• Title/Summary/Keyword: construction parameters

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A Study on the Characteristics of Parameters in Groundwater Table Fluctuation Model (지하수위 변동 해석모델의 매개변수 특성 연구)

  • Kim, Nam-Won;Kim, Youn-Jung;Chung, Il-Moon
    • Journal of Environmental Science International
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    • v.23 no.4
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    • pp.615-623
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    • 2014
  • The groundwater level varies according to the characteristics and composite materials of aquifer. In this study, specific yield and reaction factor which are the major two hydrogeological parameters in the WTF(Water Table Fluctuation) method were estimated and analyzed spatial characteristics. 8 groundwater level stations which have enough measuring period and high correlation with rainfall in the Hancheon watershed were used. The results showed that specific yield was randomly distributed and reaction factor showed inverse trend with altitude. If the enough data were collected, reaction factor according to altitude in ungauged points could be estimated by using these parameter characteristics.

Seasonal effect on hydrological models parameters and performance

  • Birhanu, Dereje;Kim, Hyeonjun;Jang, Cheolhee;Park, Sanghyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.326-326
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    • 2018
  • The study will assess the seasonal effect of hydrological models on performance and parameters for streamflow simulation. TPHM, GR4J, CAT, and TANK-SM hydrological models will be applied for simulating streamflow in ten small and large watersheds located in South Korea. The readily available hydrometeorological data will be applied as an input to the four hydrological models and the potential evapotranspiration will be computed using the Penman-Monteith equation. The SCE-UA algorithm implemented in PEST will be used to calibrate the models considering similar objective functions bedside the calibration will be renewed to capture the seasonal effects on the model performance and parameters. The seasonal effects on the model performance and parameters will be presented after assessing the four hydrologic models results. The conventional approach and season-based results will be evaluated for each model in the tested watersheds and a conclusion will be made based on the finding of the results.

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Optimization of fairway design parameters: Systematic approach to manoeuvring safety

  • Gucma, Stanislaw;Zalewski, Pawel
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.129-145
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    • 2020
  • The article presents a systematic approach to design of marine navigation channels parameters resulting from manoeuvring and operational safety. Relations between the parameters of waterway system elements and the conditions of safe ship operation have been determined and the objective function of waterway parameters' optimization problems has been minimized with respect to variables of construction and operation costs. These costs have been functionally associated to variables of channel width at the bottom and fairway depth. The method of fairway's width computation at specified safe depth at the preliminary and detailed stages of waterway design has been proposed. The results of this method application have been illustrated with two examples: 1. The modernization of Szczecin-Swinoujscie fairway aimed at accepting vessels of 60,000 DWT capacity. 2. Construction of an approach channel leading to a newly built container terminal in Swinoujscie harbour (Poland), handling ocean-going container ships of 20,000 TEU capacity.

Correlation Between Rheology Parameters and Slump Flow Based on Elapsed Time After Concrete Mixing (콘크리트 비빔 후 경과 시간에 따른 레올로지 정수와 슬럼프 플로의 상관 관계 분석)

  • Lee, Yu-Jeong;Kim, Young-Ki;Han, Dong-Yeop
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.53-54
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    • 2022
  • This study is a basic study to establish the relationship between the conventional fluidity evaluation data of concrete and the rheology parameters. the slump flow and rheology parameters were measured according to the elapsed time after the concrete was mixed. The correlation between the slump flow and the rheology constant was analyzed and the effect of the elapsed time after concrete beating on the correlation between the two data was analyzed.

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MECHANICAL DESIGN APPROACH FOR THE VIRTUAL MOCK-UP STUDY OF BUILDING ENVELOPE DESIGN AND FABRICATION

  • Minjung M.;Yongcheol L.
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.158-162
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    • 2013
  • Building envelope systems with growing complexity in geometry and performance criteria demand adapted workflow processes toward the efficient integration of their design and fabrication. To facilitate integration of the workflow process, this study analyzes relationships among teams who share digital models and exchange information that help project participants identify areas of improvement in task allocation and exchanges among various actors, systems, and activities. In addition, major gaps identified in knowledge transfer, project tracking, and design integration during the performance evaluation stages, emphasize the need for a more comprehensive approach to integrating the design, the fabrication, and the construction parameters of building envelope systems. To evaluate the effectiveness of streamlining interactions of design parameters with fabrication constraints and constructability assessments, this paper examines a mechanical design approach as it applies to various project scenarios to develop a mechanical solution for streamlining building envelope design and construction workflow.

