• 한국수산과학회지
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• 제12권4호
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• pp.245-253
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• 1979

고등어, 전어 및 정어리육을 $10^{\circ}C$와 $25^{\circ}C$에서 저장하였을 때의 육중의 TMAO-N, TMA-N 및 DMA-N의 경시적인 변화와 아울러 이들 어육을 염장, 열풍건조, 일건 및 자건하였을 때의 변화에 대하여 실험하여 다음과 같은 결과를 얻었다. 1. TMAO의 변화에 있어서, $10^{\circ}C$, 5일 저장의 경우 고등어, 전어 및 정어리는 각각 생시료때의 $15\%\;20\%$ 및 $10\%$의 잔재율을 나타내었고 $25^{\circ}C$ 1일 저장의 경우 각각 $30\%,\;26\%$ 및 $30\%$ 였다. 2. TMA의 변화는 $10^{\circ}$, 5일 저장의 경우, 고등어, 전어 및 정어리가 각각 생시료때의 4.1배, 24배 및 9.5배의 증가를 보였고 $25^{\circ}C$, 1일 저장의 경우는 각각 2.7배, 11배 및 5배였다. 3. DMA의 변화는 $10\%$, 5일 저장의 경우 고등어, 전어 및 정어리가 각각 생시료때의 7배, 25배 및 8배의 증가를 나타냈고 $25^{\circ}C$, 1일 저장의 경우는 각각 7배, 21배 및 2배였다. 4. 제품별 TMAO의 함량은 고등어, 전어의 경우 염장품>일건품>열풍건조품의 순이 였고 정어리의 경우는 자건품>염장품>열풍건조품>일건품의 순이 였다. 5. 제품별 TMA의 함량은 고등어, 전어의 경우 일건품>열풍건조품>염장품의 순이었고 정어리의 경우는 일건품>열풍건조품>염장품>자건품의 순이였다. 6. 제품중의 DMA의 함량은 고등어, 전어의 경우 일건품>염장품>열풍건조품>자건품의 순이였다. 본 연구의 실험을 도와 준 공양숙, 오영선 양에게 감사를 드리는 바이다.

• 한국식품영양과학회지
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• 제22권4호
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• pp.465-469
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• 1993

김치의 부재료로 쓰이는 멸치젓과 새우젓의 수분함량은 각각 31.14~39.01% 및 30.33~36.59%이고 밑반찬용으로 쓰이는 꼴뚜기젓, 모치젓 및 석화젓 등은 50%정도였다. 지방함량은 멸치젓이 5.51~5.85%로 가장 높았고 모치젓, 석화젓, 꼴뚜기젓 및 새우젓의 순이었다. 젓갈의 지방산 조성비는 시료에 따라 달랐지만 주요 지방산은 $C_{l6:0}$, $C_{20:5}$, $C_{l6:1}$, $C_{22:6}$, 및 $C_{l8:1}$ 등이었고, n-3 고도불포화지방산 비율이 높은 시료로는 꼴뚜기젓이 39.11%로 가장 높았고, 새우젓, 석화젓, 멸치젓 및 모치젓의 순이었다. n-3 고도불포화지방산 중에서 EPA는 비교적 석화젓(17.71%)과 꼴뚜기젓(16.38%)이 높았으며 DHA는 꼴뚜기젓(22.22%)과 새우젓 (15.13~21.50%)이 높았으나 특히 모치젓은 가장 낮은 함량을 보였다.보였다.

