The aim of the work was to create an automatic positioning system, with optics for radiation concentration and a body for its collection, by monitoring the sun across the sky using a camera. At the beginning are introduced the concentrator systems and the movement of the sun from the perspective of the observer. Follows description of the various potential components which requires a functional system. The last part deal with the implementation of selected components for operation as a whole system, verification of functionality by accurate tracking of the sun across the sky and measuring the performance of the concentrator system with automatic positioning.

Thesis advisor: Eric S. Folker / Skeletal muscle is a syncytial cell type in which the multiple nuclei are evenly spaced along the cell periphery. During muscle development, the myonuclei undergo an elaborate set of movements to achieve this precise positioning throughout the muscle. The importance of proper nuclear positioning is highlighted by the correlation between mispositioned nuclei and muscle disease. However, the mechanisms that govern this energetically expensive process as well as the influence nuclear positioning has on muscle cell function remains to be elucidated. The goal of this thesis is to determine the molecular factors and subsequent mechanisms that regulate nuclear movement and how such pathways are disrupted in various muscle diseases. Since many of the key cellular features are conserved between Drosophila and mammalian muscles, we utilize Drosophila musculature as a model system to study myonuclear positioning during muscle development. In this thesis, we provide the first evidence that nuclei experience attractive and repulsive interactions with one another as they actively migrate. Furthermore, we demonstrate that these nucleus-nucleus interactions are critical for proper nuclear positioning, and that they are distinctly regulated by genes that are associated with two different muscle diseases, Emery-Dreifuss muscular dystrophy and Centronuclear myopathy (Chapter 2). We then elaborate upon the genetic mechanisms through which CNM-linked genes regulate nuclear positioning (Chapter 3). Finally, we show that proper nuclear movement requires both the separation of nuclei from their neighbors as well as the transmission of force, that is generated from the cytoskeleton, to move nuclei within the cell (Chapter 4). Together, the work presented in this thesis provides new perspective and mechanistic insights into the genetic factors and physical forces that regulate nuclear movement during muscle development and how such pathways are disrupted in disease, while emphasizing the importance of studying such dynamic processes within an in vivo system. / Thesis (PhD) — Boston College, 2020. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Biology.

<p>The need for an aviation navigation system is established from examining the phase out of current systems and the delay in the development of replacement systems. The systems engineering approach has been applied to ensure that a capable system is developed. After establishing the need, two GPS based methods of creating an aviation navigation system are examined. A system based on the differential GPS method is chosen as the most feasible.</p> <p> The functional analysis, operational requirements and maintenance concept are defined based on the differential GPS choice. A conceptual system design is then described for each system element, the ground beacon element and the aircraft element. The allocation of requirements, element architecture and element reliability are examined in the conceptual design.</p> / Master of Science

<p>With continuing advances in technology, the market for vehicle navigation systems is expected to grow over the next several years. The systems engineering process is applied to ensure that an effective system is developed. After the need is established, four methods of implementing a vehicle navigation system are described. A system employing differential GPS to determine the location of the vehicle is chosen to be the most feasible approach. Based on this choice, the operational requirements and maintenance concept are defined. Possible design approaches are then discussed. A terrestrial radio link is selected over a satellite link to transmit the differential corrections to users. Finally, an analysis is performed to estimate the number of reference stations that will be required to implement the system. The results can be used as a guideline to determine the potential cost of providing a differential GPS service.</p> / Master of Science

Global Navigation Satellite Systems (GNSS) is in widespread use around the world for numerous purposes. Even though it was first developed for military purposes, nowadays, the civilian use has surpassed it by far. It has evolved to its finest state in recent days and still being developed further towards pinpoint accuracy. With all the improvements, several vulnerabilities have been discovered by researchers and exploited by the attackers. Several countermeasures have been and still being implemented to secure the GNSS. Studies show that GNSS-based receivers are still vulnerable to a very fundamentally simple, yet effective, attack; known as the replay attack. The replay attack is particularly harmful since the attacker could make the receiver calculate an inaccurate position, without even breaking the encryption or without employing any sophisticated technique. The Multiple Combinations of Satellites and Systems (MCSS) test is a powerful test against replay attacks on GNSS. However, detecting and identifying multiple attacking signals and determining the correct position of the receiver simultaneously remain as a challenge. In this study, after the implementation of MCSS test, a mechanism to detect the attacker controlled signals has been demonstrated. Furthermore, applying a clustering algorithm on the product of MCSS test, a method of correctly determining the position, nullifying the adversarial effects has also been presented in this report.

