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Clinical study on improving the diagnostic accuracy of adult elbow joint cartilage injury by multisequence magnetic resonance imaging
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作者 Wei-Wei Ding Lei Ding +6 位作者 Li Li Pan Zhang Rui Gong Jian Li Meng-Ying Xu Feng Ding Bing Chen 《World Journal of Clinical Cases》 SCIE 2024年第25期5673-5680,共8页
BACKGROUND Due to frequent and high-risk sports activities,the elbow joint is susceptible to injury,especially to cartilage tissue,which can cause pain,limited movement and even loss of joint function.AIM To evaluate ... BACKGROUND Due to frequent and high-risk sports activities,the elbow joint is susceptible to injury,especially to cartilage tissue,which can cause pain,limited movement and even loss of joint function.AIM To evaluate magnetic resonance imaging(MRI)multisequence imaging for improving the diagnostic accuracy of adult elbow cartilage injury.METHODS A total of 60 patients diagnosed with elbow cartilage injury in our hospital from January 2020 to December 2021 were enrolled in this retrospective study.We analyzed the accuracy of conventional MRI sequences(T1-weighted imaging,T2-weighted imaging,proton density weighted imaging,and T2 star weighted image)and Three-Dimensional Coronary Imaging by Spiral Scanning(3D-CISS)in the diagnosis of elbow cartilage injury.Arthroscopy was used as the gold standard to evaluate the diagnostic effect of single and combination sequences in different injury degrees and the consistency with arthroscopy.RESULTS The diagnostic accuracy of 3D-CISS sequence was 89.34%±4.98%,the sensitivity was 90%,and the specificity was 88.33%,which showed the best performance among all sequences(P<0.05).The combined application of the whole sequence had the highest accuracy in all sequence combinations,the accuracy of mild injury was 91.30%,the accuracy of moderate injury was 96.15%,and the accuracy of severe injury was 93.33%(P<0.05).Compared with arthroscopy,the combination of all MRI sequences had the highest consistency of 91.67%,and the kappa value reached 0.890(P<0.001).CONCLUSION Combination of 3D-CISS and each sequence had significant advantages in improving MRI diagnostic accuracy of elbow cartilage injuries in adults.Multisequence MRI is recommended to ensure the best diagnosis and treatment. 展开更多
关键词 MRI multisequence imaging Cartilage injury of elbow joint Accuracy of diagnosis ARTHROSCOPY 3D-CISS
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Analysis of The Value of Multi-Slice Spiral CT and Magnetic Resonance Imaging in The Diagnosis of Carpal Joint Injury
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作者 Rongfeng An Juntao Lu +1 位作者 Jingzhong Liu Fang Yan 《Journal of Clinical and Nursing Research》 2024年第5期145-149,共5页
Objective:To analyze the value of multi-slice spiral computed tomography(CT)and magnetic resonance imaging(MRI)in the diagnosis of carpal joint injury.Methods:A total of 130 patients with suspected wrist injuries admi... Objective:To analyze the value of multi-slice spiral computed tomography(CT)and magnetic resonance imaging(MRI)in the diagnosis of carpal joint injury.Methods:A total of 130 patients with suspected wrist injuries admitted to the Department of Orthopedics of our hospital from January 2023 to January 2024 were selected and randomly divided into a single group(n=65)and a joint group(n=65).The single group was diagnosed using multi-slice spiral CT,and the joint group was diagnosed using multi-slice spiral CT and magnetic resonance imaging,with pathological diagnosis as the gold standard.The diagnostic results of both groups were compared to the gold standard,and the diagnostic energy efficiency of both groups was compared.Results:The diagnostic results of the single group compared with the gold standard were significant(P<0.05).The diagnostic results of the joint group compared with the gold standard were not significant(P>0.05).The sensitivity and accuracy of diagnosis in the joint group were significantly higher than that in the single group(P<0.05).The specificity of diagnosis in the joint group was higher as compared to that in the single group(P>0.05).Conclusion:The combination of multi-slice spiral CT and MRI was highly accurate in diagnosing wrist injuries,and the misdiagnosis rate and leakage rate were relatively low.Hence,this diagnostic program is recommended to be popularized. 展开更多
关键词 Multi-slice CT Magnetic resonance imaging Carpal joint injury joint diagnosis
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Imaging of the temporomandibular joint: An update 被引量:7
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作者 Asim K Bag Santhosh Gaddikeri +4 位作者 Aparna Singhal Simms Hardin Benson D Tran Josue A Medina Joel K Curé 《World Journal of Radiology》 CAS 2014年第8期567-582,共16页
