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Based on the random finite set (RFS) framework and the probability hypothesis density (PHD) filter, the extended target PHD (ET‐PHD) filter is proposed for multiple extended target tracking. However, the clutter process in the ET‐PHD filter is modelled as Poisson RFS, which is reasonable for only some scenarios in reality. An easily implemented ET‐PHD filter for arbitrary clutter process, has not yet been studied. In this work, another form of the general PHD filter, suitable for arbitrary clutter and target measurement is derived using a probability generating functional (PGFL)‐based RFS framework. The proposed filter is equivalent to the general PHD filter proposed by Clark and Mahler, but it is easily implemented in an arbitrary clutter process because its clutter process is denoted by the probability density function. Then, an arbitrary clutter ET‐PHD (AC‐ET‐PHD) filter is simplified from the general PHD filter derived by us. To reduce the computational complexity of the proposed filter, a variant of the distance partitioning algorithm is put forward. Simulation results show that the AC‐ET‐PHD filter can be applied to the scenarios with the non‐Poisson clutter process, which means that it will be useful for multiple extended targets tracking in a more complicated clutter process. [ABSTRACT FROM AUTHOR]

As the key requirement of the power system, the power transformer's running state of security is directly related to the safety and stability of entire power system. Since condition‐based maintenance for a power transformer cannot directly determine the best maintenance cycle, from a better engineering application perspective, this paper proposes a novel maintenance strategy based on failure probability analysis. First, the power transformer's basic fault probability curve is fitted using the nonlinear least‐squares method. Second, comprehensively considering the long‐term evolution factors and the short‐term sudden factors, the transformer's actual fault probability model is established through amending its basic fault probability model. Third, in accordance with the periodic maintenance experience and the transformer's actual fault probability model, the best maintenance cycle is suggested using the threshold constraint. Finally, the simulation results testify that the proposed maintenance strategy can provide a more accurate maintenance cycle than the existing condition‐based maintenance and can better meet the requirement of engineering applications. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Aim The main aims of this article are to estimate the number of offences that are committed for every one that leads to conviction, and to estimate the probability of an offender being convicted. Method In the Pittsburgh Youth Study, 506 boys were followed up from age 13 to age 24 years, in interviews and criminal records. Self-reports and convictions for serious theft, moderate theft, serious violence and moderate violence were compared. Results On average, 22 offences were self-reported for every conviction. This scaling-up factor increased with age and was the highest for moderate theft and the lowest for serious theft. The probability of a self-reported offender being convicted was 54%. This percentage increased with the frequency and seriousness of offending and was always higher for African American boys than for Caucasian boys. These race differences probably reflected differences in exposure to risk factors. Conclusions More research is needed on scaling-up factors, on frequent and serious offenders who are not convicted, on self-reported non-offenders who are convicted and on why African American boys are more likely than Caucasian boys to be convicted. [ABSTRACT FROM AUTHOR]

The quantum mechanics (QM) and quasiclassical trajectory (QCT) calculations have been carried out for the title reaction with the ground minimal allowed rotational state of CH ( j = 1) on the 1 1A′ potential energy surface. For the reaction probability at total angular momentum J = 0, a similar trend of the QM and QCT calculations is observed, and the QM results are larger than the latter almost in the whole considered energy range (0.1-1.5 eV). The QCT integral cross sections are larger than the QM results with centrifugal sudden approximation, while smaller than those from QM method including Coriolis coupling for collision energies bigger than 0.25 eV. The quantum wave-packet computations show that the Coriolis coupling effects get more and more pronounced with increasing of J. In addition to the scalar properties, the stereodynamical properties, such as the average rotational alignment factor < P2( j′• k)>, the angular distributions P(θr), P(ϕr), P(θr,ϕr), and the polarization-dependent generalized differential cross sections have been explored in detail by QCT approach. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The purpose of the fault detection and diagnosis of stochastic distribution control systems is to use the measured input and the system output probability density functions (PDFs) to obtain the fault information of the system. In this paper, the rational square-root B-spline model is used to represent the dynamics between the output PDF and the input. This is then followed by the novel design of a non-linear neural network observer-based fault diagnosis (FD) algorithm so as to diagnose the fault in the dynamic part of such systems. Convergency analysis is performed for the error dynamic system raised from the fault detection and diagnosis phase using the Lyapunov stability theorem. Finally, based on the FD information, a new faulttolerant control based on proportional integral tracking control scheme is designed to make the post-fault PDF still track the given distribution. A simulated example is given to illustrate the efficiency of the proposed algorithms. [ABSTRACT FROM AUTHOR]

The Stochastic Field Method was originally derived in the field of combustion and firstly applied to a cavitation problem by our group [1]. Randomly distributed variables exist in both combustion and cavitating problems. Calculating strong nonlinear processes using mean values as input, leads to unphysical results. The consideration of the variable's probability density function (PDF) becomes mandatory. The Stochastic Field Method approximates this PDF by samples similar to methods of Lagrangian particles where imaginary particles are introduced to the flow. In contrast to Lagrangian particles methods, these samples are represented by Eulerian fields described by stochastic partial differential equations. This pure Eulerian interpretation makes the method attractive for CFD‐codes: A coupling of an Eulerian and a Lagrangian perspective becomes obsolete which results in efficient computation times ‐ especially in the presence of a vast number of bubbles. In contrast to other Eulerian methods, the calculation of an arbitrary PDF is possible at low computational cost. The representation of samples as fields allows the visualization of PDFs within every computational cell. The first implementation into a commercial CFD‐Code is presented. In addition, industrial examples, like cavitation in an automotive injection nozzle, are shown. [ABSTRACT FROM AUTHOR]

Magnitude modulation (MM) envelope control is an efficient way of reducing the peak-to-average power ratio (PAPR) of single-carrier (SC) signals and improves an SC system's overall power efficiency. However, MM techniques reduce the PAPR at the cost of introducing distortion, highlighting a need to characterise the symbol error rate (SER) performance loss due to MM. This reported work focuses on the M-PSK case. An exact probability density function (PDF) based on the generalised extreme value distribution is proposed to model the statistical distribution of MM factors generated by MM techniques applied to SC constant amplitude constellations. By considering MM distortion as a form of fading, it is shown that this PDF may be used to derive an accurate union bound of the SER of M-PSK transmission on the additive white Gaussian channel channel when using MM envelope control. [ABSTRACT FROM AUTHOR]