Alternating treatments design: one strategy for comparing the effects of two treatments in a single subject.

PubMed Central

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

Design and modeling of sustainable bioethanol supply chain by minimizing the total ecological footprint in life cycle perspective.

PubMed

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.

Team effectiveness in academic medical libraries: a multiple case study*

PubMed Central

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

Adaptive graph-based multiple testing procedures

PubMed Central

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

Using case study within a sequential explanatory design to evaluate the impact of specialist and advanced practice roles on clinical outcomes: the SCAPE study.

PubMed

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.

Organizational Learning from near Misses, Incidents, Accidents, and Fatalities: A Multiple Case Study of the USA Amusement Industry

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.…

Towards high performing hospital enterprise systems: an empirical and literature based design framework

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.

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...

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…

Design of a clinical notification system.

PubMed

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.

78 FR 66941 - Design Considerations for Pivotal Clinical Investigations for Medical Devices; Guidance for...

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...

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…

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…

An Examination of Fluoxetine for the Treatment of Selective Mutism Using a Nonconcurrent Multiple-Baseline Single-Case Design Across 5 Cases.

PubMed

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.

Enhancing the hermeneutic single-case efficacy design: Bridging the research-practice gap.

PubMed

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.

Design and Development of an Online Video Enhanced Case-Based Learning Environment for Teacher Education

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…

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…

A retrospective likelihood approach for efficient integration of multiple omics factors in case-control association studies.

PubMed

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.

Case analysis online: a strategic management case model for the health industry.

PubMed

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.

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 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…

Effects of a Strategic Intervention with iPad Practice on the Multiplication Fact Performance of Fifth-Grade Students with Learning Disabilities

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…

Therapeutic Horseback Riding Outcomes of Parent-Identified Goals for Children with Autism Spectrum Disorder: An ABA′ Multiple Case Design Examining Dosing and Generalization to the Home and Community

PubMed Central

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

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…

Understanding the Relationship between Teacher Behavior and Motivation in Students with Acquired Deafblindness

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…

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…

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…

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…

Learning from Multiple Cases: A New Paradigm for Investigating the Effects of Clinical Experience on Knowledge Restructuring and Knowledge Acquisition.

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…

Course Design and Delivery Specifications as a Tool for Ensuring Quality in an Online Training Program

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…

Undertaking Individual Transdisciplinary PhD Research for Sustainable Development: Case Studies from South Africa

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…

What Are the Teachers' Experiences When Implementing the Curriculum for Agricultural Science Education?

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…

Lessons for Co-Innovation in Agricultural Innovation Systems: A Multiple Case Study Analysis and a Conceptual Model

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…

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.

PubMed

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.

Exploring the Potential of Smartphones and Tablets for Performance Support in Food Chemistry Laboratory Classes

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.

Developing the DESCARTE Model: The Design of Case Study Research in Health Care.

PubMed

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.

"Just Having a Job": Career Advancement for Low-Wage Workers with Intellectual and Developmental Disabilities

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…

Designing for Multiple Stakeholder Interests within the Humanitarian Market: The Case of Off-Grid Energy Devices

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…

Effect of Rehabilitation Technology Services on Vocational Rehabilitation Outcomes of Individuals with Multiple Sclerosis

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…

The Twenty-First Century Multiple Generation Workforce: Overlaps and Differences but Also Challenges and Benefits

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,…

Systematic procedure for designing processes with multiple environmental objectives.

PubMed

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.

Manipulating the optical properties of symmetrically branched Au/Pd nanocrystals through interior design.

PubMed

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.

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…

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…

Concerns, Use of Time, and the Intersections of Leadership: Case Study of Two Charter School Principals

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,…

Multiple imputation of missing data in nested case-control and case-cohort studies.

PubMed

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.

Mobile Technology in Second Language Classrooms: Insights into Its Uses, Pedagogical Implications, and Teacher Beliefs

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,…

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…

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…

76 FR 13137 - Equity Assistance Centers Program; Office of Elementary and Secondary Education; Overview...

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...

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.

Brain MRI volumetry in a single patient with mild traumatic brain injury.

PubMed

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.

A Design-Based Research Case Study Documenting a Constructivist ID Process and Instructional Solution for a Cross-Cultural Workforce

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…

Worst-Case Energy Efficiency Maximization in a 5G Massive MIMO-NOMA System.

PubMed

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

PubMed Central

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

The Impact of Video Case Content on Preservice Elementary Teachers' Decision-Making and Conceptions of Effective Science Teaching

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…

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…

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)…

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…

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…

A comprehensive grid to evaluate case management's expected effectiveness for community-dwelling frail older people: results from a multiple, embedded case study.

PubMed

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.

Freestyle multiple propeller flap reconstruction (jigsaw puzzle approach) for complicated back defects.

PubMed

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.

Analysis of components of variance in multiple-reader studies of computer-aided diagnosis with different tasks

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.

Distributed finite-time containment control for double-integrator multiagent systems.

PubMed

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.

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…

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…

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,…

Alternative approaches to analytical designs in occupational injury epidemiology.

PubMed

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.

TH-C-19A-01: Analytic Design Method to Make a 2D Planar, Segmented Ion Chamber Water-Equivalent for Proton Dose Measurements

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

Bayesian design criteria: computation, comparison, and application to a pharmacokinetic and a pharmacodynamic model.

PubMed

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.

Multiple Imputation in Two-Stage Cluster Samples Using The Weighted Finite Population Bayesian Bootstrap.

PubMed

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.

Multiple Imputation in Two-Stage Cluster Samples Using The Weighted Finite Population Bayesian Bootstrap

PubMed Central

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 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…

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…

Multistate approaches in computational protein design

PubMed Central

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

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)

Statistical innovations in diagnostic device evaluation.

PubMed

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.

Virtual patients: the influence of case design and teamwork on students' perception and knowledge - a pilot study.

PubMed

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.

Education Leaders' Decision-Making Processes about Educational Facilities in a University Multiple Stakeholder Environment

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…

An Examination of Instructional Interactions between Volunteer-Tutors and Students Who Show Differential Gains in Reading Comprehension

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…

Writing Simple Sentences and Descriptive Paragraphs: Effects of an Intervention on Adolescents with Writing Difficulties

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…

The Impact of a Professional Learning Intervention Designed to Enhance Year Six Students' Computational Estimation Performance

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…

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…

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.

Data Base Design with GIS in Ecosystem Based Multiple Use Forest Management in Artvin, Turkey: A Case Study in Balcı Forest Management Planning Unit.

PubMed

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.

Extending Beowulf Clusters

USGS Publications Warehouse

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.

On the use of Different Methodologies in Cognitive Neuropsychology: Drink Deep and from Several Sources

PubMed Central

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

Primary care physicians’ perspectives on facilitating older patients’ access to community support services

PubMed Central

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

Utilising family-based designs for detecting rare variant disease associations.

PubMed

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.

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…

Designing Meaning with Multiple Media Sources: A Case Study of an Eight-Year-Old Student's Writing Processes

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…

A Multiple Case Study: The Effect of Professional Development on Teachers' Perceived Ability to Foster Resilience

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…

Naturally-Emerging Technology-Based Leadership Roles in Three Independent Schools: A Social Network-Based Case Study Using Fuzzy Set Qualitative Comparative Analysis

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…

School Administrators Who Serve in Different Institutions Ethical Dilemmas and Their Attitudes towards These Dilemmas

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…

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.

Real life juvenile toxicity case studies: the good, the bad and the ugly.

PubMed

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.

Multiple imputation methods for bivariate outcomes in cluster randomised trials.

PubMed

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.

Optimal design of compact and connected nature reserves for multiple species.

PubMed

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.

Bayesian Estimation of Pneumonia Etiology: Epidemiologic Considerations and Applications to the Pneumonia Etiology Research for Child Health Study.

PubMed

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.

Music therapy in the treatment of multiple sclerosis: a comprehensive literature review.

PubMed

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.

Multiple Ejection Effects Analysis

DTIC Science & Technology

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

The impact of embedding multiple modes of representation on student construction of chemistry knowledge

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.

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

Virtual patients: the influence of case design and teamwork on students’ perception and knowledge – a pilot study

PubMed Central

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

PathCase-SB architecture and database design

PubMed Central

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

Portraits of Pre-Service Classroom Teachers: Exploring Intentions to Integrate Music through the Lens of the Theory of Planned Behavior

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…

Teacher Candidates and Latina/o English Learners at Fenton Elementary School: The Role of Early Clinical Experiences in Urban Teacher Education

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…

Relationships between the generalized functional method and other methods of nonimaging optical design.

PubMed

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

Use of Comparative Case Study Methodology for US Public Health Policy Analysis: A Review.

PubMed

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.

Executive Beliefs About the Critical Success Factors In Defining, Designing, Developing and Delivering e-Learning For Adult Professional Development in Corporations

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…

Challenges to Providing End-of-Life Care to Low-Income Elders with Advanced Chronic Disease: Lessons Learned from a Model Program

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…

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.

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.

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)

Young Adult and Usual Adult Body Mass Index and Multiple Myeloma Risk: A Pooled Analysis in the International Multiple Myeloma Consortium (IMMC).

PubMed

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.

Therapeutic assessment for preadolescent boys with oppositional defiant disorder: a replicated single-case time-series design.

PubMed

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.

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.

Options for biodiversity conservation in managed forest landscapes of multiple ownerships in Oregon and Washington, USA.

Treesearch

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.

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...

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…

EAT-UP™ Family-Centered Feeding Intervention to Promote Food Acceptance and Decrease Challenging Behaviors: A Single-Case Experimental Design Replicated across Three Families of Children with Autism Spectrum Disorder

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…

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.

Methodology Series Module 2: Case-control Studies.

PubMed

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.

Designing a mixture experiment when the components are subject to a nonlinear multiple-component constraint

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

Automated Big Data Analysis in Bottom-up and Targeted Proteomics

PubMed Central

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.

Left ventricular assist device malfunction: a systematic approach to diagnosis.

PubMed

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.

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.

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.

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.

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,…

How to Construct a Mixed Methods Research Design.

PubMed

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.

Sparse and optimal acquisition design for diffusion MRI and beyond

PubMed Central

Koay, Cheng Guan; Özarslan, Evren; Johnson, Kevin M.; Meyerand, M. Elizabeth

2012-01-01

Purpose: Diffusion magnetic resonance imaging (MRI) in combination with functional MRI promises a whole new vista for scientists to investigate noninvasively the structural and functional connectivity of the human brain—the human connectome, which had heretofore been out of reach. As with other imaging modalities, diffusion MRI data are inherently noisy and its acquisition time-consuming. Further, a faithful representation of the human connectome that can serve as a predictive model requires a robust and accurate data-analytic pipeline. The focus of this paper is on one of the key segments of this pipeline—in particular, the development of a sparse and optimal acquisition (SOA) design for diffusion MRI multiple-shell acquisition and beyond. Methods: The authors propose a novel optimality criterion for sparse multiple-shell acquisition and quasimultiple-shell designs in diffusion MRI and a novel and effective semistochastic and moderately greedy combinatorial search strategy with simulated annealing to locate the optimum design or configuration. The goal of the optimality criteria is threefold: first, to maximize uniformity of the diffusion measurements in each shell, which is equivalent to maximal incoherence in angular measurements; second, to maximize coverage of the diffusion measurements around each radial line to achieve maximal incoherence in radial measurements for multiple-shell acquisition; and finally, to ensure maximum uniformity of diffusion measurement directions in the limiting case when all the shells are coincidental as in the case of a single-shell acquisition. The approach taken in evaluating the stability of various acquisition designs is based on the condition number and the A-optimal measure of the design matrix. Results: Even though the number of distinct configurations for a given set of diffusion gradient directions is very large in general—e.g., in the order of 10232 for a set of 144 diffusion gradient directions, the proposed search strategy was found to be effective in finding the optimum configuration. It was found that the square design is the most robust (i.e., with stable condition numbers and A-optimal measures under varying experimental conditions) among many other possible designs of the same sample size. Under the same performance evaluation, the square design was found to be more robust than the widely used sampling schemes similar to that of 3D radial MRI and of diffusion spectrum imaging (DSI). Conclusions: A novel optimality criterion for sparse multiple-shell acquisition and quasimultiple-shell designs in diffusion MRI and an effective search strategy for finding the best configuration have been developed. The results are very promising, interesting, and practical for diffusion MRI acquisitions. PMID:22559620

Pathways to Identity: Aiding Law Enforcement in Identification Tasks With Visual Analytics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruce, Joseph R.; Scholtz, Jean; Hodges, Duncan

The nature of identity has changed dramatically in recent years, and has grown in complexity. Identities are defined in multiple domains: biological and psychological elements strongly contribute, but also biographical and cyber elements are necessary to complete the picture. Law enforcement is beginning to adjust to these changes, recognizing its importance in criminal justice. The SuperIdentity project seeks to aid law enforcement officials in their identification tasks through research of techniques for discovering identity traits, generation of statistical models of identity and analysis of identity traits through visualization. We present use cases compiled through user interviews in multiple fields, includingmore » law enforcement, as well as the modeling and visualization tools design to aid in those use cases.« less

Pathways to Identity. Using Visualization to Aid Law Enforcement in Identification Tasks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruce, Joseph R.; Scholtz, Jean; Hodges, Duncan

The nature of identity has changed dramatically in recent years and has grown in complexity. Identities are defined in multiple domains: biological and psychological elements strongly contribute, but biographical and cyber elements also are necessary to complete the picture. Law enforcement is beginning to adjust to these changes, recognizing identity’s importance in criminal justice. The SuperIdentity project seeks to aid law enforcement officials in their identification tasks through research of techniques for discovering identity traits, generation of statistical models of identity and analysis of identity traits through visualization. We present use cases compiled through user interviews in multiple fields, includingmore » law enforcement, and describe the modeling and visualization tools design to aid in those use cases.« less

Quality in School Environments: A Multiple Case Study of the Diagnosis, Design and Management of Environmental Quality in Five Elementary Schools in the Baltimore City Public Schools from an Action Research Perspective. Volumes I and II.

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…

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.

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.

Life cycle cost optimization of biofuel supply chains under uncertainties based on interval linear programming.

PubMed

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.

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…

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…

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,…

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…

Blissymbols and Manual Signs: A Multimodal Approach to Intervention in a Case of Multiple Disability.

ERIC Educational Resources Information Center

Hooper, Janice; And Others

1987-01-01

A multimodal intervention program designed for a nine-year-old with severe communication problems (secondary to cerebral palsy, receptive dysphasia, and auditory agnosia) combined manual signs and graphic symbols to help her communicate. The intensive, highly structured program had significant positive results. (Author/CB)

Reconstruction of massive facial avulsive injury, secondary to animal bite.

PubMed

Motamed, Sadrollah; Niazi, Feizollah; Moosavizadeh, Seyed Mehdi; Gholizade Pasha, Abdolhamid; Motamed, Ali

2014-02-01

Management of facial soft tissue trauma requires complex reconstruction surgery. Animal bite on face is a common cause of facial tissue trauma with severe destruction. Evaluation of unit involvement is the first effort, followed by designation of reconstruction. In this case, we performed multiple reconstruction options.

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…

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…

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…

Teaching with and through Teams: Student-Written, Instructor-Facilitated Case Writing and the Signatory Code

ERIC Educational Resources Information Center

Bailey, James; Sass, Mary; Swiercz, Paul M.; Seal, Craig; Kayes, D. Christopher

2005-01-01

Modern organizations prize teamwork. Management schools have responded to this reality by integrating teamwork into the curriculum. Two important challenges associated with integrating teams in the management classroom include (a) designing teamwork assignments that achieve multiple, sophisticated learning outcomes and (b) instruction in, and…

Building the School Nutrition Program Brand Personality within the School Setting

ERIC Educational Resources Information Center

Rushing, Keith; Asperin, Amelia Estepa

2012-01-01

Purpose/Objectives: The objectives of this project were to investigate the application of brand personality concepts in the school nutrition (SN) setting and to explore high school students' awareness and acceptance of these branding initiatives. Methods: An embedded, multiple-case replication design included structured interviews with SN…

Life cycle assessment based environmental impact estimation model for pre-stressed concrete beam bridge in the early design phase

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

Design, methodological issues and participation in a multiple sclerosis case-control study.

PubMed

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.

Electrodynamic multiple-scattering method for the simulation of optical trapping atop periodic metamaterials

NASA Astrophysics Data System (ADS)

Yannopapas, Vassilios; Paspalakis, Emmanuel

2018-07-01

We present a new theoretical tool for simulating optical trapping of nanoparticles in the presence of an arbitrary metamaterial design. The method is based on rigorously solving Maxwell's equations for the metamaterial via a hybrid discrete-dipole approximation/multiple-scattering technique and direct calculation of the optical force exerted on the nanoparticle by means of the Maxwell stress tensor. We apply the method to the case of a spherical polystyrene probe trapped within the optical landscape created by illuminating of a plasmonic metamaterial consisting of periodically arranged tapered metallic nanopyramids. The developed technique is ideally suited for general optomechanical calculations involving metamaterial designs and can compete with purely numerical methods such as finite-difference or finite-element schemes.

Global Moon Coverage via Hyperbolic Flybys

NASA Technical Reports Server (NTRS)

Buffington, Brent; Strange, Nathan; Campagnola, Stefano

2012-01-01

The scientific desire for global coverage of moons such as Jupiter's Galilean moons or Saturn's Titan has invariably led to the design of orbiter missions. These orbiter missions require a large amount of propellant needed to insert into orbit around such small bodies, and for a given launch vehicle, the additional propellant mass takes away from mass that could otherwise be used for scientific instrumentation on a multiple flyby-only mission. This paper will present methods--expanding upon techniques developed for the design of the Cassini prime and extended missions--to obtain near global moon coverage through multiple flybys. Furthermore we will show with proper instrument suite selection, a flyby-only mission can provide science return similar (and in some cases greater) to that of an orbiter mission.

Qualitative case study data analysis: an example from practice.

PubMed

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.

Precise Orbit Determination for LEO Spacecraft Using GNSS Tracking Data from Multiple Antennas

NASA Technical Reports Server (NTRS)

Kuang, Da; Bertiger, William; Desai, Shailen; Haines, Bruce

2010-01-01

To support various applications, certain Earth-orbiting spacecrafts (e.g., SRTM, COSMIC) use multiple GNSS antennas to provide tracking data for precise orbit determination (POD). POD using GNSS tracking data from multiple antennas poses some special technical issues compared to the typical single-antenna approach. In this paper, we investigate some of these issues using both real and simulated data. Recommendations are provided for POD with multiple GNSS antennas and for antenna configuration design. The observability of satellite position with multiple antennas data is compared against single antenna case. The impact of differential clock (line biases) and line-of-sight (up, along-track, and cross-track) on kinematic and reduced-dynamic POD is evaluated. The accuracy of monitoring the stability of the spacecraft structure by simultaneously performing POD of the spacecraft and relative positioning of the multiple antennas is also investigated.

Methodology Series Module 2: Case-control Studies

PubMed Central

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

Use of a mobile device in mental health rehabilitation: A clinical and comprehensive analysis of 11 cases.

PubMed

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.

Call sign intelligibility improvement using a spatial auditory display

NASA Technical Reports Server (NTRS)

Begault, Durand R.

