• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.4
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• pp.258-267
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• 2004

Coastal and harbor structures, which are constructed for the beach protection and coastal zone development, often cause the severe beach erosion problem resulted from changes of longshore sediment transport. In this study, we present a new methodology to estimate the longshore sediment transport rates using the measured data of beach profiles or shorelines. The methods is applied for the prediction of longshore sediment transport rates along Kailua beach, Hawaii and shorelines in the vicinity of Anmok Harbor, Korea.

• Journal of Environmental Science International
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• v.13 no.3
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• pp.263-277
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• 2004

The purpose of this study is to analyze the characteristics of riverbed variation due to the sediment protection weir located on the estuary of the main stream of Taehwa river using I-D finite difference model, HEC-6 model, and the followings are the results of estimating sediment transport rate, amount of scour or deposition, and accumulated amount of deposit according to before and after of the sediment protection weir removal with various flow rates in the channel. Ackers-White transport function produced the greatest sediment transport rate while Meyer-Peter showed the smallest sediment transport rate at the most down stream area of the watershed through the sediment transport rate analyses for various flow rates according to the existence or nonexistence of the sediment protection weir. Toffaleti's and Colby transport function were closest to the average value, and the difference among the results of the sediment transport functions showed up to 8～9 times. Duboy's transport function produced the greatest riverbed variation while Toffaleti's showed the smallest variation through the riverbed variation analyses according to the existence or nonexistence of the sediment protection weir. Yang's was closest to the average value, and the difference among the results of the riverbed variation analyses ranged from 1.4 times to 11 times. It is thought that a sediment transport function must be selected very carefully with respect to the criteria of sediment yield estimation because the analysis results of the sediment transport rate and riverbed variation according to flow rates showed significant differences among the sediment transport functions, and the differences of sediment transport rate and riverbed variation according to the various sediment transport functions decreased as the flow rate increased.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.12
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• pp.1796-1804
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• 2016

The high incidence of deaths during transport for slaughter is associated with poor welfare and represents a considerable loss to the poultry industry. In the period from 2009 to 2014, all shipments of broiler chickens to poultry processing plants were monitored in the Czech Republic and the numbers of chickens transported and those dying as a result of their transport were recorded and analysed. Overall transport-related mortality of broiler chickens transported for slaughter in the Czech Republic was 0.37%. It ranged from 0.31% to 0.72%, the increase approximately corresponding to the increasing transport distance. Statistically highly significant (p<0.001) differences were found when comparing transport-related mortality rates in individual seasons of the year. The greatest mortality (0.55%) was associated with transports carried out in winter months whereas the lowest death losses (0.30%) were found in chickens transported for slaughter in summer months. Our study revealed greater transport-related mortality rates in broiler chickens transported for slaughter in the Czech Republic than expected when considering earlier studies. The most pronounced increases were found in transports for shorter distances and in winter months. However, an increase was found at all transport distances monitored except for distances exceeding 300 km and all seasons except for summer. Furthermore, a general increasing tendency in chicken losses during the monitored period was found. The particularly alarming finding is that the mortality of broiler chickens being transported to processing plants has been showing a long-term increasing tendency over the last two decades. Further research should focus on the identification of specific factors leading to such high and growing mortality rates and developing practical guidelines to improve the welfare of the birds in transit accordingly.

• Journal of Photoscience
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• v.1 no.2
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• pp.95-105
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• 1994

Experiments were carried out to investigate whether P, deficiency in detached 25 mM mannose-feeding led to a decline of the photosynthetic electron transport rates through acidification of the thylakoid lumen. With increasing mannose-feeding time, the maximal CO2 exchange rates and the maximal quantum yields of photosynthesis decreased rapidly up to 6 h by 73% then with little decrease up to 12 h. The ATP/ADP ratio declined by 54% 6 h after the treatment and then recovered to the control level at 12 h. However, the NADPH/NADP~ ratio was not significantly altered by mannose treatment. Electron transport rates of thylakoid membranes isolated from 6 h treated leaves did not change, but they decreased by 30% in 12 h treated leaves. The quenching analysis of Chl fluorescence in mannose-treated leaves revealed that both the fraction of reduced plastoquinone and the degree of acidification of thylakoid lumen remained higher than those of the control. The reduction of PSI in mannose fed leaves was inhibited due to acidification of thylakoid lumen (high qE). The reduction of primary quinone acceptor of PSII was inhibited by mannose feeding. Mannose treatment decreased the efficiency of excitation energy capture by PSII. Fo quenching was induced when treated with mannose more than 6 h, and had a reverse linear correlation with (Fv)m/Fm ratio. These results suggest that Pi deficiency in Chinese cabbage leaves reduce photosynthetic electron transport rates by diminishing both PSII function and electron transfer from PSII to PSI through acidification ofthylakoid lumen, which in turn induce the modification of photosynthetic apparatus probably through protein (de)phosphorylation.

