ERIC Educational Resources Information Center
Schuengel, C.; Sterkenburg, P. S.; Jeczynski, P.; Janssen, C. G. C.; Jongbloed, G.
2009-01-01
In a controlled multiple case design study, the development of a therapeutic relationship and its role in affect regulation were studied in 6 children with visual disabilities, severe intellectual disabilities, severe challenging behavior, and prolonged social deprivation. In the 1st phase, children had sessions with an experimental therapist…
A Multiple Case Study of Faculty Control over Course Design and Its Effect on Faculty Efficacy
ERIC Educational Resources Information Center
King, Tara
2017-01-01
Online education continues to grow and change and different colleges and universities have varying degrees of faculty control over course design. This multiple case study investigated patterns in the efficacy of faculty who teach online courses in relation to the faculty members' involvement in the creation of elements of course design. The…
Student Perceptions of Online Writing Center Designs for Fully Online Programs
ERIC Educational Resources Information Center
Simpson, Shelah Y.
2017-01-01
In this multiple-case study, the author investigated fully online students' perceptions of and experiences with asynchronous and synchronous writing support options of an institutional writing center and a commercial tutoring service. This dissertation used a multiple-case study design (Merriam, 1998, 2009; Yin, 2009) to ascertain which features…
Multiple Uses of a Word Study Technique
ERIC Educational Resources Information Center
Joseph, Laurice M.; Orlins, Andrew
2005-01-01
This paper presents two case studies that illustrate the multiple uses of word sorts, a word study phonics technique. Case study children were Sara, a second grader, who had difficulty with reading basic words and John, a third grader, who had difficulty with spelling basic words. Multiple baseline designs were employed to study the effects of…
Design and analysis of multiple diseases genome-wide association studies without controls.
Chen, Zhongxue; Huang, Hanwen; Ng, Hon Keung Tony
2012-11-15
In genome-wide association studies (GWAS), multiple diseases with shared controls is one of the case-control study designs. If data obtained from these studies are appropriately analyzed, this design can have several advantages such as improving statistical power in detecting associations and reducing the time and cost in the data collection process. In this paper, we propose a study design for GWAS which involves multiple diseases but without controls. We also propose corresponding statistical data analysis strategy for GWAS with multiple diseases but no controls. Through a simulation study, we show that the statistical association test with the proposed study design is more powerful than the test with single disease sharing common controls, and it has comparable power to the overall test based on the whole dataset including the controls. We also apply the proposed method to a real GWAS dataset to illustrate the methodologies and the advantages of the proposed design. Some possible limitations of this study design and testing method and their solutions are also discussed. Our findings indicate that the proposed study design and statistical analysis strategy could be more efficient than the usual case-control GWAS as well as those with shared controls. Copyright © 2012 Elsevier B.V. All rights reserved.
Department of Defense Ecosystem Management Policy Evaluation
2002-08-01
HQ Naval Facilities Engineering Command, DC • Tom Hillard, Fort Stewart, GA • Manual Joia , MCLB Barstow, CA • John Krupovage, Tinker AFB, OK...studies can follow single or multiple-case designs . Multiple cases strengthen the results and increase confidence in those results (Tellis 1997...groups having responsibility for maintaining their designated data layers (range, fish and wildlife, threatened and endangered species, forestry
Case-control analysis in highway safety: Accounting for sites with multiple crashes.
Gross, Frank
2013-12-01
There is an increased interest in the use of epidemiological methods in highway safety analysis. The case-control and cohort methods are commonly used in the epidemiological field to identify risk factors and quantify the risk or odds of disease given certain characteristics and factors related to an individual. This same concept can be applied to highway safety where the entity of interest is a roadway segment or intersection (rather than a person) and the risk factors of interest are the operational and geometric characteristics of a given roadway. One criticism of the use of these methods in highway safety is that they have not accounted for the difference between sites with single and multiple crashes. In the medical field, a disease either occurs or it does not; multiple occurrences are generally not an issue. In the highway safety field, it is necessary to evaluate the safety of a given site while accounting for multiple crashes. Otherwise, the analysis may underestimate the safety effects of a given factor. This paper explores the use of the case-control method in highway safety and two variations to account for sites with multiple crashes. Specifically, the paper presents two alternative methods for defining cases in a case-control study and compares the results in a case study. The first alternative defines a separate case for each crash in a given study period, thereby increasing the weight of the associated roadway characteristics in the analysis. The second alternative defines entire crash categories as cases (sites with one crash, sites with two crashes, etc.) and analyzes each group separately in comparison to sites with no crashes. The results are also compared to a "typical" case-control application, where the cases are simply defined as any entity that experiences at least one crash and controls are those entities without a crash in a given period. In a "typical" case-control design, the attributes associated with single-crash segments are weighted the same as the attributes of segments with multiple crashes. The results support the hypothesis that the "typical" case-control design may underestimate the safety effects of a given factor compared to methods that account for sites with multiple crashes. Compared to the first alternative case definition (where multiple crash segments represent multiple cases) the results from the "typical" case-control design are less pronounced (i.e., closer to unity). The second alternative (where case definitions are constructed for various crash categories and analyzed separately) provides further evidence that sites with single and multiple crashes should not be grouped together in a case-control analysis. This paper indicates a clear need to differentiate sites with single and multiple crashes in a case-control analysis. While the results suggest that sites with multiple crashes can be accounted for using a case-control design, further research is needed to determine the optimal method for addressing this issue. This paper provides a starting point for that research. Copyright © 2012 Elsevier Ltd. All rights reserved.
Empowering Students through Organizational Empathy: Multiple Case Study Methodology
ERIC Educational Resources Information Center
Williams, Daniel
2017-01-01
This dissertation in practice employed a multiple case study design to better understand how two executive directors within a national network of arts and technology educational organizations defined, nurtured, and measured empathy with in their students. Empathy can connect diverse people and improve relationships, and it has been proven to…
ERIC Educational Resources Information Center
Villalobos, Ricardo
2017-01-01
This explanatory qualitative study investigated the perspectives of participant's and practitioner's perceived barriers to success and the necessary navigational expertise for overcoming the identified barriers. This multiple-case study research design examined three WIA out-of-school youth workforce development programs in Southern Nevada, with…
A Multiple Case Study of Verbal Short-Term Memory in Velo-Cardio-Facial Syndrome
ERIC Educational Resources Information Center
Majerus, S.; Glaser, B.; Van der Linden, M.; Eliez, S.
2006-01-01
Background: Velo-cardio-facial syndrome (VCFS, 22q 11.2 deletion) is characterized by severely delayed language development. The current study explored the integrity of verbal short-term memory (STM), a cognitive function critically involved in language development, in eight children with VCFS. Methods: Using a multiple case study design, we…
The Best Practices for School Transformation: A Multiple-Case Study
ERIC Educational Resources Information Center
Waheed, Zarina; Hussin, Sufean; Bin Megat Daud, Megat Ahmad Kamaluddin
2018-01-01
Purpose: The purpose of this paper is to explore the best practices of school leaders, teachers, pupils, parents and the community in selected transformed schools in Selangor, Malaysia. Design/methodology/approach: This qualitative multiple-case study explores the best practices in two selected transformed schools through in-depth interviews,…
Interpersonal Consulting Skills for Instructional Technology Consultants: A Multiple Case Study
ERIC Educational Resources Information Center
van Leusen, Peter; Ottenbreit-Lefwich, Anne T.; Brush, Thomas
2016-01-01
Building a trust-based relationship with faculty is one of the most important attributes of effective Instructional Technology Consultants (ITC) in order to integrate emerging technologies into higher education. Utilizing a multiple case study research design, four experienced ITCs at a large urban research university located in the Midwest showed…
ERIC Educational Resources Information Center
Jung, Ji yoon
2017-01-01
The purpose of this study is to provide a comprehensive account on case-based instructional practices. Semester-long participant observation records in torts, marketing, and online instructional design classes, instructor interviews, course syllabi and teaching materials were used to describe the within-class complexity of the practices in terms…
A standardized mean difference effect size for multiple baseline designs across individuals.
Hedges, Larry V; Pustejovsky, James E; Shadish, William R
2013-12-01
Single-case designs are a class of research methods for evaluating treatment effects by measuring outcomes repeatedly over time while systematically introducing different condition (e.g., treatment and control) to the same individual. The designs are used across fields such as behavior analysis, clinical psychology, special education, and medicine. Emerging standards for single-case designs have focused attention on methods for summarizing and meta-analyzing findings and on the need for effect sizes indices that are comparable to those used in between-subjects designs. In the previous work, we discussed how to define and estimate an effect size that is directly comparable to the standardized mean difference often used in between-subjects research based on the data from a particular type of single-case design, the treatment reversal or (AB)(k) design. This paper extends the effect size measure to another type of single-case study, the multiple baseline design. We propose estimation methods for the effect size and its variance, study the estimators using simulation, and demonstrate the approach in two applications. Copyright © 2013 John Wiley & Sons, Ltd.
Team effectiveness in academic medical libraries: a multiple case study*
Russo Martin, Elaine
2006-01-01
Objectives: The objective of this study is to apply J. Richard Hackman's framework on team effectiveness to academic medical library settings. Methods: The study uses a qualitative, multiple case study design, employing interviews and focus groups to examine team effectiveness in three academic medical libraries. Another site was selected as a pilot to validate the research design, field procedures, and methods to be used with the cases. In all, three interviews and twelve focus groups, with approximately seventy-five participants, were conducted at the case study libraries. Findings: Hackman identified five conditions leading to team effectiveness and three outcomes dimensions that defined effectiveness. The participants in this study identified additional characteristics of effectiveness that focused on enhanced communication, leadership personality and behavior, and relationship building. The study also revealed an additional outcome dimension related to the evolution of teams. Conclusions: Introducing teams into an organization is not a trivial matter. Hackman's model of effectiveness has implications for designing successful library teams. PMID:16888659
Lalor, Joan G; Casey, Dympna; Elliott, Naomi; Coyne, Imelda; Comiskey, Catherine; Higgins, Agnes; Murphy, Kathy; Devane, Declan; Begley, Cecily
2013-04-08
The role of the clinical nurse/midwife specialist and advanced nurse/midwife practitioner is complex not least because of the diversity in how the roles are operationalised across health settings and within multidisciplinary teams. This aim of this paper is to use The SCAPE Study: Specialist Clinical and Advanced Practitioner Evaluation in Ireland to illustrate how case study was used to strengthen a Sequential Explanatory Design. In Phase 1, clinicians identified indicators of specialist and advanced practice which were then used to guide the instrumental case study design which formed the second phase of the larger study. Phase 2 used matched case studies to evaluate the effectiveness of specialist and advanced practitioners on clinical outcomes for service users. Data were collected through observation, documentary analysis, and interviews. Observations were made of 23 Clinical Specialists or Advanced Practitioners, and 23 matched clinicians in similar matched non-postholding sites, while they delivered care. Forty-one service users, 41 clinicians, and 23 Directors of Nursing or Midwifery were interviewed, and 279 service users completed a survey based on the components of CS and AP practice identified in Phase 1. A coding framework, and the generation of cross tabulation matrices in NVivo, was used to make explicit how the outcome measures were confirmed and validated from multiple sources. This strengthened the potential to examine single cases that seemed 'different', and allowed for cases to be redefined. Phase 3 involved interviews with policy-makers to set the findings in context. Case study is a powerful research strategy to use within sequential explanatory mixed method designs, and adds completeness to the exploration of complex issues in clinical practice. The design is flexible, allowing the use of multiple data collection methods from both qualitative and quantitative paradigms. Multiple approaches to data collection are needed to evaluate the impact of complex roles and interventions in health care outcomes and service delivery. Case study design is an appropriate methodology to use when study outcomes relate to clinical practice.
Implementing the Health Promoting School in Denmark: A Case Study
ERIC Educational Resources Information Center
Nordin, Lone Lindegaard
2016-01-01
Purpose: The purpose of this paper is to provide insight into teachers' practice in implementing school-based health promotion. Design/methodology/approach: This qualitative research was designed as a multiple case study. The study involved five schools, 233 pupils in the age 12-16 and 23 teachers. The primary data generation method were focus…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-07
... assessment. In some cases, a PMA may include multiple studies designed to answer different scientific... designing clinical studies intended to support premarket submissions for medical devices and for FDA staff who review those submissions. This guidance document describes different study design principles...
On Internal Validity in Multiple Baseline Designs
ERIC Educational Resources Information Center
Pustejovsky, James E.
2014-01-01
Single-case designs are a class of research designs for evaluating intervention effects on individual cases. The designs are widely applied in certain fields, including special education, school psychology, clinical psychology, social work, and applied behavior analysis. The multiple baseline design (MBD) is the most frequently used single-case…
ERIC Educational Resources Information Center
Wall, Kathleen Horner
2011-01-01
Accidents and fatalities at USA amusement parks are rare, yet when they do occur, they can injure, maim, and even kill. This dissertation sheds light on how three family-owned amusement parks learned and improved as organizations from their own and others' failure experience. Using a multiple case study design, 18 participants were interviewed.…
Understanding Decision Making in Teachers' Curriculum Design Approaches
ERIC Educational Resources Information Center
Boschman, Ferry; McKenney, Susan; Voogt, Joke
2014-01-01
The goal of this study was to reach a better understanding of the intuitive decisions teachers make when designing a technology-rich learning environment. A multiple case-study design was employed to examine what kinds of factors (external priorities, existing orientations or practical concerns) influence design interactions of teams of…
Rapid Prototyping in Instructional Design: Creating Competencies
ERIC Educational Resources Information Center
Fulton, Carolyn D.
2010-01-01
Instructional designers working in rapid prototyping environments currently do not have a list of competencies that help to identify the knowledge, skills, and attitudes (KSAs) required in these workplaces. This qualitative case study used multiple cases in an attempt to identify rapid prototyping competencies required in a rapid prototyping…
Balliu, Brunilda; Tsonaka, Roula; Boehringer, Stefan; Houwing-Duistermaat, Jeanine
2015-03-01
Integrative omics, the joint analysis of outcome and multiple types of omics data, such as genomics, epigenomics, and transcriptomics data, constitute a promising approach for powerful and biologically relevant association studies. These studies often employ a case-control design, and often include nonomics covariates, such as age and gender, that may modify the underlying omics risk factors. An open question is how to best integrate multiple omics and nonomics information to maximize statistical power in case-control studies that ascertain individuals based on the phenotype. Recent work on integrative omics have used prospective approaches, modeling case-control status conditional on omics, and nonomics risk factors. Compared to univariate approaches, jointly analyzing multiple risk factors with a prospective approach increases power in nonascertained cohorts. However, these prospective approaches often lose power in case-control studies. In this article, we propose a novel statistical method for integrating multiple omics and nonomics factors in case-control association studies. Our method is based on a retrospective likelihood function that models the joint distribution of omics and nonomics factors conditional on case-control status. The new method provides accurate control of Type I error rate and has increased efficiency over prospective approaches in both simulated and real data. © 2015 Wiley Periodicals, Inc.
Developing the DESCARTE Model: The Design of Case Study Research in Health Care.
Carolan, Clare M; Forbat, Liz; Smith, Annetta
2016-04-01
Case study is a long-established research tradition which predates the recent surge in mixed-methods research. Although a myriad of nuanced definitions of case study exist, seminal case study authors agree that the use of multiple data sources typify this research approach. The expansive case study literature demonstrates a lack of clarity and guidance in designing and reporting this approach to research. Informed by two reviews of the current health care literature, we posit that methodological description in case studies principally focuses on description of case study typology, which impedes the construction of methodologically clear and rigorous case studies. We draw from the case study and mixed-methods literature to develop the DESCARTE model as an innovative approach to the design, conduct, and reporting of case studies in health care. We examine how case study fits within the overall enterprise of qualitatively driven mixed-methods research, and the potential strengths of the model are considered. © The Author(s) 2015.
Ren, Jingzheng; Manzardo, Alessandro; Toniolo, Sara; Scipioni, Antonio; Tan, Shiyu; Dong, Lichun; Gao, Suzhao
2013-10-01
The purpose of this paper is to develop a model for designing the most sustainable bioethanol supply chain. Taking into consideration of the possibility of multiple-feedstock, multiple transportation modes, multiple alternative technologies, multiple transport patterns and multiple waste disposal manners in bioethanol systems, this study developed a model for designing the most sustainable bioethanol supply chain by minimizing the total ecological footprint under some prerequisite constraints including satisfying the goal of the stakeholders', the limitation of resources and energy, the capacity of warehouses, the market demand and some technological constraints. And an illustrative case of multiple-feedstock bioethanol system has been studied by the proposed method, and a global best solution by which the total ecological footprint is the minimal has been obtained. Copyright © 2013 Elsevier Ltd. All rights reserved.
Evaluating a Tacit Knowledge Sharing Initiative: A Case Study
ERIC Educational Resources Information Center
Gubbins, Claire; Corrigan, Siobhan; Garavan, Thomas N.; O'Connor, Christy; Leahy, Damien; Long, David; Murphy, Eamonn
2012-01-01
Purpose: This paper aims to present a case study illustrating the issues involved in the tacit knowledge conversion process and to determine whether such conversion delivers value to the organisation in terms of business value and return on investment (ROI). Design/methodology/approach: A single-case multiple baseline participants experimental…
Preparing Principals for Social Justice Leadership
ERIC Educational Resources Information Center
Baker-Martinez, Darcy
2012-01-01
The purpose of this study is to examine the experiences of social justice leaders to uncover specific leadership competencies that may inform current principal preparation programs. This study employed a qualitative multiple case study design. The three participants all shared many common strategies on how they manage the multiple forms of…
Barterian, Justin A; Sanchez, Joel M; Magen, Jed; Siroky, Allison K; Mash, Brittany L; Carlson, John S
2018-01-01
This study examined the utility of fluoxetine in the treatment of 5 children, aged 5 to 14 years, diagnosed with selective mutism who also demonstrated symptoms of social anxiety. A nonconcurrent, randomized, multiple-baseline, single-case design with a single-blind placebo-controlled procedure was used. Parents and the study psychiatrist completed multiple methods of assessment including Direct Behavior Ratings and questionnaires. Treatment outcomes were evaluated by calculating effect sizes for each participant as an individual and for the participants as a group. Information regarding adverse effects with an emphasis on behavioral disinhibition and ratings of parental acceptance of the intervention was gathered. All 5 children experienced improvement in social anxiety, responsive speech, and spontaneous speech with medium to large effect sizes; however, children still met criteria for selective mutism at the end of the study. Adverse events were minimal, with only 2 children experiencing brief occurrences of minor behavioral disinhibition. Parents found the treatment highly acceptable.
A Diagnostic Study of Pre-Service Teachers' Competency in Multiple-Choice Item Development
ERIC Educational Resources Information Center
Asim, Alice E.; Ekuri, Emmanuel E.; Eni, Eni I.
2013-01-01
Large class size is an issue in testing at all levels of Education. As a panacea to this, multiple choice test formats has become very popular. This case study was designed to diagnose pre-service teachers' competency in constructing questions (IQT); direct questions (DQT); and best answer (BAT) varieties of multiple choice items. Subjects were 88…
ERIC Educational Resources Information Center
Fielke, Simon J.; Botha, Neels; Reid, Janet; Gray, David; Blackett, Paula; Park, Nicola; Williams, Tracy
2018-01-01
Purpose: This paper highlights important lessons for co-innovation drawn from three ex-post case study innovation projects implemented within three sub-sectors of the primary industry sector in New Zealand. Design/methodology/approach: The characteristics that fostered co-innovation in each innovation project case study were identified from…
Enhancing the hermeneutic single-case efficacy design: Bridging the research-practice gap.
Wall, Jessie M; Kwee, Janelle L; Hu, Monica; McDonald, Marvin J
2017-09-01
Systematic case study designs are emerging as alternative paradigm strategies for psychotherapy and social science research. Through enhanced sensitivity to context, these designs examine idiographic profiles of causal processes. We specifically advocate the use of the hermeneutic single-case efficacy design (HSCED). HSCED has recently been used to investigate the efficacy of an existing therapy with a new population (Observed and Experiential Integration for athlete performance barriers) and an emerging therapy (Lifespan Integration Therapy). We describe innovations in HSCED that were implemented for these studies. These developments include (a) integrating psychotherapists as case developers, (b) incorporating multiple cases in one investigation, and (c) tailoring the repertoire of assessment tools. These extensions strategically incorporated principles of contextual paradigms in HSCED, thus complementing single-case designs that neglect idiographic contexts. We discuss recommendations for using HSCED in practice-based research, highlighting its potential as a bridge to address the research-practice gap.
Identifying Instructional Strategies Used to Design Mobile Learning in a Corporate Setting
ERIC Educational Resources Information Center
Jackson-Butler, Uletta
2016-01-01
The purpose of this qualitative embedded multiple case study was to describe what instructional strategies corporate instructional designers were using to design mobile learning and to understand from their experiences which instructional strategies they believed enhance learning. Participants were five instructional designers who were actively…
ERIC Educational Resources Information Center
Bickmore, Dana L.; Dowell, Margaret-Mary Sulentic
2011-01-01
As part of a multiple case study of charter school leadership, the researchers in this study examined 2 principals' priorities and practices through their expressed concerns and use of time. Through an embedded case design and analysis, 6 themes surfaced from the principal interviews that occurred over the course of a school year--accountability,…
ERIC Educational Resources Information Center
van Breda, John; Musango, Josephine; Brent, Alan
2016-01-01
Purpose: This paper aims to improve the understanding of individual transdisciplinary PhD research in a developing country context, focusing on three individual PhD case studies in South Africa. Design/Methodology/Approach: Multiple-case method was used, and three completed transdisciplinary PhD research efforts undertaken at the Stellenbosch…
ERIC Educational Resources Information Center
Lindstrom, Lauren; Hirano, Kara A.; McCarthy, Colleen; Alverson, Charlotte Y.
2014-01-01
This study examined career development and early employment experiences for four young adults with intellectual and developmental disabilities. Researchers used a multiple-method, multiple case-study longitudinal design to explore career development within the context of family systems, high school and transition programs, adult services, and…
ERIC Educational Resources Information Center
Chiu, Chung-Yi; Tansey, Timothy N.; Chan, Fong; Strauser, David; Frain, Michael P.; Arora, Simran
2015-01-01
Objectives: To examine the effect of rehabilitation technology interventions on the employment or job retention outcomes of individuals with multiple sclerosis (MS) served by the state-federal vocational rehabilitation program using a case-control study design. Participants: Data for this study were extracted from the Rehabilitation Services…
Multiple imputation of missing data in nested case-control and case-cohort studies.
Keogh, Ruth H; Seaman, Shaun R; Bartlett, Jonathan W; Wood, Angela M
2018-06-05
The nested case-control and case-cohort designs are two main approaches for carrying out a substudy within a prospective cohort. This article adapts multiple imputation (MI) methods for handling missing covariates in full-cohort studies for nested case-control and case-cohort studies. We consider data missing by design and data missing by chance. MI analyses that make use of full-cohort data and MI analyses based on substudy data only are described, alongside an intermediate approach in which the imputation uses full-cohort data but the analysis uses only the substudy. We describe adaptations to two imputation methods: the approximate method (MI-approx) of White and Royston () and the "substantive model compatible" (MI-SMC) method of Bartlett et al. (). We also apply the "MI matched set" approach of Seaman and Keogh () to nested case-control studies, which does not require any full-cohort information. The methods are investigated using simulation studies and all perform well when their assumptions hold. Substantial gains in efficiency can be made by imputing data missing by design using the full-cohort approach or by imputing data missing by chance in analyses using the substudy only. The intermediate approach brings greater gains in efficiency relative to the substudy approach and is more robust to imputation model misspecification than the full-cohort approach. The methods are illustrated using the ARIC Study cohort. Supplementary Materials provide R and Stata code. © 2018, The International Biometric Society.
ERIC Educational Resources Information Center
Saltan, Fatih; Özden, M. Yasar; Kiraz, Ercan
2016-01-01
People generally prefer to use stories in order to provide context when expressing a point. Spreading a message without context is unlikely to be meaningful. Like stories, cases have contextual meaning and allow learners to see a situation from multiple perspectives. The main purpose of the present study was to investigate how to design and…
Design-Comparable Effect Sizes in Multiple Baseline Designs: A General Modeling Framework
ERIC Educational Resources Information Center
Pustejovsky, James E.; Hedges, Larry V.; Shadish, William R.
2014-01-01
In single-case research, the multiple baseline design is a widely used approach for evaluating the effects of interventions on individuals. Multiple baseline designs involve repeated measurement of outcomes over time and the controlled introduction of a treatment at different times for different individuals. This article outlines a general…
Triggering Transformative Possibilities: A Case Study of Leaders' Quest in China
ERIC Educational Resources Information Center
Lau-Kwong, Kenzie
2012-01-01
This study explored the nature of transformative learning experiences among global executives who participated in Quest program, a learning journey program designed to facilitate shifting mind-sets and worldviews through 1-week intensives in countries such as China. A mixed methods, multiple case study approach was employed. First, a secondary…
Factors Affecting Pre-Service Teachers' Participation in Asynchronous Discussion: The Case of Iran
ERIC Educational Resources Information Center
Ebrahimi, Alice; Faghih, Esmail; Marandi, Seyyedeh Susan
2016-01-01
This study reports on a qualitative small-scale exploratory study which examined the factors influencing 32 Iranian pre-service language teachers' participation in online asynchronous text-based discussion forums. By adopting a multiple case study design and analysing data gathered through semi-structured interviews and participants' online…
Barlow, D H; Hayes, S C
1979-01-01
A little used and often confused design, capable of comparing two treatments within a single subject, has been termed, variously, a multielement baseline design, a multiple schedule design, and a randomization design. The background of these terms is reviewed, and a new, more descriptive term, Alternating Treatments Design, is proposed. Critical differences between this design and a Simultaneous Treatment Design are outlined, and experimental questions answerable by each design are noted. Potential problems with multiple treatment interference in this procedure are divided into sequential confounding, carryover effects, and alternation effects and the importance of these issues vis-a-vis other single-case experimental designs is considered. Methods of minimizing multiple treatment interference as well as methods of studying these effects are outlined. Finally, appropriate uses of Alternating Treatments Designs are described and discussed in the context of recent examples. PMID:489478
NASA Astrophysics Data System (ADS)
Beiden, Sergey V.; Wagner, Robert F.; Campbell, Gregory; Metz, Charles E.; Chan, Heang-Ping; Nishikawa, Robert M.; Schnall, Mitchell D.; Jiang, Yulei
2001-06-01
In recent years, the multiple-reader, multiple-case (MRMC) study paradigm has become widespread for receiver operating characteristic (ROC) assessment of systems for diagnostic imaging and computer-aided diagnosis. We review how MRMC data can be analyzed in terms of the multiple components of the variance (case, reader, interactions) observed in those studies. Such information is useful for the design of pivotal studies from results of a pilot study and also for studying the effects of reader training. Recently, several of the present authors have demonstrated methods to generalize the analysis of multiple variance components to the case where unaided readers of diagnostic images are compared with readers who receive the benefit of a computer assist (CAD). For this case it is necessary to model the possibility that several of the components of variance might be reduced when readers incorporate the computer assist, compared to the unaided reading condition. We review results of this kind of analysis on three previously published MRMC studies, two of which were applications of CAD to diagnostic mammography and one was an application of CAD to screening mammography. The results for the three cases are seen to differ, depending on the reader population sampled and the task of interest. Thus, it is not possible to generalize a particular analysis of variance components beyond the tasks and populations actually investigated.
Learning on the Fly: Exploring the Informal Learning Process of Aviation Instructors
ERIC Educational Resources Information Center
Wofford, Michael Grant; Ellinger, Andrea D.; Watkins, Karen E.
2013-01-01
Purpose: This study aims to examine the process of informal learning of aviation instructors. Design/methodology/approach: A qualitative instrumental case study design was used for this study. In-depth, multiple semi-structured interviews and document review were the primary approaches to data collection and the data were analyzed using constant…
ERIC Educational Resources Information Center
Ok, Min Wook; Bryant, Diane Pedrotty
2016-01-01
This study investigated the effects of explicit, strategic intervention with iPad application practice on the multiplication fact performance and strategy use of elementary students with learning disabilities (LD) using a single-case, multiple probe design across participants. Four fifth-grade students with LD received 15 1:1 intervention sessions…
A Case Study on Multiple-Choice Testing in Anatomical Sciences
ERIC Educational Resources Information Center
Golda, Stephanie DuPont
2011-01-01
Objective testing techniques, such as multiple-choice examinations, are a widely accepted method of assessment in gross anatomy. In order to deter cheating on these types of examinations, instructors often design several versions of an examination to distribute. These versions usually involve the rearrangement of questions and their corresponding…
ERIC Educational Resources Information Center
Haakma, Ineke; Janssen, Marleen; Minnaert, Alexander
2016-01-01
Because little is known about teacher-student relationships that involve students with acquired deafblindness, the authors performed a multiple case study with a multiple-method design to investigate the relationship between need-supportive teaching behaviors and student engagement. Using self-determination theory (Deci & Ryan, 2000), they…
A Case Study Framework for Community College Leaders
ERIC Educational Resources Information Center
Nevarez, Carlos; Wood, J. Luke
2012-01-01
This article examines a case study framework designed to aid in the preparation of emerging community college leaders. The framework is multidimensional and fluid in nature, taking into account the multiplicity of factors affecting leadership in community colleges. The steps in the framework consist of (a) assuming the role of the leader; (b)…
Alternative approaches to analytical designs in occupational injury epidemiology.
Mittleman, M A; Maldonado, G; Gerberich, S G; Smith, G S; Sorock, G S
1997-08-01
In this paper, we discuss the theoretical framework upon which observational studies of occupational injuries are based. Following a general description of how causal effects are estimated, the challenges faced by researchers working in this area are outlined, with an emphasis on case-control studies. These challenges include defining the at-risk period for workers whose tasks change over time and whose hazard period may be very brief, evaluating the underreporting of both exposures and injuries, and considering the effects of multiple injuries per individual on study design and data analysis. We review both the theoretical and practical considerations in the design and conduct of traditional case-control studies, based on the collection of individual level data, as well as other approaches, such as using information culled from administrative and descriptive databases, and case-control studies in which the plant or work site is the unit of analysis. The case-crossover design is also reviewed and its utility for reducing confounding due to differences between individuals by self-matching is highlighted. While this design has not yet been applied to the work setting, its potential for increasing our understanding of the causes of acute-onset occupational injuries seems promising. Finally, a variety of hybrid designs are discussed, including combinations of case-control, case-crossover, and cohort designs.
Usability Testing with Online Research Panels: A Case Study from the Field of Instructional Design
ERIC Educational Resources Information Center
Williams Van Rooij, Shahron
2013-01-01
One of the challenges experienced by students of instructional design is eliciting user participation when designing and developing products for course or program projects, particularly over multiple cycles of evaluation. Student projects do not normally have budgets to engage recruitment companies or provide participant incentives. This paper…
Precision of Curriculum-Based Measurement Reading Data: Considerations for Multiple-Baseline Designs
ERIC Educational Resources Information Center
Klingbeil, David A.; Van Norman, Ethan R.; Nelson, Peter M.
2017-01-01
Single-case designs provide an established technology for evaluating the effects of academic interventions. Researchers interested in studying the long-term effects of reading interventions often use curriculum-based measures of reading (CBM-R) as they possess many of the desirable characteristics for use in a time-series design. The reliability…
Introducing Whole-Systems Design to First-Year Engineering Students with Case Studies
ERIC Educational Resources Information Center
Blizzard, Jackie; Klotz, Leidy; Pradhan, Alok; Dukes, Michael
2012-01-01
Purpose: A whole-systems approach, which seeks to optimize an entire system for multiple benefits, not isolated components for single benefits, is essential to engineering design for radically improved sustainability performance. Based on real-world applications of whole-systems design, the Rocky Mountain Institute (RMI) is developing educational…
ERIC Educational Resources Information Center
Mildenhall, Paula; Hackling, Mark
2012-01-01
This paper reports on the analysis of a study of a professional learning intervention focussing on computational estimation. Using a multiple case study design it was possible to describe the impact of the intervention of students' beliefs and computational estimation performance. The study revealed some noteworthy impacts on computational…
Multiple Information Failure: A Case of Different Investments in Form and Content in Graphic Design
ERIC Educational Resources Information Center
Barnes, Carolyn; Taffe, Simone; Miceli, Lucy
2009-01-01
This paper considers a sequence of failures in the design of information. It focuses on the Safe and Sustainable Indoor Cleaning study (SASI Clean), a 2007 government-funded study into cleaning practices in Australian childcare centers. Empowerment through participation was integral to the study, childcare workers being seen as collaborators in…
Video Modeling for Children and Adolescents with Autism Spectrum Disorder: A Meta-Analysis
ERIC Educational Resources Information Center
Thompson, Teresa Lynn
2014-01-01
The objective of this research was to conduct a meta-analysis to examine existing research studies on video modeling as an effective teaching tool for children and adolescents diagnosed with Autism Spectrum Disorder (ASD). Study eligibility criteria included (a) single case research design using multiple baselines, alternating treatment designs,…
Adaptive graph-based multiple testing procedures
Klinglmueller, Florian; Posch, Martin; Koenig, Franz
2016-01-01
Multiple testing procedures defined by directed, weighted graphs have recently been proposed as an intuitive visual tool for constructing multiple testing strategies that reflect the often complex contextual relations between hypotheses in clinical trials. Many well-known sequentially rejective tests, such as (parallel) gatekeeping tests or hierarchical testing procedures are special cases of the graph based tests. We generalize these graph-based multiple testing procedures to adaptive trial designs with an interim analysis. These designs permit mid-trial design modifications based on unblinded interim data as well as external information, while providing strong family wise error rate control. To maintain the familywise error rate, it is not required to prespecify the adaption rule in detail. Because the adaptive test does not require knowledge of the multivariate distribution of test statistics, it is applicable in a wide range of scenarios including trials with multiple treatment comparisons, endpoints or subgroups, or combinations thereof. Examples of adaptations are dropping of treatment arms, selection of subpopulations, and sample size reassessment. If, in the interim analysis, it is decided to continue the trial as planned, the adaptive test reduces to the originally planned multiple testing procedure. Only if adaptations are actually implemented, an adjusted test needs to be applied. The procedure is illustrated with a case study and its operating characteristics are investigated by simulations. PMID:25319733
Van Durme, Thérèse; Schmitz, Olivier; Cès, Sophie; Anthierens, Sibyl; Maggi, Patrick; Delye, Sam; De Almeida Mello, Johanna; Declercq, Anja; Macq, Jean; Remmen, Roy; Aujoulat, Isabelle
2015-06-18
Case management is a type of intervention expected to improve the quality of care and therefore the quality of life of frail, community-dwelling older people while delaying institutionalisation in nursing homes. However, the heterogeneity, multidimensionality and complexity of these interventions make their evaluation by the means of classical approaches inadequate. Our objective was twofold: (i) to propose a tool allowing for the identification of the key components that explain the success of case management for this population and (ii) to propose a typology based on the results of this tool. The process started with a multiple embedded case study design in order to identify the key components of case management. Based on the results of this first step, data were collected among 22 case management interventions, in order to evaluate their expected effectiveness. Finally, multiple correspondence analyses was conducted to propose a typology of case management. The overall approach was informed by Wagner's Chronic Care Model and the theory of complexity. The study identified a total of 23 interacting key components. Based on the clustering of response patterns of the 22 case management projects included in our study, three types of case management programmes were evidenced, situated on a continuum from a more "socially-oriented" type towards a more "clinically-oriented" type of case management. The type of feedback provided to the general practitioner about both the global geriatric assessment and the result of the intervention turned out to be the most discriminant component between the types. The study design allowed to produce a tool that can be used to distinguish between different types of case management interventions and further evaluate their effect on frail older people in terms of the delaying institutionalisation, functional and cognitive status, quality of life and societal costs.
ERIC Educational Resources Information Center
Lambert, Misty D.; Velez, Jonathan J.; Elliott, Kristopher M.
2014-01-01
This multiple case study was designed to understand the experience of implementing the Curriculum for Agricultural Science Education (CASE) for five teachers at four high schools. All teachers were in their first year of implementing CASE. Through the use of weekly journals, semi-structured interviews and a focus group, researchers attempted to…
ERIC Educational Resources Information Center
Helyer, Ruth; Lee, Dionne
2012-01-01
Purpose: The purpose of this paper is to explore the issues around a multiple generational workforce and more specifically, the challenges and benefits for education providers and employers. Design/methodology/approach: Reviewing research papers, analysing academic texts, interrogating market intelligence and contextualising case studies, the…
Teaching Children with Language-Learning Disabilities to Plan and Revise Compare-Contrast Texts
ERIC Educational Resources Information Center
Shen, Mei; Troia, Gary A.
2018-01-01
This study used a multiple-probe, multiple-baseline single-case design to investigate the efficacy of planning, and then revising strategy instruction using self-regulated strategy development on the compare-contrast writing performance of three late elementary students with language-learning disabilities. After receiving the planning instruction,…
ERIC Educational Resources Information Center
Klinger, Mary A.
2012-01-01
The purpose of this mixed methods study was to determine the effect of professional development on teachers' perceptions of their ability to foster resilience. Secondary questions investigated the effects of school level and socioeconomic status. An exploratory multi-site case study was designed to compare the perceptions of educators from…
NASA Astrophysics Data System (ADS)
van der Kolk, Koos; Hartog, Rob; Beldman, Gerrit; Gruppen, Harry
2013-12-01
Increasingly, mobile applications appear on the market that can support students in chemistry laboratory classes. In a multiple app-supported laboratory, each of these applications covers one use-case. In practice, this leads to situations in which information is scattered over different screens and written materials. Such a multiple app-supported laboratory will become awkward with the growth of the number of applications and use cases. In particular, using and switching between applications is likely to induce extraneous cognitive load that can easily be avoided. The manuscript describes the design of a prototype smartphone web app (LabBuddy) designed to support students in food chemistry laboratory classes. The manuscript describes a case study ( n = 26) of the use of a LabBuddy prototype in such a laboratory class. Based on the evaluation of this case study, design requirements for LabBuddy were articulated. LabBuddy should work on HTML5 capable devices, independent of screen size, by having a responsive layout. In addition, LabBuddy should enable a student using LabBuddy to switch between devices without much effort. Finally, LabBuddy should offer an integrated representation of information.
ERIC Educational Resources Information Center
Boshuizen, Henny P. A.; Bongaerts, Maureen Machiels; van de Wiel, Margaretha W. J.; Schmidt, Henk G.
The effects of experience with a series of similar cases on the knowledge restructuring and learning from text were studied in a longitudinal design. Two groups of fourth-year medical students were confronted with a series of cases, part of them having the same underlying disease. The cases were interspersed with fillers, and each set of cases had…
Ploeg, Jenny; Denton, Margaret; Hutchison, Brian; McAiney, Carrie; Moore, Ainsley; Brazil, Kevin; Tindale, Joseph; Lam, Annie
2017-01-01
Abstract Objective To understand how family physicians facilitate older patients’ access to community support services (CSSs) and to identify similarities and differences across primary health care (PHC) models. Design Qualitative, multiple-case study design using semistructured interviews. Setting Four models of PHC delivery, specifically 2 family health teams (FHTs), 4 non-FHTs family health organizations, 4 fee-for-service practices, and 2 community health centres in urban Ontario. Participants Purposeful sampling of 23 family physicians in solo and small and large group practices within the 4 models of PHC. Methods A multiple-case study approach was used. Semistructured interviews were conducted and data were analyzed using within- and cross-case analysis. Case study tactics to ensure study rigour included memos and an audit trail, investigator triangulation, and the use of multiple, rather than single, case studies. Main findings Three main themes were identified: consulting and communicating with the health care team to create linkages; linking patients and families to CSSs; and relying on out-of-date resources and ineffective search strategies for information on CSSs. All participants worked with their team members; however, those in FHTs and community health centres generally had a broader range of health care providers available to assist them. Physicians relied on home-care case managers to help make linkages to CSSs. Physicians recommended the development of an easily searchable, online database containing available CSSs. Conclusion This study shows the importance of interprofessional teamwork in primary care settings to facilitate linkages of older patients to CSSs. The study also provides insight into the strategies physicians use to link older persons to CSSs and their recommendations for change. This understanding can be used to develop resources and approaches to better support physicians in making appropriate linkages to CSSs. PMID:28115458
Project-Based Social Justice Mathematics: A Case Study of Five 6th Grade Students
ERIC Educational Resources Information Center
McHugh, Maighread L.
2015-01-01
The purpose of this qualitative multiple case study was to explore how five sixth grade female students navigated the process of project-based learning as they designed and implemented their own project centered on mathematics while using a social justice lens. The theoretical frameworks of Authentic Intellectual Work and Social Justice…
Real life juvenile toxicity case studies: the good, the bad and the ugly.
De Schaepdrijver, Luc; Rouan, Marie-Claude; Raoof, Araz; Bailey, Graham P; De Zwart, Loeckie; Monbaliu, Johan; Coogan, Timothy P; Lammens, Lieve; Coussement, Werner
2008-09-01
With the growing experience in the conduct of juvenile toxicity studies for multiple classes of compound, the 'case-by-case' approach has become under much more pressure. Instead, a general screen or 'standard design' is now commonly expected by regulatory authorities with more routine inclusion of neurological and reproductive assessments. Minor modifications or additions can be made to the design to address specific questions according to the class of drug or intended clinical use. This drift from a 'case-by-case' approach to a 'standard design' approach is present within certain reviewing divisions of the FDA, often requesting by default a rodent and non-rodent juvenile animal study. However, juvenile animal studies should be designed thoughtfully to fulfil a purpose based on scientific rationale, with each endpoint carefully considered in terms of practicality and interpretability of data generated. Only when using the appropriate strategy and design may juvenile studies add value by (1) identifying potential safety or pharmacokinetic issues for drugs intended for paediatric use, (2) suggesting additional clinical endpoints and (3) adding new information to the product label. As the knowledge from juvenile animal studies in various species grows, a better understanding of the significance/relevance of findings will be achieved.
Including Multiple Voices in Collaboratively Designing a Teacher Education Program
ERIC Educational Resources Information Center
Konecki, Loretta R.; Sturdivant, Robika L.; King, Caryn M.; Melin, Jacquelyn A.; Lancaster, Paula E.
2012-01-01
This narrative case study describes the collaborative processes employed by a midwestern university as it designed and implemented a clinically based, postbaccalaureate teacher preparation program for science, technology, engineering, and mathematics (STEM) graduates committed to teaching in high need secondary schools. The program development…
The Multiple Roles of the Task Design Mediator in Telecollaboration
ERIC Educational Resources Information Center
Fuchs, Carolin; Snyder, Bill; Tung, Bruce; Jung Han, Yu
2017-01-01
This case study explores how a Chinese-American novice teacher acted as mediator in a telecollaboration with student teacher (ST) peers in the USA who designed tasks for his English as a foreign language (EFL) learners in China. The novice teacher was instrumental in mediating the student teachers' task design process by providing feedback…
ERIC Educational Resources Information Center
Kelting, Scott
2011-01-01
This research is a retrospective case study designed to document and analyze the process of decision-making by educational leaders and stakeholders at a four-year university. For this study, educational leaders and key stakeholders agreed to extensive interviews about the decisions made during the design, construction, and post-occupancy phases of…
ERIC Educational Resources Information Center
Newcomer, Laurie J.
2010-01-01
It is essential to provide high quality interventions designed to improve struggling readers' reading comprehension while making use of limited resources. This study explored, through an holistic, multiple-case study design, volunteer-student interactions and activities in an after school reading program utilizing minimally-trained volunteers. The…
Music therapy in the treatment of multiple sclerosis: a comprehensive literature review.
Ostermann, Thomas; Schmid, Wolfgang
2006-04-01
Coping with multiple sclerosis symptoms still remains a challenge for each patient suffering from this chronic inflammatory disease. Therefore, patients often turn to using complementary and alternative medicine (CAM). In this review, the authors aimed to investigate the current state of literature of music therapy in the treatment of multiple sclerosis (MS). Medline, PubMed, Embase, AMED, CAMbase and the Music Therapy World Journal Index were searched for the terms MS and 'music therapy'. In addition, an internet search using Google Scholar was performed. The authors found seven case-reports/series and seven studies on music therapy for MS-patients. Both the case reports and studies presented here are pioneer work. Most of the studies are naturally predominated by the use of qualitative and uncontrolled research designs. Nevertheless, the results of the studies as well as the case reports demonstrate patients' improvement in the domains of self-acceptance, anxiety and depression. The results of the studies as well as the case reports define a sufficient basis for further music therapeutical work as they show a variety of psychosocial and emotional benefits for MS patients.
Universal Design for Learning and School Libraries: A Logical Partnership
ERIC Educational Resources Information Center
Robinson, David E.
2017-01-01
This article will explore the basic tenets of Universal Design for Learning (UDL) in relation to collaborative curriculum development and implementation; provide a case study examination of UDL principles in action; and suggest school library curricular activities that provide opportunities for multiple means of representation, action, and…
ERIC Educational Resources Information Center
Harney, Kristin
2014-01-01
The primary purpose of this short-term study was to examine pre-service classroom teachers' intentions to integrate music in their future classrooms. Using the theory of planned behavior (Fishbein & Ajzen, 2010) as a framework, and embedded, multiple-case study design, I developed case studies of six pre-service classroom teachers enrolled in…
ERIC Educational Resources Information Center
Van Praag, Benjamin; Sanchez, Hugo Santiago
2015-01-01
Adopting a multiple-case, multiple-method design, this study investigates mobile technology use in the practices of three experienced second language teachers. The findings, based on an analysis of the teachers' rationales, stated beliefs and classroom actions, show that the teachers tend to prohibit or reluctantly tolerate mobile device usage,…
Methodology Series Module 2: Case-control Studies.
Setia, Maninder Singh
2016-01-01
Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.
Nature and Role of Traditional Forms of Counselling in Zambia: A Case of Lusaka Province
ERIC Educational Resources Information Center
Chiboola, Hector; Munsaka, Sody M.
2018-01-01
The aim of this study was to determine the nature and role of traditional forms of counselling and the scope of common problems presented to traditional counsellors in Lusaka province. It used a qualitative research methodology and deployed a holistic single-case study design with multiple embedded units of analysis. The sample consisted of 80…
ERIC Educational Resources Information Center
Ranker, Jason
2007-01-01
This case study closely examines how John (a former student of mine, age eight, second grade) composed during an informal writing group at school. Using qualitative research methods, I found that John selectively took up conventions, characters, story grammars, themes, and motifs from video games, television, Web pages, and comics. Likening his…
ERIC Educational Resources Information Center
Velastegui, Pamela J.
2013-01-01
This hypothesis-generating case study investigates the naturally emerging roles of technology brokers and technology leaders in three independent schools in New York involving 92 school educators. A multiple and mixed method design utilizing Social Network Analysis (SNA) and fuzzy set Qualitative Comparative Analysis (FSQCA) involved gathering…
ERIC Educational Resources Information Center
Karayama, Saffet
2018-01-01
The aim of the study was to determine what ethical dilemmas are faced by school administrators working in different institutions, what they are doing to solve the dilemmas/according to the motives. The research is a patterned qualitative case study and multiple case design is used. 50 school administrators participated by easy-to-reach state…
Baird, Joanne M.; Kim, Young Joo; Rajora, Kuwar B.; D’Silva, Delma; Podolinsky, Lin; Mazefsky, Carla; Minshew, Nancy
2014-01-01
We examined whether different doses of therapeutic riding influenced parent-nominated target behaviors of children with autism spectrum disorder (ASD) (a) during the session (b) at home, and (c) in the community. We used a single subject multiple Baseline, multiple case design, with dosing of 1, 3, and 5 times/week. Three boys with ASD, 6–8 years of age participated, and counts of target behaviors were collected in each setting and phase of the study. Compared to Baseline, 70 % of the target behaviors were better during Intervention and improvement was retained in 63 % of the behaviors during Withdrawal. Increased doses of therapeutic riding were significant for magnitude of change, and the effect of the therapeutic riding sessions generalized to home and community. PMID:24091469
Statistical innovations in diagnostic device evaluation.
Yu, Tinghui; Li, Qin; Gray, Gerry; Yue, Lilly Q
2016-01-01
Due to rapid technological development, innovations in diagnostic devices are proceeding at an extremely fast pace. Accordingly, the needs for adopting innovative statistical methods have emerged in the evaluation of diagnostic devices. Statisticians in the Center for Devices and Radiological Health at the Food and Drug Administration have provided leadership in implementing statistical innovations. The innovations discussed in this article include: the adoption of bootstrap and Jackknife methods, the implementation of appropriate multiple reader multiple case study design, the application of robustness analyses for missing data, and the development of study designs and data analyses for companion diagnostics.
ERIC Educational Resources Information Center
Armstrong, Ann W.
2008-01-01
The purpose of this study was to gain an understanding of what e-Learning executives believe are the critical success factors for companies to successfully deliver training and education over the world-wide web. The study was a qualitative, multiple-case study design including in-depth, semi-structured interviews that incorporated verbal critical…
Use of Comparative Case Study Methodology for US Public Health Policy Analysis: A Review.
Dinour, Lauren M; Kwan, Amy; Freudenberg, Nicholas
There is growing recognition that policies influence population health, highlighting the need for evidence to inform future policy development and reform. This review describes how comparative case study methodology has been applied to public health policy research and discusses the methodology's potential to contribute to this evidence. English-language, peer-reviewed articles published between 1995 and 2012 were sought from 4 databases. Articles were included if they described comparative case studies addressing US public health policy. Two researchers independently assessed the 20 articles meeting review criteria. Case-related characteristics and research design tactics utilized to minimize threats to reliability and validity, such as the use of multiple sources of evidence and a case study protocol, were extracted from each article. Although comparative case study methodology has been used to analyze a range of public health policies at all stages and levels, articles reported an average use of only 3.65 (out of 10) research design tactics. By expanding the use of accepted research design tactics, public health policy researchers can contribute to expanding the evidence needed to advance health-promoting policies.
ERIC Educational Resources Information Center
Tracey, Monica W.; Unger, Kelly L.
2012-01-01
As the need for instructing a globalized workforce increases, instructional designers must embrace the constraints and the opportunities these projects provide in order to move the field of cross-cultural instructional design (ID) forward. Cross-cultural projects offer multiple avenues for growth in ID practice, overcoming cultural barriers, and a…
Instructional Leadership of High School Assistant Principals in Northern California
ERIC Educational Resources Information Center
Garrard, John Christian Timothy
2013-01-01
To identify how high school assistant principals in large suburban schools serve as instructional leaders and how they develop these skills, this research utilized a multiple-case study design, followed by a cross-case analysis of the data. This research explores the instructional leadership of three female comprehensive high school assistant…
ERIC Educational Resources Information Center
Olson, Joanne K.; Bruxvoort, Crystal N.; Vande Haar, Andrea J.
2016-01-01
Little is known about how the content of a video case influences what preservice teachers learn about science teaching. This study was designed to determine the impact of two different video cases on preservice elementary teachers' conceptions of multiple aspects of effective science teaching, with one video selected to focus attention on the role…
Sustaining Online Teacher Professional Development through Community Design
ERIC Educational Resources Information Center
Henderson, Michael
2007-01-01
Purpose: The purpose of this paper is to explore the role of community of practice in sustaining teachers' participation in a blended (face-to-face and online) professional development course. Design/methodology/approach: A longitudinal multiple-case study methodology was used in researching groups of five teachers in Australia and four teachers…
Garla, Bharath Kumar; Deshmukh, Seema; Murthy, Prashanth Sadashiva; Satish, G
2015-01-01
Traumatic injuries to the dento-alveolar structures are emergencies that compromise the quality of life of the patients. In addition to symptomatic management, definitive functional restoration and suitable rehabilitation becomes a major treatment objective in such cases. The dynamics of the traumatic forces may cause multiple injuries of different grades to the oral and para-oral structures, which makes comprehensive management a greater challenge to the dentist. The present case report elaborates a modified esthetic splint designed to treat multiple dental injuries in children, which can promote healing, restore optimal functionality along with esthetic rehabilitation to psychologically benefit the child during the time of recovery. PMID:26435631
ERIC Educational Resources Information Center
Nasir, Ambareen; Heineke, Amy J.
2014-01-01
This study investigates how early clinical experiences impact teacher candidates' learning and experiences with Latina/o English learners in a field-based program housed in a multilingual, urban elementary school. We draw on multiple-case study design and use discourse analysis to explore cases of three candidates. Findings reveal exploration of…
Design, methodological issues and participation in a multiple sclerosis case-control study.
