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.

The purpose of this study is to fabricate a multi-stage, variable-section and high-speed of the cutting device for recycling carbon fiber from waste hydrogen storage tanks. In this study, a high precision cutting device is fabricated utilizes (i.e., multi-stage, variable-section, high-speed cutting function and a diamond wire tool) to cut various waste hydrogen storage tank carbon fibers into scrap in a short period of time. The fabricated items include the development of diamond wire tools and wheels, cutting feed systems, structural frames, cooling system applications, and hydrogen tank fixing systems. The rotational speed of multi-stage wheel is in range of 0~600 rpm, and feed speed of diamond wire cutting tools is in range of 10–80 mm/min. The results showed that a new precision cutting device is able to cut the waste hydrogen storage tanks more than 400 pieces of performance indicator scrap (200×200 mm) within 8 hours of the cutting time. This confirmed that a new fabricated cutting device is a high speed cutting machine that is feasible for application in waste hydrogen storage tanks recycling in stead of conventional cutting device.

The purpose of this paper is to investigate the vibration phenomenon occurring in the structure such as a ship with the hemispherical substructure and operating at fixed frequency, and to suggest the active vibration control method using the Fx-LMS algorithm to reduce vibration amplification. In order to study the possibility of reducing vibration in the hemispherical structure, the active vibration control model was developed and a vibration control experimental device for the hemispherical structure was constructed. The narrowband Fx-LMS algorithm was developed to enable precise real-time control at a specific frequency, and the secondary path for dynamic control was modeled with two coefficients per frequency. The experimental device is equipped with three exciters, six 3-axis actuators, and six 3-axis error sensors, which can acquire 18 error sensor signals. Real-time secondary path tracking was possible with the secondary path consisting of two coefficients and the control algorithm, and effective vibration control performance was confirmed through this. And the experimental results of active vibration control of the exciter for three frequencies showed that the exciter vibration was reduced by a minimum of 63.7% and a maximum of 97.7%, which shows the possibility of reducing the vibration of the structure in real time using the proposed method.

In this study, structural analysis was performed to select the optimal design shape through failure identification and design changes in turbine housing. Damage in the inlet flange is considered to be high cycle fatigue due to the vibration excitation in the engine full load test. Therefore, the FE analyses were performed natural vibration analysis and frequency response analysis for the initial shape and design change models. The stress magnitudes were obtained as a function of frequency through frequency response analysis according to engine vibration excitation. As a result, the dynamic stiffness of Case (1) increased by approximately 3.6% compared to the initial model, and Case (2) increased by 4.6%. In addition, the stress magnitude was greatly reduced in the design improvement. Therefore, the model with only the flange thickness increased is thought to be optimal design for securing the durability of the turbine housing.

This study investigates the impact of solar paper panel tilt angles on the flight endurance of solar powered the drone. To address the limited flight time of conventional battery powered drones, photovoltaic solar paper panels were mounted at varying angles 0°, 15°, 30°, and 45° tested under consistent conditions. Experimental results showed that a 30° tilt angle produced the highest power output, leading to about 14% increase in flight duration compared to a flat configuration. These findings demonstrate that optimizing panel orientation significantly improves energy efficiency and drone performance. This work provides practical insight into the design of lightweight solar UAVs and highlights the feasibility of simple tilt adjustments as a low complexity alternative to active solar tracking systems.

Overloaded and improperly loaded trucks cause serious road hazards, such as rollovers and cargo falls. Although automatic enforcement methods are being studied, they face challenges in accuracy and legal application. Thus, a technology for direct tracking and enforcement is needed. This study uses EfficientNet to extract features of vehicles and license plates, and applies cosine similarity to identify the same vehicle. Comparisons were divided into “same vehicle” and “similar vehicle,” with a threshold-based method and five classification types. Results showed that the average similarity of the same vehicle group was 0.11 higher than that of the similar vehicle group. The accuracy of correctly identifying the same vehicle was 84.54%. Integrating OCR or LPR is expected to further improve tracking performance.

This paper reviews ordinal decision tree algorithms for ordinal classification, exploring theoretical foundations, key algorithms (MDT, QMDT), specialized splitting criteria (Ordinal Gini, Weighted Information Gain), and ensemble methods. It discusses applications in healthcare and social sciences, highlighting interpretability and flexibility while acknowledging overfitting and instability. As implications for future research, this study points out advantages such as interpretability and flexibility, and limitations such as overfitting and instability.

