• Journal of the Korean Society of Combustion
• /
• v.20 no.4
• /
• pp.19-25
• /
• 2015

An experimental study was conducted to find the effect of a pilot flame on the flammability of inert-gas-diluted methane and propane. The diffusion pilot flame was formed with propane at the innermost nozzle of a concentric triple co-flow burner. The main diffusion flame was formed with nitrogen-diluted methane or propane at the outermost nozzle of the burner. An air flow was located in-between. The results showed that the existence of the pilot flame helped stabilizing the main flame even at the flammability limit concentration of nitrogen-diluted fuel. The co-flow burner generated re-circulation zones and local variation of equivalence ratio depending on the flow rates of the reactants, which are known to help flame stabilization. Hot-wire experiments confirmed that both heating of the reactants and supplying of active chemical species by the pilot flame contributed to stabilization of the main flame. The results of this study would suggest a design concept for an efficient SVRU system that minimizes the emission of unburned hydrocarbon fuel from ship fuel tanks.

• Magazine of the Korean Society of Hazard Mitigation
• /
• v.2 no.4 s.7
• /
• pp.40-47
• /
• 2002

Since it is important to understand the bio-climatic change in Seoul for ecological city planning in the future, this paper gives an overview on bio-climate analysis of urban environments at Seoul. We analyzed its characteristics in recent years using the observations of 24 of Automatic Weather Station (AWS) by Korea Meteorological Administration (KMA). In urbanization, Seoul metropolitan area is densely populated and is concentrated with high buildings. This urban activity changes land covering, which modifies the local circulation of radiation, heat and moisture, precipitation and creating a specific climate. Urban climate is evidently manifested in the phenomena of the increase of the air temperature, called urban heat Island and in addition urban sqall line of heavy rain. Since a city has its different land cover and street structure, these form their own climate character such as climate comfort zone. The thermal fold in urban area such as the heat island is produced by the change of land use and the air pollution that provide the bio-climate change of urban eco-system. The urban wind flow is the most important climate element on dispersion of air pollution, thermal effects and heavy shower. Numerical modeling indicates that the bio-climatic transition of wind wake in urban area and the dispersion of the air pollution by the simulations of the wind variation depend on the urban land cover change. The winds are separately simulated on small and micro-scale at Seoul with two kinds of kinetic model, Witrak and MUKLIMO.

• Journal of Ocean Engineering and Technology
• /
• v.10 no.2
• /
• pp.120-135
• /
• 1996

The characteristics and fluctuations of structures and spatial distributions of thermal fronts and warm eddy in the Southeastern part of the East sea are discussed based on the data collected by the Naval Academy, Korea during Feb. 6-9, May 9-19 and Oct. 12-18, 1995. The thermal fronts existed very often at the sea off the Pohang-Ulsan, The generation of the thermal front is related with the development of the North Korea Cold Current. The warm eddy is located in the central part of the Ulleung basin where the local depth exceeds 1500m. This warm eddy is a major contributor to mass transport in the northern part of the East Sea. It is evident that knowledge of warm eddy is important in understanding the circulation in the western part of the East Sea.

• Journal of the Korean Institute of Educational Facilities
• /
• v.14 no.3
• /
• pp.27-35
• /
• 2007

The purpose of this research is to analyzing the welfare function of the senior citizen with similar type of compounding the school facility, to analyze the problematical point of present condition. And also propose the spatial constitution which the student and the regional senior citizen are easy to utilize on the basis of the result. In a type of educational facility composition, it became clear that a ratio and the inflection order that elderly welfare facilities occupied of vacant class room were low. In other words, in composition of a school facilities, elderly welfare facilities can be said to be an important problem. As a result of having analyzed an existing compound facilities, there was limited interchange of student and a the aged. In addition, there were problems such as learning environment by an intersection of circulation. Therefore, composition of educational facility and elderly welfare facilities is not space composition that is intersection of simple specification function. In other words, a program of the common space which is necessary for the local community formation is necessary. Setting of semi-public area proposes the function of the existing facility and actual condition of spatial use in prerequisite.

• Journal of Life Science
• /
• v.9 no.3
• /
• pp.241-247
• /
• 1999

Antibiotics have been routinely used to control the disease of farm-raised animals in the aquaculture facilities without any criterion based on a pharmacokinetic study. This lack of information on the effective usage of antibiotics would have brought the farmers to use excessive and/or less dosages, causing the advent of drug-resistant bacteria as well as economic loss and possible contamination of the local farming area. Until recently, few studies on a detailed manual for the antibiotic usage including chemotherapy procedure, dosage, and treatment schedule of the aquatic antibiotics have been conducted throughout the world. To the worse, there is no available criterion for optimal usage of aquatic antibiotics to control diseases in aquatic farms in this country because every country has its own aquacultural system. Therefore, based on the previous studies on the usage of the various antibiotics, our studies are to focus on the development of optimal method for the detection of various antibiotics on the fate of antibiotics applied to the fish, including absorption, circulation, and secretion physiology. Pharmacokinetic study were to sep up the optimal detective condition against residual antibiotics of fish by HPLC. The grinding pefloxacin for 15 min is most effective in dissolution test and pharmacokinetic parameters. Pharmacokinetic parameters were satisfactory for 15 min-grinding products and they can be explained as one-compartment model.

