• Asian Journal of Atmospheric Environment
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• v.2 no.1
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• pp.54-59
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• 2008

The most pivotal approach to improve subway indoor air quality (IAQ) is to examine the emission sources and particulate behavior. Therefore, the main objective of this study is to investigate the particulate behavior in the subway. In order to examine IAQ in the subway, a sampling and measurement campaign was carried out for 35 sites during the summer and winter seasons from May, 2005 to February, 2006. In case of 24 hour measurement, the mean concentrations ($PM_{10}$-24 hr) of platform and waiting room were $156.18{\pm}53.79{\mu}g/m^3$ and $111.00{\pm}53.31{\mu}g/ m^3$. Besides, as a result of 20 hour measurement, the mean concentrations ($PM_{10}$-20 hr) of platform and waiting room were $146.09{\pm}53.71{\mu}g/m^3$ and $99.08{\pm}42.77{\mu}g/m^3$, respectively. In general, $PM_{10}$-24 hr was higher than $PM_{10}$-20 hr, and both PM concentrations showed a high correlation coefficient (r=0.803). It was found that the $PM_{2.5}$ concentration ($l09.56{\pm}28.24{\mu}g/m^3$) in winter was higher than that ($83.66{\pm}57.82{\mu}g/m^3$) in summer.

• Journal of National Security and Military Science
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• s.2
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• pp.121-163
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• 2004

Science technique development expanded into, not only land, sea, and air operations but also those of airspace, and cyber battle spaces. It is generally accepted at this time that space centric operations currently cannot be effectively divided from air operations. However, science and technology advancements make it possible to integrate Army, Navy, Airforce, and Marine forces into effective operations as never before. The Republic of Korea Armed Forces needs to establish a more effective joint concept. The US military, considered by many experts as the most effective in the world, understands the necessity of joint operations and accordingly has highly developed its own concept of joint operations. The US joint operational concepts demonstrated their effectiveness during the Iraqi War by dominating the battlefield through effective use of all combat and non-combat power. Following the US Iraqi War experience, the US Department of Defense continued to enhance Joint Capability through the acceleration of US Military Transformation involving all components. The future national security of the Republic of Korea, faced with the peculiarity of communist threat in the form of North Korea, and the conflicting interest of four strong powers; the United States, China, Japan, and Russia, depends on small but strong armed forces employing all available combat power through effective National and Military Strategy, and considering domestic and international constraints. In order to succeed in future wars, military operations following joint operational concepts must effectively employ all available combat power in a timely manner. The Republic of Korea Armed Forces must establish a joint forces concept in order to integrate all available combat power during employment. Therefore we must establish military operations that develop the military structure and organization, doctrine, weapon systems, training and education of our armed forces based on the key concept of joint operations.

• Tuberculosis and Respiratory Diseases
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• v.83 no.3
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• pp.175-184
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• 2020

Quantitative sputum cytometry facilitates in assessing the nature of bronchitis associated with exacerbations of chronic obstructive pulmonary disease (COPD). This is not assessed in most clinical trials that evaluate the effectiveness of strategies to prevent or to treat exacerbations. While up to a quarter of exacerbations may be associated with raised eosinophil numbers, the vast majority of exacerbations are associated with neutrophilic bronchitis that may indicate airway infections. While eosinophilia may be a predictor of response to corticosteroids (oral and inhaled), the limited efficacy of anti-interleukin 5 therapies would suggest that eosinophils may not directly contribute to those exacerbations. However, they may contribute to airspace enlargement in patients with COPD through various mechanisms involving the interleukin 13 and matrix metalloprotease pathways. The absence of eosinophils may facilitate in limiting the unnecessary use of corticosteroids. The presence of neutrophiia could prompt an investigation for the specific pathogens in the airway. Additionally, sputum measurements may also provide insight into the mechanisms of susceptibility to airway infections. Iron within sputum macrophages, identified by hemosiderin staining (and by more direct quantification) may impair macrophage functions while the low levels of immunoglobulins in sputum may also contribute to airway infections. The assessment of sputum at the time of exacerbations thus would facilitate in customizing treatment and treat current exacerbations and reduce future risk of exacerbations.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.689-703
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• 2019

The term quality or freshness of eggs in industrial production still poses concerns regarding whether washing is necessary. Therefore, the aims of this study were to examine the effects of different storage times and temperatures and to perform a comparison between washed and unwashed eggs. A total of 1000 washed and 1000 unwashed egg samples were stored at three different temperatures (5, 10, and $25^{\circ}C$) for 0 - 8 weeks and were used for the data collection. On the designated day, the eggs were processed to evaluate their internal and external quality traits, such as the Haugh unit, airspace volume, eggshell strength, pH, and microbiological profile. Significant differences (p < 0.05) were observed between the washed and unwashed eggs for each quality trait. The results indicate that storage between 5 and $10^{\circ}C$ better preserved the quality of eggs compared with the storage at $25^{\circ}C$ throughout the days of the storage. Overall, this study suggests that the storage time and temperature have a vital role in maintaining the quality of eggs which were significantly affected during storage. In addition, all the quality parameters differed between the washed and unwashed samples which is further responsible for deteriorating the quality of the eggs.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.5
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• pp.425-435
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• 2021

