• 한국해안해양공학회지
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• 제16권4
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• pp.258-267
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• 2004

해안 방재 또는 연안 개발 목적으로 축조되는 해안 및 항만 구조물은 건설된 후 건설 전의 연안 토사 이동의 양상을 변화시켜 해안선 침식은 물론 해안 환경까지 영향을 미친다. 본 연구에서는 건설 후의 해안선 변화 예측을 위하여 필수적인 해안선 또는 해안 단면 자료를 이용하여 연안 표사 이동량을 예측하는 새로운 기법을 제시하고 하와이 Kailua 해빈의 단면 관측 자료와 강릉 일대 해안선 관측 자료를 이용하여 연안 표사의 이동량 양상을 규명한다.

• 한국환경과학회지
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• 제13권3호
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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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• 제29권12호
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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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• 제1권2호
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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.

• 대한화학회지
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• 제28권3호
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• pp.170-175
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• 1984

Dibenzo-18-crown-6(DBC) 및 dicyclohexyl-18-crown-6(DCC)를 이온의 운반체로 하는 여러 유기액체막을 통해 수소이온의 운반속도를 25$^{\circ}$C에서 측정하였다. 운반속도는 용매의 유전상수에 크게 영향을 받는데 이를 액체막 내부에서 이온 화학종이 가진 Born의 포텐셜 에너지 장벽을 들어 고찰하였다. 또한 음이온의 크기도 운반속도에 영향을 주었는데 이는 Born식으로 부터 새로이 유도된 이론적인 결과와 잘 일치하였다.

• 한국수자원학회논문집
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• 제37권12호
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• pp.1033-1041
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• 2004

현장에서 교란하지 않고 채취한 유사 시료의 침식률을 측정한 결과를 직접 활용하여 침식률을 계산하는 2차원 유사이동 수치모형을 수립하고, 적용성을 검토하기 위하여 미국 팍스강에서 홍수시 유사 수송과정을 모의하였다. 큰 전단응력 하에서도 침식률 측정이 가능한 Sedflume을 사용하여 현장에서 채취된 시료의 침식률이 깊이별, 전단응력 별로 측정되었다. 수치모형은 침식률 측정자료를 모형에서 직접 사용하며, 부유사와 소류사 이동을 모두 고려한다. 개발된 모형은 1차원 직선수로에서 유사수송에 대해 검증되었다. 홍수시 팍스강의 유사 수송과정을 모의하고 부유사 농도의 시간변화에 대해 검증한 결과, 모의결과가 관측치와 잘 일치하여 현장 침식률 값을 직접 사용하는 모형이 효과적임을 확인할 수 있었다.

• 대한화학회지
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• 제41권2호
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• pp.77-81
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• 1997

거대고리 리간드인 1,12-diaza-3,4;9,10-dibenzo-5,8-dioxacyclopentadecane$(NtnOenH_4)$와 1,12,15-triaza-3,4;9,10-dibenzo-5,8-dioxacyclo-heptadecane$(NdienOenH_4)$를 운반체로 포함한 클로로포름 액체막을 통한 운반속도는 Ni(II)$({\Delta}Gp)$값을 구하여 본 결과, 운반속도의 순위는 전이금속 양이온들이 갖는 분배수화 자유에너지의 음의 값의 크기에 비례함을 알 수 있었다.

• 한국항해학회지
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• 제13권1호
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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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• 제20권2호
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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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• 제22권4호
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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.