• 한국CDE학회논문집
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• 제14권6호
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• pp.415-423
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• 2009

Because of the fast changing car design and increasing facilities, manufacturing process of cars is getting more complex now a days. Particularly, car manufacturing system that consist of automated devices, applies various simulation techniques to validate device motion and detect collision. To cope with this problem, traditional manufacturing system deployed test-run with the real devices. However, increased computing power in a contemporary manufacturing system changes it into realistic 3D simulation environment. Similarly, managed device data that was generated using 2D traditionally, can be converted to 3D realistic simulation. The existing problem with 3D simulation is disjoint data interaction between different work stations. Consequently, JIGs, fixing the car part accurately, are changed according to fixing position on the part or a part shape properties. In practice, the 3D JIG data has to be managed according to kinematic information, but not of its features. However, generating kinematic information to the 3D model repeatedly according to frequent change in part is not explained in current literatures. To fill this knowledge gap, this paper suggests an improving method of rendering 3D JIG kinematics information to simulation model. Thereafter, it shows the result of implementation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.26-29
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• 2003

UV laser micromachining are generally used to create microstructures for micro product through a sequence of lithography-based photopatterning steps. However, the micromachining process is not suitable for the rapid realization of complex microscale 3D product because it depends on worker experiences, excessive cost and time to make many masks. In this paper, the more effective micro rapid manufacturing process, which is developed upon the base of laser micromachining. is proposed to fabricate micro products directly using UV laser ablation and phase change filling. The filling process is useful to hold the micro product during the next ablation step. The proposed micro rapid manufacturing process is also proven experimentally that enables to fabricate the 3D microscale products of UV sensitive polymer from 3D CAD data to functional micro parts.

• 한국정밀공학회지
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• 제22권11호
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• pp.196-201
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• 2005

UV laser micromachining are generally used to create microstructures for micro product through a sequence of lithography-based photopatterning steps. However, the micromachining process is not suitable for the rapid realization of complex 3D micro product because it depends on worker experiences, excessive cost and time to make many masks. In this paper, the more effective micro rapid manufacturing process, which is developed upon the base of laser micromachining, is proposed to fabricate micro products directly using UV laser ablation and phase change filling. The filling process is useful to hold the micro product during the next ablation step. The proposed micro rapid manufacturing process is also proven experimentally that enables to fabricate the 3D micro products of UV sensitive polymer from 3D CAD data to functional micro parts.

• 한국정밀공학회지
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• 제21권7호
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• pp.30-36
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• 2004

Recently, the lead-time of a product is to be shortened in order to satisfy consumer's demand. It is thus important to reduce the manufacturing time and the cost of 3D-shaped microstructures. Micro-Electro-Mechanical Systems (MEMS) and devices are usually fabricated by lithography-based methods. Above method is not flexible for the rapid manufacture of 3D-shaped microstructures because it depends on work's experiences and requires excessive cost and time for making many masks. In this paper, the effective laser micrornachining is developed to fabricate UV sensitive polymer microstructures using laser ablation. The proposed process, named by laser microRP, is a very useful method on rapid manufacturing for 3D-shaped microstructures.

• International Journal of CAD/CAM
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• 제6권1호
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• pp.3-8
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• 2006

The application of three-dimensional (3-D) CAD has been popularized for design and production and digital manufacturing has been spreading in many industrial fields. By simulation of the production process using 3-D digital models, which are the core of CIM (Computer Integrated Manufacturing) system, the efficiency and safety of production are improved at each stage of work, and optimization of manufacturing can be achieved. This paper firstly describes the concept of "simulation based production" in shipbuilding and also digital manufacturing; the 3-D CAD system is indispensable for effective simulation because ship structure is three dimensionally complex. By simulation, "computer optimized manufacturing" can be possible. The most effective fields of simulation in shipbuilding are in jobs where many parties have to cooperate, while existing two-dimensional drawings are hardly observed the whole structures due to interference between structures or equipment of complex shape. In this paper some examples of the successful application in IHIMU (IHI Marine United Inc.) are shown: assembly of a pipe unit, erection of a complex hull block, carriage of equipment, installation of a propeller, and access in an engine room.

• 한국초전도ㆍ저온공학회논문지
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• 제24권1호
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• pp.8-12
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• 2022

Recently, research on applying composite materials to various industrial fields is being actively conducted. In particular, composite materials fabricated by Fused Deposition Modeling 3D printers have more advantages than existing materials as they have fewer restrictions on manufacturing shape, reduce the time required, weight. With these advantages, it is possible to consider utilizing composite materials in cryogenic environments such as the application of liquid oxygen and liquid hydrogen, which are mainly used in an aerospace and mobility. However, FDM composite materials are not verified in cryogenic environments less than 150K. This study evaluates the characteristics of composite materials such as tensile strength and strain using a UTM (Universal Testing Machine). The specimen is immersed in liquid nitrogen (77 K) to cool down during the test. The specimen is fabricated using 3D print, and can be manufactured by stacking reinforced fibers such as carbon fiber, fiber glass, and aramid fiber (Kevlar) with base material (Onyx). For the experimental method and specimen shape, international standards ASTM D638 and ASTM D3039 for tensile testing of composite materials were referenced.

