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        검색결과 182

        161.
        2008.10 KCI 등재 서비스 종료(열람 제한)
        This study was carried out to investigate the proper interval of water exchange according to nitrogen fertilizer level at medium saline soil which are 0.3 or more soil salinity in southwestern reclaimed saline land. The nitrogen fertilizer level were 14, 17, 20kg per 10a, and the interval of water exchange were every 3, 6, 9 days after transplanting. The summarized experimental results are as follows. The salinity were maintained as low when the interval of water exchange were every 3 or 6 days after transplanting, but salinity was highest at rooting stage, and decreased from that, so salinity were about 0.3 at panicle initiation stage or ripening stage when the interval of water exchange was every 9 days after transplanting. The rice yield were 537-552kg/10a when the interval of water exchange was every 3 days with 17-20kg/10a nitrogen fertilizer level, and 519-533kg/10a when the interval of water exchange was every 6 days with 17-20kg/10a nitrogen fertilizer level, but decreased outstandingly in the other treatments. Considering the yield and salt injury at medium saline soil at southwestern reclaimed saline land, proper nitrogen fertilizer level was 17-20kg/10a when the interval of water exchange were every 3 or 6 days after transplanting.
        162.
        2008.03 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 지표흐름 습지의 수질관리를 위하여 습지 내 오염물질을 적절히 모의할 수 있는 연속교반탱크반응기(CSTR) 모델을 구축하였다. 이 모델은 4차 Runge-Kutta법을 사용하고, 실측치와 계산치의 차이를 최소화 하는 최적화 기법으로 해를 구하며, 미국 EPA 습지 데이터베이스에 수록된 자료중 수질 및 수리자료가 충분하며, 분석이 용이한 하나의 수생대를 갖는 습지를 선택하여, 수질항목중 관심도가 높은 BOD, TSS (Total Suspend
        163.
        2007.05 KCI 등재 서비스 종료(열람 제한)
        The mechanism of water pollution in Lake Shihwa, one of highly eutrophicated artificial lakes in Korea, has been studied using a numerical 3D physical-biochemical coupled model. In this study, the model was applied to estimate the contribution of land-based pollutant load to water quality of heavily polluted Lake Shihwa. The chemical oxygen demand(COD) was adopted as an index of the lake water quality, and the spatial distribution of an average COD concentration during the summer from 1999 to 2000 was simulated by the model. The simulated COD showed a good agreement with the observed data. According to reproducibility of COD, the highest levels between 8 and 9 mg/L were shown at the inner site of the lake with inflow of many rivers and ditches, while the lowest was found to be about 5 mg/L at the southwestern site near to dike gate. In the prediction of water quality of Lake Shihwa, COD showed still higher levels than 3 mg/L in case of reduction of 95% for land-based pollutant load. This suggests that the curtailment of land-based pollutant load is not only sufficient but the improvement of sediment quality or the increase of seawater exchange should be considered together to improve a water quality in Lake Shihwa.
        164.
        2007.04 KCI 등재 서비스 종료(열람 제한)
        This study estimated response of water quality and pollutant behavior according to the discharge and reuse of treated wastewater by three-dimensional eco-hydrodynamic model, and suggest plan that water quality management and environmental restoration in the coastal area including urban stream of Yeosu, Korea. Dispersions of low-saline water and COD by treated wastewater loads (design facility capacity, about 110,000 m3/d) were very limited in near of effluent site. Nutrients, however, increase compared to the other water quality factors, especially total nitrogen was very sensitive to input loads. When reuse some of treated wastewater to Yeondeung stream, nitrogen was big influence on estuarine water quality. Although current characteristics of treated wastewater such as discharge and water quality were negligible to the change of marine environment, effluent concentration of COD, TN and TP, especially 40% of TN, are reduced within the allowable pollutant loads for satisfy environmental capacity and recommended water quality criteria. Also, controls of input point/non-point sources to Yeondeung stream and base concentration of pollutants in coastal sea itself are very necessary.
        165.
