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1.
By looking at a person’s hands, one can often tell what the person is going to do next, how his/her hands are moving and where they will be, because an actor’s intentions shape his/her movement kinematics during action execution. Similarly, active systems with real-time constraints must not simply rely on passive video-segment classification, but they have to continuously update their estimates and predict future actions. In this paper, we study the prediction of dexterous actions. We recorded videos of subjects performing different manipulation actions on the same object, such as “squeezing”, “flipping”, “washing”, “wiping” and “scratching” with a sponge. In psychophysical experiments, we evaluated human observers’ skills in predicting actions from video sequences of different length, depicting the hand movement in the preparation and execution of actions before and after contact with the object. We then developed a recurrent neural network based method for action prediction using as input image patches around the hand. We also used the same formalism to predict the forces on the finger tips using for training synchronized video and force data streams. Evaluations on two new datasets show that our system closely matches human performance in the recognition task, and demonstrate the ability of our algorithms to predict in real time what and how a dexterous action is performed.  相似文献   

2.
Having a sequence diagram specification and a computer system, we need to answer the question: Is the system compliant with the sequence diagram specification in the desired way? We present a procedure for answering this question for sequence diagrams with underspecification and inherent nondeterminism. The procedure is independent of any concrete technology, and relies only on the execution traces that may be produced by the system. If all traces are known, the procedure results in either “compliant” or “not compliant”. If only a subset of the traces is known, the conclusion may also be “likely compliant” or “likely not compliant”.  相似文献   

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4.
Test selection in diagnosis is a procedure suggesting tests to be executed when trying to answer the query “What is the diagnosis for this problem?”. However, other queries, such as “Is h the diagnosis for this problem?”, are relevant as they can involve faster test selection algorithms and they can result in a lower test execution cost. Usually, a one step lookahead entropy minimization strategy is adopted to implement the test selection procedure. However, we show that this strategy can be arbitrarily bad and therefore, it is important to consider several strategies to solve a query. Each strategy taking a different position in the tradeoff computation time vs test execution cost. In this paper, we consider a query-based approach where test selection is justified and driven by a user’s specific query. We also study different strategies, optimal and approximate, for test selection. Finally, we illustrate how the operating system discovery (OSD) problem can be solved using a diagnosis framework and how it benefits from a query-based approach.  相似文献   

5.
Each one of the popular discrete event simulation languages GPSS and GASP IV has a large user community. GPSS is probably the most widely used discrete event simulation language; it is appreciated for its ease of use and for the structural similarity of a GPSS model to the system it represents. GASP IV has provided (along with its successor, SLAM) a viable, well-documented system for combined continuous/discrete modeling and simulation. This paper presents the design and prototype development of a simulation language system called GGC, based upon a combination of GPSS and GASP IV. The new language system seeks to provide the “best of both worlds” in supporting the use of a GASP-based continuous mode in conjunction with GPSS use for discrete event modeling. An example of GGC use in a combined continuous/discrete model is presented. Possible future approaches are suggested based on conclusions drawn.  相似文献   

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We contrast person-centered categories with “objective” categories related to physics: consciousness vs. mechanism, observer vs. observed, agency vs. event causation. semantics vs. syntax, beliefs and desires vs. dispositions. How are these two sets of categories related? This talk will discuss just one such dichotomy: consciousness vs. mechanism. Two extreme views are dualism and reductionism. An intermediate view is emergence. Here, consciousness is part of the natural order (as against dualism), but consciousness is not definable only in terms of physical mass, length, and time (as against reductionism). There are several detailed theories of emergence. One is based on the Great Chain of Being and on organic evolutionary hierarchy. The theory here is based instead on the concept of “relational holism” in quantum mechanics. The resulting brain model has two interacting systems: a computational system and a quantum system (a Bose-Einstein condensate), perhaps interacting via EEG waves. Thus, we need both person-centered and matter-centered categories to describe human beings. Some possible experimental tests are discussed.  相似文献   

