Safety and failure in gas pipelines are very important in gas and petroleum industry. For this reason, it is important to study the effect of different parameters in order to reach the maximum safety in design and application. In this paper, a three dimensional finite element analysis is carried out to study the effect of crack length, crack depth, crack position, internal pressure and pipe thi...

In pipeline-riser systems, pressure fluctuations which result from the formation of large liquid slugs and gas surges due to operational changes or low mass flow rate from production wells and the profile of pipeline-riser systems often lead to trips at the inlet of the separator; and thereby, the problem causes a a loss of the production.In this study, on a sample deep-water oil field off the ...

following the collapse of the soviet :union: and the discovery of gas and oil in central asia and caucasia, it faced complex interests in the international political economy. these problems were mainly rooted in developing plans of the countries for increasing their influence in the area and also in russia's connections with the iranian and turkish governments in the region. this paper inv...

introduction: today, with development of various industries, the adverse events originated from explosion and emission of toxic and chemical substances have increased. these events may cause serious environmental problems that threaten human health and safety. therefore, knowledge about the risk of toxic substances from industrial facilities is essential. although, chlorine is extensively utili...

An Ant Colony Optimization (ACO) algorithm is proposed for optimal tree-structured natural gas distribution network. Design of pipelines, facilities, and equipment systems are necessary tasks to configure an optimal natural gas network. A mixed integer programming model is formulated to minimize the total cost in the network. The aim is to optimize pipe diameter sizes so that the location-alloc...

Following their early domestication, broomcorn millet and rice (in East Asia) wheat barley South-west were subsequently adopted across Eurasia during the Bronze Age/early historic period. The precise timing dispersal routes for this trans-Eurasian exchange, however, remain unclear. Here, authors present archaeobotanical evidence from sites on Caspian Sea's southern coast, demonstrating that rea...

In this paper, a qualitative and a quantitative risk assessment methods for urban natural gas pipeline network are proposed. The qualitative method is comprised of an index system, which includes a causation index, an inherent risk index, a consequence index and their corresponding weights. The quantitative method consists of a probability assessment, a consequences analysis and a risk evaluati...

As part of the U.S. EPA’s Lake Michigan Mass Balance Study, a predictive model for gas-phase persistent organic compounds over Lake Michigan has been constructed. Using air temperature, wind direction and atmospheric PCB concentration collected around and over the lake, the model predicts the concentration of PCB congeners (~100) and trans-nonachlor over the lake and gas exchange fluxes. The mo...

Thousands of Caspian seals (Phoca caspica) died in the Caspian Sea from April to August 2000. Lesions characteristic of morbillivirus infection were found in tissue specimens from dead seals. Canine distemper virus infection was identified by serologic examination, reverse transcriptase- polymerase chain reaction, and sequencing of selected P gene fragments. These results implicate canine diste...