1994-01-01

A spatial auditory display was designed for separating the multiple communication channels usually heard over one ear to different virtual auditory positions. The single 19 foot rack mount device utilizes digital filtering algorithms to separate up to four communication channels. The filters use four different binaural transfer functions, synthesized from actual outer ear measurements, to impose localization cues on the incoming sound. Hardware design features include 'fail-safe' operation in the case of power loss, and microphone/headset interfaces to the mobile launch communication system in use at KSC. An experiment designed to verify the intelligibility advantage of the display used 130 different call signs taken from the communications protocol used at NASA KSC. A 6 to 7 dB intelligibility advantage was found when multiple channels were spatially displayed, compared to monaural listening. The findings suggest that the use of a spatial auditory display could enhance both occupational and operational safety and efficiency of NASA operations.

Informatics tools to improve clinical research study implementation.

PubMed

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.

[The choice of the type of design in the clinical investigation studies. Case and control studies].

PubMed

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.

Attrition Bias Related to Missing Outcome Data: A Longitudinal Simulation Study.

PubMed

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.

GLobal Integrated Design Environment

NASA Technical Reports Server (NTRS)

Kunkel, Matthew; McGuire, Melissa; Smith, David A.; Gefert, Leon P.

2011-01-01

The GLobal Integrated Design Environment (GLIDE) is a collaborative engineering application built to resolve the design session issues of real-time passing of data between multiple discipline experts in a collaborative environment. Utilizing Web protocols and multiple programming languages, GLIDE allows engineers to use the applications to which they are accustomed in this case, Excel to send and receive datasets via the Internet to a database-driven Web server. Traditionally, a collaborative design session consists of one or more engineers representing each discipline meeting together in a single location. The discipline leads exchange parameters and iterate through their respective processes to converge on an acceptable dataset. In cases in which the engineers are unable to meet, their parameters are passed via e-mail, telephone, facsimile, or even postal mail. The result of this slow process of data exchange would elongate a design session to weeks or even months. While the iterative process remains in place, software can now exchange parameters securely and efficiently, while at the same time allowing for much more information about a design session to be made available. GLIDE is written in a compilation of several programming languages, including REALbasic, PHP, and Microsoft Visual Basic. GLIDE client installers are available to download for both Microsoft Windows and Macintosh systems. The GLIDE client software is compatible with Microsoft Excel 2000 or later on Windows systems, and with Microsoft Excel X or later on Macintosh systems. GLIDE follows the Client-Server paradigm, transferring encrypted and compressed data via standard Web protocols. Currently, the engineers use Excel as a front end to the GLIDE Client, as many of their custom tools run in Excel.

Analyzing self-controlled case series data when case confirmation rates are estimated from an internal validation sample.

PubMed

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.

KALI - An environment for the programming and control of cooperative manipulators

NASA Technical Reports Server (NTRS)

Hayward, Vincent; Hayati, Samad

1988-01-01

A design description is given of a controller for cooperative robots. The background and motivation for multiple arm control are discussed. A set of programming primitives which permit a programmer to specify cooperative tasks are described. Motion primitives specify asynchronous motions, master/slave motions, and cooperative motions. In the context of cooperative robots, trajectory generation issues are discussed and the authors' implementation briefly described. The relations between programming and control in the case of multiple robots are examined. The allocation of various tasks among a multiprocessor computer is described.

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…

Playing Modeling Games in the Science Classroom: The Case for Disciplinary Integration

ERIC Educational Resources Information Center

Sengupta, Pratim; Clark, Doug

2016-01-01

The authors extend the theory of "disciplinary integration" of games for science education beyond the virtual world of games, and identify two key themes of a practice-based theoretical commitment to science learning: (1) materiality in the classroom, and (2) iterative design of multiple, complementary, symbolic inscriptions (e.g.,…

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…

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…

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…

The Entrepreneurship Bootcamp for Veterans' Families Program: Transformative Learning for Discontinuous Life Transition

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…

Coaching Teachers to Support Child Communication across Daily Routines in Early Head Start Classrooms

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…

Using Formative Student Feedback: A Continuous Quality Improvement Approach for Online Course Development

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…

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.…

Balancing Teacher and Student Roles in Elementary Classrooms: Preservice Elementary Teachers' Learning about the Inquiry Continuum

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…

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…

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…

76 FR 50484 - Draft Guidance for Industry, Clinical Investigators, and Food and Drug Administration Staff...

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...

Investing in the Improvement of Education: Lessons to be Learned from the National Writing Project

ERIC Educational Resources Information Center

St. John, Mark; Stokes, Laura

2008-01-01

This paper defines the concept of "improvement infrastructure" and "educational capital" for education, and it uses the case of the National Writing Project to develop an extended, data-based illustration of the design and generativeness of an improvement infrastructure. Since 1983 there have been multiple "waves" 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…

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…

A Case Study of Cognitive and Biophysical Models of Education as Linked to Anxiety and Obsessive Compulsive Disorders

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…

A Writing Intervention to Teach Simple Sentences and Descriptive Paragraphs to Adolescents with Writing Difficulties

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.…

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…

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.…

Investigating Coherence among Turkish Elementary Science Teachers' Teaching Belief Systems, Pedagogical Content Knowledge and Practice

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…

Factors Influencing Teacher Instructional Practice in Mathematics When Participating in Professional Development

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…

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…

A Multiple Case Study Based on Action-Oriented Sexuality Education: Perspectives of the Portuguese Teachers

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…

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…

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…

[GP medication prioritisation in older patients with multiple comorbidities recently discharged from hospital: a case-based bottom-up approach].

PubMed

Herrmann, M L H; von Waldegg, G H; Kip, M; Lehmann, B; Andrusch, S; Straub, H; Robra, B-P

2015-01-01

After the hospital discharge of older patients with multiple morbidities, GPs are often faced with the task of prioritising the patients' drug regimens so as to reduce the risk of overmedication. How do GPs prioritise such medications in multimorbid elderly patients at the transition between inpatient and home care? The experience by the GPs is documented in typical case vignettes. 44 GPs in Sachsen-Anhalt were recruited--they were engaged in focus group discussions and interviewed using semi-standardised questionnaires. Typical case vignettes were developed, relevant to the everyday care that elderly patients would typically receive from their GPs with respect to their drug optimisation. According to the results of the focus groups, the following issues affect GPs' decisions: drug and patient safety, their own competence in the health system, patient health literacy, evidence base, communication between secondary and primary care (and their respective influences on each other). When considering individual cases, patient safety, patient wishes, and quality of life were central. This is demonstrated by the drug dispositions of one exemplary case vignette. GPs do prioritise drug regimens with rational criteria. Initial problem delineation, process documentation and the design of a transferable product are interlinking steps in the development of case vignettes. Care issues of drug therapy in elderly patients with multiple morbidities should be investigated further with larger representative samples in order to clarify whether the criteria used here are applied contextually or consistently. Embedding case vignettes into further education concepts is also likely to be useful. © Georg Thieme Verlag KG Stuttgart · New York.

Report of Increasing Overdose Deaths that include Acetyl Fentanyl in Multiple Counties of the Southwestern Region of the Commonwealth of Pennsylvania in 2015-2016.

PubMed

Dwyer, Jessica B; Janssen, Jennifer; Luckasevic, Todd M; Williams, Karl E

2018-01-01

Acetyl fentanyl is a Schedule I controlled synthetic opioid that is becoming an increasingly detected "designer drug." Routine drug screening procedures in local forensic toxicology laboratories identified a total of 41 overdose deaths associated with acetyl fentanyl within multiple counties of the southwestern region of the state of Pennsylvania. The range, median, mean, and standard deviation of blood acetyl fentanyl concentrations for these 41 cases were 0.13-2100 ng/mL, 11 ng/mL, 169.3 ng/mL, and 405.3 ng/mL, respectively. Thirty-six individuals (88%) had a confirmed history of substance abuse, and all but one case (96%) were ruled multiple drug toxicities. This report characterizes this localized trend of overdose deaths associated with acetyl fentanyl and provides further evidence supporting an alarmingly concentrated opiate and opioid epidemic of both traditional and novel drugs within this region of the United States. © 2017 American Academy of Forensic Sciences.

Bayesian Estimation of Pneumonia Etiology: Epidemiologic Considerations and Applications to the Pneumonia Etiology Research for Child Health Study

PubMed Central

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

Habit Breaking Appliance for Multiple Corrections

PubMed Central

Abraham, Reji; Kamath, Geetha; Sodhi, Jasmeet Singh; Sodhi, Sonia; Rita, Chandki; Sai Kalyan, S.

2013-01-01

Tongue thrusting and thumb sucking are the most commonly seen oral habits which act as the major etiological factors in the development of dental malocclusion. This case report describes a fixed habit correcting appliance, Hybrid Habit Correcting Appliance (HHCA), designed to eliminate these habits. This hybrid appliance is effective in less compliant patients and if desired can be used along with the fixed orthodontic appliance. Its components can act as mechanical restrainers and muscle retraining devices. It is also effective in cases with mild posterior crossbites. PMID:24198976

The Validity of the Comparative Interrupted Time Series Design for Evaluating the Effect of School-Level Interventions.

PubMed

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.

Masked Visual Analysis: Minimizing Type I Error in Visually Guided Single-Case Design for Communication Disorders

PubMed Central

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

Masked Visual Analysis: Minimizing Type I Error in Visually Guided Single-Case Design for Communication Disorders.

PubMed

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.

Optical design of a Michelson wide-field multiple-aperture telescope

NASA Astrophysics Data System (ADS)

Cassaing, Frederic; Sorrente, Beatrice; Fleury, Bruno; Laubier, David

2004-02-01

Multiple-Aperture Optical Telescopes (MAOTs) are a promising solution for very high resolution imaging. In the Michelson configuration, the instrument is made of sub-telescopes distributed in the pupil and combined by a common telescope via folding periscopes. The phasing conditions of the sub-pupils lead to specific optical constraints in these subsystems. The amplitude of main contributors to the wavefront error (WFE) is given as a function of high level requirements (such as field or resolution) and free parameters, mainly the sub-telescope type, magnification and diameter. It is shown that for the periscopes, the field-to-resolution ratio is the main design driver and can lead to severe specifications. The effect of sub-telescopes aberrations on the global WFE can be minimized by reducing their diameter. An analytical tool for the MAOT design has been derived from this analysis, illustrated and validated in three different cases: LEO or GEO Earth observation and astronomy with extremely large telescopes. The last two cases show that a field larger than 10 000 resolution elements can be covered with a very simple MAOT based on Mersenne paraboloid-paraboloid sub-telescopes. Michelson MAOTs are thus a solution to be considered for high resolution wide-field imaging, from space or ground.

Structural Optimization for Reliability Using Nonlinear Goal Programming

NASA Technical Reports Server (NTRS)

El-Sayed, Mohamed E.

1999-01-01

This report details the development of a reliability based multi-objective design tool for solving structural optimization problems. Based on two different optimization techniques, namely sequential unconstrained minimization and nonlinear goal programming, the developed design method has the capability to take into account the effects of variability on the proposed design through a user specified reliability design criterion. In its sequential unconstrained minimization mode, the developed design tool uses a composite objective function, in conjunction with weight ordered design objectives, in order to take into account conflicting and multiple design criteria. Multiple design criteria of interest including structural weight, load induced stress and deflection, and mechanical reliability. The nonlinear goal programming mode, on the other hand, provides for a design method that eliminates the difficulty of having to define an objective function and constraints, while at the same time has the capability of handling rank ordered design objectives or goals. For simulation purposes the design of a pressure vessel cover plate was undertaken as a test bed for the newly developed design tool. The formulation of this structural optimization problem into sequential unconstrained minimization and goal programming form is presented. The resulting optimization problem was solved using: (i) the linear extended interior penalty function method algorithm; and (ii) Powell's conjugate directions method. Both single and multi-objective numerical test cases are included demonstrating the design tool's capabilities as it applies to this design problem.

Calibrating the Medical Council of Canada's Qualifying Examination Part I using an integrated item response theory framework: a comparison of models and designs.

PubMed

De Champlain, Andre F; Boulais, Andre-Philippe; Dallas, Andrew

2016-01-01

The aim of this research was to compare different methods of calibrating multiple choice question (MCQ) and clinical decision making (CDM) components for the Medical Council of Canada's Qualifying Examination Part I (MCCQEI) based on item response theory. Our data consisted of test results from 8,213 first time applicants to MCCQEI in spring and fall 2010 and 2011 test administrations. The data set contained several thousand multiple choice items and several hundred CDM cases. Four dichotomous calibrations were run using BILOG-MG 3.0. All 3 mixed item format (dichotomous MCQ responses and polytomous CDM case scores) calibrations were conducted using PARSCALE 4. The 2-PL model had identical numbers of items with chi-square values at or below a Type I error rate of 0.01 (83/3,499 or 0.02). In all 3 polytomous models, whether the MCQs were either anchored or concurrently run with the CDM cases, results suggest very poor fit. All IRT abilities estimated from dichotomous calibration designs correlated very highly with each other. IRT-based pass-fail rates were extremely similar, not only across calibration designs and methods, but also with regard to the actual reported decision to candidates. The largest difference noted in pass rates was 4.78%, which occurred between the mixed format concurrent 2-PL graded response model (pass rate= 80.43%) and the dichotomous anchored 1-PL calibrations (pass rate= 85.21%). Simpler calibration designs with dichotomized items should be implemented. The dichotomous calibrations provided better fit of the item response matrix than more complex, polytomous calibrations.

Case-based ethics instruction: the influence of contextual and individual factors in case content on ethical decision-making.

PubMed

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.

Fly-By-Light/Power-By-Wire Fault-Tolerant Fiber-Optic Backplane

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R.

2002-01-01

The design and development of a fault-tolerant fiber-optic backplane to demonstrate feasibility of such architecture is presented. The simulation results of test cases on the backplane in the advent of induced faults are presented, and the fault recovery capability of the architecture is demonstrated. The architecture was designed, developed, and implemented using the Very High Speed Integrated Circuits (VHSIC) Hardware Description Language (VHDL). The architecture was synthesized and implemented in hardware using Field Programmable Gate Arrays (FPGA) on multiple prototype boards.

Continuing Experiments on the Receptivity of Transient Disturbances to Surface Roughness and Freestream Turbulence

DTIC Science & Technology

2008-09-28

rotating the spindle of the angle controller with a precision of 0.2°. The multiple-hotwire holder is designed to carry four hotwires. One hotwire is a...section and a maximum operating speed of 25 m/s. The tunnel’s design follows the recommendations of Reshotko et al. (1997) for flow quality. Operating at...This sting assembly includes a shaft that rotates in a streamlined casing and allows angular calibration of slanted hotwires. Outside the test

Climate Change Professional Development: Design, Implementation, and Initial Outcomes on Teacher Learning, Practice, and Student Beliefs

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.

Logistics system design for biomass-to-bioenergy industry with multiple types of feedstocks.

PubMed

Zhu, Xiaoyan; Yao, Qingzhu

2011-12-01

It is technologically possible for a biorefinery to use a variety of biomass as feedstock including native perennial grasses (e.g., switchgrass) and agricultural residues (e.g., corn stalk and wheat straw). Incorporating the distinct characteristics of various types of biomass feedstocks and taking into account their interaction in supplying the bioenergy production, this paper proposed a multi-commodity network flow model to design the logistics system for a multiple-feedstock biomass-to-bioenergy industry. The model was formulated as a mixed integer linear programming, determining the locations of warehouses, the size of harvesting team, the types and amounts of biomass harvested/purchased, stored, and processed in each month, the transportation of biomass in the system, and so on. This paper demonstrated the advantages of using multiple types of biomass feedstocks by comparing with the case of using a single feedstock (switchgrass) and analyzed the relationship of the supply capacity of biomass feedstocks to the output and cost of biofuel. Copyright © 2011 Elsevier Ltd. All rights reserved.

Designing and implementing an electronic dashboard for disease outbreaks response - Case study of the 2013-2014 Somalia Polio outbreak response dashboard

PubMed Central

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

Designing and implementing an electronic dashboard for disease outbreaks response - Case study of the 2013-2014 Somalia Polio outbreak response dashboard.

PubMed

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.

One-shot estimate of MRMC variance: AUC.

PubMed

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.

Exploring interprofessional, interagency multimorbidity care: case study based observational research

PubMed Central

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

Feasibility and potential effectiveness of a non-pharmacological multidisciplinary care programme for persons with generalised osteoarthritis: a randomised, multiple-baseline single-case study

PubMed Central

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

Full-order optimal compensators for flow control: the multiple inputs case

NASA Astrophysics Data System (ADS)

Semeraro, Onofrio; Pralits, Jan O.

2018-03-01

Flow control has been the subject of numerous experimental and theoretical works. We analyze full-order, optimal controllers for large dynamical systems in the presence of multiple actuators and sensors. The full-order controllers do not require any preliminary model reduction or low-order approximation: this feature allows us to assess the optimal performance of an actuated flow without relying on any estimation process or further hypothesis on the disturbances. We start from the original technique proposed by Bewley et al. (Meccanica 51(12):2997-3014, 2016. https://doi.org/10.1007/s11012-016-0547-3), the adjoint of the direct-adjoint (ADA) algorithm. The algorithm is iterative and allows bypassing the solution of the algebraic Riccati equation associated with the optimal control problem, typically infeasible for large systems. In this numerical work, we extend the ADA iteration into a more general framework that includes the design of controllers with multiple, coupled inputs and robust controllers (H_{∞} methods). First, we demonstrate our results by showing the analytical equivalence between the full Riccati solutions and the ADA approximations in the multiple inputs case. In the second part of the article, we analyze the performance of the algorithm in terms of convergence of the solution, by comparing it with analogous techniques. We find an excellent scalability with the number of inputs (actuators), making the method a viable way for full-order control design in complex settings. Finally, the applicability of the algorithm to fluid mechanics problems is shown using the linearized Kuramoto-Sivashinsky equation and the Kármán vortex street past a two-dimensional cylinder.

[Peculiarities of upper urinary tract drainage during surgical treatment of staghorn and multiple nephrolithiasis].

PubMed

Imamverdiev, S B; Talybov, T A; Mamedov, R N

2014-01-01

This work was designed to evaluate methods of kidney drainage used in the surgical treatment of 250 patients with staghorn and multiple nephrolithiasis (SMN). All of them underwent open surgery that was followed by drainage of the upper urinary tract in 192 patients. Internal stenting was used in 111 cases, pyelostomy in 28, nephrostomy in 47, and internal stenting with nephrostoma in 6 cases. 91 and 20 patients had a stent inserted into the upper urinary tract in a retrograde and antegrade manner respectively. Retrograde stenting was bilateral in 14 and unilateral in 66 cases. 85% of the cases with ureter stents were followed up as outpatients for 4-5 weeks and only 10% for 6-7 weeks. Forty and ten patients with stents presented with marked dysuria and hematuria respectively. On the whole, combined antibacterial treatment with drainage of the upper urinary tract significantly improved long-term results of SMN treatment. It is concluded that nephrostomy and pyelostomy should be performed on days 14-18 and 10-12 respectively whereas the stent needs to be removed between weeks 2 and 8 after surgery.

Launch Vehicle Propulsion Design with Multiple Selection Criteria

NASA Technical Reports Server (NTRS)

Shelton, Joey D.; Frederick, Robert A.; Wilhite, Alan W.

