• Journal of fish pathology
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• v.20 no.1
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• pp.41-47
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• 2007

To investigate the cause of the mass mortality during rockbream, Oplegnathus fasciatus seed production, the water quality and bacterial counts of sea water in breeding tanks was measured 20days post the hatch. During breeding of rockbream fry, the environmental factors of water quality were detected as pH, ammonia COD, phosphate at the supply of the food organisms and the seawater. pH was decreased from the 8.21 of the 1 day per hatch (dph) to 7.56 of the on the 7 dph. Ammonia was conversely increased 0.49 ppm of the 1 dph to 0.85 ppm of 10 dph. As the adding of the chlorella and the rotifer tanks, COD was increased the 3.3 times and 1.2 times than those of pre-adding respectively. The phosphate and the ammonia were also increased 1.7 and 2.3 times, with adding the chlorella respectively, which exceeded the second grade for sea water evaluation level, 0.015 ppm and 0.1 ppm respectively. Water quality was not improved by PSB (Photosynthetic Bacteria) treatment, which increased the value of COD in 1.7 times, phosphate in 2.7 times and ammonia in 1.4 times. The number of the bacteria was also increased along the dph. According to the treatment of chlorella, the number of total bacteria increased in 1.4 times and those of Vibrio sp. 1.6 times. The lethal concentration of ammonia was investigated that over than 10 ppm could killed the fry of rockbream within 28 hrs, but 40% in 2 ppm.

• Journal of Radiation Protection and Research
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• v.40 no.3
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• pp.162-167
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• 2015

Although the perfomance indicators of the nuclear power plants in Korea show optimal, it requires detailed analysis and discussion centered on the radiation dose. As analysis methods, analysis on the radiation dose of nuclear power plants over the past five years was assessed by comparing the relevant radiation dose of radiation workers and per capita average annual radiation dose of the world's major nuclear power stations was also analyzed. The radiation workers over the annual radiation dose limit of 50 mSv were not. The contrast ratio of the radiation exposure according to the reactor type was the normal operation of PHWR was 6.2% higher than those of the PWR. This shows the radiation work of PHWR during normal driving operation is much more than those of PWR. According to the Performance Indicators of the World Association of Nuclear Operator, the annual radiation dose per unit in 2013 showed 527 man-mSv of Korea is the best country among the major nuclear power generating states, the world average was 725 man-mSv. The annual per capita radiation dose is about 80% less than 1 mSv of the public dose limit and also the average per capita dose showed a very low level as 0.82 mSv. Workers in related organizations showed 1.07 mSv, the non-destructive inspection agency workers showed 3.87 mSv. The remarkable results were due to radiation reduced program such as development of radiation shielding and radiation protection. In conclusion, the radiation exposured dose of nuclear power plants workers in Korea showed a trend which is ideally reduced. But more are expected to be difficul and the psychological insecurity against the operation of the nuclear power plants is existed to the residents near the nuclear power plants. So the radiation dose reduction policy and radiation dose follow up study of nuclear power plants will be continously excuted.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.700-705
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• 2013

The purpose of this study is to investigate the quality changes and contamination of microorganisms such as Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in cherry tomatoes and head lettuces during the storage of different temperatures and periods. This study determines the pH levels, color changes and the growth patterns of microorganisms in cherry tomatoes and head lettuces during storage of 14 days at $5^{\circ}C$, $10^{\circ}C$ and $15^{\circ}C$. According to the results, the pH level is being reduced with storage periods in cherry tomatoes and head lettuces. The $L^*$, $a^*$ and $b^*$ values of cherry tomatoes are decreased with storage period, whereas the $a^*$ and $b^*$ values have increased with storage of the head lettuces. With regards to the types of microorganisms, the aerobic count plate (ACP), coliform count (CC), mold and yeast are being detected when cherry tomatoes and head lettuces are stored at $5^{\circ}C$, $10^{\circ}C$ and $15^{\circ}C$, whereas the S. aureus and E. coli are not being detected at 14 days of storage. The ACP, CC and yeast of cherry tomatoes increase with storage period, whereas the mold of cherry tomatoes was decreased after 14 days of storage. For the head lettuces, APC and CC have significantly increased with storage, whereas the mold stored at $5^{\circ}C$, $10^{\circ}C$ and $15^{\circ}C$ decreased after 21 days of storage. From these studies, we can confirm that changes in quality characteristics and the types of microorganisms existed in cherry tomatoes and head lettuces during storage were the ACP, CC, mold and yeast, whereas the E. coli and S. aureus are not detected.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.4
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• pp.67-80
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• 2015

