As domestic traffic policies have shifted from vehicle-centric approaches to a ‘Safe Speed’ paradigm, the installation of roundabouts has surged. However, existing studies based on linear statistical models have failed to identify the complex non-linear interactions between geometric features and accident severity, limiting their ability to provide concrete design thresholds. To overcome the lack of traffic volume data, this study developed a geometry-based Design Capacity Index (DCI) and proposed a new analytical framework using the Equivalent Property Damage Only (EPDO) rate per unit capacity as the dependent variable. Utilizing a dataset of nationwide roundabouts (2007–2020), a grid search-optimized eXtreme Gradient Boosting (XGBoost) model and SHAP analysis were applied, achieving a 40.5 % performance improvement over linear baselines. The results revealed that circulatory roadway width was a dominant factor; contrary to the 'Road Diet' theory, ensuring 'Geometric Sufficiency' (wider lanes) proved more effective for safety in medium-to-large roundabouts. Furthermore, a 'Broad Optimal Zone' was identified within an inscribed circle diameter (ICD) of 35–70 m, while a 'Paradox of Scale' emerged beyond 70 m where safety benefits plateaued. Additionally, raised crosswalks served as essential offset measures, consistently reducing accident costs regardless of the intersection size. Based on these findings, this study provides empirical evidence for revising design guidelines to prioritize the 35–70 m ICD range and advocates for the mandatory installation of physical calming measures in oversized roundabouts.

This study identifies critical ESG decision factors for road pavement maintenance during the design phase, which dictate approximately 80% of infrastructure performance outcomes. A two-stage analytical framework was employed. First, the fuzzy-Delphi method filtered 72 industry indicators into 20 core factors based on expert consensus (defuzzification value≥0.7). Second, a revised importance-performance analysis prioritized these factors across five regional types (urban, mountainous, rural, coastal, and expressway) using a 10-member expert panel. Results revealed distinct regional priorities: urban areas emphasized low-noise construction, mountainous areas focused on ecological restoration, coastal areas prioritized durability, and expressways required worker safety system integration. Climate risk assessment (G10) and pollution prevention (E19) emerged as priorities across all regions. These findings prove that ESG evaluation in road maintenance must incorporate weighted regional differentiation rather than uniform criteria. Policy recommendations include implementing mandatory regional ESG checklists in design guidelines and establishing BIM-integrated performance-tracking systems.

철근 콘크리트의 부식으로 인해 비부식성 대체재의 채택이 촉진되었으며, GFRP 철근은 가장 널리 채택된 경제적이고 균형 잡힌 성능 옵션 중 하나이다. GFRP 철근의 탄성 계수는 강철보다 낮아 완전한 대체가 어렵다. 하지만 최근 GFRP의 탄성 계수는 국제 기준 30∼40 GPa에서 약 60 GPa(국외 생산 기준), 50 GPa(국내 생산 기준)로 증가했습니다. 그러나 대부분의 설계 방정식은 기존의 저탄성계수 GFRP를 기준으로 보정되었다. 본 연구에서는 고탄성계수 GFRP 보강근으로 보강된 두 개의 콘크리트 보의 휨 거동을 분석하며, 실험 하중-변위 응답을 Adam, ACI 440.1R-06, CSA S806-12 및 최신 ACI 440.11-22의 예측값과 비교한다. 이 모델들은 모두 비균열 영역의 초기 경사와 일치하지만, 저탄성계수 GFRP를 사용한 보정으로 인해 실제 강성을 과소평가하고 처짐 을 과대 예측하는 경향이 있습니다. 균열 발생 후 편차가 증가하며, 이때, Adam 방정식이 가장 큰 편차를 보인다. 이는 기존 모델의 한계를 보여주며, 변위 제어가 매우 중요한 경우 기존 모델의 사용에 신중해야 함을 보여준다.

The design code specifies the seismic loads for non-structural components (NSC) regardless of their planar locations. Thus, structures with irregular geometry that exhibit torsional behavior may experience greater seismic loads than those specified by the design code. This study assessed the adequacy of the code-specified equivalent static loads using nonlinear dynamic analysis results from structures intentionally designed to be eccentric, and finally proposed a formula that accounts for torsional amplification effects in buildings. The analysis results indicated that the code-specified equivalent static loads were conservative in the lower stories or near the center of mass. On the other hand, the dynamic analysis-based loads exceeded the equivalent static load in the outer perimeter of the mid- and upper stories. Accordingly, a torsional amplification factor equation was proposed, which is a function of the building's eccentricity ratio and the relative distance from the center of mass. The proposed equation applies to the NSC installed in the stories above the midpoint of the total building height. For a building with zero eccentricity or NSC at the center of mass, the function was set to unity.

