• Particle and aerosol research
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• v.14 no.4
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• pp.89-95
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• 2018

People's environmental concerns for fine particles in Korea lead to the strong necessity of improving the performance of environmental control systems. Wet electrostatic precipitators (ESPs) are considered as one of the alternatives to overcome the limit of previous dry ESPs, the re-entrainment of collected particles during rapping and back corona problem for high electrical resistivity dusts etc. In this study, a wire-cylindrical ESP with a thin water film has been developed. Particle collection characteristics were compared in the ESP with operations of water film on and off. Particle collection efficiencies at various applied voltages as well as voltage-current curves were almost the same in the ESP with and without a water film. Particle collection performance for PM1.0, PM2.5 and PM10 in the wet ESP with a water film was constantly maintained with operation time even in the high dust loading environment. This results indicate that a uniform water film in our wet ESP was successfully formed with a very thin layer without any dry spot and therefore could continuously clean the collected particles on the inner wall of the ESP without any performance degradation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.845-847
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• 2014

In recent years, the mobile OS market, enlargement and, at the same time, Android has mounted various smart phones and feature air conditioning, smart TV, cleaning robot, camera, etc. that the number is being spread at a rapid pace. But a lot of devices to control the modules and applications at once, this is not a device for controlling the dissemination of applications all in one place, and in charge of the devices that allow you to manage applications are lacking. Accordingly, in this paper, use the Web Server registered in the appliance can be controlled by management, Web access, is proposing and designing the system. This is the current research is actively in progress in the field of IoT (Internet of Things) would be utilized.

• Safety and Health at Work
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• v.10 no.3
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• pp.265-274
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• 2019

Background: Methyl alcohol poisoning in mobile phone-manufacturing factories during 2015-2016 was caused by methyl alcohol use for cleaning in computerized numerical control (CNC) processes. To determine whether there were health complications in other workers involved in similar processes, the Occupational Safety and Health Research Institute conducted a survey. Methods: We established a national active surveillance system by collaborating with the Ministry of Employment and Labor and National Health Insurance Service. Employment and national health insurance data were used. Overall, 12,048 employees of major domestic mobile phone companies and CNC process dispatch workers were surveyed from 2016 to 2017. We investigated methyl alcohol poisoning by using the national health insurance data. Questionnaires were used to investigate diseases due to methyl alcohol poisoning. Results: Overall, 24.9% of dispatched workers were employed in at least five companies, and 23.9% of dispatched workers had missing employment insurance history data. The prevalence of blindness including visual impairment, optic neuritis, visual disturbances, and alcohol toxicity in the study participants was higher than that reported in the national health insurance database (0.02%, 0.07%, 0.23%, and 0.03% versus 0.01%, 0.07%, 0.13%, and 0.01%, respectively, in 2015). Moreover, 430 suspicious workers were identified; 415 of these provided an address and phone number, of whom 48 responded (response rate, 11.6%). Among the 48 workers, 10 had diseases at the time of the survey, of whom 3 workers were believed to have diseases related to methyl alcohol exposure. Conclusion: This study revealed that active surveillance data can be used to assess health problems related to methyl alcohol poisoning in CNC processes and dispatch workers.

• International journal of advanced smart convergence
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• v.8 no.3
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• pp.27-38
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• 2019

I reviewed about dyeing fastness and functional properties of the non-mordant dyed cotton and iron mordant dyed cotton with astringent persimmon juice. In the UV-VIS spectrum of astringent persimmon juice, the maximum absorption wavelength of the juice was 272.0 nm, which was a characteristic peak of tannin. In dyeing fastness, light fastness of the non-mordant dyed cotton was a little low at grade 2~3. But by the iron mordant treatment, the light fastness was good at grade 4. Dry cleaning fastness to discoloration and contamination was excellent at grade 4~5 for both the non-mordant dyed cotton and iron-mordant dyed cotton. Their rub fastness were grade 3 and grade 2~3 respectively, in the dry condition, and grade 2~3 and grade 3 respectively, in the wet condition. In the perspiration fastness of the non-mordant dyed cotton, the discoloration from acidity and alkalinity was grade 3~4 and grade 3, respectively, and contamination from acidity and alkalinity was relatively good at grade 4. Meanwhile, in the perspiration fastness of the non-mordant dyed cotton, discoloration from acidity and alkalinity was fair, both recording grade 3~4, and contamination from acidity and alkalinity was very good, both recording grade 4~5. In the ultraviolet protection effect of the non-mordant dyed cotton and iron-mordant dyed cotton, the ultraviolet protection factor was both 50+, both of which showed an excellent ultraviolet blocking effect. And the protection rate of UV-A appeared 98.4% and 99.1%, respectively, and the protection rate of UV-B showed 98.7% and 99.2, respectively. In addition, both exhibited an excellent deodorization rate over 99.9% or more, irrespective of the passage of time. Also, both showed an excellent antimicrobial activity over 99.9% or more against Staphylococcus aureus and Klebsiella pneumoniae.