Imaging of the temporomandibular joint(TMJ) is continuously evolving with advancement of imaging technologies. Many different imaging modalities are currently used to evaluate the TMJ. Magnetic resonance imaging is co... Imaging of the temporomandibular joint(TMJ) is continuously evolving with advancement of imaging technologies. Many different imaging modalities are currently used to evaluate the TMJ. Magnetic resonance imaging is commonly used for evaluation of the TMJ due to its superior contrast resolution and its ability to acquire dynamic imaging for demonstration of the functionality of the joint. Computed tomography and ultrasound imaging have specific indication in imaging of the TMJ. This article focuses on state of the art imaging of the temporomandibular joint. Relevant normal anatomy and biomechanics of movement of the TMJ are discussed for better understanding of many TMJ pathologies. Imaging of internal derangements is discussed in detail. Different arthropathies and commontumors are also discussed in this article. 展开更多
关键词 TEMPOROMANDIBULAR joint Magnetic resonance imaging imaging COMPUTED tomography ANATOMY PATHOLOGIES
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Measurement of micro weld joint position based on magneto-optical imaging
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作者 高向东 陈子琴 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期517-523,共7页
In a laser butt joint welding process, it is required that the laser beam focus should be controlled to follow the weld joint path accurately. Small focus wandering off the weld joint may result in insufficient penetr... In a laser butt joint welding process, it is required that the laser beam focus should be controlled to follow the weld joint path accurately. Small focus wandering off the weld joint may result in insufficient penetration or unacceptable welds.Recognition of joint position offset, which describes the deviation between the laser beam focus and the weld joint, is important for adjusting the laser beam focus and obtaining high quality welds. A new method based on the magneto-optical(MO) imaging is applied to measure the micro weld joint whose gap is less than 0.2 mm. The weldments are excited by an external magnetic field, and an MO sensor based on principle of Faraday magneto effect is used to capture the weld joint images. A sequence of MO images which are tested under different magnetic field intensities and different weld joint widths are acquired. By analyzing the MO image characteristics and extracting the weld joint features, the influence of magnetic field intensity and weld joint width on the MO images and detection of weld joint position is observed and summarized. 展开更多
关键词 micro weld joint magneto-optical imaging laser welding
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Linear inversion-imaging method based on joint primary refl ected waves and surface-related multiples
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作者 Ouyang Min Sheng Shen +1 位作者 Liu Shou-Wei Feng Bo 《Applied Geophysics》 SCIE CSCD 2022年第3期366-377,471,共13页
In marine seismic exploration,especially in deep-water and hard ocean-bottom cases,free-surface multiples are strongly developed.Compared with primary waves,the wider illumination aperture of the multiples is benefici... In marine seismic exploration,especially in deep-water and hard ocean-bottom cases,free-surface multiples are strongly developed.Compared with primary waves,the wider illumination aperture of the multiples is beneficial for high-resolution seismic imaging.In this study,by introducing a new compound source composed of primaries and free-surface multiples and by ignoring internal multiples,we derive a new linearized forward problem(free-surface-multiple prediction model)under a weak-scattering assumption(i.e.,first-order Born approximation).On the basis of the new linearized problem,we propose a joint inversion-imaging method by simultaneously using the primaries and free-surface multiples under the general framework of least square inversion.To eliminate the crosstalk artifacts introduced by the cross-correlation of multiples with different orders,we prove that the crosstalk artifacts can be gradually eliminated during the inversion if a proper step length is selected.Synthetic-andfield-data tests demonstrate the effectiveness of the proposed method. 展开更多
关键词 Free-surface multiple joint linearized imaging crosstalk artifact iterative convergence
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Microwave-induced thermoacoustic imaging of joints
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作者 Zi-Hui Chi Shuang Du +3 位作者 Yang Wang Lin Huang Dan Wu Hua-Bei Jiang 《Journal of Electronic Science and Technology》 EI CAS CSCD 2023年第2期1-13,共13页
