Sharif Digital Repository

With the outbreak of the coronavirus in countries around the world, governments have decided to impose restrictions and social distancing. Closures of businesses, and hence changes in supply and demand patterns during this period, have deepened concerns among policy makers. In this article, we investigate the change in primary energy consumption in the 20 European countries that have the highest GDP. To this end, 10 different shock scenarios and its limitations are considered. By implementing these shocks into input-output modelling, changes in primary energy consumption are calculated. The results show that according to the best scenario (rapid and complete economy restoration), Russia with... 

Due to the unavailability of accurate data and the limitations of the existing methods, reliable input–output tables (IOTs) may not be available for all the regions in a country. This study proposes a novel approach to estimate the regional input coefficients. It harnesses the capabilities of machine-learning (ML) algorithms to estimate the regional input coefficients of one region based on the IOTs of multiple other regions for which reliable data are available. The application of three ML algorithms is investigated using data from Japan. The results highlight the superior performance of the ML models compared with location quotient models. © 2021 Regional Studies Association  

Due to the unavailability of accurate data and the limitations of the existing methods, reliable input–output tables (IOTs) may not be available for all the regions in a country. This study proposes a novel approach to estimate the regional input coefficients. It harnesses the capabilities of machine-learning (ML) algorithms to estimate the regional input coefficients of one region based on the IOTs of multiple other regions for which reliable data are available. The application of three ML algorithms is investigated using data from Japan. The results highlight the superior performance of the ML models compared with location quotient models. © 2021 Regional Studies Association  

In this paper, we derive Z input/output data refinement rules, including forwards and backwards rules, for the case in which the retrieve schemas are total functions when viewed as relations from the concrete to abstract variables. In practice, the relation between the abstract and concrete variables is often functional. Therefore, the use of the functional input/output refinement rules will reduce the cost and duration of the software development because the proof of the consistency of the abstract and concrete specifications is more easily demonstrated  

The problem of secure communication over multiple-Access Wiretap channel (MAC-WTC) under strong secrecy criterion is investigated. A new technique based on channel output statistics approximation is developed for establishing the strong security over multi-user channels. In particular, this technique shows that how simple wiretap coding results in secure communication under strong secrecy criterion instead of weak secrecy criterion. As a side result of the paper, two results on the output statistics of MAC are provided. Such results can be used to approximate the mutual information between input and output of MAC with respect to a given codebook of arbitrary rate  

With the outbreak of the coronavirus in countries around the world, governments have decided to impose restrictions and social distancing. Closures of businesses, and hence changes in supply and demand patterns during this period, have deepened concerns among policy makers. In this article, we investigate the change in primary energy consumption in the 20 European countries that have the highest GDP. To this end, 10 different shock scenarios and its limitations are considered. By implementing these shocks into input-output modelling, changes in primary energy consumption are calculated. The results show that according to the best scenario (rapid and complete economy restoration), Russia with... 

This paper presents an input/output feedback linearization control strategy for the three-level three-phase neutral-point-clamped rectifier using it's dual Lagrangian modeling, which is obtained based on the superposition law, the load current and The Euler-Lagrange description of the rectifier. The load current can be given in two forms: 1. the load current involving the current of capacitor C1 and 2. The load current involving the current of capacitor C2 Applying the obtained load current to the Euler-Lagrange parameters of the rectifier, two nonlinear models of the system are derived. Also two the power-balance equations between the input and output sides are obtained by considering the... 

In this paper, an attractive and novel algorithm for improving irreducible model identification of continuous time(CT) MIMO systems has been presented. The algorithm is based on least - squares (LS) estimates of Markov parameters (MP) using input output data and residual whitening. By choosing a linear-in-parameters model structure, the estimation becomes linear and asymptotically robust to zero-mean additive disturbances. CT Markov parameters may result in diverging approximations even for stable systems. To remove the existing limitations in the case of systems with low or zero damping, Markov Poisson parameters have been used to lend much flexibility to the estimation model. The MIMO... 