Williamson, D M; Marrie, R A; Ashley-Koch, A; Schiffer, R; Trottier, J; Wagner, L
2012-09-01
This study was conducted to determine whether the risk of developing multiple sclerosis (MS) was associated with certain environmental exposures or genetic factors previously reported to influence MS risk. This paper describes the methodological issues, study design and characteristics of the study population. Individuals with definite MS were identified from a prevalence study conducted in three geographic areas. The target number of cases was not reached, so an additional study area was added. Identifying clinic controls was inefficient, so controls were recruited using random digit dialing. All study participants completed a detailed questionnaire regarding environmental exposures using computer-assisted telephone interviewing, and blood was collected for genetic analysis. In total, 276 cases and 590 controls participated, but participation rates were low, ranging from 28.4% to 38.9%. Only one-third (33.6%) of individuals identified in the prevalence study agreed to participate in the case-control study. Cases were more likely to be non-Hispanic white and older than their source populations as identified in the preceding prevalence study (P < 0.05). Most participants provided a blood sample for genotyping (91%; n = 789). Epidemiological studies play a key role in identifying genetic and environmental factors that are associated with complex diseases like MS. Methodological issues arise in every study, and investigators need to be able to detect, respond to and correct problems in a timely and scientifically valid manner. © 2011 John Wiley & Sons A/S.
ERIC Educational Resources Information Center
Kramer, Betty J.; Auer, Casey
2005-01-01
Purpose: This study explored the challenges in providing end-of-life care to low-income elders with multiple comorbid chronic conditions in a fully "integrated" managed care program, and it highlighted essential recommendations. Design and Methods: A case-study design was used that involved an extensive analysis of qualitative data from five focus…
The Design of Secondary Schools--A Case Study, Singapore.
ERIC Educational Resources Information Center
Liew Kok-Pun, Michael; And Others
Land scarcity dominates the thinking of school planners in Singapore. Techniques for optimizing the use of land for schools include (1) the construction of multi-storied or high-rise schools; (2) operation of a double-shift system and, in some cases, a triple-shift system; (3) multiple use of educational spaces; and (4) construction of several…
Leading for Instructional Improvement in the Context of Accountability: Central Office Leadership
ERIC Educational Resources Information Center
Rigby, Jessica Goodman; Corriell, Rebecca; Kuhl, Katie J.
2018-01-01
This case was written to help prepare central office leaders who are expected to design systems and lead toward instructional improvement in the context of both educational accountability and implementation of standards with increased rigor. The intent of this case study is to encourage educators to examine the complex and multiple challenges of…
Methodology Series Module 2: Case-control Studies
Setia, Maninder Singh
2016-01-01
Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same ‘study base’ as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive – particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases – selection bias and recall bias. PMID:27057012
NASA Astrophysics Data System (ADS)
McDermott, Mark Andrew
2009-12-01
This study was designed to examine the impact of embedding multiple modes of representing science information on student conceptual understanding in science. Multiple representations refer to utilizing charts, graphs, diagrams, and other types of representations to communicate scientific information. This study investigated the impact of encouraging students to embed or integrate the multiple modes with text in end of unit writing-to-learn activities. A quasi-experimental design with four separate sites consisting of intact chemistry classes taught by different teachers at each site was utilized. At each site, approximately half of the classes were designated treatment classes and students in these classes participated in activities designed to encourage strategies to embed multiple modes within text in student writing. The control classes did not participate in these activities. All classes participated in identical end of unit writing tasks in which they were required to use at least one mode other than text, followed by identical end of unit assessments. This progression was then repeated for a second consecutive unit of study. Analysis of quantitative data indicated that in several cases, treatment classes significantly outperformed control classes both on measures of embeddedness in writing and on end of unit assessment measures. In addition, analysis at the level of individual students indicated significant positive correlations in many cases between measures of student embeddedness in writing and student performance on end of unit assessments. Three factors emerged as critical in increasing the likelihood of benefit for students from these types of activities. First, the level of teacher implementation and emphasis on the embeddedness lessons was linked to the possibility of conceptual benefit. Secondly, students participating in two consecutive lessons appeared to receive greater benefit during the second unit, inferring a cumulative benefit. Finally, differential impact of the degree of embeddedness on student performance was noted based on student's level of science ability prior to the initiation of study procedures.
How to Construct a Mixed Methods Research Design.
Schoonenboom, Judith; Johnson, R Burke
2017-01-01
This article provides researchers with knowledge of how to design a high quality mixed methods research study. To design a mixed study, researchers must understand and carefully consider each of the dimensions of mixed methods design, and always keep an eye on the issue of validity. We explain the seven major design dimensions: purpose, theoretical drive, timing (simultaneity and dependency), point of integration, typological versus interactive design approaches, planned versus emergent design, and design complexity. There also are multiple secondary dimensions that need to be considered during the design process. We explain ten secondary dimensions of design to be considered for each research study. We also provide two case studies showing how the mixed designs were constructed.
ERIC Educational Resources Information Center
Datchuk, Shawn M.
2016-01-01
The present study investigated the effects of a multicomponent intervention on the writing behavior of adolescents with writing difficulties. A single-case design consisting of a combination of multiple-probe design across participants and pre-post test was used. Four participants completed two intervention phases: (a) sentence instruction and…
A Meta-Analysis of the Taped Problems Intervention
ERIC Educational Resources Information Center
Kleinert, Whitney L.; Codding, Robin S.; Minami, Takuya; Gould, Kaitlin
2018-01-01
Taped problems is an intervention strategy for addressing mathematics fluency that has been evaluated in multiple single-case design studies. Although its efficacy has been supported in individual studies, no comprehensive quantitative synthesis has been conducted on taped problems. The purpose of this study was to synthesize the literature that…
L2 Learners' Informal Online Interactions in Social Network Communities
ERIC Educational Resources Information Center
Malerba, Maria-Luisa
2012-01-01
This paper reports on a study on the use of social network sites (SNSs) designed for L2 learning, such as "Livemocha" and "Busuu", where learners autonomously seek opportunities for authentic interaction in spontaneous ways. The study consists in a longitudinal multiple case study approach to investigate learners' informal…
Brain MRI volumetry in a single patient with mild traumatic brain injury.
Ross, David E; Castelvecchi, Cody; Ochs, Alfred L
2013-01-01
This letter to the editor describes the case of a 42 year old man with mild traumatic brain injury and multiple neuropsychiatric symptoms which persisted for a few years after the injury. Initial CT scans and MRI scans of the brain showed no signs of atrophy. Brain volume was measured using NeuroQuant®, an FDA-approved, commercially available software method. Volumetric cross-sectional (one point in time) analysis also showed no atrophy. However, volumetric longitudinal (two points in time) analysis showed progressive atrophy in several brain regions. This case illustrated in a single patient the principle discovered in multiple previous group studies, namely that the longitudinal design is more powerful than the cross-sectional design for finding atrophy in patients with traumatic brain injury.
Jäger, Frederik; Riemer, Martin; Abendroth, Martin; Sehner, Susanne; Harendza, Sigrid
2014-07-08
Virtual patient (VP) cases are an effective teaching method, although little is known about how to design and implement them for maximum effectiveness. The aim of this study was to explore the effect of case design and teamwork on students' learning outcome. One hundred forty-six undergraduate medical students participated in a mandatory medical computer science course consisting of five seminars. At the end of each seminar, they worked on one VP case, either in teams of two or individually. Each student filled out an introductory and a final survey and a feedback sheet after completing each case. Additionally, there was a surprise multiple choice (MC) test after the last seminar with three questions regarding each case. Students with more clinical experience and students who had worked in a team performed significantly better on MC questions. Students with less clinical experience more frequently used information which had been positioned less prominently on the case material. Certain aspects of case design were rated more positively by students who had an interest in e-learning. In general, students preferred to work on cases for less than 15 minutes. Clinically more advanced students and students working with a partner seem to benefit most from short VP cases with prominently presented information.
Qualitative case study data analysis: an example from practice.
Houghton, Catherine; Murphy, Kathy; Shaw, David; Casey, Dympna
2015-05-01
To illustrate an approach to data analysis in qualitative case study methodology. There is often little detail in case study research about how data were analysed. However, it is important that comprehensive analysis procedures are used because there are often large sets of data from multiple sources of evidence. Furthermore, the ability to describe in detail how the analysis was conducted ensures rigour in reporting qualitative research. The research example used is a multiple case study that explored the role of the clinical skills laboratory in preparing students for the real world of practice. Data analysis was conducted using a framework guided by the four stages of analysis outlined by Morse ( 1994 ): comprehending, synthesising, theorising and recontextualising. The specific strategies for analysis in these stages centred on the work of Miles and Huberman ( 1994 ), which has been successfully used in case study research. The data were managed using NVivo software. Literature examining qualitative data analysis was reviewed and strategies illustrated by the case study example provided. Discussion Each stage of the analysis framework is described with illustration from the research example for the purpose of highlighting the benefits of a systematic approach to handling large data sets from multiple sources. By providing an example of how each stage of the analysis was conducted, it is hoped that researchers will be able to consider the benefits of such an approach to their own case study analysis. This paper illustrates specific strategies that can be employed when conducting data analysis in case study research and other qualitative research designs.
Systematic procedure for designing processes with multiple environmental objectives.
Kim, Ki-Joo; Smith, Raymond L
2005-04-01
Evaluation of multiple objectives is very important in designing environmentally benign processes. It requires a systematic procedure for solving multiobjective decision-making problems due to the complex nature of the problems, the need for complex assessments, and the complicated analysis of multidimensional results. In this paper, a novel systematic procedure is presented for designing processes with multiple environmental objectives. This procedure has four steps: initialization, screening, evaluation, and visualization. The first two steps are used for systematic problem formulation based on mass and energy estimation and order of magnitude analysis. In the third step, an efficient parallel multiobjective steady-state genetic algorithm is applied to design environmentally benign and economically viable processes and to provide more accurate and uniform Pareto optimal solutions. In the last step a new visualization technique for illustrating multiple objectives and their design parameters on the same diagram is developed. Through these integrated steps the decision-maker can easily determine design alternatives with respect to his or her preferences. Most importantly, this technique is independent of the number of objectives and design parameters. As a case study, acetic acid recovery from aqueous waste mixtures is investigated by minimizing eight potential environmental impacts and maximizing total profit. After applying the systematic procedure, the most preferred design alternatives and their design parameters are easily identified.
Deloria Knoll, Maria; Fu, Wei; Shi, Qiyuan; Prosperi, Christine; Wu, Zhenke; Hammitt, Laura L; Feikin, Daniel R; Baggett, Henry C; Howie, Stephen R C; Scott, J Anthony G; Murdoch, David R; Madhi, Shabir A; Thea, Donald M; Brooks, W Abdullah; Kotloff, Karen L; Li, Mengying; Park, Daniel E; Lin, Wenyi; Levine, Orin S; O'Brien, Katherine L; Zeger, Scott L
2017-06-15
In pneumonia, specimens are rarely obtained directly from the infection site, the lung, so the pathogen causing infection is determined indirectly from multiple tests on peripheral clinical specimens, which may have imperfect and uncertain sensitivity and specificity, so inference about the cause is complex. Analytic approaches have included expert review of case-only results, case-control logistic regression, latent class analysis, and attributable fraction, but each has serious limitations and none naturally integrate multiple test results. The Pneumonia Etiology Research for Child Health (PERCH) study required an analytic solution appropriate for a case-control design that could incorporate evidence from multiple specimens from cases and controls and that accounted for measurement error. We describe a Bayesian integrated approach we developed that combined and extended elements of attributable fraction and latent class analyses to meet some of these challenges and illustrate the advantage it confers regarding the challenges identified for other methods. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
Informatics tools to improve clinical research study implementation.
Brandt, Cynthia A; Argraves, Stephanie; Money, Roy; Ananth, Gowri; Trocky, Nina M; Nadkarni, Prakash M
2006-04-01
There are numerous potential sources of problems when performing complex clinical research trials. These issues are compounded when studies are multi-site and multiple personnel from different sites are responsible for varying actions from case report form design to primary data collection and data entry. We describe an approach that emphasizes the use of a variety of informatics tools that can facilitate study coordination, training, data checks and early identification and correction of faulty procedures and data problems. The paper focuses on informatics tools that can help in case report form design, procedures and training and data management. Informatics tools can be used to facilitate study coordination and implementation of clinical research trials.
A Multiple Case Study of College-Contextualized Mathematics Curriculum
ERIC Educational Resources Information Center
Valenzuela, Hector
2018-01-01
Contextualization is a method used for mathematics curriculum design within lesson plans and as a pedagogical practice in face-to-face classes. Many researchers are studying the effects of using contextualization in the teaching and the learning process for mathematics (Bottge & Cho, 2013; Perin, 2011; Young, Hodge, Edwards, & Leising,…
Family SMEs in Ireland as Learning Organizations
ERIC Educational Resources Information Center
Birdthistle, Naomi
2008-01-01
Purpose: The purpose of this paper is to investigate whether small and medium-sized family businesses in Ireland have the potential to be classified as learning organizations. Design/methodology/approach: The research methodology adopted for this study is that of multiple-case studies. In this research, personal interviews were selected as the…
Merlé, Y; Mentré, F
1995-02-01
In this paper 3 criteria to design experiments for Bayesian estimation of the parameters of nonlinear models with respect to their parameters, when a prior distribution is available, are presented: the determinant of the Bayesian information matrix, the determinant of the pre-posterior covariance matrix, and the expected information provided by an experiment. A procedure to simplify the computation of these criteria is proposed in the case of continuous prior distributions and is compared with the criterion obtained from a linearization of the model about the mean of the prior distribution for the parameters. This procedure is applied to two models commonly encountered in the area of pharmacokinetics and pharmacodynamics: the one-compartment open model with bolus intravenous single-dose injection and the Emax model. They both involve two parameters. Additive as well as multiplicative gaussian measurement errors are considered with normal prior distributions. Various combinations of the variances of the prior distribution and of the measurement error are studied. Our attention is restricted to designs with limited numbers of measurements (1 or 2 measurements). This situation often occurs in practice when Bayesian estimation is performed. The optimal Bayesian designs that result vary with the variances of the parameter distribution and with the measurement error. The two-point optimal designs sometimes differ from the D-optimal designs for the mean of the prior distribution and may consist of replicating measurements. For the studied cases, the determinant of the Bayesian information matrix and its linearized form lead to the same optimal designs. In some cases, the pre-posterior covariance matrix can be far from its lower bound, namely, the inverse of the Bayesian information matrix, especially for the Emax model and a multiplicative measurement error. The expected information provided by the experiment and the determinant of the pre-posterior covariance matrix generally lead to the same designs except for the Emax model and the multiplicative measurement error. Results show that these criteria can be easily computed and that they could be incorporated in modules for designing experiments.
Experimental comparison of conventional and nonlinear model-based control of a mixing tank
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haeggblom, K.E.
1993-11-01
In this case study concerning control of a laboratory-scale mixing tank, conventional multiloop single-input single-output (SISO) control is compared with model-based'' control where the nonlinearity and multivariable characteristics of the process are explicitly taken into account. It is shown, especially if the operating range of the process is large, that the two outputs (level and temperature) cannot be adequately controlled by multiloop SISO control even if gain scheduling is used. By nonlinear multiple-input multiple-output (MIMO) control, on the other hand, very good control performance is obtained. The basic approach to nonlinear control used in this study is first to transformmore » the process into a globally linear and decoupled system, and then to design controllers for this system. Because of the properties of the resulting MIMO system, the controller design is very easy. Two nonlinear control system designs based on a steady-state and a dynamic model, respectively, are considered. In the dynamic case, both setpoint tracking and disturbance rejection can be addressed separately.« less
A Pilot Study of Integrated Listening Systems for Children with Sensory Processing Problems
ERIC Educational Resources Information Center
Schoen, Sarah A.; Miller, Lucy J.; Sullivan, Jillian
2015-01-01
This pilot study explored the effects of Integrated Listening Systems (iLs) Focus Series on individualized parent goals for children with sensory processing impairments. A nonconcurrent multiple baseline, repeated measure across participants, single-case study design was employed (n = 7). The 40-session intervention was delivered at home and in…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-15
... medical device for its intended use. Evidence from one or more pivotal clinical studies generally serves... some cases, a PMA may include multiple studies designed to answer different scientific questions. The... studies intended to support premarket submissions for medical devices and for FDA staff who review those...
Improving the Process of Career Decision Making: An Action Research Approach
ERIC Educational Resources Information Center
Greenbank, Paul
2011-01-01
Purpose: This study adopts an action research approach with the aim of improving the process of career decision making among undergraduates in a business school at a "new" university in the UK. Design/methodology/approach: The study utilised unfreezing techniques, multiple case studies in conjunction with the principle of analogical…
ERIC Educational Resources Information Center
Bahcivan, Eralp; Cobern, William W.
2016-01-01
This study investigated comprehensive science teaching belief systems and their relation to science teachers' pedagogical content knowledge and teaching practices. Rokeach's (1968) belief system was used as a framework for representing the hierarchy among in-service teachers' teaching beliefs. This study employed a multiple case study design with…
[The choice of the type of design in the clinical investigation studies. Case and control studies].
Posada de la Paz, M
2004-09-01
Case-control studies are appropriate designs in neurology sciences to search for risk factors that have already occurred in a group of patients. In them, the subjects are selected on the basis of whether they have the disease or not and then they are compared in regards to the risk factor or prognosis investigated. These sorts of designs can be performed in a shorter and cheaper way than the regular cohort studies. They are appropriate for the evaluation of rare diseases and can examine multiple etiological factors for a single disease. On the contrary, they are not so efficient when rare exposures are involved. Incidence rates in exposed and non-exposed subjects cannot be calculated and on some occasions, the timing between exposure and outcome can be very difficult to establish. The Odds Ratio and its confident intervals is the measurement used for estimating the risk strength in this design. The clinical neurologist should be familiar with these terms, given the frequency of case-control studies described in neurology science literature, and should know their principal advantages and limitations.
Hitchcock, Elaine R.; Ferron, John
2017-01-01
Purpose Single-case experimental designs are widely used to study interventions for communication disorders. Traditionally, single-case experiments follow a response-guided approach, where design decisions during the study are based on participants' observed patterns of behavior. However, this approach has been criticized for its high rate of Type I error. In masked visual analysis (MVA), response-guided decisions are made by a researcher who is blinded to participants' identities and treatment assignments. MVA also makes it possible to conduct a hypothesis test assessing the significance of treatment effects. Method This tutorial describes the principles of MVA, including both how experiments can be set up and how results can be used for hypothesis testing. We then report a case study showing how MVA was deployed in a multiple-baseline across-subjects study investigating treatment for residual errors affecting rhotics. Strengths and weaknesses of MVA are discussed. Conclusions Given their important role in the evidence base that informs clinical decision making, it is critical for single-case experimental studies to be conducted in a way that allows researchers to draw valid inferences. As a method that can increase the rigor of single-case studies while preserving the benefits of a response-guided approach, MVA warrants expanded attention from researchers in communication disorders. PMID:28595354
Byun, Tara McAllister; Hitchcock, Elaine R; Ferron, John
2017-06-10
Single-case experimental designs are widely used to study interventions for communication disorders. Traditionally, single-case experiments follow a response-guided approach, where design decisions during the study are based on participants' observed patterns of behavior. However, this approach has been criticized for its high rate of Type I error. In masked visual analysis (MVA), response-guided decisions are made by a researcher who is blinded to participants' identities and treatment assignments. MVA also makes it possible to conduct a hypothesis test assessing the significance of treatment effects. This tutorial describes the principles of MVA, including both how experiments can be set up and how results can be used for hypothesis testing. We then report a case study showing how MVA was deployed in a multiple-baseline across-subjects study investigating treatment for residual errors affecting rhotics. Strengths and weaknesses of MVA are discussed. Given their important role in the evidence base that informs clinical decision making, it is critical for single-case experimental studies to be conducted in a way that allows researchers to draw valid inferences. As a method that can increase the rigor of single-case studies while preserving the benefits of a response-guided approach, MVA warrants expanded attention from researchers in communication disorders.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piepel, Greg F.; Cooley, Scott K.; Vienna, John D.
This article presents a case study of developing an experimental design for a constrained mixture experiment when the experimental region is defined by single-component constraints (SCCs), linear multiple-component constraints (MCCs), and a nonlinear MCC. Traditional methods and software for designing constrained mixture experiments with SCCs and linear MCCs are not directly applicable because of the nonlinear MCC. A modification of existing methodology to account for the nonlinear MCC was developed and is described in this article. The case study involves a 15-component nuclear waste glass example in which SO3 is one of the components. SO3 has a solubility limit inmore » glass that depends on the composition of the balance of the glass. A goal was to design the experiment so that SO3 would not exceed its predicted solubility limit for any of the experimental glasses. The SO3 solubility limit had previously been modeled by a partial quadratic mixture (PQM) model expressed in the relative proportions of the 14 other components. The PQM model was used to construct a nonlinear MCC in terms of all 15 components. In addition, there were SCCs and linear MCCs. This article discusses the waste glass example and how a layered design was generated to (i) account for the SCCs, linear MCCs, and nonlinear MCC and (ii) meet the goals of the study.« less
Xu, Stanley; Clarke, Christina L; Newcomer, Sophia R; Daley, Matthew F; Glanz, Jason M
2018-05-16
Vaccine safety studies are often electronic health record (EHR)-based observational studies. These studies often face significant methodological challenges, including confounding and misclassification of adverse event. Vaccine safety researchers use self-controlled case series (SCCS) study design to handle confounding effect and employ medical chart review to ascertain cases that are identified using EHR data. However, for common adverse events, limited resources often make it impossible to adjudicate all adverse events observed in electronic data. In this paper, we considered four approaches for analyzing SCCS data with confirmation rates estimated from an internal validation sample: (1) observed cases, (2) confirmed cases only, (3) known confirmation rate, and (4) multiple imputation (MI). We conducted a simulation study to evaluate these four approaches using type I error rates, percent bias, and empirical power. Our simulation results suggest that when misclassification of adverse events is present, approaches such as observed cases, confirmed case only, and known confirmation rate may inflate the type I error, yield biased point estimates, and affect statistical power. The multiple imputation approach considers the uncertainty of estimated confirmation rates from an internal validation sample, yields a proper type I error rate, largely unbiased point estimate, proper variance estimate, and statistical power. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
2014-01-01
Background Virtual patient (VP) cases are an effective teaching method, although little is known about how to design and implement them for maximum effectiveness. The aim of this study was to explore the effect of case design and teamwork on students’ learning outcome. Methods One hundred forty-six undergraduate medical students participated in a mandatory medical computer science course consisting of five seminars. At the end of each seminar, they worked on one VP case, either in teams of two or individually. Each student filled out an introductory and a final survey and a feedback sheet after completing each case. Additionally, there was a surprise multiple choice (MC) test after the last seminar with three questions regarding each case. Results Students with more clinical experience and students who had worked in a team performed significantly better on MC questions. Students with less clinical experience more frequently used information which had been positioned less prominently on the case material. Certain aspects of case design were rated more positively by students who had an interest in e-learning. In general, students preferred to work on cases for less than 15 minutes. Conclusions Clinically more advanced students and students working with a partner seem to benefit most from short VP cases with prominently presented information. PMID:25000965
Smith, Justin D; Handler, Leonard; Nash, Michael R
2010-09-01
The Therapeutic Assessment (TA) model is a relatively new treatment approach that fuses assessment and psychotherapy. The study examines the efficacy of this model with preadolescent boys with oppositional defiant disorder and their families. A replicated single-case time-series design with daily measures is used to assess the effects of TA and to track the process of change as it unfolds. All 3 families benefitted from participation in TA across multiple domains of functioning, but the way in which change unfolded was unique for each family. These findings are substantiated by the Behavior Assessment System for Children (Reynolds & Kamphaus, 2004). The TA model is shown to be an effective treatment for preadolescent boys with oppositional defiant disorder and their families. Further, the time-series design of this study illustrated how this empirically grounded case-based methodology reveals when and how change unfolds during treatment in a way that is usually not possible with other research designs.
Transition to Employment: Role of the Family in Career Development
ERIC Educational Resources Information Center
Lindstrom, Lauren; Doren, Bonnie; Metheny, Jennifer; Johnson, Pam; Zane, Claire
2007-01-01
This study investigated the role of the family in career development and postschool employment outcomes for young adults with learning disabilities. Using a multiple-case study design, the authors examined a set of family structural and process variables. Fifty-nine in-depth interviews were conducted with young adults, parents, and school staff…
ERIC Educational Resources Information Center
Bloxham, Kristy Taylor
2010-01-01
The objective of this study was to examine the use of frequent, anonymous student course surveys as a tool in supporting continuous quality improvement (CQI) principles in online instruction. The study used a qualitative, multiple-case design involving four separate online courses. Analysis methods included pattern matching/explanation building,…
African American Teacher Candidates' Experiences in Teaching Secondary Physical Education
ERIC Educational Resources Information Center
Sato, Takahiro; Hodge, Samuel Russell
2017-01-01
The purpose of this study was to describe and explain the teaching experiences of African American physical education teacher candidates in secondary physical education programs at urban schools. The research design was explanatory multiple-case study situated in positioning theory (Harré & van Langenhove, 1999). The participants were seven…
The Readiness of Schools in Zimbabwe for the Implementation of Early Childhood Education
ERIC Educational Resources Information Center
Mangwaya, Ezron; Blignaut, Sylvan; Pillay, Shervani K.
2016-01-01
This qualitative study focuses on primary schools' state of readiness for the introduction of early childhood education. Adopting a multiple case study design, the article explores, through semi-structured interviews and documentation, school heads, teachers-in-charge and classroom teachers' perceptions of their respective schools' state of…
How Students Navigate the Construction of Heritage Narratives
ERIC Educational Resources Information Center
Levy, Sara Ann
2012-01-01
This qualitative study (n=17) uses a multiple case studies design to interrogate how and why students understand events contained within "heritage histories." By this I mean that the students are too young to have been involved in the events, but that their parents, grandparents, other family members, or other members of an affinity…
Towards an Ecological Understanding of Willingness to Communicate in EFL Classrooms in China
ERIC Educational Resources Information Center
Peng, Jian-E.
2012-01-01
This article reports on a multiple-case study designed to investigate factors influencing willingness to communicate (WTC) in the English as a foreign language (EFL) classroom in China. Four university students participated in this study; data were collected through semi-structured interviews, learning journals recorded by the students, and…
Mathematically Gifted Adolescent Females' Mixed Sentiment toward Gender Stereotypes
ERIC Educational Resources Information Center
Kao, Chen-yao
2015-01-01
There has been a paucity of research on gifted individuals' perceptions of gender stereotypes. The purpose of this study was to explore mathematically gifted adolescent females' perceptions of gender stereotypes through a research design of the qualitative multiple case study involving the constant comparison and the Three C's analysis scheme.…
Teachers' Perceptions of Professional Development in Chilean State-Funded Early Childhood Education
ERIC Educational Resources Information Center
Gómez, Mariel; Ford, Laurie
2017-01-01
This article presents the results of a study on professional development in Chilean state-funded early childhood education. Based on a multiple-case study design and drawing on qualitative methods we explored teachers' perspectives on professional development at two early childhood educational centers. Two centers' directors and four early…
How Students Navigate the Construction of Heritage Narratives
ERIC Educational Resources Information Center
Levy, Sara A.
2017-01-01
Using a multiple case study design, I examine how public high school students (n = 17) make sense of narratives about defining events with which they have specific heritage connections. Focusing on 3 groups of students (Hmong, Chinese, and Jewish) studying 3 heritage events (respectively, the Vietnam War, Modern China, and the Holocaust), this…
Study Abroad as Professional Development: Voices of In-Service Spanish Teachers
ERIC Educational Resources Information Center
Jochum, Christopher J.; Rawlings, Jared R.; Tejada, Ana María
2015-01-01
The purpose of this qualitative inquiry was to understand how four in-service Spanish teachers interpreted their participation in a summer study abroad program and how the experience contributed to their ongoing professional development and language proficiency. Using a multiple case design (Simons, 2009; Stake, 2005; Yin, 2009), the researchers…
Formal Service Practitioners' Views of Family Caregivers' Responsibilities and Difficulties
ERIC Educational Resources Information Center
Guberman, Nancy; Lavoie, Jean-Pierre; Pepin, Jacinthe; Lauzon, Sylvie; Montejo, Maria-Elisa
2006-01-01
This article identifies home care practitioners' perceptions of the responsibilities, difficulties, and needs for support of caregivers. It is based on a study undertaken in Quebec with 55 practitioners and 10 administrators from 10 CLSCs located in rural, urban, and metropolitan areas. The study had a qualitative, multiple-case design and used…
Parent Education for Dialogic Reading: Online and Face-to-Face Delivery Methods
ERIC Educational Resources Information Center
Beschorner, Beth; Hutchison, Amy
2016-01-01
This study explored the impact of a parent education program and the contextual factors that influenced the experiences of families in the program. Seventeen parents completed a 9-week, face-to-face program and 15 parents completed a similar online program. This study was designed as a multiple case study and utilized multimethods for data…
ERIC Educational Resources Information Center
Swift, Ian
2011-01-01
Information technology (IT) outsourcing is a business trend aimed at reducing costs and enabling companies to concentrate on their core competencies. This qualitative multiple case design research study explored the effects of hidden costs on the operational management of IT outsourcing. The study involved analyzing IT outsourcing agreements as…
Learning and Study Strategies of Students with Traumatic Brain Injury: A Mixed Method Study
ERIC Educational Resources Information Center
Bush, Erin; Hux, Karen; Zickefoose, Samantha; Simanek, Gina; Holmberg, Michelle; Henderson, Ambyr
2011-01-01
The purpose of this research was to explore the perceptions of four college students with severe traumatic brain injury and people associated with them regarding the use of learning skills and study strategies. The researchers employed a concurrent mixed method design using descriptive quantitative data as well as qualitative multiple case study…
N. Suzuki; D.H. Olson
2007-01-01
We review the policies and management approaches used in U.S. Pacific Northwest planted forest to address biodiversity protection. We provide a case-study watershed design from southern Oregon, integrating various stand-to-landscape biodiversity-management approaches.
Contextual Understandings in the TPACK Framework
ERIC Educational Resources Information Center
Swallow, Meredith J. C.; Olofson, Mark W.
2017-01-01
The technological, pedagogical, and content knowledge (TPACK) framework considers the role of technology in teaching. Although TPACK is grounded in context, one limitation is the lack of understanding about the interactions between particular contexts, knowledge development, and instruction. This qualitative multiple-case study was designed to…
Birmann, Brenda M; Andreotti, Gabriella; De Roos, Anneclaire J; Camp, Nicola J; Chiu, Brian C H; Spinelli, John J; Becker, Nikolaus; Benhaim-Luzon, Véronique; Bhatti, Parveen; Boffetta, Paolo; Brennan, Paul; Brown, Elizabeth E; Cocco, Pierluigi; Costas, Laura; Cozen, Wendy; de Sanjosé, Silvia; Foretová, Lenka; Giles, Graham G; Maynadié, Marc; Moysich, Kirsten; Nieters, Alexandra; Staines, Anthony; Tricot, Guido; Weisenburger, Dennis; Zhang, Yawei; Baris, Dalsu; Purdue, Mark P
2017-06-01
Background: Multiple myeloma risk increases with higher adult body mass index (BMI). Emerging evidence also supports an association of young adult BMI with multiple myeloma. We undertook a pooled analysis of eight case-control studies to further evaluate anthropometric multiple myeloma risk factors, including young adult BMI. Methods: We conducted multivariable logistic regression analysis of usual adult anthropometric measures of 2,318 multiple myeloma cases and 9,609 controls, and of young adult BMI (age 25 or 30 years) for 1,164 cases and 3,629 controls. Results: In the pooled sample, multiple myeloma risk was positively associated with usual adult BMI; risk increased 9% per 5-kg/m 2 increase in BMI [OR, 1.09; 95% confidence interval (CI), 1.04-1.14; P = 0.007]. We observed significant heterogeneity by study design ( P = 0.04), noting the BMI-multiple myeloma association only for population-based studies ( P trend = 0.0003). Young adult BMI was also positively associated with multiple myeloma (per 5-kg/m 2 ; OR, 1.2; 95% CI, 1.1-1.3; P = 0.0002). Furthermore, we observed strong evidence of interaction between younger and usual adult BMI ( P interaction <0.0001); we noted statistically significant associations with multiple myeloma for persons overweight (25-<30 kg/m 2 ) or obese (30+ kg/m 2 ) in both younger and usual adulthood (vs. individuals consistently <25 kg/m 2 ), but not for those overweight or obese at only one time period. Conclusions: BMI-associated increases in multiple myeloma risk were highest for individuals who were overweight or obese throughout adulthood. Impact: These findings provide the strongest evidence to date that earlier and later adult BMI may increase multiple myeloma risk and suggest that healthy BMI maintenance throughout life may confer an added benefit of multiple myeloma prevention. Cancer Epidemiol Biomarkers Prev; 26(6); 876-85. ©2017 AACR . ©2017 American Association for Cancer Research.
Robust THP Transceiver Designs for Multiuser MIMO Downlink with Imperfect CSIT
NASA Astrophysics Data System (ADS)
Ubaidulla, P.; Chockalingam, A.
2009-12-01
We present robust joint nonlinear transceiver designs for multiuser multiple-input multiple-output (MIMO) downlink in the presence of imperfections in the channel state information at the transmitter (CSIT). The base station (BS) is equipped with multiple transmit antennas, and each user terminal is equipped with one or more receive antennas. The BS employs Tomlinson-Harashima precoding (THP) for interuser interference precancellation at the transmitter. We consider robust transceiver designs that jointly optimize the transmit THP filters and receive filter for two models of CSIT errors. The first model is a stochastic error (SE) model, where the CSIT error is Gaussian-distributed. This model is applicable when the CSIT error is dominated by channel estimation error. In this case, the proposed robust transceiver design seeks to minimize a stochastic function of the sum mean square error (SMSE) under a constraint on the total BS transmit power. We propose an iterative algorithm to solve this problem. The other model we consider is a norm-bounded error (NBE) model, where the CSIT error can be specified by an uncertainty set. This model is applicable when the CSIT error is dominated by quantization errors. In this case, we consider a worst-case design. For this model, we consider robust (i) minimum SMSE, (ii) MSE-constrained, and (iii) MSE-balancing transceiver designs. We propose iterative algorithms to solve these problems, wherein each iteration involves a pair of semidefinite programs (SDPs). Further, we consider an extension of the proposed algorithm to the case with per-antenna power constraints. We evaluate the robustness of the proposed algorithms to imperfections in CSIT through simulation, and show that the proposed robust designs outperform nonrobust designs as well as robust linear transceiver designs reported in the recent literature.
Utilising family-based designs for detecting rare variant disease associations.
Preston, Mark D; Dudbridge, Frank
2014-03-01
Rare genetic variants are thought to be important components in the causality of many diseases but discovering these associations is challenging. We demonstrate how best to use family-based designs to improve the power to detect rare variant disease associations. We show that using genetic data from enriched families (those pedigrees with greater than one affected member) increases the power and sensitivity of existing case-control rare variant tests. However, we show that transmission- (or within-family-) based tests do not benefit from this enrichment. This means that, in studies where a limited amount of genotyping is available, choosing a single case from each of many pedigrees has greater power than selecting multiple cases from fewer pedigrees. Finally, we show how a pseudo-case-control design allows a greater range of statistical tests to be applied to family data. © 2014 The Authors. Annals of Human Genetics published by John Wiley & Sons Ltd/University College London.
Action and Organizational Learning in an Elevator Company
ERIC Educational Resources Information Center
De Loo, Ivo
2006-01-01
Purpose: To highlight the relevance of management control in action learning programs that aim to foster organizational learning. Design/methodology/approach: Literature review plus case study. The latter consists of archival analysis and multiple interviews. Findings: When action learning programs are built around singular learning experiences,…
ERIC Educational Resources Information Center
Cosbey, Joanna; Muldoon, Deirdre
2017-01-01
This study evaluated the effectiveness of a family-centered feeding intervention, Easing Anxiety Together with Understanding and Perseverance (EAT-UP™), for promoting food acceptance of children with autism spectrum disorder at home. A concurrent multiple-baseline design was used with systematic replication across three families. Baseline was…
Left ventricular assist device malfunction: a systematic approach to diagnosis.
Horton, Steven C; Khodaverdian, Reza; Powers, Amanda; Revenaugh, James; Renlund, Dale G; Moore, Stephanie A; Rasmusson, Brad; Nelson, Karl E; Long, James W
2004-05-05
A protocol was designed to diagnose the common malfunctions of a left ventricular assist device (LVAD). Mechanical circulatory support, primarily with an LVAD, is increasingly used for treatment of advanced heart failure (HF). Left ventricular assist device dysfunction is a recognized complication; but heretofore, a systematic method to accurately diagnose LVAD dysfunction has not been thoroughly described. We developed a catheter-based protocol designed to characterize a normally functioning LVAD and diagnose multiple types of dysfunction. A total of 15 studies of 10 patients supported with an LVAD were reviewed. All patients had been evaluated due to concerns regarding LVAD dysfunction. Of 15 examinations performed, 11 documented severe LVAD inflow valve regurgitation. One of these cases proved to have coexistent severe mitral valve regurgitation. One case was diagnosed with distortion of the LVAD outflow graft. One case of suspected embolization from the pumping chamber excluded the outflow graft as the source of emboli. One study had aortic insufficiency. As LVAD use for treatment of end-stage HF becomes widespread and durations of support are extended, dysfunction will be increasingly prevalent. This catheter-based protocol provided a practical method to diagnose multiple causes of LVAD dysfunction.
Methods to control for unmeasured confounding in pharmacoepidemiology: an overview.
Uddin, Md Jamal; Groenwold, Rolf H H; Ali, Mohammed Sanni; de Boer, Anthonius; Roes, Kit C B; Chowdhury, Muhammad A B; Klungel, Olaf H
2016-06-01
Background Unmeasured confounding is one of the principal problems in pharmacoepidemiologic studies. Several methods have been proposed to detect or control for unmeasured confounding either at the study design phase or the data analysis phase. Aim of the Review To provide an overview of commonly used methods to detect or control for unmeasured confounding and to provide recommendations for proper application in pharmacoepidemiology. Methods/Results Methods to control for unmeasured confounding in the design phase of a study are case only designs (e.g., case-crossover, case-time control, self-controlled case series) and the prior event rate ratio adjustment method. Methods that can be applied in the data analysis phase include, negative control method, perturbation variable method, instrumental variable methods, sensitivity analysis, and ecological analysis. A separate group of methods are those in which additional information on confounders is collected from a substudy. The latter group includes external adjustment, propensity score calibration, two-stage sampling, and multiple imputation. Conclusion As the performance and application of the methods to handle unmeasured confounding may differ across studies and across databases, we stress the importance of using both statistical evidence and substantial clinical knowledge for interpretation of the study results.
Multistate approaches in computational protein design
Davey, James A; Chica, Roberto A
2012-01-01
Computational protein design (CPD) is a useful tool for protein engineers. It has been successfully applied towards the creation of proteins with increased thermostability, improved binding affinity, novel enzymatic activity, and altered ligand specificity. Traditionally, CPD calculations search and rank sequences using a single fixed protein backbone template in an approach referred to as single-state design (SSD). While SSD has enjoyed considerable success, certain design objectives require the explicit consideration of multiple conformational and/or chemical states. Cases where a “multistate” approach may be advantageous over the SSD approach include designing conformational changes into proteins, using native ensembles to mimic backbone flexibility, and designing ligand or oligomeric association specificities. These design objectives can be efficiently tackled using multistate design (MSD), an emerging methodology in CPD that considers any number of protein conformational or chemical states as inputs instead of a single protein backbone template, as in SSD. In this review article, recent examples of the successful design of a desired property into proteins using MSD are described. These studies employing MSD are divided into two categories—those that utilized multiple conformational states, and those that utilized multiple chemical states. In addition, the scoring of competing states during negative design is discussed as a current challenge for MSD. PMID:22811394
Briand, Catherine; Sablier, Juliette; Therrien, Julie-Anne; Charbonneau, Karine; Pelletier, Jean-François; Weiss-Lambrou, Rhoda
2018-07-01
This study aimed to test the feasibility of using a mobile device (Apple technology: iPodTouch®, iPhone® or iPad®) among people with severe mental illness (SMI) in a rehabilitation and recovery process and to document the parameters to be taken into account and the issues involved in implementing this technology in living environments and mental health care settings. A qualitative multiple case study design and multiple data sources were used to understand each case in depth. A clinical and comprehensive analysis of 11 cases was conducted with exploratory and descriptive aims (and the beginnings of explanation building). The multiple-case analysis brought out four typical profiles to illustrate the extent of integration of a personal digital assistant (PDA) as a tool to support mental health rehabilitation and recovery. Each profile highlights four categories of variables identified as determining factors in this process: (1) state of health and related difficulties (cognitive or functional); (2) relationship between comfort level with technology, motivation and personal effort deployed; (3) relationship between support required and support received; and (4) the living environment and follow-up context. This study allowed us to consider the contexts and conditions to be put in place for the successful integration of mobile technology in a mental health rehabilitation and recovery process.
Development and evaluation of a study design typology for human research.
Carini, Simona; Pollock, Brad H; Lehmann, Harold P; Bakken, Suzanne; Barbour, Edward M; Gabriel, Davera; Hagler, Herbert K; Harper, Caryn R; Mollah, Shamim A; Nahm, Meredith; Nguyen, Hien H; Scheuermann, Richard H; Sim, Ida
2009-11-14
A systematic classification of study designs would be useful for researchers, systematic reviewers, readers, and research administrators, among others. As part of the Human Studies Database Project, we developed the Study Design Typology to standardize the classification of study designs in human research. We then performed a multiple observer masked evaluation of active research protocols in four institutions according to a standardized protocol. Thirty-five protocols were classified by three reviewers each into one of nine high-level study designs for interventional and observational research (e.g., N-of-1, Parallel Group, Case Crossover). Rater classification agreement was moderately high for the 35 protocols (Fleiss' kappa = 0.442) and higher still for the 23 quantitative studies (Fleiss' kappa = 0.463). We conclude that our typology shows initial promise for reliably distinguishing study design types for quantitative human research.
ERIC Educational Resources Information Center
Sahin, Elif Adibelli; Deniz, Hasan
2016-01-01
This study explored how four elementary teachers assessed the developmental appropriateness and importance of nine nature of science (NOS) aspects after participating in a yearlong professional development program. A multiple-embedded case study design was employed. The primary data sources included (a) Views of Nature of Science Elementary School…
ERIC Educational Resources Information Center
Bahadur, Waheed; Bano, Amir; Waheed, Zarina; Wahab, Abdul
2017-01-01
The performance of schools is highly dependent on the leadership of school heads, and, flexible leaders accelerate school performance. The purpose of this qualitative study was to examine leadership behavior in selected boys' secondary schools that are performing well. Based on multiple-case study design, four high-performing schools from Quetta…
ERIC Educational Resources Information Center
Gonzalez, Marggie Denise
2016-01-01
This multiple case study examines four groups of secondary mathematics teachers engaged in a Lesson Study approach to professional development where they planned and taught lessons that integrate technology. Informed by current literature, a framework was developed to focus on the dimensions of teacher's knowledge to teach mathematics with…
The Effect of Interactive Technology on Informal Learning and Performance in a Social Setting
ERIC Educational Resources Information Center
Boileau, Timothy
2011-01-01
This study is based on a qualitative multiple case study research design using a mixed methods approach to provide insight into the effect of interactive technology on informal learning and performance in a social business setting inhabited by knowledge workers. The central phenomenon examined is the variance in behavioral intention towards…
ERIC Educational Resources Information Center
Koyuncu, Ilhan; Akyuz, Didem; Cakiroglu, Erdinc
2015-01-01
This study aims to investigate plane geometry problem-solving strategies of prospective mathematics teachers using dynamic geometry software (DGS) and paper-and-pencil (PPB) environments after receiving an instruction with GeoGebra (GGB). Four plane geometry problems were used in a multiple case study design to understand the solution strategies…
Learning and Growing: Trust, Leadership, and Response to Crisis
ERIC Educational Resources Information Center
Sutherland, Ian E.
2017-01-01
Purpose: The purpose of this paper is to explore the nature of trust in a school community related to the leadership response to crisis. Design/Methodology/Approach: This study was a multiple-source qualitative study of a single case of a PreK-12 international school called The Learning School. Findings: The findings revealed the nature of how…
The Influence of Performance Accountability Culture on the Work of High School Principals
ERIC Educational Resources Information Center
Cohen, Michael Ian
2011-01-01
This study examined the way performance accountability culture influenced the work of public high school principals. A qualitative multiple case study design was used to discover the way principals responded to, and coped with, performance accountability culture at the local level. Interviews of nine high school principals in the state of New…
Teacher Perceptions of the Impact of Digital Photo Stories on Students with Autism Spectrum Disorder
ERIC Educational Resources Information Center
Conn, Julie J.
2015-01-01
This study employed a qualitative method, multiple case study design to examine teacher perceptions of the impact of digital photo stories used as an instructional strategy with students with Autism Spectrum Disorder (ASD). Five highly qualified teachers of students with ASD from four public schools in a western North Carolina school district…
Assessing the Impact of Twenty-First Century Rural School Consolidation
ERIC Educational Resources Information Center
Surface, Jeanne
2011-01-01
The purpose of the study was to make a qualitative assessment of the impact of school consolidation on several rural Nebraska communities that have recently lost their schools. This research uses a multiple-case study design with interviews conducted in three Nebraska communities. The data from this research fell into four broad themes: social…
Yolasığmaz, Hacı Ahmet; Keleş, Sedat
2009-01-01
In Turkey, the understanding of planning focused on timber production has given its place on Multiple Use Management (MUM). Because the whole infrastructure of forestry with inventory system leading the way depends on timber production, some cases of bottle neck are expected during the transition period. Database design, probably the most important stage during the transition to MUM, together with the digital basic maps making up the basis of this infrastructure constitute the main point of this article. Firstly, the forest management philosophy of Turkey in the past was shortly touched upon in the article. Ecosystem Based Multiple Use Forest Management (EBMUFM) approaches was briefly introduced. The second stage of the process of EBMUFM, database design was described by examining the classical planning infrastructure and the coverage to be produced and consumed were suggested in the form of lists. At the application stage, two different geographical databases were established with GIS in Balcı Planning Unit of the years 1984 and 2006. Following that the related basic maps are produced. Timely diversity of the planning unit of 20 years is put forward comparatively with regard to the stand parameters such as tree types, age class, development stage, canopy closure, mixture, volume and increment.
Amirian, E Susan; Scheurer, Michael E; Liu, Yanhong; D'Amelio, Anthony M; Houlston, Richard S; Etzel, Carol J; Shete, Sanjay; Swerdlow, Anthony J; Schoemaker, Minouk J; McKinney, Patricia A; Fleming, Sarah J; Muir, Kenneth R; Lophatananon, Artitaya; Bondy, Melissa L
2011-08-01
Despite extensive research on the topic, glioma etiology remains largely unknown. Exploration of potential interactions between single-nucleotide polymorphisms (SNP) of immune genes is a promising new area of glioma research. The case-only study design is a powerful and efficient design for exploring possible multiplicative interactions between factors that are independent of one another. The purpose of our study was to use this exploratory design to identify potential pair wise SNP-SNP interactions from genes involved in several different immune-related pathways for investigation in future studies. The study population consisted of two case groups: 1,224 histologic confirmed, non-Hispanic white glioma cases from the United States and a validation population of 634 glioma cases from the United Kingdom. Polytomous logistic regression, in which one SNP was coded as the outcome and the other SNP was included as the exposure, was utilized to calculate the ORs of the likelihood of cases simultaneously having the variant alleles of two different SNPs. Potential interactions were examined only between SNPs located in different genes or chromosomes. Using this data mining strategy, we found 396 significant SNP-SNP interactions among polymorphisms of immune-related genes that were present in both the U.S. and U.K. study populations. This exploratory study was conducted for the purpose of hypothesis generation, and thus has provided several new hypotheses that can be tested using traditional case-control study designs to obtain estimates of risk. This is the first study, to our knowledge, to take this novel approach to identifying SNP-SNP interactions relevant to glioma etiology. ©2011 AACR.
Collaborative Strategic Decision Making in School Districts
ERIC Educational Resources Information Center
Brazer, S. David; Rich, William; Ross, Susan A.
2010-01-01
Purpose: The dual purpose of this paper is to determine how superintendents in US school districts work with stakeholders in the decision-making process and to learn how different choices superintendents make affect decision outcomes. Design/methodology/approach: This multiple case study of three school districts employs qualitative methodology to…
Middle School Physical Education Teachers' Perspectives on Overweight Students
ERIC Educational Resources Information Center
Doolittle, Sarah A.; Rukavina, Paul B.; Li, Weidong; Manson, Mara; Beale, Angela
2016-01-01
Using the Social Ecological Constraints model, a qualitative multiple case study design was used to explore experienced and committed middle school physical education teachers' perspectives on overweight and obese students (OWS), and how and why they acted to include OWS in physical education and physical activity opportunities in their school…
Long-Term Effect of Prefrontal Lobotomy on Verbal Fluency in Patients with Schizophrenia
ERIC Educational Resources Information Center
Stip, Emmanuel; Bigras, Marie-Josee.; Mancini-Marie, Adham; Cosset, Marie-Eve.; Black, Deborah; Lecours, Andre-Roch
2004-01-01
Objective: This study investigated the long-term effects of bilateral prefrontal leukotomy on lexical abilities in schizophrenia subjects. Method: We compared performances of leukotomized (LSP), non-leukotomized schizophrenia patients (NLSP) and normal controls, using a test of verbal fluency. Multiple case and triple comparison design were…
Learner Analysis Framework for Globalized E-Learning: A Case Study
ERIC Educational Resources Information Center
Saxena, Mamta
2011-01-01
The shift to technology-mediated modes of instructional delivery and increased global connectivity has led to the rise in globalized e-learning programs. Educational institutions face multiple challenges as they seek to design effective, engaging, and culturally competent instruction for an increasingly diverse learner population. The purpose of…
The Effects of Mobile Collaborative Activities in a Second Language Course
ERIC Educational Resources Information Center
Ilic, Peter
2015-01-01
This research is designed to explore the areas of collaborative learning and the use of smartphones as a support for collaborative learning through a year-long exploratory multiple case study approach integrating both qualitative and quantitative data analysis. Qualitative exploratory interviews are combined with Multidimensional Scaling Analysis…
An Indonesian Model of Successful School Leadership
ERIC Educational Resources Information Center
Raihani
2008-01-01
Purpose--This paper seeks to explore principals leadership in successful Indonesian secondary schools from the perspectives of multiple sources of data. Design/methodology/approach--Inspired by the ISSPP, three schools which met the set criteria of successful schools were selected to be the cases for this study. Within each, individual or group…
Designing Art Exhibitions in an Educational Virtual World
ERIC Educational Resources Information Center
Julian, June; Crooks, Julian
2011-01-01
Demonstrating the multiple features of the Cerulean Gallery in Second Life, this research report showcases several exemplar exhibits created by students, artists, and museums. Located in The Educational Media Center, a Second Life teaching and social space, the Cerulean Gallery exhibits functioned as case studies that tested its effectiveness as…
Learning Spaces and Collaborative Work: Barriers or Supports?
ERIC Educational Resources Information Center
King, Hayley
2016-01-01
Drawing on 18 months of fieldwork, this article discusses the use of physical, virtual and social space to support collaborative work in translator education programs. The study adopted a contrastive ethnography approach that incorporated single- and multiple-case design rationales for site selection. Extended observation, informal chats and…
Principals and Teachers "Craft Coherence" among Accountability Policies
ERIC Educational Resources Information Center
Stosich, Elizabeth Leisy
2018-01-01
Purpose: The purpose of this paper is to examine how US school leaders and teachers make sense of multiple accountability policies, including the Common Core State Standards and teacher evaluation, and how this process relates to school priorities and classroom practice. Design/methodology/approach: This study uses a comparative case study…
Multiple Approaches to Design Education
ERIC Educational Resources Information Center
Fox, Richard L.; And Others
1974-01-01
Discusses implementation of Sloan Foundation projects at the Case Western School of Engineering, including the development of a computer assisted mechanical structural design course, the establishment of a complex systems laboratory, and personnel views of industry-university design projects. (CC)
McKinlay, Eileen M.; Morgan, Sonya J.; Gray, Ben V.; Macdonald, Lindsay M.; Pullon, Susan R.H.
