• Journal of Digital Convergence
• /
• v.18 no.5
• /
• pp.179-186
• /
• 2020

The purposes of this paper were: 1) to identify the structural changes of the northeast Asia airport network caused by the pandemic of COVID-19 using social network analysis (SNA) and 2) to suggest proposals for improving airport competitiveness. In this respect, the entire international air routes in northeast Asia airport collected data of 4-10 March 2019 and 9-15 March 2020 through schedules analyzer database of OAG. We found that both the density and centrality have decreased since the spread of COVID-19. The government and airport authorities need active support such as a reduction of various fees and a moratorium on transportation rights to overcome the crisis in the air transport industry. When the COVID-19 situation calms down in the future, we hope that further research will be conducted to identify the structural changes in the SNA aspects through the vast data establishment in countries such as the EU and America.

• Nuclear Engineering and Technology
• /
• v.38 no.2
• /
• pp.163-174
• /
• 2006

The $Ph{\acute{e}}bus$ FP project is an international reactor safety project. Its main objective is to study the release, transport and retention of fission products in a severe accident of a light water reactor (LWR). The FPT4 test was performed with a fuel debris bed geometry, to look at late phase core degradation and the releases of low volatile fission products and actinides. Post Test Analyses results indicate that releases of noble gases (Xe, Kr) and high-volatile fission products (Cs, I) were nearly complete and comparable to those obtained during $Ph{\acute{e}}bus$ tests performed with a fuel bundle geometry (FPT1, FPT2). Volatile fission products such as Mo, Te, Rb, Sb were released significantly as in previous tests. Ba integral release was greater than that observed during FPT1. Release of Ru was comparable to that observed during FPT1 and FPT2. As in other $Ph{\acute{e}}bus$ tests, the Ru distribution suggests Ru volatilization followed by fast redeposition in the fuelled section. The similar release fraction for all lanthanides and fuel elements suggests the released fuel particles deposited onto the plenum surfaces. A blockage by molten material induced a steam by-pass which may explain some of the low releases. The revaporisation testing under different atmospheres (pure steam, $H_2/N_2$ and steam /$H_2$) and up to $1000^{\circ}C$ was performed on samples from the first upper plenum. These showed high releases of Cs for all the atmospheres tested. However, different kinetics of revaporisation were observed depending on the gas composition and temperature. Besides Cs, significant revaporisations of other elements were observed: e.g. Ag under reducing conditions, Cd and Sn in steam-containing atmospheres. Revaporisation of small amounts of fuel was also observed in pure steam atmosphere.

• Journal of the Korean Institute of Navigation
• /
• v.21 no.3
• /
• pp.1-18
• /
• 1997

From the beginning of 1990s , also in the shipping industry, especially liner shipping industry competition has been more intensive and difference of the service quality among shipping companies has been learned . On the other hand, a shipping company has some limitations to do its international mission for itself just by broadening service area. For this reason, the necessity for the global strategi alliance among the shipping companies, which is orginally aimed at sharing of facilities and organixation, has been developed. Through strategic alliance, liner shipping companies do not need to input the additional capitals to increase the material assets such as vessel capacity and spread the risk by the enlargement of the market. Also, they can secure the competitive edge through efficient utilizaton of assets. The purpose of strategic alliance of Hanjin Shipping Ltd., can be summarized as follows ; broadening of service area, cost reduction through vessel sharing, realization of rationalized shipping service by terminal and equipment or facilities sharing. Liner strategic alliances are agreement among liner companies to pol their equipment , andterminals for joint operations and services in which each alliance partner continues to serve its market using jointly operated or used inland feeders,inland terminals, port terminals, and mainline fleets of ship as well as joint pools of containers and equipment. Strategic alliances are generally more formal agreements than consortia and impose longer term and far reaching obligation on their members. It also acts as one in developing and advancing the strategic aims of the alliance members. The most important objective for liner strategic alliances is cost reduction and improvement in capital asset utilization. Main aims of strategic alliance drawn in this paper, can be enumerated follows : 1. improvements in service frequency and quality : 2. improvements in vessel and equipment utilization and thereby reductions in fixed and variable cost ; 3. improvements in market shares and high value cargo booking ; 4. reductions in intermodal storage and port terminal throughput costs ; 5. improvements in negotiating powers with ports and feeder transport providers ; 6. reduction in financial and other fixed costs such as insurance; 7. coordination and integration of MIS and EDI systems and service for greater efficiency and market penetration ; and, 8. improvements in logistic chain management and economic of scale by equipment depot, terminal, and vessel sharing.

