• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.6
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• pp.97-107
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• 2013

On the Staggered Crosswalks, pedestrians cross the crosswalks two times. This method can reduce the cycle, the vehicle delay and the walking distance by increasing the major direction of green time. The safety of pedestrians is also effective. This study suggests the warrant of the facilities of island width and length etc. by considering the road structure and pedestrians. Also this study suggests the standard of the safety through the accident analysis of Staggered crosswalks and General Crosswalks. In the results, accident rate of the Staggered Crosswalks 18.3(100 million vehicle-km) was lower than the accident rate of the General Crosswalks 28.3(100million vehicle-km). By understanding the start point of crossing of the Staggered Crosswalks, the analysis of the location and types of accident suggests the safety zone(spare space). The setting warrants of Staggered Crosswalks are 4 lane over the road and the 2 meter over sidewalk width of island. The minimum length of the Pedestrian island was doubled compared to the crosswalks width. And the maximum length was set by considering the wait time of the pedestrians.

• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.441-449
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• 2015

This study was conducted to screen the characteristics of external and cranial characters of Crocidura shantungensis collected from Korean Peninsula, Ulleung Island and Jeju Island. There were significant differences in head-body length (HBL), tail length (TL), ear length (EL), and hind foot length (HFL) in males and HBL, TL, and HFL in females among three populations (p<0.05). The HBL and TL in the Jeju Island population were larger (8.0 mm and 4.0 mm in lengths, respectively) than those of the Korean Peninsula population. Based on skull analysis, a total of thirteen traits showed significant differences among the three populations (p<0.05). The condylo-insicive length (CIL), maximum width of brain case (MWB), mandibular length (ML), and mandibular height (MH) in the Jeju Island population were significantly larger than those of Korean Peninsula population (p<0.05). Principle component analysis (PCA) showed that two principle components (PC) identified from the PCA affected on the body size and width of the skull, respectively. Discriminant analysis revealed that these populations could be discriminated through skull traits. These findings concluded that the Jeju Island population was greater in the size than the Korean Peninsula, suggesting that the Jeju Island shrews have successfully adapted to the island environments and they had morphologically differentiated during glacial period after natural immigration into that Island. Thus, this study supports the 'Island Rule', showing that the population is well adapted to the island environments. This may provide important information for biogeographical and ecological studies on insular animals.

• International Journal of Highway Engineering
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• v.16 no.2
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• pp.99-106
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• 2014

PURPOSES : This study is to develop Right-Turning Channelization Design Models of Semitrailer at Intersections by regression of vehicle tracking simulation. METHODS : Based on the literature review, it was indicated that right-turning channelization design guide of semitrailer is too complex and is not reflected turning speed and approach angle. To verify effectiveness of right turning semitrailer trajectories according to the changing turning speed and approach angle, vehicle tracking simulation was executed. And then, simulation results were analyzed for modeling design elements; minimum turning radius, swept path width, arc length, width of triangle island, of right-turning channelization using regression methods. RESULTS : When the turning speed is getting higher, minimum turning radius, arc length, width of triangle island increased and the approach angle lower, swept path width, arc length, width of triangle island reduced. The turning radius completely reflected by turning speed. CONCLUSIONS : In this research, it was investigated how much design elements are changed according to the turning speed and the approach angle of semitrailer. The developed right-turning channelization design models can help engineers to easy and comfortable design at various conditions.

• The Korean Journal of Malacology
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• v.26 no.3
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• pp.227-234
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• 2010

A comparative analysis of size and age structures of coastal subfossil shell assemblages of the shortnecked clam Ruditapes philippinarum from open and protected bays of Cheju Island (Korea) was carried out. On the whole, taking into account the damage of small fragile shells, size and age structures of the shell assemblages corresponded to the classical curve of bivalve population distribution when its mortality diminishes with age increase up to a certain threshold. It was found that shell samples from open bays of the western, southern and eastern coasts included shells of smaller and younger individuals (L ${\leq}$ 40 mm, ${\leq}$ 4 years) than samples from the eastern protected bay (L ${\leq}$ 54.5 mm, ${\leq}$ 6 years). Evidently, strong wave activity was the reason for a short life-span of the clams from the open areas. Growth was investigated retrospectively by annual growth rings on the shells. Growth rates of the clams from the various coasts of Cheju Island differed. However, growth rates of the clams from different biotopes at the same (eastern) side of the Island were similar. Shell height/length and width/length ratios statistically significantly increased with the clam age increase. Most likely, the reason for such shell shape alteration is that more conglobated individuals more survive being more energy-optimal than oblong specimens.

• Journal of Environmental Science International
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• v.22 no.7
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• pp.895-903
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• 2013

This study analyzed on characteristics of the ground-water capture zone in coastal areas and mid-mountainous area according to pumping rate. For this study, it targeted Jejudo island where is the volcanic island. To analyze, MODFLOW model and MODPATH model, which are the ground-water flow analysis models, were used. As a result of research, the following conclusions could be obtained. As a result of analyzing influence of a change in pumping time upon length of capture zone, the length of capture zone in coastal area was indicated to be greater in the changing ratio compared to the length of capture zone in mid-mountainous area. Next, in the coastal area, the pumping rate and the capture-zone length are changing similarly. However, in mid-mountainous area, the length of capture zone was indicated to grow when the pumping rate comes to exceed 1,500m3/day. As a result of analyzing influence of a change in pumping time upon capture area, the tendency of a change in the area was indicated similarly in coastal areas and mid-mountainous area. Especially, it could be known that the larger pumping rate leads to the more definite increase in tendency to a change in capture area. Based on this study, it was allowed to be possibly used in the suitable pumping rate in coastal areas and mid-mountainous area of the volcano island in the future. A follow-up research is judged to necessarily analyze the influence of tubular-well group upon capture zone by additionally analyzing a change in capture zone targeting the concentrated tubular well.

