Evaluating barriers to and impacts of rural broadband access

The lack of adequate broadband infrastructure persists in many rural communities. Beyond funding, additional barriers persist, such as digital literacy and community-level self-efficacy. As a result, the first contribution articulates barriers at the organizational level. This work proposes a framework based on the Theory of Planned Behavior to highlight stakeholder dynamics that have constrained Regional Planning Commissions from advancing broadband infrastructure in rural areas. One approach to address these barriers is to provide stakeholders with analytical tools to evaluate the benefits and costs of various broadband options for their community since there is not a one-size-fits-all solution. To this end, there are three contributions that provide guidance for evaluating improved broadband access. The first solution proposes a benefit-cost analysis at the county-level where changes in tax revenue are used to monetize the impact of rural broadband for a hypothetical Midwest county. The second solution demonstrates a method for evaluating the benefit of broadband in terms of social impact on education, employment, and healthcare in a small under-served community in northwest Missouri. Pre- and post-survey data were used to conduct comparisons between the targeted community, which received faster internet, and control communities. The third solution describes a socio-technical reference architecture to support the development of community-driven wireless broadband projects. By providing analytical tools for evaluating the impact of broadband solutions for rural communities, this research increases the capability of local communities to identify and advocate for broadband solutions that fit their needs --Abstract, page iv

Proceedings, MSVSCC 2018

Proceedings of the 12th Annual Modeling, Simulation & Visualization Student Capstone Conference held on April 19, 2018 at VMASC in Suffolk, Virginia. 155 pp

Process monitoring for material extrusion additive manufacturing: a state-of-the-art review

Qualitative uncertainties are a key challenge for the further industrialization of additive manufacturing. To solve this challenge, methods for measuring the process states and properties of parts during additive manufacturing are essential. The subject of this review is in-situ process monitoring for material extrusion additive manufacturing. The objectives are, first, to quantify the research activity on this topic, second, to analyze the utilized technologies, and finally, to identify research gaps. Various databases were systematically searched for relevant publications and a total of 221 publications were analyzed in detail. The study demonstrated that the research activity in this field has been gaining importance. Numerous sensor technologies and analysis algorithms have been identified. Nonetheless, research gaps exist in topics such as optimized monitoring systems for industrial material extrusion facilities, inspection capabilities for additional quality characteristics, and standardization aspects. This literature review is the first to address process monitoring for material extrusion using a systematic and comprehensive approach

Hierarchical categorisation of tags for delicious

In the scenario of social bookmarking, a user browsing the Web bookmarks web pages and assigns free-text labels (i.e., tags) to them according to their personal preferences. In this technical report, we approach one of the practical aspects when it comes to represent users' interests from their tagging activity, namely the categorization of tags into high-level categories of interest. The reason is that the representation of user profiles on the basis of the myriad of tags available on the Web is certainly unfeasible from various practical perspectives; mainly concerning the unavailability of data to reliably, accurately measure interests across such fine-grained categorisation, and, should the data be available, its overwhelming computational intractability. Motivated by this, our study presents the results of a categorization process whereby a collection of tags posted at Delicious #http://delicious.com# are classified into 200 subcategories of interest.Preprin

Hierarchical categorisation of web tags for Delicious

In the scenario of social bookmarking, a user browsing the Web bookmarks web pages and assigns free-text labels (i.e., tags) to them according to their personal preferences. The benefits of social tagging are clear – tags enhance Web content browsing and search. However, since these tags may be publicly available to any Internet user, a privacy attacker may collect this information and extract an accurate snapshot of users’ interests or user profiles, containing sensitive information, such as health-related information, political preferences, salary or religion. In order to hinder attackers in their efforts to profile users, this report focuses on the practical aspects of capturing user interests from their tagging activity. More accurately, we study how to categorise a collection of tags posted by users in one of the most popular bookmarking services, Delicious (http://delicious.com).Preprin

Relevant Environments for Analysis and Development (READy): Enabling Human Space Exploration Through Integrated Operational Testing

