15 research outputs found

    Understanding Statistics and Experimental Design

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    This open access textbook provides the background needed to correctly use, interpret and understand statistics and statistical data in diverse settings. Part I makes key concepts in statistics readily clear. Parts I and II give an overview of the most common tests (t-test, ANOVA, correlations) and work out their statistical principles. Part III provides insight into meta-statistics (statistics of statistics) and demonstrates why experiments often do not replicate. Finally, the textbook shows how complex statistics can be avoided by using clever experimental design. Both non-scientists and students in Biology, Biomedicine and Engineering will benefit from the book by learning the statistical basis of scientific claims and by discovering ways to evaluate the quality of scientific reports in academic journals and news outlets

    EUROCOMB 21 Book of extended abstracts

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    Optimisation of Natural Laminar Flow Aerofoils and Wings for Robustness to Critical Transition Amplification Factor

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    This thesis investigates the use of robust design and optimisation methods to improve natural laminar flow (NLF) aerofoil and wing robustness to variations both in operating conditions and uncertainty in surface and flow quality. NLF is a promising method for aircraft drag reduction but has high sensitivity to operating conditions, flow quality and surface finish. Existing research on this topic has looked to improve NLF designs at a range of operating conditions, but uncertainty in surface and flow quality has not been considered. In this work, surface and flow quality are represented by the critical transition amplification factor, or N-factor, from the eN transition model. A probabilistic distribution and quantification method for uncertainty in critical N-factor is first selected. This is then used to assess NLF aerofoil performance with uncertainty in critical N-factor. Transition location sensitivity to critical N-factor is found to be linked to transition location sensitivity to lift coefficient; and drag robustness is found to be closely related to transition location robustness. Robust optimisation is then used to design NLF aerofoils that are insensitive to uncertainty in critical N-factor. This is found to be effective; however, the robustness at off-design flight conditions deteriorates as a result. Many designs with no laminar flow are also generated. These are inherently robust to critical N-factor uncertainty but of no practical use. A method is then developed that enables the coupling of multi-point and robust optimisation without an increase in computational costs. This uses the N-factor envelope from eN stability analysis to predict transition locations over the critical N-factor range. Multi-point robust optimisation of NLF aerofoils with critical N-factor uncertainty is then carried out. This is able to produce NLF aerofoils with good robustness to critical N-factor uncertainty over a range of lift coefficients and Mach numbers. This envelope sampling method is then extended to account for three-dimensional flows and is used to optimise swept and tapered wing sections for NLF with uncertainty in critical N-factor. Overall, this work demonstrates that robust design and optimisation method are well suited to the design of NLF aerofoils and wings. Furthermore, it shows that the N-factor envelope from eN stability analysis can be used to reduce the dimensionality of robust NLF design, making it no more computationally expensive than current multi-point optimisation problems. It therefore makes an original contribution to the field of NLF design and optimisation

    Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress

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    Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018

    The Relationship between African- American Male Education and Employment Opportunities Through the Lenses of Critical Race Theory and Stereotype Threat in the Historical Context of the 1965 Moynihan Report

