NASA Astrophysics Data System (ADS)
Zolfigol, Mohammad Ali; Kiafar, Mahya; Yarie, Meysam; Taherpour, Avat(Arman); Fellowes, Thomas; Nicole Hancok, Amber; Yari, Ako
2017-06-01
Experimental and computational studies in the synthesis of 2-amino-4,6-diphenylnicotinonitrile using HBF4 as an oxidizing promoter catalyst under mild and solvent free conditions were carried out. The suggested anomeric based oxidation (ABO) mechanism is supported by experimental and theoretical evidence. The theoretical study shows that the intermediate isomers with 5R- and 5S- chiral positions have suitable structures for the aromatization through an anomeric based oxidation in the final step of the mechanistic pathway.
Misleading Theoretical Assumptions in Hypertext/Hypermedia Research.
ERIC Educational Resources Information Center
Tergan, Sigmar-Olaf
1997-01-01
Reviews basic theoretical assumptions of research on learning with hypertext/hypermedia. Focuses on whether the results of research on hypertext/hypermedia-based learning support these assumptions. Results of empirical studies and theoretical analysis reveal that many research approaches have been misled by inappropriate theoretical assumptions on…
Physical Violence between Siblings: A Theoretical and Empirical Analysis
ERIC Educational Resources Information Center
Hoffman, Kristi L.; Kiecolt, K. Jill; Edwards, John N.
2005-01-01
This study develops and tests a theoretical model to explain sibling violence based on the feminist, conflict, and social learning theoretical perspectives and research in psychology and sociology. A multivariate analysis of data from 651 young adults generally supports hypotheses from all three theoretical perspectives. Males with brothers have…
A Social-Cognitive Theoretical Framework for Examining Music Teacher Identity
ERIC Educational Resources Information Center
McClellan, Edward
2017-01-01
The purpose of the study was to examine a diverse range of research literature to provide a social-cognitive theoretical framework as a foundation for definition of identity construction in the music teacher education program. The review of literature may reveal a theoretical framework based around tenets of commonly studied constructs in the…
ERIC Educational Resources Information Center
Åsvoll, Håvard
2014-01-01
Within the area of interpretative case studies, there appears to be a vast amount of literature about theoretical interpretations as the main analytical strategy. In light of this theoretically based strategy in case studies, this article presents an extended perspective based on Charles Sanders Peirce's concepts of abduction, deduction and…
Ricks, Samantha L; Alt, Mary
2016-07-01
The purpose of this tutorial is to provide clinicians with a theoretically motivated and evidence-based approach to teaching adjectives to children who struggle with word learning. Given that there are almost no treatment studies to guide this topic, we have synthesized findings from experimental and theoretical literature to come up with a principles-based approach to treatment. We provide a sample lesson plan, incorporating our 3 theoretical principles, and describe the materials chosen and methods used during treatment and assessment. This approach is theoretically motivated, but it needs to be empirically tested.
Study for the dispersion of double-diffraction spectrometers
NASA Astrophysics Data System (ADS)
Pang, Yajun; Zhang, Yinxin; Yang, Huaidong; Huang, Zhanhua; Xu, Mingming; Jin, Guofan
2018-01-01
Double-cascade spectrometers and double-pass spectrometers can be uniformly called double-diffraction spectrometers. In current double-diffraction spectrometers design theory, the differences of the incident angles in the second diffraction are ignored. There is a significant difference between the design in theory and the actual result. In this study, based on the geometries of the double-diffraction spectrometers, we strictly derived the theoretical formulas of their dispersion. By employing the ZEMAX simulation software, verification of our theoretical model is implemented, and the simulation results show big agreement with our theoretical formulas. Based on the conclusions, a double-pass spectrometer was set up and tested, and the experiment results agree with the theoretical model and the simulation.
ERIC Educational Resources Information Center
van Rens, Ger H. M. B.; Lens, Judith A.; de Boer, Michael R.
2006-01-01
Most of the studies of the causes of visual impairment have been population-based studies. These population-based studies provide important information on the incidence and prevalence of "theoretical" eye problems in a community. However, not all those who are visually impaired, from a theoretical point of view, consider themselves as…
Study of network resource allocation based on market and game theoretic mechanism
NASA Astrophysics Data System (ADS)
Liu, Yingmei; Wang, Hongwei; Wang, Gang
2004-04-01
We work on the network resource allocation issue concerning network management system function based on market-oriented mechanism. The scheme is to model the telecommunication network resources as trading goods in which the various network components could be owned by different competitive, real-world entities. This is a multidisciplinary framework concentrating on the similarity between resource allocation in network environment and the market mechanism in economic theory. By taking an economic (market-based and game theoretic) approach in routing of communication network, we study the dynamic behavior under game-theoretic framework in allocating network resources. Based on the prior work of Gibney and Jennings, we apply concepts of utility and fitness to the market mechanism with an intention to close the gap between experiment environment and real world situation.
Enhanced thermoelectric performance of graphene nanoribbon-based devices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hossain, Md Sharafat, E-mail: hossain@student.unimelb.edu.au; Huynh, Duc Hau; Nguyen, Phuong Duc
There have been numerous theoretical studies on exciting thermoelectric properties of graphene nano-ribbons (GNRs); however, most of these studies are mainly based on simulations. In this work, we measure and characterize the thermoelectric properties of GNRs and compare the results with theoretical predictions. Our experimental results verify that nano-structuring and patterning graphene into nano-ribbons significantly enhance its thermoelectric power, confirming previous predictions. Although patterning results in lower conductance (G), the overall power factor (S{sup 2}G) increases for nanoribbons. We demonstrate that edge roughness plays an important role in achieving such an enhanced performance and support it through first principles simulations.more » We show that uncontrolled edge roughness, which is considered detrimental in GNR-based electronic devices, leads to enhanced thermoelectric performance of GNR-based thermoelectric devices. The result validates previously reported theoretical studies of GNRs and demonstrates the potential of GNRs for the realization of highly efficient thermoelectric devices.« less
Qualitative Assessment of Inquiry-Based Teaching Methods
ERIC Educational Resources Information Center
Briggs, Michael; Long, George; Owens, Katrina
2011-01-01
A new approach to teaching method assessment using student focused qualitative studies and the theoretical framework of mental models is proposed. The methodology is considered specifically for the advantages it offers when applied to the assessment of inquiry-based teaching methods. The theoretical foundation of mental models is discussed, and…
Li, Xiaojin; Hu, Xintao; Jin, Changfeng; Han, Junwei; Liu, Tianming; Guo, Lei; Hao, Wei; Li, Lingjiang
2013-01-01
Previous studies have investigated both structural and functional brain networks via graph-theoretical methods. However, there is an important issue that has not been adequately discussed before: what is the optimal theoretical graph model for describing the structural networks of human brain? In this paper, we perform a comparative study to address this problem. Firstly, large-scale cortical regions of interest (ROIs) are localized by recently developed and validated brain reference system named Dense Individualized Common Connectivity-based Cortical Landmarks (DICCCOL) to address the limitations in the identification of the brain network ROIs in previous studies. Then, we construct structural brain networks based on diffusion tensor imaging (DTI) data. Afterwards, the global and local graph properties of the constructed structural brain networks are measured using the state-of-the-art graph analysis algorithms and tools and are further compared with seven popular theoretical graph models. In addition, we compare the topological properties between two graph models, namely, stickiness-index-based model (STICKY) and scale-free gene duplication model (SF-GD), that have higher similarity with the real structural brain networks in terms of global and local graph properties. Our experimental results suggest that among the seven theoretical graph models compared in this study, STICKY and SF-GD models have better performances in characterizing the structural human brain network.
ERIC Educational Resources Information Center
Marasulov, Akhmat; Saipov, Amangeldi; ?rymbayeva, Kulimkhan; Zhiyentayeva, Begaim; Demeuov, Akhan; Konakbaeva, Ulzhamal; Bekbolatova, Akbota
2016-01-01
The aim of the study is to examine the methodological-theoretical construction bases for development mechanism of an integrated model for a specialist's training and teacher's conceptual-theoretical activity. Using the methods of generalization of teaching experience, pedagogical modeling and forecasting, the authors determine the urgent problems…
Methodological, Theoretical, Infrastructural, and Design Issues in Conducting Good Outcome Studies
ERIC Educational Resources Information Center
Kelly, Michael P.; Moore, Tessa A.
2011-01-01
This article outlines a set of methodological, theoretical, and other issues relating to the conduct of good outcome studies. The article begins by considering the contribution of evidence-based medicine to the methodology of outcome research. The lessons which can be applied in outcome studies in nonmedical settings are described. The article…
ERIC Educational Resources Information Center
Donnelly, David S.
2013-01-01
This study employed a design-based research methodology to develop a theoretically sound approach for designing instructional treatments. The instruction of interest addressed the broad issue of physician wellness among medical school faculty, with particular emphasis on physician self-diagnosis and self-care. The theoretically sound approach…
ERIC Educational Resources Information Center
Sadoski, Mark; Willson, Victor L.
2006-01-01
In 1997, Lindamood-Bell Learning Processes partnered with Pueblo School District 60 (PSD60), a heavily minority urban district with many Title I schools, to implement a theoretically based initiative designed to improve Colorado Student Assessment Program reading scores. In this study, the authors examined achievement in Grades 3-5 during the…
Digital Education: Opportunities for Social Collaboration. Digital Education and Learning
ERIC Educational Resources Information Center
Thomas, Michael, Ed.
2011-01-01
This timely collection of theoretical and applied studies examines the pedagogical potential and realities of digital technologies in a wide range of disciplinary contexts across the educational spectrum. By mixing content-based chapters with a theoretical perspective with case studies detailing actual teaching approaches utilizing digital…
Theoretical and experimental characterization of the DUal-BAse transistor (DUBAT)
NASA Astrophysics Data System (ADS)
Wu, Chung-Yu; Wu, Ching-Yuan
1980-11-01
A new A-type integrated voltage controlled differential negative resistance device using an extra effective base region to form a lateral pnp (npn) bipolar transistor beside the original base region of a vertical npn (pnp) bipolar junction transistor, and so called the DUal BAse Transistor (DUBAT), is studied both experimentally and theoretically, The DUBAT has three terminals and is fully comparible with the existing bipolar integrated circuits technologies. Based upon the equivalent circuit of the DUBAT, a simple first-order analytical theory is developed, and important device parameters, such as: the I-V characteristic, the differential negative resistance, and the peak and valley points, are also characterized. One of the proposed integrated structures of the DUBAT, which is similar in structure to I 2L but with similar high density and a normally operated vertical npn transistor, has been successfully fabricated and studied. Comparisons between the experimental data and theoretical analyses are made, and show in satisfactory agreements.
ERIC Educational Resources Information Center
Lephardt, Noreen E.; Lephardt, George P.
A paradigm for learning economic concepts based on cognitive development and learning theory is offered as a guideline for teaching and research. Discussion is divided into two sections. The first section establishes the model's theoretical framework, which is based on two propositions. The first of these is that economic knowledge is not a fixed…
[Theoretical and methodological uses of research in Social and Human Sciences in Health].
Deslandes, Suely Ferreira; Iriart, Jorge Alberto Bernstein
2012-12-01
The current article aims to map and critically reflect on the current theoretical and methodological uses of research in the subfield of social and human sciences in health. A convenience sample was used to select three Brazilian public health journals. Based on a reading of 1,128 abstracts published from 2009 to 2010, 266 articles were selected that presented the empirical base of research stemming from social and human sciences in health. The sample was classified thematically as "theoretical/ methodological reference", "study type/ methodological design", "analytical categories", "data production techniques", and "analytical procedures". We analyze the sample's emic categories, drawing on the authors' literal statements. All the classifications and respective variables were tabulated in Excel. Most of the articles were self-described as qualitative and used more than one data production technique. There was a wide variety of theoretical references, in contrast with the almost total predominance of a single type of data analysis (content analysis). In several cases, important gaps were identified in expounding the study methodology and instrumental use of the qualitative research techniques and methods. However, the review did highlight some new objects of study and innovations in theoretical and methodological approaches.
Making a Traditional Study-Abroad Program Geographic: A Theoretically Informed Regional Approach
ERIC Educational Resources Information Center
Jokisch, Brad
2009-01-01
Geographers have been active in numerous focused study-abroad programs, but few have created or led language-based programs overseas. This article describes the development of a Spanish language program in Ecuador and how it was made geographic primarily through a theoretically informed regional geography course. The approach employs theoretical…
Sujic, R; Gignac, M A; Cockerill, R; Beaton, D E
2011-08-01
The purpose of this literature review is to determine whether and to what extent current post-fracture osteoporosis interventions utilize theories of health behaviour change and whether those that are theory-based are more successful in producing desired behaviour changes. Studies were identified by applying additional criteria to the final selection stage of a systematic review of non-surgical osteoporosis interventions in the orthopaedic environment. We identified 42 primary studies targeted at patients and improving post-fracture osteoporosis care. As well as describing the studies (in terms of design, population, interventions, outcomes), we focused on theoretical framework and elements of behaviour change models. The 42 studies included in this review utilized a variety of post-fracture interventions; however, none of them reported using an underlying theoretical base. Only three studies drew on what we felt to be elements of a theoretical framework. The lack of theoretically based studies points to a currently under-utilized area of behaviour change research that could be applied to post-fracture interventions in order to make them more effective. Despite an abundance of literature supporting theories of behaviour change, post-fracture osteoporosis interventions do not report utilizing these theories. Theories of behaviour change could be applied to post-fracture osteoporosis interventions to explain why patients initiate osteoporosis management. Future research should explore the application of theories of health behaviour change to post-fracture interventions.
Hanbury, Andria; Thompson, Carl; Mannion, Russell
2011-07-01
Tailored implementation strategies targeting health professionals' adoption of evidence-based recommendations are currently being developed. Research has focused on how to select an appropriate theoretical base, how to use that theoretical base to explore the local context, and how to translate theoretical constructs associated with the key factors found to influence innovation adoption into feasible and tailored implementation strategies. The reasons why an intervention is thought not to have worked are often cited as being: inappropriate choice of theoretical base; unsystematic development of the implementation strategies; and a poor evidence base to guide the process. One area of implementation research that is commonly overlooked is how to synthesize the data collected in a local context in order to identify what factors to target with the implementation strategies. This is suggested to be a critical process in the development of a theory-based intervention. The potential of multilevel modelling techniques to synthesize data collected at different hierarchical levels, for example, individual attitudes and team level variables, is discussed. Future research is needed to explore further the potential of multilevel modelling for synthesizing contextual data in implementation studies, as well as techniques for synthesizing qualitative and quantitative data.
The need for international nursing diagnosis research and a theoretical framework.
Lunney, Margaret
2008-01-01
To describe the need for nursing diagnosis research and a theoretical framework for such research. A linguistics theory served as the foundation for the theoretical framework. Reasons for additional nursing diagnosis research are: (a) file names are needed for implementation of electronic health records, (b) international consensus is needed for an international classification, and (c) continuous changes occur in clinical practice. A theoretical framework used by the author is explained. Theoretical frameworks provide support for nursing diagnosis research. Linguistics theory served as an appropriate exemplar theory to support nursing research. Additional nursing diagnosis studies based upon a theoretical framework are needed and linguistics theory can provide an appropriate structure for this research.
ERIC Educational Resources Information Center
Zhu, Wenzhong; Liu, Dan
2014-01-01
Based on a review of the literature on ESP and needs analysis, this paper is intended to offer some theoretical supports and inspirations for BE instructors to develop BE curricula for business contexts. It discusses how the theory of need analysis can be used in Business English curriculum design, and proposes some principles of BE curriculum…
[Private health insurance in Brazil: approaches to public/private patterns in healthcare].
Sestelo, José Antonio de Freitas; Souza, Luis Eugenio Portela Fernandes de; Bahia, Lígia
2013-05-01
This article draws on a previous review of 270 articles on private health plans published from 2000 to 2010 and selects 17 that specifically address the issue of the relationship between the public and private healthcare sectors. Content analysis considered the studies' concepts and terms, related theoretical elements, and predominant lines of argument. A reading of the argumentative strategies detected the existence of a critical view of the modus operandi in the public/private relationship based on Social Medicine and the theoretical tenets of the Brazilian Health Reform Movement. The study also identified contributions based on neoliberal business approaches that focus strictly on economic issues to discuss private health insurance. Understanding the public/private link in healthcare obviously requires the development of a solid empirical base, analyzed with adequate theoretical assumptions due to the inherent degree of complexity in the public/private healthcare interface.
An Exploration of E-Learning Benefits for Saudi Arabia: Toward Policy Reform
ERIC Educational Resources Information Center
Alrashidi, Abdulaziz
2013-01-01
Purpose: The purpose of this study was to examine policies and solutions addressing (a) improving education for citizens of the Kingdom of Saudi Arabia and (b) providing alternative instructional delivery methods, including e-learning for those living in remote areas. Theoretical Framework: The theoretical framework of this study was based on the…
Applying a Conceptual Design Framework to Study Teachers' Use of Educational Technology
ERIC Educational Resources Information Center
Holmberg, Jörgen
2017-01-01
Theoretical outcomes of design-based research (DBR) are often presented in the form of local theory design principles. This article suggests a complementary theoretical construction in DBR, in the form of a "design framework" at a higher abstract level, to study and inform educational design with ICT in different situated contexts.…
NASA Astrophysics Data System (ADS)
Rashidi Moghaddam, M.; Ayatollahi, M. R.; Berto, F.
2018-01-01
The values of mode II fracture toughness reported in the literature for several rocks are studied theoretically by using a modified criterion based on strain energy density averaged over a control volume around the crack tip. The modified criterion takes into account the effect of T-stress in addition to the singular terms of stresses/strains. The experimental results are related to mode II fracture tests performed on the semicircular bend and Brazilian disk specimens. There are good agreements between theoretical predictions using the generalized averaged strain energy density criterion and the experimental results. The theoretical results reveal that the value of mode II fracture toughness is affected by the size of control volume around the crack tip and also the magnitude and sign of T-stress.
