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Intelligent extraction of road cracks based on vehicle laser point cloud and panoramic sequence images
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作者 Ming Guo Li Zhu +4 位作者 Ming Huang Jie Ji Xian Ren Yaxuan Wei Chutian Gao 《Journal of Road Engineering》 2024年第1期69-79,共11页
In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strat... In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road cracks.This methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of images.The study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence image.The extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic image.Additionally,a threshold value is set based on the crack elevation change to extract the aligned roadway point cloud.The three-dimensional data pertaining to the cracks can be acquired.The experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road cracks.The utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road cracks.This approach exhibits superior accuracy when compared to conventional methods.Moreover,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic safety.Consequently,this technique finds extensive application in the domains of intelligent transportation and urbanization development.The technology exhibits significant promise for use in the domains of intelligent transportation and city development. 展开更多
关键词 Road crack extraction Vehicle laser point cloud panoramic sequence images Convolutional neural network
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Geographical Information Visualization on a Panoramic Sphere in an Immersive Environment
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作者 MA Ying TIAN Fenglin +3 位作者 LIU Wen TANG Moran LI Jinyu CHEN Ge 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期961-974,共14页
In this paper,we propose a novel approach to visualizing global geographical information:a panoramic sphere in an immersive environment.The whole geographical surface can be observed through the rotating of heads as t... In this paper,we propose a novel approach to visualizing global geographical information:a panoramic sphere in an immersive environment.The whole geographical surface can be observed through the rotating of heads as the viewpoint of the panoramic sphere is inside the sphere.We compared three approaches to visualizing the earth for rendering the geographical information in a virtual reality environment.On the tasks of terrestrial and marine geographical information,we compare the visualization effects on a)a globe,b)a flat map and c)a panoramic sphere.Terrestrial geographical information tasks include the area comparison and direction determination.Marine geographical information tasks contain the visualization of sea surface temperature and sea surface currents.For terrestrial geographical information tasks,the experimental results show that the panoramic sphere outperforms the globe and the flat map,with a higher average accuracy and a shorter time.On marine geographical information task,the panoramic sphere visualization is also superior to the flat map and the globe in an immersive environment for the sea surface temperature data and the sea surface current fields.In all three visualization experiments,the panoramic sphere is most preferred by the participants,particularly for global,transcontinental and transoceanic needs. 展开更多
关键词 the panoramic sphere immersive environment virtual reality oceanographic information visualization
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Transfer learning-based super-resolution in panoramic models for predicting mandibular third molar extraction difficulty: a multi-center study
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作者 Wen Li Yang Li +4 位作者 Xiao-Ling Liu Xiang-Long Zheng Shi-Yu Gao Hui-Min Huangfu Li-Song Lin 《Medical Data Mining》 2023年第4期1-7,共7页
Background:This study aims to predict the extraction difficulty of mandibular third molars based on panoramic images using transfer learning while employing super-resolution(SR)technology to enhance the feasibility an... Background:This study aims to predict the extraction difficulty of mandibular third molars based on panoramic images using transfer learning while employing super-resolution(SR)technology to enhance the feasibility and validity of the prediction.Methods:We reviewed a total of 608 preoperative mandibular third molar panoramic radiographs from two medical facilities:the First Affiliated Hospital of Zhengzhou University(n=509;456 in the training set and 53 in the test set)and the Henan Provincial Dental Hospital(n=99 in the validation set).We conducted a deep-transfer learning network on high-resolution(HR)panoramic