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Two-Dimensional Shape Description of Objects using The Contour Fluctuation Ratio (윤곽선 변동율을 이용한 물체의 2차원 형태 기술)

  • 김민기
    • Journal of Korea Multimedia Society
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    • v.5 no.2
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    • pp.158-166
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    • 2002
  • In this paper, we proposed a contour shape description method which use the CFR(contour fluctuation ratio) feature. The CFR is the ratio of the line length to the curve length of a contour segment. The line length means the distance of two end points on a contour segment, and the curve length means the sum of distance of all adjacent two points on a contour segment. We should acquire rotation and scale invariant contour segments because each CFR is computed from contour segments. By using the interleaved contour segment of which length is proportion to the entire contour length and which is generated from all the points on contour, we could acquire rotation and scale invariant contour segments. The CFR can describes the local or global feature of contour shape according to the unit length of contour segment. Therefore we describe the shape of objects with the feature vector which represents the distribution of CFRs, and calculate the similarity by comparing the feature vector of corresponding unit length segments. We implemented the proposed method and experimented with rotated and scaled 165 fish images of fifteen types. The experimental result shows that the proposed method is not only invariant to rotation and scale but also superior to NCCH and TRP method in the clustering power.

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Development of underwater 3D shape measurement system with improved radiation tolerance

  • Kim, Taewon;Choi, Youngsoo;Ko, Yun-ho
    • Nuclear Engineering and Technology
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    • v.53 no.4
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    • pp.1189-1198
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    • 2021
  • When performing remote tasks using robots in nuclear power plants, a 3D shape measurement system is advantageous in improving the efficiency of remote operations by easily identifying the current state of the target object for example, size, shape, and distance information. Nuclear power plants have high-radiation and underwater environments therefore the electronic parts that comprise 3D shape measurement systems are prone to degradation and thus cannot be used for a long period of time. Also, given the refraction caused by a medium change in the underwater environment, optical design constraints and calibration methods for them are required. The present study proposed a method for developing an underwater 3D shape measurement system with improved radiation tolerance, which is composed of commercial electric parts and a stereo camera while being capable of easily and readily correcting underwater refraction. In an effort to improve its radiation tolerance, the number of parts that are exposed to a radiation environment was minimized to include only necessary components, such as a line beam laser, a motor to rotate the line beam laser, and a stereo camera. Given that a signal processing circuit and control circuit of the camera is susceptible to radiation, an image sensor and lens of the camera were separated from its main body to improve radiation tolerance. The prototype developed in the present study was made of commercial electric parts, and thus it was possible to improve the overall radiation tolerance at a relatively low cost. Also, it was easy to manufacture because there are few constraints for optical design.

A Study on the Application of Line Array Roll Set Process to Shipbuilding Industry (선형 배열 롤 셋 공정의 조선 산업 적용에 관한 연구)

  • Shim, D.S.;Yang, D.Y.;Chung, S.W.;Han, M.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.10a
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    • pp.289-292
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    • 2009
  • The line array roll set process, as one of many kinds of incremental forming processes, is a continuous process in which a flat metal plate is formed into a singly or doubly curved plate through successive passes of forming rolls. It was found that the curvature level of the formed plates in the previous study was well over the curvature required in shipyards. This fact shows that the LARS method has considerable potential for shipbuilding applications. In a shipbuilding yard, hull forming is an important fabrication process in which flat plates are deformed into singly or doubly curved plates. The major purpose of the present study is to estimate experimentally the general applicability of the line array roll set process for the manufacture of ship hull plates. In this study, the target shapes are selected through investigation of the shape classification of ship hull plates that comprise a certain vessel. Forming processes for twisted shapes are analyzed with the finite element method (FEM). Finally, the results of experimental work for two types of target shapes are presented.

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Studies on the Mackerel Purse Seine Operation in the Sea Area of Cheju Island - 1 . Model Experiment on the Changes of Net Shape in Stagnant Water - (제주도 주변해엽 고등어 포착망의 연구 - 1 . 정수에 있어서 망형 변화에 관한 모형실험 -)

  • 박정식
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.22 no.2
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    • pp.7-15
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    • 1986
  • In order to investigate the performance for the mackerel purse seine of one boat purse seiner using in the sea area of Cheju Island, a model net is made of the scale of 1/400 of its full scale, and model test on the shape of net and the tension of purse line is carried out in the stagnant water channel of the circulating water tank. Designing and testing for the model net are based on the Tauti's law. The obtained results are as follows; 1. The sinking rate of net is maximized the value of 6.40 m/min from 5 to 10 minutes after shooting net, and the mean value is 6.13 m/min. 2. The enclosed area formed with the float line after pursing operation is 76-84% of the area which is formed immediately after the shooting operation. At that time, purse seine is pulled inward the circle of surrounding net about 26.5% of the diameter. 3. In operating, when longitudinal section area of the central part of the net is maximized, the split area of both the wing-ends is 31-32% of the former. 4. When the time for the completing of pursing is 20 minutes, the maximum tension of the purse line is about 10.2 tons.

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A Study on the Components and Characteristics of Hotel Access Space (호텔 진입공간의 구성요소 및 특성에 관한 연구)

  • Lee, Jeong-Lim;Kim, Yun-Hag;Cho, Yong-Joon
    • Journal of the Korean housing association
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    • v.20 no.4
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    • pp.1-9
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    • 2009
  • In this study, an examination and an analysis are carried out on the forms and components of the access spaces of hotel entrances from the front gate of five star hotels in Jejudo, Korea. The results of the study are as follows. In terms of the arrangement of the hotel, city hotels with a relatively narrow site area are influenced by site shape, while resort hotels with a relatively wide site area are affected by the environment. However, the location of the front gate was determined by the access road from the outside. Therefore, forms of access space are related to the front gate, which is governed by the access road, and to the entrance, which is determined by the hotel arrangement. If the front gate is in line with the hotel entrance, a straight line and the hotel are arranged vertically to the front gate(side arrangement) or the hotel is arranged horizontally to the front gate, but if the entrance is not in line with the front gate, it appears as a curved shape. However, those who use their own cars have a variety of choices for access route depending on the location of the parking lot.