Valentijn, Pim P; Bruijnzeels, Marc A; de Leeuw, Rob J; Schrijvers, Guus J.P
2012-01-01
Purpose Capacity problems and political pressures have led to a rapid change in the organization of primary care from mono disciplinary small business to complex inter-organizational relationships. It is assumed that inter-organizational collaboration is the driving force to achieve integrated (primary) care. Despite the importance of collaboration and integration of services in primary care, there is no unambiguous definition for both concepts. The purpose of this study is to examine and link the conceptualisation and validation of the terms inter-organizational collaboration and integrated primary care using a theoretical framework. Theory The theoretical framework is based on the complex collaboration process of negotiation among multiple stakeholder groups in primary care. Methods A literature review of health sciences and business databases, and targeted grey literature sources. Based on the literature review we operationalized the constructs of inter-organizational collaboration and integrated primary care in a theoretical framework. The framework is being validated in an explorative study of 80 primary care projects in the Netherlands. Results and conclusions Integrated primary care is considered as a multidimensional construct based on a continuum of integration, extending from segregation to integration. The synthesis of the current theories and concepts of inter-organizational collaboration is insufficient to deal with the complexity of collaborative issues in primary care. One coherent and integrated theoretical framework was found that could make the complex collaboration process in primary care transparent. This study presented theoretical framework is a first step to understand the patterns of successful collaboration and integration in primary care services. These patterns can give insights in the organization forms needed to create a good working integrated (primary) care system that fits the local needs of a population. Preliminary data of the patterns of collaboration and integration will be presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Y.; Chen, W.F.
1998-08-01
This research was based on a two-part basic research investigation studying the effects of cement paste-aggregate interfaces (or interfacial transition zones-ITZ) on strength and durability of concrete. Part 1 dealt with the theoretical study and Part 2 dealt with the experimental.
Numerical modeling of solar irradiance on earth's surface
NASA Astrophysics Data System (ADS)
Mera, E.; Gutierez, L.; Da Silva, L.; Miranda, E.
2016-05-01
Modeling studies and estimation of solar radiation in base area, touch from the problems of estimating equation of time, distance equation solar space, solar declination, calculation of surface irradiance, considering that there are a lot of studies you reported the inability of these theoretical equations to be accurate estimates of radiation, many authors have proceeded to make corrections through calibrations with Pyranometers field (solarimeters) or the use of satellites, this being very poor technique last because there a differentiation between radiation and radiant kinetic effects. Because of the above and considering that there is a weather station properly calibrated ground in the Susques Salar in the Jujuy Province, Republic of Argentina, proceeded to make the following modeling of the variable in question, it proceeded to perform the following process: 1. Theoretical Modeling, 2. graphic study of the theoretical and actual data, 3. Adjust primary calibration data through data segmentation on an hourly basis, through horizontal and adding asymptotic constant, 4. Analysis of scatter plot and contrast series. Based on the above steps, the modeling data obtained: Step One: Theoretical data were generated, Step Two: The theoretical data moved 5 hours, Step Three: an asymptote of all negative emissivity values applied, Solve Excel algorithm was applied to least squares minimization between actual and modeled values, obtaining new values of asymptotes with the corresponding theoretical reformulation of data. Add a constant value by month, over time range set (4:00 pm to 6:00 pm). Step Four: The modeling equation coefficients had monthly correlation between actual and theoretical data ranging from 0.7 to 0.9.
Kiesewetter, Jan; Fischer, Martin R
2015-01-01
Simulation-based teamwork trainings are considered a powerful training method to advance teamwork, which becomes more relevant in medical education. The measurement of teamwork is of high importance and several instruments have been developed for various medical domains to meet this need. To our knowledge, no theoretically-based and easy-to-use measurement instrument has been published nor developed specifically for simulation-based teamwork trainings of medical students. Internist ward-rounds function as an important example of teamwork in medicine. The purpose of this study was to provide a validated, theoretically-based instrument that is easy-to-use. Furthermore, this study aimed to identify if and when rater scores relate to performance. Based on a theoretical framework for teamwork behaviour, items regarding four teamwork components (Team Coordination, Team Cooperation, Information Exchange, Team Adjustment Behaviours) were developed. In study one, three ward-round scenarios, simulated by 69 students, were videotaped and rated independently by four trained raters. The instrument was tested for the embedded psychometric properties and factorial structure. In study two, the instrument was tested for construct validity with an external criterion with a second set of 100 students and four raters. In study one, the factorial structure matched the theoretical components but was unable to separate Information Exchange and Team Cooperation. The preliminary version showed adequate psychometric properties (Cronbach's α=.75). In study two, the instrument showed physician rater scores were more reliable in measurement than those of student raters. Furthermore, a close correlation between the scale and clinical performance as an external criteria was shown (r=.64) and the sufficient psychometric properties were replicated (Cronbach's α=.78). The validation allows for use of the simulated teamwork assessment scale in undergraduate medical ward-round trainings to reliably measure teamwork by physicians. Further studies are needed to verify the applicability of the instrument.
Kiesewetter, Jan; Fischer, Martin R.
2015-01-01
Background: Simulation-based teamwork trainings are considered a powerful training method to advance teamwork, which becomes more relevant in medical education. The measurement of teamwork is of high importance and several instruments have been developed for various medical domains to meet this need. To our knowledge, no theoretically-based and easy-to-use measurement instrument has been published nor developed specifically for simulation-based teamwork trainings of medical students. Internist ward-rounds function as an important example of teamwork in medicine. Purposes: The purpose of this study was to provide a validated, theoretically-based instrument that is easy-to-use. Furthermore, this study aimed to identify if and when rater scores relate to performance. Methods: Based on a theoretical framework for teamwork behaviour, items regarding four teamwork components (Team Coordination, Team Cooperation, Information Exchange, Team Adjustment Behaviours) were developed. In study one, three ward-round scenarios, simulated by 69 students, were videotaped and rated independently by four trained raters. The instrument was tested for the embedded psychometric properties and factorial structure. In study two, the instrument was tested for construct validity with an external criterion with a second set of 100 students and four raters. Results: In study one, the factorial structure matched the theoretical components but was unable to separate Information Exchange and Team Cooperation. The preliminary version showed adequate psychometric properties (Cronbach’s α=.75). In study two, the instrument showed physician rater scores were more reliable in measurement than those of student raters. Furthermore, a close correlation between the scale and clinical performance as an external criteria was shown (r=.64) and the sufficient psychometric properties were replicated (Cronbach’s α=.78). Conclusions: The validation allows for use of the simulated teamwork assessment scale in undergraduate medical ward-round trainings to reliably measure teamwork by physicians. Further studies are needed to verify the applicability of the instrument. PMID:26038684
Francis, Jill J; Stockton, Charlotte; Eccles, Martin P; Johnston, Marie; Cuthbertson, Brian H; Grimshaw, Jeremy M; Hyde, Chris; Tinmouth, Alan; Stanworth, Simon J
2009-11-01
Many theories of behaviour are potentially relevant to predictive and intervention studies but most studies investigate a narrow range of theories. Michie et al. (2005) agreed 12 'theoretical domains' from 33 theories that explain behaviour change. They developed a 'Theoretical Domains Interview' (TDI) for identifying relevant domains for specific clinical behaviours, but the framework has not been used for selecting theories for predictive studies. It was used here to investigate clinicians' transfusion behaviour in intensive care units (ICU). Evidence suggests that red blood cells transfusion could be reduced for some patients without reducing quality of care. (1) To identify the domains relevant to transfusion practice in ICUs and neonatal intensive care units (NICUs), using the TDI. (2) To use the identified domains to select appropriate theories for a study predicting transfusion behaviour. An adapted TDI about managing a patient with borderline haemoglobin by watching and waiting instead of transfusing red blood cells was used to conduct semi-structured, one-to-one interviews with 18 intensive care consultants and neonatologists across the UK. Relevant theoretical domains were: knowledge, beliefs about capabilities, beliefs about consequences, social influences, behavioural regulation. Further analysis at the construct level resulted in selection of seven theoretical approaches relevant to this context: Knowledge-Attitude-Behaviour Model, Theory of Planned Behaviour, Social Cognitive Theory, Operant Learning Theory, Control Theory, Normative Model of Work Team Effectiveness and Action Planning Approaches. This study illustrated, the use of the TDI to identify relevant domains in a complex area of inpatient care. This approach is potentially valuable for selecting theories relevant to predictive studies and resulted in greater breadth of potential explanations than would be achieved if a single theoretical model had been adopted.
Excitation and Ionization Cross Sections for Electron-Beam Energy Deposition in High Temperature Air
1987-07-09
are given and compared to existing experimental results or other theoretical approaches. This information can readily be used as input for a deposition...of the doubly-differential, singly- differential and total ionization cross sections which subsequently served to guide theoretical calculations on...coworkers have been leaders in developing a theoretical base for studying electron production and energy deposition in atmospheric gases such as He, N2
ERIC Educational Resources Information Center
Haj-Yahia, Muhammad M.; Uysal, Aynur
2011-01-01
An integrative theoretical framework was tested as the basis for explaining beliefs about wife beating among Turkish nursing students. Based on a survey design, 406 nursing students (404 females) in all 4 years of undergraduate studies completed a self-administered questionnaire. Questionnaires were distributed and collected from the participants…
A beginner's guide to writing the nursing conceptual model-based theoretical rationale.
Gigliotti, Eileen; Manister, Nancy N
2012-10-01
Writing the theoretical rationale for a study can be a daunting prospect for novice researchers. Nursing's conceptual models provide excellent frameworks for placement of study variables, but moving from the very abstract concepts of the nursing model to the less abstract concepts of the study variables is difficult. Similar to the five-paragraph essay used by writing teachers to assist beginning writers to construct a logical thesis, the authors of this column present guidelines that beginners can follow to construct their theoretical rationale. This guide can be used with any nursing conceptual model but Neuman's model was chosen here as the exemplar.
ERIC Educational Resources Information Center
Benson, Phil, Ed.; Reinders, Hayo, Ed.
2011-01-01
This comprehensive exploration of theoretical and practical aspects of out-of-class teaching and learning, from a variety of perspectives and in various settings around the world, includes a theoretical overview of the field, 11 data-based case studies, and practical advice on materials development for independent learning. Contents of this book…
ERIC Educational Resources Information Center
Smith-Tolken, Antoinette; Bitzer, Eli
2017-01-01
This study addresses underlying principles to interpret scholarly-based service-related teaching and learning. Such principles include addressing specific concerns of communities, transforming theoretical knowledge into lived experiences for students, making the knowledge generated within communities meaningful and forging constant growth and…
An e-Learning Theoretical Framework
ERIC Educational Resources Information Center
Aparicio, Manuela; Bacao, Fernando; Oliveira, Tiago
2016-01-01
E-learning systems have witnessed a usage and research increase in the past decade. This article presents the e-learning concepts ecosystem. It summarizes the various scopes on e-learning studies. Here we propose an e-learning theoretical framework. This theory framework is based upon three principal dimensions: users, technology, and services…
Theoretical framework to study exercise motivation for breast cancer risk reduction.
Wood, Maureen E
2008-01-01
To identify an appropriate theoretical framework to study exercise motivation for breast cancer risk reduction among high-risk women. An extensive review of the literature was conducted to gather relevant information pertaining to the Health Promotion Model, self-determination theory, social cognitive theory, Health Belief Model, Transtheoretical Model, theory of planned behavior, and protection motivation theory. An iterative approach was used to summarize the literature related to exercise motivation within each theoretical framework. Protection motivation theory could be used to examine the effects of perceived risk and self-efficacy in motivating women to exercise to facilitate health-related behavioral change. Evidence-based research within a chosen theoretical model can aid practitioners when making practical recommendations to reduce breast cancer risk.
Guino-o, Marites A.; Alexander, Jacob S.; McKee, Michael L.; Hope, Håkon; Englich, Ulrich B.
2014-01-01
The synthesis, structural, and spectral characterization as well as a theoretical study of a family of alkaline-earth-metal acetylides provides insights into synthetic access and the structural and bonding characteristics of this group of highly reactive compounds. Based on our earlier communication that reported unusual geometry for a family of triphenylsilyl-substituted alkaline-earth-metal acetylides, we herein present our studies on an expanded family of target derivatives, providing experimental and theoretical data to offer new insights into the intensively debated theme of structural chemistry in heavy alkaline-earth-metal chemistry. PMID:19844925
NASA Astrophysics Data System (ADS)
Golbedaghi, Reza; Azimi, Saeid; Molaei, Atefeh; Hatami, Masoud; Notash, Behrouz
2017-10-01
A new Schiff base ligand HL, 1,3-bis(2-((Z)-(2-aminoethylimino)methyl)phenoxy)ethylene di amine, has been synthesized from the reaction of a new aldehyde and ethylenediamine. After preparation the Schiff base, a new dinuclear Cu(II) complex with two different geometry for each metal ion was synthesized. Single crystal X-ray structure analysis of the complex Cu(II) showed that the complex is binuclear and all nitrogen and oxygen atoms of ligand (N4O3) are coordinated to two Cu(II) center ions. The crystal structure studying shows, a perchlorate ion has been coordinated to the two Cu(II) metal centers as bridged and another perchlorate coordinated to the one of Cu(II) ion as terminal. However, two interesting structures square pyramidal and distorted octahedral Cu(II) ions are bridged asymmetrically by a perchlorate ion and oxygen of hydroxyl group of Schiff base ligand. In addition, we had a theoretical study to have a comparison of experimental and theoretical results we determined the HOMO and LUMO orbitals.
ERIC Educational Resources Information Center
Matsumoto, Mitsuko
2015-01-01
Some argue that the field of study of "education and conflict" has yet to be solidified since its emergence in the 1990s, partly due to the weak theory base. This article reviews the literature on the "contribution" of schooling in contemporary violent conflict, via three strands of theoretical ideas, to demonstrate the…
Theoretical study of local structure for Ni2+ ions at tetragonal sites in K2ZnF4:Ni2+ system.
Wang, Su-Juan; Kuang, Xiao-Yu; Lu, Cheng
2008-12-15
A theoretical method for studying the local lattice structure of Ni2+ ions in (NiF6)(4-) coordination complex is presented. Using the ligand-field model, the formulas relating the microscopic spin Hamiltonian parameters with the crystal structure parameters are derived. Based on the theoretical formulas, the 45 x 45 complete energy matrices for d8 (d2) configuration ions in a tetragonal ligand-field are constructed. By diagonalizing the complete energy matrices, the local distortion structure parameters (R perpendicular and R || ) of Ni2+ ions in K2ZnF4:Ni2+ system have been investigated. The theoretical results are accorded well with the experimental values. Moreover, to understand the detailed physical and chemical properties of the fluoroperovskite crystals, the theoretical values of the g factor of K2ZnF4:Ni2+ system at 78 and 290 K are reported first.
Theoretical study of local structure for Ni 2+ ions at tetragonal sites in K 2ZnF 4:Ni 2+ system
NASA Astrophysics Data System (ADS)
Wang, Su-Juan; Kuang, Xiao-Yu; Lu, Cheng
2008-12-01
A theoretical method for studying the local lattice structure of Ni 2+ ions in (NiF 6) 4- coordination complex is presented. Using the ligand-field model, the formulas relating the microscopic spin Hamiltonian parameters with the crystal structure parameters are derived. Based on the theoretical formulas, the 45 × 45 complete energy matrices for d8 ( d2) configuration ions in a tetragonal ligand-field are constructed. By diagonalizing the complete energy matrices, the local distortion structure parameters ( R⊥ and R||) of Ni 2+ ions in K 2ZnF 4:Ni 2+ system have been investigated. The theoretical results are accorded well with the experimental values. Moreover, to understand the detailed physical and chemical properties of the fluoroperovskite crystals, the theoretical values of the g factor of K 2ZnF 4:Ni 2+ system at 78 and 290 K are reported first.
Perceived barriers to completing an e-learning program on evidence-based medicine.
Gagnon, Marie-Pierre; Légaré, France; Labrecque, Michel; Frémont, Pierre; Cauchon, Michel; Desmartis, Marie
2007-01-01
The Continuing Professional Development Center of the Faculty of Medicine at Laval University offers an internet-based program on evidence-based medicine (EBM). After one year, only three physicians out of the 40 who willingly paid to register had completed the entire program. This descriptive study aimed to identify physicians' beliefs regarding their completion of this online program. Using theoretical concepts from the Theory of Planned Behaviour, a semi-structured telephone interview guide was developed to assess respondents' attitudes, perceived subjective norms, perceived obstacles and facilitating conditions with respect to completing this internet-based program. Three independent reviewers performed content analysis of the interview transcripts to obtain an appropriate level of reliability. Findings were shared and organised according to theoretical categories of beliefs. A total of 35 physicians (88% response rate) were interviewed. Despite perceived advantages to completing the internet-based program, barriers remained, especially those related to physicians' perceptions of time constraints. Lack of personal discipline and unfamiliarity with computers were also perceived as important barriers. This study offers a theoretical basis to understand physicians' beliefs towards completing an internet-based continuing medical education (CME) program on EBM. Based upon respondents' insights, several modifications were carried out to enhance the uptake of the program by physicians and, therefore, its implementation.
Witkiewitz, Katie; Bowen, Sarah; Harrop, Erin N; Douglas, Haley; Enkema, Matthew; Sedgwick, Carly
2014-04-01
Mindfulness-based treatments are growing in popularity among addiction treatment providers, and several studies suggest the efficacy of incorporating mindfulness practices into the treatment of addiction, including the treatment of substance use disorders and behavioral addictions (i.e., gambling). The current paper provides a review of theoretical models of mindfulness in the treatment of addiction and several hypothesized mechanisms of change. We provide an overview of mindfulness-based relapse prevention (MBRP), including session content, treatment targets, and client feedback from participants who have received MBRP in the context of empirical studies. Future research directions regarding operationalization and measurement, identifying factors that moderate treatment effects, and protocol adaptations for specific populations are discussed.