Due to the complexity of joint structures and the diversity of disorders in the joints,the diagnosis of joint diseases is challenging.Current clinical diagnostic techniques for evaluating joint diseases,such as arthri... Due to the complexity of joint structures and the diversity of disorders in the joints,the diagnosis of joint diseases is challenging.Current clinical diagnostic techniques for evaluating joint diseases,such as arthritis,have strengths and weaknesses.New imaging techniques need to be developed for the diagnosis or auxiliary diagnosis of arthritis.As an emerging nonintrusive low-cost imaging method,microwave-induced thermoacoustic imaging(TAI)can present tissue morphology while providing the tissue microwave energy absorption density distribution related to dielectric properties.TAI is currently in development to potentially visualize joint anatomic structures and to detect arthritis.Here,we offer a mini review to summarize the status of research on TAI of joints and present an outlook to the future development of TAI in the detection of joint diseases. 展开更多
关键词 Arthritis detection joint structures Thermoacoustic imaging(TAI)
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Diagnostic use of superb microvascular imaging in evaluating septic arthritis of the manubriosternal joint:A case report
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作者 Goda Seskute Dominyka Kausaite +2 位作者 Ana Chalkovskaja Egle Bulotaite Irena Butrimiene 《World Journal of Clinical Cases》 SCIE 2023年第18期4397-4405,共9页
BACKGROUND Septic arthritis of the manubriosternal joint is a diagnostic challenge due to its rarity and anatomical characteristic.Conventional ultrasound,plain radiographs,and computed tomography are not able to conf... BACKGROUND Septic arthritis of the manubriosternal joint is a diagnostic challenge due to its rarity and anatomical characteristic.Conventional ultrasound,plain radiographs,and computed tomography are not able to confirm or even suspect arthritis early.Superb microvascular imaging is a new advanced Doppler technique in evaluating low-flow microvascular patterns.The higher sensitivity for increased perisynovial vascularity helps to suspect septic arthritis and forms a methodical approach to using magnetic resonance imaging(MRI).CASE SUMMARY A 34-year-old immunocompetent woman presented with a fever and a dull ache in the chest radiating to the right arm.Traumatic injury and the most common respiratory and cardiac disorders were ruled out.Blood cultures came back positive for Staphylococcus aureus,and sepsis was confirmed.A small lump was noted on the chest during the first week of hospitalization.Superb microvascular imaging was performed and septic arthritis of the manubriosternal joint was detected.MRI confirmed the diagnosis and showed septic arthritis of the manubriosternal joint with several localized abscesses behind the sternum.The patient was treated for three weeks with intravenous antibiotics and the outcome was favorable:Inflammatory markers became normal,and the lump disappeared.Three months later,the patient was examined for a new episode of mild pain in the sternum and was diagnosed with persistent perichondritis by ultrasound in comparison with MRI.CONCLUSION Superb microvascular imaging is a useful tool for the early diagnosis of septic arthritis of the manubriosternal joint and following-up. 展开更多
关键词 Power Doppler Superb microvascular imaging ULTRASOUND Septic arthritis Manubriosternal joint Case report
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Low complexity joint source-channel decoding for transmission of wavelet compressed images
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作者 殷玮玮 梅中辉 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期148-152,共5页
To utilize residual redundancy to reduce the error induced by fading channels and decrease the complexity of the field model to describe the probability structure for residual redundancy, a simplified statistical mode... To utilize residual redundancy to reduce the error induced by fading channels and decrease the complexity of the field model to describe the probability structure for residual redundancy, a simplified statistical model for residual redundancy and a low complexity joint source-channel decoding(JSCD) algorithm are proposed. The complicated residual redundancy in wavelet compressed images is decomposed into several independent 1-D probability check equations composed of Markov chains and it is regarded as a natural channel code with a structure similar to the low density parity check (LDPC) code. A parallel sum-product (SP) and iterative JSCD algorithm is proposed. Simulation results show that the proposed JSCD algorithm can make full use of residual redundancy in different directions to correct errors and improve the peak signal noise ratio (PSNR) of the reconstructed image and reduce the complexity and delay of JSCD. The performance of JSCD is more robust than the traditional separated encoding system with arithmetic coding in the same data rate. 展开更多
关键词 joint source-channel decoding sum-product algorithm generalized distribution law wavelet compressed image
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Magnetic resonance imaging in glenohumeral instability 被引量:7
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作者 Manisha Jana Shivanand Gamanagatti 《World Journal of Radiology》 CAS 2011年第9期224-232,共9页
