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On Reconstructing Gaussian Mixtures from the Distance Between Two Samples: An Algebraic Perspective
No full textThis thesis is concerned with the problem of characterizing the orbits of certain probability density functions under the action of the Euclidean group. Our motivating application is the recognition of a point configuration where the coordinates of the points are measured under noisy conditions. Consider a random variable X in R¢ with probability density function p(.e). Let x and rz be independent random samples following p(x). Define A as the squared Euelidean distance between x; and zz. It has previously been shown that two distributions p(x) and p(x) consisting of Dirac delta distributions in generic positions that have the same respective distributions of A are necessarily related by a rigid motion. That is, there exists some rigid motion g in the Euclidean group p(x) such that p(x) = P(g - x) for all x € Rd. To account for noise in the measurements. we assume X is a random variable in R¢ whose density is a k-component mixture of Gaussian distributions with means in generic position. We further assume that the covariance matrices of the Gaussian components are equal and of the form © = 971, with o? € Roo.In Theorem 3.1.1 and Theorem 3.2.1, we prove that, when o? is known, generic k- component Gaussian mixtures are uniquely reconstructible up to a rigid motion from the density of ∆. A more general formulation is proven in Theorem 3.2.3. Similarly, when is unknown, we prove in Theorem 4.1.1 and Theorem 4.1.2 that generic equally-weighted k-component Gaussian mixtures with & = 1 and k = 2 are uniquely reconstructible up to a rigid motion from the distribution of ∆. There are at most three non-equivalent equally- weighted 3-component Gaussian mixtures up to a rigid motion having the same distribution of A, as proven in Theorem 4.1.3. In Theorem 1.1.4, we present. a test to check if, for a given & and d, the number of non-equivalent equally-weighted k-component Gaussian mixtures in R¢ having the same distribution of ∆ is at most (3) +1. Numerical computations showed that distributions with k = 4,5.6,7 such that d \u3c k—2 and (k,d) = (8,1) pass the test, and thus have a finite number of reconstructions up to a rigid motion. When a2 is unknown and the mixture weights are also unknown, we prove in Theorem 1.2.) that there are at most four non-equivalent 2-component Gaussian mixtures up to a rigid motion having the same distribution of ∆
Using Behavior Sequence Analysis to Study Teams During Long- Duration Isolation and Confinement
Get PDFWith a renewed impetus and appetite for human space exploration, both government-funded agencies and private companies are focusing on longer and farther crewed missions into the solar system. Such space missions rely on highly interdependent teams living and working together in isolated, confined, and extreme (ICE) environments. Understanding the behavioral patterns of teams in ICE environments is, thus, paramount for the future success of such missions. Due to the complexity of studying ICE teams, several researchers have called for methodological innovations to advance knowledge in this area. In the current research, a proof-of-concept methodological approach is introduced that provides a potential solution for several shortcomings of traditional approaches. A behavior sequence analysis (BSA) approach was used to analyze two historical polar expedition journals, resulting in data depicting transitions from antecedent behaviors or emotions into sequitur behaviors/emotions amongst the expeditions’ teams. The data are described, illustrated by corresponding state transition diagrams, and possible ways of interpreting the data are introduced. Applications and limitations of the used approach as well as possible future developmental steps for the method are discussed. In general, BSA was demonstrated as a potentially useful methodology for extracting meaningful data from long texts, showing detailed connections between a myriad of events, behaviors, and emotional responses of individuals and wider teams
Indirect Detection Search for Dark Matter
