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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Μεθοδολογία έγκαιρης εκτίμησης της γνώμης των χρηστών για την ποιότητα λογισμικού / A methodology for early estimation of users' opinions of software quality

Σταυρινούδης, Δημήτριος 25 June 2007 (has links)
Στην παρούσα διδακτορική διατριβή προτείνονται διάφορες μέθοδοι και τεχνικές που συνεισφέρουν στην έγκαιρη εκτίμηση της γνώμης των χρηστών για την ποιότητα λογισμικού. Τέτοιες μέθοδοι είναι α) η επιλογή και χρήση μετρικών λογισμικού και η ανάλυση των αποτελεσμάτων τους, β) η δόμηση και η ανάλυση ερωτηματολογίων για τη μέτρηση της γνώμης των χρηστών για την ποιότητα λογισμικού, γ) η συσχέτιση εσωτερικών μετρικών λογισμικού με τα εξωτερικά ποιοτικά χαρακτηριστικά ενός προγράμματος λογισμικού, δ) η μεταβολή της γνώμης του χρήστη για την ποιότητα ενός προγράμματος λογισμικού με την πάροδο του χρόνου σε σχέση με το επίπεδο εμπειρίας του χρήστη και ε) η χρήση και η προσαρμογή κανόνων και μοντέλων από τη θεωρία Αναθεώρησης Άποψης. Όλες οι παραπάνω μέθοδοι συνδυάζονται ώστε να συνεισφέρουν στην προτεινόμενη μεθοδολογία της διδακτορικής διατριβής. / In this dissertation, a number of methods and techniques that contribute to the early estimation of users’ opinions of software quality are proposed. These are a) the selection and use of software metrics and the analysis of their results, b) the formation and analysis of questionnaires measuring users’ opinions of software quality, c) the correlation between internal software metrics and the external quality characteristics of a software program, d) the differentiation of a user’s opinion of the quality of a software program over time in relation to the experience level of the user and e) the use and adaptation of rules and models of Belief Revision theory. The combination of these methods results in the proposed methodology of this dissertation.
312

Διεξαγωγή μετρήσεων ποιότητας με στόχο τη βελτίωση της συντηρησιμότητας σε λογισμικό αλληλεπίδρασης με Βάση Δεδομένων / Applying metrics to an object-oriented software interacting with a database to ensure its maintainability

Πέρδικα, Πολυτίμη 16 May 2007 (has links)
Η ποιότητα του λογισμικού είναι μία πολυσυζητημένη έννοια στις μέρες μας. Παρόλο που δεν υπάρχει ένας και μόνο ορισμός που να την περιγράφει, όλοι αντιλαμβάνονται την έννοια της ποιότητας λογισμικού, ιδιαίτερα μέσω της απουσίας της. Η διασφάλιση της ποιότητας του λογισμικού συνδέεται άμεσα με την έννοια της μετρικής, που είναι μία διαδικασία απαραίτητη για τη εκτίμηση της κατάστασης των προϊόντων, των διαδικασιών και των πόρων παραγωγής λογισμικού. Με την εφαρμογή των μετρικών σε ένα λογισμικό, μετρώνται εκείνα τα χαρακτηριστικά του που συμβάλλουν σημαντικά στην ποιότητά του. Έτσι, είναι δυνατό να εξαχθούν συμπεράσματα για το κατά πόσο το λογισμικό πληροί τα κριτήρια ποιότητας. Αντικείμενο της παρούσας διπλωματικής εργασίας είναι η παρουσίαση μεθοδολογίας διεξαγωγής μετρήσεων ποιότητας σε λογισμικό αντικειμενοστραφούς προγραμματισμού που υλοποιεί την αλληλεπίδραση με μία Βάση Δεδομένων, ώστε να εξαχθούν συμπεράσματα κυρίως για τη συντηρησιμότητά του και κατ’ επέκταση για τη δυνατότητα επαναχρησιμοποίησής του. / Although there is not a unique definition for ‘software quality’, its value is clearly understood, especially through its absence. Software quality reassurance is related with the concept of ‘metrics’. Metrics are considered essential to estimate the state of the product, the procedures and the resources for the software production. Through the application of metrics to a software product, the characteristics that contribute to its quality can be measured. In this way, conclusions can be drawn regarding the degree of fulfillment for the criteria of quality. This thesis presents a methodology of applying metrics to an object-oriented software, which is responsible for interacting with a database. The results of measuring the most important characteristics of the software lead to conclusions about the software’s maintainability and reusability.
313