2017-01-01
Background The increase in multimorbidity or co-occurring chronic illnesses is a leading healthcare concern. Patients with multimorbidity require ongoing care from many different professionals and agencies, and often report a lack of integrated care. Objective To explore the daily help-seeking behaviours of patients with multimorbidity, including which health professionals they seek help from, how professionals work together, and perceptions and characteristics of effective interprofessional, interagency multimorbidity care. Design Using a case study observational research design, multiple data sources were assembled for four patients with multimorbidity, identified by two general practitioners in New Zealand. In this paper, two case studies are presented, including the recorded instances of contact and communication between patients and professionals, and between professionals. Professional interactions were categorized as consultation, coordination, or collaboration. Results The two case studies illustrated two female patients with likely similar educational levels, but with different profiles of multimorbidity, social circumstances, and personal capabilities, involving various professionals and agencies. Engagement between professionals showed varying levels of interaction and a lack of clarity about leadership or care coordination. The majority of interactions were one-to-one consultations and rarely involved coordination and collaboration. Patients were rarely included in communications between professionals. Conclusion Cases constructed from multiple data sources illustrate the complexity of day-to-day, interprofessional, interagency multimorbidity care. While consultation is the most frequent mode of professional interaction, targeted coordinated and collaborative interactions (including the patient) are highly effective activities. Greater attention should be given to developing and facilitating these interactions and determining who should lead them. PMID:29090190
Attrition Bias Related to Missing Outcome Data: A Longitudinal Simulation Study.
Lewin, Antoine; Brondeel, Ruben; Benmarhnia, Tarik; Thomas, Frédérique; Chaix, Basile
2018-01-01
Most longitudinal studies do not address potential selection biases due to selective attrition. Using empirical data and simulating additional attrition, we investigated the effectiveness of common approaches to handle missing outcome data from attrition in the association between individual education level and change in body mass index (BMI). Using data from the two waves of the French RECORD Cohort Study (N = 7,172), we first examined how inverse probability weighting (IPW) and multiple imputation handled missing outcome data from attrition in the observed data (stage 1). Second, simulating additional missing data in BMI at follow-up under various missing-at-random scenarios, we quantified the impact of attrition and assessed how multiple imputation performed compared to complete case analysis and to a perfectly specified IPW model as a gold standard (stage 2). With the observed data in stage 1, we found an inverse association between individual education and change in BMI, with complete case analysis, as well as with IPW and multiple imputation. When we simulated additional attrition under a missing-at-random pattern (stage 2), the bias increased with the magnitude of selective attrition, and multiple imputation was useless to address it. Our simulations revealed that selective attrition in the outcome heavily biased the association of interest. The present article contributes to raising awareness that for missing outcome data, multiple imputation does not do better than complete case analysis. More effort is thus needed during the design phase to understand attrition mechanisms by collecting information on the reasons for dropout.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Kyong Ju, E-mail: kjkim@cau.ac.kr; Yun, Won Gun, E-mail: ogun78@naver.com; Cho, Namho, E-mail: nhc51@cau.ac.kr
The late rise in global concern for environmental issues such as global warming and air pollution is accentuating the need for environmental assessments in the construction industry. Promptly evaluating the environmental loads of the various design alternatives during the early stages of a construction project and adopting the most environmentally sustainable candidate is therefore of large importance. Yet, research on the early evaluation of a construction project's environmental load in order to aid the decision making process is hitherto lacking. In light of this dilemma, this study proposes a model for estimating the environmental load by employing only the mostmore » basic information accessible during the early design phases of a project for the pre-stressed concrete (PSC) beam bridge, the most common bridge structure. Firstly, a life cycle assessment (LCA) was conducted on the data from 99 bridges by integrating the bills of quantities (BOQ) with a life cycle inventory (LCI) database. The processed data was then utilized to construct a case based reasoning (CBR) model for estimating the environmental load. The accuracy of the estimation model was then validated using five test cases; the model's mean absolute error rates (MAER) for the total environmental load was calculated as 7.09%. Such test results were shown to be superior compared to those obtained from a multiple-regression based model and a slab area base-unit analysis model. Henceforth application of this model during the early stages of a project is expected to highly complement environmentally friendly designs and construction by facilitating the swift evaluation of the environmental load from multiple standpoints. - Highlights: • This study is to develop the model of assessing the environmental impacts on LCA. • Bills of quantity from completed designs of PSC Beam were linked with the LCI DB. • Previous cases were used to estimate the environmental load of new case by CBR model. • CBR model produces more accurate estimations (7.09%) than other conventional models. • This study supports decision making process in the early stage of a new construction case.« less
ERIC Educational Resources Information Center
Lackney, Jeffery A.
Environmental factors are being increasingly recognized as playing a role in school effectiveness and educational outcomes. Volume 1 examines what is known concerning the diagnosis, design, and management of environmental quality in schools, and the perceived relationship between environmental quality and educational outcomes, as revealed in an…
Multiple degree of freedom object recognition using optical relational graph decision nets
NASA Technical Reports Server (NTRS)
Casasent, David P.; Lee, Andrew J.
1988-01-01
Multiple-degree-of-freedom object recognition concerns objects with no stable rest position with all scale, rotation, and aspect distortions possible. It is assumed that the objects are in a fairly benign background, so that feature extractors are usable. In-plane distortion invariance is provided by use of a polar-log coordinate transform feature space, and out-of-plane distortion invariance is provided by linear discriminant function design. Relational graph decision nets are considered for multiple-degree-of-freedom pattern recognition. The design of Fisher (1936) linear discriminant functions and synthetic discriminant function for use at the nodes of binary and multidecision nets is discussed. Case studies are detailed for two-class and multiclass problems. Simulation results demonstrate the robustness of the processors to quantization of the filter coefficients and to noise.
NASA Astrophysics Data System (ADS)
Shea, Nicole A.; Mouza, Chrystalla; Drewes, Andrea
2016-04-01
In this work, we present the design, implementation, and initial outcomes of the Climate Academy, a hybrid professional development program delivered through a combination of face-to-face and online interactions, intended to prepare formal and informal science teachers (grades 5-16) in teaching about climate change. The Climate Academy was designed around core elements of successful environmental professional development programs and aligned with practices advocated in benchmarked science standards. Data were collected from multiple sources including observations of professional development events, participants' reflections on their learning, and collection of instructional units designed during the Academy. Data were also collected from a focal case study teacher in a middle school setting. Case study data included classroom observations, teacher interviews, and student beliefs toward climate change. Results indicated that the Climate Academy fostered increased learning among participants of both climate science content and pedagogical strategies for teaching about climate change. Additionally, results indicated that participants applied their new learning in the design of climate change instructional units. Finally, results from the case study indicated positive impacts on student beliefs and greater awareness about climate change. Results have implications for the design of professional development programs on climate change, a topic included for the first time in national standards.
ERIC Educational Resources Information Center
Egbufor, Dorothy Chukwudumebi
2017-01-01
The chief aim of this study was to develop a grounded theory of ethical leadership with school leaders in Southern Nigeria, utilizing a qualitative constructivist paradigm and multiple case study design. There is growing interest in public service of ethics (Barberis, 2001). The study of ethics has been a part of the [school] leadership erudition…
NASA Astrophysics Data System (ADS)
dos Santos Fradinho, Jorge Miguel
2014-05-01
Our understanding of enterprise systems (ES) is gradually evolving towards a sense of design which leverages multidisciplinary bodies of knowledge that may bolster hybrid research designs and together further the characterisation of ES operation and performance. This article aims to contribute towards ES design theory with its hospital enterprise systems design (HESD) framework, which reflects a rich multidisciplinary literature and two in-depth hospital empirical cases from the US and UK. In doing so it leverages systems thinking principles and traditionally disparate bodies of knowledge to bolster the theoretical evolution and foundation of ES. A total of seven core ES design elements are identified and characterised with 24 main categories and 53 subcategories. In addition, it builds on recent work which suggests that hospital enterprises are comprised of multiple internal ES configurations which may generate different levels of performance. Multiple sources of evidence were collected including electronic medical records, 54 recorded interviews, observation, and internal documents. Both in-depth cases compare and contrast higher and lower performing ES configurations. Following literal replication across in-depth cases, this article concludes that hospital performance can be improved through an enriched understanding of hospital ES design.
Applying a Genetic Algorithm to Reconfigurable Hardware
NASA Technical Reports Server (NTRS)
Wells, B. Earl; Weir, John; Trevino, Luis; Patrick, Clint; Steincamp, Jim
2004-01-01
This paper investigates the feasibility of applying genetic algorithms to solve optimization problems that are implemented entirely in reconfgurable hardware. The paper highlights the pe$ormance/design space trade-offs that must be understood to effectively implement a standard genetic algorithm within a modem Field Programmable Gate Array, FPGA, reconfgurable hardware environment and presents a case-study where this stochastic search technique is applied to standard test-case problems taken from the technical literature. In this research, the targeted FPGA-based platform and high-level design environment was the Starbridge Hypercomputing platform, which incorporates multiple Xilinx Virtex II FPGAs, and the Viva TM graphical hardware description language.
Literacy Teaching and Learning in Two Kindergarten Classrooms in a School Labeled At-Risk.
ERIC Educational Resources Information Center
Barone, Diane
2002-01-01
Used multiple case-study design in year-long study to assess literacy teaching and learning in two half-day kindergartens at an at-risk school. Found that literacy teaching most often centered on letter recognition and sound/symbol relationships, with few opportunities for children to engage in meaningful dialogue centered on books. Four of 11…
ERIC Educational Resources Information Center
Pruijssers, Addy; van Meijel, Berno; Maaskant, Marian; Keeman, Noortje; van Achterberg, Theo
2016-01-01
Background: People with intellectual disabilities often have a multitude of concurrent problems due to the combination of cognitive impairments, psychiatric disorders (particularly anxiety) and related challenging behaviours. Diagnoses in people with intellectual disabilities are complicated. This study evaluates the quality of the diagnoses and…
Fu, Wei; Shi, Qiyuan; Prosperi, Christine; Wu, Zhenke; Hammitt, Laura L.; Feikin, Daniel R.; Baggett, Henry C.; Howie, Stephen R.C.; Scott, J. Anthony G.; Murdoch, David R.; Madhi, Shabir A.; Thea, Donald M.; Brooks, W. Abdullah; Kotloff, Karen L.; Li, Mengying; Park, Daniel E.; Lin, Wenyi; Levine, Orin S.; O’Brien, Katherine L.; Zeger, Scott L.
2017-01-01
Abstract In pneumonia, specimens are rarely obtained directly from the infection site, the lung, so the pathogen causing infection is determined indirectly from multiple tests on peripheral clinical specimens, which may have imperfect and uncertain sensitivity and specificity, so inference about the cause is complex. Analytic approaches have included expert review of case-only results, case–control logistic regression, latent class analysis, and attributable fraction, but each has serious limitations and none naturally integrate multiple test results. The Pneumonia Etiology Research for Child Health (PERCH) study required an analytic solution appropriate for a case–control design that could incorporate evidence from multiple specimens from cases and controls and that accounted for measurement error. We describe a Bayesian integrated approach we developed that combined and extended elements of attributable fraction and latent class analyses to meet some of these challenges and illustrate the advantage it confers regarding the challenges identified for other methods. PMID:28575370
7 CFR 810.108 - Special grade designations.
Code of Federal Regulations, 2010 CFR
2010-01-01
.... Multiple special grade designations will be listed in alphabetical order. In the case of treated wheat, the official certificate shall show whether the wheat has been scoured, limed, washed, sulfured, or otherwise...
Multiple imputation methods for bivariate outcomes in cluster randomised trials.
DiazOrdaz, K; Kenward, M G; Gomes, M; Grieve, R
2016-09-10
Missing observations are common in cluster randomised trials. The problem is exacerbated when modelling bivariate outcomes jointly, as the proportion of complete cases is often considerably smaller than the proportion having either of the outcomes fully observed. Approaches taken to handling such missing data include the following: complete case analysis, single-level multiple imputation that ignores the clustering, multiple imputation with a fixed effect for each cluster and multilevel multiple imputation. We contrasted the alternative approaches to handling missing data in a cost-effectiveness analysis that uses data from a cluster randomised trial to evaluate an exercise intervention for care home residents. We then conducted a simulation study to assess the performance of these approaches on bivariate continuous outcomes, in terms of confidence interval coverage and empirical bias in the estimated treatment effects. Missing-at-random clustered data scenarios were simulated following a full-factorial design. Across all the missing data mechanisms considered, the multiple imputation methods provided estimators with negligible bias, while complete case analysis resulted in biased treatment effect estimates in scenarios where the randomised treatment arm was associated with missingness. Confidence interval coverage was generally in excess of nominal levels (up to 99.8%) following fixed-effects multiple imputation and too low following single-level multiple imputation. Multilevel multiple imputation led to coverage levels of approximately 95% throughout. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.
Kwakkenbos, Linda; Rietveld, Leonie; den Broeder, Alfons A; de Bie, Rob A; van den Ende, Cornelia H M
2012-01-01
Objectives To evaluate the feasibility and potential effectiveness of a 12-week, non-pharmacological multidisciplinary intervention in patients with generalised osteoarthritis (GOA). Design A randomised, concurrent, multiple-baseline single-case design. During the baseline period, the intervention period and the postintervention period, all participants completed several health outcomes twice a week on Visual Analogue Scales. Setting Rheumatology outpatient department of a specialised hospital in the Netherlands. Participants 1 man and four women (aged 51–76 years) diagnosed with GOA. Primary outcome measures To assess feasibility, the authors assessed the number of dropouts and adverse events, adherence rates and patients' satisfaction. Secondary outcome measures To assess the potential effectiveness, the authors assessed pain and self-efficacy using visual data inspection and randomisation tests. Results The intervention was feasible in terms of adverse events (none) and adherence rate but not in terms of participants' satisfaction with the intervention. Visual inspection of the data and randomisation testing demonstrated no effects on pain (p=0.93) or self-efficacy (p=0.85). Conclusions The results of the present study indicate that the proposed intervention for patients with GOA was insufficiently feasible and effective. The data obtained through this multiple-baseline study have highlighted several areas in which the therapy programme can be optimised. PMID:22815466
Design of a clinical notification system.
Wagner, M M; Tsui, F C; Pike, J; Pike, L
1999-01-01
We describe the requirements and design of an enterprise-wide notification system. From published descriptions of notification schemes, our own experience, and use cases provided by diverse users in our institution, we developed a set of functional requirements. The resulting design supports multiple communication channels, third party mappings (algorithms) from message to recipient and/or channel of delivery, and escalation algorithms. A requirement for multiple message formats is addressed by a document specification. We implemented this system in Java as a CORBA object. This paper describes the design and current implementation of our notification system.
The Caterpillar Game: A SW-PBIS Aligned Classroom Management System
ERIC Educational Resources Information Center
Floress, Margaret T.; Jacoby, Amber L.
2017-01-01
The Caterpillar Game is a classroom management system that is aligned with School-wide Positive Behavioral Interventions and Supports standards. A single-case, multiple-baseline design was used to evaluate the effects of the Caterpillar Game on disruptive student behavior and teacher praise. Three classrooms were included in the study (preschool,…
Engineering Professional Development Design for Secondary School Teachers: A Multiple Case Study
ERIC Educational Resources Information Center
Daugherty, Jenny Lynn
2009-01-01
The complexity of engineering and its integration into K-12 education have resulted in a variety of issues requiring sustained empirical research (Johnson, Burghardt, & Daugherty, 2008). One particular area of need, given the emphasis on teacher effects on student learning, is to research engineering-oriented teacher professional development. A…
Using Formative Assessment to Support Complex Learning in Conditions of Social Adversity
ERIC Educational Resources Information Center
Crossouard, Barbara
2011-01-01
This article reports on research into formative assessment within a task design that produces multiple opportunities for teacher and pupil dialogue. It draws upon in-depth case studies conducted in schools in socially deprived areas of Scotland, using policy and documentary analysis, video-observation, and an iterative series of interviews with…
Coaching Preservice Teachers to Teach Play Skills to Children with Disabilities
ERIC Educational Resources Information Center
Barton, Erin E.; Chen, Ching-I; Pribble, Lois; Pomes, Maria; Kim, Young-Ah
2013-01-01
The purpose of this article is to describe two studies that examined the effects of training and coaching on preservice teachers' implementation of an intervention focused on teaching play to young children with disabilities. A multiple-baseline across teachers single-case research design was used to systematically examine the relation between…
The Development of Digital Literacy and Inclusion Skills of Public Librarians
ERIC Educational Resources Information Center
Martzoukou, Konstantina; Elliott, Joanneke
2016-01-01
This paper examines the extent to which public librarians are successfully prepared to engage the community in digital literacy and inclusion. A qualitative, multiple case study research design was chosen, using an analysis of policy documents and existing training programs offered by the libraries together with semi-structured interviews with…
ERIC Educational Resources Information Center
Redmon, Stephen Thomas
2013-01-01
This multiple-case study explored the nature of the experiences of family members of service-disabled veterans who participated in the Entrepreneurship Bootcamp for Veterans Family Program (EBV-F), an entrepreneurial learning and coaching program designed to assist family members of service-disabled veterans to support the discontinuous life…
ERIC Educational Resources Information Center
Friedman, Mollie; Woods, Juliann
2015-01-01
This study investigates the use of a situated coaching protocol in Early Head Start (EHS) classrooms to increase teachers' use of communication facilitation strategies with children identified with delays during typical play and caregiving routines. A single-case, multiple baseline design across 3 EHS teachers and children with communication…
Who Moved My Curriculum? Leadership Preparation Programs and the Core Technology of Schools
ERIC Educational Resources Information Center
Doolittle, Gini; Browne, Evelyn Gallagher
2011-01-01
This cross-case study utilizes the publically available data of three urban low-performing, low-socioeconomic-status districts designated as "districts in need of improvement" under No Child Left Behind legislation. Despite multiple interventions aimed at improving student learning, these and other districts remain in corrective action.…
ERIC Educational Resources Information Center
Biggers, Mandy; Forbes, Cory T.
2012-01-01
Using the National Research Council's inquiry continuum framework, we use a multiple-case study research design to investigate the teacher- and student-directedness of elementary preservice teachers' planned and enacted science lessons and their pedagogical reasoning about science instruction during a semester-long science methods course. Our…
Design, Customization and Implementation of Energy Simulation with 5E Model in Elementary Classroom
ERIC Educational Resources Information Center
Lye, Sze Yee; Wee, Loo Kang; Kwek, Yao Chie; Abas, Suriati; Tay, Lee Yong
2014-01-01
Science simulations are popular among educators as such simulations afford for multiple visual representation and interactivity. Despite the popularity and abundance on the internet, our literature review suggested little research has been conducted on the use of simulation in elementary school. Thus, an exploratory pilot case study was conducted…
The Power of Verbal Scaffolding: "Showing" Beginning Readers How to Use Reading Strategies
ERIC Educational Resources Information Center
Ankrum, Julie W.; Genest, Maria T.; Belcastro, Elizabeth G.
2014-01-01
A single case study design was employed to describe the nature of one teacher's verbal scaffolding used during differentiated reading instruction in a kindergarten classroom. The teacher participant was selected from a group of exemplary teachers nominated from two school districts in southwestern Pennsylvania. Multiple sources of data, including…
ERIC Educational Resources Information Center
Maye, Kelly M.
2012-01-01
Cognitive and biophysical factors have been considered contributors linked to identifiable markers of obsessive compulsive and anxiety disorders. Research demonstrates multiple causes and mixed results for the short-term success of educational programs designed to ameliorate problems that children with obsessive compulsive and anxiety disorders…
ERIC Educational Resources Information Center
Datchuk, Shawn M.; Kubina, Richard M., Jr.
2017-01-01
The present study used a multiple-baseline, single-case experimental design to investigate the effects of a multicomponent intervention on construction of simple sentences and word sequences. The intervention entailed sequential delivery of sentence instruction and frequency building to a performance criterion and paragraph instruction.…
ERIC Educational Resources Information Center
Walker, William S., III
2016-01-01
In this research, I investigated teachers' interpretations of the goals of professional development and factors that contributed to enacted instructional practices. A multiple-case study design was used to examine the interpretations of four high school teachers participating in a year-long professional development program with a standards-based…
ERIC Educational Resources Information Center
Vilaça, Teresa
2017-01-01
Purpose: The purpose of this paper is to discuss teachers' practices, barriers and facilitating factors associated with a regional school-based action-oriented sexuality education (SE) project with the use of information and communication technology. Design/methodology/approach: This qualitative research was anchored in a constructivist paradigm,…
More than an Intervention: Strategies for Increasing Diversity and Inclusion in STEM
ERIC Educational Resources Information Center
Jones, Sosanya
2016-01-01
Purpose: This paper aims to provide insight into the strategies used by leaders of graduate school preparation programs for science, technology, engineering and mathematics (STEM) to recruit and retain graduate students of color within STEM fields. Design/methodology/approach: This paper is a qualitative multiple-case study using a snowball sample…
Data Informed Decision Making--Perspectives of Oklahoma Superintendents
ERIC Educational Resources Information Center
Kettles, Thomas D.
2017-01-01
This descriptive, multiple case study was designed to convey a clear portrayal of the DIDM practice of six superintendents and to provide a description of what these superintendents employ during their decision making process. The ability of local education leaders to strategically influence the use of data for decision making has a large effect…
NASA Astrophysics Data System (ADS)
Brown, Nancy Melamed
This qualitative investigation extends the study of teacher learning within a reform-based community of practice model of professional development. This long-term, multiple case study examined three experienced teachers' transformations in thinking about science instruction. Data were collected during the three years of the Guided Inquiry supporting Multiple Literacies research project, designed to develop instructional practices informed by a socio-cultural, inquiry-based orientation. Data sources included: transcripts of semi-structured interviews collected at strategic points, the teacher's journals, initial application information, and teachers' written case studies. Using an interpretive case study approach, tenets of the teachers' orientations were identified through a recursive process. Results are organized to reflect two principles that were integral to the design of the professional development community. The first principle describes changes in teachers' orientations about the goals and characteristics of science instruction in the elementary grades. The second describes changes about teachers' knowledge about themselves as learners and the influence of this knowledge on their thinking about science instruction and student learning. Illustrative findings indicate that: (a) it is possible for teachers' language regarding conceptions of their practice to change with only superficial change in their orientations, (b) teachers can hold dualistic ways of thinking about their practice, (c) in some cases, teachers use a significant amount of autobiography about their own learning to explain their practice; over time, this was replaced with warrants using the language that developed within the professional development community, and (d) long-term case studies revealed differences in orientations that emerged and were refined over time. These findings provide strong support for communities of practice as a model of professional development and hold implications for advancing teacher learning.
NASA Astrophysics Data System (ADS)
Rebello, Carina M.
This study explored the effects of alternative forms of argumentation on undergraduates' physics solutions in introductory calculus-based physics. A two-phase concurrent mixed methods design was employed to investigate relationships between undergraduates' written argumentation abilities, conceptual quality of problem solutions, as well as approaches and strategies for solving argumentative physics problems across multiple physics topics. Participants were assigned via stratified sampling to one of three conditions (control, guided construct, or guided evaluate) based on gender and pre-test scores on a conceptual instrument. The guided construct and guided evaluate groups received tasks and prompts drawn from literature to facilitate argument construction or evaluation. Using a multiple case study design, with each condition serving as a case, interviews were conducted consisting of a think-aloud problem solving session paired with a semi-structured interview. The analysis of problem solving strategies was guided by the theoretical framework on epistemic games adapted by Tuminaro and Redish (2007). This study provides empirical evidence that integration of written argumentation into physics problems can potentially improve the conceptual quality of solutions, expand their repertoire of problem solving strategies and show promise for addressing the gender gap in physics. The study suggests further avenues for research in this area and implications for designing and implementing argumentation tasks in introductory college physics.
Morgan, Sonya J; Pullon, Susan R H; Macdonald, Lindsay M; McKinlay, Eileen M; Gray, Ben V
2017-06-01
Case study research is a comprehensive method that incorporates multiple sources of data to provide detailed accounts of complex research phenomena in real-life contexts. However, current models of case study research do not particularly distinguish the unique contribution observation data can make. Observation methods have the potential to reach beyond other methods that rely largely or solely on self-report. This article describes the distinctive characteristics of case study observational research, a modified form of Yin's 2014 model of case study research the authors used in a study exploring interprofessional collaboration in primary care. In this approach, observation data are positioned as the central component of the research design. Case study observational research offers a promising approach for researchers in a wide range of health care settings seeking more complete understandings of complex topics, where contextual influences are of primary concern. Future research is needed to refine and evaluate the approach.
Lessard, Chantale; Contandriopoulos, André-Pierre; Beaulieu, Marie-Dominique
2009-01-01
Background A considerable amount of resource allocation decisions take place daily at the point of the clinical encounter; especially in primary care, where 80 percent of health problems are managed. Ignoring economic evaluation evidence in individual clinical decision-making may have a broad impact on the efficiency of health services. To date, almost all studies on the use of economic evaluation in decision-making used a quantitative approach, and few investigated decision-making at the clinical level. An important question is whether economic evaluations affect clinical practice. The project is an intervention research study designed to understand the role of economic evaluation in the decision-making process of family physicians (FPs). The contributions of the project will be from the perspective of Pierre Bourdieu's sociological theory. Methods/design A qualitative research strategy is proposed. We will conduct an embedded multiple-case study design. Ten case studies will be performed. The FPs will be the unit of analysis. The sampling strategies will be directed towards theoretical generalization. The 10 selected cases will be intended to reflect a diversity of FPs. There will be two embedded units of analysis: FPs (micro-level of analysis) and field of family medicine (macro-level of analysis). The division of the determinants of practice/behaviour into two groups, corresponding to the macro-structural level and the micro-individual level, is the basis for Bourdieu's mode of analysis. The sources of data collection for the micro-level analysis will be 10 life history interviews with FPs, documents and observational evidence. The sources of data collection for the macro-level analysis will be documents and 9 open-ended, focused interviews with key informants from medical associations and academic institutions. The analytic induction approach to data analysis will be used. A list of codes will be generated based on both the original framework and new themes introduced by the participants. We will conduct within-case and cross-case analyses of the data. Discussion The question of the role of economic evaluation in FPs' decision-making is of great interest to scientists, health care practitioners, managers and policy-makers, as well as to consultants, industry, and society. It is believed that the proposed research approach will make an original contribution to the development of knowledge, both empirical and theoretical. PMID:19210787
NASA Astrophysics Data System (ADS)
Mildenhall, Paula; Sherriff, Barbara
2017-06-01
Recent research indicates that using multimodal learning experiences can be effective in teaching mathematics. Using a social semiotic lens within a participationist framework, this paper reports on a professional learning collaboration with a primary school teacher designed to explore the use of metaphors and modalities in mathematics instruction. This video case study was conducted in a year 2 classroom over two terms, with the focus on building children's understanding of computational strategies. The findings revealed that the teacher was able to successfully plan both multimodal and multiple metaphor learning experiences that acted as semiotic resources to support the children's understanding of abstract mathematics. The study also led to implications for teaching when using multiple metaphors and multimodalities.
Ren, Jingzheng; Dong, Liang; Sun, Lu; Goodsite, Michael Evan; Tan, Shiyu; Dong, Lichun
2015-01-01
The aim of this work was to develop a model for optimizing the life cycle cost of biofuel supply chain under uncertainties. Multiple agriculture zones, multiple transportation modes for the transport of grain and biofuel, multiple biofuel plants, and multiple market centers were considered in this model, and the price of the resources, the yield of grain and the market demands were regarded as interval numbers instead of constants. An interval linear programming was developed, and a method for solving interval linear programming was presented. An illustrative case was studied by the proposed model, and the results showed that the proposed model is feasible for designing biofuel supply chain under uncertainties. Copyright © 2015 Elsevier Ltd. All rights reserved.
Maggin, Daniel M; Swaminathan, Hariharan; Rogers, Helen J; O'Keeffe, Breda V; Sugai, George; Horner, Robert H
2011-06-01
A new method for deriving effect sizes from single-case designs is proposed. The strategy is applicable to small-sample time-series data with autoregressive errors. The method uses Generalized Least Squares (GLS) to model the autocorrelation of the data and estimate regression parameters to produce an effect size that represents the magnitude of treatment effect from baseline to treatment phases in standard deviation units. In this paper, the method is applied to two published examples using common single case designs (i.e., withdrawal and multiple-baseline). The results from these studies are described, and the method is compared to ten desirable criteria for single-case effect sizes. Based on the results of this application, we conclude with observations about the use of GLS as a support to visual analysis, provide recommendations for future research, and describe implications for practice. Copyright © 2011 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Lucyshyn, Joseph M.; Albin, Richard W.; Horner, Robert H.; Mann, Jane C.; Mann, James A.; Wadsworth, Gina
2007-01-01
This study examined the efficacy, social validity, and durability of a positive behavior support (PBS) approach with the family of a girl with autism and severe problem behavior. The study was conducted across a 10-year period beginning when the child was 5 years old. A multiple baseline across family routines design evaluated the functional…
Design and Redesign of a Multimodal Classroom Task--Implications for Teaching and Learning
ERIC Educational Resources Information Center
Öman, Anne; Sofkova Hashemi, Sylvana
2015-01-01
Digital technologies are increasingly implemented in Swedish schools, which impact on education in the contemporary classroom. Screen-based practice opens up for new forms and multiplicity of representations, taking into account that language in a globalized society is more than reading and writing skills. This paper presents a case study of…
ERIC Educational Resources Information Center
de Koster, S.; Kuiper, E.; Volman, M.
2012-01-01
The fit between existing educational practices and promoted classroom use of information and communication technologies is increasingly recognized as a factor in successful integration of such technologies in classroom practice. Using a descriptive multiple-case study design, we characterize the types of information and communication technology…
Young Children's Knowledge about the Moon: A Complex Dynamic System
ERIC Educational Resources Information Center
Venville, Grady J.; Louisell, Robert D.; Wilhelm, Jennifer A.
2012-01-01
The purpose of this research was to use a multidimensional theoretical framework to examine young children's knowledge about the Moon. The research was conducted in the interpretive paradigm and the design was a multiple case study of ten children between the ages of three and eight from the USA and Australia. A detailed, semi-structured interview…
ERIC Educational Resources Information Center
Riggie, Jennifer
2013-01-01
The purpose of this study was to examine the relationship between coaching provided with bug-in-ear technology, the frequency of the early childhood educators' use of targeted communication strategies and children's expressive communication. Four multiple-baseline single-case design experiments were completed to evaluate these relationships.…
ERIC Educational Resources Information Center
Yakubova, Gulnoza; Hughes, Elizabeth M.; Hornberger, Erin
2015-01-01
The purpose of this study was to determine the effectiveness of a point-of-view video modeling intervention to teach mathematics problem-solving when working on word problems involving subtracting mixed fractions with uncommon denominators. Using a multiple-probe across students design of single-case methodology, three high school students with…
ERIC Educational Resources Information Center
Yakubova, Gulnoza; Hughes, Elizabeth M.; Shinaberry, Megan
2016-01-01
The purpose of this study was to determine the effectiveness of a video modeling intervention with concrete-representational-abstract instructional sequence in teaching mathematics concepts to students with autism spectrum disorder (ASD). A multiple baseline across skills design of single-case experimental methodology was used to determine the…
ERIC Educational Resources Information Center
Labrecque, Joane; Marchand, Andre; Dugas, Michel J.; Letarte, Andree
2007-01-01
The goal of this study was to evaluate the efficacy of cognitive-behavioral therapy for comorbid panic disorder with agoraphobia (PDA) and generalized anxiety disorder (GAD) by combining treatment strategies for both disorders. A single-case, multiple-baseline design across participants was used. Three participants with primary PDA and secondary…
ERIC Educational Resources Information Center
Labrecque, Joane; Dugas, Michel J.; Marchand, Andre; Letarte, Andree
2006-01-01
The goal of this study was to evaluate the efficacy of a cognitive-behavioral treatment package for comorbid generalized anxiety disorder (GAD) and panic disorder with agoraphobia (PDA). A single-case, multiple-baseline, across-subjects design was used with 3 primary GAD patients with secondary PDA. The efficacy of the treatment was evaluated with…
ERIC Educational Resources Information Center
Sims, Wesley A.; Riley-Tillman, Chris; Cohen, Daniel R.
2017-01-01
This study examined the treatment sensitivity of "Direct Behavior Rating-Single Item Scales" (DBR-SIS) in response to an evidence-based intervention delivered in a single-case, multiple-baseline design. DBR-SIS was used as a formative assessment in conjunction with a frequently used intervention in schools, a Daily Behavior Report Card…
ERIC Educational Resources Information Center
Akinlar, Aylin; Dogan, Suleyman
2017-01-01
Purpose: Upon inspection of Turkish national programs, it is seen that today they incorporate more universal values and principles such as democracy and pluralism. In order to design systems and curricula for multicultural societies, it is of great importance to thoroughly understand the phenomenon of multicultural education in minority and public…
Multiple case studies of STEM teachers' orientations to science teaching through engineering design
NASA Astrophysics Data System (ADS)
Rupp, Madeline
The following master's thesis is composed of two manuscripts describing STEM teachers' orientations to science teaching through engineering within the context of the Science Learning through Engineering Design (SLED) partnership. The framework guiding both studies was science teaching orientations, a component of pedagogical content knowledge. Data were collected via semi-structured interviews, multi-day classroom observations, pre- and post-observation interviews, implementation plans, and written reflections. Data sources were analyzed to generate two orientations to science teaching through engineering design for each participant. The first manuscript illustrates a single case study conducted with a sixth grade STEM teacher. Results of this study revealed a detailed picture of the teacher's goals, practices, assessments, and general views when teaching science through engineering design. Common themes across the teacher's instruction were used to characterize her orientations to science teaching through engineering design. Overall, the teacher's orientations showed a shift in her practice from didactic to student-centered methods of teaching as a result of integrating engineering design-based curriculum. The second manuscript describes a comparative case study of two sixth grade SLED participants. Results of this study revealed more complex and diverse relationships between the teachers' orientations to teaching science through engineering design and their instruction. Participants' orientations served as filters for instruction, guided by their divergent purposes for science teaching. Furthermore, their orientations and resulting implementation were developed from knowledge gained in teacher education, implying that teacher educators and researchers can use this framework to learn more about how teachers' knowledge is used to integrate engineering and science practices in the K-12 classroom.
Case analysis online: a strategic management case model for the health industry.
Walsh, Anne; Bearden, Eithne
2004-01-01
Despite the plethora of methods and tools available to support strategic management, the challenge for health executives in the next century will relate to their ability to access and interpret data from multiple and intricate communication networks. Integrated digital networks and satellite systems will expand the scope and ease of sharing information between business divisions, and networked systems will facilitate the use of virtual case discussions across universities. While the internet is frequently used to support clinical decisions in the healthcare industry, few executives rely upon the internetfor strategic analysis. Although electronic technologies can easily synthesize data from multiple information channels, research as well as technical issues may deter their application in strategic analysis. As digital models transform access to information, online models may become increasingly relevant in designing strategic solutions. While there are various pedagogical models available to support the strategic management process, this framework was designed to enhance strategic analysis through the application of technology and electronic research. A strategic analysis framework, which incorporated internet research and case analysis in a strategic managementcourse, is described alongwith design and application issues that emerged during the case analysis process.
Adaptive subdomain modeling: A multi-analysis technique for ocean circulation models
NASA Astrophysics Data System (ADS)
Altuntas, Alper; Baugh, John
2017-07-01
Many coastal and ocean processes of interest operate over large temporal and geographical scales and require a substantial amount of computational resources, particularly when engineering design and failure scenarios are also considered. This study presents an adaptive multi-analysis technique that improves the efficiency of these computations when multiple alternatives are being simulated. The technique, called adaptive subdomain modeling, concurrently analyzes any number of child domains, with each instance corresponding to a unique design or failure scenario, in addition to a full-scale parent domain providing the boundary conditions for its children. To contain the altered hydrodynamics originating from the modifications, the spatial extent of each child domain is adaptively adjusted during runtime depending on the response of the model. The technique is incorporated in ADCIRC++, a re-implementation of the popular ADCIRC ocean circulation model with an updated software architecture designed to facilitate this adaptive behavior and to utilize concurrent executions of multiple domains. The results of our case studies confirm that the method substantially reduces computational effort while maintaining accuracy.
Effects of Acupuncture on Gait of Patients with Multiple Sclerosis.
Criado, Maria Begoña; Santos, Maria João; Machado, Jorge; Gonçalves, Arminda Manuela; Greten, Henry Johannes
2017-11-01
Multiple sclerosis is considered a complex and heterogeneous disease. Approximately 85% of patients with multiple sclerosis indicate impaired gait as one of the major limitations in their daily life. Acupuncture studies found a reduction of spasticity and improvement of fatigue and imbalance in patients with multiple sclerosis, but there is a lack of studies regarding gait. We designed a study of acupuncture treatment, according to the Heidelberg model of Traditional Chinese Medicine (TCM), to investigate if acupuncture can be a useful therapeutic strategy in patients with gait impairment in multiple sclerosis of relapsing-remitting type. The sample consisted of 20 individuals with diagnosis of multiple sclerosis of relapsing-remitting type. Gait impairment was evaluated by the 25-foot walk test. The results showed differences in time to walk 25 feet following true acupuncture. In contrast, there was no difference in time to walk 25 feet following sham acupuncture. When using true acupuncture, 95% of cases showed an improvement in 25-foot walk test, compared with 45% when sham acupuncture was done. Our study protocol provides evidence that acupuncture treatment can be an attractive option for patients with multiple sclerosis, with gait impairment.
Scheduling optimization of design stream line for production research and development projects
NASA Astrophysics Data System (ADS)
Liu, Qinming; Geng, Xiuli; Dong, Ming; Lv, Wenyuan; Ye, Chunming
2017-05-01
In a development project, efficient design stream line scheduling is difficult and important owing to large design imprecision and the differences in the skills and skill levels of employees. The relative skill levels of employees are denoted as fuzzy numbers. Multiple execution modes are generated by scheduling different employees for design tasks. An optimization model of a design stream line scheduling problem is proposed with the constraints of multiple executive modes, multi-skilled employees and precedence. The model considers the parallel design of multiple projects, different skills of employees, flexible multi-skilled employees and resource constraints. The objective function is to minimize the duration and tardiness of the project. Moreover, a two-dimensional particle swarm algorithm is used to find the optimal solution. To illustrate the validity of the proposed method, a case is examined in this article, and the results support the feasibility and effectiveness of the proposed model and algorithm.
A study of pilot modeling in multi-controller tasks
NASA Technical Reports Server (NTRS)
Whitbeck, R. F.; Knight, J. R.
1972-01-01
A modeling approach, which utilizes a matrix of transfer functions to describe the human pilot in multiple input, multiple output control situations, is studied. The approach used was to extend a well established scalar Wiener-Hopf minimization technique to the matrix case and then study, via a series of experiments, the data requirements when only finite record lengths are available. One of these experiments was a two-controller roll tracking experiment designed to force the pilot to use rudder in order to coordinate and reduce the effects of aileron yaw. One model was computed for the case where the signals used to generate the spectral matrix are error and bank angle while another model was computed for the case where error and yaw angle are the inputs. Several anomalies were observed to be present in the experimental data. These are defined by the descriptive terms roll up, break up, and roll down. Due to these algorithm induced anomalies, the frequency band over which reliable estimates of power spectra can be achieved is considerably less than predicted by the sampling theorem.
NASA Astrophysics Data System (ADS)
Nicholas, K. A.; Feola, G.; Lerner, A. M.; Jain, M.; Montefrio, M.
2013-12-01
The global challenge of sustaining agricultural livelihoods and yields in the face of growing populations and increasing climate change is the topic of intense research. The role of on-the-ground decision-making by individual farmers actually producing food, fuel, and fiber is often studied in individual cases to determine its environmental, economic, and social effects. However, there are few efforts to link across studies in a way that provides opportunities to better understand empirical farmer behavior, design effective policies, and be able to aggregate from case studies to a broader scale. Here we synthesize existing literature to identify four general factors affecting farmer decision-making: local technical and socio-cultural contexts; actors and institutions involved in decision-making; multiple stressors at broader scales; and the temporal gradient of decision-making. We use these factors to compare five cases that illustrate agricultural decision-making and its impacts: cotton and castor farming in Gujarat, India; swidden cultivation of upland rice in the Philippines; potato cultivation in Andean Colombia; winegrowing in Northern California; and maize production in peri-urban central Mexico. These cases span a geographic and economic range of production systems, but we find that we are able to make valid comparisons and draw lessons common across all cases by using the four factors as an organizing principle. We also find that our understanding of why farmers make the decisions they do changes if we neglect to examine even one of the four general factors guiding decision-making. This suggests that these four factors are important to understanding farmer decision-making, and can be used to guide the design and interpretation of future studies, as well as be the subject of further research in and of themselves to promote an agricultural system that is resilient to climate and other global environmental changes.
ERIC Educational Resources Information Center
Gallagher, Pádraig
2015-01-01
This research looks at the role of graduate placement programmes in bridging the gap between higher education and the small- and medium-sized enterprise (SME) sector. The research design and methodology used in this study was exploratory, in-depth and qualitative in nature. The research took the form of a multiple case study and focused on seven…
Robust design of configurations and parameters of adaptable products
NASA Astrophysics Data System (ADS)
Zhang, Jian; Chen, Yongliang; Xue, Deyi; Gu, Peihua
2014-03-01
An adaptable product can satisfy different customer requirements by changing its configuration and parameter values during the operation stage. Design of adaptable products aims at reducing the environment impact through replacement of multiple different products with single adaptable ones. Due to the complex architecture, multiple functional requirements, and changes of product configurations and parameter values in operation, impact of uncertainties to the functional performance measures needs to be considered in design of adaptable products. In this paper, a robust design approach is introduced to identify the optimal design configuration and parameters of an adaptable product whose functional performance measures are the least sensitive to uncertainties. An adaptable product in this paper is modeled by both configurations and parameters. At the configuration level, methods to model different product configuration candidates in design and different product configuration states in operation to satisfy design requirements are introduced. At the parameter level, four types of product/operating parameters and relations among these parameters are discussed. A two-level optimization approach is developed to identify the optimal design configuration and its parameter values of the adaptable product. A case study is implemented to illustrate the effectiveness of the newly developed robust adaptable design method.
Thermal Modeling of the Injection of Standard and Thermally Insulated Cored Wire
NASA Astrophysics Data System (ADS)
Castro-Cedeno, E.-I.; Jardy, A.; Carré, A.; Gerardin, S.; Bellot, J. P.
2017-12-01
Cored wire injection is a widespread method used to perform alloying additions during ferrous and non-ferrous liquid metal treatment. The wire consists of a metal casing that is tightly wrapped around a core of material; the casing delays the release of the material as the wire is immersed into the melt. This method of addition presents advantages such as higher repeatability and yield of cored material with respect to bulk additions. Experimental and numerical work has been performed by several authors on the subject of alloy additions, spherical and cylindrical geometries being mainly considered. Surprisingly this has not been the case for cored wire, where the reported experimental or numerical studies are scarce. This work presents a 1-D finite volume numerical model aimed for the simulation of the thermal phenomena which occurs when the wire is injected into a liquid metal bath. It is currently being used as a design tool for the conception of new types of cored wire. A parametric study on the effect of injection velocity and steel casing thickness for an Al cored wire immersed into a steel melt at 1863 K (1590 °C) is presented. The standard single casing wire is further compared against a wire with multiple casings. Numerical results show that over a certain range of injection velocities, the core contents' release is delayed in the multiple casing when compared to a single casing wire.
ERIC Educational Resources Information Center
Aßmann, Christian; Würbach, Ariane; Goßmann, Solange; Geissler, Ferdinand; Bela, Anika
2017-01-01
Large-scale surveys typically exhibit data structures characterized by rich mutual dependencies between surveyed variables and individual-specific skip patterns. Despite high efforts in fieldwork and questionnaire design, missing values inevitably occur. One approach for handling missing values is to provide multiply imputed data sets, thus…
ERIC Educational Resources Information Center
Rock, Marcia L.; Thead, Beth K.
2007-01-01
In this study, using a single-case multiple-treatment reversal (A-B-A-B-C) research design, we replicated and extended previous strategic self-monitoring research by teaching five students, with and without disabilities, to use ACT-REACT to increase their academic engagement, productivity, and accuracy across new and previously learned math…
ERIC Educational Resources Information Center
Buggey, Tom
2012-01-01
Video Self-Modeling (VSM) provides individuals the opportunity to view themselves performing a task beyond their present functioning level through the careful editing of videos. In this study, a single-case multiple-baseline design was used to determine whether VSM would facilitate social initiations across three young children (M = 3 years 10…
Teaching Argumentative Writing to Teachers and Students: Effects of Professional Development
ERIC Educational Resources Information Center
Howell, Emily; Hunt-Barron, Sarah; Kaminski, Rebecca; Sanders, Rachel
2018-01-01
This multiple-case study design with embedded units of analysis examined a two-year professional development (PD) program in which two rural districts received at least 90 hours of PD. This PD was provided through an Investing in Innovation (i3) grant that the United States Department of Education awarded to the National Writing Project. Two of…
ERIC Educational Resources Information Center
Lavelli, Manuela; Fogel, Alan
2013-01-01
A microgenetic research design with a multiple case study method and a combination of quantitative and qualitative analyses was used to investigate interdyad differences in real-time dynamics and developmental change processes in mother-infant face-to-face communication over the first 3 months of life. Weekly observations of 24 mother-infant dyads…
From Scientists to Teachers: The Role of Student Epistemology in Lesson Plans of Career Switchers
ERIC Educational Resources Information Center
Burton, Erin Peters; Burton, Stephen
2016-01-01
Professional scientists who pursue a teaching credential bring a great deal of background to students in a classroom, but they may have barriers to the ways they portray the field of science. This study used a multiple-case replication design to determine the role of epistemology in lesson plans of seven scientists becoming teachers. Data sources…
ERIC Educational Resources Information Center
Borba, Marcelo; Confrey, Jere
Function Probe is a multi-representational software for Apple Macintosh computers. It was designed to allow students to approach problems in different ways and/or use different representations. This case study describes a 16-year-old student as he creates a path among a variety of representations of transformations of functions while using the…
ERIC Educational Resources Information Center
Ramsberger, Gail; Marie, Basem
2007-01-01
Purpose: This study examined the benefits of a self-administered, clinician-guided, computer-based, cued naming therapy. Results of intense and nonintense treatment schedules were compared. Method: A single-participant design with multiple baselines across behaviors and varied treatment intensity for 2 trained lists was replicated over 4…
Evaluating ICT Integration in Turkish K-12 Schools through Teachers' Views
ERIC Educational Resources Information Center
Aydin, Mehmet Kemal; Gürol, Mehmet; Vanderlinde, Ruben
2016-01-01
The current study aims to explore ICT integration in Turkish K-12 schools purposively selected as a representation of F@tih and non-F@tih public schools together with a private school. A convergent mixed methods design was employed with a multiple case strategy as such it will enable to make casewise comparisons. The quantitative data was…
ERIC Educational Resources Information Center
Nzuki, Charles Kyalo
2018-01-01
The effects of the Constituency Development Fund (CDF) and the Free Secondary Education Policy (FSEP) on access to secondary school education in Kenya's Yatta sub-county have not been adequately explored in available public policy literature. Hence, this qualitative multiple-case study was designed to understand the effects of the 2 policies on…
Management of Globally Distributed Software Development Projects in Multiple-Vendor Constellations
NASA Astrophysics Data System (ADS)
Schott, Katharina; Beck, Roman; Gregory, Robert Wayne
Global information systems development outsourcing is an apparent trend that is expected to continue in the foreseeable future. Thereby, IS-related services are not only increasingly provided from different geographical sites simultaneously but beyond that from multiple service providers based in different countries. The purpose of this paper is to understand how the involvement of multiple service providers affects the management of the globally distributed information systems development projects. As research on this topic is scarce, we applied an exploratory in-depth single-case study design as research approach. The case we analyzed comprises a global software development outsourcing project initiated by a German bank together with several globally distributed vendors. For data collection and data analysis we have adopted techniques suggested by the grounded theory method. Whereas the extant literature points out the increased management overhead associated with multi-sourcing, the analysis of our case suggests that the required effort for managing global outsourcing projects with multiple vendors depends among other things on the maturation level of the cooperation within the vendor portfolio. Furthermore, our data indicate that this interplay maturity is positively impacted through knowledge about the client that has been derived based on already existing client-vendor relationships. The paper concludes by offering theoretical and practical implications.
Ho, Lindsey A; Lange, Ethan M
2010-12-01
Genome-wide association (GWA) studies are a powerful approach for identifying novel genetic risk factors associated with human disease. A GWA study typically requires the inclusion of thousands of samples to have sufficient statistical power to detect single nucleotide polymorphisms that are associated with only modest increases in risk of disease given the heavy burden of a multiple test correction that is necessary to maintain valid statistical tests. Low statistical power and the high financial cost of performing a GWA study remains prohibitive for many scientific investigators anxious to perform such a study using their own samples. A number of remedies have been suggested to increase statistical power and decrease cost, including the utilization of free publicly available genotype data and multi-stage genotyping designs. Herein, we compare the statistical power and relative costs of alternative association study designs that use cases and screened controls to study designs that are based only on, or additionally include, free public control genotype data. We describe a novel replication-based two-stage study design, which uses free public control genotype data in the first stage and follow-up genotype data on case-matched controls in the second stage that preserves many of the advantages inherent when using only an epidemiologically matched set of controls. Specifically, we show that our proposed two-stage design can substantially increase statistical power and decrease cost of performing a GWA study while controlling the type-I error rate that can be inflated when using public controls due to differences in ancestry and batch genotype effects.
Design of microarray experiments for genetical genomics studies.
Bueno Filho, Júlio S S; Gilmour, Steven G; Rosa, Guilherme J M
2006-10-01
Microarray experiments have been used recently in genetical genomics studies, as an additional tool to understand the genetic mechanisms governing variation in complex traits, such as for estimating heritabilities of mRNA transcript abundances, for mapping expression quantitative trait loci, and for inferring regulatory networks controlling gene expression. Several articles on the design of microarray experiments discuss situations in which treatment effects are assumed fixed and without any structure. In the case of two-color microarray platforms, several authors have studied reference and circular designs. Here, we discuss the optimal design of microarray experiments whose goals refer to specific genetic questions. Some examples are used to illustrate the choice of a design for comparing fixed, structured treatments, such as genotypic groups. Experiments targeting single genes or chromosomic regions (such as with transgene research) or multiple epistatic loci (such as within a selective phenotyping context) are discussed. In addition, microarray experiments in which treatments refer to families or to subjects (within family structures or complex pedigrees) are presented. In these cases treatments are more appropriately considered to be random effects, with specific covariance structures, in which the genetic goals relate to the estimation of genetic variances and the heritability of transcriptional abundances.
Hybrid PV/diesel solar power system design using multi-level factor analysis optimization
NASA Astrophysics Data System (ADS)
Drake, Joshua P.
Solar power systems represent a large area of interest across a spectrum of organizations at a global level. It was determined that a clear understanding of current state of the art software and design methods, as well as optimization methods, could be used to improve the design methodology. Solar power design literature was researched for an in depth understanding of solar power system design methods and algorithms. Multiple software packages for the design and optimization of solar power systems were analyzed for a critical understanding of their design workflow. In addition, several methods of optimization were studied, including brute force, Pareto analysis, Monte Carlo, linear and nonlinear programming, and multi-way factor analysis. Factor analysis was selected as the most efficient optimization method for engineering design as it applied to solar power system design. The solar power design algorithms, software work flow analysis, and factor analysis optimization were combined to develop a solar power system design optimization software package called FireDrake. This software was used for the design of multiple solar power systems in conjunction with an energy audit case study performed in seven Tibetan refugee camps located in Mainpat, India. A report of solar system designs for the camps, as well as a proposed schedule for future installations was generated. It was determined that there were several improvements that could be made to the state of the art in modern solar power system design, though the complexity of current applications is significant.
A Standardized Mean Difference Effect Size for Multiple Baseline Designs across Individuals
ERIC Educational Resources Information Center
Hedges, Larry V.; Pustejovsky, James E.; Shadish, William R.
