• Journal of the East Asian Society of Dietary Life
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• v.3 no.2
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• pp.107-119
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• 1993

The objeative of this study was to investigate the possibility of estimation of internal quality by observing visible state of strawberry. Several tests such as color("L", "A", H,V,C), degree of blackred ness, opening state of calyx, vitamin C content, brix degree, acidity, freshness, overall quality, chlorophyll content, and anthocyanin content were performend during circulation at 20$^{\circ}C$. Acidity(R=-0.96), chloroph-yll content(r=-0.99), vitamin C content(r=-0.98), freshness(r=-0.96), and overall quality(-0.99), degree of blackredness(r=0.98) and opening state of calyx(=0.98), color saturation(r=0.99), degree of blackredness(r=0.98) and opening state of calyx(=0.98) increased during circulation at 20$^{\circ}C$. in correlation between visible indicators andd internal qualities, "L" valu and brix degree was r=-0.74, "a" and brix degree was r=0.93 Hue and anthocyanin content was r=0.74, value and chlorophyll content, brix degree were r=-0.91, r=-0.77, chroma and brix degree was r=0.96. The correlations between color saturation and vitamin C content(r=-0.96), chlorophyll content(r=-0.98), freshness(r=-0.98), overall quality(r=-0.94), loss of total polyphenol(0.94) and acidity(r=-0.94) showed high correlation. The correlatiions between degree of blackrednes and vitamin C content(r=-0.99), chlorophyll content(r=-0.94), anthocyanin content(=-0.74), freshness(r=-0.97) overall quality (r=-0.95), loss of total polyphenol(r=0.93) and acidity(r=-0.91) chlorophyll content(r=-0.99), freshness(r=-0.98), overall quality(r=-0.92), loss of total polyphenol(r=0.99) and acidity(r=0.83) showed high correlation.

• Journal of the korean society of oceanography
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• v.37 no.1
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• pp.35-44
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• 2002

To assess the relative contribution of bacterial and phytoplankton biomasses to particulate organic matter (POM) in the water column, microbial abundance and biomass were from two transects in the western channel of the Korea Strait in 1996. Bacterial abundance had a mean value of $5.9{\times}10^5$ cells/ml and chlorophyll-a averaged 0.14 ${\mu}g/l$. Bacterial abundance in the Korea Strait showed a positive relationship with chlorophyll-a concentration, while the distribution of POM did not covary with chlorophyll-a. Particulate organic carbon (POC) and nitrogen (PON) concentrations were greater in August than in October. Bacterial carbon (POC) and nitrogen (PON) concentrations were greater in August than in October. Bacterial carbon and nitrogen biomasses were 7.29 ${\mu}gC/l$ and 1.24 ${\mu}gN/l$, respectively, during the study periods. Bacterial biomass was larger in October than in August due to the autumn phytoplankton bloom. Phytoplankton biomass based on chlorophyll-a was 7.67 ${\mu}gC/l$ for carbon and 1.10${\mu}gN/l$l for nitrogen. The ratio of bacterial carbon (BC) to phytoplankton carbon (Cp) averaged 0.95 in the Korea Strait in 1996. Bacteria may play a more significant role in the dynamics of POM than phytoplankton do in August, with BC/Cp ratio of 1.26. The ratio of BC to Cp increased with a decrease in chlorophyll-a concentration. Averaged over all the samples in both cruises, the contribution of microbial biomass to POC and PON was about 43% and 51%, respectively. Bacterial assemblage constituted a significant fraction of POC (21%) and PON (27%). Phytoplankton accounted for 22% of POC and 24% of PON. Microbial biomass played a more important role in the dynamics of POC and PON in October than in August due to a significant increase in microbial biomass in the southern transect (transect-B) in October by the autumn phytoplankton bloom. This study showed that marine microbes may constitute a significant part in the reservoir of POM in the Korea Strait.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.95-100
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• 1998

