Lors du développement d'un logiciel, plusieurs phases de test sont mises en oeuvre. Dans cette thèse, nous nous intéressons particulièrement à deux d'entre elles : les test unitaire et le test d'intégration. Dans le test unitaire, les entités du logiciel sont testées individuellement. Elles sont ensuite intégrée au sein d'un agrégat qui est soumis à un test d'intégration. Lors de cette phase, on cherche traditionnellement à tester les interactions entre ces entités. Nous nous intéressons plus particulièrement dans cette thèse au test structurel unitaire. Lors de cette phase de test, si l'entité contient des app rers d'autres entités, elles sont remplacées par des bouchons simples qui facilitent le test. Ces bouchons ne sont pas exempts de défauts. En particulier, ils sont généralement pas représentatifs des entités qu'ils remplacent. Les taux de couverture obtenus pendant le test ne représentent donc pas l'utilisatin éelle de la fonction testée. Dans cette thèse, nous proposons d'étendre la phase de test unitaire aux agrégats de fonctions. Tous les bouchons nécessaires sont produits automatiquement à partir du code des fonctions appelées. Pour cela, on se base sur une analyse et un découpage du flot de ontrôle de la fonction appelée en approximations, ainsi que sur la détermination de l'environnement particulier de chaque appel. Cet environnement ontient les informations sur les conditions d'appel à la fonction et sur l'impact de cet appel sur le flot de contrôle de la fonction appelante. On crée inalement le bouchon spécifique à un appel par filtrage des approximations par le contexte d'appel. On sélectionne ensuite une approximation pour chaque objectif de génération. L'ensemble de cette technique a été implanté au sein d'un prototype basé sur l'outil de test Inka.

Thesis--University of Copenhagen. / Summary in Danish. Bibliography: p. 71-80.

Developed by O＇Beirne and Trounson (Trounson, 2012), the UC Auditory-Visual Matrix Sentence Test (UCAMST) is an auditory-visual speech test in NZ English where sentences are assembled from 50 words arranged into 5 columns (name, verb, quantity, adjective, object). Generation of sentence materials involved cutting and re-assembling 100 naturally spoken ‟original” sentences to create a large repertoire of 100,000 unique ‟synthesised” sentences. The process of synthesising sentences from video fragments resulted in occasional artifactual image jerks (‟judders”)‒quantified by an unusually large change in the ‟pixel difference value” of consecutive frames‒at the edited transitions between video fragments. To preserve the naturalness of materials, Study 1 aimed to select transitions with the least ‟noticeable” judders. Normal-hearing participants (n = 18) assigned a 10-point noticeability rating score to 100 sentences comprising unedited ‟no judder” sentences (n = 28), and ‟synthesised” sentences (n = 72) that varied in the severity (i.e. pixel difference value), number, and position of judders. The judders were found to be significantly noticeable compared to no judder controls, and based on mean rating score, 2,494 sentences with ‟minimal noticeable judder” were included in the auditory-visual UCAMST. Follow-on work should establish equivalent lists using these sentences. The average pixel difference value was found to be a significant predictor of rating score, therefore may be used as a guide in future development of auditory-visual speech tests assembled from video fragments. The aim of Study 2 was to normalise the auditory-alone UCAMST to make each audio fragment equally intelligible in noise. In Part I, individuals with normal hearing (n = 17) assessed 400 sentences containing each file fragment presented at four different SNRs (-18.5, -15, -11.5, and -8 dB) in both constant speech-shaped noise (n = 9) and six-talker babble (n = 8). An intelligibility function was fitted to word-specific data, and the midpoint (Lmid, intelligibility at 50%) of each function was adjusted to equal the mean pre-normalisation midpoint across fragments. In Part II, 30 lists of 20 sentences were generated with relatively homogeneous frequency of matrix word use. The predicted parameters in constant noise (Lmid = 14.0 dB SNR; slope = 13.9%/dB ± 0.0%/dB) are comparable with published equivalents. The babble noise condition was, conversely, less sensitive (Lmid = 14.9 dB SNR; slope = 10.3%/dB ± 0.1%/dB), possibly due to a smaller sample size (n = 8). Overall, this research constituted an important first step in establishing the UCAMST as a reliable measure of speech recognition; follow-on work will validate the normalisation procedure carried out in this project.

The process of computerised tomography (CT) has been developed for medical imaging purposes using a variety of X-ray scannars. So far, little attention has been paid to industrial applioaticns of this technique, largely because of the constraints of expense. An investigation was made of the suitability of one medical scanner, the EMI CT5005, as an industrial scanning tool. This showed up a variety of problems when scanning non-medical objects, and suggested an alternative approach to the problem. This was to construct an experimental scanner based on gamma-ray sources, to overcome the problems of beam hardening,, and provide versatility and, perhaps, portability. The greatest limitation on this sort of device is the time needed to produce a scan. However, even with small laboratory sources it seemed possible to produce a usable scanner. This experimental scanner was constructed and developed to the stage of producing very acceptable images, albeit of moderate resolution. This thesis outlines the basic theory of reconstructing images using CT, and describes the considerations leading to the development of the experimental scanner. The scanner itself is described, along with details of control, data processing, and the problems encountered. The statistical limitations on the scanner are described, and the way these affect the quality of the final CT image is investigated in detail. A variety of applications of the scanner are suggested, both in its present form and with foreseeable development, and a catalogue of the scans obtained using the scanner is provided.

