• 대한토목학회논문집
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• 제32권6D호
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• pp.557-563
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• 2012

본 연구에서는 광역경제권, 특히 대구광역권 내의 산업공간구조를 분석하기 위하여 국가교통DB센터에서 제공하는 화물O/D 자료를 이용하는 방법을 제시하고자 한다. 이를 위해 화물점유율(FOR), 화물의존도(FDR), 규모를 반영한 Scale parameter의 세 가지 지표를 이용하여 대구광역권의 공간구조 분석을 실시하였다. 그 결과, 화물의 이동패턴을 고려한 각 지표들로부터 지역간 산업구조 특성 및 산업공간구조를 알아보는 데 유의미한 결과가 도출되었다. 특히, 대구시의 경우 경산시, 구미시의 화물점유율(FOR)과 화물의존도(FDR) 비율이 매우 높은 지역 연관성을 가지는 것으로 나타났고 규모를 반영한 SP지표 결과에 따르면 대구시의 주요산업은 화학 및 금속공업이 주를 이루는 것으로 나타났다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 춘계학술발표회논문집(1)
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• pp.316-321
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• 1997

The mixing vane effect on the Critical Heat Flux (CHF) is discussed with focus on the vortex now effect. In the subchannel approach, this effect is not quantified by the calculation model, but directly taken into account by the CHF correlation itself through data analysis. The vortex now effect is identified the two Westinghouse correlations, and then the CHF margin issue given rise to by the Vantage-5H design change is evaluated and discussed. It is noted that deficiency about CHF dependency on the vortex flow effect could induce an error in the Departure from Nucleate Boiling Ratio (DNBR) sensitivity Calculation.

• 한국안전학회지
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• 제6권2호
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• pp.31-36
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• 1991

Quenching effects of acetylene and hydrogen into oxygen detonation by using detonation arrester ［DA］are studied in this paper. The experiments were carried out in cylinderical shock tube. 5m long, 30mm dia., with stolchlometric ratio ［SR］of each gas and 10-l20$\mu$ Cell Size of brass and Stainless Steel of DAs were installed in it To clarify arresting ability correlation with initial pressure, Pi, critical thickness, Tct, and shapes of supporting panel of DA are also investigated It is found that ­detonation velocities has most dependency on Pi, it shows notable changes around 0.5kgf/$\textrm{cm}^2$ for hydrogen, 0.15kgf/$\textrm{cm}^2$ for acetylen respectively, ­DA can be safety device able to arrest shock wave of detonation, ­over Tct flame transmission might be only the factor has to be considered, ­acetylene seems to be much more stronger detonation characteristics than hydrogen because of reaction heat.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2001년도 춘계 학술대회논문집
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• pp.149-154
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• 2001

Parallel performance of a Myrinet based PC-cluster was tested and compared with a conventional Fast-Ethernet system. A preconditioned Navier-Stokes code was parallelized with domain decomposition technique, and used for the parallel performance test. Speed-up ratio was examined as a major performance parameter depending on the number of processor and the network topology. As was expected, Myrinet system shows a superior parallel performance to the Fast-Ethernet system even with a single network adpater for a dual processor SMP machine. A test for the dependency on problem size also shows that network communication speed is a crucial factor for parallelized computational fluid dynamics analysis and the Myrinet system is a plausible candidate for high performance parallel computing system.

• Nutrition Research and Practice
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• 제7권2호
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• pp.122-131
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• 2013

Based on data generated from 180 randomly selected households with children age under five years old in Aysaita district of Afar region of Ethiopia, this study explored prevalence of malnutrition and scrutinized household characteristics, maternal characteristics, specifics of the child and economic variables associated with child malnutrition. The height-for-age Z-scores (HAZ), weight-for-height Z-scores (WHZ) and weight-for-age Z-scores (WAZ) were used to measure the extent of stunting, wasting and underweight, respectively. The results revealed that prevalence of long term nutritional imbalance and malnutrition status indicator (i.e. stunting) was 67.8%. The short term measure (wasting) was found to be 12.8% and underweight was found to be 46.1%. Moreover, children in households which are headed by women, and characterized by more dependency ratio, less access to assets, health services and institutions are more likely to be undernourished.