The purpose of this study is to describe the change of the spring bloom and oceanographic condition. The variation of pigment concentration derived from the satellite ocean color data has been analyzed. According to the movement of blooming area, blooming was very concerned with a rising trend of sea surface temperature and a supply of nutrients. A nutrient rich water carried by the Oyashio encounters with the warm Core ring, where mixings and blooms are observed. We examined the correlation by using the satellite observations of the temperature and chlorophyll-a for the spring seasons (May, June, July) of 1998 the off Sanriku area (38-43N, 141- l50E). Using the SeaWiFS data, we process the data into the level-3, which contains the geophysical value of chlorophyll-a. And chlorophyll-a data is mapped for the water between 110E and 160E, and 15N and 52N with a 0.08 * 0.05 degree grid for each image. And Sea Surface Temperature (SST) data is produced using the AVHRR onboard the NOAA. The SST is derived by the MCSST. Then, the data is mapped for the water as much as chi-a data. And these gridded image was made by detection of each water masses, which are Kuroshio Extension, the warm-core ring and the Oyashlo Intrusion, etc., using those satellite images to determine short term change. Off Sanriku is a place where warm-water pool and the Oyashio at-e mixed. When warm streamer has intruded in cold water, the volume of phytoplankton increases at the tip of warm streamer. Warm water streamer was trigger of occurring blooming. And also, SeaWiFS images provided as much information for the studies of chlorophyll-a concentrations in the surface.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.2
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• pp.109-114
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• 2001

A CAB cDNA vector(pKGCAB), encoding the light harvesting chlorophyll a/b binding protein in Korean ginseng (Panax ginseng C. A. Meyer), was constructed with the CaMV35S promoter of plant expression vector. The chimeric vector was transformed into tobacco(Nicotiana tabacum cv. NC 82) using Agrobacterium tumefaciens LBA 4404 strain, and the transgenic tobacco plant CAB-TP2 was selected. Photosynthetic rates of the CAB-TP2 plant at before-flowering stage were increased about 20% under low irradiance conditions of quantum 100 and 500 $\mu$mol.m$^{-2}$ s$^{-1}$ , however, the rates were similar to those of NC 82 under quantum 1000 and 2000 $\mu$mol.m$^{-2}$ s$^{-1}$ conditions. The plants were germinating under low- or normal irradiance condition and the quantum yield of photosystem III were measured. The differences of the Fv/Em values between conditions were 0.07 and 0.01 in NC 82 and CAB-TP2, respectively. The mature leaves in the position 8-10 of the CAB-TP2 at before-flowering stage revealed l0% higher Fv/Fm values in range of 0.759 to 0.781 and 40% more chlorophyll contents of 70-93mg/$m\ell$ than those of normal NC 82. These data suggest the possibility that the increase in photosynthetic activity of leaves under low light intensity in the canopy of CAB-TP2 transgenic tobacco might lead to increase the quality of lower tobacco leaves.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.140-143
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• 2003

This study was performed to develop a more rapid and simple nutrient diagnosis method of plants than the conventional leaf analysis method. tomato (Lycopersicon esculentum Mill. cv. super momotaro) was planted in the mixed media produced by mixing perlite and rock wool at 1 . 1 (v/v) ratio. The Yamazakki nutrient solutions for cucumber and tomato were supplied to the media using the micro-drip irrigation system. Experimental plots produced consisted of no fertilization, deficient fertilization, adequate fertilization and surplus fertilization for N, P and K, respectively. Each experimental plot was replicated four times. Specific color different sensor values (SCDSV) measured by the chlorophyll meter were closely related to total-N concentrations in the leaves measured by the conventional method. Nitrate, $PO_4$ and K concentrations in petiole sap measured by test strips #(Reflectoquant^{\circledR},\;Merck,\;Germany)$ showed a significant relationship with total-N, p and K concentrations in leaves. The linear regression equations between $NO_3,\;PO_4$ and K concentrations in petiole sap and total-N, p and K concentrations in the leaves were prepared. The optimum levels of $NO_3,\;PO_4$ and K in petiole sap were obtained by plugging the optimum concentrations of total-N, p and K in the leaves by other researchers into the equations. In conclusion, the SCDSV by the chlorophyll meter and concentrations of NO3, p and K in petiole sap measured by the test strips would be suitable for rapid estimation of plant nutrient status.

