• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.156-161
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• 2006

Overhead and sub-irrigation of deep sea water to tomato seedlings reduced the height as 50% and 58% than control plants. In the same treatment with surface sea water and NaCl water, the reduced rate in tomato seedlings' height were 49% and 56% in overhead irrigation, and 47% and 57% in sub-irrigation, respectively. Most effective method for the inhibition of the growth of the seedling was sub-irrigation method, which supplied water through the roots. No significant difference was observed on fresh weight of the upper part of tomato and cucumber seedlings, though the sub-irrigation reduced the fresh weight than the overhead irrigation. The reduced rate of fresh weight of seedlings by overhead irrigation was by 38% and sub-irrigation by 49% as compared to control. Similarly dry weight of upper and under soil parts of seedlings showed same trend of results thereof as fresh weight. This result can be traced to reduction of growth caused by salts in the water. In stem diameter of seedlings no significant difference was observed between two irrigation methods, even though both deep sea and NaCl water reduced stem diameter, as compared to control water. Overhead irrigation can be chosen by seedling producers because of better seedling quality by using TH ratio. Seedling compactness were not noticed in both the overhead and sub-irrigation. Sub-irrigation was found more effective method far the inhibition of height and compactness of tomato seedlings. Higher the concentration of NaCl, deep sea, and surface sea water, lesser the growth in height, fresh and dry weight, stem diameter, and leaf area was obtained. No significant difference was found, though sub-irrigation suppress the growth of seedlings.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.594-602
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• 2022

The study aim was to analyze the effects of slurry composting and biofiltration (SCB) liquid fertilization on the early growth of Chamaecyparis obtusa. Control, chemical fertilizer (CF), low liquid fertilizer (LLF), and high liquid fertilizer (HLF) sites with five trees per site were established, and each treatment was repeated three times. The growth analysis showed that HLF-200 (treated with HLF 200%) had the highest growth. To assess the fertilization effect, root-collar diameter and height growth models were developed for the HLF-200 and control groups. We found that the Schumacher anamorphic and Schumacher polymorphic equations were best suited for the root-collar diameter growth models in the control and HLF-200 groups, respectively. For the height growth models, the Gompertz polymorphic equation was the most appropriate. From the growth curve generated by the chosen model, the effect of fertilization on the amount and rate of the root-collar diameter and height growth were higher in the HLF-200 group than in the control group. Treatment with SCB liquid fertilization was judged to be suitable for the early growth stage of Chamaecyparis obtusa.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.1-4
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• 2006

Closing processes of taping holes and diameter growth of taped trees of Acer mono were investigated to understand the effects of sap taping and number of tapping holes on tree growth and closing speed of holes. Closing processes of tapping holes were faster at trees taped of ten holes than trees tapped of one, three, five holes during the study period, and tapped holes were completely filed up within 15 months. Diameter growth by number of tapped hole were 0.54 mm for control trees, 0.60 mm for trees taped of one hole, 0.64 mm for trees taped of three holes, 0.33 mm for tapped of five holes and 0.31 mm for trees taped of ten holes, respectively. Closing processes of tapping holes by fusion materials was fast in the order of DB ointment, stirofoam, control and bamboo vinegar. Especially, tapped holes in the case of DB ointment was completely healed within 4 months. Therefore, DB ointment should be used to minimize damage on tree growth and secure resources for sap collection of A. mono.

• Korean Journal of Environmental Biology
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• v.18 no.3
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• pp.315-322
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• 2000

Effects of the simulated acid rain on the growth response and the structural features were studied with the 3 month old seedlings of G. biloba and P. thunbergii treated with acid rain of pH 5.6, 4.0, 3.2, and 2.4. The diameter and area of tracheid cells in the transectioned stem of G. biloba decreased with acidity of simulated acid rain. The wall thickness of tracheid cells was the thinest at pH 2.4, but there was no different at other levels of pH. Increasing of the acidity, the height of tracheid cells were reduced steadily. The diameter and area of tracheid cells of the transectioned root reduced with decreasing pH of acid rain, but those at pH 3.2 were larger than those at control. The wall thickness and height of tracheid cells of root were gradually decreased with acidity of acid rain. The size variation of the fusiform cambial initials in the stem of G. biloba sections tangentially showed a shortening tendency with treatment of acid rain. The length of ray initials was the shortest at pH 2.4 and reduced with decreasing pH of acid rain. The diameter, area, wall thickness, and height of the tracheid cells in P. thunbergii stem and root decreased with decreasing pH of acid rain. The areas of the pith, cortex, and xylem in P. thunbergii treated with acid rain decreased, but the cortex and pith areas increased significantly after exposure to acid rain of pH 3.2 compared with control.

• Journal of the Korea Concrete Institute
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• v.23 no.1
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• pp.87-98
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• 2011

Crack formations are inevitable in reinforced concrete structures. To estimate crack widths, empirical formulae are used widely and indirect crack controling methods of limiting bar spacing and bar diameter are also used due to their simplicity. In EC2, the characteristic crack width is calculated by multiplying maximum crack spacing and average strain. In this study, limit values of maximum bar spacing and bar diameter are examined as the material characteristics are varied. Two models of tension stiffening effect and maximum crack spacing and their effects are evaluated. The obtained results are compared with the values obtained using KCI method. The results showed that a significant difference is found when two tension stiffening effect are employed, and an under-estimation is found when 2nd order tension stiffening effect and maximum crack spacing limit from Part II were implemented. Therefore, a rational indirect crack control method attained using the tension stiffening effect of 2nd order form is needed. Also, a consistency in serviceabiliy analysis in flexural members needs to be secured. In order to achieve these goals, two crack controling models are suggested.

