• Title/Summary/Keyword: arrangement of patterns

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Influence of Winding Patterns and Infiltration Parameters on Chemical Vapor Infiltration Behaviors of SiCf/SiC Composites (SiCf/SiC 복합체의 화학기상침착 거동에 미치는 권선 구조와 침착 변수의 영향)

  • Kim, Daejong;Ko, Myoungjin;Lee, Hyeon-Geun;Park, Ji Yeon;Kim, Weon-Ju
    • Journal of the Korean Ceramic Society
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    • v.51 no.5
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    • pp.453-458
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    • 2014
  • SiC and its composites have been considered for use as nuclear fuel cladding materials of pressurized light water reactors. In this study, a $SiC_f$/SiC composite as a constituent layer of SiC triplex fuel cladding was fabricated using a chemical vapor infiltration (CVI) process in which tubular SiC fiber preforms were prepared using a filament winding method. To enhance the matrix density of the composite layer, winding patterns, deposition temperature, and gas input ratio were controlled. Fiber arrangement and porosity were the main parameters influencing densification behaviors. Final density of the composites decreased as the SiC fiber volume fraction increased. The CVI process was optimized to densify the tubular preforms with high fiber volume fraction at a high $H_2$/MTS ratio of 20 at $1000^{\circ}C$; in this process, surface canning of the composites was effectively retarded.

Development of Localization and Pose Compensation for Mobile Robot using Magnetic Landmarks (마그네틱 랜드마크를 이용한 모바일 로봇의 위치 인식 및 위치 보정 기술의 개발)

  • Kim, Bum-Soo;Choi, Byung-June;You, Won-Suk;Moon, Hyung-Pil;Koo, Ja-Choon;Choi, Hyouk-Ryeol
    • The Journal of Korea Robotics Society
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    • v.5 no.3
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    • pp.186-196
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    • 2010
  • In this paper, we present a global localization and position error compensation method in a known indoor environment using magnet hall sensors. In previous our researches, it was possible to compensate the pose errors of $x_e$, $y_e$, ${\theta}_e$ correctly on the surface of indoor environment with magnets sets by regularly arrange the magnets sets of identical pattern. To improve the proposed method, new strategy that can realize the global localization by changing arrangement of magnet pole is presented in this paper. Total six patterns of the magnets set form the unique landmarks. Therefore, the virtual map can be built by using the six landmarks randomly. The robots search a pattern of magnets set by rotating, and obtain the current global pose information by comparing the measured neighboring patterns with the map information that is saved in advance. We provide experimental results to show the effectiveness of the proposed method for a differential drive wheeled mobile robot.

A Human Factors Study in Instrument Panel Layout of the Korean Air Force Aircraft. (항공기 계기판의 적정배열을 위한 인간공학적 연구)

  • Park Jong-Sun
    • Journal of the military operations research society of Korea
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    • v.2 no.1
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    • pp.127-143
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    • 1976
  • The purpose of this thesis is to study the optimal arrangement of aircraft instrument panels through the human factors approach. Human factors engineering is the process of effectively fitting the human component to the machine component in any man-machine system. The human factors. are especially important to an aircraft pilot who must constantly shift his attention between the instrument panel within the cockpit and the surrounding area of the aircraft. The preliminary part of this study is to find the general patterns of the Korean pilot's eye movements during their various flying maneuvers, and which instruments require the most attention while in flight. It is assumed that all pilots have a general pattern of eye movement when observing the aircraft instrument panel and that an optimum arrangement would be to minimize the eye travel distance between instruments. In this thesis the arrangements of instruments is taken to be the independent variable and the eye travel distance between instruments the dependent variable. la order to compile the information necessary for this study, sixty Korean Air Force pilots were interviewed and requested to complete information forms. These information forms listed various flying maneuvers and listed each instrument used on the instrument panel. The compilation of the information on these completed forms listed the instruments most frequently used by the pilots. The second part of this study was to determine the optimum instrument arrangement. It was necessary to study the various number of possible arrangements of instruments depending upon the number of instruments involved. Therefore, these instruments are grouped by two major functions, The flight instruments were subdivided into three groups, and the engineering instruments were subdivided into six groups. With this subdivision we arrive at the possible number of arrangements of 4,320. Through the simulation method, total eye travel distance for each of these 4,320 arrangements is calculated and the arrangement which appears to be of optimum distance between the most frequently used aircraft instruments is determined. The results of this study indicate that the optimum distance between instruments would be 33,028cm and that the corresponding distance of the instrument panel now being used is 34,288cm. Therefore, an increased efficiency of $3.8\%$ would be realized if the existing aircraft instrument panel were re-arranged according to layout proposed in this thesis.

