• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.3
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• pp.163-172
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• 1993

A probabilistic approach for evaluation of prediction of the strains using Lade's single surface constitutive model was employed, based on first-order approximate mean and variance. Several experiments such as isotropic compression and drained triaxial compression tests were conducted to examine the variabilities of soil parameters for Lade's model. By taking into account the results of the experimental data such as mean values and standard deviations of soil parameter's, a new probabilistic approach, which explains the uncertainty of computed strains, is applied. The magnitude of the COV for each parameter and the correlation coefficient between the two parameters can be effectively used for reducing the number of the parameters for the model. It is concluded that Lade's single surface constitutive model is surperior model for the prediction of the strain, because the COV of strains is under the "0.51".

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1062-1066
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• 2004

암반 내에 공동을 굴착하여 LPG 혹은 원유를 저장하는 경우 공동에서의 지하수 유입량은 공동상부의 수압과 공동내의 가스압과의 관계를 파악할 수 있는 정량적인 지표가 된다. 공동내의 유입량은 되도록 일정하게 유지되는 것이 굴착등의 시공단계와 공동 운영 및 유지관리면에서 유리하며, 유입량의 급증 혹은 급감이 일어나는 경우는 그 원인을 조기에 규명하여야 한다. 이를 위해서는 지하수위, 가스저장압, 수막공 주입압 등에 따른 공동주변의 유동장 해석, 공동내로의 지하수 유입량 해석을 실시해야 한다. 지하저장공동의 유입량 해석에 있어서는 공동의 정확한 형상을 반영하기 위해서 유한요소법이 보편적으로 사유되어 왔으나 한번 설정한 유한요소망으로부터 공동의 설계요소를 변경하는 작업은 수원하지 않아 설계전단계에서 공동 및 수막 시설의 다양한 배치에 따른 모의를 수행하는데는 다소 무리가 있다. 이러한 불편함은 경계부의 형상과 조건만으로 내부점에서의 미지변수 계산을 효과적으로 수행할 수 있는 경계요소법을 도입함으로써 극복할 수 있다. 따라서 본 연구에서는 지하공동으로 배수되는 유입량 산정을 위해 경계요소법을 근간으로 한 2차원 지하수 흐름모형을 구성하였고, 이를 지하저장공동이 위치한 A기지에 적용하여 상부경계조건인 지하수위의 변화, 수막공 주입압 등에 따른 공동내의 유입량과 공동저장압과의 관계를 정량적으로 분석하였다. 분석 결과를 지하저장공동의 운영 및 유지관리에 활용될 수 있도록 수식화하여 제시하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.620-623
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• 2004

도시하천인 청계천 유역의 물순환 해석을 위한 기초자료로 강우량, 유출량, 상하수도랑, 지하수이용량, 지하수위 변화에 의한 유역 저류량 등의 관측자료를 이용하여 연간 물수지 분석을 수행하였다. 청계천 유역의 물순환 구조는 자연계 유출과 인공계 배수의 구조를 지니고 있으며, 이들의 수문성분을 규명하기 위해서는 각각의 수문성분들의 관측 및 해석이 필요하며, 각 수문성분들의 물수지 분석을 통하여 정량적인 합의 결과를 가시적으로 확보함이 매우 중요하다. 신뢰도와 정확성에 근거한 관측자료를 이용한 물수지 분석은 수문성분들의 총체적 표현이라 할 수 있는 모형(model)의 중요 입력자료이며, 모형의 모의 분석결과를 검증할 수 있는 중요한 기준이 된다. 청계천 유역에 기 설치된 수문모니터링 자료로 물수지 분석을 수행하는 데는 많은 제약과 한계성이 따르므로, 지속적인 수문관측 및 모니터링이 수행된다면 복원 이후 장래의 건전한 물순환 대책 수립에 기여 할 것이다.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.4
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• pp.11-21
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• 2000

