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71.
In this paper, we present an integration framework for heterogeneous motion generators. The objective is to outline issues that are currently easily solved in professional post-processing systems used in film and game production but which cannot be transposed as is to real-time systems with autonomous agents. We summarise our approach for articulated agent-modelling and their animation by combining heterogeneous motion generators, such as real-time motion capturing, key-framing, inverse kinematics, procedural walking. We propose an agent/action-oriented framework. Activity properties such as action simultaneity and motion blending, spatial coherence, motion-flow update schemes, agent attachments, and location corrections, are the main topics handled by our generic animation framework. Numerous examples throughout the paper illustrate our approach and outline encountered problems and solutions or open research directions. 相似文献
72.
Nikolaj S. Bjørner Anca Browne Michael A. Colón Bernd Finkbeiner Zohar Manna Henny B. Sipma Tomás E. Uribe 《Formal Methods in System Design》2000,16(3):227-270
We review a number of formal verification techniques supported by STeP, the Stanford Temporal Prover, describing how the tool can be used to verify properties of several versions of the Bakery Mutual exclusion algorithm for mutual exclusion. We verify the classic two-process algorithm and simple variants, as well as an atomic parameterized version. The methods used include deductive verification rules, verification diagrams, automatic invariant generation, and finite-state model checking and abstraction. 相似文献
73.
What can happen if we combine the best ideas from the Social Web and Semantic Web? The Social Web is an ecosystem of participation, where value is created by the aggregation of many individual user contributions. The Semantic Web is an ecosystem of data, where value is created by the integration of structured data from many sources. What applications can best synthesize the strengths of these two approaches, to create a new level of value that is both rich with human participation and powered by well-structured information? This paper proposes a class of applications called collective knowledge systems, which unlock the “collective intelligence” of the Social Web with knowledge representation and reasoning techniques of the Semantic Web. 相似文献
74.
Robust Classification for Imprecise Environments 总被引:9,自引:0,他引:9
In real-world environments it usually is difficult to specify target operating conditions precisely, for example, target misclassification costs. This uncertainty makes building robust classification systems problematic. We show that it is possible to build a hybrid classifier that will perform at least as well as the best available classifier for any target conditions. In some cases, the performance of the hybrid actually can surpass that of the best known classifier. This robust performance extends across a wide variety of comparison frameworks, including the optimization of metrics such as accuracy, expected cost, lift, precision, recall, and workforce utilization. The hybrid also is efficient to build, to store, and to update. The hybrid is based on a method for the comparison of classifier performance that is robust to imprecise class distributions and misclassification costs. The ROC convex hull (ROCCH) method combines techniques from ROC analysis, decision analysis and computational geometry, and adapts them to the particulars of analyzing learned classifiers. The method is efficient and incremental, minimizes the management of classifier performance data, and allows for clear visual comparisons and sensitivity analyses. Finally, we point to empirical evidence that a robust hybrid classifier indeed is needed for many real-world problems. 相似文献
75.
Attempts to carry out the hydroformylation of allyldiethylamine homogeneously catalyzed by rhodium complexes led to unexpected formation of N,N,N,N-tetraethyl-1,4-diaminobutane and 4-(diethylamino)-1-butanole as final products. The role of the catalyst on the product formation and the reaction mechanism are briefly discussed. 相似文献
76.
Hoffren Anna-Marja; Saloheimo Markku; Thomas Pamela; Overington John P.; Johnson Mark S.; Knowles Jonathan K.C.; Blundell Tom L. 《Protein engineering, design & selection : PEDS》1993,6(2):177-182
A model of the lignin peroxidase LIII of Phlebia radiata wasconstructed on the basis of the structure of cytochrome c peroxidase(CCP). Because of the low percentage of amino acid identitybetween the CCP and the lignin peroxidase LIII of Phlebia radiata,alignment of the sequences was based on the generation of atemplate from a knowledge of the 3-D structure of CCP and consensussequences of lignin peroxidases. This approach gave an alignmentin which all the insertions in the lignin peroxidase were placedat loop regions of CCP, with a 21.1% identity for these twoproteins. The model was constructed using this alignment andthe computer program COMPOSER, which assembles the model asa series of rigid fragments derived from CCP and other proteins.Manual intervention was required for some of the longer loopregions. The -helices forming the structural framework, andespecially the haem environment of CCP, are conserved in theLIII model and the core is close packed without holes. A possiblesite of the substrate oxidation at the haem edge of LIII isdiscussed. 相似文献
77.
Internet and the WWW more and more play an important role in our information society. It is now one of the major sources of
information in every rank of our society. The overwhelming accessibility to data, on a global scale, does not necessarily
translate to widespread utility of data. We often find that we are drowning in data, with few tools to help managing relevant
data for our various activities. In this paper, we argue that the WWW and its end-users could benefit from the existence of
a conceptual web site schema. We propose such a conceptual web site schema that describes what information is available in
a web site and how this information is structured into pages and links. To allow to communicate this information through the
web, we developed an XML Document Type Definition (DTD) for this conceptual web site schema. We also illustrate the feasibility
of the approach by a simple application program developed using the XML Document Object Model (DOM).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
79.
Danyang Zhao Tom Wyatt Minjie Wang Allen Yi Donggang Yao 《Microsystem Technologies》2012,18(4):481-488
A flexible microfluidic chip is difficult to fabricate using the standard hot embossing technology. In this study, rubber-assisted
embossing of polymer thin films using molds with through-thickness microchannels was investigated. The polymer film was thermoformed
into the microchannels by rubber as a soft counter-tool. Different processing conditions, as well as material selections,
affecting the thickness uniformity and replicated depth were examined. Results indicated that smoother surfaces on the embossed
articles were created, and the thickness uniformity and the depth of the embossed channel were significantly affected by the
embossing temperature, the embossing pressure, and the rubber hardness. The embossed film was sealed on one side with a layer
of transparent adhesive film to form closed microchannels, and desired 3-D flow characteristics were obtained with this flexible
microfluidic chip. 相似文献
80.
Supervisory control of distributed DES with a global specification and local supervisors is a difficult problem. For global specifications, the equivalent conditions for local control synthesis to equal global control synthesis may not be met. This paper formulates and solves a control synthesis problem for a generator with a global specification and with a combination of a coordinator and local controllers. Conditional controllability is proven to be an equivalent condition for the existence of such a coordinated controller. A procedure to compute the least restrictive solution within our coordination control architecture is provided and conditions under which the result coincides with the supremal controllable sublanguage are stated. 相似文献