In spite of the SAPS having a dedicated polygraph capacity since 1998, little research has been conducted with regard to the use of the polygraph in criminal investigations. Consequently, the aim of this research was to focus on the perceptions and experiences of investigators in the SAPS regarding the application of polygraph testing in criminal investigations, the application of the polygraph as an investigative aid, the extent to which it is used by SAPS investigators to resolve criminal cases opened by the general public and/or in internal departmental criminal investigations; and whether or not it has helped to solve cases by giving direction and/or focus to the investigator when an investigation is at an impasse. A qualitative research approach was conducted among investigators within the SAPS. The research design selected for this study was grounded theory. The sample consisted of twenty investigators, ten of whom had previously used polygraph examinations in their investigations and ten of whom had not. Data was collected from interviews, document analysis, field notes and memoranda which presented and detailed the perceptions and experiences of investigators in the SAPS regarding the application of polygraph tests in criminal investigations. / Criminology and Security Science / M.A. (Criminology)

This research was an investigation of three domains identified through a thorough review of the literature as fundamental to the equitable implementation of Response to Intervention (RtI) with English language learners (ELLs): (1) degree of intercultural sensitivity of educators involved in the RtI process, (2) training of educators in implementation of RtI with ELLs, and (3) educator familiarity with empirically-based interventions for use with ELLs. The validity of using RtI with ELLs has been questioned by both supporters and detractors of the model (Linan-Thompson & Ortiz, 2009). The most fundamental tenets of RtI are predicated upon the use of empirically validated interventions and the application of culturally responsive educational practices that provide equitable learning opportunities for all students. Due to the critical role of school psychologists in the development and implementation of RtI models, a questionnaire was designed for use with this population to explore the three domains delineated above. The Intercultural Sensitivity Scale (ISS; Chen & Starosta, 2000) was used to document participants' degree of intercultural sensitivity. Additional questions addressing domains two and three strategically juxtaposed participants' experiences with and perceptions regarding RtI with native English speakers versus RtI with ELLs. Through a series of eight research questions and the associated analyses, the following conclusions were reached: (1) Statistically significantly higher mean scores on the ISS were present among those respondents who identified themselves as Hispanic/Latino/Spanish and/or fluent in more than one language; (2) Statistically significant differences were documented in participants' responses to items focused on perceptions of training for implementing RtI with native English speakers versus training for implementing RtI with ELLs; and (3) Statistically significant differences were found in participants' responses to items inquiring about perceptions of familiarity with empirically-based interventions for use within an RtI framework with native English speakers in comparison to ELLs. Taken together, and in conjunction with a qualitative analysis of two open-ended questions, these results suggest the presence of considerable delays in school psychologists' training and perceptions of preparedness to implement RtI with a linguistically diverse population as compared to native English speakers. This outcome is disconcerting, given the emphasis throughout the literature on the importance of unique considerations required to implement RtI equitably with ELLs. Recommendations for practice and future research are provided that emphasize the need for additional research and training in implementing RtI with a linguistically diverse population.

Synchronous languages such as Signal, Lustre and Esterel are dedicated to designing safety-critical systems. Their compilers are large and complicated programs that may be incorrect in some contexts, which might produce silently bad compiled code when compiling source programs. The bad compiled code can invalidate the safety properties that are guaranteed on the source programs by applying formal methods. Adopting the translation validation approach, this thesis aims at formally proving the correctness of the highly optimizing and industrial Signal compiler. The correctness proof represents both source program and compiled code in a common semantic framework, then formalizes a relation between the source program and its compiled code to express that the semantics of the source program are preserved in the compiled code.

