• Journal of Environmental Science International
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• v.8 no.1
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• pp.135-144
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• 1999

Air quality modeling about coastal urban region such as Pusan shoud be consider shipping source emmited from ships anchoraging and running. It has been proved at our previous studies that the ratios of air pollutants emission amount in coastal area to inland are 12.2% for NO$_2$ and 11.7% for $SO_2$ and the air qualify of coastal urban area consierably counts on ships. Also the dispersion pattern of the all pollutants followed local circulation system in this region. Therefore this study has been developed air quality model which can describe the formation, transport, transformation and deposition processes of air pollutants considering shipping source. Currently, restriction for emission amount of ships does not exist, so our study will be useful to set the omission standard and for devising air quality policy in coastal urban region.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.3
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• pp.90-99
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• 2020

The "Low Emission Zone" (LEZ) system restricts entry of vehicles with high air pollutants into city centers. Implementation of the system improves air environment around the world. Since 2012, operating restrictions have been applied to all of Seoul's metropolitan areas and some other metropolitan areas in the state. Beginning in December 2019, entry of 5th class vehicles to the central green transport zone of Seoul has been restricted. In this study we examine the status of operational restrictions in this zone, and predict the amount of traffic reduction expected when numbers of target vehicles are expanded in the future, we use data for each vehicle's emission grade: by region and 'Origin-Destination Traffic Volume'. After estimating the amount of traffic entering Seoul's 25 autonomous districts, by emission class, we propose a target region that may have a significant effect if target areas for automobile operation restrictions expand in the future.

• Journal of Trauma and Injury
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• v.37 no.2
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• pp.106-113
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• 2024

Purpose: Helicopter transport with medical teams has been proven to be effective, with improvements in patient survival rates. This study compared and analyzed the clinical characteristics and treatment outcomes of trauma patients transported by doctor helicopters according to whether patients were transferred after a clinical evaluation or without a clinical evaluation. Methods: This study retrospectively reviewed data from the Korean Trauma Data Bank of trauma patients who arrived at a regional trauma center through doctor helicopters from January 1, 2014, to December 31, 2022. The patients were divided into two groups: doctor helicopter transport before evaluation (DHTBE) and doctor helicopter transport after evaluation (DHTAE). These groups were compared. Results: The study population included 351 cases. At the time of arrival at the trauma center, the systolic blood pressure was significantly lower in the DHTAE group than in the DHTBE group (P=0.018). The Injury Severity Score was significantly higher in the DHTAE group (P<0.001), and the accident to trauma center arrival time was significantly shorter in the DHTBE group (P<0.001). Mortality did not show a statistically significant between-group difference (P=0.094). Surgical cases in the DHTAE group had a longer time from the accident scene to trauma center arrival (P=0.002). The time from the accident to the operation room or from the accident to angioembolization showed no statistically significant differences. Conclusions: DHTAE was associated with significantly longer transport times to the trauma center, as well as nonstatistically significant trends for delays in receiving surgery and procedures, as well as higher mortality. If severe trauma is suspected, air transport to a trauma center should be requested immediately after a simple screening test (e.g., mechanism of injury, Glasgow Coma Scale, or Focused Assessment with Sonography in Trauma), which may help reduce the time to definitive treatment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.160-164
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• 1991

The effect of various parameters, such as temperature, current density and operating valtage on the performance of phosphoric acid fuel cell stack was studied by using numerical analysis. The utilization ratio of reaction gas, inlet condition of reaction air and cooling air, inlet condition of cooling air flow latin were changed regularly, The results showed good agreements with the existing results and experimental ones.

