• Title/Summary/Keyword: 2-자유도 시스템

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The Applications of Antioxidant Impregnated Polymers to Food Packaging (식품포장의 항산화제 첨가 플라스틱의 용도)

  • Lee, Youn-Suk
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.8 no.2
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    • pp.49-59
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    • 2002
  • The main function of plastic materials in food packaging is to preserve a food for safe transportation and storage. The interactions between food and plastic materials in food packaging have become increasingly important for food quality and safety because monomer, low molecular weight components, or additives of plastic packaging materials can migrate into a food. The use of antioxidants in plastic materials can help protect the degradation of film itself and retard the oxidation of a packaged food containing lipid, through the migration of antioxidant from the packaging to a product via an evaporation / sorption mechanism. Nowadays, antioxidant (BHT) impregnated plastic materials are used for commercial food packaging application with the intention of achieving an extended shelf life of food in USA. Alpha tocopherol, as one of the most important free radical scavengers, has been well known in biological systems. Moreover, the potential use of alpha tocopherol as an additive for polymers used in the packaging industry may offer the most positive perception from both consumers and manufacturers. Alpha tocopherol has been used as an antioxidant for polyolefin resins fabricated to both bottles and film and has applications in the food packaging industry as a replacement for BHT. Today, alpha tocopherol offers an attractive choice for use as an antioxidant in polymers. This paper provides an overview of antioxidant effectiveness and applications for its use by the food packaging industry based on the evaporation-sorption mechanism of a packaging model product, where quality is associated with lipid oxidation. Important analytical techniques for predicting antioxidant interaction between the package system and product are discussed.

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A Case Study on the Industry-Academy-Government Cooperation to Intensify Export Competitiveness of Local SMEs - Focused on Gyeongbuk PRIDE Products - (지역중소기업 수출경쟁력 강화를 위한 산.학.관 협력모델에 관한 사례 연구 - 경북PRIDE상품 육성사업을 중심으로 -)

  • Yeo, Taek-Dong;Lee, Hee-Young
    • International Commerce and Information Review
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    • v.14 no.2
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    • pp.411-443
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    • 2012
  • The Changes in management environment in SMEs such as rapid development of information communication technology, worldwide expansion of FTAs, enlargement of global outsourcing, etc have changed various aspects in industry-academy or industry-academy-government cooperation. It has been away from the cooperation focused on research and development and industrial training, and advanced to the cooperation focused on the business fields and practices where the executive ability and professionalism are required to commercialize major products of local SMEs. Compared with the existing model, the new model of industry-academy-government cooperation can provide effective and customized supports to local SMEs and expect better performance than ever before through the choice and focus. However, the existing support programs of government and related organizations are just top-down pattern to SMEs. In addition to the development of industrial technology, education and training for labor force and knowledge interchange between industry and university, the new cooperation model would also provide practical tasks such as enhancement of business competences and abilities to cultivate foreign markets. This study deals with Gyeongbuk PRIDE Products support project that is the new model of industry-academy-government cooperation and evaluates the effectiveness of this support project by empirically analyzing the survey results from the target SMEs.

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Isotherm, Kinetic, Thermodynamic and Competitive for Adsorption of Brilliant Green and Quinoline Yellow Dyes by Activated Carbon (활성탄에 의한 Brilliant Green과 Quinoline Yellow 염료의 흡착에 대한 등온선, 동력학, 열역학 및 경쟁흡착)

  • Lee, Jong Jib
    • Korean Chemical Engineering Research
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    • v.59 no.4
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    • pp.565-573
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    • 2021
  • Isotherms, kinetics and thermodynamic properties for adsorption of Brilliant Green(BG), Quinoline Yellow(QY) dyes by activated carbon were carried out using variables such as dose of adsorbent, pH, initial concentration, contact time, temperature and competitive. BG showed the highest adsorption rate of 92.4% at pH 11, and QY was adsorbed at 90.9% at pH 3. BG was in good agreement with the Freundlich isothermal model, and QY was well matched with Langmuir model. The separation coefficients of isotherm model indicated that these dyes could be effectively treated by activated carbon. Estimated adsorption energy by Temkin isotherm model indicated that the adsorption of BG and QY by activated carbon is a physical adsorption. The kinetic experimental results showed that the pseudo second order model had a better fit than the pseudo first order model with a smaller in the equilibrium adsorption amount. It was confirmed that surface diffusion was a rate controlling step by the intraparticle diffusion model. The activation energy and enthalpy change of the adsorption process indicated that the adsorption process was a relatively easy endothermic reaction. The entropy change indicated that the disorder of the adsorption system increased as the adsorption of BG and QY dyes to activated carbon proceeded. Gibbs free energy was found that the adsorption reaction became more spontaneous with increasing temperature. As a result of competitive adsorption of the mixed solution, it was found that QY was disturbed by BG and the adsorption reduced.