2013-01-01
Single-case designs are a class of research methods for evaluating treatment effects by measuring outcomes repeatedly over time while systematically introducing different condition (e.g., treatment and control) to the same individual. The designs are used across fields such as behavior analysis, clinical psychology, special education, and…
Bagdasarov, Zhanna; Thiel, Chase E; Johnson, James F; Connelly, Shane; Harkrider, Lauren N; Devenport, Lynn D; Mumford, Michael D
2013-09-01
Cases have been employed across multiple disciplines, including ethics education, as effective pedagogical tools. However, the benefit of case-based learning in the ethics domain varies across cases, suggesting that not all cases are equal in terms of pedagogical value. Indeed, case content appears to influence the extent to which cases promote learning and transfer. Consistent with this argument, the current study explored the influences of contextual and personal factors embedded in case content on ethical decision-making. Cases were manipulated to include a clear description of the social context and the goals of the characters involved. Results indicated that social context, specifically the description of an autonomy-supportive environment, facilitated execution of sense making processes and resulted in greater decision ethicality. Implications for designing optimal cases and case-based training programs are discussed.
MetaRNA-Seq: An Interactive Tool to Browse and Annotate Metadata from RNA-Seq Studies.
Kumar, Pankaj; Halama, Anna; Hayat, Shahina; Billing, Anja M; Gupta, Manish; Yousri, Noha A; Smith, Gregory M; Suhre, Karsten
2015-01-01
The number of RNA-Seq studies has grown in recent years. The design of RNA-Seq studies varies from very simple (e.g., two-condition case-control) to very complicated (e.g., time series involving multiple samples at each time point with separate drug treatments). Most of these publically available RNA-Seq studies are deposited in NCBI databases, but their metadata are scattered throughout four different databases: Sequence Read Archive (SRA), Biosample, Bioprojects, and Gene Expression Omnibus (GEO). Although the NCBI web interface is able to provide all of the metadata information, it often requires significant effort to retrieve study- or project-level information by traversing through multiple hyperlinks and going to another page. Moreover, project- and study-level metadata lack manual or automatic curation by categories, such as disease type, time series, case-control, or replicate type, which are vital to comprehending any RNA-Seq study. Here we describe "MetaRNA-Seq," a new tool for interactively browsing, searching, and annotating RNA-Seq metadata with the capability of semiautomatic curation at the study level.
NASA Astrophysics Data System (ADS)
Kermish-Allen, Ruth
Traditional citizen science projects have been based on the scientific communities need to gather vast quantities of high quality data, neglecting to ask what the project participants get in return. How can participants be seen more as collaborative partners in citizen science projects? Online communities for citizen science are expanding rapidly, giving participants the opportunity to take part in a wide range of activities, from monitoring invasive species to identifying far-off galaxies. These communities can bring together the virtual and physical worlds in new ways that are egalitarian, collaborative, applied, localized and globalized to solve real environmental problems. There are a small number of citizen science projects that leverage the affordances of an online community to connect, engage, and empower participants to make local change happen. This multiple case study applies a conceptual framework rooted in sociocultural learning theory, Non-Hierarchical Online Learning Communities (NHOLCs), to three online citizen communities that have successfully fostered online collaboration and on-the-ground environmental actions. The purpose of the study is to identify the range and variation of the online and programmatic functions available in each project. The findings lead to recommendations for designing these innovative communities, specifically the technological and programmatic components of online citizen science communities that support environmental actions in our backyards.
ERIC Educational Resources Information Center
Docq, Françoise
2015-01-01
This case discusses the design, implementation, and regulation of a hybrid training program (60 credits over two years) organised by three business schools in Europe, and stretching over a five-year period. Following an incremental design process, the design team faced multiple challenges, from finding the added value of hybridization to choosing…
Zimmerman, Scott D; Lester Short, Glenda F; Hendrix, E Michael
2011-01-01
It remains unclear which classroom experiences, if any, foster critical think ability. We measured the effectiveness of interdisciplinary, case-based learning on the critical-thinking ability of graduate students enrolled in allied health care programs. We designed a voluntary classroom experience to examine the effectiveness of case studies used in an interdisciplinary setting to increase critical-thinking ability. Two groups of students were measured for their critical thinking ability using an online assessment both before and after their respective classroom experiences. One group of 14 graduate students from 4 different allied health care programs (interdisciplinary, ID) discussed complex interdisciplinary case studies and answered multiple-choice type questions formed around the cases. The second group was composed of graduate students (n = 28) from a single disciple enrolled in a clinical anatomy course (discipline specific, DS). They discussed complex case studies specific to their discipline and answered multiple-choice questions formed around the cases. There was no overall change in critical-thinking scores from the pre- to post-test in either group (delta scores: ID 1.5 ± 5.3, DS -1.7 ± 5.7). However, ID students scoring below the median on the pretest improved significantly (paired t-test, pre 50.7 ± 3.8, post 54.2 ± 1.7, p = 0.02). The interdisciplinary learning experience improved critical-thinking ability in students with the least proficiency. As case studies have long been used to advance deeper learning, these data provide evidence for a broader impact of cases when used in an interdisciplinary setting, especially for those students coming in with the least ability.
Sampling design considerations for demographic studies: a case of colonial seabirds
Kendall, William L.; Converse, Sarah J.; Doherty, Paul F.; Naughton, Maura B.; Anders, Angela; Hines, James E.; Flint, Elizabeth
2009-01-01
For the purposes of making many informed conservation decisions, the main goal for data collection is to assess population status and allow prediction of the consequences of candidate management actions. Reducing the bias and variance of estimates of population parameters reduces uncertainty in population status and projections, thereby reducing the overall uncertainty under which a population manager must make a decision. In capture-recapture studies, imperfect detection of individuals, unobservable life-history states, local movement outside study areas, and tag loss can cause bias or precision problems with estimates of population parameters. Furthermore, excessive disturbance to individuals during capture?recapture sampling may be of concern because disturbance may have demographic consequences. We address these problems using as an example a monitoring program for Black-footed Albatross (Phoebastria nigripes) and Laysan Albatross (Phoebastria immutabilis) nesting populations in the northwestern Hawaiian Islands. To mitigate these estimation problems, we describe a synergistic combination of sampling design and modeling approaches. Solutions include multiple capture periods per season and multistate, robust design statistical models, dead recoveries and incidental observations, telemetry and data loggers, buffer areas around study plots to neutralize the effect of local movements outside study plots, and double banding and statistical models that account for band loss. We also present a variation on the robust capture?recapture design and a corresponding statistical model that minimizes disturbance to individuals. For the albatross case study, this less invasive robust design was more time efficient and, when used in combination with a traditional robust design, reduced the standard error of detection probability by 14% with only two hours of additional effort in the field. These field techniques and associated modeling approaches are applicable to studies of most taxa being marked and in some cases have individually been applied to studies of birds, fish, herpetofauna, and mammals.
Pruijssers, Addy; van Meijel, Berno; Maaskant, Marian; Keeman, Noortje; van Achterberg, Theo
2016-07-01
People with intellectual disabilities often have a multitude of concurrent problems due to the combination of cognitive impairments, psychiatric disorders (particularly anxiety) and related challenging behaviours. Diagnoses in people with intellectual disabilities are complicated. This study evaluates the quality of the diagnoses and treatment plans after using a guideline that was developed to support professionals in their diagnostic tasks. A comparative multiple case study with an experimental and control condition, applying deductive analyses of diagnoses and treatment plans. The analyses revealed that the number of diagnostic statements and planned treatment actions in the experimental group was significantly larger and more differentiated than in the control condition. In the control group, consequential harm and protective factors were hardly mentioned in diagnoses and treatment plans. Working with the 'Diagnostic Guideline for Anxiety and CB' leads to improved diagnoses and treatment plans compared with care as usual. © 2015 John Wiley & Sons Ltd.
Breet, Elsie; Bantjes, Jason
2017-12-01
Few qualitative studies have explored the relationship between substance use and self-harm. We employed a multiple-case study research design to analyze data from 80 patients who were admitted to a hospital in South Africa following self-harm. Our analysis revealed, from the perspective of patients, a number of distinct ways in which substance use is implicated in self-harm. Some patients reported that substance intoxication resulted in poor decision making and impulsivity, which led to self-harm. Others said substance use facilitated their self-harm. Some participants detailed how in the past their chronic substance use had served an adaptive function helping them to cope with distress, but more recently, this coping mechanism had failed which precipitated their self-harm. Some participants reported that substance use by someone else triggered their self-harm. Findings suggest that there are multiple pathways and a host of variables which mediate the relationship between substance use and self-harm.
Two-Stage Fan I: Aerodynamic and Mechanical Design
NASA Technical Reports Server (NTRS)
Messenger, H. E.; Kennedy, E. E.
1972-01-01
A two-stage, highly-loaded fan was designed to deliver an overall pressure ratio of 2.8 with an adiabatic efficiency of 83.9 percent. At the first rotor inlet, design flow per unit annulus area is 42 lbm/sec/sq ft (205 kg/sec/sq m), hub/tip ratio is 0.4 with a tip diameter of 31 inches (0.787 m), and design tip speed is 1450 ft/sec (441.96 m/sec). Other features include use of multiple-circular-arc airfoils, resettable stators, and split casings over the rotor tip sections for casing treatment tests.
Joint Smoothed l₀-Norm DOA Estimation Algorithm for Multiple Measurement Vectors in MIMO Radar.
Liu, Jing; Zhou, Weidong; Juwono, Filbert H
2017-05-08
Direction-of-arrival (DOA) estimation is usually confronted with a multiple measurement vector (MMV) case. In this paper, a novel fast sparse DOA estimation algorithm, named the joint smoothed l 0 -norm algorithm, is proposed for multiple measurement vectors in multiple-input multiple-output (MIMO) radar. To eliminate the white or colored Gaussian noises, the new method first obtains a low-complexity high-order cumulants based data matrix. Then, the proposed algorithm designs a joint smoothed function tailored for the MMV case, based on which joint smoothed l 0 -norm sparse representation framework is constructed. Finally, for the MMV-based joint smoothed function, the corresponding gradient-based sparse signal reconstruction is designed, thus the DOA estimation can be achieved. The proposed method is a fast sparse representation algorithm, which can solve the MMV problem and perform well for both white and colored Gaussian noises. The proposed joint algorithm is about two orders of magnitude faster than the l 1 -norm minimization based methods, such as l 1 -SVD (singular value decomposition), RV (real-valued) l 1 -SVD and RV l 1 -SRACV (sparse representation array covariance vectors), and achieves better DOA estimation performance.
Jacob, Robin; Somers, Marie-Andree; Zhu, Pei; Bloom, Howard
2016-06-01
In this article, we examine whether a well-executed comparative interrupted time series (CITS) design can produce valid inferences about the effectiveness of a school-level intervention. This article also explores the trade-off between bias reduction and precision loss across different methods of selecting comparison groups for the CITS design and assesses whether choosing matched comparison schools based only on preintervention test scores is sufficient to produce internally valid impact estimates. We conduct a validation study of the CITS design based on the federal Reading First program as implemented in one state using results from a regression discontinuity design as a causal benchmark. Our results contribute to the growing base of evidence regarding the validity of nonexperimental designs. We demonstrate that the CITS design can, in our example, produce internally valid estimates of program impacts when multiple years of preintervention outcome data (test scores in the present case) are available and when a set of reasonable criteria are used to select comparison organizations (schools in the present case). © The Author(s) 2016.
Interventions aimed at improving the ability to use everyday technology in work after brain injury.
Kassberg, Ann-Charlotte; Prellwitz, Maria; Malinowsky, Camilla; Larsson-Lund, Maria
2016-01-01
The aim of this study was to explore and describe how client-centred occupational therapy interventions may support and improve the ability to use everyday technology (ET) in work tasks in people with acquired brain injury (ABI). A qualitative, descriptive multiple-case study was designed, and occupation-based interventions were provided to three working-age participants with ABI. Multiple sources were used to collect data throughout the three intervention processes, including assessments, field notes, and interviews. The Canadian Occupational Performance Measure and the Management of Everyday Technology Assessment were administered before the interventions, after the interventions and at a follow-up session 2-3 months subsequent to the interventions. The three intervention processes initially consisted of similar actions, but subsequently the actions took on a different focus and intensity for each case. All of the goals in each of the three case processes were achieved, and both perceived and observed abilities to use ET in work tasks improved. Client-centred occupational therapy interventions might have the potential to improve the ability to use ET in work tasks in people with ABI.
Fathauer, L; Meek, J.
2012-01-01
Background Clinician compliance with clinical guidelines in the treatment of patients with Hepatitis C (HCV) has been reported to be as low as 18.5%. Treatment is complex and patient compliance is often inconsistent thus, active clinician surveillance and support is essential to successful outcomes. A clinical decision support system (CDSS) embedded within an electronic health record can provide reminders, summarize key data, and facilitate coordination of care. To date, the literature is bereft of information describing the implementation and evaluation of a CDSS to support HCV treatment. Objective The purpose of this case report is to describe the design, implementation, and initial evaluation of an HCV-specific CDSS while piloting data collection metrics and methods to be used in a larger study across multiple practices. Methods The case report describes the design and implementation processes with preliminary reporting on impact of the CDSS on quality indicator completion by comparing the pre-CDSS group to the post-CDSS group. Results The CDSS was successfully designed and implemented using an iterative, collaborative process. Pilot testing of the clinical outcomes of the CDSS revealed high rates of quality indicator completion in both the pre- and post-CDSS; although the post-CDSS group received a higher frequency of reminders (4.25 per patient) than the pre-CDSS group (.25 per patient). Conclusions This case report documents the processes used to successfully design and implement an HCV CDSS. While the small sample size precludes generalizability of findings, results did positively demonstrate the feasibility of comparing quality indicator completion rates pre-CDSS and post-CDSS. It is recommended that future studies include a larger sample size across multiple providers with expanded outcomes measures related to patient outcomes, staff satisfaction with the CDSS, and time studies to evaluate efficiency and cost effectiveness of the CDSS. PMID:23646082
Bateman, James; Allen, Maggie E; Kidd, Jane; Parsons, Nick; Davies, David
2012-08-01
Virtual Patients (VPs) are web-based representations of realistic clinical cases. They are proposed as being an optimal method for teaching clinical reasoning skills. International standards exist which define precisely what constitutes a VP. There are multiple design possibilities for VPs, however there is little formal evidence to support individual design features. The purpose of this trial is to explore the effect of two different potentially important design features on clinical reasoning skills and the student experience. These are the branching case pathways (present or absent) and structured clinical reasoning feedback (present or absent). This is a multi-centre randomised 2 x 2 factorial design study evaluating two independent variables of VP design, branching (present or absent), and structured clinical reasoning feedback (present or absent).The study will be carried out in medical student volunteers in one year group from three university medical schools in the United Kingdom, Warwick, Keele and Birmingham. There are four core musculoskeletal topics. Each case can be designed in four different ways, equating to 16 VPs required for the research. Students will be randomised to four groups, completing the four VP topics in the same order, but with each group exposed to a different VP design sequentially. All students will be exposed to the four designs. Primary outcomes are performance for each case design in a standardized fifteen item clinical reasoning assessment, integrated into each VP, which is identical for each topic. Additionally a 15-item self-reported evaluation is completed for each VP, based on a widely used EViP tool. Student patterns of use of the VPs will be recorded.In one centre, formative clinical and examination performance will be recorded, along with a self reported pre and post-intervention reasoning score, the DTI. Our power calculations indicate a sample size of 112 is required for both primary outcomes. This trial will provide robust evidence to support the effectiveness of different designs of virtual patients, based on student performance and evaluation. The cases and all learning materials will be open access and available on a Creative Commons Attribution-Share-Alike license.
ERIC Educational Resources Information Center
Nielsen, Brita Fladvad; Rodrigues Santos, Ana Laura
2013-01-01
A "humanitarian market" for off-grid renewable energy technologies for displaced populations in remote areas has emerged. Within this market, there are multiple stakeholder agendas. End-user needs and sustainable development goals are currently not considered through the customer-enterprise relationship and the applied product and…
Developing Teacher Leadership in Singapore: Multiple Pathways for Differentiated Journeys
ERIC Educational Resources Information Center
Goodwin, A. Lin; Low, Ee Ling; Ng, Pak Tee
2015-01-01
In this article, we examine quality teachers through teacher leadership development. Using Singapore as an illustrative case, we describe the redefinition of the teaching profession to include deliberate structures and multiple pathways designed to nurture teacher leaders, and the role of teacher leaders in supporting education reform. We go on to…
A decoupled approach to filter design for stochastic systems
NASA Astrophysics Data System (ADS)
Barbata, A.; Zasadzinski, M.; Ali, H. Souley; Messaoud, H.
2016-08-01
This paper presents a new theorem to guarantee the almost sure exponential stability for a class of stochastic triangular systems by studying only the stability of each diagonal subsystems. This result allows to solve the filtering problem of the stochastic systems with multiplicative noises by using the almost sure exponential stability concept. Two kinds of observers are treated: the full-order and reduced-order cases.
Study of solution procedures for nonlinear structural equations
NASA Technical Reports Server (NTRS)
Young, C. T., II; Jones, R. F., Jr.
1980-01-01
A method for the redution of the cost of solution of large nonlinear structural equations was developed. Verification was made using the MARC-STRUC structure finite element program with test cases involving single and multiple degrees of freedom for static geometric nonlinearities. The method developed was designed to exist within the envelope of accuracy and convergence characteristic of the particular finite element methodology used.
ERIC Educational Resources Information Center
Söderhjelm, Teresa; Björklund, Christina; Sandahl, Christer; Bolander-Laksov, Klara
2018-01-01
Demands on academic leadership are increasing, which raises the need for leadership training. This article describes development and implementation of a group training intervention in academic leadership at a departmental level. Little systematic research has addressed the question of what forms of leadership training are associated with…
ERIC Educational Resources Information Center
Akin, Fatma Nur; Uzuntiryaki-Kondakci, Esen
2018-01-01
We examined the interactions among pedagogical content knowledge (PCK) components of novice and experienced chemistry teachers in teaching reaction rate and chemical equilibrium topics in this qualitative multiple-case design study. For this aim, three chemistry teachers who had different levels of teaching experience in chemistry teaching were…
ERIC Educational Resources Information Center
DeSchryver, Michael
2012-01-01
This dissertation utilized a multiple case study design to explore how advanced learners synthesize information about ill-structured topics when reading-to-learn and reading-to-do on the Web. Eight graduate students provided data in the form of think-alouds, interviews, screen video, digital trails, and task artifacts. Data analysis was based on…
Belonging, Identity and Third Culture Kids: Life Histories of Former International School Students
ERIC Educational Resources Information Center
Fail, Helen; Thompson, Jeff; Walker, George
2004-01-01
This article is based on a multiple case study which examines the lives of a group of 11 former international school students who all attended an international school between 20 and 50 years ago. The research design was based on a review of the literature on third culture kids and adult third culture kids, covering emotional and relational issues…
ERIC Educational Resources Information Center
Pennington, Robert; Koehler, Mallory
2017-01-01
There is limited research on teaching narrative writing skills to students with moderate to severe intellectual disability. In the current study, we used a multiple probe across participants single case design to evaluate the effects of an intervention package comprised of modeling, story templates, and self-graphing, on the inclusion of story…
ERIC Educational Resources Information Center
Wilson, Duane
2014-01-01
In response to a charge from the library administration, the Circulation Committee of the Harold B. Lee Library at Brigham Young University designed and implemented a thorough assessment of circulation policies. Using multiple assessment methods including surveys, focus groups, and statistical analysis, the committee determined that the…
Local search heuristic for the discrete leader-follower problem with multiple follower objectives
NASA Astrophysics Data System (ADS)
Kochetov, Yury; Alekseeva, Ekaterina; Mezmaz, Mohand
2016-10-01
We study a discrete bilevel problem, called as well as leader-follower problem, with multiple objectives at the lower level. It is assumed that constraints at the upper level can include variables of both levels. For such ill-posed problem we define feasible and optimal solutions for pessimistic case. A central point of this work is a two stage method to get a feasible solution under the pessimistic case, given a leader decision. The target of the first stage is a follower solution that violates the leader constraints. The target of the second stage is a pessimistic feasible solution. Each stage calls a heuristic and a solver for a series of particular mixed integer programs. The method is integrated inside a local search based heuristic that is designed to find near-optimal leader solutions.
DeSantis, Christopher J; Skrabalak, Sara E
2014-05-25
Au/Pd octopods with hollow, cubic interiors and Oh symmetry were synthesized for the first time by etching core@shell Pd@Au/Pd octopods to selectively remove their Pd interiors. Integration of multiple architectural features - in this case branching symmetry, composition, and interior design - into one nanostructure provides design strategies to new plasmonic colloids.
Thermal Control Subsystem Design for the Avionics of a Space Station Payload
NASA Technical Reports Server (NTRS)
Moran, Matthew E.
1996-01-01
A case study of the thermal control subsystem development for a space based payload is presented from the concept stage through preliminary design. This payload, the Space Acceleration Measurement System 2 (SAMS-2), will measure the acceleration environment at select locations within the International Space Station. Its thermal control subsystem must maintain component temperatures within an acceptable range over a 10 year life span, while restricting accessible surfaces to touch temperature limits and insuring fail safe conditions in the event of loss of cooling. In addition to these primary design objectives, system level requirements and constraints are imposed on the payload, many of which are driven by multidisciplinary issues. Blending these issues into the overall system design required concurrent design sessions with the project team, iterative conceptual design layouts, thermal analysis and modeling, and hardware testing. Multiple tradeoff studies were also performed to investigate the many options which surfaced during the development cycle.
Houghton, Catherine E; Casey, Dympna; Shaw, David; Murphy, Kathy
2012-08-01
The Clinical Skills Laboratory has become an essential structure in nurse education and several benefits of its use have been identified. However, the literature identifies the need to examine the transferability of skills learned there into the reality of practice. This research explored the role of the Clinical Skills Laboratory in preparing nursing students for the real world of practice. This paper focuses specifically on the perceptions of the teaching and assessment strategies employed there. Qualitative multiple case study design. Five case study sites. Interviewees (n=58) included academic staff, clinical staff and nursing students. Semi-structured interviews. The Clinical Skills Laboratory can provide a pathway to practice and its authenticity is significant. Teaching strategies need to incorporate communication as well as psychomotor skills. Including audio-visual recording into assessment strategies is beneficial. Effective relationships between education institutions and clinical settings are needed to enhance the transferability of the skills learned. The Clinical Skills Laboratory should provide an authentic learning environment, with the appropriate use of teaching strategies. It is crucial that effective links between educators and clinical staff are established and maintained. Copyright © 2011 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Wheeler, Christopher
This study focused on how physics teachers develop and implement activities that promote creative thinking strategies in the standards based physics classroom. A particular focus was placed on every day or little "c", creativity, which can be taught in the high school classroom. The study utilized a multiple case study design, which allows for in-depth study in a variety of settings. Four participants from various high schools were identified utilizing administrator recommendations. Data were then collected via interviews, observations, and documents. The data were coded and analyzed for emerging themes. The themes were then merged to determine findings to the stated research questions. The research demonstrated the importance of modifying activities for student interest and understanding through effective use of scientific inquiry. The past experiences and professional development of the participants served as a vital piece to the development of their educational pedagogy especially concerning inquiry and questioning strategies. It was also established that an unstructured, positive classroom environment is a vital aspect of teaching while supporting creative thinking skills.
Building evaluation capacity in Ontario's public health units: promising practices and strategies.
Bourgeois, I; Simmons, L; Buetti, D
2018-06-01
This article presents the findings of a project focusing on building evaluation capacity in 10 Ontario public health units. The study sought to identify effective strategies that lead to increased evaluation capacity in the participating organizations. This study used a qualitative, multiple case research design. An action research methodology was used to design customized evaluation capacity building (ECB) strategies for each participating organization, based on its specific context and needs. This methodological approach also enabled monitoring and assessment of each strategy, based on a common set of reporting templates. A multiple case study was used to analyze the findings from the 10 participating organizations and derive higher level findings. The main findings of the study show that most of the strategies used to increase evaluation capacity in public health units are promising, especially those focusing on developing the knowledge, skills, and attitudes of health unit staff and managers. Facilitators to ECB strategies were the engagement of all staff members, the support of leadership, and the existence of organizational tools and infrastructure to support evaluation. It is also essential to recognize that ECB takes time and resources to be successful. The design and implementation of ECB strategies should be based on organizational needs. These can be assessed using a standardized instrument, as well as interviews and staff surveys. The implementation of a multicomponent approach (i.e. several strategies implemented simultaneously) is also linked to better ECB outcomes in organizations. Copyright © 2018 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Wu, Shiau-Jiun; Lu, Po-Liang; Chen, Yen-Hsu; Pan, Hui-Juan; Feng, Ming-Chu
2011-12-01
The Taiwan government currently promotes a case management approach to tuberculosis (TB) treatment to address the growing number of TB and multiple drug-resistant TB cases in Taiwan. The approach aims to improve medical follow-up and monitor quality of care. The efficacy of this case management approach has yet to be evaluated. The current study was designed to evaluate the effect of individualized case manager counseling on TB patient disease knowledge, attitudes, and behavioral intention. This study employed a one-group pretest-posttest quasi-experimental design. Participants first answered an initial questionnaire survey including three structured scales that addressed, respectively, the facets of disease knowledge, attitudes, and behavioral intention. TB case managers then delivered two- stage counseling to participants based on assessed individual needs and outstanding issues identified in questionnaire answers. A second questionnaire survey was administered 30~42 days after the intervention. Data on a total of 96 TB patients were collected. Key study findings were (1) individualized counseling significantly improved TB patient disease knowledge (p < .001) and (2) TB patient attitudes correlated significantly and positively with behavior intention (p < .001). Individualized counseling provided during the early stages of TB helps elevate patient awareness of the importance of treatment, enhances compliance and increases the cure rate.
Reconfigurable intelligent sensors for health monitoring: a case study of pulse oximeter sensor.
Jovanov, E; Milenkovic, A; Basham, S; Clark, D; Kelley, D
2004-01-01
Design of low-cost, miniature, lightweight, ultra low-power, intelligent sensors capable of customization and seamless integration into a body area network for health monitoring applications presents one of the most challenging tasks for system designers. To answer this challenge we propose a reconfigurable intelligent sensor platform featuring a low-power microcontroller, a low-power programmable logic device, a communication interface, and a signal conditioning circuit. The proposed solution promises a cost-effective, flexible platform that allows easy customization, run-time reconfiguration, and energy-efficient computation and communication. The development of a common platform for multiple physical sensors and a repository of both software procedures and soft intellectual property cores for hardware acceleration will increase reuse and alleviate costs of transition to a new generation of sensors. As a case study, we present an implementation of a reconfigurable pulse oximeter sensor.
Yaogo, Maurice; Zongo, Sylvie; Somé, Paul‐André; Turcotte‐Tremblay, Anne‐Marie
2017-01-01
Abstract To improve health services' quantity and quality, African countries are increasingly engaging in performance‐based financing (PBF) interventions. Studies to understand their implementation in francophone West Africa are rare. This study analysed PBF implementation in Burkina Faso 12 months post‐launch in late 2014. The design was a multiple and contrasted case study involving 18 cases (health centres). Empirical data were collected from observations, informal (n = 224) and formal (n = 459) interviews, and documents. Outside the circle of persons trained in PBF, few in the community had knowledge of it. In some health centres, the fact that staff were receiving bonuses was intentionally not announced to populations and community leaders. Most local actors thought PBF was just another project, but the majority appreciated it. There were significant delays in setting up agencies for performance monitoring, auditing, and contracting, as well as in the payment. The first audits led rapidly to coping strategies among health workers and occasionally to some staging beforehand. No community‐based audits had yet been done. Distribution of bonuses varied from one centre to another. This study shows the importance of understanding the implementation of public health interventions in Africa and of uncovering coping strategies. PMID:28671285
Equity in Reform: Case Studies of Five Middle Schools Involved in Systemic Reform
NASA Astrophysics Data System (ADS)
Kahle, Jane Butler; Kelly, Mary Kay
Science and mathematics education reform documents of the last decade have called for improved teaching and learning for all children. To overcome inequalities, a systemic approach to reform has been adopted. The case studies synthesized in this analysis arc part of a larger effort to reform science and mathematics education systemically and assess the progress of systemic reform. The purpose of this study was to assess the progress toward achieving equitable systemic reform in five middle schools. A multiple-case study design was used, and qualitative data were collected. Kahle's Equity Metric was used to analyze the schools' progress toward achieving equitable systemic reform of mathematics and science. Two results occurred: Various equity issues were identified in the five case studies, and the metric proved efficacious in identifying barriers to or facilitators of equitable reform in the schools. Overall, the study illustrates how schools might assess their commitments to providing high-quality science and mathematics education to all students.
The Caterpillar Game: A Classroom Management System
ERIC Educational Resources Information Center
Floress, Margaret T.; Rock, Angela L.; Hailemariam, Assegedech
2017-01-01
A single-case experimental design was used to evaluate the effects of the Caterpillar Game, a classroom management system, on disruptive behavior in a general education first grade classroom. A multiple baseline design across settings was used to evaluate changes in student disruptive behavior and teacher praise. When the Caterpillar Game was…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-10
... uses multiple measures, that, in the case of teachers, may include observations for determining teacher...) training designed to improve the ability of teachers, supervisors, counselors, parents, community members... Effectiveness and Distribution of Effective Teachers or Principals. Projects that are designed to address the...
A Pilot Study to Examine Maturation of Body Temperature Control in Preterm Infants
Knobel, Robin B.; Levy, Janet; Katz, Laurence; Guenther, Bob; Holditch-Davis, Diane
2013-01-01
Objective To test instrumentation and develop analytic models to use in a larger study to examine developmental trajectories of body temperature and peripheral perfusion from birth in extremely low birth weight (EBLW) infants. Design A case study design. Setting The study took place in a level four neonatal intensive care unit (NICU) in North Carolina. Participants Four ELBW infants, less than 29 weeks gestational age at birth. Methods Physiologic data were measured every minute for the first 5 days of life: peripheral perfusion using perfusion index by Masimo and body temperature using thermistors. Body temperature was also measured using infrared thermal imaging. Stimulation and care events were recorded over the first 5 days using video which was coded with Noldus Observer software. Novel analytical models using the state space approach to time series analysis were developed to explore maturation of neural control over central and peripheral body temperature. Results/Conclusion Results from this pilot study confirmed the feasibility of using multiple instruments to measure temperature and perfusion in ELBW infants. This approach added rich data to our case study design and set a clinical context with which to interpret longitudinal physiological data. PMID:24004312
Malof, Jordan M.; Mazurowski, Maciej A.; Tourassi, Georgia D.
2013-01-01
Case selection is a useful approach for increasing the efficiency and performance of case-based classifiers. Multiple techniques have been designed to perform case selection. This paper empirically investigates how class imbalance in the available set of training cases can impact the performance of the resulting classifier as well as properties of the selected set. In this study, the experiments are performed using a dataset for the problem of detecting breast masses in screening mammograms. The classification problem was binary and we used a k-nearest neighbor classifier. The classifier’s performance was evaluated using the Receiver Operating Characteristic (ROC) area under the curve (AUC) measure. The experimental results indicate that although class imbalance reduces the performance of the derived classifier and the effectiveness of selection at improving overall classifier performance, case selection can still be beneficial, regardless of the level of class imbalance. PMID:21820273
Two Reconfigurable Flight-Control Design Methods: Robust Servomechanism and Control Allocation
NASA Technical Reports Server (NTRS)
Burken, John J.; Lu, Ping; Wu, Zheng-Lu; Bahm, Cathy
2001-01-01
Two methods for control system reconfiguration have been investigated. The first method is a robust servomechanism control approach (optimal tracking problem) that is a generalization of the classical proportional-plus-integral control to multiple input-multiple output systems. The second method is a control-allocation approach based on a quadratic programming formulation. A globally convergent fixed-point iteration algorithm has been developed to make onboard implementation of this method feasible. These methods have been applied to reconfigurable entry flight control design for the X-33 vehicle. Examples presented demonstrate simultaneous tracking of angle-of-attack and roll angle commands during failures of the fight body flap actuator. Although simulations demonstrate success of the first method in most cases, the control-allocation method appears to provide uniformly better performance in all cases.
Reconfigurable Flight Control Designs With Application to the X-33 Vehicle
NASA Technical Reports Server (NTRS)
Burken, John J.; Lu, Ping; Wu, Zhenglu
1999-01-01
Two methods for control system reconfiguration have been investigated. The first method is a robust servomechanism control approach (optimal tracking problem) that is a generalization of the classical proportional-plus-integral control to multiple input-multiple output systems. The second method is a control-allocation approach based on a quadratic programming formulation. A globally convergent fixed-point iteration algorithm has been developed to make onboard implementation of this method feasible. These methods have been applied to reconfigurable entry flight control design for the X-33 vehicle. Examples presented demonstrate simultaneous tracking of angle-of-attack and roll angle commands during failures of the right body flap actuator. Although simulations demonstrate success of the first method in most cases, the control-allocation method appears to provide uniformly better performance in all cases.
Stochastic production phase design for an open pit mining complex with multiple processing streams
NASA Astrophysics Data System (ADS)
Asad, Mohammad Waqar Ali; Dimitrakopoulos, Roussos; van Eldert, Jeroen
2014-08-01
In a mining complex, the mine is a source of supply of valuable material (ore) to a number of processes that convert the raw ore to a saleable product or a metal concentrate for production of the refined metal. In this context, expected variation in metal content throughout the extent of the orebody defines the inherent uncertainty in the supply of ore, which impacts the subsequent ore and metal production targets. Traditional optimization methods for designing production phases and ultimate pit limit of an open pit mine not only ignore the uncertainty in metal content, but, in addition, commonly assume that the mine delivers ore to a single processing facility. A stochastic network flow approach is proposed that jointly integrates uncertainty in supply of ore and multiple ore destinations into the development of production phase design and ultimate pit limit. An application at a copper mine demonstrates the intricacies of the new approach. The case study shows a 14% higher discounted cash flow when compared to the traditional approach.
Kamadjeu, Raoul; Gathenji, Caroline
2017-01-01
In April 2013, a case of wild polio virus (WPV) was detected in the Somalia capital Mogadishu. This inaugurated what is now referred to as the 2013-2014 Horn of Africa Polio outbreak with cases reported in Somalia, Kenya and Ethiopia. By the notification of the last polio case in August 2014, 223 cases of WPV had been reported in Somalia, Kenya and Ethiopia of which 199 in Somalia alone. The outbreak response required timely exchange of information between the outbreak response coordination unit (in Nairobi) and local staff located in multiple locations inside the country. The need to track and timely respond to information requests, to satisfy the information/data needs of polio partners and to track key outbreak response performance indicators dictated the need to urgently set up an online dashboard. The Somalia Polio Room dashboard provided a graphical display of the polio outbreak data to track progress and inform decision making. The system was designed using free and open sources components and seamlessly integrated existing polio surveillance data for real time monitoring of key outbreak response performance indicators. In this article, we describe the design and operation of an electronic dashboard for disease surveillance in an outbreak situation and used the lessons learned to propose key design considerations and functional requirements for online electronic dashboards for disease outbreak response. PMID:29296157
Kamadjeu, Raoul; Gathenji, Caroline
2017-01-01
In April 2013, a case of wild polio virus (WPV) was detected in the Somalia capital Mogadishu. This inaugurated what is now referred to as the 2013-2014 Horn of Africa Polio outbreak with cases reported in Somalia, Kenya and Ethiopia. By the notification of the last polio case in August 2014, 223 cases of WPV had been reported in Somalia, Kenya and Ethiopia of which 199 in Somalia alone. The outbreak response required timely exchange of information between the outbreak response coordination unit (in Nairobi) and local staff located in multiple locations inside the country. The need to track and timely respond to information requests, to satisfy the information/data needs of polio partners and to track key outbreak response performance indicators dictated the need to urgently set up an online dashboard. The Somalia Polio Room dashboard provided a graphical display of the polio outbreak data to track progress and inform decision making. The system was designed using free and open sources components and seamlessly integrated existing polio surveillance data for real time monitoring of key outbreak response performance indicators. In this article, we describe the design and operation of an electronic dashboard for disease surveillance in an outbreak situation and used the lessons learned to propose key design considerations and functional requirements for online electronic dashboards for disease outbreak response.
Visual Analysis of MOOC Forums with iForum.
Fu, Siwei; Zhao, Jian; Cui, Weiwei; Qu, Huamin
2017-01-01
Discussion forums of Massive Open Online Courses (MOOC) provide great opportunities for students to interact with instructional staff as well as other students. Exploration of MOOC forum data can offer valuable insights for these staff to enhance the course and prepare the next release. However, it is challenging due to the large, complicated, and heterogeneous nature of relevant datasets, which contain multiple dynamically interacting objects such as users, posts, and threads, each one including multiple attributes. In this paper, we present a design study for developing an interactive visual analytics system, called iForum, that allows for effectively discovering and understanding temporal patterns in MOOC forums. The design study was conducted with three domain experts in an iterative manner over one year, including a MOOC instructor and two official teaching assistants. iForum offers a set of novel visualization designs for presenting the three interleaving aspects of MOOC forums (i.e., posts, users, and threads) at three different scales. To demonstrate the effectiveness and usefulness of iForum, we describe a case study involving field experts, in which they use iForum to investigate real MOOC forum data for a course on JAVA programming.
Thermo-elasto-plastic simulations of femtosecond laser-induced multiple-cavity in fused silica
NASA Astrophysics Data System (ADS)
Beuton, R.; Chimier, B.; Breil, J.; Hébert, D.; Mishchik, K.; Lopez, J.; Maire, P. H.; Duchateau, G.
2018-04-01
The formation and the interaction of multiple cavities, induced by tightly focused femtosecond laser pulses, are studied using a developed numerical tool, including the thermo-elasto-plastic material response. Simulations are performed in fused silica in cases of one, two, and four spots of laser energy deposition. The relaxation of the heated matter, launching shock waves in the surrounding cold material, leads to cavity formation and emergence of areas where cracks may be induced. Results show that the laser-induced structure shape depends on the energy deposition configuration and demonstrate the potential of the used numerical tool to obtain the desired designed structure or technological process.
ERIC Educational Resources Information Center
Turner, Jill; Rafferty, Lisa A.; Sullivan, Ray; Blake, Amy
2017-01-01
In this action research case study, the researchers used a multiple baseline across two student pairs design to investigate the effects of the error self-correction method on the spelling accuracy behaviors for four fifth-grade students who were identified as being at risk for learning disabilities. The dependent variable was the participants'…
ERIC Educational Resources Information Center
Raulston, Tracy Jane
2017-01-01
In this study, a concurrent randomized multiple baseline across three parent-child dyads single-case design was employed to evaluate the effects of a brief three-week parent training program, titled Practiced Routines. The Practiced Routines parent training program included positive behavior supports (PBS) and mindfulness strategies within the…
Brug, Annet Ten; Van der Putten, Annette A J; Vlaskamp, Carla
2013-12-01
Knowledge about the preferences and abilities of children with profound intellectual and multiple disabilities (PIMDs) is crucial for providing appropriate activities. Multi-sensory storytelling (MSST) can be an ideal activity for gathering such knowledge about children with PIMDs. The aim of this study was to analyse whether using MSST did lead to changes in teachers' knowledge about preferences and abilities and whether this knowledge was then applied in practice. Three dyads of children with PIMDs and their teachers read an MSST book 20 times during a 10-week period. A questionnaire designed to identify the teachers' current knowledge was filled in before the 1st and again after the 10th and 20th reading sessions. Also, the teachers were asked for their opinion about their newly gathered knowledge. In all three cases, changes in the teachers' knowledge were observed. However, teachers are insufficiently aware of their new knowledge and do not apply it in practice.
People’s Preferences of Urban Design Qualities for Walking on a Commercial Street
NASA Astrophysics Data System (ADS)
Ernawati, J.; Surjono; Sudarmo, B. S.
2018-03-01
This research aims to explore people’s preferences of urban design qualities for walking on a commercial street, with Kawi Street located in a commercial neighborhood in the town of Malang Indonesia as the case study. Based on a literature review, this study used eight urban design qualities, i.e., enclosure, legibility, human scale, transparency, complexity, coherence, linkage, and imageability. This study applied a survey research method using a self-administered paper-pencil questionnaire applying two measurement techniques: Likert scale was used to explore people’s evaluations of urban design qualities of the street, while multiple-rating scales were used to measure people’s preference for walking on the street. One hundred and ten people randomly selected as respondents. Regression analysis was employed to explore the influence of urban design qualities on people preference for walking. Results indicated four urban design qualities that affect people’s choice for walking on a commercial street, i.e., transparency, coherence, linkage, and imageability. Implications of the findings will be discussed in the paper.
Worst-Case Energy Efficiency Maximization in a 5G Massive MIMO-NOMA System.
Chinnadurai, Sunil; Selvaprabhu, Poongundran; Jeong, Yongchae; Jiang, Xueqin; Lee, Moon Ho
2017-09-18
In this paper, we examine the robust beamforming design to tackle the energy efficiency (EE) maximization problem in a 5G massive multiple-input multiple-output (MIMO)-non-orthogonal multiple access (NOMA) downlink system with imperfect channel state information (CSI) at the base station. A novel joint user pairing and dynamic power allocation (JUPDPA) algorithm is proposed to minimize the inter user interference and also to enhance the fairness between the users. This work assumes imperfect CSI by adding uncertainties to channel matrices with worst-case model, i.e., ellipsoidal uncertainty model (EUM). A fractional non-convex optimization problem is formulated to maximize the EE subject to the transmit power constraints and the minimum rate requirement for the cell edge user. The designed problem is difficult to solve due to its nonlinear fractional objective function. We firstly employ the properties of fractional programming to transform the non-convex problem into its equivalent parametric form. Then, an efficient iterative algorithm is proposed established on the constrained concave-convex procedure (CCCP) that solves and achieves convergence to a stationary point of the above problem. Finally, Dinkelbach's algorithm is employed to determine the maximum energy efficiency. Comprehensive numerical results illustrate that the proposed scheme attains higher worst-case energy efficiency as compared with the existing NOMA schemes and the conventional orthogonal multiple access (OMA) scheme.
Worst-Case Energy Efficiency Maximization in a 5G Massive MIMO-NOMA System
Jeong, Yongchae; Jiang, Xueqin; Lee, Moon Ho
2017-01-01
In this paper, we examine the robust beamforming design to tackle the energy efficiency (EE) maximization problem in a 5G massive multiple-input multiple-output (MIMO)-non-orthogonal multiple access (NOMA) downlink system with imperfect channel state information (CSI) at the base station. A novel joint user pairing and dynamic power allocation (JUPDPA) algorithm is proposed to minimize the inter user interference and also to enhance the fairness between the users. This work assumes imperfect CSI by adding uncertainties to channel matrices with worst-case model, i.e., ellipsoidal uncertainty model (EUM). A fractional non-convex optimization problem is formulated to maximize the EE subject to the transmit power constraints and the minimum rate requirement for the cell edge user. The designed problem is difficult to solve due to its nonlinear fractional objective function. We firstly employ the properties of fractional programming to transform the non-convex problem into its equivalent parametric form. Then, an efficient iterative algorithm is proposed established on the constrained concave-convex procedure (CCCP) that solves and achieves convergence to a stationary point of the above problem. Finally, Dinkelbach’s algorithm is employed to determine the maximum energy efficiency. Comprehensive numerical results illustrate that the proposed scheme attains higher worst-case energy efficiency as compared with the existing NOMA schemes and the conventional orthogonal multiple access (OMA) scheme. PMID:28927019
Cross-continuum Care Continuity: Achieving Seamless Care and Managing Comorbidities.
Boston-Fleischhauer, Carol; Rose, Robert; Hartwig, Laurie
As healthcare systems continue to design care models responsive to payment changes and the assumption of clinical and financial risk, the need exists for a comprehensive approach to address cross-continuum care transitions. This article will highlight key learnings from the Nurse Executive Center's research on achieving care continuity. The business case for developing a cross-continuum care transition strategy will be discussed, as well as systemic enablers for the achievement of seamless care. A case study example of 1 system's solution for supporting the multiple comorbid patient population as part of its cross-continuum care transition strategy will be examined.
One-shot estimate of MRMC variance: AUC.
Gallas, Brandon D
2006-03-01
One popular study design for estimating the area under the receiver operating characteristic curve (AUC) is the one in which a set of readers reads a set of cases: a fully crossed design in which every reader reads every case. The variability of the subsequent reader-averaged AUC has two sources: the multiple readers and the multiple cases (MRMC). In this article, we present a nonparametric estimate for the variance of the reader-averaged AUC that is unbiased and does not use resampling tools. The one-shot estimate is based on the MRMC variance derived by the mechanistic approach of Barrett et al. (2005), as well as the nonparametric variance of a single-reader AUC derived in the literature on U statistics. We investigate the bias and variance properties of the one-shot estimate through a set of Monte Carlo simulations with simulated model observers and images. The different simulation configurations vary numbers of readers and cases, amounts of image noise and internal noise, as well as how the readers are constructed. We compare the one-shot estimate to a method that uses the jackknife resampling technique with an analysis of variance model at its foundation (Dorfman et al. 1992). The name one-shot highlights that resampling is not used. The one-shot and jackknife estimators behave similarly, with the one-shot being marginally more efficient when the number of cases is small. We have derived a one-shot estimate of the MRMC variance of AUC that is based on a probabilistic foundation with limited assumptions, is unbiased, and compares favorably to an established estimate.
Yakubova, Gulnoza; Hughes, Elizabeth M; Hornberger, Erin
2015-09-01
The purpose of this study was to determine the effectiveness of a point-of-view video modeling intervention to teach mathematics problem-solving when working on word problems involving subtracting mixed fractions with uncommon denominators. Using a multiple-probe across students design of single-case methodology, three high school students with ASD completed the study. All three students demonstrated greater accuracy in solving fraction word problems and maintained accuracy levels at a 1-week follow-up.
Park, Sung Woo; Oh, Tae Suk; Eom, Jin Sup; Sun, Yoon Chi; Suh, Hyun Suk; Hong, Joon Pio
2015-05-01
The reconstruction of the posterior trunk remains to be a challenge as defects can be extensive, with deep dead space, and fixation devices exposed. Our goal was to achieve a tension-free closure for complex defects on the posterior trunk. From August 2006 to May 2013, 18 cases were reconstructed with multiple flaps combining perforator(s) and local skin flaps. The reconstructions were performed using freestyle approach. Starting with propeller flap(s) in single or multilobed design and sequentially in conjunction with adjacent random pattern flaps such as fitting puzzle. All defects achieved tensionless primary closure. The final appearance resembled a jigsaw puzzle-like appearance. The average size of defect was 139.6 cm(2) (range, 36-345 cm(2)). A total of 26 perforator flaps were used in addition to 19 random pattern flaps for 18 cases. In all cases, a single perforator was used for each propeller flap. The defect and the donor site all achieved tension-free closure. The reconstruction was 100% successful without flap loss. One case of late infection was noted at 12 months after surgery. Using multiple lobe designed propeller flaps in conjunction with random pattern flaps in a freestyle approach, resembling putting a jigsaw puzzle together, we can achieve a tension-free closure by distributing the tension to multiple flaps, supplying sufficient volume to obliterate dead space, and have reliable vascularity as the flaps do not need to be oversized. This can be a viable approach to reconstruct extensive defects on the posterior trunk. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Culture, risk factors and suicide in rural China: a psychological autopsy case control study.
Zhang, J; Conwell, Y; Zhou, L; Jiang, C
2004-12-01
Previous research on sociocultural factors for Chinese suicide have been basically limited to single case studies or qualitative research with ethnographic methodology. The current study examines the major risk factors and some cultural uniqueness related to Chinese rural suicide using a quantitative design. This is a case control study with 66 completed suicides and 66 living controls obtained from psychological autopsy interviews in rural China. Both bivariate analyses and the multiple regression model have found that the Chinese rural suicide patterns are basically similar to those in most other cultures in the world: strong predictors of rural Chinese suicide are the psychopathological, psychological, and physical health variables, followed by social support and negative and stressful life events. Other significant correlates include lower education, poverty, religion, and family disputes. Culture has an important impact on suicide patterns in a society.
Culture, risk factors and suicide in rural China: a psychological autopsy case control study
Zhang, J.; Conwell, Y.; Zhou, L.; Jiang, C.
2009-01-01
Objective Previous research on sociocultural factors for Chinese suicide have been basically limited to single case studies or qualitative research with ethnographic methodology. The current study examines the major risk factors and some cultural uniqueness related to Chinese rural suicide using a quantitative design. Method This is a case control study with 66 completed suicides and 66 living controls obtained from psychological autopsy interviews in rural China. Results Both bivariate analyses and the multiple regression model have found that the Chinese rural suicide patterns are basically similar to those in most other cultures in the world: strong predictors of rural Chinese suicide are the psychopathological, psychological, and physical health variables, followed by social support and negative and stressful life events. Other significant correlates include lower education, poverty, religion, and family disputes. Conclusion Culture has an important impact on suicide patterns in a society. PMID:15521827
Distributed finite-time containment control for double-integrator multiagent systems.
Wang, Xiangyu; Li, Shihua; Shi, Peng
2014-09-01
In this paper, the distributed finite-time containment control problem for double-integrator multiagent systems with multiple leaders and external disturbances is discussed. In the presence of multiple dynamic leaders, by utilizing the homogeneous control technique, a distributed finite-time observer is developed for the followers to estimate the weighted average of the leaders' velocities at first. Then, based on the estimates and the generalized adding a power integrator approach, distributed finite-time containment control algorithms are designed to guarantee that the states of the followers converge to the dynamic convex hull spanned by those of the leaders in finite time. Moreover, as a special case of multiple dynamic leaders with zero velocities, the proposed containment control algorithms also work for the case of multiple stationary leaders without using the distributed observer. Simulations demonstrate the effectiveness of the proposed control algorithms.
Optimum Design of High-Speed Prop-Rotors
NASA Technical Reports Server (NTRS)
Chattopadhyay, Aditi; McCarthy, Thomas Robert
1993-01-01
An integrated multidisciplinary optimization procedure is developed for application to rotary wing aircraft design. The necessary disciplines such as dynamics, aerodynamics, aeroelasticity, and structures are coupled within a closed-loop optimization process. The procedure developed is applied to address two different problems. The first problem considers the optimization of a helicopter rotor blade and the second problem addresses the optimum design of a high-speed tilting proprotor. In the helicopter blade problem, the objective is to reduce the critical vibratory shear forces and moments at the blade root, without degrading rotor aerodynamic performance and aeroelastic stability. In the case of the high-speed proprotor, the goal is to maximize the propulsive efficiency in high-speed cruise without deteriorating the aeroelastic stability in cruise and the aerodynamic performance in hover. The problems studied involve multiple design objectives; therefore, the optimization problems are formulated using multiobjective design procedures. A comprehensive helicopter analysis code is used for the rotary wing aerodynamic, dynamic and aeroelastic stability analyses and an algorithm developed specifically for these purposes is used for the structural analysis. A nonlinear programming technique coupled with an approximate analysis procedure is used to perform the optimization. The optimum blade designs obtained in each case are compared to corresponding reference designs.
An omnibus test for family-based association studies with multiple SNPs and multiple phenotypes.
Lasky-Su, Jessica; Murphy, Amy; McQueen, Matthew B; Weiss, Scott; Lange, Christoph
2010-06-01
We propose an omnibus family-based association test (MFBAT) that can be applied to multiple markers and multiple phenotypes and that has only one degree of freedom. The proposed test statistic extends current FBAT methodology to incorporate multiple markers as well as multiple phenotypes. Using simulation studies, power estimates for the proposed methodology are compared with the standard methodologies. On the basis of these simulations, we find that MFBAT substantially outperforms other methods, including haplotypic approaches and doing multiple tests with single single-nucleotide polymorphisms (SNPs) and single phenotypes. The practical relevance of the approach is illustrated by an application to asthma in which SNP/phenotype combinations are identified and reach overall significance that would not have been identified using other approaches. This methodology is directly applicable to cases in which there are multiple SNPs, such as candidate gene studies, cases in which there are multiple phenotypes, such as expression data, and cases in which there are multiple phenotypes and genotypes, such as genome-wide association studies that incorporate expression profiles as phenotypes. This program is available in the PBAT analysis package.
Architecture for multi-technology real-time location systems.
Rodas, Javier; Barral, Valentín; Escudero, Carlos J
2013-02-07
The rising popularity of location-based services has prompted considerable research in the field of indoor location systems. Since there is no single technology to support these systems, it is necessary to consider the fusion of the information coming from heterogeneous sensors. This paper presents a software architecture designed for a hybrid location system where we can merge information from multiple sensor technologies. The architecture was designed to be used by different kinds of actors independently and with mutual transparency: hardware administrators, algorithm developers and user applications. The paper presents the architecture design, work-flow, case study examples and some results to show how different technologies can be exploited to obtain a good estimation of a target position.
