• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.7
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• pp.1066-1071
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• 2017

Recently high voltage impulse (HVI) technique has been extensively studied for desalting processes to control the $CaCO_3$ scale formation in industrial water practices such as power plant, boiler, and heat exchange operations. Investigation of the operational parameters for the HVI is important, however, those had not been reported yet. In this study, the effect of initial feed volume and contact time on reduction of calcium ion concentration by the HVI technique was investigated. Initial feed volumes of artificial hard water which contained 100 mg/L of $Ca^{2+}$, were set to 1, 2, and 3 L respectively. After 24hr of HVI contact with 12kV, $Ca^{2+}$ ion was reduced to 50, 29 and 19 % of their initial concentration, indicating that calcium removal increased as initial feed volume decreased. This implies the applied HVI pulse energy per unit mass of calcium is important parameter determining overall desalting efficiency. A series of extended operations of HVI up to 30 days verified the long term stability of the HVI system. The calcium ion declined to 40 mg/L after 2~3 days, and further reduction of calcium was not achieved, indicating that optimum operation time could be 2~3 days under these experimental conditions. Consequently, it was confirmed that the important operational parameter of HVI technique is initial feed volume and contact time as well as the applied voltage that was already proven in the previous study.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.1
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• pp.78-84
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• 1998

The fluid system such as, the quantity control of raw water, chemicals control in the purification, the waste water system as well as in the feed water or circulation system of the power plant and the ventilation system is controlled with the valve and moter pump. The system's performance and the energy saving of the fluid systems depend on control of method and delicacy. Until, PI controller use in these system but it cannot control delicately because of the coupling in the system loop. In this paper we configure a single flow system to the multi variable system and suggest the application of 2-DOF PID controller and the tuning methods by the neural network to the electrical power of the flow control system. the 2-DOF controller follows to a setpoint has a robustness against the disturbance in the results of simulation. Keywords Title, Intelligent control, Neuro control, Flow control, 2 - DOF control., 2 - DOF control.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.1
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• pp.13-26
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• 1988

^x This study was executed to analyze the vegetational landscape structure of Donggu Royal Tomb forest by four kinds of ordination techniques(polar, principal component analysis, reciprocal averaging, and detrended correspondence analysis) and comparison of the couple photographs between 1920s and 1987. Thirteen sites were sampled with clumped sampling method in June of 1987 and five quadrats were examined in each site. The result of this study can be summarized as follows. 1. Environmental impact grade 3,4 and 5 area covered 16.11ha and these area should be restored by the input of human energy because self - refair seemed to be impossible. 2. Pinus densiflora community of actual vegetation covered 8.2%, Alnus japonica community 5.7% and quercus aliena community 15.8% of the surveyed area(73.3ha). And afforested vegetation including Pinus koraiensis, Pinus rigida, Alnus hirsuta and Robinia pseudoacacia covered 27.0%. 3. Donggu Royal Tomb forest was divided by Pinus densiflora, P. densiflora-Quercus aliena, Alnus japonia - Q. aliena and A. japonica community. DCA was the most effective method of this study. 4. DCA ordination were showed that succesional trends of tree species seem to be from Pinus densiflora through Prunus sargentii, Quercus serrata, Quercus aliena to Carpinus laxiflora in P. densiflora community and from Alnus japonica through Acer ginnala to Q. aliena in A. japonica community of the upper layer and from Rosa multiflora, Symplocos chinensis for. pilosa, Zanthoxylum schiniflolium through Rhus trichocarpa, Styrax japonica, Rhododendron scilippenbachii to Viburum erosum, Lindera obtusiloba in the middle layer. 5. By the comparsion of the couple photographs beween 1920s and 1987, we can recognize the change of historical landscape composed by P. densiflora and A. japonica community and those community is succeed to Q. aliena.

• Journal of Conservation Science
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• v.34 no.1
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• pp.51-57
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• 2018

Herein, we present the results of the analysis of a lacquer coating fragment excavated from 'Daesungdong No.88 tomb of Gimhae'. We observed the fragment with an optical microscope and used scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) as well as Fourier-transform infrared spectroscopy analysis to determine the structure of the lacquer coating and the technique used for coating. The sample was identified as a Moksim Jophy Lacquer. It is made from wood, painted with textile fabric and coated with soil clay. The SEM-EDS analysis revealed residues of bone meal at the bottom part of the sheath layer. The incorporation of bone meal in a lacquer coating layer is one of the characteristics of the Han Dynasty, and was also found in the Nangnang Region and the United Silla Dynasty. Inside the sword sheath is a specific adherent structure of silk fabric, the same type of leguminous plant found in another sword sheath excavated from the Eastern Han-tomb of Xi'an. Results constitute the latest information about lacquer ware found in the southern district of the Korean peninsula. Moreover, the findings shed light on an international relationship with Kumkwan-Kaya where the sword sheath was produced.

