• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.148-158
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• 2013

Generally, building construction projects have a complex decision-making process because of the participation of various agents. In this situation, a final decision is arrived at by relying on subjective judgments based on the experience of project participants. For this reason, a method of assessing the objectivity of opinions is needed. In previous studies, the multi-criteria decision making method was applied to arrive at a final decision objectively, but this method has a limitation, in that the experience of each decision maker is not considered differently in the decision making process. Therefore, this study proposed a theoretical model using the S-shaped growth curve and regression analysis by building construction project type to quantitatively estimate decision-making reliability according to the experience of individual project participant`s. The developed model could be added to the Multi-criteria decision making method, and secure the objectivity and reliability of project participants' final opinion.

• Geomechanics and Engineering
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• v.5 no.6
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• pp.499-517
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• 2013

In order to investigate shear behavior of granular materials due to excavation and associated unloading actions, load-controlled plane strain compression tests under decreasing confining pressure were performed under drained conditions and the results were compared with the conventional plane strain compression tests. Four types of granular material consisting of two quartz sands and two glass beads were used to investigate particle shape effects. It is clarified that macro stress-strain behavior is more easily influenced by stress level and stress path in sands than in glass beads. Development of localized deformation was analyzed using photogrammetry method. It was found that shear bands are generated before peak strength and shear band patterns vary during the whole shearing process. Under the same test condition, shear band thickness in the two sands was smaller than that in one type of glass beads even if the materials have almost the same mean particle size. Shear band thickness also decreased with increase of confining pressure regardless of particle shape or size. Local maximum shear strain inside shear band grew approximately linearly with global axial strain from onset of shear band to the end of softening. The growth rate is found related to shear band thickness. The wider shear band, the relatively lower the growth rate. Finally, observed shear band inclination angles were compared with classical Coulomb and Roscoe solutions and different results were found for sands and glass beads.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.10 no.2
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• pp.1-6
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• 2014

As Korea's economy is entering a period of gradual growth, rate of growth on the construction market is becoming slow like that in developed countries. Remodeling construction market will be gradually expanded due to change in the social environment and diversification of individual demand. This study aims to promote the status of building equipment field with corresponding strategies based on the current situation that the importance of building equipment field is emphasized. Although it is desirable that building equipment construction companies lead remodeling construction, the building equipment part of general construction companies take the important role may be a advisable way, because the technology of building equipment construction companies is a little insufficient. Though building equipment field has become more important, the number of credits and professor of the field is still small than other fields of architectural engineering. More practical curriculums are necessary to meet the expectation of companies. Mechanical part of building equipment construction does not have independent law otherwise the other parts of building equipment construction. Establishing the independent law is urgent to promote the remodeling construction technology.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.190-195
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• 2009

Since the industrial revolution, the global environmental problems such as greenhouse gas accumulation and the average temperature increase have caused people's attention. 'Low Carbon, Green Growth' was presented to cope with these global concerns, as one of main policies of 2008 in Korea. The paradigm of a green urban development is started to concern the whole city's energy problems owing to realize 'Low Carbon, Green Growth' in the urban side. The government established a nation's basic energy plan for 20 years, and some local cities made efforts to develop new renewable energy such as the solar, wind and water energy which are suitable to each city's character. As a part of these efforts, the concept of U-Eco city is newly appeared to reflect upon ubiquitous technique, urban ecology and the next generation energy system. However, urban plan is difficult to adopt this next generation energy system with existing laws, regulations and technical systems. The new executive and systematic system is needed to realize the U-Eco city U-Eco for the management of an efficient city. In this study, the authors investigate the concept of the next generation energy system and U-Eco city to realize the energy-efficient city plan and analyze problems to occur during the application of them in an existing city plan. Then, the authors show the remedies to deal with occurred problems.

• Journal of the Korea Institute of Building Construction
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• v.21 no.6
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• pp.629-640
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• 2021

According to statistics from the Ministry of Land, Infrastructure and Transport in 2018, approximately 37% of residential buildings in Korea need to be reconstructed. Due to the rapid growth of the demolition industry, many side effects such as environmental destruction and safety accidents are becoming a problem in the demolition of existing buildings. This study proposes a decision-making process for selecting the most suitable dismantling method for field application by comprehensively considering safety, economic feasibility, and environmental characteristics. In particular, field applicability is evaluated by evaluating risk factors for the selected method. To this end, this study proposes the TOPSIS method for the selection of the dismantling method using the QFD development concept, and the FMEA method as a continuous development process of the selected method.

