• 한국통신학회논문지
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• 제21권10호
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• pp.2687-2702
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• 1996

It is desirable that the implementation of next generation information infrastructure is the Integrated Network combining the satellite and the terrestrial network. The application of the ATM network being the dominant infrastrure of terrestrial network to the satellite network is being studied variously. Considering these concepts, this paper analyzes due to ATM transport via satellite, evaluates the degradation of QoS and proposes reliable method of ATM cell transport via satellite. Because ATM is investigated with the optical fiber which is almost error free characteristics, the practical application of ATM transport via satellite essentially need the channel coding(FEC:Forward Error Correction) to enhance BER performance. But using the FEC coding, satellite link has burst error characteristics which evoke severe performance degradation fo ATM QoS. Therefore in satellite link, we analyze burst error characteristics using experimental results of computer simulation. Then to compensate these characteristics, based on this analysis and HEC dual mode algorithm we propose various interleaver structures(Block interleaver, Intra interlever, and Inter-Intra interleaver) to improve cell transmission QoS. We execute performance evaluations of iterleaver structures by computer simulation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.577-595
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• 2017

${\bullet}$ Silicon Carbide (SiC) had excellent material properties as the base material for next generation of power semiconductor. In developing SiC MOSFET, gate oxide reliability issues had to be first overcome before commercial application. Besides, a high and stable gate-source voltage threshold $V_{GS(th)}$ is also an important parameter for operation robustness. SiC MOSFET with such characteristics can directly use existing high-speed IGBT gate driver IC's. ${\bullet}$ The linear voltage drop characteristics of SiC MOSFET will bring lower conduction loss averaged over full AC cycle compared to similarly rate IGBT. Lower switching loss enable higher switching frequency. Using package with auxiliary source terminal for gate driving will further reduce switching losses. Dynamic characteristics can fully controlled by simple gate resistors. ${\bullet}$ The low switching losses characteristics of SiC MOSFET can substantially reduce power losses in high switching frequency operation. Significant power loss reduction is also possible even at low switching frequency and low switching speed. in T-type 3-level topology, SiC MOSFET solution enable three times higher switching freqeuncy at same efficiency.

• 한국전기전자재료학회논문지
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• 제24권6호
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• pp.449-457
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• 2011

Effect of pump combinations on the vacuum characteristics of vacuum system was simulated for optimum design of system. In this investigation, the feasibility of modelling mechanism for VacSimMulti simulator was proposed. Simulation results of various pumping combinations showed the possibilities and reliabilities of simulation for the performance of vacuum system in specific semiconductor processing. Simulation of roughing pump presented the expected pumping behaviors based on commercial specifications of employed pumps. Application of booster pump exhibited the high pumping efficiency for middle vacuum range. Combinations of optimum backing pump for diffusion and turbo vacuum system were obtained. And, the predictable characteristics of process application of both simulated systems were also acquired.

• 대한생식의학회:학술대회논문집
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• 대한생식의학회 2007년도 제52차 춘계학술대회 초록집
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• pp.15-16
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• 2007

• 농촌계획
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• 제23권4호
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• pp.153-168
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• 2017

The main objective of this study was to assess reference evapotranspiration based on multiple GCMs (General Circulation Models) and estimation methods. In this study, 10 GCMs based on the RCP (Representative Concentration Pathway) 4.5 scenario were used to estimate reference evapotranspiration. 54 ASOS (Automated Synoptic Observing System) data were constructed by statistical downscaling techniques. The meteorological variables of precipitation, maximum temperature and minimum temperature, relative humidity, wind speed, and solar radiation were produced using GCMs. For the past and future periods, we estimated reference evapotranspiration by GCMs and analyzed the statistical characteristics and analyzed its uncertainty. Five methods (BC: Blaney-Criddle, HS: Hargreaves-Samani, MK: Makkink, MS: Matt-Shuttleworth, and PM: Penman-Monteith) were selected to analyze the uncertainty by reference evapotranspiration estimation methods. We compared the uncertainty of reference evapotranspiration method by the variable expansion and analyzed which variables greatly influence reference evapotranspiration estimation. The posterior probabilities of five methods were estimated as BC: 0.1792, HS: 0.1775, MK: 0.2361, MS: 0.2054, and PM: 0.2018. The posterior probability indicated how well reference evapotranspiration estimated with 10 GCMs for five methods reflected the estimated reference evapotranspiration using the observed data. Through this study, we analyzed the overall characteristics of reference evapotranspiration according to GCMs and reference evapotranspiration estimation methods The results of this study might be used as a basic data for preparing the standard method of reference evapotranspiration to derive the water management method under climate change.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.225-225
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• 2017

