All power systems have some inherent level of flexibility— designed to balance supply and demand at all times. Variability and uncertainty are not new to power systems because loads change over time and in sometimes unpredictable ways, and conventional resources fail unexpectedly. Variable renewable energy supply, however, can make this balance harder to achieve. Both wind and solar generation ...

We present nine 3.6-cm VLBI observations of the optically violent variable (OVV) flat-spectrum radio quasar PKS 0420–014 taken over a period of three years (1989.32– 1992.48); we also show a VLBI map from observations at 43 GHz in 1992.4. We trace jet evolution and variability with individual components. We find superluminal motion with βapp ∼ 2–14c for five jet components. Components ejected m...

Characterisation of the spatial structure of population variables is important for several reasons. Firstly, knowledge of how population subgroups are distributed across spatial scales has direct links to several research areas including analyses of deprivation, residential segregation and health status. For any application concerned with concentrations of members of different groups, spatial s...

This paper uses descriptive statistics and regression analyses to esamine the relationship between exchange rate variability and output volatility in developed countries based on 1961 to 1984 data. The results indicate that a flexible exchange rate system is associated with less, not more, dispersion in output growth across industrialized countries despite a more turbulent global environment. A...

Firms continuously vary the prices of their products in the marketplace. These variations sometimes exhibit consistent patterns, such as higher-priced products having greater price variability. For example, in the grocery industry, more expensive stores tend to have more frequent price changes (Information Resources Inc. 1993). Similarly, with airlines, the lowerpriced, low-frills Southwest Air...

The Scottish aquaculture industry has been expanding steadily for several decades, and has an objective to double production between 2015 and 2030. While the Scottish government supports this aim, concerns about farm impacts have meant that developments are generally opposed at a local scale, where the planning and consent process takes place. In particular, the spread of sea lice and other pat...

The relationship between vegetation, transportation networks, and crime has been under debate. Vegetation has been positively correlated with fear of crime; however, the actual correlation between vegetation and occurrences of crime is uncertain. Transportation networks have also been connected with crime occurrence but their impact on crime tends to vary over different circumstances. By conduc...

BACKGROUND Spatial epidemiology has been aided by advances in geographic information systems, remote sensing, global positioning systems and the development of new statistical methodologies specifically designed for such data. Given the growing popularity of these studies, we sought to review and analyze the types of spatial measurement errors commonly encountered during spatial epidemiological...

abstract soil invertebrate and their spatial pattern are affected strongly by environmental factors. spatial variability of soil properties is one of the most important reasons of the macrofauna variability. this study was conducted to investigate the spatial variability of soil properties and soil macrofauna biomass in the riparian forest landscape of karkhe river. soil macro fauna were sample...