Although recent policies and regulations in Korea strongly advocate and encourage cultivation of venture foundations, studies on venture foundation and success are very limited and often primarily focus on entrepreneurship or individual quality as a venture founder in addition to such studies' validity in question. Therefore, this study primarily focuses on venture preparation process which is subject to venture founder's effort to verify the policy effectiveness in the relationship between venture preparation and business performance. Major goal of this study is to reduce social cost of venture failure by suggesting systematic policy support for venture foundations and analyzing the relationship between following variables: first, venture preparation and financial performance, second, venture preparation and non-financial performance, and third, venture preparation and business performance. 400 initial venture foundations less than 5 years are selected from KISED(Korea Institute Startup & Entrepreneurship Development) trend analysis to carry out statistical analysis using SPSS 18.0. To organize the data features, frequency analysis as well as descriptive statistics are performed to verify the hypothesis. As a result, sub-factors in measurement of venture preparation which are venture education period, venture benefit, and experience of incubating organization are selected as independent variables. Likewise, sub-factors in measurement of business performance which are financial performance and non-financial performance are used as dependent variables. To validate interactive effect, venture preparation period is selected as control variable to perform hierarchical regression analysis. The analysis result verifies that venture benefit has positive influence on financial and non-financial performance while venture education period has positive influence on non-financial influence and experience of incubating organization has negative influence on non-financial performance without influence on financial performance. In addition, interaction of venture preparation period has positive influence solely between venture benefit and non-financial performance. Through this study, appropriate supporting plans depending on the level of venture preparation can be derived to improve business performance of initial venture foundations for policy designer of venture support, and quality rather than quality improvement of venture businesses is possible through investigation of structural issues of individual venture businesses. Ultimately, this study suggests venture founders to determine whether to focus on venture preparation process or to start a venture business.

• Environmental and Resource Economics Review
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• v.14 no.1
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• pp.167-199
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• 2005

The following policy implications can be drawn from this study: 1) The Air Pollution Emission Amount Report published by the Ministry of Environment since 1991 classifies industries into 4 sectors, i. e., heating, manufacturing, transportation and power generation. Currently, the usability of report is very low and extra efforts should be given to refine the current statistics and to improve the industrial classification. 2) Big pollution industries are as follows - s7, s17 and s20. The current air pollution control policy for these sectors compared to other sectors are found to be inefficient. This finding should be noted in the implementation of future air pollution policy. 3) s10 and s17 are found to be a big polluting industrial sector and its pollution reduction effect is also significant. 4) The effect of emission coefficient (${\Delta}f$) has the biggest impact on the reduction of emission amount change and the effect of economic growth coefficient (${\Delta}y$) has the biggest impact on the increase of emission volume. The effect of production technology factor (${\Delta}D$) and the effect of the change of the final demand structure (${\Delta}u$) are insignificant in terms of the change of emission volume. 5) Further studies on emission estimation techniques on each industry sector and the economic analysis are required to promote effective enforcement of the total volume control system of air pollutants, the differential management of pollution causing industrial sectors and the integration of environment and economy. 6) Korea's economic growth in 1990 is not pollution-driven in terms of the Barry Commoner's hypothesis, even though the overall industrial structure and the demand structure are not environmentally friendly. It indicates that environmental policies for the improvement of air quality depend mainly on the government initiatives and systematic national level consideration of industrial structures and the development of green technologies are not fully incorporated.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.625-634
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• 2004

