A Coalgebraic Semantics for Imperative Programming Languages

In the theory of programming languages, one often takes two complementary perspectives. In operational semantics, one defines and reasons about the behaviour of programs; and in denotational semantics, one abstracts away implementation details, and reasons about programs as mathematical objects or denotations. The denotational semantics should be compositional, meaning that denotations of programs are determined by the denotations of their parts. It should also be adequate with respect to operational equivalence: programs with the same denotation should be behaviourally indistinguishable. One often has to prove adequacy and compositionality independently for different languages, and the proofs are often laborious and repetitive. These proofs were provided systematically in the context of process algebras by the mathematical operational semantics framework of Turi and Plotkin – which represented transition systems as coalgebras, and program syntax by free algebras; operational specifications were given by distributive laws of syntax over behaviour. By framing the semantics on this abstract level, one derives denotational and operational semantics which are guaranteed to be adequate and compositional for a wide variety of examples. However, despite speculation on the possibility, it is hard to apply the framework to programming languages, because one obtains undesirably fine-grained behavioural equivalences, and unconventional notions of operational semantics. Moreover, the behaviour of these languages is often formalised in a different way – such as computational effects, which may be thought of as an interface between programs and external factors such as non-determinism or a variable store; and comodels, or transition systems which implement these effects. This thesis adapts the mathematical operational semantics framework to provide semantics for various classes of programming languages. After identifying the need for such an adaptation, we show how program behaviour may be characterised by final coalgebras in suitably order- enriched Kleisli categories. We define both operational and denotational semantics, first for languages with syntactic effects, and then for languages with effects and/or comodels given by a Lawvere theory. To ensure adequacy and compositionality, we define concrete and abstract operational rule-formats for these languages, based on the idea of evaluation-in-context; we give syntactic and then categorical proofs that those properties are guaranteed by operational specifications in these rule-formats.Open Acces

Implication des interactions plaquettes-neutrophiles dans la sécrétion des métalloprotéinases

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal

A Novel Approach for Performance Assessment of Human-Robotic Interaction

Robots have always been touted as powerful tools that could be used effectively in a number of applications ranging from automation to human-robot interaction. In order for such systems to operate adequately and safely in the real world, they must be able to perceive, and must have abilities of reasoning up to a certain level. Toward this end, performance evaluation metrics are used as important measures. This research work is intended to be a further step toward identifying common metrics for task-oriented human-robot interaction. We believe that within the context of human-robot interaction systems, both humans' and robots' actions and interactions (jointly and independently) can significantly affect the quality of the accomplished task. As such, our goal becomes that of providing a foundation upon which we can assess how well the human and the robot perform as a team. Thus, we propose a generic performance metric to assess the performance of the human-robot team, where one or more robots are involved. Sequential and parallel robot cooperation schemes with varying levels of task dependency are considered, and the proposed performance metric is augmented and extended to accommodate such scenarios. This is supported by some intuitively derived mathematical models and some advanced numerical simulations. To efficiently model such a metric, we propose a two-level fuzzy temporal model to evaluate and estimate the human trust in automation, while collaborating and interacting with robots and machines to complete some tasks. Trust modelling is critical, as it directly influences the interaction time that should be directly and indirectly dedicated toward interacting with the robot. Another fuzzy temporal model is also presented to evaluate the human reliability during interaction time. A significant amount of research work stipulates that system failures are due almost equally to humans as to machines, and therefore, assessing this factor in human-robot interaction systems is crucial. The proposed framework is based on the most recent research work in the areas of human-machine interaction and performance evaluation metrics. The fuzzy knowledge bases are further updated by implementing an application robotic platform where robots and users interact via semi-natural language to achieve tasks with varying levels of complexity and completion rates. User feedback is recorded and used to tune the knowledge base where needed. This work intends to serve as a foundation for further quantitative research to evaluate the performance of the human-robot teams in achievement of collective tasks

Rôle des Cellules Endothéliales Progénitrices dans la Régulation de la Fonction Plaquettaire

