• Journal of the Korean Society of Combustion
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• v.13 no.2
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• pp.23-32
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• 2008

Gasification characteristics in the fluidized bed reactor are essential for the design of a gasification furnace to optimize the operation condition. Moisture content of the solid fuel is one of the important factors to influence directly the gasification characteristics. So it is necessary to investigate the effect of moisture content of solid fuel in partial oxidation condition. Gasification characteristics are investigated with results from thermogravimetric analyzer and lab-scale fluidized bed reactor for wood and RDF samples along with changing moisture contents. Additionally lab-scale fluidized bed reactor was run continuously and gas concentrations at the exit were measured. It is observed that the rate of reaction in partial oxidation condition is between the results from the combustion environment and from the inert condition. Moisture content in a particle slows down the heating rate of a particle. So, reaction is delayed by the moisture content. However, RDF samples those are easy to break-up don't show the effect of moisture content. The result of continuous operation condition shows that proper moisture content promotes gasification because steam from the particles helps gasification of the solid fuel. A simulation to predict the syn-gas composition was conducted by the Aspen Plus process simulator. The cold gas efficiency of the experiment was compared with results from the simulation.

• Fire Science and Engineering
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• v.13 no.2
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• pp.12-17
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• 1999

We intended to investigate combustion properties of rice bran dust. Combustion properties of h rice bran dust according to size distribution and amount were measured as temperature v variation with time using spontaneous ignition apparatus. Moreover, combustion properties w with blowing or without blowing condition were checked in order to investigate combustion p properties in spontaneous ignition apparatus according to flow condition of air. A As the mass and size of rice bran dust was increased, i띠ti외 smoldering temperature was l lowered. All of combustion forms were smoldering combustion. Initial smold얹ing temperature w was slightly lower with blowing condition than without blowing condition in spontaneous i ignition apparatus, which condition made heating value high.

• Journal of Acupuncture Research
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• v.21 no.4
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• pp.31-51
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• 2004

Objective: The propose of this study is to investigate the characteristics of combustion in indirect moxibustion with garlic. Methods: We observed the characteristics of combustion by the variations of the thickness(3mm, 4mm, 5mm) of a slice for indirect moxibustion with garlic and mass(80mg, 100mg, 120mg) of moxa cone and existence of holes. The temperature of indirect moxibustion for garlic insulation with holes was higher than temperature of indirect moxibustion for garlic insulation without holes. Combustions time in the preheating period is about 1 minute, it varies by the existence of holes, the thickness of a slice for indirect moxibustion with garlic, and the density of moxa cone. Results: Maximum temperature of heating period was $38.7{\sim}46.2^{\circ}C$, combustion time in the heating period was 118~164sec and maximum ascending temperature gradient was $0.102{\sim}0.264^{\circ}C/sec$. Retaining period was shorter than heating period and stimulus of heating retains more, because it is higher than body temperature. By this report, indirect moxibustion with garlic is more effective with holes and the appropriate thickness of a slice for indirect moxibustion with garlic is 3.5~4mm. It is appropriate that the diameter of moxa cone is 8mm and height of that is 10mm. With this condition, effective combustion period is 120sec, maximum temperature is $42{\sim}44^{\circ}C$, maximum ascending temperature gradient is $0.14{\sim}0.16^{\circ}C/sec$. It is necessary to study clinical correlations for more accurate quantitative standard.

• Journal of Environmental Impact Assessment
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• v.12 no.4
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• pp.281-290
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• 2003

The influence of land-use type on surrounding temperature was studied the relationships between land-use types and the air condition analyzing AWS (Automatic Weather Station) data of Seoul from KMA (Korea Meteorological Administration). The distribution of air temperature by land-use type has been influenced by the different heating and cooling rates. The difference of heating rates depending on the land-use type was largest at 2~3hours after sunrise and the difference of cooling rates was largest from 2hours before sunset to 2hours after sunset with its maximum at sunset. The difference of cooling rates is greatest in a clear and calm weather situation and the large difference in cooling rates between the green areas and built-up area is up to $1.5^{\circ}C/h$. By season, the difference of cooling rates is largest in fall and in turn spring, winter and summer. In a cloudy or rainy day, the difference in heating and cooling rates on land-use type is not distinct but the tendency is similar to a clear day. In all seasons, the rate of difference occurrence of the daily range of temperature between the green areas and built-up area was large, especially fall. In a fall with a clear and calm day, the magnitude of the daily range of temperature between the green areas and built-up area was largest.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.1
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• pp.43-48
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• 2017

In recent years, the demand for ships and offshore platforms that can navigate and operate through the Arctic Ocean has been rapidly increasing due to global warming and large reservoirs of oil and natural gas in the area. Winterization design is one of the key issues to consider in the robust structural safety design and building of ships that operate in the Arctic and Sub-Arctic regions. However, international regulations for winterization design in Arctic condition regulated that only those ships and offshore platforms with a Polar Class designation and/or an alternative standard. In order to cope with the rising demand for operating in the Arctic region, existing and new Arctic vessels with a Polar Class designation are lacking to cover for adequate winterization design with HSE philosophy. Existing ships and offshore platform was not designed based on reliable data based on numerical and experiment studies. There are only designed as a performance and functional purposes. It is very important to obtain of reliable data and provide of design guidance of the anti-icing structures by taking the effects of low temperature into consideration. Therefore, the main objective of this paper reconsiders anti-icing design of aluminum helideck using the heating cable. To evaluate of reliable data and recommend of anti-icing design method, various types of analysis and methods can be applied in general. In the present study, finite element method carried out the thermal analysis with cold chamber testing for performance and capacity of heating cables.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.66-71
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• 2009