It is imperative to examine the regulatory trends of leading overseas aviation authorities to accelerate the effort to integrate emerging new air vehicle concepts such as UAS and eVTOL into the existing national airspace system. Whilst EASA seems to react swiftly in relation to regulatory framework by proposing new sets of customised special conditions to cope with a growing demand to introduce new aircraft concepts, understanding of such movement lags behind mainly due to the complexity of EASA's regulation structure, not to mention EU's legal system. Witnessing this situation, this paper reviewed the legal system of the EU which forms the basis of EASA's regulation system together with its own recently published UAS regulations so as to contribute towards the improvement of the aviation regulatory framework.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.3
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• pp.28-37
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• 2022

Obstacle Limitation Surface (OLS) is conceptual surface establishing the airspace around aerodromes to be maintained from obstacles to ensure safe aircraft operations. Despite advances in the technologies for aircraft, navigation systems and the development of new flight procedures, the criteria defining OLS have not been amended since its initial establishment, resulting in the overestimation of areas for height restriction. As there were requests to examine OLS at the 12th Air Navigation Conference and the 38th ICAO Assembly, the research on the OLS revision began in earnest and ICAO has proposed Obstacle Free Surface (OFS) and Obstacle Evaluation Surface (OES) as an alternative of the existing OLS. OFS is surfaces where obstacles shall not be permitted, and OES is ones where obstacles be evaluated with an aeronautical study and could be permitted under some conditions. The purpose of this study is to preemptively assess the efficiency and safety of OFS and OES by applying them to the second runway (15L/33R) of Incheon International Airport. The results show that OFS and OES are capable of serving the instrument flight procedure safely with a smaller obstacle clearance area compared to the existing OLS.

• Journal of Advanced Navigation Technology
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• v.26 no.5
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• pp.272-280
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• 2022

An aircraft carrier is a combat ship that acts as an aircraft base at sea and performs combat through aircraft mounted as a military ship operating the aircraft. The Navy proposed a 40,000-ton light aircraft carrier operation plan that could be equipped with vertical takeoff and landing fighter jets and helicopters around 2033, and based on this, this study examined the operation of aircraft control equipment among the aviation support systems required for operating light aircraft carriers in Korea. PriFly, TWR's ILARTS, ILM for airspace control, ASR, PAR, LAAS or RNAV, PALS (JPALS) for access control are required as essential equipment, and communication network and SCATT-16 are required along with URN-25 TACAN, ICLS (El/Az), ACLS OLS, MOVAS, IFLOLS, etc. This study consists of two parts, and part 2 will describe a specific control method on an aircraft carrier.

• Journal of Advanced Navigation Technology
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• v.27 no.1
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• pp.119-125
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• 2023

It is necessary to reduce aviation GHG(CO2) emission to ensure aviation sustainable development. Operational improvements may not contribute significantly to carbon reduction but it can sustatially reduce emission in a short term. ICAO has developed GANP and ASBU to optimize operations and countries are making efforts to expand infrastructure and develop technology. The legal barriers to operational improvement are based on the notion of state sovereignty under the Chicago Convention which allows countries to control inefficiencies based on borders or limit or prohibit the passage of aircraft. Chicago Convention does not grant unlimited freedom of air sovereignty and if the concept of state sovereignty is interpreted according to the times it is possible to achieve smooth operational improvement.

• Journal of Advanced Navigation Technology
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• v.27 no.4
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• pp.330-336
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• 2023

Rapid urbanization is rapidly progressing around the world, and urban problems such as traffic congestion, environmental pollution, and noise pollution are emerging, due to this urban concentration phenomenon, logistics and transportation costs are increasing. Urban Air Mobility(UAM) is a three-dimensional futuristic urban transportation that is expected to become an important transportation axis of smart cities as a service(MaaS) linked to roads, railways, and personal transportation. However, as of July 2023, research on airspace systems, Bertieport design, navigation, and communication for UAM operation is actively being conducted, but little research has been conducted on the concept of pilot education and training and education and training programs. Therefore, this paper aims to present a suitable plan for the domestic pilot training system through SWOT analysis of vertical takeoff and landing(VTOL) pilot education and training programs in the United States and Europe.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.1
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• pp.79-91
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• 2023

In response to the recent surge in aviation demand, major airports and aviation authorities continue to make efforts to formulate arrival and approach procedures that take into account efficient aircraft separation, noise and environmental issues of carbon (CO2) emissions. In order to ensure efficient traffic control and environmental issues, as a result, a new concept Trombone, Point Merge, etc. have been introduced and widely used in the domestic airspace. However, these new concept procedures which do not properly reflect the characteristics of the aircraft operation performance and the FMS vertical descent guidance hinder flight efficiency as well as bring in turn negative factors such as level-off flight and the use of drag device at the busiest phase of the flight descent operation, like the Continuous Descent Operation (CDO). Accordingly, throughout modification the current Standard Terminal Arrival Route (STAR) and Instrument Approach Procedure(IAP) that reflect the aircraft descent performance and the FMS guidance, the flight operation safety and efficiency is expected to be improved eventually. We herewith analyze and propose the way of improving flight efficiency in the arrival operation procedure by supplementary modification which consequently contribute to the aviation industry international competitiveness.