최근 기후 변화로 인해 기온 상승과 강수 특성의 변화가 가속화되면서 도로 포장의 장기 성능에 미치는 영향이 점차 중 요해지고 있다. 아스팔트 콘크리트 포장은 온도 및 수분 조건에 민감한 재료 특성을 가지므로 동일한 재료·구조·교통 조건에 서도 기후 조건에 따라 포장 거동과 수명이 크게 달라질 수 있다. 현재 MEPDG(Mechanistic-Empirical Pavement Design Guide) 프로그램은 EICM(Enhanced Integrated Climatic Model) 기후 모델을 통해 온도 및 수분 조건을 반영하여 공용기간 동 안의 포장 성능을 예측하는 성능 기반 설계 방법을 제공하고 있으나, 기후 입력은 과거 관측자료를 기반으로 생성된 정상성 기후 데이터에 의존하고 있다. 그러나 최근 평균기온 상승과 극한 기상 현상의 증가로 장기 기후 조건이 비정상성을 나타내 고 있으며, 이러한 변화는 포장 설계의 신뢰성에 영향을 미칠 가능성이 있다. 본 연구에서는 강릉 지역의 1965–2024년의 장 기 기온 시계열 자료를 대상으로 확장 디키–풀러(Augmented Dickey-Fuller, ADF) 검정과 크비아트코프스키–필립스–슈미트– 신(Kwiatkowski–Phillips–Schmidt–Shin, KPSS) 검정을 수행하여 정상성 여부를 진단하였다. 분석 결과 두 검정 모두 비정상 성이 우세하게 나타나 시계열 내에 장기 추세가 존재함을 확인하였다. 나아가, 미래 기후 변화를 반영하기 위하여 네 가지 기온 시나리오를 설정하였다. 과거 관측자료의 월별 평균을 기반으로 한 기준 시나리오와, 장기 기온 상승 추세를 반영하기 위한 회귀 분석 기반 시나리오를 구성하였다. 또한 IPCC(Intergovernmental Panel on Climate Change)에서 제시한 SSP(Shared Socioeconomic Pathways) 시나리오 중 중간 배출 경로(SSP2-4.5)와 고배출 경로(SSP5-8.5)를 적용하여 미래 기온 조건을 설정 하였다. 강수량, 상대습도, 풍속 및 일조율은 장기 추세가 뚜렷하지 않은 것으로 판단되어 과거 자료의 평균 패턴을 기반으 로 미래 데이터를 생성하였다. 구축된 기후 데이터는 MEPDG 입력 형식으로 변환되어 기후 변화 조건에 따른 포장 성능 평 가에 활용될 수 있으며, 비정상성 기후를 고려한 포장 설계 및 유지관리 전략 수립을 위한 기초 자료를 제공할 수 있을 것 으로 기대된다.
Tire noise is one of major causes of vehicle noise, and urban traffic noise pollution is becoming more and more serious as the number of vehicles continues to increase. Especially in the age of electric vehicles, improvement of tire noise is getting more important. Especially during highway driving, the noise from the tire became the main noise source of the vehicle. Tire noise is generated from the mutual friction between the tire and the road surface when driving. In this paper, we analyze various factors affecting tire noise generation, reduce environmental noise pollution, and increase ride comfort. The EU carried out the EC 1222/2009 tire labeling system in 2012, which was a severe blow to the tire exporting countries of all countries due to the stringent demand for tire noise. In this paper, 5 tires from 3 countries were selected and selected as test subjects. The purpose of this study is to analyze the noise of road / tire noise according to road condition of each tire.
