How we smell is important to a lot of people, as indicated by the high spending on perfumes. Most perfumes are categorized as feminine or masculine, and this gender categorization is an important factor when people purchase perfumes. This thesis explores odor perception and perfume preference when the person sniffing the perfume does not know the commercial gender categorization. Three psychophysical experiments were conducted, in which the participants scaled the femininity and masculinity of the perfumes, indicated preferences, and gender categorized the perfumes. The perfumes were presented both in glass bottles and when applied on human skin. Results of three experiments indicate that female and male participants (20–30 years old) preferred the same perfumes, both for themselves and for their potential partners. The preferred perfumes tended to be “unisex,” that is, perceived as neither strongly feminine nor strongly masculine. The participants did not succeed well in identifying the commercial gender categorizations of the perfumes, and they did not succeed in guessing the gender of the human when the perfumes were applied on human skin. The commercial gender associations of the perfumes only corresponded to how they were perceived in the case of extremely feminine or extremely masculine perfumes. I conclude that the gender categorizations of most perfumes are not related to how they are actually perceived. / <p>At the time of the doctoral defence the following paper was unpublished and had a status as follows: Paper 2: Manuscript.</p>

Con esta tesis doctoral aproximamos la teoría de la inferencia gramatical y los estudios de adquisición del lenguaje, en pos de un objetivo final: ahondar en la comprensión del modo como los niños adquieren su primera lengua mediante la explotación de la teoría inferencial de gramáticas formales.Nuestras tres principales aportaciones son:1. Introducción de una nueva clase de lenguajes llamada Simple p-dimensional external contextual (SEC). A pesar de que las investigaciones en inferencia gramatical se han centrado en lenguajes regulares o independientes del contexto, en nuestra tesis proponemos centrar esos estudios en clases de lenguajes más relevantes desde un punto de vista lingüístico (familias de lenguajes que ocupan una posición ortogonal en la jerarquía de Chomsky y que son suavemente dependientes del contexto, por ejemplo, SEC).2. Presentación de un nuevo paradigma de aprendizaje basado en preguntas de corrección. Uno de los principales resultados positivos dentro de la teoría del aprendizaje formal es el hecho de que los autómatas finitos deterministas (DFA) se pueden aprender de manera eficiente utilizando preguntas de pertinencia y preguntas de equivalencia. Teniendo en cuenta que en el aprendizaje de primeras lenguas la corrección de errores puede jugar un papel relevante, en nuestra tesis doctoral hemos introducido un nuevo modelo de aprendizaje que reemplaza las preguntas de pertinencia por preguntas de corrección.3. Presentación de resultados basados en las dos previas aportaciones. En primer lugar, demostramos que los SEC se pueden aprender a partir de datos positivos. En segundo lugar, demostramos que los DFA se pueden aprender a partir de correcciones y que el número de preguntas se reduce considerablemente.Los resultados obtenidos con esta tesis doctoral suponen una aportación importante para los estudios en inferencia gramatical (hasta el momento las investigaciones en este ámbito se habían centrado principalmente en los aspectos matemáticos de los modelos). Además, estos resultados se podrían extender a diversos campos de aplicación que gozan de plena actualidad, tales como el aprendizaje automático, la robótica, el procesamiento del lenguaje natural y la bioinformática. / With this dissertation, we bring together the Theory of the Grammatical Inference and Studies of language acquisition, in pursuit of our final goal: to go deeper in the understanding of the process of language acquisition by using the theory of inference of formal grammars. Our main three contributions are:1. Introduction of a new class of languages called Simple p-dimensional external contextual (SEC). Despite the fact that the field of Grammatical Inference has focused its research on learning regular or context-free languages, we propose in our dissertation to focus these studies in classes of languages more relevant from a linguistic point of view (families of languages that occupy an orthogonal position in the Chomsky Hierarchy and are Mildly Context-Sensitive, for example SEC).2. Presentation of a new learning paradigm based on correction queries. One of the main results in the theory of formal learning is that deterministic finite automata (DFA) are efficiently learnable from membership query and equivalence query. Taken into account that in first language acquisition the correction of errors can play an important role, we have introduced in our dissertation a novel learning model by replacing membership queries with correction queries.3. Presentation of results based on the two previous contributions. First, we prove that SEC is learnable from only positive data. Second, we prove that it is possible to learn DFA from corrections and that the number of queries is reduced considerably.The results obtained with this dissertation suppose an important contribution to studies of Grammatical Inference (the current research in Grammatical Inference has focused mainly on the mathematical aspects of the models). Moreover, these results could be extended to studies related directly to machine translation, robotics, natural language processing, and bioinformatics.

