• 한국수자원학회논문집
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• 제31권3호
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• pp.243-252
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• 1998

본 연구에서는 새로운 무차원값을 제시하여 도시유출모형의 매개변수결정을 위한 상대적인 민감도분석을 실시하여 매개변수별 민감도특성을 구명하였다. 민감도분석을 위한 무차원값으로 총유출량비,첨두유출량비, 유출민감도비, 민감도비율을 다음과 같이 개발하였다. $$ 유역면적의 크기와 강우분포형과 강우지속기간별로 각 적용단계별 총유출량비, 첨두유출량비, 유출민감도를 산정하기 위해 ILLUDAS모형과 SWMM모형의 매개변수를 선저하고 적정 적용범위를 결정하였다.

• Journal of Pharmaceutical Investigation
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• 제40권3호
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• pp.193-200
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• 2010

The objective of this study was to investigate the effects of sample preparation, HPLC conditions and peak measurement methods upon determining progesterone content of poly-d,l-lactide-co-glycolide microspheres. A series of the microspheres with different formulations was first prepared. To determine their actual drug contents, the microspheres were dissolved in tetrahydrofuran and diluted with various amounts of methanol to precipitate the polymer. After removal of polymeric precipitates, the filtrates were subject to HPLC analysis under versatile experimental conditions. Interestingly, the composition of a sample solution (e.g., the ratio of methanol to tetrahydrofuran) affected the magnitudes of both peak fronting and peak broadening of progesterone. Its peak became broader and more asymmetrical at lower methanol:tetrahydrofuran ratios. Furthermore, its peak height was influenced by the proportion of tetrahydrofuran in a sample solution. Such problems encountered with tetrahydrofuran were exacerbated when a larger volume of the sample solution was injected onto an analytical column. Under our experimental conditions a peak area measurement provided more accurate and reliable determination of progesterone content in various microspheres than a peak height determination. Optimizing the composition of a sample solution, HPLC chromatographic conditions and peak analysis methods was a prerequisite to an accurate determination of progesterone encapsulated within microspheres.

• 한국수소및신에너지학회논문집
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• 제29권1호
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• pp.25-31
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• 2018

To apply Sievert's type apparatus to thermal analysis of hydrogen absorption materials, the dehydrogenation of $LaNi_5$ system was investigated. As the initial wt% of hydrogen was increased from 0.44 to 1.24 wt%, the peak temperature of evolution rate shifted to higher temperature. However, with the initial wt% of hydrogen higher than 0.95 wt%, the peak temperature of evolution rate did not change. As the heating rate was increased, the peak temperature increased; the peak temperatures for heating rates 0.5, 1.0 and 1.5 K/min were 262.2, 264.1, and 265.9 K respectively. The Sievert's type automatic apparatus can be successively applied to the thermal analysis of $LaNi_5$ hydride.

• 한국식품과학회지
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• 제28권6호
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• pp.1171-1176
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• 1996

레토르트 살균처리시 일어나는 계육 모형식품의 휘발성분 변화를 GC 및 GC-MS로 분석한 후 그 데이터를 활용하여 통계분석을 행하였다. 먼저, 분산분석으로 통계적으로 유의한 42개 peak를 선택하였으며 이를 독립변수로 하여 다변량 통계분석을 실시하였다. 단계적 판별분석법으로 두 시료집단의 차이를 명확히 구분하는 GC peak로서 2-heptanone 등 8개 peak를 순차적으로 얻었다. 이어서 선택된 8개 peak를 독립변수로 주성분 분석을 한 결과, 3개 주성분으로, 96.1%의 높은 판별이 가능함을 알 수 있었으며, 특히 PC1은 76.5%의 판별이 가능한 것으로 나타났다. 또한, 주성분을 이용한 요인분석(Factor Analysis)을 행하여 8개 peak 상호간의 관계를 검토한 결과 11, 20, 21번 peak는 그 방향성 및 크기가 거의 같았으며, 11, 20, 21번 peak 그룹과 9, 32, 39번 peak 그룹은 방향성이 서로 반대이며 크기도 매우 큰 것으로 밝혀졌다.

• 수산경영론집
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• 제37권1호
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• pp.1-24
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• 2006

Reducing fishing capacity is one of current issues in the international fisheries. This is because that increased fishing capacity has caused not only fish stocks to be depleted, but also additional fishing costs to be incurred, which resulted in reduction of economically viability of fisheries. For this reason, FAO adopted the International Plan of Action for the Management of Fishing Capacity' in 1999 and recommended member countries to estimate fishing capacity and to implement the policy to reduce fishing capacity. This study is aimed to measure fishing capacity of the Large Purse Seines Fishery that is one of offshore fisheries in Korea using both Peak - to - Peak Analysis and Data Envelopment Analysis in order to provide a policy information for preparation of domestic plan of action for the management of fishing capacity. The results of PTP Analysis were almost similar to those of DEA Analysis. The DEA results showed that the capacity utilization in 2004 was about 75%, it was obvious the capacity did not utilize enough. The sensitivity analysis on DEA results indicated that 24% of the number of ships, 26% of the tonnages, or 29% of the horse powers should be reduced if the present catch remained. In addition, if the catch remains at the MSY base level of large purse seines, the analysis suggested that the number of ships, tonnages and horse powers should be reduced by 15%, 18%, and 21% respectively.

