Wide-band doubler and sine wave quadrature generator

Phase-locked loop with photoresistive control, which provides both sine and cosine outputs for subcarrier demodulation, serves as a telemetry demodulator signal conditioner with a second harmonic signal for synchronization with the locally generated code

Frequency discriminator/phase detector

Circuit provides dual function of frequency discriminator/phase detector which reduces frequency acquisition time without adding to circuit complexity. Both frequency discriminators, in evaluated frequency discriminator/phase detector circuits, are effective two decades above and below center frequency

Filter for third order phase locked loops

Filters for third-order phase-locked loops are used in receivers to acquire and track carrier signals, particularly signals subject to high doppler-rate changes in frequency. A loop filter with an open-loop transfer function and set of loop constants, setting the damping factor equal to unity are provided

Cyber-Physical System Intrusion: A Case Study of Automobile Identification Vulnerabilities and Automated Approaches for Intrusion Detection

Today\u27s vehicle manufacturers do not tend to publish proprietary packet formats for the controller area network (CAN), a network protocol regularly used in automobiles and manufacturing. This is a form of security through obscurity -it makes reverse engineering efforts more difficult for would-be intruders -but obfuscating the CAN data in this way does not adequately hide the vehicle\u27s unique signature, even if these data are unprocessed or limited in scope. To prove this, we train two distinct deep learning models on data from 11 different vehicles. Our results clearly indicate that one can determine which vehicle generated a given sample of CAN data. This erodes consumer safety: a sophisticated attacker who establishes a presence on an unknown vehicle can use similar techniques to identify the vehicle and better format attacks. To protect critical cyber-physical systems (CPSs) against attacks like those enabled by this CAN vulnerability, system administrators often develop and employ intrusion detection systems (IDSs). Before developing an IDS, one requires an understanding of the behavior of the CPS and of the causality of its constituent parts. Such an understanding allows one to characterize normal behavior and, in turn, identify and report anomalous behavior. This research explores two different time series analysis techniques, Granger causality and empirical dynamic modeling (EDM), which may contribute to this understanding of a system. Our findings indicate that Granger causality is not a suitable approach to IDS development but that EDM may enable the understanding of a system required of an IDS architect. We thus encourage further research into EDM applications to IDSs for CPSs

T-PESS and Special Education Teacher Attrition and Retention: A Qualitative Phenomenological Study of Teacher Perceptions of Administrator Effectiveness

The purpose of this qualitative phenomenology study was to explore special education teacher retention in a large school district in Texas and the perception of campus principal’s support as defined through the domains from the Texas Principal Evaluation and Support System (T-PESS). Participants in the study came from 550 special education teachers in Desert ISD, a school district in North Texas. I completed semi-structured interviews with a minimum of three special education teachers from elementary, middle school, and high school levels