        2007.02 KCI 등재 서비스 종료(열람 제한)
        Water pollution in enclosed water bodies such as lake and river has become a serious problem over the world. Domestic wastewater is responsible for more than 60 % pollution load in public water area in Korea. Effluent of the treated domestic wastewater at low removal level is abundantly fed rivers and lakes and thus be an serious cause of lake pollution. Therefore, effective implement of domestic wastewater treatment in basin of lake and river must be prepared. The septic tank is one of the effective domestic wastewater treatment equipment and used in individual treatment for a unit of household. The purpose of septic tank as biological treatment system is simultaneously to remove BOD, T-N, T-P and reduce turbidity from influent. Accordingly, the appropriate control of functional microorganisms is important subject for the establishment of stability and economy of the biological treatment method. Especially, microanimals as a high-ranked microorganisms of food-chain are important, because microanimals control the other microorganisms especially various bacteria and effect on function of treatment. Therefore, it is necessary that functional predator like rotifers are attached in wastewater treatment process. In this study, the methods for attachment high density the rotifer to and improvement of transparency in the effluence by a dense rotifer was examined using laboratory scale biological treatment reactor simulated septic tank and real one.
        166.
        2006.10 KCI 등재 서비스 종료(열람 제한)
        90년대초 품질경영 시스템을 시작으로 98년 안전경영 시스템, 그리고 2002년 ISPS Code 발효에 따른 보안시스템까지 해운항만업체는 필요에 따라 또는 외부적 요인에 의해 최근 10여년에 걸쳐 경영시스템에 몰입하게 되었다. 이러한 경영모델, 협약, 코드는 일부 또는 전부의 도입 및 시행으로 해운항만관련회사에 경영시스템으로 자리 잡아 상호 유기적인 연관성을 갖고 직 간접적으로 밀접한 상호작용을 하고 있다. 이들 각각의 시스템에서 공통적으로 사용되는 요건들 중 개선여지가 필요하다고 판단되는 사항에 대해 설문조사를 하고 그 결과를 분석하여 시스템 도입에 따른 요건들의 문제점을 파악하여, 가장 효과적인 시스템 개선방안을 제시하는데 본 연구목적을 두고 있다.
        168.
        2005.12 KCI 등재 서비스 종료(열람 제한)
        1) 현미 품위는 무경운 짚 피복 벼 작부체계(SMNTRCS)와 무경운 짚 피복 벼-자운영 작부체계(SMNTRVCS)가 관햄 벼-보리 작부체계(CRBCS)와 관행 벼 작부체계(CRCS)보다 좋은 경향을 나타내었다. 백미 품위는 SMN TRCS에서 가장 우수하였다. 2) Mg와 K의 함량은 SMNTRVCS에서 가장 높았으며 Na 함량과 Mg/K는 CRCS에서 가장 높게 나타났다. 3) 단백질함량은 SMNTRCS에서 가장 높았으며, SMNTRVCS, CRBCS 및 CRCS순으로 감소하였다. 아밀로스함량은 SMNTRVCS에서 다른 작부체계에 비해 높게 나타났다. 4) 알카리붕괴도는 1.2~% KOH농도에서 작부체계별 품종간 변이가 가장크게 나타났다. 모든 KOH농도에서 알카리붕괴도는 CRBCS에서 가장크게 나타났으며, CRCS가 가장 낮았다. 5) 양질미 생산을 위해서는 유기물 투입으로 질소시비량을 줄일 수 있는 작부 체계인 SMNTRCS 및 SMNTRVCS가 가장 유리 할 것으로 사료된다.
        169.
