This work of well performance modeling is focused on solving problems of transient and pseudo-steady state fluid flow in a rectilinear closed boundaries reservoir. This model has been applied to predict and to optimize gas production from a horizontal well intercepted by multiple transverse fractures in a bounded reservoir, and it also provides well-testing solutions. The well performance model is designed to provide enhanced efficiency with the same reliability for pressure transient analysis, and well performance prediction, especially in complex well fracture configuration. The principle is to simplify the calculation of the pressure response to an instantaneous withdraw, which happens in other fractures, within a shorter computational time. This pressure response is substituted with the interaction between the two whole fractures. This method is validated through comparison to results of rigorous Distributed Volumetric Sources (DVS) method in simple symmetric fracture configuration, and to results of field production data for complex well/fracture configuration of a tight gas reservoir. The results show a good agreement in both ways. This model indicates the capability to handle the situations, such as: various well drainages, asymmetry of the fracture wings, and curved horizontal well. The advantage of this well performance model is to provide faster processing - reducing the computational time as the number of fractures increase. Also, this approach is able to be applied as an optimization and screening tool to obtain the best fracture configurations for reservoir development of economically marginal fields, in terms of the number and dimensions of fractures per well, also with external economic and operational constraints.

Many efforts have been conducted for improving the operation and management of open channel networks. Implementing simulation models and software is an effective step in achieving better operation of control structures in open channel networks. The purpose of this study was to develop a tool in ArcGIS for assisting the open channel network managers in operating flow control structures. This model presents a time schedule for gate operation based on the demands at turnouts through the water usage schedule of the network. The developed model was designed to be added as a tool to ArcToolbox in ArcGIS. Any ArcGIS user who has access to ArcView or ArcInfo can add this tool to ArcToolbox. Using ArcGIS Geoprocessing tools, ModelBuilder, Scripting and ArcToolbox tools, the proposed model, "Arc-Canal", was created. Arc-Canal is implementable for irrigation networks that open channel network are digitized in ArcGIS. Simulation is for the gravity flow in open channels without any pump in the network. Calculations are based on steady flow. All hydraulic calculations for water level, gates, and weirs are based on the methods defined in "Open-Channel Hydraulics" (Chow 1959). Most of the available flow simulation models are complicated individual software for which user needs to be trained to install and use it. Also most of these software are not free accessible. Arc-Canal is an easy to use tool that anyone with the knowledge of working with ArcGIS can run it. By adding the tool to ArcToolbox and following the described naming method, and entering the required data, model is ready to run. The developed model is a free access tool. Most of the channels in open channel networks in south Texas have mild bottom slope and flow is steady gravity flow. It is desired that the developed model will be a tool to assist irrigation districts in south Texas.

Abstract Spray cooling is frequently encountered in a number of engineering applications. An experimental study was made to investigate the effect of liquid sprays used to cool a hot surface. Both pure water and R-134a were served as a working medium sprayed from a single circular nozzle onto a Pt plated surface of an electrically heated surface. Spray cooling tests were performed for steady state and transient experiment. Cooling characteristics curves were obtained over a range of Weber number(Water¡G80¡B148¡B231¡AR-134a¡G50¡B96¡B152),pressure drop of liquid(0.1Mpa¡B0.15Mpa¡B0.2Mpa),degree of subcooling (Water¡G55¢J¡B60¢J¡AR-134a¡G2¢J¡B4¢J) and initial temperature(Water¡G240¢J¡AR-134a¡G60¢J). Thermal design data of high performance as well as more and further physical insight of the above-stated spray cooling heat transfer can be acquired. The results will hopefully be helpful not only for the academia but for the industry.

