• Journal of Korean Society on Water Environment
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• v.32 no.1
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• pp.23-29
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• 2016

Ozonation was investigated for its ability to remove pyruvic acid in a laboratory-scale batch reactor under various experimental conditions, including UV irradiation, TiO₂ addition, and variations in temperature. An ozone flow rate of 1.0 L min^-1 and a concentration of 75±5 mg L^-1 were maintained throughout the experiment, and pH, COD, and TOC were measured at 10 min intervals during a 60 min reaction. Our results confirmed that the combination of UV irradiation and photocatalytic TiO₂ in the ozonation reaction improved the removal efficiency of both COD and TOC in aqueous solution at 20℃. Pseudo first-order rate constants and activation energies were quantified based on the COD and TOC measurements. We observed that the O₃/UV, O₃/UV/TiO₂ system increased mineralization and reduced the activation energy (E_a) necessary for pyruvic acid decomposition.

• Journal of Korean Society on Water Environment
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• v.20 no.5
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• pp.466-472
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• 2004

Red mud is formed as a waste during bauxite refining known as Bayer's process. Its main constituents are iron, aluminium, sodium and silica. The disposal of large quantities of wasted red mud causes a serious ecological problem. In this study, the red mud wasted from the bauxite refinery was studied for phosphate removal from aqueous solution according to activation methods. The influence of heat treatment, and neutralization with sea water and acid treatment level for the optimum conditions for phosphate removal have been determined. Heat treatment combined with acid treatment is most suitable for the removal of phosphate from aqueous solution. The optimal condition was activated with 1 N HCl solution after heating in $600^{\circ}C$ during 4 hours. Acid and heat treatment causes sodalite compounds which hinder the phosphate adsorption to leach out. The adsorption data obtained followed a first-order rate expression and fitted well with the Freundlich Isotherm well.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.2
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• pp.233-244
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• 2002

The purposes of this research are to use the buildings efficiently and long, save energies, make the cozy and comfortable environment of residential and living spaces, rearrange the related acts for easy implementation of remodeling, and activate the government's support programs so as to make remodeling activated in a safe mode. The scope and methodology of this research include the review of existing literatures and data on remodeling, census on apartment residents, influence factors, and the development of methods for activation of building remodeling and strengthening of safety management, like activation measures, licensing and ordering regulation updates, etc regarding the remodeling. Safety inspection and in-depth inspection before and after remodeling should be regulated. The construction materials for remodeling should be light weighted and the construction methods which can minimize the impact and vibration during construction should be selected. The improvement of regulation on the remodeling contractor qualification and order method should be updated. If the remodeling is activated and safety management is reinforced by the suggested measures, solving of lack of house, prevention of abuse of resources, and improvement of residential environment could be accomplished rationally.

• Phonetics and Speech Sciences
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• v.2 no.4
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• pp.3-10
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• 2010

The present study aims to investigate neural activations according to the level of code switching in English proficient bilinguals and to find the relationship between the performance of language switching and proficiency level using ERPs (event-related potentials). First, when comparing high-proficient (HP) with low-proficient (LP) bilingual performance in a native language environment, the activation level of N2 was observed to be higher in the HP group than in the LP group, but only under two conditions: 1) the language switching (between-language) condition known as indexing attention of code switching and 2) the inhibition of current language for L1. Another effect of N400 can be shown in both groups only in the language non-switching (within-language) condition. This effect suggests that both groups completed the semantic acceptability task well in their native language environment without the burden of language switching, irrespective of high or low performance. The latencies of N400 are only about 100ms earlier in the HP group than in the LP group. This difference can be interpreted as facilitation of the given task. These results suggest that HP showed the differential activation in inhibitory system for L1 in switching condition of L1-to-L2 to be contrary to inactivation of inhibitory system for the LP group. Despite the absence of an N400 effect at the given task in both groups, differential latencies between the peaks were attributed to the differences of efficiency in semantic processing.

• Journal of Family Resource Management and Policy Review
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• v.23 no.1
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• pp.83-97
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• 2019

This study aims to analyze the elements to enhance and activate the quality of life by establishment of family-friendly environment through face-to-face interviews in family-friendly certified firms in UIsan. As a result, its activation is possible when each party of companies- employees-government tries to change, and its main elements and outcomes are as follows. First, 'management philosophy of the company representative' showed to directly affect development of flat organization culture and system activation, with respect to the companies. Second for employees, 'value changes to prioritize work-life balance' demonstrated to affect the utilizations and establishment of family-friendly systems within the organization as the critical element. Lastly, it is considered for government to be able to activate this if 'delivery system with professionality' is secured to help 'legalization of policy,' company productivity, and work-life balance of employees. On the other hand, further studies on the elements to be able to activate family-friendly certifications and analysis on its justification are required by expanding the number of companied in Ulsan.

