• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.415-422
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• 2006

This study aims for suggesting an idea to plan the expansion of consuming environmentally friendly chestnuts by statistically analyzing the types and intentions for consumer's purchase of environmentally friendly point of production and export side. For this, the survey was performed on 650 housewives living in Seoul, new metropolitan cities such as Ilsan, Bundang, where is the central place of main consumption. As a result, it is more effective to plan the expansion of consumption as the activity of consumption promotion for environmentally friendly chestnut focused on specific target such as 3~4 members of family and 30~40's age of young housewives having with the academic background of above university graduate, large income of average monthly payment with over 4.5 million won and consumers who have experience to purchase environmentally friendly forest products. In order to achieve this goal, it is require to secure the stabilized dealer for the environmentally friendly forest products as well as to establish the appropriate price reflected by the value and quality of environmentally friendly chestnut which the consumers recognize. It is estimated that this price can be decided on the basis of willingness to pay for the environmentally friendly chestnut from the index which comes from the integrated and concentrated consumers' expectation as this study surveyed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.608-613
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• 2019

NOx (Nitrogen oxide) in the exhaust gas from vehicle engines is considered one of the most harmful substances in air pollution problems. NOx is made when combustion occurs under high temperature conditions and EGR (exhaust gas recirculation) is normally used to lower the combustion temperature. As the EGR ratio increases, the NOx level becomes low, but a high EGR ratio makes the combustion unstable and causes further air pollution problems, such as CO and unburned hydrocarbon level increase. This study showed that fuel droplets could move more freely by the radiation of sonic wave for the stable combustion. In addition, the engine performance improved with increasing EGR ratio. As a basic study, the effect of sonic wave radiation on the velocity of fuel droplets was studied using CFD software. The results showed that the velocity of small droplets increased more under high frequency sonic wave conditions and the velocity of the large droplets increased at low frequency sonic wave conditions. In addition, an engine analysis model was used to study the effects of the increased combustion stability. These results showed that a 15% increase in EGR ratio in combustion resulted in a 45% decrease in NOx and a 10% increase in thermal efficiency.

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.84-106
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• 1994

Hyperbaric oxygen (HBO) therapy for carbon monoxide (CO) poisoning eventually inducing the hypoxia-reoxygenation condition, may produce oxygen free radicals, which forms 8-hydroxydeoxyguanosine (8-OH-dG) by attacking C-8 position of deoxyguanosine (dG) in DNA. Effects of oxygen partial pressure or duration of HBO therapy with or without CO poisoning on the tissue 8-OH-dG formation were investigated. Male Sprague-Dawley rats were grouped and exposed to air (control group), 4000 ppm of CO for 10 to 30 minutes (CO only group), air for 30 minutes after 30 minute exposure to 4000 ppm of CO(CO-air exposure group), HBO after 30 minute exposure to 4000 ppm of CO(CO-HBO group), or HBO therapy fo. $10{\sim}120$ minutes(HBO only group). The 8-OH-4G concentrations in the brain and the lung tissues were measured with high performance liquid chromatography and electrochemical detector (ECD). Average concentrations of the 8-OH-dG of each group were statistically compared. In the brain tissues, 8-OH-dG concentrations of the CO only group, the CO-air exposure group, and the CO-HBO group did not significantly differ from those of the control group. Similar insignificance was also found between the CO-HBO group and the HBO only groups. No appreciable dose-response relationship was observed between the 8-OH-dG concentration and the oxygen partial pressure or the duration of HBO. However, the 8-OH-dG concentrations of the 30 minute CO only group were higher than those of the CO-air exposure group (p-value<0.05). In the lung tissues, there were no significant differences between the 8-OH-dG concentrations of the control group and those of the CO only group, the CO-air exposure group, and the CO-HBO group. However, mean 8-OH-dG concentration of the CO-air exposure group was significantly higher than that of the CO only group under the same CO exposure condition(p-value<0.05). With the duration of CO exposure, the 8-OH-dG concentrations of the lung tissues decreased significantly (p-value<0.05). The concentrations of 8-OH-dG in the lung tissues proportionally increased with the duration of HBO, but no such relation was observed with the oxygen partial pressure. These results suggest that the brain may be more resistant to oxygen free radicals as compared with the lungs, and that oxygen toxicity following HBO may be affected by factors other than oxygen free radicals.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.385-390
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• 2013

