This work focuses on the problem of monitoring the coastline, which in Portugal’s case means monitoring 3007 kilometers, including 1793 maritime borders with the Atlantic Ocean to the south and west. The human burden...This work focuses on the problem of monitoring the coastline, which in Portugal’s case means monitoring 3007 kilometers, including 1793 maritime borders with the Atlantic Ocean to the south and west. The human burden on the coast becomes a problem, both because erosion makes the cliffs unstable and because pollution increases, making the fragile dune ecosystem difficult to preserve. It is becoming necessary to increase the control of access to beaches, even if it is not a popular measure for internal and external tourism. The methodology described can also be used to monitor maritime borders. The use of images acquired in the infrared range guarantees active surveillance both day and night, the main objective being to mimic the infrared cameras already installed in some critical areas along the coastline. Using a series of infrared photographs taken at low angles with a modified camera and appropriate filter, a recent deep learning algorithm with the right training can simultaneously detect and count whole people at close range and people almost completely submerged in the water, including partially visible targets, achieving a performance with F1 score of 0.945, with 97% of targets correctly identified. This implementation is possible with ordinary laptop computers and could contribute to more frequent and more extensive coverage in beach/border surveillance, using infrared cameras at regular intervals. It can be partially automated to send alerts to the authorities and/or the nearest lifeguards, thus increasing monitoring without relying on human resources.展开更多
Wireless Sensor Network (WSN) has been emerging in the last decade as a powerful tool for connecting physical and digital world. WSN has been used in many applications such habitat monitoring, building monitoring, sma...Wireless Sensor Network (WSN) has been emerging in the last decade as a powerful tool for connecting physical and digital world. WSN has been used in many applications such habitat monitoring, building monitoring, smart grid and pipeline monitoring. In addition, few researchers have been experimenting with WSN in many mission-critical applications such as military applications. This paper surveys the literature for experimenting work done in border surveillance and intrusion detection using the technology of WSN. The potential benefits of using WSN in border surveillance are huge;however, up to our knowledge very few attempts of solving many critical issues about this application could be found in the literature.展开更多
Nowadays the computer vision technique has widely found applicationsin industrial manufacturing process to improve their efficiency. However, it ishardly applied in the field of daily ceramic detection due to the foll...Nowadays the computer vision technique has widely found applicationsin industrial manufacturing process to improve their efficiency. However, it ishardly applied in the field of daily ceramic detection due to the following twokey reasons: (1) Low detection accuracy as a result of ceramic glare, and (2) Lackof efficient detection algorithms. To tackle these problems, a homomorphic filtering based anti-glare ceramic decals defect detection technique is proposed in thispaper. Considering that smooth ceramic surface usually causes glare effects andleads to low detection results, in our approach, the ceramic samples are takenin low light environment and their luminance and details restored by a homomorphic filtering based image enhancement technique. With relatively high quality preprocessed images, an effective ceramic decal defect detection algorithm isthen designed to rapidly locate those out-of-bounds defects and further estimatetheir size. The experimental results show that the proposed scheme could achieveits desired performance.展开更多
Intravascular ultrasound can provide high-resolution real-time cross-sectional images about lumen, plaque and tissue. Traditionally, the luminal border and medial-adventitial border are traced manually. This process i...Intravascular ultrasound can provide high-resolution real-time cross-sectional images about lumen, plaque and tissue. Traditionally, the luminal border and medial-adventitial border are traced manually. This process is extremely time-consuming and the subjective difference would be large. In this paper, a new automated contour detection method is introduced based on fast active contour model. Experimental results found that lumen and vessel area measurements after automated detection showed good agreement with manual tracings with high correlation coefficients (0.94 and 0.95, respectively) and small system difference (-0.32 and 0.56, respectively). So it can be a reliable and accurate diagnostic tool.展开更多
