• Journal of the Korean Society of Industry Convergence
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• v.16 no.3
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• pp.85-93
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• 2013

The MCT has been most extensively used in the machining. In particular, the ball endmill has been mainly adopted for finishing on the free- form surface. The advancement of CAD/CAM software has made it possible to develop various cutting pattern methods and to create diverse tool routes. Therefore, the current research made an attempt to find the optimal cutting pattern among the seven cutting patterns (i.e., Follow Periphery, Zig, Zig Zag, Concentric Zig, Concentric Zig Zag, Radial Zig, Radial Zig Zag) when aluminium 6000 series were machined by the ball endmill. The optimal pattern was found by comparing different shapes and surface roughness produced by the seven patterns. The current research found that each cutting pattern produced its own unique geometric features on the machined surface. It was found that the Radial Zig cutting pattern produced the lowest roughness on the flat surfaces. The Radial Zig Zag cutting pattern was found to produce the most accurate free-form surface. Finally, the most efficient cutting pattern in terms of machining time turned out to be the Follow Periphery.

• International Journal of CAD/CAM
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• v.9 no.1
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• pp.121-128
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• 2010

The purpose of this study is to clarify the mechanical behavior of human lumbar vertebrae (L3/L4) with and without fusion bone under physiological axial compression. The author has developed the program code to build the patient specific three-dimensional geometric model from the computed tomography (CT) images. The developed three-dimensional model provides the necessary information to the physicians and surgeons to visually interact with the model and if needed, plan the way of surgery in advance. The processed data of the model is versatile and compatible with the commercial computer aided design (CAD), finite element analysis (FEA) software and rapid prototyping technology. The actual physical model is manufactured using rapid prototyping technique to confirm the executable competence of the processed data from the developed program code. The patient specific model of L3/L4 vertebrae is analyzed under compressive loading condition by the FEA approach. By varying the spacer position and fusion bone with and without pedicle instrumentation, simulations were carried out to find the increasing axial stiffness so as to ensure the success of fusion technique. The finding was helpful in positioning the fusion bone graft and to predict the mechanical stress and deformation of body organ indicating the critical section.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.6
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• pp.41-46
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• 2017

Productivity improvement and cost reduction in the aircraft industry have become major industrial objectives, and improving productivity by reducing machining time has become a key focus. When numerical cutting code is created by CAM software, such as CATIA or UG-NX, it is impossible to control machining feed speed using cutting force changes depending on the machining tool path. However, machining an aircraft engine part from difficult material, such as Inconel 718, takes a long time, and tool chipping or breakage often occurs from forcing the machining path too quickly. This study investigated and verified the reliability of the AdvantEdge production module (PM)using cutting power tests. In particular, diffuser and diffuser case parts were considered, comparing cutting power and machining time using AdvantEdge PM and CATIA.

• Korean Journal of Computational Design and Engineering
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• v.8 no.2
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• pp.115-121
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• 2003

A new Layered Manufacturing(LM) system, named PaperMill, is developed applying micro milling technology. A micro endmill(127 11m in diameter) is introduced as the cutter of build material. The selected build material for this system is an adhesive-coated paper roll which provides advantages such as good bonding between layers, machinability, and low material cost. A 3-axis CNC controller and three step-motors are used for the movement of X-Y-Z table of the system. For simplicity of the control of mechanism, the control system for feeding the paper roll is uncoupled from CNC controller. Two code converters are developed for the toolpath generation of the new LM system. The NC converter generates a set of NC codes for PaperMill using commercial CAM software while the SML converter generates an NC code from Quickslice's SML format. The NC codes generated from the converters consist of a series of profile data and trigger code for paper feeding. Two sample gears were fabricated to prove the concept of the system, which shown that the dimensional errors of the fabricated gears is under 3.4 percent.

• International Journal of CAD/CAM
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• v.1 no.1
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• pp.1-9
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• 2002

The STL or Stereolithography format, established by 3D systems, gathers the geometric data of the model in a number of triangular surfaces. It can be in ASCII or binary format, and is a de facto standard in the Rapid Prototyping (RP) world. RP has developed greatly over the last ten years. In particular, improvement in materials has meant greater part accuracy and strength, which in turn has increased the range of functional applications. Future applications of RP will focus on rapid tooling and direct manufacturing. Direct manufacturing in particular may see much benefit from the incorporation of color into models. For color RP, besides designing new hardware to add color into the prototypes, it is necessary to redefine the CAD software for adding and accurately positioning color onto the model. STL cannot effectively store this kind of information. Among the existing data file formats, VRML is an acceptable one that is complimentary to existing RP processes. This paper acts as a review to discuss several methods of using VRML for coloring model data. This paper will also discuss the problems occurred in coloring the layer contours of the RP model.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.189-199
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• 2021

This study aimed to explore the factors affecting the innovation capacity of students at the National Economics University, Vietnam. Researchers used the innovation capacity model based on six factors, including personality traits, future orientation, creative skills, social interaction, content knowledge, and management skills. The empirical analysis used data from the survey of 303 students at National Economics University, Vietnam, with reliable tools (SPSS 26.0 software). The data were analyzed by testing the reliability of the scales, correlation analysis, and Pearson' Linear Correlation Coefficient, exploratory factor analysis, as well as regression model based on the survey data. The research results identified the following factors affecting innovation capacity of students: management skills, social interaction, and personality traits have the strongest impact on innovation capacity of students; content knowledge has the following strongest effects on innovation capacity of students; and finally the creative skills that affects on innovation capacity of students. There is also a positive relationship between all the factors and innovation capacity of students. The result can serve as useful reference sources for scholars who are interested in the innovation field. It also helps university's managers and policymakers build the appropriate environment to improve innovation capacity of students.