The effect of tuna extracts on the production of nitric oxide (NO) and cytokines including interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and interferon-${\gamma}$ (IFN-${\gamma}$), was investigated. All extracts and fractions from tuna significantly reduced NO production induced by lipopolysaccharide (LPS). The acetone+methylene chloride (A+M) extract, n-hexane and 85% aqueous methanol (MeOH) fractions had stronger inhibitory effects among them. The 85% aqueous MeOH fraction at a 10-${\mu}g$ concentration significantly decreased LPS-induced IL-6 and TNF-${\alpha}$ productions at 6 h of incubation. In the case of LPS-induced IFN-${\gamma}$ production, the 85% aqueous MeOH fraction at a 3-${\mu}g$ concentration showed significantly higher levels at 48 h of incubation. These results show that the 85% aqueous MeOH fraction inhibited the production of NO and pro-inflammatory cytokines (IL-6, TNF-${\alpha}$), suggesting that this fraction acts as a potent immunomodulator.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.101-109
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• 2007

Two variations of toll roads exist: mainline toll plazas and entry/exit tolls. On a mainline toll system(open toll scheme), all vehicles stop at various locations along the highway to pay a toll. While this may save money from the lack of need to construct tolls at every exit, it can cause lots of traffic congestion, and drivers could evade tolls by going around them. With entry/exit tolls, vehicles collect a ticket when entering the highway, which displays the fares it will pay when it exits, increasing in cost for distance travelled. Upon exit, the driver will pay the amount listed for the given exit. The pressures on the Seoul ring roadway network have been changing over time. In the past, the emphasis was on mobility and maintenance of the road network to provide an efficient transportation network, but recently, road use has outstripped the network's ability to extend and expand the road network and hence the policy emphasis has moved towards reducing free riders rather than mitigating its effects. In addition to this pressure is an incidental pressure, which argues that provision of free ride segments generates further traffic in isolation of other factors. This paper is examining policies to reduce the burden of traffic congestion in Seoul ring roadway which is used open toll scheme for decades. One key mechanism to achieve this policy aim is automatic charging mechanism on freeway, but if a nation-wide electronic toll collection is to be implemented successfully, there are a number of prerequisites which must be place.

• Land and Housing Review
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• v.5 no.4
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• pp.235-246
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• 2014

In the late 1980s, 5 new towns such as Bundang, Ilsan, Pyeongchon, Sanborn, Jungdong were constructed to solve housing problems and to disperse functions concentrated within Seoul. As the city got matured, it began to appear the initial signs of urban problems such as aging of high rise-density apartment sites, traffic congestion, lack of parking spaces and aging of infrastructure. Therefore, in order to cope with urban problems, it is very important to apprehend the process of urban growth, its change and the feature of physical/human elements. So, the purpose of this thesis is to analyze the changes in housing and population characteristics for past 20 years by use of Census data from 1995 to 2010. First, the new town's goal of population and housing plan at the time of construction was analyzed how it was achieved, and it is close to the performance of the goal. And the trend of changes in the population and household characteristics was analyzed by every five year's data. As the result of analysis, it shows socio-demographic changes such as aged and elderly population growth, rapid increase in one generation's household and single person household, highly educated city, monthly rent household's increase and charter household's reduction. Results of this analysis can be utilized to aforethought management of new towns. But it is required more sustained and systematic urban monitoring and data analysis because the one-off analysis of the city's characteristics alone is difficult enough to grasp them.

