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1.
Authoring SMIL documents by direct manipulations during presentation   总被引:1,自引:0,他引:1  
Jourdan  Muriel  Roisin  Cécile  Tardif  Laurent  Villard  Lionel 《World Wide Web》1999,2(4):179-190
This paper presents SmilEditor – an authoring environment to write multimedia documents encoded in SMIL. The main feature of SmilEditor is to strongly integrate the presentation view, in which the document is executed, with the editing process. In this view objects can be selected to perform a wide set of editing actions ranging from attributes setting to direct spatial or temporal editions. This way of editing a multimedia document is close to the wellknown WYSIWYG paradigm used by usual wordprocessors. Moreover, in order to help the author to specify the temporal organisation of documents, SmilEditor provides an execution report displayed through a timeline view. This view also contains information which helps the author to understand why such execution occurred. These multiple and synchronised views aim at covering the various needs for authoring multimedia documents.  相似文献   

2.
One major task in requirements specification is to capture the rules relevant to the problem at hand. Declarative, rule-based approaches have been suggested by many researchers in the field. However, when it comes to modeling large systems of rules, not only for the behavior of the computer system but also for the organizational environment surrounding it, current approaches have problems with limited expressiveness, flexibility, and poor comprehensibility. Hence, rule-based approaches may benefit from improvements in two directions: (1) improvement of the rule languages themselves and (2) better integration with other, complementary modeling approaches.In this article, both issues are addressed in an integrated manner. The proposal is presented in the context of the Tempora project on rule-based information systems development, but has also been integrated with PPP. Tempora has provided a rule language based on an executable temporal logic working on top of a temporal database. The rule language is integrated with static (ER-like) and dynamic (SA/RT-like) modeling approaches. In the current proposal, the integration with complementary modeling approaches is extended by including organization modeling (actors, roles), and the expressiveness of the rule language is increased by introducing deontic operators and rule hierarchies. The main contribution of the article is not seen as any one of the above-mentioned extensions, but as the resulting comprehensive modeling support. The approach is illustrated by examples taken from an industrial case study done in connection with Tempora.C. List of Symbols Subset of set - Not subset of set - Element of set - Not element of set - Equivalent to - Not equivalent to - ¬ Negation - Logical and - Logical or - Implication - Sometime in past - Sometime in future - Always in past - Always in future - Just before - Just after - u Until - s Since - Trigger - Condition - s State condition - Consequence - a Action - s State - Role - Actor - ¬ - General deontic operator - O Obligatory - R Recommended - P Permitted - D Discouraged - F Forbidden - (/–) General rule - t R Real time - t M Model time  相似文献   

3.
Multimedia synchronization involving independent sources is a challenging issue imposed by the distributed multimedia applications. In our work, this issue is studied by investigating the teleorchestra application (remote multimedia presentation). In teleorchestration, among the data objects to be presented, relative and uncertain temporal requirements may be involved. Fuzzy presentation scenarios are thus generated. In this paper, we describe a temporal model that can handle these fuzzy scenarios that contain imprecise synchronization constraints, such as unknown object presentation durations and relative event occurring times. The model supports a distributed synchronization algorithm that can schedule the independent sources for the multimedia teleorchestration.  相似文献   

4.
Summary We propose and compare two induction principles called always and sometime for proving inevitability properties of programs. They are respective formalizations and generalizations of Floyd invariant assertions and Burstall intermittent assertions methods for proving total correctness of sequential programs whose methodological advantages or disadvantages have been discussed in a number of previous papers. Both principles are formalized in the abstract setting of arbitrary nondeterministic transition systems and illustrated by appropriate examples. The sometime method is interpreted as a recursive application of the always method. Hence always can be considered as a special case of sometime. These proof methods are strongly equivalent in the sense that a proof by one induction principle can be rewritten into a proof by the other one. The first two theorems of the paper show that an invariant for the always method can be translated into an invariant for the sometime method even if every recursive application of the later is required to be of finite length. The third and main theorem of the paper shows how to translate an invariant for the sometime method into an invariant for the always method. It is emphasized that this translation technique follows the idea of transforming recursive programs into iterative ones. Of course, a general translation technique does not imply that the original sometime invariant and the resulting always invariant are equally understandable. This is illustrated by an example.  相似文献   

5.
In this paper, we define what we call a unitary immersion of a nonlinear system. We observe that, for classical Hamiltonian systems, this notion contains, in some sense, the concept of quantization. We restrict our attention to degree-zero unitary immersions, where all observation functions must be represented by operators of the type multiplication by a function. We show that the problem of classifying such degree-zero unitary immersions of a given nonlinear system is not obvious. In some cases, we solve this problem.Chargé de Recherche au CNRS.Maître de Conférences.  相似文献   

6.
The proofs of the Church–Rosser theorems for , , and reduction in untyped -calculus are formalized in Isabelle/HOL, an implementation of Higher Order Logic in the generic theorem prover Isabelle. For -reduction, both the standard proof and Takahashi's are given and compared. All proofs are based on a general theory of commutating relations that supports an almost geometric style of reasoning about confluence diagrams.  相似文献   

