• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.783-792
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• 2009

This study investigated 31 selected EDCs(Endocrine Disrupting Compounds) and PPCPs(Pharmaceutical and Personal Care Products) in the influent and effluent of a wastewater treatment plant(WWTP) nearby Seoul metropolitan area. The chemical compounds of EDC/PPCPs detected from the plant influent sample include stimulant, X-ray contrast media and fire retardant. The total amount of each compound class were 59.67%, 20.20% and 9.00% respectively. However, in the effluent sample, the major micropolutants detected were oral beta-blocker(30.54%), fire retardant(20.49%), X-ray contrast media(18.17%). The EDC/PPCPs occurrence levels of this study were somewhat lower than previous domestic studies'. When compared to those of overseas, the values were even lower. Some pharmaceutical compound levels particularly measured in European studies were even several thousand times high. This study then compared PECs(Predicted Environmental Concentration) and MECs(Measured Environmental Concentration) of 9 selected pharmaceuticals compounds. The calculated PECs were substantially different with the MECs, while the occurrence order between the PECs and MECs in terms of concentrations of the compounds were similar.

• Journal of the Korean Geosynthetics Society
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• v.17 no.3
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• pp.19-32
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• 2018

Gravel Compaction Pile (GCP) method is currently being designed and constructed by empirical method because quantitative design method has not been developed, leading to various types of and frequent destruction such as expansion failure and shear failure and difficulties in establishing clear cause and developing measure to prevent destruction. In addition, despite the difference with domestic construction equipment and material characteristics, the methods applied to the overseas ground is applied to the domestic as it is, leading to remarkable difference between applied values and measured values in variables such as bearing capacity and the settlement amount. The purpose of this study was, therefore, to propose a reasonable and safe design method of GCP method by analyzing the settlement and stress behavior characteristics according to ground strength change under GCP method applied to domestic clay ground. For the purpose, settlement amount of composite ground, stress concentration ratio, and maximum horizontal displacement and expected location of GCP were analyzed using ABAQUS. The results of analysis showed that the settlement and Settlement reduction rate of composite ground decreased by more than 60% under replacement ratio of 30% or more, that the maximum horizontal displacement of GCP occurred at the depth 2.6 times pile diameter, and that the difference in horizontal displacement is slight under replacement ratio of 30%.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.509-518
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• 2013

Understanding of the exchange between the water and energy which is happening between the surface and atmosphere is the basic of studying water resources. To study these, lots of researches using Noah Land Surface Model(LSM) are in progress. Noah LSM is based on energy and water balance equation and simulates various hydrological factors. There are diverse researches with Noah LSM are ongoing in overseas, on the other hand not enough study has been done. Especially there is almost no study using uncoupled Noah LSM in Korea. In this study we used data from Korea Flux Tower in Haenam(HFK) and Gwangneung(GDK) as forcing data to simulate the model and compared its result of net radiation, sensible heat flux and latent heat flux with the observation data to assess the applicability of Noah LSM in Korea. Regression coefficients of the comparison results of Noah LSM and observation show good agreement with the value of 0.83~0.99 at Haenam and 0.64~0.99 at Gwangneung which means Noah LSM can be trusted.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.37-43
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• 2020

The seismic reinforcement ratio of SOC facilities, such as domestic roads and railroads, is 96%. Out of approximately 7 million buildings as of 2016, only 0.51 million buildings with seismic performance were secured. Although the proportion of masonry structures is 38.8% of the total buildings, there is almost no seismic resistance, only 2.0%. To solve the problem in Korea, government-level seismic measures are being promoted, but the situation is insufficient. Overseas, the UBC research team in Vancouver, Canada, has developed and used EDCC to reinforce the seismic performance of masonry buildings. EDCC is a construction material that can secure concrete ductility capability by mixing fibers and secure deformation resistance of concrete through bridging action. It is necessary to examine various materials because EDCC is not used as a spray type of secure seismic reinforcement. In this study, as part of the research and development of spraying materials to improve the durability of masonry buildings, this study examined the spraying characteristics of fiber-reinforced mortar according to fiber use and the viscosity change according to the use of thickener. As a result, the working performance of the fiber-reinforced mortar for seismic reinforcement was improved when using 1% fiber and 1% thickener.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.167-175
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• 2018

To cope with the increasing number of natural disasters in recent years, managers in the National Disaster and Safety Status Control Center, who have considerable experience and skills, are regarded highly important. Although the National Disaster and Safety Status Control Center oversees the disaster-status control tasks in preparation for various natural and social disasters, there is little data due to the frequent replacement of managers. Therefore, this study developed a disaster-safety code system that tracks and manages disaster information, because the current record management and amount of information sharing remains very low. Among 22 natural and social disaster types, this study targeted four types of disasters: heavy snow, strong winds, high seas, and heavy rain. The final disaster-safety data code system was proposed through the following processes: analysis of the code systems of disaster areas in Korea and overseas, setup of the implementation of directions, development of the classification system, and categorization. For the systematic accumulation of data, the four code systems were integrated into one. A prototype system was developed and operated to verify the validity of the proposed code system. The results showed that data were accumulated and services were provided accordingly with respect to the proposed code system. If past data are accumulated and utilized according to the proposed code system in this study, it will be helpful in the decision making process to respond to new types of disasters, based on past experiences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.432-443
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• 2018

