• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.479-483
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• 2004

A new calculation method of expected overtopping probability of rubble mound breakwater considering real tide occurrence has been proposed. A calculation method of expected overtopping probability of rubble mound breakwater was proposed by Kweon and Suh (2003). In their calculation, the fluctuation of tidal elevation was expressed by the sinusoidal change that yields the uniform distribution of occurrence frequency. However, the realistic distribution of tidal elevation should influence on the overtopping chance. In this study, the occurrence frequency of tidal elevation obtained from the real sea is included. The tidal elevation used in this study is collected from the east coastal part of Korean peninsular. Analyzing the annual data of the tidal fluctuation measured hourly during 355 days, the distribution of occurrence frequency is formulated utilizing by the normal distribution with one peak. Among the calculation procedures of annual maximum wave height, wave height-period joint distribution, wave run-up height and occurrence frequency of tide, only the annual maximum wave height is again chosen randomly from normal distribution to consider the uncertainty. The others are treated by utilizing the distribution function or relationship itself, It is found that the inclusion of the variability of tidal elevation has great influence on the computation of the expected overtopping probability of rubble mound breakwater. The bigger standard deviation of occurrence frequency is, the lower the overtopping probability of rubble mound breakwater is.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.2
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• pp.87-95
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• 2000

Spectral wave models are applied to the area of Kyung-gi bay with two different combinations. One combination assumes a constant tidal elevation over the whole region when applying the wave model to the area. In this case no tidal currents exist in any place. The other combination employs tide model as well as wave model so that tidal condition is defined at every computation time when wave modelling is carried out. Significant wave heights and wave directions are shown for these two cases. With these two different constraints of tidal variation, the results are checked and compared with each other. Both results are found significantly different from each other.

• Journal of Environmental Science International
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• v.23 no.4
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• pp.661-672
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• 2014

Due to tidal force, it is very difficult to estimate the hydraulic parameters of high permeable aquifer near coastal area in Jeju Island. Therefore, to eliminate the impact of tidal force from groundwater level and estimate the hydraulic properties, tidal response technique has been mainly studied. In this study we have extracted 38 tidal constituents from groundwater level and harmonic constants including frequency, amplitude, and phase of each constituent using T_TIDE subroutine which is used to estimate oceanic tidal constituents, and then we have estimated hydraulic diffusivity associated with amplitude attenuation factor(that is the ratio of groundwater level amplitude to sea level amplitude for each tidal constituent) and phase lag(that is phase difference between groundwater level and sea level for each constituent). Also using harmonic constants for each constituent, we made the sinusoidal wave and then we constructed the synthesized wave which linearly combined sinusoidal wave. Finally, we could get residuals(net groundwater level) which was excluded most of tidal influences by eliminating synthesized wave from raw groundwater level. As a result of comparing statistics for synthesized level and net groundwater level, we found that the statistics for net groundwater level was more insignificant than those of synthesized wave. Moreover, in case of coastal aquifer which the impact of tidal force is even more than those of other environmental factors such as rainfall and groundwater yield, it is possible to predict groundwater level using synthesized wave and regression analysis of residuals.

• 한국해양학회지
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• v.14 no.2
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• pp.71-77
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• 1979

Tidal waves and the fluctuation of current are studied by use of observed data on tidal level, flow velocity and river discharge in the estuarine region of the Nakdong River. Observed data on the tidal level at five stations are used to obtain the fluctuation of amplitude and phase of tides, and the change of the wave speed versus distance from the river mouth. Comnining these tidal data with the vertical distribution of horizontal velocity data, some characteristics of the periodic tidal flow are deduced: (1)Diminishing rates of the tidal amplitude ratio η / η$\_$0/ at high tide were 0.058η$\_$0H/ /Km at neap tides. The constant of phase change, K, was 0.035rad/km. (2)While proceeding landward, the shape of the tidal wave changes from symmetrical to asymmetrical. The traveling speed of the tidal wave crest was estimated to be 3.6∼5.2m/sec, while that of the tidal wave trough was 2.4∼ 3.5m/sec. (3)The flowing speed of the water varies periodically in accordance with the tidal period. The maximum speed of landward flow appeared approximately at two hours before the high tide, while that of seaward flow at two hours before the low tide. (4)The upstream boundary is deduced approximately to be 50km at spring tide and 44km at neap tide from the tidal velocity decreasing. the tidal influence area is estimated approximately to be 65km from the tidal amplitude damping.

• Coupled systems mechanics
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• v.7 no.5
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• pp.611-626
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• 2018

We theoretically consider a possible influence of periodic oceanic tides on non-periodic changes in the dynamics of the Earth and Moon over a long time scale. A particular emphasis will be placed on the contribution from rotating tidal waves, which rotate along the inner edge of an oceanic basin surrounded by topographic boundary. We formulate the angular momentum and the mechanical energy of the rotating tidal wave in terms of celestial parameters with regard to the Earth and Moon. The obtained formula are used to discuss how the energy dissipation in the rotating tidal wave should be relevant to the secular variation in the Earth's spin rotation and the Earth-Moon distance. We also discuss the applicability of the formula to general oceanic binary planets subject to tidal coupling.

