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Optimum Profiles of Endwall Contouring for Enhanced Net Heat Flux Reduction and Aerodynamic Performance 被引量:1
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作者 Arjun K S Tide P S Biju N 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期80-92,共13页
Successfully utilized non-axisymmetric endwalls to enhance turbine efficiencies(aerodynamic and turbine inlet temperatures)by controlling the characteristics of the secondary flow in a blade passage.This is accomplish... Successfully utilized non-axisymmetric endwalls to enhance turbine efficiencies(aerodynamic and turbine inlet temperatures)by controlling the characteristics of the secondary flow in a blade passage.This is accomplished by steady-state numerical hydrodynamics and deep knowledge of the field of flow.Because of the interaction between mainstream and purge flow contributing supplementary losses in the stage,non-axisymmetric endwalls are highly susceptible to the inception of purge flow exit compared to the flat and any advantage rapidly vanishes.The conclusions reveal that the supreme endwall pattern could yield a lowering of the gross pressure loss at the design stage and is related to the size of the top-loss location being productively lowered.This has led to diminished global thermal exchange lowered in the passage of the vane alone.The reverse flow adjacent to the suction side corner of the endwall is migrated farther from the vane surface,as the deviated pressure spread on the endwall accelerates the flow and progresses the reverse flow core still downstream.The depleted association between the tornado-like vortex and the corner vortex adjacent to the suction side corner of the endwall is the dominant mechanism of control in the contoured end wall.In this publication,we show that the non-axisymmetric endwall contouring by selective numerical shape change method at most prominent locations is advantageous in lowering the thermal load in turbines to augment the net heat flux reduction as well as the aerodynamic performance using multi-objective optimization. 展开更多
关键词 endwall contouring turbine VANE heat transfer phantom cooling coolant injection net heat flux reduction aerodynamic performance
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Analysis of GC×GC fingerprints from medicinal materials using a novel contour detection algorithm:A case of Curcuma wenyujin
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作者 Xinyue Yang Yingyu Sima +2 位作者 Xuhuai Luo Yaping Li Min He 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期542-551,共10页
This study introduces an innovative contour detection algorithm,PeakCET,designed for rapid and efficient analysis of natural product image fingerprints using comprehensive two-dimensional gas chromatogram(GC×GC).... This study introduces an innovative contour detection algorithm,PeakCET,designed for rapid and efficient analysis of natural product image fingerprints using comprehensive two-dimensional gas chromatogram(GC×GC).This method innovatively combines contour edge tracking with affinity propagation(AP)clustering for peak detection in GC×GC fingerprints,the first in this field.Contour edge tracking signif-icantly reduces false positives caused by“burr”signals,while AP clustering enhances detection accuracy in the face of false negatives.The efficacy of this approach is demonstrated using three medicinal products derived from Curcuma wenyujin.PeakCET not only performs contour detection but also employs inter-group peak matching and peak-volume percentage calculations to assess the compositional similarities and differences among various samples.Furthermore,this algorithm compares the GC×GC fingerprints of Radix/Rhizoma Curcumae Wenyujin with those of products from different botanical origins.The findings reveal that genetic and geographical factors influence the accumulation of secondary metabolites in various plant tissues.Each sample exhibits unique characteristic components alongside common ones,and vari-ations in content may influence their therapeutic effectiveness.This research establishes a foundational data-set for the quality assessment of Curcuma products and paves the way for the application of computer vision techniques in two-dimensional(2D)fingerprint analysis of GC×GC data. 展开更多
关键词 GC×GC Image fingerprints contour detection Clustering of mass spectra Curcuma products
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Contour Farming Suitability of the Black Soil Region in Northeast China and Its Spatial Characteristics
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作者 LI Yong ZHENG Shufeng +4 位作者 LIU Huanjun LUO Chong MENG Linghua WANG Yue WANG Liping 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1119-1133,共15页
