• Title/Summary/Keyword: proximity function

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A Study on the Estimation of Service Level for National Fishing Harbour Breakwater Lighthouse Based on the Traffic Volume (통항량 기반의 국가어항 방파제등대 서비스수준 추정 연구)

  • Moon, Beom-Sik;Song, Chae-uk;Kang, Jeong-Gu;Kim, Tae-Goun
    • Journal of Navigation and Port Research
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    • v.45 no.6
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    • pp.306-313
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    • 2021
  • National fishing harbour is as a refuge for fishing boats and a breakwater lighthouse is installed as a functional facility in consideration of harbour identification and the safety of passing vessels. In this study, the service level of breakwater lighthouse (234 units) was estimated based on the traffic volume of 105 national fishing harbour. For this purpose, the evaluation items were determined, the fishing harbour standard index was calculated (Fs=1), the proximity of fishing harbour was identified and the function (service level) of the breakwater lighthouse was estimated in the following order. However, national fishing harbour differed in size, traffic volume and fishing vessel capacity. Therefore, 105 national fishing harbour were divided into three groups through cluster analysis. The cluster analysis was based on the service level factors of the breakwater lighthouse, such as the number of weeding fishing vessels, tonnage of fishing vessels, the number of incoming and outgoing vessels per year, and fishing vessel capacity. As a result of the estimation, the service level of the breakwater lighthouse (light tower height, visual height, visual range, interval) was 10.50m, 16.50m, 7.00mile, 5.5sec for group 1, and 10.67m, 16.16m, 8.33mile, and 6.0sec for group 2, The three groups are 11.53m, 16.75m, 6.75mile and 5.0sec. The results of this study can be used as useful basic data for improving the service level of traffic vessels when a breakwater lighthouse is built in a fishing harbour in the future.

Monitoring the Alternative Habitat of Kaloula Borealis and Analysis on Meteorological Factors in Pyeongtaek (평택지역의 맹꽁이 대체서식지 모니터링 및 기상요인 분석)

  • Min-Ho Choi;Yang-Seop Bae
    • Journal of Life Science
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    • v.34 no.4
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    • pp.264-270
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    • 2024
  • This study is conducted to analyze environmental factors that affect the ecology of boreal digging frog and use them as basic data for selecting (or creating) suitability of alternative habitats for survival and monitoring method from 2020 to 2022 after boreal digging frog were relocated to the alternative habitats in 2019. Analyzing the environment of the alternative habitats showed that the criteria suited the followings: distance from wetlands, grasslands and rivers was within 5 m, the low-rise grassland was 6,000 m2, soft soil was at a depth of ≥20 cm, and the area of permanent wetlands was 5,000 m2 wide. As a result of the correlation analysis between meteorological factors and population (n) and breeding, there was a significant correlation between rainfalls and breeding (p<0.01). During the monitoring, it was confirmed that the SVL (Snout-Vent Length) and BM (Body Mass) of the translocated population were maintained (p>0.05), and it was found that the proximity of the habitat and spawning pond, securing food space (grasslands), soil quality, and wetlands could function as an alternative habitat if conditions were met. As a result of analyzing the meteorological factors affecting the population of boreal digging frog, the SVL had a statistical impact on the minimum temperature, maximum temperature, relative humidity, and the rainfall (p<0.05). In the case of breeding, rainfall was found to be affected (p<0.01), and the population was statistically affected by the average temperature, minimum temperature, and relative humidity (p<0.05).