The physiological signals of human are very important for the diagnosis of diseases. There are two different applications of physiological signals in this study. One is using oxyhemoglobin saturation to diagnose the obstructive sleep apnea hypopnea syndrome (OSAS); the other is to determine the association between dermatoglyphics and schizophrenia by using fingerprint asymmetry measures. The objective of the first part is to comprehensively evaluate the capablity and reliability of the previously proposed oxyhemoglobin indices derived automatically for predicting the severity of OSAS. Patients with a diagnosis of OSAS by standard polysomnography were recruited from China Medical University Hospital Sleep Center. The result revealed that when AHI cutoff value was set to 30/h, ODI achieves 87.8% sensitivity and 96.6% specificity. Another important finding is that, for both apnea and hypopnea, probability of oxyhemoglobin desaturation increases with increases of body mass index (BMI) and neck circumference (NC). Early detection and intervention strategies for schizophrenia are receiving increasingly more attention. Dermatoglyphic patterns have been hypothesized to be indirect measures for early abnormal developmental processes that can lead to later psychiatric disorders such as schizophrenia. However, previous results have been inconsistent in trying to establish the association between dermatoglyphics and schizophrenia. The goal of second part of this work is to try to resolve this problem by borrowing well developed techniques from the field of fingerprint matching. Fingerprint images were acquired digitally from 40 schizophrenic patients and 51 normal individuals. Based on these images, the sample means of the proposed measures consistently identified the patient group as having a higher degree of asymmetry than the control group.

Thesis (Ph. D.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xxi, 280 p. : ill. (some col.), maps. Vita. Includes abstract. Includes bibliographical references (p. 150-152).

The efficiency of one fluid displacing another in permeable media depends greatly on the pore-scale dynamics at the main wetting front. Experiments have shown that the frontal dynamics can result in two different flow regimes: a stable and an unstable front. In stable displacements, any perturbation of the front will diminish with time and the effect of variation in permeability will be lessened. In contrast, in unstable displacements any perturbation of the front will grow with time and any variation in permeability will be magnified. In this dissertation, the stability of two different displacement processes are contemplated; a) vertical infiltration of dense liquid into dry sand from above and b) horizontal displacement of nanoparticle suspension with high pressure liquid CO₂. Significant insights are obtained by measuring the in-situ flow patterns in real time with a light transmission method and CT scanning. Vertical infiltration of dense fluid into dry sands from above is often observed to be unstable and produce gravity driven fingers. The formation of gravity fingers can have large consequences on the sweep efficiency of a displacement. Infiltration experiments showed that gravity driven fingers have a unique saturation profile known as saturation overshoot with a higher saturation at the finger tips than the saturation at the finger tail. Despite the vast number of theoretical and experimental investigations, conditions under which the front is unstable, remain unclear. To determine what controls the saturation overshoot and how it relates to the dynamics at the initial wetting front, saturation overshoot was measured as a function of flux for seven different liquids. These liquids gave a range of molecular weights, viscosities, and vapor pressures. It is found that for each fluid there is a flux (called overshoot flux) below which saturation overshoot ceases and the front is diffuse. The magnitude of the overshoot flux depends inversely on the invading fluid's viscosity and shows little or no dependence on the invading fluid's surface tension, vapor pressure, or miscibility with water. Since the saturation overshoot is not described by the continuum multi-phase flow models, the experimental results are used to develop a semi-continuum model that bridges the continuum-scale and pore-scale physics. The proposed model predicts the observed dependence of overshoot on media permeability and invading fluid properties. At the planned depth for CO₂ injection, either as an enhanced oil recovery technique or for CO₂ storage, CO₂ is typically less dense and less viscous than the in-situ fluid. Therefore, CO₂ injection is unstable and produces viscous fingers. This can greatly reduce the efficiency of a CO₂ flood or CO₂ storage capacity of an aquifer. To remedy this behavior, surface treated nanoparticles were used to reduce the mobility of injected CO₂. Displacement experiments were performed at low pressure with a CO₂ analogue (n-octane) fluid and at high pressure with liquid CO₂. Saturation distributions and pressure drops were measured in real time with the CT scanner when high pressure liquid CO₂ or n-octane was used to displace brine in different cores with and without suspended nanoparticles. In the presence of nanoparticles, the displacement front is more spatially uniform with a later breakthrough compared to the same experiment with no suspended nanoparticles. These observations suggest that nanoparticle stabilized foam, which forms during the displacement, acts to suppress the instability. It is argued that the generation of droplets occurs at the leading front of all drainage displacements. In the presence of nanoparticles, these droplets are preserved when nanoparticle adhere at the fluid-fluid interface. The new mechanism for foam generation described here, provides an interesting alternative for mobility control in CO₂ floods. Moreover, the same mechanism can potentially a) increase the CO₂ storage capacity of an aquifer, b) enhance the CO₂ capillary trapping, and c) provide an engineered barrier to CO₂ leakage from a storage sites, thereby alleviating the risk of contaminating the overlying fresh groundwater resources for CO₂ storage projects. / text

