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Abstract In the present work two intelligent load frequency controllers have been developed to regulate the power output and system frequency by controlling the speed of the generator with the help of fuel rack position control. The first controller is obtained using fuzzy logic (FL) only, whereas the second one by using a combination of FL, genetic algorithms and neural networks. The aim of the proposed controller(s) is to restore in a very smooth way the frequency to its nominal value in the shortest time possible whenever there is any change in the load demand etc. The action of these controller(s) provides a satisfactory balance between frequency overshoot and transient oscillations with zero steady-state error. The design and performance evaluation of the proposed controller(s) structure are illustrated with the help of case studies applied (without loss of generality) to a typical single-area power system. It is found that the proposed controllers exhibit satisfactory well overall dynamic performance and overcome the possible drawbacks associated with other competing techniques.

Composite indicators have been increasingly recognized as a useful tool for performance monitoring, benchmarking comparisons and public communication in a wide range of fields. The usefulness of a composite indicator depends heavily on the underlying data aggregation scheme where multiple criteria decision analysis (MCDA) is commonly used. A problem in this application is the determination of an appropriate MCDA aggregation method. Of the many criteria for comparing MCDA methods, the Shannon-Spearman measure (SSM) is one that compares alternative MCDA aggregation methods in constructing composite indicators based on the information loss concept. This paper assesses the effectiveness of the SSM using Monte Carlo approach-based uncertain analysis and variance-based sensitivity analysis techniques. It is found that most of the variation in the SSM arises from the uncertainty in choosing an aggregation method. Therefore, the SSM can be considered as an effective measure for comparing MCDA aggregation methods in constructing composite indicators. We also use the SSM to evaluate five MCDA aggregation methods in constructing composite indicators and present the findings.

AbstractThe article aims to bring into discussion architecture as cultural ingredient, and to investigate the current status of the consecrated or of the recently established heritage (patrimony) as well as to ask questions about the contribution that the experiments of professionals may have in the space of the city. If the architecture educates, innovates, launches questions and controversies, it continuously complements the in situ image of the place, city, or, at global level, of the conceptual, technological and innovative developments. Whether it addresses the town-dweller, the user, the tourist or the curious, architecture continually writes new expressions in city space, negotiating with tradition, arguing and reconstructing fragments of urban life. How much is it accepted, pleasant / loved or challenged - or how much it pleases the initial or subsequent demands, are sensitive discussions in the dedicated domain. Regarded at the level of the object or the ensemble, architecture can be a scenographic background for the city or a piece in the set, a point on a route - landmark of urban paths, or simply an unfolded surface which accommodates activities. From level of the area of discussion, architecture is also another space, the one of debates - from the principles in line with the problems of the world for which it strives to find an answer to the philosophical, the local and the ones related to the built application.

This paper demonstrates the capabilities of the Simulink simulation environment for tuning the parameters of Power system stabilizers (PSS), which play a key role in damping the low-frequency oscillations in the electric power systems. First, the theory and algorithms for optimization of the parameters are examined, focusing on the phase compensation (P-Vr) method, which was selected and implemented in Simulink. The different steps of the tuning algorithm are explained, as well as the formulation of the objective function. The theoretically described steps were practically applied to a single-machine system, as well as to the well-known four-machine system of Kundur. The available solvers were also tested and compared in terms of speed and efficiency.

Hydrogen ingress into a metal has been observed at cavitation in distilled water and in 3% NaCl solution at open circuit potential. The measurements of hydrogen permeation rate have been made using an ultrasonic cavitation facility with an attached Devanathan-Stachurski double cell. Increase in vibration amplitude has been associated with the increase in amplitude of electrochemical voltage and current pulses and with the modification of hydrogen permeation rate. Hydrogen behavior within the metal has been affected by the cavitation induced dynamic stresses and metal deformation hardening, ascertained on the basis of the appearance of hydrogen permeation transients at cavitation in comparison with those recorded for the unstressed state. Metal damage has been a resultof associated effects of cavitation and hydrogen.

Developing a low-carbon economy is the only way for countries to achieve sustainable development. Carbon emission reduction policies and low-carbon technology (LCT) innovation play key roles in developing low-carbon economy. Under government reward and punishment regulations, based on the bilateral matching and evolutionary theories, this paper constructs an evolution model consisting of a manufacturer investing LCT and a supplier offering LCT to analyze multi-phase LCT investment strategies. Firstly, the profit optimization model of a green supply chain is constructed from the perspectives of centralized-matching (CM), decentralized-matching (DM), and mismatching (MM), and the spatial information internal evolution law of multi-phase LCT investment is described by the Markov chain. Then, a bilateral matching algorithm is proposed to solve the equilibrium solutions, and the evolution process of the three modes is analyzed by numerical simulation. Finally, based on the product green degree, we analyze the impact of subsidies and taxes on investment-production decisions. Analytical results show that the matching mechanism proposed in this paper can help supply chain firms to obtain stable matching and has a significant effect on the realization of "triple wins" of society, economy, and environment. The investment utility of CM is higher than that of DM and MM. Manufacturers are inclined to adopt LCT, and the investment level tends to be stable over time. Government reward and punishment regulations are helpful to motivate supply chain firms to invest in LCT, and the synergistic effect of subsidies and taxes is better than that of a single policy.