In this study, static and dynamic analysis verification was performed to apply the fuel cell system to the E-PTO of the Wire aerial vehicle. First, structural analysis was performed to improve the weak points that occurred. Next, vibration analysis was performed on the fuel cell system for which structural safety review was completed according to the wide-band irregular vibration test standard. The analysis results showed that resonance occurred in a specific frequency band and local stress was high, so stiffness reinforcement was performed. After reinforcing the stiffness, stress was reduced through a decrease in transient response characteristics and resonance phenomenon.

Bayesian techniques are vital in mechanical manufacturing for uncertainty quantification and process optimization. This review explores their diverse applications, highlighting advantages in handling small data and incorporating expertise for improved decision-making in quality control, reliability, and machining. It also discusses integration with machine learning and applications in specialized areas. Future research should focus on Industry 4.0 integration and user-friendly tools, emphasizing Bayesian methods' role in intelligent manufacturing.

This study aimed to improve safety and reduce labor intensity in offshore crab pot fisheries through the development of six types of automated fishing gear: a bait cutter, bait crusher, mainline arranging device, automatic pot hauler, cold water tank system, and crab pot unloading device. Sea trials demonstrated that both the bait cutter and bait crusher effectively reduced overall operation time. The mainline arranging device lowered the risk of injury compared to the conventional manual handling. The automatic pot hauler enabled the automated separation of crab pots, significantly decreasing the physical workload. The cold water tank system facilitated the efficient sorting of live crabs while enhancing onboard safety. Additionally, the crab pot unloading device reduced physical strain on workers and minimized catch damage. A satisfaction survey revealed high levels of approval among fishers, particularly regarding labor reduction and improved safety. Economic analysis indicated that vessels equipped with the automated gear experienced reduced overall operating costs. These findings suggest that the developed technologies will contribute to the long-term sustainability and modernization of offshore crab pot fisheries.

하수처리장 유출수의 수질 예측은 수질 사고의 사전 대응 및 처리장의 안정적인 운영을 위해 필수적인 요소이다. 최근 머신러닝을 활용한 예측 모델링에서 예측 성능 향상과 과적합 방지를 위해 다양한 교차 검증법과 하이퍼파라미터 최적화 기법이 활용되고 있으나, 하수처리장 데이터는 시간적 의존성과 급격한 변동성이 내재되어 있어 과적합에 취약하고 안정적인 모델 구축에 어려움이 따른다. 본 연구에서는 이러한 데이터 특성을 효과적으로 반영할 수 있는 최적의 모델링 파이프라인을 구축하고자 하였으며, XGBoost 모델을 기반으로 유출수 내 총질소 농도를 예측하였다. 예측 성능 평가 지표로는 평균 제곱근 오차(Root Mean Square Error, RMSE), 결정계수(coefficient of determination, R2), RMSE 오차 개선율(the rate of improvement on RMSE, RIRRMSE) 그리고 계산 시간을 사용하였다. 기본적인 Hold-out 방식의 성능을 기준으로 K-fold, 시계열 교차 검증(Time Series Cross Validation, TSCV), 블록 시계열 교차 검증(Blocked Time Series Cross Validation, BTSCV) 기법의 예측 성능을 분석한 결과, BTSCV는 인접한 데이터만을 고려하는 방식으로 시간적 의존성과 급변 특성을 효과적으로 반영하여 가장 높은 RIR(36.37%)을 기록하였다. 또한, 하이퍼파라미터 최적화(그리드 서치와 베이지안 최적화) 기법과의 다양한 교차 검증법의 조합을 통해 모델 성능과 과적합 방지 효과를 분석한 결과, BTSCV와 베이지안 최적화의 결합은 짧은 계산 시간(364.64초)과 함께 가장 높은 RIR(64.93%)을 보였으며, 훈련 및 평가 데이터 간 성능 차이도 최소화되어 일반화된 예측 모델로서의 효과성이 입증되었다. 따라서 본 연구는 하수처리장 시계열 데이터의 특성에 적합한 BTSCV와 베이지안 최적화 기법을 결합한 모델링 파이프라인 전략을 제안하며, 향후 실시간 수질 모니터링 및 하수처리장 운영 효율성 제고에 기여할 수 있을 것으로 기대된다.