Στη διπλωματική αυτή περιγράφεται η κατασκευή ενός σφυγμοξύμετρου, της ιατρικής συσκευής που προσδιορίζει με μη επεμβατικό τρόπο το επίπεδο οξυγόνου στο αίμα καθώς επίσης και το ρυμό των καρδιακών παλμών. Η γνώση του επιπέδου του Οξυγόνου στο αίμα είναι ιδιαίτερα σημαντική σε ασθενείς που βρίσκονται υπό ειδική ιατρική περίθαλψη, καθώς και σε ασθενείς υπό εγχείρηση, αφού η καλή οξυγόνωση είναι ο βασικότερος παράγοντας διαβίωσης. Η κατάσταση που προκαλει από μειωμένη οξυγόνωση ονομάζεται υποξία. Η αρχή λειτουργίας της συσκευής βασίζεται στον εμπειρικό νόμο απορρόφησης του Beer- Lambert και στα χαρακτηριστικά απορρόφησης του ερυθρού και του υπέρυθρου μήκους κύματος φωτός από τη οξυγονωμένη και μη αιμοσφαιρίνη. Κάποιο σημείο του σώματος –στη δική μας εφαρμογή ο δείκτης του χεριού- τοποθετείται σε ειδικό probe, όπου δυο φωτοεκπέμπουσες δίοδοι εκπέμπουν ενναλάξ ερυθρό και υπέρυθρο φως. Στη συνέχεια το μέρος της ακτινοβολίας που δεν απορροφάται από το ανθρώπινο μέλος ανιχνεύεται από δύο φωτοανιχνευτικές διόδους τοποθετημένες στην κάτω πλευρά του δαχτύλου. Το οπτικό σήμα μετατρέπεται από τις διόδους σε ηλεκτρικό. Ακολουθεί ένα αναλογικό κύκλωμα ενίσχυσης, που συμπεριλαμβάνει δύο ενισχυτές και ένα ψηφιακό ποτενσιόμετρο για τη ρύθμιση του κέρδους των ενισχυτών. Το αναλογικό σήμα μετατρέπεται σε ψηφιακό με τη χρήση του ADC12 μετατροπέα που αποτελει περιφερειακό στοιχείο του msp430F169 μικροεπεξεργαστή που χρησιμοποιήσαμε. Ο μικροεπεξεργαστής αυτός επιλέχτηκε για τις ιδιαίτερες δυνατότητες χαμηλής κατανάλωσης που διαθέτει, καθώς επίσης και για την ποικιλία περιφερειακών συσκευών του. Στη συνέχεια με τη βοήθεια του Software που υλοποιήθηκε σε C γλώσσα προγραμματισμού, τα δείγματα που λαμβάνονται από τον ADC12 αφού φιλτραριστούν ώστε να απορριφθεί ο περιβαλλοντικός θόρυβος, διέρχονται από ένα δεύτερο φίλτρο αποκοπής της DC συνιστώσας, η οποία προκύπτει απο την απορρόφηση διαφόρων τμηάτων του δαχτύλου, όπως οι φλέβες, το δέρμα, ο ιστός και το οστό. Έτσι απομένει η AC συνιστώσα που αντιστοιχεί στην αρτηριακή απορρόφηση, η οποία και μας ενδιαφέρει. Τα δείγματα του ΑC πλέον σήματος αποθηκεύονται σε πίνακες για την περαιτέρω μαθηματική τους επεξεργασία ώστε να διεξαχθούν τα αποτελέσματα που αντιστοιχούν στο ρυθμό των παλμων και στο επίπεδο κορεσμού του Οξυγόνου. Επίσης, αξίζει να σημειωθεί ότι γίνεται εκτεταμένη χρήση του Timer A που διαθέτει ο msp430f169 για τον χρονισμό του προγράμματος και τον έλεγχο της διαδοχής των διεργασιών. Αυτό γίνεται ώστε η MCU να παραμένει όσο το δυνατόν μεγαλύτερο χρονικό διαστήμα σε LPM3 (κατάσταση αναμονής με κατανάλωση μικρότερη των 2μΑ και χόνο αφύπνισης μικρότερο των 6μs), όταν δε λειτουργεί, ώστε να μειώνεται σημαντικά η κατανάλωση της συσκευής και δεύτερον για να μπορέσουμε να υπολογίσουμε το χρόνο δειγματοληψίας του προγράμματος ανεξαρτητοποιώντας τον από το χρόνο εκτέλεσης του κώδικα. Τέλος, οι απαίτησεις τουπρογράμματος σε μνήμη είναι 3860 bytes για μνήμη κώδικα, 1785 bytes για μνήμη δεδομένων και 556 bytes για μνήμη σταθερών. Ακόμα οι απάτησης ισχύος ειναι εξαιρετικά χαμηλές αφού η συσκευή λειτουργεί με μπαταρία των 6V. / Pulseoximetry is the proceedure through which are defined the level of the oxygen saturation and the heart beat ratio.In this paper we examine the theoratical basis on which the device has been developed,we present the basic characteristics of the msp43of169 microproccessor which has been used and we describe the hardware and the software of the developement.Finally we conclude presenting the results and the graphic of the device.

