State of the Art and Future Trends in Grid Codes Applicable to Isolated Electrical Systems

Isolated electrical systems lack electrical interconnection to other networks and are usually placed in geographically isolated areas—mainly islands or locations in developing countries. Until recently, only diesel generators were able to assure a safe and reliable supply in exchange for very high costs for fuel transportation and system operation. Transmission system operators (TSOs) are increasingly seeking to replace traditional energy models based on large groups of conventional generation units with mixed solutions where diesel groups are held as backup generation and important advantages are provided by renewable energy sources. The grid codes determine the technical requirements to be fulfilled by the generators connected in any electrical network, but regulations applied to isolated grids are more demanding. In technical literature it is rather easy to find and compare grid codes for interconnected electrical systems. However, the existing literature is incomplete and sparse regarding isolated grids. This paper aims to review the current state of isolated systems and grid codes applicable to them, specifying points of comparison and defining the guidelines to be followed by the upcoming regulations.

State of the Art and Future Trends in Grid Codes Applicable to Isolated Electrical Systems

Electrical power systems are changing their traditional structure, which was based on a little number of large generating power plants placed at great distances from loads by new models that tend to split the big production nodes in many smaller ones. The set of small groups which are located close to consumers and provide safe and quality energy is called distributed generation (DG). The proximity of the sources to the loads reduces losses associated with transportation and increases overall system efficiency. DG also favors the inclusion of renewable energy sources in isolated electrical systems or remote microgrids, because they can be installed where the natural resource is located. In both cases, as weak grids unable to get help from other nearby networks, it is essential to ensure appropriate behavior of DG sources to guarantee power system safety and stability. The grid codes sets out the technical requirements to be fulfilled for the sources connected in these electrical networks. In technical literature it is rather easy to find and compare grid codes for interconnected electrical systems. However, the existing literature is incomplete and sparse regarding isolated electrical systems and this happens due to the difficulties inherent in the pursuit of codes. Some countries have developed their own legislation only for their island territory (as Spain or France), others apply the same set of rules as in mainland, another group of island countries have elaborated a complete grid code for all generating sources and some others lack specific regulation. This paper aims to make a complete review of the state of the art in grid codes applicable to isolated systems, setting the comparison between them and defining the guidelines predictably followed by the upcoming regulations in these particular systems.

Our Lady of Guadalupe : contemporary explorations of personal and cultural identity

Since it first appeared, the image of Our Lady of Guadalupe has remained relatively unchanged. In the last thirty-five years, however, this has been changing. Artists are creating new variations of the icon to represent and express their reinterpretations. In some of these more contemporary images, the figure of Guadalupe has changed dramatically, but still retains enough traditional elements to be easily recognizable. Some of these images have been received with mixed results and have even sparked major controversy. These new, and sometimes controversial depictions of Guadalupe, specifically those created by Ester Hernández, Yolanda M. López and Alma López, will be explored here. Although each artist has her own individual motivations and intentions, all of the images presented here explore personal and cultural identity, as well as seek in some way to honor ordinary, human women through the sacred iconography of Our Lady of Guadalupe.

Graveyards to Glamour : Development of Sexualized Angel Imagery in American Art and Advertising

Images of female angels in American art and advertisements have been sexualized in the late twentieth and early twenty-­‐first centuries. Companies such as Victoria’s Secret have appropriated the image of female angels, which first appeared at the beginning of the nineteenth century, and clothed them in lingerie in order to sell a product. This Masters Research Paper explores the evolution of female angelic imagery in the United States in order to understand how and when the image of angels began to be sexualized and used in advertising. Angels in art have been studied extensively; however, there has been no work done which examines how the angels in art and advertising have been sexualized. Nor has any work been done to map the evolution of female angelic imagery in American art. This Masters Research Paper will fill that gap in scholarship.

Blurring the lines : how Japanese American internment camps re-defined art and religion's relationship

After the Japanese bombed Pearl Harbor during WWII, anyone of Japanese descent living on the West Coast was placed in internment camps scattered throughout the country. Life inside the camps included many different activities to make life as normal as possible. This study will focus on two intersecting day-to-day activities in particular, the practice of religion within the camps, as well as the creation of art. Art created in the camps was influenced by multiple religious traditions. An analysis of artworks created by professional and amateur artists, interviews and an examination of existing scholarship demonstrates that internment camps created a unique environment for the creation of art. The values of internees reflected the seamless coexistence of Christianity, Buddhism and Shinto in internment camp art.

Graham's American monthly magazine of literature, art, and fashion.

Editors: Jan. 1841- G. R. Graham (with E. A. Poe, Jan. 1841-May 1842; C. J. Peterson, Mrs. Ann S. Stephens, 1842; R. W. Griswold, July 1842-June 1843; R. T. Conrad, Jan.-June 1848: J. R. Chandler, J. B. Taylor, Oct. 1848-Dec. 1849).

Primitive culture: researches into the development of mythology, philosophy, religion, art, and custom,

Mode of access: Internet.

The calendar of the Anglican Church illustrated : with brief accounts of the saints who have churches dedicated in their names, or whose images are most frequently met with in England : the early christian and medieval symbols : and an index of emblems.

Calf, rebacked.

Modern chromatics, with applications to art and industry.

Series title also at head of t.-p.

Art and play therapy.

Mode of access: Internet.