• Journal of Broadcast Engineering
• /
• v.25 no.1
• /
• pp.25-35
• /
• 2020

Recently, the development of image processing technology, as well as hardware performance, has been continuing the research on 3D point processing technology that provides users with free viewing angle and stereoscopic effect in various fields. Point cloud technology, which is a type of representation of 3D point, has attracted attention in various fields because it can acquired/expressed point precisely. However, since Hundreds of thousands, millions of point are required to represent one 3D point cloud content, there is a disadvantage that a larger amount of storage space is required than a conventional 2D content. For this reason, the MPEG (Moving Picture Experts Group), an international standardization organization, is continuing to research how to efficiently compress, store, and transmit 3D point cloud content to users. In this paper, a V-PCC bitstream generated by a V-PCC (Video-based Point Cloud Compression) encoder proposed by the MPEG-I (Immersive) group is composed of an MPU (Media Processing Unit) defined by the MMT. In addition, by extending the signaling message defined in the MMT standard, a parameter for a segmented transmission method of the 3D point cloud content by area and quality parameters considering the characteristic of the 3D point cloud content, so that the quality parameters can be selectively determined according to the user's request. Finally, in this paper, we verify the result through design/implementation of the verification platform based on the proposed technology.

• International Journal of Highway Engineering
• /
• v.14 no.3
• /
• pp.151-162
• /
• 2012

It is not surprising to hear news about irresistible natural disasters all over the world due to climate change. Korean Government has focused on developing a variety of green technologies to reduce green house gasses, in particular, carbon dioxide. This study suggested 18 technology divisions for achieving green highway technology development in six different sub-sectors considering life-cycle of roadway and surveyed 29 highway and/or transportation professionals of three institutes using AHP(Analytical Hierarchy Process) analysis to construct "Green Highway"and realize carbon emission reductions and energy use efficiency in a road sector in Korea. Expert Choice Software was used to rank 18 technology divisions weighted by two-level choices. Transport Operating Infrastructure Improvement, Roadway Policy Implementation, Green Transportation(such as Pedestrian and Bicycle) were highly ranked by respondents according to results of the AHP modeling. Among the 18 divisions, technology policy for supporting R&D investments from development to commercialization was ranked as the most significant one to be focused. Green Transportation Facility Design/Construction/Operation and Eco-Friendly Roadway Plan were followed as expected since professionals have thought that the planning/design step of the life-cycle is a starting point to reduce carbon dioxide from roads more and more. Additionally, comparing the results with the Government investment trend 2006-2011 for the roads, it can be interpreted that the Government should invest to the R&D area more widely than before to promote element and core technology development for Green Highway Construction. Above all, small and mid-sized businesses have to be invested as well as encouraged to undertake green highwayrelated objects to accomplish the divisions which ranked high.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.30 no.3
• /
• pp.241-247
• /
• 2012

The national geodetic reference frame of Korea switched to the International Terrestrial Reference Frame (ITRF) in 2003. In order to study the land area changes, we calculated the entire land area of Korea using the administrative boundaries of census data provided by Statistics Korea. The standard transformation procedure by the National Geographic Information Institute (NGII) was followed. The Transverse Mercator (TM) projected coordinates were transformed into the GRS80-based world geodetic reference frame, and the ellipsoidal and the projected areas were calculated. The provinces that range over two projection origins were divided into two polygons and projected using appropriate origins. After the transformation, all boundaries were shifted in the northwestern direction, resulting in a decreased area of $1.36km^2$ (about 0.0013%) on the projected plane. Moving the boundaries into a high latitude area cancels out the effect of the enlarged ellipsoid. In addition, the rate of change shows that a higher-latitude province is more sensitive to the shift of the boundaries. The data by Statistics Korea is significantly different from those of the Ministry of Land, Transport and Maritime Affairs (MLTM), thus it is urgently recommended that the data are integrated and unified.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.37 no.2
• /
• pp.155-165
• /
• 1992

Experiments were conducted to determined the development of the vascular bundles in the peduncle of different tillers on its development in order to improve the vascular system and possibly increase grain yield. The development of the vascular bundle in the leaf, stem and panicle is an important aspect of assimilate translocation and differentiation of panicle characters. Two cultivars were used in this study: IR58, an indica type, and Unbong 7, a japonica type. The main culm(M) had more and bigger vascular bundles in the peduncle and those vascular bundle decreased with tiller order and tiller development. In the primary tillers, P1 had more large and small vascular bundles than P5 in both cultivars. IR58 developed more large vascular bundles compared to Unbong 7, but the small vascular bundle in unbong 7 was more than in IR58. The cross sectional area of phloem and xylem in large vascular bundle decreased with tiller order in both cultivar. Larger area of phloem and xylem in the early formed tillers more efficient transport of assimilates. The number of spikelets, the weight of panicle and grain yield per panicle were highest in the main culm followed by the order of their initiation or emergence. The number of primary and secondary branches to be positive associated with the number and area of vascular bundles. Furthermore, the number of vascular bundles in the peduncle was highly correlated with the peduncle thickness which in turn was correlated with the number of primary and secondary branches on the panicle. These results showed tillers that are initiated early and have relatively ation usually have more vascular bundles, larger peduncle, more spikelets spike let filling and ultimately higher yield.

