• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.689-696
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• 2002

The behavior of two-level soil-reinforced segmental retaining wall was examined using the finite element analysis. A number of different case was analyzed by varying the reinforcement length and the offset distance between the upper and lower wall. The results indicate that the interaction between the upper and lower walls can be neglected the upper wall is located beyond the distance of the lower wall height. A so found is that for moderate offset distances, the interaction between the two walls generally is limited to the external stability of the wall. Implication of the findings are discussed

• 한국주거학회논문집
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• 제23권3호
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• pp.63-70
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• 2012

Nowadays, a 1-2 person household if increasing due to the aging population and the low birth rate. Thus, in August 2011, Seoul held the 'College Student's Idea Competition', which dealt with small but strong housing that has a very reasonable structure in spite of its small scale in order to improve the quality of small housing for a 1-2 person households. The study indicates the characteristic of this small housing in order to target competition entries from college students; 93- works have been processed. First, the properties of residents are investigated through the number of household members and the relations of the residents. To ensure various element techniques of the entries, the study analyzes data via a structured analysis. Along with structured element techniques according to each level, eight element techniques of the furniture level, housing unit level, main building, and district-level are derived. This study suggests various element techniques in response to the efficiency of area in households as well as housing unit levels. Plans of public spaces and community life housing are offered at the level of the main building and at the district-level. Through an analysis of competition, the critical point of small house planning in deliberation is not only about space and economic efficiency of physical unit, but the life of the residents.

• 대한토목학회논문집
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• 제5권2호
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• pp.83-90
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• 1985

본(本) 논문(論文)은 제체(堤體)의 중앙심벽형(中央心壁型) model을 제작(製作)해서 상류측(上流側) 각(各) 수위(水位)의 변화(變化)에 대한 침투유량(浸透流量)을 실험(實驗)을 통하여 구하고, 이 때의 침윤선형상(浸潤線形狀)과 Equipotential line에 대하여도 고찰(考察)한 것이다. 또한 실험(實驗)에서 얻은 자료(資料)를 FEM기법(技法)을 사용하여 구한 유선망(流線網)의 각요소별(各要素別) Flow-rate에 대한 유속(流速)과 침투유량(浸透流量)을 실험치(實驗値)와 근사리론공식(近似理論公式)에서 산출(算出)된 값과 비교검토(比較檢討)하였다. 침투수량(浸透水量)은 고수위시(高水位時)에서는 실험치(實驗値)보다 FEM 값이 적게 나타났으며, 저수위시(低水位時)에는 거의 비슷한 값이었다. 그리고, 유선망(流線網)이 형성(形成)된 각(各) 요소별(要素別) Flow-rate 는 X, Z 축(軸)은 수위변화(水位變化)가 있어 흐름에 따른 유속(流速)이 크나 Y 축(軸)의 유속(流速)은 무시할 수 있을 정도의 적은 값이었다.

• 복식
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• 제66권2호
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• pp.1-14
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• 2016

This study was intended to investigate the influences that consumer's price sensitivity, bundle discount type, and price level of the male cosmetics have on consumer attitude. The design of this research was comprised of $2{\times}2{\times}2$ mixed design studies. The first element was high price sensitivity vs. low sensitivity, the second element was the bundle discount type (mixed leader vs. mixed-joint), and the third element was the price level of male cosmetics (high-price brand vs. low-price brand). The results of this study showed that price sensitivity, bundle discount type and price level of male cosmetic had a statistically significant interaction effect on the consumer's quality perception. The quality perception of low-cost brands for high price sensitivity/mixed-joint bundle group was low. The quality perception of low-cost brands for mixed-leader bundled groups did not change significantly even when the price sensitivity became higher. However, it can be seen as the same result that the overall value is higher when suggested the price information in Mixed-leader bundle than Mixed-joint bundle. In particular, this study suggests that price information should be presented in mixed-leader bundles for high price sensitivity and low cast brands.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.565-567
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• 2008

In the present study, a least square/level set based two-phase flow code has been developed using finite element discretization, which can be utilized for the analysis of a free surface flow problem in a complex geometry. Since the finite element method is employed for the spatial discretization of governing equations, an unstructured mesh can be naturally adopted for the level set simulation of a bubble-in-liquid flow without an additional load for the code development except that solution methods of the hyperbolic type redistancing and advection equations of the level set function should be devised in order to give a bounded solution on the unstructured mesh. For the discretization of hyperbolic type redistancing and advection equations, least square method is adopted. From the numerical experiments of the present study, it is shown that the proposed method is both robust and accurate.

