the paper investigates TCP-friendly video streaming over wireless channel using forward-error-correction (FEC). A FEC scheme is used as an intra-protection control based on Hamming code. Coded BPSK scheme is applied o...
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the paper investigates TCP-friendly video streaming over wireless channel using forward-error-correction (FEC). A FEC scheme is used as an intra-protection control based on Hamming code. Coded BPSK scheme is applied over AWGN wireless channel to be robust against frequent packet loss. For this purpose, we propose variable frame rate based on TCP-friendly rate control (VFR-TCP) model. the model estimates the predicted frame rate for MPEG video streaming. Quality of service (QoS) is also accounted for the predicted quantizer scale Q if the network throughput is assumed to be equal the available bandwidth. Simulation results show that the VFR-TCP model increases tolerance to packet loss due to channel bit errors and achieves a good quality
Many large scale autonomous systems based on a large number of interacting agents in a structured physical environment have emerged in diverse areas such as biology, ecology or finance. Inspired by the desire to bette...
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ISBN:
(纸本)1424409535
Many large scale autonomous systems based on a large number of interacting agents in a structured physical environment have emerged in diverse areas such as biology, ecology or finance. Inspired by the desire to better understand and make the best out of such systems, we model them in order to gain insight, predict the future and control it partially if not fully. In this paper, we present a stochastic approach to modeling such systems based on G-networks. We propose two methods which deal with cases where complete or incomplete world knowledge is available. We use strategic military planning in urban scenarios as an example to demonstrate our approach. Our results suggest that this approach tackles the problem of modeling autonomous systems at low computational cost. Apart from offering numerical estimates of various outcomes, the approach helps us identify the parameters or characteristics that have the greatest impact on the system most and allows us to compare alternative strategies
A new bounded-error approach for the identification of discrete time hybrid systems in the piece-wise affine (PWA) form is introduced. the PWA identification problem involves the estimation of the number of affine sub...
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A new bounded-error approach for the identification of discrete time hybrid systems in the piece-wise affine (PWA) form is introduced. the PWA identification problem involves the estimation of the number of affine submodels, the parameters of affine submodels and the partition of the PWA map from data. By imposing a bound on the identification error, we formulate the PWA identification problem as a MIN PFS problem (partition into a minimum number of feasible subsystems) and propose a greedy clustering-based method for tackling it. the proposed approach yields to better results than the greedy randomized relaxation algorithm used in previous methods. Also, it is not sensitive to the overestimation of model orders and changes in the tuning parameters and therefore finding a right combination of the tuning parameters of the algorithm to get a model with prescribed bounded prediction error is simple
Detection of outliers is one of the data pre-processing tasks. In all the applications, outliers need to be detected to enhance the accuracy of the classifiers. Several different techniques, such as statistical, dista...
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Detection of outliers is one of the data pre-processing tasks. In all the applications, outliers need to be detected to enhance the accuracy of the classifiers. Several different techniques, such as statistical, distance-based and deviation-based outlier detection exist to detect outliers. Many of these techniques use filter method. A wrapper method using the concept of instance typicality may also be used to detect outliers. this paper deals with a new wrapper method that builds an initial model using neural networks and treats values at the output of neurons in the output layer as the typicality scores. Instances with lowest output values are treated as potential outliers. In addition, the method is also useful to build compact and accurate classifiers by selecting a few most typical instances resulting in significant reduction in storage space. the method is generic and thus can also be used for instance selection with any kind of classifiers. Resultant compact models are useful for imputation of missing values.
Stock market prediction has always been, in the past and at present, an intriguing issue. In this paper, an attempt is made at predicting the Standard & Poor9;s (S&P) 500 returns on a daily and weekly basis...