2005-01-01

The approach and techniques described herein define an optimization and evaluation approach for a liquid hydrogen/liquid oxygen single-stage-to-orbit system. The method uses Monte Carlo simulations, genetic algorithm solvers, a propulsion thermo-chemical code, power series regression curves for historical data, and statistical models in order to optimize a vehicle system. The system, including parameters for engine chamber pressure, area ratio, and oxidizer/fuel ratio, was modeled and optimized to determine the best design for seven separate design weight and cost cases by varying design and technology parameters. Significant model results show that a 53% increase in Design, Development, Test and Evaluation cost results in a 67% reduction in Gross Liftoff Weight. Other key findings show the sensitivity of propulsion parameters, technology factors, and cost factors and how these parameters differ when cost and weight are optimized separately. Each of the three key propulsion parameters; chamber pressure, area ratio, and oxidizer/fuel ratio, are optimized in the seven design cases and results are plotted to show impacts to engine mass and overall vehicle mass.

Development of a State Machine Sequencer for the Keck Interferometer: Evolution, Development and Lessons Learned using a CASE Tool Approach

NASA Technical Reports Server (NTRS)

Rede, Leonard J.; Booth, Andrew; Hsieh, Jonathon; Summer, Kellee

2004-01-01

This paper presents a discussion of the evolution of a sequencer from a simple EPICS (Experimental Physics and Industrial Control System) based sequencer into a complex implementation designed utilizing UML (Unified Modeling Language) methodologies and a CASE (Computer Aided Software Engineering) tool approach. The main purpose of the sequencer (called the IF Sequencer) is to provide overall control of the Keck Interferometer to enable science operations be carried out by a single operator (and/or observer). The interferometer links the two 10m telescopes of the W. M. Keck Observatory at Mauna Kea, Hawaii. The IF Sequencer is a high-level, multi-threaded, Hare1 finite state machine, software program designed to orchestrate several lower-level hardware and software hard real time subsystems that must perform their work in a specific and sequential order. The sequencing need not be done in hard real-time. Each state machine thread commands either a high-speed real-time multiple mode embedded controller via CORB A, or slower controllers via EPICS Channel Access interfaces. The overall operation of the system is simplified by the automation. The UML is discussed and our use of it to implement the sequencer is presented. The decision to use the Rhapsody product as our CASE tool is explained and reflected upon. Most importantly, a section on lessons learned is presented and the difficulty of integrating CASE tool automatically generated C++ code into a large control system consisting of multiple infrastructures is presented.

Development of a state machine sequencer for the Keck Interferometer: evolution, development, and lessons learned using a CASE tool approach

NASA Astrophysics Data System (ADS)

Reder, Leonard J.; Booth, Andrew; Hsieh, Jonathan; Summers, Kellee R.

2004-09-01

This paper presents a discussion of the evolution of a sequencer from a simple Experimental Physics and Industrial Control System (EPICS) based sequencer into a complex implementation designed utilizing UML (Unified Modeling Language) methodologies and a Computer Aided Software Engineering (CASE) tool approach. The main purpose of the Interferometer Sequencer (called the IF Sequencer) is to provide overall control of the Keck Interferometer to enable science operations to be carried out by a single operator (and/or observer). The interferometer links the two 10m telescopes of the W. M. Keck Observatory at Mauna Kea, Hawaii. The IF Sequencer is a high-level, multi-threaded, Harel finite state machine software program designed to orchestrate several lower-level hardware and software hard real-time subsystems that must perform their work in a specific and sequential order. The sequencing need not be done in hard real-time. Each state machine thread commands either a high-speed real-time multiple mode embedded controller via CORBA, or slower controllers via EPICS Channel Access interfaces. The overall operation of the system is simplified by the automation. The UML is discussed and our use of it to implement the sequencer is presented. The decision to use the Rhapsody product as our CASE tool is explained and reflected upon. Most importantly, a section on lessons learned is presented and the difficulty of integrating CASE tool automatically generated C++ code into a large control system consisting of multiple infrastructures is presented.

Electrical Engineering and Nontechnical Design Variables of Multiple Inductive Loop Systems for Auditoriums

ERIC Educational Resources Information Center

Alterovitz, Gil

2004-01-01

This research analyzed both engineering and nontechnical issues involved in the use of Induction Loop Amplification (ILA) devices in auditoriums or large gathering places for hard-of-hearing individuals. A variety of parameters need to be taken into account to determine an optimal shape/configuration for the ILA device. In many cases, an optimal…

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…

Exploring Elementary Teachers' Perceptions about the Developmental Appropriateness and Importance of Nature of Science Aspects

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…

Concept-Guided Development of ICT Use in "Traditional" and "Innovative" Primary Schools: What Types of ICT Use Do Schools Develop?

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…

Randomization-Based Inference about Latent Variables from Complex Samples: The Case of Two-Stage Sampling

ERIC Educational Resources Information Center

Li, Tiandong

2012-01-01

In large-scale assessments, such as the National Assessment of Educational Progress (NAEP), plausible values based on Multiple Imputations (MI) have been used to estimate population characteristics for latent constructs under complex sample designs. Mislevy (1991) derived a closed-form analytic solution for a fixed-effect model in creating…

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…

eCoaching across Routines to Enhance Teachers' Use of Modeling

ERIC Educational Resources Information Center

Coogle, Christan Grygas; Rahn, Naomi L.; Ottley, Jennifer Riggie; Storie, Sloan

2016-01-01

The purpose of this research was to determine the impact of eCoaching on two special education teachers' use of modeling strategies across child-led, teacher-led, and mealtime routines. A multiple-probe, single-case design was used to determine the effects of eCoaching on teachers' use of three modeling strategies. Each of the three strategies…

Bug-in-Ear eCoaching: Impacts on Novice Early Childhood Special Education Teachers

ERIC Educational Resources Information Center

Grygas Coogle, Christan; Ottley, Jennifer R.; Rahn, Naomi L.; Storie, Sloan

2018-01-01

A multiple-probe, single-case design was used to determine the effects of bug-in-ear eCoaching on teachers' use of two targeted naturalistic communication strategies and focus children's responses to these strategies. Results indicated that bug-in-ear eCoaching enhanced teachers' use of communication strategies and the appropriate responses of…

Supporting Early Childhood Educators' Use of Embedded Communication Strategies by Providing Feedback via Bug-in-Ear Technology

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.…

Video-Based Intervention in Teaching Fraction Problem-Solving to Students with Autism Spectrum Disorder

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…

Learning with Technology: Video Modeling with Concrete-Representational-Abstract Sequencing for Students with Autism Spectrum Disorder

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…

Leadership Behaviour in High-Performing Government Boys Secondary Schools in Quetta: A Grounded Theory Analysis

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…

Understanding the Technological, Pedagogical, and Mathematical Issues That Emerge as Secondary Mathematics Teachers Design Lessons That Integrate Technology

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…

Efficacy of Cognitive-Behavioral Therapy for Comorbid Panic Disorder with Agoraphobia and Generalized Anxiety Disorder

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…

Cognitive-Behavioral Therapy for Comorbid Generalized Anxiety Disorder and Panic Disorder with Agoraphobia

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…

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…

Formative Assessment Using Direct Behavior Ratings: Evaluating Intervention Effects of Daily Behavior Report Cards

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…

Investigating Plane Geometry Problem-Solving Strategies of Prospective Mathematics Teachers in Technology and Paper-and-Pencil Environments

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…

Investigating Multicultural Education Phenomena in Minority and Public High Schools in Turkey: A Multiple Case Study

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…

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…

The Perceived Effect of Hidden Costs on the Operational Management of Information Technology Outsourcing: A Qualitative Study

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…

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…

A generalized least squares regression approach for computing effect sizes in single-case research: application examples.

PubMed

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.

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.

Effectiveness of cognitive orientation to (daily) occupational performance (CO-OP) on children with cerebral palsy: A mixed design.

PubMed

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.

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.

Mission Design and Simulation Considerations for ADReS-A

NASA Astrophysics Data System (ADS)

Peters, S.; Förstner, R.; Fiedler, H.

2016-09-01

Space debris in general has become a major problem for modern space activities. Guidelines to mitigate the threat have been recommended, better prediction models are developed and an advanced observation of objects orbiting Earth is in progress. And still - without the implementation of active debris removal (ADR), the number of debris in space will exponentially increase. To support the ongoing research on ADR-missions, this paper presents the updated mission design of ADReS-A (Autonomous Debris Removal Satellite - #A) - one possible concept for the multiple active removal of large debris in Low Earth orbit, in this case especially of rocket bodies of the SL-8-type. ADReS-A as chaser satellite is supported by at least 5 de-orbit kits, allowing for the same number of targets to be removed. While ADReS-A is conceived for handling of the target, the kit's task is the controlled re-entry of the designated rocket body. The presented mission design forms the basis for the simulation environment in progress. The simulation shall serve as testbed to test multiple scenarios in terms of approach and abort optimization or different tumbling modes of the target. The ultimate goal is the test of autonomous behaviors of the spacecraft in case of unforeseen failures during the approach phase. Considerations to create a simulation for the described mission are presented and discussed. A first visualization of pre-calculated aboard trajectories can be found at the end of this paper.

Methods to control for unmeasured confounding in pharmacoepidemiology: an overview.

PubMed

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.

Optimal Policy of Cross-Layer Design for Channel Access and Transmission Rate Adaptation in Cognitive Radio Networks

NASA Astrophysics Data System (ADS)

He, Hao; Wang, Jun; Zhu, Jiang; Li, Shaoqian

2010-12-01

In this paper, we investigate the cross-layer design of joint channel access and transmission rate adaptation in CR networks with multiple channels for both centralized and decentralized cases. Our target is to maximize the throughput of CR network under transmission power constraint by taking spectrum sensing errors into account. In centralized case, this problem is formulated as a special constrained Markov decision process (CMDP), which can be solved by standard linear programming (LP) method. As the complexity of finding the optimal policy by LP increases exponentially with the size of action space and state space, we further apply action set reduction and state aggregation to reduce the complexity without loss of optimality. Meanwhile, for the convenience of implementation, we also consider the pure policy design and analyze the corresponding characteristics. In decentralized case, where only local information is available and there is no coordination among the CR users, we prove the existence of the constrained Nash equilibrium and obtain the optimal decentralized policy. Finally, in the case that the traffic load parameters of the licensed users are unknown for the CR users, we propose two methods to estimate the parameters for two different cases. Numerical results validate the theoretic analysis.

Object Oriented Modeling and Design

NASA Technical Reports Server (NTRS)

Shaykhian, Gholam Ali

2007-01-01

The Object Oriented Modeling and Design seminar is intended for software professionals and students, it covers the concepts and a language-independent graphical notation that can be used to analyze problem requirements, and design a solution to the problem. The seminar discusses the three kinds of object-oriented models class, state, and interaction. The class model represents the static structure of a system, the state model describes the aspects of a system that change over time as well as control behavior and the interaction model describes how objects collaborate to achieve overall results. Existing knowledge of object oriented programming may benefit the learning of modeling and good design. Specific expectations are: Create a class model, Read, recognize, and describe a class model, Describe association and link, Show abstract classes used with multiple inheritance, Explain metadata, reification and constraints, Group classes into a package, Read, recognize, and describe a state model, Explain states and transitions, Read, recognize, and describe interaction model, Explain Use cases and use case relationships, Show concurrency in activity diagram, Object interactions in sequence diagram.

Information architecture considerations in designing a comprehensive tuberculosis enterprise system in Western Kenya.

PubMed

Gichoya, Judy; Pearce, Chris; Wickramasinghe, Nilmini

2013-01-01

Kenya ranks among the twenty-two countries that collectively contribute about 80% of the world's Tuberculosis cases; with a 50-200 fold increased risk of tuberculosis in HIV infected persons versus non-HIV hosts. Contemporaneously, there is an increase in mobile penetration and its use to support healthcare throughout Africa. Many are skeptical that such m-health solutions are unsustainable and not scalable. We seek to design a scalable, pervasive m-health solution for Tuberculosis care to become a use case for sustainable and scalable health IT in limited resource settings. We combine agile design principles and user-centered design to develop the architecture needed for this initiative. Furthermore, the architecture runs on multiple devices integrated to deliver functionality critical for successful Health IT implementation in limited resource settings. It is anticipated that once fully implemented, the proposed m-health solution will facilitate superior monitoring and management of Tuberculosis and thereby reduce the alarming statistic regarding this disease in this region.

Simulation of Synthetic Jets in Quiescent Air Using Unsteady Reynolds Averaged Navier-Stokes Equations

NASA Technical Reports Server (NTRS)

Vatsa, Veer N.; Turkel, Eli

2006-01-01

We apply an unsteady Reynolds-averaged Navier-Stokes (URANS) solver for the simulation of a synthetic jet created by a single diaphragm piezoelectric actuator in quiescent air. This configuration was designated as Case 1 for the CFDVAL2004 workshop held at Williamsburg, Virginia, in March 2004. Time-averaged and instantaneous data for this case were obtained at NASA Langley Research Center, using multiple measurement techniques. Computational results for this case using one-equation Spalart-Allmaras and two-equation Menter's turbulence models are presented along with the experimental data. The effect of grid refinement, preconditioning and time-step variation are also examined in this paper.

A Case of Prolonged Delayed Postdural Puncture Headache in a Patient with Multiple Sclerosis Exacerbated by Air Travel

PubMed Central

Porhomayon, Jahan; Zadeii, Gino; Yarahamadi, Alireza; Nader, Nader D.

2013-01-01

The developments of new spinal needles and needle tip designs have reduced the incidence of postdural puncture headache (PDPH). Although it is clear that reducing the loss of CSF leak from dural puncture reduces the headache, there are areas regarding the pathogenesis, treatment, and prevention of PDPH that remain controversial. Air travel by itself may impose physiological alteration in central nervous system that may be detrimental to patients with PDPH. This case report highlights a case of a young female patient who suffered from a severe incapacitating PDPH headache during high-altitude flight with a commercial jet. PMID:23401803

Using multiple metaphors and multimodalities as a semiotic resource when teaching year 2 students computational strategies

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.

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.

Documentation for the machine-readable version of the general catalogue of 33342 stars for the epoch 1950 (Boss 1937)

NASA Technical Reports Server (NTRS)

Roman, N. G.; Warren, W. H., Jr.

1983-01-01

A revised and corrected version of the machine-readable catalog has been prepared. Cross identifications of the GC stars to the HD and DM catalogs have been replaced by data from the new SAO-HD-GC-DM Cross Index (Roman, Warren and Schofield 1983), including component identifications for multiple SAO entries having identical DM numbers in the SAO Catalog, supplemental Bonner Durchmusterung stars (lower case letter designations) and codes for multiple HD stars. Additional individual corrections have been incorporated based upon errors found during analyses of other catalogs.

The weighted priors approach for combining expert opinions in logistic regression experiments

DOE PAGES

Quinlan, Kevin R.; Anderson-Cook, Christine M.; Myers, Kary L.

2017-04-24

When modeling the reliability of a system or component, it is not uncommon for more than one expert to provide very different prior estimates of the expected reliability as a function of an explanatory variable such as age or temperature. Our goal in this paper is to incorporate all information from the experts when choosing a design about which units to test. Bayesian design of experiments has been shown to be very successful for generalized linear models, including logistic regression models. We use this approach to develop methodology for the case where there are several potentially non-overlapping priors under consideration.more » While multiple priors have been used for analysis in the past, they have never been used in a design context. The Weighted Priors method performs well for a broad range of true underlying model parameter choices and is more robust when compared to other reasonable design choices. Finally, we illustrate the method through multiple scenarios and a motivating example. Additional figures for this article are available in the online supplementary information.« less

The weighted priors approach for combining expert opinions in logistic regression experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quinlan, Kevin R.; Anderson-Cook, Christine M.; Myers, Kary L.

When modeling the reliability of a system or component, it is not uncommon for more than one expert to provide very different prior estimates of the expected reliability as a function of an explanatory variable such as age or temperature. Our goal in this paper is to incorporate all information from the experts when choosing a design about which units to test. Bayesian design of experiments has been shown to be very successful for generalized linear models, including logistic regression models. We use this approach to develop methodology for the case where there are several potentially non-overlapping priors under consideration.more » While multiple priors have been used for analysis in the past, they have never been used in a design context. The Weighted Priors method performs well for a broad range of true underlying model parameter choices and is more robust when compared to other reasonable design choices. Finally, we illustrate the method through multiple scenarios and a motivating example. Additional figures for this article are available in the online supplementary information.« less

Towards Robust Designs Via Multiple-Objective Optimization Methods

NASA Technical Reports Server (NTRS)

Man Mohan, Rai

2006-01-01

Fabricating and operating complex systems involves dealing with uncertainty in the relevant variables. In the case of aircraft, flow conditions are subject to change during operation. Efficiency and engine noise may be different from the expected values because of manufacturing tolerances and normal wear and tear. Engine components may have a shorter life than expected because of manufacturing tolerances. In spite of the important effect of operating- and manufacturing-uncertainty on the performance and expected life of the component or system, traditional aerodynamic shape optimization has focused on obtaining the best design given a set of deterministic flow conditions. Clearly it is important to both maintain near-optimal performance levels at off-design operating conditions, and, ensure that performance does not degrade appreciably when the component shape differs from the optimal shape due to manufacturing tolerances and normal wear and tear. These requirements naturally lead to the idea of robust optimal design wherein the concept of robustness to various perturbations is built into the design optimization procedure. The basic ideas involved in robust optimal design will be included in this lecture. The imposition of the additional requirement of robustness results in a multiple-objective optimization problem requiring appropriate solution procedures. Typically the costs associated with multiple-objective optimization are substantial. Therefore efficient multiple-objective optimization procedures are crucial to the rapid deployment of the principles of robust design in industry. Hence the companion set of lecture notes (Single- and Multiple-Objective Optimization with Differential Evolution and Neural Networks ) deals with methodology for solving multiple-objective Optimization problems efficiently, reliably and with little user intervention. Applications of the methodologies presented in the companion lecture to robust design will be included here. The evolutionary method (DE) is first used to solve a relatively difficult problem in extended surface heat transfer wherein optimal fin geometries are obtained for different safe operating base temperatures. The objective of maximizing the safe operating base temperature range is in direct conflict with the objective of maximizing fin heat transfer. This problem is a good example of achieving robustness in the context of changing operating conditions. The evolutionary method is then used to design a turbine airfoil; the two objectives being reduced sensitivity of the pressure distribution to small changes in the airfoil shape and the maximization of the trailing edge wedge angle with the consequent increase in airfoil thickness and strength. This is a relevant example of achieving robustness to manufacturing tolerances and wear and tear in the presence of other objectives.

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.

Jump state estimation with multiple sensors with packet dropping and delaying channels

NASA Astrophysics Data System (ADS)

Dolz, Daniel; Peñarrocha, Ignacio; Sanchis, Roberto

2016-03-01

This work addresses the design of a state observer for systems whose outputs are measured through a communication network. The measurements from each sensor node are assumed to arrive randomly, scarcely and with a time-varying delay. The proposed model of the plant and the network measurement scenarios cover the cases of multiple sensors, out-of-sequence measurements, buffered measurements on a single packet and multirate sensor measurements. A jump observer is proposed that selects a different gain depending on the number of periods elapsed between successfully received measurements and on the available data. A finite set of gains is pre-calculated offline with a tractable optimisation problem, where the complexity of the observer implementation is a design parameter. The computational cost of the observer implementation is much lower than in the Kalman filter, whilst the performance is similar. Several examples illustrate the observer design for different measurement scenarios and observer complexity and show the achievable performance.