• Journal of Biomedical Engineering Research
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• v.22 no.6
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• pp.503-510
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• 2001

In this paper. we describe a 32-channel bioimpedance measurement system It consists of 32 independent constant current sources of 50 kHz sinusoid. The amplitude of each current source can be adjusted using a 12-bit MDAC. After we applied a pattern of injection currents through 32 current injection electrodes. we measured induced boundary voltages using a variable-gain narrow-band instrumentation amplifier. a Phase-sensitive demodulator. and a 12-bit ADC. The system is interfaced to a PC for the control and data acquisition. We used the system to detect anomalies with different resistivity values in a saline Phantom with 290mm diameter The accuracy of the developed system was estimated as 2.42% and we found that anomalies larger than 8mm in diameter can be detected. We Plan to improve the accuracy by using a digital oscillator improved current sources by feedback control, Phase-sensitive A/D conversion. etc. to detect anomalies smaller than 1mm in diameter.

• FLOWER RESEARCH JOURNAL
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• v.16 no.4
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• pp.234-238
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• 2008

This experiment was conducted to investigate the effect of growth retardants such as CCC and diniconazole in grafted cactus for control shipping product of grafted cactus, which had high degree of dependence upon export. The PGRs were 50, 100, 150 $mg{\cdot}L^{-1}$ CCC and diniconazole, respectively. Treatment of diniconazole and CCC not reduced diameter on Gymnocalycium mihanovichii var. friedrichii but number of tubercle reduced significantly according to the increase of diniconazole treatment, control was 7.2 tubercles, but with 100 $mg{\cdot}L^{-1}$ diniconazole was 6.4 tubercles. Treatment of diniconazole and CCC reduced significantly diameter and tubercle number on Chamaecereus silvestrii f. variegata at higher concentration. Diameter and height reduced significantly the treatment of CCC with 3.3 and 13.4 mm of 150 $mg{\cdot}L^{-1}$, respectively. Dry weight of root, rootstock and scion decreased at higher concentrations of CCC and diniconazole in Chamaecereus silvestrii f. variegata. The most effective method of plant growth retardants for controlling of shipping time was the 150 $mg{\cdot}L^{-1}$ CCC treatment.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.72-79
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• 2016

The fungal morphologies and pellet sizes were controlled in acetophenone reduction by Rhizopus oryzae. The acetophenone conversion and (S)-phenylethanol enantiomeric excesses (e.e.) reached the peak after 72 h of incubation when using pellets with 0.54 mm diameter, which showed an excellent performance compared with suspended mycelia, clumps, and pellets with 0.65 or 0.75 mm diameter. Furthermore, nano-sized acetophenone was used as a substrate to improve the performances of biotransformation work. The results showed that the conversion of nanometric acetophenone and (S)-phenylethanol e.e. reached the maximum (both >99%) after 32 h of incubation when using 0.54 mm diameter pellets, at least 24 h in advance of the control group. On the other hand, Tween 80 and 1, 2-propylene glycol showed low or no toxicity to cells. In conclusion, pellets and acetophenone nanoemulsions synergistically result in superior performances of acetophenone reduction.

• Advances in aircraft and spacecraft science
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• v.4 no.6
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• pp.701-709
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• 2017

One of the components that used in the satellite thermal control subsystem is the Mechanically Pumped Fluid Loop (MPFL) system; this system mostly used in geosynchronous orbit (GEO) satellites, and can transfer heat from a hot point to a cold point using the fluid which circulated in a closed loop. Heat radiates to the deep space at the cold plate to cool down the fluid temperature. In this research, the radiative heatexchanger (RHX) for a MPFL system is optimized. The genetic algorithm has been used for minimizing the total mass and pressure drop by considering a constant transferred heat rate at the heat exchanger. The optimization has been done in two cases. In case I, two parameters are considered as a goal function, so optimization is performed using NSGA-II method. Results of optimization are shown in the pareto diagram. In case II, the diameter of pipe is considered constant, so the optimized value for distances of the parallel pipes is obtained by using the genetic algorithm, in which the system has the least total mass. Results show that in the RHX, by increasing the pipe diameter, pressure drop decreases and total mass increases. Also by considering a constant value for pipe diameter, an optimum distance between pipes and pipe length are obtained in which the system has a minimum mass.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.1
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• pp.25-33
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• 1998

An experimental study has been carried out to obtain optimal conditions for turbulent mixing of two fluid streams at various angle branches by a flow visualization method. The main purpose of this study is the utilization of flow visualization method as a fast and efficient way to find the optimal mixing conditions when several flow control parameters are superimposed. It is verified that the optimal conditions estimated by flow visualization method have good agreement with the concentration field measurements. The results demonstrate that the diameter ratio is mainly attributed to the mixing phenomena than the branch pipe angle and the Reynolds number. The most striking fact is that there exists the best diameter ratio, d/D.ident. O.17, which requires the minimum momentum ratio in the range of the present experiment. The velocity ratio for the optimal mixing condition has a value within 2 to 16 according to the different flow parameters.