배수 관망에서 가지관은 주 송수관에서 물을 주민에게 공급하는 핵심 요소이나, 일부는 불법적으로 사용되거나 정보가 불확실하여 관망 운영 효율을 저하시킨다. 본 연구는 단순 관망을 대상으로 천이류 해석과 실험을 통해 다중 가지관 탐지 기법을 검증하였다. 연구목적은 천이류 기반 가지관 탐색법의 적용 가능성을 평가하고, 관로 매개변수의 민감성을 분석하는 것이다. 개발된 방법은 단순 관로에서 전통적인 특성선 방법에 볼밸브의 비선형 거동 분석을 연계해 해석했다. 해석과 실험은 동일한 관망에서 두 개의 가지관을 대상으로 수행되었으며, 실험 내재 불확실성을 고려하였다. 두 분석 모두에서 구별 가능한 압력 신호가 확인되어 제안된 방법의 가지관 탐지 가능성을 입증하였다. 또한 결과는 불균일한 파속도와 일관되지 않은 천이류 유입 조건이 탐지 성능에 큰 영향을 미치는 것으로 나타났다.
The Stone Pagoda at Mireuksa Temple Site, Iksan, built during the reign of King Moo(武王) of Baekje(百濟), is one of the earliest stone pagodas in Korea. The main feature of the Stone Pagoda at Mireuksa Temple Site, Iksan is the technique of constructing the pagoda body using a technique of constructing stone structures that is difficult to find in China or Silla during the same period. In this study, we inferred that the origin of the Post & lintel construction technique of the stone pagoda of Mireuksaji Temple in Iksan came from the Post & lintel construction Stylobate of Baekje. As a result of comparing the part composition and joining method of the pagoda body and the Post & lintel construction stylobate, it was confirmed that the Post & lintel construction stylobate influenced the construction technique of the pagoda body. In addition, differences in the way the Post & linte construction technique is applied depending on the location of the pagoda body of Stone Pagoda at Mireuksa Temple Site, Iksan were inferred. This study is significant in that it clearly reveals the origin of the unique construction technique of the Stone Pagoda at Mireuksa Temple Site, Iksan.
Anomaly detection is crucial for ensuring the reliability and safety of mechanical systems across industries such as power generation, manufacturing, and transportation. In these mechanical systems, data is usually collected in time-series form using sensors such like vibration, current or sound for anomaly detection. Time-series anomaly detection methods often face limitations due to insufficient training data and poor generalization across complex operating conditions and varying loads. To address these challenges, this study proposes a transfer learning-based anomaly detection model, leveraging pre-trained knowledge to deliver robust performance and adaptability in data-scarce scenarios and diverse industrial environments. To this end, time-series signals are transformed into spectrograms through Short-Time Fourier Transform(STFT), followed by feature extraction through a Convolutional Autoencoder to obtain low-dimensional latent features. These features are used to detect anomalies using classification such as Random Forest and eXtreme Gradient Boosting. Building on this approach, this research validates the model's performance through migration tasks using the Case Western Reserve University(CWRU) Bearings dataset. Furthermore, to show cross-condition generalization, the proposed model was validated on the Hanoi University of Science and Technology(HUST), Sumair–Umar Bearing Fault(SUBF) dataset v2.0, and a dataset collected using microphone sensor in motor dynamo tests. Consequently, unlike other studies limited by specific operating conditions, the proposed model exhibits strong generalization performance across benchmark datasets. Experimental results highlight the effectiveness of combining STFT, CAE, and tree-based classifiers in addressing data scarcity and enhancing generalization, making it highly suitable for real-world industrial applications. Future work will focus on noise-robust techniques and broader fault types to further improve performance.
The molecular dynamic simulation method is usually used to analyse microscopic fluid fields. To use this method in engineering problems with real scales of molecules needs more time and greater computer power than we have now. To overcome these limitations, the expansion method using dimensionless and similarity of physical quantities of molecules is studied and introduced for the engineering scale fluid dynamics.