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.

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.

The role of economic evaluation in the decision-making process of family physicians: design and methods of a qualitative embedded multiple-case study

PubMed Central

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

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.

The emergence of designed multiple ligands for neurodegenerative disorders.

PubMed

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.

A new piezoelectric energy harvesting design concept: multimodal energy harvesting skin.

PubMed

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.

Integrated layout based Monte-Carlo simulation for design arc optimization

NASA Astrophysics Data System (ADS)

Shao, Dongbing; Clevenger, Larry; Zhuang, Lei; Liebmann, Lars; Wong, Robert; Culp, James

2016-03-01

Design rules are created considering a wafer fail mechanism with the relevant design levels under various design cases, and the values are set to cover the worst scenario. Because of the simplification and generalization, design rule hinders, rather than helps, dense device scaling. As an example, SRAM designs always need extensive ground rule waivers. Furthermore, dense design also often involves "design arc", a collection of design rules, the sum of which equals critical pitch defined by technology. In design arc, a single rule change can lead to chain reaction of other rule violations. In this talk we present a methodology using Layout Based Monte-Carlo Simulation (LBMCS) with integrated multiple ground rule checks. We apply this methodology on SRAM word line contact, and the result is a layout that has balanced wafer fail risks based on Process Assumptions (PAs). This work was performed at the IBM Microelectronics Div, Semiconductor Research and Development Center, Hopewell Junction, NY 12533

Nonparametric Multiple Imputation for Questionnaires with Individual Skip Patterns and Constraints: The Case of Income Imputation in The National Educational Panel Study

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…

The Effects of a Peer-Mediated Reading Intervention on Juvenile Offenders' Main Idea Statements about Informational Text

ERIC Educational Resources Information Center

Wexler, Jade; Reed, Deborah K.; Barton, Erin E.; Mitchell, Marisa; Clancy, Erin

2018-01-01

Many youth in the juvenile justice system with or at risk for emotional and behavioral disorders struggle with reading. A multiple-baseline-across-participants single-case research design was used to examine the relationship between a supplemental peer-mediated reading intervention and juvenile offenders' generation of main idea statements about…

The Effects of Fading a Strategic Self-Monitoring Intervention on Students' Academic Engagement, Accuracy, and Productivity

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…

Effectiveness of Video Self-Modeling to Promote Social Initiations by 3-Year-Olds with Autism Spectrum Disorders

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…

Interdyad Differences in Early Mother-Infant Face-to-Face Communication: Real-Time Dynamics and Developmental Pathways

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…

Conjoint Analysis: A Preference-Based Approach for the Accounting of Multiple Benefits in Southern Forest Management

Treesearch

F. Christian Zinkhan; Thomas P. Holmes; D. Evan Mercer

1997-01-01

Conjoint analysis, which enables a manager to measure the relative importance of a forest's multidimensional attributes, is critically reviewed and assessed. Special attention is given to the feasibility of using conjoint analysis for measuring the utility of market and nonmarket outputs from southern forests. Also, an application to a case of designing a nature...

Planned diversity: The case for a system with several types of wilderness

Treesearch

David N. Cole

2011-01-01

Although the U.S. Wilderness Act of 1964 legally designated only one type of wilderness, the full array of wilderness values might be better protected by setting aside several important and different types of wilderness. Wilderness serves many different needs, having multiple and varied values and purposes (Cordell et al. 2005). Although many assume that these values...

Toward the Development of Integrative Risk-Adjusted Measures of Quality Using Large Clinical Data Bases: The Case of Anesthesia Services.

ERIC Educational Resources Information Center

Fleming, Steven T.

1992-01-01

The concept of risk-adjusted measures of quality is discussed, and a methodology is proposed for risk-adjusting and integrating multiple adverse outcomes of anesthesia services into measures for quality assurance and quality improvement programs. Although designed for a new anesthesiology database, the methods should apply to other health…

eCoaching across Routines to Enhance Teachers' Use of Modeling

ERIC Educational Resources Information Center

Coogle, Christan Grygas; Rahn, Naomi L.; Ottley, Jennifer Riggie; Storie, Sloan

2016-01-01

The purpose of this research was to determine the impact of eCoaching on two special education teachers' use of modeling strategies across child-led, teacher-led, and mealtime routines. A multiple-probe, single-case design was used to determine the effects of eCoaching on teachers' use of three modeling strategies. Each of the three strategies was…

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…

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…

"More Confident Going into College": Lessons Learned from Multiple Stakeholders in a New Blended Learning Initiative

ERIC Educational Resources Information Center

Whiteside, Aimee L.; Garrett Dikkers, Amy; Lewis, Somer

2016-01-01

This article examined a blended learning initiative in a large suburban high school in the Midwestern region of the United States. It employed a single-case exploratory design approach to learn about the experience of administrators, teachers, students, and parents. Using Zimmerman's Self-Regulated Learning (SRL) Theory as a guiding framework,…

The Role of the Teaching Experiment: Students' Construction of Transformations in a Multiple Representational Environment.

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…

Quality of Diagnosis and Treatment Plans after Using the "Diagnostic Guideline for Anxiety and Challenging Behaviours" in People with Intellectual Disabilities: A Comparative Multiple Case Study Design

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…

Self-Administered Cued Naming Therapy: A Single-Participant Investigation of a Computer-Based Therapy Program Replicated in Four Cases

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…

Kenya's Constituency Development Fund, Free Secondary Education Policy, and Access to Secondary Education

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…

An Instrument to Predict Job Performance of Home Health Aides--Testing the Reliability and Validity.

ERIC Educational Resources Information Center

Sturges, Jack; Quina, Patricia

The development of four paper-and-pencil tests, useful in assessing the effectiveness of inservice training provided to either nurses aides or home health aides, was described. These tests were designed for utilization in employment selection and case assignment. Two tests of 37 multiple-choice items and two tests of 10 matching items were…

Relationships between undergraduates' argumentation skills, conceptual quality of problem solutions, and problem solving strategies in introductory physics

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.

Imagery Rescripting for Body Dysmorphic Disorder: A Multiple-Baseline Single-Case Experimental Design.

PubMed

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.

Refining Inquiry with Multi-Form Assessment: Formative and summative assessment functions for flexible inquiry

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.

Tangled paths: Three experienced teachers' growth in understanding during an extended science community of practice professional development effort

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.

Two cases of multiple ossifying fibromas in the jaws

PubMed Central

2014-01-01

Background The clinicopathologic characteristics of multiple ossifying fibroma (OF) are unclear due to the condition’s rarity, making diagnosis challenging. Sporadic multiple OFs must be distinguished from hyperparathyroidism-jaw tumour syndrome (HPT-JT) related OF and other fibro-osseous lesions. Methods Multiple OF cases were identified from ossifying fibroma cases. Clinical data including age, sex, anatomic site, radiographic features, clinical impression, treatment and available follow-up data as well as serum calcium, phosphorus, and parathyroid hormone (PTH) were recorded. GNAS and HRPT2 genetic mutations were examined in the two present cases. Case reports of sporadic multiple ossifying fibroma and HPT-JT-related OF were also reviewed. Results The two present cases were confirmed as sporadic multiple OF, with no genetic GNAS and HRPT2 mutations found. The incidence of sporadic multiple ossifying fibroma was 2.0% (2/102). The total 18 sporadic multiform OF cases were characterized as followed: 13 (72.2%) female; 5 (27.8%) male; mean age 28.6 years; 2/16 (11.1%) cases only in the mandible; 4/18 (22.2%) cases only in the maxilla; and 12/18 (66.7%) cases in both the maxilla and mandible. Radiographically, the lesions were radiolucent in 5/18 (27.8%) cases and mixed density in 13/18 (72.2%) cases. Along with 24 cases of HPT-JT related OF were reviewed, sixteen (66.7%) patients were diagnosed with a single lesion, and 8 patients (33.3%) were diagnosed with multiple jaw lesions. Conclusions Sporadic multiple OFs are very rare, but must be distinguished from HPT-JT related OF. We strongly recommend that patients diagnosed with multiple ossifying fibromas receive serum PTH testing and mutation screening of HRPT2. Virtual slides http://www.diagnosticpathology.diagnomx.eu/vs/1194507146115753 PMID:24678936

A Multiple-Sequence Variant of the Multiple-Baseline Design: A Strategy for Analysis of Sequence Effects and Treatment Comparison.

ERIC Educational Resources Information Center

Noell, George H.; Gresham, Frank M.

2001-01-01

Describes design logic and potential uses of a variant of the multiple-baseline design. The multiple-baseline multiple-sequence (MBL-MS) consists of multiple-baseline designs that are interlaced with one another and include all possible sequences of treatments. The MBL-MS design appears to be primarily useful for comparison of treatments taking…

Work-Related Burn Injuries Hospitalized in US Burn Centers: 2002 to 2011.

PubMed

Huang, Zhenna; Friedman, Lee S

2017-03-01

To develop a comprehensive definition to identify work-related burns in the National Burn Repository (NBR) based on multiple fields and describes injuries by occupation. The NBR, which is an inpatient dataset, was used to compare type and severity of burn injuries by occupation. Using the definition developed for this analysis, 22,969 burn injuries were identified as work-related. In contrast, the single work-related field intended to capture occupational injuries only captured 4696 cases. The highest numbers of burns were observed in construction/extraction, food preparation, and durable goods production occupations. Occupations with a mean total body surface area (TBSA) burned greater than 10% include transportation and material-moving, architecture and engineering, and arts/design/entertainment/sports/media occupations. The NBR dataset should be further utilized for occupational burn injury investigations and multiple fields should be considered for case ascertainment.

Viewing the functional consequences of traumatic brain injury by using brain SPECT.

PubMed

Pavel, D; Jobe, T; Devore-Best, S; Davis, G; Epstein, P; Sinha, S; Kohn, R; Craita, I; Liu, P; Chang, Y

2006-03-01

High-resolution brain SPECT is increasingly benefiting from improved image processing software and multiple complementary display capabilities. This enables detailed functional mapping of the disturbances in relative perfusion occurring after TBI. The patient population consisted of 26 cases (ages 8-61 years)between 3 months and 6 years after traumatic brain injury.A very strong case can be made for the routine use of Brain SPECT in TBI. Indeed it can provide a detailed evaluation of multiple functional consequences after TBI and is thus capable of supplementing the clinical evaluation and tailoring the therapeutic strategies needed. In so doing it also provides significant additional information beyond that available from MRI/CT. The critical factor for Brain SPECT's clinical relevance is a carefully designed technical protocol, including displays which should enable a comprehensive description of the patterns found, in a user friendly mode.

A novel approach to exploring potential interactions among single-nucleotide polymorphisms of inflammation genes in gliomagenesis: an exploratory case-only study.

PubMed

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.

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.

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.

Multiple ligand simultaneous docking: orchestrated dancing of ligands in binding sites of protein.

PubMed

Li, Huameng; Li, Chenglong

2010-07-30

Present docking methodologies simulate only one single ligand at a time during docking process. In reality, the molecular recognition process always involves multiple molecular species. Typical protein-ligand interactions are, for example, substrate and cofactor in catalytic cycle; metal ion coordination together with ligand(s); and ligand binding with water molecules. To simulate the real molecular binding processes, we propose a novel multiple ligand simultaneous docking (MLSD) strategy, which can deal with all the above processes, vastly improving docking sampling and binding free energy scoring. The work also compares two search strategies: Lamarckian genetic algorithm and particle swarm optimization, which have respective advantages depending on the specific systems. The methodology proves robust through systematic testing against several diverse model systems: E. coli purine nucleoside phosphorylase (PNP) complex with two substrates, SHP2NSH2 complex with two peptides and Bcl-xL complex with ABT-737 fragments. In all cases, the final correct docking poses and relative binding free energies were obtained. In PNP case, the simulations also capture the binding intermediates and reveal the binding dynamics during the recognition processes, which are consistent with the proposed enzymatic mechanism. In the other two cases, conventional single-ligand docking fails due to energetic and dynamic coupling among ligands, whereas MLSD results in the correct binding modes. These three cases also represent potential applications in the areas of exploring enzymatic mechanism, interpreting noisy X-ray crystallographic maps, and aiding fragment-based drug design, respectively. 2010 Wiley Periodicals, Inc.

A robust approach towards unknown transformation, regional adjacency graphs, multigraph matching, segmentation video frames from unnamed aerial vehicles (UAV)

NASA Astrophysics Data System (ADS)

Gohatre, Umakant Bhaskar; Patil, Venkat P.

2018-04-01

In computer vision application, the multiple object detection and tracking, in real-time operation is one of the important research field, that have gained a lot of attentions, in last few years for finding non stationary entities in the field of image sequence. The detection of object is advance towards following the moving object in video and then representation of object is step to track. The multiple object recognition proof is one of the testing assignment from detection multiple objects from video sequence. The picture enrollment has been for quite some time utilized as a reason for the location the detection of moving multiple objects. The technique of registration to discover correspondence between back to back casing sets in view of picture appearance under inflexible and relative change. The picture enrollment is not appropriate to deal with event occasion that can be result in potential missed objects. In this paper, for address such problems, designs propose novel approach. The divided video outlines utilizing area adjancy diagram of visual appearance and geometric properties. Then it performed between graph sequences by using multi graph matching, then getting matching region labeling by a proposed graph coloring algorithms which assign foreground label to respective region. The plan design is robust to unknown transformation with significant improvement in overall existing work which is related to moving multiple objects detection in real time parameters.

Conjugate gradient determination of optimal plane changes for a class of three-impulse transfers between noncoplanar circular orbits

NASA Technical Reports Server (NTRS)

Burrows, R. R.

1972-01-01

A particular type of three-impulse transfer between two circular orbits is analyzed. The possibility of three plane changes is recognized, and the problem is to optimally distribute these plane changes to minimize the sum of the individual impulses. Numerical difficulties and their solution are discussed. Numerical results obtained from a conjugate gradient technique are presented for both the case where the individual plane changes are unconstrained and for the case where they are constrained. Possibly not unexpectedly, multiple minima are found. The techniques presented could be extended to the finite burn case, but primarily the contents are addressed to preliminary mission design and vehicle sizing.

Modular femoral neck fracture after primary total hip arthroplasty.

PubMed

Sotereanos, Nicholas G; Sauber, Timothy J; Tupis, Todd T

2013-01-01

The use of modular femoral stems in primary total hip arthroplasty has increased considerably in recent years. These modular components offer the surgeon the ability to independently alter version, offset, and length of the femoral component of a hip arthroplasty. This increases the surgeon's ability to accurately recreate the relevant anatomy but increases the possibilities of corrosion and fracture. Multiple case reports have highlighted fractures of these modular components. We present a case of a fracture of a modular design that has had no previously reported modular neck fractures. The patient was informed that data concerning the case would be submitted, and he consented. Copyright © 2013 Elsevier Inc. All rights reserved.

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.

Virtual patients design and its effect on clinical reasoning and student experience: a protocol for a randomised factorial multi-centre study.

PubMed

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.

A robust variable sampling time BLDC motor control design based upon μ-synthesis.

PubMed

Hung, Chung-Wen; Yen, Jia-Yush

2013-01-01

The variable sampling rate system is encountered in many applications. When the speed information is derived from the position marks along the trajectory, one would have a speed dependent sampling rate system. The conventional fixed or multisampling rate system theory may not work in these cases because the system dynamics include the uncertainties which resulted from the variable sampling rate. This paper derived a convenient expression for the speed dependent sampling rate system. The varying sampling rate effect is then translated into multiplicative uncertainties to the system. The design then uses the popular μ-synthesis process to achieve a robust performance controller design. The implementation on a BLDC motor demonstrates the effectiveness of the design approach.

A Robust Variable Sampling Time BLDC Motor Control Design Based upon μ-Synthesis

PubMed Central

Yen, Jia-Yush

2013-01-01

The variable sampling rate system is encountered in many applications. When the speed information is derived from the position marks along the trajectory, one would have a speed dependent sampling rate system. The conventional fixed or multisampling rate system theory may not work in these cases because the system dynamics include the uncertainties which resulted from the variable sampling rate. This paper derived a convenient expression for the speed dependent sampling rate system. The varying sampling rate effect is then translated into multiplicative uncertainties to the system. The design then uses the popular μ-synthesis process to achieve a robust performance controller design. The implementation on a BLDC motor demonstrates the effectiveness of the design approach. PMID:24327804

Effects of Swept Tips on V-22 Whirl Flutter and Loads

NASA Technical Reports Server (NTRS)

Acree, C. W., Jr.

2005-01-01

A CAMRAD II model of the V-22 Osprey tiltrotor was constructed for the purpose of analyzing the effects of blade design changes on whirl flutter. The model incorporated a dual load-path grip/yoke assembly, a swashplate coupled to the transmission case, and a drive train. A multiple-trailer free wake was used for loads calculations. The effects of rotor design changes on whirl-mode stability were calculated for swept blades and offset tip masses. A rotor with swept tips and inboard tuning masses was examined in detail to reveal the mechanisms by which these design changes affect stability and loads. Certain combinations of design features greatly increased whirl-mode stability, with (at worst) moderate increases to loads.

Aeronautical audio broadcasting via satellite

NASA Technical Reports Server (NTRS)

Tzeng, Forrest F.

1993-01-01

A system design for aeronautical audio broadcasting, with C-band uplink and L-band downlink, via Inmarsat space segments is presented. Near-transparent-quality compression of 5-kHz bandwidth audio at 20.5 kbit/s is achieved based on a hybrid technique employing linear predictive modeling and transform-domain residual quantization. Concatenated Reed-Solomon/convolutional codes with quadrature phase shift keying are selected for bandwidth and power efficiency. RF bandwidth at 25 kHz per channel, and a decoded bit error rate at 10(exp -6) with E(sub b)/N(sub o) at 3.75 dB are obtained. An interleaver, scrambler, modem synchronization, and frame format were designed, and frequency-division multiple access was selected over code-division multiple access. A link budget computation based on a worst-case scenario indicates sufficient system power margins. Transponder occupancy analysis for 72 audio channels demonstrates ample remaining capacity to accommodate emerging aeronautical services.

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.

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.

