Sharif Digital Repository

In order to be more precise to find primary cosmic particles directions, nowadays detectors and data analysis for studying secondary particles in extensive air showers have an ongoing progress and water Cherenkov detector is considered as a secondary particle detector. Our aim in this paper is to optimize the size and the inner surface characteristic of a cylindrical water Cherenkov tank with one PMT. By comparing simulation outputs with experiments results, we show that the diffusing inner surface is more practical than the reflective inner surface and we conclude that the optimum height for a diffusing tank with a diameter of 45cm is 60cm  

In order to monitor auto-correlated processes, many kinds of model-free control charts have been recently proposed based on the methods used in simulation output analysis. However, these control charts always have a restricting assumption that a large volume of observations is available while defects within them are scarce (zero-defect or high-quality processes). In this paper, we develop a new type of model-free unweighted batch means control charts, called grouped batch means (GBM) to monitor autocorrelated processes. In addition to its better performance in some cases, the GBM control chart can be applied not only to high-quality processes but also to all kinds of auto-correlated... 

In this article, a new algorithm for rather expensive simulation problems is presented, which consists of two phases. In the first phase, as a model-based algorithm, the simulation output is used directly in the optimization stage. In the second phase, the simulation model is replaced by a valid metamodel. In addition, a new optimization algorithm is presented. To evaluate the performance of the proposed algorithm, it is applied to the (s,S) inventory problem as well as to five test functions. Numerical results show that the proposed algorithm leads to better solutions with less computational time than the corresponding metamodel-based algorithm. © 2017 Taylor & Francis Group, LLC  

The rapid growth in use of renewable intermittent energy resources, like wind turbines (WTs) and solar panels, in distribution networks has increased the need for having an accurate and efficient method of handling the uncertainties associated with these technologies. In this paper, the unsymmetrical two point estimate method (US2PEM) is used to handle the uncertainties of renewable energy resources. The uncertainty of intermittent generation of WT, photo voltaic cells, and also electric loads, as input variables, are taken into account. The variation of active losses and imported power from the main grid are defined as output variables. The US2PEM is compared to symmetrical two point... 

A novel control method is proposed for single-stage three-phase isolated buck+boost rectifier. The control method is based on the conventional cascade two-loop control structure and is modified to achieve constant instantaneous input power. Input voltages, output voltage, and DC-link inductor current are measured to control the power switches to achieve output voltage regulation as well as input power factor correction. In the proposed method, input currents are controlled such that input power is constant even for unbalanced mains. Thus for balanced mains converter behaves like an ideal rectifier, and for unbalanced mains, low-frequency harmonics of the output voltage are suppressed. The... 

In this paper the problem of chaos control in single mode lateral oscillations of spinning disks is studied. At first, using the harmonic balance method, one of the periodic orbits of system is evaluated. Then proposing a nonlinear feedback strategy a control law is presented for chaos elimination by tracking the mentioned periodic solution. It is shown that although the system is not input-state feedback linearizable, by defining an output signal and using the input-output linearization method, the objective of complete periodic orbit tracking is achieved. The sufficient condition for this purpose is presented, and the performance of proposed method is examined by numerical simulation. ©...