Švenčionių apskrities bajorų padėtis XIX a. pirmojoje pusėje / “Status of the nobles in Švenčioniai district in the first half of the XIX century"

Volk, Albert 16 August 2007 (has links)
Ketverių metų“ seimo metu buvo nutarta dėl administracinio Vilniaus vaivadijos padalijimo. Tačiau galutinai apskritis buvo suformuota 1792 m. Ašmenos apskritis buvo padalinta išilgai Neries upės. Jos pietinė dalis liko Ašmenos apskričiai, o iš jos šiaurinės dalies buvo sudaryta nauja Užnerio apskritis su centru Pastovyje. Naujoji apskritis priklausė Vilniaus gubernijai. Sekantis administraciniai pasikeitimai vyko 1839 m. ir tęsesi iki 1843 m. Apskritis buvo padidinta ir pakeitė savo pavadinimą į Švenčionių apskritį. Apskritis buvo sudaryta iš vieno dekanato kuris 1829 m. skilo į Švenčionių ir Svyrių. Užnerio apskrities bajorai po trečiojo valstybės padalijimo pradėjo įrodinėti savo kilmė, be abėjo toks pat procesas vyko ir kitose gubernijos apskritise. Dauguma turtingų bajorų, pasirupino kilmės įrodymais iki 1830-31 m. O smulkieji bajorai, dėl liešų trukumo ir tinkamų dokumetų stokos nebegalėjo to padaryti. Del to didesnė jų dalis po sukilimo buvo eliminuota iš luomo. Bajoriškos valdos skyrėsi savo dydžių, atnešamų pelnų ir valstiečių dydži��. Apskrityje vyravo vidutinių bajorų valdos, kurios siekė iki 1000 dešimtinių. Nagrinėjant bažnytinės metrikas, sužinome, apie bajorų užrašymo būdus, kaip kunigai, juos įrašydavo i metrikas. Per 23 metus apskrityje gimė 5271 bajorų vaikas, tarp jų 55,2 procento berniukų ir 44, 8 mergaičių. Nagrinėjant nesantuokinius vaikus, paaiškėjo, jog jie dažnaiusiai gimdavo smulkiųjų bajorų šeimose. Daugiausia bajorų gimdavo kaimuose o mažiausiai... [toliau žr. visą tekstą] / During the four-year Parliament governance, it was decided for administrational division of Vilnius region. However, finally, this region was formed in 1792. Ašmena region was divided along Neris River. Its south part was left for Ašmena region and a new Užneris region of its north part with center in Pastovis was established. This new region belonged to Vilnius government. The later administrational changes were performed in 1839 and they continued up to 1843. This region was expanded and its name was changed into Švenčionys region. The region contained one deanery, which splitted into Švencionys and Svyriai in 1829. The nobles of Užneris region after the third division of the country started proving their origin. The same phenomenon happened in the others regions of the government. The majority of the rich nobles had taken care of the origin evidences before 1830-31. Small nobles could not do that due to lack of resources and documents. Because of the absence of the documents they were eliminated of the noble estate after the revolt. The nobles’ possessions were different in size, benefits and number of rustics. In this region, the biggest part of the average nobles prevailed that reached up to 1000 tithes. While anlysing church metrics, we get to know the information about the way the nobles were inscribed into metrics. It was born 5271 children of nobles over 23 years in the region; 55,2 percent of boys and 44,8 percent of girls. Irregular children were born mostly in... [to full text]
314

