• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.198-201
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• 2001

In-situ flushing의 적용에 따른 농도 저감이 생물학적 분해에 미치는 영향을 알아보기 위하여, 초기농도 13mg/kg dry soil과 3mg/kg dry soil인 토양을 생물학적으로 처리한 결과 제거효율은 각각 86% 및 81%였으며, 두 가지 토양 모두 24시간 이후에는 미생물에 의한 작용이 크지 않은 것으로 나타났다. 이것은 토양상에서 용액상으로의 미생물에 의한 작용이 크지 않은 것으로 나타났다. 이것은 토양상에서 용액상으로의 물질전이 속도가 율속 단계로 작용하고 있기 때문이라 생각된다. 토양에 잔류하는 계면활성제가 생물학적 분해에 미치는 영향을 본 결과, 잔류하는 계면활성제에 의해 물질전이 속도가 향상되어 생분해가 지속적으로 일어났으며 초기농도 3mg/kg dry soil인 경우 120시간이 경과한 후 89%의 제거효율을 나타내었다. 계면활성제와 보조용매가 동시에 잔류하는 경우에는 계면활성제에 대한 순응기간이 보다 길어지는 것을 알 수 있었으며, 메탄올과 에탄올의 경우 각각 84%의 제거효율을 나타내었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1400-1407
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• 2005

There are a number of approaches to in situ remediation that are used at contaminated sites for removing contaminants from the contaminated zone without excavating the soil. These include soil flushing, dual phase extraction, and soil vapor extraction. Of these techniques, soil flushing is the focus of the investigation in this paper. The concept of using prefabricated vertical drains(PVDs) for remediation of contaminated sites with fine-grained soils is examined. The PVD system is used to shorten the drainage path or the groundwater flow and promote subsurface liquid movement expediting the soil flushing process. The use of PVDs in the current state of practice has been limited to soil improvement. The use of PVDs under vacuum conditions is investigated using sample soil consisting of silty sand.

• 한국환경복원기술학회지
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• 제10권5호
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• pp.76-86
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• 2007

For the purpose of ground improvement by means of soil flushing systems. Incorporated technique with prefabricated vertical drains have been used for dewatering from fine-grained soils. The laboratory model tests were performed by using the flushing tracer solutions for silty soils and recorded the tracer concentration changes with the elapsed time and flow rates. A mathematical model for prediction of contaminant transport using the PVD technology has been developed. The clean-up times for the predictions on both soil condition indicate more of a sensitivity to the dispersivity parameter than to the extracted flow rate and vertical velocity parameters. Based on the results of the analyses, numerical analysis indicate that the most important factor to the in-situ soil remediation in prefabricated vertical drain system is the effective diameter of contaminated soil.

• 한국해양학회지
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• 제10권2호
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• pp.67-75
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• 1975

Tidal Flushing at the entrance channels of tidal bay or estuary in the central western coast of Korea; Gum River Estuary, Garorim Bay, Asan Bay, and Yeomha Estuary were studied with the recent data of current surveys measured by curret meter at three or five anchored stations along the section for one or two tidal periods at mean spring tide. Equilibrium relationship between tidal prism at mean spring tide and minimum flow area below the mean sea level of the channel in alluvial material was found as of O'Brien's (1931, 1969) study. Bed load transport in the tidal channel is balanced with the tidal flushing ability having a mean velocity of about 0.75m/sec or maximum velocity of about 1.25m/sec for a half tidal cycle over the section at mean spring tide which fairly agree with Brunn's study(1955, 1957). flushing actions for different hydraulic depth( mean depth) and bed material size in the channel were reviewed and found that it depend to a minor extent on the factors.

