• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.9-14
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• 2005

The purpose of this study is to predict VOCs emission rates from multi-layers materials, which are composed of single-layer materials having various VOCs emission rates, by using effective diffusion coefficients of the single-layer materials. The study was consisted of two parts; the one is the prediction of VOCs emission rates from multi-layer materials through numerical methods. The other is the measurement of VOCs emissions rates of wall composite and floor composite in Mock-up rooms for comparing the prediction and the experiments' values. The results of the study show that the short-term VOCs emission rates of multi-layers materials can be predicted from the effective diffusion coefficients of single materials in odor accuracy.

• 한국재료학회지
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• 제12권3호
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• pp.190-194
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• 2002

InN/GaN multi-layers were grown by metalorganic chemical vapor deposition(MOCVD) in order to get the appropriate structure for an high power blue-green light emitting diode(LED), and effects of growth conditions (growth temperature, pressure, and $trimethylindium(TMIn)-NH_3-N_2\; flow\; rare)$ on the integrated photoluminescence (PL) intensity and PL peak energy in InN/GaN multi-layers were investigated. The optimized growth conditions with the highest integrated PL intensity for InN/GaN multi-layers were obtained: the growth temperature at $780^{\circ}C$, the growth pressure at 325 Torr, the TMIn flow rate with 150 $m\ell$/min, the $NH_3$flow rate with 3.2 ι/min, and $N_2$ flow rate with 2 ι/min.

• Transactions on Electrical and Electronic Materials
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• 제13권1호
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• pp.27-30
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• 2012

This paper proposes a micro gas sensor for measuring $H_2S$ gas. This is based on a $SnO_2$-CuO multi-layer thin film. The sensor has a silicon diaphragm, micro heater, and sensing layers. The micro heater is embedded in the sensing layer in order to increase the temperature to an operating temperature. The $SnO_2$-CuO multi layer film is prepared by the alternating deposition method and thermal oxidation which uses an electron beam evaporator and a thermal furnace. To determine the effect of the number of layers, five sets of films are prepared, each with different number of layers. The sensitivities are measured by applying $H_2S$ gas. It has a concentration of 1 ppm at an operating temperature of $270^{\circ}C$. At the same total thickness, the sensitivity of the sensor with multi sensing layers was improved, compared to the sensor with one sensing layer. The sensitivity of the sensor with five layers to 1 ppm of $H_2S$ gas is approximately 68%. This is approximately 12% more than that of a sensor with one-layer.

• 인터넷정보학회논문지
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• 제16권5호
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• pp.1-9
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• 2015

사이버 공간에서 첨예화, 복잡화되고 있는 공격을 일대일 방식으로 방어하는데 한계가 있으므로 보다 효과적인 방어 방법이 필요하다. 본 고에서는 내외부의 공격에 대해 자산을 체계적 적응적으로 방어할 수 있는 다중계층 보안체제 구축 방안을 제시한다. 방어지역(Defense Zone)을 중심으로 한 다중계층 보안체제의 구조를 고안하고, 사이버 위협분석과 방어기술 자동할당 등 구현에 필요한 기술요소들에 대해 논의한다. 또한, 다중계층 보안체제에 대한 효과와 적용성을 보인다. 향후, 제시된 방안의 구체화를 위해 방어지역에 대한 상세구조설계, 최적 방어기술 자동선택방법, 위협 탐지를 위한 정상상태 모델링 기술 등에 대한 연구가 필요하다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.159-160
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• 2002

To investigate the humidity effect on tribological behaviors of Si-DLC/DLC multi-layers, the samples were prepared using a system consisted of an ion-gun for deposition DLC films and a balanced magnetron sputter for introducing silicon atoms to Si-DLC films. The Si-DLC/DLC multi-layers were composed of pure DLC films and Si-incorporated DLC films alternatively and had different bilayer numbers. Hardness and residual stress were drastically decreased through the formation of Si-DLC/DLC multi-layers compared to those of the pure and Si-incorporated DLC films. Wear results obtained under the various humidity conditions (<10%, $40{\sim}50%$, and >85%) showed that the pure DLC film was largely depended on the humidity while the Si-DLC and the Si-DLC/DLC multi-layers were little affected by the environmental humidity. Although friction coefficients of all samples were increased with the relative humidity, the multi-layer films showed relatively lower friction coefficients that those of the single films.