This paper considers the problem of computing the weak visibility polygon (WVP) of any query line segment pq (or WVP(pq)) inside a given simple polygon P. We present an algorithm that preprocesses P and creates a data structure from which WVP(pq) is efficiently reported in an output sensitive manner. Our algorithm needs O(n2log n) time and O(n2) space in the preprocessing phase to report WVP(pq) of any query line segment pq in time O(|WVP(pq)|+log2 n+κlog2 (nκ)), where κ is an input and output sensitive parameter of at most |WVP(pq)|. We improve the preprocessing time and space of current results for this problem [11,6] at the expense of more query time  

We show that in a microfluidic network with low Reynolds numbers, a system can be irreversible due to hysteresis effects. We simulated a network of pipes that was used in a recent experiment. The network consists of one loop connected to input and output pipes. A train of droplets enters the system at a uniform rate, but the droplets may leave the system in a periodic or even a chaotic pattern. The output pattern depends on the time interval between incoming droplets as well as the network geometry. For some parameters, the system is not reversible  

Oscillatory behavior and transfer properties of relay feedback systems with a linear plant including a fractional-order integrator are studied in this paper. An expression for system response in the time domain is obtained by means of short memory principle, Poincare return map, and Mittag-Leffler functions. On the basis of this expression, the frequency of self-excited oscillations is approximated. In addition, the locus of perturbed relay system (LPRS) is derived to analyze the input-output properties of the relay system. The presented analysis is supported by a numerical example. Copyright © 2017 by ASME  

The great surge in the research of community discovery in complex network is going on due to its challenging aspects. Dynamicity and overlapping nature are among the common characteristics of these networks which are the main focus of this paper. In this research, we attempt to approximate the granular human-inspired viewpoints of the networks. This is especially helpful when making decisions with partial knowledge. In line with the principle of granular computing, in which precision is avoided, we define the micro- and macrogranules in two levels of nodes and communities, respectively. The proposed algorithm takes microgranules as input and outputs meaningful communities in rough... 

For processes that repeat the same task an iterative control method can be applied that learns from the previous runs and corrects the tracking error for the next run. Meanwhile, a set membership identification technique is be combined with the regulation part to identify the plant response using the informative input-output data of previous observations. This combination method has been experimentally tested on a radio frequency machine and the results are presented in the paper. © 2019 EUCA  

In general quantum operations, or quantum channels cannot be inverted by physical operations, i.e., by completely positive trace-preserving maps. An arbitrary state passing through a quantum channel loses its fidelity with the input. Given a quantum channel E, we discuss the concept of its quasi-inverse as a completely positive trace-preserving map Eqi which when composed with E increases its average input-output fidelity in an optimal way. The channel Eqi comes as close as possible to the inverse of a quantum channel. We give a complete classification of such maps for qubit channels and provide quite a few illustrative examples. © 2020 American Physical Society  

In this paper, an adaptive fuzzy temperature controller is proposed for a class of continuous stirred tank reactors (CSTRs) based on input-output feedback linearization. Since for control implementation concentrations of all species are needed, based on the observability concept, a fuzzy logic system is used to estimate the concentration dependent terms and other unknown system parameters in the control law, using temperature measurements. It has been shown that the H∞ tracking control performance with a prescribed attenuation level is achieved, by using the proposed controller. Finally the effectiveness of the proposed controller has been demonstrated by applying it to a benchmark chemical... 

A high step-up converter including one active switch is presented in the present work. The introduced structure is a combination of Quadratic boost converter and Zeta converter; therefore, it features low input and output current ripples. The energy of leakage inductor is inherently recovered and the voltage spike on switch is perfectly mitigated. The voltage across diodes and switch is quite lower than the boosted output voltage which can be a prominent issue in high step-up converters. This can lead to employ switches and diodes with low conduction losses causing overall efficiency to increase. The converter function in CCM and DCM are analyzed, and the voltage conversion ratio along with...