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Face Recognition with Region Division and Spin Images [chapter]

Yang Li, William A. P. Smith, Edwin R. Hancock
2006 Lecture Notes in Computer Science  
We commence by extracting needle-maps from gray-scale images of faces, using a mean needle-map to enforce the correct pattern of facial convexity and concavity.  ...  This paper explores how spin images can be constructed using shapefrom-shading information and used for the purposes of face recognition.  ...  The patch template is constructed from the mean facial needle map, and consists of regions that are either wholly concave or wholly convex.  ... 
doi:10.1007/11892755_11 fatcat:wcz3yudzq5br3ln35srbuv7tnu

Developing a Semantic-Driven Hybrid Segmentation Method for Point Clouds of 3D Shapes

Xiaowen Yang, Xie Han, Qingde Li, Ligang He, Min Pang, Caiqin Jia
2020 IEEE Access  
In the first stage, a new feature of point cloud, called Local Concave-Convex Histogram, is introduced to first extract saddle regions complying with the semantic boundary feature.  ...  This stage often leads to multiple over-segmentation convex regions, which are then remerged by a variational method established based on the narrow-band theory.  ...  shapes with the rich set of the concave and convex regions and high level of noise, it can be shown from Fig. 12 , the face, hat and body from the bust consist of some patches.  ... 
doi:10.1109/access.2020.2976847 fatcat:r7hj5uzusjdohgva7yxsoeyyom

A027 Development of Automatic Machining Process Deciding System Based on 3D-Model

Jiang ZHU, Saori MUTO, Tomohisa Tanaka, Yoshio SAITO
2013 Proceedings of International Conference on Leading Edge Manufacturing in 21st century LEM21  
The system analyzes the shape of a 3D-model and extracts manufacturing features considering combinations of feature regions.  ...  The system also selects cutting tool considering the shape of manufacturing features and decides machining sequence considering combinations of machining tool.  ...  Next, the system extracts manufacturing features considering concave or convex information and height information of each feature regions [5] .  ... 
doi:10.1299/jsmelem.2013.7.123 fatcat:uylbdixqszhvhd6oj5hb5i2lxu

A novel and smart interactive feature recognition system for rotational parts using a STEP file

Mazin Al-wswasi, Atanas Ivanov
2019 The International Journal of Advanced Manufacturing Technology  
Several examples have been processed for this paper to validate the system, and based on the results, it is anticipated that it will lead to the launching of a new generation of feature recognition systems  ...  The implementation of automatic feature recognition (AFR) techniques is considered an indispensable concept for transferring product data between computer-aided design (CAD) and automatic computer-aided  ...  The top level of description in this hierarchy is the shell, which is a topological item that bounds a region in 3D space by joining a number of faces along edges.  ... 
doi:10.1007/s00170-019-03849-1 fatcat:5angsegfxfbcfmr5rwykacpg3m

Unfolding an Indoor Origami World [chapter]

David Ford Fouhey, Abhinav Gupta, Martial Hebert
2014 Lecture Notes in Computer Science  
We propose the use of midlevel constraints for 3D scene understanding in the form of convex and concave edges and introduce a generic framework capable of incorporating these and other constraints.  ...  We demonstrate improvements over the state-of-the art and produce interpretations of the scene that link large planar surfaces.  ...  A subset of valid arrangements in the image plane of surfaces (colors) and convex and concave edges (black) in our scene interpretation method with a gray surface normal arrow for disambiguation. convex  ... 
doi:10.1007/978-3-319-10599-4_44 fatcat:hhb244ef75gnrdkanfn5idtdza

Machine interpretation of CAD data for manufacturing applications

Qiang Ji, Michael M. Marefat
1997 ACM Computing Surveys  
The purposes of this article are to review and summarize the development of research on machine recognition of features from CAD data, to discuss the advantages and potential problems of each approach,  ...  It can be used in CAD/CAM for evaluation of designs, in computer vision for machine recognition and machine inspection of objects, and in intelligent manufacturing for automating and integrating the link  ...  Based on these primitives, a depression is identified if convex edges are on the inner loop of a face, and, similarly, a protrusion is identified by concave edges on the inner loop of a face.  ... 
doi:10.1145/262009.262012 fatcat:zeyxraytzvf4rdkqokteb4fope

Computing global visibility maps for regions on the boundaries of polyhedra using Minkowski sums

Min Liu, Yu-shen Liu, Karthik Ramani
2009 Computer-Aided Design  
Both the self-occlusions introduced by a region and the global occlusions introduced by the rest of the surfaces on the boundary of the polyhedron are considered for computing a global visibility map.  ...  Our method has been successfully tested on many CAD models. It extends the previous methods for computing global visibility maps using convex decomposition, and it exhibits a better performance.  ...  Ravi for help with testing examples and helpful comments during our work. This material is based upon work partly supported by the National Science  ... 
doi:10.1016/j.cad.2009.03.010 fatcat:gtzzuuajjvgfvcyrtix2zzbbgq

The Crystal Structure of the BAR Domain from Human Bin1/Amphiphysin II and Its Implications for Molecular Recognition†

