En esta tesis se estudió el fraccionamiento de aceites esenciales obtenidos de plantas aromáticas comunes en el país mediante el uso de dióxido de carbono supercrítico, con el objetivo de obtener compuestos o fracciones con actividad biocida. Se seleccionaron tres plantas: Tagetes minuta, Salvia officinalis y Mentha piperita. La extracción del aceite esencial se realizó mediante hidrodestilación, determinándose su composición mediante cromatografía de gases. Como parte de esta tesis, se construyó un equipo experimental de alta presión, con el cual se realizaron mediciones de solubilidad y composición de la fase supercrítica para cada sistema [CO2 + aceite esencial] en distintas condiciones de presión y temperatura (70–120 bar, 313–323 K), utilizando el método dinámico o de gas saturado. Se realizaron también ensayos de fraccionamiento semicontinuo para determinar la influencia de la composición en el grado de separación. Con los resultados experimentales obtenidos se validó un modelo termodinámico predictivo basado en la ecuación de estado a contribución grupal (GC-EOS), previo ajuste de los parámetros necesarios con datos provenientes de otras fuentes. Utilizando dicho modelo como base, y reduciendo la complejidad de los sistemas en términos de dos o tres pseudo-componentes, se realizaron simulaciones de columnas de fraccionamiento de múltiples etapas en contra-corriente, analizando la influencia de las variables operativas (presión, temperatura, relación solvente/ alimentación, relación de reflujo, etc.) con el objetivo de hallar condiciones recomendables de operación para separar los compuestos biocidas de interés. En el análisis, se utilizaron herramientas y consideraciones de la Ingeniería del Equilibrio de Fases. En el caso del aceite de T. minuta se procuró separar la fracción de cetonas insaturadas (ocimenonas); en el caso del aceite de S. officinalis se planteó la purificación de la fracción de monoterpenos oxigenados, separándolos a la vez de los hidrocarburos y de los sesquiterpenos; en el caso del aceite de M. piperita se planteó la separación de mentona y mentol. La actividad biocida de las fracciones obtenidas experimentalmente a partir del aceite de T. minuta fueron ensayadas frente a dos parásitos: el gorgojo del maíz y el nemátodo del nudo de la raíz. / The fractionation of essential oils from local aromatic species using supercritical carbon dioxide was studied, in order to obtain compounds or fractions with biocidal activity. Three species were chosen: Tagetes minuta, Salvia officinalis y Mentha piperita. The essential oil was extracted by hydrodistillation and its composition determined by gas chromatography. As a part of this project, a lab-scale high-pressure experimental apparatus was built. With this equipment, measurements of solubility and composition in the supercritical phase were performed for each [CO2 + essential oil] system at different pressure and temperature conditions (70–120 bar, 313–323 K), using a dynamic or gas saturated method. Semi-continuous fractionation experiments were also carried out in order to determine the effect of composition in the separation performance. With the experimental data a predictive thermodynamic model based on the group contribution equation of state (GC-EOS) was validated, after fitting the necessary parameters with data from other sources. With this model as background, and reducing the systems complexity in terms of two or three pseudo-components, simulations of multistage counter-current columns were carried out, analyzing the influence of the operation parameters (pressure, temperature, solvent-to-feed ratio, reflux ratio, etc.), in order to find recommended conditions for the separation of the biocidal components. In this analysis, phase equilibrium engineering tools and considerations were applied. In the case of T. minuta, the goal was to isolate the unsaturated ketones fraction (ocimenones); in the case of S. officinalis the goal was the separation of the oxygenated monoterpenes fraction from both the hydrocarbon and the sesquiterpene fraction; finally in the case of M. piperita the separation between menthone and menthol was proposed. The biocidal activity of the fractions obtained experimentally from T. minuta oil was tested against the corn weevil and the root knot nemathod.

Yes / Carbon capture and storage (CCS) has attracted renewed interest in the re-evaluation of the equations of state (EoS) for the prediction of thermodynamic properties. This study also evaluates EoS for Peng–Robinson (PR) and Soave–Redlich–Kwong (SRK) and their capability to predict the thermodynamic properties of CO2-rich mixtures. The investigation was carried out using machine learning such as an artificial neural network (ANN) and a classified learner. A lower average absolute relative deviation (AARD) of 7.46% was obtained for the PR in comparison with SRK (AARD = 15.0%) for three components system of CO2 with N2 and CH4. Moreover, it was found to be 13.5% for PR and 19.50% for SRK in the five components’ (CO2 with N2, CH4, Ar, and O2) case. In addition, applying machine learning provided promise and valuable insight to deal with engineering problems. The implementation of machine learning in conjunction with EoS led to getting lower predictive AARD in contrast to EoS. An of AARD 2.81% was achieved for the three components and 12.2% for the respective five components mixture.

