• 제목/요약/키워드: Reverse design

검색결과 799건 처리시간 0.026초

HTS 케이블 냉각용 역브레이튼 사이클 극저온 냉동기 설계에 관한 연구 (Design of Reverse Brayton Cycle Cryocooler System for HTS Cable Cooling)

  • 박재홍;권용하;김영수;박성출
    • 한국초전도ㆍ저온공학회논문지
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    • 제5권2호
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    • pp.58-65
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    • 2003
  • The high temperature superconductivity(HTS) cable must be cooled below the nitrogen liquefaction temperature to applicate the cable in power generation and transmi-ssion system under the superconducting state. To obtain superconducting state. a reliable cryocooler system is required. Structural and thermal design have been performed to design cryocooler system operated with reverse Brayton cycle using gas neon as refrigerant. This cryocooler system consists of compressor. recuperator. coldbox. control valves and has 1 kW cooling capacity. Heat loss calculation was conducted for the given cryocooler system by considering the conduction and radiation through the multi-layer insulation(MLI) and high vacuum. The results can be summarized as: conduction heat loss is 7 W in valves and access port and radiation heat loss is 18 W through the surface of cryocooler. The full design specifications were discussed and the results were applied to construct in house HTS cable cooling system.

3차원 이미지 스캔 기반 MEP 시설물 관리 기술 연구 (Study on 3D Image Scan-based MEP Facility Management Technology)

  • 강태욱
    • 한국BIM학회 논문집
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    • 제6권4호
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    • pp.18-26
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    • 2016
  • Recently, for the purpose of maintenance of facilities and energy, there have been growing cases of the 3D image scan-based reverse design technology mostly in the manufacturing field. In the MEP field, because of differences between design and physical model, the reverse technology has been utilized in factory facilities such as a semiconductor factory. Because 3D point clouds from scanning include accurate 3D object information, the efficiency of management works related to the complex MEP facilities can be enhanced. In this study, the reverse technology was surveyed, and the MEP facility management based on 3D image scanning was analyzed. Based on the results, a method of 3D image scan-based MEP facility management was proposed.

사례 연구 - 3차원 역설계를 이용한 휴대폰 보호 커버 설계 (Case study - Design a cell phone cover by using reverse engineering)

  • 김대준;성진호;정성대;정연찬
    • Design & Manufacturing
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    • 제6권1호
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    • pp.29-33
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    • 2012
  • A 3D scanner scans and captures the shape of a real-world object. The captured shape can be used to construct three-dimensional model for CAD/CAM applications. In this study we have tried to design a cell phone cover by using the 3D scanner and reverse engineering. A 3D scanner is used to capture the shape of a cell phone. The 3D scanner generates a point cloud as the shape information. A three-dimensional CAD model for the cell phone is constructed from the point cloud. A cell phone cover is designed based on the CAD model of the cell phone. To check the integrity of this design process a prototype of the cover is made and assembled with the cell phone.

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Comparative analysis of internal flow characteristics of LBE-cooled fast reactor main coolant pump with different structures under reverse rotation accident conditions

  • Lu, Yonggang;Wang, Xiuli;Fu, Qiang;Zhao, Yuanyuan;Zhu, Rongsheng
    • Nuclear Engineering and Technology
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    • 제53권7호
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    • pp.2207-2220
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    • 2021
  • Lead alloy is used as coolant in Lead-based cooled Fast Reactor (LFR). The natural characteristics of lead alloy are combined with the simple structural design of LFR. This constitutes the inherent safety characteristics of LFR. The main work of this paper is to take the main coolant pump (MCP) in the lead-cooled fast reactor (LFR) as the research object, and to study the flow pattern distribution of the internal flow field under the reverse rotation pump condition, the reverse rotation positive-flow braking condition and the reverse rotation negative-flow braking condition. In this paper, the double-outlet volute type and the space guide vane are selected as the potential designs of the CLEAR-I MCP. In this paper, the CFD method is used to study the potential reverse accident of the MCP. It is found that the highest flow velocity in the impeller appears at the impeller outlet, and the Q-H curves of the two design programs basically coincide. The space guide vane type MCP has better hydraulic performance under the reverse rotation positive-flow condition, the Q-H curves of the two designs gradually separate with increasing flow rate, and the maximum flow velocity inside the space guide vane type MCP is obviously lower than that of the double-outlet volute type. For the reverse rotation test of MCP, only the condition of the forward rotating pump of the main coolant pump is tested and verified. For the simulation of the MCP in LBE medium, it proved that the turbulence model and basic settings selected in the simulation are reliable.

FFS 모드에서 러빙 방향에 따른 Reverse Twist 변화에 대한 연구 (Study on the Reverse Twist According to the Rubbing Direction for the Fringe-Field Switching (FFS) Mode)

  • 김미숙;신승민;정연학;김향율;김서윤;이승희
    • 한국전기전자재료학회논문지
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    • 제19권2호
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    • pp.185-188
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    • 2006
  • We studied on the reverse twist near the pixel edge depending on the rubbing direction for the fringe field switching (FFS) mode. Liquid crystal (LC) dynamic and the transmittance near the pixel edge, where the various field directions are generated, depend on the initial rubbing direction because the position of reverse twist is decided by the angle between the electric direction and the LC director at a bias voltage. For example, when the rubbing angle is $7^{\circ}$, the reverse twist appears on the bottom position of the right sharp comer of the pixel edge so that the reverse region exists far away from main active region. But, when the rubbing angle is $-7^{\circ}$, the reverse twist appears on the top position of the right sharp comer of the pixel edge, resulting that the region becomes more close to the main active area and the unstable disclination lines (DLs) easily intrude into the active region. Therefore, it is necessary to keep the reverse twist region far from the active region and it is possible by controlling the rubbing direction in the design of a pixel electrode.

