• Title/Summary/Keyword: Cutting Direction

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Reliability-Based Analysis for Rock Slopes Considering Failure Modes (파괴형태를 고려한 암반사면의 신뢰도해석)

  • 이인모;이명재
    • Journal of the Korean Geotechnical Society
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    • v.15 no.6
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    • pp.3-16
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    • 1999
  • This paper presents the results of sensitivity analysis based on an example study to verify a newly developed reliability-based model for rock slopes considering uncertainties of discontinuities and failure modes-plane, wedge, and toppling. The parameters that are needed for sensitivity analysis are the variability of discontinuity properties (orientation and strength of discontinuities), the loading conditions, and the rock slope geometry. The variability in orientation and friction angle of discontinuities, which can not be considered in the deterministic analysis, has a great influence on the rock slope stability, The stability of rock slopes including failure modes is more influenced by the selection of dip direction of cutting rock face than any other design variables, The example study shows that the developed reliability-based analysis model can reasonably assess the stability of rock slope.

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The effect of retention grooves in Acrylic resin tooth denture base bond (합성수지 인공치와 열중합의치상 Resin의 결합시 인공치에 형성하는 유지공의 효과에 관한 연구)

  • Kim, Bu-Sob
    • Journal of Technologic Dentistry
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    • v.9 no.1
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    • pp.51-55
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    • 1987
  • One of the primary advantages of acrylic resin teeth is their ability to bond chemically to the denture base resins. Fracture od acrylic resin teeth from a maxillary denture, however, is not uncommon. Bonding failures have been attributed to faulty boil-out procedures that fail to eliminate all traces of wax from the ridge lap surfaces of the teeth and to contamination of the ridge lap surface by careless application of tinfoil substitute. Attempts to increase the strength of the bond between acrylic resin teeth and heat-cured denture base resin include grinding the glossy ridge lap surface (in fluid system), painting the ridgelap surface of the teeth with monomer-polymer solution, and cutting retention grooves in the ridge lap surface of the teeth. This latter method has been tested by applying a tensile force in a labial direction to the incisal part of the lingual surface of the acrylic resin teeth. A progressive shear compressive load was applied at an angle to the lingual surface of acrylic resin teeth bonded to denture base acrylic resin. No statistically singificant advantage was derived by preparing retention grooves of different shapes in the ridgelap surface of the denture teeth.

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Software Development for Automatic Generation of Unit Shape Part for Variable Lamination Manufacturing Process (가변 적층 쾌속 조형 공정 개발을 위한 단위형상조각 자동 생성 소프트웨어 개발 및 적용 예)

  • Lee, Sang-Ho;Kim, Tae-Hwa;An, Dong-Gyu;Yang, Dong-Yeol;Chae, Hui-Chang
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.8
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    • pp.64-70
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    • 2001
  • In all the Rapid Prototyping (RP) techniques, the computer-aided design (CAD) model of a three-dimensional part is sliced into horizontal layers of uniform, but not necessarily constant, thickness in the building direction. Each cross- sectional layer is successively deposited and, at the same time, bonded onto the previous layer. The stacked layers form a physical part of the model. The objective of this study is to develop a software for automatic generation of unit shape part(USP) for a new RP process, Variable Lamination Manufacturing using the linear hotwire cutting technique and expandable polystyrene foam sheet as part material(VLM-S). In order to examine the applicability of the developed software to VLM-S, USPs of general three-dimensional shapes, such as an auto-shift lever knob and a pyramid shape were generated.

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2-Dimensional Numerical Analysis of Crossing Tunnel under Railroad using Roof Panel Shield Method (RPS공법을 이용한 철도횡단터널의 2차원수치해석)

  • Shin, Eun-Chul;Roh, Jeong-Min;Lee, Eun-Soo;Kim, Kyeong-Mo;Kim, Jung-Hyi;Jung, Byung-Chul
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.10a
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    • pp.591-600
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    • 2005
  • There are many cross tunnelling methods such as NTR, TRCM, Messer Shield, Front Jacking, and Pipe Roof Method. The advantages of adopting RPS(roof panel shield) method in crossing tunnel construction with comparing other existing cross tunnelling method are needed a little space and easy to change the direction of cutting shoe during the construction of pipe roof. The numerical analysis of RPS was performed for the application in the crossing tunnel under railroad. The earth pressure distribution and settlement were predicted when the RPS method was applied during the excavation for crossing railroad tunnel construction.

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System Development for Automatic Tool Wear Measurement (자종공무마모계측시스템개발)

  • Kim, Y.I.
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.6
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    • pp.185-199
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    • 1994
  • This study has been performed to present a new automatic tool wear measurement by digital image processing. The purpose of this paper is to develop an automatic tool wear measuring system based on the image processing which can be applied to the quasi-real time measurement of the characteristics of insert tip in turning. Tool wear monitoring is one of the key-problems, for the development of control systems of modern unmanned factory which are not completely solved now. In oredr words at present complete qualitative and quantitative information on tool wear morphology is required, at least on the following aspects : flank wear, its dimensions and distribution on the maximum and mean values on VB pqrqmeter in the various zones of the wearland. crater wear, its main dimensions and values of KT parameters. This research has been performed to this technique made possible by designing a proper lighting system to the worn tool with following features : The flank wear is measured by observing the active cutting part from a proper direction and by lighting the wearland by a diffuser optic system. The crater wear is visualized by lighting the tool by a He-Ne gas laser system developed in this study. By means of this system it is research to evaluate classical parameters of tool wear and to have complete information about tool wear morphology.

