• 한국산학기술학회논문지
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• 제13권3호
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• pp.961-966
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• 2012

고유가 시대를 맞아 에너지 절약이 사회적으로 이슈화됨에 따라 진공유리에 대한 관심이 높아지고 있다. 진공유리 개발을 위한 핵심 공정 중 유리모서리 접합공정은 두 장의 유리 사이를 진공으로 유지하기 위해 높은 신뢰도를 요한다. 본 논문에서는 유리 모서리 접합 시 기존 프릿을 이용하여 접합하는 방법과 달리 고밀도열원인 수소혼합가스를 이용하여 모서리를 접합하는 공정을 제시하였다. 또한 유리의 파손 및 변형방지를 위해 전기로내의 분위기 온도를 설정하고 균일도를 측정하였다. 기초시험을 통해 모서리접합 공정변수를 설정하고 공정변수에 따른 유리 모서리 접합부 면적과의 수학적관계식을 다중회귀분석으로 도출하였다.

• Journal of Pharmaceutical Investigation
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• 제32권2호
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• pp.87-93
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• 2002

This study is to enhance drug penetration via skin and investigate anti-inflammation effect following adoption of ultrasound. For this goal gel containing triamcinolone was prepared and the skin penetration rate and the change effects of blood plasma ingredients and serum enzyme were investigated. Using Franz type diffusion cell and the skin of hairless mouse, the permeation enhancing effect of ultrasound was tested. After the injury by direct trauma, the blood test was performed by measuring WBC, lymphocyte, and neutrophyl, and by analyzing CPK and LDH. The ultrasound transducer whose technical specification is geometric area(GA) $1.4\;cm^2$, effective radiation area(ERA) $0.8\;cm^2$, and beam non-uniformity ratio(BNR) 6.0 max was used. The influence of frequency having an effect on skin permeation rate was higher in the case of using 1MHz and continuous treatment. The temperature of receptor phase was not influenced in skin permeation by phonophoresis. Skin permeation increase attended by intensity of ultrasound, the permeation of triamcinolone was accelerated at $2.5\;w/cm^2\;than\;1.0\;w/cm^2$. Following muscle injury phonophoretic group the number of WBC, neutrophil and lympholyte were decreased significantly as compared with both control group and ultrasound group. The result of variation of serum CPK and LDH activity conformed to the phonophoretic effect as same pattern with the variation of WBC, neutrophil and lymphocyte.

• 정보통신설비학회논문지
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• 제4권2호
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• pp.29-36
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• 2005

All-optical fiber-type $2{\times}32$ splitters for an Ethernet PON (passive optical network) were fabricated by using a FBT (fiber biconical tapered) process and the performance of the splitters was tested in upstream transmission of the EPON system. The $2{\times}32$ splitters was obtained by cascading $1{\times}4$ splitters fabricated by a conventional FBT process and showed -18 dB of insertion loss with 1.5 dB uniformity of output power at each channel and -0.1 dB of polarization dependent loss. The insertion loss variation was below 0.1 dB at the temperature range of $-40^{\circ}C\;to\;80^{\circ}C$. For upstream channel transmission test in the EPON system were a Zig board and a burst mode receiver. Zenko-made optical module was used for the burst mode receiver by adding functions of serializer/deserializer and clock data recovery, a Virtex II pro20 chipset and Vitesse VSC7123 were used in the Zig board for characterizing the burst mode and in the clock data recovery chipset, respectively. Startup acquisition lock time and data acquisition lock time were measured to be 670ns and 400ns, respectively, in the upstream channel transmission of the EPON system adapting the $2{\times}32$ splitter fabricated in this work.