radiographs to improve the longitudinal resolution of the images and obtained the SR images.Subsequently,we constructed models named Model-HR and Model-SR using high-dimensional quantitative features extracted through the Least Absolute Shrinkage and Selection Operator method.The models’performances were evaluated using the receiver operating characteristic curve(ROC).To assess the reliability of the model,we compared the results from the test set with those of three dentists.Results:Model-SR outperformed Model-HR(area under the curve(AUC):0.779,sensitivity:85.5%,specificity:60.9%,and accuracy:79.8%vs.AUC:0.753,sensitivity:73.7%,specificity:73.9%,and accuracy:73.7%)in predicting the difficulty of extracting mandibular third molars.Both Model-HR(AUC=0.821,95%CI 0.687–0.956)and Model-SR(AUC=0.963,95%CI 0.921–0.999)demonstrated superior performance compared to expert dentists(highest AUC=0.799,95%CI 0.671–0.927).Conclusions:Model-SR yielded superior predictive performance in determining the difficulty of extracting mandibular third molars when compared with Model-HR and expert dentists’visual assessments. 展开更多
关键词 SUPER-RESOLUTION transfer-learning mandibular third molar extraction difficulty panoramic radiographs
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Bionic Mosaic Method of Panoramic Image Based on Compound Eye of Fly 被引量:8
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作者 Haipeng Chen Xuanjing Shen +1 位作者 Xiaofei Li Yushan Jin 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第4期440-448,共9页
To satisfy the requirements of real-time and high quality mosaics, a bionic compound eye visual system was designed by simulating the visual mechanism of a fly compound eye. Several CCD cameras were used in this syste... To satisfy the requirements of real-time and high quality mosaics, a bionic compound eye visual system was designed by simulating the visual mechanism of a fly compound eye. Several CCD cameras were used in this system to imitate the small eyes of a compound eye. Based on the optical analysis of this system, a direct panoramic image mosaic algorithm was proposed. Several sub-images were collected by the bionic compound eye visual system, and then the system obtained the overlapping proportions of these sub-images and cut the overlap sections of the neighboring images. Thus, a panoramic image with a large field of view was directly mosaicked, which expanded the field and guaranteed the high resolution. The experimental results show that the time consumed by the direct mosaic algorithm is only 2.2% of that by the traditional image mosaic algorithm while guaranteeing mosaic quality. Furthermore, the proposed method effectively solved the problem of misalignment of the mosaic image and eliminated mosaic cracks as a result of the illumination factor and other factors. This method has better real-time properties compared to other methods. 展开更多
关键词 bionic compound eye panoramic image image mosaic direct mosaic algorithm
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Research and Implementation of Algorithm for Image Enhancement and Unwrapped Distortion Correction for SLVF Panoramic Night Vision Image 被引量:3
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作者 张振海 李科杰 +1 位作者 高峻峣 段星光 《Journal of Beijing Institute of Technology》 EI CAS 2008年第4期423-428,共6页
Abstract: Based on digital signal processor(DSP) and field programmable gate array(FPGA) techniques, the architecture of super large view field(SLVF) panoramic night vision image processing hardware platform wa... Abstract: Based on digital signal processor(DSP) and field programmable gate array(FPGA) techniques, the architecture of super large view field(SLVF) panoramic night vision image processing hardware platform was established. The panoramic unwrapping and correcting algorithm, up to a full 360°, based on coordinate rotation digital computer (CORDIC) and night vision image enhancement algorithm, based on histogram equalization theory and edge detection theory, was presented in this paper, with the purpose of processing night vision dynamic panoramic annular image. The annular image can be unwrapped and corrected to conventional rectangular panorama by the panoramic image processing algorithm, which uses the pipelined CORDIC configuration to realize a trigonometric function generator with high speed and high precision. Histogram equalization algorithm can perfectly enhance the contrast of the night vision image. Edge detection algorithm can be propitious to find and detect small dim dynamic targets in night vision circumstances. After abundant experiment, the al- gorithm for panoramic image processing and night vision image enhancement is successfully implemented in FPGA and DSP. The panoramic night vision image system is a compact device, with no external rotating parts. And the system can reliably and dynamically detect 360* SLVF panoramic night vision image. 展开更多
