Iterative learning control algorithm is introduced in this paper to deal with delay in the networked control *** is applied to the networked control system for its simple structure and independence on the accurate ***...
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Iterative learning control algorithm is introduced in this paper to deal with delay in the networked control *** is applied to the networked control system for its simple structure and independence on the accurate *** delay and interference,the system model and detailed algorithm design process is *** by the Matlab demonstrate the effectiveness of the algorithm.
The Bayesian method has proven to be a powerful way of modeling inverse problems. The solution to Bayesian inverse problems is the posterior distribution of estimated parameters which can provide not only estimates fo...
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The Bayesian method has proven to be a powerful way of modeling inverse problems. The solution to Bayesian inverse problems is the posterior distribution of estimated parameters which can provide not only estimates for the inferred parameters but also the uncertainty of these estimations. Markov chain Monte Carlo (MCMC) is a useful technique to sample the posterior distribution and information can be extracted from the sampled ensemble. However, MCMC is very expensive to compute, especially in inverse problems where the underlying forward problems involve solving differential equations. Even worse, MCMC is difficult to parallelize due to its sequential nature—that is, under the current framework, we can barely accelerate MCMC with parallel computing. We develop a new framework of parallel MCMC algorithms-the Markov chain preconditioned Monte Carlo (MCPMC) method-for sampling Bayesian inverse problems. With the help of a fast auxiliary MCMC chain running on computationally cheaper approximate models, which serves as a stochastic preconditioner to the target distribution, the sampler randomly selects candidates from the preconditioning chain for further processing on the accurate model. As this accurate model processing can be executed in parallel, the algorithm is suitable for parallel systems. We implement it using a modified master-slave architecture, analyze its potential to accelerate sampling and apply it to three examples. A two dimensional Gaussian mixture example shows that the new sampler can bring statistical efficiency in addition to increasing sampling speed. Through a 2D inverse problem with an elliptic equation as the forward model, we demonstrate the use of an enhanced error model to build the preconditioner. With a 3D optical tomography problem we use adaptive finite element methods to build the approximate model. In both examples, the MCPMC successfully samples the posterior distributions with multiple processors, demonstrating efficient speedups com
Large amounts of data are transported to the ground in the process of logging and limitations of cable bandwidth, so ultrasonic log data need to be compressed in the downhole when logging. In this case, this paper put...
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ISBN:
(纸本)9781479964253
Large amounts of data are transported to the ground in the process of logging and limitations of cable bandwidth, so ultrasonic log data need to be compressed in the downhole when logging. In this case, this paper put forward a new lossless coding structure UWLC to compress the ultrasonic logging data. This structure of UWLC is designed to encode the data to close achieve the effect of envelope detection. The UWLC has a strong ability to track data amplitude. In ultrasonic log data compression case, comparing to traditional Golomb-rice, adaptive Golomb-rice and LZW compression algorithms, UWLC has higher compression ratio.
In RFID systems, the reader usually identifies all the RFID tags in the interrogation region with the maximum power. However, some applications may only need to identify the tags in a specified area, which is usually ...
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ISBN:
(纸本)9783319115689
In RFID systems, the reader usually identifies all the RFID tags in the interrogation region with the maximum power. However, some applications may only need to identify the tags in a specified area, which is usually smaller than the reader's default interrogation region. In this paper, we respectively present two solutions to identify the tags in the specified area. The principle of the solutions can be compared to the picture-taking process of a camera. It first focuses on the specified area and then shoots the tags. The design of the two solutions is based on the extensive empirical study on RFID tags. Realistic experiment results show that our solutions can reduce the execution time by 46% compared to the baseline solution.
作者:
Adamopoulos, PanagiotisNYU
Leonard N Stern Sch Business Dept Informat Operat & Management Sci New York NY 10003 USA
This paper proposes a number of studies in order to move the field of recommender systems beyond the traditional paradigm and the classical perspective of rating prediction accuracy. We contribute to existing helpful ...
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ISBN:
(纸本)9781450323512
This paper proposes a number of studies in order to move the field of recommender systems beyond the traditional paradigm and the classical perspective of rating prediction accuracy. We contribute to existing helpful but less explored recommendation strategies and propose new approaches targeting to more useful recommendations for both users and businesses. Working toward this direction, we discuss the studies we have conducted so far and present our future research plans. The overall goal of this research program is to expand our focus from even more accurate rating predictions toward a more holistic experience for the users, by providing them with non-obvious but high quality recommendations and avoiding the over-specialization and concentration bias problems. In particular, we propose a new probabilistic neighborhood-based method as an improvement of the standard k-nearest neighbors approach, alleviating some of the most common problems of collaborative filtering recommender systems, based on classical metrics of dispersion and diversity as well as some newly proposed metrics. Furthermore, we propose a concept of unexpectedness in recommender systems and operationalize it by suggesting various mechanisms for specifying the expectations of the users and proposing a recommendation method for providing the users with unexpected but high quality personalized recommendations that fairly match their interests. Besides, in order to generate utility-based recommendations for Massive Open Online Courses (MOOCs) that better serve the educational needs of students, we study the satisfaction of users with online courses vis-a-vis student retention. Finally, we summarize the conclusions of the conducted studies, discuss the limitations of our work and also outline the managerial implications of the proposed stream of research.
