• 물과 미래
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• 제28권3호
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• pp.159-173
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• 1995

본 연구는 도시화로 인해 야기되는 도시유역의 홍수재해를 경감시키기 위하여 우수유출억제대책으로 유역내의 일부에 지체저류시설을 설치하는 방안을 검토하는 것으로서, 도시화의 진전상태에 따라 도시유역의 수문응답특성을 파악하고 적정 지체저류시설의 위치와 크기를 결정하기 위해 유역면적이 각각 1$\textrm{km}^2$, 10$\textrm{km}^2$인 가상의 소유역 및 전유역과 실제 도시유역을 대상으로 해석하였다. 강우빈도, 토지이용단계, 배수패턴, 허용방류량의 규모에 대해 도시화의 진전상태에 따른 수문응답특성을 파악하였으며, 실유역으로는 서울특별시의 잠실 2 및 성내 1 유수지 배수구역을 선정하여 지체저류시설의 크기와 위치를 나타내는 회귀식을 유도하여 제시하였다.

• 한국토양비료학회지
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• 제44권1호
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• pp.8-14
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• 2011

The effect of flooding and soil salinity on the growth of yam (Dioscorea batatas) were studied on the experimantal site temporally established in the south-eastern part of Saemangeum Reclaimed Tidal Land (near Gwanghwal myun, Gimjae-gun, Jellabukdo, Korea). Yam seedlings planted by using aerial bulblet as alternative of sliced tubers, were grown for 20-days and transplanted in black-vinyl mulched ridges (about 20 cm in height) at 70cm interval by $20{\times}60cm$ spacing in the $4^{th}$ of May, 2010. Soil salinity was maintained at lower than 1.2 ds $m^{-1}$ during the growing period and did not result to salt injury in all plants. However, flooding injury very seriously led to plant death and plant mortality rates at $67{\pm}21$ and $82{\pm}9%$ of yam plants in the compost and no compost treatment, respectively, died by heavy flooding during the rainy summer season. The main reasons of the flooding injury included the decreased rainfall acceptable capacity (RAC) after the rising of water table and a slowdown of water infiltration rate after the formation of an impermeable soil crust in the furrow bottom with continuous and heavy downpour during the rainy summer season. The effect of compost treatment was not statistically observed because of the severe spatial difference caused by wet injury, although yam tuber yield was higher at 30 kg $10^{-1}$ in the compost treatment than in the no-compost treatment at 20 kg $10^{-1}$. However, the size of tuber ranged at 1.23 to 1.60 cm in diameter and 3.7 to 5.0 cm in length in all both treatment, which means they are still reproducible for the next cropping season. Conclusively, proper counter-flooding measure and soil salinity control critically important for successful yam production in Saemangeum Reclaimed Tidal Land.

• 한국지리정보학회지
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• 제7권3호
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• pp.108-117
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• 2004

임동 유역은 지질 및 토지피복 상태가 토사유실에 취약한 특성을 가지고 있어, 강우발생시 토사유입으로 호소내 수질오염에 큰 영향을 주고 있으며, 특히 이러한 호소내 수질문제의 원인으로 저수지 사변의 토사유실 가능성이 제기되고 있다. 본 연구에서는 저수지 사면에서 발생하는 토사유실 기여율을 평가하기 위해 최근 GIS 및 위성영상과의 연계가 가능한 RUSLE 모형을 선정하였으며 사면에서 발생하는 토사유실 정확도에 큰 영향을 주는 사연의 범위와 폭 그리고 사면상태를 DB로 구축하기 위해 현지조사를 실시하였다. 임동유역에 대한 토사유실량과 비교하여 저수지 사면에서 발생하는 토사유실량과의 영향을 분석한 결과 약 2.64%로 나타났다. 따라서 이러한 결과를 볼 때, 임동 유역의 토사유실량에 비해 저수지 사면의 토사유실 영향은 상대적으로 낮은 것으로 평가되었다.

• 한국환경보건학회지
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• 제24권1호
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• pp.62-69
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• 1998