关键词 panoramic annular image CORDIC image enhancement unwrapped algorithm FPGA and DSP
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Panoramic Imaging System Inspired by Insect Compound Eyes 被引量:1
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作者 邢强 王浩 戴振东 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第3期287-292,共6页
Inspired by the unique structure of insect compound eyes,a multi-channel image acquisition system is designed to photograph a cylindrical panorama of its surroundings with one shot. The hardware structure consists of ... Inspired by the unique structure of insect compound eyes,a multi-channel image acquisition system is designed to photograph a cylindrical panorama of its surroundings with one shot. The hardware structure consists of an embedded ARM system and one array of 16 micro-image sensors. The system achieves the synchronization of captured photos in 10 ms,as well as 10 f /s video capture. The software architecture includes the TCP /IP protocol,video capture procedures in"Poll/Read"or"video streaming"modes,thread pool monitoring in multi-threading mutex,synchronization control with the"event""mutex signal"and"critical region"functions,and a synthetic image algorithm characterized by its portability,modularity,and remote transmission. The panoramic imaging system is expected to be a vision sensor for mobile robotics. 展开更多
关键词 multi-channel image acquisition cylindrical panoramic image MULTI-THREAD embedded ARM
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Research on DSO vision positioning technology based on binocular stereo panoramic vision system 被引量:1
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作者 Xiao-dong Guo Zhou-bo Wang +4 位作者 Wei Zhu Guang He Hong-bin Deng Cai-xia Lv Zhen-hai Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第4期593-603,共11页
In the visual positioning of Unmanned Ground Vehicle(UGV),the visual odometer based on direct sparse method(DSO) has the advantages of small amount of calculation,high real-time performance and high robustness,so it i... In the visual positioning of Unmanned Ground Vehicle(UGV),the visual odometer based on direct sparse method(DSO) has the advantages of small amount of calculation,high real-time performance and high robustness,so it is more widely used than the visual odometer based on feature point method.Ordinary vision sensors have a narrower viewing angle than panoramic vision sensors,and there are fewer road signs in a single frame of image,resulting in poor road sign tracking and positioning capabilities,and severely restricting the development of visual odometry.Based on these considerations,this paper proposes a binocular stereo panoramic vision positioning algorithm based on extended DSO,which can solve these problems well.The experimental results show that the binocular stereo panoramic vision positioning algorithm based on the extended DSO can directly obtain the panoramic depth image around the UGV,which greatly improves the accuracy and robustness of the visual positioning compared with other ordinary visual odometers.It will have widely application prospects in the UGV field in the future. 展开更多
关键词 panoramic vision DSO Visual positioning
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A race to uncover a panoramic view of primary liver cancer 被引量:1
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作者 Ruidong Xue Jing Li +3 位作者 Fan Bai Xinwei Wang Junfang Ji Yinying Lu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2017年第4期335-340,共6页
Introduction Primary liver cancer,the second most common cause of cancer related death worldwide1,presents ethnic,etiological,sex,and geographical diversity2(Figure 1A).At the histological level,liver cancer includes ... Introduction Primary liver cancer,the second most common cause of cancer related death worldwide1,presents ethnic,etiological,sex,and geographical diversity2(Figure 1A).At the histological level,liver cancer includes two major types:hepatocellular carcinoma(HCC,about 80%)and cholangiocarcinoma(CCA,about 15%).Many etiological factors contribute to HCC development,such as hepatitis 展开更多
关键词 HCC A race to uncover a panoramic view of primary liver cancer CCA
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Overall Bi-directional Panoramic Exploration of the Solar System 被引量:1
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作者 WU Zhimin ZHAO Jincai 《Aerospace China》 2019年第2期46-52,共7页