Theoretical modeling and experimental analysis of solar still integrated with evacuated tubes
NASA Astrophysics Data System (ADS)
Panchal, Hitesh; Awasthi, Anuradha
2017-06-01
In this present research work, theoretical modeling of single slope, single basin solar still integrated with evacuated tubes has been performed based on energy balance equations. Major variables like water temperature, inner glass cover temperature and distillate output has been computed based on theoretical modeling. The experimental setup has been made from locally available materials and installed at Gujarat Power Engineering and Research Institute, Mehsana, Gujarat, India (23.5880°N, 72.3693°E) with 0.04 m depth during 6 months of time interval. From the series of experiments, it is found considerable increment in average distillate output of a solar still when integrated with evacuated tubes not only during daytime but also from night time. In all experimental cases, the correlation of coefficient (r) and root mean square percentage deviation of theoretical modeling and experimental study found good agreement with 0.97 < r < 0.98 and 10.22 < e < 38.4% respectively.
Integrated Media: Toward a Theoretical Framework for Utilizing Their Potential.
ERIC Educational Resources Information Center
Journal of Special Education Technology, 1993
1993-01-01
This article discusses how current theories of learning and memory can guide the application of integrated media (IM) to embellish a standard curriculum; considers theoretical reasons for "breaking the mold"; and offers examples of IM-based alternatives to curricula in the areas of adult literacy, language arts, social studies, language skills,…
Description and Recognition of the Concept of Social Capital in Higher Education System
ERIC Educational Resources Information Center
Tonkaboni, Forouzan; Yousefy, Alireza; Keshtiaray, Narges
2013-01-01
The current research is intended to describe and recognize the concept of social capital in higher education based on theoretical method in a descriptive-analytical approach. Description and Recognition of the data, gathered from theoretical and experimental studies, indicated that social capital is one of the most important indices for…
ERIC Educational Resources Information Center
Harker, William John
This study was designed: (1) to determine current concepts of reading comprehension deriving from experimental investigations and theoretical statements, and (2) to establish whether these concepts are represented consistently in current secondary professional reading textbooks, instructional materials, and published tests. Current knowledge of…
Testing the Efficacy of Theoretically Derived Improvements in the Treatment of Social Phobia
ERIC Educational Resources Information Center
Rapee, Ronald M.; Gaston, Jonathan E.; Abbott, Maree J.
2009-01-01
Recent theoretical models of social phobia suggest that targeting several specific cognitive factors in treatment should enhance treatment efficacy over that of more traditional skills-based treatment programs. In the current study, 195 people with social phobia were randomly allocated to 1 of 3 treatments: standard cognitive restructuring plus in…
Analysis of rosen piezoelectric transformers with a varying cross-section.
Xue, H; Yang, J; Hu, Y
2008-07-01
We study the effects of a varying cross-section on the performance of Rosen piezoelectric transformers operating with length extensional modes of rods. A theoretical analysis is performed using an extended version of a one-dimensional model developed in a previous paper. Numerical results based on the theoretical analysis are presented.
ERIC Educational Resources Information Center
Ulvund, Stein Erik
1982-01-01
Argues that in analyzing effects of early experience on development of cognitive competence, theoretical analyses as well as empirical investigations should be based on a transactional model of development. Shows optimal stimulation hypothesis, particularly the enhancement prediction, seems to represent a transactional approach to the study of…
ERIC Educational Resources Information Center
Black, David S.; Sussman, Steve; Unger, Jennifer B.
2010-01-01
The intergenerational transmission (IGT) of violence has been a main theoretical consideration to explain the link between interparental aggression in the family of origin and intimate partner violence (IPV) in subsequent intimate relationships. Studies have examined this theoretical link based on self reports of interparental violence witnessed…
Theoretical Beliefs and Instructional Practices Used for Teaching Spelling in Elementary Classrooms
ERIC Educational Resources Information Center
McNeill, Brigid; Kirk, Cecilia
2014-01-01
The current study aimed to examine teachers' reported spelling assessment and instruction practices. Analysis of the match between teachers' theoretical beliefs about spelling and their reported pedagogy was conducted to elucidate factors that may support or impede the use of evidence-based teaching strategies in the classroom. An electronic…
Measuring Experiential Avoidance: A Preliminary Test of a Working Model
ERIC Educational Resources Information Center
Hayes, Steven C.; Strosahl, Kirk; Wilson, Kelly G.; Bissett, Richard T.; Pistorello, Jacqueline; Toarmino, Dosheen; Polusny, Melissa A.; Dykstra, Thane A.; Batten, Sonja V.; Bergan, John; Stewart, Sherry H.; Zvolensky, Michael J.; Eifert, Georg H.; Bond, Frank W.; Forsyth, John P.; Karekla, Maria; Mccurry, Susan M.
2004-01-01
The present study describes the development of a short, general measure of experiential avoidance, based on a specific theoretical approach to this process. A theoretically driven iterative exploratory analysis using structural equation modeling on data from a clinical sample yielded a single factor comprising 9 items. A fully confirmatory factor…
Ab-Initio Calculation of the Magnetic Properties of Metal-Doped Boron-Nitrogen Nanoribbon
NASA Astrophysics Data System (ADS)
Rufinus, J.
2017-10-01
The field of spintronics has been continuously attracting researchers. Tremendous efforts have been made in the quest to find good candidates for future spintronic devices. One particular type of material called graphene is under extensive theoretical study as a feasible component for practical applications. However, pristine graphene is diamagnetic. Thus, a lot of research has been performed to modify the graphene-based structure to achieve meaningful magnetic properties. Recently, a new type of graphene-based one-dimensional material called Boron Nitrogen nanoribbon (BNNR) has been of interest, due to the theoretical predictions that this type of material shows half-metallic property. Here we present the results of the theoretical and computational study of M-doped (M = Cr, Mn) Zigzag BNNR (ZBNNR), the objective of which is to determine whether the presence of these dopants will give rise to ferromagnetism. We have found that the concentration and the atomic distance among the dopants affect the magnetic ordering of this type of material. These results provide a meaningful theoretical prediction of M-doped ZBNNR as a basic candidate of future spintronic devices.
Shentu, Nanying; Zhang, Hongjian; Li, Qing; Zhou, Hongliang; Tong, Renyuan; Li, Xiong
2012-01-01
Deep displacement observation is one basic means of landslide dynamic study and early warning monitoring and a key part of engineering geological investigation. In our previous work, we proposed a novel electromagnetic induction-based deep displacement sensor (I-type) to predict deep horizontal displacement and a theoretical model called equation-based equivalent loop approach (EELA) to describe its sensing characters. However in many landslide and related geological engineering cases, both horizontal displacement and vertical displacement vary apparently and dynamically so both may require monitoring. In this study, a II-type deep displacement sensor is designed by revising our I-type sensor to simultaneously monitor the deep horizontal displacement and vertical displacement variations at different depths within a sliding mass. Meanwhile, a new theoretical modeling called the numerical integration-based equivalent loop approach (NIELA) has been proposed to quantitatively depict II-type sensors’ mutual inductance properties with respect to predicted horizontal displacements and vertical displacements. After detailed examinations and comparative studies between measured mutual inductance voltage, NIELA-based mutual inductance and EELA-based mutual inductance, NIELA has verified to be an effective and quite accurate analytic model for characterization of II-type sensors. The NIELA model is widely applicable for II-type sensors’ monitoring on all kinds of landslides and other related geohazards with satisfactory estimation accuracy and calculation efficiency. PMID:22368467
Shentu, Nanying; Zhang, Hongjian; Li, Qing; Zhou, Hongliang; Tong, Renyuan; Li, Xiong
2012-01-01
Deep displacement observation is one basic means of landslide dynamic study and early warning monitoring and a key part of engineering geological investigation. In our previous work, we proposed a novel electromagnetic induction-based deep displacement sensor (I-type) to predict deep horizontal displacement and a theoretical model called equation-based equivalent loop approach (EELA) to describe its sensing characters. However in many landslide and related geological engineering cases, both horizontal displacement and vertical displacement vary apparently and dynamically so both may require monitoring. In this study, a II-type deep displacement sensor is designed by revising our I-type sensor to simultaneously monitor the deep horizontal displacement and vertical displacement variations at different depths within a sliding mass. Meanwhile, a new theoretical modeling called the numerical integration-based equivalent loop approach (NIELA) has been proposed to quantitatively depict II-type sensors' mutual inductance properties with respect to predicted horizontal displacements and vertical displacements. After detailed examinations and comparative studies between measured mutual inductance voltage, NIELA-based mutual inductance and EELA-based mutual inductance, NIELA has verified to be an effective and quite accurate analytic model for characterization of II-type sensors. The NIELA model is widely applicable for II-type sensors' monitoring on all kinds of landslides and other related geohazards with satisfactory estimation accuracy and calculation efficiency.
1981-08-01
electro - optic effect is investigated both theoretically and experimentally. The theoretical approach is based upon W.A. Harrison’s ’Bond-Orbital Model’. The separate electronic and lattice contributions to the second-order, electro - optic susceptibility are examined within the context of this model and formulae which can accommodate any crystal structure are presented. In addition, a method for estimating the lattice response to a low frequency (dc) electric field is outlined. Finally, experimental measurements of the electro -
Gifford, Wendy; Graham, Ian D; Ehrhart, Mark G; Davies, Barbara L; Aarons, Gregory A
2017-01-01
Leadership in health care is instrumental to creating a supportive organizational environment and positive staff attitudes for implementing evidence-based practices to improve patient care and outcomes. The purpose of this study is to demonstrate the alignment of the Ottawa Model of Implementation Leadership (O-MILe), a theoretical model for developing implementation leadership, with the Implementation Leadership Scale (ILS), an empirically validated tool for measuring implementation leadership. A secondary objective is to describe the methodological process for aligning concepts of a theoretical model with an independently established measurement tool for evaluating theory-based interventions. Modified template analysis was conducted to deductively map items of the ILS onto concepts of the O-MILe. An iterative process was used in which the model and scale developers (n=5) appraised the relevance, conceptual clarity, and fit of each ILS items with the O-MILe concepts through individual feedback and group discussions until consensus was reached. All 12 items of the ILS correspond to at least one O-MILe concept, demonstrating compatibility of the ILS as a measurement tool for the O-MILe theoretical constructs. The O-MILe provides a theoretical basis for developing implementation leadership, and the ILS is a compatible tool for measuring leadership based on the O-MILe. Used together, the O-MILe and ILS provide an evidence- and theory-based approach for developing and measuring leadership for implementing evidence-based practices in health care. Template analysis offers a convenient approach for determining the compatibility of independently developed evaluation tools to test theoretical models.
Gifford, Wendy; Graham, Ian D; Ehrhart, Mark G; Davies, Barbara L; Aarons, Gregory A
2017-01-01
Purpose Leadership in health care is instrumental to creating a supportive organizational environment and positive staff attitudes for implementing evidence-based practices to improve patient care and outcomes. The purpose of this study is to demonstrate the alignment of the Ottawa Model of Implementation Leadership (O-MILe), a theoretical model for developing implementation leadership, with the Implementation Leadership Scale (ILS), an empirically validated tool for measuring implementation leadership. A secondary objective is to describe the methodological process for aligning concepts of a theoretical model with an independently established measurement tool for evaluating theory-based interventions. Methods Modified template analysis was conducted to deductively map items of the ILS onto concepts of the O-MILe. An iterative process was used in which the model and scale developers (n=5) appraised the relevance, conceptual clarity, and fit of each ILS items with the O-MILe concepts through individual feedback and group discussions until consensus was reached. Results All 12 items of the ILS correspond to at least one O-MILe concept, demonstrating compatibility of the ILS as a measurement tool for the O-MILe theoretical constructs. Conclusion The O-MILe provides a theoretical basis for developing implementation leadership, and the ILS is a compatible tool for measuring leadership based on the O-MILe. Used together, the O-MILe and ILS provide an evidence- and theory-based approach for developing and measuring leadership for implementing evidence-based practices in health care. Template analysis offers a convenient approach for determining the compatibility of independently developed evaluation tools to test theoretical models. PMID:29355212
Oussalah, Abderrahim; Fournier, Jean-Paul; Guéant, Jean-Louis; Braun, Marc
2015-02-01
Data regarding knowledge acquisition during residency training are sparse. Predictors of theoretical learning quality, academic career achievements and evidence-based medical practice during residency are unknown. We performed a cross-sectional study on residents and attending physicians across several residency programs in 2 French faculties of medicine. We comprehensively evaluated the information-seeking behavior (I-SB) during residency using a standardized questionnaire and looked for independent predictors of theoretical learning quality, academic career achievements, and evidence-based medical practice among I-SB components using multivariate logistic regression analysis. Between February 2013 and May 2013, 338 fellows and attending physicians were included in the study. Textbooks and international medical journals were reported to be used on a regular basis by 24% and 57% of the respondents, respectively. Among the respondents, 47% refer systematically (4.4%) or frequently (42.6%) to published guidelines from scientific societies upon their publication. The median self-reported theoretical learning quality score was 5/10 (interquartile range, 3-6; range, 1-10). A high theoretical learning quality score (upper quartile) was independently and strongly associated with the following I-SB components: systematic reading of clinical guidelines upon their publication (odds ratio [OR], 5.55; 95% confidence interval [CI], 1.77-17.44); having access to a library that offers the leading textbooks of the specialty in the medical department (OR, 2.45, 95% CI, 1.33-4.52); knowledge of the specialty leading textbooks (OR, 2.12; 95% CI, 1.09-4.10); and PubMed search skill score ≥5/10 (OR, 1.94; 95% CI, 1.01-3.73). Research Master (M2) and/or PhD thesis enrolment were independently and strongly associated with the following predictors: PubMed search skill score ≥5/10 (OR, 4.10; 95% CI, 1.46-11.53); knowledge of the leading medical journals of the specialty (OR, 3.33; 95% CI, 1.32-8.38); attending national and international academic conferences and meetings (OR, 2.43; 95% CI, 1.09-5.43); and using academic theoretical learning supports several times a week (OR, 2.23; 95% CI, 1.11- 4.49). This study showed weaknesses in the theoretical learning framework during residency. I-SB was independently associated with quality of academic theoretical learning, academic career achievements, and the use of evidence-based medicine in everyday clinical practice. CNIL No.1797639.
Measuring metacognitive ability based on science literacy in dynamic electricity topic
NASA Astrophysics Data System (ADS)
Warni; Sunyono; Rosidin
2018-01-01
This study aims to produce an instrument of metacognition ability assessment based on science literacy on theoretically and empirically feasible dynamic electrical material. The feasibility of the assessment instrument includes theoretical validity on material, construction, and language aspects, as well as empirical validity, reliability, difficulty, distinguishing, and distractor indices. The development of assessment instruments refers to the Dick and Carey development model which includes the preliminary study stage, initial product development, validation and revision, and piloting. The instrument was tested to 32 students of class IX in SMP Negeri 20 Bandar Lampung, using the design of One Group Pretest-Postest Design. The result shows that the metacognition ability assessment instrument based on science literacy is feasible theoretically with theoretical validity percentage of 95.44% and empirical validity of 43.75% for the high category, 43.75% for the medium category, and 12.50 % for low category questions; Reliability of assessment instruments of 0.83 high categories; Difficulty level of difficult item is about 31.25% and medium category is equal to 68.75%. Item that has very good distinguishing power is 12.50%, 62.50% for good stage, and medium category is 25.00%; As well as the duplexing function on a matter of multiple choice is 80.00% including good category and 20.00% for medium category.
Theoretical investigation of gas-surface interactions
NASA Technical Reports Server (NTRS)
Lee, Timothy J.
1989-01-01
Four reprints are presented from four projects which are to be published in a refereed journal. Two are of interest to us and are presented herein. One is a description of a very detailed theoretical study of four anionic hydrogen bonded complexes. The other is a detailed study of the first generally reliable diagnostic for determining the quality of results that may be expected from single reference based electron correlation methods.
A new theoretical approach to adsorption desorption behavior of Ga on GaAs surfaces
NASA Astrophysics Data System (ADS)
Kangawa, Y.; Ito, T.; Taguchi, A.; Shiraishi, K.; Ohachi, T.
2001-11-01
We propose a new theoretical approach for studying adsorption-desorption behavior of atoms on semiconductor surfaces. The new theoretical approach based on the ab initio calculations incorporates the free energy of gas phase; therefore we can calculate how adsorption and desorption depends on growth temperature and beam equivalent pressure (BEP). The versatility of the new theoretical approach was confirmed by the calculation of Ga adsorption-desorption transition temperatures and transition BEPs on the GaAs(0 0 1)-(4×2)β2 Ga-rich surface. This new approach is feasible to predict how adsorption and desorption depend on the growth conditions.
2010-12-20
Optical chromatography Size determination by eluting particles ,” Talanta 48(3), 551–557 (1999). 15. A. Ashkin, and J. M. Dziedzic, “Optical levitation ...the use of optical force in the gas phase, for example, levitation of airborne particles [15,16], and more recent studies on aerosol optical guiding...On-the-fly cross flow laser guided separation of aerosol particles based on size, refractive index and density–theoretical analysis A. A. Lall
Origin of traps and charge transport mechanism in hafnia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Islamov, D. R., E-mail: damir@isp.nsc.ru; Gritsenko, V. A., E-mail: grits@isp.nsc.ru; Novosibirsk State University, Novosibirsk 630090
2014-12-01
In this study, we demonstrated experimentally and theoretically that oxygen vacancies are responsible for the charge transport in HfO{sub 2}. Basing on the model of phonon-assisted tunneling between traps, and assuming that the electron traps are oxygen vacancies, good quantitative agreement between the experimental and theoretical data of current-voltage characteristics was achieved. The thermal trap energy of 1.25 eV in HfO{sub 2} was determined based on the charge transport experiments.
