5,151 research outputs found

    Meso-scale FDM material layout design strategies under manufacturability constraints and fracture conditions

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    In the manufacturability-driven design (MDD) perspective, manufacturability of the product or system is the most important of the design requirements. In addition to being able to ensure that complex designs (e.g., topology optimization) are manufacturable with a given process or process family, MDD also helps mechanical designers to take advantage of unique process-material effects generated during manufacturing. One of the most recognizable examples of this comes from the scanning-type family of additive manufacturing (AM) processes; the most notable and familiar member of this family is the fused deposition modeling (FDM) or fused filament fabrication (FFF) process. This process works by selectively depositing uniform, approximately isotropic beads or elements of molten thermoplastic material (typically structural engineering plastics) in a series of pre-specified traces to build each layer of the part. There are many interesting 2-D and 3-D mechanical design problems that can be explored by designing the layout of these elements. The resulting structured, hierarchical material (which is both manufacturable and customized layer-by-layer within the limits of the process and material) can be defined as a manufacturing process-driven structured material (MPDSM). This dissertation explores several practical methods for designing these element layouts for 2-D and 3-D meso-scale mechanical problems, focusing ultimately on design-for-fracture. Three different fracture conditions are explored: (1) cases where a crack must be prevented or stopped, (2) cases where the crack must be encouraged or accelerated, and (3) cases where cracks must grow in a simple pre-determined pattern. Several new design tools, including a mapping method for the FDM manufacturability constraints, three major literature reviews, the collection, organization, and analysis of several large (qualitative and quantitative) multi-scale datasets on the fracture behavior of FDM-processed materials, some new experimental equipment, and the refinement of a fast and simple g-code generator based on commercially-available software, were developed and refined to support the design of MPDSMs under fracture conditions. The refined design method and rules were experimentally validated using a series of case studies (involving both design and physical testing of the designs) at the end of the dissertation. Finally, a simple design guide for practicing engineers who are not experts in advanced solid mechanics nor process-tailored materials was developed from the results of this project.U of I OnlyAuthor's request

    A Decision Support System for Economic Viability and Environmental Impact Assessment of Vertical Farms

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    Vertical farming (VF) is the practice of growing crops or animals using the vertical dimension via multi-tier racks or vertically inclined surfaces. In this thesis, I focus on the emerging industry of plant-specific VF. Vertical plant farming (VPF) is a promising and relatively novel practice that can be conducted in buildings with environmental control and artificial lighting. However, the nascent sector has experienced challenges in economic viability, standardisation, and environmental sustainability. Practitioners and academics call for a comprehensive financial analysis of VPF, but efforts are stifled by a lack of valid and available data. A review of economic estimation and horticultural software identifies a need for a decision support system (DSS) that facilitates risk-empowered business planning for vertical farmers. This thesis proposes an open-source DSS framework to evaluate business sustainability through financial risk and environmental impact assessments. Data from the literature, alongside lessons learned from industry practitioners, would be centralised in the proposed DSS using imprecise data techniques. These techniques have been applied in engineering but are seldom used in financial forecasting. This could benefit complex sectors which only have scarce data to predict business viability. To begin the execution of the DSS framework, VPF practitioners were interviewed using a mixed-methods approach. Learnings from over 19 shuttered and operational VPF projects provide insights into the barriers inhibiting scalability and identifying risks to form a risk taxonomy. Labour was the most commonly reported top challenge. Therefore, research was conducted to explore lean principles to improve productivity. A probabilistic model representing a spectrum of variables and their associated uncertainty was built according to the DSS framework to evaluate the financial risk for VF projects. This enabled flexible computation without precise production or financial data to improve economic estimation accuracy. The model assessed two VPF cases (one in the UK and another in Japan), demonstrating the first risk and uncertainty quantification of VPF business models in the literature. The results highlighted measures to improve economic viability and the viability of the UK and Japan case. The environmental impact assessment model was developed, allowing VPF operators to evaluate their carbon footprint compared to traditional agriculture using life-cycle assessment. I explore strategies for net-zero carbon production through sensitivity analysis. Renewable energies, especially solar, geothermal, and tidal power, show promise for reducing the carbon emissions of indoor VPF. Results show that renewably-powered VPF can reduce carbon emissions compared to field-based agriculture when considering the land-use change. The drivers for DSS adoption have been researched, showing a pathway of compliance and design thinking to overcome the ‘problem of implementation’ and enable commercialisation. Further work is suggested to standardise VF equipment, collect benchmarking data, and characterise risks. This work will reduce risk and uncertainty and accelerate the sector’s emergence

    Strategies for Early Learners

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    Welcome to learning about how to effectively plan curriculum for young children. This textbook will address: • Developing curriculum through the planning cycle • Theories that inform what we know about how children learn and the best ways for teachers to support learning • The three components of developmentally appropriate practice • Importance and value of play and intentional teaching • Different models of curriculum • Process of lesson planning (documenting planned experiences for children) • Physical, temporal, and social environments that set the stage for children’s learning • Appropriate guidance techniques to support children’s behaviors as the self-regulation abilities mature. • Planning for preschool-aged children in specific domains including o Physical development o Language and literacy o Math o Science o Creative (the visual and performing arts) o Diversity (social science and history) o Health and safety • Making children’s learning visible through documentation and assessmenthttps://scholar.utc.edu/open-textbooks/1001/thumbnail.jp

