This study was conducted to improve the stability of small barges used for remote bird monitoring at Capsosiphon fulvescens aquaculture farms. The monitoring accuracy is compromised by rolling and pitching motions induced by waves and wind. To address this problem, a damping system was developed to enhance barge stability. Field experiments were conducted at a farm to evaluate the effectiveness of the developed damping system. The rotational motions of the barge, with and without the damping system, were measured using a six-axis gyroscope sensor. The measurements were conducted at the Capsosiphon fulvescens farm located in Cheokchan-ri and Deokdong-ri, Gogeum-myeon, Wando-gun, Jeollanam-do across two periods: from October 5, 2024 to December 17, 2024 (Damping without) and from February 19, 2025 to April 15, 2025 (Damping with). The collected data were validated against wind speed records from the Korea Meteorological Administration. The results demonstrated that the damping system effectively reduced barge motion. Within a wind speed range of 0.1-9.0 m/s, the system achieved an average reduction of 7.11% in rotational motions. Its maximum performance was recorded at approximately 7.0 m/s wind speed where it achieved a reduction of 23.35%. These findings confirm the system significantly enhances barge stability and improves monitoring reliability.

Pipe organs are an important element of acoustic performance and usage of concert hall, considered as one of indicators of classical music hall. However, only limited numbers are installed or planned for local concert halls. Therefore, in order to investigate the influence of the pipe organ to the concert hall and compare with variable acoustic equipment, acoustic parameters were measured and evaluated in conditions without the pipe organ and after installation. Moreover, acoustic parameters according to acoustic variable equipment were measured and evaluated to figure out an impact on acoustic performance. The result indicates that differences of parameters according to the presence of the pipe organ were, 0.66 sec in reverberation time (RT), 0.1 in bass ratio (BR), 0.66 sec in early decay time(EDT), 2.18dB in clarity (C80), 0.12dB in strength(G), and 0.16 in lateral energy fraction(LFC). Differences of acoustic parameters due to acoustic variable equipment were 0.86 sec in reverberation time(RT), 0.09 in bass ratio(BR), 0.78 sec in early decay time(EDT), 0.64dB in clarity(C80) and 2.34dB in strength(G).

본 연구에서는 어린이집 급식실에 설치된 냉장고, 냉동 고, 자외선 살균기 손잡이의 미생물 오염도를 조사하고 위 생 관리 방안을 제시하고자 하였다. 실험에 사용된 손잡 이는 전라남도 소재 어린이집 101곳의 냉장고, 냉동고, 자 외선 살균기를 대상으로 하였다. 냉장고, 냉동고, 자외선 살균기 손잡이의 일반세균 오염도는 평균 1 .9 ±0.9 log CFU/ 100 cm2, 1.9±0.7 log CFU/100 cm2, 2.0±1.1 log CFU/100 cm2로 나타났으며, 자외선 살균기의 오염도가 가장 높게 나타났다. 즉각적인 안전 조치가 필요한 급식 설비 손잡 이 수는 가정 4건, 국공립 6건, 민간 7건으로 민간 어린이 집 급식 설비 손잡이에서 일반세균수 오염에 가장 취약하 였다. 냉장고, 냉동고, 자외선 살균기의 대장균군 오염도 는 평균 1.4±1.4 log CFU/100 cm2, 1.1±1.1 log CFU/100 cm2, 1.1±1.0 log CFU/100 cm2로 나타나 냉장고의 오염도 가 가장 높게 나타났다. 보육시설 별로는 지역아동센터, 가정, 국공립, 민간 어린이집 순으로 높게 나타났다. 즉각 적인 안전 조치가 필요한 급식 설비 손잡이 수는 지역 아 동 0건, 가정 2건, 국공립 5건, 민간 10건으로 민간 어린이집 급식 설비 손잡이에서 대장균군 수 오염에 가장 취 약하였다. 어린이집 급식실 설비 손잡이의 살균 기준을 제 시하고자 대장균 저감화 효과를 실험하였다. 소독 티슈와 70% 에탄올을 이용하여 실험한 결과, 어린이집 급식실 설 비 손잡이를 살균할 시 소독 티슈를 새것으로 바꾸어 총 3회 살균하는 방법과 70% 에탄올 4회 분무 후 5분 건조 하는 방법이 가장 적합한 방법으로 나타났다. 이러한 결 과를 종합하여 볼 때, 어린이집 급식실 설비 손잡이에 의 한 교차오염을 예방하기 위하여 설비 손잡이를 소독 티슈 새것으로 교체하며 총 3회 이상 살균하거나, 70% 에탄올 4회 이상 분무 후 자연 건조하는 방법을 활용하여야 할 것으로 판단되었다.

