• Title/Summary/Keyword: Irregularly shaped structures

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A Study on Cutting Pattern Generation of Membrane Structures Using Spline Curves (스플라인 곡선을 이용한 막구조물의 재단도 작성에 관한 연구)

  • Shon, Su-Deok;Lee, Seung-Jae
    • Journal of Korean Association for Spatial Structures
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    • v.12 no.1
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    • pp.109-119
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    • 2012
  • For membrane structure, there are three main steps in design and construction, which are form finding, statistical load analysis, and cutting patterning. Unlike the first two stages, the step of cutting pattern involves the translation of a double-curved surface in 3D space into a 2D plane with minimal error. For economic reasons, the seam lines of generated cutting patterns rely greatly on the geodesic line. Generally, as searching regions of the seam line are plane elements in the step of shape analysis, the seam line is not a smooth curve, but an irregularly divided straight line. So, it is how we make an irregularly divided straight line a smooth curve that defines the quality of the pattern. Accordingly, in this paper, we analyzed interpolation schemes using spline, and apply these methods to cutting pattern generation on the curved surface. To generate the pattern, three types of spline functions were used, i.e., cubic spline function, B-spline, and least-square spline approximation, and simple model and the catenary-shaped membrane was adopted to examine the result of generation. The result of comparing the approximation curves by the number of elements and the number of extracted nodes of simple model revealed that the seam line for less number of extracted nodes with large number of elements were more efficient, and the least-square spline approximation provided smoother seam line than other methods.

Cluster-Based Spin Images for Characterizing Diffuse Objects in 3D Range Data

  • Lee, Heezin;Oh, Sangyoon
    • Journal of Sensor Science and Technology
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    • v.23 no.6
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    • pp.377-382
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    • 2014
  • Detecting and segmenting diffuse targets in laser ranging data is a critical problem for tactical reconnaissance. In this study, we propose a new method that facilitates the characterization of diffuse irregularly shaped objects using "spin images," i.e., local 2D histograms of laser returns oriented in 3D space, and a clustering process. The proposed "cluster-based spin imaging" method resolves the problem of using standard spin images for diffuse targets and it eliminates much of the computational complexity that characterizes the production of conventional spin images. The direct processing of pre-segmented laser points, including internal points that penetrate through a diffuse object's topmost surfaces, avoids some of the requirements of the approach used at present for spin image generation, while it also greatly reduces the high computational time overheads incurred by searches to find correlated images. We employed 3D airborne range data over forested terrain to demonstrate the effectiveness of this method in discriminating the different geometric structures of individual tree clusters. Our experiments showed that cluster-based spin images have the potential to separate classes in terms of different ages and portions of tree crowns.

First Record of Amphisiella milnei (Ciliophora, Stichotrichida) from Korea

  • Choi, Jung Min;Jung, Jae-Ho;Kim, Young-Ok
    • Animal Systematics, Evolution and Diversity
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    • v.34 no.3
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    • pp.143-151
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    • 2018
  • A marine ciliate Amphisiella milnei (Kahl, 1932) $Horv{\acute{a}}th$, 1950 was discovered from the tidal pool of Baekdo Island, South Korea. The existence of extra cirri between leftmost frontal cirrus and buccal cirrus discriminates this species from its congeners. Its morphological features are described as follows: body size in vivo $110-130{\times}35-45{\mu}m$; elongate rectangular to elliptical in shape; two large and several small ring-shaped structures; yellowish cortical granules arranged irregularly on ventral side but longitudinally along dorsal kineties on dorsal side; 34-40 adoral membranelles, 3 frontal cirri, 1 buccal cirrus, 1 parabuccal cirrus, usually 2 extra cirri behind leftmost frontal cirrus, and 3 frontoventral cirri; amphisiellid median cirral row composed of 25-31 cirri with 27-36 left and 27-44 right marginal cirri; usually 5 transverse cirri and 2 pretransverse cirri with 7 dorsal kineties; two macronuclear nodules. In addition to, 18S rDNA sequence of A. milnei was analyzed to understand its phylogenetic relationship.

Molecular Behavior and Electro-Chemical Properties of Dendrimer and Staff-type Polymer Monolayers in Crown Function Group (크라운 기능기를 포함한 덴드리머 및 Staff-type 고분자 단분자막의 분자거동 및 전기ㆍ화학적 특성)

  • 장정수
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.5
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    • pp.213-213
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    • 2003
  • We investigated the monolayer behavior at the air-water interface with metal solution, the surface morphologies and the electrical properties such as conductivity, The calculated conductivity values of pure water subphase and its complexes with L $i^{+}$ ions are 5.6$\times$10$^{-l6}$ and 1.9$\times$10$^{-14}$ [S/cm], respectively. And the calculated barrier height D values of pure water subphase and its complexes with Li. ions are 0.70 and 0.66 [eV], respectively. We also attempted to fabricate a crown dendrimer Langmuir-Blodgett (LB) films containing functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In conclusion, it is demonstrated that the metal ion around dendrimer and polymer included crown function group can contribute to make formation of network structure among crown function group and result in change of electrical properties.s.s.