본 논문은 위진남북조 경사(經師) 음주(音注)를 정리하고 연구하는 과정에서 반절(反切) 비교 법이 지니는 여러 문제점을 대상으로 삼아, 반절 비교법의 한계를 탐구하고 선행 연구를 바탕으 로 저자의 견해를 밝혔다. 즉 반절 비교법을 운용할 때에는 직음(直音), 이문참증(異文參證) 등의 방법을 결합해 사용하고, 특수한 음주를 신중하게 처리함으로써 연구 결론의 신뢰성과 객관성을 확보해야 함을 강조했다. 또한 학계의 기존 연구에서 경전석문(經典釋文)의 ‘수음 (首音)’, ‘중가별독(衆家別讀)’, ‘혹음(或音)’, ‘일음(一音)’ 등 개념에 대해 종재하는 다양한 이 견과 상이한 해석에 의문을 제기하고 여러 이견을 변별했으며, 해당 문제를 합리적으로 해결할 수 있는 방안을 제시했다.
Recently, fire evacuation problems in high-rise buildings have been increasing due to increased occupant density and limited evacuation routes, leading to increased casualties. To address this issue, this study proposes a distributed evacuation performance evaluation method that considers floor-by-floor distribution ratios. Using FDS+EVAC-based simulations, various floor-by-floor distribution scenarios were designed and their impact on evacuation times and bottlenecks was quantitatively analyzed. The results confirmed that rationally adjusting the floor-by-floor exit and elevator utilization ratios shortened overall evacuation times and reduced congestion in specific areas. This method can serve as a foundation for establishing evacuation plans and fire safety design standards for high-rise buildings.
This study was conducted to evaluate the feasibility of applying a bending process as an alternative to the conventional welding method for rolled homogeneous armor(RHA) steel used in the turret structures of tanks. After analyzing the turret geometry and the mechanical characteristics of RHA steel, the upper and lower die profiles were optimized based on the MIL-DTL-12560 specification. Through forming simulations, the appropriate die opening width and punch stroke were derived. In particular, the final bending conditions were determined by accounting for springback effects. Structural analysis results confirmed that the maximum residual stress and total strain remained within the allowable mechanical limits of RHA steel, and the strain values approached the material’s elongation limit of approximately 15%, ensuring practical forming stability. This study presents a practical guideline for die design and bending conditions applicable to high-strength armor steels, and is expected to serve as a foundational reference for process optimization in the manufacturing of military vehicles and protective structures.
This study aimed to develop a powderization strategy using porcine by-products (kidney, liver, and heart) by evaluating the effects of raw material type, pretreatment, and additives (hydroxypropyl methyl cellulose P645 and gelatin) on powder characteristics. Powders from kidney tissue were analyzed for yield, particle structure, compressibility, and size distribution, based on the drying method and additive composition. The spray-dried sample with gelatin at 1:0.5 (w/w) showed 20.4% compressibility and the smallest, most uniform particles, indicating excellent flowability. Due to its superior structural stability, gelatin was selected over HPMC P645. Liver and heart samples that underwent enzymatic hydrolysis and the Maillard reaction were spray-dried with gelatin and assessed for yield and microstructure. The Alcalase-treated liver sample showed the highest yield. Surface analysis confirmed that gelatin formed a protective film enhancing particle stability. These findings suggest gelatin-based spray drying is effective for producing high-quality powders from protein-rich by-products.
Neighboring living facilities and commercial housing have increased along with the rapid expansion of the city. However, unlike general apartment complexes and planned cities, most buildings are built on a narrow site in neighborhood living facilities and commercial housing areas, so securing sidewalk blocks, which are pedestrian passages, is insufficient. The water supply fire hydrant installed in such a narrow sidewalk block has become an obstacle to pedestrian traffic. As a result of the survey, 62% of the walking passages in places where water supply fire hydrant (including protective frames) are installed in the sidewalk block were less than 1.5m. The "Rules on Road Structure and Facility Standards" stipulate that the minimum width of the sidewalk block is 2m or more, and the obstacles and effective width of passage are 1.5m or more. In addition, it was confirmed that the protective frame was interfering with the connection of the fire hydrant hose according to the media reports and the actual results of this study. Therefore, it is necessary to secure a space where the water supply fire hydrant can be used smoothly in case of fire and a safe walking passage, and to manufacture a protective frame, establish construction standards, and prepare legal and institutional standards for efficient maintenance.