No full textPresent WIMP Dark Matter search strategies are mainly focused on possible direct detection through elastic or inelastic scatterings on atomic nuclei, or with electrons. This approach becomes insensitive to MDM \u3c 10 GeV. Indirect DM detection refers to the search for DMDM or DM-M annihilation, decay debris from DM particles, or other particle production, resulting in detectable species.New physics processes, initiated by cosmic ray or dark matter interactions may be observable in underground indirect search experiments by excess high multiplicity neutron production in nuclear targets. Even for MDM \u3c 10 GeV, DM-M interaction is capable of producing large signals, \u3e200 neutrons if the energy is deposited in a Pb target.The NMDS-II detector, located at an underground laboratory within the Pyhasälmi complex metal mine in central Finland, collated data for 6504 ± 1 hours at 583 m.w.e. and for 1440 ± 1 hours at 1166 m.w.e.. The detector system consists of a 30 cm cube Pb-target surrounded by 60 3He proportional tubes and a two layer Geiger Counter muon detection system. The lead target is used to interact with potential dark matter particles, and neutron numbers are measured with 3He tubes. The neutron event multiplicity production is compared to Geant4 simulations, starting with the well measured absolute muon momentum and angular distribution flux rate at sea level, then propagating the muon flux through rock while preserving the momentum-angular correlation to a depth 4m above the the detector at the two depth locations. The muon flux modeling is compared to the uncorrelated Miyake model at each depth as verification of the muon propagation simulation. Finally, the Geant4 fully simulates the passage of the muon and its induced showers through a model universe 10000 m2 x 12 m depth, and the simulated response of the detector to the calculated muon flux, is compared with the data.The Geant4 prediction and the observed data neutron event multiplicity distributions have matching power law shapes, k × n −p , and do not have exponential shapes. For the data collected at 583 m.w.e., p=2.36±0.10 with χ 2/DoF = 0.76 and for the simulation p=2.34±0.01 with χ 2/DoF = 1.05. At 1166 m.w.e., p=2.29±0.007 for the simulation with χ 2/DoF = 1.16. And for the data the collection with only 6 detected events above multiplicity 5, yields p=2.50 ± 0.35 predicted by the Maximum Likelihood Estimatation method.The DM acceptance as a function of mass is found using a proton-Pb spallation model. The dark matter mass is assumed to be equal to the proton kinetic energy and to interact uniformly over the volume of the lead target. The number of excess events is found to be −6.1 ± 5.1, that is no excess events are observed. The upper limit with 90% confidence level is then found assuming 2.3 events. The Poisson estimation then yielding search limits 1.1×10−44 cm−2 for 10 GeV deposited energy, 1.9×10−45 cm−2 at 1 GeV and 3.0×10−45 cm−2 for 500 MeV deposited energy and no acceptance at 100 MeV.An indirect dark matter search was conducted based on DM-M interactions depositing energy in a Pb-target allowing DM masses to be probed in a region 100 MeV \u3c MDM \u3c 10 GeV not accessible to direct dark matter searches. Limits are placed on DM-M energy deposition independent of the DM-M interaction
Joint Learning And Optimization Methodologies for Advancing Next Generation Communication Systems
No full textIn order to advance next-generation communication systems, it is critical to enhance the state-of-the-art communication architectures, such as device-to-device (D2D), multipleinput multiple-output (MIMO), and intelligent reflecting surface (IRS), in terms of achieving high data rate, low latency, and high energy efficiency. In the first part of this dissertation, we address joint learning and optimization methodologies on cutting-edge network architectures. First, we consider D2D networks equipped with MIMO systems. In particular, we address the problem of minimizing the network overhead in D2D networks, defined as the sum of time and energy required for processing tasks at devices, through the design for MIMO beamforming and communication/computation resource allocation. Second, we address IRS-assisted communication systems. Specifically, we study an adaptive IRS control scheme considering realistic IRS reflection behavior and channel environments, and propose a novel adaptive codebook-based limited feedback protocol and learning-based solutions for codebook updates.Furthermore, in order for revolutionary innovations to emerge for future generations of communications, it is crucial to explore and address fundamental, long-standing open problems for communications, such as the design of practical codes for a variety of important channel models. In the later part of this dissertation, we study the design of practical codes for feedback-enabled communication channels, i.e., feedback codes. The existing feedback codes, which have been developed over the past six decades, have been demonstrated to be vulnerable to high forward/feedback noises, due to the non-triviality of the design of feedback codes. We propose a novel recurrent neural network (RNN) autoencoder-based architecture to mitigate the susceptibility to high channel noises by incorporating domain knowledge into the design of the deep learning architecture. Using this architecture, we suggest a new class of non-linear feedback codes that increase robustness to forward/feedback noise in additive White Gaussian noise (AWGN) channels with feedback