A Grounded Theory Approach to Understanding Ethical Leadership with School Leaders in Southern Nigeria: A Perspective of Three Primary Schools

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…

Academic Leadership: Management of Groups or Leadership of Teams? A Multiple-Case Study on Designing and Implementing a Team-Based Development Programme for Academic Leadership

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…

Teaching Functional Play Skills to a Young Child with Autism Spectrum Disorder through Video Self-Modeling

ERIC Educational Resources Information Center

Lee, Sharon Y.; Lo, Ya-yu; Lo, Yafen

2017-01-01

The researchers used a single-case, multiple probe design across three sets of toys (i.e., farm toy, doctor's clinic toy, and rescue toy) to examine the effects of video self-modeling (VSM) on the functional play skills of a 5-year-old child with autism spectrum disorder. The findings showed a functional relation between VSM and increased…

The Nature of the Interplay among Components of Pedagogical Content Knowledge in Reaction Rate and Chemical Equilibrium Topics of Novice and Experienced Chemistry Teachers

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…

Toward a Theory of Web-Mediated Knowledge Synthesis: How Advanced Learners Used the Web to Construct Knowledge about Climate Change Behavior

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…

Family Implementation of Positive Behavior Support for a Child with Autism: Longitudinal, Single-Case, Experimental, and Descriptive Replication and Extension

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…

MURI: Impact of Oceanographic Variability on Acoustic Communications

DTIC Science & Technology

2012-09-30

ACSSC.2010.5757934 (2010). [published] [50] K. Tu, T.M. Duman, J.G. Proakis, and M. Stojanovic, “Cooperative MIMO - OFDM communications: Receiver...considered across bands of frequencies in the range 1-50 kHz. Multiple source and receiver cases ( MIMO ) will be of particular interest. Validating...Parabolic Equation (PE) acoustic models. Communication receiver design has included processors for orthogonal frequency division multiplexing ( OFDM

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…

Effects of Modeling, Story Templates, and Self-Graphing in the Use of Story Elements by Students with Moderate Intellectual Disability

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…

Why Can't They Keep the Book Longer and Do We Really Need to Charge Fines? Assessing Circulation Policies at the Harold B. Lee Library: A Case Study

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…

Development and evaluation of a study design typology for human research.

PubMed

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.

Initial implementation and evaluation of a Hepatitis C treatment clinical decision support system (CDSS)

PubMed Central

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

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.

Interventions aimed at improving the ability to use everyday technology in work after brain injury.

PubMed

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.

Cross-continuum Care Continuity: Achieving Seamless Care and Managing Comorbidities.

PubMed

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.

A Platform-Independent Plugin for Navigating Online Radiology Cases.

PubMed

Balkman, Jason D; Awan, Omer A

2016-06-01

Software methods that enable navigation of radiology cases on various digital platforms differ between handheld devices and desktop computers. This has resulted in poor compatibility of online radiology teaching files across mobile smartphones, tablets, and desktop computers. A standardized, platform-independent, or "agnostic" approach for presenting online radiology content was produced in this work by leveraging modern hypertext markup language (HTML) and JavaScript web software technology. We describe the design and evaluation of this software, demonstrate its use across multiple viewing platforms, and make it publicly available as a model for future development efforts.

Launch Vehicle Propulsion Parameter Design Multiple Selection Criteria

NASA Technical Reports Server (NTRS)

Shelton, Joey Dewayne

2004-01-01

The optimization tool described herein addresses and emphasizes the use of computer tools to model a system and focuses on a concept development approach for a liquid hydrogen/liquid oxygen single-stage-to-orbit system, but more particularly the development of the optimized system using new techniques. This methodology uses new and innovative tools to run Monte Carlo simulations, genetic algorithm solvers, and statistical models in order to optimize a design concept. The concept launch vehicle and propulsion system were modeled and optimized to determine the best design for weight and cost by varying design and technology parameters. Uncertainty levels were applied using Monte Carlo Simulations and the model output was compared to the National Aeronautics and Space Administration Space Shuttle Main Engine. Several key conclusions are summarized here for the model results. First, the Gross Liftoff Weight and Dry Weight were 67% higher for the design case for minimization of Design, Development, Test and Evaluation cost when compared to the weights determined by the minimization of Gross Liftoff Weight case. In turn, the Design, Development, Test and Evaluation cost was 53% higher for optimized Gross Liftoff Weight case when compared to the cost determined by case for minimization of Design, Development, Test and Evaluation cost. Therefore, a 53% increase in Design, Development, Test and Evaluation cost results in a 67% reduction in Gross Liftoff Weight. Secondly, the tool outputs define the sensitivity of propulsion parameters, technology and cost factors and how these parameters differ when cost and weight are optimized separately. A key finding was that for a Space Shuttle Main Engine thrust level the oxidizer/fuel ratio of 6.6 resulted in the lowest Gross Liftoff Weight rather than at 5.2 for the maximum specific impulse, demonstrating the relationships between specific impulse, engine weight, tank volume and tank weight. Lastly, the optimum chamber pressure for Gross Liftoff Weight minimization was 2713 pounds per square inch as compared to 3162 for the Design, Development, Test and Evaluation cost optimization case. This chamber pressure range is close to 3000 pounds per square inch for the Space Shuttle Main Engine.

Design and implementation of multichannel global active structural acoustic control for a device casing

NASA Astrophysics Data System (ADS)

Mazur, Krzysztof; Wrona, Stanislaw; Pawelczyk, Marek

2018-01-01

The paper presents the idea and discussion on implementation of multichannel global active noise control systems. As a test plant an active casing is used. It has been developed by the authors to reduce device noise directly at the source by controlling vibration of its casing. To provide global acoustic effect in the whole environment, where the device operates, it requires a number of secondary sources and sensors for each casing wall, thus making the whole active control structure complicated, i.e. with a large number of interacting channels. The paper discloses all details concerning hardware setup and efficient implementation of control algorithms for the multichannel case. A new formulation is presented to introduce the distributed version of the Switched-error Filtered-reference Least Mean Squares (FXLMS) algorithm together with adaptation rate enhancement. The convergence rate of the proposed algorithm is compared with original Multiple-error FXLMS. A number of hints followed from many years of authors' experience on microprocessor control systems design and signal processing algorithms optimization are presented. They can be used for various active control and signal processing applications, both for academic research and commercialization.

Selection of Thermal Worst-Case Orbits via Modified Efficient Global Optimization

NASA Technical Reports Server (NTRS)

Moeller, Timothy M.; Wilhite, Alan W.; Liles, Kaitlin A.

2014-01-01

Efficient Global Optimization (EGO) was used to select orbits with worst-case hot and cold thermal environments for the Stratospheric Aerosol and Gas Experiment (SAGE) III. The SAGE III system thermal model changed substantially since the previous selection of worst-case orbits (which did not use the EGO method), so the selections were revised to ensure the worst cases are being captured. The EGO method consists of first conducting an initial set of parametric runs, generated with a space-filling Design of Experiments (DoE) method, then fitting a surrogate model to the data and searching for points of maximum Expected Improvement (EI) to conduct additional runs. The general EGO method was modified by using a multi-start optimizer to identify multiple new test points at each iteration. This modification facilitates parallel computing and decreases the burden of user interaction when the optimizer code is not integrated with the model. Thermal worst-case orbits for SAGE III were successfully identified and shown by direct comparison to be more severe than those identified in the previous selection. The EGO method is a useful tool for this application and can result in computational savings if the initial Design of Experiments (DoE) is selected appropriately.

Computations on Wings With Full-Span Oscillating Control Surfaces Using Navier-Stokes Equations

NASA Technical Reports Server (NTRS)

Guruswamy, Guru P.

2013-01-01

A dual-level parallel procedure is presented for computing large databases to support aerospace vehicle design. This procedure has been developed as a single Unix script within the Parallel Batch Submission environment utilizing MPIexec and runs MPI based analysis software. It has been developed to provide a process for aerospace designers to generate data for large numbers of cases with the highest possible fidelity and reasonable wall clock time. A single job submission environment has been created to avoid keeping track of multiple jobs and the associated system administration overhead. The process has been demonstrated for computing large databases for the design of typical aerospace configurations, a launch vehicle and a rotorcraft.

Integration of multi-objective structural optimization into cementless hip prosthesis design: Improved Austin-Moore model.

PubMed

Kharmanda, G

2016-11-01

A new strategy of multi-objective structural optimization is integrated into Austin-Moore prosthesis in order to improve its performance. The new resulting model is so-called Improved Austin-Moore. The topology optimization is considered as a conceptual design stage to sketch several kinds of hollow stems according to the daily loading cases. The shape optimization presents the detailed design stage considering several objectives. Here, A new multiplicative formulation is proposed as a performance scale in order to define the best compromise between several requirements. Numerical applications on 2D and 3D problems are carried out to show the advantages of the proposed model.

Architecture for multi-technology real-time location systems.

PubMed

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.

Design and Analysis of the Warm-To Suspension Links for Jefferson Lab's 11 Gev/c Super High Momentum Spectrometer

NASA Astrophysics Data System (ADS)

Sun, E.; Brindza, P.; Lassiter, S.; Fowler, M.

2010-04-01

This paper describes design and analysis performed for the warm-to-cold suspension links of the warm iron yoke superconducting quadrupole magnets, and superconducting dipole magnet. The results of investigation of titanium Ti-6Al-4V and Nitronic 50 stainless steel for the suspension links to support the cold mass, preloads, forces due to cryogenic temperature, and imbalanced magnetic forces from misalignments are presented. Allowable stresses at normal-case scenarios and worst-case scenarios, space constraints, and heat leak considerations are discussed. Principles of the ASME Pressure Vessel Code were used to determine allowable stresses. Optimal angles of the suspension links were obtained by calculation and finite element methods. The stress levels of suspension links at multiple scenarios are presented, discussed, and compared with the allowable stresses.

Farmer responses to multiple stresses in the face of global change: Assessing five case studies to enhance adaptation

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.

Modular Matrix Multiplication on a Linear Array.

DTIC Science & Technology

1983-11-01

is fl(n2). 2 Case e Irl __ (see Figure 5.2) 2 2 ,1 Y, " X2v- ’ Y2 -. x= -- ~ Y4 "i; Yin Figure 5Ŗ At t--xi, either all Gk, such that IkEA , have n...nat and Image Proceuing, IEEE Transactions on Computers, Vol. C-31, No. 10 22 (October, 1982), pp. IO0oo09. [41 H.T. Kung, Let’s Design Algorithms for...VLSI Systems, Proc. Caltech Conf. on Very Large Scale Integration: Architecture, Design , Fabrication (January, 1979), pp. 65. 90. 151 H.T. Kung, and

Evaluating the Effect of Minimizing Screws on Stabilization of Symphysis Mandibular Fracture by 3D Finite Element Analysis.

PubMed

Kharmanda, Ghias; Kharma, Mohamed-Yaser

2017-06-01

The objective of this work is to integrate structural optimization and reliability concepts into mini-plate fixation strategy used in symphysis mandibular fractures. The structural reliability levels are next estimated when considering a single failure mode and multiple failure modes. A 3-dimensional finite element model is developed in order to evaluate the ability of reducing the negative effect due to the stabilization of the fracture. Topology optimization process is considered in the conceptual design stage to predict possible fixation layouts. In the detailed design stage, suitable mini-plates are selected taking into account the resulting topology and different anatomical considerations. Several muscle forces are considered in order to obtain realistic predictions. Since some muscles can be cut or harmed during the surgery and cannot operate at its maximum capacity, there is a strong motivation to introduce the loading uncertainties in order to obtain reliable designs. The structural reliability is carried out for a single failure mode and multiple failure modes. The different results are validated with a clinical case of a male patient with symphysis fracture. In this case while use of the upper plate fixation with four holes, only two screws were applied to protect adjacent vital structure. This behavior does not affect the stability of the fracture. The proposed strategy to optimize bone plates leads to fewer complications and second surgeries, less patient discomfort, and shorter time of healing.

Effects of Acupuncture on Gait of Patients with Multiple Sclerosis.

PubMed

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.

Sampled-data-based consensus and containment control of multiple harmonic oscillators: A motion-planning approach

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.

Report for simultaneous, multiple independently steered beam study for Airborne Electronically Steerable Phased Array (AESPA) program

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.

Predicting the stability of a compressible periodic parallel jet flow

NASA Technical Reports Server (NTRS)

Miles, Jeffrey H.

1996-01-01

It is known that mixing enhancement in compressible free shear layer flows with high convective Mach numbers is difficult. One design strategy to get around this is to use multiple nozzles. Extrapolating this design concept in a one dimensional manner, one arrives at an array of parallel rectangular nozzles where the smaller dimension is omega and the longer dimension, b, is taken to be infinite. In this paper, the feasibility of predicting the stability of this type of compressible periodic parallel jet flow is discussed. The problem is treated using Floquet-Bloch theory. Numerical solutions to this eigenvalue problem are presented. For the case presented, the interjet spacing, s, was selected so that s/omega =2.23. Typical plots of the eigenvalue and stability curves are presented. Results obtained for a range of convective Mach numbers from 3 to 5 show growth rates omega(sub i)=kc(sub i)/2 range from 0.25 to 0.29. These results indicate that coherent two-dimensional structures can occur without difficulty in multiple parallel periodic jet nozzles and that shear layer mixing should occur with this type of nozzle design.

Idiopathic multiple impacted unerupted teeth: Case report and discussion

PubMed Central

Sujatha, G; Sivapathasundharam, B; Sivakumar, G; Nalinkumar, S; Ramasamy, M; Prasad, T Srinivasa

2012-01-01

Multiple impacted permanent teeth are usually related to syndromes, metabolic and hormonal disorders. However, in some cases, impaction of multiple teeth is not associated with any syndrome. In this report, we present a case of 17-year-old male patient with missing teeth. Radiographs revealed multiple impacted permanent teeth, though medical and family history along with physical examination was not suggestive of any syndromes. If other investigations are negative, an idiopathic case of multiple impacted teeth is suggested to be the possible diagnosis. The objective of this report is to increase awareness of such cases especially in the absence of hereditary/genetic/metabolic factors usually inherent in such scenarios. The patient management in such cases needs to be planned specifically from a multidisciplinary standpoint. PMID:22438652

Design of microarray experiments for genetical genomics studies.

PubMed

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.

Action Research of an Error Self-Correction Intervention: Examining the Effects on the Spelling Accuracy Behaviors of Fifth-Grade Students Identified as At-Risk

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'…

Effects of the Practiced Routines Parent Training Program on Behavioral Strategy Use, Parental Well-Being, and Child Challenging Behavior in Parents of Children with Autism Spectrum Disorder

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…

Graduate Transition into Work: The Bridging Role of Graduate Placement Programmes in the Small- and Medium-Sized Enterprise Workplace

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…

Designing for Online Collaborations and Local Environmental Action In Citizen Science: A Multiple Case Study

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.

Terahertz bandwidth all-optical Hilbert transformers based on long-period gratings.

PubMed

Ashrafi, Reza; Azaña, José

2012-07-01

A novel, all-optical design for implementing terahertz (THz) bandwidth real-time Hilbert transformers is proposed and numerically demonstrated. An all-optical Hilbert transformer can be implemented using a uniform-period long-period grating (LPG) with a properly designed amplitude-only grating apodization profile, incorporating a single π-phase shift in the middle of the grating length. The designed LPG-based Hilbert transformers can be practically implemented using either fiber-optic or integrated-waveguide technologies. As a generalization, photonic fractional Hilbert transformers are also designed based on the same optical platform. In this general case, the resulting LPGs have multiple π-phase shifts along the grating length. Our numerical simulations confirm that all-optical Hilbert transformers capable of processing arbitrary optical signals with bandwidths well in the THz range can be implemented using feasible fiber/waveguide LPG designs.

Anomalous Cases of Astronaut Helmet Detection

NASA Technical Reports Server (NTRS)

Dolph, Chester; Moore, Andrew J.; Schubert, Matthew; Woodell, Glenn

2015-01-01

An astronaut's helmet is an invariant, rigid image element that is well suited for identification and tracking using current machine vision technology. Future space exploration will benefit from the development of astronaut detection software for search and rescue missions based on EVA helmet identification. However, helmets are solid white, except for metal brackets to attach accessories such as supplementary lights. We compared the performance of a widely used machine vision pipeline on a standard-issue NASA helmet with and without affixed experimental feature-rich patterns. Performance on the patterned helmet was far more robust. We found that four different feature-rich patterns are sufficient to identify a helmet and determine orientation as it is rotated about the yaw, pitch, and roll axes. During helmet rotation the field of view changes to frames containing parts of two or more feature-rich patterns. We took reference images in these locations to fill in detection gaps. These multiple feature-rich patterns references added substantial benefit to detection, however, they generated the majority of the anomalous cases. In these few instances, our algorithm keys in on one feature-rich pattern of the multiple feature-rich pattern reference and makes an incorrect prediction of the location of the other feature-rich patterns. We describe and make recommendations on ways to mitigate anomalous cases in which detection of one or more feature-rich patterns fails. While the number of cases is only a small percentage of the tested helmet orientations, they illustrate important design considerations for future spacesuits. In addition to our four successful feature-rich patterns, we present unsuccessful patterns and discuss the cause of their poor performance from a machine vision perspective. Future helmets designed with these considerations will enable automated astronaut detection and thereby enhance mission operations and extraterrestrial search and rescue.

Spatial curvilinear path following control of underactuated AUV with multiple uncertainties.

PubMed

Miao, Jianming; Wang, Shaoping; Zhao, Zhiping; Li, Yuan; Tomovic, Mileta M

2017-03-01

This paper investigates the problem of spatial curvilinear path following control of underactuated autonomous underwater vehicles (AUVs) with multiple uncertainties. Firstly, in order to design the appropriate controller, path following error dynamics model is constructed in a moving Serret-Frenet frame, and the five degrees of freedom (DOFs) dynamic model with multiple uncertainties is established. Secondly, the proposed control law is separated into kinematic controller and dynamic controller via back-stepping technique. In the case of kinematic controller, to overcome the drawback of dependence on the accurate vehicle model that are present in a number of path following control strategies described in the literature, the unknown side-slip angular velocity and attack angular velocity are treated as uncertainties. Whereas in the case of dynamic controller, the model parameters perturbations, unknown external environmental disturbances and the nonlinear hydrodynamic damping terms are treated as lumped uncertainties. Both kinematic and dynamic uncertainties are estimated and compensated by designed reduced-order linear extended state observes (LESOs). Thirdly, feedback linearization (FL) based control law is implemented for the control model using the estimates generated by reduced-order LESOs. For handling the problem of computational complexity inherent in the conventional back-stepping method, nonlinear tracking differentiators (NTDs) are applied to construct derivatives of the virtual control commands. Finally, the closed loop stability for the overall system is established. Simulation and comparative analysis demonstrate that the proposed controller exhibits enhanced performance in the presence of internal parameter variations, external unknown disturbances, unmodeled nonlinear damping terms, and measurement noises. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Experience with Using Multiple Types of Visual Educational Tools during Problem-Based Learning.

PubMed

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.

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.

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.

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.

Mamun-TKC parathyroid retractor: Parathyroid glands squashed or scooped!

PubMed

Mahmud, Syed Mamun

2015-03-01

Parathyroid gland by its physiologic and anatomic diversity has interestingly been dealt by multiple specialties, including Urology. Besides primary hyperparathyroidism, urologists in close working relationship with nephrologists, tend to get referrals for tertiary hyperparathyroidism. Data from 1999 to 2012 was retrieved for all parathyroidectomies. Medical record of only cases undergoing parathyroidectomy utilising the instrument Mamun-TKC Parathyroid Retractor were reviewed. It is a metal body surgical instrument resembling Gil Vernet retractor having functional flat metal head attached to solid long handle, designed in two forms; one 'Straight' and other 'Angled' at 30°. During the period, 28 cases of parathyroidectomies were performed. The instrument was used in two cases. It was found to facilitate dissection, retraction and pedicle ligation of parathyroid gland by a-traumatic handling.

Multiple spinal metastases from a well-differentiated liposarcoma of the iliac wing: a case report

PubMed Central

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

[Multiple myeloma and HIV infection: report of 3 cases].

