• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.05a
• /
• pp.11-12
• /
• 2015

Green Frame is a Rahmen structure made of composite precast concrete members. According to the concrete design code, a lower rebar of precast concrete girder, should be extended to the inner precast concrete column. However, such extension of lower rebar may sharply reduce its constructability. To satisfy the criteria, the connection and anchorage of beam rebar should be taken into consideration, yet it is difficult to use lapping as it is not easy to ensure enough space when Green Frame method is adopted. To solve this, a new method of lower rebar connection and anchorage was developed, and this study is intended to review economic feasibility prior to applying the method developed onto sites. The study result can be used as basic data for selection of the optimal joint and anchorage method for lower rebar of the green frame construction.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2003.04a
• /
• pp.161-164
• /
• 2003

Almost all buildings/infrastructures made of composite materials are fabricated without proper design. Unlike airplane or automobile parts, prototype test is impossible. One cannot destroy 10 story buildings or 100-meter long bridges. People try to build 100-story buildings or several thousand meter long bridges. In order to realize "composites in construction", the following subjects must be studied in detail, for his design: Concept optimization, Simple method of analysis, Folded plate theory, Size effects in failure, and Critical frequency. Unlike the design procedure with conventional materials, his design should include material design, selection of manufacturing methods, and quality control methods, in addition to the fabrication method.on method.

• Journal of KIISE:Software and Applications
• /
• v.29 no.8
• /
• pp.595-603
• /
• 2002

Only a few studies have been conducted on how to select multiple classifiers from the pool of available classifiers for showing the good classification performance. Thus, the selection problem if classifiers on how to select or how many to select still remains an important research issue. In this paper, provided that the number of selected classifiers is constrained in advance, a variety of selection criteria are proposed and applied to tile construction of multiple classifier systems, and then these selection criteria will be evaluated by the performance of the constructed multiple classifier systems. All the possible sets of classifiers are trammed by the selection criteria, and some of these sets are selected as the candidates of multiple classifier systems. The multiple classifier system candidates were evaluated by the experiments recognizing unconstrained handwritten numerals obtained both from Concordia university and UCI machine learning repository. Among the selection criteria, particularly the multiple classifier system candidates by the information-theoretic selection criteria based on conditional entropy showed more promising results than those by the other selection criteria.

• International Journal of Advanced Culture Technology
• /
• v.7 no.1
• /
• pp.133-142
• /
• 2019

This study aims to understand how different construction methods impact scenic preference of green wall and clarify features of each construction method to help select the most suitable construction method for the wanted image of a green wall by providing the basic data for further development and distribution of green wall. Questionnaire developed by the Repertory Grid technique proved that 11 adjectives can be used to describe scenic features of a green wall and 4 preference elements. The result of the Scenic evaluation, the Felt type scored high in 'Aesthetic' and 'Maintenance' meaning that it is the most suitable method when constructing a green wall to improve urban scenery. Regression analysis was conducted to understand the link between the preference elements and scenic impression of a green wall. The result is that the higher the preference is on the design of a green wall, the higher the score is for 'Aesthetic'. Also, the higher the preference is on Bio-Diversity, Design, Growth, the higher the score is for 'Natural'. The above findings can be important measures and reference for selection of the right construction method when planning a green wall.

• Journal of the Society of Disaster Information
• /
• v.9 no.2
• /
• pp.164-177
• /
• 2013

From 2010 years to 2013, the selection method of successful bidder has been changed design suitable lowest method, comprehensive evaluation method(bid price adjustment, design score adjustments, weight standards), fixed amount best design method. Therefore this study was presented by analyzing the impact on the domestic construction industry according the way to determine the successful bidder, the evaluation order method and the operational issues through the analysis of order status, order number, results of acceptance an order, success rate range, results of acceptance an order according to weight success rate, results of acceptance an order by work type and order institution of a turnkey alternative tendering construction performed in domestic civil part.

• Journal of the Korea Institute of Building Construction
• /
• v.4 no.2
• /
• pp.119-128
• /
• 2004

Lately construction industry tends to prefer remodeling of existing buildings rather than new construction or reconstruction of buildings due to strengthening of several restriction related to real estates along with prolonged depression. And also, remodeling of building costs less and creates less wastes compared to reconstruction and so it is more profitable in financial and environmental view. However remodeling is process of creating new environment with existing building. Therefor remodeling must follow the procedure realizing problem and fix the problem based on through investigation on existing building and users requirement must be faithfully reflected. Specially in case of apartment houses, since vagueness on ownership and management authority on common parts exists. Hereupon, in this study we are to present the procedure of analyzing apartment house remodeling method through user requirement by approaching to several considerable factors in user request side.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2003.11a
• /
• pp.119-123
• /
• 2003

Lately Construction industry tends to prefer remodeling of existing building rather then new construction or reconstruction of buildings due to strengthening of several restriction related to real estates along with prolonged depression. Specially in case of Apartment houses, since vagueness on ownership and management authority on common part exists. So in this study we are to present the procedure of analyzing apartment house remodeling method through user request by approaching to several considerable factors in user request side.

