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 DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

计量经济分析 = Econometric analysis

This chapter discusses leading problems linked to energy that the world is now confronting and to propose some ideas concerning possible solutions. Oil deserves special attention among all energy sources. Since the beginning of 1981, it has merely been continuing and enhancing the downward movement in consumption and prices caused by excessive rises, especially for light crudes such as those from Africa, and the slowing down of worldwide economic growth. Densely-populated oil-producing countries need to produce to live, to pay for their food and their equipment. If the economic growth of the industrialized countries were to be 4%, even if investment in the rational use of energy were pushed to the limit and the development of nonpetroleum energy sources were also pursued actively, it would be extremely difficult to prevent a sharp rise in prices. It is evident that it is absolutely necessary to pursue actively the development of coal, natural gas, and nuclear power if a physical shortage of energy is not to block economic growth.

World energy outlook

Introduction to stochastic programming

Investigation of wave propagation characteristics for high frequency pulses is an important aspect for the partial discharge (PD) diagnostics in medium voltage cables. Precision in determining the electromagnetic wave propagation velocity in the cables determines the accuracy of developing cable model and localization of partial discharge initiation site. It has been observed that commonly used time domain reflectometry (TDR) and time difference of arrival (TDA) methods pose certain limitations while finding out the propagation velocity of the cables. This can cause serious inaccuracy during localization of PD faults. This paper presents an alternative quarter wave length (QWL) method in frequency domain to measure the propagation velocity. It is based on transmission line model of the cables and eliminates the practical limitations of TDR and TDA techniques. The comparative assessment of these methods is presented based on experimental measurements. The comparison asserts the improved performance of proposed technique. This improved technique can be used to enhance the diagnostics capability for power networks.

An improved technique to determine the wave propagation velocity of medium voltage cables for PD diagnostics

A novel state estimation model for distribution systems

Eddy losses calculation in transformer windings using FEM

Designing a new procedure for reward and penalty scheme in performance‐based regulation of electricity distribution companies

This paper proposes and investigates a framework for day-ahead hour-by-hour thermal state forecasting of distribution network components. The method takes into consideration the uncertainty brought about by distributed generation and load demand forecasting. Potential risks are evaluated so that contingency measures can be planned with a clear knowledge of tolerance to temporary overloading scenarios.

Matti Lehtonen

Papers

An improved technique to determine the wave propagation velocity of medium voltage cables for PD diagnostics

A novel state estimation model for distribution systems

Eddy losses calculation in transformer windings using FEM

Designing a new procedure for reward and penalty scheme in performance‐based regulation of electricity distribution companies

Dynamic thermal state forecasting of distribution network components: For enhanced active distribution network capacity