An overall bi-directional panoramic solar system exploration activity,not just looking at the solar system at a macro level and helping to build a simulation model for the solar system,but the probe will also be able ... An overall bi-directional panoramic solar system exploration activity,not just looking at the solar system at a macro level and helping to build a simulation model for the solar system,but the probe will also be able to explore the Milky Way and the vast universe from a much wider perspective.By observing the characteristics of the solar system,solar wind,ionization envelope and other parameters from a bi-directional panorama on both sides of the solar ecliptic plane,it will assist the scientific community and human kind to understand the solar system in a more extensive,deeper and systematic way than before.The exploration can be done in two steps.The first step is to launch a solar polar probe.Secondly to launch a bi-directional probe orbiting the galaxy in sync with the sun. 展开更多
关键词 overall bi-directional panoramic EXPLORATION SOLAR SYSTEM
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A 360-Degree Panoramic Image Inpainting Network Using a Cube Map
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作者 Seo Woo Han Doug Young Suh 《Computers, Materials & Continua》 SCIE EI 2021年第1期213-228,共16页
Inpainting has been continuously studied in the field of computer vision.As artificial intelligence technology developed,deep learning technology was introduced in inpainting research,helping to improve performance.Cu... Inpainting has been continuously studied in the field of computer vision.As artificial intelligence technology developed,deep learning technology was introduced in inpainting research,helping to improve performance.Currently,the input target of an inpainting algorithm using deep learning has been studied from a single image to a video.However,deep learning-based inpainting technology for panoramic images has not been actively studied.We propose a 360-degree panoramic image inpainting method using generative adversarial networks(GANs).The proposed network inputs a 360-degree equirectangular format panoramic image converts it into a cube map format,which has relatively little distortion and uses it as a training network.Since the cube map format is used,the correlation of the six sides of the cube map should be considered.Therefore,all faces of the cube map are used as input for the whole discriminative network,and each face of the cube map is used as input for the slice discriminative network to determine the authenticity of the generated image.The proposed network performed qualitatively better than existing single-image inpainting algorithms and baseline algorithms. 展开更多
关键词 panoramic image image inpainting cube map generative adversarial networks
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Electronic stabilization of catadioptric panoramic image
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作者 马子领 王建中 《Journal of Beijing Institute of Technology》 EI CAS 2011年第2期238-243,共6页
An effective algorithm of electronic image stabilization (EIS) of catadioptric panoramic imaging system for track robots is presented. The key techniques of this algorithm are as follows:① A model of electronic im... An effective algorithm of electronic image stabilization (EIS) of catadioptric panoramic imaging system for track robots is presented. The key techniques of this algorithm are as follows:① A model of electronic image stabilization is built by analyzing the imaging theory and the principle of EIS, and the image shift function of unwrapped panoramic image is deduced;② The relationship equation between motion estimation parameters of annular panoramic image and motion estimation parameters of unwrapped panoramic image is developed according to the constrained aspect ratio of real objects, motion parameters of annular panoramic image are firstly estimated, and then motion parameters among the image shift function are carried out according to the relationship equation;③ An excessive stabilization threshold is presented to prevent the phenomena of excessive stabilization, and the Kalman filtering is adopted to smooth the image sequences. Numerical experimental results show that this algorithm can effectively smooth out the unwanted motion and follow the intentional camera movement under certain resolutions. 展开更多
关键词 catadioptric panoramic imaging electronic image stabilization Kalman filtering
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Rapid digitalization and panoramic evaluation of weld X-ray film
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作者 闫志鸿 宋永伦 +1 位作者 王彬 李元香 《China Welding》 EI CAS 2011年第1期49-53,共5页
