Being in a stable continental region (SCR) with a limited history of instrumentation, South Korea has not collected sufficient instrumental data for data-driven ground motion models. To address this limitation, we investigated the suitability of the hybrid ground motion simulation method that Graves and Pitarka (2010, 2015) proposed for simulating earthquake ground motions in South Korea. The hybrid ground motion simulation method used in this study relies on region-specific parameters to accurately model phenomena associated with the seismic source and the wave propagation. We initially employed relevant models and parameters available in the literature as a practical approach. We incorporated a three-dimensional velocity model developed by Kim et al. (2017) and a one-dimensional velocity model presented by Kim et al. (2011) to account for the crustal velocity structure of the Korean peninsula. To represent the earthquake source, we utilized Graves and Pitarka’s rupture generator algorithm along with a magnitude-area scaling relationship developed for SCR by Leonard (2014). Additionally, we assumed the stress and attenuation parameters based on studies of regional seismicity. Using the implemented platform, we simulated the 2016 Mw5.57 Gyeongju earthquake and the 2017 Mw5.4 Pohang earthquake. Subsequently, we compared results with recorded accelerations and an empirical ground motion prediction equation at strong motion stations. Our simulations had an overall satisfactory agreement with the recorded ground motions and demonstrated the potential of broadband hybrid ground motion simulation for engineering applications in South Korea. However, limitations remain, such as the underestimation of long-period ground motions during the 2017 Pohang earthquake and the lack of a model to predict the ground motion amplification associated with the near-surface site response accurately. These limitations underscore the importance of careful validation and refinement of region-specific models and parameters for practically implementing the simulation method.

Interim dry cask storage systems comprising AISI 304 or 316 stainless steel canisters have become critical for the storage of spent nuclear fuel from light water reactors in the Republic of Korea. However, the combination of microstructural sensitization, residual tensile stress, and corrosive environments can induce chloride-induced stress corrosion cracking (CISCC) for stainless steel canisters. Suppressing one or more of these three variables can effectively mitigate CISCC initiation or propagation. Surface-modification technologies, such as surface peening and burnishing, focus on relieving residual tensile stress by introducing compressive stress to near-surface regions of materials. Overlay coating methods such as cold spray can serve as a barrier between the environment and the canister, while also inducing compressive stress similar to surface peening. This approach can both mitigate CISCC initiation and facilitate CISCC repair. Surface-painting methods can also be used to isolate materials from external corrosive environments. However, environmental variables, such as relative humidity, composition of surface deposits, and pH can affect the CISCC behavior. Therefore, in addition to research on surface modification and coating technologies, site-specific environmental investigations of various nuclear power plants are required.

Recently, steel dampers are widely used as seismic reinforcement devices. Steel dampers have the advantage of being easy to manufacture and being able to absorb a lot of energy through stable hysteresis behavior. However, there is a possibility that the steel damper may be damaged due to fatigue caused by repeated seismic loads. In this study, the seismic performance of steel dampers and engineering plastic dampers with different physical characteristics were compared and analyzed. In addition, numerical analysis was performed on a hybrid damper that combines a steel damper and an engineering plastic damper. It is more effective to apply engineering plastic dampers to structures that experience significant displacement due to seismic loads. The behavior of hybrid dampers combining steel dampers and engineering plastic dampers is dominated by steel dampers. A hybrid damper in which an engineering plastic damper yields after a steel damper yields can effectively respond to various seismic loads and secure high ductility and excellent seismic performance.