    Leading a movement towards effective valuation processes and equal value distributions : the role of specialty coffee

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    The coffee industry is at risk as the disparity of wealth between coffee-producing and coffee-consuming countries increases and enormous obstacles such as environmental crises and extreme price volatility are blocking the path to a sustainable and viable coffee industry. Specialty Coffee is defined as the highest quality coffee premium and has proven to be the front-runner in the transition towards a more sustainable coffee industry. Therefore, this study contributed to previous research by adopting an unique in-depth case study of the Specialty Coffee value chain approach and by isolating this segment and understanding the dynamics between different actors and stakeholders. Moreover, this study will supplement previous research by taking a holistic perspective on valuation processes by including both intrinsic and extrinsic production systems and analyzing different actors' perspectives instead of focusing on a specific actor or step within the value chain. Valuation Theory will provide the theoretical framework to answer the research question: How can actors of the Specialty Coffee industry construct valuation processes for a more equal distribution of value? This study found that actors of the specialty coffee industry are setting the stage for systemic stage through Collective Action. The Collective Action of the industry is directed at building Value Networks with coffee-producing actors at the center, which should guarantee a more equal distribution of wealth and power. Moreover, the Collective Action aims to improve the degree of transparency and measurability of processes that consequently enhances the effectiveness of valuation processes.A indústria do café está em risco porque a desingualdade de riqueza entre os países productores e os países consumidores está aumentendo e alem disto há obstáculos enormes como os crises ambientais e a instabilidade dos preços que estão a bloquear o caminho para uma indústria de café sustentável. O café especial é definido como o café premuim de qualidade mais elevada é tem provado ser o líder na transição para uma nova indústria de café. Além disso, irá complementar a investigação anterior, adotando uma perspetiva holística dos processos de avaliação no que diz respeito a cafés especiais, incluindo sistemas de produção intrínsecos e extrínsecos e analisando as perspetivas dos diferentes intervenientes em vez de se concentrar num só interveniente ou numa só etapa específica dentro da cadeia de valor. A Teoria da Valorização fornecerá o quadro teórico para responder à questão da investigação: Como é que estão os intervenientes da indústria de cafés especiais a construir processos de avaliação para uma distribuição mais equitativa do valor? Este estudo acha que intervenientes da indústria de café especial criam o cenário para um cenário sitémico pela Ação Coletiva. A Ação Coletiva da indústria dirige-se á construção dos Redes de Valor em que os intervenientes que produzem café encontram-se no centro, o que deve guarantizar uma distribuição mais justa de riqueza e poder. Além disso, a Ação Coletiva visa a melhorar o nível de transparência e de mensurabilidade dos processos que por conseguinte aumenta a eficácia dos processos de avaliação

    Z-Numbers-Based Approach to Hotel Service Quality Assessment

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    In this study, we are analyzing the possibility of using Z-numbers for measuring the service quality and decision-making for quality improvement in the hotel industry. Techniques used for these purposes are based on consumer evalu- ations - expectations and perceptions. As a rule, these evaluations are expressed in crisp numbers (Likert scale) or fuzzy estimates. However, descriptions of the respondent opinions based on crisp or fuzzy numbers formalism not in all cases are relevant. The existing methods do not take into account the degree of con- fidence of respondents in their assessments. A fuzzy approach better describes the uncertainties associated with human perceptions and expectations. Linguis- tic values are more acceptable than crisp numbers. To consider the subjective natures of both service quality estimates and confidence degree in them, the two- component Z-numbers Z = (A, B) were used. Z-numbers express more adequately the opinion of consumers. The proposed and computationally efficient approach (Z-SERVQUAL, Z-IPA) allows to determine the quality of services and iden- tify the factors that required improvement and the areas for further development. The suggested method was applied to evaluate the service quality in small and medium-sized hotels in Turkey and Azerbaijan, illustrated by the example

    A Geography of Strangeness: Transcultural Personhood and Fractal Identity in Contemporary South Asian Muslim American Literature

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    This dissertation carries out an epistemic inquiry of identity in South Asian Muslim American literature published in the twenty-first century. The selection of works analyzed includes five novels, two poetry collections, one memoir, and one collection of short stories, representing different narrative forms and styles by eight South Asian Muslim American writers. The authors have been selected for their work on the themes of displacement, identity, intergenerational conflict, gender, and religion, to highlight the transcultural nature of the literary works and present the fractal nature of the identity of literary characters and their discursive imaginations. The chosen literary publications examine a range of identity theory concepts coupled with the material and philosophical realities of the late modern world such as globalization, digital transformation, timespace compression, structuration, and reflexivity. Each author’s work is analyzed for the South Asian Muslim American diaspora’s response to the transformations, contradictions, and challenges confronting contemporary Islam as it moves forward in the twenty-first century. Far from normalizing the identity of these diasporic individuals, the focus of this dissertation is to present them as complex adaptive beings possessing and exhibiting fractal identities. Furthermore, by incorporating facets of the Muslim American identity and Islamic identity, which have their unique idiosyncrasies, worldviews, and cultural practices, this study attempts to present a more holistic view of contemporary South Asian Muslim Americans and their fiction. Therefore, the core of this project centers around the effects of displacement on identity formation moving towards an existential model of fractal identities in these transcultural diasporic individuals across generations, genders, and religion, highlighting sociologically and politically relevant themes.Departamento de Filología InglesaDoctorado en Estudios Ingleses Avanzados: Lenguas y Culturas en Contact

