• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.161-163
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• 2021

This urban centralization is expected to develop rapidly, with 75% of the population living in the city by 2035. Large cities are becoming unsustainable due to side effects such as environmental pollution, severe traffic jams, excessive energy depletion, and destruction of the natural ecosystem. In addition, the happiness index of citizens of large cities is also falling because of high crime rates and safety accidents, the work-life imbalance caused by inequality and polarization, and overly competitive education. To solve this problem, Smart City, an IT-based future city model, was born. The Korean government is also actively attempting to improve urban competitiveness and promote sustainable development through efficient construction and operation of smart cities as a national focus project. To support the effort, we review the basic directions and strategies of Sejong City's Smart City service infrastructure based on the comprehensive national land plan, Smart City plan, and Smart City strategy plan.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.150-152
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• 2021

For the development of a resource recycling society, it is important to control the generation of waste in all processes such as production, distribution, consumption and disposal, and to recycle the recyclable resources of waste instead of simply landfilling and incineration. However, in order to develop a resource-recycling society, not only emitters, businesses, and the central government, but also local governments need to work together to find a solution. Therefore, in this study, we present a promotion strategy for the development of Sejong City's resource-recycling society, taking into consideration the current situation of Sejong City as well as changes in the government's institution system. We suggest that regionally preparing recycling priority management plan, maximizing waste resource utilization, establishing recycling industry activation plan, and building a systematic and efficient recycling platform, etc.

• Convergence Security Journal
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• v.22 no.2
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• pp.27-42
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• 2022

In the era of the Fourth Industrial Revolution, digital transformation to increase the effectiveness of industry is becoming more important to achieving the goal of industrial innovation. The digital new deal and smart defense are required for digital transformation and utilize artificial intelligence, big data analysis technology, and the Internet of Things. These changes can innovate the industrial fields of national defense, society, and health with new intelligent services by continuously expanding cyberspace. As a result, work productivity, efficiency, convenience, and industrial safety will be strengthened. However, the threat of cyber-attack will also continue to increase due to expansion of the new domain of digital transformation. This paper presents the risk scenarios of cyber-attack threats in the Fourth Industrial Revolution. Further, we propose a preemptive intrusion response model to bolster the complex security environment of the future, which is one of the fundamental alternatives to solving problems relating to cyber-attack. The proposed model can be used as prior research on cyber security strategy and technology development for preemptive response to cyber threats in the future society.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2578-2590
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• 2023

In this work, a 24-month two-batch fuel management strategy for the APR1400 using LEU + has been investigated, where enrichments of 5.9 and 5.2 w/o are utilized in lieu of the conventional 4-5 w/o UO₂ fuel. In addition, an Accident Tolerant Fuel (ATF) clad based on the swaging technology is applied to APR1400 fuel assemblies. In this special ATF clad design, both outer and inner SS316 layers protect the conventional zircaloy clad. Erbia (Er₂O₃) is introduced as a burnable absorber with two-fold goals to lower the critical boron concentration in the long-cycle LEU + loaded core as well as to handle the LEU + fuel in the existing front-end fuel facilities without renewing the license. Two types of fuel assemblies with different loading of gadolinia (Gd₂O₃) are considered to control both the reactivity and the core radial power distribution. The erbia burnable absorber is uniformly admixed with UO₂ in all fuel pins except for the gadolinia-bearing ones. In this study, two core designs were devised with different erbia loading, and core performance and safety parameters were evaluated for each case in comparison with a core design without any burnable absorbers. The core analysis was done using the two-step method. First, cross-sections are generated by the SERPENT 2 Monte Carlo code, and the 3-D neutronic analysis is performed with an in-house multi-physics nodal code KANT.

• Structural Engineering and Mechanics
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• v.85 no.4
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• pp.531-543
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• 2023

The existing concrete bridges are time-varying working systems, where the maintenance strategy should be planned according to the time-varying performance of the bridge. This work proposes a time-dependent residual capacity assessment procedure, which considers the non-stationary bridge load effects under growing traffic and non-stationary structural deterioration owing to material degradations. Lifetime bridge load effects under traffic growth are predicated by the non-stationary peaks-over-threshold (POT) method using time-dependent generalized Pareto distribution (GPD) models. The non-stationary structural resistance owing to material degradation is modeled by incorporating the Gamma deterioration process and field inspection data. A three-span continuous box-girder bridge is illustrated as an example to demonstrate the application of the proposed procedure, and the time-varying reliability indexes of the bridge girder are calculated. The accuracy of the proposed non-stationary POT method is verified through numerical examples, where the shape parameter of the time-varying GPD model is constant but the threshold and scale parameters are polynomial functions increasing with time. The case study illustrates that the residual flexural capacities show a degradation trend from a slow decrease to an accelerated decrease under traffic growth and material degradation. The reliability index for the mid-span cross-section reduces from 4.91 to 4.55 after being in service for 100 years, and the value is from 4.96 to 4.75 for the mid-support cross-section. The studied bridge shows no safety risk under traffic growth and structural deterioration owing to its high design safety reserve. However, applying the proposed numerical approach to analyze the degradation of residual bearing capacity for bridge structures with low safety reserves is of great significance for management and maintenance.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.146-152
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• 2017