Unexpectedly, it was found that when a waterborne polyacrylate adhesive was placed on carbon steel it was not tacky; this was not the case for the same adhesive placed on stainless steel. It was determined that the surface energy, as measured with liquid contact angles, of the adhesive films is significantly different between the two films, with the non-tacky film having a higher surface energy. Atomic force microscopy (AFM) showed that the non-tacky surface has a higher roughness which minimizes the contacting area between the film and a contacting surface. Analysis of the heating of the carbon steel coupon with infrared thermography shows a non-uniform temperature profile at the surface. This experimental data is corroborated using a 2-D heat transfer model that incorporates the heat transfer characteristics of the various components of carbon steel. Surface driven flow, or Marangoni convection, can develop from temperature gradients and are known to cause increased roughness in polymer films. IR thermography measurements of the adhesive film during drying shows larger temperature differences for the films on carbon steel than on stainless steel. These larger temperature differences induce greater Marangoni convection, which result in the rougher surfaces on carbon steel that were measured with AFM. The effect of lowering the tack of a polyacrylate film has significant impact in the dryer section of a paper machine. This effect was quantified using the Web Adhesion Drying Simulator, which is a laboratory-scale apparatus that measures the energy required to pull the sheet from a metal surface. By substituting the adhesive-on-stainless steel with the less-sticky adhesive-on-carbon steel surface, the energy required to pull the sheet from the metal surface was reduced significantly and the picking associated with the test was nearly eliminated.

This dissertation describes the fabrication and operation of porous silicon gas sensors. The first chapter describes the motivation behind gas sensor research and provides the reader with background knowledge of gas sensors including the terminology and a review of various gas sensors. The following two chapters describe both how the porous silicon gas sensors are created and how they have been tested in the laboratory. Chapter 4 describes the steps required to create arrays of gas sensors to provide for a selective device through the application of patented selective coatings. Chapter 5 proposes a physical model that leads to a numerical solution for predicting the operation of the gas sensor. The next chapter builds from this model to analyze and optimize the experimental methods that are used to test both this and other gas sensors. The final chapter of this dissertation describes the prototype gas sensor system that has most recently been created, the company that was formed to further the development of that system, and the future applications of the porous silicon gas sensor.

The hot gas temperature in gas turbine engines is far above the permissible metal temperatures. Advanced cooling technologies must be applied to cool the blades, so they can withstand the extreme conditions. Film cooling is widely used in modern high temperature and high pressure blades as an active cooling scheme. In this study, the film cooling effectiveness in different regions of gas turbine blades was investigated with various film hole/slot configurations and mainstream flow conditions. The study consisted of four parts: 1) effect of upstream wake on blade surface film cooling, 2) effect of upstream vortex on platform purge flow cooling, 3) influence of hole shape and angle on leading edge film cooling and 4) slot film cooling on trailing edge. Pressure sensitive paint (PSP) technique was used to get the conduction-free film cooling effectiveness distribution. For the blade surface film cooling, the effectiveness from axial shaped holes and compound angle shaped holes were examined. Results showed that the compound angle shaped holes offer better film effectiveness than the axial shaped holes. The upstream stationary wakes have detrimental effect on film effectiveness in certain wake rod phase positions. For platform purge flow cooling, the stator-rotor gap was simulated by a typical labyrinth-like seal. Delta wings were used to generate vortex and modeled the passage vortex generated by the upstream vanes. Results showed that the upstream vortex reduces the film cooling effectiveness on the platform. For the leading edge film cooling, two film cooling designs, each with four film cooling hole configurations, were investigated. Results showed that the shaped holes provide higher film cooling effectiveness than the cylindrical holes at higher average blowing ratios. In the same range of average blowing ratio, the radial angle holes produce better effectiveness than the compound angle holes. The seven-row design results in much higher effectiveness than the three-row design. For the trailing edge slot cooling, the effect of slot lip thickness on film effectiveness under the two mainstream conditions was investigated. Results showed thinner lips offer higher effectiveness. The film effectiveness on the slots reduces when the incoming mainstream boundary layer thickness decreases.

The objectives of this study are to know the behavioural response of the hagfish, Paramyxine cheni to light and to find out if various parts of hagfish¡¦s body differ in sensitivity to light. Photosensitivity was measured in terms of time lapsed between light on and initiation of behavioural sequence (i.e., the reactive time). Behavioral response was measured by the persistent time from the beginning and ending of the behavioural sequence. Five types of light were used as the stimuli to the whole animal: green light, blue light, yellow light, red light, and white light. The lineup of sensitivity for various wavelengths in increasing reactive times( ranging from 13 seconds to 180 seconds) is: green light, blue light, white light, yellow light, red light. Red light significantly differed from the other four types of light in the reactive time; the hagfish was significantly less sensitive to this red light. Four regions of the body were tested with white light: head, gill aperture, tail and mid-portion between the first gill aperture to cloaca. In addition, two parts of the body were simultaneous tested with stimulate: head and tail (HT). The lineup of sensitivity of various regions of body for increasing reactive times (ranging from 9 seconds to 1200 seconds) is: tail, head, mid-portion between the first gill aperture to cloaca, and gill aperture. Tail was significantly more sensitive than the other three parts of the body. However, sensitivity for HT was significantly higher than the tail. Hagfish¡¦s spontaneous movement (i.e., under dark condition)included a number of behavioural sequences differed in the arrangement of behavior patterns (i.e., rolling, swimming, wiggling, springing, and pause). ¡¥Rolling¡¦ was the most preferred initial pattern in a spontaneous movement sequence. In contrast, illumination on tail evoked a complex motor response. Thus, such response was considered not a simple reflex, but a select of choice. ¡¥Swimming¡¦, on the other hand, is the most preferred initial pattern in the sequence triggered by photo stimulation on the tail. According to fluoresence histochemistry study the rhodopsin-like protein is present in the large oval-shaped cells distributed in the epidermis of hagfish. the number and the size of photo-sensitive cells on the tail and gill aperture and the fluorescence intensity on the tail were significantly higher than that on the gill aperture region.