Keil, D; Holmes, P; Bennett, S; Davids, K; Smith, N
2000-06-01
Because of advances in technology, the non-invasive study of the human brain has enhanced the knowledge base within the neurosciences, resulting in an increased impact on the psychological study of human behaviour. We argue that application of this knowledge base should be considered in theoretical modelling within sport psychology and motor behaviour alongside existing ideas. We propose that interventions founded on current theoretical and empirical understanding in both psychology and the neurosciences may ultimately lead to greater benefits for athletes during practice and performance. As vehicles for exploring the arguments of a greater integration of psychology and neurosciences research, imagery and perception-action within the sport psychology and motor behaviour domains will serve as exemplars. Current neuroscience evidence will be discussed in relation to theoretical developments; the implications for sport scientists will be considered.
Seror, Valerie
2008-05-01
Choices regarding prenatal diagnosis of Down syndrome - the most frequent chromosomal defect - are particularly relevant to decision analysis, since women's decisions are based on the assessment of their risk of carrying a child with Down syndrome, and involve tradeoffs (giving birth to an affected child vs procedure-related miscarriage). The aim of this study, based on face-to-face interviews with 78 women aged 25-35 with prior experience of pregnancy, was to compare the women' expressed choices towards prenatal diagnosis with those derived from theoretical models of choice (expected utility theory, rank-dependent theory, and cumulative prospect theory). The main finding obtained in this study was that the cumulative prospect model fitted the observed choices best: both subjective transformation of probabilities and loss aversion, which are basic features of the cumulative prospect model, have to be taken into account to make the observed choices consistent with the theoretical ones.
Numerical computation of hurricane effects on historic coastal hydrology in Southern Florida
Swain, Eric D.; Krohn, M. Dennis; Langtimm, Catherine A.
2015-01-01
The hindcast simulation estimated hydrologic processes for the 1926 to 1932 period. It shows promise as a simulator in long-term ecological studies to test hypotheses based on theoretical or empirical-based studies at larger landscape scales.
Input-Based Approaches to Teaching Grammar: A Review of Classroom-Oriented Research.
ERIC Educational Resources Information Center
Ellis, Rod
1999-01-01
Examines the theoretical rationales (universal grammar, information-processing theories, skill-learning theories) for input-based grammar teaching and reviews classroom-oriented research (i.e., enriched-input studies, input-processing studies) that has integrated this option. (Author/VWL)
NASA Astrophysics Data System (ADS)
Chen, Ying; Yuan, Jianghong; Zhang, Yingchao; Huang, Yonggang; Feng, Xue
2017-10-01
The interfacial failure of integrated circuit (IC) chips integrated on flexible substrates under bending deformation has been studied theoretically and experimentally. A compressive buckling test is used to impose the bending deformation onto the interface between the IC chip and the flexible substrate quantitatively, after which the failed interface is investigated using scanning electron microscopy. A theoretical model is established based on the beam theory and a bi-layer interface model, from which an analytical expression of the critical curvature in relation to the interfacial failure is obtained. The relationships between the critical curvature, the material, and the geometric parameters of the device are discussed in detail, providing guidance for future optimization flexible circuits based on IC chips.
Principles and performance of tapered fiber lasers: from uniform to flared geometry.
Kerttula, Juho; Filippov, Valery; Chamorovskii, Yuri; Ustimchik, Vasily; Golant, Konstantin; Okhotnikov, Oleg G
2012-10-10
We have studied the recently demonstrated concept of fiber lasers based on active tapered double-clad fiber (T-DCF) in copropagating and counterpropagating configurations, both theoretically and experimentally, and compared the performance to fiber lasers based on conventional cylindrical fibers in end-pumped configurations. Specific properties of T-DCFs were considered theoretically using a rate-equation model developed for tapered fibers, and a detailed comparative study was carried out experimentally. Furthermore, we have studied mode coupling effects in long adiabatic tapers due to coiling and local bending. The results allow us to conclude that, with proper fiber design, the T-DCF technology offers a high-potential alternative for bright, cost-effective fiber devices.
Beyond the Four Ps: A Theoretical Explication and Research Agenda for Social Marketing.
ERIC Educational Resources Information Center
Sego, Trina
Advocates of social marketing in the 1970s rarely went beyond discussion of the marketing 4Ps (product, place, promotion, and price) and their application to case studies. After two decades of research on social marketing, some misunderstanding of the approach persists, and a substantial theoretical base for social marketing has not been…
ERIC Educational Resources Information Center
Pearce, Craig L.; Sims, Henry P., Jr.; Cox, Jonathan F.; Ball, Gail; Schnell, Eugene; Smith, Ken A.; Trevino, Linda
2003-01-01
To extend the transactional-transformational model of leadership, four theoretical behavioral types of leadership were developed based on literature review and data from studies of executive behavior (n=253) and subordinate attitudes (n=208). Confirmatory factor analysis of a third data set (n=702) support the existence of four leadership types:…
A Theoretical Foundation for the Study of Inferential Error in Decision-Making Groups.
ERIC Educational Resources Information Center
Gouran, Dennis S.
To provide a theoretical base for investigating the influence of inferential error on group decision making, current literature on both inferential error and decision making is reviewed and applied to the Watergate incident. Although groups tend to make fewer inferential errors because members' inferences are generally not biased in the same…
ERIC Educational Resources Information Center
Newman, Tim A.
2012-01-01
This study described the current state of principal salaries in South Carolina and compared the salaries of similar size schools by specific report card performance and demographic variables. Based on the findings, theoretical models were proposed, and comparisons were made with current salary data. School boards, human resource personnel and…
Witkiewitz, Katie; Bowen, Sarah; Harrop, Erin N.; Douglas, Haley; Enkema, Matthew; Sedgwick, Carly
2017-01-01
Mindfulness-based treatments are growing in popularity among addiction treatment providers, and several studies suggest the efficacy of incorporating mindfulness practices into the treatment of addiction, including the treatment of substance use disorders and behavioral addictions (i.e., gambling). The current paper provides a review of theoretical models of mindfulness in the treatment of addiction and several hypothesized mechanisms of change. We provide an overview of mindfulness-based relapse prevention (MBRP), including session content, treatment targets, and client feedback from participants who have received MBRP in the context of empirical studies. Future research directions regarding operationalization and measurement, identifying factors that moderate treatment effects, and protocol adaptations for specific populations are discussed. PMID:24611847
NASA Astrophysics Data System (ADS)
Tsaturyan, Arshak; Machida, Yosuke; Akitsu, Takashiro; Gozhikova, Inna; Shcherbakov, Igor
2018-06-01
We report on synthesis and characterization of binaphthyl containing Schiff base Ni(II), Cu(II), and Zn(II) complexes as promising photosensitizers for dye-sensitized solar cells (DSSC). Based on theoretical and experimental data, the possibility of their application in DSSC was confirmed. To our knowledge, we find dye performance of complex is steric and rigid structure widely spread to efficiency. The spatial and electronic structures of the complexes were studied by means of the quantum chemical modeling using DFT and TD-DFT approaches. The adsorption energies of the complexes on TiO2 cluster were calculated and appeared to be very close in value. The Zn(II) complex has the biggest value of molar extinction.
Evaluation of the Professional Development Program on Web Based Content Development
ERIC Educational Resources Information Center
Yurdakul, Bünyamin; Uslu, Öner; Çakar, Esra; Yildiz, Derya G.
2014-01-01
The aim of this study is to evaluate the professional development program on web based content development (WBCD) designed by the Ministry of National Education (MoNE). Based on the theoretical CIPP model by Stufflebeam and Guskey's levels of evaluation, the study was carried out as a case study. The study group consisted of the courses that…
Gould, Natalie J; Lorencatto, Fabiana; Stanworth, Simon J; Michie, Susan; Prior, Maria E; Glidewell, Liz; Grimshaw, Jeremy M; Francis, Jill J
2014-07-29
Audits of blood transfusion demonstrate around 20% transfusions are outside national recommendations and guidelines. Audit and feedback is a widely used quality improvement intervention but effects on clinical practice are variable, suggesting potential for enhancement. Behavioural theory, theoretical frameworks of behaviour change and behaviour change techniques provide systematic processes to enhance intervention. This study is part of a larger programme of work to promote the uptake of evidence-based transfusion practice. The objectives of this study are to design two theoretically enhanced audit and feedback interventions; one focused on content and one on delivery, and investigate the feasibility and acceptability. Study A (Content): A coding framework based on current evidence regarding audit and feedback, and behaviour change theory and frameworks will be developed and applied as part of a structured content analysis to specify the key components of existing feedback documents. Prototype feedback documents with enhanced content and also a protocol, describing principles for enhancing feedback content, will be developed. Study B (Delivery): Individual semi-structured interviews with healthcare professionals and observations of team meetings in four hospitals will be used to specify, and identify views about, current audit and feedback practice. Interviews will be based on a topic guide developed using the Theoretical Domains Framework and the Consolidated Framework for Implementation Research. Analysis of transcripts based on these frameworks will form the evidence base for developing a protocol describing an enhanced intervention that focuses on feedback delivery. Study C (Feasibility and Acceptability): Enhanced interventions will be piloted in four hospitals. Semi-structured interviews, questionnaires and observations will be used to assess feasibility and acceptability. This intervention development work reflects the UK Medical Research Council's guidance on development of complex interventions, which emphasises the importance of a robust theoretical basis for intervention design and recommends systematic assessment of feasibility and acceptability prior to taking interventions to evaluation in a full-scale randomised study. The work-up includes specification of current practice so that, in the trials to be conducted later in this programme, there will be a clear distinction between the control (usual practice) conditions and the interventions to be evaluated.
Theoretical Design Study of a 2-18 GHz Bandwidth Helix TWT (Traveling Wave Tube) Amplifier
1987-02-01
Inckode Security Clanification) THEORETICAL DESIGN STUDY OF A 2-18 GHz BANDWIDTH HELIX TWT AMPLIFIER 12. PERSONAL AUTNOR(S) Michael A. Frisoni 13a. TYPE...in a traveling-wave tube ( TWT ) output circuit in A’ order to realize a 2-18 GHz frequency bandwidth. The nondispersive helix circuit provides the...Input Parameters . . . . . . . . . . . 30 V. ULTRA- BROADBAND THEORY BASED ON TWT COMPUTER SIMULATION • . 33 A. Definitions
NASA Technical Reports Server (NTRS)
Neudeck, Philip G.; Spry, David J.; Chen, Liangyu
2015-01-01
This work reports a theoretical and experimental study of 4H-SiC JFET threshold voltage as a function of substrate body bias, device position on the wafer, and temperature from 25 C (298K) to 500 C (773K). Based on these results, an alternative approach to SPICE circuit simulation of body effect for SiC JFETs is proposed.
Cane, James; O'Connor, Denise; Michie, Susan
2012-04-24
An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework. Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis. There was good support for a refinement of the framework comprising 14 domains of theoretical constructs (average silhouette value 0.29): 'Knowledge', 'Skills', 'Social/Professional Role and Identity', 'Beliefs about Capabilities', 'Optimism', 'Beliefs about Consequences', 'Reinforcement', 'Intentions', 'Goals', 'Memory, Attention and Decision Processes', 'Environmental Context and Resources', 'Social Influences', 'Emotions', and 'Behavioural Regulation'. The refined Theoretical Domains Framework has a strengthened empirical base and provides a method for theoretically assessing implementation problems, as well as professional and other health-related behaviours as a basis for intervention development.
Theoretical and Experimental Estimations of Volumetric Inductive Phase Shift in Breast Cancer Tissue
NASA Astrophysics Data System (ADS)
González, C. A.; Lozano, L. M.; Uscanga, M. C.; Silva, J. G.; Polo, S. M.
2013-04-01
Impedance measurements based on magnetic induction for breast cancer detection has been proposed in some studies. This study evaluates theoretical and experimentally the use of a non-invasive technique based on magnetic induction for detection of patho-physiological conditions in breast cancer tissue associated to its volumetric electrical conductivity changes through inductive phase shift measurements. An induction coils-breast 3D pixel model was designed and tested. The model involves two circular coils coaxially centered and a human breast volume centrally placed with respect to the coils. A time-harmonic numerical simulation study addressed the effects of frequency-dependent electrical properties of tumoral tissue on the volumetric inductive phase shift of the breast model measured with the circular coils as inductor and sensor elements. Experimentally; five female volunteer patients with infiltrating ductal carcinoma previously diagnosed by the radiology and oncology departments of the Specialty Clinic for Women of the Mexican Army were measured by an experimental inductive spectrometer and the use of an ergonomic inductor-sensor coil designed to estimate the volumetric inductive phase shift in human breast tissue. Theoretical and experimental inductive phase shift estimations were developed at four frequencies: 0.01, 0.1, 1 and 10 MHz. The theoretical estimations were qualitatively in agreement with the experimental findings. Important increments in volumetric inductive phase shift measurements were evident at 0.01MHz in theoretical and experimental observations. The results suggest that the tested technique has the potential to detect pathological conditions in breast tissue associated to cancer by non-invasive monitoring. Further complementary studies are warranted to confirm the observations.
Joint research effort on vibrations of twisted plates, phase 1: Final results
NASA Technical Reports Server (NTRS)
Kielb, R. E.; Leissa, A. W.; Macbain, J. C.; Carney, K. S.
1985-01-01
The complete theoretical and experimental results of the first phase of a joint government/industry/university research study on the vibration characteristics of twisted cantilever plates are given. The study is conducted to generate an experimental data base and to compare many different theoretical methods with each other and with the experimental results. Plates with aspect ratios, thickness ratios, and twist angles representative of current gas turbine engine blading are investigated. The theoretical results are generated by numerous finite element, shell, and beam analysis methods. The experimental results are obtained by precision matching a set of twisted plates and testing them at two laboratories. The second and final phase of the study will concern the effects of rotation.
Schumann, Anja; John, Ulrich; Ulbricht, Sabina; Rüge, Jeannette; Bischof, Gallus; Meyer, Christian
2008-11-01
This study examines tailored feedback letters of a smoking cessation intervention that is conceptually based on the transtheoretical model, from a content-based perspective. Data of 2 population-based intervention studies, both randomized controlled trials, with total N=1044 were used. The procedure of the intervention, the tailoring principle for the feedback letters, and the content of the intervention materials are described in detail. Theoretical and empirical frequencies of unique feedback letters are presented. The intervention system was able to generate a total of 1040 unique letters with normative feedback only, and almost half a million unique letters with normative and ipsative feedback. Almost every single smoker in contemplation, preparation, action, and maintenance had an empirically unique combination of tailoring variables and received a unique letter. In contrast, many smokers in precontemplation shared a combination of tailoring variables and received identical letters. The transtheoretical model provides an enormous theoretical and empirical variability of tailoring. However, tailoring for a major subgroup of smokers, i.e. those who do not intend to quit, needs improvement. Conceptual ideas for additional tailoring variables are discussed.
Schnall, Peter; Dobson, Marnie; Israel, Leslie; Landsbergis, Paul; Galassetti, Pietro; Pontello, Andria; Kojaku, Stacey; Baker, Dean
2011-01-01
Firefighters and police officers have the third highest prevalence of obesity among 41 male occupational groups in the United States (US). However, few studies have examined the relationship of firefighter working conditions and health behaviors with obesity. This paper presents a theoretical framework describing the relationship between working conditions, health behaviors, and obesity in firefighters. In addition, the paper describes a detailed study plan for exploring the role of occupational and behavioral risk factors in the development of obesity in firefighters enrolled in the Orange County Fire Authority Wellness Fitness Program. The study plan will be described with emphasis on its methodological merits: adopting a participatory action research approach, developing a firefighter-specific work and health questionnaire, conducting both a cross-sectional epidemiological study using the questionnaire and a sub-study to assess the validity of the questionnaire with dietary intake and physical activity measures, and evaluating the strengths and weaknesses of the body mass index as an obesity measure in comparison to skinfold-based percent body fat. The study plan based on a theoretical framework can be an essential first step for establishing effective intervention programs for obesity among professional and voluntary firefighters. PMID:22953214
Choi, Bongkyoo; Schnall, Peter; Dobson, Marnie; Israel, Leslie; Landsbergis, Paul; Galassetti, Pietro; Pontello, Andria; Kojaku, Stacey; Baker, Dean
2011-12-01
Firefighters and police officers have the third highest prevalence of obesity among 41 male occupational groups in the United States (US). However, few studies have examined the relationship of firefighter working conditions and health behaviors with obesity. This paper presents a theoretical framework describing the relationship between working conditions, health behaviors, and obesity in firefighters. In addition, the paper describes a detailed study plan for exploring the role of occupational and behavioral risk factors in the development of obesity in firefighters enrolled in the Orange County Fire Authority Wellness Fitness Program. The study plan will be described with emphasis on its methodological merits: adopting a participatory action research approach, developing a firefighter-specific work and health questionnaire, conducting both a cross-sectional epidemiological study using the questionnaire and a sub-study to assess the validity of the questionnaire with dietary intake and physical activity measures, and evaluating the strengths and weaknesses of the body mass index as an obesity measure in comparison to skinfold-based percent body fat. The study plan based on a theoretical framework can be an essential first step for establishing effective intervention programs for obesity among professional and voluntary firefighters.
Valente, Marco A G; Teixeira, Deiver A; Azevedo, David L; Feliciano, Gustavo T; Benedetti, Assis V; Fugivara, Cecílio S
2017-01-01
The interaction of volatile corrosion inhibitors (VCI), caprylate salt derivatives from amines, with zinc metallic surfaces is assessed by density functional theory (DFT) computer simulations, electrochemical impedance (EIS) measurements and humid chamber tests. The results obtained by the different methods were compared, and linear correlations were obtained between theoretical and experimental data. The correlations between experimental and theoretical results showed that the molecular size is the determining factor in the inhibition efficiency. The models used and experimental results indicated that dicyclohexylamine caprylate is the most efficient inhibitor.
Impact of implant support on mandibular free-end base removable partial denture: theoretical study.
