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Simulated annealing algorithm is a heuristic algorithm, proposed one approximation algorithm kind of solving optimization combinatorial problems inspired by objects in the annealing process by heating crunch. The algorithm is superior to the traditional greedy algorithm, which avoiding falling into local optimum and reach global optimum. In road network planning, often encountered some kind of traffic...
Atmospheric turbulence leads to a stochastic process of optical intensity and phase of beam. Thus, errors of departure angle detection are induced. In the paper, a new method to modify of departure angle detection is introduced to Free Space Optical Communications. Based on the phase retrieval, the new method only needs the intensity of the image on the focal plane to calculate the revising phase...
The application of PMU measurements and collocated control to damp inter-area oscillations with coordinated DC lines and static var compensators (SVCs) is investigated. The closed loop eigenvalues are excluded from a region of the complex plane guaranteeing that low frequency modes must be damped. A 16-machine, 68-bus study system reinforced with four DC lines or two DC lines and two SVCs is considered...
Turbo Code has been claimed as an error correction code that achieves Shannon limit. It has been proposed in many communication systems standards. Performance of Turbo Code under different channel condition is a key factor that should be considered because of requirements of applications. In this paper, we introduced the theory of Turbo Code including a practical Turbo Decoding algorithm - Log-MAP...
Using nanofabrication technologies, it is possible to pattern materials on the scale of the wavelength of light, dramatically altering its propagation. Here we discuss our results in three application areas of nano- and microphotonics.
In chaos secure communication system, to separate effectively chaos and harmonic signal is an important way of testing systematic confidential performance. In recent years, the time-frequency analysis theory is more and more mature, effective time-frequency analytical algorithms are emerging constantly. The paper starts with the time-frequency character analysis of the chaos, the noise and the harmonic...
Advanced personalized e-applications require comprehensive knowledge about their user's preference in order to provide individual product recommendations and custom-tailored product offers. Much research has been conducted using Web logs to infer user preferences and predict users' behavior. However, little research measures the stability of user preferences over time. In this paper, the index named...
Heterodyne efficiency in free-space optical communications based on heterodyne detection is degraded by the aberrations of the optics antenna used for reception of optical beams. The evolution of heterodyne efficiency with the change of rms of primary aberrations is investigated. It is shown that heterodyne efficiency decreases gradually with increasing primary aberrations. The comparison shows that...
In this paper, the synergy of the channel coding and aperture averaging is applied to the downlink optical channel for the low earth orbit (LEO) satellite. Bit error rates (BER) of the convolutional code and low-density parity code (LDPC) are evaluated versus different diameters for the optical systems with avalanche photodiode (APD) receivers. Results indicate that when the temporal correlation time...
In this paper mainly describes a quartz tuning fork temperature sensor based on bending vibration. The main working components of quartz tuning fork temperature sensor are quartz tuning fork and driving circuit, according to the piezoelectric effect principle of quartz crystal, researching on correlative incentive mode, selecting cut type and setting electrodes reasonably, and applying finite element...
In recent years, the crisis caused by mass incidents occurred from time to time, having strongly affected the social stability. Based on different periods of crisis, leaders should try to reduce the occurrence of mass incidents crisis by using different methods of leadership, changing leadership path and adopting the "five forces" leadership model in order to ensure the overall stability...
According to the Economic Theory, this paper established a Game Model to analyze the reasons for the Construction Payment in Arrears, obtained a method to deal with the corresponding problem under the premise of the effective government supervision and set up a framework to achieve the Quantitative Analysis.
An adaptive protection scheme using digital relays with a communication network is proposed for the protection of the distributed systems. The impact of distributed generators on protection coordination is first discussed. Then, an adaptive protection scheme is proposed for distributed systems with distributed generation (DG). Simulated results on an actual distribution system show that the proposed...
A novel scheme based on generalized leakage inductance (GLI) to distinguish the inrush current from the internal fault current in the power transformer is proposed. By eliminating the mutual flux linkage in the transformer loop equation and adopting the trapezoid principle, the GLI is calculated in the real time. According to the difference between the GLI and the leakage inductance obtained from...
This paper develops a systematic procedure of designing global power system stabilizers (GPSSs) based on collocated control to enhance the damping during interarea oscillations. The availability of remote signals from phasor measurement units (PMUs) enables the wide-area control in large scale systems. The closed loop eigenvalues are excluded from a region of the complex plane by the collocated control...
Optical pulse temporal spreading can restrict the capability of space optical communication. This paper provides most of the details of Monte Carlo simulation method about pulsed laser propagation in inferior atmospheric layer. Several conclusions of this work are obtained. One is that the temporal spreading of pulsed laser is strongly influenced by propagation length and aerosol concentration. Another...
The management of distributed energy resources using standard Information and Communication Technology (ICT) has attracted a lot of attentions recently. With high integration of ICT infrastructure, security has gained tremendous importance for energy distribution and energy automation systems. The cryptographic techniques play critical roles in achieving the information security goals. This paper...
in order to achieve the reliable decoding when the real-time video compression bit streams are transmitted in radio channel, the effective channel code method is given. It is based on the Turbo product codes with AHA4501. The performance of its delay time and error correction is evaluated. The selection of block size, the iteration number and frame sync header and is described. And the method has...
The continuous-state fault tree (CSFT) is used for reliability analysis for the degradation performance of SLD. Firstly, the degradation performance of SLD is analyzed and the methods of building CSFT are proposed. Based on CSFT, the formula for reliability is deduced. Secondly, the reliability quantitative analysis of SLD is introduced based on the building CSFT of SLD. Thirdly, the reliability curve...
Remote-sensing technology has special advantages in estimating forest carbon storage and biomass on the ground. The paper summarizes three main methods of estimating forest carbon storage by using remote-sensing technology, namely, multielement regression analytical method, artificial neural network method and mathematical modeling method. Also the advantages and disadvantages of each method are explained...
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