It has been studied that the measurement of odor component emission at confectionery manufacture. The objects of this study were to investigate reduction of offensive odor. The survey effects of odorous materials are presented as follows. The countermeasure of operating process is to minimize sludge sediment in each unit facility. Especially, in summer, we have to clean the sludge frequently, because anaerobic decomposing is likely to occur easily. The sludge or scum from sedimentation tank pond, and floating tank should be treated quickly. We should avoid overloading operation. In the case of overloading, dissolved oxygen should be increased, the quality of wastewater input should be decreased. When dried cakes from condense tank or floating tank are left in treatment plant, we should cover, to prevent diffusion of smell with masking materials. The seasonal condition of operating should be fixed and the kind of coagulants should be changed because the wastewater in each season have different loading rates and organic materials. Odorous materials are very sensitive to the seasonal temperature variation. Especially, when the amount of rainfall is small and the high temperature of maintenance in long periods, air diffusion rate is large, so odorous materials can make great effect on surroundings comparision with other periods. To reduce odorous gas, as short term method, we had better take ceramic addition method. Especially, in summer we should take ceramic addition method. Also, as long term method, the size of wastewater treatment facility is the most important in the normal operating of wastewater treatment facility. But wastewater treatment facilities in this factory are too old, treatment process is old fashion, and the size is too small. So, large wastewater quantity to treat in summer. As results, the expansion of wastewater treatment facility and the process of improvement are required. Restriction level of odor was exceed. As it is overloaded in summer, the basis cause of odor is that the size of wastewater treatment facility is small. The prediction of air quality equilibrium density variation show that the odorous materials from working place are Amine materials whose smell strength is about 2.5(a little strong degree). We can suppose that in summer is sensitive to temperature variation, smell strength is larger as to reduce the origin of odor. We must expand wastewater treatment facility and improve the process A.S.A.P.

• 한국환경과학회지
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• 제25권4호
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• pp.535-542
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• 2016

This study was conducted to investigate effects of waterlogging on the growth, physiological responses, and yield of Kimchi cabbage. The growth of Kimchi cabbage with applied optimized air temperature (set to $20^{\circ}C$) was greater than those with high air temperature (set to $30^{\circ}C$) and the growth significantly decreased by severe waterlogging treatment. The net photosynthetic rate of outer leaves on one hour after waterlogging treatment was higher at 72 hours waterlogging treatment in $20^{\circ}C$ and lower at 24 hours of waterlogging treatment in $30^{\circ}C$. The root activity was decreased by the elevation of waterlogging periods in $20^{\circ}C$ treatment and lower by the short of waterlogging periods in $30^{\circ}C$ treatment. The ratio of formality with non-waterlogging treatment was approximately 64% under $20^{\circ}C$ air temperature and that of range was from 16 to 30% under $30^{\circ}C$. The yield under $20^{\circ}C$ showed higher than that under high air temperature. The non-waterlogging treatment in $20^{\circ}C$ had 4,463 kg/10a, which was the greatest among all treatments, while yields of non-waterlogging treatment at $30^{\circ}C$ were significantly low as 1,082 kg/10a. Results suggested that additional drainage work should be needed to overcome waterlogged conditions of open field during heavy rainfall and should be drainage as soon as possible if there are waterlogging.

• 한국기계가공학회지
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• 제19권4호
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• pp.58-64
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• 2020

Large-scale flooding due to extreme weather and typhoons causes heavy damage. This is especially true in urban areas where accumulated debris prevents the smooth drainage of rainwater in sewage facilities such as rain gutters installed near roads. In this study, to improve the drainage performance and effectively remove foreign substances by applying the dust screen used in rivers, the rain gutter with Coanda effect was simulated and compared with the experiment. The simulation was performed by setting the parameters to the fillet radius R₁ and R₂ at the top of the screen filter, the fillet radius R₃ at the bottom of the screen filter, and the height H of the gap W from the bottom. W is the gap at the backside of screen filter which is applied to stimulate the Coanda effect. According to the simulation results, the highest drain performance was 87.99% derived from R₁= 30mm, R₂= 5mm, R₃= 85mm, H= 75mm, and W= 2mm. The error rate of simulation results refer to the 4.89%~7.36% compared to the experimental results. In the future, by considering the slope according to the installation environment, the simulation results can be applied to the actual roadside to help prevent flood damage.

• 생태와환경
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• 제49권2호
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• pp.130-141
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• 2016

This study was conducted to elucidate the structure of river ecosystem in the watershed of the Seom River and Hoengseong Reservoir located in Hoengseong of Kangwon Province from February to October 2007. Topics of the survey were mainly rainfall, discharge, water quality in abiotic factors and attached algae, benthic macroinvertebrates, fish, birds and mammals of flora and fauna in a biotic factors, respectively. Specifically, the Seom River could be seen as a typical flow rate of the stream is controlled to the effect of the dam. Basic water qualities were great to seasonal effects, it was relatively clean. Diatom Achnanthes, Cymbella, Gomphonema, and Navicula were distributed predominantly in the periphytic algae. Benthic macroinvertebrates were mostly aquatic insects and freshwater shellfish, the aquatic insects were abundant Ephemeroptera and Trichoptera. Freshwater fish was the dominant Zacco platypus, fish species varied toward the downstream. Birds were mainly observed in four species, and species Egretta garzetta, which was distributed in a wide area of the Seom River. In mammals, Lutra lutra of Mustelidae was identified that the number of inhabit widely. In aspects of the ecological trophic level, the Seom River was maintained at a relatively stable state in the producer and the consumer relationship. The results of this study will expected to be utilized as a useful data for understanding the structure and function of the lotic and lentic ecosystems.

