• Journal of the Korean Society for Railway
• /
• v.12 no.4
• /
• pp.488-498
• /
• 2009

The characteristics of intercity rail network are different from those of public transit network in urban area. In this paper, we proposed a new transit assignment model which is generalized form of deterministic assignment model by introducing line selection probability on route section. This model consider various characteristics of intercity rail and simplify network expansion for appling search algorithms developed in road assignment model. We showed the model availability by comparing with existing models using virtual networks. The tests on a small scale network show that this model is superior to existing models for predicting intercity rail demand.

• Journal of Korea Port Economic Association
• /
• v.35 no.3
• /
• pp.125-150
• /
• 2019

The Hunchun area is the only development and opening line in Jilin Province and the Changchun-Jilin-Tumen Developmental Plan area, and as a hub area for regional logistics, promoting the logistics competitiveness of the Hunchun area is an important factor in promoting economic development in the Northeast region. The purpose of this study is to derive the factors for activating logistics competitiveness in Hunchun area by applying SWOT analysis and to present them to policy-makers by drawing priority of factors for promoting logistics competitiveness in Hunchun area through AHP survey of Chinese and Korean logistics experts. According to the analysis, the weighting was high in order of opportunity factors and strength factors, and the priority was high in order of factors such as promotion and expansion of One Belt, One Road policies, active support through national policies, construction of international logistics center cities, construction of logistics centers, and supply of bulk cargo. Finally, from a comprehensive perspective, this study presented policy implications such as SO Strategy (Strength-Occupancy Strategy) and ST Strategy (Strength-War Strategy) focusing on the strengths of the Hunchun Region for the strategy of strengthening the logistics competitiveness of the Hunchun area.

• Journal of the Korean association of regional geographers
• /
• v.8 no.1
• /
• pp.40-64
• /
• 2002

The locational characteristics of ceramic industry in Miryang city, Kyongnam province, were clarified by means of examining the process of its formation, spatial variation, locations and their changes. The government policy on industry and the business fluctuation are important in the quantitative changes of the industry. The spatial variation of industry toward the outer part of area are the results of equilibrium between the decrease of firms in inner city and the increase of firms in outer part. The births and deaths of firms played important role in the processes of spatial variations. The industry location has lasted by the accumulation of location decision of 'potential entrepreneurs' who learned knowledges on the industry and had personal contacts with the business-related persons for long time. The main factors on the locational decision of firms are personal factor, raw materials, land, water and market. The locational problems have mainly related with plant expansion, land, marketing, labour and capital. They caused investment changes and caused relocations of firms. Such disadvantages as raw material exhaustion, shortage of land and congestion within the agglomeration area, development of road transportation and local government policy on industry location, induced recent decentralization of industry to outer part.

• International Journal of Highway Engineering
• /
• v.12 no.3
• /
• pp.1-8
• /
• 2010

This study is performed to evaluate the physical and mechanical characteristics of an acryl polymer concrete that is developed as an overlay material for cement concrete slabs and pavements. Various laboratory tests including viscosity, flow, compressive strength, flexural strength, tensile strength, linear shrinkage, thermal expansion and thermal compatibility tests are performed. It is observed from the laboratory tests that the acryl polymer concrete developed in this study satisfies all the requirements suggested by ACI guideline. In addition to the laboratory tests, an accelerated performance testing (APT) is conducted to validate the performance of the acryl polymer concrete. During the APT, no significant distresses are observed until 15,903,939 cycles of equivalent single axle loading is applied. Finally, a 10mm thick overlay with the acryl polymer concrete is applied on top of an old deteriorated concrete pavement to evaluate field performance. Right after the field construction, skid resistance, noise and roughness are measured. The skid resistance and noise level have been significantly improved while the roughness is increased. Periodic investigation for the field study section will be conducted to evaluate the long-term performance.

• International Journal of Highway Engineering
• /
• v.15 no.1
• /
• pp.23-36
• /
• 2013

PURPOSES: The problem under this circumstance is that the erosion not only drops strength of the steel dowel bar but also comes with volume expansion of the steel dowel bar which can reduce load transferring efficiency of the steel dowel bar. To avoid this erosion problem, alternative dowers bars are developed. METHODS: In this study, the bearing stresses between the FRP tube dowel bar and concrete slab are calculated and compared with its allowable bearing stress to check its structural stability in the concrete pavement. These comparisons are conducted with several cross-sections of FRP tube dowel bars. Comprehensive laboratory tests including the shear load-deflection test on a full-scale specimen and the full-scale accelerated joint concrete pavement test are conducted and the results were compared with those from the steel dowel bar. RESULTS: In all cross-sections of FRP tube dowel bars, computed bearing stresses between the FRP tube dowel bar and concrete slab are less than their allowable stress levels. The pultrusion FRP-tube dowel bar show better performance on direct shear tests on full-scale specimen and static compression tests at full-scale concrete pavement joints than prepreg and filament-winding FRP-tube dowel bar. CONCLUSIONS: The FRP tube dowel bars as alternative dowel bar are invulnerable to erosion that may be caused by moisture from masonry joint or bottom of the pavement system. Also, the pultrusion FRP-tube dowel bar performed very well on the laboratory evaluation.