The glenohumeral joint is the most commonly dislocated joint of the body and anterior instability is the most common type of shoulder instability.Magnetic resonance (MR) imaging,and more recently,MR arthrography,have ... The glenohumeral joint is the most commonly dislocated joint of the body and anterior instability is the most common type of shoulder instability.Magnetic resonance (MR) imaging,and more recently,MR arthrography,have become the essential investigation modalities of glenohumeral instability,especially for pre-procedure evaluation before arthroscopic surgery.Injuries associated with glenohumeral instability are variable,and can involve the bones,the labor-ligamentous components,or the rotator cuff.Anterior instability is associated with injuries of the anterior labrum and the anterior band of the inferior glenohumeral ligament,in the form of Bankart lesion and its variants;whereas posterior instability is associated with reverse Bankart and reverse Hill-Sachs lesion.Multidirectional instability often has no labral pathology on imaging but shows specific osseous changes such as increased chondrolabral retroversion.This article reviews the relevant anatomy in brief,the MR imaging technique and the arthrographic technique,and describes the MR findings in each type of instability as well as common imaging pitfalls. 展开更多
关键词 SHOULDER joint INSTABILITY MAGNETIC RESONANCE imaging MAGNETIC RESONANCE arthrogram
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Determination of geological strength index of jointed rock mass based on image processing 被引量:8
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作者 Kunui Hong Eunchol Han Kwangsong Kang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第4期702-708,共7页
The geological strength index(GSI) system,widely used for the design and practice of mining process,is a unique rock mass classification system related to the rock mass strength and deformation parameters based on the... The geological strength index(GSI) system,widely used for the design and practice of mining process,is a unique rock mass classification system related to the rock mass strength and deformation parameters based on the generalized Hoek-Brown and Mohr-Coulomb failure criteria.The GSI can be estimated using standard chart and field observations of rock mass blockiness and discontinuity surface conditions.The GSI value gives a numerical representation of the overall geotechnical quality of the rock mass.In this study,we propose a method to determine the GSI quantitatively using photographic images of in situ jointed rock mass with image processing technology,fractal theory and artificial neural network(ANN).We employ the GSI system to characterize the jointed rock mass around the working in a coal mine.The relative error between the proposed value and the given value in the GSI chart is less than 3.6%. 展开更多
关键词 jointed rock mass Geological strength index(GSI) image processing Fractal dimension Artificial neural network(ANN)
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Clinical applications of advanced magnetic resonance imaging techniques for arthritis evaluation 被引量:3
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作者 Teodoro Martín Noguerol Antonio Luna +1 位作者 Marta Gómez Cabrera Alexie D Riofrio 《World Journal of Orthopedics》 2017年第9期660-673,共14页
Magnetic resonance imaging(MRI) has allowed a comprehensive evaluation of articular disease, increasing the detection of early cartilage involvement, bone erosions, and edema in soft tissue and bone marrow compared to... Magnetic resonance imaging(MRI) has allowed a comprehensive evaluation of articular disease, increasing the detection of early cartilage involvement, bone erosions, and edema in soft tissue and bone marrow compared to other imaging techniques. In the era of functional imaging, new advanced MRI sequences are being successfully applied for articular evaluation in cases of inflammatory, infectious, and degenerative arthropathies. Diffusion weighted imaging, new fat suppression techniques such as DIXON, dynamic contrast enhanced-MRI, and specific T2 mapping cartilage sequences allow a better understanding of the physiopathological processes that underlie these different arthropathies. They provide valuable quantitative information that aids in their differentiation and can be used as potential biomarkers of articular disease course and treatment response. 展开更多
关键词 Magnetic resonance imaging joint Diffusion weighted imaging Dynamic contrast enhanced MUSCULOSKELETAL system CARTILAGE DIXON ARTHRITIS
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Digital image processing-based automatic detection algorithm of cross joint trace and its application in mining roadway excavation practice 被引量:2
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作者 Yuxin Yuan Nong Zhang +3 位作者 Changliang Han Sen Yang Zhengzheng Xie Jin Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第6期1219-1231,共13页