• Journal of Environmental Health Sciences
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• v.28 no.3
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• pp.64-71
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• 2002

Hair provides important information about the body's mineral status. Therefore, we have studied the trace elemental distribution in human hair under different inhalation and ingestion environment using neutron activation analysis (NAA). NAA is a powerful analytical method which can be used successfully to determine trace elements in environmental and biological materials. Total diet and six different herbal medicine were analysed to study ingestion environment. Airborne dust in foundry was analysed and compared with outdoor dust to study inhalation environment. Human hairs of common person, herbal medicine taker and foundry worker were analysed to estimate the trace elemental distribution of people under different inhalation and ingestion environment. Analytical results show that herbal medicines contain higher micronutrients such as Ca, Mg, Mn and Cu that total diet and airborne dust in foundry has high Cr. The concentration of Ca, Mg and Mn in hair of herbal medicine taker is two times higher than in hair of common person and Cr con-centration in hair of foundry worker is about three times higher than in hair of common person. These results show that NAA can be used importantly to monitor human health through biological and environmental samples.

• Journal of Environmental Science International
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• v.26 no.11
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• pp.1201-1208
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• 2017

Oxidative degradation of chlorinated ethenes was carried out using heat-activated persulfate. The activation rate of persulfate was dependent on the temperature and the activation reaction rate could be explained based on the Arrhenius equation. The activation energy of persulfate was 19.3 kcal/mol under the assumption that the reaction between the sulfate radical and tricholoroethene (TCE) is very fast. Activation could be achieved at a moderate temperature, so that the adverse effects due to high temperature in the soil environment were mitigated. The reaction rate of TCE was directly proportional to the concentration of persulfate, indicating that the remediation rate can be controlled by the concentration of the injected persulfate. The solution was acidized after the oxidation, and this was dependent on the oxidation temperature. The consumption rate of persulfate was high in the presence of the target organic, but the self-decomposition rate became very low as the target was completely removed.

• Korean Journal of Veterinary Research
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• v.32 no.4
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• pp.663-669
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• 1992

This experiment was carried out to find out the best condition for the parthenogenetic activation of mouse eggs by treating ethanol and hyaluronidase. For the parthenogenetic activation of eggs with ethanol, cumulus cell enclosed or denuded eggs were treated with 7% ethanol in D-PBS for 5, 7 or 9 minutes. For the activation of eggs with hyaluronidase, the eggs with cumulus masses were released into D-PBS with 100 unit hyaluronidase and treated for 10, 12 or 13 minutes. All of the treated eggs were incubated in BMOC-3 solution for 5 hours at $37^{\circ}C$ at an atmosphere of 5% $CO_2$ in air. The types of parthenogenetic eggs were morphologically classified into haploid, diploid, immediate cleavage eggs under an inverted microscope. The results obtained in this experiment were summarized as follows ; 1. High activation rate(99%) had been achieved by treating the eggs with 7% ethanol for 7 minutes. 2. With 100 IU hyaluronidase, high activation rate (94%) had been achieved by treating for 12 minutes. 3. The most frequent type of parthenogenetic eggs activated with ethanol or hyaluronidase was haploid (p<0.05). 4. The eggs collected from 18 to 22 hours post HCG injection showed higher activation rate than the eggs collected at 16 hours post HCG injection. 5. No significant difference (p>0.05) in activation rate was shown in strain of mouse and in presence of cumulus cells.

• Applied Chemistry for Engineering
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• v.23 no.5
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• pp.445-449
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• 2012

The activation process of the membrane-electrode assembly (MEA) is important for the mass production of the polymer electrolyte membrane fuel cell. The conventional activation process for the MEA requires excessive time and hydrogen gas and it might become the barrier for the commercialization of the fuel cell. The conventional activation process is based on hydrolysis of ion conducting membrane. In the study, we suggest the cyclic voltammetry (CV) technique as an on-line activation process and the CV activation process consists of two steps : 1) the humidification of the polymer electrolyte membrane and the electrode with 100% RH humidified nitrogen ($N_{2}$) gas, and 2) the removal step of the oxide layer on the surface of the Pt catalyst with CV cycling. The cycling reduces the activation time of the MEA by 2.5 h and use of hydrogen gas by 1/4.

• Journal of the Korean Institute of Rural Architecture
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• v.6 no.2
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• pp.53-64
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• 2004

The result of this study about application methods of regional heritage are important things. 1. Rural community going ahead Rural Activation Policies applied in regional heritage, have principal experience programs based on visiter's demands. 2. The programs applied regional heritage are most useful application methods of traditional-cultural experience, and following, folk-life and nature environment experience. 3. Insufficient of scheme for applying regional heritage, and specific characters and identity of rural community, is coming out the inadequate plan of community design with comparing other neighborhoods.