This study presents a truck classification method using panoramic side-view images to meet the Ministry of Land, Infrastructure and Transport’s 12-category standard (types 4–12). The system captures a vehicle’s full side profile via a panoramic imaging device, ensuring complete wheel visibility. A YOLOv12-based deep learning model detects wheels, and image processing extracts their center coordinates. Pixel distances between adjacent wheels are calculated and normalized to determine axle spacing patterns, which, together with wheel count, are applied to a rule-based classifier. Tests on 1,200 real-world panoramic truck images (1,000 for training, 200 for testing) achieved a mean average precision of 96.1% for wheel detection and 90.5% overall classification accuracy. The method offers explainable classification through measurable structural features, supporting applications in smart tolling, road usage billing, overloading enforcement, and autonomous vehicle perception.
The K2 tank not only has excellent mobility but also has excellent protection performance. Armor steel is used to provide structural protection, and the turret structure is made of rolled homogeneous armor (RHA) plates. Most processes for fabricating structures involve welding, but RHA steel has the problem of being susceptible to thermal deformation. To compensate for this, a plan to apply the bending method was considered. In this study, prior to applying the bending method to an actual vehicle, mechanical property evaluations were performed on materials, welding, and bending specimens. It has been proven that the bending method can achieve performance equivalent to or better than the welding method. The verification tests included hardness tests, tensile tests, fatigue tests, and impact tests. All tests except the impact test confirmed that the bending method was superior to the welding method. In the case of the impact test, the impact value of the bending method was lower, but it satisfied the standard with a value higher than the minimum requirement according to the standard, so it is judged that there will be no problem in applying the bending method.
This study was carried out in a cold storage chamber with a floor space of roughly 3.3 square meters (1 pyeong). The findings revealed that the hybrid cooling system consumed a comparable amount of electricity to that of the conventional vapor compression system. This similarity in power usage can be attributed to the hybrid system’s operational strategy: thermoelectric modules were selectively activated during periods of frost accumulation, effectively minimizing the energy typically used for electric defrosting in vapor compression units. To advance the commercialization of this hybrid system in cold storage applications, several technical improvements must be considered in addition to cost optimization. First, the design should address the bulky nature of the heat exchanger setup. At present, the vapor compression and thermoelectric modules are housed in separate outdoor units; a more efficient approach would involve integrating them into a single, space-saving unit. Second, incorporating a water mist spray mechanism for the outdoor heat exchanger coil could enhance heat dissipation. This method, which leverages latent heat exchange, has demonstrated strong performance in other applications and merits further investigation for use in the proposed system.
본 연구는 북한이탈주민과 남한 주민의 사회통합을 위한 연구로써 연 구자는 통합적 문헌 고찰 방법으로 접근하여 사회통합에 기여할 수 있는 이론적 통찰과 방법론적 함의를 도출하고자 하는 목적에서 출발했다. 본 연구에서는 총 42편의 논문을 분석했다. 문헌 분석은 북한이탈주민의 법 적 지위와 법제 통합, 외국 사례의 분석과 시사점 연구, 대북지원과 통합 정책 평가와 방향 제시, 사회적 자본과 멘토링 연결망, 북한이탈주민의 동질성 회복 및 공생, 학교 적응과 교육, 차별과 취업 불만, 낙인, 문화 적응과 관계 형성, 소통과 심리적 통일, 포섭과 배제의 연구 문제로 나누 어 분석했다. 연구 결과에 근거하여 북한이탈주민들의 정치적 다양성, 주 체사상의 극복과 새로운 시민으로서의 정체성 재구성, 북한이탈주민들의 문화자본 등에 대한 연구의 필요성과 함께 제3국에 거주하고 있는 북한 이탈주민 여성 자녀들의 문제와 지지방안 수립에 관해 논의했다.