In order to solve the problem caused by variation illumination in human face recognition,we bring forward a face recognition algorithm based on the improved multi-sample. In this algorithm,the face image is processed ...In order to solve the problem caused by variation illumination in human face recognition,we bring forward a face recognition algorithm based on the improved multi-sample. In this algorithm,the face image is processed with Retinex theory,meanwhile,the Gabor filter is adopted to perform the feature extraction. The experimental results show that the application of Retinex theory improves the recognition accuracy,and makes the algorithm more robust to the variation illumination. The Gabor filter is more effective and accurate for extracting more useable facial local features. It is proved that the proposed algorithm has good recognition accuracy and it is stable under variation illumination.展开更多
Target detection in low light background is one of the main tasks of night patrol robots for airport terminal.However,if some algorithms can run on a robot platform with limited computing resources,it is difficult for...Target detection in low light background is one of the main tasks of night patrol robots for airport terminal.However,if some algorithms can run on a robot platform with limited computing resources,it is difficult for these algorithms to ensure the detection accuracy of human body in the airport terminal. A novel thermal infrared salient human detection model combined with thermal features called TFSHD is proposed. The TFSHD model is still based on U-Net,but the decoder module structure and model lightweight have been redesigned. In order to improve the detection accuracy of the algorithm in complex scenes,a fusion module composed of thermal branch and saliency branch is added to the decoder of the TFSHD model. Furthermore,a predictive loss function that is more sensitive to high temperature regions of the image is designed. Additionally,for the sake of reducing the computing resource requirements of the algorithm,a model lightweight scheme that includes simplifying the encoder network structure and controlling the number of decoder channels is adopted. The experimental results on four data sets show that the proposed method can not only ensure high detection accuracy and robustness of the algorithm,but also meet the needs of real-time detection of patrol robots with detection speed above 40 f/s.展开更多
Objective To investigate the incidence, imaging and clinical characteristics in elderly patients with coronary artery ectasia （CAE）. Methods A retrospective analysis was conducted on patients with CAE who underwent ...Objective To investigate the incidence, imaging and clinical characteristics in elderly patients with coronary artery ectasia （CAE）. Methods A retrospective analysis was conducted on patients with CAE who underwent coronary angiography between January 2006 and December 2012. According to age, the enrolled patients were divided into two groups （elderly group, age≥ 65 years; non-elderly group, age 〈 65 years）. The clinical feature, imaging characteristics and the 5-year survival rate of the two groups were compared.Results The preva-lence of CAE in elderly patients was 0.33%. Patients in elderly group were found to have significantly higher proportion of female （30.1%vs. 10.1%,P〈 0.001）, three-vessel disease （60.5%vs. 45.2%,P = 0.003） and localized ectasia （55.0%vs. 40.2%,P = 0.003）. In addition, body mass index （20.90 ± 2.71 kg/m2vs. 22.31 ± 2.98 kg/m2,P 〈 0.001） and percentage of current smokers （45.0%vs. 64.6%,P 〈 0.001） were significantly lower in elderly group. Cumulative survival curves demonstrated reduced 5-year cumulative survival at the follow-up in the elderly group compared with the non-elderly group （88.0%vs. 96.0%,P = 0.002）. But the 5-year event free survival rate failed to show a significant difference between the two groups （31.0%vs. 35.0%,P= 0.311）.ConclusionThe prevalence of CAE in elderly patients was 0.33%, which was about 1/3 of the entire numbers of CAE patients. There were significant differences between the elderly and the non-elderly patients with CAE in terms of coronary artery disease risk factors and coronary artery ectatic characteristics. CAE might be asso-ciated with increased mortality risk in the elderly.展开更多
In this paper, evacuation experiments are carried out to study pedestrian movement behaviors in building bottleneck. An image processing method based on mean-shift algorithm is used to extract pedestrian movement traj...In this paper, evacuation experiments are carried out to study pedestrian movement behaviors in building bottleneck. An image processing method based on mean-shift algorithm is used to extract pedestrian movement trajectory. Based on the extracted trajectory, we analyze the microscopic movement characteristics of pedestrians such as lane formation, change of velocity and distance between two sequential pedestrians. A pedestrian lane is a group of pedestrians moving in a column. The lane formation is verified by the pedestrian trajectory and distribution of pedestrian’s lateral positions (x direction in the paper): lane number changes from one to two, three or even more with the increasing bottleneck width when pedestrians pass through the bottleneck. By analyzing the pedestrian movement behaviors in the same pedestrian lane, we find three typical movement modes in the bottleneck: time-lag acceleration, synchronous acceleration, and avoiding deceleration. Through analyzing the time intervals when successive pedestrians pass through the bottleneck, we find that most pedestrians adjust their velocities according to the distance to the forward pedestrians. Results also indicate that due to different cultures, pedestrians flux in China and Germany may have some differences besides their similarities.展开更多
