• Title/Summary/Keyword: surface form

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A study on the design wax up technique for mandibular molar occlusion surface (하악구치 교합면의 design 조각법에 관한 연구)

  • Moon, Hee-Kyung
    • Journal of Technologic Dentistry
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    • v.24 no.1
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    • pp.107-126
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    • 2002
  • The first function of occlusion is mastication. Therefore the functional restoration of occlusal surface is very important. The restoration of occlusal surface is three method as wax bite technique, F.G.P. technique, cone technique. Many dental technician is using compound method. I am using compound method of wax bite technique and cone technique. I have knew common point on each teeth during I have waxing up wax pattern. So I studied on the design waxup technique for mandible molar occlusion. The results of the study were as follows; 1. The dam wax up method can restore axial contour of teeth very easy and make short working time of wax pattern. 2. The height of dam must be same with cusp of adjacent teeth. 3. Automatically the contour of tooth is appeared if the contour of dam is relationship with cuspid line of adjacent teeth. 4. The height of contour of buccal, lingual surface is formed natural curve to add fluid wax by gravitation. 5. The development groove of mandible first premolar is appeared V form. 6. The development groove of mandible second premolar is appeared Y form. 7, The development groove of mandible first molar is appeared M form. 8. The development groove of mandible second molar is W form. 9. The embrasure is formed to carve around contact point area as round convex. It affects to axial form of tooth. 10. The buccal, lingual groove of molar is formed parallel with direction of teeth arrangement.

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A Study on Dusting of Formed Concrete Surface (목제(木製)거푸집 사용으로 콘크리트표면(表面)에 발생(發生)하는 경화불량현상(硬化不良現象)에 대한 연구(研究))

  • Moon, Han Young;Choi, Jae Jin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.3 no.2
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    • pp.73-85
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    • 1983
  • We occasionally find a thin layer of imperfectly hardened concrete surface when the wood form is stripped off. It has been generally believed that the principal causes were the effects of reactive form oil, adhesive agent or formalin which has been used in the course of plywood manufacturing. However, in this experiment, it became clear that the concrete surface could be influenced more harmfully by a certain species of wood form and the storage conditions of wood form rather than any other causes. Especially, the main cause of the severely dusty layer is the use of wood form exposed to sun for a long period. Countermeasures, therefore, for preventing concrete surface from dusting are also discussed in this paper.

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A Study on the Preliminary Design of Hull Form considering Viscuous Resistance (점성저항을 고려한 선형의 초기설계에 관한 연구)

  • 이경도
    • Journal of Ocean Engineering and Technology
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    • v.14 no.2
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    • pp.112-116
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    • 2000
  • To determine a preliminary hull form with a minimum viscous resistance this study considers the systematic variations of full form and calculations of the viscous resistance for varied hull forms. A preliminary hull form can be determined from a parametric study of viscous resistance.

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Analysis of Interfacial Surface Crack Perpendicular to the Surface (표면에 수직한 계면방향 표면균열의 해석)

  • 최성렬
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.2
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    • pp.277-284
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    • 1993
  • Interfacial surface crack perpendicular to the surface, which is imbedded into bonded quarter planes under single anti-plane shear load is analyzed. The problem is formulated using Mellin transform, form which single Wiener-Hopf equation is derived. By solving the equation stress intensity factor is obtained in closed form. This solution can be used as a Green's function to generate the solutions of other problems with the same geometry but of different loading conditions.

High-temperature oxidation of Ti3(Al,Si)C2 nano-laminated compounds in air

  • Lee, Hwa-Shin;Lee, Dong-Bok
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2007.11a
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    • pp.147-148
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    • 2007
  • The compound, Ti3(Al,Si)C2, was synthesized by hot pressing a powder mixture of TiCX, Al and Si. Its oxidation at 900 and 1000 oC in air for up to 50 h resulted in the formation of rutile-TiO2, -Al2O3 and amorphous SiO2. During oxidation, Ti diffused outwards to form the outer TiO2 layer, and oxygen was transported inwards to form the inner mixed layer.

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Automatic Panelizing Algorithms of Free-form Buildings

  • Lee, Donghoon;Lim, Jeeyoung;Habimana, Gilbert;Lee, Taick-Oun;Kim, Sunkuk
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.425-428
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    • 2015
  • New technologies using a CNC machine are being developed to reduce the production cost of free-form buildings. For production of free-form members using such technologies, vast free-form buildings should be first split into multiple panels that are productible. Taking into consideration of the curved surface of free-form members, the segmented free-form panels may vary in shape and size, which may cause a lot of errors. In addition, it is time-consuming for the work. However, the current panelizing work is completed with the trials and errors of engineers and architectural designers even in large-scale projects, which results in increased construction duration and cost. Thus, it is necessary to develop a technology for panelizing free-form panels so as to maximize the economic feasibility of production technologies for free-form concrete members. The study intends to develeop automatic panelizing algorithms of free-form buildings considering the curved surface and size of free-form panels and the production conditions. The developed algorithms will be useful in applying the production technologies of free-form buildings using CNC machine and reducing the cost.