Oh, Won-suk; Oh, Tae-Ju; Park, Ju-mi
2016-02-01
This study investigated the impact of implant support on the development of shear force and bending moment in mandibular free-end base removable partial dentures (RPDs). Three theoretical test models of unilateral mandibular free-end base RPDs were constructed to represent the base of tooth replacement, as follows: Model 1: first and second molars (M1 and M2); Model 2: second premolar (P2), M1, and M2; and Model 3: first premolar (P1), P2, M1, and M2. The implant support located either at M1 or M2 sites. The occlusal loading was concentrated at each replacement tooth to calculate the stress resultants developed in the RPD models using the free-body diagrams of shear force and bending moment. There was a trend of reduction in the peak shear force and bending moment when the base was supported by implant. However, the degree of reduction varied with the location of implant support. The moment reduced by 76% in Model 1, 58% in Model 2, and 42% in Model 3, when the implant location shifted from M1 to M2 sites. The shear forces and bending moments subjected to mandibular free-end base RPDs were found to decrease with the addition of implant support. However, the impact of implant support varied with the location of implant in this theoretical study. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Superconductivity in layered BiS 2-based compounds
Yazici, D.; Jeon, I.; White, B. D.; ...
2015-02-25
Here, a novel family of superconductors based on BiS 2-based superconducting layers were discovered in 2012. In short order, other BiS 2-based superconductors with the same or related crystal structures were discovered with superconducting critical temperatures T c of up to 10 K. Many experimental and theoretical studies have been carried out with the goal of establishing the basic properties of these new materials and understanding the underlying mechanism for superconductivity. In this selective review of the literature, we distill the central discoveries from this extensive body of work, and discuss the results from different types of experiments on thesemore » materials within the context of theoretical concepts and models.« less
Structural properties of lead-lithium alloys
NASA Astrophysics Data System (ADS)
Khambholja, S. G.; Satikunvar, D. D.; Abhishek, Agraj; Thakore, B. Y.
2018-05-01
Lead-Lihtium alloys have found large number of applications as liquid metal coolants in nuclear reactors. Large number of experimental work is reported for this system. However, complete theoretical description is still rare. In this scenario, we in the present work report the study of ground state properties of Lead-Lithium system. The present study is performed using plane wave pseudopotential density functional theory as implemented in Quantum ESPRESSO package. The theoretical findings are in agreement with previously reported experimental data. Some conclusions are drawn based on present study, which will be helpful for a comprehensive study.
ERIC Educational Resources Information Center
Johnson, Bruce; Manoli, Constantinos C.
2008-01-01
Investigating the effects of educational programmes on children's environmental perceptions has been hampered by the lack of good theoretical models and valid instruments. In the present study, Bogner and Wiseman's Model of Ecological Values provided a well-developed theoretical model. A validated instrument based on Bogner's Environmental…
Support Net for Frontline Providers
2016-03-01
influencing members’ continuance intentions in professional virtual communities - a longitudinal study. Journal of Information Science, 33(4), 451-467...of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB...from a scientific and theoretically based manner. Results from this project provide critical prevalence information , theoretical development, and
ERIC Educational Resources Information Center
Quinn, Frances; Pegg, John; Panizzon, Debra
2009-01-01
Meiosis is a biological concept that is both complex and important for students to learn. This study aims to explore first-year biology students' explanations of the process of meiosis, using an explicit theoretical framework provided by the Structure of the Observed Learning Outcome (SOLO) model. The research was based on responses of 334…
Joint Services Electronics Program.
1985-12-31
year a comprehensive experimental study of the collision- enhanced Hanle-type resonances in Na vapor with various buffer gases has been completed...demonstrated theoretically that the collision-enhanced Hanle resonances are equivalent to the phenomenon of collision-induced transverse optical pumping. The...for the sensitivity of the mean sojourn times. We also developed a set of new equations based on perturbation analysis which calculates theoretically
ERIC Educational Resources Information Center
Tobia, Valentina; Ciancaleoni, Matteo; Bonifacci, Paola
2017-01-01
In this study, two alternative theoretical models were compared, in order to analyze which of them best explains primary school children's text comprehension skills. The first one was based on the distinction between two types of answers requested by the comprehension test: local or global. The second model involved texts' input modality: written…
ERIC Educational Resources Information Center
Ebadi, Saman; Asakereh, Ahmad
2017-01-01
Dynamic assessment (DA), having its theoretical base in Vygotskyan Sociocultural theory of mind, is a newly developed classroom assessment through which learners are helped to perform beyond their current ability. Drawing upon the theoretical aspect of DA, the present study explored the impact of DA on the development of speaking skills. To this…
The Safety Culture Enactment Questionnaire (SCEQ): Theoretical model and empirical validation.
de Castro, Borja López; Gracia, Francisco J; Tomás, Inés; Peiró, José M
2017-06-01
This paper presents the Safety Culture Enactment Questionnaire (SCEQ), designed to assess the degree to which safety is an enacted value in the day-to-day running of nuclear power plants (NPPs). The SCEQ is based on a theoretical safety culture model that is manifested in three fundamental components of the functioning and operation of any organization: strategic decisions, human resources practices, and daily activities and behaviors. The extent to which the importance of safety is enacted in each of these three components provides information about the pervasiveness of the safety culture in the NPP. To validate the SCEQ and the model on which it is based, two separate studies were carried out with data collection in 2008 and 2014, respectively. In Study 1, the SCEQ was administered to the employees of two Spanish NPPs (N=533) belonging to the same company. Participants in Study 2 included 598 employees from the same NPPs, who completed the SCEQ and other questionnaires measuring different safety outcomes (safety climate, safety satisfaction, job satisfaction and risky behaviors). Study 1 comprised item formulation and examination of the factorial structure and reliability of the SCEQ. Study 2 tested internal consistency and provided evidence of factorial validity, validity based on relationships with other variables, and discriminant validity between the SCEQ and safety climate. Exploratory Factor Analysis (EFA) carried out in Study 1 revealed a three-factor solution corresponding to the three components of the theoretical model. Reliability analyses showed strong internal consistency for the three scales of the SCEQ, and each of the 21 items on the questionnaire contributed to the homogeneity of its theoretically developed scale. Confirmatory Factor Analysis (CFA) carried out in Study 2 supported the internal structure of the SCEQ; internal consistency of the scales was also supported. Furthermore, the three scales of the SCEQ showed the expected correlation patterns with the measured safety outcomes. Finally, results provided evidence of discriminant validity between the SCEQ and safety climate. We conclude that the SCEQ is a valid, reliable instrument supported by a theoretical framework, and it is useful to measure the enactment of safety culture in NPPs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Study on the millimeter-wave scale absorber based on the Salisbury screen
NASA Astrophysics Data System (ADS)
Yuan, Liming; Dai, Fei; Xu, Yonggang; Zhang, Yuan
2018-03-01
In order to solve the problem on the millimeter-wave scale absorber, the Salisbury screen absorber is employed and designed based on the RL. By optimizing parameters including the sheet resistance of the surface resistive layer, the permittivity and the thickness of the grounded dielectric layer, the RL of the Salisbury screen absorber could be identical with that of the theoretical scale absorber. An example is given to verify the effectiveness of the method, where the Salisbury screen absorber is designed by the proposed method and compared with the theoretical scale absorber. Meanwhile, plate models and tri-corner reflector (TCR) models are constructed according to the designed result and their scattering properties are simulated by FEKO. Results reveal that the deviation between the designed Salisbury screen absorber and the theoretical scale absorber falls within the tolerance of radar Cross section (RCS) measurement. The work in this paper has important theoretical and practical significance in electromagnetic measurement of large scale ratio.
[Efficacy analysis and theoretical study on Chinese herbal properties of Açaí (Euterpe oleracea)].
Zhang, Jian-jun; Chen, Shao-hong; Zhu, Ying-li; Wang, Chun; Wang, Jing-xia; Wang, Lin-yuan; Gao, Xue-min
2015-06-01
Açaí (Euterpe oleracea) emerged as a source of herb has a long history in South America, which was approved by the Ministry of Health used in China and it has been introduced planting in Guangdong and Taiwan. This article summarized applied history of Açaí and its present status in China. Did theoretical study on the Chinese herbal properties of Açaí based on the Chinese traditional philosophical culture to analysis the function and symptom preliminary, combining with used for medical recordation, chemical component, biological activity. It is aiming at establishing the theoretical foundation for the application under the guidance of TCM theory.
Low Temperature Kinetics of the First Steps of Water Cluster Formation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bourgalais, J.; Roussel, V.; Capron, M.
2016-03-01
We present a combined experimental and theoretical low temperature kinetic study of water cluster formation. Water cluster growth takes place in low temperature (23-69 K) supersonic flows. The observed kinetics of formation of water clusters are reproduced with a kinetic model based on theoretical predictions for the first steps of clusterization. The temperature-and pressure-dependent association and dissociation rate coefficients are predicted with an ab initio transition state theory based master equation approach over a wide range of temperatures (20-100 K) and pressures (10(-6) - 10 bar).
Sneck, Sami; Saarnio, Reetta; Isola, Arja; Boigu, Risto
2016-01-01
Medication administration is an important task of registered nurses. According to previous studies, nurses lack theoretical knowledge and drug calculation skills and knowledge-based mistakes do occur in clinical practice. Finnish health care organizations started to develop a systematic verification processes for medication competence at the end of the last decade. No studies have yet been made of nurses' theoretical knowledge and drug calculation skills according to these online exams. The aim of this study was to describe the medication competence of Finnish nurses according to theoretical and drug calculation exams. A descriptive correlation design was adopted. Participants and settings All nurses who participated in the online exam in three Finnish hospitals between 1.1.2009 and 31.05.2014 were selected to the study (n=2479). Quantitative methods like Pearson's chi-squared tests, analysis of variance (ANOVA) with post hoc Tukey tests and Pearson's correlation coefficient were used to test the existence of relationships between dependent and independent variables. The majority of nurses mastered the theoretical knowledge needed in medication administration, but 5% of the nurses struggled with passing the drug calculation exam. Theoretical knowledge and drug calculation skills were better in acute care units than in the other units and younger nurses achieved better results in both exams than their older colleagues. The differences found in this study were statistically significant, but not high. Nevertheless, even the tiniest deficiency in theoretical knowledge and drug calculation skills should be focused on. It is important to identify the nurses who struggle in the exams and to plan targeted educational interventions for supporting them. The next step is to study if verification of medication competence has an effect on patient safety. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sancho, Leyla Gomes; Dain, Sulamis
2012-03-01
The study aims to infer the existence of a continuum between Health Assessment and Economic Assessment in Health, by highlighting points of intersection of these forms of appraisal. To achieve this, a review of the theoretical foundations, methods and approaches of both forms of assessment was conducted. It was based on the theoretical model of health evaluation as reported by Hartz et al and economic assessment in health approaches reported by Brouwer et al. It was seen that there is a continuum between the theoretical model of evaluative research and the extrawelfarist approach for economic assessment in health, and between the normative theoretical model for health assessment and the welfarist approaches for economic assessment in health. However, in practice the assessment is still conducted using the normative theoretical model and with a welfarist approach.
Theory and interpretation in qualitative studies from general practice: Why and how?
Malterud, Kirsti
2016-03-01
In this article, I want to promote theoretical awareness and commitment among qualitative researchers in general practice and suggest adequate and feasible theoretical approaches. I discuss different theoretical aspects of qualitative research and present the basic foundations of the interpretative paradigm. Associations between paradigms, philosophies, methodologies and methods are examined and different strategies for theoretical commitment presented. Finally, I discuss the impact of theory for interpretation and the development of general practice knowledge. A scientific theory is a consistent and soundly based set of assumptions about a specific aspect of the world, predicting or explaining a phenomenon. Qualitative research is situated in an interpretative paradigm where notions about particular human experiences in context are recognized from different subject positions. Basic theoretical features from the philosophy of science explain why and how this is different from positivism. Reflexivity, including theoretical awareness and consistency, demonstrates interpretative assumptions, accounting for situated knowledge. Different types of theoretical commitment in qualitative analysis are presented, emphasizing substantive theories to sharpen the interpretative focus. Such approaches are clearly within reach for a general practice researcher contributing to clinical practice by doing more than summarizing what the participants talked about, without trying to become a philosopher. Qualitative studies from general practice deserve stronger theoretical awareness and commitment than what is currently established. Persistent attention to and respect for the distinctive domain of knowledge and practice where the research deliveries are targeted is necessary to choose adequate theoretical endeavours. © 2015 the Nordic Societies of Public Health.
Pearson, Barbara Zurer
2004-02-01
Three avenues of theoretical research provide insights for discovering abstract properties of language that are subject to disorder and amenable to assessment: (1) the study of universal grammar and its acquisition; (2) descriptions of African American English (AAE) Syntax, Semantics, and Phonology within theoretical linguistics; and (3) the study of specific language impairment (SLI) cross-linguistically. Abstract linguistic concepts were translated into a set of assessment protocols that were used to establish normative data on language acquisition (developmental milestones) in typically developing AAE children ages 4 to 9 years. Testing AAE-speaking language impaired (LI) children and both typically developing (TD) and LI Mainstream American English (MAE)-learning children on these same measures provided the data to select assessments for which (1) TD MAE and AAE children performed the same, and (2) TD performance was reliably different from LI performance in both dialect groups.
Theoretical Studies of Liquid He-4 Near the Superfluid Transition
NASA Technical Reports Server (NTRS)
Manousakis, Efstratios
2002-01-01
We performed theoretical studies of liquid helium by applying state of the art simulation and finite-size scaling techniques. We calculated universal scaling functions for the specific heat and superfluid density for various confining geometries relevant for experiments such as the confined helium experiment and other ground based studies. We also studied microscopically how the substrate imposes a boundary condition on the superfluid order parameter as the superfluid film grows layer by layer. Using path-integral Monte Carlo, a quantum Monte Carlo simulation method, we investigated the rich phase diagram of helium monolayer, bilayer and multilayer on a substrate such as graphite. We find excellent agreement with the experimental results using no free parameters. Finally, we carried out preliminary calculations of transport coefficients such as the thermal conductivity for bulk or confined helium systems and of their scaling properties. All our studies provide theoretical support for various experimental studies in microgravity.
The theoretical cognitive process of visualization for science education.
Mnguni, Lindelani E
2014-01-01
The use of visual models such as pictures, diagrams and animations in science education is increasing. This is because of the complex nature associated with the concepts in the field. Students, especially entrant students, often report misconceptions and learning difficulties associated with various concepts especially those that exist at a microscopic level, such as DNA, the gene and meiosis as well as those that exist in relatively large time scales such as evolution. However the role of visual literacy in the construction of knowledge in science education has not been investigated much. This article explores the theoretical process of visualization answering the question "how can visual literacy be understood based on the theoretical cognitive process of visualization in order to inform the understanding, teaching and studying of visual literacy in science education?" Based on various theories on cognitive processes during learning for science and general education the author argues that the theoretical process of visualization consists of three stages, namely, Internalization of Visual Models, Conceptualization of Visual Models and Externalization of Visual Models. The application of this theoretical cognitive process of visualization and the stages of visualization in science education are discussed.
An Analysis of Machine- and Human-Analytics in Classification.
Tam, Gary K L; Kothari, Vivek; Chen, Min
2017-01-01
In this work, we present a study that traces the technical and cognitive processes in two visual analytics applications to a common theoretic model of soft knowledge that may be added into a visual analytics process for constructing a decision-tree model. Both case studies involved the development of classification models based on the "bag of features" approach. Both compared a visual analytics approach using parallel coordinates with a machine-learning approach using information theory. Both found that the visual analytics approach had some advantages over the machine learning approach, especially when sparse datasets were used as the ground truth. We examine various possible factors that may have contributed to such advantages, and collect empirical evidence for supporting the observation and reasoning of these factors. We propose an information-theoretic model as a common theoretic basis to explain the phenomena exhibited in these two case studies. Together we provide interconnected empirical and theoretical evidence to support the usefulness of visual analytics.
Theoretical study of a dual harmonic system and its application to the CSNS/RCS
NASA Astrophysics Data System (ADS)
Yuan, Yao-Shuo; Wang, Na; Xu, Shou-Yan; Yuan, Yue; Wang, Sheng
2015-12-01
Dual harmonic systems have been widely used in high intensity proton synchrotrons to suppress the space charge effect, as well as reduce the beam loss. To investigate the longitudinal beam dynamics in a dual rf system, the potential well, the sub-buckets in the bunch and the multi-solutions of the phase equation are studied theoretically in this paper. Based on these theoretical studies, optimization of bunching factor and rf voltage waveform are made for the dual harmonic rf system in the upgrade phase of the China Spallation Neutron Source Rapid Cycling Synchrotron (CSNS/RCS). In the optimization process, the simulation with space charge effect is done using a newly developed code, C-SCSIM. Supported by National Natural Science Foundation of China (11175193)
Zullig, Leah L.; Melnyk, S. Dee; Stechuchak, Karen M.; McCant, Felicia; Danus, Susanne; Oddone, Eugene; Bastian, Lori; Olsen, Maren; Edelman, David; Rakley, Susan; Morey, Miriam
2014-01-01
Abstract Background: Hypertension, hyperlipidemia, and diabetes are significant, but often preventable, contributors to cardiovascular disease (CVD) risk. Medication and behavioral nonadherence are significant barriers to successful hypertension, hyperlidemia, and diabetes management. Our objective was to describe the theoretical framework underlying a tailored behavioral and educational pharmacist-administered intervention for achieving CVD risk reduction. Materials and Methods: Adults with poorly controlled hypertension and/or hyperlipidemia were enrolled from three outpatient primary care clinics associated with the Durham Veterans Affairs Medical Center (Durham, NC). Participants were randomly assigned to receive a pharmacist-administered, tailored, 1-year telephone-based intervention or usual care. The goal of the study was to reduce the risk for CVD through a theory-driven intervention to increase medication adherence and improve health behaviors. Results: Enrollment began in November 2011 and is ongoing. The target sample size is 500 patients. Conclusions: The Cardiovascular Intervention Improvement Telemedicine Study (CITIES) intervention has been designed with a strong theoretical underpinning. The theoretical foundation and intervention are designed to encourage patients with multiple comorbidities and poorly controlled CVD risk factors to engage in home-based monitoring and tailored telephone-based interventions. Evidence suggests that clinical pharmacist-administered telephone-based interventions may be efficiently integrated into primary care for patients with poorly controlled CVD risk factors. PMID:24303930
Explaining the use of text-based communication media: an examination of three theories of media use.