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    The purpose of this study is to examine the connection between education and employment outcomes for African American males through the dual lenses of Critical Race Theory (CRT) and Stereotype Threat (ST) in the historical context of the 1965 Moynihan Report. A qualitative case study design allowed for the collection of rich data through in-depth interviews designed to elicit the Black male participants’ perspectives and lived experience of education and employment. For more than fifty years, the trajectory of African American male education and employment has been a negative one. This study documented, in their own voice, the African American males’ viewpoint of education and job opportunities at various education levels. There are studies that show the persistent education gap between Black males and their non - Black cohorts. In addition, there are studies that show a similarly persistent gap between Black male and White male employment. However, few studies have used a qualitative approach that sought to hear from Black males directly. This study will help fill that gap by interviewing and gathering artifacts from 8 Black males at six levels of education; high school dropout, high school graduate, community college graduate, and college graduates with a Bachelor’s degree, a Master’s degree, and or a Doctorate degree. The first chapter presented the problem statement, background on the problem, a statement of purpose, introduction to the research questions, some operational definitions, the conceptual frameworks, my connection to the study, a brief review of the topic literature, a brief review of case study method, limitations of the study, and the significance of the study. Chapter 2 reviewed the relevant literature on the state of the problem, starting with a brief history of Black male education and employment in America since slavery. The chapter then reviewed the relevant literature on the dual conceptual frameworks, and the Moynihan report as historical context for the study. Next, chapter 2 reviewed relevant studies on Black male education and employment. Chapter 2 summarized the status of Black males in order to set the stage for this research examining the Black male perspective through the lens of Critical Race Theory and Stereotype Threat. Chapter 3 reiterated the conceptual frameworks of CRT and ST, in the context of Moynihan Report. The rationale for choosing the qualitative research methodology and the multi-case study design was outlined. The paper explained the role of the researcher, elaborated the research questions, and described the participants, relevant ethics, data collections, data analysis, and timeline. Chapter 4 showed the findings of the participants lived experiences including portraits of the eight participants, method of analysis, the five themes derived from the data; education, family, neighborhood, jobs and racism. Chapter 5 examined discussions, conclusions, and recommendation from the data. A findings analysis was conducted which answers the research questions, relating the findings to Critical Race Theory, to Stereotype Threat, and historical context of the Moynihan Report. The chapter closed with the limitations of the study, implications for future research, and recommendations for policy

    Linear TV In The Non-Linear World: The Value of Linear Scheduling Amidst the Proliferation of Non-Linear Platforms

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    Unprecedented technological innovations in media content consumption have had a profound impact on the network television industry. Television networks' control has waned since the advent of alternative platforms for content viewing. Audiences have been released from the clutches of the linear schedule. They now have the freedom to customize viewing based on their content and platform preferences, and availability. The purpose of this qualitative study is to assess 1) the current value of television linear scheduling and 2) the effectiveness of traditional strategies in this present phase of channel and platform proliferation. An additional goal is to identify new strategies that are employed by broadcasters to accommodate the audience's changing viewing habits. Thus, the author primarily interviewed experienced television executives who were currently in-charge of scheduling television shows. Their insights have led to the conclusion that scheduling remains relevant in this age of non-linear viewing. However, its functions adapt and its scope expands beyond linear. There are also key changes in the approaches and thought-processes in scheduling. Furthermore, new systems have been identified, which are currently utilized in attracting audiences to consume content via live television. As television insiders have differing opinions, it is suggested that the effectiveness of these new systems be researched further. Keywords: television scheduling, television programming, linear scheduling, lead-in, non-linear viewingM.S., Television Management -- Drexel University, 201

    Using MapReduce Streaming for Distributed Life Simulation on the Cloud

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    Distributed software simulations are indispensable in the study of large-scale life models but often require the use of technically complex lower-level distributed computing frameworks, such as MPI. We propose to overcome the complexity challenge by applying the emerging MapReduce (MR) model to distributed life simulations and by running such simulations on the cloud. Technically, we design optimized MR streaming algorithms for discrete and continuous versions of Conway’s life according to a general MR streaming pattern. We chose life because it is simple enough as a testbed for MR’s applicability to a-life simulations and general enough to make our results applicable to various lattice-based a-life models. We implement and empirically evaluate our algorithms’ performance on Amazon’s Elastic MR cloud. Our experiments demonstrate that a single MR optimization technique called strip partitioning can reduce the execution time of continuous life simulations by 64%. To the best of our knowledge, we are the first to propose and evaluate MR streaming algorithms for lattice-based simulations. Our algorithms can serve as prototypes in the development of novel MR simulation algorithms for large-scale lattice-based a-life models.https://digitalcommons.chapman.edu/scs_books/1014/thumbnail.jp

    Journal of the Senate of the 77th GA 2 Vol. 2 of the State of Iowa, 1998

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    The published daily journals of the transactions of the Senate for the legislative session and the official bound journals printed after adjournment for previous legislative sessions
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