• Communications for Statistical Applications and Methods
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• 제10권1호
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• pp.211-224
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• 2003

Good's lambda test, a permutation test used to detect the changes of microorganism composition under two pathological conditions, has been quite popular for studying the micro-flora responsible for periodontal disease. A vast number of different micro-flora in the mouth renders the traditional chi-square test inapplicable. The main purpose of this paper is to evaluate the power of this test so that the sample size can be determined at the design stage. The robustness of this test and its comparison to two other intuitive tests are also presented. It is found that a permutation test based on likelihood ratio is more powerful than the lambda test in our simulated cases.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.179-180
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• 2009

기존의 장면전환 검출의 문제점들을 줄이고 복잡하고 다양한 실세계의 영상변화를 가장 일반적이고 표준화된 방법으로 분석하고 분할하며 표현할 수 있는 기법을 제안하고자 한다. 본 논문에서는 새로운 로컬 컬러 ${\lambda}^2$-테스트를 제한하는데 이는 기존의 ${\lambda}^2$-테스트와 로컬 컬러 히스토그램을 결합한 방법이다. 이 방법은 급진적 장면전환과 점진적 장면전환을 모두 검출할 수 있는 강건한 방법을 제시하여 기존에 장면전환 검출 방법이 안고 있던 문제를 해결하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.146-146
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• 2000

This paper presents field test results of the GPS precise positioning using carrier phase observable. The Least-squares AMBiguity Decorrelation Adjustment(LAMBDA) method is implemented to resolve integer ambiguity problem for two epoch Ll carrier phase measurement data. Field test results show that the GPS precise positioning of cm-level accuracy is obtainable with conventional low cost, single frequency C/A code GPS receivers.

• Journal of the Korean Data and Information Science Society
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• 제4권
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• pp.137-146
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• 1993

The Proposed goodness-of-fit test Statistic $\hat{\lambda}_{\alpha}$ derived from the test Statistc in Kim (1992) is itself a smoothing parameter which is selected to minimize an estimated MISE for a truncated series estimator, $d_{\hat{\lambda}{n}}$, of the comparison density function. Therefore, this test statistic leads immediately to a point estimate of the density function in the event that $H_{0}$ is ejected. The limiting distribution of $\hat{\lambda}_{\alpha}$ was obtained under the null hypothesis. It is also shown that this test is consistent against fixed alternatives.

• Communications for Statistical Applications and Methods
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• 제2권1호
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• pp.122-136
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• 1995

The objective of this research is to investigate the problem of goodness-of-fit testing based on nonparametric density estimation with a data-driven smoothing parameter. The small and large sample properties of a new test statistic $\hat{\lambda_a}$ is investigated. The test statistic $\hat{\lambda_a}$ is itself a smoothing parameter which is selected to minimize an estimated MISE for a truncated series estimator of the comparison density function. Therefore, this test statistic leads immediately to a point estimate of the density function th the event that $H_0$ is rejected. The limiting distribution of $\hat{\lambda_a}$ is obtained under the null hypothesis. It is also shown that this test is consistent against fixed alternatives.

• 한국광학회지
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• 제3권1호
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• pp.20-26
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• 1992

Twyman-Green형 간섭계의 시험파면의 변형을 추출하기 위하여 fourier변환을 이용하는 방법을 모사실험과 실험을 통하여 검토하였다. 대상 방법중에서는 Takeda의 방법이 변형을 추출하는 용도로 적절함이 밝혀졌다. 이 방법을 평면경에 적용하여 얻은 표면의 구조에는 curvature가 존재하며, 그 크기는 $\lambda$/6정도였다. 이 축정의 정확도는 $\lambda$/40정도로 얻어져, 기 발표된 유사연구의 결과보다 그 정도가 높음을 확인하였다.