• Journal of Korean Society on Water Environment
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• v.29 no.6
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• pp.832-841
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• 2013

In recent years, eutrophication in the Paldang Lake has become one of the major environmental problems in Korea as it may threaten drinking water safety and human health. Thus it is important to understand the phenomena and predict the time and magnitude of algal blooms for applying adequate algal reduction measures. This study performed seasonal water quality assessment and chlorophyll-a prediction using Bayseian simple/multiple linear regression analysis. Bayseian regression analysis could be a useful tool to overcome limitations of conventional regression analysis. Also it can consider uncertainty in prediction by using posterior distribution. Generally, chlorophyll-a of a P2(Paldang Dam 2) site showed high concentration in spring and it was similar to that of P4(Paldang Dam 4) site. For the development of Bayseian model, we performed seasonal correlation. As a result, chlorophyll-a of a P2 site had a high correlation with P5(Paldang Dam 5) site in spring (r = 0.786, p<0.05) and with P4 in winter (r = 0.843, p<0.05). Based on the DIC (Deviance Information Criterion) value, critical explanatory variables of the best fitting Bayesian linear regression model were selected as a $PO_4-P$ (P2), Chlorophyll-a (P5) in spring, $NH_3-N$ (P2), Chlorophyll-a (P4), $NH_3-N$ (P4) in summer, DTP (P2), outflow (P2), TP (P3), TP (P4) fall, COD (P2), Chl-a (P4) and COD (P4) in winter. The results of chlorophyll-a prediction showed relatively high $R^2$ and low RMSE values in summer and winter.

• Journal of Environmental Science International
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• v.22 no.11
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• pp.1499-1508
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• 2013

In the results of investigating the role of LED light quality in enhancing the ornamental value of indoor foliage plants, amber and red light increased plant height, leaf width, and leaf stalk, and the consequent tree shape decreased the ornamental value. The chlorophyll content increased significantly under white light and compound light. With regard to the effect of plant leaf color on ornamental value, the value of lightness was markedly enhanced by red light. As to the functionality of plants according to photosynthetic activity, plants such as Dieffenbachia, Clusia, and Dracaena were found favorable to those staying indoors for a longtime from morning to evening. Spathiphyllum, and Ficus were found to be recommendable for indoor spaces used actively during afternoon because their photosynthesis was activated in the afternoon. With regard to power consumption according to light quality, white light consumed 119 W/hour, around 45% lower than that of fluorescent lamps, so it is considered the optimal artificial light quality that can enhance energy efficiency. Red light consumed 72 W/hour, only 33% of that of fluorescent lamps, but it was not considered the optimal light quality because plant growth was poor under the light quality. White light and compound light were found to be the ideal light sources for improving the functionality and ornamental value of indoor plants and reducing the cost of maintenance, but because compound light hinders people from recognizing the original color of plants and makes their eyes easily tired, white light was considered the optimal light satisfying all of the ornamental value, economic efficiency and functionality resulting from plant growth.

• Journal of Korean Society of Water and Wastewater
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• v.34 no.4
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• pp.277-288
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• 2020

In this study, we performed algorithms to predict algae of Chlorophyll-a (Chl-a). Water quality and quantity data of the middle Nakdong River area were used. At first, the correlation analysis between Chl-a and water quality and quantity data was studied. We extracted ten factors of high importance for water quality and quantity data about the two weirs. Algorithms predicted how ten factors affected Chl-a occurrence. We performed algorithms about decision tree, random forest, elastic net, gradient boosting with Python. The root mean square error (RMSE) value was used to evaluate excellent algorithms. The gradient boosting showed 10.55 of RMSE value for the Gangjeonggoryeong (GG) site and 11.43 of RMSE value for the Dalsung (DS) site. The gradient boosting algorithm showed excellent results for GG and DS sites. Prediction value for the four algorithms was also evaluated through the Receiver operating characteristic (ROC) curve and Area under curve (AUC). As a result of the evaluation, the AUC value was 0.877 at GG site and the AUC value was 0.951 at DS site. So the algorithm's ability to interpret seemed to be excellent.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.759-765
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• 1997

