PURPOSES : This study aimed to compare the object detection performance based on various analysis methods using point-cloud data collected from LiDAR sensors with the goal of contributing to safer road environments. The findings of this study provide essential information that enables automated vehicles to accurately perceive their surroundings and effectively avoid potential hazards. Furthermore, they serve as a foundation for LiDAR sensor application to traffic monitoring, thereby enabling the collection and analysis of real-time traffic data in road environments. METHODS : Object detection was performed using models based on different point-cloud processing methods using the KITTI dataset, which consists of real-world driving environment data. The models included PointPillars for the voxel-based approach, PartA2-Net for the point-based approach, and PV-RCNN for the point+voxel-based approach. The performance of each model was compared using the mean average precision (mAP) metric. RESULTS : While all models exhibited a strong performance, PV-RCNN achieved the highest performance across easy, moderate, and hard difficulty levels. PV-RCNN outperformed the other models in bounding box (Bbox), bird’s eye view (BEV), and 3D object detection tasks. These results highlight PV-RCNN's ability to maintain a high performance across diverse driving environments by combining the efficiency of the voxel-based method with the precision of the point-based method. These findings provide foundational insights not only for automated vehicles but also for traffic detection, enabling the accurate detection of various objects in complex road environments. In urban settings, models such as PV-RCNN may be more suitable, whereas in situations requiring real-time processing efficiency, the voxelbased PointPillars model could be advantageous. These findings offer important insights into the model that is best suited for specific scenarios. CONCLUSIONS : The findings of this study aid enhance the safety and reliability of automated driving systems by enabling vehicles to perceive their surroundings accurately and avoid potential hazards at an early stage. Furthermore, the use of LiDAR sensors for traffic monitoring is expected to optimize traffic flow by collecting and analyzing real-time traffic data from road environments.
Among various organic materials suitable for silicon-based inorganic-organic hybrid solar cells, poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) has been extensively studied due to its high optical transmittance, high work function, and low bandgap characteristics. The electro-optical properties of PEDOT:PSS have a significant impact on the power conversion efficiency of silicon-organic hybrid solar cells. To enhance the photovoltaic properties of the silicon-organic hybrid solar cells, we developed a method to improve the properties of the PEDOT:PSS film using Ag nanowires (NW) instead of conventional solvent addition methods. The influence of the Ag NW on the electro-optical property of the PEDOT:PSS film and the photovoltaic performance of the silicon-organic hybrid solar cells were investigated. The addition of Ag NW further improved the sheet resistance of the PEDOT:PSS film, enhancing the performance of the silicon-organic hybrid solar cells. The present work using the low sheet resistance PEDOT:PSS layer paves the way to develop simple yet more efficient siliconorganic hybrid solar cells.
This study was conducted to simulate the lifetime of the membrane by analyzing the performance of the membrane degraded by chlorine. Chlorine exposure under several conditions caused the degradation of the membrane, resulting in the absence of any salts and an extreme increase in permeability. When the n value was calculated and compared through CnT analysis and CTn analysis, the p values were all less than 0.005, but CTn analysis, which had a higher R2 value, was adopted to simulate the membrane lifetime. Power coefficients take on values higher than 1, indicating that the exposure time to chlorine has a greater influence on membrane deterioration than the chlorine exposure concentration at 20℃ and 30℃. In particular, the process should be operated at less than 0.5 ppm at 30°C, and the chlorine exposure time of 1 cycle should be set to within 15 hours. In addition, the sensitivity to chlorine increased by 10.5 to 12.2 times when the chlorine exposure temperature increased by 10°C through the correlation between the chlorine exposure cycle and membrane lifetime. The membrane lifetime investigated in this study is only an estimated value, entirely because of chlorine membrane deterioration, excluding raw water characteristics and the type of detergent. Accordingly, it is considered that the membrane lifetime simulation can be applied by comparing the membrane performance with the actual process based on the filtration performance of membrane deterioration by chlorine.
본 연구에서는 서울 북부지역에서 유통된 1,737건의 농 산물을 대상으로 잔류농약 실태 조사 및 위해성 평가를 하였다. 분석 시료는 QuEChERS 법으로 전처리한 후 GCMS/ MS 및 LC-MS/MS를 이용하여 분석하였으며, 다빈도 부적합 성분을 대상으로 직선성과 정량한계, 회수율, 상대 표준편차(RSD%) 구한 결과 OECD 및 Codex의 기준에 적 합하였다. 또한 모니터링 결과 72품목 560건(32.2%)에서 잔류농약이 검출되었으며 22품목 38건(2.2%)이 잔류농약 허 용치를 초과하였다. 잔류농약이 많이 검출된 품목은 과일류 53.8%, 채소류 33.0%, 허브류 28.6%, 두류 15.4%, 곡류가 10.5% 순이였으며, 잔류농약 허용치를 초과한 품목은 채소 류 중 엽채류, 엽경채류, 근채류, 향신료 및 버섯 등이었다. 검출된 농약은 105종으로 그 중, dinotefuran, fluxametamide, chlorfenapyr, azoxystrobin, carbendazim이 가장 많이 검출되 었으며, terbufos, carbendazim, fluxametamide 등 23종의 성 분에서 잔류 허용기준이 초과되었다. 잔류허용기준을 초 과한 농약에 대해 위해 평가를 수행한 결과 위해 지수가 0.00003-1.31406%로 매우 낮은 수준으로 산출되어 안전한 것으로 평가되었다.
