Smart Coffee Table

This report documents the process I followed while working on my senior design project. It includes how I decided to build a Smart Coffee Table, my engineering process, the design of all features and mechanical components, relevant research necessary to complete the project, the performance of the structures, the methods for controlling and powering the table, and any problems along the way. Over the course of the last two semesters, I learned valuable lessons pertaining to working on a project from start to finish as an individual rather than in a group

Exploring the role of working memory and understanding educational underachievement in anxiety and depression

Research has shown that high levels of emotion are associated with lowered academic performance. However, the mechanisms involved in this relationship are as yet unclear. One potentially important process is the disruption of working memory. Building on previous research such as Wine (1971) and Sarason (Sarason, 1984), Eysenck and Calvo (1992) formulated a processing efficiency theory (PET) to account for the disruptive effects of anxiety on cognitive task performance. Briefly, PET suggests that anxiety can have the effect of reducing cognitive storage and processing resources in the working memory system. One effect is a reduction in task effectiveness, or the accuracy of performance. H.C. Ellis and colleagues have proposed a similar model, the resource allocation model, with special reference to depressed mood (e.g. Ellis & Moore, 1999). Under both theoretical frameworks, the negative effects of emotion are assumed to be most clearly seen on complex cognitive tasks. In addition, the negative effects of anxiety on performance are thought to be most pronounced under stressful conditions. This thesis explored the relationship between emotion, working memory and academic performance in an attempt to further understand the processes involved in educational underachievement in anxiety and depression. The first empirical investigation reported in Chapter Three was an initial step in testing the simple relationship between three emotions (trait anxiety, depression and test anxiety) and academic performance measures. Consistent with previous research moderate negative relationships were found between the two constructs. Chapter Four showed that working memory partially mediated the negative trait anxiety-academic performance relationship. Chapter Five replicated the mediation hypothesis also incorporating depression and test anxiety. A moderated mediation hypothesis was also tested. That is, that the negative links between emotion, working memory and academic performance were shown to be most pronounced when stress reactivity was high. Chapter Six replicated these moderated mediation results and tested an emotion x working memory interaction hypothesis that suggested that those with high emotion and low working memory were the poorest academic performers. Chapter Seven evaluated the moderated mediation and interaction hypotheses in a longitudinal study which allowed for some preliminary conclusions to be made concerning causality. It was shown that emotion was negatively associated with academic performance via verbal working memory over time when stress reactivity was high. Over time, high emotion and low working memory in combination were associated with lower academic performance. In Chapter Eight, the implications of the findings in this thesis for theory and practice were discussed

Groups and semigroups with a one-counter word problem

We prove that a finitely generated semigroup whose word problem is a one-counter language has a linear growth function. This provides us with a very strong restriction on the structure of such a semigroup, which, in particular, yields an elementary proof of a result of Herbst, that a group with a one-counter word problem is virtually cyclic. We prove also that the word problem of a group is an intersection of finitely many one-counter languages if and only if the group is virtually abelian

Temporal Bandwidth-Intensive Virtual Network Allocation Optimization in Data Centers

Title from PDF of title page, viewed on July 15, 2015Thesis advisor: Deep MedhiVitaIncludes bibliographic references (pages 30-31)Thesis (M.S.)--School of Computing and Engineering. University of Missouri--Kansas City, 2014In this paper, we consider bandwidth-intensive services for customers that want virtual networks (VN) in a data center environment. In particular, we consider this problem in a temporal context where bandwidth-intensive requests from each VN may arrive randomly at a review point, which may last for a certain duration. Thus, at each review point, the data center network provider must optimally allocate resources for the demand requests. For this problem, we present a mixed-integer programming (MIP) problem formulation where any request from a VN customer may be assigned to any virtual machine so that network resource availability is optimized. We present an overbooking strategy that may be employed to allow for some demands not met in the first try. For comparison, we also consider a base case where the allocation is pinned to a specific destination. Through our study, we show the comparative gains of different schemesIntroduction -- Literature survey -- Model -- Results -- Conclusions -- Appendix A. Node numbering -- Appendix B. NetworkSimulation

Quantifying the latitudinal representivity of in situ solar wind observations

Advanced space-weather forecasting relies on the ability to accurately predict near-Earth solar wind conditions. For this purpose, physics-based, global numerical models of the solar wind are initialized with photospheric magnetic field and coronagraph observations, but no further observation constraints are imposed between the upper corona and Earth orbit. Data assimilation (DA) of the available in situ solar wind observations into the models could potentially provide additional constraints, improving solar wind reconstructions, and forecasts. However, in order to effectively combine the model and observations, it is necessary to quantify the error introduced by assuming point measurements are representative of the model state. In particular, the range of heliographic latitudes over which in situ solar wind speed measurements are representative is of primary importance, but particularly difficult to assess from observations alone. In this study we use 40+ years of observation-driven solar wind model results to assess two related properties: the latitudinal representivity error introduced by assuming the solar wind speed measured at a given latitude is the same as that at the heliographic equator, and the range of latitudes over which a solar wind measurement should influence the model state, referred to as the observational localisation. These values are quantified for future use in solar wind DA schemes as a function of solar cycle phase, measurement latitude, and error tolerance. In general, we find that in situ solar wind speed measurements near the ecliptic plane at solar minimum are extremely localised, being similar over only 1° or 2° of latitude. In the uniform polar fast wind above approximately 40° latitude at solar minimum, the latitudinal representivity error drops. At solar maximum, the increased variability of the solar wind speed at high latitudes means that the latitudinal representivity error increases at the poles, though becomes greater in the ecliptic, as long as moderate speed errors can be tolerated. The heliospheric magnetic field and solar wind density and temperature show very similar behaviour