        2004.06 KCI 등재 서비스 종료(열람 제한)
        본 연구는 남서해안 간척지에서 토양 염농도(저염; 0.1%, 중염; 0.3∼0.4%)별로 쌀 품질 향상을 위한 적정 질소 시비량을 구명하기 위하여 시험한 결과를 요약하면 다음과 같다. 1.유추분화기의 초장은 질소 시비량이 많을수록 컸고, 토양염농도간에는 저염 토양에서 켰다. 2. 출수기는 저염 토양에서는 표준비인 N20kg/10a에 비해 N8-N16kg/10a까지는 같았으나 N24kg/10a에서는 1일 늦었고, 중염 토양에서는 N8-N16kg/10a 까지는 1일이 삘랐고 N24kg/10a에서는 같았으며, 토양 염농도간에는 저염 토양에서보다 중염 토양에서 4일 정도 늦었다. 3. 질소시비량이 많을수록 간장이 크고, 포장도복이 심했다. 4. 저염 토양에서 질소시비량이 많을수록 m2 당 립수는 많았으나 등숙비율이 낮아져 발 수량은 N12kg/10a이상에서는 유의차가 없었으며, N12kg/10a이하에서 현미의 완전미율이 높고 단백질 함량이 낮았다. 5.중염 토양에서는 질소시비량이 많을수록 m2 당 립수가 많고 등숙비율이 비슷하여 발 수량은 질소시비량이 많을수록 높았으나 N20kg/10a 이상에서는 유의차가 없었고, 현미의 완전미율과 단백질함량은 질소시비량간에 비슷하였다. 따라서 남서해안 간척지에서 쌀 수량 및 미질 등을 고려해 볼 때, 저염 토양에서는 N12kg/10a, 중염 토양에서는 N20kg/10a이 적당할 것으로 생각된다
        170.
        2003.03 KCI 등재 서비스 종료(열람 제한)
        In this study, the material cycle model was applied to suggest alternative management of water quality for Jeju Harbor. The distribution of COD, DIN (dissolved inorganic nitrogen) and DIP (dissolved inorganic phosphorus) concentrations was reasonably reproduced by simulations on the model area of the Jeju Harbor using a material cycle model. The simulations of COD, DIN and DIP concentrations were performed under the conditions of 20~100% pollution loadings reductions from pollution sources. In case of the 100% reduction of the input loads from Sanzi river, concentrations of COD, DIN and DIP were reduced to 39%, 78% and 52%, respectively at Jeju harbor. In contrast, in case of the pollutant loadings reductions from sediment, the effect of DIN and DIP reduction relatively seemed to increase around the center of study area. The 95% reduction of the pollutant loadings from river and sediment is required to meet the COD and nutrients concentration of second grade of ocean water quality criteria.
        171.
        2003.03 KCI 등재 서비스 종료(열람 제한)
        The purpose of this study is to investigate the characteristics of water quality in Jeju harbor and to estimate pollutant loadings discharged into Jeju Harbor. To know characteristics of water quality in Jeju harbor and pollutant loadings of Sanzi river, we have investigated from August, 2000 to May, 2001. The results showed that the concentrations of COD, DIN and DIP were in the range of 1.00~4.85㎎/L (mean 2.15㎎/L), 2.14~74.0㎍-at/L(mean 12.20㎍-at/L) and 0.52~4.00㎍-at/L(mean 1.18㎍-at/L), respectively. These values were under Ⅲ class of seawater quality criteria. The ratio of nitrogen to phosphorus was lower than 16 except for Station 1 in Jeju harbor. Therefore, nitrogen was playing an important role in phytoplankton growth as limiting factor in Jeju harbor. The mean values of eutrophication index were exceeding 1, which was the eutrophication criteria. The results of estimating pollutant loadings at Sanzi river are 0.30 ton/day for COD, 300㎏/day for DIN and 18.0㎏/day for DIP, respectively.
        172.
        2002.12 KCI 등재 서비스 종료(열람 제한)
        보리의 산물처리 확대를 위한 기초자료를 제공하고자 미곡종합처리장을 이용한 보리 산물처리시 품질변화와 생력효과를 조사 분석한 결과는 다음과 같았다. 1. 정립율은 2.5-2.2mm의 비율이 가장 많았으며, 건조방식에 따른 차이는 없었다. 2. 경도는 건조방식에 따른 차이는 없었고, 색도는 산물건조와 관행인 천일건조와 차이는 없었다. 3. 흡수율은, 고형용출물, 퍼짐성 등의 취반특성은 건조방식에 따른 차이는 없었다. 4. 산물처리에 의하여 관행의 ha당 46시간에 비하여 21시간으로 54.3%의 생력효과가 있었고, 수확 후 관리는 54.3% 생력화되었다. 5. 산물처리로 수확 후 관리노력이 관행에 비하여 ha당 25시간이 절감되어 101,83원의 경영비 절감효과가 있었다
        173.
