• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 1993년도 봄 학술발표회논문집
• /
• pp.117-124
• /
• 1993

The Neumann Expansion method has been used for evaluating the response variability of three dimensional truss structure resulting from the spatial variability of material properties with the aid of the finite element method, and in conjunction with the direct Monte Carlo simulation methods. The spatial variabilites are modeled as three-dimensional stochastic field. Yamazaki 〔1〕 has extended the Neumann Expansion method to the plane-strain problem to obtain the response variability of 2 dimensional stochastic systems. This paper presents the extension of the Neumann Expansion method to 3 dimensional stochastic systems. The results by the NEM are compared with those by the deterministic finite element analysis and by the direct Monte Carlo simulation method

• Journal of applied mathematics & informatics
• /
• 제28권1_2호
• /
• pp.383-395
• /
• 2010

In the present paper, we construct the traveling wave solutions involving parameters of nonlinear evolution equations in the mathematical physics via the (3+1)- dimensional potential- YTSF equation, the (3+1)- dimensional generalized shallow water equation, the (3+1)- dimensional Kadomtsev- Petviashvili equation, the (3+1)- dimensional modified KdV-Zakharov- Kuznetsev equation and the (3+1)- dimensional Jimbo-Miwa equation by using a simple method which is called the ($\frac{G'}{G}$)- expansion method, where $G\;=\;G(\xi)$ satisfies a second order linear ordinary differential equation. When the parameters are taken special values, the solitary waves are derived from the travelling waves. The travelling wave solutions are expressed by hyperbolic, trigonometric and rational functions.

• 대한치과의사협회지
• /
• 제12권1호
• /
• pp.37-42
• /
• 1974

To ascertain if the ultrasonic cleaning technique caused any dimensional changes in heat and cold curing and fluid resin denture bases and in addition to evaluate the dimensional changes of the resin denture bases stored in water and air, the author measured the distance between the outsides of two pins embedded in methyl methacrylate test denture bases by mean of 12 inch vernier caliper, accurate to 0.02mm. The results were as follows; (1) Ultrasonic cleaning didn't cause any permanent dimensional changes, but only affected temporary dimensional expansion in 16 test denture bases. (2) Temporary expansion rate caused by 10 minutes' ultrasonic cleaning was 0.29% and at the maximal temperature of the cleaning solution it was 0.64%. (3) The half of the denture bases stored in water showed the dimensional expansion rate of 0.47% while the others stored in air showed the dimensional shrinkage rate of 0.15% after 4 months.

• 대한치과기공학회지
• /
• 제42권2호
• /
• pp.107-112
• /
• 2020

Purpose: This study compares how accurately the specimen produced by the machining method and the rapid prototyping method is produced and how much dimensional error occurs with the finished casting body, and presents the results as experimental comparative data. Methods: Specimens produced using a digital processing method were cast by a conventional dental casting process, and dimensional changes of the finished casting body were measured to compare shrinkage and expansion. Results: In the control group that did not artificially induce large swelling, the dimensional error was the smallest, and the shrinkage and expansion reactions cannot be elimainated in all processes. Conclusion: The shrinkage and expansion depend on the given conditions, so if there is a change in the traditional dental casting process, it is necessary to adjust all the parameters to obtain an accurate casting body.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1998년도 추계종합학술대회 논문집
• /
• pp.1243-1246
• /
• 1998

Three-dimensional(3-D) sound is a technique for generating or recreating sounds so they are perceived as emanating from locations in a three-dimensional space. Three dimensional sound has the potential of increasing the feeling of realism in music or movie soundtracks. Three-dimensional sound effects depend on psychoacoustic spectral and phase cues being presented in a reproduced signal. In this paper we propose an effective algorithm for the sound image expansion in television system using stereo image enhancement techniques. Compared to the other techniques of three-dimensional sound, the proposed algorithm use only two speakers to enhance the sound image expansion, while maintaining the original sound characteristics.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
• /
• pp.243.1-243.1
• /
• 2014

For two-dimensional grid electrodes immersed in plasmas, sheath expansion due to negative high-voltage pulse applied to the electrode generates high-energy pseudowave. The high-energy pseudowave can be used as ion beam for ion implantation. To estimate ion dose due to high-energy pseudowave, investigation on sheath expansion of grid electroes is necessary. To investigate sheath expansion, an analytic model was developed by Vlasov equation and applying the 1-D sheath expansion model to 2-D. Because of lack of generalized 2-D Child-Langmuir current, model cannot give solvable equation. Instead, for a given grid electrode geometry, the model found the relations between ion distribution functions, Child-Langmuir currents, and sheath expansions. With these relations and particle-in-cell (PIC) simulations, for given grid electrode geometry, computation time was greatly reduced for various conditions such as electrode voltages, plasma densities, and ion species. The model was examined by PIC simulations and experiments, and they well agreed.