최근 인공지능 분야에서 가장 활발히 연구되고 있는 거대 언어 모델은 교육에 대한 응용 가능성을 보 이며, 교육학의 거의 모든 분야에서 그 활용 방안이 연구되고 있다. 이러한 연구는 공학 교육에서도 주목 받고 있다. 그러나 구체적인 활용 분야와 방법에 대해서는 아직 많은 연구가 필요한 상황이다. 특히, 거대 언어 모델을 이용한 교육과정 설계와 개선에 대한 연구는 인공지능 공학과 교육학 두 분야에서 모두 중요한 연구 과제로 부각되고 있다. 이러한 응용 필요성에 대한 예시이자 전략으로써, 본 연구는 OpenAI에서 발표한 최신 거대 언어 모델인 ChatGPT-4o를 이용하여 한국과학기술원(KAIST) 공과대학 학부 전공 과 목과 S전자 DS부문(반도체사업부) 직무 사이의 연관성을 분석하고, 그 결과를 기반으로 대학과 기업체 양측에 반도체 산업 인력 양성과 채용에 대한 실질적인 응용 전략을 제안한다. 이를 위해 KAIST 공과대 학 학부과정에 개설된 모든 전공 과목과 S전자 DS부문(반도체사업부)의 직무기술서를 ChatGPT-4o에 학습시켜 각 과목이 특정 제품군, 직무와 가지는 연관성을 특정 범위와 기준에 의거하여 정량화된 점수로 평가했다. 또한, 각각의 직무, 전공, 과목별로 확보한 데이터를 기초적인 통계 분석을 통해 평가했으며, 구직자와 구인자의 활용 가능성에 초점을 두고 특정 전공의 각 직무별 연관성과 특정 직무의 각 전공별 연관성, 그리고 특정 직무 및 전공의 반도체 제품군별 연관성 등 다양한 조건에서 분석을 진행하였다. 또 한 본 전략에 대한 반도체 산업 실무자 견해를 수집하여 실제 전략으로의 활용 가능성을 검증하였다. 분 석 결과, 간단한 질문과 분석만으로도 전공, 교과목별로 유의미한 직무 연관성의 차이를 확인했다. 이러한 결과를 바탕으로 본 연구는 대학 교육과정의 개선과 기업 채용 및 양성 과정에서의 응용 전략을 제시한 다. 이 연구는 대학과 산업 간의 협력을 통해 인적자원 개발과 채용 효율성 증대에 기여할 것으로 기대한 다. 또한, 후속 연구로 구직자와 구인자, 교수자 등 본 연구의 효과를 확인할 수 있는 집단을 대상으로 한 대규모 설문조사 및 전문가그룹 대상 질적연구 등을 제안하여 실제 활용도와의 비교 분석 연구를 제안 한다. 결론적으로, 본 연구는 거대 언어 모델을 활용하여 필요한 인재를 양성하기 위한 교육 과정 설계의 구체적인 응용 가능성을 제시함으로써, 인공지능을 이용한 교육 분야에 대한 기여 방안을 모색한다.

This study evaluates the balance between cellular removal and extracellular matrix (ECM) preservation in cardiac tissue engineering by comparing chemical and physical decellularization methods. Cardiac tissues were treated with chemical agents (sodium dodecyl sulfate and Triton X-100) and physical methods (freeze-thawing and ultrasound). These methods were assessed based on residual cellular content, DNA quantification, ECM structural integrity, and preservation of key ECM components like collagen and glycosaminoglycan (GAG). The results revealed that while chemical methods, particularly SDS, achieved more complete cell removal, they significantly compromised ECM integrity. In contrast, physical methods, such as freeze-thawing, preserved ECM structure more effectively, despite moderate cellular removal. The findings underscore the importance of tailoring decellularization techniques to specific cardiac tissue engineering needs, with chemical methods excelling in cell removal and physical methods offering superior ECM preservation. Future research should aim to optimize these methods to achieve a better balance between decellularization efficiency and ECM integrity.