• Journal of information and communication convergence engineering
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• 제10권1호
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• pp.45-52
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• 2012

Thedenoising of a natural image corrupted by Gaussian noise is a long established problem in signal or image processing. Today the research is focus on the wavelet domain, especially using the wavelet threshold method. In this paper, a waveletbased image denoising modified adaptive thresholding method is proposed. The proposed method computes thethreshold adaptively based on the scale level and adaptively estimates wavelet coefficients by using a modified thresholding function that considers the dependency between the parent coefficient and child coefficient and the soft thresholding function at different scales. Experimental results show that the proposed method provides high peak signal-to-noise ratio results and preserves the detailed information of the original image well, resulting in a superior quality image.

• 한국통신학회논문지
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• 제27권3C호
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• pp.226-233
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• 2002

This paper proposes the web robot based on Multi-Agent which the mutual dependency should be minimized each other with dividing the function each to collect Webpage. In result it is written to make a foundation for producing the effective statistics to analyze the domestic webpages and text, multimedia file composition ratio through performance analysis of the implemented system. It is easy that Web robot of the sequential processing method to collect Webpage on the same resource environment produces the limit of collecting performance. So to speak Webpages have "Dead-links" URL which is produced by the temporary host down and instability of network resource. If there are much "Dead-links" URL in the webpages, it takes a lot of time for web robot to collect HTML. The propose of this paper to be proposed, makes the maximum improvement to extract the webpages to process "Dead-links" URL on the Inactive URL scanner Agent.

• 한국세라믹학회지
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• 제28권7호
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• pp.517-524
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• 1991

The CVD process of BPSG (BoroPhosphoSilicate Glass) and its thin film properties were studied. B2H6, PH3, SiH4 and O2 gases were reacted in a AP (Atmospheric Pressure) CVD system in the temperature range of 300℃ and 460℃. The interaction of B2H6 and PH3 was studied from the deposition rate and dopant incorporation change point of view. The dependency of BPSG step coverage on the temperature was changed with different O2/(B2H6+PH3+SiH4) ratio. Finally, the boundary which distinguishes the stable BPSG's from the ones that react with Di (Deionized) water or cleaning chemicals such as H2SO4, HCl, H2O2, NH4OH etc could be defined.

• The Korean Journal of Ceramics
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• 제4권3호
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• pp.222-226
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• 1998

$Cu_3N$ film deposited on silicon oxide substrate by r.f. reactive sputtering technique. Synthesis and properties of copper nitride film were investigated for its possible application to Cu metallization as adhesive interlayer between copper and $SiO_2. Cu_3N$ film was synthesized at the substrate temperature ranging from $100^{\circ}C$ to $200^{\circ}C$ and at nitrogen gas ratio above $X_{N2}=0.4. Cu_3N, CuN_x$, and FGM-structured $Cu/CuN_x$ films prepared in this work passed Scotch-tape test and showed improved adhesion property to silicon oxide substrate compared with Cu film. Electrical resistivity of copper nitride film had a dependency on its lattice constant and was ranged from 10-7 to 10-1 $\Omega$cm. Copper nitride film was, however, unstable when it was annealed at the temperature above $400^{\circ}C$.

• Computers and Concrete
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• 제1권2호
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• pp.189-209
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• 2004

Several extensions to the Thelandersson phenomenological model for concrete under transient high temperatures are explored. These include novel expressions for the temperature degradation of the elastic modulus and the temperature dependency of the coefficient of the free thermal strain. Furthermore, a coefficient of thermo mechanical strain is proposed as a bi-linear function of temperature. Good qualitative agreement with various test results taken from the literature is demonstrated. Further extensions include the effects of plastic straining and temperature dependent Poisson's ratio. The models performance is illustrated on several simple benchmark problems under uniaxial and biaxial stress states.