In this paper, the energy efficiency of airlines has been studied with number of employees, capital stock and tons of aviation kerosene as the inputs and Revenue Ton Kilometers, Revenue Passenger Kilometers, total business income and CO2 emissions decrease index as the outputs. A new model,...

In this paper, transportation carbon efficiency is redefined, and its inputs and outputs are obtained from a literature review. Carbon, capital and labor are selected as the inputs, and passenger turnover volume and freight turnover volume are defined as the outputs. A new model, a virtual...

In many remote areas, expensive fossil fuels such as diesel are used to meet local electricity demand. However, their environmental impact is significant. Consequently, some of these areas have started to use hybrid systems that combine renewable energy sources and fossil fuel generation, such...

During the last decade, the development of tidal current industries has experienced a rapid growth. Many devices are being prototyped. For various purposes, investors, industries, government and academics are looking to identify the best device in terms of of cost of energy and performance....

Three-dimensional effects in studying a vertical axis tidal current turbine are modeled using a newly developed vortex method. The effects on predicting power output and wake trajectory are analyzed in particular. The numerical results suggest that three-dimensional effects are not significant...