• International Journal of Highway Engineering
• /
• v.15 no.1
• /
• pp.1-9
• /
• 2013

PURPOSES: The purpose of this study is to evaluate physical properties, durability, fatigue resistance, and long-term performance of poly-urethane concrete (PU) which can be possible application of thin layer on long-span orthotropic steel bridge and to check structural stability of bridge structure. METHODS : Various tests of physical properties, such as flexural strength, tensile strength, bond strength and coefficient of thermal expansion tests were conducted for physical property evaluation using two types of poly urethane concrete which have different curing time. Freezing and thawing test, accelerated weathering test and chloride ion penetration test were performed to evaluate the effect of exposed to marine environment. Beam fatigue test and small scale accelerated pavement test were performed to assess the resistance of PU against fatigue damage and long-term performance. Structural analysis were conducted to figure out structural stability of bridge structure and thin bridge deck pavement system. RESULTS: The property tests results showed that similar results were observed overall however the flexural strength of PUa was higher than those of PUb. It was also found that PU materials showed durability at marine environment. Beam fatigue test results showed that the resistances of the PUa against fatigue damage were two times higher than those of the PUb. It was found form small scale accelerated pavement test to evaluate long-term performance that there is no distress observed after 800,000 load applications. Structural analysis to figure out structural stability of bridge structure and thin bridge deck pavement system indicated that bridge structures were needed to increase thickness of steel deck plate or to improve longitudinal rib shape. CONCLUSIONS: It has been known that the use of PU can be positively considered to thin layer on long-span orthotropic steel bridge in terms of properties considered marine environment, resistance of fatigue damage and long-term performance.

• Journal of the Korean Regional Science Association
• /
• v.37 no.3
• /
• pp.47-58
• /
• 2021

In 2010, Busan Metropolitan City established an organization dedicated to urban regeneration. The Sanbok Road Renaissance Project and Hope Village Project are representative urban regeneration projects. Busan Metropolitan City is a leading local government that has expanded community business through urban policies. This study analyzed the operational status and characteristics of community-based community businesses based in Busan Metropolitan City in the early stages of urban regeneration policy. As a result, the direction of community-based community business is 'community empowerment'. However, the project effects such as 'expansion of opportunities for local residents to help each other' and 'residents' understanding of the local community' were low. In order to operate a community business, it is important to secure sufficient business capital and secure necessary human resources. In order to revitalize community-based community businesses through urban regeneration policies, it is necessary to convert support into functional organizations of urban regeneration projects rather than expanding subsidies and expand opportunities for business participation.

• Journal of the Korean Institute of Gas
• /
• v.25 no.5
• /
• pp.19-29
• /
• 2021

Due to the climate changing, the world's countries are tightening regulations on CO2 and air pollutants emission to solve them. In addition, eco friendly vehicles is increasing to replace automobiles in internal combustion engine. Recently, the government is supporting the expansion of hydrogen refueling infrastructure and localization of core equipment in refueling facilities according to the hydrogen economy road map. In this study, design of the Excess flow limiting device in FCEV cylinder valve using by finite element analysis and performed performance tests on prototype. Major test results as hydrostatic strength, continued operation, operation, pressure impulse, leakage showed that the excess flow limiting device meets the performance requirements according to ISO 12619-2 and ISO 12619-11.

• Journal of Climate Change Research
• /
• v.9 no.3
• /
• pp.223-234
• /
• 2018

Estimation of future land cover based on climate change scenarios is an important factor in climate change impact assessment and adaptation policy. This study estimated future land cover considering Shared Socioeconomic Pathways (SSP) using Scenario Generators. Based on the storylines of SSP1-3, future population and estimated urban area were adopted for the transition matrix, which contains land cover change trends of each land cover class. In addition, limits of land cover change and proximity were applied as spatial data. According to the estimated land cover maps from SSP1-3 in 2030, 2050, and 2100, respectively, urban areas near a road were expanded, but agricultural areas and forests were gradually decreased. More drastic urban expansion was seen in SSP3 compared to SSP1 and SSP2. These trends are similar with previous research with regard to storyline, but the spatial results were different. Future land cover can be easily adjusted based on this approach, if econometric forecasts for each land cover class added. However, this requires determination of econometric forecasts for each land cover class.

• Convergence Security Journal
• /
• v.20 no.5
• /
• pp.81-88
• /
• 2020

China, since the early days, according to their ideology, neighboring countries and their citizens were under their sphere of power. This means that only the Hanzu are real native Chinese and the other minor ethics groups are technically immigrants. The People's republic of china, part of the chinese communist party, has had rapid economic growth after Deng Xioping took over and implemented various expansionist policies and reforms, opening china to the world. Internally, the minority ethnic groups were forcibly relocated to specific regions, prohibited from using their native languages, and their culture was absorbed or incorporated into the Hanzu culture in an attempt to internally suppress or erase them. Externally, various projects such as the 'Xia-Shang-Zhou Chronology Project', 'Origins of Chinese Civilization Project', 'Northeast Project', 'Northwest Project', and the 'Southwest Project' were implemented to spread their culture and history to neighboring countries in an attempt to expand their territory. In addition, as capitalism spreads throughout china through reforms and its expansion, it has pioneered the one belt one road aiming to secure as safe transit and raw materials, expand their military facilities, and expand their export market. By doing so, China is infringing on other countries' politics, economy, and borders, and as a result there is a need for Korea to also reexamine its policies in all fields related to china such as politics, economy, history, and culture.