7.
Concurrency control issues in nested transactions   总被引:3,自引:0,他引:3  
The concept of nested transactions offers more decomposable execution units and finer-grained control over concurrency and recovery than flat transactions. Furthermore, it supports the decomposition of a unit of work into subtasks and their appropriate distribution in a computer system as a prerequisite of intratransaction parallelism. However, to exploit its full potential, suitable granules of concurrency control as well as access modes for shared data are necessary. In this article, we investigate various issues of concurrency control for nested transactions. First, the mechanisms for cooperation and communication within nested transactions should not impede parallel execution of transactions among parent and children or among siblings. Therefore, a model for nested transactions is proposed allowing for effective exploitation of intra-transaction parallelism. Starting with a set of basic locking rules, we introduce the concept of downward inheritance of locks to make data manipulated by a parent available to its children. To support supervised and restricted access, this concept is refined to controlled downward inheritance. The initial concurrency control scheme was based on S-X locks for flat, non-overlapping data objects. In order to adjust this scheme for practical applications, a set of concurrency control rules is derived for generalized lock modes described by a compatibility matrix. Also, these rules are combined with a hierarchical locking scheme to improve selective access to data granules of varying sizes. After having tied together both types of hierarchies (transaction and object), it can be shown how controlled downward inheritance for hierarchical objects is achieved in nested transactions. Finally, problems of deadlock detection and resolution in nested transactions are considered.  相似文献   

8.
It is shown that the translation of an open default into a modal formula x(L(x)LM 1 (x)...LM m (x)w(x)) gives rise to an embedding of open default systems into non-monotonic logics.  相似文献   

9.
Summary A new hybrid analytic framework, based on the principle of maximum entropy, is used to derive a closed form expression for the queue length distribution of a G/G/1 finite capacity queue. It is shown that Birth-Death homogeneous recursions for a single resource queue are special cases of maximum entropy one-step transitions which can be applied either in an operational or stochastic context. Furthermore, an equivalence relationship is used to analyse two-stage cyclic queueing networks with general service times, and favourable comparisons are made with global balance and approximate results. Numerical examples provide useful information on how critically system behaviour is affected by the distributional form of interarrival and service patterns. Comments on the implication of the work to the performance analysis and aggregation of computer systems are included.Some of the material included in this paper has been presented to the Performance '86 and ACM Sigmetrics 1986 Joint Conference on Computer Modelling, Measurement and Evaluation, May 28–30, 1986, University of North Carolina, USA  相似文献   

10.
Harnad's proposed robotic upgrade of Turing's Test (TT), from a test of linguistic capacity alone to a Total Turing Test (TTT) of linguisticand sensorimotor capacity, conflicts with his claim that no behavioral test provides even probable warrant for attributions of thought because there is no evidence of consciousness besides private experience. Intuitive, scientific, and philosophical considerations Harnad offers in favor of his proposed upgrade are unconvincing. I agree with Harnad that distinguishing real from as if thought on the basis of (presence or lack of) consciousness (thus rejecting Turing (behavioral) testing as sufficient warrant for mental attribution)has the skeptical consequence Harnad accepts — there is in factno evidence for me that anyone else but me has a mind. I disagree with hisacceptance of it! It would be better to give up the neo-Cartesian faith in private conscious experience underlying Harnad's allegiance to Searle's controversial Chinese Room Experiment than give up all claim to know others think. It would be better to allow that (passing) Turing's Test evidences — evenstrongly evidences — thought.  相似文献   

11.
Concept learning in robotics is an extremely challenging problem: sensory data is often high-dimensional, and noisy due to specularities and other irregularities. In this paper, we investigate two general strategies to speed up learning, based on spatial decomposition of the sensory representation, and simultaneous learning of multiple classes using a shared structure. We study two concept learning scenarios: a hallway navigation problem, where the robot has to induce features such as opening or wall. The second task is recycling, where the robot has to learn to recognize objects, such as a trash can. We use a common underlying function approximator in both studies in the form of a feedforward neural network, with several hundred input units and multiple output units. Despite the high degree of freedom afforded by such an approximator, we show the two strategies provide sufficient bias to achieve rapid learning. We provide detailed experimental studies on an actual mobile robot called PAVLOV to illustrate the effectiveness of this approach.  相似文献   

12.
Lionel Snell 《AI & Society》1989,3(3):247-255
This article looks at the broadest implications of public acceptance of AI. A distinction is drawn between conscious belief in a technology, and organic belief where the technology is incorporated into an unconscious world model. The extent to which we feel threatened by AI's apparent denial of spirit is considered, along with a discussion of how people react to this threat. It is proposed that organic acceptance of AI models would lead to a rebirth of popular spiritual concepts as paradoxical as the New Age ideas that have their roots in the theories of physics. Finally the relevance of this speculation is discussed in terms of how it could impinge upon public acceptability of AI technology.  相似文献   

