• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.144-144
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• 1998

The physiological responses caused by exposure of high- and low-level lead exhibit different phase. Low-level lead continuous hypertension, but high-level lead can in the development of hypertension. In this study it was tested which difference can be caused as lead levels and, if it can be caused, whether hematological changes are related with the hypertensive effects induced by different levels of lead exposure was tested. Lead intoxication in male SD rats was induced by exposure through drinking water containing 50, 200 and 1000 ppm lead (as lead acetate). The animals of control group was supplied drinking water containing sodium acetate ad libitum. The number of each animal group was 10. Systolic blood pressures were measured in the unanesthetized state by the tail-cuff technique at 0, 3, 7 and 16 weeks. RBC, WBC, MCV, hemoglobin, hematocrit and whole blood viscosity levels were examined.

• 한국환경생태학회지
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• 제24권2호
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• pp.186-193
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• 2010

2006~2008년 동안 새만금 간척지에서 조성된 인공 염생식물 군락지와 새만금 방조제 배수갑문 수위 관리의 연관성을 밝히기 위해 배수갑문 수위특성 및 사유, 염생식물 군락지의 공간적인 분포와 형성 과정, 수위변화에 따른 염생식물 분포공간분석을 시도하였다. 배수갑문 수위조절의 특성을 분석한 결과, 파종 후 생장기의 평균수위와 연평균 수위와의 차이는 유사했으며, 연간 최저수위 및 최고수위가 파종 후 생장기에 나타났다. 3년동안 4,315만$m^2$에 염생식물 군락지가 형성되었으며 총 2,673만$m^2$에 대해 인공적인 염생식물 군락 조성이 시도되어 291만$m^2$을 제외한 표고 약 1m 이상의 2,382만$m^2$(89.1%)에 염생식물 군락지가 형성된 것으로 추정되었다. 파종지역 염생식물 군락지 형성에서 해수의 평균수위나 최저수위보다도 최고수위가 결정적인 요인으로 작용하였으며, 경운 및 토양 피막 여부가 군락지 형성의 2차적인 요인으로 작용한 것으로 보인다.

• 한국환경보건학회지
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• 제21권1호
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• pp.7-20
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• 1995

The aims of this study are to enhance the students' knowledge of the drinking water and its reliability by investigating drinking water situation on the drinking water. The results are as following 1. Status and drinking behavior about school drinking water (1) 97.82% of the schools are using the tap water as the resource of drinking water. (2) 46 schools are in possession of water tank and 18 schools of them are using the water tank as the resource of drinking water. The clearing and sanitization of the tank are carried out once in a year with hypochloronatrium by the low-level officials. (3) 51.28% of the schools are providing the students with drinking water and 75% of them with boiled water. The drinking water supply managers are low-level officials, nurse teachers, and dietitian. 2. Analysis of the drinking water quality (1) Most of the drinking water provided by the school are tap water 35.8%, barely tea 5.85%, filtered water 6.3%, ground water 1.1% and all turned out to be suitable for drinking. (2) The drinking water carried from home turned out to be unsuitable for drinking except pH criterion, especially the test of APC(Aerobic Plate Count) and Coliform group showed worse degree. These results were caused by the hygiene problem and maltreatment in water container.

• 생태와환경
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• 제50권3호
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• pp.337-354
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• 2017

남조류 Aphanizomenon속 개체군은 국내외에 널리 분포하고, 독소와 이취물질을 생산함으로써 유해조류로 잘 알려져 있어 육수생태학 분야에서 많은 관심을 갖게 된 분류군 중 하나에 속한다. 본 연구는 보령호에서 동계에 수위가 급격히 강하되면서 Aphanizomenon의 출현빈도, 강도 및 기간이 커지게 되어 이에 대한 시공간적 특성을 수문기상(1998년~2017년) 육수 (2010년~2017년)학의 관점으로 상호 비교하였다. 국내에서 Aphanizomenon은 고온기에 주로 번성하였으며, 저온기에 출현은 총 5회로서 드물었다. 보령호에서 저온기(12월~2월)에 유해조류 Aphanizomenon이 관찰된 것은 2014년부터이었고, 그 후 2017년에 최대값 $2,160cells\;mL^{-1}$를 기록하였다. 그리고 $>1,000cells\;mL^{-1}$를 초과하는 기간은 약 3개월을 넘기기도 하였다. 이것은 다름 아닌 저수온기 ($<10^{\circ}C$)에 비정상적인 수위 강하와 관련성이 컸다. 동계에 수위 강하는 유해조류의 발아 및 발생을 촉진 또는 증폭시킬 수 있는 잠재적 특성을 가지고 있었다. 따라서 후속 수질 생태학적 영향(예, 조류독소 및 이취물질)도 면밀하게 고려되어야 할 필요성이 있었다.