• 한국환경과학회지
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• 제26권12호
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• pp.1321-1331
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• 2017

This study reviewed the applicability of the existing flood discharge calculation method on Jeju Island Han Stream and compared this method with observation results by improving the mediating variables for the Han Stream. The results were as follows. First, when the rain-discharge status of the Han Stream was analyzed using the flood discharge calculation method of the existing design (2012), the result was smaller than the observed flood discharge and the flood hydrograph differed. The result of the flood discharge calculation corrected for the curve number based on the terrain gradient showed an improvement of 1.47 - 6.47% from the existing flood discharge, and flood discharge was improved by 4.39 - 16.67% after applying the new reached time. In addition, the sub-basin was set separately to calculate the flood discharge, which yielded an improvement of 9.92 - 32.96% from the existing method. In particular, the steepness and rainfall-discharge characteristics of Han Stream were considered in the reaching time, and the sub-basin was separated to calculate the flood discharge, which resulted in an error rate of -8.77 to 8.71%, showing a large improvement of 7.31 - 28.79% from the existing method. The flood hydrograph also showed a similar tendency.

• Asian-Australasian Journal of Animal Sciences
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• 제15권8호
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• pp.1110-1114
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• 2002

The animal production sector in Jordan is characterized by shortages of locally produced feedstuffs derived from rangeland, forage plants or from human food crops as by products. This is exacerbated by insufficient rainfall, overgrazing, early grazing and high stocking rate. Thus, subject to these constraints, other technological improvements are highly desirable to meet the needs of crop growth and animal production. Alternative adapted technologies are also desirable in order to meet the increased demand for red meat in relation to population growth along with the changes in the price subsidy for feedstuff. The technologies are those, which have been introduced to the animal production sector, obtained in agricultural research stations besides on-farm demonstrations. They include technologies suited for increasing birth and twining rates, synchronizing the mating period, introducing the early weaning method, and animal feed and sheep production. Economic assessments conducted in this study demonstrate promising results of hormonal and nutritional practices in improving production efficiency of Awassi sheep in Jordan. Jordanian published data between 1991 and 1998 were used. The examined practices were: 1) use of PMSG in estrus synchronization in ewes, 2) introduction of early lamb weaning program, 3) supplementation with $AD_3E$ for ewes and 4) the use of agro-industrial feed block as a feed supplement for grazing lambs. Production data were then subjected to partial budgeting for economical evaluation. The use of PMSG outperformed the control groups in fertility and net returns per ewe by US$ 8.36/ewe. The early weaning of lambs increased the net returns by US$ 3.90/lamb. The injection with vitamin $AD_3E$ showed an average additional net return of US$ 5.66/ewe. Feeding agriculture by-product blocks improved weight gain in the feed block groups and resulted in additional net returns of US$ 3.5/lamb. The economic viability and reproductive performance indicators demonstrate that efforts should be undertaken to disseminate these new practices in the development program.

• 한국수자원학회논문집
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• 제42권9호
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• pp.737-745
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• 2009

국내 도시화 시험유역에 대한 기존 토사유출공식의 적용 가능성을 검토하기 위해 도시 시험유역의 실측자료와 모의기법 적용결과를 비교.분석하였다. 적용된 토사유출량 산정 모의공식으로는 개정범용토양손실공식(RUSLE - Revised Universal Soil Loss Equation), 수정범용토양손실공식(MUSLE - Modified Universal Soil Loss Equation)을 활용하였다. 시험유역은 유역면적 약 3.81 $km^2$로 면적대비 56 % 정도가 도로 및 포장 등으로 도시화가 진행된 도시 시험유역을 선정하여 자동 강우 및 수위계측기를 이용하여 지난 3년간 연속적으로 수문자료를 축적하였다. 또한 계측지점에서의 유출량별 소류사 및 부유사 실측을 통하여 유량-유사량 관계곡선을 개발한 후 호우사상별 유역으로 부터의 토사유출량을 산정하였다. 실측된 강우 및 유량 자료를 활용하여 모의한 토사유출량과 실측한 토사유출량을 비교한 결과 RUSLE를 적용한 모의결과가 실측 토사유출량과 근접한 결과를 제시하였으나 상관계수가 낮아 적용에 세심한 주의가 요구됨을 알 수 있었다. 반면, 실제 유출수문곡선을 MUSLE기법에 적용하여 모의한 토사유출량과 실측 토사유출량의 상관관계는 우수한 예측결과를 보였으나 보정계수의 적용이 필요함을 확인하였다.