Current portable reference equipment used to evaluate the performance of vehicle detectors can collect traffic volume and speed only for the outermost lanes in each direction. Passing vehicles on the other lanes are manually counted by reviewing the recorded videos. Consequently, only traffic volume—without vehicle speed—is used as a reference value. This method is time-consuming for comparing the performance data from the equipment with the reference data and can compromise the performance evaluation. This study aims to enhance the efficiency of vehicle detection system (VDS) performance evaluations by developing multilane portable reference equipment that can accurately collect traffic information for lanes beyond the outermost lane or for more than two lanes. This study introduced the core technologies of multilane portable reference equipment and compared and analyzed the measurement accuracy of the developed equipment against data from fixed reference equipment operated by the Intelligent Transportation System (ITS) Certification and Performance Evaluation Center, following ITS performance evaluation criteria. The data from the fixed reference equipment were considered the true values, providing a basis for evaluating the accuracy of the measurements by the developed equipment. First, the accuracy of the vehicle length was determined by driving four test vehicles, each measuring 7,085 mm in length, 24–29 times in each lane. The accuracy was calculated by comparing the vehicle length data obtained from the fixed reference equipment with the actual vehicle length. A confidence interval was established for this accuracy. To assess the accuracy of the speed and occupancy time in relation to the accuracy of the analyzed vehicle length, we evaluated the error range of the vehicle length according to variations in speed and occupancy time. This analysis was based on the following relationship equation: “vehicle length = speed × occupied time – sensor spacing.” The analysis used data from approximately 16,000 vehicles, including the speed, occupancy time, and vehicle length, collected between 8:00 am and 12:00 pm on August 8, 2024. The principle behind measuring traffic volume and vehicle speed using multilane portable reference equipment involves detecting a vehicle by analyzing the time difference between the driver and passenger tires. The vehicle speed was calculated using the installation angle of the tire detection sensor and trigonometric functions. An analysis of the measurement accuracy revealed that the traffic volume accuracy of the outermost lane (the fourth lane) was 100% during both day and night. The speed accuracy was 98.8% during the day and 97.7% at night, representing the highest performance in these metrics. Additionally, the traffic volume accuracy for the innermost lane (the first lane), as measured by the detection sensor from the third lane, was more than 99.3% at all times, with a speed accuracy exceeding 96% during the day and night, that also demonstrated excellent results. The analysis results indicated that the multilane portable reference equipment developed in this study was suitable for evaluating the VDS performance. This equipment allowed the collection of traffic volume and speed data from all lanes, rather than only the outermost lanes. This capability enabled consistent analysis for each lane and enhanced efficiency by reducing the analysis time. Additionally, this is expected to improve the reliability of the performance evaluations.

본 연구는 UN의 지속가능발전 세 번째 목표가 주창하는 ‘모두의 건강 한 삶 보장(Healthy life for all)’의 관점에서 미국 연방 및 주정부의 청 년 건강정책 사례와 실태를 분석하고 한국과 국제사회에 주는 정책적 시 사점을 도출하고자 하였다. 이를 위해 미국의 ACA, Healthy People 2030, WSCC 사례를 중심으로 정책 구조와 성과를 고찰한 결과 청년층 의 건강을 생애주기적 관점에서 통합적으로 관리하고 예방하는 체계를 확인할 수 있었다. 아울러 미국 청년 건강정책의 주요 대상인 12세-17세 와 18-34세 두 연령집단의 건강권 보장(무보험자 비율)과 정신건강(우울 감 또는 불안정서 지속 경험자 비율)의 추이를 파악하기 위해 미국 질병 관리본부(NHIS)의 최근 4개년 자료(2019년~2023년)와 아동가족통계포럼 의 최근 17개년 자료(2004-2021년)를 시계열 분석하였다. 분석 결과, 무 보험자 비율은 전반적으로 감소 추세를 보인 반면 2020년 이후 우울감 을 겪고 있는 청소년과 불안증을 겪는 청년층의 비율은 급격히 증가하여 코로나19 이후 청년층의 정신건강 악화 가능성을 시사하였다. 전술한 결 과로부터 본 연구는 한국 사회 또한 건강과 웰빙을 포괄하는 방향으로 청년정책 설계 및 방향을 전환해야 할 당위성을 논의하였다. 나아가 국 제사회가 주창하는 건강권 보장의 차원에서 청소년기부터 시작되는 누적 적 불이익을 사전 예방하기 위한 제도적 개입과 증거기반 정책수립의 필 요성을 촉구하였다.

