Search

Using the C - C method to reconstruct the phase space of wind power time series, get the maximum wind power time series Lyapunov exponent, confirmed that the wind power time series have chaotic characteristics. Followed by the radial basis function (RBF) neural network model for wind power chaotic local multi-step prediction, results show that the prediction effect is better than that of the predicted effect of 48 hours for 24 hours.

Using melamine formaldehyde (MF) microspheres as hard templates and silica colloid as shell precursors, core-shell structures of silica-coated MF microspheres were prepared by the electrostatic adsorption process or spray drying inspired in-situ coating and drying process. Furthermore, nanometer- and micrometer-sized silica hollow spheres were obtained by calcinations in air. The influence of preparation methods and ratio of silica colloid to MF microspheres on the composition, the morphology and size of the core-shell intermediates and the hollow spheres were studied with FTIR, SEM and TEM techniques.

The parallel grooved multi-layer winding drum can wind rapidly and reliably compared to traditional multi-layer winding drum, because of the special groove which is generated by circular and helical motion. The present paper represented the key winding stage for parallel grooved drum was the helical motion in first circle on the second layer, and the stage was simulated in ADAMS under several factors as fleet angle, winding linear velocity and rope tension. Taguchi method was adopted to estimate the winding performance through two simulation outputs, including the time delay compared to ideal time and the sum of amplitude error during the delayed time. Experiment was applied by considering more factors than that in ADAMS, and the experiment results could verify the validity of simulation in ADAMS. The simulation and experiment results showed that the optimal winding performance could be obtained with certain combination of factors.

Only the basic wall thickness of drum is taken under consideration in traditional parallel grooved drum strength analysis, which is quite conservative for ignoring the thickness of the groove. So in this paper, it is aimed at comparing the strength simulation results for two drum models with and without the thickness of the groove and analyzing the stress distribution of the drum structure, which provides reference for the structure design and optimization of the drum.

The paper mainly studies the available transfer capability of wind farm incorporated power system, and proposes an on-line calculating method considering many uncertain factors. First based on continuation power flow, an improved algorithm of the key constraint by linear prediction is proposed so as to obtain deterministic ATC with the expansion power flow equation. Then Monte Carlo simulation is used which takes many uncertain factors into considerations, such as wind speed, the random fault of generators and lines, the fluctuation of generators and load, etc. With hierarchical clustering algorithm, the samples with the same key constraint can be divided into one category without repeatedly predicting key constraint, so the probabilistic ATC in all kinds of conditions can be got rapidly and precisely. Finally a case study demonstrates the validity and superiority of method proposed in this paper. The research could be a valuable reference to power market operations and wind farm planning.

Traffic overflow has great negative impact on normal traffic flow. Improper time setting and offset, even more right turn input traffic flow can cause this extreme phenomenon. In order to discover the intrinsic factor and relationship between overflow and signal setting, traffic flow incoming, we build the traffic flow model. This model takes two adjacent crosses as example, and to count the remained traffic flow queue length in given time interval. The simulation results prove our model’s feasibility. Our model well helps us to understand the overflow characteristics and to find the effective solution to conquer it in the future.

Optimal Velocity Model (OVM) is one of the typical car-following traffic flow models. The driver’s sensitivity factor in OVM is always constant in the past study, which does not fully comply with practical traffic flow characteristics. To gain a more actual and objective model, we propose a kind of heterogeneous drivers car-following optimal velocity model, i.e. HDOVM. In this model, the constant driver’s parameter is substituted with driver type function, and every car in the queue has a corresponding value. After stability analysis with Laplace transform state space method, we make many types cars in the traffic queue numerical simulation to prove our supposition , the simulation results after many times show that the HDOVM model is more practical than traditional ones. Considering the diversity of traffic flow composition should be one of the major factors to find out the reason of traffic jam.

The discrete element code, EDEM, has been employed to simulate the axial mixing of size-binary particles in rotary kiln. Number of contacts has been introduced to track the progress of mixing and number of contacts between different particles has been took as mixing index between different particles to analyze the degree of mixing The results show that the larger velocity of particles in active layer is the main reason for the mixing; axial displacement of smaller particles is due to penetration of smaller particles through the intervals between larger particles.

This paper attempts to summarize the findings of a large number of research papers concerning the application of intelligent optimization algorithms to ITS. A brief introduction to intelligence is included, for the benefit of readers unfamiliar with the techniques. Then it put emphasis on three kinds of intelligent optimization application in ITS, including ANN, GA and PSO. It should be noted first that each of the three subjects can prolong to a long paper, and second that there are also some other intelligent optimization method, such as fuzzy logic, ant colony, shuffle frog-leaping algorithm et.al.. On the constraint of time and paper volume, we only analyzed those three algorithms, their state-and-the-art use in ITS, and their future development trend.

If the big users electricity consumption kept the same, while comparing through grid direct-purchasing power with building the power plant and purchasing the power by grid, and then establish the profit and loss model and point to point mode. Finally, we need to demonstrate the economy of direct power purchase through the example and value.

Based on the microscope phase-field model，the evolution of atom morphology, the long range order(lro) parameter and concentration can be gotten, and atomic clustering and ordering during the precipitation process of Ni-Cr-Al alloy could be obtained. The Ni-14at.%Cr-15.5at.%Al alloy is studied and the temperature of precipitation are 973K. It was showed that the ordering of both Al and Cr atoms take place simultaneously during the precipitation process of Ni-Al-Cr alloy, Cr atoms transfer to the boundaries of L12 phases, the domain of rich Cr atoms are formed. At the boundaries of L12 phases, Cr atoms may substitute the Al sublattice, and the D022 phases are formed.