강원도 북부의 남북 접경지 3개소(서부-철원, 영서-양구, 영동-고성)에서 2023년 5월 11일부터 10월 12일까지 주요 천공성 해충 분류군인 나무좀아과를 대상으로 시기별 발생 양상 및 4가지 유인제(Ipsenol, Ipsedienol, Alpha-pinene, Monochamol)별 유인되는 종과 개체수를 조사 하였다. 연구결과, 총 26속 45종 7,743개체를 확인하였다. 확인한 종 중, 15종이 모든 조사지역에서 공통적으로 발생하고, 2종(암브로시아나무 좀, 왕녹나무좀)이 모든 조사지에서의 우점종으로 확인되었으며, 4종(오리나무좀, 붉은목나무좀, 여름나무좀, 암브로시아나무좀)이 조사기간(5 월~10월) 중 지속적으로 발생하는 것으로 확인되었다. 지역적으로는 가장 다양한 식물종들로 혼합림을 구성하고 있는 양구지역에서 총 36종 2,840개체가 확인되어 다른 두 조사지에서보다 다양하고 많은 개체가 확인되었다. 각 조사지에서 유인제별 확인한 종수는 유의미한 차이를 보이 지 않았으며 개체수면에서 철원에서는 Monochamol, 양구에서는 Ipsedienol, 고성에서는 Ipsenol 유인제에서 가장 많은 개체가 확인되었다.
This study was conducted to selection and investigate appropriate conditions for mass production of antagonistic microbes to control cobweb disease caused by Cladobotryum mycophilum. A grampositive bacterium was isolated from spent substrate of Agaricus bisporus and showed significant antagonistic activity against Cladobotryum mycophilum. The bacterium was identified as Bacillus altitudinis. based on the cultural, biochemical and physiological characteristics, and 16S rRNA sequence. The isolate is saprophytic, but not parasitic nor pathogenic to cultivated mushroom whereas it showed strong inhibitory effects against C. mycophilum cells in vitro. The control efficacy of B. altitudinis HC7 against cobweb disease of C. mycophilum was up to 78.2% on Agaricus bisporus. The suppressive bacterium may be useful for the development of biocontrol system. To define the appropriate conditions for the mass production of the Bacillus altitudinis HC7, we have investigated appropriate culture conditions and effects of various nutrient source on the bacterial growth. The appropriate initial pH and temperature were determined as pH 6.0 and 30oC, respectively. The appropriate concentration of medium elements for the growth of pathogen inhibitor bacterium(Bacillus altitudinis HC7) was determined as follows: 3.0% soluble startch, 10% soytone, 1.0% (NH4)2HPO4, 1.0 mmol KCl, and 0.5% L-asparagine.
The purpose of this study is to elucidate the impact of authenticity on experience value and subjective well-being among visitors who have participated in direct experiential activities in experiential fishing villages. The research method used literature research methods and empirical research methods using questionnaires, and this questionnaire was composed by determining three major variables and seven constituent factors for each variable through factor analysis and conducting prior research and preliminary surveys. The survey was conducted from February 5, 2023 to April 5, 2023 among experimental fishing villages with excellent ratings for scenery (environment), service, experience, accommodation, and food, and four villages that can experience tidal flats and manage customers online. The survey was conducted from February 5, 2023 to April 5, 2023, among experimental fishing villages with excellent ratings for scenery (environment), service, experience, accommodation, and food, and four villages that can experience tidal flats and manage customers online. The results of this study are as follows. First, the factors of authenticity in experiential fishing villages include three sub-factors: objective authenticity, constructive authenticity, and existential authenticity. The factors of experience value include two sub-factors: emotional values and functional values. Subjective well-being is derived from positive emotion and life satisfaction. Second, upon examining the importance of authenticity in experiential fishing villages, it was found that existential authenticity and objective authenticity, in that order, have a significant impact on emotional values. However, constructive authenticity did not have a significant impact on emotional values. Third, in terms of functional values, constructive authenticity, existential authenticity, and objective authenticity, in that order, had a significant impact. Fourth, experience value, in the order of emotional values and functional values, had a significant impact on positive emotion and life satisfaction of subjective well-being. Therefore, it was confirmed that the authenticity of experiential fishing villages is important as a strategy to enhance experience value and subjective well-being. Especially, considering that the majority of visitors to experiential fishing villages are family-centered (86.5%), applying marketing management strategies to develop programs that enhance existential authenticity and improve emotional values could elevate the subjective well-being of experiential visitors.