In this thesis, a cost based process control model is formulated. A dynamic programming approach is used and along with the techniques of Bayesian decision theory, an optimal set of steady state control policies are shown to exist which are dependent upon prior beliefs about the condition of the process. It is the objective of this thesis to compare the results obtained from this approach to those of an X̅ control chart approach. The model proposed by Knappenberger and Grandage [20] is used as a basis for comparison. Numerical examples are used to illustrate each procedure. The results obtained illustrate that by using the operating policies specified by the dynamic approach, a savings of from 29% to 40% in the optimal cost per unit to operate the quality control procedure can be achieved rather than utilizing the policies of the X̅ control chart model. / Master of Science

It is well known that the cost of large-scale software systems has become unacceptably high. Software metrics by giving a quantitative view of software and its development would prove invaluable to both software designers and project managers. Although several software quality metrics have been developed to assess the psychological complexity of programming tasks, many of these metrics were not validated on any software system of significant size. This thesis reports on an effort to validate seven different software quality metrics on a medium size data base system. Three different versions of the data base system that evolved over a period of three years were analyzed in this study. A redesign of the data base system, while still in its design phase was also analyzed. The results indicate the power of software metrics in identifying the high complexity modules in the system and also improper integration of enhancements made to an existing system. The complexity values of the system components as indicated by the metrics, conform well to an intuitive understanding of the system by people familiar with the system. An analysis of the redesigned version of the data base system showed the usefulness of software metrics in the design phase by revealing a poorly structured component of the system. / Master of Science

The thesis describes the requirement, design, and implementation of a software package that can be used to perform quantitative studies on certain aspects of a programming task. Of specific interest are experiments with the level of interactiveness of the human-computer interface relating to program construction and with language design principles relating to identifier scope rules. The software package for conducting these experiments is an interactive language environment called PEEP. Its base language is Pascal and its design is based on Johnston's semantic models of computation. Storage representations and implementation of these semantic models are described. These models depicting the compile-time structure, run-time structure, and realization of the static and the dynamic scoping rules. The evolution and current research of programming environments, user interface to PEEP, and future research on PEEP are also focuses of attention. / Master of Science

Five component problem-solving skills (general strategy, planning, logical thinking, algebraic variables, and debugging) were identified as common elements of both computer programming and mathematical problem-solving. Based on the similarities of these general skills in specific contexts, a theory was generated that the skills would transfer and that experience in computer programming would cause an improvement in mathematical problem-solving achievement. A path model was constructed to illustrate this hypothesized causal relationship between computer programming and mathematical problem-solving achievement. In order to control for other relevant variables, the model also included mathematics experience, access to a home computer, ability, socioeconomic status, and gender. The model was tested with a sample of 800 high school students in seven southwest Virginia high schools. Results indicated that ability had the largest causal effect on mathematical problem-solving achievement. Three variables had a moderate effect: computer programming experience, mathematics experience, and gender. The other two variables in the model (access to a home computer and socioeconomic status) were only very slightly related to mathematical problem-solving achievement. The conclusion of the study was that there was evidence to support the theory of transfer of skills from computer programming experience to mathematical problem-solving. Once ability and gender were controlled, computer programming experience and mathematics experience both had causal effects on mathematical problem-solving achievement. This suggests that to maximize mathematical problem-solving scores, a curriculum should include both mathematics and computer programming experiences. / Ed. D.

Programmers are encouraged to comment their source programs, yet the value of the comments is not easily verified. In this study, the relationships between comment quantity and software metrics are assessed to determine whether programmers increase comment quantity in complex modules. In addition, comment quantity and software metrics are related to software maintenance data. It was found that software complexity, as measured by software metrics, accounts for a substantial portion of the variance in comment quantity. Additionally, comment quantity has no statistically significant relationship to software maintainability for the task studied. / Master of Science

published_or_final_version / Education / Master / Master of Science in Information Technology in Education

Thesis (M. Ed.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 78-82).

Thesis (M.Ed.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 78-82). Also available in print.

The C Navigational System (CNS) is a proposed programming environment for the C programming language. The introduction covers the major influences of programming environments and the components of a programming environment. The system is designed to support the design, coding and maintenance phases of software development. CNS provides multiple views to both the source and documentation for a programming project. User-defined and system-defined links allow the source and documentation to be hierarchically searched. CNS also creates a history list and function interface for each function in a module. The final chapter compares CNS and several other programming environments (Microscope, Rn, Cedar, PECAN, and Marvel).