• Fire Science and Engineering
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• v.30 no.5
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• pp.93-99
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• 2016

This study tested the combustion characteristics of veneer specimens coated with four kinds of ammonium salts. Each veneer specimen was coated three times with 20 wt.% ammonium salt solutions at room temperature. After drying, the combustion characteristics of the specimens coated with chemicals, were investigated using the cone calorimeter (ISO 5660-1, 2). The specimens coated with monoammonium phosphate (MAPP) and, diammonium phosphate (DMPP) showed a 6.7% and, 10.0%, lower mean heat release rate ($HRR_{mean}$), respectively, than that of the uncoated specimen. On the other hand, the specimens coated with MAPP showed a 15.7% higher $CO_{peak}$ production rate and the specimens coated with DAPP showed by 8.2% lower rate than that of the uncoated specimen. The veneer coated with ammonium sulfate (AMSF) and DAPP showed a 9.6% and 33.3% lower the peak smoke production rate ($SPR_{peak}$) than that of the uncoated specimen. In addition, the time to the peak smoke extinction area ($SEA_{peak}$) was delayed by 38.4% in the specimens coated with DAPP than the uncoated specimen. Therefore, DAPP inhibited the combustion properties of the veneer and showed a tendency to reduce smoke production.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.277-281
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• 2012

This work is concerned with a plan for preventing accidents of CO gas leak from gas boilers, involving the enforcement of installations of both CO alarm system and condensing boilers, and financial support of government grants. If amongst 1,460,000 beneficiaries of basic livelihood security, one million households in use of gas boilers receive 3-year support of 200,000 won, the difference of prices between common and condensing boilers, the government grants would be 2,000 billion won. If 3 million common householders are in 3-year support of 100,000 won, government grants would be 3,000 billion won. Therefore, 3-year grand total of government grants would be 5,000 billion won. Finance for government grants can be purveyed from energy saving; yearly 2,000 billion won of energy saving by enforcing to replace one million existing boilers with condensing boilers, leading to 2 trillion won of energy saving for 10 years. In this way, 6,000 billion won of 3-year grand total of government grants for CO alarm system and condensing boilers can be purveyed. The rest amount would be fundraised for energy savings. We claim that our proposal can make an achievement of more than 50% reduction of CO leak accidents during 10 years.

• Spatial Information Research
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• v.18 no.2
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• pp.67-75
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• 2010

When people are shopping at a large shopping mall, they usually become to go around many stores for looking for better products and comparing them. In this paper, we design and implement a purchasing activity support system based on an Ambient Service Model that provides relevant stores information on map interface hierarchically through user contexts based search, to support such user's purchasing activities with the help of relevant information. In this system, users can search for relevant stores information through the system by Ambient Query which is created by their location and stores information with a mobile device. Then, users obtain relevant stores information provided in the form of hierarchy of keywords as a highly condensed summary and easily figure out the locations of the stores on a map interface. Moreover, users search additional other kinds of relevant stores information over the hierarchy of keywords. Eventually, users can obtain relevant stores information intuitively and conveniently without complex search processes. We implemented this system by integrating the subordinate technologies such as RFID, map-based, location-based and ontology technology. We also performed experiments on a well-known shopping region (Ilsan Lapesta shopping mall, Goyang-city Gyeonggi-do, Korea). Finally, we also confirmed that users' shopping activities were significantly improved by utility the present system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.17-25
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• 2016

In this study, the air quality of underground and overground railway stations was evaluated focusing on the degree of influence of the outside air quality. The measured components were particulate matter ($PM_{10}$), carbon dioxide ($CO_2$), carbon monoxide (CO), nitrogen dioxide ($NO_2$), formaldehyde (HCHO), ozone ($O_3$), total airborne bacteria (TAB), total volatile organic carbon (TVOC), and Radon (Rn), which are included in the maintenance standards and recommended standards of the Indoor Air Quality Management Act. Also, the indoor/outdoor concentration ratios of $PM_{10}$, $NO_2$, and $O_3$ were calculated to estimate the influence of the outdoor air quality. The concentrations of $PM_{10}$ HCHO, TVOC, $NO_2$, and Rn in the underground stations were found to be higher than those in the overground stations. These results indicate that the (present) generation of contaminants are caused by the indoor source of the underground station. The ozone concentration of the overground stations was higher than that of the underground stations, which indicates that the outdoor ozone concentration influenced that of the overground stations directly. Thus, methods of improving the IAQ should take into consideration the types of contamination.