<p>A significant part of the software development effort is spent on detecting deviations between software implementations and specifications, and subsequently locating the sources of such errors. This thesis illustrates that is possible to identify a significant number of errors during static analysis of declarative object-oriented equation-based modeling languages that are typically used for system modeling and simulation. Detecting anomalies in the source code without actually solving the underlying system of equations provides a significant advantage: a modeling error can be corrected before trying to get the model compiled or embarking on a computationally expensive symbolic or numerical solution process. The overall objective of this work is to demonstrate that debugging based on static analysis techniques can considerably improve the error location and error correcting process when modeling with equation-based languages.</p><p>A new method is proposed for debugging of over- and under-constrained systems of equations. The improved approach described in this thesis is to perform the debugging process on the flattened intermediate form of the source code and to use filtering criteria generated from program annotations and from the translation rules. Each time when an error is detected in the intermediate code and the error fixing solution is elaborated, the debugger queries for the original source code before presenting any information to the user. In this way, the user is exposed to the original language source code and not burdened with additional information from the translation process or required to inspect the intermediate code.</p><p>We present the design and implementation of debugging kernel prototypes, tightly integrated with the core of the optimizer module of a Modelica compiler, including details of the novel framework required for automatic debugging of equation-based languages.</p><p>This thesis establishes that structural static analysis performed on the underlying system of equations from object-oriented mathematical models can effectively be used to statically debug real Modelica programs. Most of our conclusions developed in this thesis are also valid for other equation-based modeling languages.</p> / Report code: LiU-Tek-Lic-2002:37.

When it comes to the production and reception of texts, most linguists will readily agree that writers as well as readers constitute and follow typical text patterns as they produce and read texts. It has become common today to describe text patterns as typical sets of manifestations of formal, thematic, and pragmatic features that arise from resemblances between different texts and that are inscribed in the communicative memories of a language community. However, speakers also transcend text patterns every day and oscillate between following and overstepping textual rules. This thesis investigates how speakers categorize linguistic knowledge in text patterns, and follow and transcend these patterns in everyday communication, using the example of Rainald Goetz’ text Loslabern. Excerpts from reviews about Loslabern illustrate how readers perceive the text: Some readers consider Loslabern as a ‘ruined’ text that falls apart, whereas others describe Loslabern as ‘ocean-like’ and fluid. Based on these reader experiences, the thesis attempts to answer the following central question: How can we describe ‘Loslabern’ and connatural texts from the viewpoint of textual linguistics in accordance with the readers’ intuitions? The thesis proposes and discusses three options: Textual linguistics may describe Loslabern i) as a broken text, ii) in terms of different concepts of text pattern, and iii) in terms of a novel concept of text pattern. The analytical section focuses on a discussion of different concepts of text pattern: discrete structural and prototypical pragmatic concepts. It examines how these concepts fall short of describing Loslabern in accordance with the readers’ intuitions. Following Wittgenstein and his concept of family resemblance, it creates a multi-dimensional and open concept of text patterns. This concept enables textual linguistics to depict the intertextual embeddedness of Loslabern and other texts systematically, to gain insight into the mechanisms of forming and transcending text patterns, and to describe Loslabern in accordance with the diversity of readers’ intuitions. In doing so, the thesis points at new directions in linguistics as well as literary studies.

There are unique cases when designing products where a prototype is required to demonstrate critical operations of a system or subsystem such that it will serve as a basis for how the design will move forward. These prototypes are oftentimes on the critical design path. Due to the fact there is typically some aspect of a prototype that is not well understood there can be a considerable amount of uncertainty associated with the amount of resources needed to design such a prototype. The goal of this thesis is to address how to systematically reduce uncertainty for the purpose of creating a robust cost estimate. This statement does highlight the problem of defining what a robust estimate is, which results in addressing the key question driving this research: "When is enough information gathered to generate a robust estimate for the design of prototype systems?" The crux of the problem lies in how to characterize the interactions and uncertainty associated with cost, schedule, and performance. Additionally, the breakdown of a prototype system into its subsystems results in errors exist at each division. The result is a cost estimation method that has been generated by leveraging the principles of design methodology. Two test cases are applied including one theoretical model, and one project from the Georgia Tech Research Institute (GTRI). The GTRI project was work performed for the Georgia Department of Transportation related to the filling of cracks on asphalt road surfaces. These examples are evaluated from the view point of the Validation Square in order to verify the effectiveness beyond example problems.

published_or_final_version / abstract / toc / Industrial and Manufacturing Systems Engineering / Master / Master of Philosophy

published_or_final_version / Industrial and Manufacturing Systems Engineering / Master / Master of Philosophy

No description available.

No description available.

This thesis investigates the boundary of human rationality and how psychological processes interact with underlying regularities in the environment and affect beliefs and achievement. Two common modes in everyday experiential learning, supervised and unsupervised learning were hypothesized to tap different ecological and epistemological approaches to human adaptation; the Brunswikian and the Gibsonian approach. In addition, they were expected to be differentially effective for achievement depending on underlying regularities in the task environment. The first approach assumes that people use top-down processes and learn from hypothesis testing and external feedback, while the latter assumes that people are receptive to environmental stimuli and learn from bottom-up processes, without mediating inferences and support from external feedback, only exploratory observations and actions. Study I investigates selective supervised learning and showed that biased beliefs arise when people store inferences about category members when information is partially absent. This constructivist coding of pseudo-exemplars in memory yields a conservative bias in the relative frequency of targeted category members when the information is constrained by the decision maker’s own selective sampling behavior, suggesting that niche picking and risk aversion contribute to conservatism or inertia in human belief systems. However, a liberal bias in the relative frequency of targeted category members is more likely when information is constrained by the external environment. This result suggests that highly exaggerated beliefs and risky behaviors may be more likely in environments where information is systematically manipulated, for example when positive examples are highlighted to convey a favorable image while negative examples are systematically withheld from the public eye. Study II provides support that the learning modes engage different processes. Supervised learning is more accurate in less complex linear task environments, while unsupervised learning is more accurate in complex nonlinear task environments. Study III provides further support for abstraction based on hypothesis testing in supervised learning, and abstraction based on receptive bottom-up processes in unsupervised learning that aimed to form ideal prototypes as highly valid reference points stored in memory. The studies support previous proposals that integrating the Brunswikian and the Gibsonian approach can broaden the scope of psychological research and scientific inquiry.

The complexity among embedded systems has increased dramatically in recent years. During the same time has the capacity of the hardware grown to astonishing levels. These factors have contributed to that software has taken a leading role and time-consuming role in embedded system development.Compared with regular software development, embedded development is often more restrained by factors such as hardware performance and testing capability. A solution to some of these problem has been proposed and that is a concept called virtual platforms. By emulating the hardware in a software environment, it is possible to avoid some of the problems associated with embedded software development. For example is it possible to execute a system faster than in reality and to provide a more controllable testing environment. This thesis presents a case study of an application specific virtual platform. The platform is based on already existing embedded system that is located in an industrial control system.  The virtual platform is able to execute unmodified application code at a speed twice of the real system, without causing any software faults. The simulation can also be simulated at even higher speed if some accuracy losses are regarded as acceptable.The thesis presents some tools and methods that can be used to model hardware on a functional level in an software environment. The thesis also investigates the accuracy of the virtual platform by comparing it with measurements from the physical system. In this case are the measurements mainly focused of the data transactions in a controller area network bus (CAN).

Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 14, 2008) Includes bibliographical references (p. 37-40).