We describe a variant of TCP, called FAST, that can sustain high throughput and utilization at multigigabits per second over large distances. We present the motivation, review the background theory, summarize key feat...
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We describe a variant of TCP, called FAST, that can sustain high throughput and utilization at multigigabits per second over large distances. We present the motivation, review the background theory, summarize key features of FAST TCP, and report our first experimental results.
As global online access to information becomes more common, the technology ofmultilingual optical character recognition (OCR) increases in importance as a way to convert paperdocuments into electronic, searchable, tex...
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As global online access to information becomes more common, the technology ofmultilingual optical character recognition (OCR) increases in importance as a way to convert paperdocuments into electronic, searchable, text. In OCR, as in any evolving technology, carefulevaluation is an integral part of research and development. OCR evaluation is done by comparing asystem's output for a dataset of document test images with the corresponding correct symbolic text,known as ground truth. Unfortunately, the usual way of obtaining ground truth is by manual dataentry by humans, which is labor-intensive, time-consuming, expensive, and prone to errors. Worse,because no single set of ground truth evaluation data can be used in more than one language, therehas until now been no way to conduct carefully controlled OCR experiments in a multilingual setting.
We describe a novel method for using genetic programming to create compact classification rules using combinations of N-grams ( character strings). Genetic programs acquire fitness by producing rules that are effectiv...
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We describe a novel method for using genetic programming to create compact classification rules using combinations of N-grams ( character strings). Genetic programs acquire fitness by producing rules that are effective classifiers in terms of precision and recall when evaluated against a set of training documents. We describe a set of functions and terminals and provide results from a classification task using the Reuters 21578 dataset. We also suggest that the rules may have a number of other uses beyond classification and provide a basis for text mining applications.
For the discrete systems with random parameters perturbed by additive and multiplicative noise depending on the states and controls, design of the predictive model-based control strategies was considered. Predictive c...
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For the discrete systems with random parameters perturbed by additive and multiplicative noise depending on the states and controls, design of the predictive model-based control strategies was considered. Predictive control strategies of closed-loop and open-loop types were developed. The results obtained were applied to dynamic optimization of the investment portfolio under constrained volumes of trade operations.
There are two major approaches for converting a tessellated CAD model that contains inconsistencies like cracks or intersections into a manifold and closed triangle mesh. Surface oriented algorithms try to fix the inc...
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There are two major approaches for converting a tessellated CAD model that contains inconsistencies like cracks or intersections into a manifold and closed triangle mesh. Surface oriented algorithms try to fix the inconsistencies by perturbing the input only slightly, but the), often cannot handle special cases. Volumetric algorithms on the other hand produce guaranteed manifold meshes but mostly destroy the structure of the input tessellation due to global resampling. In this paper we combine the advantages of both approaches: We exploit the topological simplicity of a voxel grid to reconstruct a cleaned up surface in the vicinity of intersections and cracks, but keep the input tessellation in regions that are away from these inconsistencies. We are thus able to preserve any characteristic structure (i.e. iso-parameter or curvature lines) that might be present in the input tessellation. Our algorithm closes gaps up to a user-defined maximum diameter resolves intersections, handles incompatible patch orientations and produces a feature-sensitive, manifold output that stays within a prescribed error-tolerance to the input model.
A problem of robust control of routing for preventing the congestion in digital information networks is considered. Models for both duplex and semiduplex data communication channels (data channels) are suggested. For ...
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A problem of robust control of routing for preventing the congestion in digital information networks is considered. Models for both duplex and semiduplex data communication channels (data channels) are suggested. For the problem of robust control of routing, the factorization operation of the traffic matrix of an information network is proposed, which plays an important role in the development of a control algorithm. Robust control algorithms are proposed, in which use is made of alternate paths with an arbitrary number of links. Properties of the suggested algorithm are studied. Model examples of information networks are given, which display the effectiveness of the suggested algorithms of robust routing.
