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91.
92.
This paper presents a new morphing method based on the "as-rigid-as-possible" approach.Unlike the original as-rigid-as-possible method,we avoid the need to construct a consistent tetrahedral mesh,but instead require a consistent triangle surface mesh and from it create a tetrahedron for each surface triangle.Our new approach has several significant advantages.It is much easier to create a consistent triangle mesh than to create a consistent tetrahedral mesh.Secondly,the equations arising from our approach can be solved much more efficiently than the corresponding equations for a tetrahedral mesh.Finally,by incorporating the translation vector in the energy functional controlling interpolation,our new method does not need the user to arbitrarily fix any vertex to obtain a solution,allowing artists automatic control of interpolated mesh positions. 相似文献
93.
Ralph VigneAuthor Vitae Juergen ManglerAuthor Vitae Erich Schikuta Author VitaeStefanie Rinderle-Ma Author Vitae 《Future Generation Computer Systems》2012,28(1):48-57
Creating simple marketplaces with common rules, that enable the dynamic selection and consumption of functionality, is the missing link to allow small businesses to enter the cloud, not only as consumers, but also as vendors. In this paper, we present the concepts behind a hybrid service and process repository that can act as the foundation for such a marketplace, as well as a prototype that allowed us to test various real-world scenarios. The advantage of a hybrid service and process repository is that, it not only holds a flat list of services, but also exposes a generic set of use cases, that it obtains information on how specific services can be used to implement the use cases as well as information to select services at run-time according to customer’s goal functions. 相似文献
94.
Easy editing of a clothed 3D human avatar is central to many practical applications. However, it is easy to produce implausible, unnatural looking results, since subtle reshaping or pose alteration of avatars requires global consistency and agreement with human anatomy. Here, we present a parametric editing system for a clothed human body, based on use of a revised SCAPE model. We show that the parameters of the model can be estimated directly from a clothed avatar, and that it can be used as a basis for realistic, real-time editing of the clothed avatar mesh via a novel 3D body-aware warping scheme. The avatar can be easily controlled by a few semantically meaningful parameters, 12 biometric attributes controlling body shape, and 17 bones controlling pose. Our experiments demonstrate that our system can interactively produce visually pleasing results. 相似文献
95.
Cullen RH Smarr CA Serrano-Baquero D McBride SE Beer JM Rogers WA 《Applied ergonomics》2012,43(6):1122-1130
The design of and training for complex systems requires in-depth understanding of task demands imposed on users. In this project, we used the knowledge engineering approach (Bowles et al., 2004) to assess the task of mowing in a citrus grove. Knowledge engineering is divided into four phases: (1) Establish goals. We defined specific goals based on the stakeholders involved. The main goal was to identify operator demands to support improvement of the system. (2) Create a working model of the system. We reviewed product literature, analyzed the system, and conducted expert interviews. (3) Extract knowledge. We interviewed tractor operators to understand their knowledge base. (4) Structure knowledge. We analyzed and organized operator knowledge to inform project goals. We categorized the information and developed diagrams to display the knowledge effectively. This project illustrates the benefits of knowledge engineering as a qualitative research method to inform technology design and training. 相似文献
96.
Metrics for shot boundary detection in digital video sequences 总被引:5,自引:0,他引:5
The detection of shot boundaries in video sequences is an important task for generating indexed video databases. This paper
provides a comprehensive quantitative comparison of the metrics that have been applied to shot boundary detection. In addition,
several standardized statistical tests that have not been applied to this problem, as well as three new metrics, are considered.
A mathematical framework for quantitatively comparing metrics is supplied. Experimental results based on a video database
containing 39,000 frames are included. 相似文献
97.
Fast and effective feature-preserving mesh denoising 总被引:6,自引:0,他引:6
Sun X Rosin P Martin R Langbein F 《IEEE transactions on visualization and computer graphics》2007,13(5):925-938
We present a simple and fast mesh denoising method, which can remove noise effectively, while preserving mesh features such as sharp edges and corners. The method consists of two stages. Firstly, noisy face normals are filtered iteratively by weighted averaging of neighboring face normals. Secondly, vertex positions are iteratively updated to agree with the denoised face normals. The weight function used during normal filtering is much simpler than that used in previous similar approaches, being simply a trimmed quadratic. This makes the algorithm both fast and simple to implement. Vertex position updating is based on the integration of surface normals using a least-squares error criterion. Like previous algorithms, we solve the least-squares problem by gradient descent, but whereas previous methods needed user input to determine the iteration step size, we determine it automatically. In addition, we prove the convergence of the vertex position updating approach. Analysis and experiments show the advantages of our proposed method over various earlier surface denoising methods. 相似文献
98.
Reed Homer B. C. Jr.; Reitan Ralph M.; K?Ove Hallgrim 《Canadian Metallurgical Quarterly》1965,29(3):247
50 brain-damaged children ranging in age from 10 through 14 years were matched in pairs with 50 normally functioning children on the variable of age. Each subject was administered individually a wide variety of psychological tests. The sensitivity of each test to the brain-damage factor was determined by computing the appropriate t ratio and by determining the proportion of cases in which the brain-damaged children performed less adequately than their matched controls. The brain-damaged children performed significantly less well than the control children on all the tests, with differences between the 2 groups occurring more frequently on the tests of language functions than on other testing procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Effects of moving the center''s in an RBF network 总被引:1,自引:0,他引:1
Panchapakesan C. Palaniswami M. Ralph D. Manzie C. 《Neural Networks, IEEE Transactions on》2002,13(6):1299-1307
In radial basis function (RBF) networks, placement of centers is said to have a significant effect on the performance of the network. Supervised learning of center locations in some applications show that they are superior to the networks whose centers are located using unsupervised methods. But such networks can take the same training time as that of sigmoid networks. The increased time needed for supervised learning offsets the training time of regular RBF networks. One way to overcome this may be to train the network with a set of centers selected by unsupervised methods and then to fine tune the locations of centers. This can be done by first evaluating whether moving the centers would decrease the error and then, depending on the required level of accuracy, changing the center locations. This paper provides new results on bounds for the gradient and Hessian of the error considered first as a function of the independent set of parameters, namely the centers, widths, and weights; and then as a function of centers and widths where the linear weights are now functions of the basis function parameters for networks of fixed size. Moreover, bounds for the Hessian are also provided along a line beginning at the initial set of parameters. Using these bounds, it is possible to estimate how much one can reduce the error by changing the centers. Further to that, a step size can be specified to achieve a guaranteed, amount of reduction in error. 相似文献
100.
An Algorithm that Learns What's in a Name 总被引:8,自引:0,他引:8
In this paper, we present IdentiFinderTM, a hidden Markov model that learns to recognize and classify names, dates, times, and numerical quantities. We have evaluated the model in English (based on data from the Sixth and Seventh Message Understanding Conferences [MUC-6, MUC-7] and broadcast news) and in Spanish (based on data distributed through the First Multilingual Entity Task [MET-1]), and on speech input (based on broadcast news). We report results here on standard materials only to quantify performance on data available to the community, namely, MUC-6 and MET-1. Results have been consistently better than reported by any other learning algorithm. IdentiFinder's performance is competitive with approaches based on handcrafted rules on mixed case text and superior on text where case information is not available. We also present a controlled experiment showing the effect of training set size on performance, demonstrating that as little as 100,000 words of training data is adequate to get performance around 90% on newswire. Although we present our understanding of why this algorithm performs so well on this class of problems, we believe that significant improvement in performance may still be possible. 相似文献