• Proceedings of the KSR Conference
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• 2005.11a
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• pp.1190-1195
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• 2005

Biomass burning is a source of greenhouse gases, carbon dioxide, methane, and nitrous oxide. Under the ideal conditions of complete combustion, the burning of biomass produces carbon dioxide and water vapor. Since complete combustion is not achieved under any conditions of biomass burning, other carbon species, including carbon monoxide, methane, non-methane hydrocarbons and particulate carbon are produced. In this study, we analyze the combustion characteristics of rice-husk, such as heat release rate, smoke production rate, the percentage variation of CO and $CO_2$, oxygen consumption rate, and mass loss under different heat fluxes (20, 50 and 70kW). As a result, at 20kW incomplete combustion is occurred so that the percentage of CO is high in initial burning and total smoke release is higher than the others. At 50kW and 70kW, the combustion behaviors is very similar except the variation of CO percentage.

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.195-200
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• 1998

Since the neural network was introduced, significant progress has been made on data handling and learning algorithms. Currently, the most popular learning algorithm in neural network training is feed forward error back-propagation (FFEBP) algorithm. Aside from the success of the FFEBP algorithm, polynomial neural networks (PNN) learning has been proposed as a new learning method. The PNN learning is a self-organizing process designed to determine an appropriate set of Ivakhnenko polynomials that allow the activation of many neurons to achieve a desired state of activation that mimics a given set of sampled patterns. These neurons are interconnected in such a way that the knowledge is stored in Ivakhnenko coefficients. In this paper, the PNN model has been developed using the plasma enhanced chemical vapor deposition (PECVD) experimental data. To characterize the PECVD process using PNN, SiO$_2$films deposited under varying conditions were analyzed using fractional factorial experimental design with three center points. Parameters varied in these experiments included substrate temperature, pressure, RF power, silane flow rate and nitrous oxide flow rate. Approximately five microns of SiO$_2$were deposited on (100) silicon wafers in a Plasma-Therm 700 series PECVD system at 13.56 MHz.

• Journal of The Korean Dental Society of Anesthesiology
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• v.11 no.2
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• pp.133-140
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• 2011

Background: Dental treatment under outpatient general anesthesia is an option for disabled person, children and dentally disabled person who have the difficulty of cooperating voluntary with dental care. The aim of this study was to access the patients who had dental management under general anesthesia at Chungnam dental clinic for the disabled. Methods: This survey is consisted of 114 severely disabled and dentally disabled person who undergone dental treatment under general anesthesia from January to June 2011. Data were collected by individual dental and anesthesia records. Results: Of the 114 patients studies, the 45 patients was the dentally disabled and the 69 patients was the severely disabled. Rate of dental treatment among male patients was higher than among female patients. The dentally disabled was an similar age distribution. In the severly disabled, above 13-year-old was higher than below 12-year-old. The most popular induction method of general anesthesia was sevoflurane inhalation after induced sedative effect of nitrous oxide inhalation. The severly disabled who had definitely negative behavior was applied inhalation of high concentration sevoflurane. Conclusions: Chungnam Dental clinic for the disabled provide dental management for the disabled and the dentally disabled.

• Journal of Climate Change Research
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• v.8 no.3
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• pp.247-255
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• 2017

In this study, GHG inventory on 17 local government between 2005 and 2014 is build up using 'GHG emission estimation guideline (2016. 2) for local government' developed and distributed by KECO. This covers all the sectors should be included in national GHG inventory, which are energy, industrial process, agriculture, AFOLU, and waste. In addition, six GHGs, carbon dioxide, metane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, sulphur hexafluoride declared in Kyoto protocol are estimated to reflect utmost precision. Indirect esissions, such as electricity, heat and waste generation are separately estimated as well as direct emissions to help local government to establish substantial and implementable reduction measures of GHGs.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.3
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• pp.112-118
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• 2019

The development of an underwater rocket propulsion system was described in this paper. Throttle able liquid propellant and hybrid rocket propulsion systems were selected for underwater propulsion. A subscale liquid rocket combustion chamber and it's portable stand were developed and their applicability was examined. 1.5-ton.f and 1.8-ton.f hybrid rockets were developed for underwater applications. The test results indicated that the 18-ton.f hybrid rocket fully complies to the performance and underwater cruise stability requirements; thus, its development was concluded to be successfully complete.

• Journal of Yeungnam Medical Science
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• v.36 no.1
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• pp.50-53
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• 2019

Awareness during general anesthesia occurs in approximately 0.1-0.2% of cases; nevertheless, particular attention is required because it can lead to critical complications including insomnia, depression, anxiety, and post-traumatic stress disorder. To prevent these complications, bispectral index (BIS) and end-tidal anesthetic gas (ETAG) concentration monitoring are commonly used to examine patient consciousness during surgery. In the present case, an 80-year-old man was scheduled for total gastrectomy. Anesthesia was maintained using desflurane 4.0-5.0% vol, oxygen, and nitrous oxide. The authors simultaneously monitored BIS, which was maintained between 37 and 43, and ETAG, which was maintained between 0.9 and 1.2 minimum alveolar concentration (MAC). After the operation, however, the authors were surprised to learn that the patient complained of awareness during anesthesia. Although BIS and ETAG concentration monitoring are useful in preventing awareness during anesthesia, they cannot be completely trusted. Even though BIS was maintained at approximately 40 and ETAG at 0.7-1.3 MAC, awareness during anesthesia occurred.

