This experiment was carried out to study the effect of elapsed time after air flow cutoff on the germination rate of Italian ryegrass seed with different moisture contents during natural drying on reclaimed land, Jangheung and Kimje of Korea from 2023 to 2024, respectively. Seeds with moisture contents of 15.3, 22.3 and 28.0% were placed in vinyl bag (30 × 40 cm) at storage thicknesses of 10, 15, and 20 cm, and air flow was cutoff for 48 h. Seed moisture content, seed temperature (℃) and germination rate were investigated at 12-h intervals. After 48 h of airflow cutoff during natural drying, seed moisture content did not significantly differ among storage thickness treatment (p>0.05). When Italian ryegrass seeds with moisture contents of 27~28% were stored under conditions with air flow cutoff at 15~20cm thickness for 48 h, the seed temperature reached up to 30℃ and the germination rate was excellent at around 70~80%.

이 연구는 다목적 선박(MPV)의 공기역학적 구조물 설계, 분석 및 향상을 통해 그린 워터 압력에 의한 구조적 안전을 보장하고, 탈탄소화 및 에너지 효율성에 이바지하는 방법을 기술하였다. 유한 요소 분석(FEA)을 통한 초기 평가에서 좌굴 발생에 대한 잠재적인 취약점 이 있음을 확인하였다. 이러한 문제를 해결하기 위해 보강재(Carling stiffener)와 두께 증가를 통하여 응력을 재분배하고 국부적인 좌굴 발생의 위험을 최소화하였다. 보강 후 분석 결과, 한국선급(KR)의 안전 기준인 항복 강도, 미국 선급(ABS) 좌굴 강도 및 노르웨이 표준(NORSOK) 변 위 기준을 모두 충족하는 것이 확인되었다. 결과적으로 고유치 좌굴 해석 결과가 안전 기준을 초과하고 최대 변위가 허용 한계 내에 있는 등 중요한 개선이 이루어졌다. 이러한 개선은 극한의 해양 조건에서 운영 신뢰성을 보장할 수 있다. 이 연구는 공기역학적 항력 감소와 구조적 안전성의 이중적인 이점을 강조하며, 국제 해사 기구(IMO)의 2050 탈탄소화 목표에 부합하는 연료 효율성 및 온실가스 배출 감소에 이바지할 수 있다. 연구 결과는 다양한 선박 유형에 걸쳐 항력 감소 기술을 확장하기 위한 기초 자료를 제공하며, 지속 가능하고 탄력적인 해양 운영을 위한 대안을 제시하였다. 향후 연구는 구조적 안전 평가를 가속할 수 있는 단순화된 모델링 기술 개발에 집중할 것이다.

This study analyzed IoT-based indoor air quality monitoring data in a cooking room at a high school in Seoul. As a result of measuring the type and concentration change of cooking fumes generated during roasting, frying, and stir-fry, each cooking method showed a different pattern. Some cooking fumes were observed high during the distribution process, not during cooking, and it is necessary to observe and control indoor air quality during the entire process of cooking, storage, and distribution as well as various elements of cooking fumes. Through these results, we propose the addition of an IoT-based real-time indoor air quality monitoring system and ventilation facilities linked to it.

The importance of indoor air quality has significantly increased after the COVID-19 pandemic. This study analyzed the energy consumption of a ventilation system based on various operating methods considering indoor and outdoor conditions. From March to May 2024, experiments were conducted on ventilation systems installed in a hospital in Incheon, comparing the experimental and control groups. The results showed that using the bypass mode in the experimental group reduced total energy consumption by 25.34% compared to the control group. Additionally, utilizing the air-cleaner mode further reduced energy use. This study demonstrates that optimal use of bypass and air-cleaner modes can enhance energy efficiency. Further research is needed to verify long-term applicability under diverse conditions.

The Indoor Air Quality Control Act aims to regulate indoor air quality (IAQ) to safeguard public health and promote a comfortable living environment. This law encompasses multi-use facilities, newly constructed residential complexes, and public transportation vehicles. The law also involves mandating air quality standards, conducting periodic measurements, and transparent public reporting of results. Over time, the Indoor Air Quality Control Act has expanded to enforce stricter controls on building materials and enhance radon mitigation measures. In doing so, it embodies the principles of the Environmental Policy Basic Act and is supported by other laws, policies, and systems related to air quality management. In line with these efforts, local governments have been implementing IAQ initiatives tailored to regional needs, including consulting services and financial support. However, challenges persist in harmonizing management across diverse facilities due to overlapping responsibilities among laws and government bodies. Future recommendations emphasize integrated strategies and enhanced inter-agency coordination to address these gaps effectively, ensuring healthier indoor environments for all stakeholders.

This review paper provides a comprehensive analysis of the measurement and distribution of microplastics in the atmosphere and their role in the adsorption and transport of organic and inorganic pollutants. Due to their small size, large surface area, and hydrophobic nature, microplastics can adsorb a wide range of pollutants, including volatile organic compounds (VOCs) and heavy metals. These pollutants, strongly bound to the surface of microplastics, can remain suspended in the atmosphere for extended periods, facilitating the widespread distribution of contaminants. Building on existing research, this paper systematically reviews the sampling, pretreatment, and analytical methodologies applied to study microplastics in the air. Furthermore, it examines the influence of environmental factors on the adsorption and desorption dynamics of pollutants associated with microplastics. Various studies indicate that microplastics can interact with pollutants such as heavy metals, organic compounds, and microorganisms to form complex contaminants. These complexes can be transported and redistributed across long distances in the atmosphere, amplifying their environmental and health impacts. This review highlights that microplastics are not merely a pollutant themselves but serve as a vehicle for the migration and dispersion of other contaminants. This dual role emphasizes the significant risks microplastics pose to public health and the environment, necessitating further research and effective mitigation strategies.

