• Journal of Radiation Protection and Research
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• 제8권1호
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• pp.33-37
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• 1983

물 또는 콘크리트반사체(反射體)의 두께 및 콘크리트반사체(反射體)와 핵물질용액계(核物質溶液系) 사이의 간격에 따라 변(變)하는 유효증배계수(有效增倍係數)로서의 반사효과(反射效果)를 중성자수송이론(中性子輸送理論)에 기초를 둔 각분할방법(角分割方法)의 전산코드 ANISN으로 계산하였다. 그 결과에 따르면 반사체(反射體)의 두께가 엷을 때, 유효증배계수(有效增倍係數)를 기준으로 한 물 반사체(反射體)의 반사효과(反射效果)는 콘크리트에서보다 크지만 그 두께가 커지면 반대현상도 생기는 것 같았다. 한편 핵물질용액계(核物質溶液系)와 콘크리트반사체(反射體)사이에 물이 채워져 있고 그 간격변화에 따라 산출한 유효증배계수치(有效增倍係數値)는 처음 급격하게 감소하다가 약 15cm를 지나면서부터 서서히 감소하는 것 같았다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.664-667
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• 2004

It may have to establish the definite standard for performance evaluation basis about cementitious waterproofing material in job site that applied the method of construction formed cement waterproof course on concrete surface In present paper shows the effective selection method of waterproof layer of optimum thickness for economic performance as evaluating of the need thickness on waterproof property of penetrating waterproofing material.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.826-830
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• 1994

Making Brinell indentations facing each other near the crack tip is very effective method in increasing fatigue life. In this paper, fatigue test was performed after indentation to investigate the effect of thickness of specimen. The results show that fatigue lives increased my making indentation and retardation cycle is inverse proportional to thickness of specimen.

• 비파괴검사학회지
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• 제20권4호
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• pp.296-304
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• 2000

콘크리트 구조물의 성능평가 방법의 하나로 최근 들어 레이더가 널리 쓰이고 있다. 콘크리트 구조물 적용에 대한 레이더법의 발전을 위해서는, 콘크리트의 전자기적 재료 특성과 레이더의 작동원리를 이해하고, 활용하는 체계적인 연구노력이 필요하다. 본 논문에서는 레이더법의 유효 측정범위 설정과 레이더를 이용한 콘크리트의 두께측정 방법을 제시하고, 레이더 측정을 통한 콘크리트의 유전상수 계산 방법을 제안한다. 실험에서는 900mm (길이) $\times$ 600mm (폭)에 두께 50mm, 100mm, 150mm, 200mm, 250mm의 콘크리트 시편 5개를 사용하였다.

• 한국환경복원기술학회지
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• 제8권6호
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• pp.34-44
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• 2005

The objective of this study is to analyze the thermal properties of various green roof type. The experimental districts, have different soil thickness, soil type, the existence of module and the different kinds of vegetation, had installed. A measurement was conducted in Seoul University to investigate the thermal impacts of rooftop greening. The measurement point of temperature were 30, located in soil surface, middle of the soil layer, under the module, hard surface and soffit surface of each experimental district. The experimental investigation lasted from 6th August to 29th August, a total of 24 days. The results showed that green roof can contribute thermal benefits by soil and vegetation and reduce building energy consumption by a role of insulation. It's also better to make soil thickness over 20cm and various vegetation that should be more effective. The district installed only soil also could be effective for reducing the temperature of roof surface. Therefore, the increase of soil thickness and various vegetation could reduce more temperature of roof surface and building energy consumption. Also, it's helpful to reduce temperature that plant coverage rate be raised.

• 한국전기전자재료학회논문지
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• 제11권10호
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• pp.903-910
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• 1998

Ti:LiNbO$_3$ optical waveguides have been fabricated by Ti-diffusion in wet oxygen atmosphere. The fabrication conditions of furnace temperature, diffusion time and bubbler temperature were 105$0^{\circ}C$, 8 hours and 9$0^{\circ}C$, respectively and Ti thickness was varied from 700$\AA$ to 1500$\AA$. In this paper, the nearfield patterns, mode sizes (hirizontal/vertical) and insertion loss of waveguides were discussed at wavelength 1550 nm ad function of Ti thickness. With the planar waveguide, the effective index change and diffusion depth were calculated at 632.8nm using the prism coupling method. From these results, the best Ti thickness in our conditions seems like to by 1200$\AA$~1300$\AA$.

