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Safeguards for Uranium Extraction (UREX) +1a ProcessFeener, Jessica S. 2010 May 1900 (has links)
As nuclear energy grows in the United States and around the world, the expansion
of the nuclear fuel cycle is inevitable. All currently deployed commercial reprocessing
plants are based on the Plutonium - Uranium Extraction (PUREX) process. However,
this process is not implemented in the U.S. for a variety of reasons, one being that it is
considered by some as a proliferation risk. The 2001 Nuclear Energy Policy report
recommended that the U.S. "develop reprocessing and treatment technologies that are
cleaner, more efficient, less waste-intensive, and more proliferation-resistant." The
Uranium Extraction (UREX+) reprocessing technique has been developed to reach these
goals. However, in order for UREX+ to be considered for commercial implementation, a
safeguards approach is needed to show that a commercially sized UREX+ facility can be
safeguarded to current international standards.
A detailed safeguards approach for a UREX+1a reprocessing facility has been
developed. The approach includes the use of nuclear material accountancy (MA),
containment and surveillance (C/S) and solution monitoring (SM). Facility information
was developed for a hypothesized UREX+1a plant with a throughput of 1000 Metric
Tons Heavy Metal (MTHM) per year. Safeguard goals and safeguard measures to be
implemented were established. Diversion and acquisition pathways were considered;
however, the analysis focuses mainly on diversion paths. The detection systems used in
the design have the ability to provide near real-time measurement of special fissionable
material in feed, process and product streams. Advanced front-end techniques for the
quantification of fissile material in spent nuclear fuel were also considered. The
economic and operator costs of these systems were not considered. The analysis shows
that the implementation of these techniques result in significant improvements in the
ability of the safeguards system to achieve the objective of timely detection of the diversion of a significant quantity of nuclear material from the UREX+1a reprocessing
facility and to provide deterrence against such diversion by early detection.
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Evaluation of FMCW Radar Jamming SensitivitySnihs, Ludvig January 2023 (has links)
In this work, the interference sensitivity of an FMCW radar has been evaluated by studying the impact on a simulated detection chain. A commercially available FMCW radar was first characterized and its properties then laid the foundation for a simulation model implemented in Matlab. Different interference methods have been studied and a selection was made based on the results of previous research. One method aims to inject a sufficiently large amount of energy in the form of pulsed noise into the receiver. The second method aims to deceive the radar into seeing targets that do not actually exist by repeating the transmitted signal and thus giving the radar a false picture of its surroundings. The results show that if it is possible to synchronize with the transmitted signal then repeater jamming can be effective in misleading the radar. In one scenario the false target even succeeded in hiding the real target by exploiting the Cell-Averaging CFAR detection algorithm. The results suggests that without some smart countermeasures the radar has no way of distinguishing a coherent repeater signal, but just how successful the repeater is in creating a deceptive environment is highly dependent on the detection algorithm used. Pulsed noise also managed to disrupt the radar and with a sufficiently high pulse repetition frequency the detector could not find any targets despite a simulated object in front of the radar. On the other hand, a rather significant effective radiated power level was required for the pulse train to achieve any meaningful effect on the radar, which may be due to an undersampled signal in the simulation. It is therefore difficult based on this work to draw any conclusions about how suitable pulsed noise is in a non-simulated interference context and what parameter values to use.
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Channel Probing for an Indoor Wireless Communications ChannelHunter, Brandon 13 March 2003 (has links) (PDF)
The statistics of the amplitude, time and angle of arrival of multipaths in an indoor environment are all necessary components of multipath models used to simulate the performance of spatial diversity in receive antenna configurations. The model presented by Saleh and Valenzuela, was added to by Spencer et. al., and included all three of these parameters for a 7 GHz channel. A system was built to measure these multipath parameters at 2.4 GHz for multiple locations in an indoor environment. Another system was built to measure the angle of transmission for a 6 GHz channel. The addition of this parameter allows spatial diversity at the transmitter along with the receiver to be simulated. The process of going from raw measurement data to discrete arrivals and then to clustered arrivals is analyzed. Many possible errors associated with discrete arrival processing are discussed along with possible solutions. Four clustering methods are compared and their relative strengths and weaknesses are pointed out. The effects that errors in the clustering process have on parameter estimation and model performance are also simulated.
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