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Thesis (M.S.)--University of Tennessee, Knoxville, 2003. / Title from title page screen (viewed Sept. 23, 2003). Thesis advisor: Christopher Pionke. Document formatted into pages (xv, 314 p. : ill. (some col.)). Vita. Includes bibliographical references (p. 137-139).

A memory consistency model for a language defines the order of memory operations performed by each thread in a parallel execution. Such a constraint is necessary to prevent the compiler and hardware optimizations from reordering certain memory operations, since such reordering might lead to unintuitive results. In this thesis, we propose a memory consistency model for Chapel, a parallel programming language from Cray Inc. Our memory model for Chapel is based on the idea of multiresolution and aims to provide a migration path from a program that is easy to reason about to a program that has better performance efficiency. Our model allows a programmer to write a parallel program with sequential consistency semantics, and then migrate to a performance-oriented version by increasingly changing different parts of the program to follow relaxed semantics. Sequential semantics helps in reasoning about the correctness of the parallel program and is provided by the strict sequential consistency model in our proposed memory model. The performance-oriented versions can be obtained either by using the compiler sequential consistency model, which maintains the sequential semantics, or by the relaxed consistency model, which maintains consistency only at global synchronization points. Our proposed memory model for Chapel thus combines strict sequential consistency model, compiler sequential consistency model and relaxed consistency model. We analyze the performance of the three consistency models by implementing three applications: Barnes-Hut, FFT and Random-Access in Chapel, and the hybrid model of MPI and Pthread. We conclude the following: The strict sequential consistency model is the best model to determine algorithmic errors in the applications, though it leads to the worst performance; the relaxed consistency model gives the best performance among the three models, but relies on the programmer to enforce synchronization correctly; the performance of the compiler sequential model depends on accuracy of the dependence analysis performed by the compiler; the relative performance of the consistency models across Chapel and the hybrid programming model of MPI and Pthread are the same. This shows that our model is not tightly bound to Chapel and can be applied on other programming models/languages. / text

Vykstant nuolatiniam programų sistemų atnaujinimui, nuolatos reikia prižiūrėti, kad jos būtų kokybiškai projektuojamos ir programuojamos. Tačiau neišvengiamai atsiranda nekokybiško išeities teksto, arba atsiranda projektavimo trūkumų. Todėl yra svarbu mokėti ieškoti tokias problemas, ir jas ištaisyti. Šio darbo tikslas yra sukurti automatinio – universalaus įrankio modelį, kuris savarankiškai aptiktų pertvarkas, bei būtų nepriklausomas nuo konkrečios programavimo kalbos. Šiam tikslui pasiekti yra nagrinėjami mokslininkų siūlomi automatiškai aptinkantys pertvarkas metodai. Taip pat yra nagrinėjamos tokio įrankio realizavimo galimybės, pateikti realizaciniai sprendimai ir pavyzdžiai. Taip pat tikslas yra sukurti praktiškai naudingas automatines pertvarkas, kurios būtų realizuotos pasiūlytu įrankiu, ir pademonstruotas jų veikimas. Šis įrankis naudoja loginį programavimą, kurio faktais yra aprašomos pertvarkomos programos, o taisyklėmis – pačios pertvarkų programos. Sėkmingai sukurti automatiniai pertvarkų radimo pavyzdžiai, leidžia daryti išvadą, kad šiame darbe rastas būdas automatiškai aptikti nekokybišką išeities tekstą, bei realizuoti tokias pertvarkas nepriklausomai nuo programavimo kalbos. / In the continual evolution of software systems, should be continuous to ensure that they are high quality designed and programmed. But inevitably the defective code, that call “bad small” or the design deficiencies. It is therefore important to be able to find such problems, and to correct them. The aim of this thesis is to create automatic - universal refactoring tool, which is detected in self-refactoring, and is independent of specific programming languages. To achieve this objective are scientists considered the proposed automatic detection of refactoring methods. It is also considered the possibility of the realization of such a tool, to provide examples and realizable solutions. It also aims to create a practical benefit of the automatic adjustments to the proposed tool is to be realized, and a demonstration of their operation. This tool uses a logic programming, which is a factual description of the conversion, and the rules - the refactoring of the program. The successful creation of automatic detection for refactoring, it can be concluded that this work is found way to automatically detect poor quality of source code, and the realization of the restructuring, regardless of programming language.