• Journal of Radiation Industry
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• v.4 no.4
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• pp.391-395
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• 2010

The characteristics for pollutant transport in tidal influenced area was investigated using tidal wave hydraulic scale model. Hydraulic scale model was composed of the tidal generator, attenuation area and channel. Also, wave height, current meter and conductivity meter were used with the measured instruments in hydraulic scale model. NaCl with a tracer was used to evaluate the advection phenomena under the different velocity profiles. The arrival time of the maximum concentration in the condition of the relatively fast velocity was measured about 30 seconds faster than ones in the conditions of low velocity. The measured concentrations of the tracer were shown in the detection points of the flow direction consecutively.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.5
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• pp.465-472
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• 2019

This paper describes the resource assessment of theoretical potential of ocean energy including tidal current energy, tidal range energy, wave energy and ocean thermal energy in Korea to provide reliable basis for feasible development plan of ocean energy. Because of different characteristics of each ocean energy resources, the resource assessment methods were established considering characteristics of each ocean energy resources. The coastal region of Korea has been divided into 10 regions. The results show that tidal current energy is abundant in Incheon-Gyunggi and Jeollanam-do and tidal range energy is abundant in Incheon-Gyunggi. And wave energy is abundant in Jeollanam-do, Jeju and Gyeongsangbuk-do and there is ocean thermal energy in Gangwon-do and Gyeongsangbuk-do.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.166.2-166.2
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• 2011

Incheon Bay of Korea is one of the most famous regions for high tidal range. Ministry of Land, Transport and Maritime Affairs(MLTM) has implemented preliminary investigation for tidal power energy development in this area since 2006. Through field observations, various kinds of marine data consisting of depth and geography, marine weather, tidal currents, wave, seawater characteristics, geology, marine ecosystem and marine environment were gathered. To use these data efficiently for the determining of feasibility of developing and appropriateness of project scale, spatial data management and application system is essential. Therefore, in this study, the concept, methodology and procedure of spatial data modeling are defined for tidal energy development. Spatial data modeling consists of essential model relating to tidal energy directly and optional model including environmental factors. Essential model is composed with fundamental elements like as depth, geography, and several numerical modeling results(tide, tidal current, wave).

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.4
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• pp.3-11
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• 2001

To know the seawater infiltration into tidal flat sediment in coastal area is very important, because it is significantly correlated with the infiltration and transportation of pollutants in soil, the supply of dissolved oxygen, nutrients and organic matter to benthic organisms for survival of benthic organisms and the seawater purification. So, we set up purpose to clarify the infiltration behavior of seawater by wave action in tidal flat, to clear the effects of slope of tidal flat and breaking wave height on seawater infiltration and to quantify the infiltration volume of seawater. For purpose, the seawater infiltration was studied with visualization method by using coloring tracer and transparent glass beads replaced as natural sediment in model tidal flat. Specific conclusions derived from this study are as follows. The semi-circular type infiltration of seawater by wave action into saturated sediment was a new infiltration behavior that was not considered in previous studies. The infiltration rate of seawater was increased with increasing of breaking wave height and slope of tidal flat. However, the effects of the slope was bigger than that of breaking wave height on seawater infiltration into tidal flat sediments. It was possible to calculate the infiltration volume of seawater by wave action in natural tidal flat sediment and in fields. Therefore, we can point out that wave action play an important role in the supply of dissolved oxygen, nutrients and organic matter to benthic organisms, transportation or diffusion of pollutants and seawater purification. So, we hope to be studied the supply of food to benthic organism, pollutant transport and seawater purification on the base of these results.

• Journal of Korea Water Resources Association
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• v.54 no.6
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• pp.433-442
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• 2021

In order to examine the characteristics of tidal wave from the estuary to upsteam of tidal river, tidal asymmetry was identified based on analysis of the harmonic constants of M2 and M4 tidal constituents in the domestic western coastal regions. As shallow water tide is greatly developed in the estuary, flood dominance in Han River and Keum River, and ebb dominance in Youngsan River are developed. These tidal asymmetries can be reconfirmed by analyzing the tidal current data. Unlike having reciprocating tidal current patterns in Keum and Youngsan estuaries, rotaing tidal current pattern is shown in the Han River estuary due to the complex topography and waterways around Ganghwa Island area. However, when residual current is removed, flood dominance is shown in consistency with the tide data. The tidal asymmetry in the estuary tends to intensify with the growth in shallow water tide as the tidal wave propagates to upstream of tidal river. Energy dissipation, in shallow Han River and Keum River classified as SD estuaries, is very large regarding bottom friction characteristics. On the other hand, the deep Youngsan River, classified as a WD estuary, shows less energy dissipation.