One of the key challenges for the commercialization of carbon nanotube fibers (CNTFs) is their large-scale economic production. Among CNTF spinning methods, surfactant-based wet spinning is one of the promising techniques for mass producing CNTFs. Here, we investigated how the coagulation bath composition affects the spinnability and the properties of CNTFs in surfactant-based wet spinning. We used acetone, DMAc, ethanol, and IPA as coagulants and analyzed the relationship between coagulation bath composition and the properties of CNTFs in terms of kinetic and thermodynamic coagulation parameters. From a kinetic perspective, we found that a low mass transfer rate difference (MTRD) is favorable for wet spinning. Based on this finding, we mixed the coagulant bath with solvent in a proper ratio to reduce the MTRD, which generally improved the wet spinning. We also showed that the coagulation strength, a thermodynamic parameter, should be considered. We believe that our research can contribute to establishment of surfactant-based wet spinning of CNTFs.

This paper presents a path planning optimization model for the engineering units to install obstacles in the shortest time during wartime. In a rapidly changing battlefield environment, engineering units operate various engineering obstacles to fix, bypass, and delay enemy maneuvers, and the success of the operation lies in efficiently planning the obstacle installation path in the shortest time. Existing studies have not reflected the existence of obstacle material storage that should be visited precedence before installing obstacles, and there is a problem that does not fit the reality of the operation in which the installation is continuously carried out on a regional basis. By presenting a Mixed Integrer Programming optimization model reflecting various constraints suitable for the battlefield environment, this study attempted to promote the efficient mission performance of the engineering unit during wartime.

CO2 photocatalytic reduction is a carbon–neutral renewable energy technology. However, this technology is restricted by the low utilization of photocatalytic electrons. Therefore, to improve the separation efficiency of photogenerated carriers and enhance the performance of CO2 photocatalytic reduction. In this paper, g-C3N4/Pd composite with Schottky junction was synthesized by using g-C3N4, a two-dimensional material with unique interfacial effect, as the substrate material in combination with the co-catalyst Pd. The composite of Pd and g-C3N4 was tested to have a strong localized surface plasmon resonance effect (LSPR), which decreased the reaction barriers and improved the electron utilization. The combination of reduced graphene oxide (rGO) created a π–π conjugation effect at the g-C3N4 interface, which shortened the electron migration path and further improved the thermal electron transfer and utilization efficiency. The results show that the g-C3N4/ rGO/Pd (CRP) exhibits the best performance for photocatalytic reduction of CO2, with the yields of 13.57 μmol g− 1 and 2.73 μmol g− 1 for CO and CH4, respectively. Using the in situ infrared test to elucidate the intermediates and the mechanism of g-C3N4/rGO/Pd (CRP) photocatalytic CO2 reduction. This paper provides a new insight into the interface design of photocatalytic materials and the application of co-catalysts.

The lightweight and high strength characteristics of aluminum alloy materials make them have promising prospects in the field of construction engineering. This paper primarily focuses on aluminum alloy materials. Aluminum alloy was combined with concrete, wood and carbon fiber reinforced plastic (CFRP) cloth to create a composite column. The axial compression test was then conducted to understand the mechanical properties of different composite structures. It was found that the pure aluminum tube exhibited poor performance in the axial compression test, with an ultimate load of only 302.56 kN. However, the performance of the various composite columns showed varying degrees of improvement. With the increase of the load, the displacement and strain of each specimen rapidly increased, and after reaching the ultimate load, both load and strain gradually decreased. In comparison, the aluminum alloy-concrete composite column performed better than the aluminum alloy-wood composite column, while the aluminum alloy-wood-CFRP cloth composite column demonstrated superior performance. These results highlight excellent performance potential for aluminum alloy-wood-CFRP composite columns in practical applications.

스마트팜형 시설 딸기에 예찰 없이 작물 정식 초기에 천적을 먼저 적용하는 생태공학적 Natural Enemy in First (NEF) 기법이 총채벌레류 와 진딧물류의 밀도에 미치는 영향을 확인하였다. 대조구는 약제를 처리하여 비교하였다. NEF 처리구에서 총채벌레류와 진딧물류의 천적과 서식 처로 참멋애꽃노린재와 Portulaca sp.를 적용하여 작기 종료시점까지 해충의 밀도를 대조구와 유사하게 효과적으로 관리할 수 있었다.