Mechanically and electrically robust metal-mask design for organic CMOS circuits
NASA Astrophysics Data System (ADS)
Shintani, Michihiro; Qin, Zhaoxing; Kuribara, Kazunori; Ogasahara, Yasuhiro; Hiromoto, Masayuki; Sato, Takashi
2018-04-01
The design of metal masks for fabricating organic CMOS circuits requires the consideration of not only the electrical property of the circuits, but also the mechanical strength of the masks. In this paper, we propose a new design flow for metal masks that realizes coanalysis of the mechanical and electrical properties and enables design exploration considering the trade-off between the two properties. As a case study, we apply a “stitching technique” to the mask design of a ring oscillator and explore the best design. With this technique, mask patterns are divided into separate parts using multiple mask layers to improve the mechanical strength at the cost of high resistance of the vias. By a numerical experiment, the design trade-off of the stitching technique is quantitatively analyzed, and it is demonstrated that the proposed flow is useful for the exploration of the designs of metal masks.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harris, W; Hollebeek, R; Teo, B
2014-06-15
Purpose: Quality Assurance (QA) measurements of proton therapy fields must accurately measure steep longitudinal dose gradients as well as characterize the dose distribution laterally. Currently, available devices for two-dimensional field measurements perturb the dose distribution such that routine QA measurements performed at multiple depths require multiple field deliveries and are time consuming. Methods: A design procedure for a two-dimensional detector array is introduced whereby the proton energy loss and scatter are adjusted so that the downstream dose distribution is maintained to be equivalent to that which would occur in uniform water. Starting with the design for an existing, functional two-dimensionalmore » segmented ion chamber prototype, a compensating material is introduced downstream of the detector to simultaneously equate the energy loss and lateral scatter in the detector assembly to the values in water. An analytic formalism and procedure is demonstrated to calculate the properties of the compensating material in the general case of multiple layers of arbitrary material. The resulting design is validated with Monte Carlo simulations. Results: With respect to the specific prototype design considered, the results indicate that a graphite compensating layer of the proper dimensions can yield proton beam range perturbation less than 0.1mm and beam sigma perturbation less than 2% across the energy range of therapeutic proton beams. Conclusion: We have shown that, for a 2D gas-filled detector array, a graphite-compensating layer can balance the energy loss and multiple Coulomb scattering relative to uniform water. We have demonstrated an analytic formalism and procedure to determine a compensating material in the general case of multiple layers of arbitrary material. This work was supported by the US Army Medical Research and Materiel Command under Contract Agreement No. DAMD17-W81XWH-04-2-0022. Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the US Army.« less
NASA Astrophysics Data System (ADS)
Dounas-Frazer, Dimitri R.; Stanley, Jacob T.; Lewandowski, H. J.
2017-12-01
We investigate students' sense of ownership of multiweek final projects in an upper-division optics lab course. Using a multiple case study approach, we describe three student projects in detail. Within-case analyses focused on identifying key issues in each project, and constructing chronological descriptions of those events. Cross-case analysis focused on identifying emergent themes with respect to five dimensions of project ownership: student agency, instructor mentorship, peer collaboration, interest and value, and affective responses. Our within- and cross-case analyses yielded three major findings. First, coupling division of labor with collective brainstorming can help balance student agency, instructor mentorship, and peer collaboration. Second, students' interest in the project and perceptions of its value can increase over time; initial student interest in the project topic is not a necessary condition for student ownership of the project. Third, student ownership is characterized by a wide range of emotions that fluctuate as students alternate between extended periods of struggle and moments of success while working on their projects. These findings not only extend the literature on student ownership into a new educational domain—namely, upper-division physics labs—they also have concrete implications for the design of experimental physics projects in courses for which student ownership is a desired learning outcome. We describe the course and projects in sufficient detail that others can adapt our results to their particular contexts.
A Design Study to Develop Young Children's Understanding of Multiplication and Division
ERIC Educational Resources Information Center
Bicknell, Brenda; Young-Loveridge, Jenny; Nguyen, Nhung
2016-01-01
This design study investigated the use of multiplication and division problems to help 5-year-old children develop an early understanding of multiplication and division. One teacher and her class of 15 5-year-old children were involved in a collaborative partnership with the researchers. The design study was conducted over two 4-week periods in…
Willson, Rob; Veale, David; Freeston, Mark
2016-03-01
Individuals with body dysmorphic disorder (BDD) often experience negative distorted images of their appearance, and research suggests these may be linked to memories of adverse events such as bullying or teasing. This study evaluates imagery rescripting (ImR) as an intervention for BDD. In this article, we present a multiple-baseline single-case experimental design testing imagery rescripting as a brief, stand-alone intervention, with six individuals with BDD that related to aversive memories. The impact of the intervention was assessed by self-reported daily measures of symptom severity (preoccupation with appearance, appearance-related checking behaviors, appearance-related distress, and strength of belief that their main problem is their appearance) and standardized clinician ratings of BDD severity (Yale-Brown Obsessive Compulsive Scale modified for BDD). Four out of six of the participants responded positively to the intervention, with clinically meaningful improvement in symptomatology. Overall response was rapid; improvements began within the first week post-ImR intervention. From a small sample it is cautiously concluded that imagery rescripting may show promise as a module in cognitive-behavioral therapy for BDD, and is worthy of further investigation. Copyright © 2015. Published by Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Zuiker, Steven; Reid Whitaker, J.
2014-04-01
This paper describes the 5E+I/A inquiry model and reports a case study of one curricular enactment by a US fifth-grade classroom. A literature review establishes the model's conceptual adequacy with respect to longstanding research related to both the 5E inquiry model and multiple, incremental innovations of it. As a collective line of research, the review highlights a common emphasis on formative assessment, at times coupled either with differentiated instruction strategies or with activities that target the generalization of learning. The 5E+I/A model contributes a multi-level assessment strategy that balances formative and summative functions of multiple forms of assessment in order to support classroom participation while still attending to individual achievement. The case report documents the enactment of a weeklong 5E+I/A curricular design as a preliminary account of the model's empirical adequacy. A descriptive and analytical narrative illustrates variable ways that multi-level assessment makes student thinking visible and pedagogical decision-making more powerful. In light of both, it also documents productive adaptations to a flexible curricular design and considers future research to advance this collective line of inquiry.
Ghorbani, Neda; Rassafiani, Mehdi; Izadi-Najafabadi, Sara; Yazdani, Farzaneh; Akbarfahimi, Nazila; Havaei, Naser; Gharebaghy, Soraya
2017-12-01
Cerebral palsy (CP) is the most common cause of physical disabilities during childhood. Therapeutic interventions mainly focus on impairment reduction to address motor-based difficulties. In contrast, Cognitive Orientation to daily Occupational Performance (CO-OP) is a cognitive approach, providing intervention at the level of activity and participation. This study aims to determine whether the CO-OP approach improves motor skills and achievement in motor-based occupational performance goals in children with CP. In this mixed design research (i.e., a multiple baseline single case experimental design and a one-group pretest-posttest design), five children with CP participated in 12 CO-OP intervention sessions. Repeated measures of motor skills for the multiple baseline single case experimental design were taken using the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP); pre- and post-measures of parent/child perception of performance and satisfaction were identified using the Canadian Occupational Performance Measure (COPM); level of achievement was identified using Goal Attainment Scaling (GAS). According to the BOTMP results, all children were able to engage in the CO-OP intervention to improve motor performance. Significant differences after treatment were found in both performance and performance satisfaction ratings using the COPM as rated by parents and children. The GAS results showed progress in achievement levels for all children; all goals were achieved or exceeded. CO-OP intervention can be helpful in improving motor skills and achieving self-identified, motor-based goals in children with CP. Copyright © 2017. Published by Elsevier Ltd.
Tremblay, Dominique; Prady, Catherine; Bilodeau, Karine; Touati, Nassera; Chouinard, Maud-Christine; Fortin, Martin; Gaboury, Isabelle; Rodrigue, Jean; L'Italien, Marie-France
2017-12-16
Cancer is now viewed as a chronic disease, presenting challenges to follow-up and survivorship care. Models to shift from haphazard, suboptimal and fragmented episodes of care to an integrated cancer care continuum must be developed, tested and implemented. Numerous studies demonstrate improved care when follow-up is assured by both oncology and primary care providers rather than either group alone. However, there is little data on the roles assumed by specialized oncology teams and primary care providers and the extent to which they work together. This study aims to develop, pilot test and measure outcomes of an innovative risk-based coordinated cancer care model for patients transitioning from specialized oncology teams to primary care providers. This multiple case study using a sequential mixed-methods design rests on a theory-driven realist evaluation approach to understand how transitions might be improved. The cases are two health regions in Quebec, Canada, defined by their geographic territory. Each case includes a Cancer Centre and three Family Medicine Groups selected based on differences in their determining characteristics. Qualitative data will be collected from document review (scientific journal, grey literature, local documentation), semi-directed interviews with key informants, and observation of care coordination practices. Qualitative data will be supplemented with a survey to measure the outcome of the coordinated model among providers (scope of practice, collaboration, relational coordination, leadership) and patients diagnosed with breast, colorectal or prostate cancer (access to care, patient-centredness, communication, self-care, survivorship profile, quality of life). Results from descriptive and regression analyses will be triangulated with thematic analysis of qualitative data. Qualitative, quantitative, and mixed methods data will be interpreted within and across cases in order to identify context-mechanism associations that explain outcomes. The study will provide empirical data on a risk-based coordinated model of cancer care to guide actions at different levels in the health system. This in-depth multiple case study using a realist approach considers both the need for context-specific intervention research and the imperative to address research gaps regarding coordinated models of cancer care.
Aniba, Mohamed Radhouene; Siguenza, Sophie; Friedrich, Anne; Plewniak, Frédéric; Poch, Olivier; Marchler-Bauer, Aron; Thompson, Julie Dawn
2009-01-01
The traditional approach to bioinformatics analyses relies on independent task-specific services and applications, using different input and output formats, often idiosyncratic, and frequently not designed to inter-operate. In general, such analyses were performed by experts who manually verified the results obtained at each step in the process. Today, the amount of bioinformatics information continuously being produced means that handling the various applications used to study this information presents a major data management and analysis challenge to researchers. It is now impossible to manually analyse all this information and new approaches are needed that are capable of processing the large-scale heterogeneous data in order to extract the pertinent information. We review the recent use of integrated expert systems aimed at providing more efficient knowledge extraction for bioinformatics research. A general methodology for building knowledge-based expert systems is described, focusing on the unstructured information management architecture, UIMA, which provides facilities for both data and process management. A case study involving a multiple alignment expert system prototype called AlexSys is also presented.
Aniba, Mohamed Radhouene; Siguenza, Sophie; Friedrich, Anne; Plewniak, Frédéric; Poch, Olivier; Marchler-Bauer, Aron
2009-01-01
The traditional approach to bioinformatics analyses relies on independent task-specific services and applications, using different input and output formats, often idiosyncratic, and frequently not designed to inter-operate. In general, such analyses were performed by experts who manually verified the results obtained at each step in the process. Today, the amount of bioinformatics information continuously being produced means that handling the various applications used to study this information presents a major data management and analysis challenge to researchers. It is now impossible to manually analyse all this information and new approaches are needed that are capable of processing the large-scale heterogeneous data in order to extract the pertinent information. We review the recent use of integrated expert systems aimed at providing more efficient knowledge extraction for bioinformatics research. A general methodology for building knowledge-based expert systems is described, focusing on the unstructured information management architecture, UIMA, which provides facilities for both data and process management. A case study involving a multiple alignment expert system prototype called AlexSys is also presented. PMID:18971242
Blom, M T; van Hoeijen, D A; Bardai, A; Berdowski, J; Souverein, P C; De Bruin, M L; Koster, R W; de Boer, A; Tan, H L
2014-01-01
Out-of-hospital cardiac arrest (OHCA) is a major public health problem. Recognising the complexity of the underlying causes of OHCA in the community, we aimed to establish the clinical, pharmacological, environmental and genetic factors and their interactions that may cause OHCA. We set up a large-scale prospective community-based registry (AmsteRdam Resuscitation Studies, ARREST) in which we prospectively include all resuscitation attempts from OHCA in a large study region in the Netherlands in collaboration with Emergency Medical Services. Of all OHCA victims since June 2005, we prospectively collect medical history (through hospital and general practitioner), and current and previous medication use (through community pharmacy). In addition, we include DNA samples from OHCA victims with documented ventricular tachycardia/fibrillation during the resuscitation attempt since July 2007. Various study designs are employed to analyse the data of the ARREST registry, including case-control, cohort, case only and case-cross over designs. We describe the rationale, outline and potential results of the ARREST registry. The design allows for a stable and reliable collection of multiple determinants of OHCA, while assuring that the patient, lay-caregiver or medical professional is not hindered in any way. Such comprehensive data collection is required to unravel the complex basis of OHCA. Results will be published in peer-reviewed journals and presented at relevant scientific symposia.
Hoonakker, Peter L T; Carayon, Pascale; Cartmill, Randi S
2017-04-01
Secure messaging is a relatively new addition to health information technology (IT). Several studies have examined the impact of secure messaging on (clinical) outcomes but very few studies have examined the impact on workflow in primary care clinics. In this study we examined the impact of secure messaging on workflow of clinicians, staff and patients. We used a multiple case study design with multiple data collections methods (observation, interviews and survey). Results show that secure messaging has the potential to improve communication and information flow and the organization of work in primary care clinics, partly due to the possibility of asynchronous communication. However, secure messaging can also have a negative effect on communication and increase workload, especially if patients send messages that are not appropriate for the secure messaging medium (for example, messages that are too long, complex, ambiguous, or inappropriate). Results show that clinicians are ambivalent about secure messaging. Secure messaging can add to their workload, especially if there is high message volume, and currently they are not compensated for these activities. Staff is -especially compared to clinicians- relatively positive about secure messaging and patients are overall very satisfied with secure messaging. Finally, clinicians, staff and patients think that secure messaging can have a positive effect on quality of care and patient safety. Secure messaging is a tool that has the potential to improve communication and information flow. However, the potential of secure messaging to improve workflow is dependent on the way it is implemented and used. Copyright © 2017 Elsevier B.V. All rights reserved.
A Decision-Support System for Sustainable Water Distribution System Planning.
Freund, Alina; Aydin, Nazli Yonca; Zeckzer, Dirk; Hagen, Hans
2017-01-01
An interactive decision-support system (DSS) can help experts prepare water resource management plans for decision makers and stakeholders. The design of the proposed prototype incorporates visualization techniques such as circle views, grid layout, small multiple maps, and node simplification to improve the data readability of water distribution systems. A case study with three urban water management and sanitary engineering experts revealed that the proposed DSS is satisfactory, efficient, and effective.
ERIC Educational Resources Information Center
Tompkins, David K.
2017-01-01
For the past few decades, the trend of first generation low-economic status community college students, considerably comprised of immigrants, has continued to grow at a significant rate (Connell, 2008; Ray, 2013; Kim & Diaz, 2013c; Kim, 2014). Community colleges are encountering challenges that were previously viewed as minimal or secondary to…
Effort to Accelerate MBSE Adoption and Usage at JSC
NASA Technical Reports Server (NTRS)
Wang, Lui; Izygon, Michel; Okron, Shira; Garner, Larry; Wagner, Howard
2016-01-01
This paper describes the authors' experience in adopting Model Based System Engineering (MBSE) at the NASA/Johnson Space Center (JSC). Since 2009, NASA/JSC has been applying MBSE using the Systems Modeling Language (SysML) to a number of advanced projects. Models integrate views of the system from multiple perspectives, capturing the system design information for multiple stakeholders. This method has allowed engineers to better control changes, improve traceability from requirements to design and manage the numerous interactions between components. As the project progresses, the models become the official source of information and used by multiple stakeholders. Three major types of challenges that hamper the adoption of the MBSE technology are described. These challenges are addressed by a multipronged approach that includes educating the main stakeholders, implementing an organizational infrastructure that supports the adoption effort, defining a set of modeling guidelines to help engineers in their modeling effort, providing a toolset that support the generation of valuable products, and providing a library of reusable models. JSC project case studies are presented to illustrate how the proposed approach has been successfully applied.
Shea, Christopher Michael; Belden, Charles M
2016-01-12
Although champions are commonly employed in health information technology (HIT) implementations, the state of empirical literature on HIT champions' is unclear. The purpose of our review was to synthesize quantitative and qualitative studies to identify the extent of research on the characteristics, behaviors, and impacts of HIT champions. Ultimately, our goal was to identify gaps in the literature and inform implementation science. Our review employed a broad search strategy using multiple databases-Embase, Pubmed, Cinahl, PsychInfo, Web of Science, and the Cochrane library. We identified 1728 candidate articles, of which 42 were retained for full-text review. Of the 42 studies included, fourteen studies employed a multiple-case study design (33 %), 12 additional articles employed a single-case study design (29 %), five used quantitative methods (12 %), two used mixed-methods (5 %), and one used a Delphi methodology (2 %). Our review revealed multiple categories and characteristics of champions as well as influence tactics they used to promote an HIT project. Furthermore, studies have assessed three general types of HIT champion impacts: (1) impacts on the implementation process of a specific HIT; (2) impacts on usage behavior or overall success of a specific HIT; and (3) impacts on general organizational-level innovativeness. However the extent to which HIT projects fail even with a champion and why such failures occur is not clear. Also unclear is whether all organizations require a champion for successful HIT project implementation. In other words, we currently do not know enough about the conditions under which (1) a health IT champion is needed, (2) multiple champions are needed, and (3) an appointed champion-as opposed to an emergent champion-can be successful. Although champions appear to have contributed to successful implementation of HIT projects, simply measuring the presence or absence of a champion is not sufficient for assessing impacts. Future research should aim for answers to questions about who champions should be, when they should be engaged, what they should do, how management can support their efforts, and what their impact is given the organizational context.
Zhou, Hanzhi; Elliott, Michael R; Raghunathan, Trivellore E
2016-06-01
Multistage sampling is often employed in survey samples for cost and convenience. However, accounting for clustering features when generating datasets for multiple imputation is a nontrivial task, particularly when, as is often the case, cluster sampling is accompanied by unequal probabilities of selection, necessitating case weights. Thus, multiple imputation often ignores complex sample designs and assumes simple random sampling when generating imputations, even though failing to account for complex sample design features is known to yield biased estimates and confidence intervals that have incorrect nominal coverage. In this article, we extend a recently developed, weighted, finite-population Bayesian bootstrap procedure to generate synthetic populations conditional on complex sample design data that can be treated as simple random samples at the imputation stage, obviating the need to directly model design features for imputation. We develop two forms of this method: one where the probabilities of selection are known at the first and second stages of the design, and the other, more common in public use files, where only the final weight based on the product of the two probabilities is known. We show that this method has advantages in terms of bias, mean square error, and coverage properties over methods where sample designs are ignored, with little loss in efficiency, even when compared with correct fully parametric models. An application is made using the National Automotive Sampling System Crashworthiness Data System, a multistage, unequal probability sample of U.S. passenger vehicle crashes, which suffers from a substantial amount of missing data in "Delta-V," a key crash severity measure.
Zhou, Hanzhi; Elliott, Michael R.; Raghunathan, Trivellore E.
2017-01-01
Multistage sampling is often employed in survey samples for cost and convenience. However, accounting for clustering features when generating datasets for multiple imputation is a nontrivial task, particularly when, as is often the case, cluster sampling is accompanied by unequal probabilities of selection, necessitating case weights. Thus, multiple imputation often ignores complex sample designs and assumes simple random sampling when generating imputations, even though failing to account for complex sample design features is known to yield biased estimates and confidence intervals that have incorrect nominal coverage. In this article, we extend a recently developed, weighted, finite-population Bayesian bootstrap procedure to generate synthetic populations conditional on complex sample design data that can be treated as simple random samples at the imputation stage, obviating the need to directly model design features for imputation. We develop two forms of this method: one where the probabilities of selection are known at the first and second stages of the design, and the other, more common in public use files, where only the final weight based on the product of the two probabilities is known. We show that this method has advantages in terms of bias, mean square error, and coverage properties over methods where sample designs are ignored, with little loss in efficiency, even when compared with correct fully parametric models. An application is made using the National Automotive Sampling System Crashworthiness Data System, a multistage, unequal probability sample of U.S. passenger vehicle crashes, which suffers from a substantial amount of missing data in “Delta-V,” a key crash severity measure. PMID:29226161
The emergence of designed multiple ligands for neurodegenerative disorders.
Geldenhuys, Werner J; Youdim, Moussa B H; Carroll, Richard T; Van der Schyf, Cornelis J
2011-09-01
The incidence of neurodegenerative diseases has seen a constant increase in the global population, and is likely to be the result of extended life expectancy brought about by better health care. Despite this increase in the incidence of neurodegenerative diseases, there has been a dearth in the introduction of new disease-modifying therapies that are approved to prevent or delay the onset of these diseases, or reverse the degenerative processes in brain. Mounting evidence in the peer-reviewed literature shows that the etiopathology of these diseases is extremely complex and heterogeneous, resulting in significant comorbidity and therefore unlikely to be mitigated by any drug acting on a single pathway or target. A recent trend in drug design and discovery is the rational design or serendipitous discovery of novel drug entities with the ability to address multiple drug targets that form part of the complex pathophysiology of a particular disease state. In this review we discuss the rationale for developing such multifunctional drugs (also called designed multiple ligands or DMLs), and why these drug candidates seem to offer better outcomes in many cases compared to single-targeted drugs in pre-clinical studies for neurodegenerative diseases such as Alzheimer's and Parkinson's disease. Examples are drawn from the literature of drug candidates that have already reached the market, some unsuccessful attempts, and others that are still in the drug development pipeline. Copyright © 2011. Published by Elsevier Ltd.
Landi, Maria Teresa; Consonni, Dario; Rotunno, Melissa; Bergen, Andrew W; Goldstein, Alisa M; Lubin, Jay H; Goldin, Lynn; Alavanja, Michael; Morgan, Glen; Subar, Amy F; Linnoila, Ilona; Previdi, Fabrizio; Corno, Massimo; Rubagotti, Maurizia; Marinelli, Barbara; Albetti, Benedetta; Colombi, Antonio; Tucker, Margaret; Wacholder, Sholom; Pesatori, Angela C; Caporaso, Neil E; Bertazzi, Pier Alberto
2008-06-06
Lung cancer is the leading cause of cancer mortality worldwide. Tobacco smoking is its primary cause, and yet the precise molecular alterations induced by smoking in lung tissue that lead to lung cancer and impact survival have remained obscure. A new framework of research is needed to address the challenges offered by this complex disease. We designed a large population-based case-control study that combines a traditional molecular epidemiology design with a more integrative approach to investigate the dynamic process that begins with smoking initiation, proceeds through dependency/smoking persistence, continues with lung cancer development and ends with progression to disseminated disease or response to therapy and survival. The study allows the integration of data from multiple sources in the same subjects (risk factors, germline variation, genomic alterations in tumors, and clinical endpoints) to tackle the disease etiology from different angles. Before beginning the study, we conducted a phone survey and pilot investigations to identify the best approach to ensure an acceptable participation in the study from cases and controls. Between 2002 and 2005, we enrolled 2101 incident primary lung cancer cases and 2120 population controls, with 86.6% and 72.4% participation rate, respectively, from a catchment area including 216 municipalities in the Lombardy region of Italy. Lung cancer cases were enrolled in 13 hospitals and population controls were randomly sampled from the area to match the cases by age, gender and residence. Detailed epidemiological information and biospecimens were collected from each participant, and clinical data and tissue specimens from the cases. Collection of follow-up data on treatment and survival is ongoing. EAGLE is a new population-based case-control study that explores the full spectrum of lung cancer etiology, from smoking addiction to lung cancer outcome, through examination of epidemiological, molecular, and clinical data. We have provided a detailed description of the study design, field activities, management, and opportunities for research following this integrative approach, which allows a sharper and more comprehensive vision of the complex nature of this disease. The study is poised to accelerate the emergence of new preventive and therapeutic strategies with potentially enormous impact on public health.
A stochastic approach for automatic generation of urban drainage systems.
Möderl, M; Butler, D; Rauch, W
2009-01-01
Typically, performance evaluation of new developed methodologies is based on one or more case studies. The investigation of multiple real world case studies is tedious and time consuming. Moreover extrapolating conclusions from individual investigations to a general basis is arguable and sometimes even wrong. In this article a stochastic approach is presented to evaluate new developed methodologies on a broader basis. For the approach the Matlab-tool "Case Study Generator" is developed which generates a variety of different virtual urban drainage systems automatically using boundary conditions e.g. length of urban drainage system, slope of catchment surface, etc. as input. The layout of the sewer system is based on an adapted Galton-Watson branching process. The sub catchments are allocated considering a digital terrain model. Sewer system components are designed according to standard values. In total, 10,000 different virtual case studies of urban drainage system are generated and simulated. Consequently, simulation results are evaluated using a performance indicator for surface flooding. Comparison between results of the virtual and two real world case studies indicates the promise of the method. The novelty of the approach is that it is possible to get more general conclusions in contrast to traditional evaluations with few case studies.
A new piezoelectric energy harvesting design concept: multimodal energy harvesting skin.
Lee, Soobum; Youn, Byeng D
2011-03-01
This paper presents an advanced design concept for a piezoelectric energy harvesting (EH), referred to as multimodal EH skin. This EH design facilitates the use of multimodal vibration and enhances power harvesting efficiency. The multimodal EH skin is an extension of our previous work, EH skin, which was an innovative design paradigm for a piezoelectric energy harvester: a vibrating skin structure and an additional thin piezoelectric layer in one device. A computational (finite element) model of the multilayered assembly - the vibrating skin structure and piezoelectric layer - is constructed and the optimal topology and/or shape of the piezoelectric layer is found for maximum power generation from multiple vibration modes. A design rationale for the multimodal EH skin was proposed: designing a piezoelectric material distribution and external resistors. In the material design step, the piezoelectric material is segmented by inflection lines from multiple vibration modes of interests to minimize voltage cancellation. The inflection lines are detected using the voltage phase. In the external resistor design step, the resistor values are found for each segment to maximize power output. The presented design concept, which can be applied to any engineering system with multimodal harmonic-vibrating skins, was applied to two case studies: an aircraft skin and a power transformer panel. The excellent performance of multimodal EH skin was demonstrated, showing larger power generation than EH skin without segmentation or unimodal EH skin.
Wang, Jian; Spitz, Margaret R; Amos, Christopher I; Wu, Xifeng; Wetter, David W; Cinciripini, Paul M; Shete, Sanjay
2012-01-01
A mediation model explores the direct and indirect effects between an independent variable and a dependent variable by including other variables (or mediators). Mediation analysis has recently been used to dissect the direct and indirect effects of genetic variants on complex diseases using case-control studies. However, bias could arise in the estimations of the genetic variant-mediator association because the presence or absence of the mediator in the study samples is not sampled following the principles of case-control study design. In this case, the mediation analysis using data from case-control studies might lead to biased estimates of coefficients and indirect effects. In this article, we investigated a multiple-mediation model involving a three-path mediating effect through two mediators using case-control study data. We propose an approach to correct bias in coefficients and provide accurate estimates of the specific indirect effects. Our approach can also be used when the original case-control study is frequency matched on one of the mediators. We employed bootstrapping to assess the significance of indirect effects. We conducted simulation studies to investigate the performance of the proposed approach, and showed that it provides more accurate estimates of the indirect effects as well as the percent mediated than standard regressions. We then applied this approach to study the mediating effects of both smoking and chronic obstructive pulmonary disease (COPD) on the association between the CHRNA5-A3 gene locus and lung cancer risk using data from a lung cancer case-control study. The results showed that the genetic variant influences lung cancer risk indirectly through all three different pathways. The percent of genetic association mediated was 18.3% through smoking alone, 30.2% through COPD alone, and 20.6% through the path including both smoking and COPD, and the total genetic variant-lung cancer association explained by the two mediators was 69.1%.
Open Rotor Tone Shielding Methods for System Noise Assessments Using Multiple Databases
NASA Technical Reports Server (NTRS)
Bahr, Christopher J.; Thomas, Russell H.; Lopes, Leonard V.; Burley, Casey L.; Van Zante, Dale E.
2014-01-01
Advanced aircraft designs such as the hybrid wing body, in conjunction with open rotor engines, may allow for significant improvements in the environmental impact of aviation. System noise assessments allow for the prediction of the aircraft noise of such designs while they are still in the conceptual phase. Due to significant requirements of computational methods, these predictions still rely on experimental data to account for the interaction of the open rotor tones with the hybrid wing body airframe. Recently, multiple aircraft system noise assessments have been conducted for hybrid wing body designs with open rotor engines. These assessments utilized measured benchmark data from a Propulsion Airframe Aeroacoustic interaction effects test. The measured data demonstrated airframe shielding of open rotor tonal and broadband noise with legacy F7/A7 open rotor blades. Two methods are proposed for improving the use of these data on general open rotor designs in a system noise assessment. The first, direct difference, is a simple octave band subtraction which does not account for tone distribution within the rotor acoustic signal. The second, tone matching, is a higher-fidelity process incorporating additional physical aspects of the problem, where isolated rotor tones are matched by their directivity to determine tone-by-tone shielding. A case study is conducted with the two methods to assess how well each reproduces the measured data and identify the merits of each. Both methods perform similarly for system level results and successfully approach the experimental data for the case study. The tone matching method provides additional tools for assessing the quality of the match to the data set. Additionally, a potential path to improve the tone matching method is provided.
Brehmer, Matthew; Ingram, Stephen; Stray, Jonathan; Munzner, Tamara
2014-12-01
For an investigative journalist, a large collection of documents obtained from a Freedom of Information Act request or a leak is both a blessing and a curse: such material may contain multiple newsworthy stories, but it can be difficult and time consuming to find relevant documents. Standard text search is useful, but even if the search target is known it may not be possible to formulate an effective query. In addition, summarization is an important non-search task. We present Overview, an application for the systematic analysis of large document collections based on document clustering, visualization, and tagging. This work contributes to the small set of design studies which evaluate a visualization system "in the wild", and we report on six case studies where Overview was voluntarily used by self-initiated journalists to produce published stories. We find that the frequently-used language of "exploring" a document collection is both too vague and too narrow to capture how journalists actually used our application. Our iterative process, including multiple rounds of deployment and observations of real world usage, led to a much more specific characterization of tasks. We analyze and justify the visual encoding and interaction techniques used in Overview's design with respect to our final task abstractions, and propose generalizable lessons for visualization design methodology.
Multi-point Adjoint-Based Design of Tilt-Rotors in a Noninertial Reference Frame
NASA Technical Reports Server (NTRS)
Jones, William T.; Nielsen, Eric J.; Lee-Rausch, Elizabeth M.; Acree, Cecil W.
2014-01-01
Optimization of tilt-rotor systems requires the consideration of performance at multiple design points. In the current study, an adjoint-based optimization of a tilt-rotor blade is considered. The optimization seeks to simultaneously maximize the rotorcraft figure of merit in hover and the propulsive efficiency in airplane-mode for a tilt-rotor system. The design is subject to minimum thrust constraints imposed at each design point. The rotor flowfields at each design point are cast as steady-state problems in a noninertial reference frame. Geometric design variables used in the study to control blade shape include: thickness, camber, twist, and taper represented by as many as 123 separate design variables. Performance weighting of each operational mode is considered in the formulation of the composite objective function, and a build up of increasing geometric degrees of freedom is used to isolate the impact of selected design variables. In all cases considered, the resulting designs successfully increase both the hover figure of merit and the airplane-mode propulsive efficiency for a rotor designed with classical techniques.
NASA Astrophysics Data System (ADS)
Wang, Hongfeng; Fu, Yaping; Huang, Min; Wang, Junwei
2016-03-01
The operation process design is one of the key issues in the manufacturing and service sectors. As a typical operation process, the scheduling with consideration of the deteriorating effect has been widely studied; however, the current literature only studied single function requirement and rarely considered the multiple function requirements which are critical for a real-world scheduling process. In this article, two function requirements are involved in the design of a scheduling process with consideration of the deteriorating effect and then formulated into two objectives of a mathematical programming model. A novel multiobjective evolutionary algorithm is proposed to solve this model with combination of three strategies, i.e. a multiple population scheme, a rule-based local search method and an elitist preserve strategy. To validate the proposed model and algorithm, a series of randomly-generated instances are tested and the experimental results indicate that the model is effective and the proposed algorithm can achieve the satisfactory performance which outperforms the other state-of-the-art multiobjective evolutionary algorithms, such as nondominated sorting genetic algorithm II and multiobjective evolutionary algorithm based on decomposition, on all the test instances.
Thompson, Trevor DB
2004-01-01
Background Two main pathways exist for the development of knowledge in clinical homeopathy. These comprise clinical trials conducted primarily by university-based researchers and cases reports and homeopathic "provings" compiled by engaged homeopathic practitioners. In this paper the relative merits of these methods are examined and a middle way proposed. This consists of the "Formal Case Study" (FCS) in which qualitative methods are used to increase the rigour and sophistication with which homeopathic cases are studied. Before going into design issues this paper places the FCS in an historical and academic context and describes the relative merits of the method. Discussion Like any research, the FCS should have a clear focus. This focus can be both "internal", grounded in the discourse of homeopathy and also encompass issues of wider appeal. A selection of possible "internal" and "external" research questions is introduced. Data generation should be from multiple sources to ensure adequate triangulation. This could include the recording and transcription of actual consultations. Analysis is built around existing theory, involves cross-case comparison and the search for deviant cases. The trustworthiness of conclusions is ensured by the application of concepts from qualitative research including triangulation, groundedness, respondent validation and reflexivity. Though homeopathic case studies have been reported in mainstream literature, none has used formal qualitative methods – though some such studies are in progress. Summary This paper introduces the reader to a new strategy for homeopathic research. This strategy, termed the "formal case study", allows for a naturalistic enquiry into the players, processes and outcomes of homeopathic practice. Using ideas from qualitative research, it allows a rigorous approach to types of research question that cannot typically be addressed through clinical trials and numeric outcome studies. The FCS provides an opportunity for the practitioner-researcher to contribute to the evidence-base in homeopathy in a systematic fashion. The FCS can also be used to inform the design of clinical trials through holistic study of the "active ingredients" of the therapeutic process and its clinical outcomes. PMID:15018637
NASA Astrophysics Data System (ADS)
Goff, P.; Hulse, A.; Harder, H. R.; Pierce, L. A.; Rizzo, D.; Hanley, J.; Orantes, L.; Stevens, L.; Justi, S.; Monroy, C.
2015-12-01
A computational simulation has been designed as an investigative case study by high school students to introduce system dynamics modeling into high school curriculum. This case study approach leads users through the forensics necessary to diagnose an unknown disease in a Central American village. This disease, Chagas, is endemic to 21 Latin American countries. The CDC estimates that of the 110 million people living in areas with the disease, 8 million are infected, with as many as 300,000 US cases. Chagas is caused by the protozoan parasite, Trypanosoma cruzi, and is spread via blood feeding insect (vectors), that feed on vertebrates and live in crevasses in the walls and roofs of adobe homes. One-third of the infected people will develop chronic Chagas who are asymptomatic for years before their heart or GI tract become enlarged resulting in death. The case study has three parts. Students play the role of WHO field investigators and work collaboratively to: 1) use genetics to identify the host(s) and vector of the disease 2) use a STELLA™ SIR (Susceptible, Infected, Recovered) system dynamics model to study Chagas at the village scale and 3) develop management strategies. The simulations identify mitigation strategies known as Ecohealth Interventions (e.g., home improvements using local materials) to help stakeholders test and compare multiple optima. High school students collaborated with researchers from the University of Vermont, Loyola University and Universidad de San Carlos, Guatemala, working in labs, interviewing researchers, and incorporating mulitple field data as part of a NSF-funded multiyear grant. The model displays stable equilibria of hosts, vectors, and disease-states. Sensitivity analyses show measures of household condition and presence of vertebrates were significant leverage points, supporting other findings by the University research team. The village-scale model explores multiple solutions to disease mitigation for the purpose of producing students who can think long-term, better understand feedbacks, and anticipate unexpected consequences associated with non-linear systems. This case study enables high school teachers to incorporate ongoing research, systems modeling, and engineering design, three core goals Next Generation Science Standards and STEM initiatives.
The Case for Architecture by Committee
ERIC Educational Resources Information Center
Building Design and Construction, 1972
1972-01-01
Multiple-architect designs and a preservative of chain-store identities accomplish visual variety for a one-of-a-kind campus at Evergreen State College in Olympia, Washington, and an enclosed shopping mall in Los Cerritos, California. (Author)
Packing Boxes into Multiple Containers Using Genetic Algorithm
NASA Astrophysics Data System (ADS)
Menghani, Deepak; Guha, Anirban
2016-07-01
Container loading problems have been studied extensively in the literature and various analytical, heuristic and metaheuristic methods have been proposed. This paper presents two different variants of a genetic algorithm framework for the three-dimensional container loading problem for optimally loading boxes into multiple containers with constraints. The algorithms are designed so that it is easy to incorporate various constraints found in real life problems. The algorithms are tested on data of standard test cases from literature and are found to compare well with the benchmark algorithms in terms of utilization of containers. This, along with the ability to easily incorporate a wide range of practical constraints, makes them attractive for implementation in real life scenarios.
Haakma, Ineke; Janssen, Marleen; Minnaert, Alexander
2016-01-01
Because little is known about teacher-student relationships that involve students with acquired deafblindness, the authors performed a multiple case study with a multiple-method design to investigate the relationship between need-supportive teaching behaviors and student engagement. Using self-determination theory (Deci & Ryan, 2000), they analyzed video observations of interactions. It was found that teachers' provision of structure, autonomy support, and involvement often cooccurs with higher levels of student engagement. Moreover, varying degrees of need support over time seem to result in varying levels of student engagement. Examples are provided of need-supportive teaching behaviors that can be used to foster the motivation of students with acquired deafblindness.
NASA Astrophysics Data System (ADS)
Mehta, Neville; Kompalli, Suryaprakash; Chaudhary, Vipin
Teleradiology is the electronic transmission of radiological patient images, such as x-rays, CT, or MR across multiple locations. The goal could be interpretation, consultation, or medical records keeping. Information technology solutions have enabled electronic records and their associated benefits are evident in health care today. However, salient aspects of collaborative interfaces, and computer assisted diagnostic (CAD) tools are yet to be integrated into workflow designs. The Computer Assisted Diagnostics and Interventions (CADI) group at the University at Buffalo has developed an architecture that facilitates web-enabled use of CAD tools, along with the novel concept of synchronized collaboration. The architecture can support multiple teleradiology applications and case studies are presented here.
Cold in-place recycling characterization framework for single or multiple component binder systems
NASA Astrophysics Data System (ADS)
Cox, Benjamin C.
Cold in-place recycling (CIR) is a pavement rehabilitation technique which has gained momentum in recent years. This momentum is due partly to its economic and sustainability characteristics, which has led to CIR market expansion. When pavement network deterioration is considered alongside increasing material costs, it is not beyond reason to expect demands on CIR to continue to increase. Historically, single component binder (SCB) systems, those with one stabilization binder (or two if the secondary binder dosage is 1% or less), have dominated the CIR market and could be considered the general state of practice. Common stabilization binders are either bituminous or cementitious. Two example SCB systems would be: 1) 3% portland cement, or 2) 3% asphalt emulsion with 1% hydrated lime. While traditional SCB systems have demonstrated positive economic and sustainability impacts, this dissertation focuses on multiple component binder (MCB) systems (bituminous and cementitious combined) which exhibit the potential to provide better overall economics and performance. Use of MCBs has the potential to alleviate SCB issues to some extent (e.g. cracking with cementitious SCBs, rutting with bituminous SCBs). Furthermore, to fairly represent both binders in an MCB system a universal design method which can accommodate multiple binder types is needed. The main objectives of this dissertation are to develop a universal CIR design framework and, using this framework, characterize multiple SCB and MCB systems. Approximately 1500 CIR specimens were tested herein along with approximately 300 asphalt concrete specimens which serve as a reference data set for CIR characterization. A case study of a high-traffic Mississippi CIR project which included cement SCB and emulsion SCB sections is also presented to support laboratory efforts. Individual components needed to comprise a universal design framework, such as curing protocols, were developed. SCB and MCB characterization indicated that cement SCBs yielded low cracking resistance, high rutting resistance, and lower costs. Emulsion SCBs yielded the opposite. MCBs demonstrated the ability to balance rutting, cracking, and economics. Overall, the universal framework presented appears promising as it could offer agencies flexibility and, in some cases, improved overall performance beyond that of current SCB design methods.
The effects of particulate air pollution on daily deaths: a multi-city case crossover analysis
Schwartz, J
2004-01-01
Background: Numerous studies have reported that day-to-day changes in particulate air pollution are associated with day-to-day changes in deaths. Recently, several reports have indicated that the software used to control for season and weather in some of these studies had deficiencies. Aims: To investigate the use of the case-crossover design as an alternative. Methods: This approach compares the exposure of each case to their exposure on a nearby day, when they did not die. Hence it controls for seasonal patterns and for all slowly varying covariates (age, smoking, etc) by matching rather than complex modelling. A key feature is that temperature can also be controlled by matching. This approach was applied to a study of 14 US cities. Weather and day of the week were controlled for in the regression. Results: A 10 µg/m3 increase in PM10 was associated with a 0.36% increase in daily deaths from internal causes (95% CI 0.22% to 0.50%). Results were little changed if, instead of symmetrical sampling of control days the time stratified method was applied, when control days were matched on temperature, or when more lags of winter time temperatures were used. Similar results were found using a Poisson regression, but the case-crossover method has the advantage of simplicity in modelling, and of combining matched strata across multiple locations in a single stage analysis. Conclusions: Despite the considerable differences in analytical design, the previously reported associations of particles with mortality persisted in this study. The association appeared quite linear. Case-crossover designs represent an attractive method to control for season and weather by matching. PMID:15550600
Schulze, Matthias B.; Weikert, Cornelia; Pischon, Tobias; Bergmann, Manuela M.; Al-Hasani, Hadi; Schleicher, Erwin; Fritsche, Andreas; Häring, Hans-Ulrich; Boeing, Heiner; Joost, Hans-Georg
2009-01-01
OBJECTIVE We investigated whether metabolic biomarkers and single nucleotide polymorphisms (SNPs) improve diabetes prediction beyond age, anthropometry, and lifestyle risk factors. RESEARCH DESIGN AND METHODS A case-cohort study within a prospective study was designed. We randomly selected a subcohort (n = 2,500) from 26,444 participants, of whom 1,962 were diabetes free at baseline. Of the 801 incident type 2 diabetes cases identified in the cohort during 7 years of follow-up, 579 remained for analyses after exclusions. Prediction models were compared by receiver operatoring characteristic (ROC) curve and integrated discrimination improvement. RESULTS Case-control discrimination by the lifestyle characteristics (ROC-AUC: 0.8465) improved with plasma glucose (ROC-AUC: 0.8672, P < 0.001) and A1C (ROC-AUC: 0.8859, P < 0.001). ROC-AUC further improved with HDL cholesterol, triglycerides, γ-glutamyltransferase, and alanine aminotransferase (0.9000, P = 0.002). Twenty SNPs did not improve discrimination beyond these characteristics (P = 0.69). CONCLUSIONS Metabolic markers, but not genotyping for 20 diabetogenic SNPs, improve discrimination of incident type 2 diabetes beyond lifestyle risk factors. PMID:19720844
Treatment of Obsessive Compulsive Disorder in Young Children: An Intervention Model and Case Series
ERIC Educational Resources Information Center
Ginsburg, Golda S.; Burstein, Marcy; Becker, Kimberly D.; Drake, Kelly L.
2011-01-01
This article presents an intervention model for young children with obsessive-compulsive disorder (OCD). The intervention, designed to reduce compulsive behavior and improve parenting practices, was tested using a multiple baseline design with 7 children (M = 6 years old; 57% female) in which participants were randomly assigned to 1, 2, or 3 weeks…
Stout, N; Bell, C
1991-06-01
The complete and accurate identification of fatal occupational injuries among the US work force is an important first step in developing work injury prevention efforts. Numerous sources of information, such as death certificates, Workers' Compensation files, Occupational Safety and Health Administration (OSHA) files, medical examiner records, state health and labor department reports, and various combinations of these, have been used to identify cases of work-related fatal injuries. Recent studies have questioned the effectiveness of these sources for identifying such cases. At least 10 studies have used multiple sources to define the universe of fatal work injuries within a state and to determine the capture rates, or proportion of the universe identified, by each source. Results of these studies, which are not all available in published literature, are summarized here in a format that allows researchers to readily compare the ascertainment capabilities of the sources. The overall average capture rates of sources were as follows: death certificates, 81%; medical examiner records, 61%; Workers' Compensation reports, 57%; and OSHA reports 32%. Variations by state and value added through the use of multiple sources are presented and discussed. This meta-analysis of 10 state-based studies summarizes the effectiveness of various source documents for capturing cases of fatal occupational injuries to help researchers make informed decisions when designing occupational injury surveillance systems.
Ridde, Valéry; Yaogo, Maurice; Zongo, Sylvie; Somé, Paul-André; Turcotte-Tremblay, Anne-Marie
2018-01-01
To improve health services' quantity and quality, African countries are increasingly engaging in performance-based financing (PBF) interventions. Studies to understand their implementation in francophone West Africa are rare. This study analysed PBF implementation in Burkina Faso 12 months post-launch in late 2014. The design was a multiple and contrasted case study involving 18 cases (health centres). Empirical data were collected from observations, informal (n = 224) and formal (n = 459) interviews, and documents. Outside the circle of persons trained in PBF, few in the community had knowledge of it. In some health centres, the fact that staff were receiving bonuses was intentionally not announced to populations and community leaders. Most local actors thought PBF was just another project, but the majority appreciated it. There were significant delays in setting up agencies for performance monitoring, auditing, and contracting, as well as in the payment. The first audits led rapidly to coping strategies among health workers and occasionally to some staging beforehand. No community-based audits had yet been done. Distribution of bonuses varied from one centre to another. This study shows the importance of understanding the implementation of public health interventions in Africa and of uncovering coping strategies. © 2017 The Authors. The International Journal of Health Planning and Management Published by John Wiley & Sons Ltd.
Stout, N; Bell, C
1991-01-01
BACKGROUND: The complete and accurate identification of fatal occupational injuries among the US work force is an important first step in developing work injury prevention efforts. Numerous sources of information, such as death certificates, Workers' Compensation files, Occupational Safety and Health Administration (OSHA) files, medical examiner records, state health and labor department reports, and various combinations of these, have been used to identify cases of work-related fatal injuries. Recent studies have questioned the effectiveness of these sources for identifying such cases. METHODS: At least 10 studies have used multiple sources to define the universe of fatal work injuries within a state and to determine the capture rates, or proportion of the universe identified, by each source. Results of these studies, which are not all available in published literature, are summarized here in a format that allows researchers to readily compare the ascertainment capabilities of the sources. RESULTS: The overall average capture rates of sources were as follows: death certificates, 81%; medical examiner records, 61%; Workers' Compensation reports, 57%; and OSHA reports 32%. Variations by state and value added through the use of multiple sources are presented and discussed. CONCLUSIONS: This meta-analysis of 10 state-based studies summarizes the effectiveness of various source documents for capturing cases of fatal occupational injuries to help researchers make informed decisions when designing occupational injury surveillance systems. PMID:1827569
ERIC Educational Resources Information Center
Dounas-Frazer, Dimitri R.; Stanley, Jacob T.; Lewandowski, H. J.
2017-01-01
We investigate students' sense of ownership of multiweek final projects in an upper-division optics lab course. Using a multiple case study approach, we describe three student projects in detail. Within-case analyses focused on identifying key issues in each project, and constructing chronological descriptions of those events. Cross-case analysis…
Fractional Programming for Communication Systems—Part I: Power Control and Beamforming
NASA Astrophysics Data System (ADS)
Shen, Kaiming; Yu, Wei
2018-05-01
This two-part paper explores the use of FP in the design and optimization of communication systems. Part I of this paper focuses on FP theory and on solving continuous problems. The main theoretical contribution is a novel quadratic transform technique for tackling the multiple-ratio concave-convex FP problem--in contrast to conventional FP techniques that mostly can only deal with the single-ratio or the max-min-ratio case. Multiple-ratio FP problems are important for the optimization of communication networks, because system-level design often involves multiple signal-to-interference-plus-noise ratio terms. This paper considers the applications of FP to solving continuous problems in communication system design, particularly for power control, beamforming, and energy efficiency maximization. These application cases illustrate that the proposed quadratic transform can greatly facilitate the optimization involving ratios by recasting the original nonconvex problem as a sequence of convex problems. This FP-based problem reformulation gives rise to an efficient iterative optimization algorithm with provable convergence to a stationary point. The paper further demonstrates close connections between the proposed FP approach and other well-known algorithms in the literature, such as the fixed-point iteration and the weighted minimum mean-square-error beamforming. The optimization of discrete problems is discussed in Part II of this paper.
Rossi, Sabrina; Pitidis, Alessio
2018-01-01
Objective: Systematic bibliography analysis of about the last 17 years on multiple chemical sensitivity (MCS) was carried out in order to detect new diagnostic and epidemiological evidence. The MCS is a complex syndrome that manifests as a result of exposure to a low level of various common contaminants. The etiology, diagnosis, and treatment are still debated among researchers. Method: Querying PubMed, Web of Science, Scopus, Cochrane library, both using some specific MESH terms combined with MESH subheadings and through free search, even by Google. Results: The studies were analyzed by verifying 1) the typology of study design; 2) criteria for case definition; 3) presence of attendances in the emergency departments and hospital admissions, and 4) analysis of the risk factors. Outlook: With this review, we give some general considerations and hypothesis for possible future research. PMID:29111991
Shiu, Ann T Y; Lee, Diana T F; Chau, Janita P C
2012-08-01
This article is a report on a study to explore the development of expanding advanced nursing practice in nurse-led clinics in Hong Kong. Nurse-led clinics serviced by advanced practice nurses, a common international practice, have been adopted in Hong Kong since 1990s. Evaluations consistently show that this practice has good clinical outcomes and contributes to containing healthcare cost. However, similar to the international literature, it remains unclear as to what the elements of good advanced nursing practice are, and which directions Hong Kong should adopt for further development of such practice. A multiple-case study design was adopted with six nurse-led clinics representing three specialties as six case studies, and including two clinics each from continence, diabetes and wound care. Each case had four embedded units of analysis. They included non-participant observation of nursing activities (9 days), nurse interviews (N = 6), doctor interviews (N = 6) and client interviews (N = 12). The data were collected in 2009. Within- and cross-case analyses were conducted. The cross-case analysis demonstrated six elements of good advanced nursing practice in nurse-led clinics, and showed a great potential to expand the practice by reshaping four categories of current boundaries, including community-hospital, wellness-illness, public-private and professional-practice boundaries. From these findings, we suggest a model to advance the scope of advanced nursing practice in nurse-led clinics. The six elements may be applied as audit criteria for evaluation of advanced nursing practice in nurse-led clinics, and the proposed model provides directions for expanding such practice in Hong Kong and beyond. © 2011 Blackwell Publishing Ltd.
Coquet, Julia Becaria; Tumas, Natalia; Osella, Alberto Ruben; Tanzi, Matteo; Franco, Isabella; Diaz, Maria Del Pilar
2016-01-01
A number of studies have evidenced the effect of modifiable lifestyle factors such as diet, breastfeeding and nutritional status on breast cancer risk. However, none have addressed the missing data problem in nutritional epidemiologic research in South America. Missing data is a frequent problem in breast cancer studies and epidemiological settings in general. Estimates of effect obtained from these studies may be biased, if no appropriate method for handling missing data is applied. We performed Multiple Imputation for missing values on covariates in a breast cancer case-control study of Córdoba (Argentina) to optimize risk estimates. Data was obtained from a breast cancer case control study from 2008 to 2015 (318 cases, 526 controls). Complete case analysis and multiple imputation using chained equations were the methods applied to estimate the effects of a Traditional dietary pattern and other recognized factors associated with breast cancer. Physical activity and socioeconomic status were imputed. Logistic regression models were performed. When complete case analysis was performed only 31% of women were considered. Although a positive association of Traditional dietary pattern and breast cancer was observed from both approaches (complete case analysis OR=1.3, 95%CI=1.0-1.7; multiple imputation OR=1.4, 95%CI=1.2-1.7), effects of other covariates, like BMI and breastfeeding, were only identified when multiple imputation was considered. A Traditional dietary pattern, BMI and breastfeeding are associated with the occurrence of breast cancer in this Argentinean population when multiple imputation is appropriately performed. Multiple Imputation is suggested in Latin America’s epidemiologic studies to optimize effect estimates in the future. PMID:27892664
Steinwand, Daniel R.; Maddox, Brian; Beckmann, Tim; Hamer, George
2003-01-01
Beowulf clusters can provide a cost-effective way to compute numerical models and process large amounts of remote sensing image data. Usually a Beowulf cluster is designed to accomplish a specific set of processing goals, and processing is very efficient when the problem remains inside the constraints of the original design. There are cases, however, when one might wish to compute a problem that is beyond the capacity of the local Beowulf system. In these cases, spreading the problem to multiple clusters or to other machines on the network may provide a cost-effective solution.
