• Title/Summary/Keyword: tranquility

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Recent Topics on Harbour Tranquility on Ship Motions

  • Shiraishil, Satoru
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2003.08a
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    • pp.1-9
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    • 2003
  • This paper discusses on recent topics on harbour tranquility base on ship motions. Harbour tranquility is mainly discussed only wave height inside a harbour at the first research period. In these twenty years, researches to improve harbour tranquility have been focused on ship motions to reduce mooring troubles facing to open seas. (omitted)

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Analysis of the Physical Characteristics and Tranquility of the Valley in Gangwon Province (강원지역 계곡의 물리적 특성 및 고요함 분석)

  • Kim, Kyoung-Nam;Han, Gab-Soo
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.152-160
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    • 2014
  • The purpose of this study is to investigate and analyze the physical characteristics and tranquility of the valleys located in Gangwon region. For this study we analyzed the field survey data 135 valleys using GIS. The elements for measurement of tranquility were divided into visual elements including terrain, objects, forest, water and auditory elements including noise. These elements were divided further into positive and negative factors. The weight of each element and item was calculated by applying the AHP method. The results of this study are as follows. The length of the valley ranged from 126 m to 17 km, and the elevation ranged from 40 m to 1,800 m. Type of mixed forest was common in the valleys. The depth of the water was over 20 cm in 83% of the total area and most of the water was in good condition in visual quality. Regarding the positive factors of tranquility, the weighted scores of the objects, waterfall sounds and visual transparence of the water were of relatively high value. Relatively high values were also shown in closed and curved topography in the landform, forest type and natural forests. In the negative factors, the weights of the objects and forest elements had high values. Within the facility groups, facility of the river produced a considerable negative. After applying the index of tranquility, the natural physical attributes affected the tranquility value, more than the manmade structures to a much greater degree.

Analysis of Harbor Tranquility due to Port Expansion

  • Moon, SeungHyo;Lee, JoongWoo;Kwon, SeongMin;Song, HyunWoo
    • Journal of Navigation and Port Research
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    • v.43 no.5
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    • pp.320-327
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    • 2019
  • This study examined the port expansion plan for the fishery port at the east coast of Korea, in accordance with permission conditions for coastal ports such as a limit on the cargo volume and passenger demand for the coastal tourism belt formation. The site was chosen as a municipal coastal port attracting the new ocean industry and building waterfront zone as a hub of new marine tourism. Two different numerical models (Swan and Bouss 2D) were used. Before applying to the target sea area, some numerical tests were conducted for the variation according to Bouss-2D's strong/weak and nonlinear technique compared to the irregular diffraction of semi-infinite breakwater with a theoretical solution. As a result, there was a difference in strong nonlinearity with breaking waves and it was necessary to experiment with a strong nonlinear analysis technique for the actual site. Two numerical models were applied to the fishery port site and the tranquility of some alternatives were analyzed. The numerical results show the most suitable plan was ALT-1, with satisfied harbor tranquility and reasonable economic sense. The extension of the east breakwater and enlarged turning basin of the F-Land plan have brought generally more stable harbor tranquility than the ALT-1. The result can be used as a reference for the port expansion plan in the future.

A Fundamental Study on the Improvement of Harbour Tranquility and Water Quality of Fishing Port (어항의 정온도 향상과 수질개선을 위한 기초적 연구)

  • Ryu, Cheong-Ro;Kim, Jong-Hwa;Park, Jong-Hwa
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.4
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    • pp.341-352
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    • 1990
  • The purpose of this research is to develop the design/control method that can be used for the improvement of harbour tranquility and water quality of fishing ports. For this end, firstly, the hydraulic environmental characteristics of fishing ports in the coastal waters of the Korean Peninsula are analysed and discussed combined with disasters of facilities and vessels in the ports. Secondly the problems of water quality control is pointed out considered with the improvement measures of harbour tranquility such as the methods of lengthen of main breakwaters and construction of wave absorbing structures. Finally, the control characteristics of composite functions of water quality and tranquility of fishing port are discussed and the improved control method si proposed using the experimental results for the various measures. The proposed measure is proved to be a applicable method to improve these two main functions on the design of fishing port.

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The Construction Plan of Breakwater by the Numerical Simulation (수치시뮬레이션에 의한 방파제의 시공계획)

  • Kim, Kyu-Han;Yoon, Seong-Jin;Kim, Young-Bok
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2006.11a
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    • pp.449-452
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    • 2006
  • The main external force of the harbor in east coast is wave. So, wave is the important cause of wave induced current and sediment transport due to wave in planning harbor structures. Therefore, it must be considered not only to secure the harbor tranquility but also the sediment transport due to wave induced current in planning the harbor. In this study, we studied on the influences of construction procedure on harbor tranquility and siltation using annual coastal line data and bathymetry data near breakwater. And it suggests that the construction procedure for the harbor tranquility and the best way for the decrease of harbor siltation.

