16,877 research outputs found

    A design tool for high-resolution high-frequency cascade continuous- time Σ∆ modulators

    Get PDF
    Event: Microtechnologies for the New Millennium, 2007, Maspalomas, Gran Canaria, SpainThis paper introduces a CAD methodology to assist the de signer in the implementation of continuous-time (CT) cas- cade Σ∆ modulators. The salient features of this methodology ar e: (a) flexible behavioral modeling for optimum accuracy- efficiency trade-offs at different stages of the top-down synthesis process; (b) direct synthesis in the continuous-time domain for minimum circuit complexity and sensitivity; a nd (c) mixed knowledge-based and optimization-based architec- tural exploration and specification transmission for enhanced circuit performance. The applicability of this methodology will be illustrated via the design of a 12 bit 20 MHz CT Σ∆ modulator in a 1.2V 130nm CMOS technology.Ministerio de Ciencia y Educación TEC2004-01752/MICMinisterio de Industria, Turismo y Comercio FIT-330100-2006-134 SPIRIT Projec

    Developing communication tools for resource management in western Alaska: an evaluation of the Western Alaska Landscape Conservation Cooperative coastal projects database

    Get PDF
    Master's Project (M.S.) University of Alaska Fairbanks, 2017Science communication is an essential component in decision-making for resource management in Alaska. This field aids in bridging knowledge gaps between scientists and diverse stakeholders. In 2014, the Western Alaska LCC developed a database cataloging the current coastal change projects in order to facilitate collaboration amongst researchers, managers, and the surrounding communities. In order to better inform similar outreach projects in other LCC regions, this MNRM project entailed an evaluation of this database between April and September 2016 and comprised a ten-question phone interview with the database participants and other involved personnel. Results from this evaluation can help refine the database to better suit its users' needs in the future, and it can also inform the creation of similar tools in other LCC regions. This project evaluated the use and usability of the Western Alaska LCC Coastal Change Database. First, I review coastal change and its impacts on Western Alaska. Next, I explore how institutions can respond to these changes and what resources they can use, including decision-support tools. I then provide examples of different decision-support tools (both in academic literature and in Alaskan projects) and discuss methodologies for evaluating their use. Interview results are then reported. The evaluation of the WALCC Coastal Change Database indicated that the tool was mostly used to enhance general understanding of the research occurring in the region. Respondents were less likely to use it for time-intensive tasks such as collaboration. Respondents also indicated that a place exists for tools like this database to flourish, but they need 1) persistent outreach, 2) a dynamic design, and 3) immediate benefits for users' time. In the future, regular updates and frequent outreach could improve the database's usability and help maintain its credibility

    A Framework for Synthesizing Agent-Based Heterogeneous Population Model for Epidemic Simulation

    Get PDF
    Social interactions play an important role in spread of a disease. In this thesis we propose a probabilistic approach to synthesize an agent-based heterogeneous population interaction model to study the spatio-temporal dynamics of an air-born epidemic, such as influenza, in a metropolitan area. The proposed methodology is generic in nature and can generate a baseline population for the cities for which detailed population summary tables are not available. The joint probabilities of population demographics are estimated using the International Public Use Microsimulation Data (IPUMS) sample data set. Based on the population density and the socio-economic status, the population is divided into three types of residential areas. Agents, representing individuals, are assigned various activities based on their education, age, and gender. Since transportation can also influence the spread of a disease, this activity, with a finite time span, is also assigned to individuals. The proposed approach is used for the city of Lahore, Pakistan. The agent-based model for Lahore is synthesized and a rule based disease spread model of influenza is simulated for the city population. The simulation results are visualized to analyze the spatio-temporal dynamics of an influenza epidemic for Lahore

    Digital Health Data Imperfection Patterns and Their Manifestations in an Australian Digital Hospital

    Get PDF
    Whilst digital health data provides great benefits for improved and effective patient care and organisational outcomes, the quality of digital health data can sometimes be a significant issue. Healthcare providers are known to spend a significant amount of time on assessing and cleaning data. To address this situation, this paper presents six Digital Health Data Imperfection Patterns that provide insight into data quality issues of digital health data, their root causes, their impact, and how these can be detected. Using the CRISP-DM methodology, we demonstrate the utility and pervasiveness of the patterns at the emergency department of Australia's major tertiary digital hospital. The pattern collection can be used by health providers to identify and prevent key digital health data quality issues contributing to reliable insights for clinical decision making and patient care delivery. The patterns also provide a solid foundation for future research in digital health through its identification of key data quality issues, root causes, detection techniques, and terminology

    Understanding Positive Aspects of the Caregiver Experience in Dementia: A Meta-Integration and Qualitative Investigation

    Get PDF
    This dissertation includes two studies designed to explore the positive aspects of providing care to someone living with dementia. The work reported here provides a knowledge base that benefits future research by allowing for a greater degree of consistency in labels, measures, and definitions of positive aspects, as well as by informing theoretical models of caregiving. The label ‘positive aspects’ is used in this work to refer to experiences or outcomes that are perceived by a caregiver to be positive in nature, and related to fulfilling the caregiver role. Study one is a meta-integration of the quantitative and qualitative research on the positive aspects of caregiving for someone living with dementia. Eight databases were systematically searched, and 80 studies were included in the study. Quantitative dataset synthesis revealed common relationships between measures of positive aspects and other caregiving factors. Qualitative dataset synthesis revealed factors that underlie, facilitate, and hinder positive aspects. Synthesizing the qualitative and quantitative datasets I elaborated on relationships between caregiving factors and provided a holistic account of the phenomenon, including conditions for the experience of positive aspects of caregiving. Study two is a qualitative investigation into caregivers’ perceptions and experiences of positive aspects of caring for someone living with dementia. The findings from study two lend support to study one findings of the factors that underlie, facilitate, and hinder the experience of positive aspects of caregiving. Study two findings provide insight into the relationship between positive aspects of caregiving and caregiver age, caregiver/care recipient relationship, and years spent caregiving. The findings of this dissertation may be used to inform models of caregiving, future research, and caregiver intervention programs. Through this work I elaborate on how caregiver factors, caregiving environment factors, and the complex interplay between the two impact caregivers’ experience of caregiving. I suggest the use of neutral models of caregiving that emphasize caregiver appraisal of the caregiving experience, as opposed to models of negative or models of positive caregiving outcomes. These findings highlight facilitating positive appraisal of the caregiving role and caregiving demands as a point of intervention for caregivers

    The fine structure of asset returns: an empirical investigation

    Get PDF
    We investigate the importance of diffusion and jumps in a new model for asset returns. In contrast to standard models, we allow for jump components displaying finite or infinite activity and variation. Empirical investigations of time series indicate that index dynamics are devoid of a diffusion component, which may be present in the dynamics of individual stocks. This leads to the conjecture, confirmed on options data, that the risk-neutral process should be free of a diffusion component. We conclude that the statistical and risk-neutral processes for equity prices are pure jump processes of infinite activity and finite variation
    corecore