• 한국조경학회지
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• 제30권2호
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• pp.95-104
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• 2002

This study was carried out to investigate the effects of pyroligneous acid on turfgrass growth and to propose usage for sustainable management on Korean golf course green. Each plot was treated with 0, 300, 500, and 800 acid to water solution. On all the plots, turfgrass growth increment and visual quality were measured at fried times. The data were subjected to paired samples t-test and corelation analysis. The summarized results are as follows; 1) Leaf growth increment, density, and root spread depth of turfgrass treated with 1: 500 and 1: 800 diluted pyroligneous acid were significantly superior to the control. Particularly, 1: 500 diluted solution was superior to the others. 2) Color, texture, and uniformity of turfgrass treated with 1: 500 and 1: 800 diluted pyroligneous acid were significantly superior to the control. Especially, 1: 500 diluted solution tended to be superior to the others. 3) There were no symptoms of disease in all plots treated with the diluted pyroligneous acid. 1 500 and 1: 800 diluted pyroligneous acid were not thought to trigger or promote disease. 4) Before and after investigating the effect of pyroligneous acid on turfgrass growth ,the soils were analyzed. In all treatments, the chemical properties of the soils did not change noticeably. The chemical properties of the soils might be not changed by the diluted pyroligneous acid treatments. 5) Considering the results mentioned above, 1: 500 diluted pyroligneous acid was the most effective. Though pyroligneous acid is an organic fertilizer and contains only a little nitrogen and phosphorus, 1: 500 diluted pyroligneous acid promoted turfgrass growth effectively. Thus this use might lead to a reduction in the amount of fertilizers used and result in ecologically responsive management of Korean golf courses.

• KIEAE Journal
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• 제15권3호
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• pp.49-56
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• 2015

Purpose: Due to recent increase on energy consumption for light in building, many studies to mitigate this issue have been conducted. Various researches have been carried out to suggest light shelf as one of the solutions, but researches for its reflectivity is very few. In fact, existing research on light shelf shows that utilizing more than 90% of high-illumination materials causes imbalance of glare and illuminance. Method: Therefore this research aimed to evaluate the performance of light shelves depending on reflectivity and to identify proper solution through test-bed. Result: The results are following: 1) Increased reflectivity generally contributed to increase of indoor illuminance but degrade uniformity factor related with indoor comfort of light environment. 2) The $0^{\circ}fixed$ light shelf with 75% of reflectivity and width of 300mm and 40mm appeared to consume more energy than other shelves. Therefore, it is analyzed as unsuitable. 3) This research was conducted by calculating appropriate angle of light shelf around winter and summer solstices and vernal/autumnal equinox. Based on this, performance evaluation was undertaken depending on reflectivity of movable light shelf, which is activated by external sources and can be applied with lower reflectivity than fixed shelf. However, one exception was a movable shelf with width of 600mm that increased light energy consumption when 75% of reflectivity was applied. 4) Performance evaluation of fixed and movable light shelf showed that the shelf with 80% of reflectivity came up with suitable results, but 75% of reflectivity may be applied depending on the width and angle of the shelf. This research is meaningful in that estimation of appropriate reflectivity of light shelf can resolve the glare problem and improve light environment, and further research would be desirable under more diverse conditions to identify proper solution.

• 응용통계연구
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• 제6권1호
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• pp.125-143
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• 1993

관측치가 (0, T]의 구간에서 균일하게 분포한다는 가설에 대하여, 관측치의 집락화를 검정하는 과정에서 스캔 통계량을 사용할 수 있다. 본 논문에서는 스캔 통계량의 확률분포의 근사분포가 어떠한 이론적 배경으로 개선되어 왔는 지를 고찰하고, 실제로 응용된 예를 살펴보기로 한다. 광물 매장을 조사하기 위한 항공탐사, 두 개의 아미노산 염기서열(amino-acid sequence)을 비교하는 과정에서 스캔 통계량은 사용되어 왔다. 지놈(genome)의 連鎖(sequence)에서 돌연변이가 발생한 위치에 대하여 집락의 가능성을 검색하는 방법으로 스캔 통계량을 이용할 수 있음을 보이고, 이에 대한 구체적인 문제 구성은 추후 연구과제로 제시한다.