The semiconductor equipment industry is characterized by high technological intensity and a strong demand for customized functionality from client firms. This necessitates the collection and implementation of diverse client requirements, which in turn demands close cross-departmental collaboration and leads to highly complex project structures. To manage this complexity, many semiconductor-related companies operate global matrix organizations based on multiple reporting lines by region, function, and product. These structures entail intricate communication process and pose significant collaboration challenges. This study empirically investigates key factors influencing collaboration and project performance within global matrix organizations in the high-tech semiconductor equipment industry, applying the Technology-Organization-Environment (TOE) framework. The analysis identified significant effects of all examined factors on inter-organizational collaboration performance: three technological sub-factors (usability of communication tools, process standardization, and change management systems), two organizational sub-factors (clarity of roles and responsibilities, and robustness of information-sharing systems), and three environmental sub-factors (alignment of requirements, cultural understanding, and responsiveness to industry standards and regulations). Furthermore, the level of agile implementation was tested as a moderating variable in the relationships between TOE factors and collaboration performance. The results revealed significant moderating effects of agility in specific areas: the usability of communication tools and systematic change management (technological factors); information-sharing structure (organizational factor); and requirement alignment (environmental factor). These findings suggest that agile approaches do not operate as a single-factor solution but interact dynamically with various organizational conditions. By focusing on the underexplored dynamics of global matrix organizations in collaboration performance, this study provides a structured empirical analysis of their operational characteristics. Its theoretical contribution lies in offering an integrative perspective on technological, organizational, and environmental drivers of collaboration and project success, extending current research in high-tech project and organizational performance.

The world's largest diesel power plant listed in the Guinness Book of World Records is Jordan's Amman Asian power plant, which produces a total of 573 MW of electric power. It consists of 38 units of 15MW capacity, and KEPCO achieved high profitability through the power plant. If a large capacity of 50MW clsss is applied, it will be newly listed in the Guinness Book of World Records even if only 12 units are constructed. Therefore, large-scale overseas orders for diesel power plants that require large capacity are expected in the future. The purpose of this study is to derive a installation offset by performing the shaft alignment analysis for large capacity 50MW shaft system. As a result, the offset of shaft system for the 50MW diesel power generation equipment was successfully derived through the bearing influence assessment and introduction of arrangement slope for main engine bearings.

이 연구에서는 원전 시설물의 부지응답해석 및 지반-구조물 상호작용 해석 등 다양한 동적 문제에 효율적으로 활용할 수 있는 무작 위진동이론(random vibration thoery, RVT) 방법론을 사용하여 원전 구조물에 설치된 기기의 지진취약도 분석기법을 제안한다. RVT 에 기반한 해석기법은 입력지반운동의 시간이력을 직접적으로 필요로 하지 않기 때문에 우리나라와 같이 강진지진기록이 충분하지 않은 지역에서 유용한 방법이다. 입력지반운동의 파워스펙트럼밀도(power spectrum density, PSD) 함수를 사용하여 대상 지반-구조 물 상호작용계의 추계학적 지진응답해석을 수행하고, 구조물 내부에 설치된 기기의 유사가속도에 대한 PSD 함수를 산정한다. 이 PSD 함수에 무작위진동 첨두응답의 확률분포를 추정할 수 있는 첨두값 계수를 적용하여 기기 유사가속도의 첨두값, 즉 구조응답스 펙트럼의 누적분포함수를 추정하고, 기기의 고장 조건을 적용하여 기기 고장 확률과 취약도곡선을 산정한다. 제안한 RVT 방법론에 근거한 지진취약도 분석기법을 균질 반무한 경암 및 연암 지반에 놓인 원전 구조물에 설치된 기기에 적용하고, 응답이력 방법론에 의 한 결과와 비교하여 제안한 기법의 정확성을 검증한다.

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.

목적 : 본 연구는 안경 처방에 필요한 매개변수를 분석하여 정확하고 편안한 안경 처방을 위한 객관적 자료를 제시하는 것이다. 방법 : 20세 이상 성인 41명(남자: 28명, 여자: 13명)을 대상으로 사진, 트르뷰 아이, 안경자 및 스마트 센터링 장치 계측법을 이용하여 단안 동공 거리, 동공간거리, 광학중심점높이, 경사각, 안면각 및 정점간거리를 계측하고, 사진 계측법을 표준으로 정확도(오차)를 비교하였다. 또한, 오차 보정 식을 통하여 임상에서 적용하기 위한 보정 값 을 산출하였다. 결과 : 4가지 장비의 계측법을 비교했을 때 광학중심점높이와 경사각, 안면각 및 정점간거리는 유의한 차이가 있었다(p<0.050). 사진 계측법을 표준으로 한 보정 값에서 트르뷰 아이는 단안 동공 거리, 동공간거리, 광학중심점 높이, 경사각, 안면각 및 정점간거리의 상관계수가 높고 통계적으로 유의하였다(p<0.050). 안경자는 단안 동공 거 리, 동공간거리, 광학중심점높이 및 정점간거리는 상관계수가 높고 통계적으로 유의하였다(p<0.050). 스마트 센터 링 장치는 안면각에서 통계적으로 유의하였다(p<0.050). 보정 값에 대한 95% 신뢰구간은 단안 동공 거리에서 스마 트 센터링 장치가 좁은 범위와 적은 편차를 보였고, 다른 모든 매개변수는 트르뷰 아이에서 좁게 나타났고, 평균값 의 편차도 가장 적었다. 결론 : 4가지 측정 장비를 이용하여 안경 처방에 필요한 매개변수를 측정한 결과 측정 방법에 따라 차이가 있었 고, 임상에서 사진 측정값을 대신하여 적용할 수 있는 보정 값을 제시하였다.