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Studios on the Physical and Psychological Analysis in Street Spaces for Improving the Streetscape of Olympic Daero (올림픽대로의 경관향상을 위한 가로공간 구성요소의 물리량과 심리량 분석에 관한 연구)

  • 김광래;진희성
    • Journal of the Korean Institute of Landscape Architecture
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    • v.16 no.2
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    • pp.23-41
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    • 1988
  • Environmental design pattern of the nine Small Urban Spaces at C.B.D. in City of Seoul are surveyed and analyzed for user's satisfaction and behavior under the environmental design evaluation by using Chrisopher Alexander's Pattern Language. Small Urban Spaces as a part of streetscape are formed by physical factors as well as visual environment and interacting user's behavior. Therefore, user's satisfacuion and behavior at the nine Urban Small Spaces were investigated under the further search for some possibilities of a pplication of those Pattern Languages. A pattern language has a structure of a network. It is used in sequence, going through the patterns, moving always from large patterns to smaller, always from the ones which create comes simply from the obsernation that most of the wonderful places of the city were not made by architects but by the people. It defines the limited number of arrangements of spaces that make sense in any given culture. And it actually gives us the power to generate these coherent arrangement of space. As a results, 'Plazl', 'Seats' and 'Accessibility' related design patterns are highly evaluated by Pattern Frequency, Pattern Interaction and their Composition ranks, thus reconfirm Whyte's Praise of urban Small Spaces in our inner city design environments. According to the multiple regression analysis of user's evaluation, the environmental functins related to the satisfaction were 'Plaza', 'Accessibility' and 'Paving'. According to the free response, user's prefer such visually pleasing environmental design object as 'Waterscape' and 'Setting'. In addition to, the basic needs in Urban Small Spaces are amenity facilities as bench, drinking water and shade for rest.

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A taxonomic study on six sections Ischnostachyae, Anomalae, Capitellatae, Debiles, Capillares and Molliculae of Carex L. in Korea (Cyperaceae) (한국산 사초속 사초아속 (Carex subgen. Carex) 6절 식물의 분류학적 연구)

  • Oh, Yong Cha;Lee, Chang Shook;Yoon, Ja Young
    • Korean Journal of Plant Taxonomy
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    • v.34 no.4
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    • pp.297-319
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    • 2004
  • Morphological characters of 14 taxa in 6 sections Ischnostachya(one taxon), Anomalae(one taxon), Capitellatae (five taxa), Debiles (one taxon), Capillares (one taxon) and Molliculae (five taxa) of genus Carex (Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by using a scanning eletron microscope (SEM) and a light microscope (LM). Morphological characters such as rhizome, spike, width of leaf, leaf sheath, involucre, involucre sheath, beak of perigynium, perigynium shape, and leaf epidermal patterns were useful for the identification of observed fourteen taxa. The number of spike, arrangement of psitillate or staminate spike and presence of bract were very useful characters to divide the treated 14 taxa into two groups. A key based on data was presented here.

Development of Textile Design Combining K-pop star Symbols and Traditional Patterns - Focusing on BTS 'IDOL' - (K-pop 스타 상징물과 전통문양을 결합한 텍스타일디자인 개발 - BTS의 'IDOL' 중심으로 -)

  • Lee, Kyong-Soon;Choi, Yoon-Mi
    • Fashion & Textile Research Journal
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    • v.24 no.1
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    • pp.1-14
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    • 2022
  • K-pop stars are an important influence in the era of digital culture based on emotions. The purpose of this study is to visually express the identity and worldview of their music in the virtual and real world, and to promote Korea's current and past culture. The study also intends to appeal to the emotions of the global fans by designing original textile in their music video 'IDOL' on Tiny TAN - a symbol of world pop star BTS. For design development, traditional Korean images shown in the 'IDOL' video were collected, patterns for each member were selected, and a motif was designed on Adobe Illustrator. We selected the dragon as the motif for V, cloud for Suga, chrysanthemums for Jin, mask for Jung Kook, hanok pavilion for RM, fan for Jimin, and Sam Taegeuk for J-Hope. The selected motifs were designed as per the four textile design arrangement methods: square pattern, 1/2 half drop pattern, turn-around pattern, and panel pattern. The design was presented by mapping Kwaeja to Tiny TAN character. The developed textile design can be used not only for character costumes in virtual space, but also for various products such as clothes, accessories, bedding, cosmetics, stationery, and food. By using it to produce goods inspired by K-pop stars, it can be used as basic data for the development of high value-added competitive products in the global market and create synergy effects of K-Design, which would lead a new trend in the design world.