Les structures protéiques peuvent être divisées en répétitives et apériodiques, les structures apériodiques correspondant pour la plupart à des protéines globulaires. Les protéines répétitives (PRs) contiennent des unités de répétitions adjacentes, appelées séquences répétées en tandem (TRs). Les PRs sont abondantes et ont une importance fonctionnelle fondamentale. De plus de nombreuses études ont démontré l'implication des TRs dans les pathologies humaines. Ainsi, la découverte des PRs et la compréhension de leur relation séquence-structure-fonction, offrent des perspectives de recherche prometteuses.Le développement d’initiatives en génomique structurale, combiné à une meilleure adaptation des techniques de cristallographie et de RMN à l’étude des protéines non globulaires, a permis d’élucider la structure d’un nombre croissant de PRs, d’où la nécessité de mettre en place un système de classification. Les structures répétitives ont été réparties en cinq classes, principalement fondées sur la longueur des TRs: Classe I - agrégats cristallins; Classe II - structures fibreuses; Classe III - structures allongées, dont la stabilité dépend des interactions qui s’établissent entre les motifs répétés. Classe IV - structures répétitives fermées ; Classe V - structures en collier de perles. Les efforts de ces dernières années ont abouti au développement d’outils bioinformatiques utiles à la détection et l'analyse d'éléments répétitifs présents au sein des structures protéiques (3D TRs). En fonction des caractéristiques des répétitions, certaines méthodes fonctionnent mieux que d'autres, mais, jusqu’à présent, aucune ne permettait de couvrir toute la gamme des répétitions. Ce constat nous a incités à développer une nouvelle méthode, appelée détecteur de protéines en tandem (TAPO). TAPO exploite les périodicités des coordonnées atomiques ainsi que d'autres types de représentation structurale, comprenant les chaînes générées par un alphabet conformationnel, les cartes de contact entre résidus, et les arrangements en vecteurs d'éléments de structure secondaire. Actuellement, sept scores, issus des caractéristiques analysées par TAPO, sont combinés à l’aide d’une Machine à Vecteur Support pour produire un score final permettant de différencier les protéines renfermant ou non des 3D TRs. En atteignant 94% de sensibilité et 97% de spécificité pour la référence actuelle, TAPO présente des performances améliorées par rapport aux autres méthodes de pointe. Le développement de TAPO offre de nouvelles opportunités pour l’analyse à grande échelle des protéines renfermant des 3D TRs. Ainsi, notre analyse de la base de données PDB, à l’aide de TAPO, a montré que 19% des protéines contiennent des 3D TRs. L'analyse à grande échelle des structures 3D TRs dans PDB nous a également permis de découvrir plusieurs nouveaux types de structures répétitives, absents de la classification existante et dont certains sont décrits ici.Nous avons entrepris une analyse complète des 3D TRs constitutifs du Rossmann Fold (RF). Notre intérêt pour les RFs a été suscité par le fait que de nombreuses protéines RFs représentent un cas ambigüe vis à vis des structures répétitives et non répétitives. A priori, les unités hélice α - feuillet β des RFs devraient avoir une forte tendance à s’empiler et donc, à former des structures répétitives. Afin de déterminer la fréquence à laquelle les RFs forment de longues unités de répétition empilées, nous avons sélectionné, à l’aide de TAPO, des structures contenant des RFs et les avons classées. Notre analyse montre que les RFs typiques ne peuvent pas être clairement définis comme des structures répétitives mais plutôt comme des unités de structures globulaires, comptant au plus trois répétitions α-β. Des éléments de discussion seront proposés pour tenter d’expliquer cette observation surprenante. / In general, protein structures can be divided into: repetitive and aperiodic structures. Most of the aperiodic structures are globular proteins. The repetitive proteins contain arrays of repeats that are adjacent to each other, called Tandem Repeats (TRs). Proteins containing TRs are abundant and have fundamental functional importance. Numerous studies demonstrated the involvement of such TR-containing proteins in human diseases. Furthermore, genetic instability of these regions can lead to emerging infection threats. Additionally, TR-containing structures have generated significant interest with respect to protein design as they can make excellent scaffolds for specific recognition of target molecules. Therefore, the discovery of these domains, understanding of their sequence–structure–function relationship promises to be a fertile direction for research.The growth of structural genomics initiatives, in combination with improvements in crystallographic and NMR techniques aimed at non-globular proteins, has resulted in an increase in structurally elucidated TR proteins. This has necessitated the development of classification schemes. Structural repeats were broadly divided into five classes mainly based on repeat length; Class I – crystalline aggregates; Class II – fibrous structures such as collagen; Class III – elongated structures where the repetitive units require each other for structural stability such as solenoid proteins; Class IV – closed repetitive structures, such as TIM-barrels and Class V – bead on a string structures such as tandems of Ig-fold domains. Despite this progress, the majority of bioinformatics approaches have focused on non-repetitive globular proteins.In recent years, efforts have been made to develop bioinformatics tools for the detection and analysis of repetitive elements in protein structures (3D TRs). Depending on the size and character of the repeats, some methods perform better than others, but currently no best approach exists to cover the whole range of repeats. This served as a motivation for the development of our method called the TAndem PrOtein detector (TAPO). TAPO exploits, periodicities of atomic coordinates and other types of structural representation, including strings generated by conformational alphabets, residue contact maps, and arrangements of vectors of secondary structure elements. Currently, seven feature based scores produced by TAPO are combined using a Support Vector Machine, producing a score to enable the differentiation between proteins with and without 3D TRs. TAPO shows an improved performance over other cutting edge methods, achieving 94% sensitivity and 97% specificity on the current benchmark. The development of TAPO provided new opportunities for large scale analysis of proteins with 3D TRs. In accordance with our analysis of PDB using TAPO, 19% of proteins contain 3D TRs. The large scale analysis of the 3D TR structures in PDB also allows us to discover several new types of TR structures that were absent in the existing classification. Some of them are described in the thesis manuscript. This suggests that TAPO can be used to regularly update the collection and classification of existing repetitive structures. In particular, a comprehensive analysis of 3D TRs related to Rossmann Fold (RF) was undertaken. Our special interest in RFs was based on the observation that many proteins with RFs represent borderline cases between repetitive and non-repetitive structures. In principle, α-helix-β-strand units of RFs should have a strong potential to stack one over the other, forming repetitive structures. To probe the question of how frequently RFs form long arrays of stacked repeats, we selected by using TAPO known RF-containing structures and classified them. Our analysis shows that typical RFs cannot be clearly defined as repetitive, rather they are part of globular structures with up to 3 αβ-repeats. We provide some explanations for this surprising observation.