The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Performance aspects of a Lagrangian relaxation based heuristic for solving large 0–1 integer linear programs are discussed. In particular, we look at its application to airline and railway crew scheduling problems. We present a scalable parallelization of the original algorithm used in production at Carmen Systems AB, Göteborg, Sweden, based on distributing the variables and a new sequential active set strategy...
We have investigated algorithms that are particularly suited for the parallel MD simulations of synthetic polymers. These algorithms distribute the atoms of the polymer among the processors. Dynamic non-bonded interactions, which are the difficult part of an MD simulation, are realised with the help of a special coarse-grained representation of the chain structure. We have devised and compared a master...
Colarado (an acronym for collision avoidance radar able to distinguish obstacles) is a system for use in the control of autonomously driven vehicles, having static radar antennas. By combining the echos, resulting from 2 continuously emitting transmitters and 3 receivers, it is possible to compute the locations of obstacles in 3 dimensions. The main problem is to separate the real obstacles from ghosts...
To use benchmarks or to use real database traces (for the simulation of high performance distributed transaction processing), that is the question. Whether it is preferable to deal with special real workload, or to ignore the rich diversity observable with real measurements by restricting oneself to standardized benchmarks. We demonstrate how the evaluation and comparison of different load balancing...
This paper presents the results of computer simulation obtained with two modifications of the Penna bit-string model of biological ageing. Extinction of population may be caused by number of reasons, overhunting or too many harmful mutations inherited by offsprings among them. In this work we concentrate on population growth dynamics and their age distribution characteristics, such as number of mutations...
The National Aerospace Laboratory NLR is the central aerospace research and development organization in the Netherlands, and is actively involved in international simulation projects. In the HPCN project SIMULTAAN, NLR developes a generic scenario management tool named SMARTFED for real-time monitoring and control of networked simulations. The scenario management tool also offers functionalities to...
The primary mission of the EU-funded OPERA project is the training of operators in the area of chemical industry by means of simulation applications that run in a cost-effective standard LAN environment. As a second goal, OPERA also aims at achieving great flexibility to ease changes in the released simulator. To achieve its primary goal, OPERA had to solve the problem of real-time combined with the...
This paper presents the SEEDS simulation environment for the evaluation of distributed traffic control systems. Starting with an overview of the general simulator architecture, performance measurements of the simulation environment carried out with a prototype for airport ground-traffic simulation are described. The main aspects of the performance analysis are the attained application performance...
With the fast development of internet, the multicasting applications (such as Distant Learning) have become more and more important. Since multicasting multimedia information over the wired links might generate heavy traffic streams to cause congestion, the utilization of internet will be reduced dramatically. The satellite with broadcasting capability and high bandwidth could provide an alternate...
As part of a detailed project investigating racing car wheel aerodynamics, a CAD/CFD (Computer Aided Design—Computational Fluid Dynamics) interface has been used to enable CFD numerical flow visualisation for a generic racing car geometry. The interface was developed and improved through assessment and integration of industrial and baseline CAD formats with the requirements of an in-house state-of-the-art...
Rolling bearing simulations are very computationally intensive and need to utilize the potential of parallel computing. The load distribution over the processors in a rolling bearing simulation is very dynamic. In this paper we present the Adaptive Scheduling Strategy Optimizer (ASSO) for scheduling parallel simulations. The result of this is that the application can automatically select a...
This paper presents the parallelization of a pattern simulation algorithm for Imaging Interferometric Lithography (IIL), a Very Large Scale Integration (VLSI) process technology for producing sub-micron features. The approach uses Message Passing Interface (MPI) libraries [1]. We also discuss some modifications to the basic parallel implementation that will result in efficient memory utilization and...
The Swedish Meterological and Hydrological Institute (SMHI) makes daily forescasts of temperature, salinity, water level, and ice conditions in the Baltic Sea. These forecasts are based on data from a High Resolution Operational Model for the Baltic (HIROMB). This application has been parallelized and ported from a CRAY C90 to a CRAY T3E. Our parallelization strategy is based on a subdivision...
The science and technology agency has begun an “Earth Simulator” project from the fiscal year of 1997, which enables the forecast of various earth phenomena through the simulation of virtual earth placed in a supercomputer. The “GeoFEM” is a parallel finite element software to be run on the “Earth Simulator” to solve problems involving the solid earth and is being developed at RIST. This project is...
The aim of the human neuroscanning project is to build an atlas of the human brain, based on a variety of image modalities in particular histological sections of a prepared brain. Reconstructing essential information out of deformed images is a key problem. We describe a method to correct elastic deformations. Since the method is computational expensive a parallel implementation is presented. The...
Modern scientific computing involves organizing, moving, visualizing, and analyzing massive amounts of data from around the world, as well as employing large-scale computation. The distributed systems that solve large-scale problems will always involve aggregating and scheduling many resources. Data must be located and staged, cache and network capacity must be available at the same time as computing...
The objective of the 3D Heartview methodology was to demonstrate the benefits of HPC technology in improving the diagnostic and clinical procedures of heart diseases. It enables an online 3D modeling of the heart structures based on 2D X-ray angiographic sequences acquired under routine clinical conditions, thus offering medical added value in the areas of operation planning, wall motion study and...
Accurate diagnosis and therapeutic evaluation of coronary dysfunction is possible by tri-dimensional (3D) visualization of Coronary arteries. Reconstruction based on bi-dimensional (2D) images can be presented as a discrete optimization problem. A blind search cannot be applied, instead a Branch-and-Bound algorithm is used to explore the state space and give an intermediate result. The heuristic information...
The efficient implementation of a diffraction tomography method for medical imaging is addressed within the framework of High Performance Computing (HPC) environment. A non-linear optimization method for the solution of the inverse scattering problem is implemented on a shared memory model computer. Linear speed-up and significant reduction in the total execution time is achieved when the program...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.