• 한국터널지하공간학회 논문집
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• 제18권1호
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• pp.95-107
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• 2016

도시지역에 시공되는 지하차도 구조물은 지리적 특성상 지하수위의 영향을 받기 쉽다. 그러나 지하차도 구조물 설계 시에는 일괄적인 지하수위를 적용하여 설계를 수행하는 경우가 많으며 이는 과소 또는 과다 설계를 초래할 수 있다. 따라서 본 연구에서는 보다 신뢰도 높은 지하수위 예측을 통해 지하차도 구조물의 합리적인 부력설계 방향을 제시하고자한다. 특히, 최근 친환경적인 개발 개념인 LID 기법을 도입한 투수 포장 적용에 따른 물순환 특성 변화가 지하차도 구조물에 어떠한 영향을 미치는지에 대해 검토하였다. 이를 위해 개발 전, 개발 후, 투수포장 적용에 의한 지표면 불투수 특성 변화가 침투량 및 지하수위 변화에 미치는 영향 분석과 지하차도 안정성을 검토하는 일련의 수치해석을 수행하였다. 해석결과 지표면의 변화가 지하수위 변화를 유발하고 지하 구조물 안정성에 영향을 줄 수 있음을 확인하였다. 따라서 지하차도 및 지하구조물의 최적 설계를 위해서는 지표면 유출 특성을 고려한 적절한 지하수위 예측 및 적용이 필요할 것으로 판단된다.

• 대한원격탐사학회지
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• 제31권4호
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• pp.337-346
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• 2015

Water body extraction based on backscatter information is an essential process to analyze floodaffected areas from Synthetic Aperture Radar (SAR) image. Water body in SAR image tends to have low backscatter values due to homogeneous surface of water, while non-water body has higher backscatter values than water body. Non-water body, however, may also have low backscatter values in high resolution SAR image such as Kompsat-5 image, depending on surface characteristic of the ground. The objective of this paper is to present a method to increase backscatter contrast between water body and non-water body and also to remove efficiently misclassified pixels beyond true water body area. We create an entropy image using a Gray Level Co-occurrence Matrix (GLCM) and classify the entropy image into water body and non-water body pixels by thresholding of the entropy image. In order to reduce the effect of threshold value, we also propose Water Body Texture Index (WBTI), which measures simultaneously the occurrence of repeated water body pixel pair and the uniformity of water body in the binary entropy image. The proposed method produced high overall accuracy of 99.00% and Kappa coefficient of 90.38% in water body extraction using Kompsat-5 image. The accuracy analysis indicates that the proposed WBTI method is less affected by the choice of threshold value and successfully maintains high overall accuracy and Kappa coefficient in wide threshold range.

• Journal of Advanced Marine Engineering and Technology
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• 제18권1호
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• pp.73-80
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• 1994

The water ejector is a low pressure high flow rate volumetric pump. It utilize the energy of a low mass flow, high velocity stream to induce a large mass flow, low velocity stream. In addition, it has a very good resistances to cavitation compared to the other type of pumps, and the maintenance cost is practically nil. There has been enormous energy loss to supply the upper part water of dam which has large potential energy as mere irrigation water in domestic multipurpose dam. The new type of energy saving system which developed through the present study can economizes over 950,000 kWh per year by mixing the upper part water of dam with the waste water by the large water ejector. This paper estimates the economical efficiency of the new type of irrigation water pumping system, and further more, represents the change of performance characteristics of large water ejector, which was adapted to this system, according to the fluctuation of upper water level that seasonally changes.