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Determination of Optimum Operating Parameters for Enhanced Alkaline Hydrolysis of Soils Contaminated with TNT (TNT 오염토의 염기성 가수분해 효율 향상을 위한 최적 운전인자 도출)

  • Lee, Hwan;Choi, Jae-Heon;Lee, Cheol-Hyo;Kim, Ju-Yup
    • Journal of Soil and Groundwater Environment
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    • v.20 no.6
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    • pp.103-110
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    • 2015
  • Nitro-aromatic Compounds (NACs) of explosives are structurally non-degradable materials that have an adverse effect to humans and ecosystems in case of emissions in natural due to the strong toxicity. In this study, batch test in the laboratory-scale has been conducted to find some process parameters of alkaline hydrolysis by considering the characteristics of NACs which are unstable in a base status and field application evaluation have been performed on the batch test results. Based on the experimental results of both laboratory and pilot-scale test, the optimum conditions of parameters for the alkaline hydrolysis of soils contaminated with explosives were pH 12.5, above the solid-liquid ratio 1 : 3, above the room temperature and 30 minute reaction time. In these four process parameters, the most important influencing factor was pH, and the condition of above pH 12.0 was necessary for high contaminated soils (more than 60 mg/kg). In the case of above pH 12.5, the efficiency of alkaline hydrolysis was very high regardless of the concentrations of contaminated soils. At pH 11.5, the removal efficiency of TNT was increased from 76.5% to 97.5% when the temperature in reactor was elevated from room temperature to 80℃. This result shows that it is possible to operate the alkaline hydrolysis at even pH 11.5 due to increased reaction rate depending on temperature adjustment. The results found in above experiments will be able to be used in alkaline hydrolysis for process improvement considering the economy.

Smart monitoring analysis system for tunnels in heterogeneous rock mass

  • Kim, Chang-Yong;Hong, Sung-Wan;Bae, Gyu-Jin;Kim, Kwang-Yeom;Schubert, Wulf
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.255-261
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    • 2003
  • Tunnelling in poor and heterogeneous ground is a difficult task. Even with a good geological investigation, uncertainties with respect to the local rock mass structure will remain. Especially for such conditions, a reliable short-term prediction of the conditions ahead and outside the tunnel profile are of paramount importance for the choice of appropriate excavation and support methods. The information contained in the absolute displacement monitoring data allows a comprehensive evaluation of the displacements and the determination of the behaviour and influence of an anisotropic rock mass. Case histories and with numerical simulations show, that changes in the displacement vector orientation can indicate changing rock mass conditions ahead of the tunnel face (Schubert & Budil 1995, Steindorfer & Schubert 1997). Further research has been conducted to quantify the influence of weak zones on stresses and displacements (Grossauer 2001). Sellner (2000) developed software, which allows predicting displacements (GeoFit$\circledR$). The function parameters describe the time and advance dependent deformation of a tunnel. Routinely applying this method at each measuring section allows determining trends of those parameters. It shows, that the trends of parameter sets indicate changes in the stiffness of the rock mass outside the tunnel in a similar way, as the displacement vector orientation does. Three-dimensional Finite Element simulations of different weakness zone properties, thicknesses, and orientations relative to the tunnel axis were carried out and the function parameters evaluated from the results. The results are compared to monitoring results from alpine tunnels in heterogeneous rock. The good qualitative correlation between trends observed on site and numerical results gives hope that by a routine determination of the function parameters during excavation the prediction of rock mass conditions ahead of the tunnel face can be improved. Implementing the rules developed from experience and simulations into the monitoring data evaluation program allows to automatically issuing information on the expected rock mass quality ahead of the tunnel.

