• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.46-54
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• 2021

The seasonal and vertical biomass of marine forest seaweeds were examined to select a suitable species at 12 sites of the South Sea in Korea between 2018 and 2019. The Habitat Suitability Index (HSI) was also calculated in terms of biomass for six species (three kelp and three Sargassum species). A total of 16 marine forest-forming species including four kelp and 12 Sargassum species were observed at the 12 sites. The average annual seaweed biomass by season and depth ranged from 843.73-2,925.85 g wet wt. m^-2 at the eastern South Sea and from 343.87-4,580.10 g wet wt. m^-2 at the western South Sea. In the kelp species, the Ecklonia cava biomass was predominant, followed by E. stolonifera. The macroalgal species with the greatest biomass was Sargassum macrocarpum, followed by S. horneri. The HSI values of E. stolonifera were between 0.76-1.0 at eight sites and those of E. cava were 0.58-0.92 at four sites, indicating that E. stolonifera was more suitable than E. cava. In the HSI values of the Sargassum species, S. horneri ranged between 0.84-1.0 at all 12 sites and the S. macrocarpum values were between 0.68-0.99. The results indicate that E. cava and S. macrocarpum were the most suitable for the marine forest construction in terms of the seaweed biomass, and E. stolonifera and S. horneri in terms of the HSI values. Thus, we suggest that seaweed biomass and HSI values should be considered when choosing suitable forest-forming species.

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.166-174
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• 1993

Streptomyces coeUc%r (Muller) cells were treated with $100 \mu$M hydrogen peroxide for I hour and proteins synthesized during hydrogen peroxide stress were labeled with L-[$^{35}S$]-methionine. Total cellular proteins were extracted and analyzed by two-dimensional polyacrylamide gel electrophoresis. In exponential growth phase, synthesis of about 100 proteins was increased by hydrogen peroxide treatment. These proteins were named as Pin (£eroxide-inducib]e) proteins and classified into 4 subgroups according to their induction time after hydrogen peroxide treatment. About 60 of them were found to be induced within 20 minutes and maintained throughout I hour of treatment. In stationary growth phase. synthesis of 62 proteins was increased by hydrogen peroxide and 21 of them were the same Pins found in exponential growth phase. Proteins from the mutants which are resistant to hydrogen peroxide were obtained in exponential growth phase and compared with those from the wild type on two-dimensional gel. The three mutants, N7, N9. and N24, were found to have higher constitutive leve]s of ]5, 17, and 15 Pin proteins respectively, than the wild type. 9 of these Pin proteins (D74.7a, E76.0c, E23.3. F50.7, F47.2a. F25.5, G39.6b, G24.0, H39.6a) increased in two of the three mutants and 3 proteins (F39.7, H6I.7. 120.8) increased in all of the three mutants. These proteins might play important roles in the response of S. coelic%r to hydrogen peroxide.

• Journal of Power System Engineering
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• v.10 no.2
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• pp.75-82
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• 2006

세계적인 환경 보호 정책에 따라 할로겐화탄소 냉매를 대체할 환경 친화적인 초저온 냉매의 개발과 연구가 활발히 진행되고 있다. 일반적으로 캐스캐이드 2원 냉동 시스템에서 아직까지 할로겐화탄소 냉매가 널리 사용되고 있다. 탄화수소 화합물의 한 종류인 에탄은 낮은 지구 온난화 지수와 낮은 오존층 파괴지수를 가진 친 환경적인 자연 냉매이다. 본 연구는 지구 온난화 지수가 높은 R-23 냉매와 비교하여 캐스캐이드 2원 냉동 시스템에서 에탄의 성능 시험을 목적으로 수행 하였다. 1원측에는 R-22를 사용하였으며, 증발 온도에 따른 성능은 R-23 보다 에탄(R-170)이 더 높게 나타났다.

• Journal of Gifted/Talented Education
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• v.15 no.1
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• pp.67-84
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• 2005

In this study we investigated the adequacy of tools for distinction gifted students through the comparison these mutual relation on the basis of data, like paper test, the depths interview score, and the rest data((TTCT: Torrance Tests of Creative Thinking, IQ test, FASP: Find A Shape Puzzle, V.T: Visualization Tests and Exp: experimental ability test), and analysis data of EEG test for examining the adequacy of tools for identification gifted students. So, we developed Brain Wave gifted Index(G-Index) for finding another distinction ability as using brain waves data. The standard of index development use gifted brain characteristic in closed-eyes rest state which is judged like that characteristic of distinction between gifted and normal students is the most clear and consistence. That is, the degree of unified pattern between each object and gifted PCA pattern was defined by Pearson method which added spatial mutual index to weight concept. This refer to mean number of spatial PCA pattern. Searching for the possibility of distinction gifted gave distinction effect in 76%. The result of regression analysis on the basis of mutual relation between the rest data is . The probability formula for distinct gifted group is as follow. $$P=\frac 1{1+e^{-[-0.018(TTCT)+0.057(IQ)+1.916(FASP)+0.682(V.T)+0.088(Exp.)+0.034(G-Index)-57.510]}}$$ The result of this calculation showed that probability for distinct in gifted group was very good(95.0%). On the basis of upper result, tools for identification gifted students should be estimated as using many-sided estimation data whatever possible. And following study about development, and operation of tools for distinction suitable to gifted student in science should be progressed.

• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.239-243
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• 1985

The growth characteristics of Candida sp. JY-5 were examined on ethanol, acetic acid, or acetaldehyde as sole source of carbon by batch culture. The specific growth rates ($\mu$) of this strain on an ethanol during tile exponential period were changed depending upon the initial concentrations at above 0.5 g/l, but not in the proportion. The highest $\mu$ value was 0.291 hr$^{-1}$ and the maximum growth yield was 61.2％ at the concentration of 10 g/l. The $\mu$ values on an acetic acid substrate were constant regardless of the initial concentrations presenting 0.106 hr$^{-1}$ in the highest value. The maximum growth yield was shown as 46.8％ at the initial concentration of 10 g/l. The $\mu$ value on an acetaldehyde during the exponential period was 0.063 hr$^{-1}$ and the maximum growth yield was 44.9％ at the initial acetaldehyde concentration of 0.2 g/l.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.4
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• pp.367-375
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• 2016

In this study, the skin-improving effect was investigated through the oral intake of DuOligo (51.67% lactulose and 15.8% galactooligosaccharides). Thirty seven healthy women (40~60 in ages) were divided into placebo group (dextrin) and treatment group (DuOligo group), and each group was given a sample for oral intake for 8 weeks. After that, corneometer value, transepidermal water loss (TEWL), melanin index, erythema index, and wrinkle index were measured. As a result, moisture content of DuOligo group increased 38.22% than control group after 8 weeks significantly (p < 0.01). The TEWL of control group decreased by $3.39g/h/m^2$ after 8 weeks but the TEWL of DuOligo group decreased by $5.32g/h/m^2$ after 8 weeks. The melanin index of the control group was significantly increased with times, but the melanin index of the DuOligo group did not show any significant difference with times. The total wrinkles, length of total wrinkles, number of wrinkles, and depth of wrinkles significantly decreased (p < 0.05) compared to the control group. These results suggested that the applicability of DuOligo as a skin improving functional material was confirmed.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.326-331
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• 2018

Crop growth models are useful tools for understanding and integrating knowledge about crop growth. Models for predicting plant height, net photosynthesis rate, and plant growth of quinoa (Chenopodium quinoa Willd.) as a leafy vegetable in a closed-type plant factory system were developed using empirical model equations such as linear, quadratic, non-rectangular hyperbola, and expolinear equations. Plant growth and yield were measured at 5-day intervals after transplanting. Photosynthesis and growth curve models were calculated. Linear and curve relationships were obtained between plant heights and days after transplanting (DAT), however, accuracy of the equation to estimate plant height was linear equation. A non-rectangular hyperbola model was chosen as the response function of net photosynthesis. The light compensation point, light saturation point, and respiration rate were 29, 813 and $3.4{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. The shoot fresh weight showed a linear relationship with the shoot dry weight. The regression coefficient of the shoot dry weight was 0.75 ($R^2=0.921^{***}$). A non-linear regression was carried out to describe the increase in shoot dry weight of quinoa as a function of time using an expolinear equation. The crop growth rate and relative growth rate were $22.9g{\cdot}m^{-2}{\cdot}d^{-1}$ and $0.28g{\cdot}g^{-1}{\cdot}d^{-1}$, respectively. These models can accurately estimate plant height, net photosynthesis rate, shoot fresh weight, and shoot dry weight of quinoa.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.648-653
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• 2003

영벡터로 V(000)이 적용된 종전의 2상 RCD-PWM(Random Centered Distribution PWM)은 변조지수 M이 1에 가까울수록, 모터 전압 및 전류 스펙트럼의 광대역화 효과가 증가되지 않는 단점이 있다. 본 연구에서는 M에 따라서 영벡터를 선택하는 2상 MZRCD(Multi-Zero Vectors RCD)기법을 제안하였다. 2상 MZRCD기법은 M이 0.7보다 크게되면 영벡터로 V(111)을 선택하고, 작은 경우에는 V(000)을 선택하여, M의 전 영역에 걸쳐서 스펙트럼의 광대역화를 이룰 수 있는 방법이다. 본 연구의 타당성을 입증하기 위하여 Matlab simulink에 의하여 시뮬레이션을 수행하였다. M의 변화에 따른 모터 전압 및 전류의 스펙트럼을 검토하였으며, M과 무관하게 모터 전압 및 전류 스펙트럼이 광대역으로 선형화된 분포를 얻을 수 있었다.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.11-16
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• 1984

Rheological properties of waxy and non-waxy rice starch solutions were evaluated with a narrow gap rotational and Cannon Fenske viscometers. The gelatinized rice starch solutions containing 0.2-1.0% starch displayed pseudoplastic flow behavior. At higher starch level, degree of pseudoplasticity of waxy rice starch solutions increased, while that of non-waxy rice did not changed apparently. The consistency coefficient (K) of non-waxy rice starch solutions increased with increasing gelatinization temperature, but waxy rice starch solutions remained constant, and in alkaline aqueous solutions both of them showed increasing K values. The value of K increased exponentially with an increase in concentration. The effect of the temperature on the viscosity of the solutions followed Arrhenius' type equation, and the activation energies were in the range of 3.675-3.775 kcal/g-mol that were near to that of pure water. The changes of reduced viscosity with concentration were followed Huggin's equation and the values of intrinsic viscosity and interaction coefficient were 0.78-1.59 dl/g and 0.67-2.75, respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.538-544
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• 1996

A highly viscous biopolymer from alkali-tolerant Bacillus sp. was purified and its rheological properties were studied. 1% (w/v) solution of purified biopolymer showed pseudoplastic fluid behavior with the yield stress similar to those of xanthan and guar gum, and its consistency index was exponentially dependent on concentration and temperature. The concentration dependency of consistency index exhibited two rectilinear plots with different slopes at 1% concentration and pseudoplastic property increased with the increase of biopolymer concentration. The biopolymer solution exhibited a low temperature dependency and the activation energy of flow was 1.16 kacl/g mol. The apparent viscosity was very dependent on the change of pH and the addition of salt. However, no organic solvent effects were observed effects of viscosity synergism with the addition of viscosifier were not observed.