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9.
邹强 《图学学报》2022,43(6):987-1001
实体建模技术是CAD软件的“功能心脏”,相关基础理论与算法是CAD发展历史上最关键的成果之一,成功回答了为使计算机能够辅助产品设计与制造,需在计算机中存什么几何信息以及怎么存的问题。本文对实体建模的主要历史发展脉络做了简要介绍,同时对各发展阶段的关键问题以及研究现状进行了讨论,最后选取了3个方向对实体建模的未来做出展望,重点关注从Computer-Aided Design到Computer-Automated Design的发展趋势。  相似文献   

10.
We examine carefully the rationale underlying the approaches to belief change taken in the literature, and highlight what we view as methodological problems. We argue that to study belief change carefully, we must be quite explicit about the “ontology” or scenario underlying the belief change process. This is something that has been missing in previous work, with its focus on postulates. Our analysis shows that we must pay particular attention to two issues that have often been taken for granted: the first is how we model the agent's epistemic state. (Do we use a set of beliefs, or a richer structure, such as an ordering on worlds? And if we use a set of beliefs, in what language are these beliefs are expressed?) We show that even postulates that have been called “beyond controversy” are unreasonable when the agent's beliefs include beliefs about her own epistemic state as well as the external world. The second is the status of observations. (Are observations known to be true, or just believed? In the latter case, how firm is the belief?) Issues regarding the status of observations arise particularly when we consider iterated belief revision, and we must confront the possibility of revising by φ and then by ¬ φ.  相似文献   

11.
A computerized modeling system is described which presents the analysis of a large number of interacting units operating at various levels of managerial control. The COMO-III system employs a “tool kit” approach to modelling by providing great flexibility in fitting the various parts of the model together. The decision maker/manager can directly interact with the model through a special COMIL language to permit “what if” analysis to be performed in direct support of the decision process.First the model is described in general and then we report the application of the COMO-III modeling system to a theater level air defense simulation. COMO-III is an advanced simulation package developed by the SHAPE Technical Center (The Hague, Netherlands). We believe that this may be the first such simulation of theater level combat in the level of detail described. A large number of individual air defense weapons are simulated on an event oriented basis. The COMO-III system demonstrated to us a considerable state-of-the-art advancement in the methodology of military simulation. Our development efforts also encompassed an expansion of COMO-III to include interactive gaming of individual Air Force interceptor aircraft which showed the model to be unusually flexible. Representative simulation results are presented together with perceived advantages from employing the COMO-III system. It has both methodological and managerial advantages and is entirely government owned and operated. Because the features of COMO-III have not been previously described in the literature, a specially constructed example and commentary are included in an appendix. Implications for future applications are also introduced.  相似文献   