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Assessment of tunnel damage potential by ground motion using canonical correlation analysis

  • Chen, Changjian;Geng, Ping;Gu, Wenqi;Lu, Zhikai;Ren, Bainan
    • Earthquakes and Structures
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    • v.23 no.3
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    • pp.259-269
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    • 2022
  • In this study, we introduce a canonical correlation analysis method to accurately assess the tunnel damage potential of ground motion. The proposed method can retain information relating to the initial variables. A total of 100 ground motion records are used as seismic inputs to analyze the dynamic response of three different profiles of tunnels under deep and shallow burial conditions. Nine commonly used ground motion parameters were selected to form the canonical variables of ground motion parameters (GMPCCA). Five structural dynamic response parameters were selected to form canonical variables of structural dynamic response parameters (DRPCCA). Canonical correlation analysis is used to maximize the correlation coefficients between GMPCCA and DRPCCA to obtain multivariate ground motion parameters that can be used to comprehensively assess the tunnel damage potential. The results indicate that the multivariate ground motion parameters used in this study exhibit good stability, making them suitable for evaluating the tunnel damage potential induced by ground motion. Among the nine selected ground motion parameters, peck ground acceleration (PGA), peck ground velocity (PGV), root-mean-square acceleration (RMSA), and spectral acceleration (Sa) have the highest contribution rates to GMPCCA and DRPCCA and the highest importance in assessing the tunnel damage potential. In contrast to univariate ground motion parameters, multivariate ground motion parameters exhibit a higher correlation with tunnel dynamic response parameters and enable accurate assessment of tunnel damage potential.

Parametrized Construction of Virtual Drivers' Reach Motion to Seat Belt (매개변수로 제어가능한 운전자의 안전벨트 뻗침 모션 생성)

  • Seo, Hye-Won;Cordier, Frederic;Choi, Woo-Jin;Choi, Hyung-Yun
    • Korean Journal of Computational Design and Engineering
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    • v.16 no.4
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    • pp.249-259
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    • 2011
  • In this paper we present our work on the parameterized construction of virtual drivers' reach motion to seat belt, by using motion capture data. A user can generate a new reach motion by controlling a number of parameters. We approach the problem by using multiple sets of example reach motions and learning the relation between the labeling parameters and the motion data. The work is composed of three tasks. First, we construct a motion database using multiple sets of labeled motion clips obtained by using a motion capture device. This involves removing the redundancy of each motion clip by using PCA (Principal Component Analysis), and establishing temporal correspondence among different motion clips by automatic segmentation and piecewise time warping of each clip. Next, we compute motion blending functions by learning the relation between labeling parameters (age, hip base point (HBP), and height) and the motion parameters as represented by a set of PC coefficients. During runtime, on-line motion synthesis is accomplished by evaluating the motion blending function from the user-supplied control parameters.

Shoreline Changes due to the Construction of Offshore Structure and its Numerical Calculation (이안 구조물 건설에 따른 해안선의 변화와 수치계산)

  • 신승호
    • Journal of Korean Port Research
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    • v.15 no.1
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    • pp.47-56
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    • 2001
  • A numerical model for practical use based on the 1-line theory is presented to simulate shoreline changes due to construction of offshore structures. The shoreline change model calculates the longshore sediment transport rate using breaking waves. Before the shoreline change model execution, a wave model, adopting the modified Boussinesq equation including the breaking parameters and bottom friction term, was used to provide the longshore distribution of the breaking waves. The contents of present model are outlined first. Then to examine the characteristics of this model, the effects of the parameters contained in this model are clarified through the calculations of shoreline changes for simple cases. Finally, as the guides for practical application of this model, several comments are made on the parameters used in the model, such as transport parameter, average beach slope, breaking height variation alongshore, depth of closure, etc. with the presentation of typical examples of 3-dimensional movable bed experimental results for application of this model. Here, beach change behind the offshore structures is represented by the movement of the shoreline position. Analysis gives that the transport parameters should be taken as site specific parameters in terms of time scale for the shoreline change and adjusted to achieve the best agreement between the calculated and the observed near the structures.

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