Inversion Recovery (IR) is a powerful tool for contrast manipulation in Mag- netic Resonance Imaging (MRI). IR can provide strong contrast between tissues with different values of T1 relaxation times. The tissue magnetization stored at an IR image pixel can take positive as well as negative values. The corresponding polarity information is contained in the phase of the complex image. Due to numerous factors associated with the Magnetic Resonance (MR) scanner and the associated acquisition system, the acquired complex image is modulated by a spatially varying background phase which makes the retrieval of polarity information non-trivial. Many commercial MR scanners perform magnitude-only reconstruction which, due to loss of polarity information, reduces the dynamic contrast range. Phase sensitive IR (PSIR) can provide enhanced image contrast by estimating and removing the background phase and retrieving the correct polarity information. In this thesis, the background phase of complex MR image is modeled using a statistical model based on Markov Ran- dom Fields (MRF). Two model optimization methods have been developed. The first method is a computationally effcient algorithm for finding semi-optimal solutions satisfying the proposed model. Using an adaptive model neighborhood, it can recon- struct low SNR images with slow phase variations. The second method presents a region growing approach which can handle images with rapid phase variations. Ex- perimental results using computer simulations and in vivo experiments show that the proposed method is robust and can perform successful reconstruction even in adverse cases of low signal to noise ratios (SNRs) and high phase variations.

Fluorescence lifetime determination and allied studies find application in spectroscopy in general and fiber optic biosensors in particular. Instruments and sensors cited in literature however use open loop, intensity based techniques with sophisticated detectors and components. We propose phase sensitive signal processing schemes to estimate the fluorescence lifetime using simple detectors and components, without compromising on accuracy. The performance of the schemes proposed is analysed and contrasted from a communications (signals and systems) point of view. The resolution and sensitivity limits imposed in processing the signal, by systematic errors and additive noise, are derived for the schemes suggested. It is found that systematic errors impose a phase resolution limit of about 2°. We then study the suitability of different detectors and channels for application in phase sensitive fluorescence biosensors we analyse the effect of systematic limitations as well as additive noise, in the detection/transmission process, from the point of view of the components used. Certain fundamental limits of operation in terms of excitation intensities are derived for different detector-channel combinations, with a view to obtain a given resolution. A photodiode used with a fiber bundle is found to be sufficient for accurate phase read outs with 10"4 radians resolution. A PMT used in conjunction with a multimode fiber serves as a very good device for microsensing applications Lastly, the biosensor for oxygen sensing, the ruthenium complex, is studied for standardisation of the sensor. We examine the quenching of fluorescence, the repeatability and reusability of the sensor, the stability of the instrument and such.

Fractures make both opportunities and problems for exploration and production from hydrocarbon reservoirs. It is always difficult to predict how to optimally produce a fractured reservoir due to the complexity and heterogeneity of fluid flow paths. The following behavior is seen in fractured reservoirs: early water breakthroughs, reduced tertiary recovery efficiency due to channeling of injected gas or fluids, dynamic calculations of recoverable hydrocarbons that are much less than static mass balance and dramatic production changes due to changes in reservoir pressure as fractures close down as conduits. These problems often lead to reduced ultimate recoveries or higher production costs. Polymer gels, in particular in-situ gels that can be placed deep into the reservoir, have been widely used for improved conformance control. In this dissertation, we aim to block the high-permeability zones, fractures in particular, with the microgels to increase the sweep efficiency by diverting the waterflood water to the low permeability zones that still contain unswept oil. vii Polyacrylic acid microgels can swell a thousand fold as the pH of the surrounding solution changes, with an accompanying large increase in viscosity. This pH trigger is simpler than chemical cross-linking and thus offers operational advantages. The ability of pH-sensitive polymers to block high permeability fractures is studied by performing several coreflood and batch experiments. The effect of different rock and salt minerals, polymer concentration, polymer salinity, and temperature on polymer performance is studied in this dissertation. Polymer microgels show excellent consistency in the presence of various salt minerals and in contact with different rock minerals. The placement of microgels into the fractures lowered the overall core permeability in all cases. In addition, polymer microgels were stable after being in reservoir for a month with conditions at 58°C. Consequently, using pH-triggered polymers for conformance control and reducing the permeability of high permeability areas in fractured reservoirs merit further investigations. These polymers are inexpensive and are easy to prepare. The polymer concentration, salinity and shut-in time could be set according to the desired PRF value, injectivity, propagation distance and reservoir mineralogy. / text

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