• Journal of the Korean Chemical Society
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• v.28 no.3
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• pp.170-175
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• 1984

The transport rates of $H^+$ ion by DBC and DCC as carrier molecules through organic liquid membranes were determined at 25$^{\circ}$C. The transport rates depend highly on the dielectric constants of membrane solvents and these results were discussed in terms of Born's potential energy barrier methods. The sizes of anions also affect the transport rates and these results were well explained theoreticlly by extended Born's equation.

• Journal of Korea Water Resources Association
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• v.37 no.12
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• pp.1033-1041
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• 2004

A 2-dimensional numerical sediment transport model using erosion rates in undisturbed conditions has been developed and applied to calculating the suspended sediment concentrations and bed level changes in the Lower Fox River The model reduces inaccuracy of sediment model by using the accurate erosion rates obtained in a flume (called Sedflume). The flume has been developed to measure erosion rates as a function of sediment depth and at the situation of high shear stresses such as flood event. Both mechanisms of suspended load and bedload transport are included in the model. The model results were verified for the description of sediment transport in a straight channel and the sediment transport during flood event in the Lower Fox River The results of Lower Fox River simulation showed good agreements with the observed SS concentrations. This model can be used to simulate sediment transport under the high shear conditions such as flood.

• Journal of the Korean Chemical Society
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• v.41 no.2
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• pp.77-81
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• 1997

The transport rates of transition metal cations were increased in order of Ni(II)$(NtnOenH_4)$and 1,12,15-triaza-3,4;9,10-dibenzo-5,8-dioxacyclo-heptadecane$(NdienOenH_4)$as carriers. The transport rates of transition metal cations was found to be of first order to the salt concentrations. It was also found that the dissociation process in the transport process is rate determining step. From the measurements of the transport rates at various temperatures, the partition free energies of hydration$({\Delta}G_p)$for the transition metal cations were calculated. The results showed that the order of transport rates of transition metal cations was found to be proportional to the magnitudes of negative value of the partition free energies of hydration$({\Delta}G_p)$.

• Journal of the Korean Institute of Navigation
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• v.13 no.1
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• pp.77-106
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• 1989

Two numerical models of the shoreline change and sediment transport rates, explicit and implicit, are simulated with shore structures such as breakwaters, a jetty, groins and a seawall. The applied study area is songdo Beach, Youngil bay, Korea since it has all the shore structures mentinoed above. The two models investigate the beach line changes and sedimen transport rates for the beach before design of three groins with and without an offshore breakwater. In order to estimate the shoreline changes after three groins were built, the beach response inside the three groin compartiments and the offshore barrier are also investigated. The simulation based on the initial shoreline conditions surveyed by the Hydrographic office, Koreai 1979 and 1984. The breaking wave characteristics are introduced into the models by calculation from the empirical equations and modification from the numerical and hydraulic model test results developed for waves behind an offshore breakwater. The numerical simulation describes well the tendencies of the sand transport and shoreline changes affected by wave diffraction behind a detached breakwater and by interruption of sand transport at three groins.

• Journal of the Korean Wood Science and Technology
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• v.20 no.2
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• pp.73-80
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• 1992

The effect of presteaming on native oak specimens(Quercus serrata) of 2.5cm thick were investigated by measuring specific gravities, internal moisture gradients, residual extractives, and transport rates of free and bound water. The specific gravities and internal moisture gradients of the presteamed samples did not much deviate from those of the controls, but after presteaming discrepancy in moisture content between specimens lessened. The amount of residual hot-water extractives of the presteamed samples were less than those of the controls by 25%. The transport rates of bound water were determined by measuring steady-state diffusion coefficients with a vapormeter cup. After presteaming the diffusion coefficients in radial direction increased by 35%, but decreased those in the tangential direction.

• Journal of Pharmaceutical Investigation
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• v.22 no.4
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• pp.289-300
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• 1992

The counter-transport phenomena in the hepatic transport of 1-anilino-8-naphthalene sulfonate (ANS) were kinetically investigated by analyzing the plasma disappearance-time profiles and the transport into the isolated hepatocytes. In vivo "counter transport phenomena" were simulated based on the perfusion model which incorporated the carrier-mediated transport and the saturable intracellular binding. The condition that the mobility of carrier-ligand complex is greater than that of free carrier is not essential for the occurrence of counter-transport phenomenon. To examine the inhibitory effects on the initial uptake of a ligand by the liver, it is necessary to judge whether the true counter-transport mechanism (trans-stimulation) is working or not. The initial plasma disappearance curves of ANS were then kinetically analyzed based on a two-compartment model, in which the ligand is eliminated only from the peripheral compartment (liver compartment). No effects on the initial plasma disappearance rates of ANS were observed after preloading of bromophenol blue (BPB) or rose bengal (RB) in the liver. Inhibitory effect of BPB or RB on the initial uptake (or efflux) rates of ANS by the isolated hepatocytes were not observed, suggesting that the true counter transport mechanism is not working. In conclusion, checking the preloading effects of transstimulation on the initial uptake of a ligand by the liver could be a useful criterion for carrier cycling and common use of the same carrier between two ligands. However, one cannot exclude those possibilities even if the preloading effects cannot be observed.