Contour farming technology plays a key role in reducing soil erosion,enhancing water use efficiency,and fostering sustain-able agricultural development,Despite being a straightforward yet efficacious farming technique... Contour farming technology plays a key role in reducing soil erosion,enhancing water use efficiency,and fostering sustain-able agricultural development,Despite being a straightforward yet efficacious farming technique,it has not seen widespread implement-ation in China.Considering the deteriorating quality of arable lands in the Black Soil Region of Northeast China(BSR-NEC),it is ne-cessary to investigate spatial patterns and identify suitable areas for contour farming in this region.To achieve this objective,spatial autocorrelation and grouping analysis methods were employed to classify the land into four categories of suitability for contour farming:highly suitable,moderately suitable,generally suitable,and unsuitable.The results reveal that:1)the contour farming suitable area in BSR-NEC covers 89861.32 km^(2),accounting for 21.59%of arable land as of 2020.Heilongjiang Province owns the largest suitable area of 32853.68 km^(2),and Inner Mongolia has the highest proportion of 28.89%.2)In terms of the spatial distribution,regions with higher suitability for contour farming are concentrated in the Da Hinggan Mountains region,particularly Nenjiang City(Heilongjiang Province),which has the highest area of 2593.07 km^(2).Areas with a high proportion of suitable arable lands for contour farming are mainly found in the Da Hinggan Mountains and Changbai Mountains regions,with Ergun City(Inner Mongolia)having the highest pro-portion at 47.2%.Regions with higher suitability and proportion are concentrated in the Da Hinggan Mountains region,primarily cover-ing the Inner Mongolia and Heilongjiang.3)Regarding spatial clustering,both the area and proportion of suitable contour farming areas exhibit noticeable clustering effects,though not entirely consistent.4)Group analysis results designate 148 counties in BSR-NEC as highly suitable areas,predominantly located in the Changbai Mountains region,Liaodong Peninsula,Hulun Buir Plateau,and the north and south regions of the Da Hinggan Mountains.The zoning of suitable areas for contour farming in BSR-NEC informs the strategic de-velopment of policies and measures,allowing for the implementation of targeted policies in distinct areas suitable for contour farming.This provides a valuable reference for promoting contour farming technology more effectively and efficiently.re effectively and effi-ciently. 展开更多
关键词 contour farming spatial heterogeneity zoning policy spatial autocorrelation Black Soil Region of Northeast China(BSR-NEC)
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Real-time instance segmentation based on contour learning
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作者 GE Rui LIU Dengfeng +2 位作者 ZHOU Haojie CHAI Zhilei WU Qin 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期328-337,共10页
Instance segmentation plays an important role in image processing.The Deep Snake algorithm based on contour iteration deforms an initial bounding box to an instance contour end-to-end,which can improve the performance... Instance segmentation plays an important role in image processing.The Deep Snake algorithm based on contour iteration deforms an initial bounding box to an instance contour end-to-end,which can improve the performance of instance segmentation,but has defects such as slow segmentation speed and sub-optimal initial contour.To solve these problems,a real-time instance segmentation algorithm based on contour learning was proposed.Firstly,ShuffleNet V2 was used as backbone network,and the receptive field of the model was expanded by using a 5×5 convolution kernel.Secondly,a lightweight up-sampling module,multi-stage aggregation(MSA),performs residual fusion of multi-layer features,which not only improves segmentation speed,but also extracts effective features more comprehensively.Thirdly,a contour initialization method for network learning was designed,and a global contour feature aggregation mechanism was used to return a coarse contour,which solves the problem of excessive error between manually initialized contour and real contour.Finally,the Snake deformation module was used to iteratively optimize the coarse contour to obtain the final instance contour.The experimental results showed that the proposed method improved the instance segmentation accuracy on semantic boundaries dataset(SBD),Cityscapes and Kins datasets,and the average precision reached 55.8 on the SBD;Compared with Deep Snake,the model parameters were reduced by 87.2%,calculation amount was reduced by 78.3%,and segmentation speed reached 39.8 frame·s−1 when instance segmentation was performed on an image with a size of 512×512 pixels on a 2080Ti GPU.The proposed method can reduce resource consumption,realize instance segmentation tasks quickly and accurately,and therefore is more suitable for embedded platforms with limited resources. 展开更多