Numerical Study on the Effect of the Arrangement Type of Rotor Sail on Lift Formation (로터세일의 배열 형태가 양력 형성에 미치는 영향에 관한 수치해석적 연구)

  • Jung-Eun Kim;Dae-Hwan Cho;Chang-Yong Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.2
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    • pp.197-206
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    • 2023
  • Recently, the international community, including the International Maritime Organization (IMO), has strengthened regulations on air pollution emissions of ships, and eco-friendly ships are actively being developed to reduce exhaust gas emissions. Among them, rotor sail (RS), a wind-assisted ship propulsion system, is attracting attention again. RS is a cylindrical device installed on the ship deck, that generates hydrodynamic lift using a magnus effect. This is a next generation eco-friendly auxiliary propulsion technology, and Enercon company, which developed RS-applied ships, announced that fuel savings of more than 30% are possible. In this study, optimal installation conditions such as RS spacing and arrangement type were selected when multiple RSs were installed on ships. AR=5.1, SR=1.0, and De/D was fixed at 2.0 according to the RS arrangement, and the wind direction was considered only for the unidirectional +y-axis. Regarding arrangement conditions, five conditions were set at 3D intervals in the +x-axis direction from 3D to 15D and five conditions in the +y-axis direction from 5D to 25D. CL, CD and aerodynamic efficiency (CL/CD) were compared according to the square(□) and diamond(◇) shape arrangements. Consequently, the effect of RS on the longitudinal distance was not significantly different. However, in the case of RS flow characteristics according to the transverse distance, the interaction effect of RS was the greatest when the two RSs almost matched the wind direction. In the case of the RS flow characteristics according to the arrangement, notably, when the wind blew in the forward (0°) direction, the diamond (◇) arrangement was least affected by the backward flow between RSs.

Advanced Treatment of Sewage and Wastewater Using an Integrated Membrane Separation by Porous Electrode-typed Electrolysis (분리막/다공 전극형 전기분해 조합공정을 이용한 하.폐수의 고도처리)

  • Choi, Yong-Jin;Lee, Kwang-Hyun
    • Membrane Journal
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    • v.22 no.2
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    • pp.95-103
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    • 2012
  • To treat nitrate and non-biodegradable organics effectively in sewage, industrial wastewater and livestock wastewater, the activated sludge process integrated by a membrane separation and a porous electrode- electrolysis was proposed and its efficiency was investigated. The proposed system was consisted of 3 processes; activated sludge, membrane filtration and electrolysis. In the study, the membrane filtration played a role in reducing the load of the electrolysis to operate the proposed process stably. The electrolysis consisted of a porous electrode to increase the efficiency due to the extension of the specific surface area. Additionally, redox reaction in the electrolysis was induced by decomposing influent water as current was applied. As a result, hydrogen free radicals and oxygen radicals as intermediates were produced and they acted as oxidants to play a role in decomposing non-degradable organics. It was environmentally-friendly process because intermediates produced by porous electrode were used to treat waste matters without supplying external reagent. Experimental data showed that the proposed process was more excellent than activated sludge process. SS removal efficiencies of the proposed process, membrane filtration and activated sludge process were about 100%, about 100% and about 90%, respectively. COD removal efficiencies of the proposed system, membrane filtration and activated sludge process were about 92%, about 84% and about 78%, respectively. T-N removal efficiencies of the proposed system, membrane filtration and activated sludge process were about 88%, about 67%, and about 58%, respectively. The SS data showed that SS was efficiently removed in the single of the membrane filtration. The COD/T-N data showed that COD/T-N of membrane hybrid process was treated by removing a little soluble organics and SS, and that COD/T-N of electrolysis hybrid process was treated by oxidize organics with high removal rate.

