Direct numerical simulation of three-dimensional (3D) viscous flow in a wavy pipe is performed using the lattice Boltzmann approach, to study 3D flow features in a curved pipe with nonuniform curvature. We first validate the lattice Boltzmann approach by simulating a transient flow in a straight pipe. In a wavy pipe, it is shown that the pressure gradient necessary to drive the flow depends mor...

BACKGROUND Water pipe is a traditional method of tobacco use, which is epidemically spreading throughout Europe. There are scarce data about the use of water pipe and its relation to other addictive behaviors among young adults in Western countries. OBJECTIVES It was our aim to identify the sociodemographic characteristics of water pipe users in Switzerland and to describe concurrent cigarett...

In this paper, we present an algorithm, called selforganization assisted placement (SOAP), for circuit placement in arbitrarily shaped regions, including two-dimensional rectilinear regions, nonplanar surfaces of three-dimensional objects, and three-dimensional volumes. SOAP is based on a learning algorithm for neural networks proposed by Kohonen [l], called self-organization, which adjusts the...

Given a set P of terminals in the plane and a partition of P into k subsets P1, . . . , Pk, a two-level rectilinear Steiner tree consists of a rectilinear Steiner tree Ti connecting the terminals in each set Pi (i = 1, . . . , k) and a top-level tree Ttop connecting the trees T1, . . . , Tk. The goal is to minimize the total length of all trees. This problem arises naturally in the design of lo...

In part II of this group of papers, the control of the gait of a biped robot during rectilinear walk was considered. The modeling approach and simulation, using Kane’s method with implementation leveraged by Autolev, a symbolic computational environment that is complementary, was discussed in part I. Performing turns during the walk is technically more complex than the rectilinear case and dese...

A rectilinear Steiner arborescence connects points in the Euclidean plane’s first quadrant and the origin with directed rectilinear edges from the origin up and to the right. The search for arborescences of minimum total length is NP-hard and finds applications in VLSI design. A greedy heuristic for this problem often returns near-optimum arborescences. Three genetic algorithms encode candidate...

The thermodynamic properties of fluids can be predicted using the global equations of state. Among these thermodynamic properties of fluids, we choose the densities of the liquid and vapor phases. This paper considers the application of the crossover model to the vapor-liquid rectilinear diameter of sulfurhexafluoride. We also present a comparison of the crossover model equation with ...

This paper deals with the performance of a heat pipe solar collector. The solar collector consisted of an interconnected heat pipe so as to reduce the production cost by using an interconnected heat pipe because all the heat pipes can be evacuated, sealed and tested at once. Performance of a prototype of the heat pipe solar collector was experimentally examined, and the results were compared wi...

Miniature heat pipes are considered to be an innovative solution able to dissipate high heat with low working fluid fill charge, provide automatic temperature control, and operate with minimum energy consumption and low noise levels. A theoretical analysis on heat pipe thermal performance using Deionized water or n-pentane as the working fluid has been carried out. Analysis on the maximum heat ...

The goal of this study is to improve the thermal characteristics of high power LED (light-emitting diode) package using a flat heat pipe (FHP). The heat-release characteristics of high power LED package are analyzed and a novel flat heat pipe (FHP) cooling device for high power LED is developed. The thermal capabilities, including startup performance, temperature uniformity and thermal resistan...