        2002.10 KCI 등재 서비스 종료(열람 제한)
        하천에서 동수역학적 흐름해석 및 오염물질의 이송-확산 해석을 수행하고, 불확실도 해석기법을 이용하여 신뢰도 해석을 수행할 수 있는 2차원 수질관리모형인 UUWQM(Unsteady/Uncertainty Water Quality Model) 모형을 개발하였다. 본 모형의 실제 적용을 위해 낙동강 중류부의 성주에서 현풍까지 35km 구간에 대하여 2차원 동역학적 흐름해석과 수질해석이 실시되었다. 민감도 분석을 통해 수질모형에 기여도가 큰 입력변수들을 결정하였
        174.
        2002.06 KCI 등재 서비스 종료(열람 제한)
        본 연구는 부산항 컨테이너 터미널이 품질경영을 통한 경쟁력을 향상시키기 위하여 어떠한 서비스 품질경영활동들에 노력을 집중해야 하는지에 대한 실증적인 연구이다. 품질경영활동의 공통된 요소들과 이 요인들 간의 인과관계를 분석하여 결과를 해석하고 항만서비스 품질 경영 관리에 미치는 관리적 시사점을 제시하고 있다. 자료수집은 부산항 컨테이너 터미널의 종사자 170명을 대강으로 설문지와 개인면담을 통해 이루어졌으며, 측정변수의 신뢰성과 타당성을 분석하기 위해 Cronbach's α계수와 요인분석을 이용하였다. 그리고 품질경영시스템의 구성개념인 풀질경영의 원천과 활동, 그리고 성과간의 인과관계를 분석하기 위해서는 Amos4.0을 이용한 SEM을 실시하였다.
        176.
        2001.10 KCI 등재 서비스 종료(열람 제한)
        옥정호에 대한 수질변화 조사 자료를 토대로 수질모의를 실시하였으며, 그 결과 바탕으로 효율적인 댐저수지 수질관리 방안을 제시하였다. 옥정호의 수질은 계절에 다라 중영양상태와 부영양상태를 나타내는 것으로 평가되었으며 이러한 수질상태는 외부로부터 유입되는 오염원에 많은 영향을 받게 되므로 우선 유역으로부터 유입되는 오염부하의 정확한 산정이 필요한 것으로 평가되었다. 1999년에 조사한 7차례의 강우기간 중 총 부하와 일년간 발생한 총 부하를 비교하면 강우량
        177.
        2001.06 KCI 등재 서비스 종료(열람 제한)
        도시유역의 수자원 개발 및 재해예방을 위해서는 정확한 입력정보의 생성방안을 개발하였고, 급속한 도시화의 영향에 따른 수자원 및 환경문제를 보다 효율적으로 해결하기 위하여 전문가시스템의 개발 및 적용방안을 제안하였다. ARC/INFO를 사용한 지리정보체계의 적용과 인공위성 관측자료를 사용함으로써 넓은 공간에서 시간적 변화가 큰 안양천 유역의 자료들을 합리적으로 획득하였으며, CLIPS 6.0을 적용하여 전문가시스템 ESPE를 개발하였다. 재현결과가 측정자
        178.
        2001.06 KCI 등재 서비스 종료(열람 제한)
        This paper aims to explore effective ways to improve inspection service and develop customer-centered inspection administration, by carrying out a case study on the K Society of Ship Inspection. The methods applied for this research project are as follows, 1) sector-based examination of the existence of the ISO 9001 system; 2) evaluation or the operation or the system; 3) conduction or a survey questionnaire with the participation of all staff and inspections institutes to analyze customer satisfaction of their inspection service, and 4) statistical analysis of the data collected from the survey questionnaire.
        179.