• Nuclear Engineering and Technology
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• 제2권3호
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• pp.149-161
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• 1970

국내에서 산출되는 광물골재를 사용하여 방사선 차폐용 중차폐 콘크리트를 제조하고 감마선에 대한 차폐효능을 규명하는 동시에 방사선 차폐체로서의 활용가능성을 검토하였다. 10여종의 각기 다른 광물골재를 수집하여 방사선 차폐용 골재로서의 사용타당성을 검토하기 위한 물리시험과 화학분석이 실시되었고 이 결과를 토대로 최적한 골재를 선택하여 중차폐 콘크리트가 제조되었다. 차폐용 콘크리트를 제조하는데 골재의 배합비, 물-세멘트 비율, 세골재, 조골재 비율 등을 달리해주므로써 방사선 차폐효과가 달라지는 현상을 실험적으로 구해 보았고 그 결과 차폐체의 비중이 높고 균질성이 좋은 중차폐체의 설계 조건을 유도해 낼수 있었다. 각기 다른 중차폐체에 대한 차폐효능 실험은 60Co 감마선원을 사용한 방사선 투과시험법으로 구했다. 실험을 통하여 중차폐체에 대한 방사선 차폐능과 차폐콘크리트의 비중, 차폐가격등을 분석하므로써 차폐설계상 최적의 공간배치로서 가장 경제적으로 차폐치를 설계할 수 있는 최적의 조건을 얻을 수 있었다.

• 한국진공학회지
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• 제11권4호
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• pp.194-200
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• 2002

MOCVD(metal-organic chemical vapor deposition) Cu 박막을 여러 조건에서 열처리를 행하여 그 전기적 특성과 미세구조의 변화를 통해 적절한 열처리 조건을 찾고 그 효과를 조사하였다. Ar 1 torr, $400^{\circ}C$에서 열처리를 거친 Cu 박막의 비저항이 1.98 $\mu$Ω.cm로 가장 낮게 나타났으며, 결정성의 경우도 $I_{(111)}/I_{(200)}$의 비가 2.03에서 3.11로 열 처리를 거치지 않았을 경우와 비교해서 약 50% 정도 향상된 값을 나타내었다. 열처리 후의electromigration(EM) 테스트에서는 Ar 1 torr, $400^{\circ}C$에서 열처리를 거친 배선이 EM에 대한 가장 높은 저항성을 보였다. 이것은 열처리 후 낮은 비저항, (111) 결정면의 성장, 그리고 표면 거칠기의 감소에서 기인한 것이다.

• 한국광학회지
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• 제23권2호
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• pp.55-63
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• 2012

본 논문에서는 광생물 반응기의 조명 시스템으로 활용될 LED(Light-Emitting Diode)용 도광판의 광학설계 및 제작 결과에 대해 보고한다. 도광판 설계를 위해 광원, 반사필름, 도광판 패턴에 대한 모델링을 수행하였다. 특히, 도광판 패턴의 경우 램버시안 산란체(Lambertian Scatterer)로 모델링을 수행하였는데, 테스트용으로 제작된 도광판의 조도분포와 부합하는 모델 파라미터(반사율, 산란체의 폭)를 매칭 시뮬레이션을 통하여 추출하였다. 추출된 모델 파라미터를 사용하여 광학설계를 수행하였으며, CNC(Computer Numerical Control) 가공을 통해 도광판을 제작하였고, 평균조도와 조도균일도 등의 광학 특성을 측정하였다.

• Steel and Composite Structures
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• 제6권2호
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• pp.159-182
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• 2006

Current fire design codes for determining the temperature within the structural elements that form part of a complete building are based on isolated member tests subjected to the standard fire. However, the standard time-temperature response bears little relation to real fires and doesn't include the effects of differing ventilation conditions or the influence of the thermal properties of compartment linings. The degree to which temperature uniformity is present in real compartments is not addressed and direct flame impingement may also have an influence, which is not considered. It is clear that the complex thermal environmental that occurs within a real building subject to a natural fire can only be addressed using realistic full-scale tests. To study global structural and thermal behaviour, a research project was conducted on the eight storey steel frame building at the Building Research Establishment's Cardington laboratory. The fire compartment was 11 m long by 7 m wide. A fire load of $40kg/m^2$ was applied together with 100% of the permanent actions and variable permanent actions and 56% of live actions. This paper summarises the experimental programme and presents the time-temperature development in the fire compartment and in the main supporting structural elements. Comparisons are also made between the test results and the temperatures predicted by the structural fire Eurocodes.