12.
Kurt Gödel’s Incompleteness theorem is well known in Mathematics/Logic/Philosophy circles. Gödel was able to find a way for any given P (UTM), (read as, “P of UTMforProgram of Universal Truth Machine”), actually to write down a complicated polynomial that has a solution iff (=if and only if), G is true, where G stands for a Gödel-sentence. So, if G’s truth is a necessary condition for the truth of a given polynomial, then P (UTM) has to answer first that G is true in order to secure the truth of the said polynomial. But, interestingly, P (UTM) could never answer that G was true. This necessarily implies that there is at least one truth a P (UTM), however large it may be, cannot speak out. Daya Krishna and Karl Potter’s controversy regarding the construal of India’s Philosophies dates back to the time of Potter’s publication of “Presuppositions of India’s Philosophies” (1963, Englewood Cliffs Prentice-Hall Inc.) In attacking many of India’s philosophies, Daya Krishna appears to have unwittingly touched a crucial point: how can there be the knowledge of a ‘non-cognitive’ mok?a? [‘mok?a’ is the final state of existence of an individual away from Social Contract]—See this author’s Indian Social Contract and its Dissolution (2008) mok?a does not permit the knowledge of one’s own self in the ordinary way with threefold distinction, i.e., subject–knowledge-object or knower–knowledge–known. But what is important is to demonstrate whether such ‘knowledge’ of non-cognitive mok?a state can be logically shown, in a language, to be possible to attain, and that there is no contradiction involved in such demonstration, because, no one can possibly express the ‘experience-itself’ in language. Hence, if such ‘knowledge’ can be shown to be logically not impossible in language, then, not only Daya Krishna’s arguments against ‘non-cognitive mok?a’ get refuted but also it would show the possibility of achieving ‘completeness’ in its truest sense, as opposed to Gödel’s ‘Incompleteness’. In such circumstances, man would himself become a Universal Truth Machine. This is because the final state of mok?a is construed as the state of complete knowledge in Advaita. This possibility of ‘completeness’ is set in this paper in the backdrop of ?rī ?a?karācārya’s Advaitic (Non-dualistic) claim involved in the mahāvākyas (extra-ordinary propositions). (Mahāvākyas that ?a?kara refers to are basically taken from different Upani?ads. For example, “Aham Brahmāsmi” is from B?hadāra?yaka Upanisad, and “Tattvamasi” is from Chāndogya Upani?ad. ?rī ?a?karācārya has written extensively. His main works include his Commentary on Brahma-Sūtras, on major Upani?ads, and on ?rīmadBhagavadGītā, called Bhā?yas of them, respectively. Almost all these works are available in English translation published by Advaita Ashrama, 5 Dehi Entally Road, Calcutta, 700014.) On the other hand, the ‘Incompleteness’ of Gödel is due to the intervening G-sentence, which has an adverse self-referential element. Gödel’s incompleteness theorem in its mathematical form with an elaborate introduction by R.W. Braithwaite can be found in Meltzer (Kurt Gödel: on formally undecidable propositions of principia mathematica and related systems. Oliver &; Boyd, Edinburgh, 1962). The present author believes first that semantic content cannot be substituted by any amount of arithmoquining, (Arithmoquining or arithmatization means, as Braithwaite says,—“Gödel’s novel metamathematical method is that of attaching numbers to the signs, to the series of signs (formulae) and to the series of series of signs (“proof-schemata”) which occur in his formal system…Gödel invented what might be called co-ordinate metamathematics…”) Meltzer (1962 p. 7). In Antone (2006) it is said “The problem is that he (Gödel) tries to replace an abstract version of the number (which can exist) with the concept of a real number version of that abstract notion. We can state the abstraction of what the number needs to be, [the arithmoquining of a number cannot be a proof-pair and an arithmoquine] but that is a concept that cannot be turned into a specific number, because by definition no such number can exist.”.), especially so where first-hand personal experience is called for. Therefore, what ultimately rules is the semanticity as in a first-hand experience. Similar points are voiced, albeit implicitly, in Antone (Who understands Gödel’s incompleteness theorem, 2006). (“…it is so important to understand that Gödel’s theorem only is true with respect to formal systems—which is the exact opposite of the analogous UTM (Antone (2006) webpage 2. And galatomic says in the same discussion chain that “saying” that it ((is)) only true for formal systems is more significant… We only know the world through “formal” categories of understanding… If the world as it is in itself has no incompleteness problem, which I am sure is true, it does not mean much, because that is not the world of time and space that we experience. So it is more significant that formal systems are incomplete than the inexperiencable ‘World in Itself’ has no such problem.—galatomic”) Antone (2006) webpage 2. Nevertheless galatomic certainly, but unwittingly succeeds in highlighting the possibility of experiencing the ‘completeness’ Second, even if any formal system including the system of Advaita of ?a?kara is to be subsumed or interpreted under Gödel’s theorem, or Tarski’s semantic unprovability theses, the ultimate appeal would lie to the point of human involvement in realizing completeness since any formal system is ‘Incomplete’ always by its very nature as ‘objectual’, and fails to comprehend the ‘subject’ within its fold.  相似文献   

13.
Problems with portability of applications across various Linux distributions is one of the major sore spots of independent software vendors (ISVs) wishing to support the Linux platform in their products. The source of the problem is that different distributions have different sets of system libraries that vary in the interfaces (APIs) provided. And the critical questions arise for ISVs such as “which distributions my application would run on?” or “what can I specifically do to make my application run on a greater number of distributions?”. This article refers to an industry-wide approach to mitigate the problem of Linux platform fragmentation through standardization of common interfaces—the Linux Standard Base (LSB) standard, the leading effort for the “single Linux specification”. The article shows how extending this approach with a knowledge base about the composition of real world Linux distributions can enable automatic portability analysis for Linux applications even if they use interfaces outside the scope of the standard. The knowledge base powered Linux Application Checker tool is described that can help answer the above questions by automatically analyzing the target application and confronting collected data about its external dependencies with what various distributions provide. Additionally, Linux Application Checker is an official tool approved by the Linux Foundation for certifying applications for compliance with the LSB standard.  相似文献   