다상 유도 전동기는 전력 변환 효율이 높은 전동기이다. 이와 같은 고효율 전동 기는 다양한 산업의 전기 수요가 증가하면서 더 필요한 상황이다. 이러한 상황에서 기업이나 국가가 적절한 전략을 세우기 위해 다상 유도 전동기 기술의 현 위치 확인과 미래 예측이 필 요하다. 다상 유도 전동기의 현 위치 파악과 미래 기술을 탐색하기 위해, 본 연구는 특허 네 트워크 경로 분석을 1902년부터 2024년까지의 특허 중 기술분류명(CPC H02K17/12 : 다상 비동기 유도전동기)에 적용한다. 그 결과, 미국과 유럽 기업이 전반적인 기술 개발을 주도하 였으며, 2010년 이후 중국 기업이 기술 개발을 급격히 늘렸음을 확인하였다. 네트워크 군집 분석 결과, 기계적 구조 개선 기술(전기 권선 및 극수 변환), 전기적 연결 기술(전류 파형 및 순서 변경), 스마트 융합 기술(센서+전기제어+전동기 구조 개선)의 세 가지 군집이 확인되었 다. 핵심 기술 경로 분석 결과, 일반적으로 인식하는 경쟁 우위 기업과 실제 기술적 영향력이 있는 기업 간의 차이가 존재했다.

본 논문은 초대교회의 사도들이 복음을 다양한 수용자 집단에게 어떻게 번역하고 제시했는지를 분석하고, 이러한 ‘복음의 번역가능성(translatability)’이라는 신학적 원리를 현대 전도에 어떻게 적용할 수 있을지를 고찰한다. 먼저 앤드류 월스(Andrew Walls)의 성육신 원리와 라민 사네(Lamin Sanneh)의 번역신학, 유진 나이더(Eugene Nida)의 역동적 등가 번역을 바탕으로 복음의 문화 간 전달 가능성에 대한 이론적 기초를 확립한다. 이어서 신약성경에서 유대인에게는 ‘그리스도’, 헬라-이방인에게는 ‘퀴리오스, 로고스, 소피아’와 같은 개념으로 예수를 소개했던 사도들의 전도 전략을 분석한다. 마지막으로 이러한 성경적·신학적 원리를 오늘날 다음세대 전도에 적용하기 위한 실천적 전략을 네 가지로 제시한다: (1) 개념어 번역의 전략화, (2) 이야기 중심의 복음 서술, (3) 미디어사역의 적극적 활용, (4) 공동체 중심 전도. 본 연구는 복음의 본질은 변하지 않지만, 그 표현과 언어는 시대와 문화에 따라 번역되어야 한다는 점을 강조하며, 복음의 생명력은 곧 ‘다시 말해질 수 있는 능력’에 있음을 밝힐 것이다.

The mental health care system in Korea employs measures such as involuntary hospitalization and outpatient treatment orders for patients with severe mental illness. However, involuntary hospitalization places the burden of treatment and management entirely on families, while outpatient treatment orders are often ineffective. This study proposes two approaches to strengthen national responsibility for these patients. First, a judicial hospitalization system is recommended to protect patient rights and ensure fair hospitalization and treatment. This system would provide appropriate care for patients while reducing the caregiving burden on families. Second, a nationally-centered integrated management system is proposed to connect medical institutions with community mental health agencies, for the integrated management of patients with severe mental illness. This system would ensure treatment continuity and enable efficient rehabilitation management. These proposals aim to create a foundation for patients with severe mental illness to reintegrate smoothly into society within a national management framework.

The aim of this study is to enhance understanding of government and association-led fashion support programs through in-depth interviews with program managers, identifying areas for improvement. A phenomenological approach, which explores the essence of a particular phenomenon as it manifests in human life to obtain an in-depth understanding of how individuals who have experienced the phenomenon perceive it and its meanings, is adopted. Evaluation criteria for receipt of supports included qualitative factors such as design, branding, product viability, market potential, and completeness, assessed by a panel of academics, buyers, stylists, media critics, distribution experts, press personnel, and designers. Some support programs provided stage-specific assistance based on revenue or business duration, while others required brands at vastly different stages—for example, in their fifth year or over twenty years since launch-to compete within the same program. Challenges faced by designer brands included limited budgets, timing constraints, poor inter-agency communication, and administrative burdens. Suggested improvements involved engaging fashion industry experts in policy planning, integrating export data from overseas production, simplifying documentation, revising regulations, fostering cross-industry collaboration, and establishing fashion venture funds to support competitive brands and accelerate growth. Future plans include expanding support through cultural content and material innovation to boost global recognition of Korean fashion brands. Findings indicate that strategies for vitalizing emerging Korean fashion designers include cross-industry collaboration, expert-led policy development, securing specialized investment funds, and elevating Seoul Fashion Week’s significance as a global platform to increase brand visibility and facilitate domestic and international orders.

