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Comparative Analysis of Marine Structural End ConnectionsSilewicz, Bret 20 December 2009 (has links)
Numerous structural end connections are utilized everyday in the marine industry for ship design and/or maintenance. End connection design has been developed in earlier vessel designs and adapted as a general standard for all vessels being designed / built at a facility. Usually the supporting calculations developed to analyze the structural end connection are not available for engineers to re-examine. Furthermore, young engineers employ un-proven end connections in their designs, using the justification “It has been done like this in the past, it should work.†In this thesis, the author concentrates on finite element analysis for thirteen typical end connections used in the marine industry and correlated the shear and moment transfer to an AISC developed empirical beam equation for comparison. The author will rely on first principle equations and finite element analysis to prove the efficiency of various end connections, and draw comparative conclusions per each end connection analyzed.
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Investigation and control of three-dimensional separation/stall in compressorsSun, Jinjing 29 January 2018 (has links)
Pas de résumé / As one of the key components in the modern propulsion system, compressor plays an important role on the performance of the aero-engine. Flow near the endwall in the compressor is complex and corner separation which generates at the corner region by the blade suction surface and the endwall is an inherent flow structure in the blade passage. As a reduction of the compressor performance can be caused by the corner separation especially at off-design and multi-stage conditions. Understanding the mechanism and also control of the corner separation is an effective approach to enhance the compressor stability. Mechanism and control methods of the corner separation in the cascade passage have been investigated in this thesis, following contents are included: l. Simulation by the RANS methods on a highly-loaded PVD cascade has been conducted. The numerical method used is verified by the comparison with the experiment. The topology analysis, overall performance and the flow characteristics of the corner separation are analyzed. The effects of some aerodynamic parameters such as the solidity, aspect ratio and blade fillet on the corner separation have also been studied. 2. The control effects of one active control method by the boundary layer suction and two passive control methods by the slot at the root of the blade and the hub clearance on the corner separation in PVD cascade are studied and compared systematically. The slot configuration on the blade combined under the influence of the aerodynamic parameters have also been conducted in order to know the cascade performance by the aerodynamic parameters under the introduction of the control method. 3. Optimization of the slot configuration at 4° incidence angle is conducted on the NACA65 cascade of LMFA in Lyon. The optimized slotted cascade is verified by the experiment at three incidence angle. 4. DDES method based on the SST k - ω model is used to simulate the optimized NACA65 slotted cascade. The turbulent characteristics in the corner separation and slot jet flow are analyzed, such as the turbulent anisotropy and the velocity spectra. 5. The study of the slot configuration on the corner separation is carried out on a realistic fan stator with high loading and high Mach number. The feasibility and effectiveness of this passive control method in the practical engineering are verified.
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Physician-Perceived Challenges in End of Life CareStumpf, Carina 23 January 2019 (has links)
Background: Multiple factors influence end of life care and can lead to barriers in the experience of care for patients and the delivery of care for physicians. It is vital to determine the possible challenges physicians may face in providing end of life care in order to understand and decrease these challenges. Objective: The purpose of this study was to identify and understand the different challenges physicians face in the provision of quality end of life care. Methods: First, a scoping review was conducted on five databases to gather knowledge on the current literature on physician-perceived challenges in end of life care. Subsequently, a secondary data analysis was performed from the results of a pan-Canadian study with 1 060 respondents on medical end of life practices to: (1) measure the frequency of physician-perceived challenges based on the last patient who died under their care in the last 12 months, and (2) assess the relationship between the challenges and the physician’s or patient’s sociodemographic characteristics. Results: The results of the scoping review on 40 studies identified ten challenges: physician’s characteristics, family issues, team conflicts, team and family conflicts, institutional and organizational factors, training and educational factors, religious challenges, ethnicity and value-related challenges, human rights issues, and language challenges. Results from the secondary data analysis revealed that 26.9% of physicians reported at least one challenge, such as family conflicts, in the provision of end of life care with the last patient who died under their care in the last 12 months. Conclusion: These challenges restrict quality end of life care. As such, targeted strategies should be implemented to mitigate these barriers to end of life care and improve care.