• Journal of Environmental Science International
• /
• v.11 no.10
• /
• pp.1045-1054
• /
• 2002

Urban atmospheric conditions are usually settled as warmer, drier and dirtier than those of rural counterpart owing to reduction of green space and water space area heat retention in surfaces such as concrete and asphalt, and abundant fuel consumption. The characteristics of urban climate has become generally known as urban heat island. The purpose of this study is to investigate the temporal and spatial distribution of the heat emission from human activity, which is a main factor causing urban heat island. In this study, the anthropogenic heat fluxes emitted from vehicles and constructions are estimated by computational grid mesh which is divided by 1km $\times$ 1km. The anthropogenic heat flux by grid mesh can be applied to a numerical simulation model of the local circulation model. The constructions are classified into 9 energy-consumption types - hospital, hotel, office, department store, commercial store, school, factory, detached house and flat. The vehicles classified into 4 energy-consumption types - car, taxi, truck and bus. The seasonal mean of anthropogenic heat flux around central Daegu exceeded $50 W/m^2$ in winter. The annual mean anthropogenic heat flux exceeded $20 W/m^2$. The values are nearly equivalent to the anthropogenic heat flux in the suburbs of Tokyo, Japan.

• Korean Institute of Interior Design Journal
• /
• v.16 no.6
• /
• pp.161-171
• /
• 2007

With a rapid expansion of the elderly population, there is a greater demand for the construction of senior complexes. However, due to a land price increase and insufficient financial resources, accommodating such a demand is challenging. Also, as aging progresses, many elderlies tend to be isolated from local community, because of deteriorating health. As a result, constructing senior complexes is becoming an important community project. The construction of senior complexes in Korea has been started since early 2000, so it is still in the beginning stage in Korea. However, in the case of Japan, they have more experience in building such buildings. Therefore, in this study, 49 senior complexes in Japan were analysed, and the following spatial characteristics were derived. 1. By classifying senior complexes largely into a complex type with similar facilities and a complex type with different facilities, 12 types were derived. Depending on the types of facilities, basic sharing rooms and selectively sharing rooms by need are suggested. 2. Depending on 4 characteristics, such as spatial composition, entrance type, circulation form, and complex facility type, 17 types of senior complexes were derived, and the characteristics of each type are presented.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.8
• /
• pp.2436-2448
• /
• 1996

This paper presents the development of three types of network performance manager for IEEE 802.4 token bus networks that are a part of Manufacturing Automation Protocol(MAP). The performance managers attempt to keep the average data latency below a certain level specified for each priority class. All of the three performance managers are based on a set of fuzzy rules incorporating the knowledge on the relationship between data latency and parameters of the priority mechanism. These Fuzzy Network Performance Managers(FNPMs) have been evaluated via discrete event simulation to demonstrate their efficacy.

• Journal of the korean society of oceanography
• /
• v.38 no.2
• /
• pp.60-67
• /
• 2003

Typhoon Rusa passed over the East China Sea and crossed over the Korea Peninsula on August 31, 2002. The core of the typhoon passed directly over a data buoy mooring site at ($127^{\circ}45'E,\;34^{\circ}25'\;N$) and several ARGOS-tracked drifters capable of measuring salinity. Peak hourly mean wind speed reached 28 m/s at the mooring site and wind pattern in the East China Sea changed from southerly wind to northwesterly wind after the typhoon passage. Two or three days before the typhoon tile drifter displacement changed significantly and the region-wide circulation pattern changed from a northeastward current to a westward current one week after the typhoon had passed. The surface water in the East China Sea was cooled to about $4^{\circ}C$ under the typhoon core and a general cooling occurred in most of the East China Sea with the exception of the Chinese coast. The salinity as observed by the drifters in the East China Sea increased about 2 psu but the near-shore water along the Korean coast observed by the mooring was freshened about 3 psu. The freshening of near-shore water was caused by an intrusion of off-shore water rather than local freshening by typhoon precipitation.

• Korean Journal of Remote Sensing
• /
• v.21 no.1
• /
• pp.51-57
• /
• 2005

The currently operating NASA/GFZ Gravity Recovery and Climate Experiment (GRACE) mission is designed to measure small mass changes over a large spatial scale, including the mapping of continental water storage changes and other geophysical signals in the form of monthly temporal gravity field. The European Space Agency's Gravity field and steady state Ocean Circulation Explorer (GOCE) space gravity gradiometer (SGG) mission is anticipated to determine the mean Earth gravity field with an unprecedented geoid accuracy of several cm (rms) with wavelength of 130km or longer. In this paper, we present a summary of present GRACE studies for the recovery of hydrological signals in the Amazon basin using alternative processing and filtering techniques, and local inversion to enhance the temporal and spatial resolutions by two-folds or better. Simulation studies for the potential GRACE detection of slow deformations due to Nazca-South America plate convergence and glacial isostatic adjustment (GIA) signals show that these signals are at present difficult to detect without long-term data averaging and further improvement of GRACE measurement accuracy.