Les Cellules Endothéliales Progénitrices ("Endothelial Progenitor Cells", EPCs) sont des précurseurs endothéliaux qui jouent un rôle émergeant en biologie vasculaire. Les EPCs ont été localisées dans le cordon ombilical, la moelle osseuse, le sang périphérique et dans certains tissus régénérateurs. Les interactions des EPCs avec les cellules sanguines et vasculaires peuvent largement influencer leurs propriétés biologiques et dicter leur fonctionnement pendant la réparation endothéliale. Plus spécifiquement, les interactions des EPCs avec les plaquettes circulantes induisent leur migration, leur recrutement et leur différentiation en cellules endothéliales aux sites de lésions vasculaires. Cependant, l’impact d’une telle interaction sur la fonction plaquettaire n’a pas été recherché. Le but de mon projet était de :1) générer des EPCs à partir des cellules mononucléaires du sang humain périphérique ("Peripheral Blood Mononuclear Cells", PBMCs); 2) étudier les interactions adhésives entre les EPCs et les plaquettes; 3) déterminer leur impact sur la fonction plaquettaire et la formation du thrombus et 4) décrire le mécanisme d’action des EPCs sur les plaquettes et le thrombus. Mises en culture sur une surface de fibronectine dans un milieu conditionné, les PBMCs fraîchement isolées possédaient une morphologie ronde et une petite taille. Après cinq jours, les PBMCs adhérentes donnaient naissance à des colonies, puis formaient une monocouche de cellules aplaties caractéristiques des EPCs après dix jours de culture. Les EPCs différenciées étaient positives pour l’Ulex-lectine et l’Acétyle des lipoprotéines de faible densité ("Acetylated Low Density Lipoprotein", Ac-LDL), exprimaient les marqueurs progéniteurs (CD34, P-sélectine, VEGFR2, vWF et VE-Cadhérine) tandis que les marqueurs leucocytaires (CD14, PSGL-1 et L-sélectine) étaient absents. Ces EPCs interagissaient avec les plaquettes activées par un mécanisme dépendant de la P-sélectine plaquettaire, inhibaient l’activation et l’agrégation plaquettaire et réduisaient significativement l’adhésion plaquettaire, principalement par l’action de prostacycline (PGI2). En fait, ceci était associé avec une augmentation de l’expression de la cyclooxygénase-2 (COX-2) et du monoxyde d’azote (NO) synthéthase inductible (iNOS). Toutefois, les effets inhibiteurs des EPCs sur la fonction plaquettaire ont été renversés par une inhibition de la COX et non pas du NO. Bien que les EPCs fussent en mesure de lier les plaquettes via la P-sélectine, leurs effets prédominants étaient médiés essentiellement par une sécrétion paracrine, impliquant la PGI2. Néanmoins, un rapprochement étroit ou un bref contact entre les EPCs et les plaquettes était requis pour que cette fonction soit complètement réalisée. D’ailleurs, cet aspect a été investigué chez des souris déficientes en P-sélectine (P-sel-/-) et chez leurs congénères de phénotype sauvage (Wild Type, WT). Chez les souris WT, les EPCs inhibaient l’agrégation plaquettaire dans le sang complet de manière concentration-dépendante alors que dans les souris P-sel-/-, l’action des EPCs n’avait pas d’effet significatif. De plus, en utilisant un modèle murin de thrombose artérielle, nous avons démontré que l’infusion systémique des EPCs altéraient la formation du thrombus et réduisaient significativement sa masse chez les souris WT, mais non pas chez les souris P-sel-/-. En outre, le nombre des EPCs incorporées au niveau du thrombus et de la paroi vasculaire était visiblement réduit chez les P-sel-/- par rapport aux souris WT. Dans cette étude, nous sommes parvenus à différentier adéquatement des EPCs à partir des PBMCs, nous avons étudié les interactions adhésives entre les EPCs et les plaquettes, et nous avons décrit leur impact sur la fonction plaquettaire et la formation du thrombus. De plus, nous avons identifié la PGI2 comme étant le principal facteur soluble sécrété par les EPCs en culture et responsable de leurs effets inhibiteurs sur