• International conference on construction engineering and project management
• /
• 2011.02a
• /
• pp.432-438
• /
• 2011

The purpose of the present thesis is to develop bankruptcy prediction models capable of being applied to the Korean construction industry and to deduce an optimal model through comparative evaluation of final developed models. A study population was selected as general contractors in the Korean construction industry. In order to ease the sample securing and reliability of data, it was limited to general contractors receiving external audit from the government. The study samples are divided into a bankrupt company group and a non-bankrupt company group. The bankruptcy, insolvency, declaration of insolvency, workout and corporate reorganization were used as selection criteria of a bankrupt company. A company that is not included in the selection criteria of the bankrupt company group was selected as a non-bankrupt company. Accordingly, the study sample is composed of a total of 112 samples and is composed of 48 bankrupt companies and 64 non-bankrupt companies. A financial ratio was used as early predictors for development of an estimation model. A total of 90 financial ratios were used and were divided into growth, profitability, productivity and added value. The MDA (Multivariate Discriminant Analysis) model and BLRA (Binary Logistic Regression Analysis) model were used for development of bankruptcy prediction models. The MDA model is an analysis method often used in the past bankruptcy prediction literature, and the BLRA is an analysis method capable of avoiding equal variance assumption. The stepwise (MDA) and forward stepwise method (BLRA) were used for selection of predictor variables in case of model construction. Twenty two variables were finally used in MDA and BLRA models according to timing of bankruptcy. The ROC-Curve Analysis and Classification Analysis were used for analysis of prediction performance of estimation models. The correct classification rate of an individual bankruptcy prediction model is as follows: 1) one year ago before the event of bankruptcy (MDA: 83.04%, BLRA: 93.75%); 2) two years ago before the event of bankruptcy (MDA: 77.68%, BLRA: 78.57%); 3) 3 years ago before the event of bankruptcy (MDA: 84.82%, BLRA: 91.96%). The AUC (Area Under Curve) of an individual bankruptcy prediction model is as follows. : 1) one year ago before the event of bankruptcy (MDA: 0.933, BLRA: 0.978); 2) two years ago before the event of bankruptcy (MDA: 0.852, BLRA: 0.875); 3) 3 years ago before the event of bankruptcy (MDA: 0.938, BLRA: 0.975). As a result of the present research, accuracy of the BLRA model is higher than the MDA model and its prediction performance is improved.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.29 no.12
• /
• pp.55-60
• /
• 2015

PG and RG methods are widely known method for calculating the capacity of the emergency generator in construction electrical installation. PG and RG methods are mainly used as a saving a life, fire protection, fire fighting in construction. Because no long distance between the emergency generator and electric motor feeder, the relatively small motor power in construction electrical installation, the capacity of generator in PG and RG methods are little problem of voltage and reactive power of generator. However in many cases the application of the PG and RG method is difficult in the Chemical Plant because it is long distance between the generator and the motor Feeder and motor capacity is very large. Motor starting power factor is about 0.2 lagging power factor and motor starting current is about 6times during motor staring. Also Most of the staring current component is a reactive power component. therefore, it is many cases that lack of reactive power and excess of allowable voltage drop limit and After selection of emergency diesel generator, problems happen during motor starting. Therefore, to be selection of effective emergency generator, active generator power, reactive power and the required reactive power during large motor starting should be considered in chemical plant. It is also required of the verification process through simulation because hand calculation is very difficult considering study cases.

• International Journal of Concrete Structures and Materials
• /
• v.6 no.2
• /
• pp.87-100
• /
• 2012

The process of selecting a repair material is a typical one of multi-criteria decision-making (MCDM) problems. In this study Analytical Hierarch Process was applied to solve this MCDM problem. Many factors affecting a process to select an optimal repair material can be classified into quantitative and qualitative requirements and this study handled only quantitative items. Quantitative requirements in the optimal selection model for repair material were divided into two parts, namely, the required chemical performance and the required physical performance. The former is composed of alkali-resistance, chloride permeability and electrical resistivity. The latter is composed of compressive strength, tensile strength, adhesive strength, drying shrinkage, elasticity and thermal expansion. The result of the study shows that this method is the useful and rational engineering approach in the problem concerning the selection of one out of many candidate repair materials even if this study was limited to repair material only for chloride-deteriorated concrete.