关键词 instance segmentation ShuffleNet V2 lightweight network contour initialization
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Body Contour in the Post-Bariatric Male Patient
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作者 Erick Zúñiga-Garza Israel Salgado-Adame +3 位作者 Claudio D. Rojas-Gutiérrez Laura María Rodríguez-Barrios Guillermo Álvarez-Sánchez Eduardo Camacho-Quintero 《Modern Plastic Surgery》 2024年第2期15-22,共8页
Background: Obesity is currently considered a public health problem. Bariatric procedures have become an important part of obesity management and, consequently, the number of male patients seeking post-bariatric recon... Background: Obesity is currently considered a public health problem. Bariatric procedures have become an important part of obesity management and, consequently, the number of male patients seeking post-bariatric reconstructive procedures have increased. Therefore, the clinical approach and understanding of the body contour of this population have become more relevant. The goal of post-bariatric reconstruction is to enhance the male silhouette through removal of skin and adipose tissue excess, and abdominal rectus diastasis repair. Material and Methods: We conducted a retrospective study at the Plastic and Reconstructive Surgery Department of the National Medical Center “20 de Noviembre”. All male patients referred to our department to start a post-bariatric reconstruction protocol from January 2018 to December 2022 were included in this study. Results: In total, 15 patients who underwent corporal contouring procedures were included;median age was 49.2 years with minimum of 33 years, and a maximum of 57 years. Median Body mass index was 28.4 kg/m<sup>2</sup> with minimum of 22 kg/m<sup>2</sup> and maximum of 38 kg/m<sup>2</sup>. All patients were treated 18 months after their bariatric surgery. All patients underwent an abdominoplasty as a body contouring procedure. 4 (26.7%) patients presented complications related to the surgery. Conclusion: We described a comprehensive and systematic approach to massive weight loss for male patients, suggesting an abdominal marking based on the patient’s clinical features and the expected results avoiding feminization of the abdominal body contour. 展开更多
关键词 Massive Weight Loss Post-Bariatric MALE ABDOMINOPLASTY contourING
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Clinical Efficacy of GBR Technique Combined with Temporary Bridgework-Guided Gingival Contouring in Treating Upper Anterior Tooth Loss with Labial Bone Defects
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作者 Yu Ma Jirui Ma 《Journal of Clinical and Nursing Research》 2024年第6期171-176,共6页
Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.M... Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions. 展开更多
关键词 Upper anterior teeth loss Labial bone defects Guided bone regeneration(GBR)technique Temporary bridgework-guided gingival contouring
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Comprehensive contour prediction model of work rolls in hot wide strip mill 被引量:8
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作者 Xiaodong Wang Quan Yang Anrui He Renzhong Wang 《Journal of University of Science and Technology Beijing》 CSCD 2007年第3期240-245,共6页
The predictive calculation of comprehensive contour of work rolls in the on-line strip shape control model during hot rolling consists of two important parts of wear contour calculation and thermal contour calculation... The predictive calculation of comprehensive contour of work rolls in the on-line strip shape control model during hot rolling consists of two important parts of wear contour calculation and thermal contour calculation, which have a direct influence on the ac- curacy of shape control. A statistical wear model and a finite difference thermal contour model of work rolls were described. The comprehensive contour is the equivalence treatment of the sum of grinding, wear, and thermal contours. This comprehensive contour calculation model has been applied successfully in the real on-line strip shape control model. Its high precision has been proved through the large amounts of actual roll profile measurements and theoretical analyses. The hit rates (percent of shape index satisfying re- quirement) of crown and head flatness of the strips rolled, by using the shape control model, which includes the comprehensive contour calculation model, have about 16% and 10% increase respectively, compared to those of strips rolled by using manual operation. 展开更多