This study investigates the repeated impact behavior and compression-after-impact (CAI) performance of triaxially braided carbon/glass fiber-reinforced polymer (C/GFRP) composite tubes. A two-stage experimental strategy was proposed to evaluate the synergistic effect of interlayer hybridization and axial yarn reinforcement on damage evolution and mechanical performance. In Stage I, six hybrid braided tubes with different carbon/glass stacking configurations—including pure carbon, pure glass, layered, and reversed-layered structures—were subjected to repeated low-velocity impacts at 31 J. Micro-CT was employed to reconstruct the internal damage morphology and assess damage accumulation. The optimal interlayer configuration was selected based on impact force, displacement, energy absorption, and internal failure characteristics. In Stage II, the selected structure was further reinforced with four types of axial yarns (none, carbon, glass, and carbon/glass alternating), and their axial compressive and CAI performance after 10 J impact was tested. Results revealed that reversed interlayer design effectively suppressed crack propagation and improved damage tolerance under cyclic impacts. Moreover, the inclusion of hybrid axial yarns significantly enhanced residual compressive strength without compromising energy absorption. This study establishes a lightweight, high-performance braided tube design strategy suitable for aerospace and transportation applications.

This study investigates the Dunhuang medallion patterns of the Tang Dynasty as its primary focus, conducting a systematic analysis of their morphological structures and color characteristics across four distinct historical phases, from the Early to the Late Tang periods. It also elucidates the evolution of patterns, tracing their transformation from the Early Tang's “cross” structure to the Middle-Late Tang's “six-partition” structure. Additionally, it interprets the sociological and cultural significance embedded within this progression. The study integrates shape grammar theory to create a layered deconstruction framework for pattern analysis based on split grammar principles and proposes an innovative design methodology that includes four deduction rules: generative, modifying, inherited, and derivative. New patterns are generated through vectorized extraction and regularized deduction, preserving traditional elements while aligning with modern aesthetics. The method's feasibility and utility were validated through a practical case using the design on a silk scarf, completing a research cycle of “analysis-extraction-derivation-validation.” Research shows that shape grammar provides a systematic method for innovating traditional patterns, while the resulting framework opens new avenues for reinterpreting cultural heritage.

본 연구는 뉴미디어 환경이 문화예술 창의 표현의 방식과 시 각화 구조를 어떻게 변화시키는지 분석하기 위해 문헌 검토와 사례 분석을 병행하여 수행되었다. 본 연구는 텍스트·이미지·영 상·아이콘·그래픽·모션과 같은 시각 요소들이 디지털 플랫폼에서 융합되면서 문화예술 창의 표현의 범위가 확장되고, 이용자의 인지적·정서적·행위적 반응이 다층적으로 형성되는 현상을 확인 하였다. 또한 연구는 뉴미디어 환경에서 시각화 전파의 특징이 실시간 상호작용성, 알고리즘 기반 노출, 이용자 참여도 확장으 로 구조화되며, 이는 창의 콘텐츠가 확산되는 경로와 속도, 해석 방식에 유의미한 차이를 발생시킨다는 점을 밝혔다. 특히 연구 는 예술·디자인·광고 영역에서의 문화예술 창의가 단순한 이미지 표현을 넘어 참여 기반의 ‘확장형 창의(extended creativity)’로 재구성되고, 이는 디지털 정체성 형성, 감성 기반 소비, 참여적 문화의 확산 등 사회문화적 변화와 긴밀히 연결되어 있음을 규 명하였다. 본 연구는 시각화 전파가 창의 산업의 구조적 변화를 견인하고, 뉴미디어 기반 창의 전략이 향후 문화예술 및 디자인 산업 전반의 혁신 방향을 제시할 수 있다는 함의를 제공한다. 본 연구는 향후 뉴미디어 창의 연구가 이용자 경험·디지털 감정· 시각 알고리즘 분석 등으로 확장될 필요가 있음을 제안하며, 문 화예술 기반 창의의 시각화 전파를 이해하기 위한 이론적·방법 론적 기초를 마련하였다.