14.
If a brain is duplicated so that there are two brains in identical states, are there then two numerically distinct phenomenal experiences or only one? There are two, I argue, and given computationalism, this has implications for what it is to implement a computation. I then consider what happens when a computation is implemented in a system that either uses unreliable components or possesses varying degrees of parallelism. I show that in some of these cases there can be, in a deep and intriguing sense, a fractional (non-integer) number of qualitatively identical phenomenal experiences. This, in turn, has implications for what lessons one should draw from neural replacement scenarios such as Chalmers’ “Fading Qualia” thought experiment.  相似文献   

15.
Aspect-oriented modeling (AOM) is a relatively recent and very active field of research, whose application has, however, been limited in practice. AOM is assumed to yield several potential benefits such as enhanced modularization, easier evolution, increased reusability, and improved readability of models, as well as reduced modeling effort. However, credible, solid empirical evidence of such benefits is lacking. We evaluate the “readability” of state machines when modeling crosscutting behavior using AOM and more specifically AspectSM, a recently published UML profile. This profile extends the UML state machine notation with mechanisms to define aspects using state machines. Readability is indirectly measured through defect identification and fixing rates in state machines, and the scores obtained when answering a comprehension questionnaire about the system behavior. With AspectSM, crosscutting behavior is modeled using so-called “aspect state machines”. Their readability is compared with that of system state machines directly modeling crosscutting and standard behavior together. An initial controlled experiment and a much larger replication were conducted with trained graduate students, in two different institutions and countries, to achieve the above objective. We use two baselines of comparisons—standard UML state machines without hierarchical features (flat state machines) and standard state machines with hierarchical/concurrent features (hierarchical state machines). The results showed that defect identification and fixing rates are significantly better with AspectSM than with both flat and hierarchical state machines. However, in terms of comprehension scores and inspection effort, no significant difference was observed between any of the approaches. Results of the experiments suggest that one should use, when possible, aspect state machines along with hierarchical and/or concurrent features of UML state machines to model crosscutting behaviors.  相似文献   

16.
《Artificial Intelligence》2006,170(14-15):1081-1100
We present a trainable sequential-inference technique for processes with large state and observation spaces and relational structure. We apply our technique to the problem of force-dynamic state inference from video, which is a critical component of the LEONARD [J.M. Siskind, Grounding lexical semantics of verbs in visual perception using force dynamics and event logic, Journal of Artificial Intelligence Research 15 (2001) 31–90] visual-event recognition system. LEONARD uses event definitions that are grounded in force-dynamic primitives—making robust and efficient force-dynamic inference critical to good performance. Our sequential-inference method assumes “reliable observations”, i.e., that each process state (e.g., force-dynamic state) persists long enough to be reliably inferred from the observations (e.g., video frames) it generates. We introduce the idea of a “state-inference function” (from observation sequences to underlying hidden states) for representing knowledge about a process and develop an efficient sequential-inference algorithm, utilizing this function, that is correct for processes that generate reliable observations consistent with the state-inference function. We describe a representation for state-inference functions in relational domains and give a corresponding supervised learning algorithm. Our experiments in force-dynamic state inference show that our technique provides significantly improved accuracy and speed relative to a variety of recent, hand-coded, non-trainable systems, and a trainable system based on probabilistic modeling.  相似文献   