In this study, an active vibration control experiment was conducted on a display manufacturing system weighing approximately 15 tons. Three pneumatic shakers were installed underneath the equipment to excite the entire structure at three different frequencies. On the top side of the equipment, four inertial-type electromagnetic actuators capable of generating forces in the x, y, and z directions were mounted, enabling 12 degrees of freedom to be controlled. At locations near the actuators, four tri-axial accelerometers were installed to obtain 12 error signals. Vibrations at three distinct frequencies induced by the pneumatic shakers were measured at these 12 locations using the accelerometers. Active vibration control was performed by driving the inertial actuators using a narrow-band Fx-LMS algorithm to reduce the measured error signals. As a result of the control, the vertical vibration at 24 Hz was successfully reduced by 10.95 dB.

This study examined the offshore eel trap fishing process using one year of fishing logs and fishermen’s insights to identify key operational challenges and propose equipment improvement for greater efficiency and safety. Conger eel catches varied significantly by season, depth, and temperature, peaking in winter at 85–90 m and 23°C. The western waters of Jeju Island were identified as a major fishing ground, with the highest catch recorded in November and the lowest in July, reflecting seasonal trends. Each fishing operation deployed about 10,000 traps, with an average loss of 38 traps, posing economic concerns. The process involved intensive manual labor in bait preparation, trap retrieval, catch separation, line loading, and unloading, leading to high physical demands and safety risks. To address these issues, the study proposed automation through the development of a line loading device, trap cleaning device, bait processing machine, and automatic catch separator. These innovations could reduce the labor force required by one to two workers per process, alleviate workloads, and enhance resource management. By integrating quantitative logbook analysis with field-based knowledge, this study offers practical value. Further research is recommended on automation development, cost-effectiveness, and field validation to support safer and more sustainable eel trap fisheries.

소재·부품·장비(소부장) 산업은 국가 제조업 경쟁력의 핵심 동력으로, 정부는 소부장 R&D 지원사업을 통해 소부장 산업 혁신을 유도하고 있다. 본 연구는 성향점수매칭 (PSM)과 이중차분법(DiD) 및 삼중차분법(DDD)을 활용하여 소부장 R&D 지원사업이 수혜 기업의 경제적·기술적·사회적 성과에 미친 영향을 분석하고, 소부장 전문기업 지정효과에 대한 실증적 분석을 수행하였다. 연구결과 소부장 R&D 지원은 기업의 경제적 성과 일부에서 부정 적인 영향을 보였으며 기술적·사회적 성과에서는 유의미한 효과가 미미하였다. 반면에 소부장 전문기업 지정 제도는 순이익증가율, 총자산수익률 등 일부 경제적 성과와 연구개발집중도, 연구개발비증가율 등 일부 기술적 성과에서 유의미한 효과를 보였다. 한편, 사회적 성과에서는 소부장 일반기업 및 전문기업 모두 유의미한 성과를 확인할 수 없었다. 본 연구는 소부장 R&D 지원사업의 효과 분석뿐만 아니라 소부장 전문기업 지정제도를 실증적으로 평가한 점 에서 기존 정책 연구와 차별성을 가진다. 본 연구의 결과를 통해 정책 입안자의 소부장 성과 관리체계 강화 필요성, 소부장 전문기업 지정제도에 대한 제도적 보완과 소부장 기업의 소부장 지원 정책에 대한 전략적 접근 필요성 등을 제시하였다.

The demand for automated diagnostic facilities has increased due to the rise in high-risk infectious diseases. However, small and medium-sized centers struggle to implement full automation because of limited resources. An integrated molecular diagnostics automation system addresses this issue by integrating small-scale automated facilities for each diagnostic process. Nonetheless, determining the optimal number of facilities and human resources remains challenging. This study proposes a methodology combining discrete event simulation and a genetic algorithm to optimize job-shop facility layout in the integrated molecular diagnostics automation system. A discrete event simulation model incorporates the number of facilities, processing times, and batch sizes for each step of the molecular diagnostics process. Genetic algorithm operations, such as tournament, crossover, and mutation, are applied to derive the optimal strategy for facility layout. The proposed methodology derives optimal facility layouts for various scenarios, minimizing costs while achieving the target production volume. This methodology can serve as a decision support tool when introducing job-shop production in the integrated molecular diagnostics automation system

By developing molds and facilities to horizontally mold the functional part of the dry-cast concrete block, We intend to develop molds and a series of facilities to horizontally mold the functional part of the dry-cast concrete block to increase production per cycle while maintaining existing production methods and major facilities. In order to do so, CAE analysis is first required to develop molds and facilities for horizontally molding the functional part of the drycast concrete block in the horizontal direction. The procedure will be carried out by reviewing the validity of boundary conditions and physical properties, 3D modeling, grid generation, construction of analysis models, model validity, analysis according to frequency changes, and analysis according to physical properties. First, through the comparison of two-point support, three-point support, and two-point and three-point support in the constraint conditions, We would like to compare it with the actual molded product in the horizontal direction.