Reliability of numerical computation of pedestrian-level wind environment around a row of tall buildings

  • Lam, K.M.;To, A.P.
    • Wind and Structures
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    • v.9 no.6
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    • pp.473-492
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    • 2006
  • This paper presents numerical results of pedestrian-level wind environment around the base of a row of tall buildings by CFD. Four configurations of building arrangement are computed including a single square tall building. Computed results of pedestrian-level wind flow patterns and wind speeds are compared to previous wind tunnel measurement data to enable an assessment of CFD predictions. The CFD model uses the finite-volume method with RNG $k-{\varepsilon}$ model for turbulence closure. It is found that the numerical results can reproduce key features of pedestrian-level wind environment such as corner streams around corners of upwind building, sheltered zones behind buildings and channeled high-speed flow through a building gap. However, there are some differences between CFD results and wind tunnel data in the wind speed distribution and locations of highest wind speeds inside the corner streams. In locations of high ground-level wind speeds, CFD values match wind tunnel data within ${\pm}10%$.

Analysis of the Electric-field Characteristics of V/UHF Antennas Installed on a Shipboard (함정 탑재 V/UHF 안테나의 전계 특성 분석)

  • Lee, Jin-Ho;Kwon, Joon-Hyuck;Song, Ki-Hwan
    • Journal of the Korea Institute of Military Science and Technology
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    • v.11 no.6
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    • pp.74-80
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    • 2008
  • Analysis of the electromagnetic environment on topside of a ship is needed for optimal arrangement of all kinds of antennas to be installed on the shipboard in order to minimize the probability of EMI of equipment and subsystems in real ship after construction phase. In this paper we analyze the characteristics of electric-fields such as radiation patterns and near E-fields of V/UHF antennas installed on a shipboard. We compare simulated results with measurements on the real ship for near E-fields to verify the reliability of the computed electromagnetic environment. Although there are various factors causing errors such as cable loss and impedance mismatching etc. when measuring near E-field, both data show similar trends in the range of the acceptable tolerance.

Nanotransfer Printing for Large-Scale Integrated Nanopatterns of Various Single-Crystal Organic Materials

  • Baek, Jang-Mi;Park, Gyeong-Seon;Seong, Myeong-Mo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.361.2-361.2
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    • 2016
  • The manufacture of organic electronic circuits requires effective heterogeneous integration of different nanoscale organic materials with uniform morphology and crystallinity in a desired arrangement on a substrate. Herein, we present a new direct printing method, which enables monolithic integration of crystalline nanowire arrays with a diverse range of organic materials. In this method, we use a nanoscale patterned soft mold, which contains an assembly of simple nanoline patterns but, in combination with droplet of various organic inks, can produce a large-scale integration of various nanopatterns with multiple kinds of organic materials. The morphology of organic nanowires can controlled by nanoconfinement in nanoline of mold. And mutual alignment of nanopatterns can be controlled by adjusting the ink droplet size, number of droplets, ink deposition locations.

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Behavior of geotextile reinforced flyash + clay-mix by laboratory evaluation

  • Vashi, Jigisha M.;Desai, Atul K.;Solanki, Chandresh H.
    • Geomechanics and Engineering
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    • v.5 no.4
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    • pp.331-342
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    • 2013
  • The major factors that control the performance of reinforced soil structures is the interaction between the soil and the reinforcement. Thus it is necessary to obtain the accurate bond parameters to be used in the design of these structures. To evaluate the behavior of flyash + clay soil reinforced with a woven geotextile, 36 Unconsolidated-Undrained (UU) and 12 reinforced Consolidated-Undrainrained (CU) triaxial compression tests were conducted. The moisture content of soil during remolding, confining pressures and arrangement of geotextile layers were all varied so that the behavior of the sample could be examined. The stress strain patterns, drainage, modulus of deformation, effect of confinement pressures, effects of moisture content have been evaluated. The impact of moisture content in flyash + clay backfills on critical shear parameters was also studied to recommend placement moisture for compaction to MDD. The results indicate that geotextile reinforced flyash + clay backfill might be a viable alternative in reinforced soil structures if good-quality granular backfill material is not readily available.