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Front-end of innovation: roles and integration mechanisms / Front-end da inovação: papéis e mecanismos de integraçãoSchreiner, Lilian Cristina 08 May 2018 (has links)
The Front End of Innovation (FEI) is the early phase of the Product Development Process, responsible for the concept generation and an important driver of innovation success. The FEI is characterized by roles\' dynamism, ambiguity, and uncertainty. Several authors divide the FEI into other sub-phases in order to organize its activities, roles, and understand the function of each role. Despite the growing research about the FEI in recent years, there is a need for further research on the theme to better understand the dynamics and help to reduce the uncertainty in the critical concept phase. The formal processes designed for the front end are insufficient, the rules and roles are not fully described, and it is necessary to balance the interactions between the activities in the FEI to get a better-structured New Product Development - NPD - later. The main FEI models developed at the literature have discussed some key roles such marketing, engineering, customers, but they do not discussed the role of design, which is critical in creative activities which, in turn, are the nature of the new product development process. The literature also has not discussed the external integration in the FEI, that is, how the Brand Owners integrate the partners, especially the suppliers and design agencies, in this critical and uncertain phase. To tackle this issue, this research aims to examine the FEI in a dynamic industry, examining the integration of roles in an iterative process. The objective of this research is to identify the roles that play in the Front End of Innovation and the mechanisms of integration, whether internal through cross-functional teams; or external through interfirms integration. The main question that guided this research is \"What roles are involved in each FEI activity and what are the mechanism that integrate these roles in the FEI?\". This is qualitative and exploratory research, based on multiple-cases-studies. For this study, the packaging industry was selected because of its value chain in the concept phase, which has a complex set of relationships among its parties, Brand Owner, Design Agencies and Packaging Producers. The consumers buy the product by the performance of the same and also by the packaging. Packaging is considered a second product at the point of sale and a vital buying decision factor. Brand Owners understand that they need to integrate suppliers into the FEI to assist them in identifying opportunities, ideation, and conceptualization. Five brand owners were interviewed, and the FEI has been divided into five activities: Opportunity Identifications and Analysis, Idea Generation, Idea Enrichment, Idea Selection, and Concept Development. / O Front End de Inovação (FEI) é a fase inicial do processo de desenvolvimento de produtos, responsável pela geração de conceitos e um importante motor de sucesso na inovação. O FEI caracteriza-se pelo dinamismo, a ambiguidade e a incerteza dos papéis. Vários autores dividem o FEI em outras subfases, a fim de organizar suas atividades, papéis e compreender a função de cada função. Apesar da crescente pesquisa sobre o FEI nos últimos anos, há necessidade de novas pesquisas sobre o assunto para entender melhor a dinâmica e ajudar a reduzir a incerteza na fase conceitual crítica. Os processos formais projetados para o front-end são insuficientes, os papéis e as regras e não são totalmente descritos e é necessário equilibrar as interações entre as atividades no FEI para obter um melhor estruturado Desenvolvimento de Novos Produtos - NPD - depois. Os principais modelos de FEI desenvolvidos na literatura discutem alguns papéis fundamentais como marketing, engenharia, consumidores, mas não discutem o papel do design, crítico nas atividades criativas, que, por sua vez, são a natureza do processo de desenvolvimento de novos produtos. A literatura também não tem discutido a integração externa no FEI, ou seja, como os clientes integram os parceiros, especialmente os fornecedores e agências de design, nesta fase crítica e incerta. Para abordar esta questão, esta pesquisa visa examinar o FEI em uma indústria dinâmica, examinando a integração de papéis em um processo iterativo. O objetivo desta pesquisa é identificar os papéis que desempenham no Front End de Inovação e os mecanismos de integração, sejam eles internos através de equipes multifuncionais; ou externos através da integração entre firmas. A principal questão que guiou esta pesquisa é \"Quais papéis estão envolvidas em cada atividade do FEI e quais são os mecanismos que integram estes papéis no FEI?\" Trata-se de uma pesquisa qualitativa e exploratória, baseada em estudos de casos múltiplos. Para este estudo, o setor de embalagens foi selecionado por sua cadeia de valor na fase conceitual, que possui um conjunto complexo de relacionamentos entre suas partes, as Indústrias de Bens de Consumo, as Agências de Design e os Produtores de Embalagens. Os consumidores compram o produto pela performance do mesmo e também pela embalagem. A embalagem é considerada um segundo produto no ponto de venda e um fator de decisão de compra vital. As Indústrias de Bens de Consumo entendem que precisam integrar fornecedores no FEI para ajudá-las a identificar oportunidades, ideação e conceituação. Foram entrevistados cinco Indústrias de Bens de Consumo e o FEI foi dividido em cinco atividades: Identificações e Análises de Oportunidades, Geração de Ideias, Enriquecimento de Ideias, Seleção de Ideias e Desenvolvimento de Conceitos.