Our Primate Materials Robert M. Yerkes and the Introduction of the Primate to Problems of Human Betterment in the American Eugenics Movement
No full textMy master\u27s thesis examines how eugenicist and psychologist Robert M. Yerkes’ experimental intelligence research helped to situate the non-human primate as the ideal research subject for human betterment research in the twentieth century U.S. Yerkes believed that the primate was the ideal research subject to address questions of human betterment and social welfare, specifically best to create methods of evaluating the imagined threat of intellectual disability. While Yerkes has been studied extensively in the history of psychology, primatology, and eugenics, rarely have his separate contributions to these fields been placed in conversation with one another. Placing the primate at the center of Yerkes’ work allows for all three fields to engage with one another in a new perspective. By analyzing Yerkes’ publications about the Multiple-Choice Experiment within the context of the American eugenics’ movement, we can see how the primate came to hold a central position in U.S. scientific research, the advancement of human welfare and betterment, and as a means of defining what it means to be human. This story offers a glimpse into this longer process of how the primate came to occupy this position, but even a glimpse offers historians of the American eugenics’ movement new questions. What was the role of the non-human animal in the formulation of American eugenic theories? How have we historically used the natural world in our attempts to separate ourselves from it? And can we truly reconcile a history with eugenics if we continue to ignore the role of animals within it, they who today exist unquestionably within the status of the sub-human
ZDR ARC Area And Intensity as a Precursor to Low Level Rotation in Supercells
No full textIt has been hypothesized that some measurable properties of ZDR arcs in supercells may change in the minutes prior to tornadogenesis and tornadogenesis failure, and that ZDR arc area will change with SRH and can be used as a real-time proxy to estimate SRH. Output form the Cloud Model 1 (CM1) along with a polarimetric emulator is used to simulate ZDR arcs in 9 tornadic and 9 non-tornadic supercells. A random forest algorithm is used to automatically identify the ZDR arcs. Finally the inflow sector SRH is calculated at times when ZDR arcs are identified. To analyze the change in intensity and area a comparison between the average ZDR value inside and outside of the arc, as well as the spatial size of the arc and storm was done. Model calculated SRH is then compared to these metrics.It has also been observed that hail fallout complicates the automatic identification of ZDR arcs. In this study, three experiments are run where the simulated ZDR arcs are produced. One using all categories of hydrometeors, one where wet growth and melting of hail is excluded, and one excluding the contribution to ZDR from the hail hydrometeor category. The same analysis as above is repeated for all three experiments. Finally observed ZDR arcs are analyzed to see if these results are applicable to the real world
Second Language Discourse Markers and Study Abroad: the Case of Pues and Bueno in Peninsular Spanish
No full textThis investigation examined the effectiveness of different types of explicit classroom instruction on second language (L2) development of the Spanish discourse marker (DM) pues. While several studies have addressed the positive effect of explicit instruction on L2 DM development, the current investigation moves beyond the explicit-implicit method debate by examining the comparative effectiveness of different types of explicit instruction, specifically by comparing the effects of concept-based instruction (CBI), rule-based instruction (RBI), and a control group (CTRL). This investigation contributes to the field of instructed pragmatics by demonstrating how different types of explicit instruction can affect the robustness of pragmatics learning outcomes. Furthermore, with the inclusion of CBI, this investigation expands theoretical paradigms for L2 pragmatics teaching to include a less explored framework for instruction — sociocultural theory (Vygotsky, 1987).Given the learnability problem posed by the low perceptual salience and extensive multifunctionality of DMs, along with their conceptual connections to important interactional practices and to a semantic core that guides