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Stock market prediction has always been, in the past and at present, an intriguing issue. In this paper, an attempt is made at predicting the Standard & Poor's (S&P) 500 returns on a daily and weekly basis by using only historical price data. Two different types of prediction models are used for the prediction task: the auto-regressive (AR) and the neural network (NN) models. these two models are used in four different prediction systems. the first two prediction systems consist of either an AR model or a NN model. the next two prediction systems represent the novelty of the approach used in this paper. A multiple-model approach is proposed, together withthe use of a trend classification algorithm, to predict the S&P 500 returns. three models (either AR or NN) are used in each of the systems, with each model used to represent one of the three market trends (bear, choppy and bull). A decision rule is used to select one prediction from the three models, and one of two trading rules is used to make trading decisions. three experiments were carried out to select appropriate parameters for the three-model systems. Evaluation of the models based on ARR after commission showed that the system consisting of three NNs was able to obtain approximately two times as much return as the buy-and-hold strategy in the test period when used in weekly predictions. Furthermore, the results in this paper show that non-linear systems performed better than linear ones, and three-model systems performed better than single-model ones
the strategy of data fusion has been applied in threat prediction and situation awareness and the terminology has been standardized by the Joint Directors of Laboratories (JDL) in the form of a so-called JDL data fusi...
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ISBN:
(纸本)1424409535
the strategy of data fusion has been applied in threat prediction and situation awareness and the terminology has been standardized by the Joint Directors of Laboratories (JDL) in the form of a so-called JDL data fusion model, which currently called DFIG model. Higher levels of the DFIG model call for prediction of future development and awareness of the development of a situation. It is known that Bayesian network is an insightful approach to determine optimal strategies against asymmetric adversarial opponent. However, it lacks the essential adversarial decision processes perspective. In this paper, a highly innovative data-fusion framework for asymmetric-threat detection and prediction based on advanced knowledge infrastructure and stochastic (Markov) game theory is proposed. In particular, asymmetric and adaptive threats are detected and grouped by intelligent agent and hierarchical entity aggregation in level 2 and their intents are predicted by a decentralized Markov (stochastic) game model with deception in level 3. We have verified that our proposed algorithms are scalable, stable, and perform satisfactorily according to the situation awareness performance metric
Order-k Markov model can be used in many fields such as natural language understanding, coding, mobile path prediction and so on to make prediction and then control. But the model has to face the problem of state spac...
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Order-k Markov model can be used in many fields such as natural language understanding, coding, mobile path prediction and so on to make prediction and then control. But the model has to face the problem of state space expansion. Taking the mobile path prediction as the research background, the paper firstly proposes a step-k Markov model and validates its feasibility. Secondly, a hybrid Markov predictor model is put forward based on the step-k Markov model. the complexity of the hybrid Markov model is O(N) while the order-k Markov model is O(N 2 ). And the memory demand of the hybrid Markov model is O(N 2 ) while order-k Markov model is O(N 3 ). Finally, it is proved that the hybrid Markov predictor can get close performance with order-k Markov predictor at much lower expense by conditional entropy analysis and user mobility data analysis. Also it can alleviate the zero probability problem in order-k Markov model to some extent. the hybrid Markov predictor is more practical than order-k Markov predictor under WLAN
this paper analyses stock market price prediction based on a hierarchical cerebellar model arithmetic controller (HCMAC) neural network. Applications using stock market price prediction tools are required to be adapti...
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this paper analyses stock market price prediction based on a hierarchical cerebellar model arithmetic controller (HCMAC) neural network. Applications using stock market price prediction tools are required to be adaptive to new incoming data as well as have fast learning capabilities. Current popular neural networks are based on the Multi Layer Perceptron (MLP) structure which has low memory consumption and has a fast processing speed however the performance of the MLP deteriorates as the network expands. An HCMAC structure uses a direct memory mapping technique which would perform consistently fast independent of size of network. the drawback is a huge amount of memory is required to perform direct mapping. this can be reduced by using self-organizing techniques to optimize the clusters during each training cycle. the accuracy of the output can be controlled based on the values set in the cyclic self-organizing module. the cyclic self-organizing HCMAC (CSOHCMAC) combines boththe HCMAC and cyclic self-organizing modules to create a neural network model that would be robust and fast as well as flexible to adapt to changes
When developing a product line the knowledge about the variation degree is of vital importance for development, maintenance and evolution of a product line. In this paper we focus on the variation degree of product li...
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ISBN:
(纸本)3540289364
When developing a product line the knowledge about the variation degree is of vital importance for development, maintenance and evolution of a product line. In this paper we focus on the variation degree of product line feature models, considering different types of variability and dependency relationships between features.
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