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

Cable ampacity - A Finnish perspective

The significance of the continuous electric power service is getting higher and higher. Countries are developing policies to strengthen their electric power system infrastructure to sustain an acceptable level of supply security. The European electric power policies are guided by the climate and energy goals of the European Union. Climate change related extreme weather events pose a great threat against the power reliability. In terms of natural disasters and their impacts on electricity, Finland is among one of the most affected countries in Europe. This paper presents a detailed electric power reliability analysis for Finnish power system. The increasing influence of natural disasters on supply security is highlighted. The future plans of the Finnish authorities to further harden the power infrastructure and the policy changes to push the network operators to increase the customer satisfaction are also mentioned.

Climate change concerns and finnish electric power supply security performance

It is important to forecast the wind speed range for managing the operation of wind turbines (WTs). Since the electrical power generated by WTs is highly dependent on the uncertain inherent of atmosphere meteorology, improving the accuracy of wind speed range forecasting models leads to the improvement of wind generation prediction. For the sake of uncertainties, it is very challenging to develop an effective and practical model to achieve accurate wind speed range forecasting in large forecasting horizons. This paper presents a novel hybrid classifier based on extended-classifier system with real input (XCSR) and an adaptive neuro-fuzzy inference system (ANFIS), for classification of the wind speed range. It should be mentioned that by employing a cooperative fuzzy classifier system (XCSR–ANFIS), the accuracy and number of the rules that XCSR system must be learned during the training process in the proposed model will be higher and fewer than the XCSR model, respectively. Finally, the comparison of obtained results by implementing the proposed model with other methods for long and short horizons confirms the desirable performance of the proposed model.

A Novel Cooperative Fuzzy Classifier for Predicting the Permissible Wind Speed Range in Wind Farms

Partial discharge (PD) measurements can be regarded as an effective and reliable tool for on-line condition monitoring and asset management of high voltage (HV) apparatus. Recently, a novel application is observed in the monitoring of falling trees on covered-conductor (CC) overhead distribution lines. In this paper, Rogowski and Pearson coils are used as sensors to detect PDs for this specific application. These sensors are non-intrusive and superior to the conventional PD detecting methods. In the next stage of future developments, the wired sensor will be converted into a wireless one. The challenges faced while implementing future wireless technology are also described here. In future, the wireless sensors will be integrated into distribution management system (DMS) to detect and localize the falling trees. The proposed intelligent fault diagnosis system will improve the safety of CC lines and make them more attractive to utilities due to reduced maintenance costs and visual inspection work. In addition, the reliability of the distribution system will improve which is one of the significant characteristics of the future smart distribution networks.

Matti Lehtonen

Papers

Cable ampacity - A Finnish perspective

Climate change concerns and finnish electric power supply security performance

A Novel Cooperative Fuzzy Classifier for Predicting the Permissible Wind Speed Range in Wind Farms

Intelligent fault diagnosis for on-line condition monitoring in smart distribution networks

Simulation Performance of Induced Voltages on Power Lines due to Lightning Discharges to nearby Tree