The computer evaluation of weld X-ray film is an attractive technique for weld seam NDT ( nondestructive testing). To achieve this target, digitalization of film is the first step and automatic defect identification... The computer evaluation of weld X-ray film is an attractive technique for weld seam NDT ( nondestructive testing). To achieve this target, digitalization of film is the first step and automatic defect identification is another key technique. In this paper, a weld X-ray film digitalizing system has been established with linear array CCD and highlight LED light source. Its space resolution can reach 0. 04 mm/pixel and scanning speed can reach 100 mm/s for an industrial film. The transfer function curves of the system have been measured and the results indicate that its image gray resolution can reach 88 G/D at 4. 5D, and its dynamic range can be wider than 2. OD. In order to facilitate the evaluation of large welded structure, a panoramic evaluation algorithm is developed also. The algorithm includes image matching, image fusion and panoramic evaluation of the long linked film image. 展开更多
关键词 weld X-ray film rapid digitalization image processing panoramic evaluation
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Evaluation of Positive Predictive Value for Digital Panoramic Radiography in Comparison to Ultrasound in the Diagnosis of Calcified Carotid Atheroma
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作者 Fatemeh Ezoddini-Ardakani Maryam Mirzaei +2 位作者 Saman Nayer Sajad Besharati Malihe Moeini 《Health》 2014年第15期1933-1940,共8页
Aim: Detection of calcified carotid atheroma (CCA) has an important role in reducing the incidence of Cerebro Vascular Accident (CVA). The aim of this study was to evaluate efficacy of panoramic digital radiography in... Aim: Detection of calcified carotid atheroma (CCA) has an important role in reducing the incidence of Cerebro Vascular Accident (CVA). The aim of this study was to evaluate efficacy of panoramic digital radiography in detecting atherosclerosis. Methods: It is descriptive-analytical diagnostic study. The people (22 to 62 years old) were referred to a radiology clinic to perform panoramic radiography for diagnosis of CCA. Individuals who were suspected were introduced to the radiology department of dental school to undergo ultrasound evaluation to CCA. For the 41 patients (55 sides), ultrasound was performed. For data analysis, the Chi-square and Fisher's exact test were used. Results: The prevalence of CCA was 2.43%. The PPV of digital panoramic was 45.5%. There was no significant relationship between age (P = 0.14) and sex (P = 0.539) and PPV of digital panoramic. The PPV of digital panoramic was significantly associated with hypertension (P = 0.032). Conclusion: It seems that panoramic can be used to screen patients with a history of hypertension for atherosclerosis. 展开更多
关键词 RADIOGRAPHY panoramic DIGITAL Ultrasonography Atherosclerosis
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Investigation of coronoid process hyperplasia using Levandoski analysis on panoramic radiographs
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作者 Sule Erdem Suheda Erdem 《World Journal of Radiology》 2022年第5期107-113,共7页
BACKGROUND The diagnosis of coronoid process hyperplasia(CPH)is usually based on symptoms and radiological imaging.Because of its similar symptoms,it can be confused with temporomandibular joint diseases.Therefore,an ... BACKGROUND The diagnosis of coronoid process hyperplasia(CPH)is usually based on symptoms and radiological imaging.Because of its similar symptoms,it can be confused with temporomandibular joint diseases.Therefore,an objective and reproducible way of diagnosis should be determined.AIM To investigate CPH using Levandoski analysis on panoramic radiographs to determine its prevalence.METHODS A total of 300 panoramic radiograph images(600 coronoid processes)were examined.Having measured the Condyle-Gonion(Cd-Go)and Coronoid-Gonion(Cor-Go)distances,the Cor-Go:Cd-Go ratio was calculated for the left and right sides of each image.RESULTS There was a statistically significant difference in Cd-Go and Cor-Go distances between male and female participants(P<0.001).There was no statistically significant relationship between Cor-Go:Cd-Go ratios and gender(P>0.05).CONCLUSION Cd-Go and Cor-Go distances were statistically significantly increased in males on both the left and right sides.The ratio of Cor-Go:Cd-Go was preserved in both genders.The prevalence of CPH was found to be 0.3%. 展开更多
关键词 Coronoid process HYPERPLASIA PREVALENCE Levandoski analysis panoramic radiograph
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Association of type 2 diabetes mellitus with the reduction of mandibular residual ridge among edentulous patients using panoramic radiographs
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作者 Osama Al-Jabrah 《Open Journal of Stomatology》 2011年第3期61-68,共8页
