There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

The many different techniques for maximum power point tracking of photovoltaic (PV) arrays are discussed. The techniques are taken from the literature dating back to the earliest methods. It is shown that at least 19 distinct methods have been introduced in the literature, with many variations on implementation. This paper should serve as a convenient reference for future work in PV power generation.

/pdf/comparison-of-photovoltaic-array-maximum-power-point-2nci76j6n4.pdf

Comparison of Photovoltaic Array Maximum Power Point Tracking Techniques

1980 Preface * 1999 Preface * 1999 Acknowledgements * Introduction * 1 Circular Logic * 2 Phase Singularities (Screwy Results of Circular Logic) * 3 The Rules of the Ring * 4 Ring Populations * 5 Getting Off the Ring * 6 Attracting Cycles and Isochrons * 7 Measuring the Trajectories of a Circadian Clock * 8 Populations of Attractor Cycle Oscillators * 9 Excitable Kinetics and Excitable Media * 10 The Varieties of Phaseless Experience: In Which the Geometrical Orderliness of Rhythmic Organization Breaks Down in Diverse Ways * 11 The Firefly Machine 12 Energy Metabolism in Cells * 13 The Malonic Acid Reagent ('Sodium Geometrate') * 14 Electrical Rhythmicity and Excitability in Cell Membranes * 15 The Aggregation of Slime Mold Amoebae * 16 Numerical Organizing Centers * 17 Electrical Singular Filaments in the Heart Wall * 18 Pattern Formation in the Fungi * 19 Circadian Rhythms in General * 20 The Circadian Clocks of Insect Eclosion * 21 The Flower of Kalanchoe * 22 The Cell Mitotic Cycle * 23 The Female Cycle * References * Index of Names * Index of Subjects

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/596B270197FE27DE5FABB598B6210622/S0025557200150892a.pdf/div-class-title-span-class-italic-the-geometry-of-biological-time-span-by-a-t-winfree-pp-544-dm68-corrected-second-printing-1990-isbn-3-540-52528-9-springer-div.pdf

The geometry of biological time , by A. T. Winfree. Pp 544. DM68. Corrected Second Printing 1990. ISBN 3-540-52528-9 (Springer)

This ebook is the first authorized digital version of Kernighan and Ritchie's 1988 classic, The C Programming Language (2nd Ed.). One of the best-selling programming books published in the last fifty years, "K&R" has been called everything from the "bible" to "a landmark in computer science" and it has influenced generations of programmers. Available now for all leading ebook platforms, this concise and beautifully written text is a "must-have" reference for every serious programmers digital library.

As modestly described by the authors in the Preface to the First Edition, this "is not an introductory programming manual; it assumes some familiarity with basic programming concepts like variables, assignment statements, loops, and functions. Nonetheless, a novice programmer should be able to read along and pick up the language, although access to a more knowledgeable colleague will help."

The C programming language

Numerical Initial Value Problems in Ordinary Differential Equations

The present trend for commercial telecommunication and scientific satellites is the utilization of standard platform, characterized by a high level of flexibility and reduced nonrecurring costs. One of the areas where flexibility is mandatory is the electrical primary power subsystem, due to the impact on solar array configuration and dimensions and on power conditioning unit. Use of the maximum power point tracker (MPPT) concept allows optimization of the above mentioned subsystem, maximizing the power transfer from the photovoltaic generator. The purpose of the paper is to present a new MPPT approach that allows minimization of the drawback caused by the intrinsic capacitance of the photovoltaic array (generally neglected) giving the possibility of operation with a large degree of freedom, independent from the converter topology and photovoltaic power generator, electrical network and technology.

New approach to photovoltaic arrays maximum power point tracking

A photovoltaic (PV) plant model is presented. It is based on a detailed electrothermal description of the panels forming strings that, in turn, form the power plant. It accounts for environmental working conditions, such as temperature and wind speed, and specific plant configuration, such as plant topology and power losses due to interconnections. The input variables of the model are the ambient temperature, irradiance, and wind speed. The model derives the working temperature of the panel taking into account also the power conversion performed by the panel; the electrical operating point is determined by simulating the actions done by the maximum power point tracker that operates at plant level. This model has been tested using a large database of experimental data from industrial PV plants characterized by power levels ranging from 250 kW to 1 MW. As shown, the model is capable to predict power production when “fed” by forecast irradiance, ambient temperature, and wind speed data.

Model of Photovoltaic Power Plants for Performance Analysis and Production Forecast

In deep-submicrometer layouts, the determination of the signal delay due to interconnects is a main aspect of the design. Usually, on-chip interconnects are modeled by a distributed resistance-capacitance (RC) line. Key aspects of the interconnect modeling are the extraction of parasitic capacitances and the determination of reduced lumped models suited for electrical simulation. This paper addresses both these aspects. The parasitic capacitance extraction problem of layouts is efficiently carried out by means of the floating random walk (FRW) algorithm. It is shown how the employment of the Monte Carlo integration jointly to an extended version of the FRW algorithm allows to directly synthesize an accurate reduced-order RC equivalent net. The new method can deal with very complex geometries in an efficient way and needs neither fracturing of the original layout into subregions nor discretization of interconnects.

Statistical method for the analysis of interconnects delay in submicrometer layouts

Steady state simulation and noise analysis are two essential tools for circuit designers. The algorithms currently available in commonly used simulators are basically limited to the analysis of analog circuits that can be modeled by Lipschitz continuous functions. This is a strong restriction, since current applications are often naturally described by mixed analog-digital models; these models are only piece-wise continuous and Lipschitz condition is not satisfied in the breakpoints. In this paper we propose a method to overcome this limitation by showing how circuits in this class, and, in general, circuits showing discontinuities, can be modeled as hybrid systems. Conventional steady state and noise analysis methods are then extended to this class of circuits. A method to identify the discontinuity points, that, in general, are not known a priori in circuit analysis, is also proposed. With this last addition the method is fully automated and does not require any user intervention.

Steady State Computation and Noise Analysis of Analog Mixed Signal Circuits

Circuit simulation is seen by some people as a well established discipline, where there remains little or no space for improvement. Yet, no steady state and stability analysis methods are available for circuits described by a combination of analog, digital and behavioral parts. Recently, the theory necessary for development of such simulators was proposed and a circuit simulator incorporating these theoretical developments has been presented. It manages analog, digital and behavioral components, while retaining all the classical ?spice-like? features. This was possible by importing some mathematical concepts from the hybrid dynamical systems realm. Such tools represent the interface between the conventional analog world and the more contemporary digital/behavioral one. The reviewed simulation framework is appealing not only for people interested in circuit analysis and design, but for all researches and engineers working in the wider field of system simulation where the analog mixed signal concept is absolutely pervasive.

Angelo Brambilla

Papers

New approach to photovoltaic arrays maximum power point tracking

Model of Photovoltaic Power Plants for Performance Analysis and Production Forecast

Statistical method for the analysis of interconnects delay in submicrometer layouts

Steady State Computation and Noise Analysis of Analog Mixed Signal Circuits

Simulation of Real World Circuits: Extending Conventional Analysis Methods to Circuits Described by Heterogeneous Languages