Many real natural or man-made dynamic systems can be better characterized using a fractional order dynamic model. Since in such a case the order assumes a non-integer value, it is of interest to consider the effect of...
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Many real natural or man-made dynamic systems can be better characterized using a fractional order dynamic model. Since in such a case the order assumes a non-integer value, it is of interest to consider the effect of small perturbation around the nominal value. It is of practical importance to analyze the influence of the order variations on the system behavior. This paper establishes an analytical method for the analysis of the sensitivity function of LTI fractional order dynamic systems with respect to the orders. The continuous dependent condition of the orders of fractional Green's function is derived, which is proved as a necessary and sufficient condition. The singularity of fractional Green's functions is discussed. Several examples are included for illustration.
Real time rendering of three-dimensional scenes in high photorealistic detail is a hard task, such as in the Ray Tracing rendering algorithm. However, parallel implementations of Ray Tracing have been enabling real ti...
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Real time rendering of three-dimensional scenes in high photorealistic detail is a hard task, such as in the Ray Tracing rendering algorithm. However, parallel implementations of Ray Tracing have been enabling real time performance, as the algorithm is embarrassingly parallel. Thus, a custom parallel design in hardware is likely to achieve an acceptable performance. In this paper, we propose a hardware parallel architecture capable of dealing with the main desirable features of Ray Tracing, such as shadows and reflection effects, imposing low area cost and acceptable rendering performance.
This paper firstly addresses the convergence analysis of iterative learning control of a class of fractional order nonlinear systems using the generalized Gronwall-Bellman lemma. Detailed problem definition and conver...
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This paper firstly addresses the convergence analysis of iterative learning control of a class of fractional order nonlinear systems using the generalized Gronwall-Bellman lemma. Detailed problem definition and convergence proof are presented together with an agenda for future research efforts.
In this paper, a control mechanism is presented to improve the compliance performance of the robot manipulator when it is in contact with the unknown environment. This mechanism guarantees that the dynamics of the who...
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Most existing performance evaluation methods concentrate on defining separate metrics over a wide range of conditions and generating standard benchmarking video sequences for examining the effectiveness of video track...
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Most existing performance evaluation methods concentrate on defining separate metrics over a wide range of conditions and generating standard benchmarking video sequences for examining the effectiveness of video tracking systems. In other words, these methods attempt to design a robustness margin or factor for the system. These methods are deterministic in which a robustness factor, for example, 2 or 3 times the expected number of subjects to track or the strength of illumination would be required in the design. This often results in over design, thus increasing costs, or under design causing failure by unanticipated factors. In order to overcome these limitations, we propose in this paper an alternative framework to analyze the physics of the failure process and, through the concept of reliability, determine the time to failure in automated video tracking systems. The benefit of our proposed framework is that we can provide a unified and statistical index to evaluate the performance of automated video tracking system for a task to be performed. At the same time, the uncertainty problem about a failure process, which may be caused by the system's complexity, imprecise measurements of the relevant physical constants and variables, or the indeterminate nature of future events, can be addressed accordingly based on our proposed framework.
The zero-error classical capacity of a quantum channel is the asymptotic rate at which it can be used to send classical bits perfectly, so that they can be decoded with zero probability of error. The study of zero-err...
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ISBN:
(纸本)9781424478903
The zero-error classical capacity of a quantum channel is the asymptotic rate at which it can be used to send classical bits perfectly, so that they can be decoded with zero probability of error. The study of zero-error capacities dates right back to Shannon and the early days of information theory. We show that there exist pairs of quantum channels, neither of which individually have any zero-error capacity whatsoever (even if arbitrarily many uses of the channels are available), but such that access to even a single copy of both channels allows classical information to be sent perfectly reliably. In other words, we prove that the zero-error classical capacity can be superactivated. This result is the first example of superactivation of a classical capacity of a quantum channel. We further strengthen this result to show that there exist pairs of channels, neither of which have any zero-error classical capacity (as before), yet for which access to one copy of the joint channel even allows far more delicate quantum information to be transmitted perfectly. This subsumes the first result, and also implies that the quantum zero-error capacity can be superactivated. But it is strictly stronger than either of these. Indeed, this is the strongest conceivable form of superactivation, and nothing similar is possible for standard Shannon capacities of quantum channels or for zero-error capacities of classical channels.
Specific images refer to images one has a certain episodic memory about, e.g. a picture one has ever seen before. Specific image retrieval is a frequent daily information need and the episodic memory is the key to fin...
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Specific images refer to images one has a certain episodic memory about, e.g. a picture one has ever seen before. Specific image retrieval is a frequent daily information need and the episodic memory is the key to find a specific image. In this paper, we propose a novel semantic sketch-based interface to incorporate the episodic memory for specific image retrieval. The interface allows a user to specify the semantic category and rough area/color of the objects in his memory. To bridge the semantic gap between the query sketch and database images, in the back end, a sampling method selects exemplars from a reference dataset which contains many object instances with user-provided tags and bounding boxes. After that, an exemplar matching algorithm ranks images to retrieve the target image to match the user's memory. In practice, we have observed that query sketches are usually error prone. That is, the position or the color of an object may not be accurate. Meanwhile, the annotations in the reference dataset are also noisy. Thus, the search algorithm has to handle two kinds of errors: 1) reference dataset label noise; 2) user sketch error such as position or scale. For the former, we propose a robust sampling method. For the latter, we derive an efficient spatial reranking algorithm to tolerate inaccurate user sketches. Detailed experimental results on the LabelMe dataset show that the proposed approach is robust to both kinds of errors.
Sexual selection has been mathematically modeled using quantitative genetics as well as population genetics. Two-locus simulation models have been used to study the evolution of male display and female preference. We ...
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Sexual selection has been mathematically modeled using quantitative genetics as well as population genetics. Two-locus simulation models have been used to study the evolution of male display and female preference. We present an individual-based simulation model of sexual selection in a quantitative genetic context. We show that under certain conditions Fisherian self-reinforcing sexual selection takes effect, predicted by Lande’s analytic model of female choice. We also show that the dynamics involved in the co-evolution of male display and female preference is much more complex than mathematics would predict. We therefore argue that the study of sexual selection through individual-based simulation could give new and more realistic insight into a world dominated by overly simplified equations.
Based on adaptive and ℋ ∞ control techniques, this paper deals with the problem of active fault-tolerant control for a class of T-S fuzzy systems with actuator faults. The presented approach is dependent on a fuzzy ...
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Based on adaptive and ℋ ∞ control techniques, this paper deals with the problem of active fault-tolerant control for a class of T-S fuzzy systems with actuator faults. The presented approach is dependent on a fuzzy iterative learning observer (ILO), which produces a control input adjustment term in order to compensate for the effect of actuator faults. Based on Lyapunov theorem, a sufficient condition for the stability of error dynamic systems is derived. The active fault-tolerant control strategy proposed in the paper is finally demonstrated in simulation on the near space vehicle (NSV) reentry attitude dynamics to illustrate its effectiveness.
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