关键词 hot rolled strip strip shape control comprehensive contour wear contour thermal contour
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活动轮廓模型和Contourlet多分辨率分析分割血管内超声图像 被引量:20
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作者 张麒 汪源源 +3 位作者 王威琪 马剑英 钱菊英 葛均波 《光学精密工程》 EI CAS CSCD 北大核心 2008年第11期2303-2311,共9页
针对传统图像分割方法中初始化和鲁棒性两个问题,研究了基于活动轮廓模型和Contourlet多分辨率分析分割血管内超声斑块图像的新方法。该方法运用Contourlet变换将原图像分解为多分辨率低通分量和多分辨率带通分量方向性子带。对低通分... 针对传统图像分割方法中初始化和鲁棒性两个问题,研究了基于活动轮廓模型和Contourlet多分辨率分析分割血管内超声斑块图像的新方法。该方法运用Contourlet变换将原图像分解为多分辨率低通分量和多分辨率带通分量方向性子带。对低通分量进行模板匹配,确定血管内腔边界和中-外膜边界的初始轮廓;对带通分量方向性子带进行扩散滤波,抑制噪声的同时尽可能保留有用边缘,并结合边界矢量场使轮廓演化得到最终分割结果,从而提高了分割算法的鲁棒性。对100幅仿真图像和120幅实际图像的分割结果表明,相对于传统活动轮廓模型,该方法分割实际图像的平均距离误差提高了3.04 pixel,面积差异百分比提高了6.30%。表明该方法能自动、精确地提取血管的两条边界。 展开更多
关键词 活动轮廓模型 contourLET变换 多分辨率分析 血管内超声图像分割
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Internal residual stress measurement on linear friction welding of titanium alloy plates with contour method 被引量:11
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作者 刘川 董春林 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1387-1392,共6页
The internal residual stress within a TC 17 titanium alloy joint welded by linear friction welding (LFW) was measured by the contour method, which is a relatively new and destructive technique to obtain a full map o... The internal residual stress within a TC 17 titanium alloy joint welded by linear friction welding (LFW) was measured by the contour method, which is a relatively new and destructive technique to obtain a full map of internal residual stress. The specimen was first cut into two parts; the out-of-plane displacement contour formed by the release of the residual stress was then measured; finally, taking the measured contour of the cut plane as the boundary conditions, a linear elastic finite element analysis was carried out to calculate the corresponding distribution of residual stress normal to the cut plane. The internal stress distribution of the TC 17 titanium alloy LFWjoint was also analyzed. The results show that the tensile residual stress in the TC17 LFW weld is mainly present within a region about 12 mm from the weld centerline; the peak tensile residual stress occurs at the weld centerline and reaches 360 MPa (about one third of the yield strength of TC17 alloy); within the weld zone of the TC17 LFW weld, the through-thickness stress is not uniform, and the internal stress is larger than that near the top or bottom surface. 展开更多
关键词 residual stress linear friction welding titanium alloy contour method
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CONTOUR EXTRACTION AND FEATURE POINT DETECTION FOR 3-D FRAGMENT REASSEMBLY 被引量:3
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作者 朱延娟 周来水 王坚 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第1期23-29,共7页
An approach to contour extraction and feature point detection in the 3-D fragment reassembly is proposed. A simple and effective technique is used for building the intrinsic topology of the fragment data suitable for ... An approach to contour extraction and feature point detection in the 3-D fragment reassembly is proposed. A simple and effective technique is used for building the intrinsic topology of the fragment data suitable for contour extraction. For the scanned data in which the topology is difficult to be achieved, the corresponding solutions are given to manage this problem. A robust approach is used for the curvature and torsion calculation of the discrete contour in a 3-D space. Finally, a method is developed for detecting feature points of the fragment contour based on total curvature. Therefore, the contour description combines the simple global information with local feature points. Experiments with real contour curves extracted from 3-D fragments demonstrate that the proposed method is robust and efficient. 展开更多
关键词 fragment contour mesh topology convolution approach total curvature
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凯途(CONTOUR)在低位直肠癌双吻合器技术中的应用 被引量:8
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作者 白文启 梁小波 +1 位作者 张鑫 王立春 《结直肠肛门外科》 2007年第4期223-224,共2页
目的:评价CONTOUR在双吻合器技术中的作用。方法:回顾性分析2005年4月至2006年7月在低位直肠癌中应用的90例CONTOUR和219例XF进行双吻合器技术的比较。结果:CONTOUR组保肛率(57.8%)优于XF组(44.7%);吻合口漏、吻合口狭窄和吻合口出血等... 目的:评价CONTOUR在双吻合器技术中的作用。方法:回顾性分析2005年4月至2006年7月在低位直肠癌中应用的90例CONTOUR和219例XF进行双吻合器技术的比较。结果:CONTOUR组保肛率(57.8%)优于XF组(44.7%);吻合口漏、吻合口狭窄和吻合口出血等并发症两组无差异。结论:CONTOUR不增加并发症,能提高保肛率,是双吻合器技术中XF很好的替代产品。 展开更多
关键词 直肠肿瘤 双吻合器技术 凯途(contour)
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基于非采样Contourlet特征的水印算法 被引量:5