Park, Namkee; Chung, Jae Eun; Lee, Seungyoon
2012-07-01
The present study examined the factors associated with individuals' use of three different text-based communication media: e-mail, cell-phone texting, and Facebook Wall postings. Three theoretical perspectives, including media richness theory, uses and gratifications, and perceived network effects, were examined. Using data from a survey of college students (N=280), the study found that the theoretical constructs from these theories play different roles when applied to different technologies. The results suggest that a simultaneous consideration of technological attributes, users' motivations, and social circumstances in which users select and use the technology is useful for fully understanding the dynamics of the selection and the use of a given technology.
Game Theoretic Resolution of Water Conflicts
NASA Astrophysics Data System (ADS)
Tyagi, H.; Gosain, A. K.; Khosa, R.
2017-12-01
Water disputes are of multi-disciplinary nature and involve an array of natural, hydrological,social, political and economic issues. Operations Research based decision making methodshave been found to facilitate mathematical analysis of such multifaceted problems thatconsist of multiple stakeholders and their conflicting objectives. Game Theoretic techniqueslike Metagame and Hypergame Analysis can provide a framework for conceptualizing waterconflicts and envisaging their potential solutions. In the present research, firstly a Metagamemodel has been developed to identify range of plausible equilibrium outcomes for resolvingconflicts pertaining to water apportionments in a transboundary watercourse. Further, it hasbeen observed that the contenders often hide their strategies from other players to getfavorable water allocations. Consequently, there are widespread misinterpretations about thetactics of the competitors and contenders have to formulate their strategies entirely based ontheir perception about others. Accordingly, a Hypergame study has also been conducted tomodel the probable misperceptions that may exist amongst the river riparians. Thus, thecurrent study assesses the efficacy of Game Theoretic techniques as possible redressalmechanism for water conflicts.
An experimental and theoretical study of reaction mechanisms between nitriles and hydroxylamine.
Vörös, Attila; Mucsi, Zoltán; Baán, Zoltán; Timári, Géza; Hermecz, István; Mizsey, Péter; Finta, Zoltán
2014-10-28
The industrially relevant reaction between nitriles and hydroxylamine yielding amidoximes was studied in different molecular solvents and in ionic liquids. In industry, this procedure is carried out on the ton scale in alcohol solutions and the above transformation produces a significant amount of unexpected amide by-product, depending on the nature of the nitrile, which can cause further analytical and purification issues. Although there were earlier attempts to propose mechanisms for this transformation, the real reaction pathway is still under discussion. A new detailed reaction mechanistic explanation, based on theoretical and experimental proof, is given to augment the former mechanisms, which allowed us to find a more efficient, side-product free procedure. Interpreting the theoretical results obtained, it was shown that the application of specific imidazolium, phosphonium and quaternary ammonium based ionic liquids could decrease simultaneously the reaction time while eliminating the amide side-product, leading to the targeted product selectively. This robust and economic procedure now affords a fast, selective amide free synthesis of amidoximes.
Hochlaf, Majdi; Pan, Yi; Lau, Kai-Chung; Majdi, Youssef; Poisson, Lionel; Garcia, Gustavo A; Nahon, Laurent; Al Mogren, Muneerah Mogren; Schwell, Martin
2015-02-19
For fully understanding the light-molecule interaction dynamics at short time scales, recent theoretical and experimental studies proved the importance of accurate characterizations not only of the ground (D0) but also of the electronic excited states (e.g., D1) of molecules. While ground state investigations are currently straightforward, those of electronic excited states are not. Here, we characterized the à electronic state of ionic thymine (T(+)) DNA base using explicitly correlated coupled cluster ab initio methods and state-of-the-art synchrotron-based electron/ion coincidence techniques. The experimental spectrum is composed of rich and long vibrational progressions corresponding to the population of the low frequency modes of T(+)(Ã). This work challenges previous numerous works carried out on DNA bases using common synchrotron and VUV-based photoelectron spectroscopies. We provide hence a powerful theoretical and experimental framework to study the electronic structure of ionized DNA bases that could be generalized to other medium-sized biologically relevant systems.
ERIC Educational Resources Information Center
Nicholls, Emma; Walsh, Margaret
2007-01-01
Purpose: This case study aims to provide a critical evaluation of the decision by the University of Wolverhampton's School of Legal Studies to develop a number of work-based learning modules, offered as part of the undergraduate programme. It seeks to examine why the School has taken the approach of embedding work-based learning into what has…
Problem-based learning in optical engineering studies
NASA Astrophysics Data System (ADS)
Voznesenskaya, Anna
2016-09-01
Nowadays, the Problem-Based Learning (PBL) is one of the most prospective educational technologies. PBL is based on evaluation of learning outcomes of a student, both professional and personal, instead of traditional evaluation of theoretical knowledge and selective practical skills. Such an approach requires changes in the curricula development. There should be introduced projects (cases) imitating real tasks from the professional life. These cases should include a problem summary with necessary theoretic description, charts, graphs, information sources etc, task to implement and evaluation indicators and criteria. Often these cases are evaluated with the assessment-center method. To motivate students for the given task they could be divided into groups and have a contest. Whilst it looks easy to implement in social, economic or teaching fields PBL is pretty complicated in engineering studies. Examples of cases in the first-cycle optical engineering studies are shown in this paper. Procedures of the PBL implementation and evaluation are described.
Border and surface tracing--theoretical foundations.
Brimkov, Valentin E; Klette, Reinhard
2008-04-01
In this paper we define and study digital manifolds of arbitrary dimension, and provide (in particular)a general theoretical basis for curve or surface tracing in picture analysis. The studies involve properties such as one-dimensionality of digital curves and (n-1)-dimensionality of digital hypersurfaces that makes them discrete analogs of corresponding notions in continuous topology. The presented approach is fully based on the concept of adjacency relation and complements the concept of dimension as common in combinatorial topology. This work appears to be the first one on digital manifolds based ona graph-theoretical definition of dimension. In particular, in the n-dimensional digital space, a digital curve is a one-dimensional object and a digital hypersurface is an (n-1)-dimensional object, as it is in the case of curves and hypersurfaces in the Euclidean space. Relying on the obtained properties of digital hypersurfaces, we propose a uniform approach for studying good pairs defined by separations and obtain a classification of good pairs in arbitrary dimension. We also discuss possible applications of the presented definitions and results.
Gómez-Coca, Silvia; Ruiz, Eliseo
2012-03-07
The magnetic properties of a new family of single-molecule magnet Ni(3)Mn(2) complexes were studied using theoretical methods based on Density Functional Theory (DFT). The first part of this study is devoted to analysing the exchange coupling constants, focusing on the intramolecular as well as the intermolecular interactions. The calculated intramolecular J values were in excellent agreement with the experimental data, which show that all the couplings are ferromagnetic, leading to an S = 7 ground state. The intermolecular interactions were investigated because the two complexes studied do not show tunnelling at zero magnetic field. Usually, this exchange-biased quantum tunnelling is attributed to the presence of intermolecular interactions calculated with the help of theoretical methods. The results indicate the presence of weak intermolecular antiferromagnetic couplings that cannot explain the ferromagnetic value found experimentally for one of the systems. In the second part, the goal is to analyse magnetic anisotropy through the calculation of the zero-field splitting parameters (D and E), using DFT methods including the spin-orbit effect.
Voga, G P; Coelho, M G; de Lima, G M; Belchior, J C
2011-04-07
In this paper we report experimental and theoretical studies concerning the thermal behavior of some organotin-Ti(IV) oxides employed as precursors for TiO(2)/SnO(2) semiconducting based composites, with photocatalytic properties. The organotin-TiO(2) supported materials were obtained by chemical reactions of SnBu(3)Cl (Bu = butyl), TiCl(4) with NH(4)OH in ethanol, in order to impregnate organotin oxide in a TiO(2) matrix. A theoretical model was developed to support experimental procedures. The kinetics parameters: frequency factor (A), activation energy, and reaction order (n) can be estimated through artificial intelligence methods. Genetic algorithm, fuzzy logic, and Petri neural nets were used in order to determine the kinetic parameters as a function of temperature. With this in mind, three precursors were prepared in order to obtain composites with Sn/TiO(2) ratios of 0% (1), 15% (2), and 30% (3) in weight, respectively. The thermal behavior of products (1-3) was studied by thermogravimetric experiments in oxygen.
Study on some useful Operators for Graph-theoretic Image Processing
NASA Astrophysics Data System (ADS)
Moghani, Ali; Nasiri, Parviz
2010-11-01
In this paper we describe a human perception based approach to pixel color segmentation which applied in color reconstruction by numerical method associated with graph-theoretic image processing algorithm typically in grayscale. Fuzzy sets defined on the Hue, Saturation and Value components of the HSV color space, provide a fuzzy logic model that aims to follow the human intuition of color classification.
Vaughan-Graham, Julie; Cott, Cheryl; Wright, F Virginia
2015-01-01
The study's purpose was to describe the range of knowledge pertaining to the Bobath (NDT) concept in adult neurological rehabilitation, synthesizes the findings, identify knowledge gaps and develop empirically based recommendations for future research. A scoping review of research and non-research articles published from 2007 to 2012. Two independent reviewers selected studies based on a systematic procedure. Inclusion criteria for studies were electronically accessible English language literature with Bobath and/or Neurodevelopmental Therapy as the subject heading in the title/keyword/abstract/intervention comparison with respect to adult neurological conditions. Data were abstracted and summarized with respect to study design, theoretical framework, clinical application including population representation, study fidelity, intervention comparison, duration of care, measurement and findings. Of the 33 publications identified 17 were intervention studies (11 RCT's/1 prospective parallel group design/5 N-of-1). One other paper was a systematic review. The intervention studies, primarily RCT designs, have serious methodological concerns particularly related to study/treatment fidelity and measurement resulting in no clear clinical direction. Aspects such as theoretical framework, therapist skill, quality of movement measurement and individualized interventions require careful consideration in the design of Bobath studies. Implications for Rehabilitation Future intervention studies should be based on the current Bobath theoretical framework and key aspects of clinical practice. Study and treatment fidelity issues need to be carefully considered when interpreting the results of existing RCT's evaluating the Bobath concept. N-of-1 randomized, observational, factorial and mixed method study designs should be considered as alternative study options.
ERIC Educational Resources Information Center
Marulcu, Ismail
2010-01-01
This mixed method study examined the impact of a LEGO-based, engineering-oriented curriculum compared to an inquiry-based curriculum on fifth graders' content learning of simple machines. This study takes a social constructivist theoretical stance that science learning involves learning scientific concepts and their relations to each other. From…
Play-Based Art Activities in Early Years: Teachers' Thinking and Practice
ERIC Educational Resources Information Center
Savva, Andri; Erakleous, Valentina
2018-01-01
The present study reports findings on pre-service teachers' thinking during planning and implementing play-based art activities. "Thinking" (in the present study) is informed by discourses emphasising art teaching and learning in relation to play and theoretical assumptions conceptualising planning as "practice of knowing."…
Theory to Reality: A Few Issues in Implementing Problem-Based Learning
ERIC Educational Resources Information Center
Hung, Woei
2011-01-01
The success of an intervention depends not only upon its theoretical soundness, but also on proper implementation that reflects the guidelines derived from its theoretical conception. Debates surrounding the effectiveness of problem-based learning (PBL) have focused on its theoretical conception and students' learning outcomes, but implementation…
Recent progress in the theoretical modelling of Cepheids and RR Lyrae stars
NASA Astrophysics Data System (ADS)
Marconi, Marcella
2017-09-01
Cepheids and RR Lyrae are among the most important primary distance indicators to calibrate the extragalactic distance ladder and excellent stellar population tracers, for Population I and Population II, respectively. In this paper I first mention some recent theoretical studies of Cepheids and RR Lyrae obtained with different theoretical tools. Then I focus the attention on new results based on nonlinear convective pulsation models in the context of some international projects, including VMC@VISTA and the Gaia collaboration. The open problems for both Cepheids and RR Lyrae are briefly discussed together with some challenging future application.
Valente, Marco A. G.; Teixeira, Deiver A.; Azevedo, David L.; Feliciano, Gustavo T.; Benedetti, Assis V.; Fugivara, Cecílio S.
2017-01-01
The interaction of volatile corrosion inhibitors (VCI), caprylate salt derivatives from amines, with zinc metallic surfaces is assessed by density functional theory (DFT) computer simulations, electrochemical impedance (EIS) measurements and humid chamber tests. The results obtained by the different methods were compared, and linear correlations were obtained between theoretical and experimental data. The correlations between experimental and theoretical results showed that the molecular size is the determining factor in the inhibition efficiency. The models used and experimental results indicated that dicyclohexylamine caprylate is the most efficient inhibitor. PMID:28620602
Head, Katharine J; Noar, Seth M
2014-01-01
This paper explores the question: what are barriers to health behaviour theory development and modification, and what potential solutions can be proposed? Using the reasoned action approach (RAA) as a case study, four areas of theory development were examined: (1) the theoretical domain of a theory; (2) tension between generalisability and utility, (3) criteria for adding/removing variables in a theory, and (4) organisational tracking of theoretical developments and formal changes to theory. Based on a discussion of these four issues, recommendations for theory development are presented, including: (1) the theoretical domain for theories such as RAA should be clarified; (2) when there is tension between generalisability and utility, utility should be given preference given the applied nature of the health behaviour field; (3) variables should be formally removed/amended/added to a theory based on their performance across multiple studies and (4) organisations and researchers with a stake in particular health areas may be best suited for tracking the literature on behaviour-specific theories and making refinements to theory, based on a consensus approach. Overall, enhancing research in this area can provide important insights for more accurately understanding health behaviours and thus producing work that leads to more effective health behaviour change interventions.
NASA Astrophysics Data System (ADS)
Yang, Shuai; Wu, Wei; Wang, Xingshu; Xu, Zhiguang
2018-01-01
The coupling error in the measurement of ship hull deformation can significantly influence the attitude accuracy of the shipborne weapons and equipments. It is therefore important to study the characteristics of the coupling error. In this paper, an comprehensive investigation on the coupling error is reported, which has a potential of deducting the coupling error in the future. Firstly, the causes and characteristics of the coupling error are analyzed theoretically based on the basic theory of measuring ship deformation. Then, simulations are conducted for verifying the correctness of the theoretical analysis. Simulation results show that the cross-correlation between dynamic flexure and ship angular motion leads to the coupling error in measuring ship deformation, and coupling error increases with the correlation value between them. All the simulation results coincide with the theoretical analysis.
Management by Results at Finnish Universities
ERIC Educational Resources Information Center
Kuoppala, Kari
2005-01-01
The funding of Finnish Universities has been based on a "management by results" strategy since 1991. This paper analyses the effects of this strategy on university management and administration. Empirically the study is based on material collected from four multidisciplinary universities. Theoretically it is based on organization theory…
NASA Astrophysics Data System (ADS)
Zhang, Xiangling
The fundamental objective of the present study is to improve our understanding of audible sound propagation in the pulmonary system and torso. A related applied objective is to assess the feasibility of using audible acoustics for diagnosis of specific pulmonary conditions, such as pneumothorax (PTX). To accomplish these objectives, this study includes theoretical, computational and experimental developments aimed at: (1) better identifying the mechanical dynamic properties of soft biological tissues found in the torso region, (2) investigating the mechanisms of sound attenuation that occur when a PTX is present using greatly simplified theoretical and computational models, and (3) exploring the feasibility and utility of more comprehensive and precise computational finite element models of audible sound propagation in the pulmonary system and torso that would aid in related diagnostic developments. Mechanical material properties of soft biological tissue are studied for the low audible frequency range. The sensitivity to shear viscoelastic material constants of theoretical solutions for radiation impedance and surface wave motion are compared. Theoretical solutions are also compared to experimental measurements and numerical results from finite element analysis. It is found that, while prior theoretical solutions for radiation impedance are accurate, use of such measurements to estimate shear viscoelastic constants is not as precise as the use of surface wave measurements. The feasibility of using audible sound for diagnosis of pneumothorax is studied. Simplified one- and two-dimensional theoretical and numerical models of sound transmission through the pulmonary system and chest region to the chest wall surface are developed to more clearly understand the mechanism of energy loss when a pneumothorax is present, relative to a baseline case. A canine study on which these models are based predicts significant decreases in acoustic transmission strength when a pneumothorax is presented, in qualitative agreement with experimental measurements in dogs. Finally, the feasibility of building three-dimensional computational models is studied based on CT images of human subject or combination of the Horsfield airway model with geometry of other parts approximate from medical illustration. Preliminary results from these models show the same trend of acoustic energy loss when a PTX is present.
Innovation value chain capability in Malaysian-owned company: A theoretical framework
NASA Astrophysics Data System (ADS)
Abidin, Norkisme Zainal; Suradi, Nur Riza Mohd
2014-09-01
Good quality products or services are no longer adequate to guarantee the sustainability of a company in the present competitive business. Prior research has developed various innovation models with the hope to better understand the innovativeness of the company. Due to countless definitions, indicators, factors, parameter and approaches in the study of innovation, it is difficult to ensure which one will best suit the Malaysian-owned company innovativeness. This paper aims to provide a theoretical background to support the framework of the innovation value chain capability in Malaysian-owned Company. The theoretical framework was based on the literature reviews, expert interviews and focus group study. The framework will be used to predict and assess the innovation value chain capability in Malaysian-owned company.
Vertical distribution of microphysical properties in radiation fogs - A case study
NASA Astrophysics Data System (ADS)
Egli, S.; Maier, F.; Bendix, J.; Thies, B.
