• Journal of Korean Society on Water Environment
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• v.25 no.3
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• pp.425-431
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• 2009

It is very important to know the probability distribution of water-quality constituents for water-quality control and management of rivers and reservoirs effectively. The probability distribution of BOD in Anseong Stream was analyzed in this paper using Kolmogorov-Smirnov test which is widely used goodness-of-fit method. It was known that the distribution of BOD in Anseong Stream is closer to Log-normal, Gamma and Weibull distributions than Normal distribution. Normal distribution can be partially applied depending on significance level, but Log-normal, Gamma and Weibull distributions can be used in any significance level. Also the estimated Log-normal distribution of BOD at Jinwi3 station was to be compared with the measured in 2001, 2002 and 2003 years. It was revealed that the estimated probability distribution of BOD at Jinwi3 follows a theoretical distribution very well. The applicable probability distribution of BOD can be used to explain more rigorously and scientifically the achievement or violation of target concentration in TMDL(Total Maximum Daily Load).

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.341-342
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• 1996

We present here the solar LOG GF values obtained using the Liege solar at las and the standard solar photospheric models for the spectral lines in the wavelength range ${\lambda}{\lambda}$ 6209 - 6273 ${\AA}$. These log gf values shall be used to interpret a high resolution spectra of the star $\gamma$ Draconics.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.209-216
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• 2014

The efficiency of gamma irradiation (0, 1, 5, 10, 15, 20, and 30 kGy) as a sterilization method of corn samples (30 g) artificially contaminated with Fusarium moniliforme stored at normal condition ($25^{\circ}C$ with approximate relative humidity (RH) of 55%) and optimal condition ($25^{\circ}C$ with a controlled RH of 97%) was studied. The results showed that the fungal growth and the amount of fumonisin were decreased as the dose of gamma irradiation increased. Gamma irradiation at 1-5 kGy treatment significantly inhibited the growth of F. moniliforme by 1-2 log reduction on corn samples (P < 0.05). Sublethal effect of gamma irradiation was observed at 10-20 kGy doses after storage, and a complete inactivation required 30 kGy. Fungal growth and fumonisin production increased with higher humidity and longer storage time in all corn samples. This study also demonstrated that there was no strict correlation between fungal growth and fumonisin production. Storage at normal condition significantly resulted in lower growth and fumonisin production of F. moniliforme as compared with those stored at optimal condition (P < 0.05). Gamma irradiation with the dose of ${\geq}5$ kGy followed by storage at normal condition successfully prolonged the shelf life of irradiated corns, intended for human and animal consumptions, up to 7 weeks.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.396-401
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• 2000

The effect of gamma-irradiation on quality changes of Samjang, Korean traditional seasoned soy paste, was studied. Samjang was prepared, irradiated at 0, 2.5, 5, 10 kGy, and then stored at $25^{\circ}C$ and $37^{\circ}C$, respectively. Non-irradiated control, sample 2%- ethanol added and sample heated at $80^{\circ}C$ for 30 min were prepared with the same conditions to be compared. The results showed that yeasts were completely eliminated by gamma-irradiation with dose at 2.5 kGy or more, and total bacteria decreased by 5 log cycles with doses at 10 kGy, showing a significant decrease during storage. The gamma irradiation treatment showed repressive effect on the swelling by gas production and browning formation of Samjang during storage. Also, the indicators of enzyme activity, such as amino nitrogen, protease activity and pH change in the gamma irradiation treatment were more stable than control. The sensory evaluations showed that irradiated samples were more acceptable. Therefore, it was considered that gamma irradiation was effective for processing Samjang and for maintaining better quality during subsequent storage.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.09a
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• pp.3-10
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• 2002

The strong ground motion data recorded in the Sino-Korea Craton are analysed toobtain attenuation relations valid for 5 < M < 8, r < 400 km applicable to the Korean Peninsula. The result is logA : -1.83+0.386M- log${\gamma}$-0.0015${\gamma}$ where A is peak horizontal acceleration in g, M is surface-wave magnitude, and r is hypocentral distance in km. Our result is compared with the existing attenuation relations of Western North America and Eastern North America and the prior predictive equations for the Southern part of Korean Peninsula. Our result compares better with those of North America than those of the Southern part of the Korean Peninsula. More theoretical and empirical studies are required for better attenuation relations appropriate for the Korean Peninsula.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.5
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• pp.867-876
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• 2023

