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Integrating-factor-based 2-additive Runge-Kutta methods for advection-reaction-diffusion equationsKroshko, Andrew 30 May 2011 (has links)
There are three distinct processes that are predominant in models of flowing
media with interacting components: advection, reaction, and diffusion.
Collectively, these processes are typically modelled with partial differential
equations (PDEs) known as advection-reaction-diffusion (ARD) equations.<p>
To solve most PDEs in practice, approximation methods known as numerical methods
are used. The method of lines is used to approximate PDEs with systems of
ordinary differential equations (ODEs) by a process known as
semi-discretization. ODEs are more readily analysed and benefit from
well-developed numerical methods and software. Each term of an ODE that
corresponds to one of the processes of an ARD equation benefits from particular
mathematical properties in a numerical method. These properties are often
mutually exclusive for many basic numerical methods.<p>
A limitation to the widespread use of more complex numerical methods is that the
development of the appropriate software to provide comparisons to existing
numerical methods is not straightforward. Scientific and numerical software is
often inflexible, motivating the development of a class of software known as
problem-solving environments (PSEs). Many existing PSEs such as Matlab have
solvers for ODEs and PDEs but lack specific features, beyond a scripting
language, to readily experiment with novel or existing solution methods. The PSE
developed during the course of this thesis solves ODEs known as initial-value
problems, where only the initial state is fully known. The PSE is used to assess
the performance of new numerical methods for ODEs that integrate each term of a
semi-discretized ARD equation. This PSE is part of the PSE pythODE that uses
object-oriented and software-engineering techniques to allow implementations of
many existing and novel solution methods for ODEs with minimal effort spent on
code modification and integration.<p>
The new numerical methods use a commutator-free exponential Runge-Kutta (CFERK)
method to solve the advection term of an ARD equation. A matrix exponential is
used as the exponential function, but CFERK methods can use other numerical
methods that model the flowing medium. The reaction term is solved separately
using an explicit Runge-Kutta method because solving it along with the
diffusion term can result in stepsize restrictions and hence inefficiency. The
diffusion term is solved using a Runge-Kutta-Chebyshev method that takes
advantage of the spatially symmetric nature of the diffusion process to avoid
stepsize restrictions from a property known as stiffness. The resulting methods,
known as Integrating-factor-based 2-additive Runge-Kutta methods, are shown to be able to find higher-accuracy
solutions in less computational time than competing methods for certain
challenging semi-discretized ARD equations. This demonstrates the practical
viability both of using CFERK methods for advection and a 3-splitting in
general.
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Architecture Centric Commenting on ERP System Development - Using SUNON Company as An ExampleYu, Bing-wen 12 January 2004 (has links)
none
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A Study of Software Size Estimation using Function PointWang, Der-Rong 11 July 2003 (has links)
Software size estimation has been long a challenging task over a software development process. This paper presents an approach that uses the function point analysis to estimate program coding and testing effort in a MIS department, which maintains an ERP system with low employee transfer rate. The method first analyzes the historical data using regression analysis, and then builds a software estimation model with elaborated coefficients for related parameters. The estimation model is tested with the remaining set of historical data to evaluate its predict accuracy. It is shown that the size estimation model can be as accurate as about 90% correctness. Thus it is useful not only in company-wide information resource allocation, but also in performance evaluation of software engineers.
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Productivity prediction model based on Bayesian analysis and productivity consoleYun, Seok Jun 29 August 2005 (has links)
Software project management is one of the most critical activities in modern software
development projects. Without realistic and objective management, the software development
process cannot be managed in an effective way. There are three general
problems in project management: effort estimation is not accurate, actual status is
difficult to understand, and projects are often geographically dispersed. Estimating
software development effort is one of the most challenging problems in project
management. Various attempts have been made to solve the problem; so far, however,
it remains a complex problem. The error rate of a renowned effort estimation
model can be higher than 30% of the actual productivity. Therefore, inaccurate estimation
results in poor planning and defies effective control of time and budgets in
project management. In this research, we have built a productivity prediction model
which uses productivity data from an ongoing project to reevaluate the initial productivity
estimate and provides managers a better productivity estimate for project
management. The actual status of the software project is not easy to understand
due to problems inherent in software project attributes. The project attributes are
dispersed across the various CASE (Computer-Aided Software Engineering) tools and
are difficult to measure because they are not hard material like building blocks. In
this research, we have created a productivity console which incorporates an expert
system to measure project attributes objectively and provides graphical charts to
visualize project status. The productivity console uses project attributes gathered
in KB (Knowledge Base) of PAMPA II (Project Attributes Monitoring and Prediction
Associate) that works with CASE tools and collects project attributes from the
databases of the tools. The productivity console and PAMPA II work on a network, so
geographically dispersed projects can be managed via the Internet without difficulty.
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MDP for SymbianJonsson, Erik, Persson, Mikael January 2008 (has links)
<p>The content of this report describes a bachelor thesis performed on commission by Cybercom Sweden West. The report describes techniques, methods and development tools used during the project. The purpose of this project is to demonstrate the usefulness with a new Bluetooth profile called Medical Device Profile (MDP) on the Medica trade fair 14-11-2007. The MDP profile that will be released in turn of the ear 07/08 is primarily intended to be used in medical devices.The demonstration is to be made by building a demonstrator consisting of an application running on a smartphone with Bluetooth abilities. The application will handle the Bluetooth connection between the smartphone and the oximeter, the data encryption and other functionalities and presenting the figures received form the oximeter in a Graphical User Interface (GUI).The final demonstrator consists of a smartphone application programmed in Symbian C++, which communicates with the oximeter using the Bluetooth Serial Port Profile (SPP). The application runs on UIQ 3.0 based smartphones and displays heart rate and %SpO2 (The percentage of oxygen saturation in blood), which the application receives from the oximeter.The original idea was to use the MDP profile by porting Cybercom's C version of the MDP to Symbian OS for the Bluetooth communication, depending on various factors described more in detail inside the report this was not done. The purpose of the project was still reached, even though another profile then MDP was used. This was done by replacing the considered oximeter for an older version which is using the SPP. By using SPP the same result will be demonstrated but with an older technique, and this will achieve the same result on Medica trade fair. The project was demonstrated on Medica with a successful result.</p>
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Software change management processes in the development of embedded software /Mäkäräinen, Minna. January 2000 (has links) (PDF)
Thesis (doctoral)--University of Oulu, 2000. / Includes bibliographical references. Also available on the World Wide Web.
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Measurement based continuous assessment of software engineering processes /Järvinen, Janne. January 2000 (has links) (PDF)
Thesis (doctoral)--University of Oulu, 2000. / Includes bibliographical references. Also available on the World Wide Web.
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System architecture metrics : an evaluation.Shepperd, Martin John. January 1990 (has links)
Thesis (Ph. D.)--Open University. BLDSC no. DX98111.
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To test before or to test after an experimental investigation of the impact of Test Driven Development /Bhadauria, Vikram S. January 2009 (has links)
Thesis (Ph.D.)--University of Texas at Arlington, 2009.
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Formal analysis of component adaptation techniquesKanetkar, Kavita Vijay. January 2002 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: formal analysis; active interfaces; Z notations; EJ. Includes bibliographical references (p. 97-99).
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