In-Situ Combustion (ISC) is a very complex thermal recovery process that is strongly affected by the chemical composition and physical properties of reservoir rock and fluids. Stability of the process depends on the amount of heat continuously generated from the chemical reactions between fuel formed during ISC and injected oxygen. Heat generation depends on the amount of fuel formed, which, in turn, is affected by initial oil saturation (IOS). Thus, in this study, ISC process dynamics were investigated at various saturations on 7.5 °API Peace River bitumen, under 3.4 l/min air injection rate. Through one-dimensional combustion tube experiments higher combustion front temperatures were observed for increased IOS. The degree of bitumen upgrading was determined in terms of viscosity and API gravity changes. Correlations for hydrogen-carbon ratio, air requirement, consumed fuel, and combustion front velocity were obtained. Good burning characteristics of Peace River bitumen resulted in stable self-sustained combustion with 26.01% IOS. However, an experiment with 13.39% IOS failed because of insufficient fuel generation. Furthermore, X-Ray cross-sectional images were taken along the combustion tube after each run to support and enhance the interpretation of experimental results. Particularly, fluctuations in concentrations of produced gas composition were explained with computed tomography (CT) data.

No description available.

Les contrôleurs à réinitialisation sont une classe de systèmes hybrides dont la valeur de tout ou partie des états peut être instantannément modifiée sous certaines conditions algébriques. Cette interaction entre dynamique temps-continu et temps-discret de ces contrôleurs permet souvent de dépasser les limites des contrôleurs temps- continu. Dans cette thèse, nous proposons des conditions constructives (sous forme d'Inégalités Matricielles Linéaires) pour analyser la stabilité et les performances de boucle de commande incluant un contrôleur à réinitialisation. En particulier, nous prenons en compte la présence de saturation en amplitude des actionneurs du système. Ces non- linéarités sont souvent source d'une dégradation des performances voir d'instabilité. Les résultats proposés permettent d'estimer le domaine de stabilité et un niveau de performance pour ces systèmes, en s'appuyant sur des fonctions de Lyapunov quadratiques ou quadratiques par morceaux. Au delà de l'aspect analyse, nous exposons deux approches pour améliorer la région de stabilité (nouvelle loi de réinitialisation et stratégie "anti- windup").