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Analysis of multi-facet drill(MFD) performance and optimization of MFD geometry (다면 드릴의 성능 해석과 최적화)

  • 이상조;윤영식
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.6
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    • pp.1523-1532
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    • 1990
  • The objective of this study is to develope an optimized multi-facet drill (MFD). The principal factors that affect drilling performance are its geometry and the cutting conditions. In particular, the helix angle in the total twist angle of the twist drill, affects much morgen influence on the dynamic and static stiffness and on determining the characteristics of the chip disposal capacity of the drill. In this study, considering the helix angle as a major parameter, the model was developed. From this model, the deformation of transverse direction was simulated with the bending forces applied. The performance of a drill largely depends upon drilling forces. Comprehensive models for predicating the drilling thrust and torque are developed for the different drill geometries. The effects of MFD geometric parameters on thrust and torque are also deduced from the prediction models, from which an optimal drill geometry is found with the emphasis on minimum drilling forces.

The Export-import Trends of Agricultural Products in Malaysia (말레이시아 농산물 수출입 동향)

  • Kim, Choong-Soo;Lee, Sok-Young
    • Korean Journal of Agricultural Science
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    • v.33 no.2
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    • pp.97-106
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    • 2006
  • To strengthen the competitiveness of agricultural sector of the Korea, the direction of market trends on agriculture of the Malaysia was reviewed. The most dominating agricultural area in value is palm oil products, and forest products, sea products poultry products and rubber products is in order. The cultivated area of highest two top plants, oil palm and rubber, was about 4.4 million hectares in 2005, but it is decreasing year by year. Comparatively, rice field, pine apple and fruits tree cultivating area is increasing in tendency by the year. Among all the agricultural products, those items such as pork meat, poultry, egg were self-sufficient, rice, fruits, vegetables and sea products were about 70 to 80% self-sufficient, and beef meat, goat meat and milk were below 20% self-sufficient. Most of the grains, such as wheat, rice, barley, corn etc. and their processed food were imported. Also, temperate fruits such as apple, pear, and water cultivated as well as sprouting vegetables are imported. Ornamental products as cutting flowers and orchids are exported to mainly to the Singapore, but high quality temperate fruits and vegetables are imported from Australia. Oil palm exportation covers the balance of the other items imported and obtaining the foreign money as well in Malaysia.

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Indirect Method for Measurement of Tool Edge Roughness in flat End Mill (평 엔드밀 공구인선부 조도의 간접적인 측정법)

  • Kim, Jeon-Ha;Gang, Myeong-Chang;Kim, Jeong-Seok
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.10
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    • pp.92-98
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    • 2002
  • End mill is an essential tool to generate complex surface in workpiece and it has been developed with various materials and tool shapes. The most important factor to evaluate the performance of end mill is still the wear characteristics of flank face. In addition to the flank wear, the tool edge roughness generated by the chipping is another important factor in aspects of material property and machinability evaluation and affects the quality of machined surface. Up to now, there is no direct method for measurement of tool edge roughness. In this study, the tool edge roughness of flat end mill is indirectly measured along the axial direction of workpiece. The theoretical equation is derived in consideration of tool geometry. Finally, the optimal conditions to measure the tool edge roughness by the proposed method are presented through the theoretical review and experimental identification.

A Study Suggesting the Development Direction of the Next Generation Digital Library (차세대디지털도서관의 발전방향논의에 관한 연구)

  • Noh, Younghee
    • Journal of the Korean Society for information Management
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    • v.31 no.2
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    • pp.7-40
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    • 2014
  • This study proposes to identify digital library services applying cutting-edge technologies, and attempt to investigate the applicability of these technologies and services to domestic libraries. To this end, we reviewed main research which discusses next generation digital libraries, and examined thoroughly main technologies which can be applied to future libraries. As a result, the core technologies, concepts, and tools of the next generation of digital library are: cloud services, space for infinite creating (makerspace), big data, augmented reality, context-aware technologies, Google-glass, a revolutionary display technology, open linked-content-offering method, and so on. Specific cases of libraries already utilizing these technologies are also discussed.

Characteristics of Upcycle Designs in Product and Fashion Design (업사이클 제품 및 패션 디자인의 제작기법과 특성)

  • Lee, Lumi;Yim, Eunhyuk
    • Journal of Fashion Business
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    • v.19 no.4
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    • pp.1-20
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    • 2015
  • Acceleration of the fashion cycle has caused problems of environmental pollution because consumers made a lot of waste of clothes. To solve them, upcycle design has been uprised. This study researched the present condition through recent cases of upcycle design. The standard of collected cases is focused on used products which was already run out once and then has been recreated by being recreated with new design. Through this study, there is a purpose to provide solution of environmental pollutions and a right direction of upcycle fashion design. Collected cases are classified into five production methods. First method is Melting and Compressing, which it melts or compresses materials. Second method is Gathering and Combining, which it gathers or combines each different materials. Third method is Cutting and Dividing, which it cuts or divides products materials. Fourth method is Mixing and Changing, which it mixes materials, adds design elements, and changes of purpose. Final things are classified with multiplicatively used factors which are already divided.