This study was aimed to establish different drainage types of soil media on the plant growing in rooftop. For this study, experiment plots were installed on the roof of Social Science building, Chongju University, from April, 1998 to September, 1999. (1) Sand and sandy loam as base and check soils, (2) vermiculite as a inorganic soil media (3) "humus sawdust" and "burned rice hull" as organic soil media were used by various mixing ratio Zoysia japonica, was selected for the experiment. The results of this study are as follows : L5B3S2 and L5H3S2 of bad drainage character with a plastic drainage plate combination caused good growth effect on Zoysia japonica examined in 3 types of drainage layer with 5 types of soil media. From this result, it could be suggested that combined design of plastic drainage plate with 2 soil types - L5B3S2 and L5H3S2 - be desirable composition for regarding weight load and plant growth.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.988-991
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• 2013

In the downstream of the Nakdong River, water facilities - Hapcheon Changyoeng weir, Changyeong Haman weir, Nakdong River left and right sides Barrages - have been built and operated. Each facility is located at a distance. Integrated and linked operation of these water facilities is important for the management of national water resources and efficiency, effectiveness of facilities operations. For the reason, we have planned and made the system that can operate the individual facilities organically, using ICT technologies. At K-water Nakdong River Integrated Operation Water Center near Nakdong River Estuary Barrages in Busan, We implemented the water resource integrated operation system through the ICT systems convergence. For the system we expect significant effects - efficient water management, operating cost saving, etc.

• Geotechnical Engineering
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• v.8 no.2
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• pp.81-96
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• 1992

This paper dealt with the influence of experimental error generated inevitably during performing experiments on the granular soil behaviour analysis selecting Lade's Single Work-Hardening constitutive model. Several isotropic compression-expansion tests and a series of drained conventional triaxial tests with various confining pressures for Baekma river sands were performed and the values of parameters for the above model were determined using computer program developed for this study based on regression analysis. By finding the range of the upper and lower bound for deviator stress and volumetric strain versus axial strain dependant on the increase and decrease of the standard deviation from mean value of parameters, sensitivities of all the parameters were examined. Practical use of program to determine the parameters and capability to predict the behaviour of granular soil by Lade's Single Work -Hardening model verified.

• 한국도로학회지:도로
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• v.10 no.2
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• pp.58-67
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• 2008

교통량이 많은 도심지내 장대 지하차도 건설은 교통정체 해소에 기여를 하지만 초기 공사비가 많이 소요되는 단점이 있다. 또한, 화재등 유고시 이용자의 안전을 최우선으로 고려되어야 한다. 즉, 장대 지하차도 건설에 있어서 경제성과 안전성이 함께 만족할 수 있는 건설 방안이 필요하다. 세종지하차도는 이러한 문제점을 극복하고자 다음과 같이 지하차도의 환기방식 및 단면, 포장형식, 사고 예방 및 발생시를 대비한 종합방재시스템을 구축하였다. $\cdot$환기방식은 종류식 환기방식의 경제성과 횡류식 환기방식의 제연성능을 겸비할 수 있는 조합형 환기방식과 Duct Arch 단면을 적용하여 공사비 절감 및 운영시 유지관리비를 획기적으로 절감하였다. $\cdot$지하차도 포장형식은 화재시 내화성이 우수하며 유독가스 발생이 없는 HPC(고성능 콘크리트 포장) 포장을 적용하여 이용자의 안전을 최우선으로 고려하였고 일반 아스팔트 포장 및 배수성 아스팔트 포장에 비해 우수한 성능과 공용수명을 가진 공법을 적용함으로서 유지보수비용의 절감을 가능하게 하였다. 또한, 콘크리트포장의 단점인 소음발생을 최소화하기 위해 타이닝과 그루빙을 적용하였다. $\cdot$지하차도내 화재 등 유고시 신속한 대피가 가능하도록 피난 연락문 간격을 167m 간격으로 설치하고 비상탈출계단 6개소를 확보하였다. 또한 노약자 및 환자의 지하차도 외부로 대피를 돕기 위해 비상엘리베이터 3개소를 설치하는 등 사고발생 시 종합적으로 대처할 수 있는 시스템을 마련하여 적용하였다.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.3
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• pp.330-337
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• 2005

This study was carried out to propose the managemental improvement of the purification plants and the distribution facilities which can minimize the formation of disinfection by-products in drinking water distribution system. The disinfection by-products were highly created in the water treatment plant that the organic matters were high and the chlorine dosage was excessive. The concentration of DSPs was shown the highest value in August and the lowest value in December, because of temperature and pre-chlorine dosage effect. From the result of tracer test, the travel time from the treatment plant to the end of pipeline was around 3-4 days in summer, 5-6 days in winter, respectively, and the DSPs concentration of the reservoir(end of pipe) was 2-3 times higher than that of the beginning point. The improvement of the chlorination process and structural reformation of distribution facility was demanded to minimize the DSPs increase from purification plant to the end of pipe.