Batistatou, Evridiki; McNamee, Roseanne
2012-12-10
It is known that measurement error leads to bias in assessing exposure effects, which can however, be corrected if independent replicates are available. For expensive replicates, two-stage (2S) studies that produce data 'missing by design', may be preferred over a single-stage (1S) study, because in the second stage, measurement of replicates is restricted to a sample of first-stage subjects. Motivated by an occupational study on the acute effect of carbon black exposure on respiratory morbidity, we compare the performance of several bias-correction methods for both designs in a simulation study: an instrumental variable method (EVROS IV) based on grouping strategies, which had been recommended especially when measurement error is large, the regression calibration and the simulation extrapolation methods. For the 2S design, either the problem of 'missing' data was ignored or the 'missing' data were imputed using multiple imputations. Both in 1S and 2S designs, in the case of small or moderate measurement error, regression calibration was shown to be the preferred approach in terms of root mean square error. For 2S designs, regression calibration as implemented by Stata software is not recommended in contrast to our implementation of this method; the 'problematic' implementation of regression calibration although substantially improved with use of multiple imputations. The EVROS IV method, under a good/fairly good grouping, outperforms the regression calibration approach in both design scenarios when exposure mismeasurement is severe. Both in 1S and 2S designs with moderate or large measurement error, simulation extrapolation severely failed to correct for bias. Copyright © 2012 John Wiley & Sons, Ltd.
Nickels, Lyndsey; Howard, David; Best, Wendy
2012-01-01
Cognitive neuropsychology has championed the use of single-case research design. Recently, however, case series designs that employ multiple single cases have been increasingly utilized to address theoretical issues using data from neuropsychological populations. In this paper, we examine these methodologies, focusing on a number of points in particular. First we discuss the use of dissociations and associations, often thought of as a defining feature of cognitive neuropsychology, and argue that they are better viewed as part of a spectrum of methods that aim to explain and predict behaviour. We also raise issues regarding case series design in particular, arguing that selection of an appropriate sample, including controlling degree of homogeneity, is critical and constrains the theoretical claims that can be made on the basis of the data. We discuss the possible interpretation of “outliers” in a case series, suggesting that while they may reflect “noise” caused by variability in performance due to factors that are not of relevance to the theoretical claims, they may also reflect the presence of patterns that are critical to test, refine, and potentially falsify our theories. The role of case series in treatment research is also raised, in light of the fact that, despite their status as gold standard, randomized controlled trials cannot provide answers to many crucial theoretical and clinical questions. Finally, we stress the importance of converging evidence: We propose that it is conclusions informed by multiple sources of evidence that are likely to best inform theory and stand the test of time. PMID:22746689
ERIC Educational Resources Information Center
Klenk, Jessicia A.; Pufpaff, Lisa A.
2011-01-01
Research on literacy instruction for students with multiple disabilities is limited. Empirical research on braille instruction for students with multiple disabilities that include congenital blindness is virtually nonexistent. This case study offers initial insight into possible methods of early braille literacy instruction for a student with…
2016-04-30
focus on novel onshore/offshore and small/large scale wind turbine designs for expanding their operational range and increasing their efficiency at...of maintenance options created by the implementation of PHM in wind turbines . When an RUL is predicted for a subsystem, there are multiple choices...The section titled Example— Wind Turbine With an Outcome-Based Contract presents a case study for a PHM enabled wind turbine with and without an
A systematic review of nonsurgical single-visit versus multiple-visit endodontic treatment
Wong, Amy WY; Zhang, Chengfei; Chu, Chun-hung
2014-01-01
Conventional endodontic treatment used to require multiple visits, but some clinicians have suggested that single-visit treatment is superior. Single-visit endodontic treatment and multiple-visit endodontic treatment both have their advantages and disadvantages. This paper is a literature review of the research on nonsurgical single-visit versus multiple-visit endodontic treatment. The PubMed database was searched using the keywords (endodontic treatment OR endodontic therapy OR root canal treatment OR root canal therapy) AND (single-visit OR one-visit OR 1-visit). Review papers, case reports, data studies, and irrelevant reports were excluded, and 47 papers on clinical trials were reviewed. The studies generally had small sample sizes, and the endodontic procedures varied among the studies. Meta-analysis on the selected studies was performed, and the results showed that the postoperative complications of the single-visit and multiple-visit endodontic treatment were similar. Furthermore, neither single-visit endodontic treatment nor multiple-visit treatment had superior results over the other in terms of healing or success rate. Results of limited studies on disinfection of the root canals using low-energy laser photodynamic therapy is inconclusive, and further studies are necessary to show whether laser should be used in endodontic treatment. This review also found that that neither single-visit endodontic treatment nor multiple-visit treatment could guarantee the absence of postoperative pain. Since the study design of many studies displayed significant limitation and the materials and equipment used in endodontic treatment have dramatically changed in recent years, prospective randomized clinical trials are needed to further verify the postoperative pain and success rates of single-visit versus multiple-visit endodontic treatment. PMID:24855389
Architecture for Multi-Technology Real-Time Location Systems
Rodas, Javier; Barral, Valentín; Escudero, Carlos J.
2013-01-01
The rising popularity of location-based services has prompted considerable research in the field of indoor location systems. Since there is no single technology to support these systems, it is necessary to consider the fusion of the information coming from heterogeneous sensors. This paper presents a software architecture designed for a hybrid location system where we can merge information from multiple sensor technologies. The architecture was designed to be used by different kinds of actors independently and with mutual transparency: hardware administrators, algorithm developers and user applications. The paper presents the architecture design, work-flow, case study examples and some results to show how different technologies can be exploited to obtain a good estimation of a target position. PMID:23435050
Simplified filtered Smith predictor for MIMO processes with multiple time delays.
Santos, Tito L M; Torrico, Bismark C; Normey-Rico, Julio E
2016-11-01
This paper proposes a simplified tuning strategy for the multivariable filtered Smith predictor. It is shown that offset-free control can be achieved with step references and disturbances regardless of the poles of the primary controller, i.e., integral action is not explicitly required. This strategy reduces the number of design parameters and simplifies tuning procedure because the implicit integrative poles are not considered for design purposes. The simplified approach can be used to design continuous-time or discrete-time controllers. Three case studies are used to illustrate the advantages of the proposed strategy if compared with the standard approach, which is based on the explicit integrative action. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.
An Object-Oriented Collection of Minimum Degree Algorithms: Design, Implementation, and Experiences
NASA Technical Reports Server (NTRS)
Kumfert, Gary; Pothen, Alex
1999-01-01
The multiple minimum degree (MMD) algorithm and its variants have enjoyed 20+ years of research and progress in generating fill-reducing orderings for sparse, symmetric positive definite matrices. Although conceptually simple, efficient implementations of these algorithms are deceptively complex and highly specialized. In this case study, we present an object-oriented library that implements several recent minimum degree-like algorithms. We discuss how object-oriented design forces us to decompose these algorithms in a different manner than earlier codes and demonstrate how this impacts the flexibility and efficiency of our C++ implementation. We compare the performance of our code against other implementations in C or Fortran.
Making Meaning with Multimedia in Secondary English Language Arts: A Multiple Case Study
ERIC Educational Resources Information Center
Mahoney, Kerrigan Rose
2016-01-01
The purpose of this multiple case study was to learn about how secondary English language arts (ELA) teachers help students to make meaning with multimedia. The study focused on how and why teachers plan and implement meaning-making learning experiences. The cases represent the experiences and perspectives of five ELA teachers who use digital and…
Finite element analysis of 6 large PMMA skull reconstructions: A multi-criteria evaluation approach
Ridwan-Pramana, Angela; Marcián, Petr; Borák, Libor; Narra, Nathaniel; Forouzanfar, Tymour; Wolff, Jan
2017-01-01
In this study 6 pre-operative designs for PMMA based reconstructions of cranial defects were evaluated for their mechanical robustness using finite element modeling. Clinical experience and engineering principles were employed to create multiple plan options, which were subsequently computationally analyzed for mechanically relevant parameters under 50N loads: stress, strain and deformation in various components of the assembly. The factors assessed were: defect size, location and shape. The major variable in the cranioplasty assembly design was the arrangement of the fixation plates. An additional study variable introduced was the location of the 50N load within the implant area. It was found that in smaller defects, it was simpler to design a symmetric distribution of plates and under limited variability in load location it was possible to design an optimal for expected loads. However, for very large defects with complex shapes, the variability in the load locations introduces complications to the intuitive design of the optimal assembly. The study shows that it can be beneficial to incorporate multi design computational analyses to decide upon the most optimal plan for a clinical case. PMID:28609471
Finite element analysis of 6 large PMMA skull reconstructions: A multi-criteria evaluation approach.
Ridwan-Pramana, Angela; Marcián, Petr; Borák, Libor; Narra, Nathaniel; Forouzanfar, Tymour; Wolff, Jan
2017-01-01
In this study 6 pre-operative designs for PMMA based reconstructions of cranial defects were evaluated for their mechanical robustness using finite element modeling. Clinical experience and engineering principles were employed to create multiple plan options, which were subsequently computationally analyzed for mechanically relevant parameters under 50N loads: stress, strain and deformation in various components of the assembly. The factors assessed were: defect size, location and shape. The major variable in the cranioplasty assembly design was the arrangement of the fixation plates. An additional study variable introduced was the location of the 50N load within the implant area. It was found that in smaller defects, it was simpler to design a symmetric distribution of plates and under limited variability in load location it was possible to design an optimal for expected loads. However, for very large defects with complex shapes, the variability in the load locations introduces complications to the intuitive design of the optimal assembly. The study shows that it can be beneficial to incorporate multi design computational analyses to decide upon the most optimal plan for a clinical case.
Dynamics of Implementation and Maintenance of Organizational Health Interventions.
Jalali, Mohammad S; Rahmandad, Hazhir; Bullock, Sally Lawrence; Ammerman, Alice
2017-08-15
In this study, we present case studies to explore the dynamics of implementation and maintenance of health interventions. We analyze how specific interventions are built and eroded, how the building and erosion mechanisms are interconnected, and why we can see significantly different erosion rates across otherwise similar organizations. We use multiple comparative obesity prevention case studies to provide empirical information on the mechanisms of interest, and use qualitative systems modeling to integrate our evolving understanding into an internally consistent and transparent theory of the phenomenon. Our preliminary results identify reinforcing feedback mechanisms, including design of organizational processes, motivation of stakeholders, and communication among stakeholders, which influence implementation and maintenance of intervention components. Over time, these feedback mechanisms may drive a wedge between otherwise similar organizations, leading to distinct configurations of implementation and maintenance processes.
21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.
Code of Federal Regulations, 2011 CFR
2011-04-01
... vivo bioavailability study. 320.27 Section 320.27 Food and Drugs FOOD AND DRUG ADMINISTRATION... Guidelines on the design of a multiple-dose in vivo bioavailability study. (a) Basic principles. (1) In... labeling of the test product. (3) A multiple-dose study may be required to determine the bioavailability of...
NASA Astrophysics Data System (ADS)
Liu, Yongfang; Zhao, Yu; Chen, Guanrong
2016-11-01
This paper studies the distributed consensus and containment problems for a group of harmonic oscillators with a directed communication topology. First, for consensus without a leader, a class of distributed consensus protocols is designed by using motion planning and Pontryagin's principle. The proposed protocol only requires relative information measurements at the sampling instants, without requiring information exchange over the sampled interval. By using stability theory and the properties of stochastic matrices, it is proved that the distributed consensus problem can be solved in the motion planning framework. Second, for the case with multiple leaders, a class of distributed containment protocols is developed for followers such that their positions and velocities can ultimately converge to the convex hull formed by those of the leaders. Compared with the existing consensus algorithms, a remarkable advantage of the proposed sampled-data-based protocols is that the sampling periods, communication topologies and control gains are all decoupled and can be separately designed, which relaxes many restrictions in controllers design. Finally, some numerical examples are given to illustrate the effectiveness of the analytical results.
NASA Technical Reports Server (NTRS)
1978-01-01
Design concepts of an array for the formation of multiple, simultaneous, independently pointed beams for satellite communication links were investigated through tradeoffs of various approaches which were conceived as possible solutions to the problem. After the preferred approach was selected, a more detailed design was configured and is presented as a candidate system that should be given further consideration for development leading to a preliminary design. This array uses an attenuator and a phase shifter with every element. The aperture excitation necessary to form the four beams is calculated and then placed across the array using these devices. Pattern analysis was performed for two beam and four beam cases with numerous patterns being presented. Parameter evaluation shown includes pointing accuracy and beam shape, sidelobe characteristics, gain control, and beam normalization. It was demonstrated that a 4 bit phase shifter and a 6 bit, 30 dB attenuator were sufficient to achieve adequate pattern performances. The phase amplitude steered multibeam array offers the flexibility of 1 to 4 beams with an increase in gain of 6 dB if only one beam is selected.
Carlos, Silvia; Lopez-Del Burgo, Cristina; Burgueño, Eduardo; Martinez-Gonzalez, Miguel Angel; Osorio, Alfonso; Ndarabu, Adolphe; Passabosc, Clément; de Irala, Jokin
2017-06-01
In the Democratic Republic of Congo no previous studies have assessed the factors associated with different patterns of condom use and with multiple sexual partners, and the association between condom use simultaneously taking into account multiple sexual partnerships, and HIV infection. We carried out a prospective case-control study. From December 2010 until June 2012, 1630 participants aged 15-49 getting HIV Voluntary Counseling and Testing in a hospital in Kinshasa were selected. Cases were new HIV diagnosis and controls were HIV-negative participants detected along the study period. We recruited 274 cases and 1340 controls that were interviewed about HIV-related knowledge, attitudes and behaviours. Among cases there was a high prevalence of multiple lifetime and concurrent sexual partnerships (89.8% and 20.4%, respectively) and most cases never used condoms with only 1.5% using them consistently. Condom use and multiple partnerships were associated with male, single and high-educated participants. An association was found between multiple lifetime partners and 'any condom use' (OR = 2.99; 95%CI: 2.14-4.19) but not with consistent use. Both having two or more multiple concurrent sexual partners or not using condoms were variables similarly and highly associated to HIV risk. The association found between having two or more concurrent sexual partners and HIV was slightly higher (OR = 3.58, 95%CI:2.31-5.56) than the association found between never condom use and HIV (OR = 3.38, 95%CI:1.15-9.93). We found a high prevalence of multiple lifetime sexual partners and an extremely high prevalence of inconsistent condom use, both strongly associated with HIV seropositivity. Local programmes would benefit from comprehensive interventions targeting all behavioural and sociocultural determinants.
Breaking down the gut microbiome composition in multiple sclerosis.
Budhram, Adrian; Parvathy, Seema; Kremenchutzky, Marcelo; Silverman, Michael
2017-04-01
The gut microbiome, which consists of a highly diverse ecologic community of micro-organisms, has increasingly been studied regarding its role in multiple sclerosis (MS) immunopathogenesis. This review critically examines the literature investigating the gut microbiome in MS. A comprehensive search was performed of PubMed databases and ECTRIMS meeting abstracts for literature relating to the gut microbiome in MS. Controlled studies examining the gut microbiome in patients with MS were included for review. Identified studies were predominantly case-control in their design and consistently found differences in the gut microbiome of MS patients compared to controls. We examine plausible mechanistic links between these differences and MS immunopathogenesis, and discuss the therapeutic implications of these findings. Review of the available literature reveals potential immunopathogenic links between the gut microbiome and MS, identifies avenues for therapeutic advancement, and emphasizes the need for further systematic study in this emerging field.
Two stage low noise advanced technology fan. 1: Aerodynamic, structural, and acoustic design
NASA Technical Reports Server (NTRS)
Messenger, H. E.; Ruschak, J. T.; Sofrin, T. G.
1974-01-01
A two-stage fan was designed to reduce noise 20 db below current requirements. The first-stage rotor has a design tip speed of 365.8 m/sec and a hub/tip ratio of 0.4. The fan was designed to deliver a pressure ratio of 1.9 with an adiabatic efficiency of 85.3 percent at a specific inlet corrected flow of 209.2kg/sec/sq m. Noise reduction devices include acoustically treated casing walls, a flowpath exit acoustic splitter, a translating centerbody sonic inlet device, widely spaced blade rows, and the proper ratio of blades and vanes. Multiple-circular-arc rotor airfoils, resettable stators, split outer casings, and capability to go to close blade-row spacing are also included.
Air pollution by particulate matter PM10 may trigger multiple sclerosis relapses.
Roux, Jonathan; Bard, Denis; Le Pabic, Estelle; Segala, Claire; Reis, Jacques; Ongagna, Jean-Claude; de Sèze, Jérôme; Leray, Emmanuelle
2017-07-01
Seasonal variation of relapses in multiple sclerosis (MS) suggests that season-dependent factors, such as ambient air pollution, may trigger them. However, only few studies have considered possible role of air pollutants as relapse's risk factor. We investigated the effect of particulate matter of aerodynamic diameter smaller than 10µm (PM 10 ) on MS relapses. In total, 536 relapsing MS patients from Strasbourg city (France) were included, accounting for 2052 relapses over 2000-2009 period. A case-crossover design was used with cases defined as the days of relapse and controls being selected in the same patient at plus and minus 35 days. Different lags from 0 to 30 days were considered. Conditional logistic regressions, adjusted on meteorological parameters, school and public holidays, were used and exposure was considered first as a quantitative variable and second, as a binary variable. The natural logarithm of the average PM 10 concentration lagged from 1 to 3 days before relapse onset was significantly associated with relapse risk (OR =1.40 [95% confidence interval 1.08-1.81]) in cold season. Consistent results were observed when considering PM 10 as a binary variable, even if not significant. With an appropriate study design and robust ascertainment of neurological events and exposure, the present study highlights the effect of PM 10 on the risk of relapse in MS patients, probably through oxidative stress mechanisms. Copyright © 2017 Elsevier Inc. All rights reserved.
Sequence Diversity Diagram for comparative analysis of multiple sequence alignments.
Sakai, Ryo; Aerts, Jan
2014-01-01
The sequence logo is a graphical representation of a set of aligned sequences, commonly used to depict conservation of amino acid or nucleotide sequences. Although it effectively communicates the amount of information present at every position, this visual representation falls short when the domain task is to compare between two or more sets of aligned sequences. We present a new visual presentation called a Sequence Diversity Diagram and validate our design choices with a case study. Our software was developed using the open-source program called Processing. It loads multiple sequence alignment FASTA files and a configuration file, which can be modified as needed to change the visualization. The redesigned figure improves on the visual comparison of two or more sets, and it additionally encodes information on sequential position conservation. In our case study of the adenylate kinase lid domain, the Sequence Diversity Diagram reveals unexpected patterns and new insights, for example the identification of subgroups within the protein subfamily. Our future work will integrate this visual encoding into interactive visualization tools to support higher level data exploration tasks.
Optimal design of compact and connected nature reserves for multiple species.
Wang, Yicheng; Önal, Hayri
2016-04-01
When designing a conservation reserve system for multiple species, spatial attributes of the reserves must be taken into account at species level. The existing optimal reserve design literature considers either one spatial attribute or when multiple attributes are considered the analysis is restricted only to one species. We built a linear integer programing model that incorporates compactness and connectivity of the landscape reserved for multiple species. The model identifies multiple reserves that each serve a subset of target species with a specified coverage probability threshold to ensure the species' long-term survival in the reserve, and each target species is covered (protected) with another probability threshold at the reserve system level. We modeled compactness by minimizing the total distance between selected sites and central sites, and we modeled connectivity of a selected site to its designated central site by selecting at least one of its adjacent sites that has a nearer distance to the central site. We considered structural distance and functional distances that incorporated site quality between sites. We tested the model using randomly generated data on 2 species, one ground species that required structural connectivity and the other an avian species that required functional connectivity. We applied the model to 10 bird species listed as endangered by the state of Illinois (U.S.A.). Spatial coherence and selection cost of the reserves differed substantially depending on the weights assigned to these 2 criteria. The model can be used to design a reserve system for multiple species, especially species whose habitats are far apart in which case multiple disjunct but compact and connected reserves are advantageous. The model can be modified to increase or decrease the distance between reserves to reduce or promote population connectivity. © 2015 Society for Conservation Biology.
Multiple Ejection Effects Analysis
1981-08-01
in future designs . Accession For * I N’IS CRA&I PTIV TAB\\ U:,zmnounced Ja St if ic ft IonL- 1) i tributIon/ Availability Codes Avail and/or )Ibt...between aircraft separation and drogue line stretch. In the case I of the crew module, design changes were eventually adopted to provide a stable...system, and the attitude excursions are very mild. The ejection seat system underwent an important design change because of high-speed aerodynamic
State Politics and Education: An Examination of Selected Multiple-State Case Studies.
ERIC Educational Resources Information Center
Burlingame, Martin; Geske, Terry G.
1979-01-01
Reviews the multiple-state case study literature, highlights some findings, discusses several methodological issues, and concludes with suggestions for possible research agendas. Urges students and researchers to be more actively critical of the assumptions and findings of these studies. (Author/IRT)
Magnetic MIMO Signal Processing and Optimization for Wireless Power Transfer
NASA Astrophysics Data System (ADS)
Yang, Gang; Moghadam, Mohammad R. Vedady; Zhang, Rui
2017-06-01
In magnetic resonant coupling (MRC) enabled multiple-input multiple-output (MIMO) wireless power transfer (WPT) systems, multiple transmitters (TXs) each with one single coil are used to enhance the efficiency of simultaneous power transfer to multiple single-coil receivers (RXs) by constructively combining their induced magnetic fields at the RXs, a technique termed "magnetic beamforming". In this paper, we study the optimal magnetic beamforming design in a multi-user MIMO MRC-WPT system. We introduce the multi-user power region that constitutes all the achievable power tuples for all RXs, subject to the given total power constraint over all TXs as well as their individual peak voltage and current constraints. We characterize each boundary point of the power region by maximizing the sum-power deliverable to all RXs subject to their minimum harvested power constraints. For the special case without the TX peak voltage and current constraints, we derive the optimal TX current allocation for the single-RX setup in closed-form as well as that for the multi-RX setup. In general, the problem is a non-convex quadratically constrained quadratic programming (QCQP), which is difficult to solve. For the case of one single RX, we show that the semidefinite relaxation (SDR) of the problem is tight. For the general case with multiple RXs, based on SDR we obtain two approximate solutions by applying time-sharing and randomization, respectively. Moreover, for practical implementation of magnetic beamforming, we propose a novel signal processing method to estimate the magnetic MIMO channel due to the mutual inductances between TXs and RXs. Numerical results show that our proposed magnetic channel estimation and adaptive beamforming schemes are practically effective, and can significantly improve the power transfer efficiency and multi-user performance trade-off in MIMO MRC-WPT systems.
Completion Design Considerations for a Horizontal Enhanced Geothermal System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olson, Jeffrey; Eustes, Alfred; Fleckenstein, William
2015-09-02
The petroleum industry has had considerable success in recent decades in developing unconventional shale plays using horizontal drilling and multi-zonal isolation and stimulation techniques to fracture tight formations to enable the commercial production of oil and gas. Similar well completions could be used in Enhanced Geothermal Systems (EGS) to create multiple fractures from horizontal wells. This study assesses whether well completion techniques used in the unconventional shale industry to create multi-stage fractures can be applied to an enhanced geothermal system, with a focus on the completion of the EGS injection well. This study assumes an Enhanced Geothermal System (EGS) consistingmore » of a central horizontal injection well flanked on each side by horizontal production wells, connected to the injection well by multiple fractures. The focus is on the design and completion of the horizontal well. For the purpose of developing design criteria, a reservoir temperature of 200 degrees C (392 degrees F) and an injection well flow rate of 87,000 barrels per day (160 kg/s), corresponding to production well flow rates of 43,500 barrels per day (80 kg/s) is assumed. The analysis found that 9-5/8 inches 53.5 pounds per foot (ppf) P110 casing string with premium connections meets all design criteria for the horizontal section of injection well. A P110 grade is fairly common and is often used in horizontal sections of shale development wells in petroleum operations. Next, several zonal isolation systems commonly used in the shale gas industry were evaluated. Three techniques were evaluated -- a 'plug and perf' design, a 'sand and perf' design, and a 'packer and port' design. A plug and perf system utilizes a cemented casing throughout the length of the injector wellbore. The sand and perf system is identical to the plug and perf system, but replaces packers with sand placed in the casing after stimulation to screen out the stimulated perforated zones and provide zonal isolation. The packer and port completion approach utilizes an open horizontal hole that zonally isolates areas through the use of external packers and a liner. A review of technologies used in these systems was performed to determine if commercially available equipment from the petroleum industry could be used at the temperatures, pressures, and sizes encountered in geothermal settings. The study found no major technical barriers to employing shale gas multi-zonal completion techniques in a horizontal well in a geothermal setting for EGS development. For all techniques considered, temperature limitations of equipment are a concern. Commercially available equipment designed to operate at the high temperatures encountered in geothermal systems are available, but is generally unproven for geothermal applications. Based on the study, further evaluation of adapting oil and gas completion techniques to EGS is warranted.« less
Space assembly fixtures and aids
NASA Technical Reports Server (NTRS)
Bloom, K. A.; Lillenas, A. N.
1980-01-01
Concepts and requirements for assembly fixtures and aids necessary for the assembly and maintenance of spare platforms were studied. Emphasis was placed on erectable and deployable type structures with the shuttle orbiter as the assembly base. Both single and multiple orbiter flight cases for the platform assembly were considered. Applicable space platform assembly studies were reviewed to provide a data base for establishing the assembly fixture and aids design requirements, assembly constraints, and the development of representative design concepts. Conclusions indicated that fixture requirements will vary with platform size. Larger platforms will require translation relative to the orbiter RMS working volume. The installation of platform payloads and subsystems (e.g., utility distribution) must also be considered in the specification of assembly fixtures and aids.
Patient perspectives on engagement in shared decision-making for asthma care.
Tapp, Hazel; Derkowski, Diane; Calvert, Melissa; Welch, Madelyn; Spencer, Sara
2017-06-01
Engagement of patient and advocacy group stakeholders is increasingly considered essential to meaningful outcomes research. Patient-centred research benefits from partnership formation between patients, clinicians and research team members. Here, we describe the rationale for engaging patients on a research team and a case study of patient engagement on an asthma shared decision-making study. Here, we describe a case study of patient engagement in outcomes research and examine the variety of roles patients are engaged in and the associated impact on the study. Patients assisted the project at various levels and were integrated into the research team by (i) advising on study development; (ii) assisting with design and usability of study materials, including the toolkit, patient surveys and dissemination strategies; and (iii) advocacy via membership in external disease-specific organizations and participating in outcomes research conferences. Patients were engaged both individually and as members of a patient advisory board. Primary lessons learned were the importance of building a trusting partnership with patients through understanding perspectives, being aware of clearly explaining patients' roles, research methods and jargon, providing training, listening to patients' needs and understanding what the partnership means from a patient perspective. For the case study described, patient engagement directly influenced multiple aspects of the study, including study design, implementation, data analysis and dissemination through incorporation of the patients' and caregivers' input and concerns. © The Author 2016. Published by Oxford University Press.
Visually Exploring Transportation Schedules.
Palomo, Cesar; Guo, Zhan; Silva, Cláudio T; Freire, Juliana
2016-01-01
Public transportation schedules are designed by agencies to optimize service quality under multiple constraints. However, real service usually deviates from the plan. Therefore, transportation analysts need to identify, compare and explain both eventual and systemic performance issues that must be addressed so that better timetables can be created. The purely statistical tools commonly used by analysts pose many difficulties due to the large number of attributes at trip- and station-level for planned and real service. Also challenging is the need for models at multiple scales to search for patterns at different times and stations, since analysts do not know exactly where or when relevant patterns might emerge and need to compute statistical summaries for multiple attributes at different granularities. To aid in this analysis, we worked in close collaboration with a transportation expert to design TR-EX, a visual exploration tool developed to identify, inspect and compare spatio-temporal patterns for planned and real transportation service. TR-EX combines two new visual encodings inspired by Marey's Train Schedule: Trips Explorer for trip-level analysis of frequency, deviation and speed; and Stops Explorer for station-level study of delay, wait time, reliability and performance deficiencies such as bunching. To tackle overplotting and to provide a robust representation for a large numbers of trips and stops at multiple scales, the system supports variable kernel bandwidths to achieve the level of detail required by users for different tasks. We justify our design decisions based on specific analysis needs of transportation analysts. We provide anecdotal evidence of the efficacy of TR-EX through a series of case studies that explore NYC subway service, which illustrate how TR-EX can be used to confirm hypotheses and derive new insights through visual exploration.
Advanced Vehicle Concepts and Implications for NextGen
NASA Technical Reports Server (NTRS)
Blake, Matt; Smith, Jim; Wright, Ken; Mediavilla Ricky; Kirby, Michelle; Pfaender, Holger; Clarke, John-Paul; Volovoi, Vitali; Dorbian, Christopher; Ashok, Akshay;
2010-01-01
This report presents the results of a major NASA study of advanced vehicle concepts and their implications for the Next Generation Air Transportation System (NextGen). Comprising the efforts of dozens of researchers at multiple institutions, the analyses presented here cover a broad range of topics including business-case development, vehicle design, avionics, procedure design, delay, safety, environmental impacts, and metrics. The study focuses on the following five new vehicle types: Cruise-efficient short takeoff and landing (CESTOL) vehicles Large commercial tiltrotor aircraft (LCTRs) Unmanned aircraft systems (UAS) Very light jets (VLJs) Supersonic transports (SST). The timeframe of the study spans the years 2025-2040, although some analyses are also presented for a 3X scenario that has roughly three times the number of flights as today. Full implementation of NextGen is assumed.
Wahi, Monika M; Parks, David V; Skeate, Robert C; Goldin, Steven B
2008-01-01
We conducted a reliability study comparing single data entry (SE) into a Microsoft Excel spreadsheet to entry using the existing forms (EF) feature of the Teleforms software system, in which optical character recognition is used to capture data off of paper forms designed in non-Teleforms software programs. We compared the transcription of data from multiple paper forms from over 100 research participants representing almost 20,000 data entry fields. Error rates for SE were significantly lower than those for EF, so we chose SE for data entry in our study. Data transcription strategies from paper to electronic format should be chosen based on evidence from formal evaluations, and their design should be contemplated during the paper forms development stage.
Wahi, Monika M.; Parks, David V.; Skeate, Robert C.; Goldin, Steven B.
2008-01-01
We conducted a reliability study comparing single data entry (SE) into a Microsoft Excel spreadsheet to entry using the existing forms (EF) feature of the Teleforms software system, in which optical character recognition is used to capture data off of paper forms designed in non-Teleforms software programs. We compared the transcription of data from multiple paper forms from over 100 research participants representing almost 20,000 data entry fields. Error rates for SE were significantly lower than those for EF, so we chose SE for data entry in our study. Data transcription strategies from paper to electronic format should be chosen based on evidence from formal evaluations, and their design should be contemplated during the paper forms development stage. PMID:18308994
Understanding genetics: Analysis of secondary students' conceptual status
NASA Astrophysics Data System (ADS)
Tsui, Chi-Yan; Treagust, David F.
2007-02-01
This article explores the conceptual change of students in Grades 10 and 12 in three Australian senior high schools when the teachers included computer multimedia to a greater or lesser extent in their teaching of a genetics course. The study, underpinned by a multidimensional conceptual-change framework, used an interpretive approach and a case-based design with multiple data collection methods. Over 4-8 weeks, the students learned genetics in classroom lessons that included BioLogica activities, which feature multiple representations. Results of the online tests and interview tasks revealed that most students improved their understanding of genetics as evidenced in the development of genetics reasoning. However, using Thorley's (1990) status analysis categories, a cross-case analysis of the gene conceptions of 9 of the 26 students interviewed indicated that only 4 students' postinstructional conceptions were intelligible-plausible-fruitful. Students' conceptual change was consistent with classroom teaching and learning. Findings suggested that multiple representations supported conceptual understanding of genetics but not in all students. It was also shown that status can be a viable hallmark enabling researchers to identify students' conceptual change that would otherwise be less accessible. Thorley's method for analyzing conceptual status is discussed.
Carcillo, Joseph A; Halstead, E Scott; Hall, Mark W; Nguyen, Trung C; Reeder, Ron; Aneja, Rajesh; Shakoory, Bita; Simon, Dennis
2017-06-01
We hypothesize that three inflammation pathobiology phenotypes are associated with increased inflammation, proclivity to develop features of macrophage activation syndrome, and multiple organ failure-related death in pediatric severe sepsis. Prospective cohort study comparing children with severe sepsis and any of three phenotypes: 1) immunoparalysis-associated multiple organ failure (whole blood ex vivo tumor necrosis factor response to endotoxin < 200 pg/mL), 2) thrombocytopenia-associated multiple organ failure (new onset thrombocytopenia with acute kidney injury and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 activity < 57%), and/or 3) sequential multiple organ failure with hepatobiliary dysfunction (respiratory distress followed by liver dysfunction with soluble Fas ligand > 200 pg/mL), to those without any of these phenotypes. Tertiary children's hospital PICU. One hundred consecutive severe sepsis admissions. Clinical data were recorded daily, and blood was collected twice weekly. Multiple organ failure developed in 75 cases and eight died. Multiple organ failure cases with any of the three inflammation phenotypes (n = 37) had higher inflammation (C-reactive protein, p = 0.009 and ferritin, p < 0.001) than multiple organ failure cases without any of these phenotypes (n = 38) or cases with only single organ failure (n = 25). Development of features of macrophage activation syndrome and death were more common among multiple organ failure cases with any of the phenotypes (macrophage activation syndrome: 10/37, 27%; death: 8/37, 22%) compared to multiple organ failure cases without any phenotype (macrophage activation syndrome: 1/38, 3%; p = 0.003 and death: 0/38, 0%; p = 0.002). Our approach to phenotype categorization remains hypothetical, and the phenotypes identified need to be confirmed in multicenter studies of pediatric multiple organ dysfunction syndrome.
A proposed study of multiple scattering through clouds up to 1 THz
NASA Technical Reports Server (NTRS)
Gerace, G. C.; Smith, E. K.
1992-01-01
A rigorous computation of the electromagnetic field scattered from an atmospheric liquid water cloud is proposed. The recent development of a fast recursive algorithm (Chew algorithm) for computing the fields scattered from numerous scatterers now makes a rigorous computation feasible. A method is presented for adapting this algorithm to a general case where there are an extremely large number of scatterers. It is also proposed to extend a new binary PAM channel coding technique (El-Khamy coding) to multiple levels with non-square pulse shapes. The Chew algorithm can be used to compute the transfer function of a cloud channel. Then the transfer function can be used to design an optimum El-Khamy code. In principle, these concepts can be applied directly to the realistic case of a time-varying cloud (adaptive channel coding and adaptive equalization). A brief review is included of some preliminary work on cloud dispersive effects on digital communication signals and on cloud liquid water spectra and correlations.
2013-01-01
Background Improving quality in children’s mental health and social service settings will require implementation strategies capable of moving effective treatments and other innovations (e.g., assessment tools) into routine care. It is likely that efforts to identify, develop, and refine implementation strategies will be more successful if they are informed by relevant stakeholders and are responsive to the strengths and limitations of the contexts and implementation processes identified in usual care settings. This study will describe: the types of implementation strategies used; how organizational leaders make decisions about what to implement and how to approach the implementation process; organizational stakeholders’ perceptions of different implementation strategies; and the potential influence of organizational culture and climate on implementation strategy selection, implementation decision-making, and stakeholders’ perceptions of implementation strategies. Methods/design This study is a mixed methods multiple case study of seven children’s social service organizations in one Midwestern city in the United States that compose the control group of a larger randomized controlled trial. Qualitative data will include semi-structured interviews with organizational leaders (e.g., CEOs/directors, clinical directors, program managers) and a review of documents (e.g., implementation and quality improvement plans, program manuals, etc.) that will shed light on implementation decision-making and specific implementation strategies that are used to implement new programs and practices. Additionally, focus groups with clinicians will explore their perceptions of a range of implementation strategies. This qualitative work will inform the development of a Web-based survey that will assess the perceived effectiveness, relative importance, acceptability, feasibility, and appropriateness of implementation strategies from the perspective of both clinicians and organizational leaders. Finally, the Organizational Social Context measure will be used to assess organizational culture and climate. Qualitative, quantitative, and mixed methods data will be analyzed and interpreted at the case level as well as across cases in order to highlight meaningful similarities, differences, and site-specific experiences. Discussion This study is designed to inform efforts to develop more effective implementation strategies by fully describing the implementation experiences of a sample of community-based organizations that provide mental health services to youth in one Midwestern city. PMID:23961701
Multiple regression for physiological data analysis: the problem of multicollinearity.
Slinker, B K; Glantz, S A
1985-07-01
Multiple linear regression, in which several predictor variables are related to a response variable, is a powerful statistical tool for gaining quantitative insight into complex in vivo physiological systems. For these insights to be correct, all predictor variables must be uncorrelated. However, in many physiological experiments the predictor variables cannot be precisely controlled and thus change in parallel (i.e., they are highly correlated). There is a redundancy of information about the response, a situation called multicollinearity, that leads to numerical problems in estimating the parameters in regression equations; the parameters are often of incorrect magnitude or sign or have large standard errors. Although multicollinearity can be avoided with good experimental design, not all interesting physiological questions can be studied without encountering multicollinearity. In these cases various ad hoc procedures have been proposed to mitigate multicollinearity. Although many of these procedures are controversial, they can be helpful in applying multiple linear regression to some physiological problems.
Mital, A
1999-01-01
Manual handling of materials continues to be a hazardous activity, leading to a very significant number of severe overexertion injuries. Designing jobs that are within the physical capabilities of workers is one approach ergonomists have adopted to redress this problem. As a result, several job design procedures have been developed over the years. However, these procedures are limited to designing or evaluating only pure lifting jobs or only the lifting aspect of a materials handling job. This paper describes a general procedure that may be used to design or analyse materials handling jobs that involve several different kinds of activities (e.g. lifting, lowering, carrying, pushing, etc). The job design/analysis procedure utilizes an elemental approach (breaking the job into elements) and relies on databases provided in A Guide to Manual Materials Handling to compute associated risk factors. The use of the procedure is demonstrated with the help of two case studies.
Creating targeted initial populations for genetic product searches in heterogeneous markets
NASA Astrophysics Data System (ADS)
Foster, Garrett; Turner, Callaway; Ferguson, Scott; Donndelinger, Joseph
2014-12-01
Genetic searches often use randomly generated initial populations to maximize diversity and enable a thorough sampling of the design space. While many of these initial configurations perform poorly, the trade-off between population diversity and solution quality is typically acceptable for small-scale problems. Navigating complex design spaces, however, often requires computationally intelligent approaches that improve solution quality. This article draws on research advances in market-based product design and heuristic optimization to strategically construct 'targeted' initial populations. Targeted initial designs are created using respondent-level part-worths estimated from discrete choice models. These designs are then integrated into a traditional genetic search. Two case study problems of differing complexity are presented to illustrate the benefits of this approach. In both problems, targeted populations lead to computational savings and product configurations with improved market share of preferences. Future research efforts to tailor this approach and extend it towards multiple objectives are also discussed.
Population Analysis: Communicating in Context
NASA Technical Reports Server (NTRS)
Rajulu, Sudhakar; Thaxton, Sherry
2008-01-01
Providing accommodation to a widely varying user population presents a challenge to engineers and designers. It is often even difficult to quantify who is accommodated and who is not accommodated by designs, especially for equipment with multiple critical anthropometric dimensions. An approach to communicating levels of accommodation referred to as population analysis applies existing human factors techniques in novel ways. This paper discusses the definition of population analysis as well as major applications and case studies. The major applications of population analysis consist of providing accommodation information for multivariate problems and enhancing the value of feedback from human-in-the-loop testing. The results of these analyses range from the provision of specific accommodation percentages of the user population to recommendations of design specifications based on quantitative data. Such feedback is invaluable to designers and results in the design of products that accommodate the intended user population.
PathCase-SB architecture and database design
2011-01-01
Background Integration of metabolic pathways resources and regulatory metabolic network models, and deploying new tools on the integrated platform can help perform more effective and more efficient systems biology research on understanding the regulation in metabolic networks. Therefore, the tasks of (a) integrating under a single database environment regulatory metabolic networks and existing models, and (b) building tools to help with modeling and analysis are desirable and intellectually challenging computational tasks. Description PathCase Systems Biology (PathCase-SB) is built and released. The PathCase-SB database provides data and API for multiple user interfaces and software tools. The current PathCase-SB system provides a database-enabled framework and web-based computational tools towards facilitating the development of kinetic models for biological systems. PathCase-SB aims to integrate data of selected biological data sources on the web (currently, BioModels database and KEGG), and to provide more powerful and/or new capabilities via the new web-based integrative framework. This paper describes architecture and database design issues encountered in PathCase-SB's design and implementation, and presents the current design of PathCase-SB's architecture and database. Conclusions PathCase-SB architecture and database provide a highly extensible and scalable environment with easy and fast (real-time) access to the data in the database. PathCase-SB itself is already being used by researchers across the world. PMID:22070889
Technical assistance for law-enforcement communications: Case study report
NASA Technical Reports Server (NTRS)
Reilly, N. B.; Mustain, J. A.
1979-01-01
Methods developed to improve police communications systems are described. Use of queueing analysis shows several ways of improving time of response to inquiries made from the field for license plate checks and for information on current wants and warrants, through a state multiple switcher network. Design criteria for more efficient centralized switching equipment are developed. A message load problem experienced in a dispatch center is analyzed, showing that communications could be improved by adding communications channels, not by adding people.
Baxter, Amanda J.; Hughes, Maria Celia; Kvaskoff, Marina; Siskind, Victor; Shekar, Sri; Aitken, Joanne F.; Green, Adele C.; Duffy, David L.; Hayward, Nicholas K.; Martin, Nicholas G.; Whiteman, David C.
2013-01-01
Cutaneous malignant melanoma (CMM) is a major health issue in Queensland, Australia which has the world’s highest incidence. Recent molecular and epidemiologic studies suggest that CMM arises through multiple etiological pathways involving gene-environment interactions. Understanding the potential mechanisms leading to CMM requires larger studies than those previously conducted. This article describes the design and baseline characteristics of Q-MEGA, the Queensland study of Melanoma: Environmental and Genetic Associations, which followed-up four population-based samples of CMM patients in Queensland, including children, adolescents, men aged over 50, and a large sample of adult cases and their families, including twins. Q-MEGA aims to investigate the roles of genetic and environmental factors, and their interaction, in the etiology of melanoma. 3,471 participants took part in the follow-up study and were administered a computer-assisted telephone interview in 2002–2005. Updated data on environmental and phenotypic risk factors, and 2,777 blood samples were collected from interviewed participants as well as a subset of relatives. This study provides a large and well-described population-based sample of CMM cases with follow-up data. Characteristics of the cases and repeatability of sun exposure and phenotype measures between the baseline and the follow-up surveys, from six to 17 years later, are also described. PMID:18361720
Tracking the Gender Pay Gap: A Case Study
ERIC Educational Resources Information Center
Travis, Cheryl B.; Gross, Louis J.; Johnson, Bruce A.
2009-01-01
This article provides a short introduction to standard considerations in the formal study of wages and illustrates the use of multiple regression and resampling simulation approaches in a case study of faculty salaries at one university. Multiple regression is especially beneficial where it provides information on strength of association, specific…
ERIC Educational Resources Information Center
Story, Julie A.
2014-01-01
The purpose of this qualitative multiple-case study was to explore academic leaders' experiences with the organizational elements of their own high school-college writing center collaborations. Conjoining theories framed this study: collaborative leadership theory, Kenneth Bruffee's notion of social constructionism and collaborative learning…
Distributed Leadership in Elementary Schools: An Exploratory Multiple Case Study
ERIC Educational Resources Information Center
Valdez, Vidal
2016-01-01
The purpose of this study was to explore distributed leadership and how leadership practices are actualized in three selected schools in Southern California. This qualitative, multiple case study used survey research and interviews to assess how distributed leadership was practiced in three selected elementary schools located within one school…
ERIC Educational Resources Information Center
Richards, Kathleen A.
2013-01-01
This multiple case study investigates the learning processes of postsecondary English literature graduates who teach composition to diverse student groups. Since the context of study in English literature graduate programs concentrates on literature and literary theory, the interest of this study examines how teachers learn to teach composition…
VAUD: A Visual Analysis Approach for Exploring Spatio-Temporal Urban Data.
Chen, Wei; Huang, Zhaosong; Wu, Feiran; Zhu, Minfeng; Guan, Huihua; Maciejewski, Ross
2017-10-02
Urban data is massive, heterogeneous, and spatio-temporal, posing a substantial challenge for visualization and analysis. In this paper, we design and implement a novel visual analytics approach, Visual Analyzer for Urban Data (VAUD), that supports the visualization, querying, and exploration of urban data. Our approach allows for cross-domain correlation from multiple data sources by leveraging spatial-temporal and social inter-connectedness features. Through our approach, the analyst is able to select, filter, aggregate across multiple data sources and extract information that would be hidden to a single data subset. To illustrate the effectiveness of our approach, we provide case studies on a real urban dataset that contains the cyber-, physical-, and socialinformation of 14 million citizens over 22 days.
Provident, Ingrid M; Colmer, Maria A
2013-01-01
A shortage of traditional medical fieldwork placements has been reported in the United States. Alternative settings are being sought to meet the Accreditation Standards for Level I fieldwork. This study was designed to examine and report the outcomes of an alternative pediatric camp setting, using a group model of supervision to fulfill the requirements for Level I fieldwork. Thirty-seven students from two Pennsylvania OT schools. Two cohorts of students were studied over a two year period using multiple methods of retrospective review and data collection. Students supervised in a group model experienced positive outcomes, including opportunities to deliver client centered care, and understanding the role of caregiving for children with disabilities. The use of a collaborative model of fieldwork education at a camp setting has resulted in a viable approach for the successful attainment of Level I fieldwork objectives for multiple students under a single supervisor.
Goicolea, Isabel; Coe, Anna-Britt; San Sebastián, Miguel; Hurtig, Anna-Karin
2017-08-01
Adolescent-Friendly Health Services (AFHSs) are those that are accessible, acceptable, equitable, appropriate and effective for different youth sub-populations. This study investigated the process through which four clinics in two countries - Peru and Ecuador - introduced, developed and sustained AFHSs. A multiple case study design was chosen, and data from each clinic were collected through document review, observations and informant interviews. National level data were also collected. Data were analysed following thematic analysis. The findings showed that the process of introducing, developing and sustaining AFHSs was long term, and required a creative team effort and collaboration between donors, public institutions and health providers. The motivation and external support was crucial to initiating and sustaining the implementation of AFHSs. Health facilities' transformation into AFHSs was linked to the broader organisation of country health systems, and the evolution of national adolescent health policies. In Peru, the centralised approach to AFHSs introduction facilitated the dissemination of a comprehensive national model to health facilities, but dependency on national directives made it more difficult to systemise them when ideological and organisational changes occurred. In Ecuador, a less centralised approach to introducing AFHSs made for easier integration of the AFHSs model.
Bortz, John; Shatz, Narkis
2011-04-01
The recently developed generalized functional method provides a means of designing nonimaging concentrators and luminaires for use with extended sources and receivers. We explore the mathematical relationships between optical designs produced using the generalized functional method and edge-ray, aplanatic, and simultaneous multiple surface (SMS) designs. Edge-ray and dual-surface aplanatic designs are shown to be special cases of generalized functional designs. In addition, it is shown that dual-surface SMS designs are closely related to generalized functional designs and that certain computational advantages accrue when the two design methods are combined. A number of examples are provided. © 2011 Optical Society of America
Walshe, Catherine
2011-12-01
Complex, incrementally changing, context dependent and variable palliative care services are difficult to evaluate. Case study research strategies may have potential to contribute to evaluating such complex interventions, and to develop this field of evaluation research. This paper explores definitions of case study (as a unit of study, a process, and a product) and examines the features of case study research strategies which are thought to confer benefits for the evaluation of complex interventions in palliative care settings. Ten features of case study that are thought to be beneficial in evaluating complex interventions in palliative care are discussed, drawing from exemplars of research in this field. Important features are related to a longitudinal approach, triangulation, purposive instance selection, comprehensive approach, multiple data sources, flexibility, concurrent data collection and analysis, search for proving-disproving evidence, pattern matching techniques and an engaging narrative. The limitations of case study approaches are discussed including the potential for subjectivity and their complex, time consuming and potentially expensive nature. Case study research strategies have great potential in evaluating complex interventions in palliative care settings. Three key features need to be exploited to develop this field: case selection, longitudinal designs, and the use of rival hypotheses. In particular, case study should be used in situations where there is interplay and interdependency between the intervention and its context, such that it is difficult to define or find relevant comparisons.
Historical development of administration architecture in Malaysia (15th-21st century)
NASA Astrophysics Data System (ADS)
Mohidin, H. H. B.; Ismail, A. S.
2014-02-01
The main purpose of this paper is to document the development of the state administration building in Malaysia before and after the independence era, in relation to the evolutionary period of Malaysia's political, social and economic history. Multiple case study approach [19] is applied by referring to six prominent case studies to represent state administrative buildings from various phases of Malaysian history beginning from 14th century to 21st century as exemplar. Since this paper formulates new ways to approach and describes state administrative building design and factors that influence them, it uses interpretivism paradigm and (semiotics) as methodological approach to study the relationship between the building design and contextual elements. This paper, therefore, offers new insights, which not only add to knowledge in this field by widening and strengthening the understanding of state administrative architecture in Malaysia, but also are valuable for range of associated fields including architectural semiotics and non verbal communication. This is because this paper reveals deep understandings of the built form and material environment operating as a sign in a cultural and social context.
Sample size determination for equivalence assessment with multiple endpoints.
Sun, Anna; Dong, Xiaoyu; Tsong, Yi
2014-01-01
Equivalence assessment between a reference and test treatment is often conducted by two one-sided tests (TOST). The corresponding power function and sample size determination can be derived from a joint distribution of the sample mean and sample variance. When an equivalence trial is designed with multiple endpoints, it often involves several sets of two one-sided tests. A naive approach for sample size determination in this case would select the largest sample size required for each endpoint. However, such a method ignores the correlation among endpoints. With the objective to reject all endpoints and when the endpoints are uncorrelated, the power function is the production of all power functions for individual endpoints. With correlated endpoints, the sample size and power should be adjusted for such a correlation. In this article, we propose the exact power function for the equivalence test with multiple endpoints adjusted for correlation under both crossover and parallel designs. We further discuss the differences in sample size for the naive method without and with correlation adjusted methods and illustrate with an in vivo bioequivalence crossover study with area under the curve (AUC) and maximum concentration (Cmax) as the two endpoints.