Molecular Behavior and Electro-Chemical Properties of Dendrimer and Staff-type Polymer Monolayers in Crown Function Group (크라운 기능기를 포함한 덴드리머 및 Staff-type 고분자 단분자막의 분자거동 및 전기ㆍ화학적 특성)

  • 장정수
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.52 no.5
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    • pp.213-218
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    • 2003
  • We investigated the monolayer behavior at the air-water interface with metal solution, the surface morphologies and the electrical properties such as conductivity, The calculated conductivity values of pure water subphase and its complexes with L $i^{+}$ ions are 5.6$\times$10$^{-l6}$ and 1.9$\times$10$^{-14}$ [S/cm], respectively. And the calculated barrier height D values of pure water subphase and its complexes with Li. ions are 0.70 and 0.66 [eV], respectively. We also attempted to fabricate a crown dendrimer Langmuir-Blodgett (LB) films containing functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In conclusion, it is demonstrated that the metal ion around dendrimer and polymer included crown function group can contribute to make formation of network structure among crown function group and result in change of electrical properties.s.s.

The Effects of Cryopreservation on Fine Structures of Pearl Oyster(Pinctada fucata martensii) Larvae (냉동보존이 진주조개(Pinctada fucata martensii) 유생의 미세구조에 미치는 영향)

  • Choi, Youn-Hee;Jo, Pil-Gue;Kim, Tae-Ik;Bai, Sung-Chul C.;Chang, Young-Jin
    • Development and Reproduction
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    • v.11 no.2
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    • pp.79-84
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    • 2007
  • The freezing susceptibilities of two larval stages (D-shaped and umbo) of the pearl oyster (Pinctada fucata martensii) were evaluated by the electron microscopy (light, transmission electron and scanning electron). The morphological shapes were examined from each pre-frozen or frozen-thawed stage of the cryopreserved larvae in liquid nitrogen by using the cryoprotectant, dimethyl sulfoxide ($Me_2SO$) mixed with sucrose. Although a portion of the shell was damaged, the hinge and prodissoconch were intact and clearly visible after preservation in liquid nitrogen. In addition, the cytoplasm of the frozen-thawed larvae maintained the normal organelle integrities, e.g., endoplasmic reticula, lipid droplets, mitochondria, nucleus and microvilli. However, some of the frozen-thawed larvae showed irregularly arranged cilia, rough shell surfaces and round-lumped cilium heads. These results indicate that P. fucata martensii larvae are susceptible to freezing, at least at those two critical developmental stages (D-shaped and umbo), and suggest a new industrial investigation including reduction method of cell injury for preserving microbial starter cultures need to be developed.

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Effect of Pressure Gradients on the Hairpin Structures in Turbulent Boundary Layers (난류 경계층의 Hairpin와 구조에 대한 압력구배의 영향)

  • Kim, Gyeong-Cheon;Yun, Hong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.8
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    • pp.1103-1112
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    • 2001
  • The effect of pressure gradients on the hairpin structures in three different turbulent boundary layers (ZPG : Re(sub)$\theta$=910, FPG : Re(sub)$\theta$=575, APG : Re(sub)$\theta$=1290) has been examined with instantaneous velocity fields obtained in streamwise-wall-normal planes using PIV (particle image velocimetry) method. In the outer layer hairpin vortices occur in streamwise-aligned packets that propagate with small velocity dispersion. The signature pattern of the hairpin consists of a spanwise vortex core located above a region of strong second quadrant fluctuation (u<0 and v>0 : Q2 event) is clearly observed. The formation of packets explains the occurrence of multiple VITA events in turbulent burst. Noticeable differences are found in the average inclination angles of hairpin vortex packets which are 45$^{\circ}$, 35.7$^{\circ}$, and 51.9$^{\circ}$in the case of ZPG, FPG and APG, respectively. It is found that the large, time-varying, irregularly shaped zones with nearly constant streamwise momentum exist throughout the boundary layer. Within the interior of the envelope the spatial coherence between the velocity fields induced by the individual vortices leads to strongly retarded streamwise momentum, explaining the zones of uniform momentum. The formation of the uniform momentum zone is remarkably different with respect to the pressure gradients especially in the logarithmic layer.