Objective: To evaluate the association between type 2 diabetes mellitus and the reduction of mandibular residual ridge in completely edentulous patients wearing complete dentures and to investigate the ef-fect of gend... Objective: To evaluate the association between type 2 diabetes mellitus and the reduction of mandibular residual ridge in completely edentulous patients wearing complete dentures and to investigate the ef-fect of gender, age and years of edentulousness / den-ture wearing on ridge resorption on both groups. Methods: Seventy-two (36 men and 36 women) with a mean age 63.5 years (range of 52 to 73 years) com-pletely edentulous denture-wearing patients were included in this study. Of these, there were 40 patients with type 2 diabetes mellitus and 32 control subjects participated in the study. Resorption in the mandibular residual ridges was assessed by using the mental foramen and the inferior border of the mandible, as they appear in panoramic radiographs, as reference points using Wical and Swoope Analysis method. Measurements were performed using “Dijite” Digital Caliper. The amount of mandibular ridge resorption was calculated and correlated with type 2 diabetes mellitus and the results were compared with control group. Differences in gender, age and years of edentulousness were investigated. Statistical analysis was performed using SPSS (V11.0). A 2-sample t-test was used to evaluate the differences in mean values of mandibular ridge resorption between diabetics and controls. Level of significance was set at 0.05. Results: The mean mandibular residual ridge resorption of all participants is 8.0 mm (26.9%), diabetic group significantly (P < 0.01) had two times more resorption compared with control group (35.8% versus 18.0%). Females recorded greater amount of resorption in diabetics 49.7% versus 21.8% (P < 0.001) and in controls 22.3% versus 13.7%, (P < 0.05) compared to males, respectively. There were no differences in both groups regarding the age of subjects and the length of time they have been edentulous and years of denture wearing. The amount of mandibular residual ridge resorption was directly related to the number of years of edentulousness. Conclusion: Completely edentulous, denture-wearing diabetics, women in particular, are at more risk to have ridge resorption than “nondiabetic” subjects. Reduced mandibular height is directly related to years of edentulousness and denture wear-ing with greater amount of resorption among diabet-ics. 展开更多
关键词 Type 2 Diabetes Mellitus Residual Ridge RESORPTION MANDIBLE Mental Foramen EDENTULOUS Complete DENTURE panoramic Radiology
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Rheumatoid Arthritis of the Temporomandibular Joint;Comparison of Digital Panoramic Radiographs Taken Using the Joint Limitation Program [JLA View] and CT Scans
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作者 Antigone Delantoni 《Open Journal of Rheumatology and Autoimmune Diseases》 2012年第3期59-63,共5页
Objective: The aim of this study was to evaluate the efficacy of digital panoramic radiographs using the JLA view pro-gram in cases of rheumatoid arthritis and compare them to CT scans of the patients. Methods: 40 pat... Objective: The aim of this study was to evaluate the efficacy of digital panoramic radiographs using the JLA view pro-gram in cases of rheumatoid arthritis and compare them to CT scans of the patients. Methods: 40 patients with known condition of RA and clinical symptoms in the TMJ were selected for the study. Radiological evaluation included a panoramic radiograph of the TMJs that was taken and a computer tomography of the joints. In the panoramic radio-graphs taken, isolation of the TMJs was done using the JLA view program, while in the CT scans of the patients, all scans were taken with closed mouth, with a distance of 0.5 mm per slice. The parameters examined were: 1) Bony changes of the condyle;2) The position of the condyle in the mandibular fossa;3) The joint space;4) Bony changes of mandibular fossa. Results: There were no statistically significant differences found between the two observers or be-tween the two joints of the same patient [right and left] on the panoramic radiographs. For the case of CT scans there were significant differences between the joint space of right and left joints, while in the ANOVA performed differences were found for the evaluation of the bony changes of the condyle. Conclusion: There were no significant differences between the two radiographic methods selected and therefore when a proper simple radiograph is taken and well evalu-ated, the conclusions drawn from it are well based and there is no need for further 展开更多