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The final chapter: end-of-life identity constructions in hospice narrative performancesPederson, Sarah Nicole 01 December 2012 (has links)
Through a post-colonial narrative turn, scholars created space for alternative illness narratives to be performed; narratives that reflected the fragmented and unpredictable ways of ailing bodies, and allowed for multiple and diverse identities to be constructed. However, even with this post-colonial turn, illness narratives in U.S. culture often depict situations in which individuals overcome their illnesses, and death is somehow avoided (Langellier & Peterson, 2004), which present potential constraints for what narratives individuals at the end-of-life (EOL) are able to tell and what identities they are able to construct. Using post-colonial narrative theory (Frank, 1995) as a framework, I engaged in a thematic narrative analysis of 16 hospice patient narratives, to understand whether narratives and identity constructions are constrained for dying individuals as they attempt to make sense of the end-of-life.
Patients constructed the five identities of the experienced individual, the believer, the ailing individual, the good dier, and the individual who is still living, through several themes. Ideals of both post-colonialism and modernism were present in identity constructions, suggesting some acceptance of alternative narratives for individuals at the EOL. However, notably a new type of colonization emerged as patients' identity constructions and themes reflected elements of ars moriendi or the good death (Faust, 2008). Specifically, it appears that end-of-life narratives must reflect that the individual nearing the end-of-life is doing so in a culturally acceptable way which involves acceptance, sacrificial or selfless qualities, dying gladly, and dying not alone. This nuanced type of colonization suggests that specific illness situations might present unique narrative colonization.
I end by offering practical implications for health care providers and family. Specifically, these findings might inform traditional practitioners and encourage them to broaden the clinical definition of the good death, with an understanding that elements such as esteem and emotional support or empowerment might be paramount for some patients' good deaths. Additionally, these findings offer awareness to family members regarding cultural expectations of the good death, so that they might consider whether they are adding pressure to their loved ones to achieve such a death.
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Transfer of prestress by pretensioned wire tendons.Kong, Paul Y.L. January 1993 (has links)
Key words: End zone, prestress transfer, wire tendon, transmission length, pull-in, plain wire, indented wire, concrete strength, size of wire, gradual release, sudden release, shock release, time dependent effects.An empirical investigation into the transfer of prestress force from wire tendons to concrete in the end zones of pretensioned prestressed concrete beams was accomplished in this project. The experimental tests featured 56 small scale prestressed concrete beams.Some of the factors influencing prestress transfer which were considered in the current tests are as follows:(a) type of release - gradual, sudden or shock(b) surface condition of the wire - plain or indented(c) size of the wire(d) concrete compressive strength at the time of transfer(e) time dependent effectsMost of the tests involved gradual release of steel tendons with the prestressing force transferred in approximately ten equal increments. Sudden release in a single step was achieved by allowing the supporting abutments to retract rapidly. Shock release was implemented in some beams by angle grinding the wires. The type of release which gave the best quality of prestress transfer was gradual release. This was followed by sudden and shock releases respectively.There were four types of wires used in the laboratory tests: namely the 5 mm dia. Plain, 5 mm dia. Chevron indented, 7 mm dia. Plain and 7 mm dia. Belgian indented wires. Transmission lengths were determined from strain distributions for these wires. Pull-ins of the wire tendons at the ends of the beams were also measured.There was significant scatter in the experimental data. Different ranges of transmission lengths and pull-ins were obtained for the various types of wires used.Three equations were derived for the 5 mm dia. Plain, 5 mm dia. Chevron and 7 mm dia. Plain wires, which linearly correlated pull-ins to the transmission lengths. ++ / These relationships provide a qualitative and quantitative method of indirectly monitoring for the transmission lengths through the measurements of pull-in.Statistical inference tests proved that indented wires were superior in performance compared to plain wires, but the differences were more apparent for the pull-ins than for the transmission lengths.Comparisons on the influence of tendon size substantiated that greater pull-ins occurred for larger wires but the differences were not significant for the transmission lengths.For concrete strength at the time of transfer of less than 32 MPa, the transmission lengths and pull-ins were significantly larger than those for higher strengths. It is recommended that concrete strength at transfer be at least 32 MPa for pretensioned prestressed concrete.Apart from the maturity and strength of concrete, the quality of a mix also influenced the transmission length and there was limited data to suggest that a better grade mix despite having lower strength at a more tender age could outperform a lower grade mix with greater strength released after a longer curing period.Formulae for plain and indented wires were found by dimensional analysis which correlated the transmission length to the diameter of wire tendon and the stress/strength ratio of the prestressed beams.Pull-ins increased significantly over 6 months but the changes in the transmission lengths were small. Normalised longitudinal strain distributions did not indicate that transmission lengths would remain unchanged over time.