        2001.04 KCI 등재 서비스 종료(열람 제한)
        The Keum river is one of the important river in Korea and has a drainage area of 9,873 ㎦. The Keum river is deepening pollution state due to development of the lower city and construction of a industrial complex. The water quality of the Keum river come to eutrophication state and belong to Ⅲ grade of water quality standard. The concentration BOD in river is affected by the organic loading from a tributary and the algae biomass that largely happen to under eutrophication state. In the eutrophic water mass such as the Keum river, the autochthonous BOD was very important part for making a decision of water quality management, because it was accounted for majority of the total BOD. The purpose of this study was to survey the characteristics of water quality in summer and to estimate reaction coefficient. Also, we studied to correlationship between chlorophyll a and BOD(COD) for estimation of the autochthonous BOD. The correlationship between chlorophyll a and BOD(COD) were obtained through the culture experiment of phytoplankton in the laboratory. The results of this study may be summarized as follows ; The characteristics of water quality in summer were belong to Ⅲ∼Ⅳgrade of water quality standard as BOD and nutritive condition is very high. The BOD, ammonia nitrogen and phosphate loadings in Miho stream which inflowing untreated sewage from Chungju city was occupied with 64.07%, 26.36%, 46.08%, respectively. Maximum nutrient uptake (Vmax) was 0.4400 μM/hr as substrate of ammonia nitrogen, 0.1652 μM/hr as substrate of phosphate. Maximum specific growth rate (μmax) was 1.2525 hr-1 as substrate of ammonia nitrogen, 1.5177 hr-1 as substrate of phosphate. The correlation coefficient between chlorophyll a and BOD by the culture experiment were found to be 0.911∼0.935 and 0.942∼0.947 in the case adding nutrient and no adding nutrient, respectively. The correlation coefficient between chlorophyll a and COD through the culture experiment were found to be 0.918∼0.977 and 0.880∼0.931 in the case adding nutrient and no adding nutrient, respectively. The autochthonous BOD(COD) was estimated to the relationship between BOD(COD) and chlorophyll a. The regression equation were found to be autochthonous BOD=(0.045∼0.073)×chlorophyll a and autochthonous COD=(0.137∼0.182)×chlorophyll a.
        180.
        2001.02 KCI 등재 서비스 종료(열람 제한)
        The Keum river has been utilized for drinking water supply of several city including Kunsan city and is deepening pollution state due to numerous municipal and industrial discharges. The concentration BOD in river is affected by the organic loading from a tributary and the algae biomass that largely happen to under eutrophication state. In the eutrophic water mass such as the Keum river, the autochthonous BOD was very important part for making a decision of water quality management, because it was accounted for majority of the total BOD. The predict of water quality has important meaning for management of water quality pollution of the Keum river. The purpose of this study will manage and predict water quality of the Keum river using QUAL-2E model considering the autochthonous BOD. The estimation of autochthonous BOD represented that the relationship between BOD and chlorophyll a. The regression equation was shown to be autochthonous BOD=β5×chlorophyll a. The results of this study may be summarized as followed; The QUAL-2E model was calibrated with the data surveyed in the field of the study area in June, 1998. The calculated value by QUAL-2E model are in good agree to measured value within relative error of 7.80∼20.33%. Especially, in the case of the considering autochthonous BOD, the calculated value of BOD were fairly good coincided with the observed values within relative error of 15%. But the case of not considering autochthonous BOD, relative error of BOD was shown to be 43.2%. In order to attain Ⅱ grade of water quality standard in Puyo station which has a intake facility of water supply, we reduced to the pollutants loading of tributaries. In the case of removed 100% BOD of tributaries, the BOD of Puyo station was 4.07㎎/ℓ, belong to Ⅲ grade of water quality standard. But in the case of removed 88% nutrient of tributaries, it was satisfied to Ⅱ grade of water quality standard as below 3㎎/ℓof BOD. For estimation of autochthonous BOD in Keum river, we are performed simulating in accordance with reduction of nutrient load(50∼100%) under conditions removal 90% organic load. Occupancy of autochthonous BOD according to nutrient loading reductions were varied from 25.97∼79.51%. Occupancy of autochthonous BOD was shown to be a tendency to increasing in accordance with reduction of nutrient loading. Showing the above results, the nutrient that one of the growing factor of algae was important role in decision of BOD in the Keum river. For the water quality management of the Keum river, therefore, it is necessary to considering autochthonous BOD and to construction of advanced sewage treatment plant for nutrient removal.
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