Recently, countries in the South-east Asia are making efforts to enhance the construction industry system and introduce the construction management system. However, it is challenging to apply construction management in site due to lack of technology and professionals for CM. This can result in frequent safety accidents, cost overrun, schedule delay, etc. Therefore, it is necessary to carry out a clear evaluation of the overall situation regarding the level of technology and required competency. The objective of this research is to investigate on which management skills and items for CM are required to improve the construction management skills in South-east Asian construction industry. As a result of the questionnaire, most of the officials selected that the design phase and the construction phase are important works, and the engineers evaluated activities during the bidding phase, the design phase and the construction phase as important works for construction management. However, in most of the results, it was observed that the current competency of Vietnam construction is insufficient compared to the evaluated importance of the skills. This can be explained by the fact that they are not capable of managing construction projects effectively as compared to the importance. The results can help to realize the inadequate aspects of local construction industry, which will be the basis of improvements. Also, it is expected to be supportive to improve construction management in the countries and also provide indicators related to work stage or technology that should be acknowledged when establishing the advancing strategy for Southeast Asian countries in the future.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.390-390
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• 2013

Use of recycled aggregates in portland cement concrete construction can offer benefits associated with both economy and sustainability. Testing performed to date indicates that RBMA can be used as a 100% replacement for conventional coarse aggregate in concrete that exhibits acceptable mechanical properties for use in structural and pavement elements, including satisfactory performance in some durability tests. RBMAC is currently not used in any type of construction in the United States. However, use of RBMAC could become a viable construction strategy as sustainable building practices become the norm. Rating systems such as LEED offer points for reuse of building materials (particularly on-site) and use of recycled materials. If renovations at an existing facility call for the demolition of existing brick masonry constructions, the rubble could be included as RBMA in new concrete pavement, sidewalks, or curb and gutter. Other potential uses for RBMAC could include those in the precast concrete industry, particularly in architectural precast concrete applications. In addition to providing acceptable strength and economy, the color of RBMA could be an attractive component of architectural precast concrete panels or other façade components. This paper explores the feasibility of use of RBMAC in several types of sustainable construction initiatives, based upon the findings of previous work with RBMAC produced from construction and demolition waste from a case study site. Guidance for obtaining and using RBMA is presented, along with a summary of material properties of RBMAC that will be useful to construction professionals.

• Journal of Practical Engineering Education
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• v.15 no.2
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• pp.259-271
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• 2023

The purpose of this study is to prepare a plan to activate vocational training through a company-customized qualification system that meets the needs of the industry and responds promptly to changes in the external environment and trends. The BRIDGE 3.0 model was presented as Establishment of qualification system based on education and training result certification, a customized qualification operation system based on local companies by setting the qualification system as a strategy centered on companies that are consumers. To this end, the current status and limitations of vocational competency development projects, the current status and limitations of the domestic qualification system, government policies related to vocational competency development, FGI of corporate personnel managers, surveys of personnel managers of SME, expert advice.

• Korean Journal of Materials Research
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• v.33 no.11
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• pp.447-457
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• 2023

Single-atom Pd clusters anchored on t-BaTiO₃ material was synthesized using hydrothermal and ultrasonic methods for the effective piezoelectric catalytic degradation of pollutants using vibration energy. XRD patterns of BaTiO₃ loaded with monoatomic Pd were obtained before and after calcining, and showed typical cubic-phase BTO. TEM and HAADF-STEM images indicated single-atom Pd clusters were successfully introduced into the BaTiO₃. The piezoelectric current density of the prepared Pd-BaTiO₃ binary composite was significantly higher than that of the pristine BaTiO₃. Under mechanical vibration, the nanomaterial exhibited a tetracycline decomposition rate of ~95 % within 7 h, which is much higher than the degradation rate of 56.7 % observed with pure BaTiO₃. Many of the piezo-induced electrons escaped to the Pd-doped BaTiO₃ interface because of Pd's excellent conductivity. Single-atom Pd clusters help promote the separation of the piezo-induced electrons, thereby achieving synergistic catalysis. This work demonstrates the feasibility of combining ultrasonic technology with the piezoelectric effect and provides a promising strategy for the development of ultrasonic and piezoelectric materials.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.771-777
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• 2023

This study examines the strategy of using literary works to effectively present the emotions, narrative, and characters of a drama through the drama "I'll Visit You When the Weather is Good" (2020). The drama uses poetry to effectively show the internal conflicts of the characters, allowing the viewers to understand the characters much more closely. It also shows the narrative of relationship change and growth between the characters through the narrative of a fairy tale. On the other hand, by showing still cuts of the characters' diaries in each episode, it creates a lyrical effect, as if watching the drama is like reading a literary work. In this way, the drama "I will visit you when the weather is nice" actively utilizes literature to help viewers relate to the narrative of growth and healing and experience it as their own, thus creating a three-dimensional image of the healing effect of literature.