关键词 RHEUMATOID ARTHRITIS Imaging TEMPOROMANDIBULAR Joint panoramic RADIOGRAPHY
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Analysis of Bone Quality on Panoramic Radiograph in Osteoporosis Research by Fractal Dimension
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作者 Angela Jordão Camargo Arthur Rodriguez Gonzalez Côrtes +3 位作者 Eduardo Massaharu Aoki Marina Gazzano Baladi Emiko Saito Arita Plauto Christopher Aranha Watanabe 《Applied Mathematics》 2016年第4期375-386,共12页
Objective: To Assess the correlation between different quality analysis parameters of trabecular pattern in digital panoramic radiographies and relations with forearm bone mass density (BMD) performed by DXA. Methods:... Objective: To Assess the correlation between different quality analysis parameters of trabecular pattern in digital panoramic radiographies and relations with forearm bone mass density (BMD) performed by DXA. Methods: The study was developed using panoramic and peripheral bone densitometry dual energy X-ray absorptiometry (DXA) of 68 patients, 9 males and 59 females (19 - 73 years old). In the panoramic radiographs, evaluation of the trabecular bone morphology through assessment of fractal dimension (FD), connectivity (C) and total number of “bright” pixels (ET) was performed. In DXA, the exam determines the bone mineral density of the forearm to identify who has a high risk of osteoporosis. Statistics analyzed the relationship of these exams and the contribution of dental radiographs in detecting patients at risk for osteoporosis. Results: The average age of subjects was 43.85. In the analysis of trabecular pattern, a significant correlation between the FD, ET and C factors in level of 5% (Pearson correlation test) was found. Correlation tests showed no significant correlation between DF and BMD. Conclusions: The analysis showed correlations with each other, detecting alterations in the trabecular pattern. It cannot be related to BMD with FD but should be taken into account that examining the bone or trabecular alveolar process, when, for example, diagnostic analysis of pre-implant bone quality, is required. 展开更多
关键词 Fractals panoramic Radiography OSTEOPOROSIS MANDIBLE DXA Scan
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Relevance and Compliance of Requests for Dental Panoramic Radiography Examination at Yaounde (Cameroon)
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作者 Armel Philippe Awana Ambroise Merci Seme Engoumou +2 位作者 Mballa Amougou Jean Goni Ismaila Odile Fernande Zeh 《Advances in Molecular Imaging》 2020年第4期31-37,共7页
<strong>Background:</strong> Research studies made in Cameroon on compliance and relevance in the various areas of imaging, show the failure to comply with administrative and clinical criteria. These resea... <strong>Background:</strong> Research studies made in Cameroon on compliance and relevance in the various areas of imaging, show the failure to comply with administrative and clinical criteria. These research studies led to recommendations meant for result amelioration. However, the orthopantomogram (OPT) field remains less studied in that regard in Cameroon. <strong>Aim:</strong> Evaluate the relevance and compliance of examination requests for panoramic dental radiography. <strong>Setting and Design:</strong> It is a descriptive cross-sectional study with a consecutive sample of dental panoramic requests identified during the study period in 4 radiology centres of Yaoundé. <strong>Material and Methods:</strong> Variables studied here were the validity criteria of imaging examination. <strong>Request:</strong> Five of which are of administrative order (date of the request, requesting department, patient’s identity, patient’s age, applicant’s identity) and three of clinical order (anatomic region, reason for the examination and the purpose of the examination). <strong>Statistical Analysis:</strong> Chi-squared test was used with confidence interval of 95%. <strong>Results:</strong> Patient’s identity (name) was the criteria carrying the highest information (98.9%), followed by the name of the applicant physician (91.6%). Out of 179 requests analysed, 8.6% had complete information. 46.4% of requests had no indications. Dental surgeon was the top prescriber with a total of 112 (62.6%). <strong>Conclusion:</strong> The quality of dental panoramic requests was not optimal in Yaounde, with lack of precision mostly noted at the level of clinical criteria. 展开更多
关键词 COMPLIANCE RELEVANCE REQUEST panoramic Dental Orthopantomogram
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Perceptual quality assessment of panoramic stitched contents for immersive applications:a prospective survey
