• KSBB Journal
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• v.22 no.5
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• pp.297-304
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• 2007

For large and rapid screening of high-yielding mutants of lovastatin produced by filamentous fungal cells of Aspergillus terreus, one of the most important stage is to test as large amounts of mutated strains as possible. For this purpose, we intended to develop a miniaturized cultivation method using $7m{\ell}$ culture tube instead of traditional $250m{\ell}$ flask (working volume $50m{\ell}$). For obtaining large amounts of conidiospores to be used as inoculums for miniaturized cultures, 4 components i.e., glucose, sucrose, yeast extract and $KH_2PO_4$ were intensively investigated, which had been observed to show positive effect on enhancement of spore production through Plackett-Burman design experimet. When optimum concentrations of these components that were determined through application of response surface method (RSM) based on central composite design (CCD) were used, maximum spore numbers amounting to $1.9\times10^{10}$ spores/plate were obtained, resulting in approximately 190 fold increase as compared to the commonly used PDA sporulation medium. Using the miniaturized cultures, intensive strain development programs were carried out for screening of lovastatin high-yielding as well as highly reproducible mutants. It was observed that, for maximum production of lovastatin, the producers should be activated through 'PaB' adaptation process during the early solid culture stage. In addition, they should be proliferated in condensed filamentous forms in miniaturized growth cultures, so that optimum amounts of highly active cells could be transferred to the production culture-tube as reproducible inoculums. Under these highly controlled fermentation conditions, compact-pelleted morphology of optimum size (less than 1 mm in diameter) was successfully induced in the miniaturized production cultures, which proved essential for maximal utilization of the producers' physiology leading to significantly enhanced production of lovastatin. As a result of continuous screening in the miniaturized cultures, lovastatin production levels of the 81% of the daughter cells derived from the high-yielding producers turned out to be in the range of 80%$\sim$120% of the lovastatin production level of the parallel flask cultures. These results demonstrate that the miniaturized cultivation method developed in this study is efficient high throughput system for large and rapid screening of highly stable and productive strains.

• Progress in Medical Physics
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• v.18 no.2
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• pp.87-92
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• 2007

A thermal neutron beam facility utilizing a typical tangential beam port for Neutron Capture Therapy was installed at the HANARO, 30 MW multi-purpose research reactor. Mixed beams with different physical characteristics and relative biological effectiveness would be emitted from the BNCT irradiation facility, so a quantitative analysis of each component of the mixed beams should be performed to determine the accurate delivered dose. Thus, various techniques were applied including the use of activation foils, TLDs and ionization chambers. All the dose measurements were perform ed with the water phantom filled with distilled water. The results of the measurement were compared with MCNP4B calculation. The thermal neutron fluxes were $1.02E9n/cm^2{\cdot}s\;and\;6.07E8n/cm^2{\cdot}s$ at 10 and 20 mm depth respectively, and the fast neutron dose rate was insignificant as 0.11 Gy/hr at 10 mm depth in water The gamma-ray dose rate was 5.10 Gy/hr at 20 mm depth in water Good agreement within 5%, has been obtained between the measured dose and the calculated dose using MCNP for neutron and gamma component and discrepancy with 14% for fast neutron flux Considering the difficulty of neutron detection, the current study support the reliability of these results and confirmed the suitability of the thermal neutron beam as a dosimetric data for BNCT clinical trials.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.258-263
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• 2019

Near infrared reflectance spectroscopy (NIRS) has become increasingly used as a rapid and accurate method of evaluating some chemical compositions in forages. The objective of this study was to evaluate the potential of NIRS, applied to imported forage, to estimate the moisture and chemical parameters for imported hays. A population of 392 imported hay representing a wide range in chemical parameters was used in this study. Samples of forage were scanned at 1 nm intervals over the wavelength range 680-2500nm and the optical data was recorded as log 1/Reflectance(log 1/R), which scanned in intact fresh condition. The spectral data were regressed against a range of chemical parameters using partial least squares(PLS) multivariate analysis in conjunction with spectral math treatments to reduced the effect of extraneous noise. The optimum calibrations were selected based on the highest coefficients of determination in cross validation(R²) and the lowest standard error of cross-validation(SECV). The results of this study showed that NIRS predicted the chemical parameters with very high degree of accuracy. The R² and SECV for imported hay calibration were 0.92(SECV 0.61%) for moisture, 0.98(SECV 0.65%) for acid detergent fiber, 0.97(SECV 0.40%) for neutral detergent fiber, 0.99(SECV 0.06%) for crude protein and 0.97(SECV 3.04%) for relative feed value on a dry matter(%), respectively. Results of this experiment showed the possibility of NIRS method to predict the moisture and chemical composition of imported hay in Korea for routine analysis method to evaluate the feed value.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.2 s.57
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• pp.105-110
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• 2006

