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Securing Smart Home Iot Applications Via Wireless Traffic Analysis
Get PDFHouseholders have widely used IoT security systems with the development of smart home applications. Wireless security cameras are integral components of IoT security systems used by many private homes. These cameras commonly employ motion sensors to identify something occurring in their fields of vision before recording and notifying the property owner of the activity. In this thesis, we discover that the motion-sensing action can disclose the camera's location through a novel wireless camera localization technique we call MotionCompass. In short, a user who aims to avoid surveillance can find a hidden camera by creating motion stimuli and sniffing wireless traffic for a response to that stimuli. With the motion trajectories within the motion detection zone, the user can then compute the camera's exact location. We develop an Android app to implement MotionCompass. Our extensive experiments using the developed app and 18 popular wireless security cameras demonstrate that MotionCompass can attain a mean localization error of around 5 cm in less than 140 seconds for cameras with one motion sensor. This localization technique builds upon existing work that detects the existence of hidden cameras to pinpoint their exact location and area of surveillance
Semiotic Analysis of Idolic Communication at the Core of the Oklahoma City Memorial Museum
Get PDFTraumatic events leave generational scars in communities around the world. In Oklahoma City, the bombing of the Alfred P. Murrah Federal Building on April 19, 1995 left deep scars. The community then banded together to create a memorial museum in honor of the victims. Many years later, the community still grieves the lives lost. The purpose of this thesis is to take a look at the trauma and magic found inside the Oklahoma City Memorial Museum utilizing semiotics and the dimensional accrual dissociation theory in an attempt to understand the signification of traumatic signs
A path towards general acceptance: the feasibility of massively parallel sequence technology, nomenclature, and statistical analysis in forensic casework
Get PDFThe forced adoption of technology: a qualitative study on television journalists’ adaptation during the Coronavirus pandemic through the lens of technological determinism
Get PDFThis study focuses on local news leaders and journalists who faced unique circumstances in 2020 due to lockdowns and various restrictions because of Covid-19. This historic period provided a unique opportunity to see how journalists react to the forced adoption of technology when nearly every newsroom was forced to adopt different methods to continue newsgathering. Findings showed managers and journalists alike want to create connections between coworkers, but found it awkward to connect through a new workplace culture based on transactional relationships where very few opportunities have arisen for emotional bonds. Technology acted as a bridge connecting coworkers to their job and each other. As the pandemic evolved, technology became more of a barrier preventing strong emotional connections.
Keywords: COVID-19, Journalism, managmen
Examining Meteorological Benefits of Rapid-Scan, Dual-Polarization, All-Digital Phased Array Radar Observations for Detecting Tornado Formation and Intensification
Get PDFPhased array radar (PAR) is widely considered the future for a replacement to the current operational radar network, NEXRAD. In particular, an all-digital operational PAR network offers a range of benefits including adaptive scanning techniques, higher temporal resolution especially via radar imaging modes, and denser vertical sampling to allow for more complete observations of severe hazard structure and evolution. This study focuses on the application of future operational phased array radar (PAR) systems to observe tornadoes and their formation. To best understand the benefits of a future all-digital operational PAR, we generate synthetic PAR observations from archived mobile rapid-scan observations collected by the Rapid X-band Polarimetric radar (RaXPol) to emulate typical operational radar ranges, PAR enabled scanning strategy effects, and NEXRAD and future possible PAR volumetric update times.
