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The implementation of a ported shroud casing treatment is often used to extend the operating range of a centrifugal compressor. This work utilizes the STAR-CCM+ CFD package to analyze steady-state, single-passage simulations of a centrifugal compressor with and without a ported shroud to better understand how a ported shroud affects compressor flow physics. Verification and validation of simulations were conducted by comparison of results with a time-accurate full-annulus simulation and experimental data. Four different ported shroud revisions were considered and modeled along the full range of their stable operation, with emphasis placed on the flow limits of choke and stall. A ported shroud is found to improve the choked mass flow limit by increasing the aerodynamic area of the compressor. Near-stall operation is improved through flow recirculation through the ported shroud. This flow, which is induced with a large component of tangential velocity from having passed the impeller blades' leading edge once, reduces the impeller incidence. The influence of a strut is found to restrict both limits of operation by reducing the aerodynamic area and obstruction of tangential velocity. The revisions considered demonstrate that facilitation of flow entering the ported shroud under either near-stall or choked conditions causes a noteworthy improvement in performance. Such alterations, in this application, demonstrate a 3.3% improvement in choked mass flow rate under choked conditions and an 1.3 degree reduction in impeller incidence under near-stall conditions, as compared to the initial ported shroud design. Understanding the effect that a ported shroud casing treatment has on compressor flow physics, especially near its limits of operation, suggests methods for improving centrifugal compressor design to increase its stable operating range.

Background: Sorting algorithms are an essential part of computer science. With the use of parallelism, these algorithms performance can improve. Objectives: To assess parallel sorting algorithms performance compared with their sequential counterparts and see what contextual factors make a difference in performance. Methods: An experiment was made with quicksort, merge sort, load-balanced parallel merge sort and hyperquicksort. These algorithms executed on Ubuntu 20.10 and Windows 10 Home with three data sets, small (106 integers), medium (5  106 integers) and large (107 integers). Each algorithm executed 1 000 times per data set within each operating system resulting in 6 000 executions per sorting algorithm.  Results: With the data from the executions, it was concluded that hyperquicksort had the fastest execution time. On average load-balanced parallel merge sort had the slowest execution time. The fastest operating system was Ubuntu 20.10, all but one algorithm executed faster on Ubuntu. Conclusions: The results showed that the fastest algorithm was hyperquicksort, but other conclusions also arose. The data set size correlated with both the execution time and speedup for a given parallel sorting algorithm. When the data set size increased, both the execution time and the speedup increased.

This project represents the ever-changing methods surrounding Enhanced Recovery after Surgery and the protocols that compose it. The purpose of this study is to expand education of ERAS guidelines and improve patient outcomes through furthering staff education. Enhanced Recovery After Surgery has been a part of perioperative departments worldwide after being introduced in the 1990s by Northern European general surgeons and has been adapted and modified since its introduction (ERAS Society History, 2022). The preoperative and postoperative process is ever-changing and is difficult for staff to keep up with. Many staff members find it difficult to stay on top of the most recent protocols. From clerical staff to nurses to surgeons there is a breakdown in the process of ensuring patients receive the optimal benefits if ERAS. This presentation will serve to both educate viewers on the latest ERAS recommendations as well as help develop and define a workflow for ensuring staff members have the most updated guidelines available to streamline the process and provide the best recovery experience for patients.

Bibliography: pages 104-110. / Two technologies, distributed operating systems and UNIX are very relevant in computing today. Many distributed systems have been produced and many are under development. To a large extent, distributed systems are considered to be the only way to solve the computing needs of the future. UNIX, on the other hand, is becoming widely recognized as the industry standard for operating systems. The transputer, unlike. UNIX and distributed systems is a relatively new innovation. The transputer is a concurrent processing machine based on mathematical principles. Increasingly, the transputer is being used to solve a wide range of problems of a parallel nature. This thesis combines these three aspects in creating a distributed implementation of UNIX on a network of transputers. The design is based on the satellite model. In this model a central controlling processor is surrounded by worker processors, called satellites, in a master/ slave relationship.

Bibliography: pages 90-94. / The DISTRIX operating system is a multiprocessor distributed operating system based on UNIX. It consists of a number of satellite processors connected to central servers. The system is derived from the MINIX operating system, compatible with UNIX Version 7. A remote procedure call interface is used in conjunction with a system wide, end-to-end communication protocol that connects satellite processors to the central servers. A cached file server provides access to all files and devices at the UNIX system call level. The design of the file server is discussed in depth and the performance evaluated. Additional information is given about the software and hardware used during the development of the project. The MINIX operating system has proved to be a good choice as the software base, but certain features have proved to be poorer. The Inmos transputer emerges as a processor with many useful features that eased the implementation.

