• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.6
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• pp.12-18
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• 2004

This study is to make plans for perpendicular greening with artificial ground of planter type to improve urban environment. The experiments of this study are performed to find out the suitable soil and irrigation method for artificial ground of planter greening. Thereupon, organic or inorganic soil improvement material is mixed with soil of each planter as experiment, In result, the plants in soil mixed organic soil improvement material thrive rather than that in soil mixed inorganic material, It is to be desired that the planter equip with the irrigation system, be wider than planter and be planted shrubs for positive plant growth. As for irrigation system, drip irrigation is effective on plant growth southern exposure but Ebb and Flow is effective eastern exposure. Therefore, irrigation system should consist of two types above plus keeping water on the bottom of planter to save water and store rainwater.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.607-623
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• 1995

A numerical model of hydraulic resistance by hanging aquaculture facilities is developed and applied to a model basin and a field. A drag stress term formulated by the quadratic law of drag force is introduced Tn the equations of motion for a two-dimensional depth-averaged flow. In the model basin, numerical experiments ave tarried out for the various shape of obstructions, string density and layout of facilities etc.. The flow pattern around the facilities is affected sensitively by the density of string and the layout of facilities. On the other hand, the velocity decay due to the hanging oyster aquaculture facilities is observed in Kamak bay, where the maximum velcocity decay rate is $25\%$ in spring tide. The model is also applied to the field, Kamak bay. The velocity decay rate in the model is comparable with the field measurement data. The velocity decreases around the down-stream area of the facilities, .hut it increases in the other region. The water elevation decreases during the flood and it increases during the ebb.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.28 no.2
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• pp.117-131
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• 1992

A studies on the pattern of sea water circulation was carried out by using drogue experiments, tidal current measurement and hydrographic data in Kamak Bay which has two channels. At the flood, the water inflowed from the northern narrow channel flows mostly to the southward then the westward because Daekyung-island located at the flow path, at the same time the water from the southern channel of bay directed strongly to the north with a spine centered at around Gunnaeri. And these waters converged at the area between eng-Island and Deakyung-Island in the bigining of the flow, and placed at less southern part than the area at the late. The water of the north west inner bay having concave bottom topography inflows to Najin inlet with a spin of anti-clockwise. At the ebb, those waters in the bay turn back to two channels respectively, but most of waters directed to the southern channel of the bay. The directions of residual current of two channels are the southward mainly, and the current of inner area are influenced by the prevailing wind. The north-west inner bay which has the weak tidal current less than 10 cm/sec shows a similar upwelling by off-shore wind in winter, and the stratification in summer, respectively.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1144_1145
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• 2009

Tidal power station is using the difference of the ebb and flow and the single action tidal power is dependent on tide amplitude and basin volume. Therefore the inflow of basin in rainy season has also effect on the daily power. Also if operating units are changed then starting head too changed. Therefore the number of units are very important for the optimization model. According to our study the primary point when we make a determination of optimization is starting head and governorl control mode. On this study optimization model for tidal power station is considered all of this conditions.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.251-252
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• 2008

Si-Hwa tidal power station is using difference of the ebb and flow. The active power is dependent on up and down sea water level but if it is drastically changed because of a typhoon or waves the generator terminal voltage and active power is changed that is a chief cause of power station unstability. Therefore this paper arrange a present state of power or frequency fluctuation and generator terminal phase difference in case of occurrence a drastic change of sea water level.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.289-301
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• 2012

Tidal artificial lake capable of inflow and outflow of seawater is planned for waterfront and eco-friendly space at Songdo, Incheon, Korea. This study for hydrodynamic behaviors of tidal artificial lake was carried out and predicted about water level and velocity within the lake corresponding to width of channel or waterway using by 1 dimensional numerical model(CEA) and 2 dimensional numerical model(FLOW2DH). As a result, the proper width, 100.0m of the channel between the lake and the open sea was calculated reasonable conclusions such as tidal phase lag and maximum velocity from CEA. Also, water level and velocity of each point within the lake was predicted and compared to the measured data from FLOW2DH. FLOW2DH was added to the gate control case for maintenance and administration purpose of the lake and obtained the results that the velocity was decreased by approximately 20% at flood and 50% at ebb than the case without gate control.

• Journal of Environmental Science International
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• v.15 no.1
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• pp.45-58
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• 2006

In order to grasp physical characteristics of Ganajin Bay receiving the effluents from land, a comprehensive field surve)'has been conducted at the north of Wando and Gogeumdo in 2002. Water temperature was most high in September while most low in December. A high temperature in September was inferred to have caused by the dispersion of warm fresh water with favor of a dominant wind in autumn. However, salinity and sigma-t in situ was most low in September while most high in December. A low salinity (or density) in September turned out to reflect the influence of a dense rainfall in summer. Water temperature, salinity and density at the surface layer were lower than those at the bottom layer, except for December. Their horizontal profiles suggested the influence of effluents such as Tamjin River. Particularly, time series of water temperature acquired near the sluice and at the north channel of Wando tended to rise at the flood flow but fall at the ebb flow in accordance with the tide. The form ratio of the tide in the study area was $0.31\~0.32$ and the amplitude of the tide appeared to increase towards the west. Northeastward or southwestward flows prevailed in this area but the residual flows were all northeastward with a magnitude of $3\~4cm/s$.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.187-194
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• 2011

