Considering the high costs of the implementation and maintenance of gas distribution networks in urban areas, optimal design of such networks is vital. Today, urban gas networks are implemented within a tree structure. These networks receive gas from City Gate Stations (CGS) and deliver it to the consumers. This study presents a comprehensive model based on Mixed Integer Nonlinear Programming (...

In this paper we address the new lossy coding method for digital transmission or storage of binary images using hierachical decomposition based on the vector quantization. Binary(white-and-black) images , especially engineering drawings and weather maps, are containing a lot of blank spaces in the entire image. From this aspect, the proposed method are employed two popular compression thechniqu...

Mechanical counter-pressure (MCP) space suits have the potential to improve the mobility of astronauts as they conduct planetary exploration activities. MCP suits differ from traditional gas-pressurized space suits by applying surface pressure to the wearer using tight-fitting materials rather than pressurized gas, and represent a fundamental change in space suit design. However, the underlying...

Repeaters are widely used to combat the quadratic delay of long on-chip wires. A conventional repeater is a CMOS inverter placed periodically along the long wire. This design has two drawbacks. The wire must have an even number of repeaters to preserve signal polarity. This forces the designer to sometimes use a suboptimal number of repeaters. It is also awkward when a wire branches because rep...

Noise is an audible acoustic energy that adversely affects the health, physiological and psychological well being of the individuals or populations. One of the major pollutants from gas flaring is the noise emanating from gas flaring stations in the Niger – Delta area of Nigeria. Noise dispersion produces many adverse effects on man and animals. Experimental analysis of noise dispersion and wea...

Liquefied petroleum gas (LPG) is an important urban gas source in China. Before supplied to customers by pipeline supply systems, LPG is stored in tanks in LPG vaporization stations. Designers usually decide the number and the size of storage tanks by their experience during constructions of vaporization stations. These decisions are usually not best and most economical. To solve the problem, a...

Owing to environmentally-destructive impact of aromatic hydrocarbons, such as benzene, benzene ethyl, toluene, and xylenes or BTEXs, these materials are classified as hazardous pollutants in the air. This study studies cancer and non-cancer risk in District 12 of Tehran Municipality, through these components for two groups of employees or storekeepers and gas station customers. By measuring pol...

Owing to environmentally-destructive impact of aromatic hydrocarbons, such as benzene, benzene ethyl, toluene, and xylenes or BTEXs, these materials are classified as hazardous pollutants in the air. This study studies cancer and non-cancer risk in District 12 of Tehran Municipality, through these components for two groups of employees or storekeepers and gas station customers. By measuring pol...

We apply a semi-classical approach of handling waves as quasiparticle gas in a slowly varying flow – analogous to ray tracing – to calculate the Alfvén wave transmission parameters, the resulting cross-helicity of the waves and the scatteringcentre compression ratio, for cases where the shock thickness is large enough for the turbulent waves in the plasma to see the transition of the background...