This study evaluated the safety impact of automated traffic enforcement cameras targeting tailgating behavior at signalized intersections by comparing traffic conditions shortly after installation and one year later. The Kukkiwon intersection in Gangnam-gu, Seoul, South Korea was selected as the study site. Individual vehicle speeds, accelerations, and subsequent distances were extracted from video data using YOLOv8 and ByteTrack, which are advanced deep learning-based object detection and tracking algorithms. Surrogate safety measures (SSM), such as time to collision (TTC), modified time to collision (MTTC), and proportion of stopping distance (PSD), were calculated to assess changes in traffic safety. Every SSM indicated an improvement one year after the installation of enforcement cameras, suggesting a reduction in collision risks. In particular, the PSD indicator showed a notable improvement, reflecting a better maintenance of safe following distances. These results highlight the effectiveness of automated enforcement in improving intersection safety and suggest its scalability to other intersections with similar tail-gating issues. Future research should explore the long-term and multisite effects using diverse intersection types and behavioral indicators.

Background: The growing need for objective and accurate evaluation in Taekwondo poomsae competitions has highlighted the limitations of subjective human judgment. Objectives: This study aims to develop an automated scoring framework using camera-based pose estimation and advanced neural networks to improve the consistency and accuracy of poomsae evaluation. Design: Comparative analysis of neural network architectures on a large-scale dataset of poomsae movements. Methods: A dataset of 902,306 labeled frames, captured from 48 participants performing 62 distinct movements using synchronized multi-view cameras, was analyzed. Five neural networks (HNN, 1D CNN, GCN, MLP, SANN) were implemented and evaluated using accuracy, precision, recall, and F1-score. Results: The HNN demonstrated superior performance with an F1-score of 0.78 in classifying Taekwondo poomsae postures. The 1D CNN followed with an F1-score of 0.76, while GCN, MLP, and SANN achieved F1-scores of 0.74, 0.70, and 0.66, respectively. The HNN's hierarchical feature extraction approach proved effective in capturing the complex spatial and temporal patterns inherent in poomsae movements. Conclusion: Hierarchical Neural Networks outperform other architectures in poomsae classification, establishing a foundation for objective and scalable scoring systems in competitive settings.

인공관절 치환술 환자의 합병증 진단을 위한 자기공명영상 검사에서 발생한 금속 인공물을 감소시키는 VAT(view angle tilting) 기법과 딥러닝 알고리즘 중 K-공간 기반의 deep resolve(boost, sharp, DR)를 적용하여 그 유용성 에 대해 평가하고자 하였다. 자체 제작 팬텀과 3T 장비로 일반적인 VAT, DR이 적용된 VAT로 T1 강조영상, T2 강조영상, 단시간 반복 회전 연쇄기법(short tau inversion recovery, STIR) 영상들을 병렬영상 가속계수 2, 3, 4를 적용하여 획득하였다. 획득된 영상에서 왜곡도, 팬텀 바닥에서 금속 인공물까지 거리, 신호대잡음비를 정량적 평가하였고, 영상 품질은 정성적 평가하였다. 왜곡도는 일반적인 VAT와 DR이 적용된 VAT의 T1 강조영상, T2 강 조영상, STIR 모두 유의한 차이가 없었다(p>0.05). 또한 금속 인공물까지 거리도 T1 강조영상, T2 강조영상, STIR 모두 유의한 차이가 없었다(p>0.05). 신호대잡음비는 일반적인 VAT보다 DR이 적용된 VAT의 가속계수 4에서 T1 강조영상은 103%, T2 강조영상은 85.2%, STIR은 73.3% 최대로 증가하였고, 영상품질 평가점수는 T1 강조영상은 5점, T2 강조영상은 4.6점, STIR은 4.8점으로 가장 좋았다. 본 연구를 통해 VAT 기법의 영상품질 저하를 DR 기술 로 개선할 수 있었다. 금속 인공물이 발생했을 때 DR이 적용된 VAT의 가속계수를 4로 적용한다면, 검사시간을 단 축하면서 보다 진단적 가치가 높은 영상을 획득할 수 있을 것으로 사료된다.