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A Study on the Determination of Setting Time of Concrete in the Determination of Slip-up Speed for Slip-Form System (슬립폼 시스템 상승속도 결정에 요구되는 콘크리트에서의 초기경화시간 결정을 위한 연구)

  • Kim, Heeseok;Kim, Young-Jin;Chin, Won-Jong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.4A
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    • pp.295-302
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    • 2011
  • The setting time which is the important element for the determination of slip-up speed of Slip-Form system is the hardening time of early-age concrete when the in place concrete has minimum compressive strength before the concrete appears out of Slip-Form system. But it is very difficult to predict the setting time because it depends on not only the composition ratio of concrete but also various conditions of construction fields. Thus, the technique to estimate accurately and continuously the hardening time of early-age in place concrete during operating Slip-Form system is necessary to guarantee the safety of Slip-Form system and the maintenance of the shape of concrete. Ultrasonic wave-based nondestructive testing methods have the advantages which are accurate and continuous in estimating concrete compressive strength. Of such methods, the method using surface wave which propagates along the surface of material is effective for thick member such as a pylon. Thus, in this paper a study on the determination of slip-up speed for Slip-Form system using surface wave velocity is performed. The relation between the slip-up speed of Slip-Form system and the setting time is formulated, and the surface wave velocity is estimated from continuous wavelet transform of the numerical results for surface wave propagation. Finally, the accuracy of this method according to the distance between the wave source and receivers and the relation between the estimated surface wave velocity and the elastic modulus are investigated.

Development of an Optimum Hull Form for a Container Ship with Minimum Wave Resistance (최소 조파저항을 가지는 컨테이너선의 선형최적화 기법에 대한 연구)

  • 최희종;서광철;김방은;전호환
    • Journal of the Society of Naval Architects of Korea
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    • v.40 no.4
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    • pp.8-15
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    • 2003
  • This paper presents the method for developing an optimum hull form with minimum wave resistance using SQP(sequential quadratic programming) as an optimization technique. The wave resistance is evaluated by a Rankine source panel method with non-linear free surface conditions and the ITTC 1957 friction line is used to predict the frictional resistance coefficient. The geometry of the hull surface is represented and modified using B-spline surface patches. The optimization method is applied to Series 60 hull and KCS(KRISO 3600 TEU Container Ship). The obtained results prove that the method is appropriate for preliminary hull form design.

An Integral-Augmented Nonlinear Optimal Variable Structure System for Uncertain MIMO Plants

  • Lee, Jung-Hoon
    • Journal of IKEEE
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    • v.11 no.1 s.20
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    • pp.1-14
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    • 2007
  • In this paper, a design of an integral augmented nonlinear optimal variable structure system(INOVSS) is presented for the prescribed output control of uncertain MIMO systems under persistent disturbances. This algorithm basically concerns removing the problems of the reaching phase and combining with the nonlinear optimal control theory. By means of an integral nonlinear sliding surface, the reaching phase is completely removed. The ideal sliding dynamics of the integral nonlinear sliding surface is obtained in the form of the nonlinear state equation and is designed by using the nonlinear optimal control theory, which means the design of the integral nonlinear sliding surface and equivalent control input. The homogeneous $2{\upsilon}(\kappa)$ form is defined in order to easily select the $2{\upsilon}$ or even $(\kappa)-form$ higher order nonlinear terms in the suggested sliding surface. The corresponding nonlinear control input is designed in order to generate the sliding mode on the predetermined transformed new surface by means of diagonalization method. As a result, the whole sliding output from a given initial state to origin is completely guaranteed against persistent disturbances. The prediction/predetermination of output is enable. Moreover, the better performance by the nonlinear sliding surface than that of the linear sliding surface can be obtained. Through an illustrative example, the usefulness of the algorithm is shown.

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Study on mirror-like surface machining of Al alloy with edge form of single crystal diamond tools (천연 다이아몬드 인선형태에 의한 Al 합금의 경면절삭에 관한 연구)

  • 김정두
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.6
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    • pp.1515-1522
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    • 1990
  • Ultra precision cutting should be satisfied with two conditions of Mirror Like and shape grade, and especially Mirror Like depends on surface roughness. In this study, in order to develop Mirror Cutting for Al alloy, this was done with edge form of single crystal diamond tool divided into R type and S type. Surface roughness machined by S type tool is more satisfactory than by R type tool, being the lowest value of 13.8nm. In addition, Mirror surface can reach above 90% of reflection rate by both R type and S type tool, but machined surface by R type tool has much more fine fracture portions rather than by S type tool. Even though feed rate decreases from 5.mu.m to 1.mu.m, surface roughness doesn't show improvement.