• 반도체디스플레이기술학회지
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• 제16권2호
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• pp.27-31
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• 2017

AZO/Ag/AZO multi-layer films deposited on glass substrate by RF magnetron sputtering and thermal evaporator have a much better electrical properties than Al-doped ZnO thin films. The multi-layer structure consisted of three layers, AZO/Ag/AZO, the electrical and optical properties of AZO/Ag/AZO were changed mainly by thickness of Ag layers. The optimum thickness of Ag layers was determined to be $90{\AA}$ for high optical transmittance and good electrical conductivity. The Ag layers thickness $90{\AA}$ is an optical transmittance greater than 80% of visible light and the obtained multilayer thin film with the low resistivity of $8.05{\times}10-3{\Omega}cm$ and the low sheet resistance $5.331{\Omega}/sq$. Applying to TCO and Solar electrode will improve efficiency.

• Journal of the Optical Society of Korea
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• 제18권2호
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• pp.167-173
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• 2014

A novel multi-oxide layer structure for vertical cavity surface emitting laser (VCSEL) structures is proposed to achieve higher single mode output power. The structure has four oxide layers with different aperture sizes and thicknesses. The oxide layer thicknesses are optimized simultaneously to reach the highest single mode output power. A heuristic method is proposed for plotting the influence of these variable changes on the operation of optical output power. A comprehensive optical-electrical thermal-gain self-consistent VCSEL model is used to simulate the continuous-wave operation of the multi-layer oxide VCSELs. A comparison between optimized VCSELs with different structures is presented. The results show that by using multi-oxide layers with different thicknesses, higher single-mode optical output power could be achieved in comparison with multi-oxide layer structures with the same thicknesses.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.725-730
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• 2007

A framework of multi layered database is proposed for the integrated operation of civil infrastructure information in this study. The multi-layered database is a logically integrated database composed of standardized information layers. The framework of multi-layered database is defined by three axes, national assets, lifetime, and data levels. The axis of national assets indicates civil infrastructures such as bridges, dams, tunnels and power plants that can be considered as national key structures. The axes of lifetime and data levels indicate the standardized information layers generated from the life-phase of civil infrastructure and the priority of data in the information layers, respectively. The standardized information layers are basically composed of reusable data sets defined by information models. A prototype of standard database for steel bridges is constructed based on the framework as a proof of concept. Demonstration examples such as data consistency check and automatic generation of a FEA model show that the proposed concept can assure the sustainable interoperability of civil infrastructure information as well as design information of steel bridges.

• 한국멀티미디어학회논문지
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• 제24권1호
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• pp.1-12
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• 2021

In this paper, we present a new architecture for semantic segmentation. Semantic segmentation aims at a pixel-wise classification which is important to fully understand images. Previous semantic segmentation networks use features of multi-layers in the encoder to predict final results. However, they do not contain various receptive fields in the multi-layers features, which easily lead to inaccurate results for boundaries between different classes and small objects. To solve this problem, we propose a multi-path feature fusion module that allows for features of each layers to contain various receptive fields by use of a set of dilated convolutions with different dilatation rates. Various experiments demonstrate that our method outperforms previous methods in terms of mean intersection over unit (mIoU).

• 전자공학회논문지B
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• 제33B권8호
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• pp.50-59
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• 1996

In this paper, a new hierarchical motion estiamtion scheme using the wavelet transformed multi-resolution image layers is proposed. Compared with the full search motion estimation method, the existing hierarchical methods remarkably reduce the amount of the computation but their efficiencies are depreciated by the local minima problem. In order to solve the local minima problem, the multi-resolution image layers are composed using the wavelet transform and the number of layers participated in the motion estimation for a block is determined by considering of its low band energy and higher band energy on the first wavelet transformed layer. The ratio between higher band energy and low band energy of each block is evaluated and in the case of the blocks which include relatively large higher band energy, the motion estimation is carried out in the high resolution layer. Otherwise, all layers are used. The final motion vectors are obtained in the first wavelet transformed layer. So less bits for motion vectors are transmitted, and the decomposition of received image using inverse wavelet transform decreases the blocking effect.