The process of the senescence in Oryza glaberrima Steud. strains and Oryza sativa L. cultivars were examined in terms of SPAD value(chlorophyll content) and photosynthetic rate. SPAD values and photosynthetic rates of flag leaves for 10 genotypes of each species was measured at the 1, 3 and 5 weeks after heading. SPAD values and photosynthetic rates of O. glaberrima strains tended to decrease rapidly after heading. O. sativa cultivars showed slower decrease as compared to O. glaberrima strains, in particular during the period from 1 to 3 weeks after heading. Although there was no significant difference between the two species in the mean value of photosynthetic rate and SPAD value at 1 weeks after heading, O. glaberrima had lower values after 3 weeks after heading. There were significant positive correlation coefficients between the photosynthetic rate and the SPAD value at 1 and 3 weeks after heading for O. glaberrima strains, and at 1 and 5 weeks after heading for O. sativa cultivars. There were significant positive correlation between the decreasing rates of the photosynthetic rates and the decreasing rates of the SPAD values at the period from the 1 to 3 weeks after heading for both species. At the period from 3 to 5 weeks after heading, only O. glaberrima showed a significant correlation between two traits, indicating that rapid decrease in chlorophyll content would affect the photosynthesis in O. glaberrima.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.357-367
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• 2007

Recently, eutrophication or lake and reservoir has become serious problem to man who want use that water for several purpose. In order to solve the eutrophication problem, the trophic state of that eutrophic lake and reservoir should be measured properly. For the purpose of this, various method to indicate the trophic state of lake and reservoir was developed by many researchers. This research was conducted to evaluate characteristics and eutrophication of water qualitymfor small scale reservoir in Kunsan. On-site investigation to 5 reservoirs and laboratory experiment were carried out during four seasons from November, 2003 to July, 2004. Twelve items measured field ana a laboratory. Measured data was analyzed to quantitative method by multivariate approach and eutrophication index. The result is summarized as following. 1) Showing the characteristics of water quality for reservoir in Kunsan, Okgu reservoir and Oknua reservoir was exceeded 4 grades of agricultural water standard in TP, TN and COD. This means that eutrophication was gone much, therefore, water-purity control of reservoir need. While, Mije reservoir that is used to Kunsan citizens' recreation was good in water quality. But, water quality exceeded 4 grades of agricultural Dater standard sometimes. 2) As a results of correlation analysis between variables of water qualify, Interrelation between variables which is connected with eutrophication was expressed good relationship as above 6.000 in correlation coefficients. The correlation coefficient(r) between COD and chlorophyll-a, total phosphorus and chlorophyll-a, total nitrogen and chlorophyll-a were 0.750, 0.720 and 0.600 respectively. Therefore, Change of water quality can grasp according to eutrophication progress degree. 3) If do evaluate to eutrophication by quantitative method which is proposed by OECD, US-EPA and Forsberg & Ryding, in the case of chlorophyll a, Okgu, Oknua and Daewi reservoir was eutrophic state and Mije and Geumgul reservoir was mesotrophic state. But, estimation by TN and TP showed highly eutrophic state (hypereutrophic) in all reservoirs. 4) If do evaluate by eutrophication index which is Carlson's TSI, revised carlson TSI and Walker's index, in the case of chlorophyll a, TSI values of Okgu, Oknua and Daewi reservoir is eutrophic state more than 50 and Mije and Geumgul reservoir was mesotrophic state as range of $40{\sim}50$ in TSI value. But, in the case of TP as nutrients, all reservoirs showed highly eutrophic state which was exceed to 70 in TSI value. According to above results, the water quality for small scale reservoirs in Kunsan is progressing by trophic state. therefore, for continuous use as agriculture water, we had better do establishment of management plan about water quality.