• Structural Engineering and Mechanics
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• 제40권6호
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• pp.783-800
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• 2011

This paper addresses the finite strip formulations for the stability analysis of viscoelastic composite plates with variable thickness in the transverse direction, which are subjected to in-plane forces. While the finite strip method is fairly well-known in the buckling analysis, hitherto its direct application to the buckling of viscoelastic composite plates with variable thickness has not been investigated. The equations governing the stiffness and the geometry matrices of the composite plate are solved in the time domain using both the higher-order shear deformation theory and the method of effective moduli. These matrices are then assembled so that the global stiffness and geometry matrices of a moderately thick rectangular plate are formed which lead to an eigenvalue problem that is solved to determine the magnitude of critical buckling load for the viscoelastic plate. The accuracy of the proposed model is verified against the results which have been reported elsewhere whilst a comprehensive parametric study is presented to show the effects of viscoelasticity parameters, boundary conditions as well as combined bending and compression loads on the critical buckling load of thin and moderately thick viscoelastic composite plates.

• Nuclear Engineering and Technology
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• 제35권2호
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• pp.144-153
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• 2003

The object of this paper is the probabilistic failure analysis on the cladding performance of WPF(Whole Pin Furnace) test fuel pins under transient conditions, and analysis of the KALIMER fuel pin using the preceding analysis. The cumulative damage estimation and Weibull probability estimation of WPF test are performed. The probabilistic method was adapted for these analyses to determine the effective thickness thinning due to eutectic penetration depth. In the results, it is difficult to assume that a brittle layer depth made by eutectic reaction is all of the thickness reduction due to cladding thinning. About 93% cladding thinning of the eutectic penetration depth is favorable as an effective thickness of cladding. And the unreliability of the KALIMER driver fuel pin under the same WPF test condition is lower than that of the WPF pin because of the higher plenum-fuel volume ratio and lower cladding inner radius vs. thickness ratio. KALIMER fuel pin developed from conceptual design has a more stable transient performance for a failure mechanism due to fission gas buildup than the WPF pin.

• JSTS:Journal of Semiconductor Technology and Science
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• 제15권1호
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• pp.41-47
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• 2015

In this paper, the effective electron Schottky barrier height (${\Phi}_{Bn}$) of the Ni silicide/n-silicon (100) interface was studied in accordance with different thicknesses of the antimony (Sb) interlayer for high performance n-channel MOSFETs. The Sb interlayers, varying its thickness from 2 nm to 10 nm, were deposited by radio frequency (RF) sputtering on lightly doped n-type Si (100), followed by the in situ deposition of Ni/TiN (15/10 nm). It is found that the sample with a thicker Sb interlayer shows stronger ohmic characteristics than the control sample without the Sb interlayer. These results show that the effective ${\Phi}_{Bn}$ is considerably lowered by the influence of the Sb interlayer. However, the current level difference between Schottky diodes fabricated with Sb/Ni/TiN (8/15/10 nm) and Sb/Ni/TiN (10/15/10 nm) structures is almost same. Therefore, considering the process time and cost, it can be said that the optimal thickness of the Sb interlayer is 8 nm. The effective ${\Phi}_{Bn}$ of 0.076 eV was achieved for the Schottky diode with Sb/Ni/TiN (8/15/10 nm) structure. Therefore, this technology is suitable for high performance n-channel MOSFETs.

• 한국안전학회지
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• 제13권4호
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• pp.79-86
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• 1998

The effect of specimen thickness on fatigue crack growth behavior has been carried out by compact tension specimens of thickness of 3mm, 10mm and 25mm for maraging steel and Al 7075-T6. The closure points were determined during the test by means of a clip-gage situated at the notch mouth. Specimen thickness have no apparent influence on the fatigue crack growth rate of maraging steel, but the crack growth rate of 25mm thickness specimen for Al 7075-T6 is faster than that of 3 and 10mm specimens. The difference of crack growth rates can be successfully explained by considering the different stress state of plane strain and plain stress due to the variation of specimen thickness. Also the crack opening ratio of 25mm specimen is greater than those of 3 and 10mm specimens. When a side groove is introduced in a 10mm specimen, the crack growth rate is approximately similar to that of 25mm specimen. The effective thickness expression of $B_e=B_o-(B_o-B_N)^2B_o$ is the most appropriate to evaluate the crack growth rate of side-grooved specimen. Fatigue crack growth rates can be well described by $\Delta K_{eff}$ of the crack closure points in regardless of all thickness and side-grooved specimens.