17.
We investigate the space of singular curves associated to a distribution ofk-planes, or, what is the same thing, a nonlinear deterministic control system linear in controls. A singular curve is one for which the associated linearized system is not controllable. If a quadratic positive-definite cost function is introduced, then the corresponding optimal control problem is known as the sub-Riemannian geodesic problem. The original motivation for our work was the question “Are all sub-Riemannian minimizers smooth?” which is equivalent to the question “Are singular minimizers necessarily smooth?” Our main result concerns the singular curves for a class of homogeneous systems whose state spaces are compact Lie groups. We prove that for this class each singular curve lies in a lower-dimensional subgroup within which it is regular and we use this result to prove that all sub-Riemannian minimizers are smooth. A central ingredient of our proof is a symplectic-geometric characterization of singular curves formulated by Hsu. We extend this characterization to nonsmooth singular curves. We find that the symplectic point of view clarifies the situation and simplifies calculations.  相似文献   

18.
This paper studies the real‐life problem of dynamically optimizing the number of airport check‐in counters to allocate for a single flight. The main feature of our work is the use of empirical data collected at the Singapore Changi Airport, which drives the dynamic optimization model of a parallel queues system. We propose an event‐based dynamic programming model that simplifies considerably the optimization analysis even for large‐scale problems with 700+ booked passengers. We investigate the following research questions: (a) For a particular flight, what is the optimal number of counters the system should open with and what is the corresponding optimal total cost? (b) Given the state of the system at any event epoch, should we open another counter or not and what is the optimal cost‐to‐go from this state? The empirical data we collected at the airport are used to test the assumptions, estimate the key parameters, and run the computational experiments. We apply our model to 14 flights at the Singapore Changi Airport and identify cases in which, depending on the cost parameters, the model advocates the use of either a dynamic or a static policy. Although the model concerns only an exclusive‐use system, it is flexible enough to apply to other configurations such as a common‐use system or a single‐queue, multicounter system.  相似文献   

19.
Prior empirical studies of programming have shown that novice programmers tend to program by exploration, relying on frequent compilation and execution of their code in order to make progress. One way visual and end-user programming environments have attempted to facilitate this exploratory programming process is through their support of “live” editing models, in which immediate visual feedback on a program's execution is provided automatically at edit time. Notice that the notion of “liveness” actually encompasses two distinct dimensions: (a) the amount of time a programmer must wait between editing a program and receiving visual feedback (feedback delay); and (b) whether such feedback is provided automatically, or whether the programmer must explicitly request it (feedback self-selection). While a few prior empirical studies of “live” editing do exist, none has specifically evaluated the impact of these dimensions of “live” editing within the context of the imperative programming paradigm commonly taught in first-semester computer science courses. As a preliminary step toward that end, we conducted an experimental study that investigated the impact of feedback self-selection on novice imperative programming. Our within-subjects design compared the impact of three different levels of feedback self-selection on syntactic and semantic correctness: (a) no visual feedback at all (the No Feedback treatment); (b) visual feedback, in the form of a visualization of the program's execution state, provided on request when a “run” button is hit (the Self-Select treatment); and (c) visual feedback, in the form of a visualization of the program's execution state, updated on every keystroke (the Automatic treatment). Participants in the Automatic and Self-Select treatments produced programs that had significantly fewer syntactic and semantic errors than those of the No Feedback treatment; however, no significant differences were found between the Automatic and Self-Select treatments. These results suggest that, at least in the case of novice imperative programming environments, the benefits of delivering a continuously updated visual representation of a program's execution may fail to justify the substantial costs of implementing such feedback. We recommend that programming environment designers instead direct their efforts toward carefully considering when programmers will be ready to take advantage of the feedback that is coming toward them, along with what content will be of most benefit to them.  相似文献   

20.
Context-aware and pervasive computing applications have increased their number during the last decade, thanks to the development of new communication and mobile technologies. These applications cover a wide spectrum of problems, sectors, scenarios, and environments that aim to build smart environments supporting many kinds of human interactions. Tourism is an important economic sector for many cities and countries and therefore a research area where the development of ubiquitous applications is having a great interest. In this paper, we propose a solution oriented to help the user to find the location of interest points within the city and navigate through them. In this work, we propose the use of mobile phones with the near-field communication technology incorporated and Smart Posters disseminated along the city. Indoor and outdoor locations and navigation are allowed, “where is it?”, “what is it?”, “where am I?”, “what is there around me?” and the remaining hits of locations and navigation paradigms are supported by an easy, cheap, and context-awareness system without the need of hard tasks to the user related to system installation or tailoring.  相似文献   

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