The human mitochondrial polymerase (pol γ) is a nuclearly-encoded polymerase that is solely responsible for the faithful replication and repair of the mitochondrial genome. The Y955C mutation in pol γ results in early onset progressive external ophthalmoplegia, premature ovarian failure, and Parkinson’s disease. It is believed that the position of this Y955 residue on the catalytic helix in the polymerase makes it responsible for stabilizing the incoming nucleotide. I have investigated the kinetic effect of the Y955C mutation. Mutation of the tyrosine to a cysteine resulted in a decreased maximum rate of polymerization and increased the dissociation constant for incoming nucleotide. In turn, this decreased catalytic efficiency by 30 to 100-fold. In addition, the polymerase did not incorporate all bases with the same efficiency, it was most efficient when incorporating dGTP opposite a dC, but showed less efficient catalysis when faced with an A:T or T:A base-pair. The polymerase also showed reduced discrimination against misincorporation events. However, when presented with an oxidatively-damaged base, 8-oxo-deoxyguanosine, the polymerase chose to incorporate the base in the correct conformation opposite a dC, discriminating against the mutagenic incorporation of 8-oxo-dGTP opposite a dA. The results presented in this thesis suggest that the severe clinical symptoms of patients with this mutation are at least due in part to the reduced efficiency and discrimination of this polymerase γ mutation. / text

This report estimates the steady-state, non-point source bacteria pollution along the international river system of the Lower Rio Grande / Río Bravo between Falcón Reservoir and the Gulf of Mexico. The results from this report may be used by environmental agencies in the United States and México in order to develop a steady-state water quality model of the bacterial load in this river system. This report creates a GIS-based estimation of the steady-state, non-point source pollution from sources such as failing septic tanks, untreated sewage, grazing animals, and wildlife in the watershed. This report also provides recommendations for environmental agencies when developing the water quality model. The results and methodology developed for this report may be used as part of the Lower Rio Grande / Río Bravo Watershed Initiative, a binational pilot project to develop a plan to restore and protect the quality of the Rio Grande/Río Bravo. / text

Personas con discapacidad motora presentan inconvenientes en el desarrollo de actividades tales como caminar, correr, comer. Además, en su mayoría, la visión y el intelecto no se ven afectados. Estas deficiencias no le permiten al manipular dispositivos tecnológicos que podrían ayudarlo a mejorar su calidad de vida como los smartphones. Presentamos una solución que permite superar esta limitación apoyada en la tecnología Brain Computer Interface). / Revisión por pares

The effect of surface roughness on jet impingement heat transfer was investigated in this research. A numerical analysis was conducted for free surface slot jet impinging normally onto a heated plate. Six different geometries and three different plate materials were investigated. The cooling fluid used for the analysis was water, and the flow was laminar with a range of Reynolds number (Re) from 500 to 1000. Temperature distribution, local and average heat transfer coefficient, and local and average Nusselt number were presented for each case. The steady state heat transfer results show that the increase in Reynolds number (Re) increases the local heat transfer coefficient and the local Nusselt number. Impinging the jet nozzle directly onto a step has a better heat transfer enhancement than impinging the jet nozzle in between steps. Materials with low thermal conductivity exhibit large variation in temperature along the solid-fluid interface. The variations of the interface temperature become smaller between all cases when applying the isothermal boundary condition. The transient heat transfer results show that the temperature of the interface increases with time until steady state condition is met. Materials with high thermal diffusivity reach the steady state condition with less time. The increase in surface roughness increases the time required to reach the steady state condition. The highest rates of heat transfer were found at locations where no fluid recirculation occurs. It takes less time to reach steady state condition when applying the isothermal boundary condition at the bottom surface of the plate.

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No description available.

The performance of a phosphoric acid fuel cell reactor, (PAFC), with n-hexadecane, C16H34, canola biodiesel, soybean biodiesel and petroleum diesel fuel has been investigated. Fifteen-hour steady-state operation was achieved with each of the diesel fuels. This is the first extensive study reported in the literature in which n-hexadecane is used directly as the fuel. It is also the first study of a fuel cell operated with petroleum diesel fuel. Identification of steady-state conditions (temperature = 190oC, molar ratio of fuel to water = 414) is significant because it demonstrates that stable fuel cell operation is technically feasible when operating a PAFC with diesel fuels. Degradation in fuel cell performance was observed prior to reaching steady-state. The degradation was attributed to a carbonaceous material forming on the surface of the anode. After treating the anode with water the fuel cell performance recovered. However, the fuel cell performance degraded again prior to obtaining another steady-state operation. Several consistent observations suggested that the carbonaceous material formed from the diesel fuels might be a reaction intermediate necessary for steady-state operation. Finally, the experiments indicated that water in the phosphoric acid electrolyte could be used as the water required for the anodic reaction. The water formed at the cathode could provide the replacement water for the electrolyte, thereby eliminating the need to provide a water feed system for the fuel cell.