Making Evildoers Pay: Resource-Competitive Broadcast in Sensor Networks

Consider a time-slotted, single-hop, wireless sensor network (WSN) consisting of n correct devices and and t=f*n Byzantine devices where f>=0 is any constant; that is, the Byzantine devices may outnumber the correct ones. There exists a trusted sender Alice who wishes to deliver a message m over a single channel to the correct devices. There also exists a malicious user Carol who controls the t Byzantine devices and uses them to disrupt the communication channel. For a constant k>=2, the correct and Byzantine devices each possess a meager energy budget of O(n^{1/k}), Alice and Carol each possess a limited budget of \tilde{O}(n^{1/k}), and sending or listening in a slot incurs unit cost. This general setup captures the inherent challenges of guaranteeing communication despite scarce resources and attacks on the network. Given this Alice versus Carol scenario, we ask: Is communication of m feasible and, if so, at what cost? We develop a protocol which, for an arbitrarily small constant \epsilon>0, ensures that at least (1-\epsilon)n correct devices receive m with high probability. Furthermore, if Carol's devices expend T energy jamming the channel, then Alice and the correct devices each spend only \tilde{O}(T^{1/(k+1)}). In other words, delaying the transmission of m forces a jammer to rapidly deplete its energy supply and, consequently, cease attacks on the network

Amplification and Filtering Stage for An In-Home Wireless Polysomnograph

Obstructive sleep apnea is a sleep disorder that tends to be easily treatable but, for most sufferers, is undiagnosed. To lower the economic barriers to screening the design of a portion of a polysomnograph, or obstructive sleep apnea testing tool, is considered. A filtering and amplification stage is theorized, simulated, and constructed for testing. The stage, consisting of three cascaded 1st order Butterworth low pass filters and amplifiers, did not achieve the target signal to noise ratio for a sinusoidal waveform of amplitude 200µv, but showed promising signal to noise ratios for waveforms with amplitudes as low as 600µv. The stage was then designed for implementation on a printed circuit board such that the noise mitigation techniques of printed circuit board implementation would allow successful signal to noise ratios to be achieved

The Myth of Promiscuity: Examining Black Male Sexual Narratives and Sexual Identity

Black masculinity and sexuality are common topics across areas of philosophy, psychology, cultural studies and others. Yet, these topics are dedicated to the racial narrative of hypersexual Black male, the sexual objectification of Black men, and their presumed promiscuity. While such topics are important, there is little qualitative research that looks at the complexity and emotionality of African American men’s sexual experiences. Using the theoretical research on black masculinity and sexuality as its backdrop, this dissertation explores how heterosexual, African American men experience their sexuality. The study incorporates narrative inquiry and in-depth, semi-structured interviews to gather stories of five African American men. This study also uses an autoethnography from the researcher to answer the research question and extensively consider how his experiences as a Black man influence the project. All provided narratives are analyzed through a narrative performance analysis and an interactional analysis. The results illustrate the multifaceted, complex, and conflicted experiences of sexuality. Namely, the participants\u27 experiences are framed through the historical, social, cultural, and personal constructions of blackness. Likewise, the results highlight the depth of these experiences, demonstrating the sexuality extended beyond sexual intercourse and pertained to how the participants understood and their relationships to others. This dissertation highlights five important themes that are apparent in the participants’ stories. First, the participants experience a sense of exhaustion after being constantly filtered through a racial narrative of hypersexuality. The men indicate different moments when problematic, reductive, and objectifying interpretations restrict their sense of self. Second, the participants’ stories highlight an alienating and dehumanizing sense of fragmentation in predominantly White spaces. Third, The participants note experiences of anxiety and vigilance because they were uncertain of how people saw them. Fourth, the participants state that people sexually objectify and reduce them to their penises which also highlights a loss of their bodies and inner lives. Fifth, participants attempt to use their insights into their experiences to regain a sense of agency and strengthen their self-confidence. While this often includes a reification of some racialized stereotypes, they attempt to define sexuality on their own terms though success varied between them