l’activation, l’adhésion et l’agrégation plaquettaire in vitro. De surcroît, nous avons élucidé le mécanisme d’action des EPCs sur l’agrégation plaquettaire et la formation du thrombus, in vivo, et nous avons souligné le rôle de la P-sélectine plaquettaire dans ce processus. Ces résultats ajoutent de nouvelles connaissances sur la biologie des EPCs et définissent leur rôle potentiel dans la régulation de la fonction plaquettaire et la thrombogenèse.Endothelial Progenitor Cells (EPCs) are believed to contribute to vascular biology and endothelial repair. EPCs have been isolated from umbilical cord, bone marrow, peripheral blood and in some regenerative tissues. Interactions of EPCs with vascular and blood cells can largely influence their functional properties and predict their destiny in the target tissues. More specifically, interactions of EPCs with circulating platelets provide the critical signal to ensure their migration and homing at the sites of vascular injury and their differentiation into endothelial cells. However, the functional consequences of such interactions on platelets remain unknown. Accordingly, this project was designed to investigate the impact of EPCs on platelet function and the specific objectives of this study were to: 1) generate EPCs from human peripheral blood mononuclear cells (PBMCs); 2) characterize the adhesive interactions between EPCs and platelets; 3) determine their impact on platelet function and thrombus formation and 4) elucidate the mechanistic action of EPCs on platelets and thrombus. Cultured on fibronectin in conditioned media, PBMCs differentiated, within ten days of culture, into EPCs, which were positive for Ulex-lectin and Ac-LDL (Acetylated Low Density Lipoprotein), and expressed progenitor markers (CD34, VEGFR2, vWF, and VE-Cadherin). These EPCs bind activated platelets through P-selectin-dependent mechanism, inhibited platelet activation, aggregation and adhesion, mainly via prostacyclin (PGI2) secretion. Indeed, this was associated with up-regulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide (NO) synthase (iNOS). However, the effects on platelets were reversed by COX, but not by NO inhibition. Although EPCs bound platelets via platelet P-selectin, their predominant effects occurred via a paracrine secretion, implying PGI2. Nevertheless, a transitory link or brief contact between EPCs and platelets was required for this function to be fully realized. This was further depicted using a murine arterial thrombosis model in P-selectin deficient mice (P sel-/-) and their wild-type counterparts (WT). EPCs significantly impaired, in a concentration dependent-manner, collagen-induced whole blood platelet aggregation in WT mice; whereas in P-sel-/- mice, EPCs had no significant effect. Moreover, in murin model of arterial thrombosis, infusion of EPCs altered thrombus formation and significantly reduced the mass of thrombi generated in WT, but not in P-sel-/- mice. Furthermore, the number of EPCs recruited within the thrombi and along the vascular wall was visually reduced in P-sel-/- mice as compared to WT mice. In this project, we succeeded in adequately differentiating EPCs from PBMCs, we characterized the adhesive interaction between EPCs and platelets, and we addressed the impact of EPCs on platelet function and thrombus formation. Moreover, we identified PGI2 as the principal soluble factor secreted by cultured EPCs and responsible of their inhibitory effects on platelet function in vitro. In addition, using a murine model of arterial carotid injury in WT and P-sel-/- mice, we elucidate the mechanistic action of EPCs on platelet aggregation and thrombus formation, in vivo, and we highlighted the role of platelet P-selectin in this process. These findings add new insights into the biology of EPCs and reveal a potential role for EPCs in regulating platelet function, which in turn may limit thrombogenesis and maintain hemostasis at the sites of vascular injury

