• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.11
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• pp.1279-1287
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• 2009

An increasingly competitive business environment has been concentrated on industries to reduce the operating costs. Industries such as gas, oil, petrochemical, chemical, and electric power have employed for the operation and used for large equipment or structures that require a high capital investment. In order to meet these requirements, the industries are increasingly moving toward saving the experimental verification and computer simulation. Therefore industries to reduce the maintenance costs without compromising the operational safety have been forced on finding for better and more efficient methods to inspect their equipment and structures. In this study, it focused on the development the real-time non-contract monitoring system as an efficient tool for the experimental study of weld defects based on the relationship between the measured voltage and input parameters.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.3
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• pp.169-173
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• 2006

In-service diagnoses of pipeline facilities are important for a systematic maintenance of them. Field applications by using sealed gamma-ray sources $(^{60}Co,\;^{137}Cs)$ were performed to identify the heterogeneous zone in the pipelines of a distillation tower and a flare stack respectively. From the results, the heterogeneous zones in the pipelines were successfully identified. In the case of the pipeline connected to the distillation tower, a vapor pocket was detected in the fluid under hydrodynamic conditions, which could explain the reason for a decrease of the flow rate. In another case, an area with some amount of catalyst deposits was found at the bottom of the gas pipeline which was connected to the flare stack. And these findings provided important information for the process operators. Diagnosis technique by using gamma radiation sources has been proven to be an effective and reliable method for providing information on a media distribution in a facility.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.347-350
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• 2002

The petrochemical products can cause soil and groundwater contamination during their transportation and the use of the products, and while being contained in underground storage tanks(USTs) throughout the leakage. To treat the contaminated soil, the bioventing method is suitable for the remediation of semi-volatile compounds, such as diesel and kerosene. Biofiltration is one of possible method to treat the off-gas produced in the process of the bioventing. This study is related to the usage, effectiveness of treatment, and feasibility of two types of biofilter system made of ceramic-compost and polymer respectively to treat diesel VOCs at constant retention time of 20 sec. Compost biofilter showed the average removal efficiency of 73 % when the inlet concentration increased to 20 ppmv. Increased the inlet concentration decreased the microbial activities as well as the removal efficiency. On the contrary, the removal efficiency of the polyurethane biofilter was maintained at 88 % at the inlet concentration of 13 ppmv during ten days and was obtained to 80 % at the inlet concentration of 30 ppmv in spite of the drop of the efficiency in the sudden increase of the inlet concentration. At the beginning of the experiment it showed low removal efficiency at low inlet concentration due to the low microbial activity, however, as experiments proceed the removal efficiency could be obtained more than 80% at high inlet concentration.

• Economic and Environmental Geology
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• v.27 no.5
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• pp.459-467
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• 1994

The Gadaeri granite near Ulsan mine is an oval-shape isolated granitic body, and is genetically related to the iron-tungsten mineralization. The Gadaeri granite exhibits calc-alkaline and I-type characteristics, and generally shows the micrographic texture which indicates the shallow depth of emplacement. Consideration of the stratigraphic thickness of Ulsan formation and minimum-melt compositions suggests that the bulk magma crystallized at pressure of 0.5~2.0 kbar under water saturated condition. The evolutionary trend observed in the studied rocks represents that feldspar fractional crystallization has been a major magmatic process at the Gadaeri granite pluton. Different chemical characteristics between the Gadaeri and the Masan-Kimhae granites cannot be explained by fractional crystallization or different degrees of partial melting, and it reflects that the magma source for Gadaeri granite was different from that of the Masan and Kimhae granites.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.2
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• pp.61-71
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• 2023

The purpose of this study is to examine the relationship between POS, JR, and Innovation, and to explore the role of job psychological empowerment as a mediator in this relationship. A structured questionnaire was distributed to 25 companies in the petrochemical industry. PLS-SEM 4 was used to analyze the data of 100 valid responses. These findings suggest that employee empowerment (EMPOW) fully mediates the relationship between job resourcefulness (JR) and Innovation (INNOV). The total effect of JR on INNOV is also significant, with a beta coefficient of 0.234 and a t-value of 3.375. However, when the mediating influence of EMPOW is taken into account, the effect of JR on INNOV is no longer significant, with a beta coefficient of 0.100 and a t-value of 1.610. This suggests that EMPOW plays a key role in the relationship between JR and INNOV and that JR may not have a direct impact on Innovation. The study informs the development of interventions or strategies for promoting Innovation in organizations by identifying key factors that facilitate or inhibit the innovation process. The study further contributes to the development of new theories or models on the relationship between perceived organizational support, job resourcefulness, psychological empowerment, and Innovation.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.193-199
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• 1998

The mixtures of ultra-high molecular weight polythylene (UHMWPE), high density polyethylene (HDPE), process oil (mineral oil) and potassium hexatitanate whisker were melted and mixed at $150^{\circ}C$ for 30min, and prepared by compression molding to the specimen of separator of about $200{\mu}m$ thickness at the same temperature and 5000 psi. Thereafter the pores were formed by extracting process oil with organic solvents. In this study, the range of PR (the ratio polymer to process oil) was varied from 0.1 to 0.5 because the specimen turned into rubbery phase at which PR was below 0.1 whereas it changed into gel phase at which PR was above 0.5. When the specimen was treated with nonpolar organic solvents, process oil was extracted nearly 98%. Tensile strength was $31kg/cm^2$ at PR = 0.426, and resistance of specimen was $37m{\Omega}/cm^2$ at PR = 0.186, and $53m{\Omega}/cm^2$ at PR = 0.426. The $N_2$ adsorption-desorption isotherm showed a hysteresis representing regions of capillary condensation, and the surface area at PR = 0.186 was relatively large as $130cm^2/g$. Potassium hexatitanate whisker was randomly dispersed in between PE layers. It might be that the whisker is intercalated through the PE thin layers oriented by compression.