The objective of this study was to determine the effects of light intensity and electrical conductivity (EC) of nutrient solution on the growth and nutrient uptake of potted kalanchoe plants (Kalanchoe blossfeldiana 'Marlene') with growth stage in ebb and flow subirrigation systems. The plants were grown at four ECs of 0.5, 1.0, 1.5, and 2.0 $dS{\cdot}m^{-1}$ for seedling stage and four ECs of 1.0, 1.5, 2.0, and 3.0 $dS{\cdot}m^{-1}$ for short day stage under three daily photosynthetic photon flux (PPF) of 6.5, 10.3, 18.2 $mol{\cdot}m^{-2}{\cdot}d^{-1}$. At seedling stage, plant height was the longest under the lowest light intensity, and particularly dry weights and leaf areas were the highest at PPF 10.3 $mol{\cdot}m^{-2}{\cdot}d^{-1}$. Dry weights and leaf areas were the highest at EC 1.5 $dS{\cdot}m^{-1}$ regardless of light intensity. At short day exposure, plant height was the longest under the lowest light intensity. Dry weights, leaf areas, and number of pedicels of the plants significantly increased as light intensity increased. Under all light intensity conditions, dry weights, leaf areas, and number of pedicles increased until EC becomes to 1.0 - 2.0 $dS{\cdot}m^{-1}$. And after reached the highest at EC 2.0 $dS{\cdot}m^{-1}$, they decreased at EC 3.0 $dS{\cdot}m^{-1}$. By comparing the ion uptakes at EC 1.5 $dS{\cdot}m^{-1}$ of seedling stage and EC 2.0 $dS{\cdot}m^{-1}$ of short day stage in which the plants grew better, we confirmed that ion balance of nutrient solution among $NO_3{^-}$-N, $H_2PO_4{^-}$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were significantly changed at short day stage compared to seedling stage. For better growth of the plants, both ion balance and EC of nutrient solution should be considered under different light intensities at short day stage while control of EC is enough at seedling stage.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.81-88
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• 2011

Effect of concentrations of different plant growth retardants (PGRs) supplied to a recirculated nutrient solution in an ebb and flow system on the growth and development of potted Spathiphyllum 'Top-Pin' and 'Mini' was examined. Plants were planted in 10 cm diameter plastic pots filled with a mixture of peat moss and perlite (1 : 1, v/v) on 30 June 2005 and grown until 23 Sep. 2005. In a closed ebb and flow system, 50, 200, 350, $500mg{\cdot}L^{-1}$ daminozide (B-9), 10, 40, 70, $100mg{\cdot}L^{-1}$ paclobutrazol (Boundy), 5, 15, 25, $35mg{\cdot}L^{-1}$ ethephon (Florel), and 1, 4, 7, $10mg{\cdot}L^{-1}$ uniconazole (Sumagic) were supplemented to a nutrient solution at the initiation of experiment. On every irrigation, the nutrient solution containing PGRs was supplied at a 2 cm depth and kept for 15-20 minutes. The surplus nutrient solution was drained back into the tank for next irrigations. Paclobutrazol gave the most pronounced effect in inhibition of stretchiness. The greatest reduction of leaf length, fresh and dry weights of shoot, and elevated chlorophyll content were recorded in Spathiphyllum, with increasing paclobutrazol concentration. Daminozide concentration greater than $200mg{\cdot}L^{-1}$ resulted in minor stunting. The lowest concentration ($1mg{\cdot}L^{-1}$) of uniconazole showed greater leaf length, leaf width, and leaf petiole length than the control ($0mg{\cdot}L^{-1}$). Uniconazole concentration greater than $1mg{\cdot}L^{-1}$ resulted in similar plant growth as the plant in the control ($0mg{\cdot}L^{-1}$). High concentration ($35mg{\cdot}L^{-1}$) of ethephon resulted in the shortest leaf length, and the greatest chlorophyll content. Inhibition of stretchiness was observed even in the lowest concentration treatments. Among the PGRs, paclobutrazol was most effective in suppressing plant stretchiness. In both cultivars, ethephon and paclobutrazol, but not daminozide and uniconazole, significantly inhibited stretchiness. The results suggested that plant growth retardants (ethephon or paclobutrazol) selected in this study may be used as the most effective agents for inhibition of stretchiness in Spathiphyllum.

• Journal of Bio-Environment Control
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• v.13 no.2
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• pp.112-119
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• 2004

Objective of this research was to evaluate the effects of nutrient solution strength and Arbuscular Mycorrhizal Fungi (AMF, Glomus sp.) on growth and flowering of potted miniature rose (Rosa hybrids L. cv 'Scarlet'). To achieve this, plants cultured with six different strength of Japanese Horticultural Experiment Station solution (0.125, 0.25, 0.5, 1.0, 2.0, and $4.0\;{\times}\;{full}$ strength) and inoculated with AMP at cutting and transplanting. Leachate EC increased as solution strength were elevated. The leachate EC were not different between non-inoculated plants and AMF treatment at cutting, but significantly decreased when plants were inoculated with AMF at transplanting. The elevated strength of nutrient solution resulted in decrease of leachate pH. When plants were inoculated AMF at transplanting, leachate pH was lower than those of non-inoculated plants and inoculated with AMF at cutting. At harvesting (93 days after transplanting), plant height, leaf width, number of branches and shoot fresh and dry weight of rose 'Scarlet' increased with elevated nutrient solution strength. AMF treatment at transplanting of potted rose 'Scarlet' showed the best results in growth such as chlorophyll content, number of flowers, and shortening the days required to flower. The content of N, P, K, and Mn in leaf tissue of potted rose increased by elevated nutrient solution strength and AMF treatment, while the tissue Na contents decreased by an AMF treatment.