In this study, the attributes of the NHPP software development cost model applying the Gamma family distribution (Erlang, Log-Logistic, Rayleigh) were newly analyzed, and after comparing with the Goel-Okumoto basic model to verify the properties of the model, the optimal model was also presented based on this. To analyze software reliability, failure time data that occurred randomly during system operation was used, and the calculation of the parameters was solved using the maximum likelihood estimation. As a result of comprehensive evaluation through various attribute analysis (mean value function, development cost, optimal release time), it was confirmed that the Rayleigh model had the best performance. Through this study, the attributes of the software development cost model applying the Gamma family distribution, which has no previous research case, were newly identified. Also, basic design data could also be presented so that developers can efficiently utilize this research data at an early stage.

• Journal of the Korean Mathematical Society
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• v.43 no.4
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• pp.815-828
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• 2006

Let {$V_{nk},\;k\;{\geq}\;1,\;{\geq}\;1$} be an array of rowwise independent random elements which are stochastically dominated by a random variable X with $E\|X\|^{\frac{\alpha}{\gamma}+{\theta}}log^{\rho}(\|X\|)\;<\;{\infty}$ for some ${\rho}\;>\;0,\;{\alpha}\;>\;0,\;{\gamma}\;>\;0,\;{\theta}\;>\;0$ such that ${\theta}+{\alpha}/{\gamma}<2$. Let {$a_{nk},k{\geq}1,n{\geq}1$) be an array of suitable constants. A complete convergence result is obtained for the weighted sums of the form $\sum{^\infty_k_=_1}\;a_{nk}V_{nk}$.

• Proceedings of the Korea Water Resources Association Conference
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• 1989.07a
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• pp.3-3
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• 1989

한발에 대한 정도와 기간을 예측하기위한 추계학적인 한 방법으로서 RUNS의 이론이 오래전부터 사용되고 있다. 본 연구의 목적은 이러한 RUNS 이론을 이용하여 우리나라의 강수량 형태를 년과 월로 구분하고 NORMAL, LOG-NORMAL, GAMMA 등의 이론적 분포와 비교, 분석 하여 실제 우리나라 강우량 특성이 이들 이론적 분포함수, 모멘트, 기타 다른 통계적 특성들과 어떠한 관계에 있는지 조사하는 것이다. 비교적 그 기간이 긴 대구, 부산, 서울, 전주등 8개 지점의 자료로부터 년 강수량은 정규분포, 대수정규분포, GAMMA 분포의 가정하에 그리고 월 강수량은 자료를 1차 표준화하여 우리나라 강수량의 RUNS 특성, 즉 RUN-LENGTH, RUN-SUM, RUN-INTENSITY 을 분석해 본 결과 대체로 GAMMA 분포에 가까운 경향을 보일수 있었다.

• Journal of Mechanical Science and Technology
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• v.17 no.8
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• pp.1226-1233
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• 2003

Experimental heat transfer data for single-phase water flow in the annuli with corrugated inner tubes are presented. In the annuli with parallel flow, ten different annular arrangements are considered. For water flow rate in 1,700${\gamma}$$\^$*/). As P/e becomes closer to 8 in the range below the radius ratio (${\gamma}$$\^$*/) of 0.5, Nusselt numbers increase. However, Nusselt numbers decrease in the range above the radius ratio (${\gamma}$$\^$*/) of 0.5 because flow reattachment position becomes farther in the narrower clearance.

• Water for future
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• v.29 no.1
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• pp.129-139
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• 1996

It is very important to select appropriate distributions for hydrological data in planning and designing hydraulic structures. Also, it is necessary to check whether the selected distribution reproduces the statistical characteristics of the real data. In this study, the parameters of the two- and three-parameter gamma, two- and three-parameter lognormal, Gumbel, two- and three-parameter log-Gumbel, GEV, log-Pearsonn type III, two- and three-parameter Weibull, four- and five-parameter Wakeby distributions were estimated for the rainfall data of 22 sites in Korea with 7 different durations based on the methods of moments, probability weighted moments, and maximum likelihood. And the validity conditions were checked for the estimated parameters. The separation effect for each distribution was examined throught 10,000 simulations using the estimated parameters. As results, the separation effect was the smallest: log-Pearson type III for moment method, log-Pearson type III and GEV for probability weighted moment method, and GEV for maximum likelihood method. However, it is large for the two-parameter distributions.