Isolated Musculocutaneous Nerve Palsy after the Reverse Total Shoulder Arthroplasty

  • Kim, Sung-Guk;Choi, Chang-Hyuk
    • Clinics in Shoulder and Elbow
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    • 제19권2호
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    • pp.101-104
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    • 2016
  • Reverse total shoulder arthroplasty has been performed with promising results in rotator cuff tear arthropathy. However, the global complication of the reverse total shoulder arthroplasty is relatively higher than that of the conventional total shoulder arthroplasty. Neurologic complications after reverse total shoulder arthroplasty are rare but there are sometimes remaining sequelae. The cause of the neurologic complication is multifactorial, including arm traction, position and the design of the implant. Most cases of neurologic palsy following reverse total shoulder arthroplasty occur in the axillary nerve and the radial nerve. The authors report on a case of a 71-year-old man with isolated musculocutaneous nerve palsy after reveres total shoulder arthroplasty with related literature.

New Geometric modeling method: reconstruction of surface using Reverse Engineering techniques

  • Jihan Seo
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 1999년도 추계학술대회
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    • pp.565-574
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    • 1999
  • In reverse engineering area, it is rapidly developing reconstruction of surfaces from scanning or digitizing data, but geometric models of existing objects unavailable many industries. This paper describes new methodology of reverse engineering area, good strategies and important algorithms in reverse engineering area. Furthermore, proposing reconstruction of surface technique is presented. A method find base geometry and blending surface between them. Each based geometry is divided by triangular patch which are compared their normal vector for face grouping. Each group is categorized analytical surface such as a part of the cylinder, the sphere, the cone, and the plane that mean each based geometry surface. And then, each based geometry surface is implemented infinitive surface. Infinitive average surface's intersections are trimmed boundary representation model reconstruction. This method has several benefits such as the time efficiency and automatic functional modeling system in reverse engineering. Especially, it can be applied 3D scanner and 3D copier.

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Generalized Vehicle Routing Problem for Reverse Logistics Aiming at Low Carbon Transportation

  • Shimizu, Yoshiaki;Sakaguchi, Tatsuhiko
    • Industrial Engineering and Management Systems
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    • 제12권2호
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    • pp.161-170
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    • 2013
  • Deployment of green transportation in reverse logistics is a key issue for low carbon technologies. To cope with such logistic innovation, this paper proposes a hybrid approach to solve practical vehicle routing problem (VRP) of pickup type that is common when considering the reverse logistics. Noticing that transportation cost depends not only on distance traveled but also on weight loaded, we propose a hierarchical procedure that can design an economically efficient reverse logistics network even when the scale of the problem becomes very large. Since environmental concerns are of growing importance in the reverse logistics field, we need to reveal some prospects that can reduce $CO_2$ emissions from the economically optimized VRP in the same framework. In order to cope with manifold circumstances, the above idea has been deployed by extending the Weber model to the generalized Weber model and to the case with an intermediate destination. Numerical experiments are carried out to validate the effectiveness of the proposed approach and to explore the prospects for future green reverse logistics.

3D scanner 와 VisualLISP을 이용한 3차원 모델링에 관한 연구 (A Study on 3D modeling using a 3D scanner and VisualLISP)

  • 김세민;이승수;김민주;장성규;전언찬
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.410-413
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    • 2001
  • This paper is to model a 3D-shape product applying mathematically the data acquired from a 3D scanner and using an Automatic Design Program. The research studied in the reverse engineering up to now has been developed continuously and surprisingly. However, forming 3D-shape solid models in CAE and CAM, based on the research, the study leaves much to be desired. Especially, analyses and studies reverse-designing automatically using measured data after manufacturing. Consequently, we are going to acquire geometric data using an 3D scanner in this study with which we will open a new field of reverse engineering by a program whic hcan design a 3D-shape solid model in a CAD-based program automatically.

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LSC를 이용한 스캔데이터 변환 및 3차원 모델 생성에 관한 연구 (A Study on the 3D Modelling and Transference of Scaning Data using LSC Method)

  • 김민주;이승수;박정보;김순경;전언찬
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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    • pp.387-392
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    • 2001
  • This paper is to model a 30-shape product applying mathematically the data acquired from a 3D scanner and using an Automatic Design Program. The research studied in th reverse engineering up to now has been developed continuously and surprisingly. However, forming 3D-shape solid models in CAE and CAM, based on the research, the study leaves much to be desired. Especially, analyses and studies reverse-designing automatically using measured data after manufacturing. Consequently, we are going to acquire geometric data using an 3D scanner in this study with which we will open a new field of reverse engineering by a program which can design a 3D-shape solid model in a CAD-based program automatically.

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