This study aims to present the direction of development of a policy framework to solve the problems associated with Smart Cities. For this purpose, first, after investigating the development process of domestic smart cities, we examined various cases of smart city policies being established overseas. Second, we analyzed the existing research into smart cities, in order to understand the relationship between the major issues. Third, an expert interview was conducted based on the identified issues. Fourth, we presented the direction of development of a Smart City policy framework to solve the major problems associated with domestic and foreign smart cities. In the policy framework presented in this research, after subdividing the elements used for solving each problem, we linked them with the smart city components and selected matching executable agents to prepare solutions. Then, once the deliberation process of the National Smart City Committee and the Smart Urban Service Support Organization has been completed, the government will support it financially and politically. It also suggested that it is necessary to perform continuous information gathering and monitoring work, along with the construction of a control tower to strengthen the network effect between smart city related markets. This research has significance in that it presents the procedures required for efficiently responding to the problems arising in the smart city promotion process. It is expected that it will serve as the basis for establishing policies dealing with the development and advancement of domestic smart cities in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.570-576
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• 2018

In reinforced concrete structures, the joints of ordinary rebars are usually lap joints, which are bound by binding wires with rebars, and mechanical joints by couplers. In domestic design standards (concrete design code), welded lap joints are restricted for ordinary rebars, but overseas standards allow welded lap joints of ordinary rebars through pre-heating. This study investigated the domestic and international standards/criteria and evaluated the fracture strength by performing the tensile test on the lap welded joint of SD400 grade rebars, which is used the most in the construction sites. The weld length of the specimen for weld lap joints is based on the minimum weld length (8d) given in the KS standard (KS B ISO 17660-1). According to AWS D1.4, the preheating temperature was set to $150^{\circ}C$ for D19 and below, and $260^{\circ}C$ for D22 and above. In the test results, the tensile strength of rebars with welded lap joints exceeded the required strength (125% of the yield strength) according to the concrete design code. To analyze the effect of preheating, the tensile strength of the welded rebars after preheating was not significantly different from that of the welded rebars without preheating. The carbon equivalent content (Ceq) of the rebars used in the test was 0.45% or less. Under AWS D1.4, no preheating is required if the carbon equivalent is less than 0.45%. All specimens with a welded lap length of 8d failed by a bar fracture. The effect of preheating was confirmed to be insignificant due to the low carbon equivalent of the rebar.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.354-364
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• 2017

The importance of marine pollution prevention is increasing day by day both at home and overseas. Against this context, this study proposes policy directions to forge an improved system of coastal control for local governments. I have analyzed the coastal pollution response capacity of local governments to find out how the central government can better support these efforts to reinforce capacity. For the purposes of this research, I carried out a number of case studies on large-scale marine pollution accidents that occurred at home and abroad. According to the results, I identified the implications of the coastal pollution response capacity of local governments and suggested several alternatives such as construction of step by step response system, strengthening education and training, part of human network activation, establishment of grounds for securing response resources, and establishment of dedicated department to prepare for potential future marine pollution accidents. However, as little research has been done on the coastal pollution response capacity of local governments, this work may be regarded as an experimental study to help facilitate follow-up research in the future.

• Journal of Korea Port Economic Association
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• v.36 no.3
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• pp.99-114
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• 2020

Overseas advanced ports are promoting smartification, as well as full automation of the terminals surrounding container terminals. A smart port can be defined as a comprehensive concept that pursues increased operational efficiencies, maximization of profit, efficient use of energy, and construction of eco-friendly ports with the introduction of fourth-industrial-revolution technology, including port automation. However, Korea is making efforts to introduce fourth-industrial-revolution technology into ports, but indications are that they are somewhat insufficient compared to advanced ports abroad. Therefore, this study conducted a survey about operators and users of container terminals in Gwangyang Port by deriving the factors determining the introduction of smart ports, such as cost, service, time, safety, and environment, from previous studies. This study analyzed the factors determining the introduction of smart ports and moderating effects when the adjustment variables of operators and users were applied to the pros and cons. As a result of the analysis, it was found that port operators and users have a moderating effect on cost, time, safety, and environmental factors, but not on service factors. These results indicate that port operators try to reduce costs through efficient operation, time management, and by reducing safety accidents by building smart ports, but analysis showed that the negative effects of smart ports have affected port users. The results of this study were derived through a moderated regression analysis and suggested implications for introducing smart ports in the conclusion.

• Journal of Korean Library and Information Science Society
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• v.51 no.1
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• pp.201-225
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• 2020

In order to respond to changes in college's educational goals and talents, university libraries need to be transformed into spaces that support creative and collaborative learning. Apart from overseas cases, it is necessary to discuss the development of creative and collaborative learning spaces appropriate to the situation of Korean university libraries. This purpose of this study is to provide an effective guide to university libraries planning to develop creative and cooperative learning spaces. To this end, this study conducted a literature review to define the concept of a creative and collaborative learning space in a university library, collected and analyzed cases of creative and collaborative learning space of Korean university libraries, and proposed a model for developing creative and collaborative learning space for university library. Case collection was carried out through field visits to 12 university libraries. In addition, in-depth interviews were conducted with the staffs in charge of the construction and operation of five university libraries selected in consideration of the operating entity, region, and scale. This study is meaningful in that it intensively researched and analyzed the advanced cases of creative and collaborative learning spaces in Korea to derive suggestions that can be used in the field of domestic university libraries.