• Progress in Superconductivity
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• v.7 no.1
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• pp.52-57
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• 2005

[ $YBa_{2}Cu_{3}O_y$ ] superconducting films were prepared on $LaAlO_3$(100) single crystal substrate by spray pyrolysis method. The precursor solution was prepared by dissolving nitrate powders in de-ionized water. Both of ultrasonic and concentric nebulizers were used in order to generate fine droplets of precursor solution. C-axis oriented films were obtained at deposition temperature of $750\~850^{\circ}C$ and working pressure of 100 Torr and 500 Torr. In case of ultrasonic nebulizer, films showed rough and porous surface morphology due to formation of enormous droplets, while smooth and dense films were obtained for concentric nebulizer. A transport $J_c$ value of $0.43\;MA/cm^2$ at 77 K and self field was achieved on $LaAlO_3$(100) single crystal substrate.

• Korean Institute of Interior Design Journal
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• no.9
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• pp.98-107
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• 1996

The purpose of this study is to find out the characteristics of the office space as designed by Gwathemy Siegel and thereby to understand the current trend of interior design of working space in the United States. Unlike most architects, Gwathmey Siegel have extended themselves into interior designing of over twenty offices including law firms, financial institutions and design firms and have successfully won reputation as interior designers. They have distinguished themselves by their ability to turn up and take advantage of the possbility of shaping in a given structure. Their liberal use of fixed furniture and architectural lighting , in addition to ceilings and walls , set them apart from others in the field . The major design elements and principles of Gwathmey Siegel include, among others : 1) Curved and slanted walls on the floor plans endow the office space with forms. Fixed furniture and architectural lighting frequently serve as from -creating elements. 2) The openness of the reception and waiting areas and the irregularity of the corridor walls add a sense of variety in the office. 3) In terms of color and materials, subtle changes of texture and value and the various patterns of joint lines further enrich the space. 4) The principle of symmetry , rough or partial , as applied in the layout of rooms and furniture creates a sense of balance in the space.

• Journal of the Ergonomics Society of Korea
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• v.34 no.6
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• pp.549-561
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• 2015

Objective: The purpose of this study was to investigate the job stress factors of mobile communication network construction workers using survey based on 'Job stress factors evaluation tool for Koreans' that was developed by KOSHA in 2003. Background: Due to the rapid growth of penetration rate of smartphone, the necessity of LTE service changing from 3G network was brought up. The demand of LTE network construction in a short period of time leads to the aggravation of the job stress of mobile communication network construction workers. Method: Two hundred and fifty workers who were in the mobile communication network industry participated in this study, and among them 206 responses were analyzed for this study due to the unreliability and insincerity of responses. The eight job stress factors which are physical environment, job demand, job autonomy, relation conflict, job instability, organizational system, inadequate compensation, workplace culture were analyzed. Results: The job stress factors of mobile communication network construction workers were compared to those of other industry workers, and other work related characteristics were analyzed. The results showed that the stress level of a physical environment and job requirement were relatively higher than those of manufacturing industry workers, meaning that mobile communication network construction workers have rough working conditions and increased amount of work due to the demand of LTE network construction. The stress level of physical environment for outdoor job workers was relatively higher than that of indoor job workers. With the analytical result for level of job satisfaction, significant difference was observed (p <0.05) with every factor, and the job stress was found the highest with those not satisfied with every factor Conclusion: From the results of this study, the work loss due to the job stress could be prevented, and accurate stress factors could be removed at the workplace. Application: The results of this study may not represent the whole mobile network construction workers, the effort for job stress management is needed to improve the work efficiency and the workers' quality of life.

