Generalized software packages endowed with a large spectrum of functionalities are often underutilized because users are not always aware of all the functionalities. It is hence desirable to display personalized infor...
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Generalized software packages endowed with a large spectrum of functionalities are often underutilized because users are not always aware of all the functionalities. It is hence desirable to display personalized information about the package. Though popular in web-based applications, personalization as a field of research in the design of generalized software packages is rare. This article develops a semi-Markov model of user navigation and an adaptive dynamic programming formulation to select high-utility software functions (states) for dynamically displaying them to a user. The personalization algorithm considers the interests of the software designers, the past users, and the current user. Frequency of visit to a state and the holding time in the state together determines the utility of the state. The personalization algorithm considers the interests of the software designers, the past users, and the current user. The algorithm is built in a demo package of ActiveX Servers and Controls. Graduate students tested the package. Pareto analysis and tests of hypothesis conducted on the test results indicate that the users did utilize the information on the displayed personalized software functions.
Real-time logics are popular specification languages for reasoning about systems intended to meet timing constraints. Numerous formalisms have been proposed with different underlying time models that can be characteri...
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Real-time logics are popular specification languages for reasoning about systems intended to meet timing constraints. Numerous formalisms have been proposed with different underlying time models that can be characterized along two dimensions: dense versus discrete time and point-based versus interval-based. We present monitoring algorithms for the past-only fragment of metric temporal logics that differ along these two dimensions, analyze their complexity, and compare them on a class of formulas for which the point-based and the interval-based settings coincide. Our comparison reveals similarities and differences between the monitoring algorithms and highlights key concepts underlying our and prior monitoring algorithms. For example, point-based algorithms are conceptually simpler and more efficient than interval-based ones as they are invoked only at time points occurring in the monitored trace and their reasoning is limited to just those time points.
Traditional Earley parsers operate in two phases: first recognizing the input, then constructing the forest of parse trees. Practically speaking, this quirk makes it awkward to use in a compiler-compiler, because sema...
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Traditional Earley parsers operate in two phases: first recognizing the input, then constructing the forest of parse trees. Practically speaking, this quirk makes it awkward to use in a compiler-compiler, because semantic actions attached to rules are only executed after the fact. We address this problem by identifying safe Earley sets, points during the recognition phase at which partial parse trees can be constructed;this means that semantic actions may be executed on the fly. A secondary benefit is that Earley sets can be deleted during recognition, resulting in a substantial savings of both space and time.
We designed, implemented, and tested a real-time flexible controller for manipulating different types of robots and control algorithms. The robot-independent, IBM PC-based multiprocessor system contains a DSP56001 mas...
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We designed, implemented, and tested a real-time flexible controller for manipulating different types of robots and control algorithms. The robot-independent, IBM PC-based multiprocessor system contains a DSP56001 master controller, six independent HCTL-1100 joint processors for accurate robotic joint control, and an interface computer board for processor communication, The joint processors operate in four user-defined modes and can be connected directly to an incremental optical encoder, which accommodates specialized applications and eliminates extra hardware.
A self-stabilizing algorithm cannot detect by itself that stabilization has been reached. For overcoming this drawback Lin and Simon introduced the notion of an external observer, i.e., a set of processes, one being l...
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A self-stabilizing algorithm cannot detect by itself that stabilization has been reached. For overcoming this drawback Lin and Simon introduced the notion of an external observer, i.e., a set of processes, one being located at each node, whose role is to detect stabilization. We propose here a less expensive approach, where there is a single observing process located at a unique node. This process is not allowed to detect false stabilization and it must eventually detect that stabilization is reached. Moreover it must not interfere with the observed self-stabilizing algorithm. Our result is that there exists such an observer for any problem on a distinguished network having a synchronous self-stabilizing solution. Note that our proof is constructive.
The problem of estimating the state of a nonlinear stochastic plant is considered. Unlike classical approaches such as the extended Kalman filter, which are based on the linearization of the plant and the measurement ...
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The problem of estimating the state of a nonlinear stochastic plant is considered. Unlike classical approaches such as the extended Kalman filter, which are based on the linearization of the plant and the measurement model, we concentrate on the nonlinear filter equations such as the Zakai equation. The numerical approximation of the conditional probability density function (pdf) using ordinary grids suffers from the "curse of dimension" and is therefore not applicable in higher dimensions. It is demonstrated that sparse grids are an appropriate tool to represent the pdf and to solve the filtering equations numerically. The basic algorithm is presented. Using some enhancements it is shown that problems in higher dimensions can be solved with an acceptable computational effort. As an example a six-dimensional, highly nonlinear problem, which is solved in real-time using a standard PC, is investigated.
A method of visual navigation by stereoimages for autonomous underwater vehicles is suggested. Two modifications of the method are considered. The first one is based on integration of measurement data of onboard navig...
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A method of visual navigation by stereoimages for autonomous underwater vehicles is suggested. Two modifications of the method are considered. The first one is based on integration of measurement data of onboard navigation system with visual data. The second modification relies on the use of a six-cloud computation scheme. Results of computational experiments with model data are presented.
Computational modeling of biological systems is becoming increasingly important in efforts to better understand complex biological behaviors. In this review, we distinguish between two types of biological models-mathe...
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Computational modeling of biological systems is becoming increasingly important in efforts to better understand complex biological behaviors. In this review, we distinguish between two types of biological models-mathematical and computational which differ in their representations of biological phenomena. We call the approach of constructing computational models of biological systems 'executable biology', as it focuses on the design of executable computer algorithms that mimic biological phenomena. We survey the main modeling efforts in this direction, emphasize the applicability and benefits of executable models in biological research and highlight some of the challenges that executable biology poses for biology and computer science. We claim that for executable biology to reach its full potential as a mainstream biological technique, formal and algorithmic approaches must be integrated into biological research. This will drive biology toward a more precise engineering discipline.
The interest in improving the efficiency of photovoltaic (PV) system has emerged because of increasing the number of home-based or small-scale PV power system. However, the home-based PV system is vulnerable to the no...
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The interest in improving the efficiency of photovoltaic (PV) system has emerged because of increasing the number of home-based or small-scale PV power system. However, the home-based PV system is vulnerable to the non-uniform operating conditions. Under such circumstances, multiple-local maximum power points (MPPs) occur on the power-voltage characteristics and an advanced control algorithm is required to track the global MPP. It is very difficult to provide a sophisticated control algorithm because of the non-linear characteristics of PV system. This study describes the potential to improve the efficiency of PV arrays under non-uniform operating conditions by using the conventional hill-climbing MPP tracking method in total cross tied (TCT) connected PV arrays, in which each group of series connected solar cells that belong to single bypass diode is interconnected. The various scenarios were tested and the results indicate that the efficiency of the proposed system is much higher than that of the same size of series-parallel (SP) PV array configuration.
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.
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