In this study, the synthetic PAR tool is applied to two datasets from RaXPol: the 24 May 2011 El Reno, Oklahoma, tornado and the 24 May 2016 Dodge City, Kansas, tornadoes. Range and azimuth averaging is applied over different windows to emulate different standoff ranges more comparable to operational, fixed-site radars. Using dealiased velocity data, we analyze the intensity of synthetic PAR tornado vortex signatures (TVSs) through a measure of the intensity of rotation (Delta-V) plotted as a function of time and height for each different standoff range. Despite increasingly coarse resolution, we find similar qualitative trends in the vertical evolution of TVS intensity even though the magnitude of Delta-V decreases. TVS intensification is found to occur in an ascending or simultaneous manner, even for data that has undergone spatial resampling to much longer standoff ranges (e.g., 80 km). Thus, it appears that detection of rapid TVS intensification occurring in an upward or simultaneous manner, as seen previously with mobile radars, can be used to detect tornadogenesis with future operational PARs. Additional work has focused on comparison of expected PAR revisit times in comparison to NEXRAD volume scan times. Update times of 60 s or faster are found enhance the data available to forecasters by better capturing critical evolution steps currently missed at NEXRAD update times (i.e., typical volume updates every 5–-6 min). However, at longer standoff ranges, a slight delay in observing the TVS intensification is found across tested temporal resolutions. We also observed some instances at longer standoff ranges where tornado-scale versus mesocyclone-scale TVS intensification may be occurring in different directions, particularly at 40 s and 5 min updates. Finally, we have analyzed the implementation of focusing, which shows promising results. Focusing could be used by an operational radar to enable updates faster than 60 s by targeted observations of specific storms or a region within a larger storm complex. Ultimately, through understanding the meteorological benefits from the synthetic PAR data, we should be able to contribute to improved planning for future all-digital operational PARs and warning decisions for tornadic storms
Beam Shear in Mild Reinforced Ultra-high-performance Concrete
Get PDFUltra-high-performance concrete (UHPC) is being utilized in bridge construction primarily for deck overlays and end-of-girder and beam repairs of deteriorated traditional concrete elements. UHPC has been used selectively in new construction to form full-sized structural members. Compared to conventional concrete, UHPC has the benefits of having higher compressive strength, being more ductile, and being self-consolidating. Because of these qualities, it can be used in very thin beams with shallower depths than a conventional concrete member could. Before it can be used on a larger scale more must be known about the failures that can occur. The current ACI Code (ACI 318-19 2019) places an upper limit on the compressive strength allowed in the shear capacity equation of 10,000 psi. UHPC can have strengths more than double this and may not behave as expected. The aim of this project was to quantify the shear capacity of UHPC beams. The testing regimen for this project included two conventional concrete beams and three UHPC beams. The mix for the conventional concrete was based on an Oklahoma Department of Transportation Class AA, having a compressive strength of approximately 9,000 psi. The UHPC followed the non-proprietary mix design develop at the University of Oklahoma, designated J3, which had a compressive strength of 17,000 psi.
The beam specimens tested were approximately a half-scale AASHTO Type B beam with some exaggerated proportions to better facilitate shear failure. All beams were of the same dimensions, having an overall depth of 16 in., an effective depth of 14.25 in., a web height of 8 in., and a web thickness of 2 in. A total beam length of 14 ft was chosen to allow for a 12-ft testing region under third-point loading. There were supports under the beam at 1 ft from each end and loading was applied 5 ft from each end, giving equivalent 4-ft uniform shearing
regions. All beams were fitted with a reinforcing cage having no shear reinforcement in the zones under shear. Longitudinal reinforcement included three #6 reinforcing bars. Each member was tested at 28 days to allow for full-strength development. The UHPC beams did not fail in shear. With approximately 4 in. of deflection, the beams exhibited significant flexural cracking and minor shear cracks. The maximum load for each UHPC specimen exceeded an equivalent shear capacity of over 9√′. From this research, it was concluded that the current ACI Code (2019) design guidance is insufficiently accurate and overly conservative for UHPC members, but more research is required
An analysis of the information content of radar detection
Get PDFThe availability of the electromagnetic spectrum (EMS) was an unseen issue in the past,
as there was sufficient spectrum access to suit the needs of its’ consumers. Today, the use
of the EMS has been become integrated within our daily lives. Applications varying from
civil infrastructure to automotive radar has readily consumed the spectrum to communicate,
sense, and interpret information. Given the inflation of spectrum use, it is important
that we investigate the amount of information and bandwidth that different spectrum-based
applications are using and how different parameters can impact spectrum use. Previous
work has identified the fundamental decision bound of pulse-Doppler radar, defined by the
Rayleigh range-Doppler resolution, of 1 decision per second per Hz of transmitted bandwidth
and has identified a Bayesian detection capacity expression.
