• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.269-281
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• 2018

Unlike its archetype predecessor such as the Highway Capacity Manual of the United States, the Korean Highway Capacity Manual of 2013 provides the analytical models for estimating the saturation flow rates for the lane-occupying work-zones in the proximity of the signalized intersections. Direct application of the revised saturation flow rates into the classic control delay models, however, appears to produce unreasonable delay amount as traffic demand approaches lane-group capacities and surpasses them, which is common phenomena in the work-zones. Complex interaction among vehicles, lane-dropping work-zone geometry and signal operations were never accounted in the traditional control delay models, and considerable differences between the delay model outcomes and field observations are repeatedly experienced. This paper proposes the modified approaches to the delay models in the manual, exerted on all three elements of control delay, and particularly focuses on the temporal and spatial boundary expansion in comparing the simulated results to the estimated ones. Extensive microscopic simulation work and calibration effort supports the modified approaches well enough to use them in the work-zone planning and evaluation.

• Journal of the Korean association of regional geographers
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• v.19 no.3
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• pp.384-400
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• 2013

In this study, spatio-temporal patterns of extreme precipitation events caused by typhoons are examined based on observational daily precipitation data at approximately 340 weather stations of Korea Meterological Administration's ASOS (Automated Synoptic Observation System) and AWS (Automatic Weather System) networks for the recent 10 year period (2002~2011). Generally, extreme precipitation events by typhoons exceeding 80mm of daily precipitation commonly appear in Jeju Island, Gyeongsangnam-do, and the eastern coastal regions of the Korean Peninsula. However, the frequency, intensity and spatial extent of typhoon-driven extreme precipitation events can be modified depending on the topography of major mountain ridges as well as the pathway of and proximity to typhoons accompanying the anti-clockwise circulation of low-level moisture with hundreds of kilometers of radius. Yellow Sea-passing type of typhoons in July cause more frequent extreme precipitation events in the northern region of Gyeonggi-do, while East Sea-passing type or southern-region-landfall type of typhoons in August-early September do in the interior regions of Gyeongsangnam-do. These results suggest that when local governments develop optimal mitigation strategies against potential damages by typhoons, the pathway of and proximity to typhoons are key factors.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.516-525
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• 2011

We studied the influence certain environmental factors (proximity of roosting site, roads, and residential areas) have on the spatial distribution of cranes in the Cheorwon, Korea. Using a range finder and GPS, data were collected from January to February 2007 and were subsequently evaluated with ArcGIS. The size of the cranes' wintering habitat was estimated to be 7$76.9km^2$. Five hundred and fifty-five flocks of cranes were observed and detailed distributions were collected. Feeding distribution of the cranes showed clustered distribution, however, no tendencies of spatial autocorrelation were apparent. Adjacent regions with paved roads and residences showed lower densities than other areas. Distances at which paved roads and residential areas induced changes in feeding flock densities were 1500m and 1750m, respectively. Feeding flock density decreased with increased distance from roosting site. Feeding flock density of the two crane species did not increase as distance from roads increased, however, the density of individuals showed a significant increasing tendency with increased distance from roads. In both species, density of feeding flocks and individuals significantly increased with increasing distance from residential areas. In Red-crowned Cranes, the density of feeding flocks and individuals significantly decreased with increasing distance from roosting site, however, in the case of White-naped Cranes, there was an even distribution in density of feeding flocks and individuals.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.14-25
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• 2018

The operation of high-speed rail (HSR) has an effect on the agglomeration economies, and the impact is shown as a relocation of individual firm and worker to where business activity can be maximized. The proximity to the HSR station could be considered as a core district to maximize the industrial benefit through the HSR network. From this perspective, this study considers the agglomeration effect of HSR within the HSR station-area and analyzed the agglomerated spatial pattern through hotspot analysis by service industry in the cases of Korea and Japan using GIS. This study analyzed the service industry within 1km distance from 8 HSR stations of Korea and 4 Kyushu Shinkansen stations of Japan. The results suggest that the hotspot patterns are observed in the service industry within 1km distance from the HSR station of Korea and Japan, except for two HSR stations of Gupo station and Kagoshima-Chuo station. Leisure, amusement, association, and other specific service industries could be affected by HSR passengers and knowledge-spillovers through HSR station. Therefore, the observed hotspot districts near the HSR station-area could explain an agglomeration pattern of the service industry through a closeness to the HSR station. Further, we could expect that the impact of HSR affects the service industry, and the impact could attract business activities of the service-area to maximize their benefit from HSR travelers. With the result, it is required to build up a supportive policy to maximize the HSR's impact on the service industry when considering the HSR station-area development.