The objective of this experiment is to study the possibility of lactate dehydrogenase(LDH) enzyme to prevent lactate accumulation in the rumen, For understanding capacity of bacterial LDH in rumen environments, this study was conducted to explore the effects of temperature, pH, VFAs and metal ions on Lactobacillus sp. FFy111-1's LDH activity, and the LDH activation in rumen fluid accumulated lactate. The optimum pH and temperature of LDH were pH 7.5 and 40$^{\circ}C$, respectively. The LDH activity had a good thennostability at range from 30 to 50$^{\circ}C$. The highest pH stability of the enzyme was at ranges from pH 7.0 to 8.0 and the enzyme activities showed above 64% level of non-treated one at pH 6.0 and 6.5. The LDH was inactivated by VFAs treatments but was enhanced by metal ion treatments without NaCl and $CuSO_4$ Especially, the LDH activity was increased to 127% and 124% of its original activity by 2 mM of $BaCl_2$ and $MnSO_4$, addition, respectively. When the acidic rumen fluid was treated by LDH enzyme of Lactobacillus sp. FFy111-1, the lactate concentration in the rumen fluid was lower compared with non-treated rumen fluid(P<0.05). This lactate reduction was resulted from an action of LDH. It was proved by result of purified D,L-LDH addition that showed the lowest lactate concentration among the treatments(P<0.05). Although further investigation of microbial LDH and ruminal lactate is needed, these findings suggest that the bacterial LDH has the potential capability to decrease the lactate accumulated in an acidic rumen fluid. Also, screening of super LDH producing bacteria and technical development for improving enzyme activity in rumen environment are essential keys for practical application.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.35-41
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• 2008

The purpose of this study was to investigate the effects of Chungkookjang viscous biopolymer supplementation on blood glucose and serum lipid-lowering in Streptozotocin (STZ)-induced diabetic rats. The rats were divided into three experimental groups; a normal group (N), diabetic control group (D), and a diabetic group with the supplementation of Chungkookjang viscous biopolymer (DCB). The groups were given experimental diets for four weeks. The normal group (C) was fed a casein-based diet, and the Chungkookjang viscous biopolymer group (DCB) received 3% biopolymer added to the casein-based diet. In the diabetic group (D), food intake increased significantly, but weight gain decreased significantly. The food efficiency ratio was significantly lower in the diabetic group. Liver weight increased significantly in the D group as compared to the N group. However, the DCB group showed a significant decrease in liver weight when compared to the D group. Blood glucose decreased significantly in the DCB group after receiving the experimental diet for four weeks, as compared to the diabetic control (p<0.05). Serum triglyceride levels were significantly lower in the DCB group than in the D group, whereas HDL-cholesterol levels were significantly higher (p<0.05). Total cholesterol was decreased in DCB group, but there were no significant differences. Also, LDL-cholesterol level was not significantly different among the experimental groups. Hepatic triglyceride and cholesterol were lower in the DCB group with no significant differences among groups. These results indicate that dietary supplementation of Chungkookjang viscous biopolymer improved glucose lowering and lipid metabolism in diabetic rats.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.1
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• pp.72-77
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• 1989

A study was conducted to obtain acid tolerant and superior Rhizobium meliloti strain for alfalfa on hilly acid soils. With host plant, eight isolates of R, meliloti selected in the vicinity of Milyang were evaluated for their ability to establish symbiotic effectiveness in acidified tube culture medium and vermiculite pot with different urea levels. Among isolates "YA03" was characterized for the ability to manifest to acid tolerance in three different soils of which pH were 5.0, 6.0, and 7.5. The results obtained were summarized as follows: 1. Of eight isolates "YA03" and "YA09" performed nodule in the tube medium of pH5.0, and in the symbiotic effectiveness YA03 was superior to others. 2. Alfalfa growth and $N_2-fixing$ activity by the inoculation of "YA03" isolate were better than others at the level of urea 1.25mM as well as nonurea. 3. Application of urea with inoculation of "YA03" islate to alfalfa was one of the effective factors for symbiotic effectiveness. 4. In infertile soil of pH5.0 inoculation of R. meliloti "YA03" to alfalfa caused the increase of shoot dry matter of 320% as compared to the control, and the total amount of yield was 131% as much yield in moderate fertile soil of pH7.5. Finally R. meliloti "YA03" isolate was selected as an acid tolerant strain.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.824-829
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• 2011