Effect of Pyroligneous Liquor on Oxygen Radicals and Their Scavenger Enzymes in Liver of CD Rats (흰쥐 간조직의 활성산소 및 제거효소에 미치는 목초액의 영향)

  • Choi, Jin-Ho;Cho, Weon-Ki
    • Journal of Nutrition and Health
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    • v.40 no.2
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    • pp.111-117
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    • 2007
  • This study was designed to investigate the effects of pyroligneous liquor on oxygen radicals and their scavenger enzymes in the liver of Cri/Bgi CD rats (7 rats per group). Male rats were fed a basic diet prepared in our Lab., PL-0 (Control), PL-1, PL-25, PL-50 and PL-75 groups were Prepared to be 0%, 1%, 25%, 50% and 75%with distilled water using pyroligneous liquor (35% of Choa Co. Ltd.), and were administrated orally for 8 weeks. Superoxide radical contents in liver mitochondria and microsomes were significantly decreased to 12-14%, 11-15%, respectively, in these PL-25 and PL-50groups compared with the control group. Hydroxyl radical content in mitochondria and microsomes were markedly decreased to 12-20% and 17%, respectively, in these PL-25 and PL-50% groups compared with the control group. Hydrogen peroxide content in mitochondria and microsomes were significantly decreased about 15-12% and 22-20% in liver of PL-25 and PL-50 groups compared with the control group. Mn-SOD and Cu/Zn-SOD activities in liver of PL-25 and PL-50 groups were remarkably increased to 15-25%, 11-16%, respectively, compared with the control group. GPx activities in mitochondria and microsomes were significantly increased in the liver of PL-25 and PL-50 groups compared with the control group. CAT activities in mitochondria and cytosol were significantly increased to 12-14%, 15-27%, respectively, in the liver of PL-25 and PL-50 groups compared with the control group. These results suggest that long term administration orally of 25 and 50% pyroligneous liquor may effectively inhibit the formation of oxygen free radicals, and also scavenger enzyme activities significantly increase through the administration orally.

Evaluation of Antioxidant, Cytoprotective and Antimicrobial Properties of Polygoni multiflori Radix Extract, Fractions and Its Major Constituent (하수오 추출물, 분획물 및 주성분의 항산화, 세포 보호 및 항균 활성에 관한 평가)

  • Shin, Hyuk Soo;Kim, Minwoo;Song, Jerry;Lee, Junseok;Ha, Yoonjeong;Jeon, Young Hee;Kim, Ji Woong;Lee, Yun Ju;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.44 no.4
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    • pp.407-417
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    • 2018
  • In this study, the antioxidant, cytoprotective and antimicrobial activities of 50% ethanol extract of Polygoni multiflori Radix (PMR) and its ethyl acetate fraction were evaluated to confirm the applicability as a functional ingredient. The activities of the major constituent of PMR were verified and 2, 3, 5, 4′-tetrahydroxystilbene 2-O-${\beta}$-D-glucoside (THSG) was confirmed to be the main component of extract and fraction using HPLC-DAD, LC-EIS-MS analysis. The phenolic and THSG contents of the ethyl acetate fraction were 11.1- and 3.0-folds higher than those of the ethanol extract, respectively. As a result of the DPPH assay and that of luminol dependent chemiluminescence assay in $Fe^{3+}$-EDTA/H2O2 system. the ethylacetate fraction was superior to the ethanol extract in free radical and ROS scavenging activities. Especially, the ethyl acetate fraction and THSG exhibited the similar scavenging activity like L-ascorbic acid in ROS scavenging activity. The ethyl acetate fraction perceived the most potent cytoprotective effect against oxidative damage of erythrocytes induced by photosensitization reaction, followed by the ethanol fraction, THSG and that of (+)-${\alpha}$-tocopherol, which was used as a positive control. Antimicrobial activities were evaluated by disc diffusion and broth microdilution assay against S. aureus, E. coli, P. aeruginosa and C. albicans. In particular, the antibacterial activity of the extract and fraction against S. aureus was superior to that of methyl paraben. Taken together, our results suggest that PMR could be used as a natural ingredient for antioxidant, cytoprotective and antimicrobial activities.

The Effect on Air Transport Sector by Korea-China FTA and Aviation Policy Direction of Korea (한·중 FTA가 항공운송 부문에 미치는 영향과 우리나라 항공정책의 방향)