• 한국전기전자재료학회논문지
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• 제28권12호
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• pp.802-807
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• 2015

This paper describes the development of a piezoelectric level switch, which aims to effectively monitor the level status in high ambient temperatures. In order to adjust the impedance near the resonant frequency and temperature characteristics, the effect of the case and backing layer materials on its performance was analyzed using the finite element method (FEM). The suggested prototype new level switch has three heat-sink plates attached to SUS bar of 230 mm long, and case of PEEK which contains PZT sensing part. To illustrate the validity of this level switch, 10 samples are prepared and investigated the sensing performance through the high and low temperature ambient.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2401-2405
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• 2008

In the present study, a three-dimensional least square/level set based two-phase flow code was developed for the simulation of three-dimensional sloshing problems using finite element discretization. The present method can be utilized for the analysis of a free surface flow problem in a complex geometry due to the feature of FEM. Since the finite element method is employed for the spatial discretization of governing equations, an unstructured mesh can be naturally adopted for the level set simulation of a free surface flow without an additional load for the code development except that solution methods of the hyperbolic type redistancing and advection equations of the level set function should be devised in order to give a bounded solution on the unstructured mesh. From the numerical experiments of the present study, it is shown that the proposed method is both robust and accurate for the simulation of three-dimensional sloshing problems.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.259-262
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• 2005

The large transformers used in the electric power company become targets of public complaints because of those characteristics generating high-level noise. Reducing vibration level is the basis of noise control for the large transformers. For this reason, a vibrating reducing element is developed for the large transformers with a sub-element enduring seismic movement. Large attenuation of vibration is achieved by applying the element to the large transformers in a substation.

• Structural Engineering and Mechanics
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• 제91권4호
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• pp.357-368
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• 2024

In this study, a finite-element surface wave simulation using an effective elastic constant (EEC) was developed to calculate the Rayleigh wave velocity change and polarization change in aluminum, steel, and concrete under uniaxial stress. Under stress, an isotropic medium behaves like an anisotropic material during the wave propagation. The EEC is an equivalent anisotropic stiffness matrix which was derived to simulate the acoustoelastic effect using classical finite-element software. The vertical and horizontal surface displacements located 8-mm from a 1-㎲ excitation load were used to find the acoustoelastic coefficients k^v and k^p and compared to an analytical scheme. It was found that k^v for aluminum and concrete matched within 4% of the analytical solution. The finite-element simulation showed that the Rayleigh wave arrival time for concrete and aluminum was greatly influenced by the stress level. Thus, predicting the stress level using concrete and aluminum's acoustoelastic effect is applicable.

• The Journal of Korean Physical Therapy
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• 제22권6호
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• pp.77-83
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• 2010

Purpose: The aim of this study was to do numerical analysis of the wavelength dependence in low level laser therapy (LLLT) using a finite element method (FEM). Methods: Numerical analysis of heat transfer based on a Pennes' bioheat equation was performed to assess the wavelength dependence of effects of LLLT in a single layer and in multilayered tissue that consists of skin, fat and muscle. The three different wavelengths selected, 660 nm, 830 nm and 980 nm, were ones that are frequently used in clinic settings for the therapy of musculoskeletal disorders. Laser parameters were set to the power density of 35.7 W/$cm^2$, a spot diameter of 0.06 cm, and a laser exposure time of 50 seconds for all wavelengths. Results: Temperature changes in tissue based on a heat transfer equation using a finite element method were simulated and were dominantly dependent upon the absorption coefficient of each tissue layer. In the analysis of a single tissue layer, heat generation by fixed laser exposure at each wavelength had a similar pattern for increasing temperature in both skin and fat (980 nm > 660 nm > 830 nm), but in the muscle layer 660nm generated the most heat (660 nm ${\gg}$ 980 nm > 830 nm). The heat generation in multilayered tissue versus penetration depth was shown that the temperature of 660 nm wavelength was higher than those of 830 nm and 980 nm Conclusion: Numerical analysis of heat transfer versus penetration depth using a finite element method showed that the greatest amount of heat generation is seen in multilayered tissue at = 660 nm. Numerical analysis of heat transfer may help lend insight into thermal events occurring inside tissue layers during low level laser therapy.