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There is a rapidly growing demand for individuals in cybersecurity and a deficit of persons able to fill those roles. To help meet this need, students not majoring in computing can be utilized to fulfill this demand by exposing them to date mining, cybersecurity practices, and applications of these concepts in the field. This paper presents findings from a twenty-one-week program in which minority undergraduate college students all members of the Reserve Officer Training Coprs (ROTC), were taught computer programming, natural language processing, data visualization, and computer vision fundamentals. Midshipmen and cadets used their newly gained knowledge, teamwork, planning, and communication skills to develop a threat dectection prototype using publicly available social media data. Resuls from pre and post python assessments and post-program interviews that recorded participant attitudes and sefl-efficacy are reported to highlight the programs' effectiveness. 

This Research Full Paper presents a qualitative interview study on the effectiveness of a computing identity development listserv. The demand for diverse computing careers increases, yet African Americans continue to participate and succeed in computing fields proportionately less than their White and Asian counterparts. An individual’s computing identity can influence their performance and willingness to participate. The African American PhDs in Computer Science Listserv is an email listserv created to increase and maintain members’ sense of belonging, self-efficacy, and resilience in computing. Semistructured interviews of graduate student, faculty, and industry professional members were conducted to investigate how effective the listserv was at increasing and maintaining computing identity. Findings include decision making processes for joining, duration and dosage of interaction members partake, maintenance of computing resilience, members’ self-reflection, willingness to seek help, and attitudes towards computing. Recommendations were made about the listserv and if other African Americans in computing should join. Findings can be used to develop new approaches to supporting the computing identities of underrepresented groups. This paper is in conjunction with other papers in an extended case study on resilient identity development in African American computer scientists. 

To improve the academic and professional achievement of underrepresented minorities in computing, a newfound interest in innovative mentoring practices has captivated STEM education researchers. Studies suggest that virtual mentoring conversational agents can be leveraged across multiple platforms to provide supplemental mentorship, offsetting the lack of access to in-person mentorship in disadvantaged communities. A within-subjects mixed-method experiment was carried out to assess the usability of a mentoring conversational agent. Mobile interfaces (Twitter and SMS) were compared to each other and against a web-based embodied conversational agent (ECA). Results suggest that mobile interfaces are more usable than the web-based ECA. The findings from this study help to identify areas for improvement in virtual learning alternatives and other potential applications for pervasive conversational interfaces. 

Abstract Gravitational lensing by massive objects along the line of sight to the source causes distortions to gravitational wave (GW) signals; such distortions may reveal information about fundamental physics, cosmology, and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO-Virgo network. We search for repeated signals from strong lensing by (1) performing targeted searches for subthreshold signals, (2) calculating the degree of overlap among the intrinsic parameters and sky location of pairs of signals, (3) comparing the similarities of the spectrograms among pairs of signals, and (4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by (1) frequency-independent phase shifts in strongly lensed images, and (2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the nondetection of GW lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects. 

Abstract We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search and the Swift-BAT search, we calculate flux upper limits and present joint upper limits on the gamma-ray luminosity of each GW. Given these limits, we constrain theoretical models for the emission of gamma rays from binary black hole mergers. 

Abstract We search for gravitational-wave (GW) transients associated with fast radio bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project, during the first part of the third observing run of Advanced LIGO and Advanced Virgo (2019 April 1 15:00 UTC–2019 October 1 15:00 UTC). Triggers from 22 FRBs were analyzed with a search that targets both binary neutron star (BNS) and neutron star–black hole (NSBH) mergers. A targeted search for generic GW transients was conducted on 40 FRBs. We find no significant evidence for a GW association in either search. Given the large uncertainties in the distances of our FRB sample, we are unable to exclude the possibility of a GW association. Assessing the volumetric event rates of both FRB and binary mergers, an association is limited to 15% of the FRB population for BNS mergers or 1% for NSBH mergers. We report 90% confidence lower bounds on the distance to each FRB for a range of GW progenitor models and set upper limits on the energy emitted through GWs for a range of emission scenarios. We find values of order 10⁵¹–10⁵⁷erg for models with central GW frequencies in the range 70–3560 Hz. At the sensitivity of this search, we find these limits to be above the predicted GW emissions for the models considered. We also find no significant coincident detection of GWs with the repeater, FRB 20200120E, which is the closest known extragalactic FRB.