• Convergence Security Journal
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• v.18 no.2
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• pp.149-158
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• 2018

Military officials in Korea are forced to change jobs early due to the retirement age after active service. Measures are needed in view of the 55% average employment rate of middle and long term soldiers during the last five years. The last government of Park Geun-hye push ahead creating of 50,000 jobs in discharged soldier with policy, but the results were not great. Therefore, it is time to drastically change the government's efforts to create large-scale jobs for discharged soldiers. It is necessary to break away from the traditional ways of expanding opportunities for employment at the academic level. So it became necessary for discharged soldiers to actively review ways to build their own organizations. For such reasons, this study presents a measure to create job through food service, Security personnel training and Manpower provision business, Special Soldier Control and Training Center Operation business, Han River Water Cleaning Project, Caring business, and delivery business by establishing their own social cooperation to create jobs for discharged soldiers.

• Journal of architectural history
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• v.28 no.2
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• pp.53-64
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• 2019

This study examines the restoration project of Sokkuram, and introduces its preliminary plans by the architect Pai Ki Hyung. The restoration project started in 1958 with an inquiry committee of the restoration project, and was completed in 1964. Despite having undergone extensive repair work under Japanese supervision from 1913 and 1923, the repair work caused water leakages inside Sokkuram, and regular cleaning work that began in 1933 caused a lot of damage to the sculpture. In result of the surveys, the top priority of this project was to protect the sculptures inside Sokkuram by improving the environment of the cave. At that time, the architect Mr. Pai participated as a head of the fourth field surveyors to plan the restoration project and to design the preliminary plans. He proposed the installation of a double dome structure to prevent further water leakages on the concrete addition that was built up around the grotto by the Japanese. However, in 1961, the Cultural Heritage Committee of Korea examined the plans of Mr. Pai and immediately rejected them. The factors of the rejection were the omitting of entrance design, system of new double dome structure that presses the existing structure, and these changes that had to be made outside of the drainage plans. The repair work of Sokkuram began in 1961, and the main construction was building double dome structure and entrance installation. In this we realize that Mr. Pai's double dome structure plans were very important key concept of this project. This study attempts to demonstrate the double dome installations that Mr. Pai initially proposed, which ultimately remains as emblematic factors of Sokkuram's legacy.

• English & American cultural studies
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• v.14 no.1
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• pp.27-51
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• 2014

Doris Lessing describes a band of revolutionaries who become involved in terrorist activities far beyond their level of competence in The Good Terrorist. Alice Mellings who is from a middle-class family has organized a squat house in London and seems capable of controlling everyone around her and anything about the house. She is seemingly like a housekeeper or a breadwinner. She also likes to be on the battlefront, for instance, demonstrating, picketing and spray-painting slogans. Such is able to easily exploit the others and she increasingly becomes the leader in the house. Recently some critics have focused on the political and social roles of the protagonist who represents a voice of terrorists in the 1980s England. Based on this, The Good Terrorist is read with the concept of the subject of feminism that Gillian Rose adopts in order to show that this subject tries to avoid the exclusion of the master subject. This subject imagines spaces which are not structured through masculinist claims to exhaustiveness. Alice as the subject of feminism shows different roles; she extorts or steals money for the maintenance of the house from her affluent parents; she spends all her time cleaning, fixing, decorating the deserted house; and she looks after the official affairs related to the house with her skills and experiences. She is systematically in charge of the house and sits at the head of the table in the kitchen. But when their activities turn into disaster and their plans fail, Alice willingly decides to close down the house after ousting the members. Here in her extorted gaze it is revealed that she takes control over the working class members of the house who are unable to lead a revolution because of their own problems and thereby the working class are dominated by the middle class. That is, the place is paradoxically recreated based on class differences, which the revolutionaries try to break. By representing the deconstruction and recreation of the place through squat houses, Lessing reveals her implicit feminism in which a new place should be produced crossing the principle of the dichotomy of gender and class.