2015-01-01
The present study investigates the validity of a theoretical liquid water content (LWC) profile in fog layers currently used for satellite based ground fog detection, with a special focus on the temporal dynamics during fog life cycle. For this purpose, LWC profiles recorded during two different fog events by means of a tethered balloon borne measurement system are presented and discussed. The results indicate a good agreement in trend and gradient between measured and theoretical LWC profiles during the mature stage of the fog life cycle. The profile obtained during the dissipation stage shows less accordance with the theoretical profile. To improve the agreement between theoretical and measured LWC profiles, the evolutionary stages during the fog life cycle should be incorporated. However, the variability within the prenoted measurements points out that more LWC profiles during a great variety of different fog events have to be collected for a well-justified adaptation of the theoretical LWC profile, considering fog life cycle phases in the future. In general, this underlines the existing knowledge gap regarding the vertical distribution of microphysical properties in natural fogs.
Photonics and spectroscopy in nanojunctions: a theoretical insight
Galperin, Michael
2017-04-11
The progress of experimental techniques at the nanoscale in the last decade made optical measurements in current-carrying nanojunctions a reality, thus indicating the emergence of a new field of research coined optoelectronics. Optical spectroscopy of open nonequilibrium systems is a natural meeting point for (at least) two research areas: nonlinear optical spectroscopy and quantum transport, each with its own theoretical toolbox. We review recent progress in the field comparing theoretical treatments of optical response in nanojunctions as is accepted in nonlinear spectroscopy and quantum transport communities. A unified theoretical description of spectroscopy in nanojunctions is presented. Here, we argue thatmore » theoretical approaches of the quantum transport community (and in particular, the Green function based considerations) yield a convenient tool for optoelectronics when the radiation field is treated classically, and that differences between the toolboxes may become critical when studying the quantum radiation field in junctions.« less
Experimental and theoretical IR and Raman spectra of picolinic, nicotinic and isonicotinic acids
NASA Astrophysics Data System (ADS)
Koczoń, P.; Dobrowolski, J. Cz.; Lewandowski, W.; Mazurek, A. P.
2003-07-01
The experimental and theoretical (B3PW91/6-311++G**) vibrational (IR and Raman) spectra of picolinic, nicotinic and isonicotinic acids (pyridine-2-, -3-, and -4-carboxylic acid, respectively) were studied. Three stable calculated structures were found for picolinic acid: the structure with intramolecular hydrogen COOH⋯N bond, and the two without hydrogen bond. For the nicotinic acid two stable theoretical structures differ in orientation of the COOH group with respect to the nitrogen atom, whereas for the isonicotinic acid only one form was stable. The theoretical vibrational spectra of the three acids were interpreted by means of potential energy distributions (PEDs) using VEDA 3 program. Next, selected experimental bands were assigned based on the scaled theoretical wavenumbers. Finally, the wavenumbers and intensities for the three isomeric acids were compared and discussed in terms of location of the carboxylic group.
Can Interactive Web-Based CAD Tools Improve the Learning of Engineering Drawing? A Case Study
ERIC Educational Resources Information Center
Pando Cerra, Pablo; Suárez González, Jesús M.; Busto Parra, Bernardo; Rodríguez Ortiz, Diana; Álvarez Peñín, Pedro I.
2014-01-01
Many current Web-based learning environments facilitate the theoretical teaching of a subject but this may not be sufficient for those disciplines that require a significant use of graphic mechanisms to resolve problems. This research study looks at the use of an environment that can help students learn engineering drawing with Web-based CAD…
Theoretical Investigation of oxides for batteries and fuel cell applications
NASA Astrophysics Data System (ADS)
Ganesh, Panchapakesan; Lubimtsev, Andrew A.; Balachandran, Janakiraman
I will present theoretical studies of Li-ion and proton-conducting oxides using a combination of theory and computations that involve Density Functional Theory based atomistic modeling, cluster-expansion based studies, global optimization, high-throughput computations and machine learning based investigation of ionic transport in oxide materials. In Li-ion intercalated oxides, we explain the experimentally observed (Nature Materials 12, 518-522 (2013)) 'intercalation pseudocapacitance' phenomenon, and explain why Nb2O5 is special to show this behavior when Li-ions are intercalated (J. Mater. Chem. A, 2013,1, 14951-14956), but not when Na-ions are used. In addition, we explore Li-ion intercalation theoretically in VO2 (B) phase, which is somewhat structurally similar to Nb2O5 and predict an interesting role of site-trapping on the voltage and capacity of the material, validated by ongoing experiments. Computations of proton conducting oxides explain why Y-doped BaZrO3 , one of the fastest proton conducting oxide, shows a decrease in conductivity above 20% Y-doping. Further, using high throughput computations and machine learning tools we discover general principles to improve proton conductivity. Acknowledgements: LDRD at ORNL and CNMS at ORNL
Theoretical investigation on multilayer nanocomposite-based fiber optic SPR sensor
NASA Astrophysics Data System (ADS)
Shojaie, Ehsan; Madanipour, Khosro; Gharibzadeh, Azadeh; Abbasi, Shabnam
2017-06-01
In this work, a multilayer nanocomposite based fiber optic SPR sensor is considered and especially designed for CO2 gas detection. This proposed fiber sensor consists of fiber core, gold-silver alloy and the absorber layers. The investigation is based on the evaluation of the transmitted-power derived under the transfer matrix method and the multiple-reflection in the sensing area. In terms of sensitivity, the sensor performance is studied theoretically under various conditions related to the metal layer and its gold and silver nanoparticles to form a single alloy film. Effect of additional parameters such as the ratio of the alloy composition and the thickness of the alloy film on the performance of the SPR sensor is studied, as well. Finally, a four-layer structure is introduced to detect carbon dioxide gas. It contains core fiber, gold-silver alloy layer, an absorbent layer of carbon dioxide gas (KOH) and measurement environment. Lower price and size are the main advantages of using such a sensor in compare with commercial (NDIR) gas sensor. Theoretical results show by increasing the metal layer thickness the sensitivity of sensor is increased, and by increasing the ratio of the gold in alloy the sensitivity is decreased.
Changes in Teaching Efficacy during a Professional Development School-Based Science Methods Course
ERIC Educational Resources Information Center
Swars, Susan L.; Dooley, Caitlin McMunn
2010-01-01
This mixed methods study offers a theoretically grounded description of a field-based science methods course within a Professional Development School (PDS) model (i.e., PDS-based course). The preservice teachers' (n = 21) experiences within the PDS-based course prompted significant changes in their personal teaching efficacy, with the…
Re-Exploring Game-Assisted Learning Research: The Perspective of Learning Theoretical Bases
ERIC Educational Resources Information Center
Wu, Wen-Hsiung; Chiou, Wen-Bin; Kao, Hao-Yun; Hu, Chung-Hsing Alex; Huang, Sih-Han
2012-01-01
Previous literature reviews or meta-analysis based studies on game-assisted learning have provided important results, but few studies have considered the importance of learning theory, and coverage of papers after 2007 is scant. This study presents a systematic review of the literature using a meta-analysis approach to provide a more comprehensive…
ERIC Educational Resources Information Center
Tisdell, Elizabeth J.; Taylor, Edward W.; Forte, Karin Sprow
2013-01-01
This article presents the findings related to teaching beliefs and pedagogical practices of a study that examined how financial literacy educators educate adults from underserved population groups in community-based settings. The study is theoretically framed in the teaching beliefs and culturally responsive education literature. Findings reveal a…
A Gendered Lifestyle-Routine Activity Approach to Explaining Stalking Victimization in Canada.
Reyns, Bradford W; Henson, Billy; Fisher, Bonnie S; Fox, Kathleen A; Nobles, Matt R
2016-05-01
Research into stalking victimization has proliferated over the last two decades, but several research questions related to victimization risk remain unanswered. Accordingly, the present study utilized a lifestyle-routine activity theoretical perspective to identify risk factors for victimization. Gender-based theoretical models also were estimated to assess the possible moderating effects of gender on the relationship between lifestyle-routine activity concepts and victimization risk. Based on an analysis of a representative sample of more than 15,000 residents of Canada from the Canadian General Social Survey (GSS), results suggested conditional support for lifestyle-routine activity theory and for the hypothesis that predictors of stalking victimization may be gender based. © The Author(s) 2015.
Human factors in operations design
NASA Technical Reports Server (NTRS)
Chafin, R. L.
1982-01-01
The manner in which organizations develop their organizational structure is considered, taking into account an example in which the environment changes for an older organization. In such cases, it would be preferable to have some theoretical foundation on which to base the restructuring of the organization to meet new environmental needs. A description is given of a theoretic foundation based on the principles of Differentiation/Integration and Procedural/Knowledge based operations. The organizational design principle of Differentiation and Integration has been presented by Lawrence and Lorsch (1969). The differentiation/integration processes are related to the organizational structures presented in studies concerning NASA Deep Space Network (DSN) operations. The principles presented provide valuable tools for analyzing operations organization.
NASA Astrophysics Data System (ADS)
Karakurt, Tuncay; Cukurovali, Alaaddin; Subasi, Nuriye Tuna; Onaran, Abdurrahman; Ece, Abdulilah; Eker, Sıtkı; Kani, Ibrahim
2018-02-01
In the present study, a single crystal of a Schiff base, 2,2‧(hydrazine-1,2-diylidenebis(propan-1-yl-1-ylidene))diphenol, was synthesized. The structure of the synthesized crystal was confirmed by 1H and 13C NMR spectroscopic and X-ray diffraction analysis techniques. Experimental and theoretical studies were carried out on two tautomeric structures. It has been observed that the title compound studied can be in two different tautomeric forms, phenol-imine and keto-amine. Theoretical calculations have been performed to support experimental results. Accordingly, the geometric parameters of the compound were optimized by the density functional theory (DFT) method using the Gaussian 09 and Quantum Espresso (QE) packet program was used for periodic boundary conditions (PBC) studies. Furthermore, the compound was also tested for in vitro antifungal activity against Sclerotinia sclerotiorum, Alternaria solani, Fusarium oxysporum f. sp. lycopersici and Monilinia fructigena plant pathogens. Promising inhibition profiles were observed especially towards A. solani. Finally, molecular docking studies and post-docking procedure based on Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) were also carried out to get insight into the compound's binding interactions with the potential. Although theoretical calculations showed that the phenol-imine form was more stable, keto-amine form was predicted to have better binding affinity which was concluded to result from loss of rotational entropy in phenol-imine upon binding. The results obtained here from both experimental and computational methods might serve as a potential lead in the development of novel anti-fungal agents.
A theoretical study of microwave beam absorption by a rectenna
NASA Technical Reports Server (NTRS)
Ott, J. H.; Rice, J. S.; Thorn, D. C.
1980-01-01
The rectenna's microwave power beam absorption limit was theoretically confirmed by two mathematical models descriptive of the microwave absorption process; first one model was based on the current sheet equivalency of a large planar array above a reflector and the second model, which was based on the properties of a waveguide with special imaging characteristics, quantified the electromagnetic modes (field configurations) in the immediate vicinity of a Rectenna element spacing which permit total power beam absorption by preventing unwanted modes from propagating (scattering) were derived using these models. Several factors causing unwanted scattering are discussed.
Evidence-based ergonomics. A comparison of Japanese and American office layouts.
Noro, Kageyu; Fujimaki, Goroh; Kishi, Shinsuke
2003-01-01
There is a variety of alternatives in office layouts. Yet the theoretical basis and criteria for predicting how well these layouts accommodate employees are poorly understood. The objective of this study was to evaluate criteria for selecting office layouts. Intensive computer workers worked in simulated office layouts in a controlled experimental laboratory. Eye movement measures indicate that knowledge work requires both concentration and interaction. Findings pointed to one layout as providing optimum balance between these 2 requirements. Recommendations for establishing a theoretical basis and design criteria for selecting office layouts based on work style are suggested.
Shaban, Ramon Z; Considine, Julie; Fry, Margaret; Curtis, Kate
2017-02-01
Generating knowledge through quality research is fundamental to the advancement of professional practice in emergency nursing and care. There are multiple paradigms, designs and methods available to researchers to respond to challenges in clinical practice. Systematic reviews, randomised control trials and other forms of experimental research are deemed the gold standard of evidence, but there are comparatively few such trials in emergency care. In some instances it is not possible or appropriate to undertake experimental research. When exploring new or emerging problems where there is limited evidence available, non-experimental methods are required and appropriate. This paper provides the theoretical foundations and an exemplar of the use of case study and case-based research to explore a new and emerging problem in the context of emergency care. It examines pre-hospital clinical judgement and decision-making of mental illness by paramedics. Using an exemplar the paper explores the theoretical foundations and conceptual frameworks of case study, it explains how cases are defined and the role researcher in this form of inquiry, it details important principles and the procedures for data gathering and analysis, and it demonstrates techniques to enhance trustworthiness and credibility of the research. Moreover, it provides theoretically and practical insights into using case study in emergency care. Copyright © 2017 College of Emergency Nursing Australasia. Published by Elsevier Ltd. All rights reserved.
Nakao, Takashi; Ohira, Hideki; Northoff, Georg
2012-01-01
Most experimental studies of decision-making have specifically examined situations in which a single less-predictable correct answer exists (externally guided decision-making under uncertainty). Along with such externally guided decision-making, there are instances of decision-making in which no correct answer based on external circumstances is available for the subject (internally guided decision-making). Such decisions are usually made in the context of moral decision-making as well as in preference judgment, where the answer depends on the subject’s own, i.e., internal, preferences rather than on external, i.e., circumstantial, criteria. The neuronal and psychological mechanisms that allow guidance of decisions based on more internally oriented criteria in the absence of external ones remain unclear. This study was undertaken to compare decision-making of these two kinds empirically and theoretically. First, we reviewed studies of decision-making to clarify experimental–operational differences between externally guided and internally guided decision-making. Second, using multi-level kernel density analysis, a whole-brain-based quantitative meta-analysis of neuroimaging studies was performed. Our meta-analysis revealed that the neural network used predominantly for internally guided decision-making differs from that for externally guided decision-making under uncertainty. This result suggests that studying only externally guided decision-making under uncertainty is insufficient to account for decision-making processes in the brain. Finally, based on the review and results of the meta-analysis, we discuss the differences and relations between decision-making of these two types in terms of their operational, neuronal, and theoretical characteristics. PMID:22403525
NASA Astrophysics Data System (ADS)
Mo, Yuxiang; Gao, Shuming; Dai, Zuyang; Li, Hua
2013-06-01
We report a combined experimental and theoretical study on the vibronic structure of CH_3F^+. The results show that the tunneling splittings of vibrational energy levels occur in CH_3F^+ due to the Jahn-Teller effect. Experimentally, we have measured a high resolution ZEKE spectrum of CH_3F up to 3500 cm^-^1 above the ground state. Theoretically, we performed an ab initio calculation based on the diabatic model. The adiabatic potential energy surfaces (APES) of CH_3F^+ have been calculated at the MRCI/CAS/avq(t)z level and expressed by Taylor expansions with normal coordinates as variables. The energy gradients for the lower and upper APES, the derivative couplings between them and also the energies of the APES have been used to determine the coefficients in the Taylor expansion. The spin-vibronic energy levels have been calculated by accounting all six vibrational modes and their couplings. The experimental ZEKE spectra were assigned based on the theoretical calculations. W. Domcke, D. R. Yarkony, and H. Köpple (Eds.), Conical Intersections: Eletronic Structure, Dynamics and Spectroscopy (World Scientific, Singapore, 2004). M. S. Schuurman, D. E. Weinberg, and D. R. Yarkony, J. Chem. Phys. 127, 104309 (2007).
Elseman, Ahmed Mourtada; Shalan, Ahmed Esmail; Sajid, Sajid; Rashad, Mohamed Mohamed; Hassan, Ali Mostafa; Li, Meicheng
2018-04-11
Toxicity and chemical instability issues of halide perovskites based on organic-inorganic lead-containing materials still remain as the main drawbacks for perovskite solar cells (PSCs). Herein, we discuss the preparation of copper (Cu)-based hybrid materials, where we replace lead (Pb) with nontoxic Cu metal for lead-free PSCs, and investigate their potential toward solar cell applications based on experimental and theoretical studies. The formation of (CH 3 NH 3 ) 2 CuX 4 [(CH 3 NH 3 ) 2 CuCl 4 , (CH 3 NH 3 ) 2 CuCl 2 I 2 , and (CH 3 NH 3 ) 2 CuCl 2 Br 2 ] was discussed in details. Furthermore, it was found that chlorine (Cl - ) in the structure is critical for the stabilization of the formed compounds. Cu-based perovskite-like materials showed attractive absorbance features extended to the near-infrared range, with appropriate band gaps. Green photoluminescence of these materials was obtained because of Cu + ions. The power conversion efficiency was measured experimentally and estimated theoretically for different architectures of solar cell devices.
Work-Based Learning: A New Higher Education?
ERIC Educational Resources Information Center
Boud, David, Ed.; Solomon, Nicky, Ed.
This three-part book contains 16 chapters exploring work-based learning from a theoretical and case-study perspective in the United Kingdom. Part 1, Framing Work-based Learning, contains the following four chapters: "New Practices for New Times" (David Boud, Nicky Solomon, and Colin Symes); "Repositioning Universities and Work"…
Indium oxide based fiber optic SPR sensor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shukla, Sarika; Sharma, Navneet K., E-mail: navneetk.sharma@jiit.ac.in
2016-05-06
Surface plasmon resonance based fiber optic sensor using indium oxide layer is presented and theoretically studied. It has been found that with increase in thickness of indium oxide layer beyond 170 nm, the sensitivity of SPR sensor decreases. 170 nm thick indium oxide layer based SPR sensor holds maximum sensitivity.