• Reproductive and Developmental Biology
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• v.37 no.3
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• pp.97-102
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• 2013

The objective of this study was to develop of semen transport system for cryopreservation and fertility in bull sperm. The ejaculated semen were diluted with Triladyl containing 20% egg-yolk for transportation. Diluted semen was transported by three methods that there were wrapping tissue (Tissue), sinking under $30^{\circ}C$ water (Water) and sinking between warm water and air (Air) methods. Semen was transported within 2 hours in $0.3^{\circ}C$. For this study, the freezing of diluted semen were added with Triladyl containing 20% egg-yolk. And frozen-thawed sperm were estimated with SYBR14/PI double stain for viability, FITC-PNA/PI double stain for acrosome reaction analysis and Rhodamine123 double stain for mitochondrial intact assessment. In results, live sperm (SYBR+/PI-) in Air treatment group ($43.3{\pm}4.7%$) was significantly (p<0.05) higher than other treatment groups (Tissue: $16.3{\pm}2.7%$ and Water: $27.5{\pm}3.1%$), dying sperm (SYBR+/PI+) in Air treatment group ($55.6{\pm}4.7%$) was significantly lower than other treatment groups (Tissue: $77.6{\pm}3.2%$ and Water: $67.6{\pm}3.3%$) (p<0.05). Acrosome reaction in Air treatment group ($0.2{\pm}0.1%$) within live sperm (PI negative region) was significantly (p<0.05) lower than other treatment groups (Tissue: $0.7{\pm}0.2%$ and Water: $0.5{\pm}0.1%$), the acrosome reaction in Air treatment group ($28.6{\pm}2.8%$) within all sperm also was significantly lower than other treatment groups (Tissue: $44.2{\pm}1.8%$ and Water: $36.2{\pm}2.0%$) (p<0.05). And mitochondrial intact in Air treatment group within live ($97.1{\pm}0.4%$) and all ($61.9{\pm}3.3%$) sperm were significantly higher than other treatment groups (Tissue: $85.2{\pm}3.3%$, Water: $87.8{\pm}2.9%$ within live sperm and Tissue: $49.28{\pm}3.7%$, Water: $42.0{\pm}3.1%$ within all sperm) (p<0.05). Therefore, we suggest that transportation by sinking method between warm water and air was beneficial to improvement of fertility in frozen-thawed in bull semen.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.78
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• pp.1-29
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• 2018

This article demonstrates that both the Warsaw Convention Systemand the Montreal Convention are not designed for multimodal transport, let alone for "Door to Door" transport. The polemic directed against the "Door to Door" application of the Warsaw Convention systemand the Montreal Convention is predominantly driven by the text and the drafting philosophy of the said Contentions that since 1929 support unimodalism-with the rule that "the period of the carriage by air does not expend to any carriage by land, by sea or by inland waterway performed outside an airport" playing a profound role in restricting their multimodal aspirations. The drafters of the Montreal Convention were more adventurous than their predecessors with respect to the boundaries of the Montreal Convention. They amended Art. 18(3) by removing the phrase "whether in an aerodrome or on board an aircraft, or, in the case of landing outside an aerodrome, in any place whatsoever", however, they retained the first sentence of Art. 18(4). The deletion of the airport limitation fromArt. 18(3) creates its own paradox. The carrier can be held liable under the Montreal Convention for the loss or damage to cargo while it is in its charge in a warehouse outside an airport. Yet, damage or loss of the same cargo that occurs during its surface transportation to the aforementioned warehouse and vice versa is not covered by the Montreal Convention fromthe moment the cargo crosses the airport's perimeter. Surely, this result could not have been the intention of its drafters: it certainly does not make any commercial sense. I think that a better solution to the paradox is to apply the "functional interpretation" of the term"airport". This would retain the integrity of the text of the Montreal Convention, make sense of the change in the wording of Art. 18(3), and nevertheless retain the Convention's unimodal philosophy. English courts so far remain loyal to the judgment of the Court of Appeal in Quantum, which constitutes bad news for the supporters of the multimodal scope of the Montreal Convention. According the US cases, any losses occurring during Door to Door transportation under an air waybill which involves a dominant air segment are subject to the international air law conventions. Any domestic rules that might be applicable to the road segment are blatantly overlooked. Undoubtedly, the approach of the US makes commercial. But this policy decision by arguing that the intention of the drafters of the Warsaw Convention was to cover Door to Door transportation is mistaken. Any expansion to multimodal transport would require an amendment to the Montreal Convention, Arts 18 and 38, one that is not in the plans for the foreseeable future. Yet there is no doubt that air carriers and freight forwarders will continue to push hard for such expansion, especially in the USA, where courts are more accommodating.