Indiana University-Purdue University Indianapolis (IUPUI) / Understanding the operating profile of different heavy-duty vehicles is needed by parts manufacturers for improved configuration and better future design of the parts. This study investigates the use of a tournament classification approach for both vocation and fleet identi- fication. The proposed approach is implemented using four different classification techniques, namely, K-Means, Expectation Maximization, Particle Swarm Optimization, and Support Vector Machines. Vocations classifiers are developed and tested for six different vocations ranging from coach buses to rail inspection vehicles. Operational field data are obtained from a number of vehicles for each vocation and aggregated over a pre-set distance that varies according to the data collection rate. In addition, fleet classifiers are implemented for five fleets from the coach bus vocation using a similar approach. The results indicate that both vocation and fleet identification are possible with a high level of accuracy. The macro average precision and recall of the SVM vocation classifier are approximately 85%. This result was achieved despite the fact that each vocation consisted of multiple fleets. The macro average precision and recall of the coach bus fleet classifier are approximately 77% even though some fleets had similar operating profiles. These results suggest that the proposed classifier can help support vocation and fleet identification in practice.

Mobile devices are increasingly becoming a greater crutch for all generations. All the while, these users are garnering a greater desire for privacy and style. Apple presents a device that is known for its security, but lacks major user customization. On the other hand, Google has developed a device that is keen to customization with Android, but can be susceptible to security flaws. This thesis strives to discuss the security models, app store protections, and best practices of both mobile operating systems. In addition, multiple experiments were conducted to demonstrate how an Android device could be more easily compromised after altering few settings, as well as to demonstrate the privileges, both good and bad, that could be gained by jailbreaking an iOS device.

The adverse effects of climate change, the steady depletion of fossil fuels, and the industrialization of developing countries have resulted in an increased supply and demand of renewable thermal energy. Renewable thermal energy sources like solar thermal energy produce fewer local emissions but have a temporally inconsistent power output. The consumer space heating and domestic hot water demands also vary as a function of time. This creates a mismatch between thermal energy supply and demand. Energy storage is one method of solving this problem. However, conventional methods, like hot water storage, are voluminous and can only store heat for short periods of time. Therefore, compact long-term energy storage technologies, like sorption-based energy storage systems, require research and development. The current work aims to identify and develop suitable materials for sorption-based energy storage systems and to determine the effects of operating conditions on the performance of thermal energy storage systems. A material screening study was performed, which identified MCM-41, SAPO-34, and silica gel, which are all silica-based materials, as suitable materials for sorption-based energy storage. The effects of key operating variables for a silica gel/water-vapour adsorption-based energy storage system were quantified and optimized. The optimized system energy storage density value was nearly double that of unoptimized systems. The effects of salt impregnation were investigated by impregnating different hosts with MgSO4 salt and varying the concentration of the salt in the host material. All composites were stable after three hydration/dehydration cycle. A silica gel/MgSO4 hybrid containing 33 wt% MgSO4 was found to have the highest energy storage density of all of the MgSO4-based composites. Finally, CaCl2, a promising hygroscopic for thermal energy storage was stabilized via impregnation into silica gel and encapsulation in methylcellulose. A novel synthesis technique involving the simultaneous impregnation of silica gel with CaCl2 and encapsulation in methylcellulose produced a stable encapsulated salt-in matrix composite with a high energy storage performance.

The thesis investigates pipeline plugging mechanisms that have occurred during interim stabilization transfers at Hanford. A laboratory-scale saltwell pumping test loop was designed to evaluate a surrogate of Hanford Tank 241-SX-104 supernate. The effect of surrogate flow rate, cooling water flow rate and phosphate concentrations on plugging mechanisms was investigated. Critical parameters like particle and agglomerate size, velocity and bed growth rate were determined. Theoretical models were used to compare the experimental pressure rise and temperature drop of the surrogate in the channel. An operating region in which a plug would not form was developed, based on the experimental results. Experiments are also reported on plug remediation. Unplugging experiments at varying pump pressure heads and residence time of plug in the line were performed.