• Membrane Journal
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• v.24 no.5
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• pp.409-415
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• 2014

This study is aimed to separate propylene and propane using membrane process instead of NCC(Naphtha Cracking Center) $C_3$ splitter. Membrane process is a low energy consumption and eco-friendly process while $C_3$ splitter requires high energy consumption in petrochemical processes. In this study, high performance facilitated transport membrane (FTM) is used for propylene/propane separation. FTM module was prepared on top of porous polyetherimide hollow fiber using PVP/$AgBF_4$/TCNQ. We developed simulation program predicting the membrane separation properties under operation conditions. Separation properties of FTM module for propylene and propane were obtained from the simulation program based on the pure gas permeation data. Based on these results, it is predicted that an one-stage membrane process provides 99.5% of propylene at permeate side from a binary gas mixture of 95/5 vol% $C_3H_6$ / vol% $C_3H_8$ supplied as a feed gas.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.545-550
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• 1998

Succinic acid, valuable $C_4$-dicarboxylic acid as a renewable alternative feedstock, is currently produced commercially by the petrochemical process, but extensive efforts have been devoted to establish the biological process for mass production of succinic acid. In this study, the bioconversion of fumaric acid to succinic acid was investigated. We isolated an Enterococcus sp. RKY1 KCTC 8890P, facultative bacterium, capable of the bioconversion of fumaric acid to soccinic acid very rapidly and efficiently. At batch fermentation, the amount of succinic acid production increased with increase in initial fumaric acid from 40 to 100 g/L. With fumaric acid of 70 g/L, the average specific and volumetric production rate, molar yield were reached up to 0.64 g/g.h, 4.87 g/g.h, and 96.5%, respectively. Maximum concentration of succinic acid of 88.9 g/L was achieved with molar yield of 89% with fumaric acid of 100 g/L in less than 20 hours.

• KSBB Journal
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• v.24 no.1
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• pp.17-24
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• 2009

For the biosurfactant production process at first Candida bombicola, Sphingomonas yanoikuyae, Sphingomonas chungbukensis and Myxococcus flavescens were studied. As the most productive microorganisms C. bombicola, S. yanoikuyae and S. chungbukensis were selected. During many petrochemical industrial processes variable volatile organic componds are produced and they can cause an unpleasent and unhealthy atmosphere. Usually the volatile organic compounds are treated with chemical detergents. The chemical detergents cannot be easily degradable and can be accumulated in the nature. In this study we tried to develop a production process for the biosurfactants, which can substitute some chemical detergents in some chemical processes, with microorganisms. At second the treatment of the volatile organic compounds with the biosurfactants were tested and compared with the treatment with chemical detergent. The production productivities of the biosurfactant with microorganisms were compared. The growth patterns and kinetics of the microbial cells and the surface tension values of the biosurfactants were studied. The changes of the surface tension in variable pH conditions and sodium chloride concentrations were also studied. The volatile organic carbons were treated in a small plant scale. As the result of this study, it indicated that the specific growth rate of S. chungbukensis was the fastest by 0.144 ($hr^{-1}$). For surface tension, C. bombicola (38.1 dyne/cm) had the lowest value, and solubility of the volatile organic carbon was similar in C. bombicola and S. chungbukensis. (Toluene: about 0.1 Unit, Chloroform: about 0.6${\sim}$0.7 Unit, Benzene: about 0.5${\sim}$0.8 Unit). The biosurfactant, which were produced by C. bombicola, was selected for the further study for the volatile organic carbon treatment. With the biosurfactans from C. bombicola could remove the volatile organic carbon about 80% and this removal rate can be comparable with chemical detergent.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.608-614
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• 1999

The counter-diffusion of aromatic compounds such as coronene and tetra-phenylporphine by injection of acetone or tetra-phenylporphine solution was studied on aluminas and silica-alumina used widely as catalysts support. The counter-diffusivity was determined from simulation results by using the counter-diffusion model employing ideal adsorbed solution theory. The counter-diffusivities of aromatic compounds in the catalyst supports were ranged in ${\sim}10^{-15}m^2/sec$ in the desorption process by the injection of excess acetone. In the counter-diffusion process with tetra-phenylporphine solution which have similar concentration with adsorption solution, the counter-diffusivities of coronene were also ${\sim}10^{-15}m^2/sec$, and that of tetra-phenylporphine into pores were determined as ${\sim}10^{-11}m^2/sec$. The counter-diffusivities of coronene desobed from the adsorbent were significantly redyced in comparison with the effective diffusivities when there is counter-diffusion flux. The values mainly depended on the existence of counter-diffusion flux, but not concerned with the species and amount of desorbates.