Home About us Contact
|
Home About us Contact | ||
|
|
||
Features Used (feature + used)
Selected AbstractsA survey on Mesh Segmentation TechniquesCOMPUTER GRAPHICS FORUM, Issue 6 2008Ariel Shamir Abstract We present a review of the state of the art of segmentation and partitioning techniques of boundary meshes. Recently, these have become a part of many mesh and object manipulation algorithms in computer graphics, geometric modelling and computer aided design. We formulate the segmentation problem as an optimization problem and identify two primarily distinct types of mesh segmentation, namely part segmentation and surface-patch segmentation. We classify previous segmentation solutions according to the different segmentation goals, the optimization criteria and features used, and the various algorithmic techniques employed. We also present some generic algorithms for the major segmentation techniques. [source] An efficient approach to texture-based image retrievalINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 5 2007Mahmoud R. Hejazi Abstract In this article, we present an efficient approach for image retrieval based on the textural information of an image, such as orientation, directionality, and regularity. For this purpose, we apply the nonlinear modified discrete Radon transform to estimate these visual contents. We then utilize texture orientation to construct the rotated Gabor transform for extraction of the rotation-invariant texture feature. The rotation-invariant texture feature, directionality, and regularity are the main features used in the proposed approach for similarity assessment. Experimental results on a large number of texture and aerial images from standard databases show that the proposed schemes for feature extraction and image retrieval significantly outperform previous works, including methods based on the MPEG-7 texture descriptors. © 2008 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 295,302, 2007 [source] On identifying marker genes from gene expression data in a neural framework through online feature analysisINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 4 2006Nikhil Ranjan Pal Many attempts have been made to analyze gene expression data. Typical goals of such analysis include discovery of subclasses, designing predictors/classifiers for diseases, identifying marker genes, and trying to get a deeper understanding of underlying biological process. Success of each of these tasks strongly depends on the features used to solve the problem. The high dimensional nature of expression profiles makes the task very difficult. Consequently, many researchers have used some feature selection criteria to reduce the dimensionality of the problem. These approaches are off-line in nature, as feature selection is done in a separate phase from the system design phase. These approaches ignore the fact that utility of features depends on both the problem that is solved and the tool that is used to solve the problem. We here propose to use a novel neural scheme that picks up the necessary features on-line when the system learns the classification task. Because it considers all the features at one go, it does not miss any subtle combination of these features. We demonstrate the effectiveness of our on-line feature selection (OFS) scheme to distinguish between acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) cancer expression data set. Our scheme could identify only five genes that can produce results as good as or even better than what is reported in the literature on this data set. It identifies an important marker gene that alone has a very good discriminating power. This analysis method is quite general in nature and can be effectively used in other areas of bioinformatics. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 453,467, 2006. [source] Effects of preservation on pigmentation and length measurements in larval lampreysJOURNAL OF FISH BIOLOGY, Issue 4 2006F. B. Neave The effects of two methods of preservation (fixation and storage in 10% formalin, and fixation in 10% formalin followed by storage in 95% alcohol) on pigmentation and morphometric features used for identification of larval Ichthyomyzon lampreys were analysed. Both short-term (3 weeks) and long-term (6 months) studies were conducted using digital analysis of images of fresh and preserved lampreys. Six standard morphometric lengths and 10 areas of pigmentation were analysed. All measurements were significantly affected by preservation. Preservative type affected pigmentation and morphometric characteristics differently, and characters were affected to different degrees. Multiple measurements over time showed that almost all changes occurred within 3 weeks of preservation. Regression equations allowed for accurate correction of preservation effects on morphometric measurements, but the effects on pigmentation levels were less