In this thesis, a closed form expression is derived for detection capacity of radar, which
does not require a priori probabilities. Furthermore, detection capacity expressions for
multiple receivers and the use of M of N integration are also derived. These expressions
are used to analyze the information content of different commonly used radar detectors
for different assumptions. Another primary focus of this thesis was the analysis of the
information content of both fluctuating targets and cell averaging constant false alarm rate
(CA-CFAR). The novel analysis of these different radar/target assumptions show the effect
that radar detection has on the spectrum. Finally, detection bandwidth and transmit range
are connected to determine how signal-to-noise ratio can impact transmit range and spectral
usage
An Experimental, Modeling and Machine Learning Based Investigation of Stick-Slip Vibrations
No full textDrilling technologies have improved considerably since the first well drilled by Colonel E.L Drake in 1859. Drilling technologies enable us to safely drill complex well profiles with advanced downhole tools and sensors to reach target zones faster. However, some of the basic inefficiencies in the drilling system have been consistent with time. Drilling vibrations is just one such example. The process of drilling rock involves transfer of energy from the top drive motor to the bit. Naturally, vibrations are inevitable during drilling and cause a reduction in the rate of penetration. While the understanding and mitigation of drilling vibrations has improved, the complexity of drilling conditions has considerably increased as well. The study identifies the different modes of drilling vibrations and presents a comprehensive review of the different methodologies to study and investigate them.
The broad topics included in the study are:
a. Types of drilling vibrations and their effects on drillstring.
b. Mechanisms of failures induced by drilling vibrations and ways to mitigate them.
c. Detailed literature review, specifically gap analysis in cause, detecting and measuring
drilling vibrations with respect to experimental investigation.
d. Overview of drillstring mechanics concept related to drilling vibrations.
e. Review of techniques to mitigate drilling vibrations.
f. Compare and evaluate different data acquisition (sampling rates) concepts for vibration
evaluation with experimental results.
g. Definition and quantification of the stick slip vibrations.
h. Parametric analysis of stick-slip vibrations using experimental test setup.
i. Comparison of experimental and modeling results for examining stick-slip vibrations.
j. Data driven technique to classify vibration severity of stick slip vibrations.
With the above-mentioned different approaches taken to examine drilling vibrations, especially stick-slip vibrations, a deeper understanding of this severe form of torsional vibrations is achieved. With experimental results, it was observed that both drillstring properties (stiffness, inertia) and drilling properties (RPM, WOB, TOB etc.) influenced the severity of stick-slip vibrations downhole. PVC was observed to have the highest stick-slip severity out of different drillstring materials chosen due to its lower torsional stiffness. Additionally, the sampling rate of the measurements significantly impacted diagnostics of stick-slip vibrations. 10 Hz of sampling is the minimum operational sampling rate advised for reliable downhole vibration diagnostics. Moreover, 100 Hz is the ideal sampling rate for complete diagnostics of stick-slip vibrations. The modeling results were in tune with experimental results and provided a fast method to analyze sensitivity of properties such as drillstring stiffness, friction, well angle, bit aggressivity etc. After successfully characterizing stick-slip vibrations using modeling and experimental approach, classifiers were built using machine learning algorithms that were hugely successful in isolating severe downhole vibrations from mild ones. These models were trained on the high-resolution experimental datasets and the issues related to data quality for machine learning applications are also highlighted.
Overall, a comprehensive understanding of severe torsional vibrations has been gained in this study which can be used in the field for better diagnostics, characterization, and mitigation of stick- slip vibrations