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Approach Suitable (approach + suitable)
Selected AbstractsInhomogeneous volumetric Laplacian deformation for rhinoplasty planning and simulation systemCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2010Sheng-hui Liao Abstract This paper presents an intuitive rhinoplasty planning and simulation system, to provide high quality prediction of postoperative appearance, and design patient specific nose prosthesis automatically. The key component is a novel volumetric Laplacian deformation tool inspired by the state-of-the-art differential surface deformation techniques. Working on the volumetric domain and incorporating inhomogeneous material from CT data make the new approach suitable for soft tissue simulation. In particular, the system employs a special sketch contour driving deformation interface, which can provide realistic 3D rhinoplasty simulation with intuitive and straightforward 2D manipulation. When satisfied with the appearance, the change of soft tissue before and after simulation is utilized to generate the individual prosthesis model automatically. Clinical validation using post-operative CT data demonstrated that the system can provide prediction results of high quality. And the surgeons who used the system confirmed that this planning system is attractive and has potential for daily clinical practice. Copyright © 2010 John Wiley & Sons, Ltd. [source] A combined rh -adaptive scheme based on domain subdivision.INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 3 2001Formulation, linear examples Abstract An adaptive scheme is proposed in which the domain is split into two subdomains. One subdomain consists of regions where the discretization is refined with an h -adaptive approach, whereas in the other subdomain node relocation or r -adaptivity is used. Through this subdivision the advantageous properties of both remeshing strategies (accuracy and low computer costs, respectively) can be exploited in greater depth. The subdivision of the domain is based on the formulation of a desired element size, which renders the approach suitable for coupling with various error assessment tools. Two-dimensional linear examples where the analytical solution is known illustrate the approach. It is shown that the combined rh -adaptive approach is superior to its components r - and h -adaptivity, in that higher accuracies can be obtained compared to a purely r -adaptive approach, while the computational costs are lower than that of a purely h -adaptive approach. As such, a more flexible formulation of adaptive strategies is given, in which the relative importance of attaining a pre-set accuracy and speeding-up the computational process can be set by the user. Copyright © 2001 John Wiley & Sons, Ltd. [source] A new image sharpening approach for single-sensor digital cameras,INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 3 2007Rastislav Lukac Abstract This article introduces a new image sharpening approach suitable for single-sensor digital cameras equipped with a Bayer color filter array (CFA). The proposed solution firstly enhances the structural content of the captured CFA image data. Subsequent demosaicking of the enhanced CFA image data produces a visually pleasing full-color image which is noticeably sharper compared to the output of the traditional imaging pipeline. Results reported in this work suggest a three-fold processing cost reduction when the new approach is followed. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 123,131, 2007 [source] Ranking of alternatives with ordered weighted averaging operatorsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 5 2004M. Teresa Lamata Multiattribute decision making is an important part of the decision process for both individual and group problems. We incorporate the fuzzy set theory and the basic nature of subjectivity due to ambiguity to achieve a flexible decision approach suitable for uncertain and fuzzy environments. Let us consider the analytic hierarchy process (AHP) in which the labels are structured as fuzzy numbers. To obtain the scoring that corresponds to the best alternative or the ranking of the alternatives, we need to use a total order for the fuzzy numbers involved in the problem. In this article, we consider a definition of such a total order, which is based on two subjective aspects: the degree of optimism/pessimism reflected with the ordered weighted averaging (OWA) operators. A numerical example is given to illustrate the approach. © 2004 Wiley Periodicals, Inc. [source] Nonlinear wave function expansions: A progress reportINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 15 2007Ron Shepard Abstract Some recent progress is reported for a novel nonlinear expansion form for electronic wave functions. This expansion form is based on spin eigenfunctions using the Graphical Unitary Group Approach and the wave function is expanded in a basis of product functions, allowing application to closed and open shell systems and to ground and excited electronic states. Each product basis function is itself a multiconfigurational expansion that depends on a relatively small number of nonlinear parameters called arc factors. Efficient recursive procedures for the computation of reduced one- and two-particle density matrices, overlap matrix elements, and Hamiltonian matrix elements result in a very efficient computational procedure that is applicable to very large configuration state function (CSF) expansions. A new energy-based optimization approach is presented based on product function splitting and variational recombination. Convergence of both valence correlation energy and dynamical correlation energy with respect to the product function basis dimension is examined. A wave function analysis approach suitable for very large CSF expansions is presented based on Shavitt graph node density and arc density. Some new closed-form expressions for various Shavitt Graph and Auxiliary Pair Graph statistics are presented. