Finite-State Abstractions for Probabilistic Computation Tree Logic

Probabilistic Computation Tree Logic (PCTL) is the established temporal logic for probabilistic verification of discrete-time Markov chains. Probabilistic model checking is a technique that verifies or refutes whether a property specified in this logic holds in a Markov chain. But Markov chains are often infinite or too large for this technique to apply. A standard solution to this problem is to convert the Markov chain to an abstract model and to model check that abstract model. The problem this thesis therefore studies is whether or when such finite abstractions of Markov chains for model checking PCTL exist. This thesis makes the following contributions. We identify a sizeable fragment of PCTL for which 3-valued Markov chains can serve as finite abstractions; this fragment is maximal for those abstractions and subsumes many practically relevant specifications including, e.g., reachability. We also develop game-theoretic foundations for the semantics of PCTL over Markov chains by capturing the standard PCTL semantics via a two-player games. These games, finally, inspire a notion of p-automata, which accept entire Markov chains. We show that p-automata subsume PCTL and Markov chains; that their languages of Markov chains have pleasant closure properties; and that the complexity of deciding acceptance matches that of probabilistic model checking for p-automata representing PCTL formulae. In addition, we offer a simulation between p-automata that under-approximates language containment. These results then allow us to show that p-automata comprise a solution to the problem studied in this thesis

Structures in Real Theory Application: A Study in Feasible Epistemology

This thesis considers the following problem: What methods should the epistemology of science use to gain insight into the structure and behaviour of scientific knowledge and method in actual scientific practice? After arguing that the elucidation of epistemological and methodological phenomena in science requires a method that is rooted in formal methods, I consider two alternative methods for epistemology of science. One approach is the classical approaches of the syntactic and semantic views of theories. I show that typical approaches of this sort are inadequate and inaccurate in their representation of scientific knowledge by showing how they fail to account for and misrepresent important epistemological structure and behaviour in science. The other method for epistemology of science I consider is modeled on the methods used to construct valid models of natural phenomena in applied mathematics. This new epistemological method is itself a modeling method that is developed through the detailed consideration of two main examples of theory application in science: double pendulum systems and the modeling of near-Earth objects to compute probability of future Earth impact. I show that not only does this new method accurately represent actual methods used to apply theories in applied mathematics, it also reveals interesting structural and behavioural patterns in the application process and gives insight into what underlies the stability of methods of application. I therefore conclude that for epistemology of science to develop fully as a scientific discipline it must use methods from applied mathematics, not only methods from pure mathematics and metamathematics as traditional formal epistemology of science has done

Topics in Programming Languages, a Philosophical Analysis through the case of Prolog

[EN]Programming languages seldom find proper anchorage in philosophy of logic, language and science. is more, philosophy of language seems to be restricted to natural languages and linguistics, and even philosophy of logic is rarely framed into programming languages topics. The logic programming paradigm and Prolog are, thus, the most adequate paradigm and programming language to work on this subject, combining natural language processing and linguistics, logic programming and constriction methodology on both algorithms and procedures, on an overall philosophizing declarative status. Not only this, but the dimension of the Fifth Generation Computer system related to strong Al wherein Prolog took a major role. and its historical frame in the very crucial dialectic between procedural and declarative paradigms, structuralist and empiricist biases, serves, in exemplar form, to treat straight ahead philosophy of logic, language and science in the contemporaneous age as well. In recounting Prolog's philosophical, mechanical and algorithmic harbingers, the opportunity is open to various routes. We herein shall exemplify some: - the mechanical-computational background explored by Pascal, Leibniz, Boole, Jacquard, Babbage, Konrad Zuse, until reaching to the ACE (Alan Turing) and EDVAC (von Neumann), offering the backbone in computer architecture, and the work of Turing, Church, Gödel, Kleene, von Neumann, Shannon, and others on computability, in parallel lines, throughly studied in detail, permit us to interpret ahead the evolving realm of programming languages. The proper line from lambda-calculus, to the Algol-family, the declarative and procedural split with the C language and Prolog, and the ensuing branching and programming languages explosion and further delimitation, are thereupon inspected as to relate them with the proper syntax, semantics and philosophical élan of logic programming and Prolog

Cosmology: The Impossible Integration?