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.127-130
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• 2005

The early stage of the self assembly for octadecyltrichlorosilane (OTS)-based monolayers is investigated using atomic force microscopy (AFM). Height measurements using AFM prove that the island height of the monolayers gradually increases with increasing the island size, and is close to the limiting value (h = $\sim$25 $\AA$) after d = $\sim$600 nm in size. Since the theoretical length of a covalently bound OTS molecule is 26.2 Å, the limiting value of the island height means that the islands with d ${\geq}$ 600 nm consist of close-packed, fully extended chains. The heights for the islands with d < 600 nm are lower than the limiting value and decrease with decreasing the island sizes. This observation indicates that the OTS molecules in the small islands are less densely packed, and that the packing densities of the islands increase as the islands grow in size.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.6
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• pp.629-635
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• 2014

This paper presents annual energy production (AEP) by a 1.5kW wind turbine due to be installed in Deokjeok-Do island. Local wind data is determined by geometric shape of Deokjeok-Do island and annual wind data from Korea Institute of Energy Research at three places considered to be installed the wind turbine. Numerical simulation using WindSim is performed to obtain flow pattern for the whole island. The length of each computation grid is 40 m, and k-e turbulence model is imposed. AEP is determined by the power curve of the wind turbine and the local wind data obtained from numerical simulation. To capture the more detailed flow pattern at the specific local region, Urumsil-maul inside the island, fine mesh having the grid length of 10m is evaluated. It is noted that the input data for numerical simulation to the local region is used the wind data obtained by the numerical results for the whole island. From the numerical analysis, it is found that a local AEP at the Urumsil-maul has almost same value of 1.72 MWh regardless the grid resolutions used in the present calculation. It is noted that relatively fine mesh used for local region is effective to understand the flow pattern clearly.

• Ocean and Polar Research
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• v.26 no.1
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• pp.1-10
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• 2004

Ice cliff retreat and sea-ice formation around King Sejong Station in King George Island were analysed and compared with air temperature change. Analysis of 33-year (1969-2001) air temperature records at Bellingshausen Station has revealed regional atmospheric warming, and the increasing rate of air temperature Is equivalent to a warming of $1^{\circ}C$ for 27-year period. Here we present time-series of observations for the areal extent of the ice cliff and ice sheet, showing that they have retreated dramatically in the past 45 years (1956-2001). Retreat of 1,050 m in length of the ice clifr has changed the Marian Cove into a low rectangular form of 4 km in length and 1 to 1.3km in width. The retreat rates have since increased from 6 m/yr of the Primary investigated Period to 54 and 81m/yr in the recent years. Exceptionally, the ice cliff had been advanced of 21m in length for a year between 1987 and 1988 of cold winters. Ice sheet in King George Island also shows a similar decrease, and the decreasing extent is much larger at the southern part of the Main Cove, relatively more exposed to the sun, than at the northern part. Comparing sea-ice formation in winter with air temperature data shows a pattern starting to freeze below $-5^{\circ}C$ and to thaw over $-3^{\circ}C$. It is conclusively estimated that the patterns and magnitudes of ice cliff retreat and sea-ice formation are consistent with fluctuations of the air temperature, and that the recent rapid retreat of ice cliff and less formation of sea-ice are caused especially by the warming trends in autumn accompanied with expansion of summer thawing period.

• Korean Journal of Environment and Ecology
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• v.30 no.1
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• pp.39-47
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• 2016

Recently, it has been reported that morphologically and genetically different two Siberian roe deer (Capreolus pygargus, Pallas, 1771), in Mainland and in Jeju island. Until now, this roe deer has not been clearly taxonomy of Siberian roe deer in Korean peninsula. So, the aim of this study was to compare the skull morphometrics of mainland and Jeju roe deer to obtain more information on the species status of C. pygargus and study the distribution of roe deer subspecies in this region. A total of 50 skulls of adult roe deer was compared and analyzed. The maximum skull length, condylo-basal length, basilar length, maximum skull width, cheek-bone width, interorbital width, rostrum length, length of upper tooth row from the Siberian roe deer in Jeju island were significantly smaller than those of the deer in mainland. Length of the skull was the principal factor of interpopulational variability in roe deer. Variation was not distributed along latitude, longitude, or elevation, but those factors did influence the variation through effects on primary production, which in turn caused isolated differences in skull morphology apparently related to types of forage selected by roe deer in various geographic areas. According to the analysis results of the skull characters, Mainland roe deer was more similar to C. p. tianschanicus which is a subspecies of Siberian roe deer. In addition, Jeju roe deer showed distinct differences compared to European roe deer, 3 subspecies of Siberian roe deer, so it appeared that they could be a unique native species inhabited only in Jeju Island. Because Siberian roe deer in Jeju Island can be classified at subspecies level in this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.183-192
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• 1994

Spatial distribution patterns of Antarctic krill, Euphausia superba in the Atlantic Ocean sector were seasonally divided into three or four regions; South George Island, Laurie/Coronation Islands and Livingston/King George Islands. Antarctic krill were caught from the surface to about 150 m in depth. The vertical distribution of catch per hour (CPUE) did not show much differences between the 10 m layers, but there were gradually poorer CPUEs as trawl depth increased. It was estimated from relationship between water temperature and CPUE that the Antarctic krill abundance was maximal at water temperatures of $0.8{\sim}1.0^{\circ}C$. The length compositions of Antarctic krill showed that female fish were, on an average, significantly larger than males. Relationship between carapace length and body length, and body length-body weight relationship were well fitted. Sex ratio was $60.3\%$ for male and $39.7\%$ for female with significant difference at the $5\%$ level.