• Journal of the Korea Institute of Building Construction
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• v.16 no.3
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• pp.257-269
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• 2016

Joint overseas expansion could contribute domestic large enterprises and small/medium-sized enterprises to expand overseas construction market by complementing each other's vulnerabilities and weaknesses. To invigorate it, not only does mutual effort between both parties matter, but also providing motivation such as institutional incentives and compensations are important for inducing large enterprises to voluntarily expand overseas construction with small/medium-sized enterprises. However, institutional systems exist only to promote win-win growth limited to domestic construction except for overseas construction. Therefore, the purpose of this study is to establish cooperation evaluation system between domestic large enterprises and small/medium-sized enterprises for invigorating joint overseas expansion by evaluating large enterprises cooperation efforts, and offering incentives to some enterprises gaining a good grade. The developed system could contribute to effectively promote win-win growth by providing institutional guidelines. In other words, The government could induce large enterprises cooperation efforts to some parts which small/medium-sized enterprises need, and large enterprises could selectively and intensively support insufficient cooperation part based on the evaluation result.

• Journal of Korean Association for Spatial Structures
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• v.20 no.1
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• pp.61-67
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• 2020

In the era of the Fourth Industrial Revolution, Various attempts are being made to converge new industries with IT industry to find new growth engines in the field of IT, maximizing efficiency in terms of productivity. 3D printers are also related to this, and various studies have been conducted worldwide to utilize them in the construction industry. At present, there is an active effort to study atypical structures using 3D printers. The most widely used method is the use of glass panels, however, the additional cost of the manufacturing process and thus the overall project cost cannot be ignored. In addition, the construction of the curvature of the existing two-way curved surface in the conventional flat joint method is not suitable for implementing an amorphous shape. In this paper, we propose an optimized shape through Abaqus analysis of various shapes of Space Truss interior using 3D printing technology using polymer.

• Journal of architectural history
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• v.16 no.3
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• pp.115-131
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• 2007

Jeong Woo-tae(?-1809) was a military official who had worked as Byeol-Gan-Yeok in the governmental construction works during the late 18th century through the early 19th century. Byel-Gan-Yeok, literally a special technician, was an official post in the governmental construction works that carries specific technical tasks from the mid 18th century. Over 30 years, Jeong Woo-tae had devoted himself in the construction of various royal tombs, city walls, and palace buildings. He showed superb and various techniques in the works of stone carving and architectural details. After finishing the construction of the tomb of King Jeong-jo's father successfully, he was appointed as a governor of a rural town. Being on duty of the governor, he used to participate in the construction works as a technician. He also made a couple of innovative devices in the field of construction, like a carrying apparatus, Byel-Nok-No. His works secured the setting up of the post of Byel-Gan-Yeok in the governmental construction system in the 19th century. But his technical achievement remained as his own private works rather than developing to the universal growth of the craftsmen's skill. This might be a limitation of the Byel-gan-Yeok's role, whose position was remained in the midway between official and craftsman.

• Wind and Structures
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• v.18 no.6
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• pp.599-618
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• 2014

In this study, a square rectangular tall building is considered to investigate the effects of turbulence integral length scale and turbulence intensity on the along-wind responses, across-wind responses and torsional responses of the tall building by Large Eddy Simulation (LES). A recently proposed inflow turbulence generator called the discretizing and synthesizing random flow generation (DSRFG) approach is applied to simulate turbulent flow fields. It has been proved that the approach is able to generate a fluctuating turbulent flow field satisfying any given spectrum, desired turbulence intensity and wind speed profiles. Five profiles of turbulence integral length scale and turbulence intensity are respectively generated for the inflow fields by the DSRFG approach for investigating the effects of turbulence integral length scale and turbulence intensity on the wind-induced responses of the tall building. The computational results indicate that turbulence integral length scale does not have significant effect on the along-wind (displacement, velocity and acceleration) responses, across-wind displacement and velocity responses, while the across-wind acceleration and torsional responses vary without a clear rule with the parameter. On the other hand, the along-wind, across-wind and torsional responses increase with the growth of turbulence intensity.

• Journal of Construction Engineering and Project Management
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• v.1 no.3
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• pp.28-37
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• 2011

Domestic construction companies are suffering from financing difficulties in the wake of the economic slump in Korea and abroad. During this economic slump, real estate investment trusts (REITs), facilitators for improving financing and stimulating construction businesses, have increasingly expanded since their introduction in 2001. However, in terms of growth speed and marketing size, Korean REITs are falling behind those of other nations. The purpose of this study is to suggest a method for composing a portfolio using the Markowitz portfolio selection model to stimulate REITs. The main contents are as follows. First, a comparative analysis was conducted of increased REIT profit with the application of the Markowitz model and the average REIT profit rate from July 3, 2007, to July 21, 2008, during the investment analysis periods. The results showed that the total profit rate from the Markowitz model was about 10% higher than the average REIT profit rate. Second, the sensitivity was analyzed according to the portfolio's data-gathering and replacement cycle to measure the optimum cycle and yield. The six-mouth profit data collection period showed about 16% higher profits with the Markowitz model than with the REITs. The two-week portfolio change period resulted in about 11% higher profits with the Markowitz model than with the REITs.