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991.
Low-cost telepresence for collaborative virtual environments 总被引:1,自引:0,他引:1
Rhee SM Ziegler R Park J Naef M Gross M Kim MH 《IEEE transactions on visualization and computer graphics》2007,13(1):156-166
We present a novel low-cost method for visual communication and telepresence in a CAVEtrade-like environment, relying on 2D stereo-based video avatars. The system combines a selection of proven efficient algorithms and approximations in a unique way, resulting in a convincing stereoscopic real-time representation of a remote user acquired in a spatially immersive display. The system was designed to extend existing projection systems with acquisition capabilities requiring minimal hardware modifications and cost. The system uses infrared-based image segmentation to enable concurrent acquisition and projection in an immersive environment without a static background. The system consists of two color cameras and two additional b/w cameras used for segmentation in the near-IR spectrum. There is no need for special optics as the mask and color image are merged using image-warping based on a depth estimation. The resulting stereo image stream is compressed, streamed across a network, and displayed as a frame-sequential stereo texture on a billboard in the remote virtual environment 相似文献
992.
993.
Li YF Polgar O Okada M Esser L Bates SE Xia D 《Journal of molecular graphics & modelling》2007,25(6):837-851
The ATP-binding cassette protein ABCG2 is a member of a broad family of ABC transporters with potential clinical importance as a mediator of multidrug resistance. We carried out a homology and knowledge-based, and mutationally improved molecular modeling study to establish a much needed structural framework for the protein, which could serve as guidance for further genetic, biochemical, and structural analyses. Based on homology with known structures of both full-length and nucleotide-binding domains (NBD) of ABC transporters and structural knowledge of integral membrane proteins, an initial model of ABCG2 was established. Subsequent refinement to conform to the lipophilic index distributions in the transmembrane domain (TMD) and to the results of site-directed mutagenesis experiments led to an improved model. The complete ABCG2 model consists of two identical subunits facing each other in a closed conformation. The dimeric interface in the nucleotide-binding domain (NBD) involves a characteristic nucleotide sandwich and the interface in the TMD consists of the TM helices 1–3 of one subunit and the helices 5 and 6 of the other. The interface between the NBD and the TMD is bridged by the conserved structural motif between TM2 and TM3, the intracellular domain 1 (ICD1), and the terminal β-strand (S6) of the central β-sheet in the NBD. The apparent flexibility of the ICD1 may play a role in transmitting conformational changes from the NBD to the TMD or from the TMD to the NBD. 相似文献
994.
995.
Michel F Deines E Hering-Bertram M Garth C Hagen H 《IEEE transactions on visualization and computer graphics》2007,13(6):1680-1687
Acoustic quality in room acoustics is measured by well defined quantities, like definition, which can be derived from simulated impulse response filters or measured values. These take into account the intensity and phase shift of multiple reflections due to a wave front emanating from a sound source. Definition (D50) and clarity (C50) for example correspond to the fraction of the energy received in total to the energy received in the first 50 ms at a certain listener position. Unfortunately, the impulse response measured at a single point does not provide any information about the direction of reflections, and about the reflection surfaces which contribute to this measure. For the visualization of room acoustics, however, this information is very useful since it allows to discover regions with high contribution and provides insight into the influence of all reflecting surfaces to the quality measure. We use the phonon tracing method to calculate the contribution of the reflection surfaces to the impulse response for different listener positions. This data is used to compute importance values for the geometry taking a certain acoustic metric into account. To get a visual insight into the directional aspect, we map the importance to the reflecting surfaces of the geometry. This visualization indicates which parts of the surfaces need to be changed to enhance the chosen acoustic quality measure.We apply our method to the acoustic improvement of a lecture hall by means of enhancing the overall speech comprehensibility (clarity) and evaluate the results using glyphs to visualize the clarity (C50) values at listener positions throughout the room. 相似文献
996.
Fernández M Caballero J Fernández L Abreu JI Garriga M 《Journal of molecular graphics & modelling》2007,26(4):748-759
Development of novel computational approaches for modeling protein properties is a main goal in applied Proteomics. In this work, we reported the extension of the radial distribution function (RDF) scores formalism to proteins for encoding 3D structural information with modeling purposes. Protein-RDF (P-RDF) scores measure spherical distributions on protein 3D structure of 48 amino acids/residues properties selected from the AAindex data base. P-RDF scores were tested for building predictive models of the change of thermal unfolding Gibbs free energy change (DeltaDeltaG) of chymotrypsin inhibitor 2 upon mutations. In this sense, an ensemble of Bayesian-Regularized Genetic Neural Networks (BRGNNs) yielded an optimum nonlinear model for the conformational stability. The ensemble predictor described about 84% and 70% variance of the data in training and test sets, respectively. 相似文献
997.
998.
ManyEyes: a site for visualization at internet scale 总被引:1,自引:0,他引:1
Viegas FB Wattenberg M van Ham F Kriss J McKeon M 《IEEE transactions on visualization and computer graphics》2007,13(6):1121-1128
We describe the design and deployment of Many Eyes, a public web site where users may upload data, create interactive visualizations, and carry on discussions. The goal of the site is to support collaboration around visualizations at a large scale by fostering a social style of data analysis in which visualizations not only serve as a discovery tool for individuals but also as a medium to spur discussion among users. To support this goal, the site includes novel mechanisms for end-user creation of visualizations and asynchronous collaboration around those visualizations. In addition to describing these technologies, we provide a preliminary report on the activity of our users. 相似文献
999.
Visualization of heterogeneous data 总被引:1,自引:0,他引:1
1000.
Of the common cancers, pancreatic ductal adenocarcinoma is one of the most lethal. The cancer's aggressive biology, leading to rapid dissemination, combined with a lack of clearly recognisable symptoms means that for many patients, the disease is at an advanced stage when diagnosed. The prognosis is consequently very poor, with as few as 3-5% of patients surviving 5?years. Recently, proteomic technologies have been employed in an effort to identify protein biomarkers, therapeutic targets and disease response markers for pancreatic cancer. Research has primarily relied upon pancreatic tissue samples, and body fluids such as pancreatic juice and blood serum. In this article, we will highlight the current proteomic techniques, qualitative and quantitative, employed in the field of pancreatic cancer research. We will review both the progress made and the challenges ahead, in elaborating the biology of pancreatic cancer and identifying novel biomarkers. 相似文献