Integrated Framework Design for Intelligent Human Machine Interaction

Human-computer interaction, sometimes referred to as Man-Machine Interaction, is a concept that emerged simultaneously with computers, or more generally machines. The methods by which humans have been interacting with computers have traveled a long way. New designs and technologies appear every day. However, computer systems and complex machines are often only technically successful, and most of the time users may find them confusing to use; thus, such systems are never used efficiently. Therefore, building sophisticated machines and robots is not the only thing someone has to address; in fact, more effort should be put to make these machines simpler for all kind of users, and generic enough to accommodate different types of environments. Thus, designing intelligent human computer interaction modules come to emerge. In this work, we aim to implement a generic framework (referred to as CIMF framework) that allows the user to control the synchronized and coordinated cooperative type of work that a set of robots can perform. Three robots are involved so far: Two manipulators and one mobile robot. The framework should be generic enough to be hardware independent and to allow the easy integration of new entities and modules. We also aim to implement the different building blocks for the intelligent manufacturing cell that communicates with the framework via the most intelligent and advanced human computer interaction techniques. Three techniques shall be addressed: Interface-, audio-, and visual-based type of interaction

Personality traits and political participation

The purpose of this study was to examine the Big Five personality traits in relation to political participation and activism at the American University in Cairo. Our hypothesis was that participants high on extraversion and openness to experience, and low on conscientiousness, agreeableness and neuroticism would be the most politically active. Questionnaires used to test this were the Big five Inventory (BFI), the Activism Orientation Scale (AOS), and a political participation questionnaire developed by our team. Convenience sampling was used to administer the questionnaires to our sample of 171 students. Results revealed positive correlations between extraversion and political participation, openness to experience and political participation, and openness to experience and activism. Also, it was found that higher neuroticism related to lower scores on the High-Risk activism sub scale

دراسة اقتصادية تحليلية لكفاءة استخدام أنماط الري الحديثة: دراسة ميدانية بمزارع منطقة القصيم

The study aims to estimate the efficiency of water resources use for irrigation at Al-Qassim farms by estimating the productivity and technical efficiency, under different irrigation methods (sprinkler and drip irrigation) used for the main crops which are included in the sample of study, and estimating the demand functions for resources used in the production of main crops. The analysis based on the Data Envelopment Analysis (DEA), in addition to Total Factor Productivity (TFP) and parametric programming. The DEA is used with the constant and variant returns to scale (CRS and VRS) to estimate the technical efficiency and scale efficiency of the considered crops under different irrigation methods. The study sample (consists of 124 farms) was selected from the farms at Al-Qassim region, Data collected by the personal interview through a questionnaire which was prepared for this purpose, the study sample were representative the most important field and vegetable crops at the study area. The most important findings of the study can summarize as follows: (1) By estimation the technical (TE) and scale efficiency (SE) for the field and vegetable crops at the study sample according to the concept of VRS and CRS under different irrigation methods, the results show the following: * According to CRS hypothesis the average technical efficiency (TE) under mobile sprinkler irrigation method were lower for farms of wheat, barley, winter tomatoes, corn, summer tomatoes and alfalfa, while results refers to improvement of (TE) for these crops according to VRS hypothesis. * The average of scale efficiency (SE), which is (SE=TECRS / TEVRS) amounted to about 0.91, 0.89, 0.90, 0.91, 0.90, 0.90 under the mobile sprinkler irrigation system for the farms of wheat, barley, winter tomatoes, corn, summer tomatoes and summer cucumber. * According to CRS hypothesis the average technical efficiency (TE) under drip irrigation method were lower for farms of zucchini, winter tomatoes, winter cucumber, summer potatoes, summer tomatoes and summer cucumbers, while results refers to improvement of (TE) for these crops according to VRS hypothesis. * The average of scale efficiency (SE), was to about 0.86, 0.94, 0.83, 0.94, 0.94, 0.86 under the drip irrigation system for the farms of zucchini, winter tomatoes, winter cucumber, summer potatoes, summer tomatoes and summer cucumber. (2) The change in the index of total factor productivity (TFP Ch) of the quantity of production for winter tomatoes and summer tomatoes as a shift from the mobile sprinkler system to the drip system about 119%, 112% and refers to an opportunity to increase efficiency by 19%, 12%, while the change in the index of total factor productivity (TFP Ch) of the value of production for alfalfa as a shift from the fixed sprinkler system to the mobile sprinkler system about 103%. (3) By estimating the production and economic efficiencies based on stochastic frontier Analysis (SFA) using the ordinary least square (OLS) method and the maximum likelihood estimator (MLE) method. The (MLE) method was used under both the Truncated Distribution (TD) and Half-Normal Distribution (HND) techniques. The results indicated to the preference of MLE method in case of (HND) according to significance of γ to estimate the production efficiency of wheat, zucchini and alfalfa. While MLE method in case of (TD) according to significance of γ and the highest value of the LR was the best for crops winter and summer tomatoes, and winter and summer cucumbers. The OLS method was the fit to estimate the production efficiency of barley, corn and summer potatoes. (4) Using the parametric programming to identify the value of the marginal productivity (shadow prices) for each of the nitrogenous, phosphate fertilizers, agricultural employment and water resources. The results indicated that the shadow price of the unit (50 kg) for the resource of phosphate fertilizer up to about 69.1 SAR at the optimal use of the resource in the production of winter crops which follows the mobile sprinkler irrigation system, while up to about 131.3 SAR at the optimal use of the resource in the production of summer crops. For the resource of nitrogenous fertilizers used in the production of winter crops which follows the mobile sprinkler irrigation system, the shadow price of the unit (50 kg) up to about 295.4 SAR and up to about 68.7 SAR for the summer crops. For the labor resource used in the production of winter crops which follows the mobile sprinkler irrigation system, the shadow price of the unit (man / day) is approximately 52.3 SAR at the optimum utilization of the resource, while up to about 47.5 SAR to produce the summer crops

