Radiation effects encountered in space or aviation environments can affect the configuration bits in Field Programmable Gate Arrays (FPGA) causing errors in FPGA output. One method of increasing FPGA reliability in radiation environments includes adding redundant logic to mask errors and allow time for repair. Despite the redundancy added with triple modular redundancy (TMR) and configuration scrubbing there exist some configuration bits that individually affect multiple TMR domains causing errors in FPGA output. A new tool called DeBit is introduced that identifies hardware resources associated with a single bit failure. This tool identifies a novel failure mode involving global routing resources and the failure mode is verified through a series of directed tests on global routing resources. Lastly, a mitigation strategy is proposed and tested on a single error in a triple modular redundancy (TMR) design.

Radiation effects encountered in space or aviation environments can affect the configuration bits in Field Programmable Gate Arrays (FPGA) causing errors in FPGA output. One method of increasing FPGA reliability in radiation environments includes adding redundant logic to mask errors and allow time for repair. Despite the redundancy added with triple modular redundancy (TMR) and configuration scrubbing there exist some configuration bits that individually affect multiple TMR domains causing errors in FPGA output. A new tool called DeBit is introduced that identifies hardware resources associated with a single bit failure. This tool identifies a novel failure mode involving global routing resources and the failure mode is verified through a series of directed tests on global routing resources. Lastly, a mitigation strategy is proposed and tested on a single error in a triple modular redundancy (TMR) design.

In this small-scale qualitative study we examine PowerPoint presentations using cognitive perspectives (such as the Cognitive Theory of Multimedia Learning, Arousal theory, and Dual Channel processing) to compare teacher experience with a theoretical background. By analyzing collected PowerPoint presentations and interviewing the experienced teachers that created them about their didactic choices, we are able to identify and focus on four aspects of multimedia learning: Pacing, Student Stimuli, Signaling and Redundancy. Although the teachers involved in the study do not reference the cognitive perspective explicitly, we find similarities and differences between the teachers' near-practice experience and the underlying cognitive theories, finding pedagogical value in both their complementary and contradictory natures. From this, we suggest that the principles of cognitive theories from a scientific basis are complemented and tempered by the flexibility of experience.

The quality aspect of mechanical components is a significant factor forcustomer satisfaction. By increasing the robustness, the product will be moreresistant to non-ideal situations and the perceived quality would be increased.A concept design for the case of A-Stay mounting on articulated haulers isdeveloped to increase the robustness of the product and removing the risk formechanical failure. A modified product development process with focus onaspects of assembly and robust design is used to generate concepts anddeveloping a concept design. The process resulted in a concept that increasesthe robustness of the system, both through higher redundancy and improvedcontrol of the noise factors.

A diagnosis procedure is an algorithm to detect and locate (isolate) faulty components in a dynamic process. In 1994 the California Air Resource Board released a regulation, called OBD II, demanding a thorough diagnosis system on board automotive vehicles. These legislative demands indicate that diagnosis will become increasingly important for automotive engines in the next few years. To achieve diagnosis, redundancy has to be included in the system. This redundancy can be either hardware redundancy or analytical redundancy. Hardware redundancy, e.g. an extra sensor or extra actuator, can be space consuming or expensive. Methods based on analytical redundancy need no extra hardware, the redundancy here is generated from a process model instead. In this thesis, approaches utilizing analytical redundancy is examined. A literature study is made, surveying a number of approaches to the diagnosis problem. Three approaches, based on both linear and non-linear models, are selected and further analyzed and complete design examples are performed. A mathematical model of an SI-engine is derived to enable simulations of the designed methods.

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This thesis presents model-based adaptive motion control algorithms for under-actuated aerial robotic manipulators combining a conventional multi-rotor Unmanned Aerial Vehicle (UAV) and a multi-link serial robotic arm. The resulting control problem is quite challenging due to the complexity of the combined system dynamics, under-actuation, and possible kinematic redundancy. The under-actuation imposes second-order nonholonomic constraints on the system motion and prevents independent control of all system degrees of freedom (DOFs). Desired reference trajectories can only be provided for a selected group of independent DOFs, whereas the references for the remaining DOFs must be determined such that they are consistent with the motion constraints. This restriction prevents the application of common model-based control methods to the problem of this thesis. Using insights from the system under-actuated dynamics, four motion control strategies are proposed which allow for semi-autonomous and fully-autonomous operation. The control algorithm is fully developed and presented for two of these strategies; its development for the other two configurations follows similar steps and hence is omitted from the thesis. The proposed controllers incorporate the combined dynamics of the UAV base and the serial arm, and properly account for the two degrees of under-actuation in the plane of the propellers. The algorithms develop and employ the second-order nonholonomic constraints to numerically determine motion references for the dependent DOFs which are consistent with the motion constraints. This is a unique feature of the motion control algorithms in this thesis which sets them apart from all other prior work in the literature of UAVmanipulators. The control developments follow the so-called method of virtual decomposition, which by employing a Newtonian formulation of the UAV-Manipulator dynamics, sidesteps the complexities associated with the derivation and parametrization of a lumped Lagrangian dynamics model. The algorithms are guaranteed to produce feasible control commands as the constraints associated with the under-actuation are explicitly considered in the control calculations. A method is proposed to handle possible kinematic redundancy in the presence of second-order motion constraints. The control design is also extended to include the propeller dynamics, for cases that such dynamics may significantly impact the system response. A Lyapunov analysis demonstrates the stability of the overall system and the convergence of the motion tracking errors. Experimental results with an octo-copter integrated with a 3 DOF robotic manipulator show the effectiveness of the proposed control strategies. / Thesis / Doctor of Philosophy (PhD)

