• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.191-197
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• 2018

With a population of more than 10 million people worldwide, MegaCity was only three in 1975, but it is expected to grow to 24 in 2013 and more than 30 in 2025 and more than 3 billion worldwide by 2050 It is expected to be absorbed into smart city. Especially in Asia and Africa, urbanization is expected to proceed rapidly. As the urbanization progresses and the population living in the cities increases, there are various problems such as rapid increase of energy consumption, congestion of traffic, various aging of the infrastructure and the like. As a result, smart city is emerging as a new alternative for solving urban problems. Smart City is rapidly expanding with the development of related technologies and can improve costs, improve urban services, improve quality of life, productivity and sustainability. Therefore, this paper analyzes the size and trend of the domestic and overseas smart city market, and analyzes the smart city related policies, trends and case studies of major countries to see the development status and market of smart city related industries, Present a business utilization model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.2
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• pp.307-315
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• 2016

Many countries are trying to reduce a greenhouse gas to step up their fight against climate change. There are many studies related to building only for reducing a greenhouse gas in construction area but studies related to reducing a comprehensive environmental load including various pollutants that affects the global environment are lacking. This study aims to analyse the characteristics of environmental load by work type for tunnel projects. Analysis showed that seven work types, including lining concrete, shotcrete, tunnel portal and open-cut tunnel work, etc., are representative works generated environmental load. These seven works represent 89.22 percent of total environmental load. In addition, comparison results of environmental load per tunnel's length by work type showed that a major factor of environmental load is caused by a tunnel portal and open-cut tunnel work with relatively short length (excavation length). And lining concrete and shotcrete work are larger than any other environmental load with tunnel's total length. It is expected that the result of this study will be used to make a estimation model for environmental load using approximate quantity survey of representative work types in the early stage of tunnel design. And it will be play a considerable role in establishing of environment management plan for sustainable infrastructure construction.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1173-1180
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• 2013

The construction industry has been a major player in Korean economy growth and it has been accountable for more than 15% of GDP during the last decade. However, fast-growing construction industry has also produced some unpleasant side-effects. Environmental problems are identified one of the main issues in the Korean construction industry and they are closely related to minimizing the carbon emission and delivering environmental-friendly green products. The movement of green construction, now, is considered the next driving force for the industry which has significant impacts on the future. This research investigates this green construction while focusing on governmental policy implications such as green certificate for construction products. Green building has long been recognized as the leading green construction product and the green trends have expanded to infrastructure construction such as road construction. Therefore, this research concentrates on various green road certification processes in the United States in order to develop a framework for Korean green road certification. In doing so, some of the green roads application has also been analyzed. This research intends to provide background information for Korean green construction policies, especially on green road certification.

• Steel and Composite Structures
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• v.36 no.5
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• pp.553-568
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• 2020

Steel-concrete composite structures have been extensively used in building, bridges, and other civil engineering infrastructure. Shear stud connectors between steel and concrete are essential in composite members to guarantee the effectiveness of their behavior in terms of strength and deformability. This study focuses on investigating the shear stiffness of headed studs embedded in several types of concrete with wide range of compressive strength, and their effects on the elastic behavior of steel-concrete composite girders were evaluated. Firstly, totally 206 monotonic push-out tests from the literature were reviewed to investigate the shear stiffness of headed studs embedded in various types of concrete (NC, HPC, UHPC etc.). Shear stiffness of studs is defined as the secant stiffness of the load-slip curve at 0.5V_u, and a formulation for predicting defined shear stiffness in elastic state was proposed, indicating that the stud diameter and the elastic modulus of steel and concrete are the main factors. And the shear stiffness predicted by the new formula agree well with test results for studs with a diameter ranging from 10 to 30 mm in the concrete with compressive strength ranging from 22.0 to 200.0MPa. Then, the effects of shear stiffness on the elastic behaviors of composite girders with different sizes and under different loading conditions were analyzed, the equations for calculating the stress and deformation of simply supported composite girders considering the influence of connection's shear stiffness were derived under different loading conditions using classical linear partial-interaction theory. As the increasing of shear stiffness, the stress and deflection at the most unfavorable section under partial connected condition tend to be those under full connected condition, but the approaching speed decreases gradually. Finally, the connector's shear stiffness was recommended for fully connection in composite girders with different dimensions under different loading conditions. The findings from present study may provide a reference for the prediction of shear stiffness for headed studs and the elastic design of steel-concrete composite girder.

• Journal of the Korean Applied Science and Technology
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• v.25 no.4
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• pp.539-555
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• 2008

It is well understood that developing new drugs is one of the highest value-added businesses in a country; however, the current governments' spending in pharmaceutical research and development(R&D) is minimal in Korea. This paper suggests that different governmental bodies should take in charge of different stages of the R&D process in order to maximize the use of limited government research funding. First, during the initial phase of the drug development, including clinical trials, the Ministry of Education, Science and Technology is the most appropriate governmental organization to support the research. For later procedures such as supporting the industries for exporting developed drugs, legislative approvals, and building infrastructure for future clinical trials should be supported by the Ministry of Knowledge and Economy and the Ministry of Health and Welfare along with the Korea Food and Drug Administration(KFDA). The KFDA, which is the main governmental agency approving newly developed drugs in the market, will need to take a crucial responsibility in the initial phase of the pharmaceutical R&D by guiding the industries with timely and proper information. As a first step, it is recommended to set up and operate a center for supporting new drugs, so that the industries can facilitate the development of marketable drugs which meet customers' needs. Later, in order to expedite the process of exporting and getting approvals of the newly developed drugs from foreign countries, it is necessary to develop new approval system, which includes introduction of the Good Manufacturing Practice (GMP), mandatory validation system, and education program for supporting expertise. Lastly, the KFDA needs to take an active role in developing Korean pharmaceutical industries by communicating with other foreign governments with regards to the globalization of the Korean pharmaceutical industries. For example, as a follow up after the Free Trade Agreement(FTA), active discussion on GLP of Mutual Recognition Agreement(MRA) with the United States of America, should be seriously considered.

