• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2005년도 학술발표회(1)
• /
• pp.259-260
• /
• 2005

• 대한수학회지
• /
• 제33권3호
• /
• pp.469-479
• /
• 1996

Toric variety is a normal algebraic variety containing algebraic torus $T_N$ as an open dense subset with an algebraic action of $T_N$ which is an extension of the group law of $T_N$. A toric variety can be described in terms of a certain collection, which is called a fan, of cones. From this fact, the properties of a toric variety have strong connection with the combinatorial structure of the corresponding fan and the relations among the generators. That is, we can translate the diffcult algebrogeometric properties of toric varieties into very simple properties about the combinatorics of cones in affine spaces over the reals.

• Journal of the Korean Data and Information Science Society
• /
• 제14권4호
• /
• pp.1067-1082
• /
• 2003

In this paper, we propose a randomized response model with discrete quantitative attribute by three-stage cluster sampling for obtaining discrete quantitative data by using the Liu & Chow model(1976), when the population was made up of sensitive discrete quantitative clusters. We obtain the minimum variance by calculating the optimum number of fsu, ssu, tsu under the some given constant cost. And we obtain the minimum cost under the some given accuracy.

• 한국데이터정보과학회:학술대회논문집
• /
• 한국데이터정보과학회 2004년도 추계학술대회
• /
• pp.25-32
• /
• 2004

In this study, we use various change-point detection methods to detects Korea economic crisis of 1997, and then compares their performance. In change-point detection method, there are three major categories: (1) the parametric approach, (2) the nonparametric approach, and (3) the model-based approach. Through the application to Korea foreign exchange rate during her economic crisis, we compare the employed change-point detection methods and, furthermore, determine which of them performs better.

• Journal of the Korean Data and Information Science Society
• /
• 제15권3호
• /
• pp.585-592
• /
• 2004

This study detects Korea economic crisis of 1997 using various change-point detection methods and then compares their performance. In change-point detection method, there are three major categories: (1) the parametric approach, (2) the nonparametric approach, and (3) the model-based approach. Through the application to Korea foreign exchange rate during her economic crisis, we compare the employed change-point detection methods and, furthermore, determine which of them performs better.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2003년도 추계학술대회 논문집(III)
• /
• pp.500-506
• /
• 2003

Dopper should performance not only to constrain rolling and yawing system but also to develop capability of pantograph. In orde to get purpose, the survey and study that the type of dropper which convert 'I' type dropper into 'Y' type that performance to constrain rolling,yawing and jamping of catenary system simultaneously.

• 천문학논총
• /
• 제30권2호
• /
• pp.225-227
• /
• 2015

We introduce a code called tlc_s05, to fit sparsely sampled JHK band Cepheid light curve data with template light curves to derive the mean magnitude. A brief description of the code is provided here. We tested the performance of the code in deriving the mean JHK band magnitudes using simulations, and we found that it is better to observe more than four evenly spaced data points per light curve, which permits tlc_s05 to derive accurate mean magnitudes for Cepheid JHK band light curves.

• 융합신호처리학회논문지
• /
• 제6권2호
• /
• pp.100-106
• /
• 2005

OFDM은 심볼간 간섭에 대한 강인성으로 인하여 4세대 광대역 이동통신에 적합한 변조방식으로 활발히 연구되고 있다. OFDM 전송 기술은 신호 대 잡음비에 따라서 각 부반송파의 변조기법을 적응적으로 적용할 수 있다. 본 논문에서는 광대역 이동 채널에서 OFDM 시스템을 위한 적응적 변조기법을 제안하였다. 제안한 알고리즘은 목표 BER의 SNR 임계값을 이용하여 각 부반송파에 초기 비트를 할당하고, Chow 알고리즘을 적용하여 전체 비트수를 목표 비트수와 같게 제어한다. 또한, 제안한 알고리즘은 부반송파들을 블록으로 구성함으로써 부반송파의 비트할당을 위한 시그날링 오버헤드를 줄였다. 제안한 알고리즘은 광대역 이동채널에서 블록내의 부반송파의 수, 목표 BER, 그리고 도플러 주파수에 대한 적응형 OFDM 시스템의 성능을 평가하였다.

• 물과 미래
• /
• 제19권1호
• /
• pp.75-86
• /
• 1986

본연구는 하천유역에 있어서, 대규모 수공구조물의 설계홍수량 결정을 위한 최대가능강우량(PMP)분석 및 적용에 그 목적이 있다. PMP는 수문기상학적 방법,통계학적 방법, 포락선 방법으로 산정하였으며, 최대가능홍수량(PMF)은 합성단위도법과 Chow 방법으로 산정하였다. 각 방법에 의한 PMP를 비교해 본 결과, 통계학적 방법, 수문기상학적 방법, 포락선 방법의 크기 순으로 나타나고 있음을 알 수 있었으며, 산정된 PMP를 기왕의 최대강우량과 비교해 본 결과 수문기상학적 방법이 기상학적 제요소를 고려한 방법이 가장 타당한 방법이라고 사료된다. 산정된 PMP 및 PMF를 확률 수문량과 비교해 본 결과 수문기상학적 방법 및 통계학적 방법은 재현기간 1000년 확률 수문량을 다소 상회하는 것으로 나타났으며, 포락선 방법은 재현기간 200∼500 년 확률 수문량에 접근하고 있음을 알 수 있었다.대규모 수공 구조물의 설계에 있어서 위험도를 고려할 경우에는 PMP로부터 PMF를 산정하는 것이 타당할 것이다.

• Journal of Nutrition and Health
• /
• 제29권10호
• /
• pp.1087-1095
• /
• 1996

The study was carried out to investigate a new type of functional foods with hypotensive effect which is critical in the prevention and treatment of hypertension and related circulatory diseases. The experimental diets(A, B, C) were prepared from plant based ingredients such as buckwheat, potato, perilla seed with different ratios formulated as an edible form appropriate for human consumption according to AIN-77 standard. Control group(D) was fed commercial rat chow. Twety-four 15-week-old SDR(Sprague Dawley rats) and twenty-four 20-week-old SHR(spontaneously hypertensive rats), weighing 200g respectively, were assigned to 4 treatments of 6 rats each in a completely randomized design. Blood pressure was measured at 7 day interval by tail-cuff sphygmomanometer using an IITC cuff pump and amplifier. The growth rates of both SHR and SDR were not statistically different in comparions with the control except those of diet B and C in SDR and SHR, respectively(p<0.05). When exprimental diets were fed, systolic blood pressure of SDR and SHR at day 28 had been lowered by 17-20 mmHg(ave. of 19.6mmHg for both strains) compared with the reference pressure at day 0. The levels of HDL-cholesterol were increased, while the levels of LDL-cholesterol consistently decreased in both strains when experimental diets were fed(p<.05). Plasma total cholesterol levels were not different among treatments. Plasma triglyceride levels were higher in control diet(commercial rat chow) due to two times higher fat content of control diet itself(p<.05). Atherogenic indices were lower compared to those of control when the experimental diets were fed in both strains (p,.05). The results suggest that the antihypertensive diets mainly consisting of plant-based ingredients may possibly effective in relieving hypertension as well as circulatory diseases.