• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 추계학술대회 논문집
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• pp.142-144
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• 2008

• 항공우주정책ㆍ법학회지
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• 제13권
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• pp.167-206
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• 2001

• 한국양식학회지
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• 제14권1호
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• pp.57-64
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• 2001

In Paralichthys olivaceus and Nibea japonica, response to live air (5hr) or ship (25hr) transportation was assessed, by determining the levels of plasma cortisol, glucose, lactic acid and osmolality, as well as hematological parameters namely hematocrit (Ht), red blood cell (RBC) count, hemoglobin (Hb), corpuscular volume (MCV), corpuscular hemoglobin (MCH) and corpuscular hemoglobin concentration (MCHC). In the experimental series I, the olive flounder was subjected to stress or no stress for 1hr, prior to its air transportation for 5hr. The stress suffered by the flounder prior to air transportation resulted in significant reduction in Ht, but increases in MCH and MCHC. Air transportation led to increases in MCV and MCH in both the stressed and non stressed groups. In the non stressed group it led to significant increase in Ht but decrease in MCHC. In the stressed group, the air transportation led to significant increases in osmolality and plasma cortisol from 5 to 38.5ng/$m\ell$. Non stressed groups did not show significant differences in this before and after transportation. In the experiment II, the red blood cell (RBC) count ranged from 2.5$\times$10$^{6}$ /${mu}ell$ to 2.7$\times$10$^{6}$ /${mu}ell$ in the flounder and 1.9$\times$10$^{6}$ /${mu}ell$ to 2.1$\times$10$^{6}$ /${mu}ell$ in the croaker during the pre- and post-transportation, respectively. In the croaker the shipping led to significant increase in plasma cortisol from 26 to 35ng/$m\ell$ but decrease in glucose from 91.0 to 26.4mg/㎗. For glucose the reverse (39.0 to 51.0mg/㎗) was true for the flounder.

• 한국대기환경학회지
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• 제2권2호
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• pp.31-40
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• 1986

Motor vehicle related air pollution has become more serious because of rapid increase of number of cars, specially in the urban area. The increase trend seems to be accelerated, however, the fact is that road conditions, parking facilities and traffic control systems are far behind coping with this situation. In spite of the lack of related basic data, urban transportation planning (UPT) and air pollution dispersion models were applied to predict air pollution level. In standard UPT model, trip generation, distribution, modal split and network assignment were estimated by experimental equations and appropriate models. The air pollution level in the central business area was believed to be higher and it will increase continuously due to the increase of traffic demand. To meet this situation, air pollution problem should be considered as a part of integrated plannings of urban plans or transportation plans as well as more stringent motor vehicle emission standards, have to be enforced.

• 한국환경보건학회지
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• 제20권1호
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• pp.28-38
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• 1994

The objective of this study were to measure concentrations of indoor pollutants in public transportation systems to provide importance of indoor air quality in transportation systems to policy makers. Indoor air quality of the pollutants (CO, CO$_2$, PM-10) and environmental sources (temperature, humidity) were measured at subway, seat-type bus, and city-type bus in the Seoul area from April to September 1992. The same pollutants and environmental sources were also measured at selected bus stops and subway stations during October 1991-September 1992. The mean concentrations of indoor pollutants in the public transportation systems were showed 115.5 $\mu$g/m$^3$ in PM-10, 6.8 ppm in CO, and 2167.9 ppm in CO$_2$, respectively. The mean values of PM-10 and CO showed below the U.S. 24 hour standard value of PM-10 and the Korea ambient CO standard, while the mean concentrations of CO$_2$ exceeded the Korea CO$_2$ standard. The highest levels of indoor concentration at public transportation systems were PM-10 of 134.6 $\mu$g/m$^3$ in the subway, CO of 8.9 ppm in the city-type bus, CO$_2$ of 2,511.1ppm in seat-type bus, respectively. The results showed that indoor air quality in bus and subway seemed likely to be affected by number of passengers and outdoor air infiltrated from exhausted gases of automobiles.

• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3682-3694
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• 2022

The expansion of a country's ecological footprint generates resources for economic development. China's import bill and carbon footprint can be reduced by investing in green transportation and energy technologies. A sustainable environment depends on the cessation of climate change; the current study investigates nuclear energy efficiency, economic complexity, air transportation, and industrial improvement for reducing environmental footprint. Using data spanning the years 1983-2016, the dynamic autoregressive distributed lag simulation method has demonstrated the short- and long-term variability in the impact of regressors on the ecological footprint. The study findings revealed that economic complexity in China had been found to have a statistically significant impact on the country's ecological footprint. Moreover, the industrial improvement process is helpful for the ecological footprint in China. In the short term, air travel has a negative impact on the ecological footprint, but this effect diminishes over time. Additionally, energy innovation is negative and substantial both in the short and long run, thus demonstrating its positive role in reducing the ecological footprint. Policy implications can be extracted from a wide range of issues, including economic complexity, industrial improvement, air transportation, energy innovation, and ecological impact to achieve sustainable goals.

• 대한기계학회논문집B
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• 제30권4호
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• pp.306-313
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• 2006

Automated material handling system is being used as a method to reduce manufacturing cost in the semiconductor and flat panel displays (FPDs) manufacturing process. Those are considering switch-over from the traditional cassette system to single-substrate transfer system to reduce raw materials of stocks in the processing line. In the present study, the wafer transportation speed has been evaluated by numerical and experimental method for three propulsion nozzle array (face, front, rear) in an air levitation system. Test facility for 300 mm wafer was equipped with two control tracks and a transfer track of 1,500mm length. The diameter of propulsion nozzle is 0.8mm and air velocity of wafer propulsion is $50\sim150m/s$. We found that the experimental results of the wafer transportation speed were well agreed with the numerical ones. Namely, the predicted values of the maximum wafer transportation speed are higher than those values of experimental data by 16% and the numerical result of the mean wafer transportation speed is higher than the experimental result within 20%.

• 한국항공운항학회지
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• 제32권2호
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• pp.37-47
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• 2024

This paper examines the unique transportation challenges posed by Nepal's diverse and rugged terrain, which significantly hampers socio-economic development due to its negative impact on infrastructure, trade, and accessibility. Despite ongoing efforts to enhance road and traditional air transport systems, Nepal's geographic and environmental conditions continue to obstruct efficient connectivity, particularly in rural and remote areas. This study proposes Advanced Air Mobility (AAM) as a transformative solution, leveraging recent technological advancements in unmanned aerial vehicles (UAVs) and electric vertical takeoff and landing (eVTOL) aircraft. By conducting a comprehensive analysis of Nepal's current transportation infrastructure and the feasibility of AAM implementation, the paper highlights the potential benefits of AAM, including improved accessibility, economic growth, and environmental sustainability. Furthermore, it addresses the anticipated challenges and regulatory considerations necessary for integrating AAM into Nepal's transportation network. Through a multidisciplinary approach, this research aims to contribute to the discourse on overcoming transportation barriers in mountainous regions, offering policy recommendations and identifying areas for future study to facilitate the adoption of AAM in Nepal and similar contexts worldwide.

• 기술사
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• 제32권5호
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• pp.118-125
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• 1999

Air pollutant emissions from airplane engines are estimated about 2 to 4 % of mobile source of USA and European countries which is not a large portion of current air pollution. But the passengers and airfreights are continuously increasing 5 to 7% annually and potential demands of air transportation services come to present, it could effect air pollutant emissions of USA will increase within 15 years. In case of our country, there has been continuous increase of air transportation service due to considerable economic growth in recent years and increase of air pollutant emissions of major international airports has followed. Rapid increase of air transportation due to launching of Inchon International Airport could effect air pollution dominantly. By this circumstance environmental specialist as well as mass communication raised necessity of air pollutant emission regulation from airplane engines. It is estimated that air pollutant emissions from airplane engines in our country is 2.7% of automobile sources, 10,809 ton, which is the same level as USA and European countries. It is increased by 12,2% compared to air pollutant emissions during 1996 and it will be increased more than a half of current air pollutant emission within 15 years due to our country's economic condition. Therefore implementation of airplane engine emissions regulation as well as test standards and accumulation of technology about characteristics of airplane engine emission and reduction method are needed. And continuous estimation of air pollutant emission from airplane engines and monitoring of increment as well as development of countermeasures by long term are necessary.

• 환경위생공학
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• 제10권3호
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• pp.124-130
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• 1995

Air pollution problem by air craft was reviewed from emission gas components from air craft and pollutants amount generated in airport with the compareness of domestic transportation data by airplane and foreign data. It is reported that concentration of emission gas from air craft is lower than that of pollutants from automobile and factory. But transportation frequency is increasing rapidly in Korea. It is recommended that concerns should be taken on long- term of counterplan device about it.