Unification in Description Logics has been proposed as a novel inference service that can, for example, be used to detect redundancies in ontologies. The inexpressive Description Logic EL is of particular interest in this context since, on the one hand, several large biomedical ontologies are defined using EL. On the other hand, unification in EL has recently been shown to be NP-complete, and thus of considerably lower complexity than unification in other DLs of similarly restricted expressive power. However, EL allows the use of the top concept (>), which represents the whole interpretation domain, whereas the large medical ontology SNOMEDCT makes no use of this feature. Surprisingly, removing the top concept from EL makes the unification problem considerably harder. More precisely, we will show that unification in EL without the top concept is PSpace-complete. / This is an updated version of the original report that includes Appendix A on locality of unifiers.

Data sensing and retrieval in WSNs have a great applicability in military, environmental, medical, home and commercial applications. In query-based WSNs, a user would issue a query with QoS requirements in terms of reliability and timeliness, and expect a correct response to be returned within the deadline. Satisfying these QoS requirements requires that fault tolerance mechanisms through redundancy be used, which may cause the energy of the system to deplete quickly. This dissertation presents the design and validation of adaptive fault tolerant QoS control algorithms with the objective to achieve the desired quality of service (QoS) requirements and maximize the system lifetime in query-based WSNs. We analyze the effect of redundancy on the mean time to failure (MTTF) of query-based cluster-structured WSNs and show that an optimal redundancy level exists such that the MTTF of the system is maximized. We develop a hop-by-hop data delivery (HHDD) mechanism and an Adaptive Fault Tolerant Quality of Service Control (AFTQC) algorithm in which we utilize "source" and "path" redundancy with the goal to satisfy application QoS requirements while maximizing the lifetime of WSNs. To deal with network dynamics, we investigate proactive and reactive methods to dynamically collect channel and delay conditions to determine the optimal redundancy level at runtime. AFTQC can adapt to network dynamics that cause changes to the node density, residual energy, sensor failure probability, and radio range due to energy consumption, node failures, and change of node connectivity. Further, AFTQC can deal with software faults, concurrent query processing with distinct QoS requirements, and data aggregation. We compare our design with a baseline design without redundancy based on acknowledgement for data transmission and geographical routing for relaying packets to demonstrate the feasibility. We validate analytical results with extensive simulation studies. When given QoS requirements of queries in terms of reliability and timeliness, our AFTQC design allows optimal "source" and "path" redundancies to be identified and applied dynamically in response to network dynamics such that not only query QoS requirements are satisfied, as long as adequate resources are available, but also the lifetime of the system is prolonged. / Ph. D.

Implementation of the Clean Water Act requires agencies to monitor aquatic sites on a regular basis and evaluate the quality of these sites. Sites are evaluated individually even though there may be numerous sites within a watershed. In some cases, sampling frequency is inadequate and the evaluation of site quality may have low reliability. This dissertation evaluates testing procedures for determination of site quality based on modelbased procedures that allow for other sites to contribute information to the data from the test site. Test procedures are described for situations that involve multiple measurements from sites within a region and single measurements when stressor information is available or when covariates are used to account for individual site differences. Tests based on analysis of variance methods are described for fixed effects and random effects models. The proposed model-based tests compare limits (tolerance limits or prediction limits) for the data with the known standard. When the sample size for the test site is small, using model-based tests improves the detection of impaired sites. The effects of sample size, heterogeneity of variance, and similarity between sites are discussed. Reference-based standards and corresponding evaluation of site quality are also considered. Regression-based tests provide methods for incorporating information from other sites when there is information on stressors or covariates. Extension of some of the methods to multivariate biological observations and stressors is also discussed. Redundancy analysis is used as a graphical method for describing the relationship between biological metrics and stressors. A clustering method for finding stressor-response relationships is presented and illustrated using data from the Mid-Atlantic Highlands. Multivariate elliptical and univariate regions for assessment of site quality are discussed. / Ph. D.