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Two basic types of low voltage (LV) distribution exist in practice. The systems based on the European approach have long LV feeders whose sizing requires more careful design consideration than systems based on North American practice with shorter LV feeders. The most important criterion in conductor sizing is the correct estimation of the design loads. This paper describes the development and application of a probabilistic design method based on the Beta probability density function (pdf). The paper investigates an approximate approach for estimating load parameters in countries where a large load database is not available. This approach estimates the Beta parameters from the group after-diversity-maximum-demand (ADMD) for the customers. Index Terms--Load modeling, low-voltage (LV) distribution, probabilistic methods.

This paper presents a practical thermal loading guide for distribution transformers feeding residential customers. Extensive load research data were used to estimate the thermal response of a 'standard IEC distribution transformer.' A strong relationship between the parameters of a load modeled by load current as a function of time and the hotspot temperature was found. Using this type of load model, a method was developed for estimating the hotspot temperature of a transformer for customers from different load classes. A method was derived to translate the thermal response of a standard IEC distribution transformer to any practical transformer. Index Terms--Load modeling, load research, transformer management.

A probabilistic model for residential loads is proposed in this paper. The model differs from other similar models in that it uses a beta probability distribution function (beta pdf) to describe the load uncertainty. It further models the load parameter uncertainty as a bivariate distribution of load current means and standard deviations. By separating the probabilistic load uncertainty and the load parameter uncertainty, the model becomes very useful for the analysis of distribution systems where primarily residential consumers are connected, e.g., electrification projects. The model was tested using a Monte Carlo-type simulation and the results are sufficiently accurate for practical design purposes. Index Terms--Load modeling, power distribution, probability.

The article offers the author's insights on how he and his partner Margaret Nahas have accepted humanism in their lives after they deemed the creation of religion as ignorance of their time.

An essay is presented on the different interpretation of secular humanism from the readers in the U.S. The readers have defined secular humanism as truth, atheism, and evangelistic. One reader believes that secular humanism is similar to atheism and consists of naturalism, ethics, and neo-Darwinian.

Presents views from garden experts on why Japanese gardens are not mainstream topics. Views of Reiner and Gesine Jochems on misleading information about Japanese gardens; Remarks from James T. Hanselman, a garden builder in Manheim, Pennsylvania, on the reasons for the lack of familiarity with Japanese gardens; Statement issued by Mike Oshita, a Japanese garden builder, on the problems with Japanese gardens.

Presents a letter to the editor in response to the editorial "The Immortality of War Against Iraq," in the summer 2003 issue of the journal "Free Inquiry."

Several letters to the editor are presented in response to the article "A Better Name for Us" by Glade Ross in the February-March 2015 issue.