• The Korean Journal of Air & Space Law and Policy
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• v.26 no.1
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• pp.93-125
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• 2011

The International Civil Aviation Convention (Chicago Convention) has been a backbone of international air transport system whereby air transport between States should be based on bilateral agreements, and in particular, international airfares, which are set up through IATA(International Air Transport Association) rate-fixing machinery could be approved by the governments concerned. International airfares are fares for transporting passenger and freight and their conditions between two or more countries. However, since U.S. pursued th deregulation policy in 1978 whereby routes, capacity and fares could be freely determined by airlines, many States have been following so called open-skies agreements. In many cases, aeronautical and competent authorities have been reviewing whether airlines' commercial activities including air fares could possibly conflict with free competition rules envisaged in relevant laws and regulations. As competition among airlines gets intense, airlines often resort to cooperation with other airlines in the forms such as equity exchange, M&A, code-sharing, fares consultation and resource pooling, mainly with a view to effectively use resources available and to avoid monopoly situation resulting from excessive and destructive competition among players. Whereas bearing in mind that application of competition laws is important to secure consumers' interests by preventing airlines's malpractices such as bargaining exorbitant fares, it is also important to comprehensively consider as many factors as possible, from that unilateral measure by governments may bring about retaliatory measures by the governments affected, to that airlines' cooperative practices may rather increase consumers' benefits by lowering air fares.

• Journal of Advanced Navigation Technology
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• v.21 no.3
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• pp.264-271
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• 2017

This paper presents air traffic control simulation model for generating 4D trajectory, and aircraft dynamic model based on 4D trajectory information. With aircraft parameters from BADA and Total Energy Model, the trajectory is defined through modified Bezier curve and the simulation supports two aircraft control methods based on controlled time of arrival (CTA) or airspeed. The simulation results shown that flight time and path were almost identical to the defined trajectory, and derived the differences of each control methods according to wind conditions. Based on the simulation model developed in this study, it is expected to be applied to various air traffic management researches. Future studies will focus on applying optimization techniques in order to minimize the difference between generated trajectories and actual flight routes. This work will increase utilization of developed simulation futhermore.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.1
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• pp.43-50
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• 2013

The stringent emission regulation and future shortage of fossil fuel motivate the research of alternative powertrain. In this study, a system of proton exchange membrane fuel cell has been modeled to analyze the performance of the fuel cell system for automotive application. The model is composed of the fuel cell stack, air compressor, humidifier, and intercooler, and hydrogen supply which are implemented by using the Matlab/Simulink(R). Fuel cell stack model is empirical model but the water transport model is included so that the system performance can be predicted over various humidity conditions. On the other hand, the model of air compressor is composed of motor, static air compressor, and some manifolds so that the motor dynamics and manifold dynamics can be investigated. Since the model is concentrated on the strategic operation of compressor to reduce the power consumption, other balance of components (BOP) are modeled to be static components. Since the air compressor model is empirical model which is based on curve fitting of experiments, the stack model is validated with the commercial software and the experiments. The dynamics of air compressor is investigated over unit change of system load. The results shows that the power consumption of air compressor is about 12% to 25% of stack gross power and dynamic response should be reduced to optimize the system operation.

• Journal of Korean Society of Disaster and Security
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• v.13 no.1
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• pp.51-58
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• 2020

This paper analyzes the effect of airflow of ceiling air conditioner on the operation of sprinkler head using a simulation program. The simulation space is 10 m × 7 m × 3 m, and the size of the fire is 0.8 m × 0.8 m × 0.6 m. The cold air flow from the air conditioner is at 25℃ and the wind speed is divided into three cases : 10 ㎧, 8.5 ㎧, and 7.5 ㎧. Simulation results show that all cases had operating delays compared to when the air conditioner was not running, and the sprinkler head did not operate until 10 minutes had elapsed at 10 ㎧ wind speed. These results confirmed that the sprinkler head was delayed in the air conditioning space and the worst result of early evolution failure was observed in strong winds such as 10 ㎧.