The Role of Educational Institutions for Airport Security

The following narrative is transcribed from a keynote address presented by Dr. Seth Young, Associate Professor, College of Business Embry-Riddle Aeronautical University, at the ICAO 4th Regional Aviation Security and Facilitation Seminar, held in Amman, Jordan, in September 2002. The seminar was attended by participating member states from ICAO\u27s Middle East region. The purpose of the seminar was to discuss new regulations and policies regarding aviation security, and to become educated in enhancing airport security, from a security, as well as an operations facilitation, perspective

The Geography of Food Cooperatives in the United States

For our society to become sustainably viable in the future, the ways in which we obtain our food and the methods used to create that food will be very important. One of the most environmentally friendly methods of food obtainment is membership in a food cooperative. This research delves into the basics of food cooperatives, highlights similar studies of other sustainability indicators, and examines the geographic distribution of food co-ops across the United States.Faculty Sponsor: Dr. George Pomero

A Disciplined Option Writing Strategy Outperforms a Passive Dow 30 Total Return Index

We have tested a simple option strategy of writing cash collaterized puts and covered calls based on data provided by the IVY Option Metrics Database. This database contains the actual put and call prices from December 31, 1995 to December 31 2010 used in this study. Our base case period for our option strategy (December 31, 1999 to December 31, 2010) has resulted in annualized returns ranging from 5.08% to 5.88% depending upon which P/E multiple cut off we used in our model. Comparatively, the DJIA delivered investors a total return of only 2.41%. Furthermore, our strategy, depending on the P/E cut-off, produced a standard deviation ranging from 4.06% to 5.99% versus the DJIA which had a considerably higher standard deviation of 15.77% for the same period measured. Our results beg the question: on a risk adjusted basis is writing of puts and calls a better strategy than simply investing in a passive index such as the Dow 30 index? The portfolio started with a notional $225,000 investment so as to compare it to a passive index investing strategy. The advantage of a simple, non-levered options writing strategy are significant as it handily outperforms a non-options passive index approach when measured on a risk adjusted basis

Emerging Insights into Antibiotic-Associated Diarrhea and Clostridium difficile Infection through the Lens of Microbial Ecology

Antibiotics are the main, and often only, clinical intervention for prophylactic and active treatment of bacterial infections in humans. Perhaps it is not surprising that these drugs also shift the composition of commensal bacteria inside our bodies, especially those within the gut microbial community (microbiota). How these dynamics ultimately affect the function of the gut microbiota, however, is not fully appreciated. Likewise, how antibiotic induced changes facilitate the outgrowth and pathogenicity of certain bacterial strains remains largely enigmatic. Here, we discuss the merits of a microbial ecology approach toward understanding a common side effect of antibiotic use, antibiotic-associated diarrhea (AAD), and the opportunistic bacterial infections that sometimes underlie it. As an example, we discuss how this approach is being used to address complex disease dynamics during Clostridium difficile infection

Categorizing Flight Paths using Data Visualization and Clustering Methodologies

This work leverages the U.S. Federal Aviation Administration's Traffic Flow Management System dataset and DV8, a recently developed tool for highly interactive visualization of air traffic data, to develop clustering algorithms for categorizing air traffic by their varying flight paths. Two clustering methodologies, a spatial-based geographic distance model, and a vector-based cosine similarity model, are demonstrated and compared for their clustering effectiveness. Examples of their applications reveal successful, realistic clustering based on automated clustering result determination and human-in-the-loop processes, with geographic distance algorithms performing better for enroute portions of flight paths and cosine similarity algorithms performing better for near-terminal operations, such as arrival paths. A point extraction technique is applied to improve computation efficiency.Comment: Published in the 9th International Conference on Research in Air Transportation (ICRAT'20): https://www.icrat.org/previous-conferences/9th-international-conference/papers