Computer-aided diagnosis(CAD) systems have been proposed to assist radiologists in making diagnostic decisions by providing helpful information. As one of the most important sequences in prostate magnetic resonance im...Computer-aided diagnosis(CAD) systems have been proposed to assist radiologists in making diagnostic decisions by providing helpful information. As one of the most important sequences in prostate magnetic resonance imaging(MRI), image features from T2-weighted images(T2WI) were extracted and evaluated for the diagnostic performances by using CAD. We extracted 12 quantitative image features from prostate T2-weighted MR images. The importance of each feature in cancer identification was compared in the peripheral zone(PZ) and central gland(CG), respectively. The performance of the computer-aided diagnosis system supported by an artificial neural network was tested. With computer-aided analysis of T2-weighted images, many characteristic features with different diagnostic capabilities can be extracted. We discovered most of the features(10/12) had significant difference(P<0.01) between PCa and non-PCa in the PZ, while only five features(sum average, minimum value, standard deviation, 10 th percentile, and entropy) had significant difference in CG. CAD prediction by features from T2 w images can reach high accuracy and specificity while maintaining acceptable sensitivity. The outcome is convictive and helpful in medical diagnosis.展开更多
Images with human faces comprise an essential part in the imaging realm. Occlusion or damage in facial portions will bring a remarkable discomfort and information loss. We propose an algorithm that can repair occluded...Images with human faces comprise an essential part in the imaging realm. Occlusion or damage in facial portions will bring a remarkable discomfort and information loss. We propose an algorithm that can repair occluded or damaged facial images automatically, named ‘facial image inpainting＇. Inpainting is a set of image processing methods to recover missing image portions. We extend the image inpainting methods by introducing facial domain knowledge. With the support of a face database, our approach propagates structural information, i.e., feature points and edge maps, from similar faces to the missing facial regions. Using the interred structural information as guidance, an exemplar-based image inpainting algorithm is employed to copy patches in the same face from the source portion to the missing portion. This newly proposed concept of facial image inpainting outperforms the traditional inpainting methods by propagating the facial shapes from a face database, and avoids the problem of variations in imaging conditions from different images by inferring colors and textures from the same face image. Our system produces seamless faces that are hardly seen drawbacks.展开更多
基金Sponsored by the Science and Technology Research Projects in Office of Education in Heilongjiang Province(Grant No. 11531034)the Natural Science Fund in Heilongjiang Province(Grant No. F2007-13)the Heilongjiang Postdoctoral Science Foundation (Grant No. LBH-Z06054)
文摘In order to solve the problem caused by variation illumination in human face recognition,we bring forward a face recognition algorithm based on the improved multi-sample. In this algorithm,the face image is processed with Retinex theory,meanwhile,the Gabor filter is adopted to perform the feature extraction. The experimental results show that the application of Retinex theory improves the recognition accuracy,and makes the algorithm more robust to the variation illumination. The Gabor filter is more effective and accurate for extracting more useable facial local features. It is proved that the proposed algorithm has good recognition accuracy and it is stable under variation illumination.
基金supported in part by the National Key Research and Development Program of China(No. 2018YFC0309104)the Construction System Science and Technology Project of Jiangsu Province (No.2021JH03)。
文摘Target detection in low light background is one of the main tasks of night patrol robots for airport terminal.However,if some algorithms can run on a robot platform with limited computing resources,it is difficult for these algorithms to ensure the detection accuracy of human body in the airport terminal. A novel thermal infrared salient human detection model combined with thermal features called TFSHD is proposed. The TFSHD model is still based on U-Net,but the decoder module structure and model lightweight have been redesigned. In order to improve the detection accuracy of the algorithm in complex scenes,a fusion module composed of thermal branch and saliency branch is added to the decoder of the TFSHD model. Furthermore,a predictive loss function that is more sensitive to high temperature regions of the image is designed. Additionally,for the sake of reducing the computing resource requirements of the algorithm,a model lightweight scheme that includes simplifying the encoder network structure and controlling the number of decoder channels is adopted. The experimental results on four data sets show that the proposed method can not only ensure high detection accuracy and robustness of the algorithm,but also meet the needs of real-time detection of patrol robots with detection speed above 40 f/s.