Recycled concrete aggregate (RCA) is a construction material, which is being used in the Canadian construction industry more frequently than it was in the past. The environmental benefits associated with RCA use, such as reduced landfilling and natural aggregate (NA) quarrying, have been identified by industry and government agencies. This has resulted in some incentives to use RCA in construction applications. Some properties of RCA are variable and as a result the material is often used as a structural fill, which is a low risk application. The use of RCA in this application is beneficial from an overall sustainability perspective but may not represent the most efficient use of the material. Efficient use of a material means getting the most benefit possible out of that material in a given application. The initial step in efficient material use is evaluating how a material affects its potential applications. In the case of RCA, this includes its use in concrete as a coarse aggregate. RCA is made up of both aggregate and cement mortar from its original application. Its make-up results in absorption capacities, which are higher than NA. Its high absorption capacity indicates that RCA can retain a relatively large proportion of water. Internal curing of concrete is the practice of intentionally entraining reservoirs of water within concrete. This water is drawn into the cement at a beneficial point in the cement hydration process. This water allows for a more complete hydration reaction, less desiccation, a less permeable concrete pore system, and less susceptibility to the negative effects of poor curing. The potential for RCA to act as an internal curing agent was evaluated in this research. Two RCA types were studied in the course of this research, one RCA of high-quality and one low-quality. These were compared to one NA type, which served as experimental control. Neither RCA type was found to desorb significant amounts of entrained water at relative humidity levels between 85% and 93%. This behaviour indicates that they would not behave as a traditional internal curing agent. Within concrete, the initial saturation levels of these RCAs were 0%, 60% and 100% of their full absorption capacity. The mixtures ranged from 30% RCA (by volume of coarse aggregate) to 100% RCA. These mixtures were subjected to two curing regimes, MTO-specified curing conditions and moist curing, in order to gauge the internal curing potential of the RCA. Fully saturated RCA mixtures were found to retain water throughout the course of testing. They were also found to increase the rate of compressive strength gain at early ages in comparison to similarly cured NA mixtures. Full saturation was found to have a negative effect on the thermal expansion behaviour of the concrete at 28 days concrete age. Permeable porosity of concrete was measured as an indicator of more thorough hydration in RCA concrete, but any potential benefits were masked by the increase in permeable porosity associated with permeable RCA. When compared with NA control mixtures and RCA mixtures cured under ideal conditions, it was found that saturated RCA mixtures provided compressive strength benefits. Low-quality RCA, which lost entrained water earlier in the testing period than high-quality RCA, benefitted in terms of early age compressive strength gains under specified curing conditions. High-quality RCA, which retained a relatively higher proportion of its entrained water throughout the early testing period, improved later age compressive strength under spec-curing conditions. Mixtures with 30% RCA (by volume of coarse aggregate) were generally found to not significantly affect the tensile strength, elastic modulus, and permeable porosity of the concrete. Tensile strength and elastic modulus were found to be consistently lower in RCA concretes, while permeable porosity was consistently higher. However, the magnitudes of these changes were not large enough to be statistically significant based on the testing regime employed. Compressive strength was significantly improved at 28 days when the 30% RCA was fully saturated. 30% RCA mixtures significantly reduced the thermal expansion of concrete at 28 days, which could provide particular benefit to concrete pavement applications. Overall, RCA saturation in new concrete had both positive and negative effects on the properties of concrete, which should both be considered in the context of the application for which RCA concrete is being considered. Specifically, concrete applications with the potential for poor curing and the need for reduced thermal expansion could benefit through the inclusion of coarse RCA. For example, these benefits could manifest in reduced thermal cracking at slab joints and reduced thermal stresses due to temperature gradients in pavements.

This thesis develops and evaluates a method to simulate energy consumption and water production for a novel sorption dehumidication pro-cess. The system consists of a chamber comprising a hygroscopic materialand a heating device. The process consists of an adsorption phase anda regeneration phase. For both the regeneration phase and the adsorp-tion phase the model considers the heat distribution by thermal diusionand convection and the water transport by diusion and convection. Forthe regeneration phase the radiation is also considered since the radia-tive power increases with temperature to the power of four. Further, amodel for the condensation process is implemented and a model for thecondensation is suggested. To model the properties of the hygroscopicmaterials, the adsorption curves for SiO2 and AlO2 are investigated. Themodel were evaluated by comparing the simulated values with experimen-tal measurements.The results from the the simulation of the regeneration phase showsa good agreement with experimental data for the power and the energyconsumption even though the simulated values are a bit underestimated,about 10%. The water production is simulated to be about 25% higherthan the measured values. This discrepancy could be explained by aleakage of water vapour that was found in the experimental set up, whichis not considered in the model. This could also explain the underestimatedenergy consumption since the condensation energy in the system is toogreat. To improve the accuracy for the model the water leakage wouldneed to be implemented. The overestimation of water seemed to be thesame for the measurements from the same apparatus.For the adsorption phase a developed model, from an article for ad-sorption in silica, was implemented and tuned for the specic system. Thesimulations are in good agreement with the measurements but could betested further for more certainty.

Thesis (MAppSc)--University of South Australia, 1996