Development of Men's suit Easy-Order Prototype using Cyber Fitting 3D Avatar (Cyber Fitting형 3D 아바타를 활용한 신사복 이지오더(Easy-Order) 프로토타입(Prototype) 개발)

  • Lim, Ji-Young
    • Fashion & Textile Research Journal
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    • v.11 no.2
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    • pp.308-314
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    • 2009
  • In creating an avatar, consumers can find out for themselves their own sizes to be entered. Also, putting in a face creation main-page menu option enables clients to make up their faces and match them to their bodies. Through this process when purchasing clothes through the internet consumers can enter their own body sizes and create avatars that are identical to their body shape. The uniqueness of developed prototype is that it creates an avatar similar to one's body shape according to body size inputs and demonstrates visually to customers the on-line comfort test which was only available off-line traditionally. The avatar follows the movement of mouse from left to right which enables 3 dimensional visualization. Through maximizing the visual effect this research focuses on enabling consumers to feel subjective parts as if they are off-line. This study seeks to provide a type of prototype of an online shopping mall that meets the demand of the consumers using the 3D avatar.

Y2BaCuO4 Segregarion , a Possibility of Multi-Seeding and the Origin of Diagonal Line in YBa2Cu3O7-$\delta$ Superconductor Single Crystal (YBa_{2}Cu_{3}O_{7-\delta} 고온초전도체 단결정에서의 Y_{2}BaCuO_{5} 편석과 Multi-Seeding의 가능성, 대각선 흔적의 형성 원인)

  • 성현태
    • Progress in Superconductivity and Cryogenics
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    • v.1 no.1
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    • pp.1-6
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    • 1999
  • The microstructures of top seed mult processde $\textrm{YBa}_2\textrm{Cu}_3\textrm{O}_7$.$\delta$ single crystal were studied. Although shape of the seed was not faceted. the growth shape of Y123 single crystal was faceted. It was observed that Y211 phases were trapped in specific spaces of the faceted region. From the microstructural investigation. it was suggested that the segregation of Y211 is due to the difference of growth rates in crystal direction. When a single crystal was grown by the single seed with stepped multi surfaces. a microstrue was grown from multi-seed. The microstructure show the possibility of multi-seed growth. Corn kernel like structure without Y211 phase was observed and seemed to be formed by the diffusion reaction between Y211 phase in crystal and liquid wetted on the crystal. the diagonal line on Y123 crystal was observed that it was formed by the corn kernel like structure.

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Most suitable design method of post-chlorination process in portable water process by using CFD (전산유체를 활용한 정수공정에서 후염소 투입공정 최적설계 방안)

  • Cho, Youngman
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.3
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    • pp.331-337
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    • 2013
  • Post-chlorination for disinfection in portable water process is final process. The design factors of post-chlorination are inflow pipe line from tank of filtrated water to cleanwell, injection point of chlorine, appropriate shape of baffle in cleanwell for disinfection efficient improvement. Until now, we did not have the design standard for post-chlorination. we evaluated most suitable design method of post-chlorination process in portable water process by using computational fluid dynamics in this research. We found the result that the pipe to connect the cleanwell should be one. If pipe line split into two or more, uniform distribution of the flow is difficult. Second, optimal injection point of chlorine is the middle of pipe line to connect the cleanwell. Therefore, it is not economical to install chlorine contact basin in cleanwell. Third, the shape of baffle should be designed in order to water flows in one direction. And we found that it is better to design the low number of flow turning.

An Investigation into the Three-dimensional Design of Turbine Rotor Blade for Turbopump (터보펌프용 터빈 로터 블레이드의 3차원 설계 연구)

  • Jeong, Sooin;Choi, Byoungik;Lee, Hanggi;Kim, Kuisoon
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.1038-1044
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    • 2017
  • We are working on improving the performance by applying the three-dimensional design element to the rotor blades of high pressure supersonic impulse turbine that drives turbo pump of liquid rocket engine. In this paper, based on the shape of a rotor blade of a turbopump turbine designed in the past, a three-dimensional shape is applied to a rotor blade through a stacking line change such as sweep and dihedral. After performing the flow analysis, the changes in the turbine performance characteristics for each design element were carefully examined and the results were summarized.

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A Study on the Application of Line Array Roll Set Process for the Manufacture of Real Ship Hull Plates (실선체 곡면 제작을 위한 선형 배열 롤 셋 공정의 적용에 관한 연구)

  • Shim, D.S.;Yang, D.Y.;Chung, S.W.;Han, M.S.
    • Transactions of Materials Processing
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    • v.19 no.2
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    • pp.120-126
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    • 2010
  • The line array roll set(LARS) process, as one of many kinds of incremental forming processes, is a continuous process in which a flat metal plate is formed into a singly or doubly curved plate through successive passes of forming rolls. It was found that the curvature level of the formed plates in the previous study was well over the curvature required in shipyards. This fact shows that the LARS method has good potential for shipbuilding applications. The major purpose of the present study is to estimate experimentally the general applicability of the line array roll set process for the manufacture of ship hull plates. In this study, the target shapes are selected through investigation of the shape classification of ship hull plates that comprise a certain vessel. Forming processes for twisted shapes are analyzed with the finite element method(FEM) and the results of experimental work are presented. On the basis of the experimental and numerical results, the LARS process is applied to the production of real outer hull plates of a small patrol ship.