The Emeishan large igneous province in the western Yangtze Block was resulted from a mantle plume at end of the Middle Permian. Four super-large V-Ti-magnetite deposits and 10 large-medium Ni-Cu-(PGE) sulfide deposits...
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The Emeishan large igneous province in the western Yangtze Block was resulted from a mantle plume at end of the Middle Permian. Four super-large V-Ti-magnetite deposits and 10 large-medium Ni-Cu-(PGE) sulfide deposits have been explored in the Emeishan large igneous province. Precise age data indicated that these ore-bearing mafic-ultramafic intrusions were produced by the same mantle plume that caused the Emeishan flood basalts at 260 Ma±. The maficultramafic intrusion hosting V-Ti-magnetite deposits and Ni-Cu-(PGE) sulfide deposits are distinguished in localization, scale, rock-assemblages, components of rock-forming minerals. The Emeishan large province can be divided to Inner- and Outer-Zones. The Inner-Zone is marked by large thickness of the Emeishan flood basalts, large layered intrusions, mafic-ultrmafic intrusive bodies, low-Ti basalts, alkaline intrusions, and various mineralizations related to the mantle plume. The basalts become thinner and consist of high-Ti basalts in the Outer-Zone where fewer mafic-ultramafic bodies are exposed. Special and geochemical relationship between the two type of magmatic deposits and high- and low-Ti basalts,the study on petrogenetic links between the Ni-Cu-(PGE) sulfide deposits and the Emeishan flood basalts in the Yangliuping area indicate that the magmatic deposits formed in different dynamic stages of the mantle plume. The V-Ti-magnetite deposits are associated with the high-Ti basaltic magmas and related to fractional crystallization. In contrast, the Ni-Cu-(PGE) sulfide mineralization may be related to either the high- or low-Ti basaltic magmas and controlled by three factors: high degree partial melting of upper mantle, contamination of the lower crust, and fractional crystallization. The Ni-Cu-(PGE) sulfide deposits were formed earlier than the V-Ti-magnetite deposits.
The measurement uncertainty is often evaluated by a probabilistic approach, but such evaluation is not always adapted to imprecise measurement data. This paper focuses on the use of the evidence theory to evaluate the...
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The measurement uncertainty is often evaluated by a probabilistic approach, but such evaluation is not always adapted to imprecise measurement data. This paper focuses on the use of the evidence theory to evaluate the measurement uncertainty of imprecise neutrons data. A formula is presented to measure and calculate the measurement uncertainty of imprecise neutrons data coming from imprecise physical sensors and approximate estimations provided by experts, the validity of the formula is demonstrated by two examples. The formula can be applied to precise neutrons data too.
A method for learning the dynamic responses of a nonlinear power-amplifier with a radial basis function (RBF) neural network is presented. The training data of the RBF neural networks are samples of the input and outp...
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ISBN:
(纸本)0780386477
A method for learning the dynamic responses of a nonlinear power-amplifier with a radial basis function (RBF) neural network is presented. The training data of the RBF neural networks are samples of the input and output waveforms of the power-amplifier. A new training scheme employing efficient gradient-based optimization methods is developed to train the RBF neural networks model. Simulation results are presented to demonstrate the superiority of the RBF neural networks compared with recurrent neural networks and other networks.
A power system harmonic detection technique based on a frequency domain interpolation wavelet transform is proposed. Aiming at harmonic detection, a fast Fourier transform (FFT) can only detect integer harmonics; a sh...
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ISBN:
(纸本)0780386477
A power system harmonic detection technique based on a frequency domain interpolation wavelet transform is proposed. Aiming at harmonic detection, a fast Fourier transform (FFT) can only detect integer harmonics; a short time Fourier transform (STFT) can detect non-integer harmonics with low resolution; a wavelet transform can detect non-integer harmonics, but it has spectral aliasing and spectral leakage phenomena, which result in low resolution. This paper uses a frequency domain interpolation algorithm to detect a harmonic signal by choosing a Shannon wavelet. Simulation and comparative results obtained by three algorithms reveal that: the proposed method can effectively eliminate spectral aliasing, spectral leakage and the Gibbs phenomenon; it can precisely detect a harmonic signal, so it provides an effective means for power system harmonic analysis and detection.
This paper considers the problem of scheduling a fleet of identical vehicles to execute a set of freight orders in truckload quantities. Each freight order is given in terms of an origin and a destination and the numb...
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ISBN:
(纸本)0784406308
This paper considers the problem of scheduling a fleet of identical vehicles to execute a set of freight orders in truckload quantities. Each freight order is given in terms of an origin and a destination and the number of truckloads to be transported between them. The goal is to minimize the total cost of travel while completing all freight orders. Our work is the first to allow vehicles to be dispatched from a depot and discharged into another after service. We propose an algorithm that starts from an optimal solution to a network flow model which considers all data in the problem in parallel including unloaded travel costs, freight orders, depots, availability of vehicles and the vehicle receiving capacity at each depot. The network solution is then iteratively modified through heuristic operations and the routing of vehicles is determined, one at a time, based on the modified solution. A novel feature of the algorithm is the option of resolving the network model for scheduling the remaining vehicles.
Spectral drift of any origin consisting of detectors and nuclear electronics affects the long-term stability in a gamma-ray spectrometer, which is essential to maintaining the high quality of gamma energy spectraThe f...
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Spectral drift of any origin consisting of detectors and nuclear electronics affects the long-term stability in a gamma-ray spectrometer, which is essential to maintaining the high quality of gamma energy spectraThe feedback regulation according to the quantity of spectral drift can restore the system's stabilityA new algorithm for spectral drift calculation is given in this paperA digital logic unit is developed in a FPGA chip based on the algorithm, and a MCU coordinating with it can fast calculate the spectral drift within only less than 110 instruction periods.
Ion-beam-sputtering/mixing deposition was used to produce thin calcium phosphate coatings on titanium substrate from the hydroxyapatite target. The mixing beam could be either Ar + or N + ions. It was found that as-de...
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