• The Plant Pathology Journal
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• v.16 no.5
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• pp.247-251
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• 2000

Latent infections of healthy-appearing oaks of Hypoxylon atropunctatum complicates field studies by interfering with inoculation experiments to follow pathogenesis, fungal development and reproduction of this canker rot fungus. Mutants with unique and easily scorable phenotypes would be useful for inoculation studies. There is a broad range in the capacity of wild-type isolates to utilize nitrate as a sole nitrogen sources. Several types of nitrate-nonutilization mutants (nit1, Nit3, NitM) were selected from nitrate-utilizing wild-type isolates. Also, a few mutants of Hypoxylon atropunctatum were selected that could only grow poorly on basal medium supplemented with various nitrogen sources and even on yeast extract agar. These unknown mutants need to be characterized further. Nit mutants of Hypoxylon atropunctatum were readily selected, grew well and were recovered after inoculation into oak stems. These results suggest that nit mutants could be useful for inoculation studies in trees that contain latent infections.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.92-95
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• 2002

Bioavailability study was conducted to elucidate the relationship between sorption/desorption and biodegradation of sorbed phenanthrene in seven different soils. Mineralization kinetics was determined for phenanthrene-sorbed soil slurries inoculated with Pseudomonas putida (ATCC strain 17484). Two biodegradation models were used to fit mineralization kinetics; (i) a first-order degradation model and (ii) a coupled degradation-desorption model. The biodegradation rates were in order of vermicompost >Bion peat > 50% organoclay > Pahokee > blank (no soil, medium only) > montmorillonite > Ohio shale. The mineralization rate constants increased as desorption-resistance of phenanthrene increased. Among the tested sorbents, active biodegradation of phenanthrene was observed in vermicompost and Bion peat. Biodegradation in these two sorbents exhibited little lag time and a high maximum mineralized capacity. The role of sorption/desorption in bioavailability of phenanthrene sorbed in soils was discussed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.391-394
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• 2003

The applicability of in situ microbial filter or biobarrier technology for the remediation of soil and groundwater contaminated with chlorinated solvents was investigated. The efficiency and rates of reductive dechlorination of chlorinated solvents are known to be highly dependent on hydrogen concentration. In this study, the effect of electron donors on the reductive dechlorination of PCE was investigated using vermicompost (worm casting) and peat as permeable reactive barrier medium The effect of organic acids (lactate, butyrate and benzoate), yeast extract and vitamin $B_{l2}$ on the reductive dechlorination was investigated. Compared to the control (no electron donor added), addition of electron donors stimulated the dechlorinated rate. Among the electron donor treatments, lactate/benzoate amendment exhibited the highest dechlorination rate. Since vermicompost and peat are inexpensive and biodegradable and have high sorption capacity, they could be successfully used as biobarrier media, especially when electron donors (for example, lactate/benzoate) are added.d.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1663-1664
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• 2008

Many years ago, most of thermal power plants built in this country were of subcritical pressure, of medium or small size, of constant pressure operations and of drum type steam generators with circulation type boilers. But, nowadays almost all of them were of high efficiency, of supercritical pressure, of big capacity, of sliding pressure operations, and of once through type steam generators. Presently built once through boilers introduce turbine bypass systems to variable pressure operation which eliminates unexpected materials in boiler tube during startup, minimizes fuel loss by short startup period and eventually improve both total efficiency and power system stability.

• Earthquakes and Structures
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• v.14 no.2
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• pp.95-102
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• 2018

Seismic fragility curves of concrete cylindrical tanks are determined using the finite element method. Vulnerabilities including sloshing of contents, tensile cracking and compression failure of the tank wall due to bending are accounted for. Effects of wall flexibility, fixity at the base, and height-diameter ratio on the response are investigated. Tall, medium and squat tanks are considered. The dynamic analysis is implemented using the horizontal components of consistent earthquakes. The study shows that generally taller tanks are more vulnerable to all of the failure modes considered. Among the modes of failure, the bending capacity of wall was shown to be the critical design parameter.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1091-1097
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• 2002