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End-user assertions in forms/3 : an empirical studyWallace, Christine A. 23 August 2001 (has links)
Spreadsheets are arguably the most widely used programming language in use
today, yet spreadsheets commonly contain errors. Research shows that regardless
of the experience of the end user, an alarming number of spreadsheets contain
errors (91% in recent field audits). Most spreadsheets are created by end users with
little or no programming experience. Unfortunately, software engineering research
has largely ignored these users. In an attempt to reduce this high error rate, our
research is aimed at bringing the benefits of software engineering to end users
without requiring that they first learn software engineering principles. One
mechanism for creating error-free programs is assertions. An assertion is a program
property that always holds. It provides a way to attach more of the specification to
the program. We have developed an assertion tool for spreadsheet languages that
extends Microsoft Excel's validation scheme and includes capabilities such as
assertion propagation. This work describes an empirical study done to assess how
well end users understand and use the information provided by the assertion tool as
they perform maintenance tasks. The study also provides information about end
users' testing behavior. / Graduation date: 2002
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Reasoning about many-to-many requirement relationships in spreadsheet gridsBeckwith, Laura A. 18 November 2002 (has links)
Traditionally, research into end-user programming has focused on how to
make programming more accessible to end users. However, few researchers
have considered providing end users with devices to help improve the
reliability of the programs they create. To help improve the reliability of
spreadsheets created by end users, we are working to allow users to
communicate the purpose and other underlying information about their
spreadsheets using a form of requirement specifications we call "guards."
Guards were initially designed for individual cells but, for large spreadsheets,
with replicated/shared formulas across groups of rows or columns, guards can
only be practical if users can enter them across these groups of rows or
columns. The problem is, this introduces many-to-many relationships, at the
intersection of rows and columns with guards. It is not clear how the system
should reason and communicate about many-to-many relationships in a way
that will make sense to end users. In this thesis, we present the human-centric
design rationale for our approach to how the system should reason about such
many-to-many relationships. The design decisions are presented with their
reasons gleaned from two design-time models--Cognitive Dimensions and
Attention Investment--and from the users themselves in a small think-aloud
study. / Graduation date: 2003
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The lived experience of family caregivers who provided end-of-life care to a relative with advanced dementiaPeacock, Shelley 06 1900 (has links)
With aging of the baby boomer population, older adults living longer, and no known cure for dementia, the prevalence of dementia in older adults will inevitably rise. Dementia is a terminal illness, although it may not be recognized as such. Family caregivers to persons with dementia provide invaluable care, often at the expense of their own health and well-being. Over the past two decades there has been an abundance of research that examines the various and complex aspects of caring for a relative with dementia. However, there is a paucity of research that has been conducted on the experiences of family caregivers providing end-of-life care. The conceptual framework that guides this research is based on the work of Martin Heidegger.
A thorough search of the literature reveals that the main themes of this end-of-life experience studied to date are the experience of grief and loss, and the manifestations of depression in family caregivers. A number of gaps in the literature remain that limit our understanding of the end-of-life care experience. The purpose of the present study is to begin to address this neglected area of research. As a result, the research question is: What is the meaning of the lived experience of family caregivers who provided end-of-life care for a relative who died with advanced dementia? This question was addressed using an interpretive phenomenology based on the work of Munhall.
The study utilized a purposeful sample of family caregivers (n = 11) whose relative with dementia died in the last year. Two to three in-person, unstructured interviews were completed with each participant as a way to glean an understanding of their experiences and offer opportunities for the participant to verify their end-of-life caregiving story. A total of 27 interviews were recorded and transcribed verbatim. Transcripts were hermeneutically analyzed in order to create individual narratives for each participant, reveal the essence of this experience, discuss the influence of the life worlds, consider the taken for granted, and generate an overall study narrative. These findings reveal the complex nature of the end-of-life caregiving experience with dementia.
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Toward the standardization of use-wear studies: constructing an analogue to prehistoric hide workWiederhold, James Edward 30 September 2004 (has links)
This thesis is a use-wear study that deals with microwear on stone endscrapers used on one worked material: animal skins. The first part of the study defines and describes the process of rendering freshly skinned pelts into functional leather or rawhide products, addressing confusing terminology found in the literature as well. Problems with past use-wear experiments dealing with animal skins are also confronted and explained. The second part of the study examines endscrapers used to flesh and dehair bison hides and compares the use-wear traces left on the tool edge by each activity. This suite of characteristics is then compared to those found on an assemblage of Clovis-age scrapers from the Gault site in central Texas.
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