• ETRI Journal
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• 제31권1호
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• pp.68-70
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• 2009

In this letter, a parametric analysis of the Fresnel-field antenna measurement method is performed for a square aperture. As a result, the optimum number of Fresnel fields for one far-field point is guided as $M_{opt}=N_{opt}=D^2/{\lambda}R+5$, where D is the antenna diameter, ${\lambda}$ is the wavelength, and R is the distance between the source antenna and the antenna under test. For the aperture size 5 ${\leq}$ $L_x/{\lambda}$ ${\leq}$ 20, the tolerable distances for gain errors of 0.5 dB and 0.2 dB can be guided as $R_{0.5\;dB}$ ${\approx}$ $1.2Lx/{\lambda}$ and $R_{0.2\;dB}$ ${\approx}$ $2.0L_x/{\lambda}$, where $L_x$ is the lateral length of the square aperture. The tolerable distances for 20 ${\leq}$ $L_x/{\lambda}$ ${\leq}$ 200 are also proposed. This measurement guideline can be fully utilized when performing the Fresnel-field antenna measurement method.

• 농약과학회지
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• 제3권1호
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• pp.57-65
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• 1999

세계적으로 환경생태독성의 주요지표종으로 저니토독성시험에 주로 이용되는 깔따구(Chironomus riparius)를 이용하여 물만으로한 시험계와 물과 토양이 공존하는 시험계 사이의 $^{14}C$-lambda-cyhalothrin의 생물학적인 독성과 농약잔류양상의 차이를 비교하였다. 물과 토양이 공존하는 시험계에서는 물중 lambda-cyhalothrin 잔류량이 약제처리후 5일에서 처음 처리 농도의 99%이상이 감소하는 것으로 나타났으나 물만을 처리한 시험계에서는 처음농도의 약 35%가 감소하였다. Lambda-cyhalothrin의 Chironomus riparius에 대한 독성시험에서 물만 있는 용기에서와 물과 토양이 공존하는 시험계에서의 72시간 $LC_{50}$이 각각 $0.156{\mu}g/{\ell}$이하와 889 ${\mu}g/kg$으로 물과 토양이 공존하는 용기에서의 독성이 약 5,000배 이상 낮은 것으로 나타났다. 따라서 토양과 물 사이의 흡착분배계수의 차이에 의해 물 중 lambda-cyhalothrin의 잔류량이 감소하고 이에 따라 시험생물에 대한 독성도 감소함을 알 수 있었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.158-162
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• 2005

정어리에서 분리한 5개의 균주를 이용하여 antiangiogenesis 효과가 가장 뛰어난 균주를 ${\lambda}-28$이라 명명하고 이를 대량 배양하여 단백질 추출법인 염석과 투석, 동결건조를 통해 시료를 제조하여 이를 SEC를 통해 fraction별로 분리한 후 SDS-PAGE와 antiangiogenesis, cytotoxcity test를 수행하여 ${\lambda}-28$번의 76 fraction에서 control군에 비해 82.7%의 높은 antiangiogenesis 효과를 보였고, 세포독성 실험에서도 낮은 독성을 보였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.179-184
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• 2006

Rapid and high-precision positioning with a Global Navigation Satellite System (GNSS) is feasible only when very precise carrier-phase observations can be used. There are two kinds of mathematical models for ambiguity resolution. The first one is based on both pseudorange and carrier phase measurements, and the observation equations are of full rank. The second one is only based on carrier phase measurement, which is a rank-defect model. Though the former is more commonly used, the latter has its own advantage, that is, ambiguity resolution will be freed from the effects of pseudorange multipath. Galileo will be operational. One of the important differences between Galileo and current GPS is that Galileo will provide signals in four frequency bands. With more carrier-phase data available, frequency combinations with long equivalent wavelength can be formed, so Galileo will provide more opportunities for fast and reliable ambiguity resolution than current GPS. This paper tries to investigate phase only fast ambiguity resolution performance with four Galileo frequencies for short baseline. Cascading Ambiguity Resolution (CAR) method with selected optimal frequency combinations and LAMBDA method are used and compared. To validate the resolution, two tests are used and compared. The first one is a ratio test. The second one is lower bound success-rate test. The simulation test results show that, with LAMBDA method, whether with ratio test or lower bound success rate validation criteria, ambiguity can be fixed in several seconds, 8 seconds at most even when 1 sigma of carrier phase noise is 12 mm. While with CAR method, at least about half minute is required even when 1 sigma of carrier phase noise is 3 mm. It shows that LAMBDA method performs obviously better than CAR method.