• 제목/요약/키워드: Shape understanding

검색결과 575건 처리시간 0.031초

실험적 방법을 통한 에어컨 실내기의 소음원 검출에 관한 연구 (A Study on Noise Identification of Indoor Air-conditioner Using Experimental Methods)

  • 이성진;오재응;이정윤;강태호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.87-87
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    • 2004
  • An air-conditioner has various noise sources such as a fan noise, a motor noise, and a vibration induced noise. To reduce these noise effectively, noise sources must be identified. Especially in this paper, the structure borne sound radiated from the motor bracket of the indoor air-conditioner is considered. To do this, the operational deflection shape, which is used for understanding of the behavior of the motor bracket at a particular frequency, is obtained and compared with the sound intensity, which is used for the noise identification. Through this study, the noise sources of indoor air-conditioner are defined and the effective noise reduction method is proposed.

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난류경계층의 헤어핀 다발구조에 대한 3차원 토폴로지 규명 (Identification of the three-dimensional topology of hairpin packet structures in turbulent boundary layers)

  • 권성훈;김경천
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.610-615
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    • 2003
  • This experiment has been carried out to find the structure of turbulent boundary layer with instantaneous velocity fields obtained in stream-wall-normal planes using a stereo-PIV (Particle Image Velocimetry) method. And it has been measured perpendicular plane and horizontal plane with hairpin vortex structure by Reynolds number change and made third dimension shape for section of horizontal plane through stereo-PIV. In the outer layer hairpin vortices occur in streamwise-aligned packets that propagate with small velocity dispersion. A streaky structure is composed of counter-rotating vortex. According as y+ increases, streaky structure's interval space decrease, and it shows that hairpin shape of prior research is vertified. The objective of the present research is to gain a better understanding of coherent structures in the outer of wall turbulence by experimentally examining coherent structures.

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AUTOMATIC BUILDING EXTRACTION BASED ON MULTI-SOURCE DATA FUSION

  • Lu, Yi Hui;Trinder, John
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.248-250
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    • 2003
  • An automatic approach and strategy for extracting building information from aerial images using combined image analysis and interpretation techniques is described in this paper. A dense DSM is obtained by stereo image matching. Multi-band classification, DSM, texture segmentation and Normalised Difference Vegetation Index (NDVI) are used to reveal building interest areas. Then, based on the derived approximate building areas, a shape modelling algorithm based on the level set formulation of curve and surface motion has been used to precisely delineate the building boundaries. Data fusion, based on the Dempster-Shafer technique, is used to interpret simultaneously knowledge from several data sources of the same region, to find the intersection of propositions on extracted information derived from several datasets, together with their associated probabilities. A number of test areas, which include buildings with different sizes, shape and roof colour have been investigated. The tests are encouraging and demonstrate that the system is effective for building extraction, and the determination of more accurate elevations of the terrain surface.

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기어 정밀정형 성형을 위한 후 공정으로서의 냉간 아이어닝 공정에 대한 연구 (Experimental and Numerical Study of Cold Ironing as a Post-Process of Net-Shape Manufacture of Gears)

  • 장유철;박철성;김병민;;강범수
    • 대한기계학회논문집A
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    • 제26권10호
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    • pp.2096-2103
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    • 2002
  • Cold ironing, as a post-forging operation of warm forged gears, needs a clear understanding of form errors due to die-elasticity and springback of component. In order to simplify the analysis of cold ironing, a single tooth instead of a whole gear component was investigated. The influence of initial surface roughness, die design, and die/workpiece interference has been examined experimentally and numerically. As a result the changes in geometrical profile, dimensions, and surface finish in a single tooth were observed. This study demonstrates that predicted dimensions can be achieved and surface finish also can be greatly improved.

Study on small resistance regions in post-liquefaction shear deformation based on soil's compressive properties

  • Jongkwan Kim;Jin-Tae Han;Mintaek Yoo
    • Geomechanics and Engineering
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    • 제36권3호
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    • pp.295-301
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    • 2024
  • Understanding the post-liquefaction shear behavior is crucial for predicting and assessing the damage, such as lateral flow, caused by liquefaction. Most studies have focused on the behavior until liquefaction occurs. In this study, we performed undrained multi-stage tests on clean sand, sand-silt mixtures, and silty soils to investigate post-liquefaction shear strain based on soil compressibility. The results confirmed that it is necessary to consider the soil compressibility and the shape of soil particles to understand the post-liquefaction shear strain characteristics. Based on this, an index reflecting soil compressibility and particle shape was derived, and the results showed a high correlation with post-liquefaction small resistance characteristic regardless of soil type and fine particle content.

패션에 나타난 한국미의 조형성과 디자인 요소 (Design Factor and Formative Characteristic on Korean Aesthetic in Fashion)

  • 유현정
    • 한국의상디자인학회지
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    • 제12권1호
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    • pp.51-59
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    • 2010
  • The purpose of this study is to help understanding of Korean fashion image by studying of design factor and formative characteristic. The methods of this study are the study of academic literatures as well as practical study through the analysis of case studies about actual works. The summary of this study's results is like followings. First, Perspectives seeing formative characteristic on Korean fashion image are Shape with a line, color, material, pattern, accessories. Second, Design factors deciding Korean fashion image are pattern, then in order of shape, color, material, accessories. Third, In results on design factor deciding Korean fashion image, when fashion designers focus on pattern, pattern is focused on without regard for other design factor. But color and material are accompanied by other design factor in expressing Korean fashion image. As fashion design point expressing Korean astetic, use of pattern is minimized other design factor, color and material are used with other design factor, then Korean fashion image will come out more than other time else. If We develop Korean fashion design to concentrate on shape and pattern, Korean fashion culture will be known to world people and beautiful value of Korean fashion will be handed effectively.

