• The Korean Journal of Air & Space Law and Policy
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• v.11
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• pp.93-141
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• 1999

• Journal of Plant Biology
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• v.18 no.2
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• pp.45-52
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• 1975

Effects of air pollutants on vegetation were reviewed and discussed with special reference to sulfur dioxide. Main contents were on the sources, meteorological factors, injury symptoms, relative sensitivity, growth/yield, indicator/diagnosis, combined effects, injury mechanism and effects on plant metabolism, injury diminishing measures, and future research needs.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.636-640
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• 2014

This study was conducted to provide basic information about the drying methods (daylight, hot-air, and freeze drying) used for Platycodon grandiflorum radix. We investigated the mineral, free sugar, and saponin contents of dried P. grandiflorum. The potassium and calcium contents of hot-air-dried samples were the highest (22.6 and 9.2 mg%, respectively), when compared to those of daylight- or freeze-dried samples. Glucose and sucrose contents were the highest in freeze-dried samples (1,552 and 145.0 mg%, respectively), while fructose content was the highest in hot-air-dried samples (611.9 mg%). Platycodin D content was the highest in hot-air-dried samples (622.0 mg%); however platycodin D3, polygalacin D, and deapioplatycodin D contents were the highest in daylight-dried plant (113.5, 756.6, and 109.2 mg%, respectively). Glucose content was highly negatively correlated (p<0.01) with platycodin D, platycodin D3, and deapioplatycodin D (-0.924, -0.957, -0.861, p<0.01, respectively). These results suggest that the drying method affects the saponin content of P. grandiflorum and daylight and hot-air drying methods are more suitable and beneficial than freeze-drying.

• Food Science and Preservation
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• v.8 no.3
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• pp.239-245
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• 2001

The CA(Controlled Atmosphere) storage of cherry tomatoes were carried out under seven gas compositions including air. The weight loss of cherry tomatoes progressively increased with storage time. In the case of cherry tomatoes stored under CA conditions, increment of weight loss was reduced. However, cherry tomatoes (in air) tut about 15% weight at the end of storage. In CA stored cherry tomatoes lost about 10% weight at the same time. General trend was a decrease in titratable acidity with storage time. In air md 6.4% O$_2$, 4.2% CO$_2$, titratable acidity was lower than that in other storage conditions. During storage of cherry tomatoes, soluble solids increased till 8 days of storage, and then decreased. Stored cherry tomatoes in air and 6.4% O$_2$+4.2% CO$_2$ have lower values. Lycopene contents of cherry tomatoes with 6% O$_2$ storage condition increased and cherry tomatoes with 1% O$_2$+6% CO$_2$ and 3% O$_2$+3.1% CO$_2$maintained s initial contents. In air, flesh firmness decrease till 8 days, and then increase. At 1% O$_2$+6% CO$_2$ ethanol contents were ten times to that of other experimental conditions. Air and 6% O$_2$+7.8% CO$_2$ condition had lowest value for the ethanol content. In changes of organic acid and citric acid decreased slowly during storage, malic acid in air and below 3% O$_2$was disappeared at 8 days. Above 4% O$_2$concentration malic acid contents were maintained till 16 days. In over all acceptability, air and 6.4% O$_2$+7.8% CO$_2$ condition took a good score from the panel. Quality of stored cherry tomatoes was not edible condition in 1% O$_2$+6% CO$_2$. CA storage cherry tomatoes took a good score in firmness and juiciness where as control received good score in color and sweetness. This result was explained that in air ad 6.4% O$_2$+7.8% CO$_2$stored cherry tomato was ripened and full color development, but in CA was break stage because of suppressed ripening.

• International Journal of Contents
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• v.6 no.3
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• pp.89-96
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• 2010

The International air transportation industry provides a vital communication link which brings prosperity to many states in our modern age. This invaluable link has been threatened by terrorism. Airlines have been one of the most attractive targets in the eyes of terrorists for several reasons, including particularly the international and symbolic nature of aviation, and the potential of multigovernmental involvement which can inevitably generate wide publicity. Terrorist attacks against civil aviation have been committed since the earliest days of civil aviation history. The first attack against civil aircraft dates back to the early 1930s. Since then, aircraft hijacking and other forms of attack against air transport operations have become one of the most serious challenges to the safety of flying. In recent years, a new form of threats against civil aviation has appeared. Man-portable air defense systems (MANPADS) in the hands of criminals, terrorists, and other non-state actors pose a serious potential threat to passenger air travel, the commercial aviation industry, and military aircraft around the world. The purpose of this study is to provide some countermeasures against such attacks. In order to foster a better understanding of the problem, an introduction of MANPADS and a brief history of attacks using MANPADS are presented. It also examines the level of threats, trends of attacks using MANPADS and the possible countermeasures to be taken by the international community.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.2
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• pp.55-66
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• 2021

