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Base bleed propellant is an important component of the increasing rang projectile using base bleed technology. Unsteady strongly combustion leads to extinguish, reignition or critical state which produce an effect on rang dispersion. The burning behavior is determined by the initial pressure of combustion chamber and the maximum pressure decay rate, which was investigated by simulation experimental...
For better manipulability, a criterion in the form of a quadratic function is presented for the self-motion planning (SMP) of redundant manipulators with no target-configuration assigned. Such SMP scheme could automatically select the desirable configuration so that the manipulator could be more flexible and maneuverable. As physical limits generally exist in actual redundant manipulators, both joint...
A nonlinear prediction model has been presented of PSO-ANN of monthly precipitation in rain season. It differs from traditional prediction modeling in the following aspects: (1) input factors of the PSO-ANN model of monthly precipitation were selected from a large quantity of preceding period high correlation factors, and they were also highly information-condensed by using the empirical orthogonal...
Following the thinking clue of the ensemble prediction in numerical weather prediction (NWP), a novel nonlinear artificial intelligence ensemble prediction (NAIEP) model for calculation wind speed of Mountain Darong in Guangxi has been developed based on the multiple neural networks with identical expected output created by using the genetic algorithm (GA) of evolutionary computation. The results...
Chaos of a new class of Hopfield neural networks is investigated. Numerical simulations show that the simple Hopfield neural networks can display chaotic attractors and limit cycles for different parameters. By virtue of horseshoes theory in dynamical systems, the rigorous computer-assisted verifications for chaotic behavior of the system for certain parameters is given, and also the quantitative...
Web-based mapping applications such as Google Maps or Virtual Earth have become increasingly popular. However, current map search is still keyword-based and supports a limited number of spatial predicates. In this paper, we build towards a natural language query interface to spatial databases to answer crime-related spatial queries. The system has two main advantages compared with interfaces such...
This paper proposes a new type of query for moving object trajectories -- continuous interval-based nearest neighbor (CINN) query. We clearly define the CINN in the context of streaming trajectory data. To efficiently process CINN queries, we first propose a spatial hashing algorithm (SH). Then we show theta new temporal hashing algorithm (TH) using speed constraints can save substantial computation...
An artificial neural network (ANN), a data driven modelling approach, is proposed to predict the algal bloom dynamics of the coastal waters of Hong Kong. The commonly used back-propagation learning algorithm is employed for training the ANN. The modeling is based on (a) comprehensive biweekly water quality data at Tolo Harbour (1982-2000); and (b) 4-year set of weekly phytoplankton abundance data...
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