Source transformation systems are special-purpose programming languages, or in some cases suites of languages, that are designed for the analysis and transformation of computer languages. They enable rapid prototyping of programming languages, source code renovation, language-to-language translation, design recovery, and other custom analysis techniques. With the emergence of these systems a serious problem is evident: expressing a parser for common computer languages is sometimes very difficult. Source transformation systems employ generalized parsing algorithms, and while these are well suited for the kind of agile parsing techniques in use by transformation practitioners, they are not well suited for parsing languages that are context-dependent. Traditional deterministic parser generators do not stumble in this area, but they sacrifice the generalized parsing abilities that transformation systems depend on. When it is hard to get the input into the system as a correct and accurate parse tree the utility of the unified transformation environment is degraded and more ad hoc approaches become attractive for processing input. This thesis is about the design of a new computer language transformation system with a focus on enhancing the parsing system to support generalized context-dependent parsing. We argue for the use of backtracking LR as the generalized parsing algorithm. We present an enhancement to backtracking LR that allows us to control the parsing of an ambiguous grammar by ordering the productions of the grammar definitions. We add a grammar-dependent lexical solution and integrate it with our ordered choice parsing strategy. We design a transformation language that is closer to general-purpose programming languages, yet enables common transformation techniques. We add semantic actions to our backtracking LR parsing engine and encourage the modification of global state in support of context-dependent parsing. We introduce semantic undo actions for reverting changes to global state during backtracking, thereby enabling generalized context-dependent parsing. Finally, we free the user from having to write undo actions by employing automatic reverse execution. The resulting system allows a wider variety of computer languages to be analyzed. By focusing on improving parsing abilities and moving to a transformation language that resembles general-purpose languages, we aim to extend the transformation paradigm to allow greater use by practitioners who face an immediate need to parse, analyze and transform computer languages. / Thesis (Ph.D, Computing) -- Queen's University, 2008-12-15 21:01:24.236

This thesis presents research to build and evaluate embedding of a textual form of state machines into high-level programming languages. The work entailed adding state machine syntax and code generation to the Umple model-oriented programming technology. The added concepts include states, transitions, actions, and composite states as found in the Unified Modeling Language (UML). This approach allows software developers to take advantage of the modeling abstractions in their textual environments, without sacrificing the value added of visual modeling. Our efforts in developing state machines in Umple followed a test-driven approach to ensure high quality and usability of the technology. We have also developed a syntax-directed editor for Umple, similar to those available to other high-level programming languages. We conducted a grounded theory study of Umple users and used the findings iteratively to guide our experimental development. Finally, we conducted a controlled experiment to evaluate the effectiveness of our approach. By enhancing the code to be almost as expressive as the model, we further support model-code duality; the notion that both model and code are two faces for the same coin. Systems can be and should be equally-well specified textually and diagrammatically. Such duality will benefit both modelers and coders alike. Our work suggests that code enhanced with state machine modeling abstractions is semantically equivalent to visual state machine models. The flow of the thesis is as follows; the research hypothesis and questions are presented in “Chapter 1: Introduction”. The background is explored in “Chapter 2: Background”. “Chapter 3: Syntax and semantics of simple state machines” and “Chapter 4: Syntax and semantics of composite state machines” investigate simple and composite state machines in Umple, respectively. “Chapter 5: Implementation of composite state machines” presents the approach we adopt for the implementation of composite state machines that avoids explosion of the amount of generated code. From this point on, the thesis presents empirical work. A grounded theory study is presented in “Chapter 6: A Grounded theory study of Umple”, followed by a controlled experiment in “Chapter 7: Experimentation”. These two chapters constitute our validation and evaluation of Umple research. Related and future work is presented in “Chapter 8: Related work”.

Programming is a difficult activity because it requires thinking in a way that ordinary people are not familiar with. It becomes more complex considering the unusual and sometimes contradictory (with daily life usage) symbols when designing programming languages. This thesis introduces an experimental programming language called TPD, which is designed to reduce the syntax- and semantics-oriented difficulties to a minimum and provide a head start in programming to high school students and novice programmers who are native speakers of Turkish. TPD mimics Turkish syntax in order to obtain a better learning curve by making use of the user&#039 / s native language competence in learning the essentials of programming. TPD supports both imperative (procedural) and functional paradigms. General lists are provided as a built-in data type. Given the educational concerns, the design of the programming language goes hand in hand with the design of the development environment. Diagnostic features of the compiler are emphasized. Generated target code is in Java. The development environment features a graphical interface and a language-based editor.