• Steel and Composite Structures
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• 제7권4호
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• pp.339-354
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• 2007

Arched Corrugated Steel Roof (ACSR) is a kind of thin-walled steel shell, composing of arched panels with transverse small corrugations. Four full-scale W666 ACSR samples with 18m and 30m span were tested under full and half span static vertical uniform loads. Displacement, bearing capacities and failure modes of the four samples were measured. The web and bottom flange in ACSR with transverse small corrugations are simplified to anisotropic curved plates, and the equivalent tensile modulus, shear modulus and Poisson's ratio of 18m span ACSR were measured. Two 18 m-span W666 ACSR samples were analyzed with the Finite Element Analysis program ABAQUS. Base on the tests, the limit bearing capacity of ACSR is low, and for half span loading, it is 74-75% compared with the full span loading. When the testing load approached to the limit value, the bottom flange at the sample's bulge place locally buckled first, and then the whole arched roof collapsed suddenly. If the vertical loads apply along the full span, the deformation shape is symmetric, but the overall failure mode is asymmetric. For half span vertical loading, the deformation shape and the overall failure mode of the structure are asymmetric. The ACSR displacement under the vertical loads is large and the structural stiffness is low. There is a little difference between the FEM analysis results and testing data, showing the simplify method of small corrugations in ACSR and the building techniques of FEM models are rational and useful.

• Animal Systematics, Evolution and Diversity
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• 제5권1호
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• pp.1-12
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• 1989

한국 남서연안및 섬등의 8개지역에서 등줄쥐((Apodemus agraris)의 표본들을 채접하였다. 한반도의 여타지역벚 제주도의 표본틀과 같이 두골벚 외부측청치를 포함하는 형태적형질의 분석과 염색체 핵형의 비교분석을 실시하였다. 염색체 분석에 있어서 한국내의 표본들간에 핵형상의 차이는 없었다. 형태적 형질의 분석에 있어서 완도및 보걸도에서 채집된 표본들은 제주도의 표본들과 함께 large-size group (큰형)을 형성했다(Apodemus agrarius chejuensis). 반면에 진도빛 하조도의 표본들은 남서 연 안을 포함하는 한반도지 역 에 서 채 집 된 표본등 과 함께 small-size group (작은 형)을 이루였다(A. agrarius comeae). 완도및 보걸도에 큰 형의 등줄쥐플이 현재 서식하고 있는 이유는 전에 살았던 작은 행의 등줄쥐들이 전멸되고, 제주도로 부터 언간에 의해서 이주된 큰 형의 등줄쥐들로 대체되었기 때문이라고 추정하였다

• Communications for Statistical Applications and Methods
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• 제5권2호
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• pp.517-529
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• 1998

When the sample size is small the robust minimum Hellinger distance (HD) estimator can have substantially poor relative efficiency at the true model. Similarly, approximating the exact null distributions of the ordinary Hellinger distance tests with the limiting chi-square distributions can be quite inappropriate in small samples. To overcome these problems Harris and Basu (1994) and Basu et at. (1996) recommended using a modified HD called penalized Hellinger distance (PHD). Lindsay (1994) and Basu et al. (1997) showed that another density based distance, namely the negative exponential disparity (NED), is a major competitor to the Hellinger distance in producing an asymptotically fully efficient and robust estimator. In this paper we investigate the small sample performance of the estimates and tests based on the NED and penalized NED (PNED). Our results indicate that, in the settings considered here, the NED, unlike the HD, produces estimators that perform very well in small samples and penalizing the NED does not help. However, in testing of hypotheses, the deviance test based on a PNED appears to achieve the best small-sample level compared to tests based on the NED, HD and PHD.

• 통합자연과학논문집
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• 제14권3호
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• pp.123-129
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• 2021

This research examines the effect of positively skewed population distribution on the two sample t-test through simulation. For simulation work, two independent samples were selected from the same chi-square distributions with 3, 5, 10, 15, 20, 30 degrees of freedom and sample sizes 3, 5, 10, 15, 20, 30, respectively. Chi-square distribution is largely skewed to the right at small degrees of freedom and getting symmetric as the degrees of freedom increase. Simulation results show that the sampled populations are distributed positively skewed like chi-square distribution with small degrees of freedom, the F-test for the equality of variances shows poor performances even at the relatively large degrees of freedom and sample sizes like 30 for both, and so it is recommended to avoid using F-test. When two population variances are equal, the skewness of population distribution does not affect on the t-test in terms of the confidence level. However even though for the highly positively skewed distribution and small sample sizes like three or five the t-test achieved the nominal confidence level, the error limits are very large at small sample size. Therefore, if the sampled population is expected to be highly skewed to the right, it will be recommended to use relatively large sample size, at least 20.