PubMed

Elira Dokekias, A; Moutschen, M; Purhuence, M F; Malanda, F; Moyikoua, A

2004-02-01

HIV infection rages at the endemic state in Sub Saharan African and especially in Congo Brazzaville. We report the observation of three female patients infected with HIV and developing multiple myeloma. The three patients were treated at the University hospital of Brazzaville between 2000 and 2002. In two cases multiple myeloma was discovered after the diagnosis of HIV infection. In the other case, the diagnosis of HIV infection was posterior to the occurrence of multiple myeloma. HIV infection was symptomatic in two cases who received consequently antiviral treatment. Multiple myeloma was diagnosed at an advanced stage in the three cases. The paraprotein was an IgG in two cases and an IgA in the other one. The CD4 counts before treatment were around 200/mm3 in two cases and within normal limits in the third case. Viral load was not measured. VMCP and VAMCP regimens were administered without major complications and under anti-infectious prophylaxis. The follow-up is still insufficient to assess the medium-term evolution and to determine the prognosis of multiple myeloma. The description of these three cases confirms the involvement of HIV in B cell lymphoma genesis.

Rationale of technical requirements for NRG-BR001: The first NCI-sponsored trial of SBRT for the treatment of multiple metastases.

PubMed

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.

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.

Understanding the Relationship Between Teacher Behavior and Motivation in Students with Acquired Deafblindness.

PubMed

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.

Web-Based Architecture to Enable Compute-Intensive CAD Tools and Multi-user Synchronization in Teleradiology

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.

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.

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.

Student ownership of projects in an upper-division optics laboratory course: A multiple case study of successful experiences

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.

Case Study Observational Research: A Framework for Conducting Case Study Research Where Observation Data Are the Focus.

PubMed

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.

Exploring role confusion in nurse case management.

PubMed

Gray, Frances C; White, Ann; Brooks-Buck, Judith

2013-01-01

This is a report of the results of a pilot project conducted to identify the areas where role confusion/ambiguity exists in the practice of nurse case management. A convenience sample of 25 registered nurses practicing as case managers in a small east coast medical treatment facility's outpatient clinics. Participants responded to 2 Likert-type surveys designed to evaluate role confusion from an individual and a team membership perspective. Analysis indicated that nurse case managers experience role confusion in the specific areas of conflicts between time resources, capabilities, and multiple individual roles. There was no identified role confusion associated with membership on multidisciplinary teams. The application of the Synergy Model as a theoretical framework for nurse case management serves as a benchmark for the implementation of evidence-based practices. This project could serve as the starting point for the development of a skill set for nurse case managers, for the standardization of the practice, and for the recognition of nurse case management as a legitimate nursing subspecialty.

The effect of class imbalance on case selection for case-based classifiers: An empirical study in the context of medical decision support

PubMed Central

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

Applications of active adaptive noise control to jet engines

NASA Technical Reports Server (NTRS)

Shoureshi, Rahmat; Brackney, Larry

1993-01-01

During phase 2 research on the application of active noise control to jet engines, the development of multiple-input/multiple-output (MIMO) active adaptive noise control algorithms and acoustic/controls models for turbofan engines were considered. Specific goals for this research phase included: (1) implementation of a MIMO adaptive minimum variance active noise controller; and (2) turbofan engine model development. A minimum variance control law for adaptive active noise control has been developed, simulated, and implemented for single-input/single-output (SISO) systems. Since acoustic systems tend to be distributed, multiple sensors, and actuators are more appropriate. As such, the SISO minimum variance controller was extended to the MIMO case. Simulation and experimental results are presented. A state-space model of a simplified gas turbine engine is developed using the bond graph technique. The model retains important system behavior, yet is of low enough order to be useful for controller design. Expansion of the model to include multiple stages and spools is also discussed.

Layout-aware simulation of soft errors in sub-100 nm integrated circuits

NASA Astrophysics Data System (ADS)

Balbekov, A.; Gorbunov, M.; Bobkov, S.

2016-12-01

Single Event Transient (SET) caused by charged particle traveling through the sensitive volume of integral circuit (IC) may lead to different errors in digital circuits in some cases. In technologies below 180 nm, a single particle can affect multiple devices causing multiple SET. This fact adds the complexity to fault tolerant devices design, because the schematic design techniques become useless without their layout consideration. The most common layout mitigation technique is a spatial separation of sensitive nodes of hardened circuits. Spatial separation decreases the circuit performance and increases power consumption. Spacing should thus be reasonable and its scaling follows the device dimensions' scaling trend. This paper presents the development of the SET simulation approach comprised of SPICE simulation with "double exponent" current source as SET model. The technique uses layout in GDSII format to locate nearby devices that can be affected by a single particle and that can share the generated charge. The developed software tool automatizes multiple simulations and gathers the produced data to present it as the sensitivity map. The examples of conducted simulations of fault tolerant cells and their sensitivity maps are presented in this paper.

Sample size determination for equivalence assessment with multiple endpoints.

PubMed

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.

A method for joint routing, wavelength dimensioning and fault tolerance for any set of simultaneous failures on dynamic WDM optical networks

NASA Astrophysics Data System (ADS)

Jara, Nicolás; Vallejos, Reinaldo; Rubino, Gerardo

2017-11-01

The design of optical networks decomposes into different tasks, where the engineers must basically organize the way the main system's resources are used, minimizing the design and operation costs and respecting critical performance constraints. More specifically, network operators face the challenge of solving routing and wavelength dimensioning problems while aiming to simultaneously minimize the network cost and to ensure that the network performance meets the level established in the Service Level Agreement (SLA). We call this the Routing and Wavelength Dimensioning (R&WD) problem. Another important problem to be solved is how to deal with failures of links when the network is operating. When at least one link fails, a high rate of data loss may occur. To avoid it, the network must be designed in such a manner that upon one or multiple failures, the affected connections can still communicate using alternative routes, a mechanism known as Fault Tolerance (FT). When the mechanism allows to deal with an arbitrary number of faults, we speak about Multiple Fault Tolerance (MFT). The different tasks before mentioned are usually solved separately, or in some cases by pairs, leading to solutions that are not necessarily close to optimal ones. This paper proposes a novel method to simultaneously solve all of them, that is, the Routing, the Wavelength Dimensioning, and the Multiple Fault Tolerance problems. The method allows to obtain: a) all the primary routes by which each connection normally transmits its information, b) the additional routes, called secondary routes, used to keep each user connected in cases where one or more simultaneous failures occur, and c) the number of wavelengths available at each link of the network, calculated such that the blocking probability of each connection is lower than a pre-determined threshold (which is a network design parameter), despite the occurrence of simultaneous link failures. The solution obtained by the new algorithm is significantly more efficient than current methods, its implementation is notably simple and its on-line operation is very fast. In the paper, different examples illustrate the results provided by the proposed technique.

Do Affordable Housing Projects Harm Suburban Communities? Crime, Property Values, and Taxes in Mount Laurel, NJ.

PubMed

Albright, Len; Derickson, Elizabeth S; Massey, Douglas S

2013-06-01

This paper offers a mixed-method analysis of the municipal-level consequences of an affordable housing development built in suburban New Jersey. Opponents of affordable housing development often suggest that creating affordable housing will harm surrounding communities. Feared consequences include increases in crime, declining property values, and rising taxes. To evaluate these claims, the paper uses the case of Mt. Laurel, NJ - the site of a landmark affordable housing legal case and subsequent affordable housing development. Employing a multiple time series group control design, we compare crime rates, property values, and property taxes in Mt. Laurel to outcomes in similar nearby municipalities that do not contain comparable affordable housing developments. We find that the opening of the affordable housing development was not associated with trends in crime, property values, or taxes, and discuss management practices and design features that may have mitigated potential negative externalities.

Reconfigurable intelligent sensors for health monitoring: a case study of pulse oximeter sensor.

PubMed

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.

Do Affordable Housing Projects Harm Suburban Communities? Crime, Property Values, and Taxes in Mount Laurel, NJ

PubMed Central

Albright, Len; Derickson, Elizabeth S.; Massey, Douglas S.

2016-01-01

This paper offers a mixed-method analysis of the municipal-level consequences of an affordable housing development built in suburban New Jersey. Opponents of affordable housing development often suggest that creating affordable housing will harm surrounding communities. Feared consequences include increases in crime, declining property values, and rising taxes. To evaluate these claims, the paper uses the case of Mt. Laurel, NJ – the site of a landmark affordable housing legal case and subsequent affordable housing development. Employing a multiple time series group control design, we compare crime rates, property values, and property taxes in Mt. Laurel to outcomes in similar nearby municipalities that do not contain comparable affordable housing developments. We find that the opening of the affordable housing development was not associated with trends in crime, property values, or taxes, and discuss management practices and design features that may have mitigated potential negative externalities. PMID:27390552

Quality of Diagnosis and Treatment Plans After Using the 'Diagnostic Guideline for Anxiety and Challenging Behaviours' in People with Intellectual Disabilities: A Comparative Multiple Case Study Design.

PubMed

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.

Substance Use and Self-Harm: Case Studies From Patients Admitted to an Urban Hospital Following Medically Serious Self-Harm.

PubMed

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.

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.

Learn and apply: using multi-sensory storytelling to gather knowledge about preferences and abilities of children with profound intellectual and multiple disabilities--three case studies.

PubMed

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.

Novel and general approach to linear filter design for contrast-to-noise ratio enhancement of magnetic resonance images with multiple interfering features in the scene

NASA Astrophysics Data System (ADS)

Soltanian-Zadeh, Hamid; Windham, Joe P.

1992-04-01

Maximizing the minimum absolute contrast-to-noise ratios (CNRs) between a desired feature and multiple interfering processes, by linear combination of images in a magnetic resonance imaging (MRI) scene sequence, is attractive for MRI analysis and interpretation. A general formulation of the problem is presented, along with a novel solution utilizing the simple and numerically stable method of Gram-Schmidt orthogonalization. We derive explicit solutions for the case of two interfering features first, then for three interfering features, and, finally, using a typical example, for an arbitrary number of interfering feature. For the case of two interfering features, we also provide simplified analytical expressions for the signal-to-noise ratios (SNRs) and CNRs of the filtered images. The technique is demonstrated through its applications to simulated and acquired MRI scene sequences of a human brain with a cerebral infarction. For these applications, a 50 to 100% improvement for the smallest absolute CNR is obtained.

Architecture for Multi-Technology Real-Time Location Systems

PubMed Central

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.

PubMed

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 adaptive actuator failure compensation scheme for two linked 2WD mobile robots

NASA Astrophysics Data System (ADS)

Ma, Yajie; Al-Dujaili, Ayad; Cocquempot, Vincent; El Badaoui El Najjar, Maan

2017-01-01

This paper develops a new adaptive compensation control scheme for two linked mobile robots with actuator failurs. A configuration with two linked two-wheel drive (2WD) mobile robots is proposed, and the modelling of its kinematics and dynamics are given. An adaptive failure compensation scheme is developed to compensate actuator failures, consisting of a kinematic controller and a multi-design integration based dynamic controller. The kinematic controller is a virtual one, and based on which, multiple adaptive dynamic control signals are designed which covers all possible failure cases. By combing these dynamic control signals, the dynamic controller is designed, which ensures system stability and asymptotic tracking properties. Simulation results verify the effectiveness of the proposed adaptive failure compensation scheme.

High Temperature Variable Conductance Heat Pipes for Radioisotope Stirling Systems

NASA Technical Reports Server (NTRS)

Tarau, Calin; Walker, Kara L.; Anderson, William G.

2009-01-01

In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) is under development to allow multiple stops and restarts of the Stirling convertor. The status of the ongoing effort in developing this technology is presented in this paper. An earlier, preliminary design had a radiator outside the Advanced Stirling Radioisotope Generator (ASRG) casing, used NaK as the working fluid, and had the reservoir located on the cold side adapter flange. The revised design has an internal radiator inside the casing, with the reservoir embedded inside the insulation. A large set of advantages are offered by this new design. In addition to reducing the overall size and mass of the VCHP, simplicity, compactness and easiness in assembling the VCHP with the ASRG are significantly enhanced. Also, the permanently elevated temperatures of the entire VCHP allows the change of the working fluid from a binary compound (NaK) to single compound (Na). The latter, by its properties, allows higher performance and further mass reduction of the system. Preliminary design and analysis shows an acceptable peak temperature of the ASRG case of 140 C while the heat losses caused by the addition of the VCHP are 1.8 W.

Polymorphic Electronic Circuits

NASA Technical Reports Server (NTRS)

Stoica, Adrian

2004-01-01

Polymorphic electronics is a nascent technological discipline that involves, among other things, designing the same circuit to perform different analog and/or digital functions under different conditions. For example, a circuit can be designed to function as an OR gate or an AND gate, depending on the temperature (see figure). Polymorphic electronics can also be considered a subset of polytronics, which is a broader technological discipline in which optical and possibly other information- processing systems could also be designed to perform multiple functions. Polytronics is an outgrowth of evolvable hardware (EHW). The basic concepts and some specific implementations of EHW were described in a number of previous NASA Tech Briefs articles. To recapitulate: The essence of EHW is to design, construct, and test a sequence of populations of circuits that function as incrementally better solutions of a given design problem through the selective, repetitive connection and/or disconnection of capacitors, transistors, amplifiers, inverters, and/or other circuit building blocks. The evolution is guided by a search-and-optimization algorithm (in particular, a genetic algorithm) that operates in the space of possible circuits to find a circuit that exhibits an acceptably close approximation of the desired functionality. The evolved circuits can be tested by computational simulation (in which case the evolution is said to be extrinsic), tested in real hardware (in which case the evolution is said to be intrinsic), or tested in random sequences of computational simulation and real hardware (in which case the evolution is said to be mixtrinsic).

Magnetic Signature: Small Arms Testing of Multiple Examples of Same Model Weapons

DTIC Science & Technology

2009-04-01

inside the wooden building, showing a three-axis fluxgate magnetometer , north-south path lines, and instrumentation system...the FVM-400 Vector Fluxgate Magnetometer by Macintyre Electronics Design Associates, Inc. (MEDA) was used and in other cases two DFM100G2 Digital... Fluxgate Magnetometers made by Billingsley Magnetics were used. The majority of the data obtained was done with the latter. The MEDA has a 1 nT

A Decision-Support System for Sustainable Water Distribution System Planning.

PubMed

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.

Changes in Educational Practices: A Multiple Case Study Investigating Faculty Implemented Changes in Educational Practices Designed to Meet the Academic Needs of the Contemporary Student at a Southwestern Community College

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…

ACT Payload Shroud Structural Concept Analysis and Optimization

NASA Technical Reports Server (NTRS)

Zalewski, Bart B.; Bednarcyk, Brett A.

2010-01-01

Aerospace structural applications demand a weight efficient design to perform in a cost effective manner. This is particularly true for launch vehicle structures, where weight is the dominant design driver. The design process typically requires many iterations to ensure that a satisfactory minimum weight has been obtained. Although metallic structures can be weight efficient, composite structures can provide additional weight savings due to their lower density and additional design flexibility. This work presents structural analysis and weight optimization of a composite payload shroud for NASA s Ares V heavy lift vehicle. Two concepts, which were previously determined to be efficient for such a structure are evaluated: a hat stiffened/corrugated panel and a fiber reinforced foam sandwich panel. A composite structural optimization code, HyperSizer, is used to optimize the panel geometry, composite material ply orientations, and sandwich core material. HyperSizer enables an efficient evaluation of thousands of potential designs versus multiple strength and stability-based failure criteria across multiple load cases. HyperSizer sizing process uses a global finite element model to obtain element forces, which are statistically processed to arrive at panel-level design-to loads. These loads are then used to analyze each candidate panel design. A near optimum design is selected as the one with the lowest weight that also provides all positive margins of safety. The stiffness of each newly sized panel or beam component is taken into account in the subsequent finite element analysis. Iteration of analysis/optimization is performed to ensure a converged design. Sizing results for the hat stiffened panel concept and the fiber reinforced foam sandwich concept are presented.

Staff and students' perceptions and experiences of teaching and assessment in Clinical Skills Laboratories: interview findings from a multiple case study.

PubMed

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.

Challenges of Implementing a Communication-and-Resolution Program Where Multiple Organizations Must Cooperate.

PubMed

Mello, Michelle M; Armstrong, Sarah J; Greenberg, Yelena; McCotter, Patricia I; Gallagher, Thomas H

2016-12-01

To implement a communication-and-resolution program (CRP) in a setting in which liability insurers and health care facilities must collaborate to resolve incidents involving a facility and separately insured clinicians. Six hospitals and clinics and a liability insurer in Washington State. Sites designed and implemented CRPs and contributed information about cases and operational challenges over 20 months. Data were qualitatively analyzed. Data from interviews with personnel responsible for CRP implementation were triangulated with data on program cases collected by sites and notes recorded during meetings with sites and among project team members. Sites experienced small victories in resolving particular cases and streamlining some working relationships, but they were unable to successfully implement a collaborative CRP. Barriers included the insurer's distance from the point of care, passive rather than active support from top leaders, coordinating across departments and organizations, workload, nonparticipation by some physicians, and overcoming distrust. Operating CRPs where multiple organizations must collaborate can be highly challenging. Success likely requires several preconditions, including preexisting trust among organizations, active leadership engagement, physicians' commitment to participate, mechanisms for quickly transmitting information to insurers, tolerance for missteps, and clear protocols for joint investigations and resolutions. © Health Research and Educational Trust.

Multiple regression for physiological data analysis: the problem of multicollinearity.

PubMed

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.

Coding Response to a Case-Mix Measurement System Based on Multiple Diagnoses

PubMed Central

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

Impact of interdisciplinary learning on critical thinking using case study method in allied health care graduate students.

PubMed

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.

Development of a 300 Amp-hr high rate lithium thionyl chloride cell

NASA Technical Reports Server (NTRS)

Boyle, Gerard H.

1991-01-01

The development of a high-rate lithium thionyl chloride cylindrical cell with parallel plate electrodes is discussed. The development was divided into three phases: phase 1, a 150 Amp/hour low rate (1 mA/sq cm) design; phase 2, a 25 Amp/hour high rate (5 mA/sq cm) design; and phase 3, a 300 Amp/hour high rate (5 mA/sq cm) design. The basic design is the same for all three cells. The electrodes are perpendicular to the axis of the cylinder. Multiple electrodes are bussed up the side of the cylinder, 180 deg apart allowing excellent anode and cathode utilization. It is a lithium limited design with excess electrolyte. The cathode is Shawinigan or Gulf Acetylene black with no catalyst. The electrolyte is 1.8 Molar lithium tetrachloroaluminate (LiAlCl4) in thionyl chloride. All cell cases are 304L Stainless Steel with a BS&B burst disc.

Analysis of multiple activity manual materials handling tasks using A Guide to Manual Materials Handling.

PubMed

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.

[Tuberculosis patient disease knowledge, attitudes and behavioral intentions: the impact of individualized counseling].

PubMed

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.

Pathology Competencies for Medical Education and Educational Cases.