• Advances in environmental research
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• v.9 no.3
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• pp.191-214
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• 2020

The rise in population and industrialization accounts for the generation of a huge amount of wastewaters. The treatment of this wastewater is obligatory to safeguard the environment and various life forms. Conventional methods for high strength wastewater treatment coming out to be ineffective. Advanced oxidation processes (AOPs) for such wastewater treatment proved to be very effective particularly for the removal of various refractory compounds present in the wastewater. Ozone based AOPs with its high oxidizing power and excellent disinfectant properties is considered to be an attractive choice for the elimination of a large spectrum of refractory compounds. Furthermore, it enhances the biodegradability of wastewaters after treatment which favors subsequent biological treatments. In this review, a detailed overview of the AOPs (like the Fenton process, photocatalysis, Electrochemical oxidation, wet air oxidation, and Supercritical water oxidation process) has been discussed explicitly focusing on ozone-based AOPs (like O₃, O₃/H₂O₂, O₃/UV, Ozone/Activated carbon process, Ozone/Ultrasound process, O₃/UV/H₂O₂ process). This review also comprises the involved mechanisms and applications of various ozone-based AOPs for effective municipal/industrial wastewaters and landfill leachate treatment. Process limitations and rough economical analysis were also introduced. The conclusive remarks with future research directions also underlined. It was found that ozonation in combination with other effective AOPs and biological methods enhances treatment efficacies. This review will serve as a reference document for the researchers working in the AOPs field particularly focusing on ozone-based AOPs for wastewater treatment and management systems.

• Journal of Biosystems Engineering
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• v.34 no.5
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• pp.315-324
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• 2009

Various types of vibration are transmitted to operators of agricultural tractors while working in the field. Most harmful vibration to human body is ride vibrations with low frequency ranging from 1 to 10 Hz, caused by rough terrain. These ride vibration has vertical and rotational components. This study was conducted to develop an active seat suspension system with two degrees of freedoms, enabling effectively reduce vibrations in vertical and pitch motions. Therefore, a mechanism for the active seat suspension was developed, and an electro-hydraulic servo system and a controller to drive the active seat suspension system were also developed in this study. A simulation model was developed to evaluate how the active seat suspension system effectively reduce the vibrations transmitted to the base of seat. Active seat suspension was optimized to enhance the performance using the developed simulation model. The performance of the seat suspension system was evaluated according to the test codes described in EEC78/764 in order to investigate the feasibility of application to agricultural tractors. The result showed that the developed active seat suspension system could reduce the magnitude of vertical vibration up to 80% for the input vibrations according to the test codes described in EEC78/764. The system could reduce the rotational displacement of ${\pm}\;2.5$ degrees up to 50% for the pitch vibration on the average in the frequency range of 1 to 2 Hz.

• Korean Journal of Materials Research
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• v.11 no.7
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• pp.537-544
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• 2001

Anatase $TiO_2$thin films as a photocatalyst were prepared by the reactive magnetron sputtering process. The $TiO_2$thin films were deposited on Si substrates under the various conditions : oxygen partial pressure, working pressure, sputtering time, and D.C. power. The photocatalystic degradation of $TiO_2$thin film have been studied to examine the contribution of surface morphology and crystallinity. The thin films with a good crystallinity or a rough surface showed a high photocatalytic degradation rate on phenol and E.coli 078 experiment. Compared with that of only UV radiation, the photocatalytic efficiency of $TiO_2$thin film under the UV radiation and the $O_2$ flow increased. We found that the crystallity and the morphology were the important factors on the photocatalytic efficiency of TiO$_2$thin film.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.4 no.2
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• pp.229-243
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• 1997

Especially in NICU(Neonatal Intensive Care Unit), handwashing is an important factor in decresing nosocomial infections due to reduced immunity, prematurity and various invasive procedures. The purpose of this study was to investigate the basic characteristics related to handwashing by NICU nurses. It was composed of three parts ; questionnaire survey I (genoral characteristics of handwashing), questionnaire survey II(the awareness degree of handwashing importance) and actual performance. This study was performed from Oct. 8 to 14 in 1994. The results of this study were as follows ; 1. Frequency of handwashing were different by shift of working about 47.1% of the respondents. They were washing most frequently during day-shift about 75% of above. According to self evaluation to handwashing frequency, 64.7% of the respondents said their frequency of handwashing was inadequate, because of being too busy.(45.1%), bothering caused by detergent or disinfectant(17.6%), and too far from handwashing facilities(17.6%). 2. The most common handwashing agent was soap(88.2%), 52.9% of the subjects experienced adverse effects after handwashing ; rough hand(44.5%), dryness(33.3%) All subjects washed their hands with running water, and 70.6% of the subjects washed upto wrist. In duration of handwashing, 52.9% of subjects washed hands 5 to 10 seconds, 29.5% of them did 11 to 15 seconds. 3. 29.4% among subjects had participated to take in the handwashing educational program. About 60% responded they would like to take the course of handwashing if possible. 4. The important nursing activities that need handwashing were chaning of caring ostomy, suctioning, chaning IV dressing site. On the other hand, they responded handwashing was not essential before dealing with omitus, before and after transfering machine, before chaning diaper(stool) 5. Handwashing performance was 61.7%. Among seven nursing activities, suctioning(73.4%) was the highest, the next was dealing with discharge or sampling(71.1%), the lowest was bathing(34.6%). The performance was better after(70.2%) nursing activities that before(52.5%), and day(63.6%) or evening(68.3%) shift than night(56.7%)

