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51.
52.
Multi-Modal Dialog Scene Detection Using Hidden Markov Models for Content-Based Multimedia Indexing 总被引:1,自引:1,他引:0
A class of audio-visual data (fiction entertainment: movies, TV series) is segmented into scenes, which contain dialogs, using a novel hidden Markov model-based (HMM) method. Each shot is classified using both audio track (via classification of speech, silence and music) and visual content (face and location information). The result of this shot-based classification is an audio-visual token to be used by the HMM state diagram to achieve scene analysis. After simulations with circular and left-to-right HMM topologies, it is observed that both are performing very good with multi-modal inputs. Moreover, for circular topology, the comparisons between different training and observation sets show that audio and face information together gives the most consistent results among different observation sets. 相似文献
53.
Lee B Parr CS Plaisant C Bederson BB Veksler VD Gray WD Kotfila C 《IEEE transactions on visualization and computer graphics》2006,12(6):1414-1426
Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food Webs, ontologies and social networks difficult to understand and interact with. We propose a new interactive visual analytics component called TreePlus that is based on a tree-style layout. TreePlus reveals the missing graph structure with visualization and interaction while maintaining good readability. To support exploration of the local structure of the graph and gathering of information from the extensive reading of labels, we use a guiding metaphor of "plant a seed and watch it grow." It allows users to start with a node and expand the graph as needed, which complements the classic overview techniques that can be effective at (but often limited to) revealing clusters. We describe our design goals, describe the interface and report on a controlled user study with 28 participants comparing TreePlus with a traditional graph interface for six tasks. In general, the advantage of TreePlus over the traditional interface increased as the density of the displayed data increased. Participants also reported higher levels of confidence in their answers with TreePlus and most of them preferred TreePlus 相似文献
54.
We have discovered a class of fractal functions that are differentiable. Fractal interpolation functions have been used for
over a decade to generate rough functions passing through a set of given points. The integral of a fractal interpolation function
remains a fractal interpolation function, and this new fractal interpolation function is differentiable. Tensor products of
pairs of these fractal functions form fractal surfaces with a well-defined tangent plane. We use this surface normal to shade
fractal surfaces, and demonstrate its use with renderings of fractal mirrors. 相似文献
55.
Wayne Madsen 《Computer Fraud & Security》2000,2000(5):15
The Senate Judiciary Subcommittee on Technology and Terrorism held a hearing on 1 February 2000 dealing with privacy and critical infrastructure protection. The highlight of the meeting was the response given by Critical Infrastructure Assurance Office (CIAO) director John Tritak to a question by sub-committee chairman Senator Jon Kyl of Arizona. Kyl asked Tritak about concerns that the proposed Federal Intrusion Detection Network (FIDNET) would violate the spirit of wiretap laws — a point made clear in a Justice Department memo to the CIAO dated 8 March, 1999. Tritak replied that the wiretap laws only apply to voice communications, not E-mail. Marc Rotenberg of the Electronic Privacy Information Center (EPIC) later testified that this was erroneous because the Electronic Communications Privacy Act of 1986 amended the wiretap laws to cover government interception of E-mail. Tritak later admitted that his earlier testimony on wiretap authority may not have been correct. 相似文献
56.
In the intensive care unit patients benefit from being fed and from having well controlled glucose levels. Insulin and glucose infusion serves as manipulated inputs to regulate blood glucose, while glucose infusion serves as a sole nutritional input. In this paper, a model predictive control strategy, based on simultaneously manipulating glucose and insulin infusion, is developed to improve blood glucose regulation in intensive care unit patients. In the short term, glucose infusion is used for tighter glucose control, particularly for disturbance rejection, while, in the long-term (24 h period), glucose infusion is used to meet nutritional needs. The “habituating control” algorithm is proposed and tested against a model predictive control (MPC) strategy that only manipulates insulin. The simulation results indicate that the Habituating MPC strategy outperforms the single input–single output MPC by providing faster setpoint tracking and tighter glucose control for a patient population, and producing less glucose variability while rejecting disturbances in insulin infusion and insulin sensitivity. 相似文献
57.
58.
By poly(A-B) we denote a chain with repeating sequence -A-B-, such as polyoxymethylene. Here A and B stand for a single atom, e.g., -O-, or a group of atoms, e.g., -CH2-. All n bond vectors are of the same length, l, as are all bond dipole moment vectors, m. The manner in which the characteristic ratio of the dipole moment, Dn≡〈μ2〉0/nm2 approaches its asymptotic limit is related quantitatively to the behavior of subchains of various sizes in poly(A-B). Illustrative numerical calculations with rotational isomeric state (RIS) models for several polymers are consistent with the predictions. The approach of Dn to its asymptotic limit is sensitive to longer subchains than is the approach of the characteristic ratio of the end-to-end distance, Cn≡〈r2〉0/nl2, to its asymptotic limit, due to the differences in the connectivity of the bond vectors (head-to-tail) and the bond dipole moment vectors (head-to-head, tail-to-tail). 相似文献
59.
The existence of nanometer-thick amorphous equilibrium films at metal-ceramic interfaces has been experimentally verified for the Au–Al2O3 system. The films were formed using a novel experimental approach, in which thin sputtered films of Au were dewetted on a sapphire substrate which was previously partially wetted with drops of anorthite glass (CaO–2SiO2–Al2O3). High-resolution transmission electron microscopy and qualitative analytical transmission electron microscopy were used to confirm the existence of the amorphous films. In addition, positive and relatively large Hamaker constants were calculated for the Au-film-Al2O3 interface, which indicates the existence of an attractive van der Waals force which stabilizes the film, similar to equilibrium films at grain boundaries in ceramics. A ∼ 1 nm thick surface film was also detected on the (0001) surface of sapphire substrates partially wetted by anorthite glass. The refractive index required to stabilize the surface films, via a positive Hamaker constant, is explored. 相似文献
60.