• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2019.11a
• /
• pp.9-10
• /
• 2019

서울시 첫 번째 경전철인 우이신설선은 2017년 9월 개통 이후 대중교통 불모지인 서울 동북부지역의 중요한 교통축을 담당하고 있다. 일평균 약 8만 명이 이용하는 우이신설선은 통행시간의 획기적인 개선과 지역 활성화에 기여하는 등 긍정적 효과가 있으나 개통 2주년이 지난 현재 출퇴근시 혼잡도 문제가 심화되는 등 대시민 서비스 측면에서의 쟁점도 제기되고 있다. 본 논문은 우이신설선 사례를 기반으로 서울시 경량전철 통행특성을 분석하고 첨두시 혼잡원인을 파악하여 계획단계부터 혼잡도를 고려한 시설설계 개선방안 등을 제시하였다. 통행특성 및 혼잡원인 분석은 우이신설선을 통과하는 개별 카드데이터를 활용하였으며, 더 나아가 카드데이터의 특성을 고려한 열차 내 혼잡도 산정 알고리즘을 연구·개발하였다.

• Journal of Korean Medical classics
• /
• v.17 no.4
• /
• pp.95-105
• /
• 2004

• 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.

• Journal of The Geomorphological Association of Korea
• /
• v.24 no.2
• /
• pp.1-13
• /
• 2017

Massive coastal sand dunes are distributed in Ui-island, Shinan-gun. The sand dunes in Ui-island is worth studying, in terms of preserving natural environment without anthropogenic impacts. In this study, we surveyed geomorphological processes of the sand dune based upon measuring of geometric properties, grain size analysis, and OSL(Optically Stimulated Luminescence) age dating. The sediments of the dune consist mainly of well sorted medium sand with about 250$\mu$m. Based on spatial distribution of sand dunes, we found that they are formed by northwest monsoon during winter, and sands are supplied from Seongchon area in northern UI-island. According to OSL age dating, the sand dunes were deposited from $0.07{\pm}0.01ka$ to $0.17{\pm}0.04ka$. This result shows that the transformation of the dune due to the sand movement by wind was active during the last 100-200 years. The aerial photograph indicates that the dimension of the largest sand dune has decreased since 1945. Further research is needed to get more detailed information on geomorphic changes of sand dunes in UI-island.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2022.11a
• /
• pp.155-155
• /
• 2022

유조선 우이산호 부두시설 접촉사고는 광양항 원유 2부두에 접근 중 과도한 속력 등 도선사의 부적절한 도선으로 좌회두를 적절하게 통제하지 못해 발생한 사고이다. 광양항 원유 2부두에 접안하고자 하는 VLCC는 부두 법선을 감안하여 약 10도 이내의 경사각으로 서서히 속력을 감속하면서 부두 전면 해상으로 접근하여 부두로부터 선폭의 약 2~3배 거리에 정선시킨 다음 예선의 도움을 받아 접안 예정 선박을 횡방향으로 5~10 cm/s 속도로 평행 이동시켜 부두에 계류시키는 것이 통상적인 접안 방법이다. 하지만, 우이산호의 부두 접근 시 속력을 살펴보면, 부두 1마일 전에서 8.4노트, 부두 0.5마일 전에서 7.1노트, 그리고 부두 0.2마일 전에서 5.2노트로 정상적인 타 선박의 속력보다 2~3배 빠른 속력으로 부두에 접근하면서 예선을 사용하였음에도 속력제어에 실패하여 부두와 접촉한 사고이다.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.23 no.2
• /
• pp.187-193
• /
• 2017

This study evaluated tidal stream energy resources according to tidal flow properties around Uido off the west coast of, Jeollanam-do, South Korea. A feasibility study was first carried out through the collection of bathymetry data and tidal phase information. For this simulation, a depth-averaged 2D ADCIRC (Advanced Circulation) model for real sea situations was applied to a Finite Element Method (FEM) approach for tides given the variation of tidal current speed. Hydrodynamics were simulated with 4 major tidal constituents (M2, S2, K1, and O1) after setting up 4 observation points. From the real depth-averaged model simulation results, it was found that the spring tide Higher High Water (HHW) and tidal current speed values at the 4 observation points were about 2.2 m and 1.33 m/s, respectively. The ADCIRC model results were analyzed with reference to the Korea Hydrographic and Oceanographic Agency's (KHOA) observed data for verification. Furthermore, using topographical characteristics via the Tidal Flux Method (TFM), tidal energy density distribution was calculated, indicating a maximum tidal energy density of about $1.75kW/m^2$ for the 5 assessment areas around Uido. The tidal energy density was evaluated with consideration given to topographical characteristics as well as tidal elevation and tidal current speed to determine an optimum tidal farm candidate.