针对红外船舶目标在海上复杂海天背景下检测困难,且数据集目标大小与锚框不符造成的算法边界回归效果差、检测不准确等问题,提出了一种基于改进YOLOv5的红外船舶目标检测算法。首先针对锚框与数据集目标形状不匹配问题,通过改变K-means+...针对红外船舶目标在海上复杂海天背景下检测困难,且数据集目标大小与锚框不符造成的算法边界回归效果差、检测不准确等问题,提出了一种基于改进YOLOv5的红外船舶目标检测算法。首先针对锚框与数据集目标形状不匹配问题,通过改变K-means++聚类算法选取簇中心的评价标准,使用中位数代替平均数来决定簇中心,改进了锚框算法,使得锚框与船舶目标更加匹配,提高了算法的平均检测精度。改进后的聚类算法得到的锚框更加符合目标的分布特点。其次针对CIoU(Complete intersection over union)存在梯度爆炸、误检和漏检问题,通过改进边框回归损失函数中关于长宽比的惩罚项提出了MIoU(Multivariate intersection over union)回归损失函数,优化了算法的回归过程,提高了算法的收敛速度和检测精度,避免了相似目标的误检和漏检。改进后的回归损失函数使边框损失降低了1.5%。在红外船舶数据集上进行了消融实验和对比实验,消融实验结果表明文中改进算法的平均检测精度值相较于标准YOLOv5算法提高了1.1%,对比实验结果表明文中改进算法相较于其他改进YOLOv5算法具有更高的平均检测精度,验证了文中改进算法的优越性,提升了红外船舶目标的检测效果。展开更多
文摘This work focuses on the problem of monitoring the coastline, which in Portugal’s case means monitoring 3007 kilometers, including 1793 maritime borders with the Atlantic Ocean to the south and west. The human burden on the coast becomes a problem, both because erosion makes the cliffs unstable and because pollution increases, making the fragile dune ecosystem difficult to preserve. It is becoming necessary to increase the control of access to beaches, even if it is not a popular measure for internal and external tourism. The methodology described can also be used to monitor maritime borders. The use of images acquired in the infrared range guarantees active surveillance both day and night, the main objective being to mimic the infrared cameras already installed in some critical areas along the coastline. Using a series of infrared photographs taken at low angles with a modified camera and appropriate filter, a recent deep learning algorithm with the right training can simultaneously detect and count whole people at close range and people almost completely submerged in the water, including partially visible targets, achieving a performance with F1 score of 0.945, with 97% of targets correctly identified. This implementation is possible with ordinary laptop computers and could contribute to more frequent and more extensive coverage in beach/border surveillance, using infrared cameras at regular intervals. It can be partially automated to send alerts to the authorities and/or the nearest lifeguards, thus increasing monitoring without relying on human resources.
文摘Wireless Sensor Network (WSN) has been emerging in the last decade as a powerful tool for connecting physical and digital world. WSN has been used in many applications such habitat monitoring, building monitoring, smart grid and pipeline monitoring. In addition, few researchers have been experimenting with WSN in many mission-critical applications such as military applications. This paper surveys the literature for experimenting work done in border surveillance and intrusion detection using the technology of WSN. The potential benefits of using WSN in border surveillance are huge;however, up to our knowledge very few attempts of solving many critical issues about this application could be found in the literature.
基金supported by the Science and Technology Projects,Quzhou City,China(2019K12,X.Chen,www.qz.gov.cn)National Natural Science Foundation of China(61762054 and 62062044,X.Chen)。
文摘Nowadays the computer vision technique has widely found applicationsin industrial manufacturing process to improve their efficiency. However, it ishardly applied in the field of daily ceramic detection due to the following twokey reasons: (1) Low detection accuracy as a result of ceramic glare, and (2) Lackof efficient detection algorithms. To tackle these problems, a homomorphic filtering based anti-glare ceramic decals defect detection technique is proposed in thispaper. Considering that smooth ceramic surface usually causes glare effects andleads to low detection results, in our approach, the ceramic samples are takenin low light environment and their luminance and details restored by a homomorphic filtering based image enhancement technique. With relatively high quality preprocessed images, an effective ceramic decal defect detection algorithm isthen designed to rapidly locate those out-of-bounds defects and further estimatetheir size. The experimental results show that the proposed scheme could achieveits desired performance.
文摘Intravascular ultrasound can provide high-resolution real-time cross-sectional images about lumen, plaque and tissue. Traditionally, the luminal border and medial-adventitial border are traced manually. This process is extremely time-consuming and the subjective difference would be large. In this paper, a new automated contour detection method is introduced based on fast active contour model. Experimental results found that lumen and vessel area measurements after automated detection showed good agreement with manual tracings with high correlation coefficients (0.94 and 0.95, respectively) and small system difference (-0.32 and 0.56, respectively). So it can be a reliable and accurate diagnostic tool.
文摘针对红外船舶目标在海上复杂海天背景下检测困难,且数据集目标大小与锚框不符造成的算法边界回归效果差、检测不准确等问题,提出了一种基于改进YOLOv5的红外船舶目标检测算法。首先针对锚框与数据集目标形状不匹配问题,通过改变K-means++聚类算法选取簇中心的评价标准,使用中位数代替平均数来决定簇中心,改进了锚框算法,使得锚框与船舶目标更加匹配,提高了算法的平均检测精度。改进后的聚类算法得到的锚框更加符合目标的分布特点。其次针对CIoU(Complete intersection over union)存在梯度爆炸、误检和漏检问题,通过改进边框回归损失函数中关于长宽比的惩罚项提出了MIoU(Multivariate intersection over union)回归损失函数,优化了算法的回归过程,提高了算法的收敛速度和检测精度,避免了相似目标的误检和漏检。改进后的回归损失函数使边框损失降低了1.5%。在红外船舶数据集上进行了消融实验和对比实验,消融实验结果表明文中改进算法的平均检测精度值相较于标准YOLOv5算法提高了1.1%,对比实验结果表明文中改进算法相较于其他改进YOLOv5算法具有更高的平均检测精度,验证了文中改进算法的优越性,提升了红外船舶目标的检测效果。