In this paper we present an image-based algorithm for surface reconstruction of moving garment from multiple calibrated video cameras. Using a color-coded cloth texture, we reliably match circular features between dif...
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In this paper we present an image-based algorithm for surface reconstruction of moving garment from multiple calibrated video cameras. Using a color-coded cloth texture, we reliably match circular features between different camera views. As surface model we use air a priori known triangle mesh. By identifying the mesh vertices with texture elements we obtain a consistent parameterization of the surface over time without further processing. Missing data points resulting from self-shadowing are plausibly interpolated by minimizing a thin-plate functional. The deforming geometry can be used for different graphics applications, e.g. for realistic retexturing. We show results for real garments demonstrating the accuracy of the recovered flexible shape.
This paper presents a robust nonlinear control that uses a variable estimator for control of a single degree of freedom manipulator actuated by shape memory alloy (SMA) wire. A model for SMA actuated manipulator is pr...
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This paper presents a robust nonlinear control that uses a variable estimator for control of a single degree of freedom manipulator actuated by shape memory alloy (SMA) wire. A model for SMA actuated manipulator is presented The model includes nonlinear dynamics of the manipulator a constitutive model of the shape memory alloy, and the electrical and transfer behavior of SMA wire. The current experimental setup allows for the measurement of only one state variable which is the angular position of the arm. Due to measurement difficulties, the other three state variables, arm angular velocity and SMA wire stress and temperature, cannot be directly measured. A model-based state estimator that works with noisy measurements is presented based on the extended Kalman filter (EKF). This estimator estimates the state vector at each time step and corrects its estimation based on the angular position measurements. The estimator is then used in a nonlinear and robust control algorithm based on variable structure control (VSC). The VSC algorithm is a control gain switching technique based on the arm angular position (and velocity) feedback and EKF estimated SMA wire stress and temperature. Using simulation it is shown that the state vector estimates help reduce or avoid the undesirable and inefficient overshoot problem in SMA one-way actuation control.
A new stochastic approximation algorithm with input perturbation for self-learning is designed with test perturbations and has certain useful properties, such as consistency of estimates tinder almost arbitrary pertur...
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A new stochastic approximation algorithm with input perturbation for self-learning is designed with test perturbations and has certain useful properties, such as consistency of estimates tinder almost arbitrary perturbations and preservation of simplicity and performance with the growing size of the state space and increasing number of classes. An example. oil computer-aided modeling of learning is given to illustrate the performance of the algorithm.
We formulate a new approach for evaluating a prefetching algorithm. We first carry out a profiling run of a program to identify all of the misses and corresponding locations in the program where prefetches for the mis...
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We formulate a new approach for evaluating a prefetching algorithm. We first carry out a profiling run of a program to identify all of the misses and corresponding locations in the program where prefetches for the misses can be initiated. We then systematically control the number of misses that are prefetched, the timeliness of these prefetches, and the number of umused prefetches. We validate the accuracy of our approach by comparing it to one based on a Markov prefetch algorithm. This allows us to measure the potential benefit that any application can receive from prefetching and to analyzed application behaviour under conditions that cannot be explored with any known prefetching algorithm. Next, we analyze a system parameter that is vital to prefetching performance, the line transfer interval, whish is the number of processor cycles required to transfer a cache line. This interval is determined by technology and bandwidth. We show that under ideal conditions, prefetching can remove nearly all of the stalls associated with cache misses. Unfortunately, real processor implementations are less than ideal. In particular, the trend in processor frequency is outrunning on-chip and off-chip bandwidths. Today, it is not uncommon for processor frequency to be three or four times bus frequency. Under these conditions, we show that nearly all of the performance benefits derived from prefetching are eroded, and in many cases prefetching actually degrades performance. We carry out quantitative and qualitative analyses of these tradeoffs and show that there is a linear relationship between overall performance and three metrics: percentages of misses prefetched, percentage of unused prefetches, and bandwidth.
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