• International conference on construction engineering and project management
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• 2011.02a
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• pp.534-541
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• 2011

Risk evaluation approaches for bidding on international construction projects are typically partitioned into three stages: country selection, project classification, and bid-cost evaluation. However, previous studies are frequently under attack in that they have several crucial limitations: 1) a dearth of studies about country selection risk tailored for the overseas construction market at a corporate level; 2) no consideration of uncertainties for input variable per se; 3) less probabilistic approaches in estimating a range of cost variance; and 4) less inclusion of covariance impacts. This study thus suggests a three-staged risk evaluation model to resolve these inherent problems. In the first stage, a country portfolio model that maximizes the expected construction market growth rate and profit rate while decreasing market uncertainty is formulated using multi-objective genetic analysis. Following this, probabilistic approaches for screening bad projects are suggested through applying various data mining methods such as discriminant logistic regression, neural network, C5.0, and support vector machine. For the last stage, the cost overrun prediction model is simulated for determining a reasonable bid cost, while considering non-parametric distribution, effects of systematic risks, and the firm's specific capability accrued in a given country. Through the three consecutive models, this study verifies that international construction risk can be allocated, reduced, and projected to some degree, thereby contributing to sustaining stable profits and revenues in both the short-term and the long-term perspective.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1991.10a
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• pp.115-120
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• 1991

At the preliminary design stage, the orientations of laminae in a laminate are not known. This fact discourages the most of engineers from the beginning. If the quasi-isotropic constants are used, it halps the design engineer greatly to start his work. If conventional mechanics and elasticity theories can be used, the effort for design and analysis is greatly reduced. This paper reports the possibility of using the classical mechanics at the preliminary design stage for the laminated composite primary structure for civil construction. The result is quite promissing.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.133-138
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• 2003

Axial shortenings of wall and columns were measured on level 2 and precise leveling between wall and columns were surveyed on level 5 at the Galleria Palace structure. Measured and surveyed shortening values were compared with the analysis results at the earlier stage on the process of construction for evaluating the predicted values. Though measured values represent relatively low and scattered values at earlier construction stage, probably they show similar slope curves to predicted ones with the progress of time.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.777-786
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• 2007

This paper presents a modified simulated annealing algorithm to optimize linear scheduling projects with multiple resource constraints and its effectiveness is verified with a proposed problem. A two-stage solution-finding procedure is used to model the problem. Then the simulated annealing and the modified simulated annealing are compared in the same condition. The comparison results and the reasons of improvement by the modified simulated annealing are presented at the end.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.120-125
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• 2003

The estimated construction costs derived at the Planning stage of a project are utilized as important data determining the feasibility of overall project. Therefore the clients usually expect to have estimations of the construction cost as precise as possible and there has been extensive studies carried out by the cost specialists worldwide to satisfy this client's specific need whereas the local estimators still heavily rely on producing quantities and detail quotations only. This paper is to introduce a case study where elemental/functional area cost analysis is incorporated into a database system for the improved accuracy in cost estimations.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.271-272
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• 2018

As the supply and demand of natural aggregate becomes more difficult in the domestic construction site continuously, many studies related to the recycled aggregate produced in the construction waste are going on. However, because of the safety and performance of the recycled aggregate, it is not used as aggregate for the structure, and it is mainly used as a nonstructural material. In addition, as the "recycled aggregate quality standard" has been revised in 2017, quality standards for various properties of recycled aggregate have been adjusted, and production technology suitable for recycled aggregate quality standards for concrete is needed. In this study, to improve the quality of recycled aggregate, we applied multistage wind pressure treatment method to the existing recycled aggregate production facility and compared the density, absorption rate, particle size before and after recycled aggregate treatment. As a result, quality criteria in various properties were analyzed satisfactorily.

• Earthquakes and Structures
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• v.20 no.3
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• pp.309-323
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• 2021

Architectural design decisions and structural systems arrangements affect their earthquake behaviors significantly of reinforced concrete building in Turkey. Because the performances as safe and economical against earthquake loads of reinforced concrete buildings can be provided with especially design decisions in the architectural design stage. This matter reveals the importance of design decisions in the architectural design phase and the right structural system arrangement. The purpose of this study, the short-column situation frequently observed in reinforced concrete buildings after the earthquakes occurred in Turkey are to examine comparatively the effects on behavior and the rough construction cost of the building. The obtained results show that the short column circumstance composed due to different reasons negatively affects the earthquake performance of the reinforced concrete buildings and increases the rough construction cost. This matter shows that the measures to be taken against short column formation should be foreseen especially at the architectural design stage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.244-245
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• 2021

Design VE (Value Engineering) has been basic design and implementation design separately, but due to the recent change in guidelines, it is changing to implement only once in the implementation design stage. However, in the implementation design stage, construction costs, plans, and specifications based on the volume details are almost completed. Therefore, it is effective to perform the function analysis step after identifying information analysis and key issues through CostModeling based on functional center for the selected target in the process of implementing the VE performance procedure.

• Journal of the Society of Disaster Information
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• v.9 no.2
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• pp.195-205
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• 2013

Construction Management means a comprehensive plan of given the resources and the operation of the elements to complete the construction within the construction period. The construction period of these shall be determined by calculation based on reliable initial business. However, in actual field, inaccurate task duration is determined to the intuitive judgments of representative, reference of a similar project construction period of the past. As previous studies for the improvement of existing methods, This study presented a standard model that can be utilized in the early stages of construction projects for the TBM method operating by diameter (2.6m, 3.0m, 3.5m, 5.0m, 8.0m), and This study presented and calculated construction period which can estimated quickly the entire outline the construction period Therefore, When performing TBM construction work in the future, the total construction period which presented and analyze by TBM diameter, can be used as a useful material which plan and manage construction contracts, construction estimating, construction planning to the basic planning stage, and the basic design stage.

• Korean Journal of Construction Engineering and Management
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• v.19 no.4
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• pp.82-92
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• 2018

Considering that earlier stage of construction project has a great influence on the possibility of lowering of environmental load, it is important to build and utilize system that can support effective decision making at the initial stage of the project. In this study, we constructed an environmental load estimation model that can be used at the early stage of the project using basic design factors. The model was constructed by using the artificial neural network to estimate environmental load by applying to planning stage (ANN-1), basic design stage (ANN-2). The result of test, shows that average of absolute measuring efficiency and standard deviation of ANN-1 and ANN-2 were 11.19% / 5.30% and 9.59% / 3.09% each. This result indicates that the model using the input variables extended with the project progress has high reliability and it is considered to be effective in decision support at the initial design stage of the project.