I argue that opposite arrows of time, while being logically possible, cannot realistically be assumed to exist during one and the same epoch of this universe.

PEM (Proton Exchange Membrane) fuel cells show characteristics of high power density, low operating temperature and fast start-up capability, which make them potentially suitable to replace conventional power sources (e.g. internal combustion engines) as Auxiliary Power Units (APU) for on-board applications. This paper presents a methodology for a preliminary investigation on either sizing and ...

Biodiesel consisting principally of monounsaturated fatty acid methyl esters (FAME) has been reported to have the optimal balance between cold flow properties and oxidative stability, therefore producing a superior fuel. In addition, treating biodiesel with antioxidants such as selenium (Se) also increases oxidative stability. Fuel properties including acid value (AV), cloud point (CP), iodine ...

Homogeneous charge compression ignition (HCCI) seems to be the most promising solution for gasoline engines in the light of future emissions regulations. This novel combustion technique allows for significant reduction of fuel consumption and engine-out NOX emissions at low and medium engine load/speed conditions. High heat release rate enables realization of the Otto cycle close to ideal, incr...

§10.1. Number Fields and Field Extensions One of the classic non-constructability problems is that of trisecting an angle. Ruler and compass constructions exist for certain angles, such as 60, and constructions exist that approximately trisect any angle, but there are none that exactly trisect any angle. This is not an open question, waiting for some brilliant mathematician to solve it. It is ...

In recent years, great efforts have been made to reduce greenhouse gas emissions by vehicles. Petroleum products produces greenhouse gas emissions, therefore reducing the use of these products can make a major contribution to reducing pollution. The Fleet Size and Mix Vehicle Routing Problem is one of the most widely used routing branches. In this problem, there are vehicle with different capac...