Browne, Annette J; Varcoe, Colleen; Ford-Gilboe, Marilyn; Wathen, C Nadine
2015-12-14
The primary health care (PHC) sector is increasingly relevant as a site for population health interventions, particularly in relation to marginalized groups, where the greatest gains in health status can be achieved. The purpose of this paper is to provide an overview of an innovative multi-component, organizational-level intervention designed to enhance the capacity of PHC clinics to provide equity-oriented care, particularly for marginalized populations. The intervention, known as EQUIP, is being implemented in Canada in four diverse PHC clinics serving populations who are impacted by structural inequities. These PHC clinics serve as case studies for the implementation and evaluation of the EQUIP intervention. We discuss the evidence and theory that provide the basis for the intervention, describe the intervention components, and discuss the methods used to evaluate the implementation and impact of the intervention in diverse contexts. Research and theory related to equity-oriented care, and complexity theory, are central to the design of the EQUIP intervention. The intervention aims to enhance capacity for equity-oriented care at the staff level, and at the organizational level (i.e., policy and operations) and is novel in its dual focus on: (a) Staff education: using standardized educational models and integration strategies to enhance staff knowledge, attitudes and practices related to equity-oriented care in general, and cultural safety, and trauma- and violence-informed care in particular, and; (b) Organizational integration and tailoring: using a participatory approach, practice facilitation, and catalyst grants to foster shifts in organizational structures, practices and policies to enhance the capacity to deliver equity-oriented care, improve processes of care, and shift key client outcomes. Using a mixed methods, multiple case-study design, we are examining the impact of the intervention in enhancing staff knowledge, attitudes and practices; improving processes of care; shifting organizational policies and structures; and improving selected client outcomes. The multiple case study design provides an ideal opportunity to study the contextual factors shaping the implementation, uptake and impact of our tailored intervention within diverse PHC settings. The EQUIP intervention illustrates the complexities involved in enhancing the PHC sector's capacity to provide equity-oriented care in real world clinical contexts.
Veronese, Nicola; Solmi, Marco; Luchini, Claudio; Lu, Ru-Band; Stubbs, Brendon; Zaninotto, Leonardo; Correll, Christoph U
2016-06-01
Acetylcholinesterase inhibitors (AceI) and memantine might prove useful in bipolar disorder (BD) given their neuroprotective and pro-cognitive effects, as highlighted by several case reports. We aimed to systematically review the efficacy and safety of AceI and memantine across multiple outcome dimensions in BD. Systematic PubMed and SCOPUS search until 04/17/2015 without language restrictions. Included were randomized controlled trials (RCTs), open label studies and case series of AceI or memantine in BD patients reporting quantitative data on depression, mania, psychotic symptoms, global functioning, or cognitive performance. We summarized results using a best-evidence based synthesis. Out of 214 hits, 12 studies (RCTs=5, other designs=7, total n=422) were included. Donepezil (studies=5; treated=102 vs. placebo=21): there was strong evidence for no effect on mania and psychotic symptoms; low evidence indicating no effect on depression. Galantamine (studies=3; treated=21 vs. controls=20) (placebo=10, healthy subjects=10): there was strong evidence for no effect on mania; moderate evidence for no effect on depression; low evidence for no effect on global functioning. Memantine (studies=4; treated=152 vs. placebo=88): there was conflicting evidence regarding efficacy for mania, depression and global functioning. Paucity of RCTs; small sample size studies; heterogeneous design, outcome and patient characteristics. There is limited but converging evidence of no effect of AceI in BD, and conflicting evidence about memantine in BD. Too few studies of mostly medium/low quality and lacking sufficient numbers of patients in specific mood states, especially mania, contributed data, focusing solely on short-term/medium-term treatment, necessitating additional high-quality research to yield more definite results. Copyright © 2016 Elsevier B.V. All rights reserved.
A Case Study of Learning, Motivation, and Performance Strategies for Teaching and Coaching CDE Teams
ERIC Educational Resources Information Center
Ball, Anna; Bowling, Amanda; Bird, Will
2016-01-01
This intrinsic case study examined the case of students on CDE (Career Development Event) teams preparing for state competitive events and the teacher preparing them in a school with a previous exemplary track record of winning multiple state and national career development events. The students were interviewed multiple times during the 16-week…
Estimation of a Nonlinear Intervention Phase Trajectory for Multiple-Baseline Design Data
ERIC Educational Resources Information Center
Hembry, Ian; Bunuan, Rommel; Beretvas, S. Natasha; Ferron, John M.; Van den Noortgate, Wim
2015-01-01
A multilevel logistic model for estimating a nonlinear trajectory in a multiple-baseline design is introduced. The model is applied to data from a real multiple-baseline design study to demonstrate interpretation of relevant parameters. A simple change-in-levels (?"Levels") model and a model involving a quadratic function…
ERIC Educational Resources Information Center
Sheffield, Caroline
2011-01-01
This mixed methods multiple case study explored middle school social studies teachers' instructional use of digital technology at three suburban middle schools This mixed methods, multiple-case study explored middle school social studies teachers' instructional use of digital technology at three suburban middle schools in a large Florida school…
Handley, Margaret A; Schillinger, Dean; Shiboski, Stephen
2011-01-01
Although randomized controlled trials are often a gold standard for determining intervention effects, in the area of practice-based research (PBR), there are many situations in which individual randomization is not possible. Alternative approaches to evaluating interventions have received increased attention, particularly those that can retain elements of randomization such that they can be considered "controlled" trials. Methodological design elements and practical implementation considerations for two quasi-experimental design approaches that have considerable promise in PBR settings--the stepped-wedge design, and a variant of this design, a wait-list cross-over design, are presented along with a case study from a recent PBR intervention for patients with diabetes. PBR-relevant design features include: creation of a cohort over time that collects control data but allows all participants (clusters or patients) to receive the intervention; staggered introduction of clusters; multiple data collection points; and one-way cross-over into the intervention arm. Practical considerations include: randomization versus stratification, training run in phases; and extended time period for overall study completion. Several design features of practice based research studies can be adapted to local circumstances yet retain elements to improve methodological rigor. Studies that utilize these methods, such as the stepped-wedge design and the wait-list cross-over design, can increase the evidence base for controlled studies conducted within the complex environment of PBR.
DEVELOPING A VACCINE AGAINST MULTIPLE PSYCHOACTIVE TARGETS: A CASE STUDY OF HEROIN
Stowe, G. Neil; Schlosburg, Joel E.; Vendruscolo, Leandro F.; Edwards, Scott; Misra, Kaushik K.; Schulteis, Gery; Zakhari, Joseph S.; Koob, George F.; Janda, Kim D.
2012-01-01
Heroin addiction is a wide-reaching problem with a spectrum of damaging social consequences. Currently approved heroin addiction medications include drugs that bind at the same receptors (e.g. opioid receptors) occupied by heroin and/or its metabolites in the brain, but undesired side effects of these treatments, maintenance dependence and relapse to drug taking remains problematic. A vaccine capable of blocking heroin’s effects could provide an economical, long-lasting and sustainable adjunct to heroin addiction therapy without the side effects associated with available treatment options. Heroin, however, presents a particularly challenging vaccine target as it is metabolized to multiple psychoactive molecules of differing lipophilicity, with differing abilities to cross the blood brain barrier. In this review, we discuss the opiate scaffolding and hapten design considerations to confer immunogenicity as well as the specificity of the immune response towards structurally similar opiates. In addition, we detail different strategies employed in the design of immunoconjugates for a vaccine-based therapy for heroin addiction treatment. PMID:22229311
Learning from Comparing Multiple Examples: On the Dilemma of "Similar" or "Different"
ERIC Educational Resources Information Center
Guo, Jian-Peng; Pang, Ming Fai; Yang, Ling-Yan; Ding, Yi
2012-01-01
Although researchers have demonstrated that studying multiple examples is more effective than studying one example to facilitate learning, the principles found in the literature for designing multiple examples remain ambiguous. This paper reviews variation theory research on example design which sheds light on unclear issues regarding the effects…
Elementary students' engagement in failure-prone engineering design tasks
NASA Astrophysics Data System (ADS)
Andrews, Chelsea Joy
Although engineering education has been practiced at the undergraduate level for over a century, only fairly recently has the field broadened to include the elementary level; the pre-college division of the American Society of Engineering Education was established in 2003. As a result, while recent education standards require engineering in elementary schools, current studies are still filling in basic research on how best to design and implement elementary engineering activities. One area in need of investigation is how students engage with physical failure in design tasks. In this dissertation, I explore how upper elementary students engage in failure-prone engineering design tasks in an out-of-school environment. In a series of three empirical case studies, I look closely at how students evaluate failed tests and decide on changes to their design constructions, how their reasoning evolves as they repeatedly encounter physical failure, and how students and facilitators co-construct testing norms where repetitive failure is manageable. I also briefly investigate how students' engagement differs in a task that features near-immediate success. By closely examining student groups' discourse and their interactions with their design constructions, I found that these students: are able to engage in iteration and see failure-as-feedback with minimal externally-imposed structure; seem to be designing in a more sophisticated manner, attending to multiple causal factors, after experiencing repetitive failure; and are able to manage the stress and frustration of repetitive failure, provided the co-constructed testing norms of the workshop environment are supportive of failure management. These results have both pedagogical implications, in terms of how to create and facilitate design tasks, and methodological implications--namely, I highlight the particular insights afforded by a case study approach for analyzing engagement in design tasks.
Estimating open population site occupancy from presence-absence data lacking the robust design.
Dail, D; Madsen, L
2013-03-01
Many animal monitoring studies seek to estimate the proportion of a study area occupied by a target population. The study area is divided into spatially distinct sites where the detected presence or absence of the population is recorded, and this is repeated in time for multiple seasons. However, when occupied sites are detected with probability p < 1, the lack of a detection does not imply lack of occupancy. MacKenzie et al. (2003, Ecology 84, 2200-2207) developed a multiseason model for estimating seasonal site occupancy (ψt ) while accounting for unknown p. Their model performs well when observations are collected according to the robust design, where multiple sampling occasions occur during each season; the repeated sampling aids in the estimation p. However, their model does not perform as well when the robust design is lacking. In this paper, we propose an alternative likelihood model that yields improved seasonal estimates of p and Ψt in the absence of the robust design. We construct the marginal likelihood of the observed data by conditioning on, and summing out, the latent number of occupied sites during each season. A simulation study shows that in cases without the robust design, the proposed model estimates p with less bias than the MacKenzie et al. model and hence improves the estimates of Ψt . We apply both models to a data set consisting of repeated presence-absence observations of American robins (Turdus migratorius) with yearly survey periods. The two models are compared to a third estimator available when the repeated counts (from the same study) are considered, with the proposed model yielding estimates of Ψt closest to estimates from the point count model. Copyright © 2013, The International Biometric Society.
Xu, Xiaojing; Bao, Lingyun; Tan, Yanjuan; Zhu, Luoxi; Kong, Fanlei; Wang, Wei
2018-05-28
The objective of our study was to assess, in a reader study, radiologists' performance in interpretation of automated breast volume scanner (ABVS) images with the aid of a computer-aided detection (CADe) system. Our study is a retrospective observer study with the purpose of investigating the effectiveness of using a CADe system as an aid for radiologists in interpretation of ABVS images. The multiple-reader, multiple-case study was designed to compare the diagnostic performance of radiologists with and without CADe. The study included 1000 cases selected from ABVS examinations in our institution in 2012. Among those cases were 206 malignant, 486 benign and 308 normal cases. The cancer cases were consecutive; the benign and normal cases were randomly selected. All malignant and benign cases were confirmed by biopsy or surgery, and normal cases were confirmed by 2-y follow-up. Reader performance was compared in terms of area under the receiver operating characteristic curve, sensitivity and specificity. Additionally, the reading time per case for each reader was recorded. Nine radiologists from our institution participated in the study. Three had more than 8 y of ultrasound experience and more than 4 y of ABVS experience (group A); 3 had more than 5 y of ultrasound experience (group B), and 3 had more than 1 y of ultrasound experience (group C). Both group B and group C had no ABVS experience. The CADe system used was the QVCAD System (QView Medical, Inc., Los Altos, CA, USA). It is designed to aid radiologists in searching for suspicious areas in ABVS images. CADe results are presented to the reader simultaneously with the ABVS images; that is, the radiologists read the ABVS images concurrently with the CADe results. The cases were randomly assigned for each reader into two equal-size groups, 1 and 2. Initially the readers read their group 1 cases with the aid of CADe and their group 2 cases without CADe. After a 1-mo washout period, they re-read their group 1 cases without CADe and their group 2 cases with CADe. The areas under the receiver operating characteristic curves of all readers were 0.784 for reading with CADe and 0.747 without CADe. Areas under the curves with and without CADe were 0.833 and 0.829 for group A, 0.757 and 0.696 for group B and 0.759 and 0.718 for group C. All differences in areas under the curve were statistically significant (p <0.05), except that for group A. The average reading time was 9.3% (p < < 0.05) faster with CADe for all readers. In summary, CADe improves radiologist performance with respect to both accuracy and reading time for the detection of breast cancer using the ABVS, with the greater benefit for those inexperienced with ABVS. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.
SwaMURAy - Swapping Memory Unit for Radio Astronomy
NASA Astrophysics Data System (ADS)
Winberg, Simon
2016-03-01
This paper concerns design and performance testing of an HDL module called SwaMURAy that is a configurable, high-speed data sequencing and flow control module serving as an intermediary between data acquisition and subsequent processing stages. While a FIFO suffices for many applications, our case needed a more elaborate solution to overcome legacy design limitations. The SwaMURAy is designed around a system where a block of sampled data is acquired at a fast rate and is then distributed among multiple processing paths to achieve a desired overall processing rate. This architecture provides an effective design pattern around which various software defined radio (SDR) and radio astronomy applications can be built. This solution was partly in response to legacy design restrictions of the SDR platform we used, a difficulty likely experienced by many developers whereby new sampling peripherals are inhibited by legacy characteristics of an underlying reconfigurable platform. Our SDR platform had a planned lifetime of at least five years as a complete redesign and refabrication would be too costly. While the SwaMURAy overcame some performance problems, other problems arose. This paper overviews the SwaMURAy design, performance improvements achieved in an SDR case study, and discusses remaining limitations and workarounds we expect will achieve further improvements.
NASA Technical Reports Server (NTRS)
Feiveson, Alan H.; Ploutz-Snyder, Robert; Fiedler, James
2011-01-01
In their 2009 Annals of Statistics paper, Gavrilov, Benjamini, and Sarkar report the results of a simulation assessing the robustness of their adaptive step-down procedure (GBS) for controlling the false discovery rate (FDR) when normally distributed test statistics are serially correlated. In this study we extend the investigation to the case of multiple comparisons involving correlated non-central t-statistics, in particular when several treatments or time periods are being compared to a control in a repeated-measures design with many dependent outcome measures. In addition, we consider several dependence structures other than serial correlation and illustrate how the FDR depends on the interaction between effect size and the type of correlation structure as indexed by Foerstner s distance metric from an identity. The relationship between the correlation matrix R of the original dependent variables and R, the correlation matrix of associated t-statistics is also studied. In general R depends not only on R, but also on sample size and the signed effect sizes for the multiple comparisons.
Spontaneous abortion in multiple pregnancy: focus on fetal pathology.
Joó, József Gábor; Csaba, Ákos; Szigeti, Zsanett; Rigó, János
2012-08-15
Multiple pregnancy with its wide array of medical consequences poses an important condition during pregnancy. We performed perinatal autopsy in 49 cases of spontaneous abortion resulting from multiple pregnancies during the study period. Twenty-seven of the 44 twin pregnancies ending in miscarriage were conceived naturally, whereas 17 were conceived through assisted reproductive techniques. Each of the 5 triplet pregnancies ending in miscarriage was conceived through assisted reproductive techniques. There was a positive history of miscarriage in 22.4% of the cases. Monochorial placentation occurred more commonly in multiple pregnancies terminating with miscarriage than in multiple pregnancies without miscarriage. A fetal congenital malformation was found in 8 cases. Three of these cases were conceived through assisted reproductive techniques, and 5 were conceived naturally. Miscarriage was due to intrauterine infection in 36% of the cases. Our study confirms that spontaneous abortion is more common in multiple than in singleton pregnancies. Monochorial placentation predicted a higher fetal morbidity and mortality. In pregnancies where all fetuses were of male gender, miscarriage was more common than in pregnancies where all fetuses were female. Assisted reproductive techniques do not predispose to the development of fetal malformations. Copyright © 2012 Elsevier GmbH. All rights reserved.
Multiple Lower Extremity Mononeuropathies by Segmental Schwannomatosis: A Case Report
Kwon, Na Yeon; Oh, Hyun-Mi
2015-01-01
Schwannoma is an encapsulated nerve sheath tumor that is distinct from neurofibromatosis. It is defined as the occurrence of multiple schwannomas without any bilateral vestibular schwannomas. A 46-year-old man with multiple schwannomas involving peripheral nerves of the ipsilateral lower extremity presented with neurologic symptoms. Electrodiagnostic studies revealed multiple mononeuropathies involving the left sciatic, common peroneal, tibial, femoral and superior gluteal nerves. Histologic findings confirmed the diagnosis of schwannoma. We reported this rare case of segmental schwannomatosis that presented with neurologic symptoms including motor weakness, which was confirmed as multiple mononeuropathies by electrodiagnostic studies. PMID:26605183
Multiple Lower Extremity Mononeuropathies by Segmental Schwannomatosis: A Case Report.
Kwon, Na Yeon; Oh, Hyun-Mi; Ko, Young Jin
2015-10-01
Schwannoma is an encapsulated nerve sheath tumor that is distinct from neurofibromatosis. It is defined as the occurrence of multiple schwannomas without any bilateral vestibular schwannomas. A 46-year-old man with multiple schwannomas involving peripheral nerves of the ipsilateral lower extremity presented with neurologic symptoms. Electrodiagnostic studies revealed multiple mononeuropathies involving the left sciatic, common peroneal, tibial, femoral and superior gluteal nerves. Histologic findings confirmed the diagnosis of schwannoma. We reported this rare case of segmental schwannomatosis that presented with neurologic symptoms including motor weakness, which was confirmed as multiple mononeuropathies by electrodiagnostic studies.
Multiple magnet ingestion: is there a role for early surgical intervention?
Salimi, Amrollah; Kooraki, Soheil; Esfahani, Shadi Abdar; Mehdizadeh, Mehrzad
2012-01-01
Children often swallow foreign bodies. Multiple magnet ingestion is rare, but can result in serious complications. This study presents three unique cases of multiple magnet ingestion: one case an 8-year-old boy with multiple magnet ingestion resulting in gastric obstruction and the other two cases with intestinal perforations due to multiple magnet intake. History and physical examination are unreliable in children who swallow multiple magnets. Sometimes radiological findings are not conclusive, whether one magnet is swallowed or more. If magnets are not moved in sequential radiology images, we recommend early surgical intervention before gastrointestinal complications develop. Toy companies, parents, physicians, and radiologists should be warned about the potential complications of such toys.
Knowledge modeling tool for evidence-based design.
Durmisevic, Sanja; Ciftcioglu, Ozer
2010-01-01
The aim of this study is to take evidence-based design (EBD) to the next level by activating available knowledge, integrating new knowledge, and combining them for more efficient use by the planning and design community. This article outlines a framework for a performance-based measurement tool that can provide the necessary decision support during the design or evaluation of a healthcare environment by estimating the overall design performance of multiple variables. New knowledge in EBD adds continuously to complexity (the "information explosion"), and it becomes impossible to consider all aspects (design features) at the same time, much less their impact on final building performance. How can existing knowledge and the information explosion in healthcare-specifically the domain of EBD-be rendered manageable? Is it feasible to create a computational model that considers many design features and deals with them in an integrated way, rather than one at a time? The found evidence is structured and readied for computation through a "fuzzification" process. The weights are calculated using an analytical hierarchy process. Actual knowledge modeling is accomplished through a fuzzy neural tree structure. The impact of all inputs on the outcome-in this case, patient recovery-is calculated using sensitivity analysis. Finally, the added value of the model is discussed using a hypothetical case study of a patient room. The proposed model can deal with the complexities of various aspects and the relationships among variables in a coordinated way, allowing existing and new pieces of evidence to be integrated in a knowledge tree structure that facilitates understanding of the effects of various design interventions on overall design performance.
Inquiry-based Science Instruction in High School Biology Courses: A Multiple Case Study
NASA Astrophysics Data System (ADS)
Aso, Eze
A lack of research exists about how secondary school science teachers use inquiry-based instruction to improve student learning. The purpose of this qualitative study was to explore how science teachers used inquiry-based instruction to improve student learning in high school biology courses. The conceptual framework was based on Banchi and Bell's model of increasing levels of complexity for inquiry-based instruction. A multiple case study research design was conducted of biology programs at 3 high schools in an urban school district in the northeastern region of the United States. Participants included 2 biology teachers from each of the 3 high schools. Data were collected from individual interviews with biology teachers, observations of lessons in biology, and documents related to state standards, assessments, and professional development. The first level of data analysis involved coding and categorizing the interview and observation data. A content analysis was used for the documents. The second level of data analysis involved examining data across all sources and all cases for themes and discrepancies. According to study findings, biology teachers used confirmation, structure, and guided inquiry to improve student learning. However, they found open inquiry challenging and frustrating to implement because professional development about scaffolding of instruction over time was needed, and students' reading and writing skills needed to improve. This study contributes to positive social change by providing educators and researchers with a deeper understanding about how to scaffold levels of inquiry-based science instruction in order to help students become scientifically literate citizens.
Development of a High-Throughput Ion-Exchange Resin Characterization Workflow.
Liu, Chun; Dermody, Daniel; Harris, Keith; Boomgaard, Thomas; Sweeney, Jeff; Gisch, Daryl; Goltz, Bob
2017-06-12
A novel high-throughout (HTR) ion-exchange (IEX) resin workflow has been developed for characterizing ion exchange equilibrium of commercial and experimental IEX resins against a range of different applications where water environment differs from site to site. Because of its much higher throughput, design of experiment (DOE) methodology can be easily applied for studying the effects of multiple factors on resin performance. Two case studies will be presented to illustrate the efficacy of the combined HTR workflow and DOE method. In case study one, a series of anion exchange resins have been screened for selective removal of NO 3 - and NO 2 - in water environments consisting of multiple other anions, varied pH, and ionic strength. The response surface model (RSM) is developed to statistically correlate the resin performance with the water composition and predict the best resin candidate. In case study two, the same HTR workflow and DOE method have been applied for screening different cation exchange resins in terms of the selective removal of Mg 2+ , Ca 2+ , and Ba 2+ from high total dissolved salt (TDS) water. A master DOE model including all of the cation exchange resins is created to predict divalent cation removal by different IEX resins under specific conditions, from which the best resin candidates can be identified. The successful adoption of HTR workflow and DOE method for studying the ion exchange of IEX resins can significantly reduce the resources and time to address industry and application needs.
Multiple comparisons in drug efficacy studies: scientific or marketing principles?
Leo, Jonathan
2004-01-01
When researchers design an experiment to compare a given medication to another medication, a behavioral therapy, or a placebo, the experiment often involves numerous comparisons. For instance, there may be several different evaluation methods, raters, and time points. Although scientifically justified, such comparisons can be abused in the interests of drug marketing. This article provides two recent examples of such questionable practices. The first involves the case of the arthritis drug celecoxib (Celebrex), where the study lasted 12 months but the authors only presented 6 months of data. The second case involves the NIMH Multimodal Treatment Study (MTA) study evaluating the efficacy of stimulant medication for attention-deficit hyperactivity disorder where ratings made by several groups are reported in contradictory fashion. The MTA authors have not clarified the confusion, at least in print, suggesting that the actual findings of the study may have played little role in the authors' reported conclusions.
Patient safety challenges in a case study hospital--of relevance for transfusion processes?
Aase, Karina; Høyland, Sindre; Olsen, Espen; Wiig, Siri; Nilsen, Stein Tore
2008-10-01
The paper reports results from a research project with the objective of studying patient safety, and relates the finding to safety issues within transfusion medicine. The background is an increased focus on undesired events related to diagnosis, medication, and patient treatment in general in the healthcare sector. The study is designed as a case study within a regional Norwegian hospital conducting specialised health care services. The study includes multiple methods such as interviews, document analysis, analysis of error reports, and a questionnaire survey. Results show that the challenges for improved patient safety, based on employees' perceptions, are hospital management support, reporting of accidents/incidents, and collaboration across hospital units. Several of these generic safety challenges are also found to be of relevance for a hospital's transfusion service. Positive patient safety factors are identified as teamwork within hospital units, a non-punitive response to errors, and unit manager's actions promoting safety.
[Patient-related complexity in nursing care - Collective case studies in the acute care hospital].
Gurtner, Caroline; Spirig, Rebecca; Staudacher, Diana; Huber, Evelyn
2018-06-04
Patient-related complexity in nursing care - Collective case studies in the acute care hospital Abstract. Patient-related complexity of nursing is defined by the three characteristics "instability", "uncertainty", and "variability". Complexity increased in the past years, due to reduced hospital length of stay and a growing number of patients with chronic and multiple diseases. We investigated the phenomenon of patient-related complexity from the point of view of nurses and clinical nurse specialists in an acute care hospital. In the context of a collective case study design, nurses and clinical nurse specialists assessed the complexity of nursing situations with a questionnaire. Subsequently, we interviewed nurses and clinical nurse specialists about their evaluation of patient-related complexity. In a within-case-analysis we summarized data inductively to create case narratives. By means of a cross-case-analysis we compared the cases with regard to deductively derived characteristics. The four cases exemplarily showed that the degree of complexity depends on the controllability and predictability of clinical problems. Additionally, complexity increases or decreases, according to patients' individual resources. Complex patient situations demand professional expertise, experience, communicative competencies and the ability for reflection. Beginner nurses would benefit from support and advice by experienced nurses to develop these skills.
Wells, Stewart; Bullen, Chris
2008-01-01
This article describes the near failure of an information technology (IT) system designed to support a government-funded, primary care-based hepatitis B screening program in New Zealand. Qualitative methods were used to collect data and construct an explanatory model. Multiple incorrect assumptions were made about participants, primary care workflows and IT capacity, software vendor user knowledge, and the health IT infrastructure. Political factors delayed system development and it was implemented untested, almost failing. An intensive rescue strategy included system modifications, relaxation of data validity rules, close engagement with software vendors, and provision of intensive on-site user support. This case study demonstrates that consideration of the social, political, technological, and health care contexts is important for successful implementation of public health informatics projects.
Dynamics of Implementation and Maintenance of Organizational Health Interventions
Rahmandad, Hazhir; Bullock, Sally Lawrence; Ammerman, Alice
2017-01-01
In this study, we present case studies to explore the dynamics of implementation and maintenance of health interventions. We analyze how specific interventions are built and eroded, how the building and erosion mechanisms are interconnected, and why we can see significantly different erosion rates across otherwise similar organizations. We use multiple comparative obesity prevention case studies to provide empirical information on the mechanisms of interest, and use qualitative systems modeling to integrate our evolving understanding into an internally consistent and transparent theory of the phenomenon. Our preliminary results identify reinforcing feedback mechanisms, including design of organizational processes, motivation of stakeholders, and communication among stakeholders, which influence implementation and maintenance of intervention components. Over time, these feedback mechanisms may drive a wedge between otherwise similar organizations, leading to distinct configurations of implementation and maintenance processes. PMID:28809807
Stochastic Methods for Aircraft Design
NASA Technical Reports Server (NTRS)
Pelz, Richard B.; Ogot, Madara
1998-01-01
The global stochastic optimization method, simulated annealing (SA), was adapted and applied to various problems in aircraft design. The research was aimed at overcoming the problem of finding an optimal design in a space with multiple minima and roughness ubiquitous to numerically generated nonlinear objective functions. SA was modified to reduce the number of objective function evaluations for an optimal design, historically the main criticism of stochastic methods. SA was applied to many CFD/MDO problems including: low sonic-boom bodies, minimum drag on supersonic fore-bodies, minimum drag on supersonic aeroelastic fore-bodies, minimum drag on HSCT aeroelastic wings, FLOPS preliminary design code, another preliminary aircraft design study with vortex lattice aerodynamics, HSR complete aircraft aerodynamics. In every case, SA provided a simple, robust and reliable optimization method which found optimal designs in order 100 objective function evaluations. Perhaps most importantly, from this academic/industrial project, technology has been successfully transferred; this method is the method of choice for optimization problems at Northrop Grumman.
Ultrasound image filtering using the mutiplicative model
NASA Astrophysics Data System (ADS)
Navarrete, Hugo; Frery, Alejandro C.; Sanchez, Fermin; Anto, Joan
2002-04-01
Ultrasound images, as a special case of coherent images, are normally corrupted with multiplicative noise i.e. speckle noise. Speckle noise reduction is a difficult task due to its multiplicative nature, but good statistical models of speckle formation are useful to design adaptive speckle reduction filters. In this article a new statistical model, emerging from the Multiplicative Model framework, is presented and compared to previous models (Rayleigh, Rice and K laws). It is shown that the proposed model gives the best performance when modeling the statistics of ultrasound images. Finally, the parameters of the model can be used to quantify the extent of speckle formation; this quantification is applied to adaptive speckle reduction filter design. The effectiveness of the filter is demonstrated on typical in-vivo log-compressed B-scan images obtained by a clinical ultrasound system.
Experience with Using Multiple Types of Visual Educational Tools during Problem-Based Learning.
Kang, Bong Jin
2012-06-01
This study describes the experience of using multiple types of visual educational tools in the setting of problem-based learning (PBL). The author intends to demonstrate their roles in diverse and efficient ways of clinical reasoning and problem solving. Visual educational tools were introduced in a lecture that included their various types, possible benefits, and some examples. Each group made one mechanistic case diagram per week, and each student designed one diagnostic schema or therapeutic algorithm per week, based on their learning issues. The students were also told to provide commentary, which was intended to give insights into their truthfulness. Subsequently, the author administered a questionnaire about the usefulness and weakness of visual educational tools and the difficulties with performing the work. Also, the qualities of the products were assessed by the author. There were many complaints about the adequacy of the introduction of visual educational tools, also revealed by the many initial inappropriate types of products. However, the exercise presentation in the first week improved the level of understanding regarding their purposes and the method of design. In general, students agreed on the benefits of their help in providing a deep understanding of the cases and the possibility of solving clinical problems efficiently. The commentary was helpful in evaluating the truthfulness of their efforts. Students gave suggestions for increasing the percentage of their scores, considering the efforts. Using multiple types of visual educational tools during PBL can be useful in understanding the diverse routes of clinical reasoning and clinical features.
An Exploratory Multiple Case Study about Using Game-Based Learning in STEM Classrooms
ERIC Educational Resources Information Center
Vu, Phu; Feinstein, Sheryl
2017-01-01
This exploratory multiple case study attempted to examine whether game-based learning activities had any impacts on students' academic performances and behaviors, and what perceptions the teachers had toward implementing games into their classrooms. Data used in this study included 101 students' pre and post-test scores, and four structured…
Where Adults Go: A Multiple Case Study of Adult Serving Undergraduate Colleges and Universities
ERIC Educational Resources Information Center
Dixon-Williams, Shelley B.
2010-01-01
This research is an exploratory multiple case study of adult serving undergraduate colleges and universities. Using the Council of Adult and Experiential Learning (CAEL) Principles of Effective Practice for Serving Adult Learners, this study examines the differences of adult serving undergraduate colleges across the three sectors of higher…
ERIC Educational Resources Information Center
Brown, Lenis Colton
2017-01-01
The purpose of this qualitative, multiple case study was to illuminate the prevalence and configurations of peer mentoring programs at Central California Community Colleges with emphasis on how the programs impacted student retention. The study's sample was drawn from ten campuses and five centers that operate within five California Community…
Dietary Cholesterol Intake and Risk of Lung Cancer: A Meta-Analysis.
Lin, Xiaojing; Liu, Lingli; Fu, Youyun; Gao, Jing; He, Yunyun; Wu, Yang; Lian, Xuemei
2018-02-08
Multiple epidemiologic studies have evaluated the relationship between dietary cholesterol and lung cancer risk, but the association is controversial and inconclusive. A meta-analysis of case-control studies and cohort studies was conducted to evaluate the relationship between dietary cholesterol intake and lung cancer risk in this study. A relevant literature search up to October 2017 was performed in Web of Science, PubMed, China National Knowledge Infrastructure, Sinomed, and VIP Journal Integration Platform. Ten case-control studies and six cohort studies were included in the meta-analysis, and the risk estimates were pooled using either fixed or random effects models. The case-control studies with a total of 6894 lung cancer cases and 29,736 controls showed that dietary cholesterol intake was positively associated with lung cancer risk (Odds Ratio = 1.70, 95% Confidence Interval: 1.43-2.03). However, there was no evidence of an association between dietary cholesterol intake and risk of lung cancer among the 241,920 participants and 1769 lung cancer cases in the cohort studies (Relative Risk = 1.08, 95% Confidence Interval: 0.94-1.25). Due to inconsistent results from case-control and cohort studies, it is difficult to draw any conclusion regarding the effects of dietary cholesterol intake on lung cancer risk. Carefully designed and well-conducted cohort studies are needed to identify the association between dietary cholesterol and lung cancer risk.
Maternal DNA hypomethylation and congenital heart defects
Chowdhury, Shimul; Cleves, Mario A.; MacLeod, Stewart L.; James, S. Jill; Zhao, Weizhi; Hobbs, Charlotte A.
2011-01-01
Background Congenital heart defects (CHDs) are among the most prevalent and serious of birth defects. Multiple maternal factors are thought to contribute to CHD development including folate intake. Maternal DNA methylation, which is dependent on folate metabolism, may impact the risk of CHDs. Objective Our study was designed to determine whether maternal long interspersed nucleotide elements-1 (LINE-1) DNA hypomethylation is associated with increased occurrence of non-syndromic CHDs and whether maternal folate-dependent metabolites are correlated with DNA methylation status. Design Using a case-control study design, we measured global DNA methylation status among mothers whose pregnancies were affected by non-syndromic CHDs (n=180) and mothers of unaffected pregnancies (n=187). Methylation of LINE-1 was used as a surrogate marker of global DNA methylation status. The association between DNA methylation and CHD risk was determined while adjusting for selected lifestyle factors. Results LINE-1 DNA methylation was significantly lower in cases compared with controls (p=0.049). After covariate adjustments, a significant difference between cases and controls remained (p=0.010). Among women with LINE-1 methylation in the lowest decile of DNA methylation, the estimated risk of having a CHD-affected pregnancy was almost twice that of women in all other deciles (OR=1.91; 95% CI: 1.03, 3.58). Conclusions Our findings indicate that maternal LINE-1 DNA hypomethylation is associated with an increased risk of CHDs. Future studies investigating the association between maternal DNA methylation patterns and CHDs should be pursued. PMID:21254366
Ondeck, Nathaniel T; Fu, Michael C; Skrip, Laura A; McLynn, Ryan P; Cui, Jonathan J; Basques, Bryce A; Albert, Todd J; Grauer, Jonathan N
2018-04-09
The presence of missing data is a limitation of large datasets, including the National Surgical Quality Improvement Program (NSQIP). In addressing this issue, most studies use complete case analysis, which excludes cases with missing data, thus potentially introducing selection bias. Multiple imputation, a statistically rigorous approach that approximates missing data and preserves sample size, may be an improvement over complete case analysis. The present study aims to evaluate the impact of using multiple imputation in comparison with complete case analysis for assessing the associations between preoperative laboratory values and adverse outcomes following anterior cervical discectomy and fusion (ACDF) procedures. This is a retrospective review of prospectively collected data. Patients undergoing one-level ACDF were identified in NSQIP 2012-2015. Perioperative adverse outcome variables assessed included the occurrence of any adverse event, severe adverse events, and hospital readmission. Missing preoperative albumin and hematocrit values were handled using complete case analysis and multiple imputation. These preoperative laboratory levels were then tested for associations with 30-day postoperative outcomes using logistic regression. A total of 11,999 patients were included. Of this cohort, 63.5% of patients had missing preoperative albumin and 9.9% had missing preoperative hematocrit. When using complete case analysis, only 4,311 patients were studied. The removed patients were significantly younger, healthier, of a common body mass index, and male. Logistic regression analysis failed to identify either preoperative hypoalbuminemia or preoperative anemia as significantly associated with adverse outcomes. When employing multiple imputation, all 11,999 patients were included. Preoperative hypoalbuminemia was significantly associated with the occurrence of any adverse event and severe adverse events. Preoperative anemia was significantly associated with the occurrence of any adverse event, severe adverse events, and hospital readmission. Multiple imputation is a rigorous statistical procedure that is being increasingly used to address missing values in large datasets. Using this technique for ACDF avoided the loss of cases that may have affected the representativeness and power of the study and led to different results than complete case analysis. Multiple imputation should be considered for future spine studies. Copyright © 2018 Elsevier Inc. All rights reserved.
Cross-Sectional Time Series Designs: A General Transformation Approach.
ERIC Educational Resources Information Center
Velicer, Wayne F.; McDonald, Roderick P.
1991-01-01
The general transformation approach to time series analysis is extended to the analysis of multiple unit data by the development of a patterned transformation matrix. The procedure includes alternatives for special cases and requires only minor revisions in existing computer software. (SLD)
Engineering design in the primary school: applying stem concepts to build an optical instrument
NASA Astrophysics Data System (ADS)
King, Donna; English, Lyn D.
2016-12-01
Internationally there is a need for research that focuses on STEM (Science, Technology, Engineering and Mathematics) education to equip students with the skills needed for a rapidly changing future. One way to do this is through designing engineering activities that reflect real-world problems and contextualise students' learning of STEM concepts. As such, this study examined the learning that occurred when fifth-grade students completed an optical engineering activity using an iterative engineering design model. Through a qualitative methodology using a case study design, we analysed multiple data sources including students' design sketches from eight focus groups. Three key findings emerged: first, the collaborative process of the first design sketch enabled students to apply core STEM concepts to model construction; second, during the construction stage students used experimentation for the positioning of lenses, mirrors and tubes resulting in a simpler 'working' model; and third, the redesign process enabled students to apply structural changes to their design. The engineering design model was useful for structuring stages of design, construction and redesign; however, we suggest a more flexible approach for advanced applications of STEM concepts in the future.
Multiple Case Study of STEM in School-Based Agricultural Education
ERIC Educational Resources Information Center
Stubbs, Eric A.; Myers, Brian E.
2015-01-01
This multiple case study investigated the integration of science, technology, engineering, and mathematics (STEM) in three Florida high school agriculture programs. Observations, interviews, documents, and artifacts provided qualitative data that indicated the types of STEM knowledge taught. Variables of interest included student and teacher…
Multiple spinal metastases from a well-differentiated liposarcoma of the iliac wing: a case report
Ben Nsir, A; Boubaker, A; Kassar, AZ; Abderrahmen, K; Kchir, N; Jemel, H
2015-01-01
Study design: A case report. Objectives: To report an unusual case of multiple spinal metastases from an undiagnosed well-differentiated liposarcoma (WDLPS) of the iliac wing and to stress the need of a meticulous clinical examination and further screening of patients with chronic and asymptomatic bony lesions. Setting: University of medicine of Monastir, Department of neurological surgery, Fattouma Bourguiba University Hospital, Monastir, Tunisia and University of Medicine of Tunis EL Manar, Department of neurological surgery, Tunisian National Institute of Neurology, Tunis, Tunisia. Methods: A 39-year-old man presented with signs of spinal cord compression for the past 2 weeks. His medical history was consistent for an asymptomatic right iliac wing mass that appeared 3 years ago and for which he has not consulted. Magnetic resonance imaging revealed multiple bony lesions of the thoraco-lumbar spine associated with a 6-cm right paravertebral mass at the T4 level extending posteriorly through the intervertebral foramina to the spinal canal causing major spinal cord compression. An emergent T2–T6 laminectomy allowed for a complete resection of the epidural mass. Pathological examination confirmed the diagnosis of well-differentiated liposarcoma. Adjunctive radiation therapy was administered. Results: The patient’s neurological status improved remarkably under an intensive care and rehabilitation program. He was ambulatory without assistance in the second postoperative week. Conclusion: The case reported in this paper represents a genuine example of the possible metastatic potential of WDLPSs of the bone and underscores the importance of examining patients thoroughly, especially when they have chronic and asymptomatic lesions. PMID:28053711
A study of X-ray multiple diffraction by means of section topography.
Kohn, V G; Smirnova, I A
2015-09-01
The results of theoretical and experimental study are presented for the question of how the X-ray multiple diffraction in a silicon single crystal influences the interference fringes of section topography for the 400 reflection in the Laue case. Two different cases of multiple diffraction are discovered for zero and very small values of the azimuthal angle for the sample in the form of a plate with the surface normal to the 001 direction. The cases are seen on the same topogram without rotation of the crystal. Accurate computer simulations of the section topogram for the case of X-ray multiple diffraction are performed for the first time. It is shown that the structure of interference fringes on the section topogram in the region of multiple diffraction becomes more complicated. It has a very sharp dependence on the azimuthal angle. The experiment is carried out using a laboratory source under conditions of low resolution over the azimuthal angle. Nevertheless, the characteristic inclination of the interference fringes on the tails of the multiple diffraction region is easily seen. This phenomenon corresponds completely to the computer simulations.
Hershman, Stuart H.; Kunkle, William A.; Kelly, Michael P.; Buchowski, Jacob M.; Ray, Wilson Z.; Bumpass, David B.; Gum, Jeffrey L.; Peters, Colleen M.; Singhatanadgige, Weerasak; Kim, Jin Young; Smith, Zachary A.; Hsu, Wellington K.; Nassr, Ahmad; Currier, Bradford L.; Rahman, Ra’Kerry K.; Isaacs, Robert E.; Smith, Justin S.; Shaffrey, Christopher; Thompson, Sara E.; Wang, Jeffrey C.; Lord, Elizabeth L.; Buser, Zorica; Arnold, Paul M.; Fehlings, Michael G.; Mroz, Thomas E.
2017-01-01
Study Design: Multicenter retrospective case series and review of the literature. Objective: To determine the rate of esophageal perforations following anterior cervical spine surgery. Methods: As part of an AOSpine series on rare complications, a retrospective cohort study was conducted among 21 high-volume surgical centers to identify esophageal perforations following anterior cervical spine surgery. Staff at each center abstracted data from patients’ charts and created case report forms for each event identified. Case report forms were then sent to the AOSpine North America Clinical Research Network Methodological Core for data processing and analysis. Results: The records of 9591 patients who underwent anterior cervical spine surgery were reviewed. Two (0.02%) were found to have esophageal perforations following anterior cervical spine surgery. Both cases were detected and treated in the acute postoperative period. One patient was successfully treated with primary repair and debridement. One patient underwent multiple debridement attempts and expired. Conclusions: Esophageal perforation following anterior cervical spine surgery is a relatively rare occurrence. Prompt recognition and treatment of these injuries is critical to minimizing morbidity and mortality. PMID:28451488
The case-control design in veterinary sciences: A survey.
Cullen, Jonah N; Sargeant, Jan M; Makielski, Kelly M; O'Connor, Annette M
2016-11-01
The case-control study design is deceptively simple. However, many design considerations influence the estimated effect measure. An investigation of case-control studies in the human health literature suggested that some of these considerations are not described in reports of case-control studies. Our hypothesis was that the majority of veterinary studies labeled as case-controls would be incident density designs, and many would not interpret the effect measure obtained from those studies as the rate ratio rather than the odds ratio. Reference databases were searched for author-designated case-control studies. A survey of 100 randomly selected studies was conducted to examine the different design options described and estimated effect measures. Of the 100 author-identified case-control studies, 83 assessed an exposure-outcome association and, of those, only 54 (65.1%) sampled the study population based on an outcome and would thus be considered case-control designs. Twelve studies were incidence density designs but none used this terminology. Of the studies that reported an odds ratio as the effect measure, none reported on additional considerations that would have enabled a more interpretable result. This survey indicated many case-control-labeled studies were not case-control designs and among case-control studies, key design aspects were not often described. The absence of information about study design elements and underlying assumptions in case-control studies limits the ability to establish the effect measured by the study and the evidentiary value of the study might be underestimated. Copyright © 2016 Elsevier B.V. All rights reserved.
Siek, Katie A; Khan, Danish U; Ross, Stephen E; Haverhals, Leah M; Meyers, Jane; Cali, Steven R
2011-10-01
Older adults with multiple chronic conditions often go through care transitions where they move between care facilities or providers during their treatment. These transitions are often uncoordinated and can imperil patients by omitted, duplicative, or contradictory care plans. Older adults sometimes feel overwhelmed with the new responsibility of coordinating the care plan with providers and changing their medication regimes. In response, we developed a Lesser General Public License (LGPL) open source, web-based Personal Health Application (PHA) using an iterative participatory design process that provided older adults and their caregivers the ability to manage their personal health information. In this paper, we document the PHA design process from low-fidelity prototypes to high-fidelity prototypes over the course of six user studies. Our findings establish the imperative need for interdisciplinary research and collaboration among all stakeholders to create effective PHAs. We conclude with design guidelines that encourage researchers to gradually increase functionality as users become more proficient.
Principles and tools for collaborative entity-based intelligence analysis.
Bier, Eric A; Card, Stuart K; Bodnar, John W
2010-01-01
Software tools that make it easier for analysts to collaborate as a natural part of their work will lead to better analysis that is informed by more perspectives. We are interested to know if software tools can be designed that support collaboration even as they allow analysts to find documents and organize information (including evidence, schemas, and hypotheses). We have modified the Entity Workspace system, described previously, to test such designs. We have evaluated the resulting design in both a laboratory study and a study where it is situated with an analysis team. In both cases, effects on collaboration appear to be positive. Key aspects of the design include an evidence notebook optimized for organizing entities (rather than text characters), information structures that can be collapsed and expanded, visualization of evidence that emphasizes events and documents (rather than emphasizing the entity graph), and a notification system that finds entities of mutual interest to multiple analysts. Long-term tests suggest that this approach can support both top-down and bottom-up styles of analysis.
ERIC Educational Resources Information Center
Lo, Ya-yu; Starling, A. Leyf Peirce
2009-01-01
This study examined the effects of a graphing task analysis using the Microsoft[R] Office Excel 2007 program on the single-subject multiple baseline graphing skills of three university graduate students. Using a multiple probe across participants design, the study demonstrated a functional relationship between the number of correct graphing…
Omar, R Z; Morton, L S; Beirne, M; Blot, W J; Lawford, P V; Hose, R; Taylor, K M
2001-06-01
Björk-Shiley 60 degrees convexo-concave prosthetic heart valves (Shiley, Inc, Irvine, Calif, a subsidiary of Pfizer, Inc) continue to be a concern for approximately 35,000 nonexplanted patients worldwide, with approximately 600 events reported to the manufacturer to date. Fractures of the outlet struts of the valves began to appear in the early 1980s and have continued to the present, but their causes are only partially understood. A matched case-control study was conducted evaluating manufacturing records for 52 valves with outlet strut fractures and 248 control subjects matched for age at implantation, valve size, and valve position. In addition to the risk factors recognized as determinants of outlet strut fracture, the United Kingdom case-control study has observed 7- to 9-fold increased risk with performance of multiple hook deflection tests. This test was performed more than once, usually after rework on the valve. Six valves in this study underwent multiple hook deflection tests, of which 4 experienced an outlet strut fracture. Cracks and further rework were noted for these valves. Significant associations were also observed between outlet strut fracture and disc-to-strut gap measurements taken before the attachment of the sewing ring. It is our view that a combination of factors related to valve design, manufacturing process, and patient characteristics are responsible for outlet strut fractures of Björk-Shiley convexo-concave valves. Multiple hook deflection tests have emerged as a potential new risk factor for outlet strut fracture in both The Netherlands and the United Kingdom. This factor appears to be correlated with the presence of other abnormalities. A further study is needed to investigate the factors correlated with multiple hook deflection tests. On confirmation of risk, the presence of multiple hook deflection tests may be added to equations, quantifying the risk of outlet strut fracture for comparison against risk of mortality and serious morbidity from explant operations.
Postapproval Development Options in COPD: A Case Study in Value-Based Healthcare Systems.
Murphy, Michael F; Antonini, Paola; Lai, Zhihong Vicki
2011-01-01
Research and development activities in an era of globalization encounter a mosaic of providers, products, services, and intermediaries; regulatory and other government institutions; and consumers. The introduction of novel therapeutics into this environment mandates research programs that are relevant to the registration process, payers and purchasers, transparent pricing, and rule-driven business practices, while providing data relevant to marketing initiatives internationally. To outline an example for clinical development programs that incorporate the perspective of multiple stakeholders into a portfolio of study designs to provide optimal data platforms that can resonate with diverse recipients. A contract research organization directly involved in the design, execution, and analysis of clinical trials for new drugs and devices across pharmaceutical and biotechnology companies provides a unique perspective regarding opportunities and challenges within the international clinical research environment. Drs Murphy, Antonini, and Lai, representing Worldwide Clinical Trials, utilize chronic obstructive pulmonary disease as a demonstration project exploiting its prevalence, direct and indirect costs, and the rapid infusion/diffusion of innovative therapy into practice as a rationale for focus, and illustrate methods of informing registration and technology assessments during a prototypical development process. By virtue of its chronicity, prevalence, and pattern of healthcare utilization, chronic obstructive pulmonary disease provides an ideal case for illustrating the application of clinical trial methodology that can facilitate data evaluation through the prism of multiple stakeholders. Adding an international dimension exacerbates system complexity and serves to illustrate the breadth of issues that can be addressed within this therapeutic area.
Bartholomew, Theodore T; Lockard, Allison J
2018-06-13
Mixed methods can foster depth and breadth in psychological research. However, its use remains in development in psychotherapy research. Our purpose was to review the use of mixed methods in psychotherapy research. Thirty-one studies were identified via the PRISMA systematic review method. Using Creswell & Plano Clark's typologies to identify design characteristics, we assessed each study for rigor and how each used mixed methods. Key features of mixed methods designs and these common patterns were identified: (a) integration of clients' perceptions via mixing; (b) understanding group psychotherapy; (c) integrating methods with cases and small samples; (d) analyzing clinical data as qualitative data; and (e) exploring cultural identities in psychotherapy through mixed methods. The review is discussed with respect to the value of integrating multiple data in single studies to enhance psychotherapy research. © 2018 Wiley Periodicals, Inc.
Effects of peer-mediated implementation of visual scripts in middle school.
Ganz, Jennifer B; Heath, Amy K; Lund, Emily M; Camargo, Siglia P H; Rispoli, Mandy J; Boles, Margot; Plaisance, Lauren
2012-05-01
Although research has investigated the impact of peer-mediated interventions and visual scripts on social and communication skills in children with autism spectrum disorders, no studies to date have investigated peer-mediated implementation of scripts. This study investigated the effects of peer-implemented scripts on a middle school student with autism, intellectual impairments, and speech-language impairment via a multiple baseline single-case research design across behaviors. The target student demonstrated improvements in three communicative behaviors when implemented by a trained peer; however, behaviors did not generalize to use with an untrained typically developing peer.
Healthcare managers' decision making: findings of a small scale exploratory study.
Macdonald, Jackie; Bath, Peter A; Booth, Andrew
2008-12-01
Managers who work in publicly funded healthcare organizations are an understudied group. Some of the influences on their decisions may be unique to healthcare. This study considers how to integrate research knowledge effectively into healthcare managers' decision making, and how to manage and integrate information that will include community data. This first phase in a two-phase mixed methods research study used a qualitative, multiple case studies design. Nineteen semi-structured interviews were undertaken using the critical incident technique. Interview transcripts were analysed using the NatCen Framework. One theme represented ;information and decisions'. Cases were determined to involve complex multi-level, multi-situational decisions with participants in practical rather than ceremonial work roles. Most considered organizational knowledge in the first two decision phases and external knowledge, including research, in the third phase. All participants engaged in satisficing to some degree.
Bayard, David S.; Neely, Michael
2016-01-01
An experimental design approach is presented for individualized therapy in the special case where the prior information is specified by a nonparametric (NP) population model. Here, a nonparametric model refers to a discrete probability model characterized by a finite set of support points and their associated weights. An important question arises as to how to best design experiments for this type of model. Many experimental design methods are based on Fisher Information or other approaches originally developed for parametric models. While such approaches have been used with some success across various applications, it is interesting to note that they largely fail to address the fundamentally discrete nature of the nonparametric model. Specifically, the problem of identifying an individual from a nonparametric prior is more naturally treated as a problem of classification, i.e., to find a support point that best matches the patient’s behavior. This paper studies the discrete nature of the NP experiment design problem from a classification point of view. Several new insights are provided including the use of Bayes Risk as an information measure, and new alternative methods for experiment design. One particular method, denoted as MMopt (Multiple-Model Optimal), will be examined in detail and shown to require minimal computation while having distinct advantages compared to existing approaches. Several simulated examples, including a case study involving oral voriconazole in children, are given to demonstrate the usefulness of MMopt in pharmacokinetics applications. PMID:27909942
Bayard, David S; Neely, Michael
2017-04-01
An experimental design approach is presented for individualized therapy in the special case where the prior information is specified by a nonparametric (NP) population model. Here, a NP model refers to a discrete probability model characterized by a finite set of support points and their associated weights. An important question arises as to how to best design experiments for this type of model. Many experimental design methods are based on Fisher information or other approaches originally developed for parametric models. While such approaches have been used with some success across various applications, it is interesting to note that they largely fail to address the fundamentally discrete nature of the NP model. Specifically, the problem of identifying an individual from a NP prior is more naturally treated as a problem of classification, i.e., to find a support point that best matches the patient's behavior. This paper studies the discrete nature of the NP experiment design problem from a classification point of view. Several new insights are provided including the use of Bayes Risk as an information measure, and new alternative methods for experiment design. One particular method, denoted as MMopt (multiple-model optimal), will be examined in detail and shown to require minimal computation while having distinct advantages compared to existing approaches. Several simulated examples, including a case study involving oral voriconazole in children, are given to demonstrate the usefulness of MMopt in pharmacokinetics applications.