This paper proposes a digital image processing-based detection algorithm for cross joint traces of coal roadway heading face.Initially,the acquired images were preprocessed,i.e.,adaptive correction was conducted for n... This paper proposes a digital image processing-based detection algorithm for cross joint traces of coal roadway heading face.Initially,the acquired images were preprocessed,i.e.,adaptive correction was conducted for non-uniform illumination images based on the 2D gamma function.The edge detection algorithm was then applied to extract the edges of the structural plane,followed by the filtration of the non-structural plane noises.Moreover,the Hough transform algorithm was applied to extract the linear edges;finally,the edges were locally connected in accordance with the angle and distance criteria.The experimental results show that this algorithm can be used to reduce the noise caused by non-uniform illumination and avoid the mutual interference of multi-scale edges,so as to effectively extract the traces of the cross joint.Furthermore,Q-system and rock mass rating(RMR),were applied to conduct a quantitative evaluation on the stand-up time of unsupported roof in the four test images.The Q-system quality scores are 26.7,43.3,3.1,and 6.7,and the RMR quality scores are 56.84,58.73,48.42,and 51.42,respectively.The stand-up time of unsupported roofs with a span of 4.6 m are 30,36,7.7 and 14 d,respectively. 展开更多
关键词 Coal roadway Cross joint image detection Stand-up time evaluation
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Magnetic resonance imaging-based interpretation of degenerative changes in the lower lumbar segments and therapeutic consequences 被引量:4
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作者 Adel Maataoui Thomas J Vogl M Fawad Khan 《World Journal of Radiology》 CAS 2015年第8期194-197,共4页
Intervertebral disc degeneration and facet joint osteoarthritis of the lumbar spine are, among others, wellknown as a cause of low back and lower extremity pain. Together with their secondary disorders they set a big ... Intervertebral disc degeneration and facet joint osteoarthritis of the lumbar spine are, among others, wellknown as a cause of low back and lower extremity pain. Together with their secondary disorders they set a big burden on health care systems and economics worldwide. Despite modern imaging modalities, such as magnetic resonance imaging, for a large proportion of patients with low back pain(LBP) it remains difficult to provide a specific diagnosis. The fact that nearly all the lumbar structures are possible sources of LBP, may serve as a possible explanation. Furthermore, our clinical experience confirms, that imaging alone is not a sufficient approach explaining LBP. Here, the Oswestry Disability Index, as the most commonly used measure to quantify disability for LBP, may serve as an easy-toapply questionnaire to evaluate the patient's ability to cope with everyday life. For therapeutic purposes, among the different options, the lumbar facet joint intraarticular injection of corticosteroids in combination with an anaesthetic solution is one of the most frequently performed interventional procedures. Although widely used the clinical benefit of intra-articular steroid injections remains controversial. Therefore, prior to therapy, standardized diagnostic algorithms for an accurate assessment, classification and correlation of degenerative changes of the lumbar spine are needed. 展开更多
关键词 Low back pain SPINE Intervertebral disc disease Facet joint osteoarthritis Magnetic resonance imaging Oswestry Disability Index
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Near-field 3D imaging approach combining MJSR and FGG-NUFFT 被引量:3
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作者 WANG Shuzhen FANG Yang +2 位作者 ZHANG Jin’gang LUO Mingshi LI Qing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1096-1109,共14页
A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of t... A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of the compressed sensing(CS)theory and the matched filtering(MF)technique.The approach has the advantages of high precision and high efficiency:multichannel joint sparse constraint is adopted to improve the problem that the images recovered by the single channel imaging algorithms do not necessarily share the same positions of the scattering centers;the CS dictionary is constructed by combining MF and FGG-NUFFT,so as to improve the imaging efficiency and memory requirement.Firstly,a near-field 3 D imaging model of joint sparse recovery is constructed by combining the MF-based imaging method.Secondly,FGG-NUFFT and reverse FGG-NUFFT are used to replace the interpolation and Fourier transform in MF-based imaging methods,and a sensing matrix with high precision and high efficiency is constructed according to the traditional imaging process.Thirdly,a fast imaging recovery is performed by using the improved separable surrogate functionals(SSF)optimization algorithm,only with matrix and vector multiplication.Finally,a 3 D imagery of the near-field target is obtained by using both the horizontal and the pitching interferometric phase information.This paper contains two imaging models,the only difference is the sub-aperture method used in inverse synthetic aperture radar(ISAR)imaging.Compared to traditional CS-based imaging methods,the proposed method includes both forward transform and inverse transform in each iteration,which improves the quality of reconstruction.The experimental results show that,the proposed method improves the imaging accuracy by about O(10),accelerates the imaging speed by five times and reduces the memory usage by about O(10~2). 展开更多