• Journal of Korea Water Resources Association
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• v.49 no.5
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• pp.399-410
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• 2016

In case of the application of Hazen-Williams C for design, operation or maintenance of water supply system, field situations always should be reflected on the factors. In this study, the relationships between C factors and influencing factors are analyzed using statistical techniques with 174 measured C factor data collected in periodic inspection for safety diagnosis in multi-regional water supply systems. To analyze their relationships, cross analysis, one-way ANOVA, correlation analysis were conducted. Analysis results showed that C factors had high correlations with both of elapsed year and pipe diameter and were relatively highly affected by coating material among influencing factors with the categorical type. On the other hand, elapsed year, pipe diameter and water type were meaningful influencing factors according to the results of multiple regression analysis. The Cluster analysis revealed that C factors had a tendency of being fundamentally classified on the basis of the elapsed year of about 20 years and the pipe diameter of 1500mm. Although C factors were generally greatly affected by elapsed year, size of pipe diameter relatively had an large influence on values of them in case of large diameter pipes. Lastly, It can be suggested that C factor estimation formulas using multiple regression analysis and clustering analysis in this study, can be applied as decision standards of C factor in multi-regional water supply systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.147-156
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• 2016

This study analyzed the impact of changes in the construction business on construction company insolvency according to their size using the vector error correction model. First, this study applied EDF (Expected Default Frequency), which was calculated by KMV (Kealhofer, McQuown and Vasicek) model, as a variable to indicate the insolvency of construction companies. This study set 30 construction companies listed to KOSPI/KOSDAQ for estimating the EDF by size and construction companies were divided into two groups according to their size. To examine the construction business cycles, the amount of construction orders according to the type-residential, non-residential, and civil work- was used as a variable. The serial data was retrieved from TS2000 established by the Korea Listed Companies Association (KLCA), Statistics Korea. The analysis period was between the second quarter of 2001 and fourth quarter of 2015. As a result of calculating the EDF of construction companies by size, as it is generally known, the large-sized construction companies showed lower levels of insolvency than relatively smaller-sized construction companies. On the other hand, impulse response analysis based on VECM confirmed that the level of insolvency of large-scaled companies is more sensitive to business fluctuations than relatively smaller-sized construction companies, particularly changes in the residential construction market. Hence it is a major factor affecting the changes in insolvency of large-sized construction companies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.481-487
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• 2020

This study examined the behavior change of river levees during an earthquake by numerical analysis. Unlike conventional research using artificial earthquake waves, earthquake analysis was performed using real earthquake waves. The behavior of a river levee before and after an earthquake was compared and analyzed quantitatively. Studies show that the river levee has a safety factor of approximately 28.5% due to an earthquake. On the other hand, the minimum standard safety factor is satisfied. Vertical effective stress has decreased by 81.8% due to excess pore-water pressure generated by the earthquake. In addition, liquefaction occurs in most of the foundation soil. An examination of the stress-displacement behavior due to the earthquake revealed a large amount of settlement in the backfill layer. Most of the foundation soil yielded. Therefore, the target river levee is quite vulnerable to earthquakes. Through the results of this study, the necessity of refreshing the seismic design standards for river levees is required. This study can be used as basic data for estimating the approximate damage level and vulnerable areas.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.73-81
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• 2020

This study demonstrated the effect of IT Ssupports for Iintegration Ccompetency(ITSIC) on organizational performance by using organizational temperance and absorption capacity as medium. The research model was verified with Smart PLS 3.0 based on the survey conducted overa total a total of of 126 pparticipantseople's surveys for the employees. First, the ITSIC had a positive effect on both the alignment and adaptability and also on absorption capacity. Second, it was confirmed that organizational temperance hads a positive effect on absorption capacity. Third, when the organizational temperance was mediated in the relationship between ITSIC and absorption capacity, it had a indicated a positive effect. Fourth, absorption capacity had a positive impact on organizational performance. The implications of this study differ from the existing studies through by validating validation of correlations correlations by extending IT technology and organizational performance to organizational ethical factors. In addition, it has been established that the ethical factors of the organization also act as leading factors of absorption capacity. ITSIC helps managers make balanced decision-making, which can contribute to improving absorption capacity by giving members a positive perception, ultimately having a positive impact on organizational performance. It suggests the importance of building appropriate IT infrastructure and cultivating organizational virtues in order to improve the performance of organizations in which absorption capacity is essential.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.33-40
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• 2020

Various studies have been conducted on the structural health monitoring using optical fiber. Optical fibers can be used to measure multiple and distributed strain. Among the optical fiber sensors, FBG sensor has advantages of dynamic response measurement and high precision, but the number of measurement points is limited. Distributed fiber sensors, represented by distributed Brillouin sensors, usually have more than 1000 measurement points, but the low sampling rate makes dynamic measurements impossible. In this study, a hybrid nerve sensor system using only the advantages of the FBG sensor and the distributed Brillouin sensor has been proposed. Laboratory experiments were performed to verify the proposed system, and the accuracy and reproducibility were verified by comparing with commercial sensors. Applying the proposed system, dynamic response ambient measurements are used to evaluate the global state of the structure. When an abnormal condition is detected, the local condition of the structure is evaluated by static response measurement using the distributed measurement system. The proposed system can be used for efficient structural health monitoring.