The importance of skyline and dominance relationship analysis has been well recognized in multicriteria decision-making applications. In this paper, we propose the problem of "Finding Skyline with Customer Prefer...
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ISBN:
(纸本)9781509001897
The importance of skyline and dominance relationship analysis has been well recognized in multicriteria decision-making applications. In this paper, we propose the problem of "Finding Skyline with Customer Preferences and Cost Constraints", which utilizes the concept of dominance for business analysis from a microeconomic perspective. Our problem aims to discover the dominance relationship between products and potential customers. Given a set of customer preferences, we want to help the company to design set of competitive products so that the products can satisfy as many customer requirements as possible and the cost of producing the products is within a specified threshold. By "competitive products" we mean that the products cannot be dominated by other products in the market. We formally define the problem and discuss the difficulty of the problem. We also present the foundation and the intuition of our pruning methods. Then we proposed three efficient algorithms that utilize our pruning methods to address the problem. In addition, we also prove the correctness of our proposed algorithms.
In this communication, we have investigated the effect of trigonometric mutation strategy of Differential Evolution (DE) algorithm for the design of hardware efficient multiplier-less Finite duration Impulse Response ...
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ISBN:
(纸本)9781510804524
In this communication, we have investigated the effect of trigonometric mutation strategy of Differential Evolution (DE) algorithm for the design of hardware efficient multiplier-less Finite duration Impulse Response (FIR) filter. The resulting filter performance has been compared and properly analyzed with the one designed by rand/1 mutation technique of DE and other existing multiplier-less structures from various angles. Finally, the design efficiency of our proposed filter over the other models has been firmly established by listing a number of performance parameters.
We consider virtual circuit routing protocols, with an objective of minimizing energy, in a network of components that are speed scalable, and that may be shutdown when idle. We assume that the speed s of a link is pr...
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ISBN:
(纸本)9781611973389
We consider virtual circuit routing protocols, with an objective of minimizing energy, in a network of components that are speed scalable, and that may be shutdown when idle. We assume that the speed s of a link is proportional to its load, and assume the standard model for component power, namely that the power is some constant static power σ plus s~α, where typically α∈ [1, 1, 3]. We give a polynomial-time offline algorithm for multicommodity routing, that has approximation ratio O(logα k), where k is the number of demand pairs. This is obtained as a combination of three natural combinatorial algorithms. The key step of the algorithm design is a random sampling technique that we call hallucination, which is reminiscent of the Sample-Augment framework for solving Buy-at-Bulk type problems, and sampling in cut-sparsification algorithms. The analysis of the approximation ratio is then a direct consequence of the flow-cut gap for multicommodity flow. The algorithm extends rather naturally to an online algorithm, which we show has competitive ratio O{top}~(log~(3α+1) k). The analysis of the online algorithm introduces a natural "priority" multicommodity flow problem, and bounds the priority multicommodity flow-cut gap-this might also be of independent interest. We also explain how our hallucination technique can be used to achieve an (O(log km), O(log km)) bicriteria approximation result for the problem of buying a minimum cost collection of unit-capacitated edges to support a concurrent multi-commodity flow, where m is the number of links in the network.
Only one harmony vector is obtained in each iteration in the classical harmony search algorithm, which affects its search ability. In view of this, we propose an improved harmony search algorithm in this paper. In our...
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ISBN:
(纸本)9781784660529
Only one harmony vector is obtained in each iteration in the classical harmony search algorithm, which affects its search ability. In view of this, we propose an improved harmony search algorithm in this paper. In our approach, an equivalent number of harmony vectors with a population size are obtained in each iteration, and the newly generated harmony vectors are put into the harmony memory array. Then, all harmony vectors are sorted according to fitness from high to low, and the first half individuals are removed into the next generation of populations. Experimental results show that the proposed approach is obviously superior to the classical one under both the same number of iterations and the same running time, which reveals our approach can effectively extract the characteristics of excellent individuals in the population and obtain satisfactory optimization results.
Government and commercial customers are increasingly interested in robust, reusable flight software. For many spacecraft, Attitude Determination and Control Subsystem (ADCS) contributes a significant portion of the FS...
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ISBN:
(纸本)9781479916191
Government and commercial customers are increasingly interested in robust, reusable flight software. For many spacecraft, Attitude Determination and Control Subsystem (ADCS) contributes a significant portion of the FSW. Thus refinements to ADCS code pay dividends for code development and reuse. Sierra Nevada Corporation (SNC) has recently developed an ADCS model and code set that follows model based design techniques. It uses Simulink for algorithm design and verification, a modular parameter database to customize mission profiles, and automatic code generation to create production quality embedded software. The code will be used on a LEO Earth imaging nanosat. This paper presents an overview of the algorithms, model architecture, parameter database, and code generation process.
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