  • Lee, Kang-Bin
    • The Korean Journal of Air & Space Law and Policy
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    • v.32 no.1
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    • pp.83-138
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    • 2017
  • Korea-China FTA entered into force on the 20th of December 2015, and one year elapsed after its effectuation as the FTA with China, our country's largest trading partner. Therefore, this study looks at the trends of air transport trade between Korea and China, and examines the contents of concessions to the air transport services sector in Korea-China FTA, and analyzes the impact on the air transport sector by Korea-China FTA, and proposes our country's aviation policy direction in order to respond to such impact. In 2016 the trends of air transport trade between Korea and China are as follows : The export amount of air transport trade to China was 40.03 billion dollars, down by 9.3% from the last year, and occupied 32.2% of the total export amount to China. The import amount of air transport trade from China was 24.26 billion dollars, down by 9.1% from the last year, and occupied 27.7% of the total import amount from China. The contents of concessions to the air transport services sector in Korea-China FTA are as follows : China made concessions to the aircraft repair and maintenance services and the computer reservation system services with limitations on market access and national treatment in the air transport services sector of the China Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. Korea made concessions to the computer reservation system services, selling and marketing of air transport services, and aircraft repair and maintenance without limitations on market access and national treatment in the air transport services sector of the Korea Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. The impact on the air transport sector by Korea-China FTA are as follows : As for the impact on the air passenger market, in 2016 the arrival passengers of the international flight from China were 9.96 million, up by 20.6% from the last year, and the departure passengers to China were 9.90 million, up by 34.8% from the last year. As for the impact on the air cargo market, in 2016 the exported goods volumes of air cargo to China were 105,220.2 tons, up by 6.6% from the last year, and imported goods volumes from China were 133,750.9 tons, up by 12.3% from the last year. Among the major items of exported air cargo to China, the exported goods volumes of benefited items in the Tariff Schedule of China of Korea-China FTA were increased, and among the major items of imported air cargo from China, the imported goods volumes of benefited items in the Tariff Schedule of Korea of Korea-China FTA were increased. As for the impact on the logistics market, in 2016 the handling performance of exported air cargo to China by domestic forwarders were 119,618 tons, down by 2.1% from the last year, and the handling performance of imported air cargo from China were 79,430 tons, down by 4.4% from the last year. In 2016 the e-commerce export amount to China were 109.16 million dollars, up by 27.7% from the last year, and the e-commerce import amount from China were 89.43 million dollars, up by 72% from the last year. The author proposes the aviation policy direction of Korea according to Korea-China FTA as follows : First, the open skies between Korea and China shall be pushed ahead. In June 2006 Korea and China concluded the open skies agreement within the scope of the third freedom and fourth freedom of the air for passenger and cargo in Sandong Province and Hainan Province of China, and agreed the full open skies of flights between the two countries from the summer season in 2010. However, China protested against the interpretation of the draft of the memorandum of understanding to the air services agreement, therefore the further open skies did not take place. Through the separate aviation talks with China from Korea-China FTA, the gradual and selective open skies of air passenger market and air cargo market shall be pushed ahead. Second, the competitiveness of air transport industry and airport shall be secured. As for the strengthening methods of the competitiveness of Korea's air transport industry, the support system for the strengthening of national air carriers' competitiveness shall be prepared, and the new basis for competition of national air carriers shall be made, and the strategic network based on national interest shall be built. As for the strengthening methods of the competitiveness of Korea's airports, particularly Incheon Airport, the competitiveness of the network for aviation demand creation shall be strengthened, and the airport facilities and safety infrastructure shall be expanded, and the new added value through the airport shall be created, and the world's No.1 level of services shall be maintained. Third, the competitiveness of aviation logistics enterprises shall be strengthened. As for the strengthening methods of the competitiveness of Korea's aviation logistics enterprises, as the upbringing strategy of higher added value in response to the industry trends changes, the new logistics market shall be developed, and the logistics infrastructure shall be expanded, and the logistics professionals shall be trained. Additionally, as the expanding strategy of global logistics market, the support system for overseas investment of logistics enterprises shall be built, and according to expanding the global transport network, the international cooperation shall be strengthened, and the network infrastructure shall be secured. As for the strengthening methods of aviation logistics competitiveness of Incheon Airport, the enterprises' demand of moving in the logistics complex shall be responded, and the comparative advantage in the field of new growth cargo shall be preoccupied, and the logistics hub's capability shall be strengthened, and the competitiveness of cargo processing speed in the airport shall be advanced. Forth, in the subsequent negotiation of Korea-China FTA, the further opening of air transport services sector shall be secured. In the subsequent negotiation being initiated within two years after entry into force of Korea-China FTA, it is necessary to ask for the further opening of the concessions of computer reservation system services, and aircraft repair and maintenance services in which the concessions level of air transport services sector by China is insufficient compared to the concessions level in the existing FTA concluded by China. In conclusion, in order to respond to the impact on Korea's air passenger market, air cargo market and aviation logistics market by Korea-China FTA, the following policy tasks shall be pushed ahead : Taking into consideration of national air carriers' competitiveness and nation's benefits, the gradual and selective open skies shall be pushed ahead, and the support system to strengthen the competitiveness of air transport industry and airport shall be built, and entry into aviation logistics market by logistics enterprises shall be expanded, and the preparations to ask for the further opening of air transport services sector, low in the concessions level by China shall be made.