No description available.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / There are well-known advantages in using pseudo-random sequences for testing of data communication links. The sequences, also called pseudo-noise (PN) sequences, approximate random data very well, especially for sequences thousands of bits long. They are easy to generate and are widely used for bit error rate testing because it is easy to synchronize a slave pattern generator to a received PN stream for bit-by-bit comparison. There are other aspects of PN sequences, however, that are not as widely known or applied. This paper points out how some of the less familiar characteristics of PN sequences can be put to practical use in the design of a Digital Test Set and other specialbuilt test equipment used for checkout of the EOS AM-1 Space Data Receiver. The paper also shows how knowledge of these PN sequence characteristics can simplify troubleshooting the digital sections in the Space Data Receiver. Finally, the paper addresses the sufficiency of PN data testing in characterizing the performance of a receiver/data recovery system.

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

: la schizophrénie à début précoce (SDP) est un syndrome rare invalidant peu étudié. Dans ce travail, nos objectifs sont: de caractériser de profils cliniques des SDP via une approche développementale et dimensionnelle; de poser un diagnostic étiologique des formes organiques; d'analyser la reconnaissance émotionnelle dans la SDP. Méthodologie: Dans une cohorte d'enfants atteints de SDP (N=90) j'ai développé et validé une méthode de psychométrie quantitative en utilisant une échelle spécifique Lifetime Dimensions of Psychosis Scale - Children and Adolescents; des données de psychologie expérimentale; de génétique. Résultats: en appliquant une évaluation développementale et dimensionnelle, j'ai identifié 6 profils cliniques dans la cohorte SDP. L'analyse par clusters retrouve 3 groupes, dont le cluster plus significatif est caractérisé par une sévérité importante des symptômes positifs et de ceux positifs bizarres. Ce cluster montre une association modérée entre la sévérité des symptômes positifs bizarres et les anomalies du développement. Dans une perspective étiologique des SDP, j'ai proposé une série d'explorations médicales de premier rang afin d'éliminer une SDP organique. J'ai décrit le cas clinique d'un patient porteur d'une délétion de 1,9 Mb dans la région 8p23.2 qui pourrait entrainer une perte de fonction du gène CSMD1, dont la protéine est impliquée dans la régulation immunitaire du développement cérébral. J'ai intégré à ce travail une étude de psychologie expérimentale appliquée à la SDP. Cette étude est la première à avoir exploré le rôle de l'intégration multi-sensorielle dans la reconnaissance émotionnelle dans une perspective développementale chez des patients atteints de SDP. Conclusion: la SDP est un trouble cliniquement hétérogène dont l’étiologie est inconnue et dont la compréhension des différents mécanismes physiopathologiques pourrait contribuer à des nouvelles stratégies thérapeutiques. / Early Onset Schizophrenia (EOS) is a severe but rare disorder in children. Focusing on developmental pathways to EOS, this work aims: to describe different developmental profiles that contribute to EOS phenotypes using a dimensional perspective; to study medical conditions associated with EOS using multidisciplinary search; to assess emotional recognition as key factor of social interaction. Methods: In a cohort of 90 children with EOS, I applied quantitative psychometric methods with development and validation of a specific scale; experimental psychology; molecular cytogenetics. Results: using a dimensional and developmental evaluation (Lifetime Dimensions of Psychosis Scale – Children Adolescents), I identified symptom profiles. In EOS cohort, 6 dimensional factors were identified. 64% of sample had premorbid developmental or learning problems. Cluster analysis delineated 3 groups: the largest cluster including 58% of the patients was characterized by high Positive and Bizarre Positive scores and fewer (28%) developmental abnormalities. I also reviewed numerous likely organic causalities in EOS. I proposed a systematic algorithm to better assess these conditions by focusing on treatable ones. I detailed a case report on an adolescent with EOS carrier of a rare CNV implicated in the immune modulation of cerebral pruning. Assessing emotional recognition, empathy development and non verbal communication, I found that EOS patients performed worse than healthy controls in emotional tasks, with a significant association between emotional identification scores and nonverbal communication impairments. This means that cumulative dysfunctions in both nonverbal communication and emotion processing contribute to the social vulnerability found in youths with EOS. Conclusion: EOS is a complex condition with unknown etiology. How the understanding of specific etiologies may lead to new therapeutic approaches is the next challenge.