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Research on improvement measures of Harbor tranquility in Geumjin Fishing Port Excited by Incident Short Random Waves (단주기 불규칙파에 의한 금진항 정온도 개선대책 연구)

  • Chang, Sung-Yeol;Moon, Yong-Ho;Park, Won-Kyung
    • Journal of Coastal Disaster Prevention
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    • v.4 no.1
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    • pp.1-6
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    • 2017
  • Most of the short period waves are blocked by the breakwaters when the short period irregular waves propagate into the ports. However, nonlinear irregular wave numerical experiments show that the long waves generated by the nonlinear interaction is predominant in the port. Seiches phenomenon in Geumjin Fishing Port is very similar to 60 and 300 second harbor oscillations. By arranging the inner breakwater of the proper length in the inside of the port, it is possible to effectively reduce seiches, as well as the short-period wave, and significantly improve the harbor tranquility. In the case of rectangular basin type such as the Geumjin Fishing Port, the multi-directional irregular wave numerical model should be used for the investigation and countermeasures for the harbor tranquility.

Field investigations on port non-tranquility caused by infra-gravity water waves

  • Najafi-Jilani, A.;Rahimi-Maleki, D.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.2 no.1
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    • pp.34-38
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    • 2010
  • Field investigations have been carried out in two 60-day stages on the surf beat low frequency waves in Anzali port, one of the main commercial ports in Iran, located in southwest coast of the Caspian Sea. The characteristics of significant water waves were measured at three metering stations in the sea, one at the entrance of the port and three in the basin. The measured data were inspected to investigate the surf beat negative effects on the tranquility of the port. Using field measurements and complementary numerical modeling, the response of the basin to the infra-gravity long waves was inspected for a range of wave frequencies. It was concluded that the water surface fluctuations in the port is strongly related to the incident wave period. The long waves with periods of about 45s were recognized as the worst cases for water surfaceperturbation in the port. For wave periods higher than the mentioned range, the order of fluctuation was generally low.

Review of the Improvement of the Estimation Method of Harbor Tranquility (항만정온도 추정방법 개선방안 검토)

  • Jeong, Weon Mu;Ryu, Kyong-Ho
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.26 no.6
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    • pp.397-404
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    • 2014
  • In Korea, harbor tranquility is generally estimated by using both methods of investigating harbor calmness under abnormal wave condition and evaluating the harbor serviceability. The efficiency of the former method is questionable as the tranquility of a harbor is judged by a wave height criterion that is arbitrarily determined without rational basis. In case of the latter method, the utilization rate of a harbor is estimated by using the exceedance probability of wave height or the distribution of wave heights and periods that is obtained from longterm measured or hindcasted wave data. Use of long-term data is desirable in order to guarantee the accuracy of the exceedance probability. Meanwhile, the criterion for determining maximum allowable wave height for cargo handling works is too simple and has limitations for being used in an actual field condition. Problems of existing method for estimating harbor tranquility were verified by the wave observation data in Busan New Port. And the importance of the field observation data was emphasized. It is necessary to perform long-term wave monitoring inside and outside of major ports in Korea in order to establish more advanced standard for evaluating harbor tranquility based on such observed wave data.

Evaluation of Harbour Tranquility Improvement in Pohang New Port by Detached Breakwater (포항신항 도제 축조에 따른 정온도 개선 효과분석)

  • Ryu, Kyong Ho;Jeong, Weon Mu;Kwon, Jinseong;Chang, Yeon S.;Baek, Won-Dae;Kim, Won Goung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.32 no.4
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    • pp.230-241
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    • 2020
  • Since the construction of Pohang New Port, the problems of the low harbor tranquility caused by decreasing port operation rate has been continuously reported. In order to improve the harbor tranquility, a detached breakwater (DB) has been constructed outside the outer breakwater of Pohang New Port in 2018~2020. In this study, the effectiveness of the DB was proved by comparing the reduction rates of wave heights that were observed before and after the construction of the DB. First, the observed data were compared with the numerical model results available from a previous study, and the model data showed reasonable agreement with measured data at 3 out of 4 locations inside the port. The discrepancy in one of the locations was because the model could not accurately calculated the effect of wave interference in the inner corner of the port. The observation data showed excellent results that the number of waves that exceeded 0.3 m, the critical value to reach desired harbor tranquility, was significantly reduced after the construction of the DB. In addition, the reduction rate, the ratio of wave heights between outside and inside of the port, was decreased after the DB construction, which proved that properly designed coastal structures such as DB in this study could be effective in improving the port tranquility. The results of this study can be usefully applied for solving problems in similar cases.

Analysis of Harbor Tranquility in Pohang New Harbor Using a Hyperbolic Model with Multi-Directional Incoming Waves (다방향 입사파의 쌍곡형 수치모형에 의한 포항신항내 항내정온도 분석)

  • 정원무;이창훈;채장원
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.9 no.2
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    • pp.97-104
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    • 1997
  • A hyperbolic numerical model with multi-directional waves has been used to investigate harbor tranquility in Pohang New Harbor. Comparing numerical results with field data measured at two stations in the harbor, it was found that use of input condition of multi-directional waves is superior to the use of uni-directional waves. Calculations with unidirectional wave input give errors of about 12% at St. P2 and 26% at St. P3, while calculations with multi-directional wave input give errors of 4 % at St. P2 and. 14% at St. P3. Using the input condition of multi-directional waves, we investigate the tranquility of Pohang New Harbor with two layouts : the condition in 1994 when the downtime at the 7th pier was often reported and the condition in 1996 when the 4th disposal site was constructed. The numerical results show that the problem of downtime at the 7th pier cannot be solved by the construction of the 4th disposal site.

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