Degenerate Kundt Spacetimes and the Equivalence Problem

McNutt, David 20 March 2013 (has links)
This thesis is mainly focused on the equivalence problem for a subclass of Lorentzian manifolds: the degenerate Kundt spacetimes. These spacetimes are not defined uniquely by their scalar curvature invariants. To prove two metrics are diffeomorphic, one must apply Cartan's equivalence algorithm, which is a non-trivial task: in four dimensions Karlhede has adapted the algorithm to the formalism of General Relativity and significant effort has been spent applying this algorithm to particular subcases. No work has been done on the higher dimensional case. First, we study the existence of a non-spacelike symmetry in two well-known subclasses of the N dimensional degenerate Kundt spacetimes: those spacetimes with constant scalar curvature invariants (CSI) and those admitting a covariant constant null vector (CCNV). We classify the CSI and CCNV spacetimes in terms of the form of the Killing vector giving constraints for the metric functions in each case. For the rest of the thesis we fix N=4 and study a subclass of the CSI spacetimes: the CSI-? spacetimes, in which all scalar curvature invariants vanish except those constructed from the cosmological constant. We produce an invariant characterization of all CSI-? spacetimes. The Petrov type N solutions have been classified using two scalar invariants. However, this classification is incomplete: given two plane-fronted gravitational waves in which both pairs of invariants are similar, one cannot prove the two metrics are equivalent. Even in this relatively simple subclass, the Karlhede algorithm is non-trivial to implement. We apply the Karlhede algorithm to the collection of vacuum Type N VSI (CSI-?, ? = 0) spacetimes consisting of the vacuum PP-wave and vacuum Kundt wave spacetimes. We show that the upper-bound needed to classify any Type N vacuum VSI metric is four. In the case of the vacuum PP-waves we have proven that the upper-bound is sharp, while in the case of the Kundt waves we have lowered the upper-bound from five to four. We also produce a suite of invariants that characterize each set of non-equivalent metrics in this collection. As an application we show how these invariants may be related to the physical interpretation of the vacuum plane wave spacetimes.
315

Assessing Cumulative Effects in Georgian Bay, Ontario Using a Food Web Structure as a Metric

Salt, Rachel 30 August 2013 (has links)
Cumulative effects, often minor individually but collectively significant, are continually being grappled with by researchers, policy makers and practitioners. Despite this the Canadian approach to cumulative effects assessment is thought by many to be ineffective. In this thesis I investigate the literature that surrounds cumulative effects and uncovered three distinct themes that occur chronologically: genesis, project-based approach and integration. During the genesis phase cumulative effects nomenclature, ideas and frameworks was created. The main theme of this era was to asses these effects at a large scale and to have a strong understanding of a systems ecology prior to the assessment. This approach was found to be too complex and so a more narrow project-based approach was implemented and still remains today. This approach is heavily criticized and as such researchers are now trying to find an approach that integrates these two divergent themes into a regional level assessment. I have found there to be several frameworks but an absence of effective regional methodologies. There is a need for regional metrics if this approach is to ever be institutionally supported. Food web structure can be evaluated at multiple scales and has been shown to be responsive to environmental variation; thus, it has potential for application as a metric for cumulative effects. Here, using stable isotope analysis, I field test integrative measures of food web structure (food chain length, habitat coupling, trophic omnivory) at sites of varying degrees of anthropogenic stressors in Georgian Bay, Ontario to evaluate the use of food webs as a metric for cumulative effects assessment. I found that food web structure varied significantly among sites. Sites with high levels of stress displayed structural characteristics reflective of human activities such as shorter food chain lengths, increased trophic omnivory, and reduced habitat coupling relative to the non-stressed sites. These results indicate that food web structure as an ecosystem level metric may provide insight into anthropogenic activities, and may be applied routinely as a metric for doing Cumulative Effects Assessment. / University of Guelph, Saugeen Ojibway Nation, Georgian Bay Forever
316