• Korean Journal of Environmental Biology
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• v.35 no.1
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• pp.83-94
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• 2017

Benthic macroinvertebrates were investigated in thermal discharge that flows Buso stream region from December 2015 to February 2016, Korea. Study site was selected for the upstream, downstream relative to the mixing station and mixing station which thermal effluent flows, water quality analysis and benthic macroinvertebrates composition, taxa of EPT-group individuals, analysis of biological water quality. As a result, a total of 4,015 individuals including 50 species, 30 families, 11 orders, 4 classes, and 3 phyla were recognized. Taxa of species is Ephemeroptera 16 species (32.0%) including 6 families, the density composition was highest in 1,848 individuals (46.03%) Diptera. EPT-group occupied during the study period were a total of 1,876 individuals (46.72%) including 32 species and 17 family, lowest in the mixing station for study period. As a results of community analysis, mixing station in the Limnodrilus gotoi and Chironomidae sp.2, which is dominated by the analysis was Ecdyonurus levis, Cincticostella levanidovae, Nemoura KUa. The dominant species showed a difference in the upstream and downstream. In the functional feeding groups, in the upstream and mixing station Gathering-Collectors, downstream it was analyzed that the ratio of the highest Filtering-Collectors and decreased the ratio of Shredders increasing from upstream to downstream. Habitat orientation group is analyzed that accounted for most of the Clingers and Burrowers, from upstream to downstream toward the higher the ratio of Clingers. Biological water quality assessment results were analyzed the worst state in the mixing station with an average 2.73 (${\pm}0.41$). Correspondence analysis, correlation analysis results of water temperature and the cold-water species, as the water temperature increases were analyzed by reducing cold-water species and EPT-group.

• Korean Journal of Ecology and Environment
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• v.45 no.1
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• pp.72-81
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• 2012

We investigated the effects of acid mine drainage (AMD) from abandoned coal mines on benthic macroinvertebrate communities in the upper reaches of the Nakdong River from May to October in 2009. Qualitative and quantitative sampling (Surber sampler: $50{\times}50$ cm; mesh size, 0.2 mm) was conducted at 7 study sites and 3 control sites in the study area. We thus sampled 117 species belonging to 53 families, 15 orders, 6 classes, and 5 phyla; the Ephemeroptera, Plecoptera, and Trichoptera group (EPT-group) represented the majority of the benthic macroinvertebrate community (71 species; 64.5%). In the quantitative sampling, a total of 11,575 individuals belonging to 58 species of benthic maroinvertebrates were sampled from the study sites (Sites 1-7), whereas 2,844 individuals belonging to 79 species were sampled from the control sites (Sites A-C). Tolerant species such as oligochaetes, $Epeorus$ $pellucidus$, $Baetis$ $fuscatus$, Hydropsychidae species, and Chironomidae species were predominant in the study sites. The community indices for the study sites, such as MacNaughton's dominance index (DI) (mean${\pm}$SD, $0.52{\pm}0.21$; range, 0.33-0.85) and the Shannon diversity index ($H^{\prime}$) ($2.06{\pm}0.60$; 1.06-2.57), were different from those for the control sites (DI: $0.29{\pm}0.07$, 0.22-0.35; $H^{\prime}$: $3.13{\pm}0.14$; 3.03-3.30). In the study sites, shredders and scrapers were scarce, whereas gathering-collectors (mainly Chironomidae species) were relatively abundant, as were clingers and burrowers. The detrended correspondence analysis (DCA) and similarity analyses showed that benthic macroinvertebrate communities in the study sites were clearly separated from those of the control sites, with the greatest dissimilarity being noted at the uppermost study site (Site 1), which is located close to an abandoned coal mine. The Korean saprobic index (KSI) and the ecological score using benthic macroinvertebrates (ESB) showed that the uppermost study site (Site 1) was ${\alpha}$-mesosaprobic or heavily polluted, whereas other study sites were in a fair or relatively good condition.