In recent years, there has been an increasing public concern about fecal contamination of water, air and agricultural produce by pathogens residing in organic fertilizers such as manure, compost and agricultural by-products. Efforts are now being made to control or eliminate the pathogen populations at on-farm level. Development of efficient on-farm strategies to mitigate the potential risk posed by the pathogens requires data about how the pathogens prevail in livestock manure composts and organic fertilizers. Microbiological analysis of livestock manure composts and organic fertilizers obtained from 32 and 28 companies, respectively, were conducted to determine the total aerobic bacteria count, coliforms, Escherichia coli count and the prevalence of Staphylococcus aureus, Bacillus cereus, Salmonella spp., Escherichia coli O157:H7, Listeria monocytogenes, and Cronobacter sakazakii. The total aerobic bacteria counts in the livestock manure composts and organic fertilizers were in the range of 7 to $9log\;CFU\;g^{-1}$ and 4 to $6log\;CFU\;g^{-1}$, respectively. In the livestock manure composts, coliforms and E. coli were detected in samples obtained from 4 and 2 companies, respectively, in the range of 2 to $5log\;CFU\;g^{-1}$ and $2log\;CFU\;g^{-1}$. In the organic fertilizers, coliforms and E. coli were detected in samples obtained from 4 and 1 companies, respectively, in the range of 1 to $3log\;CFU\;g^{-1}$ and $2log\;CFU\;g^{-1}$. In 3 out 32 compost samples, B. cereus was detected, while other pathogens were not detected. In 28 organic fertilizers, no pathogens were detected. The complete composting process can result in the elimination of pathogens in livestock manure compost and organic fertilizer. The results of this study could help to formulate microbiological guidelines for the use of compost in environmental-friendly agriculture. This research provides information regarding microbiological quality of livestock manure compost and organic fertilizer.

• Journal of Conservation Science
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• v.34 no.6
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• pp.595-604
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• 2018

In this study, in a bid to develop natural bioadhesives for paper craft, the hanji industry, and preserving cultural assets, complex polysaccharides were extracted from brown and red algae and used as an ingredient in adhesives. Brown algae include sea trumpet, kelp, sea oak, and sea mustard, whereas red algae include Pachymeniopsis elliptica agar-agar weed, Gloiopeltis tenax, and hunori. The polysaccharides were extracted after transforming them from non-aqueous Ca complexes contained in each of the brown and red algae into water-soluble polysaccharides containing alkali metals with a solubility level of 1. and extracted Subsequently, only the polysaccharides were extracted using alcohol precipitation. The adhesion tensile strengths of kelp, a brown algae, and Pachymeniopsis elliptica, a red algae, were 21.58 and 32.99 kgf, respectively. They thus demonstrated better adhesion than that of solid glue products such as water plants (18.45 kgf) and glue sticks (20.45 kgf). The extraction yield of these polysaccharides is supposed to be determined according to their extracted environments; however, no difference in adhesion strength was seen. Further, it was found that the shapes of polysaccharides were determined by their growing environment instead of extraction environment. Use of multi-step alcohol precipitation method during extraction enabled the removal of the constituents except protein and other polysaccharides, thereby demonstrating a stable outcome without cultivation of mold. Furthermore, there was no occurrence of mold even after production of the adhesives by the simple solution method, which demonstrates the adhesive's potential as an environment-friendly adhesive material.