체인 형태의 코발트(Co) 메조스피어를 템플레이트로 활용하여 금(Au) 및 팔라듐(Pd) 전구체와의 2단계 갈바닉 치환 반응을 통해 비백금 기반의 AuPd 복합 촉매를 합성하였다. NaAuCl4 전구체로부터 합성된 AuPd-Cl(50) 촉매는 높은 비표면적과 다공성 구조를 통해 산소환원반응(ORR)에서 우수한 촉매 활성을 나타냈으며, 상용화된 Pt-20/C 및 Pd-20/C 촉매 대비 낮은 개시(onset) 전위와 높은 한계 전류 밀도 및 향상된 n 값을 보였다. Koutecky-Levich plot 분 석 결과, ORR이 4-전자 전달 메커니즘에 근접함을 확인하였으며, 메탄올 내성과 안정성 실험에서도 우수한 성능을 보였다. AuPd-Cl(50) 촉매는 경제적이고 효율적인 백금 대체 촉매로서 알칼리 연료전지 및 메탄올 기반 연료전지 응 용 가능성을 제시한다.

The purpose of this study was to derive an optimal mix design for bridge deck pavements that can compensate for the limitations of latexmodified concrete (LMC). To address the limitations of LMC, this paper proposes the incorporation of silica fume into LMC. Concrete mixtures with varying ratios of latex and silica fume were prepared, and tests for compressive strength, flexural strength, and chloride-ion penetration resistance were conducted to compare and analyze the fundamental performance of each mix. Latex contributed to the improvement of the initial pore structure and significantly affected the chloride-ion penetration resistance in the early stages of curing. However, its influence gradually diminished over time. In contrast, silica fume induced additional C-S-H formation and further improved the pore structure through pozzolanic reactions as time progressed, thus exerting a greater impact in the later stages of curing. The L7-SF8 variable demonstrated the best performance in terms of compressive strength and chloride-ion penetration resistance. Given the characteristics of bridge-deck pavements, this variable is considered the most suitable for ensuring long-term durability. Therefore, this paper proposes a mixture of 7% latex and 8% silica fume as the optimal mix design.

도로 위 노면전차 트램를 포함한 다양한 이동수단 흐름을 원활하게 유지하기 위해서는 효율적인 교통 신호 제어가 필요하다. 검증 되지 않은 기술의 현장 평가는 교통안전 측면에서 위험하기에 대부분 가상환경을 통해 적용 기술검증을 선행한다. 본 연구는 다양한 교통신호 제어 알고리즘을 센터 수준에서 적용하는 가상 실험환경 마련을 위한 기능적 요구사항을 정의한다. 기능적 요구사항으로 가 상환경 센터 기반으로 실험을 시작하거나 중지하는 기능, 교통량 등 입력값을 입력하는 기능 등의 기본적 요구사항을 도출하였다. 이 렇게 정의된 기능적 요구사항은 향후 트램 등 다양한 교통수단을 대상으로 하는 가상환경 센터 구축 과정에 효율적으로 참조될 수 있 을 것으로 기대된다.

Considering the various health problems associated with obesity in dogs, including renal diseases, joint disorders, and skin diseases, effective management strategies and guidelines are urgently needed. This situation has led to a growing demand for veterinary medications aimed at addressing obesity in dogs. However, the field faces a significant hurdle due to the absence of standardized guidelines for assessing the effectiveness of these anti-obesity medications in dogs. In response to this gap, the Animal and Plant Quarantine Agency (APQA) in Korea has made a crucial step by introducing clinical trial guidelines to evaluate the efficacy of treatments for canine obesity, specifically aimed at approving veterinary medicinal products. The guidelines outlined the selection criteria for target dogs, highlighting the importance of consistency within the control and treated groups. Treatment efficacy is subsequently evaluated by physical examination, body fat reduction, and biochemical indicators. In addition, the guidelines cover dosage and administration, monitoring after dosing, and statistical analysis. By doing so, this guideline not only highlights the significance of the APQA’s initiative in improving the care of obese dogs but also provides practical insights to enhance the standardization and effectiveness of clinical trials in veterinary medicine.