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휨 구조시스템의 구조디자인적 구성요소와 디자인 조합 수법 분석 (A Study on Design Methods and the Composition Elements in Flexure Structure Systems)

  • 이주나
    • 한국공간구조학회논문집
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    • 제16권1호
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    • pp.73-84
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    • 2016
  • This study analyzes the four composition elements : profile, anchorage and connection, material and member rigidity, stability, as the main composition design elements of flexure structure systems, in order to explore possibilities for more various structure designs in architectures with flexure structure system. It also examines typical design methods that use the mentioned four composition elements. At the results, this research presents an understanding of the differences between funicular shape and non-funicular shape and mechanical features of the shapes in the profile element, regarding to the ratio of rise height to span length(f/l). Also, the typical design methods are presented for the designable usages of the hinge joints and the fix joints, and for the applications of member rigidity expressed by the index of the ratio of member depth to span length(d/l). And it was presented that connection styles, addition of brace members, placement of shear walls are the main design methods in the stability element. This data would be useful to architectural designs concerning integrated design with structures.

초등학교 수학과 입체도형 영역의 학습 RIA 개발 (Development of Rich Internet Application in the Three-Dimensional Shapes of Elementary Mathematics)

  • 김갑수;유태호
    • 정보교육학회논문지
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    • 제12권4호
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    • pp.395-404
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    • 2008
  • 초등학교 수학과 입체도형 학습은 구체물을 활용한 구체적 조작을 통해서 추상적인 입체도형을 직관적으로 이해하도록 돕는 다양한 활동이 필요하다. 입체도형 학습에 있어 구체물의 활용은 효과적이지만, 구체물에서는 확인이 어려운 전개도나 다양한 형태의 입체도형 등은 컴퓨터의 반구체물을 활용하는 것이 효과적이다. 또한 컴퓨터를 활용하게 되면 방과 후에도 같은 학습 자료를 학생들이 활용할 수 있어서 구체물을 활용한 학습의 한계를 보완할 수 있다. 본 연구에서는 플렉스와 플래시를 개발도구로 사용하여 초등학생 수준에서 쉽게 조작하고 사용할 수 있도록 학습 어플리케이션을 개발하였다. 본 연구에서 개발한 입체도형 학습 어플리케이션 활용을 통해 학생들의 직관적이고 자유로운 탐색 및 구체물의 보완, 학습 흥미유발 등의 효과가 기대된다.

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기하형상의 임의교란이 음향산란에 미치는 영향 (Effect of Random Geometry Perturbation on Acoustic Scattering)

  • 주관정
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1992년도 추계학술대회논문집; 반도아카데미, 20 Nov. 1992
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    • pp.117-123
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    • 1992
  • In recent years, the finite element method has become one of the most popular numerical technique for obtaining solutions of engineering science problems. However, there exist various uncertainties in modeling the problems, such as the dimensions(geometry shape), the material properties, boundary conditions, etc. The consideration for the uncertainties inherent in the problems can be made by understanding the influences of uncertain parameters[1]. Determining the influences of uncertainties as statistical quantities using the standard finite element method requires enormous computing time, while the probabilistic finite element method is realized as an efficient scheme[2,3] yielding statistical solution with just a few direct computations. In this paper, a formulation of the probabilistic fluid-structure interaction problem accounting for the first order perturbation of geometric shape is derived, and especially probabilistical acoustic pressure scattering from the structure with surrounding fluid is focused on. In Section 2, governing equations for the fluid-structure problems are given. In Section 3, a finite element formulation, based on the functional, is presented. First order perturbation of geometric shape with randomness is incorporated into the finite element formulation in conjunction with discretization of the random fields in Section 4 and 5. Finally, the proposed formulation is applied to a acoustic pressure scattering problem from an infinitely long cylindrical shell structure with randomness of radial perturbation.

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1890년${\sim}$1960년대 여자 저고리 감정 (The Appraisal of Female Jackets from the Period of $1890s{\sim}1960s$)

  • 최은수
    • 복식
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    • 제58권5호
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    • pp.178-197
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    • 2008
  • Due to the inflow of the western culture since the 19th century, female skirts and jackets have been changed considerably in detail though their basic composition was maintained. The analysis on female jackets from the start of the modern period to 1960s has been undertaken with artefacts as well as reports and research dissertations related to them. For period appraisal, analysis was divided into several periods which are from 1890s to 1910s, and every 10 years afterwards. As a result, aspects for the appraisal in each period was found. Aspects for period appraisal in modern jackets can be a change in total length and side length, a change in shape of the sleeves (from straight to round), a change in width, and a difference in closed shape of the collars. Material and color can be another aspect which shows fashionable material or new materials (man-made textile or nylon) of each period, color combination of surface and lining material as well as other parts of the jacket, use of a stiffener made with net or sheer textiles. Research using books and archives is important for the appraisal of the garment artifact. However, most of all, one should have the attitude of examining the artifacts frequently in order to achieve deeper understanding and an eye for accurate appraisal.