their use in discourse, DMs and pues specifically were identified as a potentially ideal candidate for development through CBI. Pues is translated in English to ‘so’, ‘then’, ‘cos’, and ‘well’ and is a highly frequent feature of Spanish conversation (Domínguez García, 2016; Stenström, 2006a; Stenström, 2006b). DMs like pues contribute to speakers’ ability to communicate effectively and participate in social interaction (Crible & Pascual, 2020; Hayano, 2011; Hoshi, 2017; Thörle, 2016) and, thus, they are important linguistic features for L2 speakers.Using a pre, post, and delayed post design, data were collected using an oral decisionmaking task and a dialogue reflection task. The analyses addressed whether CBI, RBI, and CTRL produce the same effect on L2 Spanish learners’ pues frequency of use, pues functional range, and use of pues in interaction. As a secondary objective, the analyses also considered whether CBI and RBI produce the same effect on L2 Spanish learners’ ability to transfer learning to unlearned DMs.Quantitative analyses, which addressed the learners’ ability to use pues frequently and for a range of functions, indicated an advantage for the CBI group, with CBI learners using pues with greater frequency of use and functional range than RBI and CTRL learners. The qualitative analysis, which addressed the learners’ ability to use pues in interaction, also indicated an advantage for the CBI group, with CBI learners using pues to express a stance of givenness towards utterances as well as to manage turn-taking in interaction. CBI learners’ use of pues for accomplishing these two interactional practices indicated a deeper understanding of pues and how the DM can be used to accomplish social actions in interaction. Overall, the findings provide support for the claim that CBI is superior to traditional explicit models of instruction (Erikson, Lanning, & French, 2017) and suggest that the learnability problem of DMs may be lessened by providing a conceptual structure that presents learners with a framework for organizing DM multifunctionality and that also highlights the interactional importance of DMs as tools that can be used to accomplish social actions. The findings are discussed considering the role of conceptual knowledge in L2 DM development and implications for pragmatics instruction
The Effects of Ultra-Marathon Trail Running and the Physiological Response of Stress on Salivary Biomarkers
Get PDFPURPOSE: This study investigated changes in salivary α-amylase (sAA), cortisol, and interleukin-1β (IL-1β) concentrations following completion of an ultra-marathon trail run (UMT) to better understand the physiological stressors imposed by this extreme type of race. METHODS: Eight subjects participated in this study. Each subject completed a 50 km UMT. Two-minute oral salivary swabs were taken 10 minutes prior to race start and again within 1 minute of race finish. Samples were analyzed for sAA, cortisol and IL-1β using ELISA kits. RESULTS: Our results demonstrated a significant increase in both sAA (p = 0.002) and cortisol (p \u3c 0.001) from baseline. No significant differences were observed for IL-1β. There was no significant relationship between the observed sAA increase and race speed. The observed increase in cortisol was significantly correlated with race speed (R2 = 0.582, p = 0.028). CONCLUSION: Participation in UMT is associated with activation of the sympathoadrenal and hypothalamic–pituitary–adrenal axes, but not an increase in IL-1β. Better understanding of physiological stress associated with ultra-distance events could lead to improvements in training and performance for individuals engaging in long-distance aerobic events
The role of academic libraries and the need for librarians\u27 competences to facilitate citizen science
Get PDFAcademic libraries in Estonia, Latvia and Lithuania, together with partners from Greece and Germany, are implementing the LibOCS project University libraries strengthening the academia-society connection through citizen science in the Baltics which aims to: - Identify the drivers and barriers for researchers, members of the public and librarians to engage in citizen science projects; - define the role of academic libraries as facilitators between researchers and members of the public in promoting citizen science activities in the Baltic region; - Identify relevant competences of librarians implementing citizen science projects; - develop openly accessible training modules for librarians to help them acquire competences for engagement in citizen science. This poster presents the objectives and results of the project
Creating Informed Learners in the Classroom Facilitator Handbook
Get PDFhttps://docs.lib.purdue.edu/cilcbk/1000/thumbnail.jp