Program comprehension is the process of gaining knowledge about software system by extracting it from its source code or observing its behavior at runtime. Often, when documentation is unavailable or missing, this is the only reliable source of knowledge about the system, and the fact that up to 50% of total maintenance effort is spent understanding the system makes it even more important. The source code of large software systems contains thousands, sometimes millions of lines of code, motivating the need for automation, which can be achieved with the help of program comprehension tools. This makes comprehension tools an essential factor in the adoption of new programming languages. This work proposes a way to fill this gap in the ecosystem of Swift, a new, innovative programming language aiming to cover a wide range of applications while being safe, expressive, and performant. The proposed solution is to bridge the gap between Swift and VizzAnalyzer, a program analysis framework featuring a range of analyses and visualizations, as well as modular architecture which makes adding new analyses and visualizations easier. The idea is to define a formal model for representing Swift programs and mapping it to the common program model used by VizzAnalyzer as the basis for analyses and visualizations. In addition to that, this paper discusses the differences between Swift and programming languages which are already supported by VizzAnalyzer, as well as practical aspects of extracting the models of Swift programs from their source code.

Title: Visual Programming Backend for a Mobile Robot Author: Bc. Ondřej Staněk Department: The Department of Software Engineering Supervisor: RNDr. David Obdržálek, Ph.D. Supervisor's e-mail address: David.Obdrzalek@mff.cuni.cz Abstract: In this work, the author designs and implements a solution for programming small mobile robots using a visual programming language. A suitable visual programming front-end is selected and back-end layers are created that allow execution of the program in a mobile robot. The author designs and implements a virtual machine that runs alongside the original robot firmware on an 8-bit microcontroller with limited resources. A code generator layer compiles the visual representation of the program into a sequence of bytecode instructions that is interpreted on board of the mobile robot. The solution supports typical features of procedural programming languages, in particular: variables, expressions, conditional statements, loops, static arrays, function calls and recursion. The emphasis is put on robustness of the implementation. To verify and maintain code quality, methods of automated software testing are used. Keywords: visual programming language, virtual machine, mobile robot, Blockly Powered by TCPDF (www.tcpdf.org)

abstract: Photosynthesis is the primary source of energy for most living organisms. Light harvesting complexes (LHC) play a vital role in harvesting sunlight and passing it on to the protein complexes of the electron transfer chain which create the electrochemical potential across the membrane which drives ATP synthesis. phycobilisomes (PBS) are the most important LHCs in cyanobacteria. PBS is a complex of three light harvesting proteins: phycoerythrin (PE), phycocyanin (PC) and allophycocyanin (APC). This work has been done on a newly discovered cyanobacterium called Leptolyngbya Heron Island (L.HI). This study has three important goals: 1) Sequencing, assembly and annotation of the L.HI genome - Since this is a newly discovered cyanobacterium, its genome was not previously elucidated. Illumina sequencing, a type of next generation sequencing (NGS) technology was employed to sequence the genome. Unfortunately, the natural isolate contained other contaminating and potentially symbiotic bacterial populations. A novel bioinformatics strategy for separating DNA from contaminating bacterial populations from that of L.HI was devised which involves a combination of tetranucleotide frequency, %(G+C), BLAST analysis and gene annotation. 2) Structural elucidation of phycoerythrin - Phycoerythrin is the most important protein in the PBS assembly because it is one of the few light harvesting proteins which absorbs green light. The protein was crystallized and its structure solved to a resolution of 2Å. This protein contains two chemically distinct types of chromophores: phycourobilin and phycoerythrobilin. Energy transfer calculations indicate that there is unidirectional flow of energy from phycourobilin to phycoerythrobilin. Energy transfer time constants using Forster energy transfer theory have been found to be consistent with experimental data available in literature. 3) Effect of chromatic acclimation on photosystems - Chromatic acclimation is a phenomenon in which an organism modulates the ratio of PE/PC with change in light conditions. Our investigation in case of L.HI has revealed that the PE is expressed more in green light than PC in red light. This leads to unequal harvesting of light in these two states. Therefore, photosystem II expression is increased in red-light acclimatized cells coupled with an increase in number of PBS. / Dissertation/Thesis / Ph.D. Chemistry 2014