With the possession of extremely broad unique properties, particulate reinforced aluminum composites are very attractive in diverse applications. Aluminum matrix particulate composites are challenging to work with. A single pressing and sintering process was used to fabricate the reinforced aluminum composites in this study. The key advantage of this method is its comparative low expense. However, abrasive reinforcement powders can lead to shorter tool life. To study the fundamental wear mechanisms during the die compaction process, a new method was developed and combined with experiments to quantify tool wear. Automatic die compaction experiments and tribological experiments are employed in this study. The tribologcial experiments consist of a modified pin-onlat test and a modified loop test. Mass loss of tools was recorded during all the experiments. A new tool wear model was used in this study to investigate effect of different hard phase and different lubricant level on die compaction process.

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No description available.

No description available.

One in three women and one in five men will experience a fracture due to osteoporosis in their lifetime. The clinical significance of osteoporosis is largely due to increased fracture rates, particularly in the hip and spine, that may lead to immobility and subsequent hospitalization. This may increase the risk of cardiac complications, pneumonia and pulmonary embolism, significantly impacting in-hospital mortality. It is a major health issue, with an osteoporotic fracture occurring every 3 seconds worldwide. Exercise is often recommended for people with osteoporosis and has been shown to maintain bone mass and reduce falls with fewer side effects. Although exercise has multiple benefits, adherence to this activity is poor, with 50% of those registered in a program dropping out within the first 6 months. One method to increase adherence to exercise is to identify the facilitators, barriers and preferences to physical activity. Identification of these facilitators and barriers may allow researchers and clinicians to design better exercise programs that increase motivation. This dissertation discusses the development of a new tool that can measure the factors that affect exercise adherence and calculates the content and construct validity and the test-retest reliability of the measure in the osteoporosis population. This tool has potential applications in both the research setting and in clinical practice. Investigators can use this tool to survey their population of interest and use this information to leverage the facilitators and limit the barriers in their methodologies when designing activity programs, while clinicians can identify and design better exercise prescriptions for individual clients. / Thesis / Master of Health Sciences (MSc)

Crash response planning is a vital component of emergency management and highway emergency response planning. Evaluation of coverage of medical facilities is required to determine adequate access from crash sites to medical facilities. This study proposes a proof of concept for a planning tool that evaluates fatal and serious injury crash response coverage from crash sites to medical facilities in the Commonwealth of Virginia. Calculated travel times from fatal crash sites to medical facilities are compared with reported travel times to better estimate travel time modification factors. The modified travel times are used to determine coverage areas and evaluate serious injury crash response coverage of medical facilities in Virginia. A geo grid approach is used to demonstrate the proof of concept for a crash response planning tool. A risk grid is developed based on the aggregate number of fatal and serious injury crashes. This study includes serious injury crash response coverage because the number of serious injuries and serious injury rate are now included as reportable safety performance measures for state highway safety agencies. A mitigation grid is developed based on the travel time to the closest facility. Finally, a planning grid that combines risk and mitigation factors based on a decision matrix is presented. The resulting tool serves as a proof of concept for developing a crash response planning tool which enables planners to identify areas that do not have timely access from crash sites to medical facilities. / Master of Science / An objective of emergency responders is to safely transport crash victims from crash sites to medical facilities. Ensuring adequate access is an important goal of highway safety professionals. This study proposes a proof of concept for a planning tool that evaluates this access in the Commonwealth of Virginia. This study focuses on serious injury crash sites because the number of serious injuries and serious injury rate are now included as reportable safety performance measures for state highway safety agencies. Travel times from serious injury crash sites to medical facilities are used to identify areas that do not have timely access. Risk and mitigation assessments are performed by dividing the study area into equal sized cells. Risk and mitigation assessments are based on number of crashes and response travel times to the closest medical facility, respectively. These assessments are used to generate a proof of concept for a crash response planning tool which enables planners to identify areas that do not have timely access from crash sites to medical facilities.

Health-system guidance (HSG) is expected to assist with making decisions about addressing problems or achieving goals in health systems. However, the implementation of HSG is challenging due to the complexity of health-system policymaking. Existing guideline implementation tools focus on clinical practice guidelines and might not be suitable for HSG. This dissertation aims to bridge this gap by developing a theoretical framework and a tool designed to support HSG implementation at both national and subnational levels. It achieves these objectives through three original scientific contributions. The first study uses a critical interpretive synthesis of the existing literature to develop a theoretical framework. This framework identifies facilitators of, barriers to, and strategies for supporting HSG implementation across six different levels: the political system, health system, community, organization, providers, and the public/patients. The second study employs a modified Delphi method to identify the components of an HSG implementation tool based on this framework. The third study adopts a formative evaluation study design to explore – through interviews with guideline implementers – whether, how, and why the HSG implementers will use the tool and how it can be refined, leading to the further development of the tool. These studies collectively offer theoretical, methodological and substantive insights into understanding the facilitators, barriers, and strategies crucial for the effective implementation of HSG. The developed HSG implementation framework and accompanying tool can be useful for supporting the implementation of HSG covering varied topics and in different contexts, including low-, middle- and high-income countries. / Thesis / Doctor of Philosophy (PhD) / Health-system guidance (HSG) is advice created to help governments make better decisions on how to improve health systems. The implementation of HSG is complicated due to the complex ways in which government policy about health systems is made. Most existing implementation tools are designed for implementing clinical practice guidelines, not HSG. This dissertation addresses this gap by focusing on HSG implementation, bringing together insights from a series of three studies. The first study develops a framework about the facilitators of, barriers to, and strategies for HSG implementation at different levels (e.g., patients, organizations and communities). The second study gathers expert opinions about how the framework can be used to develop the components of a tool. The third study examines whether, how, and why this tool will be used with people who implement HSG, which supports the further refinement of the tool.