• Economic and Environmental Geology
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• v.51 no.5
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• pp.409-428
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• 2018

Yeongdong area is located on the border zone between Precambrian Yeongnam massif and central southeastern Ogcheon metamorphic belt, in which Cretaceous Yeongdong sedimentary basin exists. Main geology in this area consists of Precambrian Sobaeksan gneiss complex, Mesozoic igneous and sedimentary rocks and Quaternary alluvial deposits. Above this, age-unknown Ogcheon Supergroup, Paleozoic sedimentary rocks and Tertiary granites also occur in small scale in the northwestern part. This study focuses on the link between the various geology and Rn concentrations in groundwater. For this, twenty wells in alluvial/weathered zone and sixty bedrock aquifer wells were used. Groundwater sampling campaigns were twice run at wet season in August 2015 and dry season in March 2016. Some wells placed in alluvial/weathered part of Precambrian metamorphic rocks and Jurassic granite terrains, as well as Cretaceous porphyry, showed elevated Rn concentrations in groundwater. However, detailed geology showed the distinct feature that these high-Rn groundwaters in metamorphic and granitic terrains are definitely related to proximity of aquifer rocks to Cretaceous porphyry in the study area. The deeper wells placed in bedrock aquifer showed that almost the whole groundwaters in biotite gneiss and schist of Sobaeksan gneiss complex and in Cretaceous sedimentary rocks of Yeongdong basin have low level of Rn concentrations. On the other hand, groundwaters occurring in rock types of granitic gneiss or granite gneiss among Sobaeksan gneiss complex have relatively high Rn concentrations. And also, groundwaters occurring in the border zone between Triassic Cheongsan granites and two-mica granites, and in Jurassic granites neighboring Cretaceous porphyry have relatively high Rn concentrations. Therefore, to get probable and meaningful results for the link between Rn concentrations in groundwater and surrounding geology, quite detailed geology including small-scaled dykes or vein zones should be considered. Furthermore, it is necessary to take account of the spatial proximity of well location to igneous rocks associated with some mineralization/hydrothermal alteration zone rather than in-situ geology itself.

• Asian Journal of Atmospheric Environment
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• v.9 no.1
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• pp.57-65
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• 2015

We measured the concentrations of five aromatic hydrocarbons (benzene, toluene, ethylbenzene, m,p-xylene, and styrene) in the atmosphere during four seasonal campaigns at Deokjeok and Jeju Islands in the Yellow Sea from October 2005 to June 2006. Toluene was the most abundant aromatic hydrocarbon, with median of 0.24 ppb at Deokjeok and 0.20 ppb at Jeju, followed by benzene (0.21 ppb, 0.15 ppb) and m,p-xylene (0.06 ppb, 0.06 ppb). Aromatic hydrocarbon measurements exhibited the typical seasonality of the major emission sources, such as vehicle exhaust, solvent evaporation, and regional circulation patterns. The ratios of m,p-xylene/ethylbenzene of 1.57 at Deokjeok and 1.05 at Jeju reflected the degree of proximity to outflows of each source region, South Korea and China. The toluene/benzene ratios of 1.0 were consistently both on field observations and on the 3-D chemical model simulation, which is slightly higher than that in the Western Pacific area. It implied that the air over the Yellow Sea was influenced to a great extent by the surrounding areas. We confirmed that current emission inventories of aromatic hydrocarbons in Northeast Asia reasonably reproduced temporal and spatial variations of toluene and benzene over the Yellow Sea.

