This paper describes a new method and several views for a minimally dependent set of measurements in the power systems observability studies. The minimal measurement sets are important schemes for state estimation analysis. The presented approach is based on a novel observability method named RCD, which does not use an initial measurement set. The total number and each combination of measurements in a search-tree construction are discussed. Owing to the large number of cases, the results are shown for 3-bus and a 6-bus power network.

Linear impulsive fractional differential-algebraic systems (LIFDAS) in a finite dimensional space are studied. We obtain the solution of LIFDAS. Using Gramian matrices, necessary and sufficient conditions for controllability and observability of time varying LIFDAS are established. We acquired the criterion for time-invariant LIFDAS in the form of rank conditions. The results are more generalized than the results that are obtained for various differential-algebraic systems without impulses.

Nowadays, the optimal application of phasor measurement units (PMUs) in power systems is increasing because of their advantages such as the capability for dynamical state estimation and improvements in the speed of control and protection systems. In this paper, a new method is presented using binary integer linear programming for the optimal placement of PMUs to guarantee full observability of a power system. Moreover, the problem of the optimal placement of these units in the case of a single line outage is investigated. In all of the investigations, the effect of zero-injection buses in the power system was considered. The ability of the proposed method in solving any of these problems was demonstrated by applying to the 14-, 30-, 39-, 57- and 118-bus IEEE standard systems, 42-bus transmission network of Esfahan Regional Electric and also two very large-scale systems with 2383 and 2746 buses. The simulation results verified the effective and appropriate performance of the proposed method in comparison with other methods.

The application of machine learning techniques for constructing automated test oracles has been successful in recent years. However, existing machine learning based oracles are characterized by a number of de ciencies when applied to Software systems with low observability, such as embedded Software, cyber-physical systems, multimedia Software programs, and computer games. This paper proposes a new black box approach to construct automated oracles that can be applied to Software systems with low observability. The proposed approach employs an Arti cial Neural Network algorithm that uses input values and corresponding pass/fail outcomes of the program under test as the training set. To evaluate the performance of the proposed approach, extensive experiments were carried out on several benchmarks. The results manifest the applicability of the proposed approach to Software systems with low observability and its higher accuracy than a well-known machine learning based method. This study also assessed the e ect of di erent parameters on the accuracy of the proposed approach.

We discuss the controllability and observability of time-invariant (continuous time) linear systems with interval coefficients using the notion of being full rank of interval matrices. The most important advantage of the proposed attitude is to consider these two essential concepts, that is, control lability and observability, in interval time-invariant linear systems, which, in turn, may play important roles in the analysis of uncertain systems. Some different definitions on to be full rank of matrices have been utilized to propose different views on the controllability and observability of interval linear systems according to different criteria. Finally, in several control-observation processes, the controllability and observability are evaluated based on the given achievements.

Nowadays, phasor measurement units are used in power networks for different purposes, such as Linearization of state estimation equations and speed improvement of controlling and protecting systems. Optimization of position and number of these equipments is considerably important because of their high costs. Effective parameters on position and number of PMUs optimization are: Network topology, zero injection buses and commonly used measurement devices in power networks. In this paper an objective function based on integer linear programming (ILP) is presented to determine the number and optimized position of PMUs, in order to complete observability of power systems. The effect of zero injection buses and prevalent measurement devices on objective function in power networks is evaluated. Simulation results are presented for the IEEE 9, 14, 30, 39, 57 and 118 buses systems. The optimization method is numerically solved using MATLAB Software environment and formation of parameters of objective function in IEEE 14 buses network has been studied.

The Security of Power networks is one of the main focuses of operation utilities and measuring parameters of lines, buses, and other substantial equipment has particular importance for them. Essential role of measuring and control in normal operation of smart grids makes cyber security an important necessity for todays and future power grids. Therefore, as the power network depends on communication systems and information technologies, using phasor measurement units (PMUs) in order to measuring, protection and control become expanded. Reconfiguration of the power network is implemented for several reasons including loss reduction, improving voltage profile, power quality, etc. In this paper power network observability through PMUs which are allocated optimally is analyzed in reconfigured networks in order to investigate the network cyber security. Performance of the proposed method is evaluated in 14-bus and 30-bus IEEE.