This study presents an integrated indoor air quality index (IAQI) algorithm aimed at enhancing the efficiency of indoor air quality management in diverse indoor environments. The proposed IAQI accounts for the combined effects of multiple pollutants, offering a more comprehensive approach than traditional concentrationbased methods. Findings from four exposure scenarios and probabilistic health risk assessments indicate that the IAQI can be tailored to reflect occupant characteristics and space usage, thereby providing improved protection for sensitive populations, such as newborns. The application of occupant-specific criteria led to reductions in pollutant concentrations and associated health risks compared to conventional standards. Furthermore, the IAQI incorporates correction factors and weighted adjustments, facilitating robust risk assessments in complex multi-pollutant contexts. By addressing the limitations of single-pollutant management, this approach supports the development of more effective strategies for indoor air quality control. The proposed algorithm holds significant potential for practical applications in indoor air quality management and policymaking. Future research should focus on validating its effectiveness across a wider range of indoor environments.

Indoor air quality is a critical factor affecting health and quality of life, especially in spaces frequently used by sensitive populations such as adolescents. This study assessed the impact of garden ball installations and electrochemical fertilizer applications on indoor air quality in two youth centers, Center S and Center W, located in Bucheon, South Korea. PM2.5, PM10, and CO2 concentrations were monitored and analyzed based on the presence of garden balls and the use of electrochemical fertilizers. The results showed that spaces with garden balls (w/ G.B.) had significantly lower PM2.5 and PM10 concentrations compared to offices and spaces without garden balls (w/o G.B.). In Center W, the presence of garden balls alone improved air quality, highlighting the potential of vertical greening as a sustainable solution. In Center S, the application of electrochemical fertilizers during the “after + period” (when both garden balls and electrochemical fertilizers were applied) further enhanced particulate matter reduction, demonstrating the fertilizers’ ability to amplify plants’ air-purifying effects. This study provides empirical evidence that garden balls are an eco-friendly option for indoor air quality management. Combining electrochemical fertilizers with garden balls shows promise for enhancing air quality, offering a practical model for multi-use facilities such as youth centers.

Oyster mushrooms were analyzed to confirm the effect of installing a convection fan on the uniformity of the environment inside the cultivation house, the quantity of fruiting bodies, and marketability for stable production. When using a convection fan, it was confirmed that the temperature, relative humidity, and CO2 concentration were maintained more uniformly than when not used.As for the characteristics of the fruiting bodies, the quantity per bottle was 177.3 g when using a convection fan, which was 17% higher than when not used, and the individual weight was 49% higher. In addition, the cap diameter, cap thickness, and stem thickness increased slightly in the convection fan treatment, and the stem length was shorter.

Aerial work platform truck is used in various ways depending on the surrounding environment, of city roads, farming areas, and industrial sites. Air flow, drag force and torque in surroundig the flow field of AWP have been analyzed with CFD method. The overall air flow rate decreases as the AWP passes and increases between the vehicle and the boom, at the boom connections, and at the bottom of the work platform. The drag force and torque on the boom, workspace, and the combined boom and workspace are largely affected by air flow velocity. The boom's drag and torque are approximately 2.2 and 1.3 times greater than those of the work platform, respectively. These predicted results can be widely applied as basic conceptual design data for highly efficient aerial work platform truck.

The Climate chamber system is an essential facility for aerodynamic performance development of commercial vehicles to investigate air flow field characteristics in different climatic conditions. In particular, the analysis of airflow fields within the chamber system is an essential consideration for optimal design. In this study, the pressure characteristics and velocity uniformity in the test section area were predicted with blower impeller rotational speed using CFD. The velocity uniformity is affected by the distance from the blower nozzle outlet, reaching up to 72.7% at 695 RPM. The pressure differential between 300 RPM and 740 RPM shows an approximate difference of 2651 Pa, with a high-pressure distribution observed along the right side wall of the blower. These results are expected to be used as design data applicable for improving the performance of environmental chamber systems.

Air flow field characteristics in a compact chamber system are indispensable for the efficient development of vehicle aerodynamic performance. In this study, air flow and velocity uniformity in the chamber system were numerically analyzed using the CFD method. Air flows at a uniform velocity from the outlet of the blower, passes fast through the heat exchanger with partial pressure difference, and then moves into the blower inlet. Overall pressure drop through the fan gradually increases with the flow rate. The uniformity varies along the test section, decreasing by 5-10% with distance from the nozzle. These predicted results can be widely used as basic conceptual design data for an efficient vehicle chamber system.

The objective of this study is to analyze the indoor air quality of multi-use facilities using an IoT-based monitoring and control system. Thise study aims to identify effective management strategies and propose policy improvements. This research focused on 50 multi-use facilities, including daycare centers, medical centers, and libraries. Data on PM10, PM2.5, CO2, temperature, and humidity were collected 24 hours a day from June 2019 to April 2020. The analysis included variations in indoor air quality by season, hour, and day of the week (including both weekdays and weekends). Additionally, ways to utilize IoT monitoring systems using big data were propsed. The reliability analysis of the IoT monitoring network showed an accuracy of 81.0% for PM10 and 76.1% for PM2.5. Indoor air quality varied significantly by season, with higher particulate matter levels in winter and spring, and slightly higher levels on weekends compared to weekdays. There was a positive correlation found between outdoor and indoor pollutant levels. Indoor air quality management in multi-use facilities requires season-specific strategies, particularly during the winter and spring. Furhtermore, enhanced management is necessary during weekends due to higher pollutant levels.