• Journal of Distribution Science
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• v.17 no.7
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• pp.65-76
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• 2019

Purpose - The purpose of this study is to investigate economical ventilation effectiveness to reduce hazardous materials exposure and damage of workers by analyzing exposure amount of noxious substances under various ventilation conditions of nail salon for indoor environments. Research design, data, and methodology - This study was carried out with cooperation of Nail shop located in SeongNam city to involve an analysis of the environmental impact indoor air quality, pollutant exposure and economical cost-effectiveness in the nail workplace. The hazardous substances were PM-10(Particulate Matter-10㎛), VOCs(Volatile Organic Compounds) and Formaldehyde, which are the major materials of nail workplace. Results - PM-10 is reduced by about 60% with air cleaner, forced artificial ventilation by 32%, and natural ventilation by about 12%. TVOCs and Formaldehyde showed similar efficiency (80~100%) after natural ventilation and ventilation after 60 minutes. The removal efficiencies of VOCs and formaldehyde were similar to those of natural ventilation and mechanical ventilation system. However, in case of dust, natural ventilation was reduced by artificial ventilation system due to inflow of external dust during natural ventilation. Conclusions - If the pollution degree of outdoor air is not high, air volume is high, and natural ventilation is performed when the air conditioning and heating system is not operated. Even at the end of the work, it keeps operating for 60 minutes to remove the pollutants generated. Results of this analysis demonstrated that the worker environment can be improved by adopting institutional legislation and guidelines for ventilation.

• Journal of Veterinary Clinics
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• v.37 no.5
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• pp.278-281
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• 2020

A 4-year-old Thoroughbred stallion was referred to J&C Equine Hospital with a quarter crack of the right front foot. On visual inspection, there was a medial quarter crack with laminar necrosis. The first step to treat this problem was to remove the necrotized tissue around the crack using Dremel tools, disinfecting crack, administering antibiotics through regional limb perfusion and systemically administering antibiotics and anti-inflammatory drugs consistently. After one month's anti-inflammatory management, the quarter crack was treated successfully using two series of wiring with one week's term and polymethylmethacrylate composites (Equilox^㉿). After treatment, this racehorse successfully resumed training and racing in Korea Racing Authority Seoul Race Course, and won three times, finishing second and third place once, out of thirteen starts.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.458-462
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• 2013

A drainage ditch is normally a component of drainage networks in farming systems to remove surplus water, but at the same time, it may act as a major conduit of agricultural nonpoint source pollutions such as sediment, nitrogen, phosphorus, and so on. The hybrid turbidity reduction system using biodegradable check dam and synthetic polymer was developed in this study to manage pollutant discharge from agricultural farmlands during rainfall events and/or irrigation periods. The performance of this hybrid system was assessed using a laboratory open channel sized in 10m-length and 0.2m-width. Various check dams using agricultural byproducts (e.g., rice straw, rice husks, coconut fiber and a mixture of rice husks and coconut fiber) were tested and additional physical factors (e.g., channel slope, flowrate, PAM dosage, turbidity level, etc.) affecting on turbidity reduction were applied to assess their performance. A series of lab experiments clearly showed that the hybrid turbidity reduction system could play a significant role as a supplementary of Best Management Practice (BMP). Moreover, the findings of this study could facilitate to develop an advanced BMP for minimizing nonpoint source pollution from agricultural farmlands and ultimately to achieve the sustainable agriculture.

• Environmental Engineering Research
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• v.13 no.1
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• pp.1-7
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• 2008

Recently a new technology called the flexible-fiber deep-bed filter (FDF) claimed to replace the conventional sand filter including coagulation and sedimentation filter (CSF) processes in the water treatment plant. Therefore the life cycle assessment (LCA) approach was applied for evaluating the life cycle impacts of FDF compared with those of CSF. The used LCA softwares were the Simapro 6 and PASS and their life cycle impact assessment (LCIA) methodologies were the Eco-indicator 99 and the Korean Eco-indicator, respectively. The goal of this LCA was to identify environmental loads of CSF and FDF from raw material to disposal stages. The scopes of the systems have been determined based on the experiences of existing CSF and FDF. The function was to remove suspended solids by filtration and the functional unit was $1\;m^3$/day. Both systems showed that most environmental impacts were occurred during the operation stage. To reduce the environmental impacts the coagulants and electricity consumptions need to be cut down. If the CSF was replaced with the FDF, the environmental impacts would be reduced in most of the impact categories. The LCA results of Korean Eco-indicator and Eco- indicator99 were quite different from each other due to the indwelling differences such as category indicators, impact categories, characterization factors, normalization values and weighting factors. This study showed that the life cycle assessment could be a valuable tool for evaluating the environmental impact of the new technology which was introduced in water treatment process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.379-388
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• 2016

There are various system defects from weapons manufacturing due to the numerous production processes and various production environments. The first kind of defect is patent defects, which can be detected by visual inspection, functional testing, and existing quality control procedures during the manufacturing process. The second kind is latent defects, which cannot be detected though existing quality management approaches because of the complexity of the system and manufacturing process. To minimize the initial defect problems, environmental stress screening (ESS) is needed to detect the defects, remove them, and improve the product conditions based on the environmental stress conditions of temperature and vibration. We implemented a tool for quantitative ESS effectiveness analysis and profile design automation based on MIL-HDBK-344 and verified it using six scenarios with different temperature stress, vibration stress, and test designs.

