We investigate the problem of creating fast evacuation plans for buildings that are modeled as grid polygons, possibly containing exponentially many cells. We study this problem in two contexts: the “confluent” context in which the routes to exits remain fixed over time, and the “non-confluent” context in which routes may change. Confluent evacuation plans are simpler to carry out, as they allo...

We present e cient algorithms for two problems of facility location. In both problems we want to optimize the location of two facilities with respect to n given sites. The rst problem, the continuous version, has no restrictions for facility locations but in the second one, the discrete version, facilities are chosen from a speci ed set of possible locations. We consider the rectilinear metric ...

BACKGROUND Water pipe smoking is increasing in Eastern Mediterranean Region. The objective of this study was to investigate any relationship between water pipe smoking and health-related quality of life in the general population of Bandar Abbas, Iran. METHODS Using a multistage sampling method, a random sample of 1675 individuals aged 15 years and over was studied from June through July 2007....

Pipe network layout optimization is an important and difficult problem in pipe network engineering. Differing from the previously proposed approaches for various optimization formulations, the authors use a methodology for pipe network optimization consisting of network layout optimization coupled with pipe sizing analysis. The methodology is based on a novel heuristic optimization algorithm in...

An analytical investigation and conceptual design of a disk-shaped asymmetric heat pipe is presented in this work. Using the conservative formulations for the steady incompressible vapor and liquid flow for a disk-shaped heat pipe, an in-depth integral analysis is applied. Analytical results for the asymmetric vapor velocity profile, the vapor and liquid pressure distributions, and the vapor te...

BACKGROUND Smoking tobacco preparations in a water pipe (hookah) is widespread in many places of the world and is perceived by many as relatively safe. We investigated biomarkers of toxicant exposure with water pipe compared with cigarette smoking. METHODS We conducted a crossover study to assess daily nicotine and carcinogen exposure with water pipe and cigarette smoking in 13 people who wer...

Article history: Received: 18.09.2013. Received in revised form: 21.03.2014. Accepted: 24.03.2014. Static structural analysis of a pipe during laying is usually performed by use of finite element analysis tools specialized for this purpose. In this paper, Abaqus/CAE, which is general purpose FEA software, was used for a static non-linear structural analysis of a pipe during pipe laying. The pip...

BACKGROUND Water pipe tobacco smoking is spreading globally and is increasingly becoming popular in the United States, particularly among young people. Although many perceive water pipe smoking to be relatively safe, clinical experimental studies indicate significant exposures to tobacco smoke carcinogens following water pipe use. We investigated biomarkers of nicotine intake and carcinogen exp...

In the present study, heat transfer and entropy analysis for flow through a pipe system is considered. The Reynolds number and the pipe wall temperature effects on entropy distribution and total entropy generation in the pipe are investigated. Numerical scheme employing a control volume approach is introduced when solving the governing equations. Steel is selected as pipe material, while water ...