Techniques and Tools for Mining Pre-Deployment Testing Data

Chan, BRIAN 17 September 2009 (has links)
Pre-deployment field testing in is the process of testing software to uncover unforeseen problems before it is released in the market. It is commonly conducted by recruiting users to experiment with the software in as natural setting as possible. Information regarding the software is then sent to the developers as logs. Log data helps developers fix bugs and better understand the user behaviors so they can refine functionality to user needs. More importantly, logs contain specific problems as well as call traces that can be used by developers to trace its origins. However, developers focus their analysis on post-deployment data such as bug reports and CVS data to resolve problems, which has the disadvantage of releasing software before it can be optimized. Therefore, more techniques are needed to harness field testing data to reduce post deployment problems. We propose techniques to process log data generated by users in order to resolve problems in the application before its deployment. We introduce a metric system to predict the user perceived quality in software if it were to be released into market in its current state. We also provide visualization techniques which can identify the state of problems and patterns of problem interaction with users that provide insight into solving the problems. The visualization techniques can also be extended to determine the point of origin of a problem, to resolve it more efficiently. Additionally, we devise a method to determine the priority of reported problems. The results generated from the case studies on mobile software applications. The metric results showed a strong ability predict the number of reported bugs in the software after its release. The visualization techniques uncovered problem patterns that provided insight to developers to the relationship between problems and users themselves. Our analysis on the characteristics of problems determined the highest priority problems and their distribution among users. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2009-09-16 17:50:31.094
317

Measuring Incrementally Developed Model Transformations Using Change Metrics

Paen, EYRAK 28 September 2012 (has links)
Transformations play a central role in Model Based Software Engineering. Similar to the development of other types of software, a transformation's specification and implementation does not necessarily remain static over the course of a project's lifetime; the transformation may develop incrementally and evolve. The goal of this thesis is to propose metrics that can be used to characterize the evolution of model transformations. To perform an initial demonstration of the metrics, this thesis considers an incrementally defined model transformation task. The transformation is implemented using two model transformation languages, a textual language and a graphical language, and metrics are extracted from the historical artifacts. The thesis defines a set of change metrics based on an abstract syntax difference model. Language feature metrics are also defined for both transformation languages. A process for extracting model-based change metrics and language metrics from the abstract syntax of the transformation languages is introduced. The applicability of the metrics in characterizing changes is demonstrated using exploratory clustering analysis on a transformation task. We show how, for this transformation task using both languages, metrics derived from the difference model result in clusters that reflect characteristics of individual changes, in contrast to clusters obtained with language metrics. / Thesis (Master, Computing) -- Queen's University, 2012-09-28 10:47:10.999
318