Background: Children with spastic cerebral palsy (CP) often undergo orthopedic surgery for muscle contractures, followed by rehabilitation to restore mobility. Evidence on intensive rehabilitation with task-oriented therapy (TOT) after low-burden orthopedic surgery is limited. Objects: This study examined the effects of a 16-week intensive rehabilitation program incorporating TOT in a child with spastic CP who received hamstring and adductor lengthening. Methods: A single-case experimental design was used. Assessments included range of motion (ROM), the Gross Motor Function Measure (GMFM), and the Childhood Health Assessment Questionnaire (CHAQ). The participant received structured rehabilitation with TOT 5 times per week for 16 weeks. Results: Improvements were observed in hip abduction ROM, popliteal angle, GMFM, and CHAQ. A previously unachievable task, reaching a walker and walking to a sofa, became independently achievable, representing a meaningful gain in functional mobility. Conclusion: Intensive rehabilitation with TOT after low-burden orthopedic surgery may yield clinically meaningful improvements in motor function and daily activity performance, and support greater independence in children with CP.

Injection molds, composed of components such as upper and lower cores, mold bases, pins, and cooling channels, serve as the primary tooling for manufacturing plastic products. Despite the often simple geometry of molded products, the configuration and design of mold components remain highly complex, making the technical expertise and accumulated know-how of mold designers essential. However, the mold industry is facing increasing difficulties due to the discontinuation of academic programs dedicated to mold design, the aging of experienced designers, and the lack of incoming skilled personnel. To address these challenges, research on automating mold design has continued, and recent advancements in artificial intelligence (AI) have accelerated efforts to internalize expert knowledge through a variety of computational approaches. In this study, we conducted foundational research aimed at constructing a DT-AX platform capable of handling multiple domains by implementing and modularizing diverse processes within a digital-twin (DT) environment and integrating AI modules specialized for each process. Given the input dimensions of a bottle-cap model (diameter and height), the simplified outer dimensions of a core mold were predicted and subsequently used to generate a 3D model. The resulting STEP file was verified to be compatible with commercial CAD and simulation software. Overall, the results demonstrate the feasibility of implementing an automated mold-design module within a digital-twin environment. Future work will focus on diversifying design variables and increasing geometric complexity to develop modules that more closely approximate real-world mold design.

High-entropy alloys (HEA) have emerged as promising structural materials for use in extreme environments where conventional alloys face limitations. In this study, ferritic Fe-Al-Cr-Ni-Ti alloys were developed by employing the HEA design concept to promote coherent L21 precipitation within a BCC matrix. The systematic variation of Al content enhanced lattice coherency, precipitation strengthening, and the rapid formation of protective Al2O3 scales. The alloy with 16 at% Al exhibited superior high-temperature mechanical performance, showing a yield strength of approximately 400 MPa and ~5 % uniform elongation at 700 °C, exceeding the use temperature limit of conventional steels. Steam oxidation tests demonstrated the formation of dense, continuous alumina films, while hot rolling and grain refinement effectively improved room-temperature ductility. These findings indicate that Fe-Al-Cr-Ni-Ti alloys offer a cost-effective pathway to achieve a balanced combination of heat resistance, corrosion resistance, and mechanical processability, suggesting their potential as strong candidates for next-generation energy and high-temperature structural applications.

본 연구는 문자 기호가 도자 조형에서 어떠한 의미와 형식으로 활용되어 왔는지를 살피고, 이를 조형 디자인의 관점에서 정리하는 데 목적을 둔다. 문자는 기록을 위한 체계에서 출발했으나, 회화, 조각, 설치 등 여러 예술 장르에서 이미지와 더불어 표현 재료로 수용되면서 선, 획, 구조가 시각적 구성의 중요한 요소로 자리하였 다. 도자 분야에서도 문자는 기록, 장식, 상징을 비롯한 다양한 기 능으로 조형 디자인 전반을 이루는 요소로 활용되고 있으며, 글자 의 형태는 도자 표면의 질감, 소성 과정의 변화와 어우러져 다양한 시각적 효과를 만들어낸다. 이러한 특성은 문자 기호가 의미와 형 태가 함께 작용하는 시각 언어로 확장되는 배경이 되었고, 개념적 내용의 표현, 특정 경험을 남기는 기록적 접근, 형태의 조합과 변형 을 중심으로 한 조형적 활용 등 여러 방식으로 나타난다. 최근에는 디지털 기반 제작 방식과 인쇄 기술의 도입으로 문자 기호를 보다 자유롭게 적용할 수 있는 환경이 마련되었다. 전통적 으로 축적되어 온 상감, 철화, 인화 기법은 여전히 중요한 제작 기 법이며 전사지, 실크스크린 등 현대적 공정과 결합되면서 새로운 조형 방식이 나타나고 있다. 이러한 흐름은 전통과 현대 기술이 서 로 영향을 주며 문자 기호의 표현 범위를 넓히고 있음을 보여준다. 본 연구는 문자와 기호의 개념적 차이와 시각적 구조, 예술 전반 에서의 수용 양상을 고찰한 뒤, 도자 조형에 나타나는 문자 기호를 개념 중심, 기록 중심, 조형 중심의 세 유형으로 나누어 그 의미를 정리하였다. 또한 전통 시문 기법과 현대적 변용을 비교함으로써 문자 기호가 도자 조형 디자인으로 발전하는 과정에서 나타난 표현 특성과 가능성을 파악하고자 하였다. 이러한 논의는 문자 기호가 도자 조형에서 장식이나 표기 방식, 의미와 구조를 함께 이끄는 조 형 요소로 자리하고 있음을 밝히는 데 의의를 갖는다.