• Current Optics and Photonics
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• 제7권6호
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• pp.638-654
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• 2023

Holography is generally known as a technology that records and reconstructs 3D images by simultaneously capturing the intensity and phase information of light. Two or more interfering beams and illumination of this interference pattern onto a photosensitive recording medium allow us to control both the intensity and phase of light. Holography has found widespread applications not only in 3D imaging but also in manufacturing. In fact, it has been commonly used in semiconductor manufacturing, where interference light patterns are applied to photolithography, effectively reducing the half-pitch and period of line patterns, and enhancing the resolution of lithography. Moreover, holography can be used for the manufacturing of 3D regular structures (3D photonic crystals), not just surface patterns such as 1D or 2D gratings, and this can be broadly divided into (i) holographic recording and (ii) holographic lithography. In this review, we conceptually contrast two seemingly similar but fundamentally different manufacturing methods: holographic recording and holographic lithography. We comprehensively describe the differences in the manufacturing processes and the resulting structural features, as well as elucidate the distinctions in the diffractive optical properties that can be derived from them. Lastly, we aim to summarize the unique perspectives through which each method can appear distinct, with the intention of sharing information about this field with both experts and non-experts alike.

• 센서학회지
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• 제31권5호
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• pp.279-285
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• 2022

Recently, 3D printing technology has gained increased attention in the manufacturing industry because it allows the manufacturing of complex but sophisticated structures as well as moderate production speed. Owing to advantages of 3D printers, such as flexible design, customization, rapid prototyping, and ease of access, can also be advantageous to sensor developments, 3D printing demands have increased in various active device fields, including sensor manufacturing. In particular, 3D printing technology is of significant interest in tactile sensor development where piezoelectric materials are typically embedded to acquire voltage signals from external stimuli. In regard with piezoelectricity, researchers have worked with various piezoelectric materials to achieve high piezoelectric response, but the structural approach is limited because ceramics have been regarded as challenging materials for complex design owing to their limited manufacturing methods. If appropriate piezoelectric materials and approaches to design are used, sensors can be fabricated with the improved piezoelectric response and high sensitivity that cannot be found in common bulk materials. In this study, various 3D printing technologies, material combinations, and applications of various piezoelectric sensors using the 3D printing method are reviewed.

• 한국기계가공학회지
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• 제15권2호
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• pp.38-45
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• 2016

Since a 5-axis machine tool has two rotary axes, it offers numerous advantages, such as flexible accessibility, longer tool life, better surface finish, and more accuracy. Moreover, it can conduct whole machining by rotating the rotary feed axes while setting the fixture at once without re-fixing in contrast to conventional 3-axis machining. However, it is difficult to produce complicated products that have a hollow shape. In contrast, 3D printing can produce an object with a complicated hollow shape easily and rapidly. However, because of layer thickness and shrinkage, its surface finish and dimensional accuracy are not adequate. Therefore, this study proposes hybrid technology by integrating the advantages of these two manufacturing processes. 3D printing was used as the additive manufacturing rapidly in the whole body, and 5-axis machining was used as the subtractive manufacturing accurately in the joining and driving places. The reliability of the proposed technology was verified through a comparison with conventional technology in the aspects of processing time, surface roughness. and dimensional accuracy.

• 대한치과보철학회지
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• 제55권4호
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• pp.436-443
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• 2017

과거의 computer-aided design/computer-aided manufacturing (CAD/CAM) 기술 형태는 사용자가 한 제조사의 구성요소만 사용해야 하는 폐쇄적인 시스템이었다면, 현재는 여러 제조사의 구성요소 중 사용자가 필요에 맞는 구성요소를 선택해서 사용할 수 있는 유연성을 가진 개방적인 시스템 형태로 변화하였다. 치과재료와 보철물 제작 기술의 발전에도 불구하고 의치 제작은 지난 100년 가까이 전통적인 제작방식을 따랐다. 하지만 최근 들어 기존 의치 제작의 단점을 보완하고자 CAD/CAM 제작 의치에 관한 연구가 활발히 이루어지고 있으며, 밀링이나 3D 프린팅을 이용해 상용화된 형태의 CAD/CAM 제작 의치가 이미 임상에서 쓰이고 있다. 본 증례는 3D face scan을 활용한 CAD/CAM 의치 제작의 가능성을 확인하고, CAD/CAM과 전통적인 방법으로 제작한 의치를 비교한 결과에 대해 보고하고자 한다.