• Advanced Composite Materials
• /
• 제18권2호
• /
• pp.95-103
• /
• 2009

Composites can be designed to have special properties, and even such properties that are difficult to find in nature. We propose a simple approach to realize negative expansion upon wetting, i.e., contraction upon wetting, using swelling materials. The key parameters in one-dimensional case are investigated, and the possible configurations for two and three-dimensional cases are presented. The feasibility is demonstrated through a simple test.

• Interaction and multiscale mechanics
• /
• 제3권3호
• /
• pp.213-234
• /
• 2010

A multiscale method is presented for analysis of thin slab structures in which the microstructures can not be reduced to two-dimensional plane stress models and thus three dimensional treatment of microstructures is necessary. This method is based on the classical asymptotic expansion multiscale approach but with consideration of the special geometric characteristics of the slab structures. This is achieved via a special form of multiscale asymptotic expansion of displacement field. The expanded three dimensional displacement field only exhibits in-plane periodicity and the thickness dimension is in the global scale. Consequently by employing the multiscale asymptotic expansion approach the global macroscopic structural problem and the local microscopic unit cell problem are rationally set up. It is noted that the unit cell is subjected to the in-plane periodic boundary conditions as well as the traction free conditions on the out of plane surfaces of the unit cell. The variational formulation and finite element implementation of the unit cell problem are discussed in details. Thereafter the in-plane material response is systematically characterized via homogenization analysis of the proposed special unit cell problem for different microstructures and the reasoning of the present method is justified. Moreover the present multiscale analysis procedure is illustrated through a plane stress beam example.

• 한국정보과학회논문지:시스템및이론
• /
• 제30권7_8호
• /
• pp.381-386
• /
• 2003

본 논문에서는 완전이진트리의 3차원 메쉬로의 임베딩 문제를 다룬다. 링크 충돌을 2까지 허용하면서 최적크기의 메쉬에 임베딩하는 방법은 [1]에서 다루고 있으며, [2]에서는 최적크기의 1.27배의 메쉬로 임베딩하는 방법을 보여주고 있다. 본 논문에서 제안하는 임베딩 방법은 순위차원 라우팅을 사용하며 링크 충돌이 없는 방법으로, 약 1.125배의 최적확장을 넘지 않는다. 이 임베딩 방법은 링크의 충돌 혹은, 임베딩의 확장을 최소화한다는 기준에서 볼 때 기존의 임베딩 방법에 비해 향상된 결과이다.

• 한국의류학회지
• /
• 제23권1호
• /
• pp.22-29
• /
• 1999

This paper descrived the changes of peel strength wrinkle recovery and dimensional stability after fusing 4 different wool face fabrics with 3 different fusible interlinings. The fusing condition was conducted by fusing press machine under 4kg.f/cm2 at 15$0^{\circ}C$. To determine the effect of the varous physical properties of the fused fabrics face fabrics and interlinings on the peel strength wrinkle recovery and dimensional stability(hygral expansion and relaxation shrinkage) of fused fabrics correlation among the KES values of fused fabrics face fabrics and interlinings to the peel strength rinkle recovery and dimensional stability of fused fabrics were expeerimentally analyzed,. As the results the peel strength was mainly influenced by the cover factor of face fabric and interlinings. After fusing wrinkle recovery and hygral expansion were decreased. The cover factor wrinkle recovery weight thickness shear rigidity and frictional properties of face fabric and the thickness of fused fabrics were not influence to the wrinkle recovery of fused fabrics. In addition the dimensional stabilities of fused fabrics were mainly influenced by the tensile and frictional properties of the wrinkle recovery of fused fabrics. In addition the dimensional stabilities of fused fabrics were mainly influenced by the tensile and frictional properties of the face fabrics.