Buckling Restrained Braces can not only express the strength considered at the time of design, but also reduce the seismic load by energy dissipation according to the plastic behavior after yield deformation of the steel core. The physical characteristics and damping effect may be different according to the buckling prevention method of the steel core by the lateral restraint element. Accordingly, in this study, To compare hysteresis characteristics, Specimen(BRB-C) filled with mortar, specimen(BRB-R) combined with a buckling restraint ring and Specimen(BRB-EP) filled with engineering plastics was fabricated, and a cyclic loading test was performed. As a result of the cyclic loading test, the maximum compressive strength, cumulative energy dissipation and ductility of each test specimen was similar. But in case of the cumulative energy dissipation and ductility, BRB-C filled with the mortar specimen showed the lowest. This is considered to be because the gap between the steel core and the reinforcing material for plastic deformation was not uniformly formed by pouring mortar around the core part.

Structural vibration induced by earthquake hazards is one of the most significant concerns in structure performance-based design. Structural hazards evoked from seismic events must be properly identified to make buildings resilient enough to withstand extreme earthquake loadings. To investigate the effects of combined earthquake-resistant systems, shear walls and five types of dampers are incorporated in nineteen structural models by altering their arrangements. All the building models were developed as per ACI 318-14 and ASCE 7-16. Seismic fragility curves were developed from the incremental dynamic analyses (IDA) performed by using seven sets of ground motions, and eventually, by following FEMA P695 provisions, the collapse margin ratio (CMR) was computed from the collapse curves. It is evident from the results that the seismic performance of the proposed combined shear wall-damper system is significantly better than the models equipped with shear walls only. The scrutinized dual seismic resisting system is expected to be applied practically to ensure a multi-level shield for tall structures in high seismic risk zones.

The recent increase in earthquake activities has highlighted the importance of seismic performance evaluation for civil infrastructures. In particular, the container crane essential to maintaining the national logistics system with port operation requires an exact evaluation of its seismic response. Thus, this study aims to assess the seismic vulnerability of container cranes considering their seismic characteristics. The seismic response of the container crane should account for the structural members’ yielding and buckling, as well as the crane wheel’s uplifting derailment in operation. The crane’s yielding and buckling limit states were defined using the stress of crane members based on the load and displacement curve obtained from nonlinear static analysis. The derailment limit state was based on the height of the rail, and nonlinear dynamic analysis was performed to obtain the seismic fragility curves considering defined limit states and seismic characteristics. The yield and derailment probabilities of the crane in the near-fault ground motion were approximately 1.5 to 4.7 and 2.8 to 6.8 times higher, respectively, than those in the far-fault ground motion.

본 연구는 빅데이터를 통해 남북통일에 관한 한국 사회의 인식을 분석 하고 그를 통한 함의를 도출하여 미래 한반도 통일에 관한 시사점을 얻 고자 하였다. 이를 위해 2003년부터 2022년 5월까지, 역대 4개 정부를 분석대상 기간으로 구분 설정하고 포털 및 언론보도 빅데이터 총 115,975건의 데이터를 수집하여 텍스트마이닝과 사회연결망 분석을 수행 하였다. 연구 결과, 정부 시기별 통일에 관한 사회적 인식의 특성을 확인 하였으며 외교, 정치, 군사, 경제, 사회·문화 측면의 공통 키워드를 도출 하여 그에 따른 한반도 통일에 관한 발전적 방향을 제언하였다.

지식기반사회에서 산학협력의 중요성이 지속적으로 높아짐에 따라 정부는 산학협력 관련 다양한 사업을 추진하고 있다. 하지만 정부의 많은 지원에도 불구하고 만족스러운 성과를 거두지 못하고 있어 산학협력 성과를 확산하기 위한 실증적 성과분석의 필요성이 커지고 있다. 본 연구에서는 DEA를 활용하여 LINC+ 참여 대학의 산학협력 성과를 분석하였다. CCR 모형과 BCC 모형을 활용하여 효율성 분석을 수행하였으며, 규모효율성 분석을 통해 규모수익과 비효율 원인을 파악하였다. 또한 비효율적으로 운영되는 대학에 대하여 효율성 개선목표를 제시하였다. 분석 결과 대학이 위치한 지역에 따라 LINC+ 성과의 차이가 있으며, 대학별 비효율 개선을 위한 목표들이 상이한 것으로 나타났다. 본 연구 결과는 대학의 운영 효율성 제고와 경쟁력 강화에 기여할 것으로 기대되며, LINC+의 후속 사업 계획 수립에도 활용될 수 있을 것이다.