The interface area of the face sheet and core of the sandwich composite is seen as a weakness due to its low de-bonding toughness. To overcome this concern, it is critical to develop a suitable modification strategy to enhance the de-bonding toughness of the face sheet/core interface. In the present study, the corrugated core reinforced sandwich composite was prepared through co-curing and secondary bonding approaches. The MWCNTs reinforced adhesive was induced in the face sheet/core interface in different weight concentrations. The MWCNT-reinforced adhesive was prepared using the sonication technique, and its dispersion was examined using atomic force microscopy (AFM). The three-point bending test revealed that sandwich composite prepared using the co-cure method has higher flexural strength than secondary bonded samples due to better bonding face sheet and corrugated core. Compared with MWCNT-free corrugated core reinforced co-cured sandwich composites (CCSC), the flexural strength of 1 wt.% MWWCNT-induced sandwich composite was increased by 101.28%. The microstructural study showed that secondary bonded samples had extensive fibre breakage at the face plate due to early de-bonding of the face sheet and corrugated core. Furthermore, the free vibrational analysis was performed to evaluate the natural frequency and damping values of the corrugated core reinforced sandwich composite. The modal test results indicated that inducing 1wt.% MWCNTs in the face sheet/core interface had enhanced the natural frequencies of co-cured sandwich composites. The present study provides a suitable method to address the weaker de-bonding toughness concerns of face sheet/core interface region of sandwich structures.

국토 대부분인 산지로 구성된 국내의 특성상 대형 산불 사례가 지속적으로 보고되고 있으며, 동해안에서 다발적으로 발생하 는 과거 대비 최근 서해안의 산림원이 확대됨에 따라 점차 전국화되고 있는 실정이다. 본 연구에서는 이러한 산불 발생 주기의 증가로 인한 산지에 설치되어 있는 사방댐의 산불에 의한 영향성 평가를 수행하였다. 대상 구조물은 선행 연구에서 사용된 강재, GFRP 및 CFRP를 사용한 투과형 사방댐으로 선정하였으며, 각 재료별 구조재를 사용한 투과형 사방댐의 안전성 평가를 위해 상용 유한요소해석 프로그램인 ABAQUS를 활용하였다. 해석 결과, 600℃ 수준에서 파괴가 발생한 강재 구조재에 반해 FRP 구조재는 800℃ 이상에도 파 괴되지 않음을 확인하였다. 또한, FRP 구조재는 강재 대비 10.30%∼11.20% 가량 낮은 응력 수준을 보였으며, 최대 변위는 약 73.1배, 17.9배 증가하는 것으로 측정되었다. 콘크리트로 구성된 댐체의 경우, 구조재의 설치부에 응력이 집중됨을 알 수 있으며, 압축 측은 모 든 구조재에서 안전한 것으로 나타났지만, 인장 측은 600℃ 이상에서 모든 구조재의 댐체 콘크리트가 파괴됨을 확인하였다. 따라서, 사 방댐 설계 시 이러한 강도 감소를 충분히 고려할 필요가 있을 것으로 사료된다. 댐체와 구조재가 연결되는 고정부의 경우, GFRP 및 CFRP 구조재가 강재 구조재 대비 약 82.43%, 67.63% 감소된 반력을 보이는 것으로 확인되었다. 이러한 결과는 FRP 구조재의 높은 변위가 하중을 소산하여 고정부에 적은 영향을 미치는 것으로 생각된다. 결론적으로, FRP 구조재를 사용하는 것은 기존 강재 구조재 대비 고온 저항성 측면에서 다양한 이점을 얻을 수 있으나, 수치해석적 접근법으로 평가된 결과이므로 향후 지속적인 연구로 신뢰성을 검증할 필요가 있다.

In this study, various pre-treatment methods were evaluated for microalgae separation. These methods aimed to facilitate safe, rapid, and cost-effective online imaging for real-time observation and cell counting. As pre-treatment techniques, heating, chemical hydrolysis, heating combined with chemical hydrolysis, and sonication were employed. The effectiveness of these methods was evaluated in the context of online imaging quality through experimentation on cultivated microalgae (Chlorella vulgaris and Scenedesmus quadricauda). The chemical treatment method was found to be inappropriate for improving image acquisition. The heating pre-treatment method exhibited a drawback of prolonged cell dispersion time. Additionally, the heating combined with chemical hydrolysis method was confirmed to have the lowest dispersion effect for Chlorella vulgaris. Conversely, ultrasonication emerged as a promising technique for microalgae separation in terms of repeatability and reproducibility. This study suggests the potential for selecting optimal pre-treatment methods to effectively operate real-time online monitoring devices, paving the way for future research and applications in microalgae cultivation and imaging.