• Journal of Environmental Health Sciences
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• v.10 no.1
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• pp.1-12
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• 1984

The stochastic characteristics of the daily range of water temperature variation was analyzed by employing the techniques of autocorrelation coefficient, autoreggresive model and crosscorrelation model. These time series included daily observations on maximum and minimum values of water temperature and air temperature. The measurement was made by automatic recording instrument at Gu-yee and Dook-do in Han River, and at Waegwan and Gu-mi in Nackdong River in 1981. As a result of this study, it was found that (1) The correlogram of daily water temperature ranges $\Delta AT_i$ and daily air temperature $\Delta AT_i$ at Gu-mi and Gu-yee showed the exponential curves. (2) The most high frequency values of $\Delta AT_i$ and $\Delta WT_i$ were 11$\circ$C and 0.5${\circ}C$ respectively at every measuring site. (3) The correlation coefficients between the daily mean air temperature AT$_i$ and the daily mean water temperature were fairly high as 0.966 at Dook-do and 0.949 at Gu-yee, but the correlation coefficients between $\Delta AT_i$ and $\Delta WT_i$ were very low as 0.1074 at Gu-yee and 0.0324 at Dook-Do.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.3
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• pp.831-840
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• 2016

Hydrodynamic condition can be used to predict particle movement within water column and the results used to optimize environmental conditions for effective site selection, setting of environmental quality standard, waste dispersion, and pathogen transfer. To predict the extent of movement of particle from land, 3D hydrodynamic model that includes particle tracking module was applied to Geoje Bay and to calibrate particle tracking model, floating buoy measurement is operated. The model results show that short time is required for particles released into system from river to be transported to the shellfish farming area. It takes about 2 days for the particles to shellfish farming area under mean flow condition. It meant Geoje Bay, especially shellfish farming area is vulnerable to anthropogenic waste from river.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.25-32
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• 2001

Doosan Construction & Engineering Co., Ltd is building a railway tunnel beneath the Soo-Young River connecting MinLak Station and Centum City Station, a section 230, subway line 2, Pusan City, Korea. When completed the tunnel will have a finished inner diameter of 6.5m(21.311) throughout its total length of 840m(420m = 0.52 miles, Two Single Track Tunnel : 420m＋420m). The ground profile of the face toward shield machine is composed of multi layers, silty clay, clayey gravel, soft rock etc. This research paper is to predict ground deformation and variation of stresses around tunnel using Hyperbolic model, and to reflect the works on the next shield tunneling project. And this research paper is analyzed data of measuring instrument (such as settlement gauge, inclinometer, Multiple extensometer, etc.) which is installed along tunnel line for safety of tunnel. For calculations, the finite difference Method is applied. Backfill grouting material is supposed to have instantly strength of 10kg/$\textrm{cm}^2$ above, although its strength is available after 24 hours passed.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.6
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• pp.3-10
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• 2004

The fundamental study of hydrologic redesign of Donghwa area located in a sccond tributary of Seomjin river was performed. The amounts of hydrologic design were estimated using the available cumulated hydrology data provided by Korea Agricultural and Rural Infrastructure Corporation (KARICO). The management status of The water resources in Donghwa area was also widely surveyed. The probability rainfalls, probable maximum precipitation (PMP) and probability floods were estimated and subsequently their changes analyzed. The amount of 200 year frequency rainfall with l day duration was 351.1 mm, 2.5 % increased from the original design value, and The PMP was 780.2 mm. The concentration time was reestimated as 2.5 hours from existing 2.4 hours. Soil Conservation Service(SCS) method was used to estimate effective rainfall- The runoff curve number was changed from 90 to 78, therefore the maximum potential retention was 71.6 mm, 154 % increased from the original value. The Hood estimates using SCS unit hydrograph showed 8 % increase from original value 623 $m^3$/s to 674 $m^3$/s and The probable maximum Hood was 1,637 $m^3$/s. Although the Row rate at the dam site was increased, the Hood risk at the downstream river was decreased by the Hood control of the Donghwa dam.

• International Journal of High-Rise Buildings
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• v.6 no.1
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• pp.33-47
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• 2017

This mixed-use Raffles City (RCH) development is located near the Qiantang River in Hangzhou, the capital of Zhejiang province, located southwest of Shanghai, China. The project incorporates retail, offices, housing, and hotel facilities and marks the site of a cultural landscape within the Quianjiang New Town Area. The project is composed of two 250-meter-tall twisting towers with a form of vibrant waves, along with a commercial podium and three stories of basement car parking. It reaches a height of 60 stories, presenting views both to and from the Qiantang River and West Lake areas, with a total floor area of almost 400,000 square meters. A composite moment frame plus concrete core structural system was adopted for the tower structures. Concrete filled steel tubular (CFT) columns together with steel reinforced concrete (SRC) beams form the outer moment frame of the towers' structure. The internal slabs and floor beams are of reinforced concrete. This paper presents the engineering design and construction of this highly complex project. Through comprehensive discussion and careful elaboration, some conclusions are reached, which serve as a reference guide for the design and construction of similar free-form, hybrid, mix-use buildings.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.5
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• pp.533-543
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• 2016