The importance of a well-formulated set of software requirements contributing to a successful software development effort has been underscored in recent times. However, the software industry still faces a dearth of process models and artifacts populating the requirements generation process. Of those that do exist, they are often disconnected and narrowly focused, providing little structure to the requirement generation phase. Current methodologies advocate useful guidelines, but do not enforce them. To address these concerns, we introduce the "Synergistic Approach to Software Requirements Generation" — an approach composed of two components — a model and an interactive tool implementing the model. The first component is the Synergistic Requirements Generation Model (SRGM). The SRGM is complete with detailed processes spanning the entire software requirements generation phase. These processes have been identified and decomposed to low-level activities with the intent to improve clarity and understanding. The second component entails the An Interactive Tool for modeling the SRGM (itSRGM) codifying the structure dictated by the model. The tool enforces guidelines and provides visual representations of the progression of activities involved in the requirements generation process. / Master of Science

This thesis describes the design and implementation of an innovative drawing interpretation tool for the sight-impaired. The move towards Graphical User Interfaces in today's computer era presents many challenges to those with impaired vision. Although there are many tools to aid this group in reading and writing text-based electronic documents, few software packages are available to help the sight-impaired interpret electronic images. This new tool, known as ImagePilot 2.0, processes electronic image files that contain line drawings and produces audio feedback to guide the user through the drawing. ImagePilot 2.0 receives input through a pointing device, thereby providing the user with a means of examining a drawing interactively, and serving as an aid for recognizing the outlines of familiar shapes and objects. In this study, a "line drawing" is a simple image that contains line segments and curves, without any shading or colors. It can be represented as a 2-dimensional array of picture elements (pixels), in which each pixel is either black or white. The drawing is represented by a pattern of black (foreground) pixels against a white background. Typically, groups of connected foreground pixels represent segments or curves that are associated with a single object. ImagePilot 2.0 makes it possible for a sight-impaired user to interrogate such an image. Line drawings can be stored in many different electronic formats. ImagePilot 2.0 supports valid Graphic Interchange Format (GIF) files. If the foreground image regions in the file are wider than one pixel in width, a Zhang-Suen thinning algorithm is applied to thin the drawing. The tool identifies the separate regions in the drawing and decides on the best starting point for each region. Once a starting point is chosen, the drawing is processed using a modified chain-coding algorithm. The audio feedback consists of two types of audio cues, verbal and tone, along with stereo playback. Verbal feedback guides the user with a set of verbal cues played through the speakers. The tone feedback uses three tones representing above, level, and below the horizontal. The left and right speakers provide left and right directional information at each level. Speed is a critical factor in image analysis and interpretation applications. While the tool is receiving and processing input, it must also respond to the user within an acceptable amount of time. ImagePilot 2.0 uses multi-threading and multi-tasking techniques to achieve higher performance speeds. After design and implementation, two groups of people tested the tool. The tool demonstrated the ability to help the user find and trace the segments in the test drawings with high efficiency and acceptable response time. This tool is written in pure Java, and complies with Sun's Java API specification 1.1.7 released in October 1998. The tool functions on systems with multimedia capabilities that have a Java Virtual Machine (JVM) and Java Media Framework (JMF) installed. / Master of Science

With the recent developments of several bridge managements systems and their wide-spread use, bridge engineers are realizing the importance of systematic and well planned investments and appropriate management. However the results are far from satisfactory. Bridge management systems need more effective policy analysis tools that can take advantage of the vast amounts of available information to be more efficient. The objective of this research is to develop a policy analysis tool, which is generic in nature and can be applied to any bridge management system provided all the appropriate data is available. In particular, this policy analysis tool is geared to suit policy making, planning and budgeting for the interstate bridges in the state of Virginia. The policy analysis tool developed in this research is a discrete event simulation model capable of extracting information from text files in the Pontis Data Interchange format and simulate user defined element level policies. The model testing was performed using the interstate bridges of the Salem district in Virginia. All the relevant information was extracted from their PONTIS databases. Several scenarios with varying network policies were simulated. The results indicate the validity and the accuracy of the model. The policy analysis tool is a useful addition to the existing policy analysis tools and is capable of handling probabilistic distributions of data instead of single value averages. This will enable the tool to capture more information thereby making the simulation model more realistic. The general framework that was developed here can be applied to any infrastructure problem, and eventually it should be possible to achieve a discrete event simulation based integrated infrastructure management system. / Master of Science