This study was to describe the differences in efficacy and effect of herbal extracts by the part and solvent extraction from the medical plants used as materials of oriental herbs cosmetics. And, this study was to apply to the test method of efficacy and effect related to the antioxidation as herbal extracts, complex of actual ingredient, not existing analytical methods of single ingredient. After screening the medical plants with the antioxidative activity primarily and selecting 11 sorts of medical plants to be used by the part in the literature, this study was to confirm the differences through the well-known test methods like DPPH radical scavenging activity test and hydroxyl radical scavenging activity test. For examples, in case of Trachelospermum asiaticum, compared with the aerial part and fruit, the value of DPPH radical scavenging activity test had $25.2 {\pm} 0.2$ and $62.4 {\pm}1.6$ each. It has shown that the value of fruit had 2.4 times higher effect than the one of aerial part. In case of hydroxyl scavenging activity test, it was effective in the fruit, but it has shown that there was no effect on the aerial part. It showed the same phenomena in some other plants. From the result above, this researcher could understand that it needed to consider extracting the medical plants or plants with the active principle by the part. Also, this study was to confirm the differences in effect according to the solvent as it changed the solvent extraction after selecting a plant (Lithospermum erythrorhizon) widely used for medicine and dye. As a result of measuring the actual value of superoxide scavenging activity test, this study was to consider that there were differences by the part or solvent extraction in extracting and using the medical plants as it has shown that the effect differences produced $10{\sim}80%$ according to the solvent. When it was applied to the products, this study has shown that it needed to decrease the possible errors.

• Journal of the Korean earth science society
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• v.42 no.3
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• pp.247-263
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• 2021

Climate change has been accelerating in coastal waters recently; therefore, the importance of coastal environmental monitoring is also increasing. Chlorophyll-a concentration, an important marine variable, in the surface layer of the global ocean has been retrieved for decades through various ocean color satellites and utilized in various research fields. However, the commonly used chlorophyll-a concentration algorithm is only suitable for application in clear water and cannot be applied to turbid waters because significant errors are caused by differences in their distinct components and optical properties. In addition, designing a standard algorithm for coastal waters is difficult because of differences in various optical characteristics depending on the coastal area. To overcome this problem, various algorithms have been developed and used considering the components and the variations in the optical properties of coastal waters with high turbidity. Chlorophyll-a concentration retrieval algorithms can be categorized into empirical algorithms, semi-analytic algorithms, and machine learning algorithms. These algorithms mainly use the blue-green band ratio based on the reflective spectrum of sea water as the basic form. In constrast, algorithms developed for turbid water utilizes the green-red band ratio, the red-near-infrared band ratio, and the inherent optical properties to compensate for the effect of dissolved organisms and suspended sediments in coastal area. Reliable retrieval of satellite chlorophyll-a concentration from turbid waters is essential for monitoring the coastal environment and understanding changes in the marine ecosystem. Therefore, this study summarizes the pre-existing algorithms that have been utilized for monitoring turbid Case 2 water and presents the problems associated with the mornitoring and study of seas around the Korean Peninsula. We also summarize the prospective for future ocean color satellites, which can yield more accurate and diverse results regarding the ecological environment with the development of multi-spectral and hyperspectral sensors.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.384-397
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• 2018