Supplying clean and safe water to people is facing both quantitative and qualitative challenges. Due to climate change, access to freshwater becomes increasingly difficult, while pollution from various sources decreases the public trust in water quality. Managed aquifer recharge (MAR) which stores and uses surface water in aquifer is receiving attention as a new technology to secure freshwater. Recently, there is a global expansion in the attempt to combine general purification plants and hazard analysis and critical control point (HACCP) which manages all the process from raw material to consumer for food safety. This research is about an attempt to apply HACCP to the drinking water supply process using MAR to secure both quantity and quality of drinking water. The study site is a MAR plant being constructed in the downstream area of the Nakdong River Basin, South Korea. The incorporation of HACCP with MAR-based water supply system is expected to enhance the safety and reliability of drinking water.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.1
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• pp.89-97
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• 2007

Simple regression models for pollutants load estimation of paddy developed by the Ministry of Environment in 1995 were tested with the data (T-N, T-P, $COD_{Mn}$, and SS) collected from Yeongsan and Seomjin river watersheds, and improvement measures were suggested. Overall, the simulated values showed a great difference from the measured values except for T-P according to the statistical analyses (RMSE, root mean square error; RMAE, root mean absolute error; RB, relative bias; EI, efficiency index). Such difference was assumed due to the fact that the models use only hydrologic factors (quantity factor) associated with precipitation and run-off as input parameters, but do not consider other factors which are likely to affect pollutant concentration (quality factor) including days after fertilization. In addition, in terms of accessibility of the models, some parameters in the models such as run-off depth and run-off amount which can not be obtained from the weather database but should be collected by on-site measurements need to be replaced with other variables.

• Journal of architectural history
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• v.2 no.2 s.4
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• pp.26-36
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• 1993

The ${\ulcorner}$Dae${\lrcorner}$ is a place where a man could commune with nature. Our ancestors, who had very interested in natural landscape, and were named to the typical rock in the nature, which they called 'Dae'. The results of a analyzed the old literature(1530 : early stage of Chosen Danasty) are as follows. 1. The distribution of Dae is differ from provinces. Gangwon-do, Kyongsang-do, Cholla-do had many of the Daes. 2. The characteristics of form were classified into five groups. 1) A type of huge flat rock, which able to sit 5-6 persons(30.2%) 2) A type of mountain peak, which unable to use but seems to use images (27%) 3) A type of cliff(25.4%) 4) A type of fantastic rock (9.5%) 5) A type of stratified rock (6.3%) 3. The behavioral characteristics of the Dae were summarized watching a scenery and strolling (유(遊)), enjoying acenery, and relaxation. 4. The site locations of Dae are various such as, hill top, on cliffs, on the mountain, around river, river side cliff or grand rocks, and so forths.

• Geotechnical Engineering
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• v.4 no.1
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• pp.37-48
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• 1988

This is a part of research projects to investigate the several significant statistical correlati- onships among the various physical and engineering properties of alluvial clayey deposits in the estuary area of the great fixe rivers through the South-West coastal districts where are expected to be developed as large ingustrial site or agricultual development projects. As a first trial, the statistical analyses through computer programs were carried out using the results of laboratory and field tests of 227 soil samples from the Seum-Jin river area. When the initial void ratio which plays crucial role to the settlement of foundation is more than 2.5, the compression indices of soil samples are remarkably scattered, but these indices, which are formulated as a general expression, tend to increase as increasing the clay content, liquid limit, plastic limit and initial void ratio.

• Journal of Ecology and Environment
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• v.30 no.2
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• pp.171-177
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• 2007

Korean rivers and their surrounding environments have been used excessively for rice production in the past and more recently for construction of urban areas to accomodate the rapidly increasing population. Affected Korean rivers experience dramatic fluctuations in their water levels and have faster currents compared with those in other countries. In order to restore more natural conditions in rivers experiencing such conditions, we employed a partial restoration method, which is designed to achieve physical and biological stability simultaneously. Concrete blocks were introduced to increase the river's physical stability during floods, and terra cottem, a soil enhancer, was used to reduce water loss due to intense heat. These interventions increased the river's ability to hold water and thereby promoted plant growth. This restoration method increased vegetation coverage and species diversity in treated areas, and changed the species composition in treated areas to more closely approximate that of the control site. These results suggest that this method is effective in restoring damaged habitats to more natural conditions.