The Strain Index (SI) has repeatedly shown high levels of validity for differentiating between safe and hazardous tasks for the distal upper extremity (DUE). One limitation of the SI is the lack of reliability data. This study was designed to evaluate the test-retest repeatability of the SI. Fifteen raters, divided into five teams of three, were asked to use the SI to analyze 73 video AVI files of different job tasks; initially as individuals and then as teams. Several months later, raters were asked to repeat individual and team job task assessments. Raters were instructed to analyze tasks using five of six SI task variables, while the sixth was held constant. For three of these task variables, additional data was collected such as peak force and duration of job cycle. Test-retest repeatability was measured using Pearson's R, Spearman's rho, and tetrachoric correlation according to the nature of the variable. Spearman's rho values for individual and team task variable ratings ranged from 0.68 to 0.96 (0.88 average). Pearson's R for task variable data ranged from 0.76 to 0.99 for both teams and individuals with an average of 0.91. The Strain Index's rho values for individuals and teams were 0.70 and 0.84, respectively. For hazard classification, the tetrachoric correlation for individuals was 0.81 and 0.88 for teams. Results of this study support the conclusion that the Strain Index is repeatable when used by teams as well as individuals.

This thesis is related to varies statistical test of pseudorandom number generator. In thisthesis I have tried to discuss some aspects of selecting and testing Pseudorandom numbergenerators. The outputs of such generators may be used in many cryptographic applications,such as the generation of key material. After statistical test I have tried to compairethe test value of every generator and have discussed which one is producing good sequencesand which one is a good generator.

The overall aim of this thesis was to develop and validate a self-report instrument for perceived driver competence. The thesis includes six papers and a summary. All papers focus on perceived driver competence from a measurement perspective; that is, how to develop an instrument for perceived driver competence and how to use and interpret the scores from the instrument in a reliable and valid manner. Study I reviews how perceived driver competence has been measured in other studies and discusses these methods from a measurement perspective. Most studies have examined perceived driver competence by asking drivers to compare their own skill to that of the average driver. That method is problematic, since it is not possible to determine if drivers are overconfident or not, when empirical information of their own skills is missing. In order to examine if drivers overestimate their skills or not, perceived driver competence should be compared with actual driving performance. Study II reports on the development and psychometric evaluation of a self-report instrument for perceived driver competence - the Self-Efficacy Scale for Driver Competence (SSDC). The findings provides support for construct validity, as the SSDC demonstrated sound psychometric properties and as the internal structure of the SSDC corresponded to the theoretical model used as a basis for instrument development. In study III, the psychometric properties of the SSDC were further examined using an item response theory (IRT) model. The findings confirmed the results indicated by the classical analyses in Study II. Additional information was provided by the IRT analyses, as it was indicated that the scale would benefit from fewer scale points or by putting labels on each scale point. In study IV, Swedish and Finnish candidates’ self-assessment accuracy was examined by comparing candidates’ scores on the SSDC and a similar instrument for self-assessment of driving skill used in Finland, with driving test performance. Unlike previous studies, in which drivers compared their perceived skills to that of the average driver, a relatively large proportion made a realistic assessment of their own skills. In addition, in contrast to previous studies, no gender differences were found. These results were also confirmed in study V, where the results from the Finnish instrument for self-assessment of driving skill were compared with the results from a similar instrument used in the Netherlands. Study VI further examined the construct validity of a revised version of the SSDC, combining qualitative and quantitative sources of evidence. There was a strong relationship between the SSDC and an instrument for self-assessment of driving skills, providing support for convergent validity. No relationship was found between the SSDC and driving test performance. Explanations of the lack of relationship were provided from semi-structured interviews, as they indicated that confidence in performing different tasks in the test are different from being confident of passing the test, and that the candidates are familiar neither with assessing their own skills nor with the requirements for passing the test. In conclusion, the results from this thesis indicated that the choice of methods for assessing perceived driver competence as well as the quality of these methods affect the validity. The results provided support for different aspects of construct validity of the SSDC. Moreover, the findings illustrated the benefits of combining different methods in test validation, as each method contributed information about the validity of the SSDC. The studies in this thesis mainly examined internal and external aspects of construct validity. Future studies should examine procedural validity of the SSDC.

TiNi shape memory alloys (SMAs) have been extensively used in various applications. The great interest in TiNi alloys is due to its unique shape memory and superelasticity effects, along with its superior wear and dent resistance. Shape memory and superelastic effects are due to a reversible martensitic transformation that can be induced either thermally or mechanically. In this study, indentation tests at different temperatures, loads and strain rates have been performed on superelastic TiNi alloy. Deformation characteristics of superelastic TiNi under indentation have been compared to AISI 304 steel as a conventional material. Also, in-situ optical microscopy tests with interrupted heating have been employed in order to gain an insight into the coupled deformation and reversible martensitic transformation behaviour of TiNi SMAs under tensile loads. An understanding of the impacts of strain rate and temperature on the deformation behaviour of TiNi SMAs under localized compressive loads has been proposed.

No description available.

Tidigare forskning har varit oenig gällande vad ett SJT (situational judgment test) mäter. Studiens syfte är att undersöka vad SJT mäter genom att korrelera SJT-poängen med poängen på personlighets- respektive begåvningstest. Ytterligare en frågeställning är huruvida SJT skulle kunna vara ett användbart komplement till övriga arbetspsykologiska test. Totalt genomförde 130 personer fyra olika test; ett SJT, ett personlighetstest samt två begåvningstest (ett logiskt och ett matematiskt test). Resultatet av en regressionsanalys, med poängen på conscientiousness, agreeableness och g-faktorn som prediktorer av SJT-poäng, gav R = .31 och Adj R2 = .07. I linje med ett flertal andra studier blev conscientiousness och g-faktorn signifikanta prediktorer till SJT. Ytterligare studier krävs dock för att bekräfta vilket konstrukt SJT faktiskt mäter.