Fine Structure and Immunogoldlabeling of Crystalline Inclusion Bodies in Mitochondria (미토콘드리아내 결정함유물의 미세구조 및 면액황금표식법)

  • ;;R.A. Capaldi
    • The Korean Journal of Zoology
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    • v.31 no.1
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    • pp.62-70
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    • 1988
  • The distribution of respiratory chain complexes in beef heart and human muscle mitochondria has been explored by immunoeledron microscopy with antibodies made against beef heart mltochondriai proteins in conjundion with protein A cofloidai gold (l2nm particles). The antibodies used were made against NADH-conezyme Q reductase(complex I), ubiquinol-cytochrome-c-oxldoreductase (complex III) and cytochrome-c-oxidase(complex IV). Labeling of bed heart tissue with any of these antihodies gave gold particles randomly distributed along the mitochondrial inner membrane. The labeling of muscle tIssue mitochondria from a patient with a mitochondrial myopathy localized by biochemical analysis to complex III was quantitated and compared with the labeling of human control muscle tissue mitochondria. Four kinds of morphological changes in the mitochondrial fine strudure in the myopathy patient tissue have been found; paracrystalline inclusions consistIng of densely packed multi- lamellar structures, globular crystalline inclusions with high electron density, multilamellar strudure inclusion body(compadly and irregularly arranged concentric whirl shaped cristae)and golbular cyrstalilne inclusions located in the center of the whirl shaped cristae. Compex I and cytochrome-c-oxldase antihodies reacted to the same level in the mitochondria containing the crystalline inclusions and control mitochondria. Antibodies to complex III reacted very poorly to the mitochondria containing the crystalline Inclusions but strongly to control mitchondria. The globular crystalline inclusions in the mitochondria are not reacted antibodies to respiratory chain complexes.

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Growth of $BaTiO_3$ Single Crystals by TSSG Technique (TSSG법에 의한 $BaTiO_3$ 단결정 육성)

  • 박봉모;정수진
    • Korean Journal of Crystallography
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    • v.3 no.2
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    • pp.120-128
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    • 1992
  • Single crysals of BaTiO3 were grown by TSSG technique at various cooling rates. Morpolo girts, defects and domain structures of the grown crystals were investigated. At the cooling rates below 0.5℃/hr, equant single crystals were obtained and the 11111 faces were dominantly developed. If the cooling rate was much faster or if the vortical temperature gradient in the so lotion was very large, the solution became unstable and the needle formed BasTil04 o crystals were precipitated. Two sets of parallel lamella domains are arranged perpendicular to each other and the irregularly shaped boundaries are fixed between them. These sets of domains show remarkable orientation contrast in x-ray topography. Heating the crystal above 127℃, the phase transition from tetragonal to cubic occurs. The phase transition front (PTF) moves in the direction of temperature gradient. Domains in the tetragonal phase are successively rearranged and regular strain patterns appear in the cubic phase. The habit plane of PTF in BaTi03 is found to deviate from a l1101 lattice plane by app roximately 9°.

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Reliability Analysis and Utilization of BIM-based Highway Construction Output Volume (BIM기반 고속도로 공사 물량산출 신뢰성 검토 및 활용)

  • Jung, Guk-Young;Woo, Jeong-Won;Kang, Kyeong-Don;Shin, Jae-Choul
    • Journal of KIBIM
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    • v.3 no.3
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    • pp.9-18
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    • 2013
  • In case of applying the BIM method in the civil engineering of irregularly shaped structure, BIM method began to be introduced in the current building engineering area compared with the expected effects of the relatively high construction productivity has been recognized. In this paper, I have developed quantity calculation algorithms applying it to earthwork and bridge construction, tunnel construction, retaining wall construction, culvert construction and implemented BIM based 3D-BIM Modeling quantity calculation. Structure work in which errors occurred in range between -6.28% ~ 5.17%. Especially, understanding of the problem and improvement of the existing 2D-CAD based of quantity calculation through rock type quantity calculation error in range of -14.36% ~ 13.07% of earthwork quantity calculation. It's benefit and applicability of BIM method in civil engineering. In addition, routine method for quantity of earthwork has the same error tolerance negligible for that of structure work. But, rock type's quantity calculated as the error appears significantly to the reliability of 2D-based volume calculation shows that the problem could be. Through the estimating quantity of earthwork based 3D-BIM, proposed method has better reliability than routine method. BIM, as well as the design, construction, maintenance levels of information when you consider the benefits of integration, the introduction of BIM design in civil engineering and the possibility of applying for the effectiveness was confirmed. In addition, as the beginning phase of information integration, quantity document automation program has been developed for activation of BIM. And automatically enter the program code number, linkage and manual volume calculation program, quantity document automation programs, such as the development is now underway, and step-by-step procedures and methods are presented.