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [source] Lempel-Ziv compression of highly structured documentsJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 4 2007Joaquín Adiego The authors describe Lempel-Ziv to Compress Structure (LZCS), a novel Lempel,Ziv approach suitable for compressing structured documents. LZCS takes advantage of repeated substructures that may appear in the documents, by replacing them with a backward reference to their previous occurrence. The result of the LZCS transformation is still a valid structured document, which is human-readable and can be transmitted by ASCII channels. Moreover, LZCS transformed documents are easy to search, display, access at random, and navigate. In a second stage, the transformed documents can be further compressed using any semistatic technique, so that it is still possible to do all those operations efficiently; or with any adaptive technique to boost compression. LZCS is especially efficient in the compression of collections of highly structured data, such as extensible markup language (XML) forms, invoices, e-commerce, and Web-service exchange documents. The comparison with other structure-aware and standard compressors shows that LZCS is a competitive choice for these type of documents, whereas the others are not well-suited to support navigation or random access. When joined to an adaptive compressor, LZCS obtains by far the best compression ratios. [source] First approach of a methodological set-up for selenomethionine chiral speciation in breast and formula milk using high-performance liquid chromatography coupled to atomic fluorescence spectroscopyAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2007J. L. Gómez-Ariza Abstract The chiral speciation of selenomethionine in breast and formula milk based on species separation by high-performance liquid chromatography followed by online microwave-assisted digestion and detection with hydride generation atomic fluorescence spectrometry (HPLC-MAD-HG-AFS) requires severe sample manipulation to avoid matrix influence. Sample clean-up for fat and protein elimination using centrifugation and ultrafiltration was optimized, and selenomethionine preconcentration based on cation exchange solid-phase extraction was studied and optimized. The resulting procedure is suitable for chiral selenium speciation in infant milk with detection limits of 3.1 and 3.5 ng ml,1 as Se for L -selenomethionine and D -selenomethionine, respectively. The time necessary for the analysis, about 90 min, including sample clean-up, analyte preconcentration and chromatographic separation, makes the approach suitable for routine analysis. Copyright © 2007 John Wiley & Sons, Ltd. [source] NMR Spectroscopy of Paramagnetic MetalloproteinsCHEMBIOCHEM, Issue 9 2005Ivano Bertini Prof. Abstract This article deals with the solution structure determination of paramagnetic metalloproteins by NMR spectroscopy. These proteins were believed not to be suitable for NMR investigations for structure determination until a decade ago, but eventually novel experiments and software protocols were developed, with the aim of making the approach suitable for the goal and as user-friendly and safe as possible. In the article, we also give hints for the optimization of experiments with respect to each particular metal ion, with the aim of also providing a handy tool for nonspecialists. Finally, a section is dedicated to the significant progress made on13C direct detection, which reduces the negative effects of paramagnetism and may constitute a new chapter in the whole field of NMR spectroscopy. [source] Error estimation of closed-form solution for annual rate of structural collapseEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 15 2008Brendon A. Bradley Abstract With the increasing emphasis of performance-based earthquake engineering in the engineering community, several investigations have been presented outlining simplified approaches suitable for performance-based seismic design (PBSD). Central to most of these PBSD approaches is the use of closed-form analytical solutions to the probabilistic integral equations representing the rate of exceedance of key performance measures. Situations where such closed-form solutions are not appropriate primarily relate to the problem of extrapolation outside of the region in which parameters of the closed-form solution are fit. This study presents a critical review of the closed-form solution for the annual rate of structural collapse. The closed-form solution requires the assumptions of lognormality of the collapse fragility and power model form of the ground motion hazard, of which the latter is more significant regarding the error of the closed-form solution. Via a