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作者 刘晶 刘刚 +1 位作者 李爱民 金海燕 《计算机工程》 CAS CSCD 北大核心 2009年第17期143-145,共3页
提出一种利用非采样Contourlet边缘方向信息实现对RST攻击校正的水印方案。该方案利用非采样Contourlet变换提取载体图像多尺度多方向上的变换系数,对显著方向子带系数进行二值并细化,获得载体图像轮廓方向信息。水印检测时,利用轮廓方... 提出一种利用非采样Contourlet边缘方向信息实现对RST攻击校正的水印方案。该方案利用非采样Contourlet变换提取载体图像多尺度多方向上的变换系数,对显著方向子带系数进行二值并细化,获得载体图像轮廓方向信息。水印检测时,利用轮廓方向的特征点集估计测试图像受到RST攻击的参数,从而使测试图像恢复到原来的大小和位置,即恢复已丢失的同步信息。实验结果表明,该方法对RST攻击具有较好的鲁棒性。 展开更多
关键词 非采样contourLET变换 轮廓方向系数 数字水印 二值化
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CONTOUR0.5T磁共振射频系统故障的排除 被引量:1
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作者 李雪源 杨春光 《医疗卫生装备》 CAS 2008年第9期124-124,共1页
CONTOUR 0.5T磁共振成像系统在国内装机量较大.目前该产品逐渐进入了故障多发期。现介绍1例CONTOUR 0.5TMR射频系统故障排除过程,供参考。
关键词 contour 磁共振射频系统 故障排除 磁共振成像系统 装机量
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一种由内向外的Active Contour模型图像分割算法
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作者 张辉 吴月宁 《计算机工程与应用》 CSCD 北大核心 2011年第23期171-173,共3页
针对主动轮廓模型图像分割,提出一种改进算法。该算法首先选取边界内部点为轮廓初始点,再根据能量与面积的关系,将传统算法中初始点向边界点收缩改进为由初始点向边界点膨胀。算法的实现采用原始模型和改进模型相互交替的贪婪算法,保证... 针对主动轮廓模型图像分割,提出一种改进算法。该算法首先选取边界内部点为轮廓初始点,再根据能量与面积的关系,将传统算法中初始点向边界点收缩改进为由初始点向边界点膨胀。算法的实现采用原始模型和改进模型相互交替的贪婪算法,保证了模型的稳定性特点。实验结果表明:这种由内向外的分割算法比传统模型分割效果好及适用范围广;避免了传统模型对凹陷区域分割效果不理想及边界外部复杂环境对分割效果的影响。 展开更多
关键词 ACTIVE contour模型 面积 greedy算法
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Web应用中基于不规则三角网格的Contour图绘制 被引量:1
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作者 古小敏 宋小鹏 +2 位作者 何秀锦 吴国珊 王斌武 《测绘与空间地理信息》 2021年第6期72-75,共4页
尝试在Web应用中提出基于不规则三角网格单元(TIN,Triangulated Irregular Network)的Contour算法:先生成图例Legend,再根据三角形顶点数值和等值线分布将三角形分为3类,据此把三角形进一步划分为若干区域,以填充对应颜色。同时引入基... 尝试在Web应用中提出基于不规则三角网格单元(TIN,Triangulated Irregular Network)的Contour算法:先生成图例Legend,再根据三角形顶点数值和等值线分布将三角形分为3类,据此把三角形进一步划分为若干区域,以填充对应颜色。同时引入基于硬件加速的WebGL方式绘制Contour,结果表明,基于Web GL的Contour图绘制过程CPU耗时远小于canvas方式。 展开更多
关键词 contour 不规则三角形网格 WEBGL
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Medical images application of contour extraction based on Hermite splines contour model 被引量:1
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作者 陈曾胜 周康源 +1 位作者 胡跃辉 李传富 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第6期702-706,共5页
Active Contour Model or Snake model is an efficient method by which the users can extract the object contour of Region Of Interest (ROI). In this paper, we present an improved method combining Hermite splines curve ... Active Contour Model or Snake model is an efficient method by which the users can extract the object contour of Region Of Interest (ROI). In this paper, we present an improved method combining Hermite splines curve and Snake model that can be used as a tool for fast and intuitive contour extraction. We choose Hermite splines curve as a basic function of Snake contour curve and present its energy function. The optimization of energy minimization is performed hy Dynamic Programming technique. The validation results are presented, comparing the traditional Snake model and the HSCM, showing the similar performance of the latter. We can find that HSCM can overcome the non-convex constraints efficiently. Several medical images applications illustrate that Hermite Splines Contour Model (HSCM) is more efficient than traditional Snake model. 展开更多
关键词 hermite splines contour model HSCM Snake model dynamic programming contour extraction
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Research of contour error compensation control for X-C non-circular grinding in polar coordinates 被引量:6
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作者 LI Qiguang HAN Qiushi +1 位作者 PENG Baoying WANG Hongjun 《Instrumentation》 2014年第1期29-37,共9页
In the X-C linkage grinding of non-circular parts,the computation and control method of contour error in polar coordinates platform is different with that in the XY coordinates platform.To solve this problem,the analy... In the X-C linkage grinding of non-circular parts,the computation and control method of contour error in polar coordinates platform is different with that in the XY coordinates platform.To solve this problem,the analysis of the definition and computation methods for contour error and track error in polar coordinates platform will be made.Through the relative lead-lag relation of the linkage axes in the grinding process,the range of the estimation contour error is narrowed and a contour error calculation model is constructed.Then the contour compensation controllers along contour error direction and trajectory tracking error direction are designed respectively,and the error compensation decoupling matrix of the X-C linkage axes is given as well.In the end of this paper,we take the machining of the cylinder contour in Wankel rotary piston engine as an example.A simulation experiment of contour error compensation control based on relative lead-lag quantity is made.The result shows that the designed contour compensation controller can increase the contour machining accuracy effectively. 展开更多