    American Transcendentalism Contra Contemporary Political Philosophy: Applications of Thomas Carlyle and Ralph Waldo Emerson to Liberal Democratic Capitalism, Platonism, Islamism, Technology, and the end of History

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    I construct Thomas Carlyle\u27s political philosophy in the contexts of twentieth-century and contemporary political philosophy by dialoging and contrasting Carlyle with the work of John Rawls, Alasdair MacIntyre, Jacques Ellul, and Sayyid Qutb, among others. I also focus my attention on Carlyle as a philosopher who is an intermediary between ancient Platonism and nineteenth-century American Transcendentalism. Carlyle\u27s Sartor Resartus is a Platonic text that provided a foundational inspiration for Ralph Waldo Emerson, Henry David Thoreau, and American Transcendentalism writ-large. Despite Carlyle being a chief source of inspiration for American Transcendentalism, his political theory did not inspire the development of a widely adopted political ideology to compete alongside other prominent twentieth-century ideologies such as liberalism, Marxism, fascism, and Islamism. It is in this context that Carlyle is also relevant in the philosophical inquiry of the end of history, or the ascertaining of the last stage of human political development. I argue that this is because Carlyle\u27s philosophical account of transcendentalism in Sartor Resartus can be constructed as post-liberalism, an ideology that reforms liberalism by seeking to stem its facilitation of increasing levels of economic inequality and increasing levels of political conflict on the bases of race, class, religion, etc. I apply Carlyle\u27s philosophy to build on literature that theorizes about post-liberalism by authors such as Patrick Deneen, John Milbank, and Adrian Pabst, who argue that liberalism is on a hazardous trajectory and there is a need to conceive of post-liberalism as an alternative to the trend of increasing authoritarianism

    Investigating and mitigating the role of neutralisation techniques on information security policies violation in healthcare organisations

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    Healthcare organisations today rely heavily on Electronic Medical Records systems (EMRs), which have become highly crucial IT assets that require significant security efforts to safeguard patients’ information. Individuals who have legitimate access to an organisation’s assets to perform their day-to-day duties but intentionally or unintentionally violate information security policies can jeopardise their organisation’s information security efforts and cause significant legal and financial losses. In the information security (InfoSec) literature, several studies emphasised the necessity to understand why employees behave in ways that contradict information security requirements but have offered widely different solutions. In an effort to respond to this situation, this thesis addressed the gap in the information security academic research by providing a deep understanding of the problem of medical practitioners’ behavioural justifications to violate information security policies and then determining proper solutions to reduce this undesirable behaviour. Neutralisation theory was used as the theoretical basis for the research. This thesis adopted a mixed-method research approach that comprises four consecutive phases, and each phase represents a research study that was conducted in light of the results from the preceding phase. The first phase of the thesis started by investigating the relationship between medical practitioners’ neutralisation techniques and their intention to violate information security policies that protect a patient’s privacy. A quantitative study was conducted to extend the work of Siponen and Vance [1] through a study of the Saudi Arabia healthcare industry. The data was collected via an online questionnaire from 66 Medical Interns (MIs) working in four academic hospitals. The study found that six neutralisation techniques—(1) appeal to higher loyalties, (2) defence of necessity, (3) the metaphor of ledger, (4) denial of responsibility, (5) denial of injury, and (6) condemnation of condemners—significantly contribute to the justifications of the MIs in hypothetically violating information security policies. The second phase of this research used a series of semi-structured interviews with IT security professionals in one of the largest academic hospitals in Saudi Arabia to explore the environmental factors that motivated the medical practitioners to evoke various neutralisation techniques. The results revealed that social, organisational, and emotional factors all stimulated the behavioural justifications to breach information security policies. During these interviews, it became clear that the IT department needed to ensure that security policies fit the daily tasks of the medical practitioners by providing alternative solutions to ensure the effectiveness of those policies. Based on these interviews, the objective of the following two phases was to improve the effectiveness of InfoSec policies against the use of behavioural justification by engaging the end users in the modification of existing policies via a collaborative writing process. Those two phases were conducted in the UK and Saudi Arabia to determine whether the collaborative writing process could produce a more effective security policy that balanced the security requirements with daily business needs, thus leading to a reduction in the use of neutralisation techniques to violate security policies. The overall result confirmed that the involvement of the end users via a collaborative writing process positively improved the effectiveness of the security policy to mitigate the individual behavioural justifications, showing that the process is a promising one to enhance security compliance
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