The aim of this study is to screen the strains of Bacillus spp. possessing safety, probiotic activity, and so on, which can be utilized as probiotic resource for using the feed and supplement food of companion animal. About 300 isolates were isolated from traditional Korean sauces, four isolates that did not have or produce the six kinds of B. cereus type vomiting and diarrhea toxin genes, ${\beta}$-hemolytic, and three kinds of carcinogenic enzymes were selected. Antibiotic gene retention, cell surface hydrophobicity, antibiotic sensitivity, and glucose utilization were analyzed for four isolates, and finally SRCM 100731 was selected. SRCM 100731 was named as Bacillus amyloliquefaciens SRCM 100731 16S rRNA sequencing analysis, and carried out optimization of cell growth for industrial applications such as pet food and feed. The effects of 14 different components on cell growth were investigated and three significant positive factors, molasses, sodium chloride, and potassium chloride were selected as the main factors based on a Plackett-Burman design. In order to find out optimal concentration on each constituent, we carried out central composite design. The predicted optimized concentrations were 7% molasses, 1.1% sodium chloride, 0.5% potassium chloride. Finally, an overall about 7-fold increase in dry cell weight yield ($12.6625{\pm}0.0658g/L$) was achieved using the optimized medium compared with the non-optimized medium ($1.8273{\pm}0.0214g/L$). This research is expected to be highly utilized in the growing pet industry by establishing optimal cultivation conditions for industrial application as well as screening Bacillus amyloliquefaciens SRCM 100731 as probiotic resource for companion animal.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.1
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• pp.111-120
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• 2017

In this paper, we propose novel feature extraction algorithm for classification of seabed sediment. In previous researches, acoustic reflection coefficient has been used to classify seabed sediments, which is constant in terms of frequency. However, attenuation of seabed sediment is a function of frequency and is highly influenced by sediment types in general. Hence, we developed a feature vector by using attenuation variation with respect to frequency. The attenuation variation is obtained by using reflected signal from the second sediment layer, which is generated by broadband chirp. The proposed feature vector has advantage in number of dimensions to classify the seabed sediment over the classical scalar feature (reflection coefficient). To compare the proposed feature with the classical scalar feature, dimension of proposed feature vector is reduced by using linear discriminant analysis (LDA). Synthesised acoustic amplitudes reflected by seabed sediments are generated by using Biot model and the performance of proposed feature is evaluated by using Fisher scoring and classification accuracy computed by maximum likelihood decision (MLD). As a result, the proposed feature shows higher discrimination performance and more robustness against measurement errors than that of classical feature.

• The Korean Journal of Applied Statistics
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• v.1 no.2
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• pp.34-44
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• 1987

In order to estimate the optimum fertilizer level for rice, a major food crop, the experimental results obtained from the fertilizer trials conducted at 642 experimental sites(farmers' fields) throughout the country for the period from 1976 to 1979 were examined. Since non-significant interactions among fertilizers have been ovserved from the past experiences, only thirteen treatments(combinations of fertilizer levels) for the experiments as given in the Table 1 were chosen such that simple response curves can be fitted with independent variables being N, $P_2O_5, and K_2O$. Weighted combining analysis of variance was also carried out for each type of paddy fields to test the significance of Treatments $\times$ Experimental sites interaction, and highly significant variability in response to treatments among experimental sites in the same type of paddy fields was observed in most types of fields. For the types of paddy fields where the treatments $\times$ experimental sites interaction was not significant, separate response curves for N, $P_2O_5, and K_2O$ were estimated on the basis of the mean yields of rice, and common values of the optimum levels of fertilizers were extimated thereform. When the interaction is significant, response curves were fitted for each experimental sites. The average fertilizer doses estimated for the types of paddy fields based on the individual sites are given in Tables 7-1 and 7-2.

• Sleep Medicine and Psychophysiology
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• v.23 no.2
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• pp.68-76
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• 2016

Objectives: To find evidence that sleep is necessary for normal brain function, thus indicating that declines in both sleep quality and quantity are related to worse performance of many daily tasks and deteriorated physical functions. The present study investigates the relationships of balance control and reaction time with sleep quality. Methods: 58 healthy (male 20, female 38) volunteers with informed consent participated in this study. The Self-reported Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality and relevant factors, and the subjects were divided into groups A (PSQI < 5) and B ($PSQI{\geq}5$) based on this index. Static balance control and reaction time to visual stimuli were conducted to assess their relationship with sleep quality. Results: Group B exhibited excessive daytime sleepiness significantly more often compared to group A. Static balance control did not markedly change relative to sleep quality, but reaction time and error to visual stimuli were significantly increased in group B compared to group A. Conclusion: These findings indicate that a decline in sleep quality can result in delayed reactions, as well as decreased accuracy of these reactions. They also suggest that low sleep quality may be associated with changes in physical functions, including balance control through reduced selective attention.

• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.111-116
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• 2007

현재 한강수계를 제외한 3대강 수계에서 수질오염총량관리제도가 의무제로써 시행되고 있다. 그러나 과학적 타당성과 외국의 성공사례들로 하여금 한강수계에 대해서도 수질오염총량제도를 의무제화 하려는 시도가 추진되고 있고 있는 실정이다. 이 제도가 한강수계에도 도입된다면, 한강권역에 포함되는 모든 지자체는 해당 유역에서 하천으로 유입되는 배출부하량을 할당받은 할당부하량 이하로 관리하여야만 정해진 유역의 목표수질을 달성할 수 있으며, 배출부하량 관리를 계획한데로 이행하지 못한 지자체는 범칙금 내지는 행정제재를 받게 된다. 따라서 체계적이고 과학적인 모니터링 및 분석 수단이 필요하다. 이 연구는 환경부 고시 한강기술지침에 의거하여 GIS를 이용하여 인천일대의 오폐수 발생부하량 및 배출부하량을 제시하고 과학적인 오염물질 삭감방안을 모색하는 것을 목적으로 진행되었다. 생활계, 산업계, 축산계, 양식계의 4 가지로 분류된 점오염원과 토지 이용 분류에 따른 비점오염원에 대한 각각의 발생부하량을 GIS를 통해 산정하고, 모든 오염원별로 처리경로를 고려하고 처리시설별, 방법별 삭감 효율을 반영하여 배출부하량을 산정하여 GIS상에서 제시하고 분석하였다. 인천일대는 인근지역에 비해 인구밀도가 높고 산업단지가 발달하여 생활계와 산업계 오염원에 의한 발생부하량 및 배출부하량이 많았으며, 특정 오염물에 대해서는 삭감 계획이 필요함을 확인할 수 있었다. 따라서 수질오염총량관리제도에 대비하고 실제 수질 개선을 위하여 본 연구의 결과를 바탕으로 수질관리를 위한 시스템의 보완 및 삭감계획의 수립에 관한 연구가 필요하다.알 수 있었다. 이상의 결과를 토대로 기존 압출추출방법과 초임계 추출 방법을 비교한 결과 $\gamma$-토코페롤의 농도가 1.3${\~}$1.6배 증가함을 확인할 수 있었다.게 상관성이 있어 앞으로 심도 있는 연구가 더욱 필요하다.qrt{F}}}{\pm}e_0$)에서 단정도실수 및 배정도실수의 역수 제곱근 계산에 필요한 평균 곱셈 횟수를 계산한다 이들 평균 곱셈 횟수를 종래 알고리즘과 비교하여 본 논문에서 제안한 알고리즘의 우수성을 증명한다. 본 논문에서 제안한 알고리즘은 오차가 일정한 값보다 작아질 때까지만 반복하므로 역수 제곱근 계산기의 성능을 높일 수 있다. 또한 최적의 근사 역수 제곱근 테이블을 구성할 수 있다. 본 논문의 연구 결과는 디지털 신호처리, 컴퓨터 그라픽스, 멀티미디어, 과학 기술 연산 등 부동소수점 계산기가 사용되는 분야에서 폭 넓게 사용될 수 있다.>16$\%$>0$\%$ 순으로 좋게 평가되었다. 결론적으로 감농축액의 첨가는 당과 탄닌성분을 함유함으로써 인절미의 노화를 지연시키고 저장성을 높이는데 효과가 있는 것으로 생각된다. 또한 인절미를 제조할 때 찹쌀가루에 8$\%$의 감농축액을 첨가하는 것이 감인절미의 색, 향, 단맛, 씹힘성이 적당하고 쓴맛과 떫은맛은 약하게 느끼면서 촉촉한 정도와 부드러운 정도는 강하게 느낄수 있어서 전반적인 기호도에서 가장 적절한 방법으로 사료된다.비위생 점수가 유의적으로 높은 점수를 나타내었다. 조리종사자의 위생지식 점수와 위생관리