No description available.

Το αντικείμενο της εργασίας αυτής είναι η μελέτη των μετανευτώνειων προσεγγίσεων στο πλαίσιο της Γενικής Σχετικότητας, με έμφαση στους αστέρες νετρονίων. Λόγω του οτι, η μελέτη των αστέρων νετρονίων βασίζεται στην υδροδυναμική περιγραφή της ύλης, το κύριο ενδιαφέρον μας αφορά στον τρόπο που εισάγονται οι μετανευτώνειες προσεγγίσεις στις υδροδυναμικές εξισώσεις της Γενικής Σχετικότητας. Στο πρώτο κεφάλαιο παρουσιάζονται ορισμένα θεωρητικά στοιχεία γύρω απο φυσικά χαρακτηριστικά και τις ιδιότητες των συμπαγών αστέρων. Στο δεύτερο κεφάλαιο παρουσιάζονται τα γενικά χαρακτηριστικά των καταστατικών εξισώσεων των συμπαγών αστέρων, με έμφαση στην πολυτροπική καταστατική εξίσωση. Στο τρίτο κεφάλαιο παρουσιάζεται η θεωρία των μετανευτώνειων προσεγγίσεων, καθώς και οι μετανευτώνειες εξισώσεις πρώτης τάξης της υδροδυναμικής, στη Γενική Σχετικότητα όπως εισήχθησαν απο τον Chandrasekhar. Στο τέταρτο κεφάλαιο παρουσιάζεται η διαταρακτική μέθοδος που χρησιμοποιείται απο τους Fahlman και Anand, για την μελέτη των περιστρεφόμενων πολυτρόπων στο πλαίσιο της πρώτης μετανευτώνειας προσέγγισης στη Γενική Σχετικότητα. Στο πέμπτο κεφάλαιο παρουσιάζεται η μετανευτώνεια προσέγγιση δεύτερης τάξης όπως διατυπώθηκε απο τους Chandrasekhar και Nutku. Στο έκτο, και τελευταίο, κεφάλαιο παρουσιάζεται ένα υπολογιστικό αλγεβρικό πακέτο για μετανευτώνειους υπολογισμούς στη Γενική Σχετικότητα, το PROCRUSTES. Με την βοήθεια του πακέτου αυτού υπολογίσαμε διάφορες ποσότητες στη δεύτερη μετανευτώνεια προσέγγιση, όπως τον τανυστή ενέργειας - ορμής, 𝑇𝑖𝑗, τον τανυστή Ricci, 𝑅𝑖𝑗, τις εξισώσεις κίνησης, Τ𝑖𝑗;𝑗 = 0, και άλλες. Το PROCRUSTES είναι ένα πολύ χρήσιμο εργαλείο στη μετανευτώνεια μελέτη καθώς μπορεί κανείς να παράξει τις περίπλοκες εκφράσεις διαφόρων ποσοτήτων σε ελάχιστο χρόνο και χωρίς την πιθανότητα λάθους. Επίσης, με την βοήθεια του πακέτου αυτού, υπολογίσαμε τις αναλυτικές εκφράσεις των εξισώσεως κίνησης, Τ𝑖𝑗;𝑗 = 0, στην δεύτερη μετανευτώνεια προσέγγιση. Με κατάλληλη μετατροπή των εκφράσεων αυτών, μπορούμε να εφαρμόσουμε την μέθοδο των Fahlman και Anand, με σκοπό την μελέτη των περιστερόμενων πολυτρόπων στη μετανευτώνεια προσέγγιση δεύτερης τάξης. Στο τέλος της εργασίας παρατίθεται ένα συμπλήρωμα με τη δομή του προγράμματος και ορισμένες απο τις ποσότητες που υπολογίστηκαν στο πλαίσιο της εργασίας. / The main subject of my master thesis is the study of,the post-Newtonian approximations (PNA) in General Relativity (G-R), mainly those that concern the neutron stars. Owing to the study of neutron stars is on the hydrodynamic description of matter, our main interest lies uponthe way the PNA affects the hydrodynamic equations of G-R. In the first chapter there is presented the main theory around the physical attributes of compact stars. The second chapter reffers to the general features of the equations of state (EoS) of compact stars, giving emphasis to the polytropic EoS. In the yhird chapter, there is presented the theory of the PNA. There are also presented the the hydrodynamic equations in the PNA as the were introduced by Chandrasekhar. The fourth chapter is dedicated to the presentation of the method that was introduced by Fahlman and Anand, on the study of rotating polytropes in the PNA to G-R. The fifth chapter focuses on the second PNA as it formulated by Chandrasekhar and Nutku. During the sixth and final chapter there is presented a computer algebra package for post-Newtonian calculations in G-R, the PROCRUSTES. Whith the aid of thiw package, we calculated several quantities in the second PNA, as for example the E-M tensor 𝑇𝑖𝑗„ the Ricci tensor 𝑅𝑖𝑗 and the equations of motion (EoM) Τ𝑖𝑗 ;𝑗 = 0. PROCRUSTES is a very useful tool for the post-Newtonian study, as someone can produce the compicated equations of several quantities in no time and eliminating the possibility of making some mistake during the calculation. Moreover, using PROCRUSTES we calculated the expressions of the EoM’s in the second PNA. Under appropriate transformation of these expressions, we are able to apply the method of Fahlman and Anand onto these equations with a view to the study of rotating polytropes in the second PNA. At the end of this work there is quoted a supplement with the structure of the programm we used, along with some of the quantities that were calculated during this work.