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A Rapid Analysis of 226Ra in Raw Materials and By-Products Using Gamma-ray Spectrometry (감마분광분석을 이용한 원료물질 및 공정부산물 중 226Ra 신속분석방법)

  • Lim, Chung-Sup;Chung, Kun-Ho;Kim, Chang-Jong;Ji, Young-Yong
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.1
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    • pp.35-44
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    • 2017
  • A gamma-ray peak of $^{226}Ra$ (186.2 keV) overlaps with one of $^{235}U$ (185.7 keV) in a gamma-ray spectrometry system. Though reference peaks of $^{235}U$ can be used to correct the peak interference of $^{235}U$ in the analysis of $^{226}Ra$, this requires a complicated calculation process and a high limit of quantitation. On the other hand, evaluating $^{226}Ra$ using the correction constant in the overlapped peak can make a rapid measurement of $^{226}Ra$ without the complicated calculation process as well as overcome the disadvantage in the indirect measurement of $^{214}Bi$, which means the confinement of $^{222}Rn$ gas in a sample container and a time period to recover the secular equilibrium. About 93 samples with 6 species for raw-materials and by-products were prepared to evaluate the activity of $^{226}Ra$ using the correction constant. The results were compared with the activity of $^{214}Bi$, which means the indirect measurement of $^{226}Ra$, to validate the method of the direct measurement of $^{226}Ra$ using the correction constant. The difference between the direct and indirect measurement of $^{226}Ra$ was generally below about ${\pm}20%$. However, in the case of the phospho gypsum, a large error of about 50% was found in the comparison results, which indicates the disequilibrium between $^{238}U$ and $^{226}Ra$ in the materials. Application results of the contribution ratio of $^{226}Ra$ were below about ${\pm}10%$. The direct measurement of $^{226}Ra$ using the correction constant can be an effective method for its rapid measurement of raw materials and by-products because the activity of $^{226}Ra$ can be produced with a simple calculation without the consideration of the integrity of a sample container and the time period to recover the secular equilibrium.

Current Situation and Cooperation on the Metropolitan Airport between Korea and Japan (한국 및 일본의 수도권 공항의 현황과 협력)

  • Kim, Doo-Hwan
    • The Korean Journal of Air & Space Law and Policy
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    • no.spc
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    • pp.137-163
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    • 2007
  • The air market in Asia has already entered upon the age of limitless competition. It means a very important moment in Asia air market. Each Asian country thus has put a lot of effort into a development plan and support to their hub airport. In order to achieve such a plan, first of all we should build closer cooperation system between the two countries Japan and Korea. The Korea and Japan are very fast growing in the northeast countries within the global air transport market. Air passenger and cargo traffic volumes between Korea and Japan have increased dramatically, since the 1990s. In response to such a trend, both countries have opened new airports and expanded existing facilities in the hopes of laying claims to the main international hub airport in Asia. Apart from the trend, air transportation between Korea and Japan's metropolitan areas is the only transportation in substance, even if they are located very closely in geographical position. The air transportation between the two countries shows that it is necessary to get fast and more convenient because of the economic and cultural interchange and exchange concentrated on the metropolitan areas, and that will promote the economic growth of Korea and Japan. However, within the air transportation industry field, there have no sufficient seats/slots to supply the air demand from the capital cities of each country, as well as no counterplan for some problems regarding capacityand sustain ability of metropolitan airports. Thus, it is necessary for us to consider in all aspects and solve them to improve air transportation between Korea and Japan. This paper is to try to demonstrate this matter and from all angles, that is, in legal and political aspects, facilities and given environmental conditions and cooperation between Korea and Japan. I think that it is indeed a great necessary and convenient for many Korean and Japanese tourists to conclude a new 'Open Sky Agreement' between Japan and Korea in order to the prepare the increase of the shuttle flight between Haneda-Gimpo and opening of air route newly for shuttle flight between Haneda and Cheongju as well as opening of air route for shuttle flight between Haneda-Shanghai Hongqiao International Airport and Beijing International Airport for the 2008 Beijing Olympic Games. Furthermore it is a great desirable thing for us to conclude a new 'Open Sky Agreement' in cooperation reciprocally among the Japan, China and Korea for opening the new air route by the shuttle flight.

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