Les langages synchrones tels que Signal, Lustre et Esterel sont dédiés à la conception de systèmes critiques. Leurs compilateurs, qui sont de très gros programmes complexes, peuvent a priori se révéler incorrects dans certains situations, ce qui donnerait lieu alors à des résultats de compilation erronés non détectés. Ces codes fautifs peuvent invalider des propriétés de sûreté qui ont été prouvées en appliquant des méthodes formelles sur les programmes sources. En adoptant une approche de validation de la traduction, cette thèse vise à prouver formellement la correction d'un compilateur optimisé et industriel de Signal. La preuve de correction représente dans un cadre sémantique commun le programme source et le code compilé, et formalise une relation entre eux pour exprimer la préservation des sémantiques du programme source dans le code compilé. / Synchronous languages such as Signal, Lustre and Esterel are dedicated to designing safety-critical systems. Their compilers are large and complicated programs that may be incorrect in some contexts, which might produce silently bad compiled code when compiling source programs. The bad compiled code can invalidate the safety properties that are guaranteed on the source programs by applying formal methods. Adopting the translation validation approach, this thesis aims at formally proving the correctness of the highly optimizing and industrial Signal compiler. The correctness proof represents both source program and compiled code in a common semantic framework, then formalizes a relation between the source program and its compiled code to express that the semantics of the source program are preserved in the compiled code.

Quand on veut évaluer ou manipuler une fonction mathématique f, il est fréquent de la remplacer par une approximation polynomiale p. On le fait, par exemple, pour implanter des fonctions élémentaires en machine, pour la quadrature ou la résolution d'équations différentielles ordinaires (ODE). De nombreuses méthodes numériques existent pour l'ensemble de ces questions et nous nous proposons de les aborder dans le cadre du calcul rigoureux, au sein duquel on exige des garanties sur la précision des résultats, tant pour l'erreur de méthode que l'erreur d'arrondi.Une approximation polynomiale rigoureuse (RPA) pour une fonction f définie sur un intervalle [a,b], est un couple (P, Delta) formé par un polynôme P et un intervalle Delta, tel que f(x)-P(x) appartienne à Delta pour tout x dans [a,b].Dans ce travail, nous analysons et introduisons plusieurs procédés de calcul de RPAs dans le cas de fonctions univariées. Nous analysons et raffinons une approche existante à base de développements de Taylor.Puis nous les remplaçons par des approximants plus fins, tels que les polynômes minimax, les séries tronquées de Chebyshev ou les interpolants de Chebyshev.Nous présentons aussi plusieurs applications: une relative à l'implantation de fonctions standard dans une bibliothèque mathématique (libm), une portant sur le calcul de développements tronqués en séries de Chebyshev de solutions d'ODE linéaires à coefficients polynômiaux et, enfin, un processus automatique d'évaluation de fonction à précision garantie sur une puce reconfigurable. / For purposes of evaluation and manipulation, mathematical functions f are commonly replaced by approximation polynomials p. Examples include floating-point implementations of elementary functions, integration, ordinary differential equations (ODE) solving. For that, a wide range of numerical methods exists. We consider the application of such methods in the context of rigorous computing, where we need guarantees on the accuracy of the result, with respect to both the truncation and rounding errors.A rigorous polynomial approximation (RPA) for a function f defined over an interval [a,b] is a couple (P, Delta) where P is a polynomial and Delta is an interval such that f(x)-P(x) belongs to Delta, for all x in [a,b]. In this work we analyse and bring forth several ways of obtaining RPAs for univariate functions. Firstly, we analyse and refine an existing approach based on Taylor expansions. Secondly, we replace them with better approximations such as minimax approximations, Chebyshev truncated series or interpolation polynomials.Several applications are presented: one from standard functions implementation in mathematical libraries (libm), another regarding the computation of Chebyshev series expansions solutions of linear ODEs with polynomial coefficients, and finally an automatic process for function evaluation with guaranteed accuracy in reconfigurable hardware.

Telemetry system, Optimisation, Sensoric networks, Smart Grid, Internet of Things, Sensors, Information security, Cryptography, Cryptography algorithms, Cryptosystem, Confidentiality, Integrity, Authentication, Data freshness, Non-Repudiation.