• 한국인터넷방송통신학회논문지
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• 제18권4호
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• pp.143-147
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• 2018

수위는 하수장, 정수장, 하천, 댐, 공장의 저장탱크 등 다양한 분야에서 측정된다. 수위측정을 위한 초음파 기기가 판매중이나 산업용으로 실험에서 사용하기는 가격이 너무 비싸다. 전자 기술의 급속한 진보로 인해 다양한 종류의 측정, 모니터링 및 제어 기능이 저렴하게 구축하는 것이 가능해졌다. 저렴한 가격으로 초음파 수위 측정시스템을 만들기 위하여 본 연구가 시작되었다. 실험용으로 사용하기 위하여 아두이노, 초음파 센서 및 온도 센서로 시스템을 구성하였다. 초음파 센서는 센서에서 수위 표면까지의 시간을 측정한다. 온도 센서는 대기 온도를 측정하며 온도 변화로 인한 소리의 속도를 보정하여 초음파 거리 측정의 정확성을 높인다. 아두이노는 측정 전반을 관리하고 수위를 계산한다. 시스템의 모든 구성 요소는 장치거치대에 조립되었다. 제안된 시스템을 가지고 실험한 결과 수위가 실측치와 매우 가까웠다. 이 시스템은 또한 저렴하며 설치 및 유지하기가 쉬워 실험용으로 적절하다.

• 한국농공학회논문집
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• 제64권6호
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• pp.13-23
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• 2022

The purpose of this study was to analyze the impact of greenhouse cultivation area and groundwater level changes due to the water curtain cultivation in the greenhouse complexes, which are mainly situated along rivers where water resources are easy to secure. The groundwater observation network in Miryang, Gyeongsangnam-do, located downstream of the Nakdong River, was selected for the study area. We classified the groundwater monitoring well into the greenhouse (riverside) and field cultivation areas (plain and mountain) to compare the groundwater impact of water curtain cultivation in the greenhouse complex. The characteristics of groundwater level changes classified by terrain type were analyzed using the observed data. Riverside wells have significant permeability coefficients and are close to rivers, so they are greatly affected by river flow and precipitation changes so that water level shows a specific pattern of annual changes. Most plain wells do not show a constant annual change, but observation wells near small rivers and small-scale greenhouse cultivation areas sometimes show annual and daily changes in which the water level drops during winter. Compared to other observation wells, mountain wells do not show significant yearly changes in water level and show general characteristics of bedrock aquifer well with a low permeability coefficient.

• 한국지역사회생활과학회지
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• 제15권1호
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• pp.105-113
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• 2004

This study investigated the synergy effects of hot water soluble extract from Eleutherococcus senticosus and dietarty carnitine on the lipid metabolism and antioxidant defense system of rats on hypercholesterol diets. Sprague-Dawley male rats were fed either a hypercholesterol diet with water or a hot water soluble extract from Eleutherococcus senticosus and dietarty carnitine. The experimental groups consisted of the control group (CO), the group supplied with hot water soluble extract from Eleutherococcus senticosus(ES), and the group supplied with hot water soluble extract from Eleutherococcus senticosus and dietarty carnitine(ESC). Eleutherococcus senticosus was extracted, made into 0.5% solution, and fed to the ES and ESC groups. A 3% carnitine diet was supplied to the ESC group. Hypercholesterol diets contained 18% beef tallow and 5% cholesterol. After 4 weeks of administering these diets, serum and liver were obtained and the level of serum lipid and the activities of GOT and GPT were measured. In addition, the level of liver lipid and TBARS and the activity of GSH-Px were measured. The results were as follows: 1) Weight gain and FER in the group supplied with hot water soluble extract from Eleutherococcus senticosus and dietarty carnitine(ESC) was low significantly(P<0.05). 2) In the groups supplied with hot water soluble extract from Eleutherococcus senticosus(ES) and the group supplied with hot water soluble extract from Eleutherocorcus senticosus and dietarty carnitine(ESC), total serum cholesterol levels were both significantly low (P<0.05,P.0.01). 3) Serum GOT activity was significantly low(P<0.05) in the group supplied with hot water soluble extract from Eleutherococcus senticosus(ES) and in the group supplied with hot water soluble extract from Eleutherococcus senticosus and dietary carnitine(ESC). There was no difference between serum GPT activity in the control group and the groups supplied with hot water soluble extract from Eleutherococcus senticosus or dietary carnitine. 4) Liver triglyceride was low (P.0.05) in the group supplied with hot water soluble extract from Eleutherococcus senticosus and dietarty carnitine(ESC). No difference was observed in other lipid composition, TBARS level, and GSH-px activity in liver between the control group and the experimental groups. In summary, the effects of hot water soluble extract from Eleutherococcus senticosus and dietarty carnitine on the lipid metabolism and antioxidant defense system (such as weight gain, FER, total serum cholesterol and liver triglyceride) were low when Eleutherococcus senticosus and dietarty carnitine were supplied simultaneously.