parametric study, the key variables contributing to the error between the closed-form solution and solution via numerical integration are illustrated. As these key variables cannot be easily measured, it casts doubt on the use of such closed-form solutions in future PBSD, especially considering the simple and efficient nature of using direct numerical integration to obtain the solution. Copyright © 2008 John Wiley & Sons, Ltd. [source] Magnetic resonance imaging as a tool for in vivo and ex vivo anatomical phenotyping in experimental genetic modelsHUMAN BRAIN MAPPING, Issue 6 2007Alain Pitiot Abstract This article describes a suite of computational approaches suitable for deriving various quantitative phenotypes from structural magnetic resonance (MR) images obtained in rodents and used subsequently in genetic studies of complex traits. We begin by introducing the basic principles of genetic studies of complex traits in experimental models. We then illustrate the use of MR-based computational anatomy in vivo and ex vivo, and in combination with histology. This work was carried out in two inbred strains of rats, namely spontaneously hypertensive rats and Brown Norway rats; these are parental strains of the only existing panel of recombinant inbred strains of rats. The rats were scanned in vivo at two time points (at 8 and 12 weeks of age) and ex vivo (at 12 weeks of age). We describe between-strain differences and across-time changes in brain and kidney volumes, as well as regional variations in brain structure using surface- and deformation-based approaches. We conclude by discussing the power of the population-based computational analysis of MR images, and their fusion with histology, in studies of complex traits. Hum Brain Mapp, 2007. © 2007 Wiley-Liss, Inc. [source] Edge-adaptive color interpolation for complementary color filter arrayINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 3 2006Young Seok Han Abstract Complementary color filter array (CCFA) is widely used in consumer-level digital video cameras, since it not only has high sensitivity and good signal-to-noise ratio in low-light condition but also is compatible with the interlaced scanning used in broadcast systems. However, the full-color images obtained from CCFA suffer from the color artifacts such as false color and zipper effects. These artifacts can be removed with edge-adaptive color interpolation (ECI) approaches which are generally used in primary color filter array (PCFA). Unfortunately, the unique array pattern of CCFA makes it difficult that CCFA adopts ECI approaches. Therefore, to apply ECI approaches suitable for CCFA to color interpolation is one of the major issues to reconstruct the full-color images. In this paper, we propose a new ECI algorithm for CCFA. To estimate an edge direction precisely and enhance the quality of the reconstructed image, a function of spatial variances is used as a weight, and new color conversion matrices are presented for considering various edge directions. Experimental results indicate that the proposed algorithm outperforms the conventional method with respect to both objective and subjective criteria. © 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 16, 92,102, 2006 [source] Applying a continua landscape approach to evaluate plant response to fragmentation: Primula vulgaris in the Cantabrian mountainsAPPLIED VEGETATION SCIENCE, Issue 4 2009Alicia Valdés Abstract Question: Continua landscape approaches conceptualize the effects of habitat fragmentation on the biota by considering fragmented landscapes as continuous gradients, departing from the view of habitat as either suitable (fragment) or unsuitable (matrix). They also consider the ecological gradients or the ,Umwelt' (species-specific perception of the landscape) to represent the processes that ultimately limit organisms' ability to colonize and persist within habitat remnants. Are these approaches suitable for evaluating the response of plant species to fragmentation? Location: Fragmented mid-elevation temperate forests, Cantabrian range, Spain. Methods: The presence, abundance and demographic structure of populations of the perennial herb Primula vulgaris were sampled across a continuous extent of 100 ha, subdivided into 400 50 m × 50 m sampling units. These variables were related to forest availability, forest subdivision and edge density, topography and the spatial clumpiness of populations (a measure of plant dispersal constraints and, hence, a major surrogate of plant Umwelt). Results: Fragmentation processes, especially habitat loss, negatively affect P. vulgaris, with a stronger effect on presence than on abundance and demography. Despite the importance of habitat availability, P. vulgaris does not occupy all potentially suitable forest habitat, mostly owing to dispersal constraints. A positive effect of slope on plant presence also suggests some effect of habitat quality in determining establishment and occupancy of forest landscape. Conclusions: Within-habitat dispersal constraints are as important as forest fragmentation in determining the landscape-scale distribution of P. vulgaris. By assessing the relative role of the diverse fragmentation processes, and of the species' landscape perception, a continua landscape approach proves to be a valuable tool for predicting plant response to landscape change. [source] | ||||||||||||||||