基金This article is partly supported by National Natural Sci-entific Foundation，Specialized Re-search Fund for the Doctoral Program of Higher Education of China，Fund of Capital Special Founda-tion of Clinical Application Research，Capital Health Development Fund，Bei-jing Natural Science Foundation （7131014） awarded to Dr. Jian-Jun Li
文摘Objective To investigate the incidence, imaging and clinical characteristics in elderly patients with coronary artery ectasia （CAE）. Methods A retrospective analysis was conducted on patients with CAE who underwent coronary angiography between January 2006 and December 2012. According to age, the enrolled patients were divided into two groups （elderly group, age≥ 65 years; non-elderly group, age 〈 65 years）. The clinical feature, imaging characteristics and the 5-year survival rate of the two groups were compared.Results The preva-lence of CAE in elderly patients was 0.33%. Patients in elderly group were found to have significantly higher proportion of female （30.1%vs. 10.1%,P〈 0.001）, three-vessel disease （60.5%vs. 45.2%,P = 0.003） and localized ectasia （55.0%vs. 40.2%,P = 0.003）. In addition, body mass index （20.90 ± 2.71 kg/m2vs. 22.31 ± 2.98 kg/m2,P 〈 0.001） and percentage of current smokers （45.0%vs. 64.6%,P 〈 0.001） were significantly lower in elderly group. Cumulative survival curves demonstrated reduced 5-year cumulative survival at the follow-up in the elderly group compared with the non-elderly group （88.0%vs. 96.0%,P = 0.002）. But the 5-year event free survival rate failed to show a significant difference between the two groups （31.0%vs. 35.0%,P= 0.311）.ConclusionThe prevalence of CAE in elderly patients was 0.33%, which was about 1/3 of the entire numbers of CAE patients. There were significant differences between the elderly and the non-elderly patients with CAE in terms of coronary artery disease risk factors and coronary artery ectatic characteristics. CAE might be asso-ciated with increased mortality risk in the elderly.
基金supported by the National Natural Science Foundation of China (Grant No. 91024025)the NCET Project (Grant No. 08-0518)
文摘In this paper, evacuation experiments are carried out to study pedestrian movement behaviors in building bottleneck. An image processing method based on mean-shift algorithm is used to extract pedestrian movement trajectory. Based on the extracted trajectory, we analyze the microscopic movement characteristics of pedestrians such as lane formation, change of velocity and distance between two sequential pedestrians. A pedestrian lane is a group of pedestrians moving in a column. The lane formation is verified by the pedestrian trajectory and distribution of pedestrian’s lateral positions (x direction in the paper): lane number changes from one to two, three or even more with the increasing bottleneck width when pedestrians pass through the bottleneck. By analyzing the pedestrian movement behaviors in the same pedestrian lane, we find three typical movement modes in the bottleneck: time-lag acceleration, synchronous acceleration, and avoiding deceleration. Through analyzing the time intervals when successive pedestrians pass through the bottleneck, we find that most pedestrians adjust their velocities according to the distance to the forward pedestrians. Results also indicate that due to different cultures, pedestrians flux in China and Germany may have some differences besides their similarities.
文摘Computer-aided diagnosis(CAD) systems have been proposed to assist radiologists in making diagnostic decisions by providing helpful information. As one of the most important sequences in prostate magnetic resonance imaging(MRI), image features from T2-weighted images(T2WI) were extracted and evaluated for the diagnostic performances by using CAD. We extracted 12 quantitative image features from prostate T2-weighted MR images. The importance of each feature in cancer identification was compared in the peripheral zone(PZ) and central gland(CG), respectively. The performance of the computer-aided diagnosis system supported by an artificial neural network was tested. With computer-aided analysis of T2-weighted images, many characteristic features with different diagnostic capabilities can be extracted. We discovered most of the features(10/12) had significant difference(P<0.01) between PCa and non-PCa in the PZ, while only five features(sum average, minimum value, standard deviation, 10 th percentile, and entropy) had significant difference in CG. CAD prediction by features from T2 w images can reach high accuracy and specificity while maintaining acceptable sensitivity. The outcome is convictive and helpful in medical diagnosis.
基金supported by the National Natural Science Foundation of China (No. 60525108)the National Key Technology R & D Program of China (No. 2006BAH11B03-4)
文摘Images with human faces comprise an essential part in the imaging realm. Occlusion or damage in facial portions will bring a remarkable discomfort and information loss. We propose an algorithm that can repair occluded or damaged facial images automatically, named ‘facial image inpainting＇. Inpainting is a set of image processing methods to recover missing image portions. We extend the image inpainting methods by introducing facial domain knowledge. With the support of a face database, our approach propagates structural information, i.e., feature points and edge maps, from similar faces to the missing facial regions. Using the interred structural information as guidance, an exemplar-based image inpainting algorithm is employed to copy patches in the same face from the source portion to the missing portion. This newly proposed concept of facial image inpainting outperforms the traditional inpainting methods by propagating the facial shapes from a face database, and avoids the problem of variations in imaging conditions from different images by inferring colors and textures from the same face image. Our system produces seamless faces that are hardly seen drawbacks.