• Journal of the Korean association of regional geographers
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• v.10 no.2
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• pp.356-370
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• 2004

New communication and information technologies such as the Internet are space-adjusting technologies. The Internet changes the spatial proximity by improving the connections between people and organizations separated by geographical distance This paper examines the digital position of individual nation-states on a global cyberspace. The number of inter-domain hyperlinks embedded in websites for 47 nations was gathered using the AltaVista in 2001 Data were also obtained on the geographical distance among the nations. The results indicate that the u.s. is the most central nation on the global cyberspace, followed by the U.K., Germany, Australia, Canada, Italy, France, China and Japan. The most peripheral nations are Uruguay, Luxemburg, and UAE. It also examines the relationship between the digital positions of 47 nations and their physical locations. The results indicate that digital structure on the cyberspace is not significantly related to geographical distance among those nations.

• Journal of Korea Multimedia Society
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• v.13 no.8
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• pp.1128-1141
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• 2010

This paper proposes a method of moving object detection in crowded scene using clustered trajectory. Unlike previous appearance based approaches, the proposed method employes motion information only to isolate moving objects. In the proposed method, feature points are extracted from input frames first and then feature tracking is followed to create feature trajectories. Based on an assumption that feature points originated from the same objects shows similar motion as the object moves, the proposed method detects moving objects by clustering trajectories of similar motions. For this purpose an energy function based on spatial proximity, motion coherence, and temporal continuity is defined to measure the similarity between two trajectories and the clustering is achieved by minimizing the energy function in CRFs (conditional random fields). Compared to previous methods, which are unable to separate falsely merged trajectories during the clustering process, the proposed method is able to rearrange the falsely merged trajectories during iteration because the clustering is solved my energy minimization in CRFs. Experiment results with three different crowded scenes show about 94% detection rate with 7% false alarm rate.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.5 s.112
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• pp.15-30
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• 2005

A deserted town once vibrant with active commercial activities around a railroad station now tries to find a way to escape from depression and revive its life with a renewed civic pride. An open space adjacent to the Main Street, the commercial district of Buzzards Bay, Massachusetts, is waiting to be transformed and reconfigured to be a new ecological park to boost the economy of the community. Bridge Park is 26-acre land abutting the Cape Cod Canal with a railroad bridge as a backdrop. The existing condition of the site with a small salt marsh, woodland, lawn, and the vestige of old railroad easement along with the proximity to the commercial district poses an interesting question of how to make a medium scaled ecological park within an urban context. This paper examines the winning design proposals for the Bridge Park submitted to the International Design Competition held in April, 2005. Six winning proposals were introduced and discussed in terms of categories related to the trend of contemporary landscape design such as; 1) ecological ordinariness and geometric figures, 2) topography and spatial imagination, 3) minimal programs and open put 4) time and process oriented design, 5) park and economic effects and 6) diagrammatic plan and photo montage. Bridge Park Design Competition confirms the complex characteristics representing the contemporary landscape design overcoming the dichotomy between nature and culture and the 'pastoral ecological design' and 'landscape as an art'. The Park becomes the activating agent for the community rejecting the conventional and passive role as a romantic picturesque landscape. Bridge Park International Design Competition is a meaningful event to test the idea of new ecological urban park, and to fine-tune the trend of the contemporary urban park design.

• Journal of the Economic Geographical Society of Korea
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• v.15 no.4
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• pp.628-641
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• 2012

This research investigates a dynamic mechanism underlying the co-evolution between network and space by applying hype-curve model, typical phenomenon which shows how new technologies and ideas initially adapted in the society. This study analysis the knowledge intensive industry of digital contents using social network analysis (SNA) in terms of structural, spatial, and temporal aspects, year of 2000, 2005, and 2010 focused on Seoul area. First of all, network and space establish 'inter-feedback' as a result of evolution and differentiation process. Second, it happen temporal 'delay' through the learning process stage of 'peak of inflated expectation' and 'trough of disillusionment.' As a result, Seoul develops with the technology commercialized-orient strategy affect government policy. This trend changes to technology-oriented development in Seoul area in the late of 2000 established 'self-organization' with geographical proximity organizations through learning process.