• Journal of Soil and Groundwater Environment
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• v.27 no.3
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• pp.41-49
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• 2022

This study utilized citric acid as a floating agent in biological denitrification process and assessed its role under different carbon supplying conditions. Several microcosm tests including citric acid active (CAA), precipitating tablet release active (PTRA) and floating tablet release active (FTRA) were conducted to evaluate nitrate denitrification efficacy. In CAA reactors, nitrate removal was accompanied by the formation of denitrification by-products such as nitrite and nitrous oxide, with the extent of nitrate removal being proportional to citric acid concentration. These results suggest that citric acid induced heterotrophic biological denitrification. PTRA reactor that incorporated CAA and the same electron donor showed a similar denitrification efficiency to CAA reactor. FTRA reactor, which contained the same amount of fumarate as PTRA, enhanced denitrification by 7% as compared to the PTRA reactor. The overall results of this work indicate that surplus citric acid can be efficiently utilized in heterotrophic denitrification.

• Journal of Animal Science and Technology
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• v.65 no.2
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• pp.459-472
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• 2023

Korea is currently developing country-specific emission factors to support the 2050 zero-carbon campaign. Dairy cattle represent one of the largest livestock industries in Korea, and the industry is estimated to continue increasing because of an increase in milk demand. However, country-specific emission factors for dairy cattle are currently only available for calculating methane (CH₄) emissions from enteric fermentation. Two experiments were conducted to evaluate CH₄ and nitrous oxide (N₂O) fluxes from sawdust-bedded barn in dairy cow and steer, as well as dairy cattle manure composting lots. The greenhouse gas (GHG) fluxes were quantified using the open-chamber method and gas chromatography. CH₄ fluxes from steer, dairy cow, and manure compost were 27.88 ± 5.84, 36.12 ± 10.85, and 259.44 ± 61.78 ㎍/head/s, respectively. N₂O fluxes from steer, dairy cow, and manure compost were 14.04 ± 1.27, 4.11 ± 1.57, and 3.97 ± 1.08 ㎍/head/s, respectively. The result of this study can be used to construct country-specific data for GHG emissions from manure management. Thus, the application of mitigation strategies can be prioritized based on the GHG profile and targeted source.

• Journal of Environmental Science International
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• v.31 no.2
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• pp.195-213
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• 2022

This research summarizes the generating factors of greenhouse gas (carbon dioxide, methane, nitrous oxide) in hydropower dams and related domestic/foreign researches. Microorganisms and eutrophication are the main factors in greenhouse gases in hydropower dam reservoirs. The greenhouse gas emission from the hydropower dam is affected by meteorological factors and dam operation periods, and greenhouse gases are also emitted from the outlets. The fluxes of greenhouse gas emission from the hydropower dams were -926~180,806 mg CO₂ m^-2d^-1, -0.19~3800 mg CH₄ m^-2d^-1, and 0.01~16.1 mg N₂O m^-2d^-1. In South Korea, the study on the greenhouse gas emission from Korean hydropower dams has been rarely, and therefore it is inquired. This research suggested the methods on the greenhouse gas emission from Korean hydropower dams and flux calculation.

• Journal of the korean academy of Pediatric Dentistry
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• v.51 no.2
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• pp.109-131
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• 2024

This review aims to examine safety concerns in pediatric dental care and underscore the need for comprehensive patient safety initiatives within the Korean Academy of Pediatric Dentistry. Drawing insights from the prevailing patient safety policies of the American Academy of Pediatric Dentistry, case reports, and systematic reviews, this review elucidates issues such as dental fires during sedation, ocular complications from local anesthesia, and surgical emphysema. This review highlights the significance of safety toolkits encompassing infection control, medical error reduction, dental unit waterline infection, and nitrous oxide safety in pediatric dental settings, underscoring the need to foster a safety culture. Furthermore, this study explores the curriculum for pediatric dentistry residency programs, emphasizing concepts such as high-reliability organizations and mortality and morbidity conferences. The study suggests the need for initiatives to enhance patient safety, including establishing safety committees, expanding reporting systems, policy development, and supporting research related to patient safety. In conclusion, this study underlines key messages, emphasizing the utmost priority of patient safety, acknowledging the inevitability of human error, promoting effective communication, and cultivating a patient safety culture. These principles are vital for advancing patient safety in pediatric dental care and improving outcomes among pediatric patients.