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The design of an I/O Controller capable of processing data in real time in a tactical training simulator is presented. The controller consists of two microprocessor systems that communicate with peripherals by means of programmed I/O, and with the host computer by Direct Memory Access (DMA) and a serial RS232 link. This thesis addresses both the hardware and software aspects of the controller design.

In this master’s thesis project, future scenarios for year 2050 were constructed for Denmark, Finland and Sweden using an environmentally extended input-output analysis (EEIOA). Scenarios were constructed based on national sustainability targets. A case-specific five stage modeling approach was developed. Approach consists of changes in input-output tables for Electricity grid, Fossil primary energy, Industry sectors, Transport and Allocation of fossil fuel replacements. To represent business-as-usual development, EEIO tables for 2009 were used as reference and baseline scenarios. Constructed scenario models resulted in substantial CO2 emission reductions compared to baseline scenario. In scenario results for Denmark, emissions reduced 98.17 %, in Finland 81.41 % and in Sweden 77.90 %. Furthermore, based on Planetary Boundary framework, greenhouse gas emission carrying capacities were estimated in sectoral level for 2050. Carrying capacities for year 2050 for Denmark, Finland and Sweden were 9909.99 kton CO2-eq, 9049.42 kton CO2-eq and 18691.96 kton CO2-eq, respectively. Compared to radically reduced emissions in scenario results, Denmark and Sweden reached emission levels below estimated national carrying capacities. For Finland, carrying capacity level was exceeded by 2437.77 ktons. EEIOA was found to be an efficient tool for constructing and analyzing explorative long-term scenarios. In addition, it is possible to integrate absolute sustainability thresholds to EEIOA. Scenario results indicate that implementation of the existing national sustainability targets would lead to radical emission reductions in Denmark, Finland and Sweden by 2050 compared to business-as-usual development. Based on the scenario results, transport and industry sectors were identified as the emission hotspot sectors in 2050. EEIOA is a noteworthy method for decision-support for assessing sustainability strategies. With EEIOA, it is possible to allocate and study national sustainability targets on a sectoral level, and that way potentially substantially increase the effectiveness and implementation of defined sustainability targets. However, further research on modeling dynamics, data quality and underlined uncertainties are needed before studied approaches can develop into decision-support tools.

The major objectives of this study are to: (i) improve the understanding of what is meant by economic diversification and economic diversity, (ii) provide a comprehensive conceptual framework for region-specific analysis of the relationship between changing economic structure and economic performance measured in terms of the growth, stability, and distribution of income and employment, and (iii) construct an operational model of a regional economy that can be used to assess the impacts of alternative development strategies. This study attempts to sort out the overlaps, contradictions, and gaps among the different economic and finance theories, and the different definitions and measures of economic diversification and diversity. The subject of economic diversification or diversity is addressed in the context of the question: "What is the relationship between a region’s changing economic structure and performance?" A structural model of a regional economy, an extended input-output model based on a social accounting matrix (SAM), serves as the foundation of the conceptual framework and operational model. The SAM-based input- output model explicitly depicts the functional relationship between economic structure and performance. The region’s demand, production technologies, and trade flows are included as part of economic structure. Economic performance is measured as the growth, stability, and distribution of regional income and employment, by occupation group. The structural model is used to analyze the relationship between economic structure and performance for a given time period, and to analyze changes over time. Growth, stability, and distributional impacts are considered simultaneously. By doing this, potential tradeoffs can be explicitly addressed. To identify the structural sources of growth and stability, the SAM-based input-output model is decomposed at different points in time. By decomposing a SAM-based model it is possible to analyze structural sources of growth and stability in terms of both supply and demand factors. Alternative development strategies can be modelled using this conceptual framework. The operational model quantifies the relationship between: (i) the anticipated growth and stability of exogenous final demands, and (ii) the anticipated growth, stability, and distribution of endogenous income and employment, by occupation group. The operational model focuses attention on the distributional impacts of changing economic structure and performance. The relationship between a region’s social welfare, and the aggregation scheme and accounting stance used in the analysis of economic impacts are explicitly addressed. As such, there are explicit social welfare criteria for comparing and ranking alternative development strategies. The operational model presented in this study is well-suited to many popular input-output application packages. / Ph. D.

This study was designed to investigate whether learning style and attitudes toward voice input technology were related to performance in using the technology. Three null hypotheses were tested: (a) No differences exist in the performance in dictating a paragraph using voice input for individuals with different learning styles; (b) No differences exist in attitude toward voice input for individuals with different learning styles; and (c) No interaction exists for the performance scores for individuals with different learning styles and different attitudes toward voice input technology. The statistical procedure used to examine the hypotheses was analysis of variance. Participants were 50 students preparing to become vocational teachers enrolled in vocational education courses at Virginia Tech. Procedures involved having the participants complete three stages. First, they completed the Gregorc Style Delineator (GSD) learning style instrument. Due to a lack of individuals of one learning style category, abstract sequential (AS), only three learning style categories were used in the study. Second, they completed a background information sheet. Third, they participated in the voice-input training and dictation phase. Each student completed a one-hour session that included training, practice using voice input, and dictating a paragraph. Participants also completed the Attitude Toward Voice Input Scale developed by the researcher. It includes 21 attitude statements, 11 positively worded and 10 negatively worded. The first hypothesis was not rejected. A student's learning style does not relate to the performance of the student when dictating a paragraph using voice input technology. The second hypothesis was not rejected either. A student's attitude toward voice input technology was not related to learning style. The third hypothesis was also not rejected. A student's learning style, regardless of whether the student had a "high" or "low" attitude toward voice input, was not significantly related to performance in using voice input technology. However, the mean performance scores of individuals with concrete sequential (CS) learning styles with "high" and "low" attitudes did appear to be different. Those with "high" attitudes toward voice input had better performance scores than those with "low" attitudes toward the technology. / Ph. D.