关键词 polar coordinates X-C grinding non-circular contour relative lead-lag contour error
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In-situ 3D contour measurement for laser powder bed fusion based on phase guidance
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作者 Yuze Zhang Pan Zhang +3 位作者 Xin Jiang Siyuan Zhang Kai Zhong Zhongwei Li 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第2期113-119,共7页
In-situ layerwise imaging measurement of laser powder bed fusion(LPBF)provides a wealth of forming and defect data which enables monitoring of components quality and powder bed homogeneity.Using high-resolution camera... In-situ layerwise imaging measurement of laser powder bed fusion(LPBF)provides a wealth of forming and defect data which enables monitoring of components quality and powder bed homogeneity.Using high-resolution camera layerwise imaging and image processing algorithms to monitor fusion area and powder bed geometric defects has been studied by many researchers,which successfully monitored the contours of components and evaluated their accuracy.However,research for the methods of in-situ 3D contour measurement or component edge warping identification is rare.In this study,a 3D contour mea-surement method combining gray intensity and phase difference is proposed,and its accuracy is verified by designed experiments.The results show that the high-precision of the 3D contours can be achieved by the constructed energy minimization function.This method can detect the deviations of common ge-ometric features as well as warpage at LPBF component edges,and provides fundamental data for in-situ quality monitoring tools. 展开更多
关键词 Laser powder bed fusion In-situ measurement Active contours 3D contour Measurement accuracy
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A Method for Generating Contour Tree Based on Voronoi Interior Adjacency
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作者 QIAO Chaofei ZHAO Renliang +1 位作者 CHEN Jun CHEN Yunhao 《Geo-Spatial Information Science》 2005年第4期287-290,310,共5页
A contour tree is a good graphical tool for representing the spatial relations of contour lines and has many applications in map generalization, map annotation, terrain analysis, etc. A new method for generating conto... A contour tree is a good graphical tool for representing the spatial relations of contour lines and has many applications in map generalization, map annotation, terrain analysis, etc. A new method for generating contour trees by introducing a Voronoi based interior adjacency concept is proposed in this paper. The immediate interior adjacency set is employed to identify all of the children contours of each contour without contour elevations. It has advantages over existing methods such as the geometric method and the region growing based method. 展开更多
关键词 spatial relations of contour lines contour tree Voronoi interior adjacency set
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Vehicle detection based on information fusion of vehicle symmetrical contour and license plate position 被引量:1
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作者 连捷 赵池航 +2 位作者 张百灵 何杰 党倩 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期240-244,共5页
An efficient vehicle detection approach is proposed for traffic surveillance images, which is based on information fusion of vehicle symmetrical contour and license plate position. The vertical symmetry axis of the ve... An efficient vehicle detection approach is proposed for traffic surveillance images, which is based on information fusion of vehicle symmetrical contour and license plate position. The vertical symmetry axis of the vehicle contour in an image is. first detected, and then the vertical and the horizontal symmetry axes of the license plate are detected using the symmetry axis of the vehicle contour as a reference. The vehicle location in an image is determined using license plate symmetry axes and the vertical and the horizontal projection maps of the vehicle edge image. A dataset consisting of 450 images (15 classes of vehicles) is used to test the proposed method. The experimental results indicate that compared with the vehicle contour-based, the license plate location-based, the vehicle texture-based and the Gabor feature-based methods, the proposed method is the best with a detection accuracy of 90.7% and an elapsed time of 125 ms. 展开更多
关键词 vehicle detection symmetrical contour license plate position information fusion
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