This study explores the operational challenges of emerging fashion designers in South Korea through in-depth interviews. The findings reveal significant challenges across key components of brand operation: product and image development, production, sales, promotion, and finance. Designers sought to express original narratives through their collections each season but encounter significant obstacles, such as limited production capacity, lack of marketing resources, and financial instability. Small order volumes hinder securing manufacturers, forcing designers to reinvest most revenue into sample development, with little left for labor or growth. Based on these insights, the study proposes three strategies to strengthen designer brand growth. First, it is necessary to ensure the efficient operation of numerous institutions and associations in Korea through systematic and continuous support at each stage of their programs. Each institution and association should independently run their own separate support programs to improve their expertise, optimizing the government’s limited budget. Second, adopting an agency model for emerging fashion designers, similar to entertainment agencies, can be effective. In this model, agency-affiliated celebrities act as muses for clothing lines and merchandise, enhancing sales via strategic promotion and marketing while encouraging mutual growth through revenue sharing. Third, the Korean fashion designer industry’s distribution structure needs reform.

대서’ 마늘(Allium sativum L.)의 생장점 배양에 가장 효과적인 배양조건을 확립하고자 신초 유도 및 구 형성에 있어 식물생장조절제와 sucrose 농도의 영향을 조사하였다. 신초 유도에 관한 1차 시험에서는 NAA 0, 0.2, 0.5, 1 mg/L와 2iP 0, 2, 3, 5 mg/L를 조합하여 16가지 조건으로 설정하여 총 1,460개의 생장점을 처리하였다. 그 결과, NAA 0.2 mg/L에 2iP 2~5 mg/L를 처리한 조건과 NAA 1.0 mg/L에 2iP 5 mg/L를 처리한 조건에서 양호한 분얼 생성이 확인되었다. 특히, NAA 0.2 mg/L와 2iP 3 mg/L 처리군은 통계적으로 유의하지는 않았으나 가장 높은 평균 신초 생성률을 보여 효과적인 경향을 나타냈다. Sucrose 처리농도에 따른 기내소구 형성률을 비교하기 위한 2차 시험에서는 1차 시험에서 선발된 조건(NAA 0.2 mg/L, 2iP 3 mg/L)에서 배양한 1,193개의 생장점 중 생존한 546개를 5%, 7%, 9% 농도로 처리한 구 형성 배지에 계대배양하였다. 그 결과, sucrose 농도가 높을수록 기내소구의 형성률 및 0.1 g 이상의 큰 기내소구의 비율이 증가하는 경향을 보였으나, 통계적 유의성은 확인되지 않았다. 이상의 결과를 종합하면, ‘대서’ 마늘 생장점 배양에 적합한 신초 유도 조건은 NAA 0.2 mg/L와 2iP 3 mg/L의 조합이며, 구 형성은 9% sucrose 농도가 가장 효과적일 것으로 판단된다.

본 연구는 조선업 중심 산업도시 거제시의 위기 대응 거버넌스를 분석하며, 형식적 제도의 이면에 존재하는 이해관계자 배제의 구조적 문제와 불공정한 위 험 전가가 어떻게 지역의 회복과 전환을 가로막았는지를 규명하는 데 목적이 있 다. Morrison(2014)의 지표를 활용하여, 대기업 중심의 종속적 산업구조와 하청 으로 위험이 전가되는 이중적 고용구조 속에서 정책들이 어떻게 파편화되고 시 너지를 잃었는지 진단했다. 분석 결과, 공식적인 협의체는 핵심 이해관계자를 배 제한 채 형식적으로만 운영되었고, 정책 수단들은 현장의 불공정한 고용구조를 외면한 채 단기 처방에 머물렀다. 이에 본 연구는 효과적인 산업 전환을 위해서 는 분절된 정책의 양적 투입을 넘어, 노동 현장의 구조적 불공정을 해결하고 모 든 주체의 신뢰를 확보할 수 있는 통합적 거버넌스의 제도화가 구조적 전환을 위한 핵심 조건임을 실증 분석을 통해 확인하였다.