• Journal of Crop Science and Biotechnology
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• v.10 no.2
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• pp.112-116
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• 2007

Kinetin(KN) is an inducer of rice(Oryza sativa L.) defense/stress responses, as evidenced by the induction of inducible secondary metabolite and defense/stress protein markers in leaf. We show a novel light-dependent effect of KN-triggered defense stress responses in rice leaf. Leaf segments treated with KN(100 ${\mu}M$) show hypersensitive-like necrotic lesion formation only under continuous light illumination. Potent accumulation of two phytoalexins, sakuranetin and momilactone A(MoA) by KN that peaks at 48 h after treatment under continuous light is completely suppressed by incubation under continuous dark. Using two-dimensional gel electrophoresis we identified KN-induced changes in ribulose-1, 5-bisphosphate carboxylase/oxygenase, energy- and pathogenesis-related proteins(OsPR class 5 and 10 members) by N-terminal amino acid sequencing and mass spectrometry. These changes were light-inducible and could not be observed in the dark(and control). Present results provide a new dimension(light modulation/regulation) to our finding that KN has a potential role in the rice plant self-defense mechanism.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.716-721
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• 1999

It has been known that continuous cultivation of hairy root is difficult to maintain for a long period of time compared to the microbial and callus cultures. Chemostat cultivation was successfully carried out in order to economically produce a plant-based colorant, betacyanin, from red beet hairy root for more than 85 days in a 14-1 fermentor. The result from the chemostat cultivation was compared to those of the batch and fed-batch cultivations of red beet hairy roots. It was shown that hairy root reached its steady state within 50 days of the cultivation, and then maintained for about 25-30 days in a wide range of dilution rates. Total betacyanin production from the continuous process was also calculated to be 2.65g at 0.28(l/d) of dilution rate, compared to 0.196g from fed-batch cultivation. It was found that betacyanin production was a partially growth related process, yielding 0.376 mg/g-fresh wt. cell and $1.89{\times}10^{-5}$ mg/g-fresh wt. cell/d, with 0.92 of correlation factor in a partial growth-product model. It was also shown that the cell growth required was relatively large for maintenance amount of energy at a low dilution rate. The growth of hairy root was inhibited by high light intensity in following a photo-inhibition model. The growth parameters were estimated to be 0.3(l/d), $10.56kcal/\textrm{m}^2/h$,{\;}and{\;}35.81kcal/\textrm{m}^2/h$ for the maximum specific growth rate, half saturation light intensity, and inhibition light intensity, respectively.

• Applied Biological Chemistry
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• v.11
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• pp.167-171
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• 1969

Gartic bulblets were planted to investigate the effect of some different cultivating conditions on the growth and bulb formation of the garlic plants (Allium sativum L.) Two different conditions namely perfect and imperect aerobic condition, and 3 different fertilizer levels was made. The split plot design was adopted for this experiment. 1) For the growth rate, under the imperfect aerobic condition, the plant height was more increased than that of perfect aerobic condition no relation to the fertilizer levels. 2) With respect to the fresh weight of garlic, the similar tendency to the growth rate was observed, but dry weight was did not. 3) The uptake of phosphorus was found to be increased in the imperfect condition. It could there be concluded that imperfect aerobic condition seems to be much favorable condition than the perfect aerobic condition to the development of garlic bulbs.

• Korean Institute of Interior Design Journal
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• v.19 no.1
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• pp.46-54
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• 2010

Since the accomplishment of industrialization and mechanization, human and the nature have gone farther their own way. Human depending on technology have been increasingly expanding and developing their artificial space and as times go by in such a way, estrangement between the human and nature has resulted in dissatisfaction of human's instinctual desire and devastation of human's living. People, to deal with such challenge, begins taking a look at the nature. In introducing the nature into the modern architecture, a physical natural element is often directly taken into or the shape that could be inferred from the nature is taken. The study was intended to identify the characteristics of the pattern introducing the nature into the modern architecture, as mentioned in the former case, which is summarized as follows, Introduction of the nature contains a variety of functions in the space and it creates the new space by integrating the internal and external space which becomes boundaryless integrated space. The boundary in the building tends to be getting more ambiguous, while the space accommodating the nature serves the interface, playing a role of intermediator for both the internal and external space. It functions the open public place that helps build the natural community among the users but taking the nature into the inner space, and it is used to attempt to change the interior of the building or for ventilation lighting or energy-saving purpose. The spatial meaning was found to have varied depending on pattern of the nature introduced. Such conclusions mentioned hereon is expected to help forecast and understand the forthcoming space accommodating the nature when reviewing the pattern of introducing the nature appeared In modern architecture.

• Journal of radiological science and technology
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• v.28 no.2
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• pp.117-122
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• 2005

According to the Para. 5 of Art 2 of the Korean Nuclear Safety Regulations, which was revised in 1999, internal dose assessment as well as external one should be performed by law for employees at a nuclear power plant from 2003, and their estimate errors should also be within 50%. Thus, more accurate internal dosimetry becomes important. Corresponding to such regulation revision, we are developing a more accurate thyroid-uptake internal dosimetric system and have developed a Monte Carlo simulation code, the so-called CALEFF, to calculate the detection efficiency of the dosimetric system. In this paper, we calculated detection efficiencies with various test conditions by using the CALEFF code and discussed their characteristics. We may use the detection efficiency calculated by the code in calibrating the thyroid internal dose from measured data.

• Nuclear Engineering and Technology
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• v.21 no.1
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• pp.1-11
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• 1989

Numerous losses of decay heat removal capability have occurred at U during stutodwn while its significance to safety is needless to say. A study is carried out as an attempt to assess what could be done to lower the frequency of these events and to mitigate their consequences in the unlikely event that one occurs. The shutdown risk model is developed and analyzed using Event/Fault Tree for the typical pressurized water reactor. The human cognitive reliability (HCR) model, two-stage bayesian approach and staircase function model are used to estimate human reliability, initiating event frequency and offsite power non-recovery probability given loss of offsite power, respectively. The results of this study indicate that the risk of a Pm at shutdown is not much lower than the risk when the plant is operating. By examining the dominant accident sequences obtained, several design deficiencies are identified and it is found that some proposed changes lead to significant reduction in core damage frequency due to loss of cooling events.