ICAO recommended that airspace monitoring and periodic safety assessments in each Contracting State ensure the stability of the airspace, since reducing the aircraft lateral and vertical separation intervals would rather increase the risk of collision. The target level of safety of the AKARA-FUKUE Corridor at the southern end of Jeju was 247×10^-9. In simple comparison, this means that the risk of an aircraft collision in this area (international safety standards, 5.0×10^-9) is about 50 times higher. The scope of this study is to organize the concept of terms, analyze the air traffic volume, the current status of navigational safety facility usage fees, and investigations of an aircraft collision risk in Jeju southern air corridor. Analyzing government policies and overseas evaluations, revising some of the existing contents, presenting some of the additional contents of new routes, and changing the instrument procedure for Korean-Chinese routes, change of arrive/departure route between Incheon Airport and Shanghai Airport, reduce the risk of aircraft collisions. We hope to restore airspace sovereignty, contribute to policies for the government to take the lead in solving this problem, and expect stability and operational efficiency in air traffic.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.229-236
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• 2010

As air pollution has emerged as one of the most pressing urban environmental concerns, many studies have investigated the influence of air pollutants(ex: $O^3$, $NO^2$, $SO^2$, Acid rain, etc.) on roadside trees and urban grove. In Korea, population density started to increase since the industrialization. Since dense population aggravates our living conditions, it's very important for us to preserve and keep a lively and refreshing nature in order to live with green nature in harmony under the current artificial environment-dominating world. In metropolitan cities, the production of pollutants increases in proportion to population growth. The vehicle exhaust gas and air pollutants from cooling and heating systems have been the major causes of acid rain. Furthermore, tire particles which are naturally produced by tire wearing on roads and other toxic substances in exhaust gas have caused a problem in human health directly and indirectly. In fact, a lot of studies have analyzed air pollution, roadside trees and plants in Korea. However, they are mostly limited to covering the influence of air pollution on the growth of plants. No paper has clearly explained why air pollution-resistant or-vulnerable species has shown different reactions yet. Even though a lot of urban roadside trees have died or stopped to grow from time to time, this kind of problem has not been properly examined. This paper is aimed to comparatively analyze physio-ecological characteristic such as photosynthesis, chlorophyll contents, soil volume water figure out their relationship with environmental factors against the expanding roadside trees in Cheong-ju, and provide basic data for management of roadside trees and elaboration of urban environment preservation policies.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.388-395
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• 2000

This study was performed to examine the effects of infrared (IR)/heated-air combination drying on some quality attributes of Korean white ginsengs. Ginseng roots were dried in a dryer where both the far infrared ray and heated-air are available as drying energy sources. Diametral shrinkage, external color, total saponin content, and ginsenosides and free sugar composition of the IR/heated-air combination dried ginsengs were measured and compared with those of commercial white ginseng products. The external color became lower in lightness and higher in saturation as the IR radiating plate temperature increased. IR/heated-air combination dried white ginsengs at IR plate temperature of 100$^{\circ}C$ was comparable to the commercial white ginseng products in color characteristics. Diametral shrinkage ratios ranged from 20 to 36% and appeared to be independent on the different drying methods. No definite evidence could be found whether the IR/heated-air combination drying and the conventional. hot-air drying practice resulted in white ginsengs having different ginsenoside contents and compositions. No conclusion could be made on whether the various drying treatments used in the study had effects on the free sugar contents and compositions of white ginsengs.

• Hwankyungkyoyuk
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• v.21 no.4
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• pp.40-66
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• 2008

The purpose of this study is to develop and applicate textbook relevant to school indoor air quality. To achieve the purpose, concrete study process are as follows. First, the survey research to teachers, supervisors, and students is conducted to grasp cognition of subjects in elementary school and management situation about school indoor air quality. Second, contents relevant to indoor air quality on textbooks in the 7th elementary curriculum and subsidiary textbooks is analysed through reference study. Third, environmental textbook relevant to school indoor air quality for 5th and 6th grade in elementary school is developed, applicated, and inspected its effect on the basis of implications from results of survey and reference study. The results of this study are as follows. First, the result of survey concerning school indoor air quality showed that three groups had negative attitude for its management even though they thought that it affected human's health and study by and large. Student group thought that each of students itself was a little influence to school indoor air pollution though all of three groups answered that' activities of students' was its main source. Efforts of students to improve school indoor air quality was not much, and its main reason was that they didn't know about school indoor air pollution well. Second, result of analysis into textbooks on the 7th elementary curriculum and subsidiary textbooks, contents concerning indoor air on the 7th elementary curriculum textbooks was little or nothing. And it trended to be included to subsidiary textbooks. However, education textbooks about indoor air for elementary students was insufficient still. Third, environmental textbook relevant to school indoor air quality for 5th and 6th grade in elementary school was developed. It was constructed for themes - importance, sources, effects, and management of school indoor air quality. After its application to the 6th grade students in elementary school, it was meaningful in the level of p<.05 that the result of knowledge and awareness in the pre-post test within experiment group. However, all of the results in comparison group didn't represent statistically meaningful difference. In conclusion, environmental textbook developed by necessity of education about school indoor air quality will play a role as useful tool for the 5th, 6th grade students in elementary school to understand relation of quality of health and life and school indoor air quality, to have attitude to make an effort to manage it by develop right awareness about it.

• Proceedings of the Korea Contents Association Conference
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• 2003.11a
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• pp.352-366
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• 2003

Exploiting a multiply warped products manifold scheme, we study the interior solutions of the (2.1) Banados-Teitelboim-Zanelli black holes and the exterior solutions of the (2+1) do Sitter black holes.