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作者 Hayat ULLAH Sitara AFZAL Imran Ullah KHAN 《Virtual Reality & Intelligent Hardware》 2022年第3期223-246,共24页
The recent advancements in the field of Virtual Reality(VR)and Augmented Reality(AR)have a substantial impact on modern day technology by digitizing each and everything related to human life and open the doors to the ... The recent advancements in the field of Virtual Reality(VR)and Augmented Reality(AR)have a substantial impact on modern day technology by digitizing each and everything related to human life and open the doors to the next generation Software Technology(Soft Tech).VR and AR technology provide astonishing immersive contents with the help of high quality stitched panoramic contents and 360°imagery that widely used in the education,gaming,entertainment,and production sector.The immersive quality of VR and AR contents are greatly dependent on the perceptual quality of panoramic or 360°images,in fact a minor visual distortion can significantly degrade the overall quality.Thus,to ensure the quality of constructed panoramic contents for VR and AR applications,numerous Stitched Image Quality Assessment(SIQA)methods have been proposed to assess the quality of panoramic contents before using in VR and AR.In this survey,we provide a detailed overview of the SIQA literature and exclusively focus on objective SIQA methods presented till date.For better understanding,the objective SIQA methods are classified into two classes namely Full-Reference SIQA and No-Reference SIQA approaches.Each class is further categorized into traditional and deep learning-based methods and examined their performance for SIQA task.Further,we shortlist the publicly available benchmark SIQA datasets and evaluation metrices used for quality assessment of panoramic contents.In last,we highlight the current challenges in this area based on the existing SIQA methods and suggest future research directions that need to be target for further improvement in SIQA domain. 展开更多
关键词 Virtual reality Augmented reality panoramic image Immersive contents Stitched image quality assessment Deep learning Convolutional neural networks
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Extra-Oral Digital Panoramic Radiographic Interpretation and Clinical Findings of Stage IV Periodontitis among Some Samples Concerning Saudi/Non-Saudi Nationality
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作者 Mohammed M. A. Abdulla Al-Abdaly Amer Hassan Alasmari +5 位作者 Saeed J. Alqahtani Ahmed Abdulrahman Alzahrani Jawaher Moshabab A. Al Ahmari Ghadeer Mohammed Mohammed Al-Abdaly Ibrahim Hassan Ibrahim Alqaysi Mohammed Dhafer Mohammed Al-Shamrani 《Open Journal of Stomatology》 2022年第2期42-61,共20页
Background: There are associations between the severity of periodontal diseases and some predisposing factors, such as age, race, and income rate. Therefore, the present study was designed to evaluate the extra-oral d... Background: There are associations between the severity of periodontal diseases and some predisposing factors, such as age, race, and income rate. Therefore, the present study was designed to evaluate the extra-oral digital panoramic radiographic interpretation and clinical findings of stage IV periodontitis among some samples concerning Saudi/non-Saudi nationality. Material and Methods: The study comprised a random sample of 298 residents in Saudi Arabia referred to the internship program clinics at the College of Dentistry, King Khalid University. They were according to the age of participants as follows: youth (15 - 24 years), adults (25 - 64 years), and seniors (65 years and over) within two groups according to nationality (Saudi and non-Saudi). Clinical periodontal examination and radiographic extra oral digital panoramic radiographs were done, and then the periodontal parameters, the percentage of bone loss, and the pattern of bone loss were recorded. The data was collected, and the statistical analysis was performed with ANOVA test, Tukey’s test, Chi-square test, and T-test and considered a P-value at (p Results: The samples included 62 (20%) youth participants with mean of age (21.806 ± 3.390), 182 (57%) adults’ participants with mean age (42.802 ± 9.094), and 54 (23%) seniors participants with a mean age (69.074 ± 6.810). There were highly statistically significant differences in the comparison between the participants’ ages (P 0.05). Conclusion: At the end of this study, we concluded that there are alterations in clinical and radiographic and clinical findings of stage IV periodontitis with the alteration of participants’ ages and nationality. 展开更多
关键词 Extra-Oral Digital panoramic Radiographs NATIONALITY Stage IV Periodontitis
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