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We employ a stochastic approach that models spacetime fluctuations close to the Planck scale by means of a classical, randomly fluctuating metric (random gravity framework).  We enrich the classical scheme for metric perturbations over a curved background by also including matter fields and metric conformal fluctuations.  We show in general that a conformally modulated metric induces dephasing as a result of an effective nonlinear Newtonian potential obtained in the appropriate non-relativistic limit of a minimally coupled Klein-Gordon field.  The special case of vacuum fluctuations is considered and a quantitative estimate of the expected effect deduced. Secondly, we address the question of how conformal fluctuations could physically arise.  By applying the random gravity framework we first show that standard GR seems to forbid spontaneous conformal metric modulations.  Finally we argue that a different result follows within scalar-tensor theories of gravity such as e.g. Brans-Dicke theory. In this case a conformal modulation of the metric arises naturally as a result of the fluctuations in the Brans-Dicke field and quantum dephasing of a test particle is expected to occur.  For large negative values of the coupling parameter the conformal fluctuations may also contribute to alleviate the well known problem of the large zero point energy due to quantum matter fields.

The thesis summarizes a selection of my research within Synthetic Aperture Radar (SAR). Mainly the research is aimed at applying and developing signal processing methods to single channel and multi channel SAR for wideband systems. SAR systems can generate images looking very similar to optical pictures, i.e. photos, and sometimes with much finer resolution compared to optical systems orbiting Earth. SAR has also for instance been used to obtain fine resolution images of the moon, Venus and the satellites of Saturn. Other applications for SAR has is to detect changes in ice sheets and deforestation. In this thesis, SAR systems capable of very high resolution imaging are con- sidered, and data from such systems, namely the VHF system CARABAS-II and the UHF system LORA, is used. High resolution imaging in this thesis refers to high resolution with regard to wavelength, this independent of system operating frequency. Two of the topics in this thesis are related to detection and parameter estimation of moving objects in SAR, the first one using CARABAS-II data and the second with LORA data. On the CARABAS-II data, a speed estimation and refocusing method is introduced and applied to single channel CARABAS-II data. The results show good estimation accuracy as well as good ability to focus the object and suppress forest clutter by ap- plying the refocusing algorithm. The results on LORA data are satisfactory especially with regard to forest clutter suppression. The ability to detect and focus images of ships allow for surveillance of coastal areas and help in rescue of ships lost at sea. Detection and location of cars and trucks allow for traffic monitoring to obtain statistics of how many cars travel the roads and their speed. In the thesis, two more important aspects for SAR processing is presented. One paper presents windowing of UWB SAR images. A strong object such as a power line in a SAR image cause ringing on both sides of the power line. This ringing can cause a small house to be covered by these so called side lobes. Applying a window can make these side lobes in the image much suppressed, however if windowing too much, the power line will smear over the image, covering the small house. The last topic in the thesis concern with theoretical limits for measurement accuracy of parameters for a moving object in a SAR image. These parameters are position, velocity, radar cross section and phase. The theoretical expressions are verified using simulations for a single channel system for estimation accuracy of target speed and relative speed.

The majority of adolescents in the United States do not obtain the recommended amount of sleep each night. While the reasons for this are multi-factorial, early school start times effect the amount of sleep an adolescent is able to achieve each night. Biological rhythms influence adolescents to stay up later and wake up later in the morning. School districts across the country are taking notice of adolescent sleep research and delaying their start times to better match adolescents' biological rhythms. However, the majority of the schools in the United States continue to start earlier than the recommended 8:30am start time, including the school district targeted in this project. The purpose of this project was to collect data from administrators whose schools had undergone a delay in school start time on the barriers and facilitating factors they found during the implementation. This information was then shared with the local school district.

Wind power is one of the most promising renewable energy resources to replace conventional generation which carries high carbon footprints. Due to the abundance of wind and its relatively cheap installation costs, it is likely that wind power will become the most important energy resource in the near future. The successful development of wind power relies heavily on the ability to integrate wind power effciently into electricity grids. To optimize the value of wind power through careful power dispatches, techniques in forecasting the level of wind power and the associated variability are critical. Ideally, one would like to obtain reliable probability density forecasts for the wind power distributions. As wind is intermittent and wind turbines have non-linear power curves, this is a challenging task and many ongoing studies relate to the topic of wind power forecasting. For this reason, this thesis aims at contributing to the literature on wind power forecasting by constructing and analyzing various time series models and spatiotemporal models for wind power production. By exploring the key features of a portfolio of wind power data from Ireland and Denmark, we investigate different types of appropriate models. For instance, we develop anisotropic spatiotemporal correlation models to account for the propagation of weather fronts. We also develop twostage models to accommodate the probability masses that occur in wind power distributions due to chains of zeros. We apply the models to generate multi-step probability forecasts for both the individual and aggregated wind power using extensive data sets from Ireland and Denmark. From the evaluation of probability forecasts, valuable insights are obtained and deeper understanding of the strengths of various models could be applied to improve wind power forecasts in the future.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Currently, there is a large effort being placed on the use of commercial-off-the-shelf (COTS) equipment to satisfy dedicated system requirements. This emphasis is being pursued in the quest of reducing overall system development costs. The development activity discussed in this paper consisted of determining some of the boundaries and constraints in the use of COTS equipment for high speed data distribution. This paper will present some of the lessons learned in developing a real-time high speed (greater than 1 MByte/sec) data distribution subsystem using COTS equipment based on industry accepted standards and POSIX P1003.1 operating system compliance.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Functional integration and validation of complex systems in an operational environment, prior to delivery or installation, can be expensive. Real-time simulation, in a lab environment, can replace hardware subsystems to provide the interfaces necessary to validate and or integrate the test article. The test article can be hardware, software or firmware. Multitasking simulations can provide modeling of subsystems and environmental sensor data for complex system integration. The simulation presented provides the capability to integrate 1553 remote terminals and provide validation of 1553 bus controller software.

International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / Real-time high-volume telemetry data analysts have needs which require access to ever-increasing amounts of data, which must be processed in a seamless and coherent manner. BBN has developed a data analysis software architecture for use in distributed- and parallel-processing environments which is particularly well-suited for telemetry streams. BBN is currently using this software at two Navy sites to do realtime data analysis. The architecture provides data-source management, data-stream fusion, and data extraction all in a modular, scalable framework. Because of the scalable nature of the software, it can easily accommodate high data rates.