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A new non-data-aided signal-to-noise ratio estimator for QPSK modulations in additive white Gaussian noise is proposed. It uses a simplified structure to achieve a good performance with less computational complexity. Simulation results show that the new estimator has smaller bias than existing estimators. The small bias and low computational complexity make it useful for practical applications.
A modified method used in gross error detection and data reconciliation is introduced in this paper. The modified method combines NT (Nodal Test) method and SEGE (simultaneous estimation of gross errors) method to find nodes with gross error. The proposed method can decrease the number of combination and increase computation efficiency. Simulation results on a steam metering system verify the effectiveness...
This paper studies the history of Diffusion Theory, put forward two new concepts of Tarde - Rogers Hypothesis and "Ryan - Gross" Paradigm. It's other theoretical significance is that introducing the classic hypothesis and paradigm of Diffusion Theory into Network News Communication and obtaining an empirical support. As for it's methodology, this paper puts forward some theoretical hypotheses...
An upper bound for the smallest period of the Fibonacci module sequence is obtained, which is 6N, and more accurate and convenient than the current results. Since the smallest period of the Fibonacci module sequence is twice of that of two-dimensional Arnold transformation, the upper bound for the smallest module period of Arnold transformation is naturally 3N. It is a great advance compared with...
Aiming to increase the proportion of the samples that has been determinate classified in Naive Credal Classifier, this paper improves conservative inference rule and proposes an incomplete data classification model based on relaxed conservative inference rule. Simulation results of comparative experiment with Naive Bayesian Classifier and Naive Credal Classifier verify the effectiveness of this classification...
The present work deals with the estimation of the average floc size of fine sediment particles using sedimentation data. Through particle size distribution tests of sediment under dispersion and flocculation situation, the criticle flocculation particle size was determined as 15μm. By theoretical analysis, floc sedimentation velocity formula was built based on the zero density flux at any cross section...
Is there any relationship between the historical volatility and the implied volatility in China's warrant market? Based the price data of 14 warrants in China's stock market, we found the answer is yes somewhat. It suggests that implied volatility can be taken as reference for the prediction of future fluctuation of stock prices. Despite the fact that implied volatility and historical volatility is...
In recent years, the GMS countries are becoming the hot point of the direct investment. The total volume of investment from Yunnan grows increasingly. But in the meanwhile, the risk of the host country is hindering the investing countries' positivity. The article takes the SME of Yunnan for example, focusing on two sides, one is the forewarning system, another is the management system, and combining...
Based on the principle of Mahalanobis distance discriminant analysis, the discrimination of influential degree of the different index to optimization of supporting programs for deep foundation pit is taken into account, using the weights obtained by the analytic hierarchy process to modify the Mahalanobis distance, by the new calculation method of covariance matrix, the weighted distance discreminant...
In order to achieve sensorless control for permanent magnet synchronous motor (PMSM), an observer based on model reference adaptive system (MRAS) is designed to estimate the rotor speed according to the mathematic model. A speed sensorless vector control system is established and simulated with Simulink. Simulation results show that the MRAS-based control system, which is able to implement the speed...
This paper presents a revised approach for estimating time-varying Origin-Destination flows in urban networks. This approach lend itself to a formulation as state-space model, and constructs an additional set of system observation constraints with estimated intersection turning flows to improve the system observability. Since there may exist errors in DTA or simulation models, this approach further...
The paper makes further research on estimating the parameters of the asymmetrical model describing effect of nutrient base on present literature, and provides a new method for estimating parameters that this method combines one-dimension search of optimization theory and multiple linear regression. The method not only overcomes the faultiness of estimation methods in existing literature, but also...
This paper develops a class of jump stochastic volatility threshold model of VaR Estimation from a Bayesian viewpoint. Bayesian inferences of the unknown parameters are obtained with respect to a subjective prior distribution via Markov chain Monte Carlo(MCMC) method, MCMC algorithm and the value at risk(VaR) predictive are also developed. Based on simulation, if the jump is not Considered, the value...
Credit evaluation is the basis for business decision-making. While the feasibility of credit model will directly influence the risk of deals. The designation of credit model with high reliability will make great sense for the progress of e-business technology. According to its fuzzy characters, a credit evaluation framework based on multivariable fuzzy reasoning is designed, which describes credit...
To find effective estimations of tail dependence, we present the estimators of upper tail dependence coefficient by using survival copula. We research to two problems by using the samples from t-copula. Firstly, do the estimators estimate effectively the upper tail dependence coefficients of copula? Which is the best among the estimators? Secondly, if sample isn't from true distribution, do the estimators...
Regarding order arrival obeying Poisson flow and general service distribution of single picking servicer as M/G/1 random service system, the efficiency optimal problem of manual order picking system is studied. Picking route stochastic model under random storage S-type picking condition is built. It makes model approximation calculation with simulation result under order random arrival frequencies...
Minimum covariance spectrum (MCS) estimation method is not robust in alpha stable distribution because of no finite covariance. A pseudo-power spectrum estimation method based on fractional low-order covariance (FLOC) matrix is proposed in this paper to improve MCS estimation method. The pseudo-power of a frequency point can be obtained by using FLOC matrix, and its pseudo-power spectrum (PPS) can...
The former maneuvering target tracking model is based on deterministic system. But the actual fact is the parameter and structure of system often change at random, which make the tracking system dynamic with the indeterminacy of structure and parameter. Use random changing theory and sensor management technique, and design the changing tracking model of system, considering fully the changing of state...
Background subtraction is a traditional method for detecting objects in stationary background. However, this traditional method is difficult to detect objects accurately in the real world, because the background is usually cluttered and not completely static. In this paper, we propose an object detection approach using Ant Colony System (ACS) in a MAP-MRF framework. For object segmentation, a MAP-MRF...
Environmental carrying capacity is one of the most critical indicators in tourism management of scenic areas, such as forest parks. In this study, the overall tourism environmental capacity (TEC) of Jiufeng National Forest Park was calculated by using the logistic model. Recommendations for the park management were provided based on the results. Further more, some ideas for integrating overall TEC...
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