• Journal of Korea Port Economic Association
• /
• v.31 no.3
• /
• pp.141-153
• /
• 2015

This paper is an attempt to analyze the comparative advantage of Busan Port to China. For this, we use the market comparative advantage index, which is a version of the revealed comparative advantage index. The market comparative advantage index (MCA) uses trade patterns to identify the sectors in which a region has a comparative advantage, in this case by comparing Busan Port's trade profile with the world average (China). The indices are calculated at the commodity level of the HS four-digit classification. The export data used in this study are obtained from the Korea International Trade Association. Exports to China accounted for almost one third of Korean exports in 2014. There are, however, structural differences among the main export items of Busan Port. This paper, therefore, employs MCA indices to reveal the behaviors of the ten main export items, which are "HS3920-other plates/sheets/film/foil of plastics," "HS7606-aluminum plates/sheets/strip," "HS8479-unspecified machines/medical appliances," "HS8486-machines for semiconductor devices or wafers," "HS8529-parts for transmission apparatus for television," "HS8703-motor vehicles for the transport of persons," "HS8708-parts of motor vehicles," "HS9001-optical fibers," and "HS9013-liquid crystal devices." The study shows that export competitiveness of nine items increases, the exception being HS8703. However, China's import ratios of seven of the nine items for which the MCA indices go up are on the decrease, which means that it would be hard to expand the export market for these seven items, despite the higher MCA indices. Since the shares of the port's total exports to China of HS3907, HS8486, HS8529, HS9001, and HS9013 in total exports to China increase together with China's import ratio decreasing, these items may have promising export markets. MCA increases of HS7606 and HS8479 are attributable to China's lower import ratio, rather than a higher export share, so higher MCA indices do not guarantee higher export competitiveness for these items.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.232-239
• /
• 2001

Young Jong Grand Bridge is approach traffic road of New Inchon International Airport which covers hub airport function in northeast asia. The total span length of this bridge is $4,420{\cal}m$ and this main bridge type is, the first in the world, Double Deck Self Anchored Suspension Bridge, designed as double deck systems to be arranged by road and railroad. Approach bridges to be connected with main span also are composed double deck steel truss and steel box girder to consider a continuity with this span. Our company erected $1,375{\cal}m$(about 60,000tons) of double deck steel truss bridge type which is composed by 6 traffic lane on upper deck and 4 traffic lane and Double track railroad on lower deck. The original installation method of this bridge was planed to install about 75 meters bridge blocks to use floating crane, after temporary bent was constructed between permanent piers. But this method which had to construct many temporary bents in the sea had the matter that construction periods can become lengthen and construction cost can be risen. To overcome the uncertainty to ensure high qualify of bridge and economic project execution, our company developed new bridge erection method to assure both quality control and economic construction work. The new erection method which was developed by us was one that could transport and install long bridge block, $120{\cal}m$ unit at a time and that temporary bent was not required. We hope that this paper is used as technical data which will erect bridge in the western sea and others marine region.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.18 no.2
• /
• pp.167-174
• /
• 2012

Transport of marine debris between countries is a potential source of diplomatic conflicts. U-i Island in Shinan County, Jeonnam Province has been reported by media as being damaged by marine debris from foreign countries. However, scientific researches on those marine debris have not been published. So, the features of foreign marine debris on Seongchon Beach in U-i Island were surveyed on Feb. 2012. The ratio of marine debris from foreign countries was 34.7% by number of items, 56.3% by weight, and 48.5% by volume in $200m^2$ transacts. Most of them, 98.9% in number, were inferred to be originated from China. The most abundant items were plastic beverage bottles and black floats. The total number of black floats was 539 within the 1,100m beach. Fifteen of them had information on manufactured locations, of which 87.6% were Liaoning Province in northern China. As domestic policy cannot prevent the inflow of the marine debris from foreign countries, countermeasures should be sought out from the international cooperation with the neighboring countries. For the black floats, recycling method should be developed as lots of the same types of black floats are drifted ashore in winter. And, as the U-i Island is a National Park with its valuable natural heritages, methods should be designed to minimize impacts on dune topography and ecology.