microenvironments such as home, school, educational institute, internet pc game room, transportation, and other places according to time activity patterns using various metrics for children attending the primary schools located near and away from the power lines, and to characterize the major microenvironments and impact factors attributed personal exposure level. The study was carried out for 44 children attending a primary school away from the lines(school A) and 125 children attending a school away from 154 kV power lines(school B), all who aged 12 years and were 6 grade, from July 2003 to December 2003. All participants filled in a questionnaire about characteristics, residence, use of electrical appliances and others. Children wore a small satchel in which EMDEX II and Lite (Enertech, Co. Ltd) and a diary of activity list for period of registration in 20 minutes blocks. All statistical calculations were made with the SAS System, Releas 6.12. The summary of results was presented below. First, about the characteristics of subjects, there no differences between two groups. The subject almost spent about 56 % of their time at home and about 20~25 % of their time at school. Fifty percent of children spent 2 hours at private educational institutes. Second, the personal exposure measurements of children in school B was statistically higher than those of children in school A by various metrics such as arithmetic mean, geometric mean, percentile(5, 25, 50, 75, 95), maximum, rate of change metric, constant field metric. The arithmetic and geometric mean magnetic fields during the time the children were at school B were 0.98 and $0.86{\mu}T$ and were about 23 times higher than those of children were at school A. In conclusion, the significant major determinants of personal exposure level is the distance from the power line to microenvironments.

환경 친화적 도로 설계를 위한 기초 연구 (노선대 지형 및 지역 요소를 고려한 일반국도 주행속도 예측 모형) (A Study On Context Sensitive Highway Design Based On Improved Operating Speed Prediction Methods in National Roads)

  • 김상엽;최재성
    • 대한교통학회지
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    • 제23권7호
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    • pp.17-33
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    • 2005
  • 도로설계속도는 해당도로 규격을 결정하는 매우 중요한 설계요소이다. 설계속도 결정시 개통후 차량 주행속도를 예측하여 상관성이 높도록 계획해야 하는데, 기존 일반국도 주행속도 예측 모형은 설계속도에 따른 기하구조 요인만을 고려하여 도로의 주변환경을 고려하지 못하는 한계가 있다. 주변환경을 충분히 고려하지 않을 경우 과도한 공사비 지출과 지나친 환경 파괴우려가 있다. 따라서 본 연구에서는 도로 주변환경요소를 고려하는 주행속도 예측모형식의 정립을 시도했고, 연구결과는 다음과 같다. 첫째, 우리나라 일반국도의 지형 및 지역 요소를 운전자의 시각 특성과 GIS 프로그램을 활용하여 정의하였다. 둘째, 이렇게 구축한 지형 및 지역 특성이 차량의 주행속도에 미치는 영향을 살펴보았다. 그 결과, 지형 및 지역 별로 95% 신뢰도에서 속도차이가 있는 것으로 판단되었다. 섯째, 일반선형 모형(GLM)을 통하여 기하구조 요인과 지형 및 지역 요인을 모두 고려한 예측 모형식을 수립해 보았는데, R-Square가 양방향 2차로는 0.67, 양방향 4차로가 0.85로 나타났다. 끝으로 본 연구에서 개발한 모형을 바탕으로 지형 및 지역요소를 감안한 적정 도로 설계속도 범위를 제시했다. 이 방법론에 따라 산출된 관련 설계속도 범위는 일반국도에 대해 적용할 수 있지만, 지방도등 타 도로에 대해서는 직접 적용하기 곤란하다.