This study is to investigate the effect of split application and adapted fertilization application cultivation in stable medicinal herbs production of Acorus graminens S. And it accomplished one's purpose to GAP guide manual established standard method of cultivation technology, contribute to the enlargement of farm's income. Method of fertilization application were conducted under five condition compose to standard application(N-P-K-Compost: fermented mixed oil cake fertilizer applied at $4-2-6-300kg.10a^{-1}$, twofold application(N-P-K-Compost applied at $8-4-12-600kg.10a^{-1}$) cultivation. Compost (fermented mixed oil cake fertilizer) and fused phosphate applied at 100% of basal fertilizer in April 14. The split application level of standard application and twofold application(N-K) applied at 100%, 50%, 40% of basal fertilizer in April 14, 50% and 40% of top dressing were three times application (N-K) in June 1, July 15, August 15, 25% and 20% respectively. Transplanting with Naju varieties in May 12 by growing pot seedling for 40 days in 2015. Planting density were spaced 30 cm apart in rows 30 cm apart with black vinyl mulching on open cultivation. Plot design randomized block 3 repetition. Therefore, growth characteristics by 50% and 40% of top dressing were three times application (N-K) compared to standard application and twofold application (N-K) applied at 100% basal fertilizer, aerial part as a result were so many such amount of growth as number of leaf per plant, etc., Length of diameter and main root of subterranean part growth increment rising highest. Dried roots yields treated standard fertilizer 100% application($250kg.10a^{-1}$) compared to 100% from twofold application (N-K) applied at 50% basal fertilizer, 50% and 40% of top dressing were three times application increased by 16%, 20%. respectively.

• 정보처리학회논문지A
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• 제13A권7호
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• pp.561-572
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• 2006

모바일 다비이스는 시스템 자원이 매우 제한적이기 때문에 응용프로그램을 실행시키기 위해서는 자원들을 효율적으로 관리하여야 한다. 특히 제한적인 메모리에 대한 동적 관리기법은 모바일 디바이스의 운영체제 및 플랫폼에서 매우 중요한 요소이다. 그러나 기존 동적 메모리 관리기법들은 응용프로그램의 실행 스타일과 사용되는 객체의 라이프 타임(life time), 객체 종류 및 종류 분포를 고려하치 않음으로써 효율적으로 메모리를 관리할 수 없으며, 응용프로그램의 실행 속도를 저하시킨다. 따라서 본 논문에서는 모바일 응용프로그램의 실행 특성을 분석하고, 분석한 결과를 토대로 모바일 디바이스용 응용프로그램의 실행 시 메모리를 절약하고, 실행 속도를 향상시키는 새로운 동적 메모리관리기법을 제안 및 개발하였다. 기존 동적 메모리 관리 모듈과의 응용프로그램 실행 속도를 비교한 결과. 제안한 동적 메모리 관리기법은 테스트용 응용프로그램을 실행할 때 링크드 리스트[11]에 비하여 6.5배, Doug. Lea 메모리 관리기법[13]에 비하여 2.5배, Brent 메모리 관리기법[15]에 비하여 10.5배 빠른 실행 속도를 보였다.

• 아시안잔디학회지
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• 제7권2_3호
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• pp.61-66
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• 1993

This experiment was carried out in order to study effect of organic fertilizer on the growth of Korean lawngrass(Zoysia matrella L. Merr.) and the change of soil chemical characteristics. Results obtained are summarized as follows: l. Organic fertilizer was appropriate for base-dressing in the establishment of turfgrass by means of sod. 2. Chlorophyll contents in mixed application plot of complex organic fertilizer were more abundant than that in single application plot of organic fertilizer. 3. The yield of dry weight in single application plot of organic fertilizer was greater about 40% than that in control plot. 4. As a whole, the growth of Korean lawngrass in mixed application plot of complex and organic fertilizer was more greater than that in single application plot of complex fertilizer. 5. Application of organic fertilizer promote effectiveness of available phosphorous in soil.

• Journal of Advanced Marine Engineering and Technology
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• 제26권4호
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• pp.425-431
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• 2002

In this study the characteristics of E-EGR valve developed by electrical method were analysed and the feasibility of application to vehicles was evaluated. The engine of smart car applied for diesel passenger car of small-displacement size developed by common vehicle was used for this experiment. It was installed a 3-cylinder, $0.8\ell$, turbo-charged light duty diesel engine with an electronic EGR valve. After the analysis and comparison of E-EGR valve performance by test bench, the estimation of vehicle application was executed through the EGR map and CVS-75 test result measured on the chassis dynamometer.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.943-947
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• 2005

This study was intended to interpose an objection about the analysis of rainfall spatial distribution without a proper standard, and offer the improved approach using 1,he geostatistical analysis method to analyze it. For this, spatially distributed daily rainfall data sets were collected for 41 weather stations in study area, and variogram and correlation analysis were conducted. In the results of correlation analysis, it was found that the longer distance between the stations reduces the correlation of the rainfall data, and maltes the characteristics of the rainfall spatial distribution. The variogram analysis shows that correlation range was less than 50 km for the 17 daily rainfall data sets of total 91 sets. It says that it involves some rike, to determine the application method for rainfall spatial distribution without some qualifications, hence the Application standards of the Rainfall Spatial Distribution Analysis Technique, were essential and that was contingent on characteristics of rainfall and landscape.