L'ostéoporose est une maladie du squelette caractérisée par une perte de la qualité osseuse qui entraîne un risque de fracture accru, notamment au niveau vertébral. Des modèles en éléments finis basés sur la tomodensitométrie permettent d'estimer la résistance vertébrale, et donc le risque de fracture, mais leur utilisation en routine clinique est limitée par le coût et l'irradiation engendrée par la tomodensitométrie. L'estimation la résistance vertébrale à partir d'un modèle en éléments finis basés sur l'imagerie basse dose, telle que l'absorptiométrie biphotonique à rayons X, ou la stéréo-radiographie EOS en double énergie, permettrait une utilisation en routine clinique. Cette thèse contribue au développement de la modélisation à partir de l'imagerie basse dose pour la prédiction du risque de fracture. Un modèle en éléments finis de résistance vertébrale y est évalué par rapport à un modèle basé sur la tomodensitométrie, et une étude de sensibilité identifie les facteurs importants du modèle sont analysés. Des méthodes de maillage hexaédrique morpho-réalistes à partir de la reconstruction 3D, et d'estimation de la distribution de densité à partir d'image 2D de densité y sont développées. De plus, profitant des possibilités du système EOS qui permet de radiographier le patient de la tête aux pieds, une méthode préliminaire est proposée pour estimer l'effort exercé sur les vertèbres in vivo. Nous espérons que nos méthodes pourront être utilisées très prochainement in vivo, et contribuer à l'estimation du risque de fracture ostéoporotique, et à la prise en charge des patients à risque de fracture.

The Unconventional Resource Plays consisting of the lowest tier of resources (large volumes and most difficult to develop) have been the main focus of US domestic activity during recent times. Horizontal well drilling and hydraulic fracturing completion technology have been primarily responsible for this paradigm shift. The concept of drainage volume is being examined using pressure diffusion along streamlines. We use diffusive time of flight to optimize the number of hydraulic fracture stages in horizontal well application for Tight Gas reservoirs. Numerous field case histories are available in literature for optimizing number of hydraulic fracture stages, although the conclusions are case specific. In contrast, a general method is being presented that can be used to augment field experiments necessary to optimize the number of hydraulic fracture stages. The optimization results for the tight gas example are in line with the results from economic analysis. The fluid flow simulation for Naturally Fractured Reservoirs (NFR) is performed by Dual-Permeability or Dual-Porosity formulations. Microseismic data from Barnett Shale well is used to characterize the hydraulic fracture geometry. Sensitivity analysis, uncertainty assessment, manual & computer assisted history matching are integrated to develop a comprehensive workflow for building reliable reservoir simulation models. We demonstrate that incorporating proper physics of flow is the first step in building reliable reservoir simulation models. Lack of proper physics often leads to unreasonable reservoir parameter estimates. The workflow demonstrates reduced non-uniqueness for the inverse history matching problem. The behavior of near-critical fluids in Liquid Rich Shale plays defies the production behavior observed in conventional reservoir systems. In conventional reservoirs an increased gas-oil ratio is observed as flowing bottom-hole pressure is less than the saturation pressure. The production behavior is examined by building a compositional simulation model on an Eagle Ford well. Extremely high pressure drop along the multiple transverse hydraulic fractures and high critical gas saturation are responsible for this production behavior. Integrating pore-scale flow modeling (such as Lattice Boltzmann) to the field-scale reservoir simulation may enable quantifying the effects of high capillary pressure and phase behavior alteration due to confinement in the nano-pore system.