My dissertation introduces a new account of how empirical methods and lines of evidence can come to bear on cosmological model-building. Through a careful study of the recent history of cosmology and dark matter research, I explicate a new type of justification for experiments, a `method-driven logic'. This structure of justification underlies terrestrial experiments researching dark matter and dark energy, but it is more generally prevalent in cases of an underdescribed target. Using a method-driven logic comes with a cost, however. Specifically, interpreting the empirical results of experiments justified through a method-driven logic is non-trivial: negative results warrant secure constraints on the space of possibilities for the target, whereas significant positive results remain ambivalent. While this ambivalence can be resolved through the amalgamation of multiple lines of evidence, this solution is sometimes faced with conflicts between those lines of evidence. I propose that, under specific circumstances, restricting the relevant empirical evidence can be warranted. Finally, I discuss the use of cosmological evidence as a constraint in other subfields of physics. This brings me full-circle on the integration of disciplines in cosmology|an integration driven by experimental practice

Future Computer Requirements for Computational Aerodynamics

Recent advances in computational aerodynamics are discussed as well as motivations for and potential benefits of a National Aerodynamic Simulation Facility having the capability to solve fluid dynamic equations at speeds two to three orders of magnitude faster than presently possible with general computers. Two contracted efforts to define processor architectures for such a facility are summarized

First International Conference on Ada (R) Programming Language Applications for the NASA Space Station, volume 2

Topics discussed include: reusability; mission critical issues; run time; expert systems; language issues; life cycle issues; software tools; and computers for Ada

SCADA and related technologies for irrigation district modernization

Presented at SCADA and related technologies for irrigation district modernization: a USCID water management conference on October 26-29, 2005 in Vancouver, Washington.Includes bibliographical references.Overview of Supervisory Control and Data Acquisition (SCADA) -- Total Channel Control™ - The value of automation in irrigation distribution systems -- Design and implementation of an irrigation canal SCADA -- All American Canal Monitoring Project -- Taking closed piping flowmeters to the next level - new technologies support trends in data logging and SCADA systems -- Real-time model-based dam automation: a case study of the Piute Dam -- Effective implementation of algorithm theory into PLCs -- Optimal fuzzy control for canal control structures -- SCADA over Zigbee™ -- Synchronous radio modem technology for affordable irrigation SCADA systems -- A suggested criteria for the selection of RTUs and sensors -- Irrigation canals in Spain: the integral process of modernization -- Ten years of SCADA data quality control and utilization for system management and planning modernization -- Moderately priced SCADA implementation -- Increasing peak power generation using SCADA and automation: a case study of the Kaweah River Power Authority -- Eastern Irrigation District canal automation and Supervisory Control and Data Acquisition (SCADA) -- Case study on design and construction of a regulating reservoir pumping station -- Saving water with Total Channel Control® in the Macalister Irrigation District, Australia -- Leveraging SCADA to modernize operations in the Klamath Irrigation Project -- A 2005 update on the installation of a VFD/SCADA system at Sutter Mutual Water Company -- Truckee Carson Irrigation District Turnout Water Measurement Program -- The myth of a "Turnkey" SCADA system and other lessons learned -- Canal modernization in Central California Irrigation District - case study -- Remote monitoring and operation at the Colorado River Irrigation District -- Web-based GIS decision support system for irrigation districts -- Using RiverWare as a real time river systems management tool -- Submerged venturi flume -- Ochoco Irrigation District telemetry case study -- Uinta Basin Replacement Project: a SCADA case study in managing multiple interests and adapting to loss of storage -- Training SCADA operators with real-time simulation -- Demonstration of gate control with SCADA system in Lower Rio Grande Valley, in Texas -- Incorporating sharp-crested weirs into irrigation SCADA systems

Human Factors Certification of Advanced Aviation Technologies

Proceedings of the Human Factors Certification of Advanced Aviation Technologies Conference held at the Chateau de Bonas, near Toulouse, France, 19-23 July 1993