This dissertation is an examination of the ways English teachers may be complicit in reproducing an abstinence-based sex education discourse in their own classroom practices and discussions of literature. Working from disciplinary research in sex education, sociology, English education, anthropology, and public health, I explore English teachers\' experiences in negotiating the effects of, reactions to, and expectations for discussing sexuality, intimacy, and gender in a school community. Using feminist positioning theory and Bakhtin\'s concepts of dialogism and ventriloquism, I explore how teachers approach, grapple with, contribute to, and leverage dominant institutional discourses in their practices, thereby mediating knowledge, possibilities for conversations, and institutional norms. An amalgam of teaching philosophies, methodologies, and political ideologies underscores teachers\' voicing patterns and discursive positions, helping to further inform an understanding of how contentious social issues are negotiated in the classroom. The agentic discursive positions teachers take up provide insights into teachers as mediating agents within institutional discourses, but not necessarily as change agents of institutional norms. / Ph. D.

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Data from a Coarse Acquisition (C/A) Global Positing System (GPS) map-grade receiver were evaluated to assess the accuracy of differentially corrected points. Many studies have focused on the accuracy of GPS units under ideal data collection conditions. Ideal conditions allow the collection of data with four satellites (3D mode), yet field data conditions are often less than ideal. Four satellites may not always be in view because of mountainous topography, heavy forest cover, or other obstructions which block satellite signals from the receiver. This study examines GPS accuracy when four satellites are not available, instead collecting data with only three satellites (2D mode). 3D GPS points compute four unknowns: x, y , z, and clock error. In comparison, 2D GPS points are less accurate as only three unknowns are calculated: x, y, and clock error. Elevation (or z) is not computed for 2D points, causing increased error in the horizontal (x, y) measurement. The effect of elevation was evaluated on 234 2D GPS data points. These points were collected and corrected at elevation intervals of true elevation, +-25 meters, +- 50 meters, and +-75 meters. These 2D points were then compared to surveyed points to measure the effect vertical error has on horizontal accuracy. In general, the more error in the vertical estimate during correction, the greater the horizontal error. / Master of Science

The development of an Indoor Positioning System that requires a non-invasive setup and installation process is outlined in this dissertation. The Hardware, Mechanical and Software components are described in complete detail. The system operates using a hybrid of Bluetooth Low Energy (BLE) signal strength analysis and proximity sensor data collection to determine the location of a known Bluetooth compatible device. Additionally, a dynamic remote calibration protocol was developed to ensure a safe and smooth setup and integration process in any location the system is implemented. The system uses custom designed beacon modules that connect directly to outlets in designated rooms. These beacons relay sensor and BLE data to a Hub module that collects and stores all this data locally and on a cloud server. These features ensured that the IPS is a completely remote device that can be setup independently by the user. To our knowledge, this is the only Indoor Positioning System that does not require prior knowledge of the location of integration and the need for an in-person setup and calibration process. Additionally, despite the lack of an extensive setup and calibration process the system still operates at an accurate room detection percentage of 98%. To further prove its ease of use the system has been implemented in a clinical study where several older adults (65+) have integrated this system within their homes. This system has been designed to act as the foundation for larger scale healthcare monitoring applications. / Thesis / Candidate in Philosophy / Indoor positioning technology acts as the foundation for several healthcare monitoring networks. An accurate and easy to use indoor positioning system will entail how effective the overall healthcare monitoring platform is. Additionally, indoor positioning itself can be accomplished in several different ways. Some of these approaches include the use of physical sensors to detect presence, signal strength approximations via some sort of communication protocol or even the use of secure entry via RFID identification tags. Currently, most of the systems that use one of these approaches require extensive setup and calibration processes and extensive knowledge of the tracking locations. However, this is not always practical especially when the system is integrated in a large-scale environment like a retirement home. A system with an easy- to-use setup and installation platform is needed to complete these high impact healthcare monitoring projects.