• 한국군사과학기술학회지
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• 제22권5호
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• pp.724-734
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• 2019

This study selected a representative small arm firing range and analyzed the distribution of heavy metal pollutants such as Pb, Cu, Zn, etc. For this the concentrations of heavy metals in soils, roots and leaves of plants, and water of the small arm firing range were measured. The concentrations of heavy metals in the effluent were also checked during precipitation. The concentration of lead in the samples collected from the top soil(0-5 cm) and sub soil(5-50 cm) near the target in the small arm firing range exceeded the concern level of the Soil Environment Conservation Act of Korea, but not in other soil samples. Plants that grow in soil heavily contaminated with lead showed a high lead concentration, especially in roots. However, the concentration of lead in effluent from the small arm firing range was less than 0.02 ppm. The concentration of copper and zinc in the small arm firing range did not surpass the concern level of the Soil Environment Conservation Act of Korea. Through this study more accurate information on the distribution of heavy metal pollution in the soil of the small arm firing range was obtained. Based on this research, we can conclude that some facility improvements can reduce the spreading of pollutants in the currently used small arm firing range and contribute to the design and operation of advanced small arm firing ranges.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.139-146
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• 2001

Undrained triaxial tests were peformed for a weathered soil, which includes local measurement using LVDT The behavior from small In large strain conditions could be evaluated consistently through a triaxial test, The stress-strain relationship of undisturbed samples were compared with the disturbed and the shear moduli in the small strain level had the almost same values. Especially the shear moduli were mostly affected by the initial condition of water contents. An anisotropic hardening model based on the total stress concept could predict the stress-strain relationship accurately, which makes it possible to analyze the geotechnical problem reasonably for the weathered soil.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제2권1호
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• pp.41-60
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• 1998

This paper derives a consistent and bias corrected extension of Akaike's Information Criterion (AIC), $AIC_{bc}$, based on Kullback-Leibler information. This criterion has terms that penalize the overparametrization more strongly for small and large samples than that of AIC. The overfitting problem of the asymptotically efficient model selection criteria for small and large samples will be overcome. The $AIC_{bc}$ also provides a consistent model order selection. Thus, it is widely applicable to data with small and/or large sample sizes, and to cases where the number of free parameters is a relatively large fraction of the sample size. Relationships with other model selection criteria such as $AIC_c$ of Hurvich, CAICF of Bozdogan and etc. are discussed. Empirical performances of the $AIC_{bc}$ are studied and discussed in better model order choices of a linear regression model using a Monte Carlo experiment.

• Journal of electromagnetic engineering and science
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• 제4권1호
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• pp.23-29
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• 2004

In this paper we analyze convergence constraints and time constant of IT-LMS algorithm and derive a method of making it's time constant independent of signal power by using input variance estimation. The method for estimating the input variance is to use a single-pole low-pass filter(LPF) with common smoothing parameter value, θ. The estimator is with narrow bandwidth for large θ but with wide bandwidth for small θ. This small θ gives long term average estimation(low frequency) of the fluctuating input variance well as short term variations (high frequency) of the input power. In our simulations of multipath communication channel equalization environments, the method with large θ has shown not as much improved convergence speed as the speed of the original IT-LMS algorithm. The proposed method with small θ=0.01 reach its minimum MSE in 100 samples whereas the IT-LMS converges in 200 samples. This shows the proposed, tap-power normalized IT-LMS algorithm can be applied more effectively to digital wireless communication systems.