Trumped Up Charges: Empirical Effects of U.S. Immigration Reform on Crime and Jobs

This brief examines the effects, both intended and unintended, of two previous efforts to deter and regulate unauthorized immigration. Recent research shows that the Immigration and Reform Act of 1986, by cutting off access to legal employment for undocumented immigrants, actually increases the probability that some people who are not in the country legally will engage in crime. And despite heightened efforts to police and deport undocumented immigrants in accordance with Section 287(g) of the Immigration and Nationality Act, studies indicate that any resultant decreases in immigrant populations did nothing to improve employment opportunities for low-skilled native residents. While past research reveals some of the limitations and unintended negative impacts of laws aimed at making the U.S. less attractive to unauthorized immigrants, less is known about the potential positive impacts of laws aimed at inclusion. Such knowledge could help to enlighten future debates over comprehensive reform.https://repository.upenn.edu/pennwhartonppi/1029/thumbnail.jp

Help-seeking in emerging adults with and without a history of mental health referral: a qualitative study.

BACKGROUND: Young people are generally reluctant to seek professional help when experiencing problems. However, past experience of services is often cited as increasing the intention to seek help, therefore those with a history of mental health referral may adopt more adaptive help seeking strategies. The current study investigated whether the pattern of different help seeking strategies and barriers to help seeking differed as a function of previous referral history. METHODS: Semi-structured interviews were conducted with 29 emerging adults (12 males, 17 females); 17 with a history of mental health referral and 12 without and analysed using thematic analysis. RESULTS: Overall, those with a referral to services were more likely than those without to rely on avoidant coping, especially techniques that depended upon suppression. This could help account for the increased use of strategies involving self-harm and substances in those with past referral. An exploration of barriers to help seeking showed those with a history of mental health referral were much more likely to self-stigmatise and this became attached to their sense of identity. CONCLUSIONS: Emerging adults with a history of referral are more likely to adopt avoidant coping strategies when dealing with problems and self-stigmatise to a greater degree than those without a history of referral. This suggests that current approaches to mental health in emerging adults are not decreasing the sense of stigma with potentially far-reaching consequences for the developing sense of self and choice of help seeking strategies.This work was supported by the Wellcome Trust programme Grant (No. 053642). Ruth Spence was funded by a doctoral studentship through CLAHRC.This is the final version of the article. It first appeared from BioMed Central at http://dx.doi.org/10.1186/s13104-016-2227-8

The evolution of inverted magnetic fields through the inner heliosphere

Local inversions are often observed in the heliospheric magnetic field (HMF), but their origins and evolution are not yet fully understood.Parker Solar Probe has recently observed rapid, Alfvénic, HMF inversions in the inner heliosphere, known as ‘switchbacks’, which have been interpreted as the possible remnants of coronal jets. It has also been suggested that inverted HMF may be produced by near-Sun interchange reconnection; a key process in mechanisms proposed for slow solar wind release. These cases suggest that the source of inverted HMF is near the Sun, and it follows that these inversions would gradually decay and straighten as they propagate out through the heliosphere. Alternatively, HMF inversions could form during solar wind transit, through phenomena such velocity shears, draping over ejecta, or waves and turbulence. Such processes are expected to lead to a qualitatively radial evolution of inverted HMF structures. Using Helios measurements spanning 0.3–1 AU, we examine the occurrence rate of inverted HMF, as well as other magnetic field morphologies, as a function of radial distance r, and find that it continually increases. This trend may be explained by inverted HMF observed between 0.3–1 AU being primarily driven by one or more of the above in-transit processes, rather than created at the Sun. We make suggestions as to the relative importance of these different processes based on the evolution of the magnetic field properties associated with inverted HMF. We also explore alternative explanations outside of our suggested driving processes which may lead to the observed trend

Glutamine supports the protection of tissue cells against the damage caused by cholesterol-dependent cytolysins from pathogenic bacteria

Pathogenic bacteria often damage tissues by secreting toxins that form pores in cell membranes, and the most common pore-forming toxins are cholesterol-dependent cytolysins. During bacterial infections, glutamine becomes a conditionally essential amino acid, and glutamine is an important nutrient for immune cells. However, the role of glutamine in protecting tissue cells against pore-forming toxins is unclear. Here we tested the hypothesis that glutamine supports the protection of tissue cells against the damage caused by cholesterol-dependent cytolysins. Stromal and epithelial cells were sensitive to damage by the cholesterol-dependent cytolysins, pyolysin and streptolysin O, as determined by leakage of potassium and lactate dehydrogenase from cells, and reduced cell viability. However, glutamine deprivation increased the leakage of lactate dehydrogenase and reduced the viability of cells challenged with cholesterol-dependent cytolysins. Without glutamine, stromal cells challenged with pyolysin leaked lactate dehydrogenase (control vs. pyolysin, 2.6 ± 0.6 vs. 34.4 ± 4.5 AU, n = 12), which was more than three-fold the leakage from cells supplied with 2 mM glutamine (control vs. pyolysin, 2.2 ± 0.3 vs. 9.4 ± 1.0 AU). Glutamine cytoprotection did not depend on glutaminolysis, replenishing the Krebs cycle via succinate, changes in cellular cholesterol, or regulators of cell metabolism (AMPK and mTOR). In conclusion, although the mechanism remains elusive, we found that glutamine supports the protection of tissue cells against the damage caused by cholesterol-dependent cytolysins from pathogenic bacteria