ARTIFICIAL INTELLIGENCE FOR AUTHENTICATION THROUGH MENTAL PROFILING TECHNIQUE

A new approach to user authentication using mental profiling saw light, which is a technique that involves measuring an individual\u27s cognitive abilities and psychological traits to create a unique profile, using Artificial Intelligence techniques. These profiles can then be used to identify users securely and efficiently, even in the presence of sophisticated attacks, by harnessing AI-driven systems for mental profile creation and user authentication. After reviewing the existing literature on authentication and mental profiling, it presents a new mental profiling test that is specifically designed for authentication purposes. The test was evaluated on a sample of 100 users, and results showed that it is able to accurately identify users with a high degree of confidence. Mental profiling opens doors to deeper insights into the cognitive and psychological factors that make each individual unique, paving the way for interventions that can enhance human performance and well-being with the usage of Artificial Intelligence tools

Antenna selection and performance analysis of MIMO spatial multiplexing systems

Multiple-input multiple-output spatial multiplexing (MIMO-SM) systems offer an essential benefit referred to as spatial multiplexing gain. Two important signal reception techniques for MIMO-SM systems are the zero-forcing (ZF) and ordered successive interference cancellation (OSIC) as, for example, in the case of the decision-feedback detector (DFD). This thesis studies the communication and signal processing aspects of MIMO-SM. We first investigate the bit error rate (BER) performance of the ZF receiver over transmit correlated Ricean flat-fading channels. In particular, for a MIMO channel with M transmit and N receive antennas, we derive an approximation for the average BER of each sub-stream. A closed-form expression for the optimal transmit correlation coefficient, which achieves the maximum capacity (i.e., uncorrelated case) of two-input two-output spatial multiplexing (TITO-SM) systems, is presented. We further propose an antenna selection (AS) approach for the DFD over independent Rayleigh flat-fading channels. The selected transmit antennas are those that maximize both the post-processing signal-to-noise ratio (SNR) at the receiver end, and the system capacity. An upper bound on the outage probability for the AS approach is derived. It is shown that the AS approach achieves a performance comparable to optimal capacity-based selection based on exhaustive search, but at a lower complexity. Finally, we investigate a cross-layer transmit AS approach for the DFD over spatially correlated Ricean flat-fading channels. The selected transmit antennas are those that maximize the link layer throughput of correlated MIMO channels. A closed-form expression for the system throughput with perfect channel estimation is first derived. We further analyze the system performance with pilot-aided channel estimation. In that, we derive a closed-form expression for the post-detection signal-to-noise-plus-interference ratio (SNIR) of each transmitted substream, conditioned on the estimated channels. The derived SNIR is then used to evaluate the overall system throughput. It is observed that the cross-layer AS approach always assigns the transmission to the antenna combination which sees better channel conditions, resulting in a substantial improvement over the optimal capacity-based AS approach. Considering a training-based channel estimation technique, we compare the performance of the proposed cross-layer AS with that of optimal capacity-based AS when employed with a training-based channel estimation. Our results show that the latter is more robust to imperfect channel estimation. However, in all cases, the cross-layer AS delivers higher throughput gains than the capacity-based A