13.
Linear logic, introduced by J.-Y. Girard, is a refinement of classical logic providing means for controlling the allocation of resources. It has aroused considerable interest from both proof theorists and computer scientists. In this paper we investigate methods for automated theorem proving in propositional linear logic. Both the bottom-up (tableaux) and top-down (resolution) proof strategies are analyzed. Various modifications of sequent rules and efficient search strategies are presented along with the experiments performed with the implemented theorem provers.  相似文献   

14.
The Diplomat rapid-deployment speech-translation systemis intended to allow naï ve users to communicate across a languagebarrier, without strong domain restrictions, despite the error-pronenature of current speech and translation technologies. In addition,it should be deployable for new languages an order of magnitude morequickly than traditional technologies. Achieving this ambitious setof goals depends in large part on allowing the users to correct recognition and translation errors interactively. We present the Multi-Engine Machine Translation (MEMT) architecture, describing how it is well suited for such an application. We then discuss ourapproaches to rapid-deployment speech recognition and synthesis.Finally we describe our incorporation of interactive error correctionthroughout the system design. We have already developed workingbidirectional Croatian English and Spanish English systems, and have Haitian Creole English and Korean English versions under development.  相似文献   

15.
Data structures are interpreted as sets which may contain repeating elements. An algebraic system close to the integer ring is constructed on these sets.Translated from Kibernetika, No. 4, pp. 82–88, July–August, 1990.  相似文献   

16.
Modeling and programming tools for neighborhood search often support invariants, i.e., data structures specified declaratively and automatically maintained incrementally under changes. This paper considers invariants for longest paths in directed acyclic graphs, a fundamental abstraction for many applications. It presents bounded incremental algorithms for arc insertion and deletion which run in O( + || log||) time and O() time respectively, where || and are measures of the change in the input and output. The paper also shows how to generalize the algorithm to various classes of multiple insertions/deletions encountered in scheduling applications. Preliminary experimental results show that the algorithms behave well in practice.  相似文献   

17.
In 1996, the author attended a seminar on ethics given by C. West Churchman at the University of California, Berkeley. During that year, the author also interviewed Churchman several times regarding the future direction of information sciences in general and the information systems research field in particular. This article is a compilation of the seminar and the interviews. It is set in the context of both Churchman's earlier and his current views of a global god, good, kindness, and caring. C. West Churchman holds that global ethics should lead to the study and design of information systems to solve large and difficult problems of the humankind such as poverty, crime and disease. His Global Ethical Management (GEM) of information sciences translates into abandoning the current goals and boundaries of the information sciences fields and changing what constitutes valid research to globally ethical endeavors.  相似文献   

18.
Mutual convertibility of bound entangled states under local quantum operations and classical communication (LOCC) is studied. We focus on states associated with unextendible product bases (UPB) in a system of three qubits. A complete classification of such UPBs is suggested. We prove that for any pair of UPBs S and T the associated bound entangled states S and T cannot be converted to each other by LOCC, unless S and T coincide up to local unitaries. More specifically, there exists a finite precision (S,T) > 0 such that for any LOCC protocol mapping S into a probabilistic ensemble (p, ), the fidelity between T and any possible final state satisfies F(T, ) = 1 - (S,T).PACS: 03.65.Bz; 03.67.-a; 89.70+c.  相似文献   

19.
The paper introduces the concept of Computer-based Informated Environments (CBIEs) to indicate an emergent form of work organisation facilitated by information technology. It first addresses the problem of inconsistent meanings of the informate concept in the literature, and it then focuses on those cases which, it is believed, show conditions of plausible informated environments. Finally, the paper looks at those factors that when found together contribute to building a CBIE. It makes reference to CBIEs as workplaces that comprise a non-technocentric perspective and questions whether CBIEs truly represent an anthropocentric route of information technology.  相似文献   

20.
Dr. T. Ström 《Computing》1972,10(1-2):1-7
It is a commonly occurring problem to find good norms · or logarithmic norms (·) for a given matrix in the sense that they should be close to respectively the spectral radius (A) and the spectral abscissa (A). Examples may be the certification thatA is convergent, i.e. (A)A<1 or stable, i.e. (A)(A)<0. Often the ordinary norms do not suffice and one would like to try simple modifications of them such as using an ordinary norm for a diagonally transformed matrix. This paper treats this problem for some of the ordinary norms.
Minimisierung von Normen und Logarithmischen Normen durch Diagonale Transformationen
Zusammenfassung Ein oft vorkommendes praktisches Problem ist die Konstruktion von guten Normen · und logarithmischen Normen (·) für eine gegebene MatrixA. Mit gut wird dann verstanden, daß A den Spektralradius (A)=max |1| und (A) die Spektralabszisse (A)=max Re i gut approximieren. Beispiele findet man für konvergente Matrizen wo (A)A<1 gewünscht ist, und für stabile Matrizen wo (A)(A)<0 zu zeigen ist. Wir untersuchen hier, wie weit man mit Diagonaltransformationen und dengewöhnlichsten Normen kommen kann.
  相似文献   

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