PubMed

Knollmann-Ritschel, Barbara E C; Regula, Donald P; Borowitz, Michael J; Conran, Richard; Prystowsky, Michael B

2017-01-01

Current medical school curricula predominantly facilitate early integration of basic science principles into clinical practice to strengthen diagnostic skills and the ability to make treatment decisions. In addition, they promote life-long learning and understanding of the principles of medical practice. The Pathology Competencies for Medical Education (PCME) were developed in response to a call to action by pathology course directors nationwide to teach medical students pathology principles necessary for the practice of medicine. The PCME are divided into three competencies: 1) Disease Mechanisms and Processes, 2) Organ System Pathology, and 3) Diagnostic Medicine and Therapeutic Pathology. Each of these competencies is broad and contains multiple learning goals with more specific learning objectives. The original competencies were designed to be a living document, meaning that they will be revised and updated periodically, and have undergone their first revision with this publication. The development of teaching cases, which have a classic case-based design, for the learning objectives is the next step in providing educational content that is peer-reviewed and readily accessible for pathology course directors, medical educators, and medical students. Application of the PCME and cases promotes a minimum standard of exposure of the undifferentiated medical student to pathophysiologic principles. The publication of the PCME and the educational cases will create a current educational resource and repository published through Academic Pathology .

Transcending Landscapes: Working Across Scales and Levels in Pastoralist Rangeland Governance

NASA Astrophysics Data System (ADS)

Robinson, Lance W.; Ontiri, Enoch; Alemu, Tsegaye; Moiko, Stephen S.

2017-08-01

Landscape approaches can be subjected to mistakenly targeting a single "best" level of governance, and paying too little attention to the role that cross-scale and cross-level interactions play in governance. In rangeland settings, resources, patterns of use of those resources, and the institutions for managing the resources exist at multiple levels and scales. While the scholarship on commons offers some guidance on how to conceptualize governance in rangeland landscapes, some elements of commons scholarship—notably the "design principles" for effective governance of commons—do not seem to apply neatly to governance in pastoralist rangeland settings. This paper examines three cases where attempts have been made to foster effective landscape governance in such settings to consider how the materiality of commons influences the nature of cross-scale and cross-level interactions, and how these interactions affect governance. In all three cases, although external actors seemed to work appropriately and effectively at community and landscape levels, landscape governance mechanisms have been facing great challenges arising from relationships beyond the landscape, both vertically to higher levels of decision-making and horizontally to communities normally residing in other landscapes. The cases demonstrate that fostering effective landscape-level governance cannot be accomplished only through action at the landscape level; it is a task that must be pursued at multiple levels and in relation to the connections across scales and levels. The paper suggests elements of a conceptual framework for understanding cross-level and cross-scale elements of landscape governance, and offers suggestions for governance design in pastoralist rangeland settings.

Transcending Landscapes: Working Across Scales and Levels in Pastoralist Rangeland Governance.

PubMed

Robinson, Lance W; Ontiri, Enoch; Alemu, Tsegaye; Moiko, Stephen S

2017-08-01

Landscape approaches can be subjected to mistakenly targeting a single "best" level of governance, and paying too little attention to the role that cross-scale and cross-level interactions play in governance. In rangeland settings, resources, patterns of use of those resources, and the institutions for managing the resources exist at multiple levels and scales. While the scholarship on commons offers some guidance on how to conceptualize governance in rangeland landscapes, some elements of commons scholarship-notably the "design principles" for effective governance of commons-do not seem to apply neatly to governance in pastoralist rangeland settings. This paper examines three cases where attempts have been made to foster effective landscape governance in such settings to consider how the materiality of commons influences the nature of cross-scale and cross-level interactions, and how these interactions affect governance. In all three cases, although external actors seemed to work appropriately and effectively at community and landscape levels, landscape governance mechanisms have been facing great challenges arising from relationships beyond the landscape, both vertically to higher levels of decision-making and horizontally to communities normally residing in other landscapes. The cases demonstrate that fostering effective landscape-level governance cannot be accomplished only through action at the landscape level; it is a task that must be pursued at multiple levels and in relation to the connections across scales and levels. The paper suggests elements of a conceptual framework for understanding cross-level and cross-scale elements of landscape governance, and offers suggestions for governance design in pastoralist rangeland settings.

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.

DEVELOPING A VACCINE AGAINST MULTIPLE PSYCHOACTIVE TARGETS: A CASE STUDY OF HEROIN

PubMed Central

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

MIMO-OFDM signal optimization for SAR imaging radar

NASA Astrophysics Data System (ADS)

Baudais, J.-Y.; Méric, S.; Riché, V.; Pottier, É.

2016-12-01

This paper investigates the optimization of the coded orthogonal frequency division multiplexing (OFDM) transmitted signal in a synthetic aperture radar (SAR) context. We propose to design OFDM signals to achieve range ambiguity mitigation. Indeed, range ambiguities are well known to be a limitation for SAR systems which operates with pulsed transmitted signal. The ambiguous reflected signal corresponding to one pulse is then detected when the radar has already transmitted the next pulse. In this paper, we demonstrate that the range ambiguity mitigation is possible by using orthogonal transmitted wave as OFDM pulses. The coded OFDM signal is optimized through genetic optimization procedures based on radar image quality parameters. Moreover, we propose to design a multiple-input multiple-output (MIMO) configuration to enhance the noise robustness of a radar system and this configuration is mainly efficient in the case of using orthogonal waves as OFDM pulses. The results we obtain show that OFDM signals outperform conventional radar chirps for range ambiguity suppression and for robustness enhancement in 2 ×2 MIMO configuration.

Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells

PubMed Central

Liu, Yuhang; Zhao, Jingbo; Li, Zhengke; Mu, Cheng; Hu, Huawei; Jiang, Kui; Lin, Haoran; Ade, Harald; Yan, He

2014-01-01

Although the field of polymer solar cell has seen much progress in device performance in the past few years, several limitations are holding back its further development. For instance, current high-efficiency (>9.0%) cells are restricted to material combinations that are based on limited donor polymers and only one specific fullerene acceptor. Here we report the achievement of high-performance (efficiencies up to 10.8%, fill factors up to 77%) thick-film polymer solar cells for multiple polymer:fullerene combinations via the formation of a near-ideal polymer:fullerene morphology that contains highly crystalline yet reasonably small polymer domains. This morphology is controlled by the temperature-dependent aggregation behaviour of the donor polymers and is insensitive to the choice of fullerenes. The uncovered aggregation and design rules yield three high-efficiency (>10%) donor polymers and will allow further synthetic advances and matching of both the polymer and fullerene materials, potentially leading to significantly improved performance and increased design flexibility. PMID:25382026

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.

Overview: The Design, Adoption, and Analysis of a Visual Document Mining Tool for Investigative Journalists.

PubMed

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.

Spatially Common Sparsity Based Adaptive Channel Estimation and Feedback for FDD Massive MIMO

NASA Astrophysics Data System (ADS)

Gao, Zhen; Dai, Linglong; Wang, Zhaocheng; Chen, Sheng

2015-12-01

This paper proposes a spatially common sparsity based adaptive channel estimation and feedback scheme for frequency division duplex based massive multi-input multi-output (MIMO) systems, which adapts training overhead and pilot design to reliably estimate and feed back the downlink channel state information (CSI) with significantly reduced overhead. Specifically, a non-orthogonal downlink pilot design is first proposed, which is very different from standard orthogonal pilots. By exploiting the spatially common sparsity of massive MIMO channels, a compressive sensing (CS) based adaptive CSI acquisition scheme is proposed, where the consumed time slot overhead only adaptively depends on the sparsity level of the channels. Additionally, a distributed sparsity adaptive matching pursuit algorithm is proposed to jointly estimate the channels of multiple subcarriers. Furthermore, by exploiting the temporal channel correlation, a closed-loop channel tracking scheme is provided, which adaptively designs the non-orthogonal pilot according to the previous channel estimation to achieve an enhanced CSI acquisition. Finally, we generalize the results of the multiple-measurement-vectors case in CS and derive the Cramer-Rao lower bound of the proposed scheme, which enlightens us to design the non-orthogonal pilot signals for the improved performance. Simulation results demonstrate that the proposed scheme outperforms its counterparts, and it is capable of approaching the performance bound.

Extended target recognition in cognitive radar networks.

PubMed

Wei, Yimin; Meng, Huadong; Liu, Yimin; Wang, Xiqin

2010-01-01

We address the problem of adaptive waveform design for extended target recognition in cognitive radar networks. A closed-loop active target recognition radar system is extended to the case of a centralized cognitive radar network, in which a generalized likelihood ratio (GLR) based sequential hypothesis testing (SHT) framework is employed. Using Doppler velocities measured by multiple radars, the target aspect angle for each radar is calculated. The joint probability of each target hypothesis is then updated using observations from different radar line of sights (LOS). Based on these probabilities, a minimum correlation algorithm is proposed to adaptively design the transmit waveform for each radar in an amplitude fluctuation situation. Simulation results demonstrate performance improvements due to the cognitive radar network and adaptive waveform design. Our minimum correlation algorithm outperforms the eigen-waveform solution and other non-cognitive waveform design approaches.

Building evaluation capacity in Ontario's public health units: promising practices and strategies.

PubMed

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.

Optimal knockout strategies in genome-scale metabolic networks using particle swarm optimization.

PubMed

Nair, Govind; Jungreuthmayer, Christian; Zanghellini, Jürgen

2017-02-01

Knockout strategies, particularly the concept of constrained minimal cut sets (cMCSs), are an important part of the arsenal of tools used in manipulating metabolic networks. Given a specific design, cMCSs can be calculated even in genome-scale networks. We would however like to find not only the optimal intervention strategy for a given design but the best possible design too. Our solution (PSOMCS) is to use particle swarm optimization (PSO) along with the direct calculation of cMCSs from the stoichiometric matrix to obtain optimal designs satisfying multiple objectives. To illustrate the working of PSOMCS, we apply it to a toy network. Next we show its superiority by comparing its performance against other comparable methods on a medium sized E. coli core metabolic network. PSOMCS not only finds solutions comparable to previously published results but also it is orders of magnitude faster. Finally, we use PSOMCS to predict knockouts satisfying multiple objectives in a genome-scale metabolic model of E. coli and compare it with OptKnock and RobustKnock. PSOMCS finds competitive knockout strategies and designs compared to other current methods and is in some cases significantly faster. It can be used in identifying knockouts which will force optimal desired behaviors in large and genome scale metabolic networks. It will be even more useful as larger metabolic models of industrially relevant organisms become available.

Sensitizing Carbon Nanotube Transistors for Single Molecule Sensor Applications

NASA Astrophysics Data System (ADS)

Collins, Philip G.; Akhterov, Maxim; Sims, Patrick C.; Fuller, Elliot J.; Gul, O. Tolga; Pan, Deng

2015-03-01

Recent work has demonstrated single-charge sensitivity in two types of carbon nanotube transistors. In one case, a two-level system near the nanotube or noncovalently attached to the nanotube perturbs the current electrostatically. In a second case, a sidewall defect or other covalent modification sensitizes one site along the conductor. Comparative research has helped reveal differences in the transduction mechanisms of the two cases and provides design rules for maximizing reliable signals for sensing applications. The covalent modifications are not mere perturbations and they are far more sensitive than noncovalent attachments, for example. However, the new degrees of freedom that accompany covalent disorder often have similar energy scales, leading to multiple independent fluctuations that degrade the overall signal-to-noise. Noncovalent sensitization generally produces a smaller signal amplitude in a background of other low-energy fluctuators, but a well-designed noncovalent linker can result in a highly predictable signal amplitudes. Furthermore, noncovalent fabrication methods are scalable, so that wafer-scale arrays of molecular sensors are most likely to follow this path. This work was supported by NSF (ECCS-1231910).

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.

A simulation-based probabilistic design method for arctic sea transport systems

NASA Astrophysics Data System (ADS)

Martin, Bergström; Ove, Erikstad Stein; Sören, Ehlers

2016-12-01

When designing an arctic cargo ship, it is necessary to consider multiple stochastic factors. This paper evaluates the merits of a simulation-based probabilistic design method specifically developed to deal with this challenge. The outcome of the paper indicates that the incorporation of simulations and probabilistic design parameters into the design process enables more informed design decisions. For instance, it enables the assessment of the stochastic transport capacity of an arctic ship, as well as of its long-term ice exposure that can be used to determine an appropriate level of ice-strengthening. The outcome of the paper also indicates that significant gains in transport system cost-efficiency can be obtained by extending the boundaries of the design task beyond the individual vessel. In the case of industrial shipping, this allows for instance the consideration of port-based cargo storage facilities allowing for temporary shortages in transport capacity and thus a reduction in the required fleet size / ship capacity.

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.

Tools for Designing and Analyzing Structures

NASA Technical Reports Server (NTRS)

Luz, Paul L.

2005-01-01

Structural Design and Analysis Toolset is a collection of approximately 26 Microsoft Excel spreadsheet programs, each of which performs calculations within a different subdiscipline of structural design and analysis. These programs present input and output data in user-friendly, menu-driven formats. Although these programs cannot solve complex cases like those treated by larger finite element codes, these programs do yield quick solutions to numerous common problems more rapidly than the finite element codes, thereby making it possible to quickly perform multiple preliminary analyses - e.g., to establish approximate limits prior to detailed analyses by the larger finite element codes. These programs perform different types of calculations, as follows: 1. determination of geometric properties for a variety of standard structural components; 2. analysis of static, vibrational, and thermal- gradient loads and deflections in certain structures (mostly beams and, in the case of thermal-gradients, mirrors); 3. kinetic energies of fans; 4. detailed analysis of stress and buckling in beams, plates, columns, and a variety of shell structures; and 5. temperature dependent properties of materials, including figures of merit that characterize strength, stiffness, and deformation response to thermal gradients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mankamo, T.; Kim, I.S.; Yang, Ji Wu

Failures in the auxiliary feedwater (AFW) system of pressurized water reactors (PWRs) are considered to involve substantial risk whether a decision is made to either continue power operation while repair is being done, or to shut down the plant to undertake repairs. Technical specification action requirements usually require immediate plant shutdown in the case of multiple failures in the system (in some cases, immediate repair of one train is required when all AFW trains fail). This paper presents a probabilistic risk assessment-based method to quantitatively evaluate and compare both the risks of continued power operation and of shutting the plantmore » down, given known failures in the system. The method is applied to the AFW system for four different PWRs. Results show that the risk of continued power operation and plant shutdown both are substantial, but the latter is larger than the former over the usual repair time. This was proven for four plants with different designs: two operating Westinghouse plants, one operating Asea-Brown Boveri Combustion Engineering Plant, and one of evolutionary design. The method can be used to analyze individual plant design and to improve AFW action requirements using risk-informed evaluations.« less

A rare case of multiple schwannomas presenting with scrotal mass: a probable case of schwannomatosis.

PubMed

Ikari, Ryo; Okamoto, Keisei; Yoshida, Tetsuya; Johnin, Kazuyoshi; Okabe, Hidetoshi; Okada, Yusaku

2010-08-01

We report a rare case of multiple schwannomas presenting with scrotal mass. In the present case, a scrotal schwannoma developed in a 66-year-old man with a history of brain tumor surgery. Investigating the patient's past history lead to the diagnosis as probable schwannomatosis. Patients with schwannomatosis are at increased risk of developing multiple schwannomas and these patients need regular surveillance. In this regard, the present case highlights the importance of thorough history taking in patients with scrotal schwannoma.

Visually Exploring Transportation Schedules.

PubMed

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.

Modular, multi-level groundwater sampler

DOEpatents

Nichols, Ralph L.; Widdowson, Mark A.; Mullinex, Harry; Orne, William H.; Looney, Brian B.

1994-01-01

Apparatus for taking a multiple of samples of groundwater or pressure measurements from a well simultaneously. The apparatus comprises a series of chambers arranged in an axial array, each of which is dimensioned to fit into a perforated well casing and leave a small gap between the well casing and the exterior of the chamber. Seals at each end of the container define the limits to the axial portion of the well to be sampled. A submersible pump in each chamber pumps the groundwater that passes through the well casing perforations into the gap from the gap to the surface for analysis. The power lines and hoses for the chambers farther down the array pass through each chamber above them in the array. The seals are solid, water-proof, non-reactive, resilient disks supported to engage the inside surface of the well casing. Because of the modular design, the apparatus provides flexibility for use in a variety of well configurations.

Multiobjective optimisation design for enterprise system operation in the case of scheduling problem with deteriorating jobs

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.

Visual Analysis of MOOC Forums with iForum.

PubMed

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.

The portfolio approach to competency-based assessment at the Cleveland Clinic Lerner College of Medicine.

PubMed

Dannefer, Elaine F; Henson, Lindsey C

2007-05-01

Despite the rapid expansion of interest in competency-based assessment, few descriptions of assessment systems specifically designed for a competency-based curriculum have been reported. The purpose of this article is to describe the design of a portfolio approach to a comprehensive, competency-based assessment system that is fully integrated with the curriculum to foster an educational environment focused on learning. The educational design goal of the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University was to create an integrated educational program-curriculum and instructional methods, student assessment processes, and learning environment-to prepare medical students for success in careers as physician investigators. The first class in the five-year program matriculated in 2004. To graduate, a student must demonstrate mastery of nine competencies: research, medical knowledge, communication, professionalism, clinical skills, clinical reasoning, health care systems, personal development, and reflective practice. The portfolio provides a tool for collecting and managing multiple types of assessment evidence from multiple contexts and sources within the curriculum to document competence and promote reflective practice skills. This article describes how the portfolio was developed to provide both formative and summative assessment of student achievement in relation to the program's nine competencies.

Dynamic load mitigation using dissipative elastic metamaterials with multiple Maxwell-type oscillators

NASA Astrophysics Data System (ADS)

Alamri, Sagr; Li, Bing; Tan, K. T.

2018-03-01

Dissipative elastic metamaterials have attracted increased attention in recent times. This paper presents the development of a dissipative elastic metamaterial with multiple Maxwell-type resonators for stress wave attenuation. The mechanism of the dissipation effect on the vibration characteristics is systematically investigated by mass-spring-damper models with single and dual resonators. Based on the parameter optimization, it is revealed that a broadband wave attenuation region (stopping band) can be obtained by properly utilizing interactions from resonant motions and viscoelastic effects of the Maxwell-type oscillators. The relevant numerical verifications are conducted for various cases, and excellent agreement between the numerical and theoretical frequency response functions is shown. The design of this dissipative metamaterial system is further applied for dynamic load mitigation and blast wave attenuation. Moreover, the transient response in the continuum model is designed and analyzed for more robust design. By virtue of the bandgap merging effect induced by the Maxwell-type damper, the transient blast wave can be almost completely suppressed in the low frequency range. A significantly improved performance of the proposed dissipative metamaterials for stress wave mitigation is verified in both time and frequency domains.

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.

Multiple orthokeratinized odontogenic cysts: a case report.

PubMed

Cheng, Yi-Shing Lisa; Liang, Hui; Wright, John; Teenier, Tom

2015-03-01

The purpose of this report is to document the clinical, radiographic, pathological and molecular findings of the first case of multiple orthokeratinized odontogenic cysts (OOCs). Multiple odontogenic keratocysts are one of the major features of nevoid basal cell carcinoma syndrome (NBCCS), and loss of heterozygosity in the PTCH gene, the culprit gene for NBCCS, has recently been found in sporadic OOC cases. Therefore, in this presenting case, we also investigated the possibility that this patient might also have NBCCS, by comparing the available clinical information and the molecular findings of this case to the diagnostic criteria for NBCCS (as proposed by the First International Colloquium on NBCCS in 2011). However, this patient with multiple OOCs showed no evidence of having NBCCS. This conclusion supports the findings from previous case series based on sporadic cases that OOC does not appear to be associated with NBCCS.