The forms and demands of language learning are changing in the pandemic era. Learners no longer rely solely on a formal language curriculum. Instead, they are using various informal language learning (ILL) channels. Although informal language learning has been in the spotlight and is growing, more research on ILL is needed. In this study, ILL taking place through an online community was analyzed. Articles from the Korean learning community (r/Korean in Reddit) were collected, and the topic modeling technique, Latent Dirichlet Allocation, was conducted on the collected data. As a result, seven major topics were selected. The most common topics in all posts were issues faced by beginner learners, followed by vocabulary and sentence meanings, interest in Chinese characters and applications of Korean language skills, culture and daily life, translation, online learning materials, and Korean phonics. Through this, the interests of ILL learners and the characteristics of learners could be identified. Due to the nature of ILL, in which a formal curriculum does not exist, it was found that questions about general strategies for learning and questions that could not be solved in formal language education were most prominent. In addition, the characteristics of ILL learners who actively sought learning content and materials were also found.

본 연구는 함초를 섭취한 동물쥐에서 비만과 혈중 지질의 개선 효과에 대한 실험을 체계적 문헌고찰을 통해 통계적으로 분석하였다. 각각의 개별 연구는 PubMed, Embase, RISS, DBpia, NDSL과 같은 데이터베이스로부터 수집되었다. 통계분석을 통해 효과크기를 측정하기 위해 Review Manager 5.3 프로그램이 이용되었고 총 9개의 연구가 최종적으로 포함되었다. 비만유발 흰쥐에서 함초의 섭취는 몸 무게를 유의적으로 감소시켰다. 그러나, 식이효율, 간지수와 총콜레스테롤에서 통계적 유의성이 없었다. 또한, 효과크기가 중성지방은 감소하고, 고밀도 콜레스테롤은 증가하였다. 이러한 통계적 분석은 함초가 강력한 항비만과 혈중 지질 개선 효과를 가진다는 결과는 보여준다.

Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, analysis and modification of prototypes of electron beam filaments for mass production were dealted with.

목적: 본 논문의 목적은 연구 문헌 중 요통 환자에게 보행운동을 적용한 무작위 대조군 실험설계를 메타 분석을 하여 통증과 장애지수에 대한 효과를 알아보고자 하였다. 방법: 본 논문은 다음 데이터베이스에서 검색하였다: Google scholar, PubMed, Sciencedirect, KISS, RISS, NDSL. 지난 10년간 영어나 한국어로 된 논문 중, 요통이 있는 환자들이 보행운동을 하였을 때, 통증과 장애지 수를 연구한 논문들을 검색하였다. 이 논문에는 (1) 요통이 있는 환자, (2) 중재에는 보행운동이 포함되며, (3) 평가 지표에는 통증과 장애지수가 포함되었다. 최종 결과로 35개의 논문을 확인하였고, 그중 15개의 논문이 충족되었다. 결과: 본 논문은 요통 환자를 대상으로 보행운동을 중재로 주었을 경우의 논문 15편을 최종적으로 선정하 였고 분석하였다. 통증과 장애지수와 관련되어 각각 12개의 논문을 분석하였다. 통증과 관련된 12개의 논문의 효과 크기는 중간의 효과 크기나 나타났고, 장애지수와 관련된 12개의 논문의 작은 효과 크기가 있었다. 결론: 보행운동은 요통 환자들의 통증을 감소시키고 장애지수를 줄이는데 유의미한 효과가 있다. 따라서 보 행운동은 요통을 지닌 사람들에게 긍정적인 영향을 미칠 것으로 사료된다.

Due to its excellent processability, thermal conductivity and high corrosion resistance, copper tubes applied to heat exchangers are being joined through brazing to increase heat exchange efficiency. In order to improve performance, the issue of joint quality of copper tubes, a major member of heat exchangers, is emerging, so research is needed to obtain excellent joint quality of brazing joints that may be damaged. In this study, the quality change of joints according to process variables was studied through induction heating brazing experiments using high frequency. The depth of penetration, which indicates the quality of the junction, was measured, and the center position of the high-frequency electrode and the height of the electrode, which change the location of the heat source applied to the junction, were selected as process variables. Lastly, the thermal image data obtained between the brazing experiments were obtained and the joint quality according to the temperature gradient of the joint was analyzed.