• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.9-15
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• 2016

We investigated >$50-{\mu}m$ marine planktonic organisms (mainly zooplankton) using a bongo net in Masan Bay and Jangmok Bay in order to harvest 75% of natural communities based on Phase-II approval regulations by the United States Coast Guard (USCG). The concentrated volume (in 1 ton) and abundance of zooplankton were $1.8{\times}10^7ind.ton^{-1}$ and $2.3{\times}10^7ind.ton^{-1}$, and their survival rates were 82.6% and 80.1%, respectively. The community structure in Jangmok Bay was similar to that in Masan Bay, and dominant species were adult and immature groups (stage IV) of genus Acartia. Harvested populations were inoculated in a 500-ton test tank. Although the population abundances were $6.0{\times}10^4ind.ton^{-1}$ for both bay samples, the mortality rates were higher in the Masan Bay population (32%) than the Jangmok Bay population (20%). We considered the reason to be that there were 30% more immature individuals of Acartia from Masan Bay than from Jangmok Bay. The younger population may have been greatly stressed by the moving process and netting gear. After applying a Ballast Water Treatment System (BWTS) using a sample form Jangmok Bay, the mortality rates in the treatment groups were found to be 100% after 0 days and 5 days, implying that the BWTS worked well. During the winter season, the zooplankton concentration method alone did not easily satisfy the approval standards of USCG Phase II (> $10{\times}10^4ind.ton^{-1}$ in the 500 ton tank). Increasing the netting frequency and additional fishing boats may be helpful in meeting the USCG Phase II biological criteria.

• ALGAE
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• v.25 no.3
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• pp.115-120
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• 2010

The natural growth of a population of Gomphosphaeria aponina Kutzing (Chroococcales, Cyanoprocaryota) was studied in a cemented freshwater tank in Allahabad, India. This population appeared to be a polymorphic species. Different species of the genus Gomphosphaeria have been segregated based on morphological features of colonies, cells and mucilage. However, these features are not well defined for different species. Our observations revealed many feature variations and, interestingly, certain features that have been described for different Gomphosphaeria species were seen in a single population. In this study, records of such variable morphological features were possible due to the availability of numerous specimens and continuous observations for more than two years. Further, this study revealed two points: (i) more detailed morphological studies are required both from nature as well as in culture to identify critical differences among the species, and (ii) molecular characterization of taxa appears to be necessary for final species settlement.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.66.4-67
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• 2016

Our recent investigation (Lee et al. 2015) suggests that the presence of double red clump in the Milky Way bulge is another manifestation of multiple populations observed in halo globular clusters. The origin of Helium enhancement in the 2nd generation population (G2), however, is not yet fully understood. Here we investigate the origin of this super-Helium-rich population in the framework of self-enrichment scenario. We find that chemical enrichments and pollutions by asymptotic giant branch stars and winds of massive rotating stars can naturally reproduce the observed Helium enhancement. The Helium to metal enrichment ratio appears to be ${\Delta}Y/{\Delta}Z=6$ for G2, while the standard ratio, ${\Delta}Y/{\Delta}Z=2$, is appropriate for G1, which is probably enriched mostly by typeII supernovae.

• Journal of the Korean Society of Safety
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• v.26 no.5
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• pp.105-109
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• 2011

Since a severe accident, which happens in low frequency, can cause serious damages, the interests in off-site consequence analysis for a nuclear power plant have been increased after Chernobyl, TMI and Fukushima accidents. Consequences, which are the effects on health and environment caused by released radioisotopes, are evaluated using MACCS II code based on the method of Level 3 PSA. To perform a consequence analysis for the reference plants, the input data of the code were generated such as meteorological data, population distribution, release fractions, and so on. Using these input data, acute and lifetime dose as an organ, CCDF for early fatalities and latent cancer fatalities, and average individual risk were analyzed by using MACCS II code in this study. These results might contribute to establishing accident management plan and quantitative health object.

• Kyungpook Mathematical Journal
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• v.60 no.2
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• pp.319-334
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• 2020

We propose a mathematical model with Holling type II functional response, to study the dynamics of vaccination. In order to make our model more realistic, we have incorporated the recruitment of infected individuals as a continuous process. We have assumed that vaccination cannot be perfect and there is always a possibility of re-infection. We have obtained the existence of a disease free and endemic equilibrium point, when the recruitment of infective is not considered and also obtained the existence of at least one endemic equilibrium point when recruitment of infective is considered. We have proved that if R_v < 1, disease free equilibrium is locally asymptotically stable, which leads to the elimination of the disease from the population. The persistence of the model has also been established. Numerical simulations have been done to establish the results obtained.