Most modern control systems use digital controllers to ensure safe operation. We modify the traditional digital control system architecture to integrate a new component known as a trusted input/output processor (TIOP). TIOP interface to the inputs (sensors) and outputs (actuators) of the system through existing communication protocols. The TIOP also interface to the application processor (AP) through a simple message passing protocol. This removes any direct input/output (I/O) interaction from taking place in the AP. By isolating this interaction from the AP, system resilience against malware is increased by enabling the ability to insert run-time monitors to ensure correct operation within provided safe limits. These run-time monitors can be located in either the TIOP(s) or in independent hardware. Furthermore, monitors have the ability to override commands from the AP should those commands seek to violate the safety requirements of the system. By isolating I/O interaction, formal methods can be applied to verify TIOP functionality, ensuring correct adherence to the rules of operation. Additionally, removing sequential I/O interaction in the AP allows multiple I/O operations to run concurrently. This reduces I/O latency which is desirable in many control systems with large numbers of sensors and actuators. Finally, by utilizing a hierarchical arrangement of TIOP, scalable growth is efficiently supported. We demonstrate this on a Xilinx Zynq-7000 programmable system-on-chip device. / Master of Science / Complex modern systems, from unmanned aircraft system to industrial plants are almost always controlled digitally. These digital control systems (DCSes) need to be verified for correctness since failures can have disastrous consequences. However, proving that a DCS will always act correctly can be infeasible if the system is too complex. In addition, with the growth of inter-connectivity of systems through the internet, malicious actors have more access than ever to attempt to cause these systems to deviate from their proper operation. This thesis seeks to solve these problems by introducing a new architecture for DCSes that uses isolated components that can be verified for correctness. In addition, safety monitors are implemented as a part of the architecture to prevent unsafe operation.

A major design aspect of touch tablet operation is the display/control (D/C) gain. The primary objective of this research was the development and optimization of a variable D/C gain to improve human performance with touch tablets. This variable gain minimizes the speed-accuracy trade-off problem associated with traditional D/C gains. An additional objective.of this research was to determine the effect of tablet size on human performance. Display/control (D/C) gain is defined as the amount of movement which occurs on the display in response to a unit amount of movement of the control. With traditional D/C gains, there is a trade-off between low D/C gain which enables fine positioning, but results in very slow cursor movement, and high D/C gain which produces quick cursor movement but results in poor fine positioning ability. A lead-lag compensator which ameliorates this trade-off problem was developed. A lead-lag compensator is composed of a pure position gain component plus an additional velocity gain component. The results indicate that a lead-lag compensator greatly increased the target acquisition rate relative to a traditional D/C gain system. Percentage error increased with lead-lag compensation relative to an uncompensated system. The overall error rates were very low in all cases, however. Tablet size did not appear to significantly affect performance; performance on the three tablet sizes was generally consistent. / M.S.

Economic input-output (I-O) and watershed models provide useful results but when seeking to integrate these systems, the structural, spatial, and temporal differences between these models must be carefully considered. To reconcile these differences, a hydrologic-economic modeling framework is designed to couple an economic model with a watershed model. A physically constrained, I-O model, RCOT, is used to represent the economic system in this framework because it provides sectoral detail for a regional economy and calculates physical resource quantities used by these sectors. Uniquely, it also allows for technology options for all sectors and minimizes the resource use based on environmental constraints imposed by the watershed, which adds complexity to the representation of the economic system and its interactions with the watershed system. To represent the watershed system in this framework, the Hydrological Simulation Program-Fortran (HSPF) is used. An HSPF model has been calibrated to represent the hydrological processes of Cedar Run Watershed by the Occoquan Watershed Monitoring Laboratory (OWML). Thus, the capabilities of this framework are demonstrated using strategic scenarios developed to examine future development patterns that may occur within Fauquier County, northern Virginia, and its local basin, Cedar Run Watershed. The scenarios evaluate both the downstream and seasonal impacts on water flow and nitrogen concentration within the watershed, and the changes made within the economic system in response to these impacts. For these scenarios, the most efficient solution is the one that minimizes the use of resource inputs within the economic sectors, including developed land, water withdrawn, and applied nitrogen, which in turn inform watershed health. The scenario results demonstrate that this coupled hydrologic-economic modeling framework can overcome the spatial differences of the individual models and can capture the interactions between watershed and economic systems at a temporal resolution that expands the types of questions one can address beyond those that can be analyzed using these models separately. / Doctor of Philosophy / Water is an essential commodity for human survival, a necessary resource for many industries, and a crucial indicator of environmental health. Rising human populations have created stress on the natural supply of water resources while corresponding economic activities have contributed to the deterioration in water quality. Therefore, it is essential to identify pathways for addressing water use and contamination while also supporting economic progress to achieve sustainable development. The region of study is Fauquier County, located in northern Virginia, USA. This county has a long association with agricultural production, but it has been experiencing development pressure due to its proximity to Washington DC (50 km southwest). Within Fauquier County lies Cedar Run Watershed (498 km2), a sub-basin of Occoquan Watershed (1,515 km2). Occoquan Watershed drains into the Occoquan Reservoir, which is a drinking water source for close to two million residents in northern Virginia. The motivation of this research is to design a coupled modeling framework that allows insight to be gained into the interactions that occur between watershed and economic systems. This framework is then used to evaluate how changes in economic activities will cause changes in water use and contamination levels within Cedar Run Watershed and vice versa. By designing strategic scenarios to provide implications about future development patterns that may occur in the region, changes can be anticipated, and conclusions can be reached.