关键词 interference imaging joint sparse recovery compressed sensing(CS) matching filtering(MF) fast Gaussian gridding nonuniform fast Fourier transform(NUFFT) near-field 3D imaging
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Impact of Conjugated Shear Joint of“X”Type on Macroscopic Karstification on the Basis of the Analysis of Google Earth Images 被引量:1
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作者 YANG Ruidong SHENG Xueyong +1 位作者 WEI Xiao WEN Xuefeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期520-530,共11页
As viewed from space remote-sensing images (e.g. Google Earth images) of South Guizhou and North Guangxi, the authors found that macroscopic karst landscape on the Earth's surface is strongly controlled by the Conj... As viewed from space remote-sensing images (e.g. Google Earth images) of South Guizhou and North Guangxi, the authors found that macroscopic karst landscape on the Earth's surface is strongly controlled by the Conjugated shear joint of "X" type. Joints of this kind constitute a huge infiltration network and act as channel-ways for the permeation of meteoric waters from the surface, thus, leading to the dissolution of carbonate rocks nearby. As a result, the karst landscape is formed, which is dominated by linear karst valleys. An "X" karst valley network structure appears in the area where horizontal strata are distributed, and a feather-like network structure appears in the area where vertical strata are distributed, respectively. When the water permeates downwards to the underground-water level, it will flow horizontally along the strike of "X" joints toward the local base level of erosion to form an "X" network system of underground conduits in the area where horizontal strata are distributed, but it is relatively complex, because of the joining of other joints. This is the first time we have made use of Google Earth images to study the karst environment. Therefore, it has been successful in research on the Earth's geomorphology, which could only rely on aerial photos and satellite photos in the past. Google Earth images provide low-cost and applicable imaging materials for the study of Earth's geomorphology and karst rocky desertification and its control. 展开更多
关键词 KARSTIFICATION Google Earth image conjugated shear joint of"X" type
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NEW SAR IMAGE INTERPRETATION METHOD OF AIRCRAFT BASED ON JOINT TIME-FREQUENCY ANALYSIS 被引量:1
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作者 Zhu Jiwei Qiu Xiaolan Lei Bin 《Journal of Electronics(China)》 2014年第4期325-333,共9页
With the continuous improvement of Synthetic Aperture Radar(SAR) resolution, interpreting the small targets like aircraft in SAR images becomes possible and turn out to be a hot spot in SAR application research. Howev... With the continuous improvement of Synthetic Aperture Radar(SAR) resolution, interpreting the small targets like aircraft in SAR images becomes possible and turn out to be a hot spot in SAR application research. However, due to the complexity of SAR imaging mechanism, interpreting targets in SAR images is a tough problem. This paper presents a new aircraft interpretation method based on the joint time-frequency analysis and multi-dimensional contrasting of basic structures. Moreover, SAR data acquisition experiment is designed for interpreting the aircraft. Analyzing the experiment data with our method, the result shows that the proposed method largely makes use of the SAR data information. The reasonable results can provide some auxiliary support for the SAR images manual interpretation. 展开更多
关键词 Synthetic Aperture Radar (SAR) image interpretation joint time-frequency analysis Scattering centers Basic structureCLC number:TN957
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Monitoring of weld joint penetration by sensing double-side vision images of weld pool
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作者 娄亚军 陈善本 吴林 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期26-31,共6页
In order to emulate a skilled human operator determining weld penetration from feature sizes of weld pool,such us topside maximum width and half-length of weld pool, a CCD camera assisted with electronic shutter and c... In order to emulate a skilled human operator determining weld penetration from feature sizes of weld pool,such us topside maximum width and half-length of weld pool, a CCD camera assisted with electronic shutter and composed filter system is used to simultaneously capture topside and backside images of weld pool in the same frame. Neural networks are used to investigate the complicated relationships between the weld penedrion and different parameters, they are capabe of modeling complicated nonlinear functions. Bead-on-plate welding experiments and simulations show that a neural network model has adequate accuracy required for monitoring full penetration duringpulsed GTAW dynamic process. 展开更多
