• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.3-9
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• 2016

This study proposes a approximate cost estimation system based on Excel with VBA using weighted CBR(Case Based Reasoning). One characteristic of this system is that it generates the sheet automatically as many as the number of similar case and new estimation when it performs a case learning and a new estimate and cell formula is automatically entered into each sheet. User can be free to compose a combination of attribute factors because they can select up to ten attribute factors. This paper presents an applicability of estimation model for estimating the soil remediation cost when it use a landfarming method. When compared to a estimation model by using average unit cost and optimum multiple regression, this model shows a better result. This study was aimed at landfarming method, but it is expected that a cost estimation model using CBR will be more likely to apply in soil remediation technologies which various remediation technologies and pollutant species exist.

• Journal of the Korea Institute of Building Construction
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• v.11 no.5
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• pp.523-529
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• 2011

In a tall building construction with reinforced concrete structures, the selection of an appropriate formwork system is a crucial factor for the success of the project. Thus, selecting an appropriate formwork system affects the entire construction duration and cost, as well as subsequent construction activities. However, in practice, the selection of an appropriate formwork system has depended mainly on the intuitive and subjective opinion of working level employees with restricted experience. Therefore, in this study, a formwork system selection model using the Adaboost algorithm is proposed to support the selection of a formwork system that is suitable for the construction site conditions. To validate the applicability of the proposed model, the selection models Adaboost and ANN were both applied to actual case data of tall building construction in Korea. The Adaboost model showed slightly better accuracy than that of the ANN model. The Adaboost model can assist engineers to determine the appropriate formwork system at the inception of future projects.

• Journal of Engineering Education Research
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• v.22 no.5
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• pp.13-19
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• 2019

It is important to encourage students who are having difficulty learning mathematics and majors due to lack of basic knowledge, and encourage them to improve their academic performance by focusing on and participating in class. The purpose of this study is to confirm the applicability of the Jigsaw Method by analyzing the change of the learner's academic achievement and the attitude of the learner's mathematics by applying the Jigsaw Model. During the four weeks, the Jigsaw Model was applied to 30 experimental students and the instructor-led lectures were given to 36 students in the comparative group. As a result of the study, it was confirmed that the average of the experimental groups applying the Jigsaw model was higher than the average of the comparative group in the lecture class. The results of the survey showed that the Jigsaw Model increased class concentration and participation, helped self - directed learning, and had high learning satisfaction.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.1
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• pp.9-19
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• 1998

A laboratory study was conducted to investigate the immobilization of the laboratory waste sludge, mainly from chemical oxygen demand (COD) waste, using cementitious binders. The binders were: Ordinary Portland Cement (OPC), and lime-Rice Husk Ash(RHA) cement. The economic evaluation was done for three different kinds of cementitious binders, namely, OPC, Portalnd Rice Husk Ash Cement (PRHAC) which contained rice husk ash 50 percent by dry weight, and lime-RHA cement. The result showed that lime-RHA cement was the cheapest. The applicability of Freundlich's desorption isotherm was studied to assess the teachability of sludges. The teachability of cement mortars was found to follow the desorption isotherms. Therefore, it was concluded that based on this test, the leachate concentrations of the solidified heavy metals could be predicted, approximately by the Freundlich's isotherm desorption modeling.

• Journal of Environmental Science International
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• v.2 no.1
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• pp.9.2-19
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• 1993

A laboratory study was conducted to investigate the immobilization of the laboratory waste sludge, mainly from chemical oxygen demand (COD) waste, using cementitious binders. The binders were: Ordinary Portland Cement (OPC), and lime-Rice Husk Ash (RHA) cement. The economic evaluation was done for three different kinds of cementitious binders, namely, OPC, Portaind Rice Husk Ash Cement (PRHAC) which contained rice husk ash U percent by dry weight, and lime-RHA cement. The result showed that lime-RHA cement was the cheapest. The applicability of Freundlich's desorption isotherm was studied to assess the teachability of sludges. The teachability of cement mortars was found to follow the desorption isotherms. Therefore, it was concluded that based on this test, the leachate concentrations of the solidified heavy metals could be predicted, approximately by the Freundlich's isotherm desorption modeling.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.75-82
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• 2002

Shaking table model tests are performed to reproduce the dynamic behavior of a gravity quay wall and a pile-supported wharf damaged by Kobe earthquake in 1995. Using the scaling relations suggested by Scott and Iai(1989), the results of the model tests are compared with field measurements as well as with those of the model tests previously executed. The displacements of the gravity quay wall predicted by the current model tests are, at most, one third of the measured displacements, while the displacements of the model pile-supported wharf are about two thirds of the measured values. One possibility for the discrepancy is speculated to be the use of too big scaling factor, i.e., too small size of model.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.2
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• pp.37-43
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• 1999

This study was conducted to develop the simple and convenient irrigation control model which can maintain the appropriate rates of irrigation and drainage of nutrient solution according to the enviornmental conditions and growth stages in soilless culture of cucumber. In order to obtain fundamental data for development of the model, investigation of the actual state of soilless culture practices was carried out. Most irrigatioin systems of soillness culture were controlled by the time colock. Evapotranspiration of cucumber in soilness culture was investigated and correlations with environmental conditions were analyzed , and its estimating model was developed. In order to develop the irrigation system which can control the amount of nutrient solution applied according to seasons, weather conditions, and growth stages, a irrigation clock control was developed. Applicability of the model was tested by simulation. Drainage rates of nutrient solution controlled by conventional time clock, integrated solar radiation, and the developed model were 61% , 20%, and 32% , respectively in cucumber perlite culture.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.2
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• pp.148-158
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• 1998

The aims of this study are to evaluate the application on the stress-strain behavior of granite Soil using Lade's double work hardening constitutive model based on the theories of elasticity and plasticity. From two different sites of construction work, two disturbed and compacted weathered granite samples which are different in partical size and degree of weathering respectively were obtained. The specimen employed were sampled at Iksan and Pochon in order to predict the constitutive model. Using the computer program based on the regression analysis, 11 soil parameters for the model were determined from the simple tests such as an isotropic compression-expansion test and a series of drained conventional triaxial tests. In conclusion, it is shown that Lade's double work hardening model gives the good applicability for processing of stress-strain, work-hardening, work-softening and soil dilatancy. Therefore, this model in its present form is applicable to the compacted decomposed granite soil.

• Journal of applied mathematics & informatics
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• v.29 no.3_4
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• pp.781-802
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• 2011

Of concern in the paper is a Holling-Tanner predator-prey model with modified version of the Leslie-Gower functional response. Dynamical behaviours such as stability, permanence and Hopf bifurcation have been carried out deterministically. Using the normal form theory and center manifold theorem, the explicit formulae determining the stability and direction of Hopf bifurcation have been derived. The deterministic model is extended to a stochastic one by perturbing the growth equation of prey and predator by white and colored noises and finally the mean square stability of the stochastic model systems is investigated analytically. An extensive quantitative analysis has been performed based on numerical computation so as to validate the applicability of the proposed mathematical model.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.761-766
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• 1998

GPR(Ground Penetrating Radar) designed with a digital-based signal processing technology utilizes to identify very easily the location, the thickness and the level of either an underground embedment or an underground structure. Prior to use of this GPR equipment on pavement of about 15cm thick, the equipment should foremost be calibrated on a known sample under known condition. The purpose of this study is to verify the applicability of the GPR equipment to a model pavement of about 15cm thick. As part of this effort, the general approach of this study is to verify the applicability of the GPR equipment by various thickness levels and its error ranges thru a statistical analysis.