• International Journal of Internet, Broadcasting and Communication
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• 제14권3호
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• pp.161-170
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• 2022

Recently, NAND-type flash memory has been regarded to be new promising storage media for large-scale database systems. For flash memory to be employed for that purpose, we need to reduce its expensive update cost caused by the inablity of in-place updates. To remedy such a drawback in flash memory, we propose a new flash-aware buffering scheme that enables virtual flushing of dirty pages. To this end, we slightly alter the tradional algorithms used for the logging scheme and buffer management scheme. By using the mechanism of virtual flushing, our proposed buffering scheme can efficiently prevent the frequenct occureces of page updates in flash storage. Besides the advantage of reduced page updates, the proposed viurtual flushing mechanism works favorably for shorneing a recocery time in the presense of failure. This is because it can reduce the time for redo actions during a recovry process. Owing to those two benefits, we can say that our scheme couble be very profitable when it is incorporated into cutting-edge flash-based database systems.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.576-578
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.406-406
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• 2005

• 임상간호연구
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• 제20권3호
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• pp.326-336
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• 2014

Purpose: The purpose of this study was to compare the effectiveness of heparin and 0.9% normal saline solution flushing for maintaining patency of non­tunneled central venous catheters in patients with surgery. Methods: A randomized controlled clinical trial was performed. Fifty­eight patients were prospectively enrolled and fifty-four patients were completed the study. The heparin group consisted of 30 patients given 100u/ml diluted heparin flushing and the normal saline group consisted of 24 patients with 0.9% sodium chloride flushing. Results: There was no significantly difference in occlusion between the heparin group and the normal saline group in non­tunneled central venous catheters' occlusion. Also there was no difference between these two groups in catheter­related infections. Conclusion: Flushing with 0.9% normal saline is as effective as flushing with heparin solution in maintaining the patency of non­tunneled central venous catheters. In this study, however, the duration of central line use was short and the infection occurrence was little. Further studies are warranted with a larger sample size at multiple centers.

• 한국환경과학회지
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• 제25권8호
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• pp.1087-1095
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• 2016

The concepts of residence time and flushing time can be used to explain the exchange and transport of water or materials in a coastal sea. The application of these transport time scales are widespread in biological, hydrological, and geochemical studies. The water quality of the system crucially depends on the residence time and flushing time of a particle in the system. In this study, the residence and flushing time in Gamak Bay were calculated using the numerical model, EFDC, which includes a particle tracking module. The average residence time was 55 days in the inner bay, and the flushing time for Gamak Bay was about 44.8 days, according to the simulation. This means that it takes about 2 months for land and aquaculture generated particles to be transported out of Gamak Bay, which can lead to substances accumulating in the bay. These results show the relationships between the transport time scale and physical the properties of the embayment. The findings of this study will improves understanding of the water and material transport processes in Gamak Bay and will be important when assessing the potential impact of coastal development on water quality conditions.

• 한국산림과학회지
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• 제87권2호
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• pp.194-200
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• 1998

천연림내의 참나무류와 자연 수분된 종자 및 인공적인 종간 교잡 종자를 양묘해서 키운 묘목의 종 및 잡종 간의 개아기(開芽期) 차이를 조사하였다. 금산연습림(禁山演習林)의 천연림에서 개아(開芽)는 Q. crispula > Q. anguste-lepidota > Q. takatorensis ${\fallingdotseq}$ Q. serrate > Q. dentata 순으로 진행되었다. 자연 수분된 종자로 양묘한 묘목에서는 Q. aliena ${\fallingdotseq}$ Q. crispula > Q. anguste-lepidota > Q. takatorensis ${\fallingdotseq}$ Q. serrate > Q. dentata 순으로 개아(開芽)하였다. 종간 교잡의 묘목에서 $F_1$의 개아기(開芽期)는 양친종의 사이에 속했지만, 개아기(開芽期)가 빠른 양친의 영향을 보다 크게 받는 것으로 나타났다. 종간교잡의 결과를 통해서 추정할때 참나무류의 개아기(開芽期)의 빠르고 느린 특성은 유전적인 지배를 받아, 후대에 유전되는 것으로 사료된다.