Capacitated goat spermatozoa generated diacyl glycerol (DAG) when suspended in Krebs-Ringer bicarbonate medium and induced by progesterone or $Ca^{2+}$ ionophore A23187. We have added Sn-1-oleoyl-2-acetyl glycerol externally, to study the effect of DAG in goat sperm acrosomal exocytosis. Addition of neomycin abolished the DAG generating capacity of progesterone in a dose dependent manner, suggesting the involvement of a phosphoinositidase C activated phospholipase C system in the process. The level of increase in phosphatidic acid was considerably low and was produced well after the DAG generation thereby suggesting the involvement of a DAG kinase which phosphorylates DAG to produce PA. The inhibition of progesterone mediated effect by inhibitors of $GABA_A/Cl^{-}$ channel and $Ca^{2+}$ channels further supports the evidence that the events of binding of agonist to the receptor(s), opening of $Ca^{2+}$ channels and the activation of phospholipase C are reconciled to perform the function of acrosome reaction in capacitated goat spermatozoa.

• International Journal of Fluid Machinery and Systems
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• v.10 no.3
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• pp.209-217
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• 2017

The paper presents two novel concepts of increasing the energy storage capacity at pumped storage power plants, both existing and new projects. The concepts utilize compressed air as a working medium to displace water from a volume originally not available for storage. The concepts are likely to give additional storage volume at a low cost, however, much development and many investigations are needed before the concepts can be shown to be technical and economical feasible solutions for energy storage. The concepts are disclosed so that researchers and utilities can start those investigations, hopefully helping the green transition by providing highly valuable energy storage for a future renewable energy having a much higher share of renewable energies than the current systems.

• Journal of Pharmaceutical Investigation
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• v.40 no.5
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• pp.263-267
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• 2010

Nanoemulsions have been widely investigated for many years because of their attractive and unique characteristics. Nanoemulsions are composed of oil, surfactant, co-surfactant and water. Especially, cosurfactant plays a critical role in formation of nanoemulsions. In pharmaceutical area, a pre-concentrate form of nanoemulsions which is known as self-nanoemulsifying drug delivery systems (SNEDDS) was available for some water-insoluble drugs. In this study, we investigated the functional behaviors of cosurfactant in design of SNEDDS and nanoemulsions. Cremophor RH 40$^{(R)}$, Propylene carbonate and medium chain triglyceride were selected for surfactant, cosurfactant and oil, respectively. Cyclosporine was employed as a drug. Phase diagrams showed the area of isotropic o/w region which forms o/w nanoemulsions was not significantly affected by the compositional ratio of cosurfactant. But, drug solubilization capacity, droplet size of nanoemulsions and drug release rate were greatly affected by the cosurfactant.

• Proceedings of the Korean Geotechical Society Conference
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• 1992.10a
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• pp.137-144
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• 1992

This paper reports a case study of dynamic consolidation. The objective of the study is to evaluate the effectiveness of ground improvement at the site for Hyundai Petrochemical Compound constructed at Daesan-Myeon, Seosan-Gun in the western shores of Korea. The site ground was prepared by filling on the existing soft marine deposit which consists of a loose granular soil layer and a medium stiff clay layer. For the stabilization of site ground, the compaction was executed in three different procedures with same pounder weigh, drop height and imprint spacing. The post investigation showed that the object was successfully achieved indicating a significant increase of bearing capacity of the treated ground. In this study the effectiveness of dynamic consolidation is evluated for various factors the applied energy, temping sequences, the radial distance from the imprint location and the depth of bed rock.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.113-118
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• 2011

Many kinds of dynamic absorbers have been used to reduce the vibration of machineries and structures. In the typical ones, however low damping capacity, durability and limited install condition restrict their application. In this study, high damped dynamic absorber was proposed for diesel generator set. Developed absorber is composed with mass and coil springs. Silicone oil was filled inside the narrow gap between mass and casing. Viscous damping of silicon oil act as additional damping so that proposed dynamic absorber is suitable for D/G set which have adjacent resonance frequency to operation speed. The performance of the dynamic absorber was confirmed through the actual test on diesel engine generator set.