• Korea Journal of Cosmetic Science
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• v.2 no.1
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• pp.21-31
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• 2020

The aim of this study is to develop a sunscreen stick formulation technology with excellent water resistance and washability. Consumers' needs for sunscreen products are diversifying. Water resistance and ease of washing are both important factors in sunscreen products. However, it is difficult to develop a sunscreen formulation that satisfies these two factors at the same time, because these two elements are in conflict. Fatty acid has a hydrophobic property against the water with low or neutral pH, but when it contacts with soapy water which has high pH, saponification occurs and the fatty acids become surfactants and can be dispersed in the water. Using the reaction characteristics of fatty acids, we can make sunscreen that is highly resistant to water or sweat, but is only selectively removed from soapy water. We found that the sunscreen stick containing fatty acids had better water resistance and washability than the sunscreen sticks without fatty acid. The sunscreen stick containing fatty acids showed a tendency to improve water resistance by scattering ultraviolet rays of long wavelength area by forming insoluble precipitation with divalent ions in tap water after immersion. In addition, an increase in the fatty acid content tended to also increase the ease of cleaning the sunscreen stick. Solid fatty acid was advantageous in improving water resistance than liquid fatty acid, but there was no difference between solid fatty acids and liquid fatty acid in washability. When it comes to stability, the sunscreen stick using liquid fatty acids maintained a high hardness and melting point, and showed no sweating. Based on this study, it is possible to develop an easy washable sunscreen stick formulation technology that has excellent water resistance but is selectively removed only in soapy water.

• Journal of Korean society of Dental Hygiene
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• v.21 no.4
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• pp.441-453
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• 2021

Objectives: This study identified problems and improvements in projects targeted to dental workers in a child-adolescent dental care service. Methods: The subjects were 40 dentists, 43 dental hygienists, and 51 others who participated in service in Seoul. A self-administered questionnaire was used to address the problems and improvements in the project. Descriptive statistics, chi-square test, and one-way analysis of variance were performed using SPSS 23.0. Results: Oral examination was performed by 99.2% of dentists, and some service items such as professional tooth cleaning, fluoride application, and scaling were performed by dental auxiliary personnel regardless of legal duties. The problem was that the subjects took a lot of time in providing services, and students or guardians participating in the project refused to receive preventive dental services. As regards improvements, the insurance fee was the highest (48.1%), followed by the provision of regular services (38.8%), and system improvement and administrative support (35.7%). Conclusions: To activate a child-adolescent dental care service, it is thought that continuous efforts such as providing financial support by the government, education to increase participants' understanding, and social consensus for the participation of service providers and beneficiaries are required.

• Journal of Korean Society on Water Environment
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• v.37 no.6
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• pp.433-441
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• 2021

The aim of this study was to optimize the ozonation and ceramic membrane integrated process for greywater reclamation. The integrated process is a repeated sequential process of filtration and backwash with the same ceramic membrane. Also, this study used ozone and oxygen gas for the backwashing process to compare backwashing efficiency. The study results revealed that the optimum filtration and backwash time for the process was 10 minutes each when comparing the filtrate flow and membrane recovery rate. The integrated process was operated at three different operating conditions with i) 10 minutes for filtration and 10 minutes for ozonation, ii) 10 minutes for filtration and 10 minute for oxygen aeration, and iii) continuous filtration without any aeration for synthetic greywater. The integrated process with ozone backwashing could produce 0.55 L/min of filtrate with an average of 18.42% permeability recovery, while the oxygen backwashing produced 0.47 L/min and 6.26%, respectively. And without any backwashing, the integrated process could produce 0.29 L/min. This shows that the ozone backwash process is capable of periodically recovering from membrane fouling. The resistance of the fouled membrane was approximately 34.4% for the process with ozone backwashing, whereas the resistance was restored by 10.8% for the process with oxygen backwashing. Despite the periodical ozone backwashing and chemical cleaning, irreversible fouling gradually increased approximately 3 to 4%. Approximately 97.6% and 15% turbidity and TOC were removed by ceramic membrane filtration, respectively. Therefore, the integrated process with ozonation and ceramic membrane filtration is a potential greywater treatment process.