predictable. Effects of preservation on larval lampreys need to be considered when comparing fresh and preserved specimens because they influence critical identification features. [source] SOCIAL NETWORKS AND CROSS-CULTURAL INTERACTION: A NEW INTERPRETATION OF THE FEMALE TERRACOTTA FIGURINES OF HELLENISTIC BABYLONOXFORD JOURNAL OF ARCHAEOLOGY, Issue 2 2007STEPHANIE M. LANGIN-HOOPER Summary. In the study of the Hellenistic period in Babylon, cross-cultural interactions between Greeks and native Babylonians have been primarily interpreted using colonialist theories of Hellenisation, domination, and cultural isolation. This paper finds, however, that such theories cannot adequately explain the types of cross-cultural combinations seen in the archaeological record of female Hellenistic Babylonian terracotta figurines. The forms and functions of these terracotta figurines were substantially altered and combined throughout the Hellenistic period, resulting in Greek-Babylonian multicultural figurines as well as figurines that exhibited new features used exclusively in Hellenistic Babylonia. In order to facilitate a greater understanding of the full complexity of these Greek,Babylonian interactions, a new interpretation of cross,cultural interaction in Hellenistic Babylon is developed in this paper. This Social Networks model provides an alternative framework for approaching both how a hybrid material culture of terracotta figurines was developed and how Hellenistic Babylon became a multicultural society. [source] THE AFFINITIES OF THE ENIGMATIC DINOSAUR ESHANOSAURUS DEGUCHIIANUS FROM THE EARLY JURASSIC OF YUNNAN PROVINCE, PEOPLE'S REPUBLIC OF CHINAPALAEONTOLOGY, Issue 4 2009PAUL M. BARRETT Abstract:,Eshanosaurus deguchiianus is based on a single left dentary from the Lower Lufeng Formation (Lower Jurassic) of Yunnan Province, China. It was originally identified as the earliest known member of Therizinosauroidea (Theropoda: Coelurosauria), a conclusion that results in a significant downward range extension for this clade (>65 million years) and for many other major lineages within Coelurosauria. However, this interpretation has been questioned and several authors have proposed that the anatomical features used to refer Eshanosaurus to Therizinosauroidea are more consistent with attribution to a basal sauropodomorph dinosaur. Detailed consideration of the holotype specimen suggests that several features of the dentary and dentition exclude Eshanosaurus from Sauropodomorpha and support its inclusion within Therizinosauroidea. If accepted as an Early Jurassic coelurosaur, Eshanosaurus has important implications for understanding the timing and tempo of early theropod diversification. Moreover, its provenance also suggests that substantial portions of the coelurosaur fossil record may be missing or unsampled. However, the Early Jurassic age of Eshanosaurus requires confirmation if this taxon is to be fully incorporated into broader evolutionary studies. [source] Ductular reaction is helpful in defining early stromal invasion, small hepatocellular carcinomas, and dysplastic nodulesCANCER, Issue 5 2007Young Nyun Park MD Abstract BACKGROUND. Stromal invasion is 1 of the main features used to distinguish high-grade dysplastic nodules (DNs) from well-differentiated hepatocellular carcinomas (HCCs). The authors hypothesized that ductular reaction (DR) takes place around noninvasive hepatocellular nodules but not within the stroma contiguous to invasive HCC. METHODS. DR/cytokeratin 7 (CK7)-positive patterns were evaluated in 105 resected small hepatic nodules according to the level of invasion. The nodules were classified histologically prior to immunostaining as noninvasive (large regenerative nodules, low-grade DNs, and high-grade DNs), minimally invasive (early HCCs with a vaguely nodular type), and overtly invasive (typical HCCs with a distinctly nodular type) in a review by expert pathologists, the current gold standard. Intranodular DR (inner DR) and DR around the nodule periphery (outer DR) were assessed separately on a semiquantitative scale from 0 to 4+. RESULTS. DR was 3 or 4+ in the majority of noninvasive nodules (inner DR, 81%; outer DR, 91%), whereas DR was 0 or 1+ in overtly invasive HCCs (inner DR, 96%; outer DR, 81%). Minimally invasive HCCs showed an intermediate DR pattern (2 or 3+ inner DR, 75%; 2+ outer DR, 67%). DR characteristically was absent at the stromal-invasive, leading edge of tumor cells in both minimally invasive HCCs (focal loss of DR/CK7) and overtly invasive HCCs (diffuse loss of DR/CK7). The DR patterns in 41 needle-biopsy samples were similar to the patterns observed in resected nodules. CONCLUSIONS. DR/CK7 immunostaining may help to identify small foci of invasion and to distinguish noninvasive, high-grade DNs from both minimally invasive and overtly invasive HCCs. Cancer 2007 © 2007 American Cancer Society. [source] | ||||||||||||||||