Childhood Giftedness, Adolescent Agency: A Systemic Multiple-Case Study
ERIC Educational Resources Information Center
Mudrak, Jiri; Zabrodska, Katerina
2015-01-01
Although considerable research has addressed development from childhood giftedness to adult excellence, subjective perceptions of this development by gifted individuals themselves have remained largely unexplored. This multiple case study examined the ways in which young adults, who in the past had been identified as gifted, made sense of their…
Hierarchical Modeling and Robust Synthesis for the Preliminary Design of Large Scale Complex Systems
NASA Technical Reports Server (NTRS)
Koch, Patrick N.
1997-01-01
Large-scale complex systems are characterized by multiple interacting subsystems and the analysis of multiple disciplines. The design and development of such systems inevitably requires the resolution of multiple conflicting objectives. The size of complex systems, however, prohibits the development of comprehensive system models, and thus these systems must be partitioned into their constituent parts. Because simultaneous solution of individual subsystem models is often not manageable iteration is inevitable and often excessive. In this dissertation these issues are addressed through the development of a method for hierarchical robust preliminary design exploration to facilitate concurrent system and subsystem design exploration, for the concurrent generation of robust system and subsystem specifications for the preliminary design of multi-level, multi-objective, large-scale complex systems. This method is developed through the integration and expansion of current design techniques: Hierarchical partitioning and modeling techniques for partitioning large-scale complex systems into more tractable parts, and allowing integration of subproblems for system synthesis; Statistical experimentation and approximation techniques for increasing both the efficiency and the comprehensiveness of preliminary design exploration; and Noise modeling techniques for implementing robust preliminary design when approximate models are employed. Hierarchical partitioning and modeling techniques including intermediate responses, linking variables, and compatibility constraints are incorporated within a hierarchical compromise decision support problem formulation for synthesizing subproblem solutions for a partitioned system. Experimentation and approximation techniques are employed for concurrent investigations and modeling of partitioned subproblems. A modified composite experiment is introduced for fitting better predictive models across the ranges of the factors, and an approach for constructing partitioned response surfaces is developed to reduce the computational expense of experimentation for fitting models in a large number of factors. Noise modeling techniques are compared and recommendations are offered for the implementation of robust design when approximate models are sought. These techniques, approaches, and recommendations are incorporated within the method developed for hierarchical robust preliminary design exploration. This method as well as the associated approaches are illustrated through their application to the preliminary design of a commercial turbofan turbine propulsion system. The case study is developed in collaboration with Allison Engine Company, Rolls Royce Aerospace, and is based on the Allison AE3007 existing engine designed for midsize commercial, regional business jets. For this case study, the turbofan system-level problem is partitioned into engine cycle design and configuration design and a compressor modules integrated for more detailed subsystem-level design exploration, improving system evaluation. The fan and low pressure turbine subsystems are also modeled, but in less detail. Given the defined partitioning, these subproblems are investigated independently and concurrently, and response surface models are constructed to approximate the responses of each. These response models are then incorporated within a commercial turbofan hierarchical compromise decision support problem formulation. Five design scenarios are investigated, and robust solutions are identified. The method and solutions identified are verified by comparison with the AE3007 engine. The solutions obtained are similar to the AE3007 cycle and configuration, but are better with respect to many of the requirements.
Özkan Tuncay, Fatma; Mollaoğlu, Mukadder
2017-12-01
To determine the effects of cooling suit on fatigue and activities of daily living of individuals with multiple sclerosis. Fatigue is one of the most common symptoms in people with multiple sclerosis and adversely affects their activities of daily living. Studies evaluating fatigue associated with multiple sclerosis have reported that most of the fatigue cases are related to the increase in body temperature and that cooling therapy is effective in coping with fatigue. This study used a two sample, control group design. The study sample comprised 75 individuals who met the inclusion criteria. Data were collected with study forms. After the study data were collected, cooling suit treatment was administered to the experimental group. During home visits paid at the fourth and eighth weeks after the intervention, the aforementioned scales were re-administered to the participants in the experimental and control groups. The analyses performed demonstrated that the severity levels of fatigue experienced by the participants in the experimental group wearing cooling suit decreased. The experimental group also exhibited a significant improvement in the participants' levels of independence in activities of daily living. The cooling suit worn by individuals with multiple sclerosis was determined to significantly improve the participants' levels of fatigue and independence in activities of daily living. The cooling suit therapy was found to be an effective intervention for the debilitating fatigue suffered by many multiple sclerosis patients, thus significantly improving their level of independence in activities of daily living. © 2017 John Wiley & Sons Ltd.
Nyamathi, Adeline M.; Zhang, Sheldon; Wall, Sarah; Hall, Elizabeth A.; Salem, Benissa E.; Farabee, David; Faucette, Mark; Yadav, Kartik
2016-01-01
Background Transitioning into society after release from incarceration presents real challenges for male offenders; in California, up to 60% return to prison within three years following release. The risk for ongoing drug use and having sex with multiple sex partners is a significant challenge for ex-offenders preparing to enter the community. Objectives The aims are to describe drug use and sexual behavior (sex with multiple partners) prior to incarceration and six and 12 months following study enrollment using data obtained as part of a randomized controlled trial (RCT). Methods This is a planned secondary analysis of data obtained as part of an RCT designed to study the effects of intensive peer coaching and nurse case management, intensive peer coaching, and brief nurse counseling on hepatitis A and B vaccination adherence compared to a usual care control treatment that also included brief peer coaching and brief nurse counseling. Self-report data from subjects enrolled at one residential drug treatment facility in Los Angeles were captured at three time points: baseline, and six- and 12-month follow up. Results Findings showed substantive and significant reductions in drug use and engaging in sex with multiple partners six months following enrollment into the study compared to the baseline data, but results did not differ by study condition. At 12-month follow up, drug use and sex with multiple partners increased, but remained less than at baseline levels. Discussion Sustaining reductions in drug use and engaging in sex with multiple partners remains a challenge following incarceration. PMID:27124254
Das, Sushant K; Zeng, Li-Chuan; Li, Bing; Niu, Xiang-Ke; Wang, Jing-Liang; Bhetuwal, Anup; Yang, Han-Feng
2014-09-28
Occasionally systemic complications with high risk of death, such as multiple organ dysfunction syndrome (MODS), can occur following multiple bee stings. This case study reports a patient who presented with MODS, i.e., acute kidney injury, hepatic and cardiac dysfunction, after multiple bee stings. The standard clinical findings were then correlated with magnetic resonance imaging (MRI) findings, which demonstrates that MRI may be utilized as a simpler tool to use than other multiple diagnostics.
Conservatism implications of shock test tailoring for multiple design environments
NASA Technical Reports Server (NTRS)
Baca, Thomas J.; Bell, R. Glenn; Robbins, Susan A.
1987-01-01
A method for analyzing shock conservation in test specifications that have been tailored to qualify a structure for multiple design environments is discussed. Shock test conservation is qualified for shock response spectra, shock intensity spectra and ranked peak acceleration data in terms of an Index of Conservation (IOC) and an Overtest Factor (OTF). The multi-environment conservation analysis addresses the issue of both absolute and average conservation. The method is demonstrated in a case where four laboratory tests have been specified to qualify a component which must survive seven different field environments. Final judgment of the tailored test specification is shown to require an understanding of the predominant failure modes of the test item.
Roy, Sandip; McElwain, Terry F; Wan, Yan
2011-10-01
Developing control policies for zoonotic diseases is challenging, both because of the complex spread dynamics exhibited by these diseases, and because of the need for implementing complex multi-species surveillance and control efforts using limited resources. Mathematical models, and in particular network models, of disease spread are promising as tools for control-policy design, because they can provide comprehensive quantitative representations of disease transmission. A layered dynamical network model for the transmission and control of zoonotic diseases is introduced as a tool for analyzing disease spread and designing cost-effective surveillance and control. The model development is achieved using brucellosis transmission among wildlife, cattle herds, and human sub-populations in an agricultural system as a case study. Precisely, a model that tracks infection counts in interacting animal herds of multiple species (e.g., cattle herds and groups of wildlife for brucellosis) and in human subpopulations is introduced. The model is then abstracted to a form that permits comprehensive targeted design of multiple control capabilities as well as model identification from data. Next, techniques are developed for such quantitative design of control policies (that are directed to both the animal and human populations), and for model identification from snapshot and time-course data, by drawing on recent results in the network control community. The modeling approach is shown to provide quantitative insight into comprehensive control policies for zoonotic diseases, and in turn to permit policy design for mitigation of these diseases. For the brucellosis-transmission example in particular, numerous insights are obtained regarding the optimal distribution of resources among available control capabilities (e.g., vaccination, surveillance and culling, pasteurization of milk) and points in the spread network (e.g., transhumance vs. sedentary herds). In addition, a preliminary identification of the network model for brucellosis is achieved using historical data, and the robustness of the obtained model is demonstrated. As a whole, our results indicate that network modeling can aid in designing control policies for zoonotic diseases.
Roy, Sandip; McElwain, Terry F.; Wan, Yan
2011-01-01
Background Developing control policies for zoonotic diseases is challenging, both because of the complex spread dynamics exhibited by these diseases, and because of the need for implementing complex multi-species surveillance and control efforts using limited resources. Mathematical models, and in particular network models, of disease spread are promising as tools for control-policy design, because they can provide comprehensive quantitative representations of disease transmission. Methodology/Principal Findings A layered dynamical network model for the transmission and control of zoonotic diseases is introduced as a tool for analyzing disease spread and designing cost-effective surveillance and control. The model development is achieved using brucellosis transmission among wildlife, cattle herds, and human sub-populations in an agricultural system as a case study. Precisely, a model that tracks infection counts in interacting animal herds of multiple species (e.g., cattle herds and groups of wildlife for brucellosis) and in human subpopulations is introduced. The model is then abstracted to a form that permits comprehensive targeted design of multiple control capabilities as well as model identification from data. Next, techniques are developed for such quantitative design of control policies (that are directed to both the animal and human populations), and for model identification from snapshot and time-course data, by drawing on recent results in the network control community. Conclusions/Significance The modeling approach is shown to provide quantitative insight into comprehensive control policies for zoonotic diseases, and in turn to permit policy design for mitigation of these diseases. For the brucellosis-transmission example in particular, numerous insights are obtained regarding the optimal distribution of resources among available control capabilities (e.g., vaccination, surveillance and culling, pasteurization of milk) and points in the spread network (e.g., transhumance vs. sedentary herds). In addition, a preliminary identification of the network model for brucellosis is achieved using historical data, and the robustness of the obtained model is demonstrated. As a whole, our results indicate that network modeling can aid in designing control policies for zoonotic diseases. PMID:22022621
A Multiple Case Study of a Baldrige-Based Peer Review Process in an Urban School District
ERIC Educational Resources Information Center
Ray, Janet L.
2012-01-01
Distinct purposes were identified for this phenomenological multiple-case study. The first purpose of the study was to determine in what ways the BbPRP influenced (a) leadership, (b) strategic planning, and (c) process management among the five selected schools within AISD. The second purpose of this study was to examine administrators'…
Yu, Yao; Hu, Hao; Bohlender, Ryan J; Hu, Fulan; Chen, Jiun-Sheng; Holt, Carson; Fowler, Jerry; Guthery, Stephen L; Scheet, Paul; Hildebrandt, Michelle A T; Yandell, Mark; Huff, Chad D
2018-04-06
High-throughput sequencing data are increasingly being made available to the research community for secondary analyses, providing new opportunities for large-scale association studies. However, heterogeneity in target capture and sequencing technologies often introduce strong technological stratification biases that overwhelm subtle signals of association in studies of complex traits. Here, we introduce the Cross-Platform Association Toolkit, XPAT, which provides a suite of tools designed to support and conduct large-scale association studies with heterogeneous sequencing datasets. XPAT includes tools to support cross-platform aware variant calling, quality control filtering, gene-based association testing and rare variant effect size estimation. To evaluate the performance of XPAT, we conducted case-control association studies for three diseases, including 783 breast cancer cases, 272 ovarian cancer cases, 205 Crohn disease cases and 3507 shared controls (including 1722 females) using sequencing data from multiple sources. XPAT greatly reduced Type I error inflation in the case-control analyses, while replicating many previously identified disease-gene associations. We also show that association tests conducted with XPAT using cross-platform data have comparable performance to tests using matched platform data. XPAT enables new association studies that combine existing sequencing datasets to identify genetic loci associated with common diseases and other complex traits.
Design of multiple-ply laminated composite tapered beams
NASA Technical Reports Server (NTRS)
Rodriguez, P.
1993-01-01
A study of a special case of symmetric laminated composite cantilever beams is presented. The approach models beams that are tapered both in depth and width and investigates the effect of the ply layup angle and the ply taper on bending and interlaminar shearing stresses. For the determination of stresses and deflections, the beam stiffness matrices are expressed as linear functions of the beam length. Using classical lamination theory (CLT) the stiffness matrices are determined and assembled at strategic locations along the length of the beam. They are then inverted and necessary stiffness parameters are obtained numerically and extracted for determination of design information at each location chosen. Several ply layup configurations are investigated, and design considerations are presented based on the findings. Finally, recommendations for the design of these beams are presented, and a means for anticipating the location of highest stresses is offered.
Design of multiple-ply laminated composite tapered beams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rodriguez, P.
1993-06-01
A study of a special case of symmetric laminated composite cantilever beams is presented. The approach models beams that are tapered both in depth and width and investigates the effect of the ply layup angle and the ply taper on bending and interlaminar shearing stresses. For the determination of stresses and deflections, the beam stiffness matrices are expressed as linear functions of the beam length. Using classical lamination theory (CLT) the stiffness matrices are determined and assembled at strategic locations along the length of the beam. They are then inverted and necessary stiffness parameters are obtained numerically and extracted formore » determination of design information at each location chosen. Several ply layup configurations are investigated, and design considerations are preSDsented based on the findings. Finally, recommendations for the design of these beams are presented, and a means for anticipating the location of highest stresses is offered.« less
Case Study: Puttin' on the Ritz: How to Put Science into Cases
ERIC Educational Resources Information Center
Herreid, Clyde Freeman
2017-01-01
There are multiple ways to put science into a case. This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses different ways of presenting science in case studies.
75 FR 48349 - Agency Forms Undergoing Paperwork Reduction Act review
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-10
... monitor syndrome-based (e.g., case information collected in emergency departments (EDs) and diagnostic... syndromic surveillance systems. EARS has been designed and used to monitor syndromic data from emergency... events such as the Beijing Summer Olympics; multiple Superbowls (football) and World Series (baseball...
NASA Astrophysics Data System (ADS)
Prince, Joan Marie
1999-12-01
Over the past years, progress in Black academic achievement, particularly in the area of science, has generally slowed or ceased. According to the 1994 NAEP assessment, twelfth-grade Black students are performing at the level of White eighth-grade students in the discipline of science (Department of Education, 1996). These students, in their last year of required schooling, are about to graduate, yet they lag at least four years behind their white counterparts in science achievement. Despite the establishment and implementation of numerous science intervention programs, Black students still suffer from a disparate gap in standardized test score achievement. The purpose of this research is to investigate teachers' perceptions of the effectiveness of an urban sciences intervention tool that was designed to assist in narrowing the Black-White science academic achievement gap. Specifically, what factors affect teachers' personal sense of instructional efficacy, and how does this translate into their outcome expectancy for student academic success? A multiple-case, replicative design, grounded in descriptive theory, was selected for the study. Multiple sources of evidence were queried to provide robust findings. These sources included a validated health sciences self-efficacy instrument, an interview protocol, a classroom observation, and a review of archival material that included case study participants' personnel files and meeting minutes. A cross-comparative analytic approach was selected for interpretation (Yin, 1994). Findings indicate that teachers attribute the success or failure of educational intervention tools in closing the Black-White test score gap to a variety of internal and external factors. These factors included a perceived lack of both monetary and personal support by the school leadership, as well as a perceived lack of parental involvement which impacted negatively on student achievement patterns. The case study participants displayed a depressed outcome expectancy effect for successful student achievement, which they directly attributed to the barriers stated above. If educational reforms are to be successful, the issues of teachers' perceptions of factors that inhibit their personal ability to instruct, and how that translates to student academic achievement must be addressed.
ERIC Educational Resources Information Center
Minger, Leslie
2017-01-01
The purpose of this multiple case study was to explore and describe the leadership communication practices of school principals in Southern California schools with demonstrated high levels of academic performance in order to identify practices that might be replicated in other schools. Communication practices were studied in relation to two…
Multiple Case Study on Cyberbullying's Impacts on Adolescent Technology Use
ERIC Educational Resources Information Center
Thompson, Kent W.
2013-01-01
This multiple case study focused on whether and how cyberbullying had an impact on students' use of technology. Analysis of the lived experiences of the participants in this study added depth to the quantitative research previously conducted by others in this area. The conceptual framework was based on social learning theory, which suggested that…
The MORPG-Based Learning System for Multiple Courses: A Case Study on Computer Science Curriculum
ERIC Educational Resources Information Center
Liu, Kuo-Yu
2015-01-01
This study aimed at developing a Multiplayer Online Role Playing Game-based (MORPG) Learning system which enabled instructors to construct a game scenario and manage sharable and reusable learning content for multiple courses. It used the curriculum of "Introduction to Computer Science" as a study case to assess students' learning…
Variable structure control of spacecraft reorientation maneuvers
NASA Technical Reports Server (NTRS)
Sira-Ramirez, H.; Dwyer, T. A. W., III
1986-01-01
A Variable Structure Control (VSC) approach is presented for multi-axial spacecraft reorientation maneuvers. A nonlinear sliding surface is proposed which results in an asymptotically stable, ideal linear sliding motion of Cayley-Rodriques attitude parameters. By imposing a desired equivalent dynamics on the attitude parameters, the approach is devoid of optimal control considerations. The single axis case provides a design scheme for the multiple axes design problem. Illustrative examples are presented.
2012-01-01
Background A number of single case reports have suggested that the context within which intervention studies take place may challenge the assumptions that underpin randomised controlled trials (RCTs). However, the diverse ways in which context may challenge the central tenets of the RCT, and the degree to which this information is known to researchers or subsequently reported, has received much less attention. In this paper, we explore these issues by focusing on seven RCTs of interventions varying in type and degree of complexity, and across diverse contexts. Methods This in-depth multiple case study using interviews, focus groups and documentary analysis was conducted in two phases. In phase one, a RCT of a nurse-led intervention provided a single exploratory case and informed the design, sampling and data collection within the main study. Phase two consisted of a multiple explanatory case study covering a spectrum of trials of different types of complex intervention. A total of eighty-four data sources across the seven trials were accessed. Results We present consistent empirical evidence across all trials to indicate that four key elements of context (personal, organisational, trial and problem context) are crucial to understanding how a complex intervention works and to enable both assessments of internal validity and likely generalisability to other settings. The ways in which context challenged trial operation was often complex, idiosyncratic, and subtle; often falling outside of current trial reporting formats. However, information on such issues appeared to be available via first hand ‘insider accounts’ of each trial suggesting that improved reporting on the role of context is possible. Conclusions Sufficient detail about context needs to be understood and reported in RCTs of complex interventions, in order for the transferability of complex interventions to be assessed. Improved reporting formats that require and encourage the clarification of both general and project-specific threats to the likely internal and external validity need to be developed. In addition, a cultural change is required in which the open and honest reporting of such issues is seen as an indicator of study strength and researcher integrity, rather than a symbol of a poor quality study or investigator ability. PMID:22742939
Moore, Spencer; Shiell, Alan; Haines, Valerie; Riley, Therese; Collier, Carrie
2005-01-01
Background This article discusses the study design and methods used to contextualize and assess the social capital of seniors living in congregate housing residences in Calgary, Alberta. The project is being funded as a pilot project under the Institute of Aging, Canadian Institutes for Health Research. Design/Methods Working with seniors living in 5 congregate housing residencies in Calgary, the project uses a mixed method approach to develop grounded measures of the social capital of seniors. The project integrates both qualitative and quantitative methods in a 3-phase research design: 1) qualitative, 2) quantitative, and 3) qualitative. Phase 1 uses gender-specific focus groups; phase 2 involves the administration of individual surveys that include a social network module; and phase 3 uses anamolous-case interviews. Not only does the study design allow us to develop grounded measures of social capital but it also permits us to test how well the three methods work separately, and how well they fit together to achieve project goals. This article describes the selection of the study population, the multiple methods used in the research and a brief discussion of our conceptualization and measurement of social capital. PMID:15836784
Motion laws synthesis for cam mechanisms with multiple follower displacement
NASA Astrophysics Data System (ADS)
Podgornyj, Yu I.; Skeeba, V. Yu; Kirillov, A. V.; Martynova, T. G.; Skeeba, P. Yu
2018-03-01
The research discusses the cam mechanisms design. The analysis of specialized literature indicates that the synthesis of the cam mechanisms laws of motion is currently done mainly by a standard set of acceleration curves. In some cases, the designer needs to synthesize a new acceleration law which should be task-specific and enforce a certain production step. The values of the technological loads and inertia forces loads generated by the mechanism are calculated to analyze the slay mechanism behavior in the production of closely woven fabrics. Mathematical packages MathCad and SolidWorks are used in calculations. As a result of the research, the authors propose the methodology for synthesizing the slay mechanism with multiple follower displacements for the point of contact between the reed and the fabric edge. Theoretical studies have been tested on a specific machine model (STB loom). The authors have synthesized the motion law of the filling threads beat-up mechanism for the production of strong fabrics. New basic and closing cam profiles are proposed. The results are designed to enhance the possibilities of the looms and to recommend the most efficient equipment operation modes for the producers.
[The case-case-time-control study design].
Wang, Jing; Zhuo, Lin; Zhan, Siyan
2014-12-01
Although the 'self-matched case-only studies' (such as the case-cross-over or self-controlled case-series method) can control the time-invariant confounders (measured or unmeasured) through design of the study, however, they can not control those confounders that vary with time. A bidirectional case-crossover design can be used to adjust the exposure-time trends. In the areas of pharmaco-epidemiology, illness often influence the future use of medications, making a bidirectional study design problematic. Suissa's case-time-control design combines the case-crossover and the case-control design which could adjust for exposure-trend bias, but the control group may reintroduce selection bias, if the matching does not go well. We propose a "case-case-time-control" design which is an extension of the case-time-control design. However, rather than using a sample of external controls, we choose those future cases as controls for current cases to counter the bias that arising from temporal trends caused by exposure to the target of interest. In the end of this article we will discuss the strength and limitations of this design based on an applied example.
Stringer, Barbara; van Meijel, Berno; Karman, Pieter; Koekkoek, Bauke; Hoogendoorn, Adriaan W; Kerkhof, Ad J F M; Beekman, Aartjan T F
2015-07-01
To test if a collaborative care program (CCP) with nurses in a coordinating position is beneficial for patients with severe personality disorders. A pilot study with a comparative multiple case study design using mixed methods investigating active ingredients and preliminary results. Most patients, their informal caregivers, and nurses value (parts of) the CCP positively; preliminary results show a significant decrease in severity of borderline symptoms. With the CCP, we may expand the supply of available treatments for patients with (severe) personality disorders, but a larger randomized controlled trial is warranted to confirm our preliminary results. © 2014 Wiley Periodicals, Inc.
Automated Big Data Analysis in Bottom-up and Targeted Proteomics
van der Plas-Duivesteijn, Suzanne; Domański, Dominik; Smith, Derek; Borchers, Christoph; Palmblad, Magnus; Mohamme, Yassene
2014-01-01
Similar to other data intensive sciences, analyzing mass spectrometry-based proteomics data involves multiple steps and diverse software using different algorithms and data formats and sizes. Besides that the distributed and evolving nature of the data in online repositories, another challenge is that a scientists have to deal with many steps of analysis pipelines. A documented data processing is also becoming an essential part for the overall reproducibility of the results. Thanks to different e-Science initiatives, scientific workflow engines have become a means for automated, sharable and reproducible data processing. While these are designed as general tools, they can be employed to solve different challenges that we are facing in handling our Big Data. Here we present three use cases: improving the performance of different spectral search engines by decomposing input data and recomposing the resulting files, building spectral libraries from more than 20 million spectra, and integrating information from multiple resources to select most appropriate peptides for targeted proteomics analyses. The three use cases demonstrate different challenges in exploiting proteomics data analysis. In the first we integrate local and cloud processing resources in order to obtain better performance resulting in more than 30-fold speed improvement. By considering search engines as legacy software our solution is applicable to multiple search algorithms. The second use case is an example of automated processing of many data files of different sizes and locations, starting with raw data and ending with the final, ready-to-use library. This demonstrates the robustness and fault tolerance when dealing with huge amount data stored in multiple files. The third use case demonstrates retrieval and integration of information and data from multiple online repositories. In addition to the diversity of data formats and Web interfaces, this use case also illustrates how to deal with incomplete data.
Evaluation of Novel Liner Concepts for Fan and Airframe Noise Reduction
NASA Technical Reports Server (NTRS)
Jones, M. G.; Howerton, B. M.
2016-01-01
This paper presents a review of four novel liner concepts: soft vanes, over-the-rotor liners, external liners, and flap side-edge liners. A number of similarities in the design and evaluation of these concepts emerged during these investigations. Since these were the first attempts to study these particular liner concepts, there was limited information to guide the design process. In all cases, the target frequencies (or frequency range) were known, but the optimum acoustic impedance and optimum liner placement were typically not known. For these cases, the maximum available surface was used and a c-impedance was targeted based on the assumption the sound field impinges on the surface at normal incidence. This choice proved fruitful for every application. An impedance prediction model was used to design variable-depth liner configurations, and a graphical design code (ILIAD) was developed to aid in this process. The ability to build increasingly complex liner configurations via additive manufacturing was key, such that multiple designs could quickly be tested in a normal incidence impedance tube. The Two-Thickness Method was used to evaluate available bulk materials, such that bulk liners could also be considered for each application. These novel liner concepts provide sufficient noise reduction to warrant further investigations.
Preliminary structural design of composite main rotor blades for minimum weight
NASA Technical Reports Server (NTRS)
Nixon, Mark W.
1987-01-01
A methodology is developed to perform minimum weight structural design for composite or metallic main rotor blades subject to aerodynamic performance, material strength, autorotation, and frequency constraints. The constraints and load cases are developed such that the final preliminary rotor design will satisfy U.S. Army military specifications, as well as take advantage of the versatility of composite materials. A minimum weight design is first developed subject to satisfying the aerodynamic performance, strength, and autorotation constraints for all static load cases. The minimum weight design is then dynamically tuned to avoid resonant frequencies occurring at the design rotor speed. With this methodology, three rotor blade designs were developed based on the geometry of the UH-60A Black Hawk titanium-spar rotor blade. The first design is of a single titanium-spar cross section, which is compared with the UH-60A Black Hawk rotor blade. The second and third designs use single and multiple graphite/epoxy-spar cross sections. These are compared with the titanium-spar design to demonstrate weight savings from use of this design methodology in conjunction with advanced composite materials.
System importance measures: A new approach to resilient systems-of-systems
NASA Astrophysics Data System (ADS)
Uday, Payuna
Resilience is the ability to withstand and recover rapidly from disruptions. While this attribute has been the focus of research in several fields, in the case of system-of-systems (SoSs), addressing resilience is particularly interesting and challenging. As infrastructure SoSs, such as power, transportation, and communication networks, grow in complexity and interconnectivity, measuring and improving the resilience of these SoSs is vital in terms of safety and providing uninterrupted services. The characteristics of systems-of-systems make analysis and design of resilience challenging. However, these features also offer opportunities to make SoSs resilient using unconventional methods. In this research, we present a new approach to the process of resilience design. The core idea behind the proposed design process is a set of system importance measures (SIMs) that identify systems crucial to overall resilience. Using the results from the SIMs, we determine appropriate strategies from a list of design principles to improve SoS resilience. The main contribution of this research is the development of an aid to design that provides specific guidance on where and how resources need to be targeted. Based on the needs of an SoS, decision-makers can iterate through the design process to identify a set of practical and effective design improvements. We use two case studies to demonstrate how the SIM-based design process can inform decision-making in the context of SoS resilience. The first case study focuses on a naval warfare SoS and describes how the resilience framework can leverage existing simulation models to support end-to-end design. We proceed through stages of the design approach using an agent-based model (ABM) that enables us to demonstrate how simulation tools and analytical models help determine the necessary inputs for the design process and, subsequently, inform decision-making regarding SoS resilience. The second case study considers the urban transportation network in Boston. This case study focuses on interpreting the results of the resilience framework and on describing how they can be used to guide design choices in large infrastructure networks. We use different resilience maps to highlight the range of design-related information that can be obtained from the framework. Specific advantages of the SIM-based resilience design include: (1) incorporates SoS- specific features within existing risk-based design processes - the SIMs determine the relative importance of different systems based on their impacts on SoS-level performance, and suggestions for resilience improvement draw from design options that leverage SoS- specific characteristics, such as the ability to adapt quickly (such as add new systems or re-task existing ones) and to provide partial recovery of performance in the aftermath of a disruption; (2) allows rapid understanding of different areas of concern within the SoS - the visual nature of the resilience map (a key outcome of the SIM analysis) provides a useful way to summarize the current resilience of the SoS as well as point to key systems of concern; and (3) provides a platform for multiple analysts and decision- makers to study, modify, discuss and document options for SoS.
Alonso, Joan Francesc; Romero, Sergio; Mañanas, Miguel Ángel; Rojas, Mónica; Riba, Jordi; Barbanoj, Manel José
2015-10-01
The identification of the brain regions involved in the neuropharmacological action is a potential procedure for drug development. These regions are commonly determined by the voxels showing significant statistical differences after comparing placebo-induced effects with drug-elicited effects. LORETA is an electroencephalography (EEG) source imaging technique frequently used to identify brain structures affected by the drug. The aim of the present study was to evaluate different methods for the correction of multiple comparisons in the LORETA maps. These methods which have been commonly used in neuroimaging and also simulated studies have been applied on a real case of pharmaco-EEG study where the effects of increasing benzodiazepine doses on the central nervous system measured by LORETA were investigated. Data consisted of EEG recordings obtained from nine volunteers who received single oral doses of alprazolam 0.25, 0.5, and 1 mg, and placebo in a randomized crossover double-blind design. The identification of active regions was highly dependent on the selected multiple test correction procedure. The combined criteria approach known as cluster mass was useful to reveal that increasing drug doses led to higher intensity and spread of the pharmacologically induced changes in intracerebral current density.
Lancioni, Giulio E; Singh, Nirbhay N; O'Reilly, Mark F; Sigafoos, Jeff; Alberti, Gloria; Perilli, Viviana; Oliva, Doretta; Buono, Serafino
2014-09-01
Three microswitch-aided programs were assessed in three single-case studies to enhance physical exercise or ambulation in participants with multiple disabilities. Study I was aimed at helping a woman who tended to have the head bending forward and the arms down to exercise a combination of appropriate head and arms movements. Study II was aimed at promoting ambulation continuity with a man who tended to have ambulation breaks. Study III was aimed at promoting ambulation with appropriate foot position in a girl who usually showed toe walking. The experimental designs of the studies consisted of a multiple probe across responses (Study I), an ABAB sequence (Study II), and an ABABB(1) sequence (Study III). The last phase of each study was followed by a post-intervention check. The microswitches monitored the target responses selected for the participants and triggered a computer system to provide preferred stimuli contingent on those responses during the intervention phases of the studies. Data showed that the programs were effective with each of the participants who learned to exercise head and arms movements, increased ambulation continuity, and acquired high levels of appropriate foot position during ambulation, respectively. The positive performance levels were retained during the post-intervention checks. The discussion focused on (a) the potential of technology-aided programs for persons with multiple disabilities and (b) the need of replication studies to extend the evidence available in the area. Copyright © 2014 Elsevier Ltd. All rights reserved.
Nijmeijer, Karlijn J; Huijsman, Robbert; Fabbricotti, Isabelle N
2014-11-02
Business format franchising is an organizational form that originates from the business sector. It is increasingly used in healthcare, being a promising organizational form for improving the competitiveness and efficiency of organizations, the quality of care, and the professional work environment. However, evidence is lacking concerning how these healthcare franchises should be designed to actually deliver the promised benefits. This study explores how the design of the central element in franchising, the business format (i.e., brand name, support systems, specification of the products and services), helps or hinders the achievement of positive results. A qualitative comparative embedded case study was conducted. The cases focused on three Dutch healthcare franchises providing mental healthcare, hospital care and care for the intellectually disabled. The data were collected through document analyses, observations, and 96 in-depth, semi-structured interviews with franchisors and unit actors (franchisees, unit managers, professionals). The interviews were recorded and transcribed verbatim. A conceptual model based on a systematic review of studies in other industries was used as an initial method for coding the data. New inductive codes were used to enrich and extend the analysis. The data were subjected to within-case and cross-case comparative thematic analyses. Different business format designs have different effects on results, as perceived by franchisors and unit actors. The analysis revealed how this variation in perceived effects can be explained by different dynamics with regard to system-wide adaptation, local adaptation, professionals' resistance to change, ease of knowledge sharing, bureaucracy, overhead, uniform brand presentation, accelerating effects and reliable performance levels. The analysis resulted in a new typology of four types of business formats, showing how combinations of business format elements facilitate or hinder the achievement of different types of results. Practitioners using healthcare franchising as a model to improve client-related, strategic, organizational and professional results should carefully consider how to design their business format in order to facilitate the achievement of desired results. The developed typology can be used as a starting point for these practitioners and as a basis for future scholarly research. Further quantitative research is recommended to confirm the results.
Making a Case for a Blended Approach: The Need for The Design-Based Case Study
ERIC Educational Resources Information Center
Deaton, Cynthia C. M.; Malloy, Jacquelynn A.
2017-01-01
Design-based case studies address research questions that involve instructional innovations within a bounded system. This blend of case study and design-based research provides a systematic approach to examining instructional innovations that are bounded by perspective, context, and time. Design-based case studies provide a framework for engaging…
Design principles of a cooperative robot controller
NASA Technical Reports Server (NTRS)
Hayward, Vincent; Hayati, Samad
1987-01-01
The paper describes the design of a controller for cooperative robots being designed at McGill University in a collaborative effort with the Jet Propulsion Laboratory. The first part of the paper discusses the background and motivation for multiple arm control. Then, a set of programming primitives, which are based on the RCCL system and which permit a programmer to specify cooperative tasks are described. The first group of primitives are motion primitives which specify asynchronous motions, master/slave motions, and cooperative motions. In the context of cooperative robots, trajectory generation issues will be discussed and the implementation described. A second set of primitives provides for the specification of spatial relationships. The relations between programming and control in the case of multiple robot are examined. Finally, the paper describes the allocation of various tasks among a set of microprocessors sharing a common bus.
Cultural evolution of military camouflage.
Talas, Laszlo; Baddeley, Roland J; Cuthill, Innes C
2017-07-05
While one has evolved and the other been consciously created, animal and military camouflage are expected to show many similar design principles. Using a unique database of calibrated photographs of camouflage uniform patterns, processed using texture and colour analysis methods from computer vision, we show that the parallels with biology are deeper than design for effective concealment. Using two case studies we show that, like many animal colour patterns, military camouflage can serve multiple functions. Following the dissolution of the Warsaw Pact, countries that became more Western-facing in political terms converged on NATO patterns in camouflage texture and colour. Following the break-up of the former Yugoslavia, the resulting states diverged in design, becoming more similar to neighbouring countries than the ancestral design. None of these insights would have been obtained using extant military approaches to camouflage design, which focus solely on concealment. Moreover, our computational techniques for quantifying pattern offer new tools for comparative biologists studying animal coloration.This article is part of the themed issue 'Animal coloration: production, perception, function and application'. © 2017 The Author(s).
Frömke, Cornelia; Hothorn, Ludwig A; Kropf, Siegfried
2008-01-27
In many research areas it is necessary to find differences between treatment groups with several variables. For example, studies of microarray data seek to find a significant difference in location parameters from zero or one for ratios thereof for each variable. However, in some studies a significant deviation of the difference in locations from zero (or 1 in terms of the ratio) is biologically meaningless. A relevant difference or ratio is sought in such cases. This article addresses the use of relevance-shifted tests on ratios for a multivariate parallel two-sample group design. Two empirical procedures are proposed which embed the relevance-shifted test on ratios. As both procedures test a hypothesis for each variable, the resulting multiple testing problem has to be considered. Hence, the procedures include a multiplicity correction. Both procedures are extensions of available procedures for point null hypotheses achieving exact control of the familywise error rate. Whereas the shift of the null hypothesis alone would give straight-forward solutions, the problems that are the reason for the empirical considerations discussed here arise by the fact that the shift is considered in both directions and the whole parameter space in between these two limits has to be accepted as null hypothesis. The first algorithm to be discussed uses a permutation algorithm, and is appropriate for designs with a moderately large number of observations. However, many experiments have limited sample sizes. Then the second procedure might be more appropriate, where multiplicity is corrected according to a concept of data-driven order of hypotheses.
Caring and its role in effective life science teaching: A case study
NASA Astrophysics Data System (ADS)
Seals, Mark A.
The focus of this inquiry was to explore, analyze, and describe the reciprocity of caring as it is embedded in and shapes the culture of the high school life science classroom. The data collection and analysis was guided by the theoretical underpinnings of phenomenology and heuristics, while following a multiple case study design. The case study involved two life science teachers, one male (Mr. Gene Fischer) and one female (Mrs. Carrie Sanders), who are perceived to be effective and caring educators. They were selected purposely, along with two of their classes (an upper level genetic/molecular biology class and a lower level freshman biology course), which included 82 students. Data were collected in the form of field notes, videotapes and documents at each site. Grounded theory generated from the study was analyzed by following a case analysis (Merriam, 1988), and cross-case analysis (Merriam, 1988) approach, while also using the tenets of the constant comparative method by Glaser and Strauss (1967). By studying experienced, effective and caring teachers (and their students) over time, it was hoped to expand the extant theory about the ethic of care to better understanding the impact caring has in a variety of teaching and learning situations within the life science classroom.
An Exploration of Infant and Toddler Child Care Consultation: A Multiple Case Study
ERIC Educational Resources Information Center
John, Christine Marie
2015-01-01
This qualitative, multiple case study was an exploration of the professional development (PD) experience of consultation as it occurred within infant and toddler child care settings. Consultation is dependent upon the establishment of a relationship between the consultant and the consultee and offers opportunities for professional growth and…
Understanding Teacher Perceptions in a Professional Development Program for a Middle Grade Science
NASA Astrophysics Data System (ADS)
Deloney, Dericka B.
The standards-based framework requires teachers to evaluate and in some cases change their instructional approach to more student-centered and inquiry-based in an effort to help students meet the standards. The rationale for this study was to determine the skills needed for teachers to be effective in a standard-based, problem-based learning (PBL) constructivist classroom. Traditionally, teachers in this school district transitioning from teacher to student-centered classrooms need new skills when implementing this type of instruction. A qualitative case study design served to highlight the research questions for this project study. The participants in this study participated in data collection activities that include a multiple-choice survey, an interview, and the sharing of their PBL units. Artifacts, professional development teaching resources, from the workshop added credence to the survey and interview responses. The findings from each research question addressed the teachers' perception of their understanding and the obstacles of instructional design, development, and implementation the participants encountered. The results of this study indicated that teachers had problems with designing and implementing this instructional strategy due to lack of time and resources. This data assisted the development of district specific PBL sustainable professional development program that could be adaptable to other curriculums and school systems. Social change resulting from this study could include a framework for developing K-12 professional development as well as instructional programs that incorporates PBL curriculum design to enhance the student's inquiry, problem-solving, and decision-making skills that in turn should change their academic achievement and scores on high stakes test in science.
[Association of Kaposi sarcoma--multiple myeloma. A new case].
Cohen, J D; Thomas, E; Garnier, N; Hellier, I; Durand, L; Guilhou, J J; Baldet, P; Blotman, F
2000-11-01
Kaposi's disease is an angiogenic multifocal cancer process that has several forms, namely Mediterranean, African, HIV-associated, and secondary to a preexisting immunodepressive state (hematological disorder, corticosteroid therapy, immunodepressive treatment). Whatever its form, Kaposi's sarcoma is probably associated with a chronic viral human herpes type 8 infection (HHV8). This virus has been implicated in the pathogenesis of multiple myeloma (17 cases recorded to date). In the present study, a further case of Kaposi's sarcoma associated with multiple myeloma has been reported. However, Epstein-Barr virus, cytomegalovirus, hepatitis B and C, HIV and HHV8 serologies were negative. Radiotherapy on the lower limbs was initiated. It is concluded that HHV8 does not appear to play a pathogenic role in cases of multiple myeloma, given the rarity of the association between Kaposi's sarcoma/multiple myeloma/HHV8.
NASA Astrophysics Data System (ADS)
Bellagamba, Laura; Denaro, Simona; Kern, Jordan; Giuliani, Matteo; Castelletti, Andrea; Characklis, Gregory
2016-04-01
Growing water demands and more frequent and severe droughts are increasingly challenging water management in many regions worldwide, exacerbating water disputes and reducing the space for negotiated agreements at the catchment scale. In the lack of a centralized controller, the design and deployment of coordination and/or regulatory mechanisms is a way to improve system-wide efficiency while preserving the distributed nature of the decision making setting, and facilitating cooperation among institutionally independent decision-makers. Recent years have witnessed an increased interest in index-based insurance contracts as mechanisms for sharing hydro-meteorological risk in complex and heterogeneous decision making context (e.g. multiple stakeholders and institutionally independent decision makers). In this study, we explore the potential for index-based insurance contracts to mitigate the conflict in a water system characterized by (political) power asymmetry between hydropower companies upstream and farmers downstream. The Lake Como basin in the Italian Alps is considered as a case study. We generated alternative regulatory mechanisms in the form of minimum release constraints to the hydropower facilities, and designed an insurance contract for hedging against hydropower relative revenue losses. The fundamental step in designing this type of insurance contracts is the identification of a suitable index, which triggers the payouts as well as the payout function, defined by strike level and slope (e.g., euros/index unit). A portfolio of index-based contracts was designed for the case study and evaluated in terms of revenue floor, basis risk and revenue fluctuation around the mean, both with and without insurance. Over the long term, the insurance proved to be capable to keep the minimum revenue above a specified level while providing a greater certainty on the revenue trend. This result shows the possibility to augment farmer's supply with little loss for hydropower companies, thus helping in mitigating the conflict between the stakeholders.
Modifiable Neighborhood Features Associated With Adolescent Homicide
Culyba, Alison J.; Jacoby, Sara F.; Richmond, Therese S.; Fein, Joel A.; Hohl, Bernadette C.; Branas, Charles C.
2016-01-01
IMPORTANCE Homicide is a leading cause of adolescent mortality. To our knowledge, relatively little has been studied in terms of the association between environmental neighborhood features, such as streets, buildings, and natural surroundings, and severe violent injury among youth. OBJECTIVE To assess associations between environmental neighborhood features and adolescent homicide in order to identify targets for future place-based interventions. DESIGN, SETTING, AND PARTICIPANTS Population-based case-control study conducted in Philadelphia, Pennsylvania, from April 15, 2008, to March 31, 2014. We identified adolescents who died by homicide at 13 to 20 years of age from 2010 to 2012 while residing in Philadelphia. We used incidence-density sampling and random-digit dialing to recruit control participants ages 13 to 20 years matched on sex and indoor-outdoor location at the time of each index case participant’s homicide. EXPOSURES To obtain environmental data about modifiable features that were present in the immediate surroundings of our case and control participants, blinded field researchers used standardized techniques to photograph case and control participant outdoor locations. Photographic data were stitched together to create 360° panoramic images that were coded for 60 elements of the visible environment. MAIN OUTCOME AND MEASURE Adolescent homicide. RESULTS We enrolled 143 homicide case participants (mean [SD] age, 18.4 [1.5] years) and 155 matched control participants (mean [SD] age, 17.2 [2.1] years) who were both outdoors at the time of the homicide. In adjusted analyses, multiple features of Philadelphia streets, buildings, and natural surroundings were associated with adolescent homicide. The presence of street lighting (odds ratio [OR], 0.24; 95% CI, 0.09-0.70), illuminated walk/don’t walk signs (OR, 0.16; 95% CI, 0.03-0.92), painted marked crosswalks (OR, 0.17; 95% CI, 0.04-0.63), public transportation (OR, 0.13; 95% CI, 0.03-0.49), parks (OR, 0.09; 95% CI, 0.01-0.88), and maintained vacant lots (OR, 0.17; 95% CI, 0.03-0.81) were significantly associated with decreased odds of homicide. The odds of homicide were significantly higher in locations with stop signs (OR, 4.34; 95% CI, 1.40-13.45), security bars/gratings on houses (OR, 9.23; 95% CI, 2.45-34.80), and private bushes/plantings (OR, 3.44; 95% CI, 1.18-10.01). CONCLUSIONS AND RELEVANCE Using a population-based case-control design, we identified multiple modifiable environmental features that might be targeted in future randomized intervention trials designed to reduce youth violence by improving neighborhood context. PMID:26954939
NASA Technical Reports Server (NTRS)
1977-01-01
Multiple access techniques (FDMA, CDMA, TDMA) for the mobile user and attempts to identify the current best technique are discussed. Traffic loading is considered as well as voice and data modulation and spacecraft and system design. Emphasis is placed on developing mobile terminal cost estimates for the selected design. In addition, design examples are presented for the alternative techniques of multiple access in order to compare with the selected technique.
Al-Hallaq, Hania A; Chmura, Steven; Salama, Joseph K; Winter, Kathryn A; Robinson, Clifford G; Pisansky, Thomas M; Borges, Virginia; Lowenstein, Jessica R; McNulty, Susan; Galvin, James M; Followill, David S; Timmerman, Robert D; White, Julia R; Xiao, Ying; Matuszak, Martha M
In 2014, the NRG Oncology Group initiated the first National Cancer Institute-sponsored, phase 1 clinical trial of stereotactic body radiation therapy (SBRT) for the treatment of multiple metastases in multiple organ sites (BR001; NCT02206334). The primary endpoint is to test the safety of SBRT for the treatment of 2 to 4 multiple lesions in several anatomic sites in a multi-institutional setting. Because of the technical challenges inherent to treating multiple lesions as their spatial separation decreases, we present the technical requirements for NRG-BR001 and the rationale for their selection. Patients with controlled primary tumors of breast, non-small cell lung, or prostate are eligible if they have 2 to 4 metastases distributed among 7 extracranial anatomic locations throughout the body. Prescription and organ-at-risk doses were determined by expert consensus. Credentialing requirements include (1) irradiation of the Imaging and Radiation Oncology Core phantom with SBRT, (2) submitting image guided radiation therapy case studies, and (3) planning the benchmark. Guidelines for navigating challenging planning cases including assessing composite dose are discussed. Dosimetric planning to multiple lesions receiving differing doses (45-50 Gy) and fractionation (3-5) while irradiating the same organs at risk is discussed, particularly for metastases in close proximity (≤5 cm). The benchmark case was selected to demonstrate the planning tradeoffs required to satisfy protocol requirements for 2 nearby lesions. Examples of passing benchmark plans exhibited a large variability in plan conformity. NRG-BR001 was developed using expert consensus on multiple issues from the dose fractionation regimen to the minimum image guided radiation therapy guidelines. Credentialing was tied to the task rather than the anatomic site to reduce its burden. Every effort was made to include a variety of delivery methods to reflect current SBRT technology. Although some simplifications were adopted, the successful completion of this trial will inform future designs of both national and institutional trials and would allow immediate clinical adoption of SBRT trials for oligometastases. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.
Converse, S.J.; Kendall, W.L.; Doherty, P.F.; Naughton, M.B.; Hines, J.E.; Thomson, David L.; Cooch, Evan G.; Conroy, Michael J.
2009-01-01
For many animal populations, one or more life stages are not accessible to sampling, and therefore an unobservable state is created. For colonially-breeding populations, this unobservable state could represent the subset of adult breeders that have foregone breeding in a given year. This situation applies to many seabird populations, notably albatrosses, where skipped breeders are either absent from the colony, or are present but difficult to capture or correctly assign to breeding state. Kendall et al. have proposed design strategies for investigations of seabird demography where such temporary emigration occurs, suggesting the use of the robust design to permit the estimation of time-dependent parameters and to increase the precision of estimates from multi-state models. A traditional robust design, where animals are subject to capture multiple times in a sampling season, is feasible in many cases. However, due to concerns that multiple captures per season could cause undue disturbance to animals, Kendall et al. developed a less-invasive robust design (LIRD), where initial captures are followed by an assessment of the ratio of marked-to-unmarked birds in the population or sampled plot. This approach has recently been applied in the Northwestern Hawaiian Islands to populations of Laysan (Phoebastria immutabilis) and black-footed (P. nigripes) albatrosses. In this paper, we outline the LIRD and its application to seabird population studies. We then describe an approach to determining optimal allocation of sampling effort in which we consider a non-robust design option (nRD), and variations of both the traditional robust design (RD), and the LIRD. Variations we considered included the number of secondary sampling occasions for the RD and the amount of total effort allocated to the marked-to-unmarked ratio assessment for the LIRD. We used simulations, informed by early data from the Hawaiian study, to address optimal study design for our example cases. We found that the LIRD performed as well or nearly as well as certain variations of the RD in terms of root mean square error, especially when relatively little of the total effort was allocated to the assessment of the marked-to-unmarked ratio versus to initial captures. For the RD, we found no clear benefit of using 2, 4, or 6 secondary sampling occasions per year, though this result will depend on the relative effort costs of captures versus recaptures and on the length of the study. We also found that field-readable bands, which may be affixed to birds in addition to standard metal bands, will be beneficial in longer-term studies of albatrosses in the Northwestern Hawaiian Islands. Field-readable bands reduce the effort cost of recapturing individuals, and in the long-term this cost reduction can offset the additional effort expended in affixing the bands. Finally, our approach to determining optimal study design can be generally applied by researchers, with little seed data, to design their studies at the outset.
Coding Response to a Case-Mix Measurement System Based on Multiple Diagnoses
Preyra, Colin
2004-01-01
Objective To examine the hospital coding response to a payment model using a case-mix measurement system based on multiple diagnoses and the resulting impact on a hospital cost model. Data Sources Financial, clinical, and supplementary data for all Ontario short stay hospitals from years 1997 to 2002. Study Design Disaggregated trends in hospital case-mix growth are examined for five years following the adoption of an inpatient classification system making extensive use of combinations of secondary diagnoses. Hospital case mix is decomposed into base and complexity components. The longitudinal effects of coding variation on a standard hospital payment model are examined in terms of payment accuracy and impact on adjustment factors. Principal Findings Introduction of the refined case-mix system provided incentives for hospitals to increase reporting of secondary diagnoses and resulted in growth in highest complexity cases that were not matched by increased resource use over time. Despite a pronounced coding response on the part of hospitals, the increase in measured complexity and case mix did not reduce the unexplained variation in hospital unit cost nor did it reduce the reliance on the teaching adjustment factor, a potential proxy for case mix. The main implication was changes in the size and distribution of predicted hospital operating costs. Conclusions Jurisdictions introducing extensive refinements to standard diagnostic related group (DRG)-type payment systems should consider the effects of induced changes to hospital coding practices. Assessing model performance should include analysis of the robustness of classification systems to hospital-level variation in coding practices. Unanticipated coding effects imply that case-mix models hypothesized to perform well ex ante may not meet expectations ex post. PMID:15230940
ERIC Educational Resources Information Center
House, Collette R.
2016-01-01
School leaders commonly face issues of loneliness, isolation, burnout, and depression. The purpose of this qualitative multiple-case study was to explore self-initiated peer support group participation for professional impact and personal impact on school leaders facing issues of loneliness, isolation, stress, and burnout. This study provides an…