우리나라 농촌 인구의 고령화는 빠르게 진행되고 있으며, 2020년 기준 농업경영주의 평균 연령은 66.1세, 65세 이상 경영주 비율은 56%에 이른다. 2022년 기준 밭작물 전체의 기계화율은 63.3%인 반면, 정식 작업의 기계화율은 12.2%에 불과하며, 특히 고추 정식의 기계화율은 거의 0% 수준이다. 이러한 문제를 해결하기 위해 본 연구에서는 1회전 2식부 방식의 식부 메커니즘을 적용한 고추 정식기를 설계하였다. 식부 장치는 식부 프레임, 암(arm), 그리고 호퍼로 구성되며, 호퍼는 상사점에서 모종을 공급받아 하사점에서 식부한 후 모종과의 충돌 없이 복귀하도록 캠 메커니즘과 스윙 구조의 보조를 받는다. 호퍼는 하강 시 시계 방향의 반원 궤적을 따라 이동하고, 상승 시에는 타원 궤적으로 이동하며, 이때 상승 궤적은 사이클로이드 곡선과 높은 유사성을 보였고 주행속도가 증가할수록 그 유사성이 더욱 증가하였다. 재배 환경에 따른 주행속도는 하우스 재배에서 2.0 km/h(55.6 rpm), 노지 일반 재배에서 2.5 km/h(52.1 rpm), 노지 터널 재배에서 3.0 km/h(50.0 rpm)로 설정하였다. 식부 암의 회전속도를 60 rpm으로 고정한 조건에서, 주간거리별 최대 주행속도를 산출하였다. 주행속도와 주간거리가 증가할수록 식부 호퍼의 후퇴 면적은 감소하는 경향을 보였으며, 노지 터널 재배 조건(주간거리 500 mm, 주행속도 3.6 km/h)에서 가장 작은 후퇴 면적(10,560.0 mm²)이 나타났다. 본 연구는 1구 2식부 방식의 식부 메커니즘이 우수한 작동 성능을 가짐을 입증하였으며, 고추 정식기의 구조 및 구동 시스템 최적화를 위한 궤적 및 운전 조건 설정에 기초 자료를 제공한다.

This study aims to identify instructional design elements for flipped learning in Korean language education targeting foreign learners. A total of 61 studies published between 2014 and 2024 on flipped learning classes for foreigners were analyzed. The extracted instructional design elements were reviewed and validated by experts. The structure of flipped learning classes was categorized into three main stages—pre-class, in-class, and post-class—and further subdivided into six phases: presentation, practice, introduction, activity, evaluation, and reinforcement. For each phase, specific instructional materials, teaching strategies, and the roles of instructors and learners were defined. Based on expert feedback, the final elements were refined to reflect adjustments such as proficiency-based difficulty levels, the use of authentic language resources, clearer d escriptions o f activity t ypes, a nd appropriate limitations on group size. Through this process, this study derived and validated instructional design elements for flipped learning-based Korean language instruction, highlighting their relevance and practical significance for instructional design research.

This study aims to develop an underground expressway design for an exit area to mitigate traffic congestion. Thus, we explain the necessity of underground expressways and three reasons for persistent congestion on underground expressways despite an increase in supply. We focus on the first reason, which is a complicated traffic-flow conflict in the exit area, and analyze the traffic flow based on various conditions, such as the exit rate to a nearby interchange and the exit location for underground and ground roads. Consequently, we identify three factors that affect congestion in the exit area. The first factor is the exit rate, where a higher exit rate corresponds to a more severe congestion. The second is the exit location of two roads. When the exit of a road that exhibits a higher exit rate is placed on a curb side, the average delay is reduced. The final factor is the length of the lane-change section, where a longer lane-change section correspond to less congestion. However, after a certain length, the change in congestion is negligible. Based on these results, we suggest revised design guidelines for underground expressways in terms of exit location and the length of lane-change sections.