Tuning Parameters in Heuristics by Using Design of Experiments Methods

NASA Technical Reports Server (NTRS)

Arin, Arif; Rabadi, Ghaith; Unal, Resit

2010-01-01

With the growing complexity of today's large scale problems, it has become more difficult to find optimal solutions by using exact mathematical methods. The need to find near-optimal solutions in an acceptable time frame requires heuristic approaches. In many cases, however, most heuristics have several parameters that need to be "tuned" before they can reach good results. The problem then turns into "finding best parameter setting" for the heuristics to solve the problems efficiently and timely. One-Factor-At-a-Time (OFAT) approach for parameter tuning neglects the interactions between parameters. Design of Experiments (DOE) tools can be instead employed to tune the parameters more effectively. In this paper, we seek the best parameter setting for a Genetic Algorithm (GA) to solve the single machine total weighted tardiness problem in which n jobs must be scheduled on a single machine without preemption, and the objective is to minimize the total weighted tardiness. Benchmark instances for the problem are available in the literature. To fine tune the GA parameters in the most efficient way, we compare multiple DOE models including 2-level (2k ) full factorial design, orthogonal array design, central composite design, D-optimal design and signal-to-noise (SIN) ratios. In each DOE method, a mathematical model is created using regression analysis, and solved to obtain the best parameter setting. After verification runs using the tuned parameter setting, the preliminary results for optimal solutions of multiple instances were found efficiently.

VAUD: A Visual Analysis Approach for Exploring Spatio-Temporal Urban Data.

PubMed

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.

A novel biasing dependent circuit model of resonant cavity enhanced avalanche photodetectors (RCE-APDs)

NASA Astrophysics Data System (ADS)

Abdelhamid, Mostafa R.; El-Batawy, Yasser M.; Deen, M. Jamal

2018-02-01

In Resonant Cavity Enhanced Photodetectors (RCE-PDs), the trade-off between the bandwidth and the quantum efficiency in the conventional photodetectors is overcome. In RCE-PDs, large bandwidth can be achieved using a thin absorption layer while the use of a resonant cavity allows for multiple passes of light in the absorption which boosts the quantum efficiency. In this paper, a complete bias-dependent model for the Resonant Cavity Enhanced-Separated Absorption Graded Charge Multiplication-Avalanche Photodetector (RCE-SAGCM-APD) is presented. The proposed model takes into account the case of drift velocities other than the saturation velocity, thus modeling this effect on the photodetector different design parameters such as Gain, Bandwidth and Gain-Bandwidth product.

PIV measurements of airflow past multiple cylinders

NASA Astrophysics Data System (ADS)

Wodziak, Waldemar; Sobczyk, Jacek

2018-06-01

Flow characteristics in vicinity of six circular cylinders aligned inline was investigated experimentally by means of PIV method. Experiments were conducted in a low speed closed circuit wind tunnel. Inflow velocity was 1.2 m/s which corresponds to Re=1600 based on the cylinder diameter. Spacing ratio between cylinders L/D was 1.5. Instantaneous and averaged velocity fields were presented. Experiments were designed in order to use their results as a test case for future numerical calculations.

Incorporation of Outcome-Based Contract Requirements in a Real Options Approach for Maintenance Planning

DTIC Science & Technology

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

Deployment Area Selection and Land Withdrawal/Acquisition. M-X/MPS (M-X/Multiple Protective Shelter) Environmental Technical Report. Power and Energy.

DTIC Science & Technology

1981-10-02

acceptable levels under the worst case condition of coal firing. The flue gas desulfurization system would be designed to reduce the sulfer dioxide content...approaches taken. There exists federal statutory authority to implement gas rationing under certain conditions. Thus, federal controls on oil production...such as air quality deterioration, water consumption, P wastewater generation, disposal of flue gas scrubbing sludge, and ash. Another alternative is

Multiple primary Ewing’s sarcomas in cerebral cranium of a child: a case report and review of the literature

PubMed Central

Wang, Dawei; Guo, Zongze

2015-01-01

Ewing’s sarcoma is the second most common pediatric bone tumor. Primary Ewing’s sarcoma occurring in the cerebral cranium is exceptionally rare, with only one reported case of multiple tumor lesions in adolescence to date. We report a case of a 5-year-old male patient with multiple primary Ewing’s sarcomas associated with the cranial bones, the first pediatric case report to date. We also review 71 cases Ewing’s sarcoma involving intracranial extension. The purpose of this article is to provide data concerning the clinical and therapeutic course of multiple primary Ewing’s sarcomas in associated with cerebral cranium. PMID:26261672

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.

PrimerDesign-M: A multiple-alignment based multiple-primer design tool for walking across variable genomes

DOE PAGES

Yoon, Hyejin; Leitner, Thomas

2014-12-17

Analyses of entire viral genomes or mtDNA requires comprehensive design of many primers across their genomes. In addition, simultaneous optimization of several DNA primer design criteria may improve overall experimental efficiency and downstream bioinformatic processing. To achieve these goals, we developed PrimerDesign-M. It includes several options for multiple-primer design, allowing researchers to efficiently design walking primers that cover long DNA targets, such as entire HIV-1 genomes, and that optimizes primers simultaneously informed by genetic diversity in multiple alignments and experimental design constraints given by the user. PrimerDesign-M can also design primers that include DNA barcodes and minimize primer dimerization. PrimerDesign-Mmore » finds optimal primers for highly variable DNA targets and facilitates design flexibility by suggesting alternative designs to adapt to experimental conditions.« less

Male gender and smoking are related to single, but not to multiple, human aortic aneurysms.

PubMed

Gutierrez, Paulo S; Leite, Thiago N P; Mangione, Fernanda M

2015-01-01

There is scanty information concerning multiple aortic aneurysms. Thus, we verified if clinical or pathological characteristics are different in patients with multiple (two or more) aortic aneurysms in comparison with those with only one. We selected at the necropsy files of the Heart Institute, São Paulo University School of Medicine, the last 100 cases with aortic aneurysms, comparing between the two groups: sex, age, presence of systemic arterial hypertension, diabetes, dyslipedemia, history of smoking habit, cause of the aneurysm, cause of death, and if the diagnosis was reached during life. Age was analysed by Mann-Whitney test, and the other variables by chi-square or Fisher's exact test. Multiple aneurysms corresponded to 14% of cases. The proportion of women among patients with multiple aneurysms was higher than among those with single aneurysm (64.3% versus 20.9%, P<.01), even if only cases with atherosclerosis were taken into consideration (women among multiple-6/10, 60.0%; among single-14/70, 20.0%; P=.01). Smoking was less reported in cases with multiple (4/14, 28.6%) than with single aneurysm (53/86, 61.6%; P=.04); considering cases with atherosclerosis, such difference decreases (40.0% of multiple versus 68.6% of single, P=.09). although atherosclerosis is present in most cases of both single and multiple aortic aneurysms, male gender and smoking, considered highly influential in such lesions, are less frequent in patients with multiple than in patients with single aneurysms. Thus mechanisms underlying multiple aortic aneurysms are probably different from those related to single, more common aneurysms. Copyright © 2015 Elsevier Inc. All rights reserved.

Three Hypothetical Inflammation Pathobiology Phenotypes and Pediatric Sepsis-Induced Multiple Organ Failure Outcome.

PubMed

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.

Implementing Distributed Operations: A Comparison of Two Deep Space Missions

NASA Technical Reports Server (NTRS)

Mishkin, Andrew; Larsen, Barbara

2006-01-01

Two very different deep space exploration missions--Mars Exploration Rover and Cassini--have made use of distributed operations for their science teams. In the case of MER, the distributed operations capability was implemented only after the prime mission was completed, as the rovers continued to operate well in excess of their expected mission lifetimes; Cassini, designed for a mission of more than ten years, had planned for distributed operations from its inception. The rapid command turnaround timeline of MER, as well as many of the operations features implemented to support it, have proven to be conducive to distributed operations. These features include: a single science team leader during the tactical operations timeline, highly integrated science and engineering teams, processes and file structures designed to permit multiple team members to work in parallel to deliver sequencing products, web-based spacecraft status and planning reports for team-wide access, and near-elimination of paper products from the operations process. Additionally, MER has benefited from the initial co-location of its entire operations team, and from having a single Principal Investigator, while Cassini operations have had to reconcile multiple science teams distributed from before launch. Cassini has faced greater challenges in implementing effective distributed operations. Because extensive early planning is required to capture science opportunities on its tour and because sequence development takes significantly longer than sequence execution, multiple teams are contributing to multiple sequences concurrently. The complexity of integrating inputs from multiple teams is exacerbated by spacecraft operability issues and resource contention among the teams, each of which has their own Principal Investigator. Finally, much of the technology that MER has exploited to facilitate distributed operations was not available when the Cassini ground system was designed, although later adoption of web-based and telecommunication tools has been critical to the success of Cassini operations.

Automated design of gravity-assist trajectories to Mars and the outer planets

NASA Technical Reports Server (NTRS)

Longuski, James M.; Williams, Steve N.

1991-01-01

In this paper, a new approach to planetary mission design is described which automates the search for gravity-assist trajectories. This method finds all conic solutions given a range of launch dates, a range of launch energies and a set of target planets. The new design tool is applied to the problems of finding multiple encounter trajectories to the outer planets and Venus gravity-assist trajectories to Mars. The last four-planet grand tour opportunity (until the year 2153) is identified. It requires an earth launch in 1996 and encounters Jupiter, Uranus, Neptune, and Pluto. Venus gravity-assist trajectories to Mars for the 30 year period 1995-2024 are examined. It is shown that in many cases these trajectories require less launch energy to reach Mars than direct ballistic trajectories.

10 CFR Appendix N to Part 52 - Standardization of Nuclear Power Plant Designs: Combined Licenses To Construct and Operate...

Code of Federal Regulations, 2011 CFR

2011-01-01

... Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple Sites N Appendix N... Designs: Combined Licenses To Construct and Operate Nuclear Power Reactors of Identical Design at Multiple... construct and operate nuclear power reactors of identical design (“common design”) to be located at multiple...

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.

Multiple magnet ingestion: is there a role for early surgical intervention?

PubMed

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.

Using public control genotype data to increase power and decrease cost of case-control genetic association studies.

PubMed

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.

Improved Aerogel Vacuum Thermal Insulation

NASA Technical Reports Server (NTRS)

Ruemmele, Warren P.; Bue, Grant C.

2009-01-01

An improved design concept for aerogel vacuum thermal-insulation panels calls for multiple layers of aerogel sandwiched between layers of aluminized Mylar (or equivalent) poly(ethylene terephthalate), as depicted in the figure. This concept is applicable to both the rigid (brick) form and the flexible (blanket) form of aerogel vacuum thermal-insulation panels. Heretofore, the fabrication of a typical aerogel vacuum insulating panel has involved encapsulation of a single layer of aerogel in poly(ethylene terephthalate) and pumping of gases out of the aerogel-filled volume. A multilayer panel according to the improved design concept is fabricated in basically the same way: Multiple alternating layers of aerogel and aluminized poly(ethylene terephthalate) are assembled, then encapsulated in an outer layer of poly(ethylene terephthalate), and then the volume containing the multilayer structure is evacuated as in the single-layer case. The multilayer concept makes it possible to reduce effective thermal conductivity of a panel below that of a comparable single-layer panel, without adding weight or incurring other performance penalties. Implementation of the multilayer concept is simple and relatively inexpensive, involving only a few additional fabrication steps to assemble the multiple layers prior to evacuation. For a panel of the blanket type, the multilayer concept, affords the additional advantage of reduced stiffness.

Sampling design considerations for demographic studies: a case of colonial seabirds

USGS Publications Warehouse

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.

Proof of principle for epitope-focused vaccine design

PubMed Central

Correia, Bruno E.; Bates, John T.; Loomis, Rebecca J.; Baneyx, Gretchen; Carrico, Christopher; Jardine, Joseph G.; Rupert, Peter; Correnti, Colin; Kalyuzhniy, Oleksandr; Vittal, Vinayak; Connell, Mary J.; Stevens, Eric; Schroeter, Alexandria; Chen, Man; MacPherson, Skye; Serra, Andreia M.; Adachi, Yumiko; Holmes, Margaret A.; Li, Yuxing; Klevit, Rachel E.; Graham, Barney S.; Wyatt, Richard T.; Baker, David; Strong, Roland K.; Crowe, James E.; Johnson, Philip R.; Schief, William R.

2014-01-01

Summary Vaccines prevent infectious disease largely by inducing protective neutralizing antibodies against vulnerable epitopes. Multiple major pathogens have resisted traditional vaccine development, although vulnerable epitopes targeted by neutralizing antibodies have been identified for several such cases. Hence, new vaccine design methods to induce epitope-specific neutralizing antibodies are needed. Here we show, with a neutralization epitope from respiratory syncytial virus (RSV), that computational protein design can generate small, thermally and conformationally stable protein scaffolds that accurately mimic the viral epitope structure and induce potent neutralizing antibodies. These scaffolds represent promising leads for research and development of a human RSV vaccine needed to protect infants, young children and the elderly. More generally, the results provide proof of principle for epitope-focused and scaffold-based vaccine design, and encourage the evaluation and further development of these strategies for a variety of other vaccine targets including antigenically highly variable pathogens such as HIV and influenza. PMID:24499818

A VLSI implementation of DCT using pass transistor technology

NASA Technical Reports Server (NTRS)

Kamath, S.; Lynn, Douglas; Whitaker, Sterling

1992-01-01

A VLSI design for performing the Discrete Cosine Transform (DCT) operation on image blocks of size 16 x 16 in a real time fashion operating at 34 MHz (worst case) is presented. The process used was Hewlett-Packard's CMOS26--A 3 metal CMOS process with a minimum feature size of 0.75 micron. The design is based on Multiply-Accumulate (MAC) cells which make use of a modified Booth recoding algorithm for performing multiplication. The design of these cells is straight forward, and the layouts are regular with no complex routing. Two versions of these MAC cells were designed and their layouts completed. Both versions were simulated using SPICE to estimate their performance. One version is slightly faster at the cost of larger silicon area and higher power consumption. An improvement in speed of almost 20 percent is achieved after several iterations of simulation and re-sizing.

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

Pediatric emotional dysregulation and behavioral disruptiveness treated with hypnosis: a time-series design.

PubMed

Iglesias, Alex; Iglesias, Adam

2014-01-01

A case of pediatric oppositional defiant disorder (ODD) with concomitant emotional dysregulation and secondary behavioral disruptiveness was treated with hypnosis by means of the hypnotic hold, a method adapted by the authors. An A-B-A-B time-series design with multiple replications was employed to measure the relationship of the hypnotic treatment to the dependent measure: episodes of emotional dysregulation with accompanying behavioral disruptiveness. The findings indicated a statistically significant relationship between the degree of change from phase to phase and the treatment. Follow-up at 6 months indicated a significant reduction of the frequency of targeted episodes of emotional dysregulation and behavioral disruptiveness at home.

Modifiable Neighborhood Features Associated With Adolescent Homicide

PubMed Central

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

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.

Use of synthesized data to support complex ad-hoc queries in an enterprise information warehouse: a diabetes use case.

PubMed

Rogers, Patrick; Erdal, Selnur; Santangelo, Jennifer; Liu, Jianhua; Schuster, Dara; Kamal, Jyoti

2008-11-06

The Ohio State University Medical Center (OSUMC) Information Warehouse (IW) is a comprehensive data warehousing facility incorporating operational, clinical, and biological data sets from multiple enterprise system. It is common for users of the IW to request complex ad-hoc queries that often require significant intervention by data analyst. In response to this challenge, we have designed a workflow that leverages synthesized data elements to support such queries in an more timely, efficient manner.

Spacecraft Trajectory Analysis and Mission Planning Simulation (STAMPS) Software

NASA Technical Reports Server (NTRS)

Puckett, Nancy; Pettinger, Kris; Hallstrom,John; Brownfield, Dana; Blinn, Eric; Williams, Frank; Wiuff, Kelli; McCarty, Steve; Ramirez, Daniel; Lamotte, Nicole;

Video-Based Intervention in Teaching Fraction Problem-Solving to Students with Autism Spectrum Disorder.

PubMed

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.

Polyarteritis nodosa: MDCT as a 'One-Stop Shop' Modality for Whole-Body Arterial Evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsai, W.-L.; Tsai, I-C.; Lee Tain, E-mail: s841082@ym.edu.t

Polyarteritis nodosa is a rare disease, which is characterized by aneurysm formation and occlusion in the arteries of multiple systems. Due to its extensive involvement, whole-body evaluation is necessary for diagnosis and treatment monitoring. We report a case of polyarteritis nodosa using multidetector-row computed tomography (MDCT) as a 'one-stop shop' modality for whole-body arterial evaluation. With precise protocol design, MDCT can be used as a reliable noninvasive modality providing comprehensive whole-body arterial evaluation.

[Application of damage control concept in severe limbs fractures combining with multiple trauma].

PubMed

Bayin, Er-gu-le; Jin, Hong-bing; Li, Ming

2015-09-01

To discuss the application and clinical effect of damage control concept in the treatment of severe limbs fractures combining with multiple trauma. From July 2009 to July 2012, 30 patients with severe limbs fractures combining with multiple trauma were treated with the damage control concept, included 20 males and 10 females with an average age of (34.03 ± 12.81) years old ranging from 20 to 60 years old; the ISS averaged (35.00 ± 12.81) points (ranged from 26 to 54 points). And the control group also contained 30 patients with severe limbs fractures combining with multiple trauma treated by the traditional operation from June 2006 to June 2009, there were 23 males and 7 females with an average age of (34.23 ± 11.04) years old ranging from 18 to 65 years old. The ISS averaged (35.56 ± 11.04) points (ranged from 26 to 51 points). The age, gender, ISS, Gustilo classification, operation time, intraoperative blood loss, blood transfusion,postoperative complications and mortality rate were observed and compared. In the damage control concept group,there were 28 cases surviving and 2 cases (6.7%) death; 6 cases of postoperative complication included 2 cases of adult respiratory distress syndrome, 1 case of multiple organ failure, 1 case of disseminated intravascular coagulation and 2 cases of wound infection. In the control group, there were 22 cases surviving and 8 cases death(26.7%); 13 cases of postoperative complication included 4 cases of adult respiratory distress syndrome,2 cases of multiple organ failure, 2 cases of disseminated intravascular coagulation and 3 cases of wound infection. There were no statistically significant differences between two groups in age, gender, ISS, Gustilo classfication and complication (P > 0.05), however there were statistically significant differences in mortality rate, operation time, blodd loss, blodd transfusion between two groups (P < 0.05). Damage control concept is used to treat severe limbs fractures combining with multiple trauma which has the rapid and effective therapy, can improve survival rate and reduce complication.

A network control theory approach to modeling and optimal control of zoonoses: case study of brucellosis transmission in sub-Saharan Africa.

PubMed

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.

A Network Control Theory Approach to Modeling and Optimal Control of Zoonoses: Case Study of Brucellosis Transmission in Sub-Saharan Africa

PubMed Central

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