• Journal of Korean society of Dental Hygiene
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• v.17 no.6
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• pp.1195-1206
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• 2017

Objectives: The purpose of this study is to analyze relationship between oral health status and subjective oral malodor awareness of public health students. Furthermore, this study aimed to recognize the importance of prevention and treatment of internal and external factors and to contribute to the correct oral health management behavior. Methods: The study subjects were 500 students from 5 health departments of 2 universities located in Jeollanamdo who participated in self-administered survey from September 1 to 15, 2014. For statistical analysis, SPSS 21.0 for Windows was used. Descriptive analysis and a Chi-square test were conducted to investigate the effects of general characteristics, health behavior, oral health behavior, and oral health status on subjective oral malodor awareness. Finally, to investigate the relationship between oral health status and subjective oral malodor awareness logistic regression analysis was performed. Results: Subjective oral malodor awareness was significantly higher in the group requiring dental care with the score of 1.63 (95% CI 1.00-2.65) compared to the group not requiring dental care. Subjective oral malodor awareness was significantly higher in the severe coated tongue group with the score of 5.31 (95% CI 1.45-19.40) and significantly higher in the moderate coated tongue group with the score of 2.56 (95% CI 1.61-4.08). Subjective oral malodor awareness was significantly higher in the often mouth breathing group with the score of 2.13 (95% CI 1.02-4.47) and significantly higher in the sometimes mouth breathing group with the score of 2.66 (95% CI 1.65-4.29). Conclusions: In order to prevent oral malodor, it is emphasized that regular dental checkups, proper brushing after the meal, and brushing of the tongue are necessary to remove the coated tongue. In addition, the use of supplementary oral care products is considered to be a meaningful oral health behavior.

• Journal of Korean society of Dental Hygiene
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• v.10 no.5
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• pp.807-817
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• 2010

Objectives : The purpose of this study was to analyzes the job implementation of dental hygienist at dental hospital(university), dental clinic and general hospital in the city of Gwangju. Methods : The subjects in this study were dental hygienists who worked at dental hospital(university), dental clinic and general hospital in the city of Gwangju. A survey was conducted by post from June 10 to August 10. Out of the collected data, 204 answer sheets were analyzed. Results : 1. 'Medical & Dental history taking', 'Extra & Intra oral examination' and 'Dental hygiene care plane' in dental clinic were significantly higher than dental hospital(university) and general hospital(p<0.001). 'Remove of extrinsic stain' and 'Treatment of hypersensitivity tooth' in dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.001). 'Preventive dental caries treatment' and 'Diet control' were shown the low frequency of job implementation. 2. Almost task elements of dental assistance duty shown that dental hygienists under the 24 years old were significantly higher dental hygienists over the 30 years old(p<0.05) and dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.05) in frequency of job implementation. 3. 'Dental staff supervision', 'Patient management' and 'Dental chart arrangement' shown that dental hygienists over the 30 years old were significantly higher than dental hygienists under the 24 years old in frequency of job implementation(p<0.05). 'Infection control' of dental hygienists over 30 years old was significantly lower than dental hygienists under the 24 years old(p<0.001). Conclusions : The results of this study indicate that a scope of dental hygienists' job need to extend also in order to accomplish a job efficiently, is suggested that the effort is necessary to improve a quality of dental hygienist and to change of recognition of the dentist about dental hygienists' job.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.431-439
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• 2016

Designers are implementing the trial for enhancing human happiness and quality of life. As the happiness factor experienced by each individual is diverse based on human economic growth, absolute design has reached the limitations. A tool to represent the speedy development of change in consumption and problem shooting methods is necessary. Currently, no tool exists that develops in response to changing conditions and subsequent changes. As the solution to this necessity, worm's metamorphosis would be meaningful in design whereby tools exist and necessity as well as solution methods are in advanced change. Rice continues growth following the season, and no single method exists to remove the germs and worms. This study clarified the problems to be resolved by staging the lifetime of rice in 5 stages in environmental changes and conditions. This worm in metamorphosis design is developing brilliantly in biotechnology. However, the environment and conditions that bring happiness to humans do evolve, and this study aims to be the academic research for the design which accordingly replaces the tools.

• Journal of Industrial Convergence
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• v.18 no.1
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• pp.97-107
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• 2020

Since long ago, there has been a saying that "Drink water to quench thirst, drink alcohol to remove anguish and anxiety, and drink tea to recover from fatigue and refresh mind." Tea is really better for body and mind than water when it is drunken long and is valuable Jinda(眞茶) given by mother nature. In particular, curing tea reflecting characteristics of climate changes in all seasons helps in keeping health. Since tea contains the Yin-Yang system, which is a philosophical ideology of ancient people, old predecessors knew which tea they should brew and drink for curing in harmony with Yin and Yang. As a factor that influences component changes of tea, a complex interaction of heaven, earth and man is important and especially, mind of a person to handle tea is most important. Tea is a natural curing drink, which plays a role as a bridge between humans and nature.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.1
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• pp.43-50
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• 2016

NAND flash based storage devices adopts multi-channel and multi-way architecture to improve performance using parallel operation of multiple NAND devices. However, multiple NAND devices consume higher current and peak power overlap problem influences on the system stability and data reliability. In this paper, current waveform is measured for erase, program and read operations, peak current and model is defined by profiling method, and estimated probability of peak current overlap among NAND devices. Also, system level TLM simulator is developed to analyze peak overlap phenomenon depending on various simulation scenario. In order to remove peak overlapping, token-ring based simple power management method is applied in the simulation experiments. The optimal peak overlap ratio is proposed to minimize performance degradation based on relationship between peak current overlapping and system performance.