• Journal of Acupuncture Research
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• v.21 no.2
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• pp.103-113
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• 2004

Objective : This study was designed to investigate the relation between the angiotensin converting enzyme(ACE) gene polymorphism and Facial nerve palsy in the Korean population. Methods : This sudy was carried out on 117 Facial nerve palsy patients who were treated in the department of acupuncture & moxibustion, Hospital of Oriental medical college, Kyung-Hee University and 135 healthy control subjects. Blood samples from all subjects were obtaind for DNA extraction. The extracted DNA was amplified by polymerase chain reaction(PCR). PCR products were visualized by 2% agarose gel electrophoresis. Results : The sub-genotypes of ACE gene were II homozygotes, ID heterozygotes, DD homozygotes. While the distribution of ACE polymorphism in control subjects was 33%, 43%, 24%, the distribution of it in Facial nerve palsy patients was 32%, 50%, 18%(II, ID, DD). Thus, there was no significant different between the control and Facial nerve palsy groups. Conclusions : we conclude that there is no significant association between ACE gene polymorphism and Facial nerve palsy in Korean population. However, the findings of this study need to be confirmed in more patients and further studies. Additional epidemiologically based studies of the effects and relationship between ACE or other genes and lifestyles with regard to Facial nerve palsy is required.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.2
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• pp.50-58
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• 1998

Genetic Algorithm (GA) consists of selection, reproduction, crossover and mutation processes and many parameters including population size, generation number, the probability of crossover (Pc) and the probability of mutation (Pm). Determining values of the parameters is found critical in the whole optimization process and a sensitivity analysis with them seems mandatory. This paper tries to demonstrate such importance of sensitivity analysis of GA using an example water supply tunnel network of the New York City. For optimization of the network with GA, Pc and Pm vary from 0.5 to 0.9 by an increment of 0.1 and from 0.01 to 0.05 by an increment of 0.01, respectively, while fixing both the population size and the generation number to 100. This sensitivity analysis results in an optimum design of 22.3879 million dollars at the values of 0.8 and 0.01 for Pc and Pm, respectively. In addition, the probability of recombination (Pr) is introduced to check its applicability in the GA optimization of water distribution network. When Pr is 0.05 with the same values of Pc and Pm as above, the optimum design costs 20.9077 million dollars. This is lower than the cost of 22.3879 million dollars for the case of not using Pr by 6.6%. These results indicate that conducting a sensitivity analysis with parameter values and using Pr are useful in the optimization of WDN.

• Korean System Dynamics Review
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• v.7 no.2
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• pp.97-120
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• 2006

This paper deals with the extension of and discussion on the System Dynamics model (Jeong & Jeon, 2005) of river crabs in Korea. The previous model has been elaborated to empirically search for the optimal restoration and harvest rates of crabs in the Imjin River, on the basis of theoretical models of population dynamics in the field of bio-mathematics and environmental economics. In this paper, the authors tries to couple a series of new feedback loops related to density restrictions and cannibalistic behaviors with a stage-structured model of the crab ecosystem, and also to endogenize the parameter of baby crabs' survival that is caused by water quality improvement and income increase. Through these extensions and relaxations, the authors are able to argue about the strategic decision of the optimal rates additional considerations as well as the properties of the integrated system that was not covered in the previous paper.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.332-339
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• 2005

The effect of transinoculation of goat rumen liquor into sheep rumen on mimosine toxicity was studied. One adult Kutchi male goat having higher mimosine degradation capacity than sheep was gradually adapted to Leucaena leucocephala (Leucaena) leaves by feeding increasing level of eucaena leaves supplementation for 1 month. Six Bharat Merino rams (12-18 months of age) were divided into two equal groups with (group I) or without (group II) infusion of 200 ml of goat rumen liquor per animal. The mimosine degradation in groups I and II were 3.04 and 2.31; 3.90 and 3.73 mg per day per 10 ml rumen liquor respectively after 1 and 2 weeks of leucaena feeding leaves. Total rumen bacterial population in RGCA medium and in a selective medium containing iron showed an increasing trend in both groups, while the bacterial population growing in the presence of cellulose showed a decreasing trend. Animal performance data did not show any adverse effect. Results revealed that transinoculation of rumen liquor from leucaena leaves adapted goat to sheep rumen did not help to improve mimosine degradation in the sheep. The sheep transinoculated with goat rumen liquor displayed no in vivo improvements in nutrient utilization vis-a-vis mimosine metabolism.

• Journal of Ginseng Research
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• v.15 no.1
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• pp.31-35
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• 1991

In order to know the optimum planting density under shading structures at different light intensity, We investigated the growth status, distribution of ginseng leaf area, correlation between planting density and root weight per plant and yield, correlation between leaf area index and root weight per plant and yield. According to the increase of planting density the leaf area per plant was decreased, but leaf area index (L.A.I) was increased. Ginseng leaf population at different lines under common straw shading were distributed mainly in frost lines but polyethylene net shading at 10fo light intensity were distributed equally in all lines. Optimum planting density in common straw shading at 5% light intensity was 55 plant per tan (90 cmX180 cm) and polyethylene net shading 81 10% light intensity was 60 plant per tan, in consideration of root weight and yield. Optimum leaf area index was 2.4 under common straw shading at 5% light intensity but was 2.7 under polyethylene net shading at 10% light intensity.