To reduce the building energy consumption, the major advanced nations are conducting actively many researches on so called a "self-sufficient building(or other words zero energy building)" which can support its required energy by itself. Given this background, KIER(Korea Institute of Energy Research) built full size test-bed of the zero energy solar house in early 2002, and has studied on the self-sufficient heating load up to now. We analyse the sensitivity between the heating load and the solar radiation gain according to the change the effective transmittance of windows. The authors classified 9 cases by solar transmittance of glass. The results demonstrate the solar radiation amount is 0.466 MWh from the eastern zone of Fl.,1(the first floor), 0.332 MWh from Fl.,2(the second floor), 1.194 MWh form the southern zone of F1., and 0.822 MWh from the southern zone of Fl.,2 on the case 1(each cases are classified by window types). On the case 9, the solar radiation amount is 3.127 MWh, 2.662 MWh, 8.799 MWh and 6.078 MWh from the same condition. For the Fl.,1, the amount of Heat Load that is saved per year ranged 10.5 to 48 %, and the reduction was anywhere from 0.2 to 17.9% for Fl.,2

• KIEAE Journal
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• v.4 no.3
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• pp.203-210
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• 2004

This dissertation identifies and investigates the possible control modes of hybrid ventilation system in applying to general apartments. It evaluates range of hybrid ventilation control modes in terms of indoor air quality, thermal comfort, and energy consumption in a living room and a kitchen of the $1000m^2$ apartment. The TRNSYS simulation program was used for evaluating the following four ventilation types : A ventilation mode relying on only infiltration for supplying air, A natural ventilation mode considering with weather condition, A hybrid ventilation (natural + mechanical ventilation) mode allowing minimum ventilation with no heat exchange, and a hybrid ventilation mode with heat exchange. This study shows the following results. As temperature being controlled by heating cooling equipments, there is without significant difference in thermal performance among ventilation types. Regarding Indoor Air quality, Indoor air contamination level of the hybrid ventilation case consistently keep the lower levels. The hybrid ventilation modes consume more energy by a 49% as compared to the A ventilation mode relying on only infiltration for supplying air. It is caused by the continuous ventilation for keeping good indoor air quality; the increase of energy consumption can be attributable to the increase of the heating energy. Therefore, the heat exchange between indoor and outdoor air is required during heating season in severe weather conditions. During the cooling seasons, Introducing natural ventilation can achieve energy saving by 40 ~ 45%. Thus, it can be an effective strategies for energy saving. Based on these results, a hybrid ventilation system can be suggested as an effective ventilation strategy for archiving high level of indoor air quality, thermal comfort, and energy consumption.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.632-636
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• 1993

Gel strength of fish protein at various processing conditions such as heating temperature, heating time and salt content was determined by using compressive stress and residual delay time of ultrasonic wave. The compressive stress, interpreted as indicating the relative gel strength, was increased with increasing the heating temperature and heating time, and with decreasing the salt content, while the delay time of ultrasonic wave reduced, indicating that the gel strength and the delay time are inverse proportion. The result of the multiple regression analysis with factorial design showed that the model equation consisted with delay time and processing condition variables gave the good prediction of the gel compressive stress which was coincided with compressive stress measured.

• Resources Recycling
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• v.23 no.5
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• pp.28-35
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• 2014

The basic properties of cow and chicken manure such as proximate analysis and element analysis were estimated and the comparison to energy characteristics of carbonization residue between cow and chicken manure was evaluated. The optimum carbonization condition of cow and chicken manure was decided by total heating value of carbonization residue which was expressed by multiplying low heating value by yield. The optimum carbonization conditions for carbonization time and temperature can be decided by 15 min, and $350^{\circ}C$ for chicken manure, and 20 min, and $300^{\circ}C$ for cow manure. At the optimum carbonization conditions, low heating values for the carbonization residue of cow and chicken manure are evaluated by 4,378kcal/kg, and 3,462kcal/kg, respectively. The residues of cow manure were satisfied with the standard of solid fuel product. However, the residue of chicken should be improved by materials changes to be used as a renewable energy source.

• Journal of Life Science
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• v.14 no.1
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• pp.110-114
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• 2004

The optimized RAPD-PCR conditions, that can be utilized as a basic information for analysis of the gelletic characteristics were developed for genetic analysis of four mulberry varieties, named Milsung, Chungil, Suil, and Hansung using a primer, OPY15 (5'-AGTCGCCCTT-3') from Operon company. We tested several different factors for best PCR condition including concentrations of DNA, primer, Mgclu annealing temperature, number of PCR cycle, and prosence/absence of pre-heating time at the begining of PCR reaction in the $25 \mul$volume. The best RAPD profiles were obtained using 50 ng of DNA, 1 $\mu$M of primer, $1 \mum$of $MgCl_2\;,45^{\circ}C$ of annealing temperature and an absence of pre-heating time. An establishment of the stable and reproducible RAPD-PCR conditions are expected to be useful for the subsequent RAPD-related investigation, such as genetic characterization of the mulberry varieties, re-establishment of phylogenetic relationships and development of new varieties.