This study presents the design and FPGA implementation of a low-power, high-throughput digital modem for Medical Implant Communication System (MICS) applications. The proposed system applies a π /4-D8PSSK modulation technique to achieve high data efficiency while maintaining low power consumption. Implemented on a Xilinx Spartan-7 FPGA, the modem achieves a data rate of 16.4 ± 0.3 Mbps, with a power consumption of 0.6 ± 0.02 W/h, demonstrating a 40% improvement in energy efficiency compared to conventional 4FSK systems. The system satisfies IEEE 802.15.6 and ITU-R RS.1346 standards, with verified waveforms through MATLAB–Simulink and Chipscope. This work contributes to localization of medical implant communication technologies and provides a foundation for ASIC-based integration for next-generation biomedical and industrial wireless systems.

The purpose of this study is to develop and implement a customized AI-based speaking diagnosis, learning, and assessment system, SpeakMaster, in order to overcome the lack of systematic evaluation and practice opportunities in school English speaking class. This system integrates automated speaking scoring to provide students with feedback on their speaking abilities across pronunciation, conversation, and presentation. This study adopts a design-based research methodology, demonstrating the development and implementation process. 1,451 students and eight teachers in elementary, middle, and high schools participated in the experiment. Data were collected through learning logs, teacher journals, interviews, and post-surveys. The findings indicate that the system design is appropriate for English class, promoting students’ flow in engaging speaking practice. Students showed motivation and satisfaction while teachers found the system valuable for monitoring student progress and facilitating speaking assessments. Despite the challenges of improving chatbot performance and enhancing scoring reliability, the results suggest that SpeakMaster shows potential to enhance English speaking education.

This study develops and evaluates a prompt-driven large language model (LLM) agent for section design of doubly reinforced concrete (RC) beams. Using Google Gemini (Gems), an engineering “expert” that operates without fine-tuning by uploading ACI-318 provisions, sample design documents, and a database of prior beam designs was developed. The agent interprets code clauses, formulas, and constraints from these materials and retrieves similar design cases to propose an initial solution. It then incorporates user-specified natural-language constraints—most notably a strength-ratio cap (design strength ≤ 105% of required strength)—to iteratively refine toward safe and economical designs. Beyond reporting member size and reinforcement details, the agent provides step-by-step computational justifications for moment and shear checks, increasing verifiability and instructional value. We benchmark the LLM-generated designs against results from the commercial program MIDAS/Design+ and observe close agreement. In several scenarios, the constraint-guided LLM solutions are more material-efficient while remaining code-compliant. The workflow also supports batch processing from spreadsheet inputs, enabling practical automation across multiple beams. The approach requires no additional model training or coding making it accessible to non-developer practitioners. Results indicate that a general-purpose LLM, properly grounded with code documents and examples, can achieve practice-level performance with transparent reasoning. This demonstrates a viable approach to AI-assisted structural design that is explainable, interactive, and readily integrated with engineering workflows.

Enhancing the energy density of electrodes by increasing thickness and mass loading is a technological challenge. Thick electrodes suffer from severe deterioration in electrochemical performance due to insufficient structural integrity and sluggish charge transport, particularly under high current density. Herein, we fabricated thick LiFePO4 (LFP) electrodes with thicknesses ranging from 85.7 to 90.3 μm and an average mass loading of 17.68 mg/cm2 by tailoring the ratio of zero-dimensional (Super P, SP) and one-dimensional (multi-walled carbon nanotube, MWCNT) conductive additives. The electrodes containing MWCNT exhibited crack-free structure and enhanced electrochemical performance with increasing MWCNT ratio because of the superior mechanical properties and electrical conductivity of MWCNT. However, the electrochemical performance of the electrode containing only MWCNT deteriorated due to aggregation of the MWCNT and poor point to point contact with the LFP particles. The multi-dimensional conductive additives improve the dispersion of components within the electrode and the structural stability of the electrode. As a result, the tailored electrode exhibited a lower degree of electrode thickness expansion (1.4 %), lower polarization (60.8 mV at 0.1 C), excellent high-rate capability (132.7 mAh/g at 2 C), superior capacity retention (27.5 % at 3 C), and lower electrical resistivity and interfacial resistance (14.9 Ω cm and 3.8 Ω cm2, respectively) compared to other samples.