• Journal of Technologic Dentistry
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• v.41 no.1
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• pp.9-19
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• 2019

Purpose: This study was conducted to comparative evaluate the marginal and internal gap of three-unit metal frameworks(Co-Cr) fabricated by wax milling method and digital light projection method of CAD/CAM systems. Methods: All the specimens were fabricated by three different fabrication methods: conventional wax up with casting(CWC), milled wax block with casting(MWC), digital light projection with casting(DLPC) (n=10 each). The marginal and internal fits of specimens were examined using a replica technique. The light-body silicone thickness was measured at 8 reference points(each abutment: 16 measurements). All measurements were conducted by a stereomicroscope. Digital photo were taken at $150{\times}$ magnification and then analyzed using a measurement software. The Mann-Whitney test was used for analyzing the results. Results: Statistically significant differences were found between the fabrication methods(p<0.001). The mean(SD) is ${\mu}m$ for fabrication methods, the mean marginal fit were recorded respectively, CWC 63(38), MWC group 50(33), DLPC 103(54) and the mean internal fit CWC 96(47), MWC group 116(41), DLPC 138(66). Conclusion : The marginal and internal fit were statistically different according to the fabrication methods(p<0.001). In all fabrication methods, the greatest misfit was found the occlusal area of all specimens.

• The Journal of Advanced Prosthodontics
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• v.11 no.4
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• pp.232-238
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• 2019

PURPOSE. The aim of this study was to investigate simulated localized and generalized wear of indirect composite resins used for implant supported provisional restorations. MATERIALS AND METHODS. The study investigated ten indirect composite resins. Two kinds of wear were simulated by 400,000 cycles in a Leinfelder-Suzuki (Alabama) machine. Localized wear was simulated with a stainless-steel ball bearing antagonist and generalized with a flat-ended stainless-steel cylinder antagonist. The tests were carried out in water slurry of polymethyl methacrylate beads. Wear was measured using a Proscan 2100 noncontact profilometer in conjunction with Proscan and AnSur 3D software. RESULTS. Both localized and generalized wear were significantly different (P<.05) among the indirect composite resins. SR Nexco and Gradia Plus showed significantly less wear than the other indirect composite resins. The rank order of wear was same in both types of wear simulation. CONCLUSION. Indirect composite resins are recommended when a provisional implant-supported restoration is required to function in place over a long period. Although only some indirect composite resins showed similar wear resistance to CAD/CAM composite resins, the wear resistance of all the indirect composite resins was higher than that of bis-acryl base provisional and polymethyl methacrylate resins.

• The Research Journal of the Costume Culture
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• v.31 no.2
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• pp.213-227
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• 2023

To analyze the status and needs of the small- and medium-sized garment manufacturing industry in Busan, this study comprised an online survey of companies and interviews with 14 representatives of the 98 companies. The results are as follows: Approximately 34.7% of the garment manufacturers were located in Geumjeong-gu, Busan. The most common type of work was the contracting factory type. Daily production output was between 100pcs and 300pcs. Production materials comprised 42.9% woven and 24.8% knitted fabrics. Main products were menswear, uniforms, womenswear, casual wear, sports and leisure wear, protective clothes, and children's clothing. The main clients were uniform companies, main factories, wholesale markets, online shopping malls and promotion companies, exporters, and department stores. As a result of a survey on industrial needs with company representatives, their satisfaction with company employees was 57.2%, and the most important factor when hiring employees was job-related competencies, among which the ability to understand the sewing process was the most necessary. In terms of computer software literacy, illustrations and pattern CAD/CAM are required. They thought industry-university cooperation is crucial for advantage for advantage research and product development, as it allows for the sharing knowledge, resources, and especially human resources. The greatest administrative issue were human resources and funding.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.21-22
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• 2009

유비쿼터스 사회(Ubiquitous Society)로의 진입에 발맞추어 USN(Ubiquitous Sensor Network) 기반의 인간 중심적 편의 시스템에 관한 연구가 활발하게 진행되고 있다. 그 중 대형 시장을 갖는 차량 편의시설에 관한 연구는 지능형 차량 시스템(Intelligent Car System)을 중심으로 활발히 이루어지고 있다. 지능형 차량 시스템의 주요 연구는 자동 항법 장치, 사고 예방 장치, 자가 진단 시스템 등 탑승자의 편의성과 안전성을 중심으로 진행되었다. 그러나 탑승자의 사고 발생 시 응급 상황 처리를 위한 지원 시스템은 미미하다. 탑승자 부상으로 사고 신고를 하지 못할 경우, 사고지점 확인, 탑승자의 위급(현재) 상황, 부상 정보와 같은 정보를 얻을 수 없어 응급 상황 대처에 신속하지 못할 수 있다. 따라서 본 논문은 다양한 센서를 이용하여 차량의 정보를 수집하고, 사고 판단 시 차량 위치 정보, 탑승자 상황 정보를 응급 기관에 전달할 수 있는 차량용 스마트 안전장치를 설계 및 구현하였다. 테스트를 위해 Intel PXA255 MCU와 AM-3AXIS(3축 가속 센서), MDSM-1000A(지자기 센서), RX-M800S CDMA, GPS520, Alpha cam, Flex Sensor로 시스템을 제작하였으며 모의 도로 모형에서 테스트 하였다.