Représentation et détection des images et des surfaces déformables

Barolet, Justine C. 08 1900 (has links)
La représentation d'une surface, son lissage et son utilisation pour l'identification, la comparaison, la classification, et l'étude des variations de volume, de courbure ou de topologie sont omniprésentes dans l'aire de la numérisation. Parmi les méthodes mathématiques, nous avons retenu les transformations difféomorphiques d'un pattern de référence. Il y a un grand intérêt théorique et numérique à approcher un difféomorphisme arbitraire par des difféomorphismes engendrés par des champs de vitesses. Sur le plan théorique la question est : "est-ce que le sous-groupe de difféomorphismes engendrés par des champs de vitesses est dense dans le groupe plus large de Micheletti pour la métrique de Courant ?" Malgré quelques progrès réalisés ici, cette question demeure ouverte. Les pistes empruntées ont alors convergé vers le sous-groupe de Azencott et de Trouvé et sa métrique dans le cadre de l'imagerie. Elle correspond à une notion de géodésique entre deux difféomorphismes dans leur sous-groupe. L'optimisation est utilisée pour obtenir un système d'équations état adjoint caractérisant la solution optimale du problème d'identification à partir des observations. Cette approche est adaptée à l'identification de surfaces obtenues par un numériseur tel que, par exemple, le scan d'un visage. Ce problème est beaucoup plus difficile que celui d'imagerie. On doit alors introduire un système de référence courbe et une surface à facettes pour les calculs. On donne la formulation du problème d'identification et du calcul du changement de volume par rapport à un scan de référence. / The representation of a surface, its smoothing, and its use in identification, comparison, classification, and in the study of changes in volume, curvature, and topology are ubiquitous in the area of the scanning. Among mathematical methods, we have retained the diffeomorphisms of a reference pattern. There is a considerable interest, both theoretical and numerical, in approximating an arbitrary diffeomorphism by diffeomorphisms generated by velocity fields. On the theoretical front the question is : "is the subgroup of diffeomorphisms generated by velocity fields dense in Micheletti's larger group endowed with the Courant metric ?" In spite of some progress, the question remains open. The tracks followed have converged towards the subgroup of Lipschitzian diffeomorphisms of Azencott and Trouvé and its metric developed for imaging. It corresponds to a notion of geodesic between two diffeomorphisms in their subgroup. Optimization is then used to obtain a system of equations of the state adjoint state type characterizing the optimal solution of the identification problem from observations. This approach is adapted to the identification of surfaces obtained from a scanner such as, for instance, the scan of a face. This problem is much more difficult than the one of imaging. We introduce a curvilinear reference system and a faceted surface for numerical computations. We provide a formulation of the identification problem and of the computation of the change of volume from a reference scan.
319

The Human Lever: An Examination of Investments in Human Capital for Profit-Seeking Firms

Gaitan, Malissa M 01 January 2014 (has links)
This study examines the relationship between investments in human capital and financial performance among U.S. profit-seeking firms. Specifically, it examines whether companies with greater emphasis in human capital are associated with higher profitability later on. The literature covers material ranging from accumulated information on the economy, organizational psychology, academic papers, national surveys, management literature, and workforce studies. The methodology tests a sample of companies from the Fortune 100’s Best Companies to Work For rank. Using correlations, regression analyses, and an analysis of further tests on Fortune 100 firms, the study provides evidence of a positive relationship between higher rankings and higher accounting ratios of NPM, ROE, and ROA. The paper has implications for managers to use human capital as a profit lever. Proper investments can be made using accounting and finance tools to better assess and invest in their employees.
320

EXERGY BASED METHOD FOR SUSTAINABLE ENERGY UTILIZATION ANALYSIS OF A NET SHAPE MANUFACTURING SYSTEM

SANKARA, JAYASANKAR 01 January 2005 (has links)
The approach advocated in this work implements energy/exergy analysis and indirectly an irreversibility evaluation to a continuous manufacturing process involving discrete net shape production of compact heat exchangers through a complex controlled atmosphere brazing (CAB) process. The system under consideration involves fifteen cells of a continuous ramp-up heating, melting, reactive flow, isothermal dwell, and rapid quench solidification processing sequence during a controlled atmosphere brazing of aluminum compact heat exchangers. Detailed mass, energy, and exergy balances were performed. The irreversibility sources were identified and the quality of energy utilization at different processing steps determined. It is demonstrated that advanced thermodynamics metrics based on entropy generation may indicate the level of sustainable energy utilization of transient open systems, such as in manufacturing. This indicator may be related to particular property uniformity during materials processing. In such a case, the property uniformity would indicate systems distance from equilibrium, i.e., from the process sustainable energy utilization level. This idea is applied to net shape manufacturing process considered. A metric based on exergy destruction is devised to relate the heat exchanger temperature uniformity and the quality. The idea advocated in this thesis will represent the coherent framework for developing energy efficient, economically affordable and environmentally friendly manufacturing technology.

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