No abstract availabl

Molecular dynamics simulations of small molecule diffusion in hydrogels

Solute diffusion across polymer matrices is important in several technological applications such as controlled drug delivery, gel electrophoresis and gas separation. Our primary objective is to investigate the effect of size-exclusion on solute diffusion in polymer matrices with a focus on crosslinked hydrogel networks. The diffusion co-efficient of a solute in a hydrogel depends on the free-volume available as determined by the solute size and the polymer concentration. However, hydrogels have a highly disordered pore structure due to the random nature of the crosslinking techniques used in their preparation. The characterization of the free-volume of this pore structure by experimental techniques or mathematical modeling is not straightforward. Consequently, this precludes a direct testing of the correlation between diffusion and free-volume. In this thesis, we prepare simple, defect-free, end-crosslinked polymer networks via computer simulation. We choose a coarse-grained bead-spring representation for our polymer chains. In addition to crosslinked networks, we also prepare other host matrices: polymer solutions composed of flexible chains and fibrous matrices composed of interpenetrating rods. The free-volume available to a solute of a given size in these host matrices is characterized by calculating the so-called accessible volume fraction. Subsequently, the solute diffusion coefficients are computed by performing Molecular Dynamics (MD) simulations. Our general finding is that the solute diffusion coefficients in these host matrices correlate well with the accessible volume fraction, which collapses onto one single variable the twin effects of solute size and polymer concentration. In the case of a crosslinked network with a given crosslinking density, solute diffusivities are a unique function of the accessible volume fraction. We also conclude that the mobility of the chains in the polymer matrix has a significant effect on solute diffusion, even at high accessible volume fraction. We have also investigated the effect of attractive solute-polymer interactions on solute partitioning and diffusion in crosslinked networks. A solute with specific interactions diffuses faster than an inert solute of the same size. We attribute this to the active partitioning of solutes across the bottlenecks in the network that the solute encounters during diffusion.Ph.D., Chemical Engineering -- Drexel University, 200

Integrating the Arts and Sciences in the Museum Setting

The division between the arts and sciences appears to be deepening in America. As political leaders emphasize STEM (science, technology, engineering and math) education in schools, arts education is diminished to make room for STEM courses. Concerned about this phenomenon, many art educators are working to integrate the arts into STEM education through a variety of arts integration efforts. Arts integration not only helps to preserve a place for the arts in the curriculum, it also has been shown to enhance STEM learning. Arts integration is of special interest to art museum educators who feel that they can provide resources to help teachers integrate the arts into STEM. By offering arts integration curricula, a museum supports its community and maintains its own relevance. Also, while general museum funding is decreasing, grant money is being made available to museums to support the areas of STEM and arts integration. Schools are also more inclined to visit museums when the museum can provide arts integration that ties to STEM learning. This paper explores five efforts by museums to support their communities and retain their relevance through arts integration programs. The case studies include the J. Paul Getty Museum in Los Angeles, California; The National Museum of Math in Manhattan, New York; The Walters Art Museum in Baltimore Maryland; The Kennedy Center ArtsEdge in Washington D.C., and the Museum of Glass in Tacoma, Washington. These case studies review the development of the arts integration programs at each museum, describe the programming and review lessons plans, and demonstrate how they benefit students and teachers. Evaluations and critiques of each program are included

Integrating the Arts and Sciences in the Museum Setting

The division between the arts and sciences appears to be deepening in America. As political leaders emphasize STEM (science, technology, engineering and math) education in schools, arts education is diminished to make room for STEM courses. Concerned about this phenomenon, many art educators are working to integrate the arts into STEM education through a variety of arts integration efforts. Arts integration not only helps to preserve a place for the arts in the curriculum, it also has been shown to enhance STEM learning. Arts integration is of special interest to art museum educators who feel that they can provide resources to help teachers integrate the arts into STEM. By offering arts integration curricula, a museum supports its community and maintains its own relevance. Also, while general museum funding is decreasing, grant money is being made available to museums to support the areas of STEM and arts integration. Schools are also more inclined to visit museums when the museum can provide arts integration that ties to STEM learning. This paper explores five efforts by museums to support their communities and retain their relevance through arts integration programs. The case studies include the J. Paul Getty Museum in Los Angeles, California; The National Museum of Math in Manhattan, New York; The Walters Art Museum in Baltimore Maryland; The Kennedy Center ArtsEdge in Washington D.C., and the Museum of Glass in Tacoma, Washington. These case studies review the development of the arts integration programs at each museum, describe the programming and review lessons plans, and demonstrate how they benefit students and teachers. Evaluations and critiques of each program are included

Adaptive laboratory evolution of microbial co-cultures for improved metabolite secretion.

Adaptive laboratory evolution has proven highly effective for obtaining microorganisms with enhanced capabilities. Yet, this method is inherently restricted to the traits that are positively linked to cell fitness, such as nutrient utilization. Here, we introduce coevolution of obligatory mutualistic communities for improving secretion of fitness-costly metabolites through natural selection. In this strategy, metabolic cross-feeding connects secretion of the target metabolite, despite its cost to the secretor, to the survival and proliferation of the entire community. We thus co-evolved wild-type lactic acid bacteria and engineered auxotrophic Saccharomyces cerevisiae in a synthetic growth medium leading to bacterial isolates with enhanced secretion of two B-group vitamins, viz., riboflavin and folate. The increased production was specific to the targeted vitamin, and evident also in milk, a more complex nutrient environment that naturally contains vitamins. Genomic, proteomic and metabolomic analyses of the evolved lactic acid bacteria, in combination with flux balance analysis, showed altered metabolic regulation towards increased supply of the vitamin precursors. Together, our findings demonstrate how microbial metabolism adapts to mutualistic lifestyle through enhanced metabolite exchange