关键词 GTAW WELD joint PENETRATION WELD POOL imag NEURAL networks
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An image joint compression-encryption algorithm based on adaptive arithmetic coding
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作者 邓家先 邓海涛 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期403-408,共6页
Through a series of studies on arithmetic coding and arithmetic encryption, a novel image joint compression- encryption algorithm based on adaptive arithmetic coding is proposed. The contexts produced in the process o... Through a series of studies on arithmetic coding and arithmetic encryption, a novel image joint compression- encryption algorithm based on adaptive arithmetic coding is proposed. The contexts produced in the process of image compression are modified by keys in order to achieve image joint compression encryption. Combined with the bit-plane coding technique, the discrete wavelet transform coefficients in different resolutions can be encrypted respectively with different keys, so that the resolution selective encryption is realized to meet different application needs. Zero-tree coding is improved, and adaptive arithmetic coding is introduced. Then, the proposed joint compression-encryption algorithm is simulated. The simulation results show that as long as the parameters are selected appropriately, the compression efficiency of proposed image joint compression-encryption algorithm is basically identical to that of the original image compression algorithm, and the security of the proposed algorithm is better than the joint encryption algorithm based on interval splitting. 展开更多
关键词 image compression joint compression-encryption algorithm arithmetic encryption progressiveclassification encryption
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Association between Magnetic Resonance Imaging and the Result of Medial Branch Blocks
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作者 Stephan Klessinger Wolfgang Freund 《Pain Studies and Treatment》 2017年第1期1-10,共10页
The aim of this retrospective practice audit was to assess the correlation between painful zygapophysial joints and changes seen in magnetic resonance imaging (MRI). Patients with unilateral pain were tested with cont... The aim of this retrospective practice audit was to assess the correlation between painful zygapophysial joints and changes seen in magnetic resonance imaging (MRI). Patients with unilateral pain were tested with controlled medial branch blocks. The MRI scans of patients with a positive response were compared blinded with normal MRI scans. The dimensions of the joint were assessed and osteoarthritis was graded. Fifteen symptomatic patients and 15 asymptomatic patients were included and evaluated. Comparison of the joints showed that the maximum diameter of symptomatic joints was significantly larger, and the grading of osteoarthritis was significantly higher for symptomatic joints. No healthy patient was assigned a grade 3. Grades 2 and 3 were found significantly more often in symptomatic patients. Only one symptomatic joint was assigned grade 0. Grade 0 was found significantly more often in asympto-matic patients. The presented MRI technique has limited value as a diagnostic test for lumbar zygapophysial joint pain. It is not possible to detect a single symptomatic joint. However, the osteoarthritis grading for the lumbar zyg-apophysial joints might be helpful for finding predictors for negative response if the results of the rating are grade zero. Therefore, unnecessary medial branch blocks might be avoided. 展开更多
关键词 Zygapophysial joint FACET joint SPINE Back PAIN MEDIAL Branch Block Magnet Resonance imaging INTERVENTIONAL PAIN
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Use of Image processing software in Hip Joint surgery
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作者 Rashmi Uddanwadiker 《Advances in Bioscience and Biotechnology》 2011年第2期68-74,共7页
The scope of this project was to investigate the possibility of application of Image Processing Technique in the field of Shaft Alignment process. Misalignment of shaft using image processing software Visionbuilder wa... The scope of this project was to investigate the possibility of application of Image Processing Technique in the field of Shaft Alignment process. Misalignment of shaft using image processing software Visionbuilder was calculated. The further purpose of this project was to check whether the image processing technique can be used in bone transplant surgery. The model of the hip was used for the experimentation purpose. Image processing software Visionbuilder was used to match the profiles of the bone before implant and bone after implant. 展开更多
关键词 image Processing SHAFT ALIGNMENT HIP joint BONE TRANSPLANT
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