Eva Casal, Luca Federici, Wei Zhang, Juan Fernandez-Recio, Eva-Maria Priego, Ricardo Nuñez Miguel, James B. DuHadaway, George C. Prendergast, Ben F. Luisi, Ernest D. Laue
2006 Biochemistry  
this packing governs the curvature of a putative membrane-engaging concave face.  ...  Our calculations indicate that the Bin1BAR domain contains two potential sites for protein-protein interactions on the convex face of the dimer.  ...  The modeled insertion region is highlighted with a dashed circle. The numbers i, ii, and iii correspond to the concave, side, and convex views of the dimer, respectively.  ... 
doi:10.1021/bi060717k pmid:17059209 pmcid:PMC2572078 fatcat:c6gjocyombbi7hn5cpg2ua4wh4

COSMOS-A representation scheme for 3D free-form objects

C. Dorai, A.K. Jain
1997 IEEE Transactions on Pattern Analysis and Machine Intelligence  
We address the problem of representing and recognizing 3D free-form objects when 1) the object viewpoint is arbitrary, 2) the objects may vary in shape and complexity, and 3) no restrictive assumptions  ...  The scheme yields a meaningful and rich description useful for object recognition.  ...  ACKNOWLEDGMENTS We thank the anonymous reviewers for their thoughtful suggestions.  ... 
doi:10.1109/34.625113 fatcat:gbuzcsdes5d23fb2aiou4dfb6i

AN INTEGRATED SYSTEM FOR PROCESS-FIXTURE LAYOUT DESIGN OPTIMISATION FOR CUBICAL PARTS

Awais Khan, G Moeenuddin, A H Kazim, M S Kamran, M Asim
2019 South African Journal of Industrial Engineering  
The part feature model is created using various algorithms and the geometric reasoning approach.  ...  In this article, an integrated computer-assisted process-planning and computer-assisted fixture layout planning system is presented for the automatic generation of process and fixture maps.  ...  Concavity/convexity Figure 4: (a) Concave edge (b) Convex edge The required feature faces are now extracted and assembled by applying the above-mentioned algorithms.  ... 
doi:10.7166/30-2-2032 fatcat:meoyxkqzprazbgyi4hvkznrgoe

The leucine-rich repeat as a protein recognition motif

B Kobe
2001 Current Opinion in Structural Biology  
The structures all show significant similarities, including a curved overall shape with a parallel β sheet on the concave side and mostly helical elements on the convex side.  ...  The new structural information has increased our understanding of the structural determinants of LRR proteins and our ability to model such proteins with unknown structures, and has shed new light on how  ...  Acknowledgements We thank David S Waugh and co-workers for sharing unpublished data on the YopM protein. BK is a Wellcome Senior Research Fellow in Medical Science in Australia.  ... 
doi:10.1016/s0959-440x(01)00266-4 pmid:11751054 fatcat:rnynskt2pfcgnkufit5dfdg3se

Semantic Component Association within Object Classes Based on Convex Polyhedrons

Petra Đurović, Ivan Vidović, Robert Cupec
2020 Applied Sciences  
The proposed approach is based on the component association graph and a novel descriptor that describes the geometrical arrangement of the components.  ...  Points on the object relevant for a certain robot operation are usually determined by various physical properties of the object, such as its dimensions or weight distribution, and by the purpose of object  ...  Acknowledgments: We are especially grateful to Li Yi from Stanford University for kindly providing us the mapping between ShapeNet dataset meshes and point cloud model names and helping us with other dilemmas  ... 
doi:10.3390/app10082641 fatcat:fwnsqo6zyfhuroowlz5n7mc2si

On the Role of Graph Theory Apparatus in a CAD Modeling Kernel

Sergey Slyadnev, Alexander Malyshev, Andrey Voevodin, Vadim Turlapov
2020 Proceedings of the 30th International Conference on Computer Graphics and Machine Vision (GraphiCon 2020). Part 2  
The presented algorithms and ideas demonstrated their efficiency and accuracy in the bunch of industrial applications developed by our team.  ...  The set of topological and geometric heuristics backing the subgraph isomorphism algorithm is presented to achieve decent performance in our extensible feature recognition framework.  ...  Attributed adjacency graph (on the bottom) for a portion of a CAD model (on the top). The dashed lines represent concave dihedral angles. The solid lines represent convex dihedral angles.  ... 
doi:10.51130/graphicon-2020-2-3-70 fatcat:fcbvtybrojgi3mcdt2ok2ftqmu

Part-Based Segmentation and Modeling of Range Data by Moving Target

Roberto Pirrone
2001 Journal of Intelligent Systems  
First, the data set is partitioned in regions corresponding approximately to simple convex objects, and then single deformable models are fitted to each region.  ...  Refinements of the model can be achieved by recursively applying the method.  ...  In case of poor fitting, the algorithm can be applied repeatedly both to find new convex segments and to recover a better model for a single part. The rest of the paper is arranged as follows.  ... 
doi:10.1515/jisys.2001.11.4.217 fatcat:4ood5rbfgncxxbhgt6x23b2hia

3D Surface Reconstruction and Analysis in Automated Apple Stem-End/Calyx Identification

L. Jiang, B. Zhu, X. Cheng, Y. Luo, Y. Tao
2009 American Society of Agricultural and Biological Engineers. Transactions  
After successfully obtaining 3D information, a quadratic facet model was introduced to conduct the 3D concave shape fitting such that the identification of apple stem-ends and calyxes could be achieved  ...  Samples of the reconstructed 3D apple surface maps as well as the identified stem-ends/calyxes were shown in the results, and an overall 90.15% detection rate was achieved, compared to the 58.62% detection  ...  Abby Vogel for her critical reading of the manuscript.  ... 
doi:10.13031/2013.29118 fatcat:q4kkjmip4zcjjkgbrcijknaxpa
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