• Journal of computational fluids engineering
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• v.21 no.1
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• pp.50-57
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• 2016

In various industries related with construction and military machinery, a large amount of power is normally required because such machinery operations, such as digging or breaking, take place under difficult working conditions in a rough environment. Thus, a hydraulic system needs to be applied as the major power transfer system. To produce and supply hydraulic power depending on the various load conditions, a hydraulic piston pump is utilized as a typical power source for a hydraulic system. In the present study, numerical simulations were conducted using the commercial program, Ansys CFX 14.5. To lubricate the moving parts as the pump starts to operate, a small amount of oil leaks out through the clearance between the orifice in the piston-shoe and the recess at the swash-plate. Taking this into consideration, a cylindrically shaped computational domain was modeled to maintain the same equivalent leakage area. To validate the numerical method applied herein, the numerical results of the flow rate at the discharge port were compared with the experimental data, and a good agreement between them was shown. Using the verified method, the effects of the discharge pressure and the angle of the swash-plate were also evaluated under several load conditions. The results of the present study can be useful information for a hydraulic piston pump used in many different manufacturing industries.

• Journal of the Korean Society of Fashion and Beauty
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• v.5 no.3
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• pp.111-117
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• 2007

Essential oils aims to rejuvenate and beautify medical skin care the body through the use of essential oils, and generally to improve our outward appearance. Much of this section fouses on the different methods by which essential oils can be used to improve the complexion or to treat specific medical care skin conditions. Beauty, however, is not just skin-deep. The condition of the medical care express the overall health of an individual. A relaxed attitude, together with a well-balanced diet, enough exercise, and a daily intake of plenty of spring water or herbal teas, all help to keep the system in top condition. Essential oils is a healing art which has powerful effects on both mind and body. The vital element in essential oils is the pure oils which are extracted from various part of different plants. The key to medical aromatherapy care lies in its dual use of essential oils and medical care massage, thus masking full use of two of our most important senses-smell and touch. Medical aromatherapy care is holistic, working mainly on the nervous system and including the head and body as part of the same treatment. Using pressure points along the spine, Medical aromatherapy care on the autonomic nervous system and has an immediate effect of relexation. In directly it also acts on mood. Many of the medical massage movements help lymphatic drainage. Essential oils have many different qualities; they can be relaxing or invigorating and are generally antisepic and antibacterial. Medical aromatherapy care can have psychological benefits. The power of essences in healing has been recognized in the treatment of insect bites. Clove, thyme, sandalwood, and lavender are a few of the essences that have antiseptic. Essential oils effect the dry skin for small visual pores, dull matte finish, rough sandy feeling, tantskin. Essential oils effect the mature/sun damaged skin for some red or couperose areas, loose saggy skin, exposure to a lot of ultraviolet light. Essential oils effect the medical care nomal skin good elasticity, healthy color(good circulation), smooth terture.

• Journal of Korean Society of Forest Science
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• v.113 no.2
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• pp.164-169
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• 2024

In South Korea, most felling operations involve the use of chainsaws due to steep and rough terrains. This felling technique is responsible for approximately 80% of all fatalities mainly due to unpredictable felling directions. Therefore, readjust monitorised felling is imperative to improve safety in different working conditions. This study examined the effect of wedging on felling direction error and productivity during felling operations. When wedging was applied, a felling direction error within 22° and a productivity of 0.63 m³/min were obtained. These results show a decrease in mean directional error and a dimish in productivity. Thus, although wedging reduces productivity, it is a necessary strategy to improve safety.