• Korean Journal of Environment and Ecology
• /
• v.20 no.1
• /
• pp.41-51
• /
• 2006

We investigated the flora of Ui Island sand dunes, consisting of 142 taxa; 52 families, 108 genera, 124 species, 15 varieties, and 3 forms. The total plants of floral region that were identified were 16 taxa; Elymus mollis, Salsola collina, and Farfugium japonicum in Class III; Ischaemum anthephephoroides, Carex kobomugi, Glehnia littoralis, Messerschmidia sibirica, Machilus thunbergii, Elaeagnus macrophylla, and Aster spathulifolius in Class I . Naturalized plants were 11 taxa; 7 families, 10 genera and the naturalization degree was 7.8%. On the Donmok seaside area, the coverage rate was about $20%{\sim}25%$ in 2002, but this time it had increased to more than three times or $65%{\sim}75%$. Also, on the Sungchon seaside area, the coverage rate was about $15%{\sim}20%$ in 2002, but this time it was $70%{\sim}75%$ as a result of the rapid increase of Zoysia macrostachya and Carex kobomugi. Pungseong sand dune area showed a monotonous state in variety and number, because of the strong wind and repetition of sand income and outcome.

• Journal of the Korean Society for Railway
• /
• v.16 no.2
• /
• pp.144-150
• /
• 2013

This paper presents an analysis of door design for the Ui LRT based on experiments to predict doorway flow-time and their analyses results. A similar railway vehicle (from Gimhae LRT) and operational conditions are utilized to assess the doorway flow-time through repetitive experiments. Design of the experiments consists of four scenarios, and the experiments are repeated 39 times in total. We use the results of the experiments to verify the design of doors of Ui LRT (e.g. the required number of doors and their width). Various statistical analyses are carried out for the flow-time with respect to the number of boarding/alighting passengers. We make three category levels of boarding/alighting passengers, and analyze the mean and variance for each category, and then carry out One-Way ANOVA to analyze how the number of boarding/alighting and onboard passengers impact flow-time. The results of this paper can be used for making decisions about doors of the LRT vehicle.

• Korean Journal of Environmental Biology
• /
• v.25 no.1
• /
• pp.56-65
• /
• 2007

The aim of this study is to provide a fundamental data which can be applied to management conservation, and restoration of coastal sand dune vegetation by determining the classification and distribution of community, and ecological characteristics of the habitat. This research was performed by the Braun-Blanquet's method. The coastal sand dune vegetation of Uido (I.) was composed with 9 communities as follows : Vitex rotundifolia community, Zoysia macrostachya community, Carex kobomugi community, Iachaemum anthephoroides community, Imperata cylindrica var. koenigii community, Carex pumila community, Calystegia soldanella community Messerschmidia sibirica community and Pinus thunbergii community, the evergreen needle-leaved forest. The constancy degree showed high in Calystegia soldanella (77%), Vitex rotundifolia (74%), Carex kobomugi (66%), Zoysia macrostachya (50%) and Imperata cylindrica var. koenigii (47%). However the highest constancy degree Calystegia soldanella has, it turned out to have low net contribution degree (NCD) in each community. In terms of the distribution and growth feature of the composition species in the coastal sand dune, Vitex rotundifolia, Carex kobomuri and Zoysia macrostachya were widely distributed from unstable sand dune to stable one but Iachaemum anthephoroides and Imperata cylindrica var. koenigii were mainly found at the stable sand dune. Carex kobomugi was especially dominant at the unstable sand dune where the sand continued to be deposited. On the other hand, Carer pumila and Messerschmidia sibirica showed regional distributions around fresh water.

• Korean Journal of Ichthyology
• /
• v.12 no.4
• /
• pp.259-263
• /
• 2000

The investigation of the fishes was conducted based on the specimens from the Wooi-Islands, southern west coast of Korea in August, 1998. The fishes were composed of 25 species and 22 genera belonging 15 families. Among them, the gobiid fishes composed of 6 species and the combtooth blennies of 3 species. The gobiid fishes, Chasmichthys dolichognathus, Tridentiger trigonocephalus and Synechogobius hasta were most commonly found in the intertidal area of these islands. One specimen collected from tidepool at tentatively identified as Abudefduf bengalensis of the family Pomacentridae for the first time from Korea. This species was characterized by having seven black bars on the trunk of body. A new Korean name "Huk-jul-dom" is proposed for this species.