• Steel and Composite Structures
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• 제36권4호
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• pp.399-415
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• 2020

Responses of semi-rigid frames having different degrees of semi-rigidity obtained by the nonlinear static analysis (NSA) are evaluated at specific target displacements by comparing them with those obtained by the nonlinear time-history analysis (NTHA) for scaled earthquakes. The peak ground accelerations (PGA) of the earthquakes are scaled such that the obtained peak top story displacements match with the target displacements. Three different types of earthquakes are considered, namely, far-field and near-field earthquakes with directivity and fling-step effects. In order to make the study a comprehensive one, three degrees of semi-rigidity (one fully rigid and the other two semi-rigid), and two frames having different heights are considered. An ensemble of five-time histories of ground motion is included in each type of earthquake. A large number of responses are considered in the study. They include the peak top-story displacement, maximum inter-story drift ratio, peak base shear, total number of plastic hinges, and square root of sum of the squares (SRSS) of the maximum plastic hinge rotations. Results of the study indicate that the nonlinear static analysis provides a fairly good estimate of the peak values of top-story displacements, inter-story drift ratio (for shorter frame), peak base shear and number of plastic hinges; however, the SRSS of maximum plastic hinge rotations in semi-rigid frames are considerably more in the nonlinear static analysis as compared to the nonlinear time history analysis.

• 한국방재학회 논문집
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• 제11권1호
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• pp.7-13
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• 2011

지진에 대한 장대 교량의 정확한 반응 해석은 지진 방재에 있어서 중요한 역할을 한다. 본 논문은 비동기 다지지점 지진입력에 의한 교량의 반응을 진동수 영역방법과 시간 영역방법으로 해석하였으며 그 결과를 동기 입력 결과와 비교하였다. 시간영역방법에서는 선형모드 중첩 법으로 최대반응 값을 계산하였다. 진동수영역방법에서는 선형랜덤진동 이론을 사용하여 교량 성능에 영향을 미치는 모드와 다지지점 지진입력의 상호상관관계를 고려한 반응의 제곱평균근(RMS값)을 계산하였다. 교량 성능 반응 중, 변위 및 부재의 내력에 대한 시간 영역해석 결과와 진동수영역 해석 결과로부터 최대반응 값과 RMS값의 비로 정의된 최대반응 계수의 실용적인 값과 계산 방법을 요약하였다. 신뢰 있는 최대 반응계수가 있으면, 교량의 성능기반설계에서 구체적인 임의의 입력을 고려한 시간영역방법보다 결과의 일반성 및 수치적인 장점을 갖은 진동수영역방법이 더 효율적이다.

• Genomics & Informatics
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• 제18권4호
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• pp.42.1-42.9
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• 2020

Chromatin immunoprecipitation coupled with high-throughput DNA sequencing (ChIP-Seq) is a powerful technology to profile the location of proteins of interest on a whole-genome scale. To identify the enrichment location of proteins, many programs and algorithms have been proposed. However, none of the commonly used peak calling programs could accurately explain the binding features of target proteins detected by ChIP-Seq. Here, publicly available data on 12 histone modifications, including H3K4ac/me1/me2/me3, H3K9ac/me3, H3K27ac/me3, H3K36me3, H3K56ac, and H3K79me1/me2, generated from a human embryonic stem cell line (H1), were profiled with five peak callers (CisGenome, MACS1, MACS2, PeakSeq, and SISSRs). The performance of the peak calling programs was compared in terms of reproducibility between replicates, examination of enriched regions to variable sequencing depths, the specificity-to-noise signal, and sensitivity of peak prediction. There were no major differences among peak callers when analyzing point source histone modifications. The peak calling results from histone modifications with low fidelity, such as H3K4ac, H3K56ac, and H3K79me1/me2, showed low performance in all parameters, which indicates that their peak positions might not be located accurately. Our comparative results could provide a helpful guide to choose a suitable peak calling program for specific histone modifications.

• 비파괴검사학회지
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• 제33권6호
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• pp.505-510
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• 2013

An encircling send-receive type pulsed eddy current (PEC) probe is designed for use in aluminum tube inspection. When bare receive coils located away from the exciter were used, the peak time of the signal did not change although the distance from the exciter increased. This is because the magnetic flux from the exciter coil directly affects the receive coil signal. Therefore, in this work, both the exciter and the sensor coils were shielded in order to reduce the influence of direct flux from the exciter coil. Numerical simulation with the designed shielded encircling PEC probe showed the corresponding increase of the peak time as the sensor distance increased. Ferrite and carbon steel shields were compared and results of the ferrite shielding showed a slightly stronger peak value and a quicker peak time than those of the carbon steel shielding. Simulation results showed that the peak value increased as the defect size (such as depth and length) increased regardless of the sensor location. To decide a proper sensor location, the sensitivity of the peak value to defect size variation was investigated and found that the normalized peak value was more sensitive to defect size variation when the sensor was located closer to the exciter.

• 한국지능시스템학회논문지
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• 제23권1호
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• pp.72-79
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• 2013

본 논문에서는 태양광 발전시스템의 최대전력점을 추종하기 위해, 개방회로전압과 가까운 첫 번째 지역극대전력점(local peak power point)의 전압 및 전류값이 특정한 범위 내에 있을 경우, 첫 번째 지역극대점이 전역극대전력점(global peak power point)인지 판단할 수 있도록 패턴을 분석하였다. 직-병렬 어레이로 연결된 태양전지 모듈에 부분그늘문제(partial shading problem)가 발생할 경우 다수의 지역극대전력점이 관찰될 수 있어, 전역극대전력점을 찾는데 어려움이 있다. 부분선형 태양전지 모델을 이용한 태블로 해석(Tableau analysis)으로 태양전지 어레이 회로의 V-I 특성을 시뮬레이션하여 지역극대전력점과 전역극대전력점을 확인하고, 그에 해당하는 전압 및 전류 값과 V-I 특성곡선의 패턴을 분석하였다. 분석된 패턴을 통해 특정한 영역을 설정하여 첫 번째 지역극대전력점이 전역극대전력점 인지 판단하여 발전하는 경우, 첫 번째 지역극대전력점으로만 발전했을 때에 비해 효율이 향상되었다.