Assessing Classism in Academic Settings
ERIC Educational Resources Information Center
Langhout, Regina Day; Rosselli, Francine; Feinstein, Jonathan
2007-01-01
The research described in this paper creates a behaviorally based measure that defines theoretically distinct domains of classism, assesses base rates within a college context, and examines how social class, race, and gender are related to classism. Participants of the study were college students at Hilltop University. A web-based survey was used…
ERIC Educational Resources Information Center
García, Amelia Molina; Lara, José Luis Horacio Andrade
2016-01-01
In this paper we present some thoughts on the epistemological framework of comparative studies in education. We present some concepts on the internationalization, globalization and inter-relation networks, based on Jürgen Schriewer, Immanuel Wallerstein, and Norbert Elias's theoretical concepts. These reflections were built within the framework of…
Dewey's Concept of Experience for Inquiry-Based Landscape Drawing during Field Studies
ERIC Educational Resources Information Center
Tillmann, Alexander; Albrecht, Volker; Wunderlich, Jürgen
2017-01-01
The epistemological and educational philosophy of John Dewey is used as a theoretical basis to analyze processes of knowledge construction during geographical field studies. The experience of landscape drawing as a method of inquiry and a starting point for research-based learning is empirically evaluated. The basic drawing skills are acquired…
Prospective Relationship between Social Cognitive Variables and Leisure Time Physical Activity
ERIC Educational Resources Information Center
Hortz, Brian; Winters, Eric; Grim, Melissa L.; Petosa, R. Lingyak
2017-01-01
Background: Evidence suggests that health promotion interventions that are based on behavioral theories are more effective than those lacking a theoretical base. Recent studies have begun to look at the relationship between social cognitive variables and physical activity in varied populations. Purpose: The purpose of this study is to determine…
Situationally Embodied Curriculum: Relating Formalisms and Contexts
ERIC Educational Resources Information Center
Barab, Sasha; Zuiker, Steve; Warren, Scott; Hickey, Dan; Ingram-Goble, Adam; Kwon, Eun-Ju; Kouper, Inna; Herring, Susan C.
2007-01-01
This study describes an example of design-based research in which we make theoretical improvements in our understanding, in part based on empirical work, and use these to revise our curriculum and, simultaneously, our evolving theory of the relations between contexts and disciplinary formalisms. Prior to this study, we completed a first cycle of…
Assessing Sensitivity of Early Head Start Study Findings to Manipulated Randomization Threats
ERIC Educational Resources Information Center
Green, Sheridan
2013-01-01
Increasing demands for design rigor and an emphasis on evidence-based practice on a national level indicated a need for further guidance related to successful implementation of randomized studies in education. Rigorous and meaningful experimental research and its conclusions help establish a valid theoretical and evidence base for educational…
Statistical Measures for Usage-Based Linguistics
ERIC Educational Resources Information Center
Gries, Stefan Th.; Ellis, Nick C.
2015-01-01
The advent of usage-/exemplar-based approaches has resulted in a major change in the theoretical landscape of linguistics, but also in the range of methodologies that are brought to bear on the study of language acquisition/learning, structure, and use. In particular, methods from corpus linguistics are now frequently used to study distributional…
An Empirical Typology of Residential Care/Assisted Living Based on a Four-State Study
ERIC Educational Resources Information Center
Park, Nan Sook; Zimmerman, Sheryl; Sloane, Philip D.; Gruber-Baldini, Ann L.; Eckert, J. Kevin
2006-01-01
Purpose: Residential care/assisted living describes diverse facilities providing non-nursing home care to a heterogeneous group of primarily elderly residents. This article derives typologies of assisted living based on theoretically and practically grounded evidence. Design and Methods: We obtained data from the Collaborative Studies of Long-Term…
Development of a Problem-Based Learning Matrix for Data Collection
ERIC Educational Resources Information Center
Sipes, Shannon M.
2017-01-01
Few of the papers published in journals and conference proceedings on problem-based learning (PBL) are empirical studies, and most of these use self-report as the measure of PBL (Beddoes, Jesiek, & Borrego, 2010). The current study provides a theoretically derived matrix for coding and classifying PBL that was objectively applied to official…
NASA Technical Reports Server (NTRS)
Xu, Tian-Bing; Su, Ji; Jiang, Xiaoning; Rehrig, Paul W.; Zhang, Shujun; Shrout, Thomas R.; Zhang, Qiming
2006-01-01
An electroactive polymer (EAP)-ceramic hybrid actuation system (HYBAS) was developed recently at NASA Langley Research Center. This paper focuses on the effect of the bending stiffness of the EAP component on the performance of a HYBAS, in which the actuation of the EAP element can match the theoretical prediction at various length/thickness ratios for a constant elastic modulus of the EAP component. The effects on the bending stiffness of the elastic modulus and length/thickness ratio of the EAP component were studied. A critical bending stiffness to keep the actuation of the EAP element suitable for a rigid beam theory-based modeling was found for electron irradiated P(VDF-TrFE) copolymer. For example, the agreement of experimental data and theoretical modeling for a HYBAS with the length/thickness ratio of EAP element at 375 times is demonstrated. However, the beam based theoretical modeling becomes invalid (i.e., the profile of the HYBAS movement does not follow the prediction of theoretical modeling) when the bending stiffness is lower than a critical value.
NASA Astrophysics Data System (ADS)
Lee, Tsung Hung; Jan, Fen-Hauh
2015-07-01
The scientific understanding of the recreation experience and the environmentally responsible behavior of nature-based tourists is limited. This study examines the relationship among the recreation experience, environmental attitude, biospheric value, and the general and site-specific environmentally responsible behavior of nature-based tourists in Taomi, Liuqiu Island, and Aowanda and Najenshan in Taiwan. A total of 1342 usable questionnaires were collected for this study. The empirical results indicate that the recreation experience influences biospheric value and environmental attitude; subsequently, it then indirectly influences the general and site-specific environmentally responsible behavior of nature-based tourists. Our theoretical behavioral model elucidates previously proposed but unexamined behavioral models among nature-based tourists, and it offers a theoretical framework for researchers, decision makers, managers, and tourists in the field of nature-based tourism. We conclude that when an individual participates in nature-based tourism as described here, these recreation experiences strengthen their environmental attitude and biospheric value, and consequently increase their engagement in both general and site-specific environmentally responsible behaviors.
Lee, Tsung Hung; Jan, Fen-Hauh
2015-07-01
The scientific understanding of the recreation experience and the environmentally responsible behavior of nature-based tourists is limited. This study examines the relationship among the recreation experience, environmental attitude, biospheric value, and the general and site-specific environmentally responsible behavior of nature-based tourists in Taomi, Liuqiu Island, and Aowanda and Najenshan in Taiwan. A total of 1342 usable questionnaires were collected for this study. The empirical results indicate that the recreation experience influences biospheric value and environmental attitude; subsequently, it then indirectly influences the general and site-specific environmentally responsible behavior of nature-based tourists. Our theoretical behavioral model elucidates previously proposed but unexamined behavioral models among nature-based tourists, and it offers a theoretical framework for researchers, decision makers, managers, and tourists in the field of nature-based tourism. We conclude that when an individual participates in nature-based tourism as described here, these recreation experiences strengthen their environmental attitude and biospheric value, and consequently increase their engagement in both general and site-specific environmentally responsible behaviors.
NASA Astrophysics Data System (ADS)
Desantes, J. M.; Salvador, F. J.; López, J. J.; de La Morena, J.
2011-02-01
In this paper, a research aimed at quantifying mass and momentum transfer in the near-nozzle field of diesel sprays injected into stagnant ambient air is reported. The study combines X-ray measurements for two different nozzles and axial positions, which provide mass distributions in the spray, with a theoretical model based on momentum flux conservation, which was previously validated. This investigation has allowed the validation of Gaussian profiles for local fuel concentration and velocity near the nozzle exit, as well as the determination of Schmidt number at realistic diesel spray conditions. This information could be very useful for those who are interested in spray modeling, especially at high-pressure injection conditions.
Rational design of new electrolyte materials for electrochemical double layer capacitors
NASA Astrophysics Data System (ADS)
Schütter, Christoph; Husch, Tamara; Viswanathan, Venkatasubramanian; Passerini, Stefano; Balducci, Andrea; Korth, Martin
2016-09-01
The development of new electrolytes is a centerpiece of many strategies to improve electrochemical double layer capacitor (EDLC) devices. We present here a computational screening-based rational design approach to find new electrolyte materials. As an example application, the known chemical space of almost 70 million compounds is investigated in search of electrochemically more stable solvents. Cyano esters are identified as especially promising new compound class. Theoretical predictions are validated with subsequent experimental studies on a selected case. These studies show that based on theoretical predictions only, a previously untested, but very well performing compound class was identified. We thus find that our rational design strategy is indeed able to successfully identify completely new materials with substantially improved properties.
Amemori, Masamitsu; Michie, Susan; Korhonen, Tellervo; Murtomaa, Heikki; Kinnunen, Taru H
2011-05-26
Tobacco use adversely affects oral health. Clinical guidelines recommend that dental providers promote tobacco abstinence and provide patients who use tobacco with brief tobacco use cessation counselling. Research shows that these guidelines are seldom implemented, however. To improve guideline adherence and to develop effective interventions, it is essential to understand provider behaviour and challenges to implementation. This study aimed to develop a theoretically informed measure for assessing among dental providers implementation difficulties related to tobacco use prevention and cessation (TUPAC) counselling guidelines, to evaluate those difficulties among a sample of dental providers, and to investigate a possible underlying structure of applied theoretical domains. A 35-item questionnaire was developed based on key theoretical domains relevant to the implementation behaviours of healthcare providers. Specific items were drawn mostly from the literature on TUPAC counselling studies of healthcare providers. The data were collected from dentists (n = 73) and dental hygienists (n = 22) in 36 dental clinics in Finland using a web-based survey. Of 95 providers, 73 participated (76.8%). We used Cronbach's alpha to ascertain the internal consistency of the questionnaire. Mean domain scores were calculated to assess different aspects of implementation difficulties and exploratory factor analysis to assess the theoretical domain structure. The authors agreed on the labels assigned to the factors on the basis of their component domains and the broader behavioural and theoretical literature. Internal consistency values for theoretical domains varied from 0.50 ('emotion') to 0.71 ('environmental context and resources'). The domain environmental context and resources had the lowest mean score (21.3%; 95% confidence interval [CI], 17.2 to 25.4) and was identified as a potential implementation difficulty. The domain emotion provided the highest mean score (60%; 95% CI, 55.0 to 65.0). Three factors were extracted that explain 70.8% of the variance: motivation (47.6% of variance, α = 0.86), capability (13.3% of variance, α = 0.83), and opportunity (10.0% of variance, α = 0.71). This study demonstrated a theoretically informed approach to identifying possible implementation difficulties in TUPAC counselling among dental providers. This approach provides a method for moving from diagnosing implementation difficulties to designing and evaluating interventions.
NASA Astrophysics Data System (ADS)
Xu, Kunshan; Qiu, Xingqi; Tian, Xiaoshuai
2018-01-01
The metal magnetic memory testing (MMMT) technique has been extensively applied in various fields because of its unique advantages of easy operation, low cost and high efficiency. However, very limited theoretical research has been conducted on application of MMMT to buried defects. To promote study in this area, the equivalent magnetic charge method is employed to establish a self-magnetic flux leakage (SMFL) model of a buried defect. Theoretical results based on the established model successfully capture basic characteristics of the SMFL signals of buried defects, as confirmed via experiment. In particular, the newly developed model can calculate the buried depth of a defect based on the SMFL signals obtained via testing. The results show that the new model can successfully assess the characteristics of buried defects, which is valuable in the application of MMMT in non-destructive testing.
NASA Astrophysics Data System (ADS)
Yang, Run-Qiu; Niu, Chao; Zhang, Cheng-Yong; Kim, Keun-Young
2018-02-01
We compute the time-dependent complexity of the thermofield double states by four different proposals: two holographic proposals based on the "complexity-action" (CA) conjecture and "complexity-volume" (CV) conjecture, and two quantum field theoretic proposals based on the Fubini-Study metric (FS) and Finsler geometry (FG). We find that four different proposals yield both similarities and differences, which will be useful to deepen our understanding on the complexity and sharpen its definition. In particular, at early time the complexity linearly increase in the CV and FG proposals, linearly decreases in the FS proposal, and does not change in the CA proposal. In the late time limit, the CA, CV and FG proposals all show that the growth rate is 2 E/(πℏ) saturating the Lloyd's bound, while the FS proposal shows the growth rate is zero. It seems that the holographic CV conjecture and the field theoretic FG method are more correlated.
NASA Astrophysics Data System (ADS)
Yalçın, Ergin; Alkış, Meltem; Seferoğlu, Nurgül; Seferoğlu, Zeynel
2018-03-01
A novel fluorescence coumarin-pyrazole-triazine based chemosensor (CPT) bearing 5-hydroxypyrazole as a receptoric part was synthesized and characterized by using IR, 1H/13C NMR and HRMS for the purpose of recognition of anions in DMSO. The most stable tautomeric form of CPT was determined by experimental techniques and theoretical calculations. The selectivity and sensitivity of CPT towards anions (CN-, F-, Cl-, Br-, I-, AcO-, HSO4-, H2PO4- and ClO4-) were determined using spectrophotometric and 1H NMR titration techniques as the experimental approach, and the results were explained by employing theoretical calculations. It was found to be suitable for the selective detection of F- in the presence of CN- and AcO- as competing anions. In addition, CPT exhibits significant "light-up" effect after interaction with TFA in CH2Cl2.
Delay-feedback control strategy for reducing CO2 emission of traffic flow system
NASA Astrophysics Data System (ADS)
Zhang, Li-Dong; Zhu, Wen-Xing
2015-06-01
To study the signal control strategy for reducing traffic emission theoretically, we first presented a kind of discrete traffic flow model with relative speed term based on traditional coupled map car-following model. In the model, the relative speed difference between two successive running cars is incorporated into following vehicle's acceleration running equation. Then we analyzed its stability condition with discrete control system stability theory. Third, we designed a delay-feedback controller to suppress traffic jam and decrease traffic emission based on modern controller theory. Last, numerical simulations are made to support our theoretical results, including the comparison of models' stability analysis, the influence of model type and signal control on CO2 emissions. The results show that the temporal behavior of our model is superior to other models, and the traffic signal controller has good effect on traffic jam suppression and traffic CO2 emission, which fully supports the theoretical conclusions.
Standards and Mastery Learning: Aligning Teaching and Assessment So All Children Can Learn.
ERIC Educational Resources Information Center
Gentile, J. Ronald; Lalley, James P.
This book describes the concept of mastery learning in the classroom and the various foundations upon which it is built. Five chapters discuss: (1) "Understanding Mastery Learning" (e.g., the learning/memory base, the measurement base, theoretical bases, and the brain base); (2) "Examining the Standards: Math, Science, Social Studies, and English…
Evidence-Based Administration for Decision Making in the Framework of Knowledge Strategic Management
ERIC Educational Resources Information Center
Del Junco, Julio Garcia; Zaballa, Rafael De Reyna; de Perea, Juan Garcia Alvarez
2010-01-01
Purpose: This paper seeks to present a model based on evidence-based administration (EBA), which aims to facilitate the creation, transformation and diffusion of knowledge in learning organizations. Design/methodology/approach: A theoretical framework is proposed based on EBA and the case method. Accordingly, an empirical study was carried out in…
Two-wavelength ghost imaging through atmospheric turbulence.
Shi, Dongfeng; Fan, Chengyu; Zhang, Pengfei; Shen, Hong; Zhang, Jinghui; Qiao, Chunhong; Wang, Yingjian
2013-01-28
Recent work has indicated that ghost imaging might find useful application in standoff sensing where atmospheric turbulence is a serious problem. There has been theoretical study of ghost imaging in the presence of turbulence. However, most work has addressed signal-wavelength ghost imaging. Two-wavelength ghost imaging through atmospheric turbulence is theoretically studied in this paper. Based on the extended Huygens-Fresnel integral, the analytical expressions describing atmospheric turbulence effects on the point spread function (PSF) and field of view (FOV) are derived. The computational case is also reported.
Mechanistic insights into the rhenium-catalyzed alcohol-to-olefin dehydration reaction.
Korstanje, Ties J; Jastrzebski, Johann T B H; Klein Gebbink, Robertus J M
2013-09-23
Rhenium-based complexes are powerful catalysts for the dehydration of various alcohols to the corresponding olefins. Here, we report on both experimental and theoretical (DFT) studies into the mechanism of the rhenium-catalyzed dehydration of alcohols to olefins in general, and the methyltrioxorhenium-catalyzed dehydration of 1-phenylethanol to styrene in particular. The experimental and theoretical studies are in good agreement, both showing the involvement of several proton transfers, and of a carbenium ion intermediate in the catalytic cycle. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Software reliability through fault-avoidance and fault-tolerance
NASA Technical Reports Server (NTRS)
Vouk, Mladen A.; Mcallister, David F.
1993-01-01
Strategies and tools for the testing, risk assessment and risk control of dependable software-based systems were developed. Part of this project consists of studies to enable the transfer of technology to industry, for example the risk management techniques for safety-concious systems. Theoretical investigations of Boolean and Relational Operator (BRO) testing strategy were conducted for condition-based testing. The Basic Graph Generation and Analysis tool (BGG) was extended to fully incorporate several variants of the BRO metric. Single- and multi-phase risk, coverage and time-based models are being developed to provide additional theoretical and empirical basis for estimation of the reliability and availability of large, highly dependable software. A model for software process and risk management was developed. The use of cause-effect graphing for software specification and validation was investigated. Lastly, advanced software fault-tolerance models were studied to provide alternatives and improvements in situations where simple software fault-tolerance strategies break down.
Anatomy of the Higgs fits: A first guide to statistical treatments of the theoretical uncertainties
NASA Astrophysics Data System (ADS)
Fichet, Sylvain; Moreau, Grégory
2016-04-01
The studies of the Higgs boson couplings based on the recent and upcoming LHC data open up a new window on physics beyond the Standard Model. In this paper, we propose a statistical guide to the consistent treatment of the theoretical uncertainties entering the Higgs rate fits. Both the Bayesian and frequentist approaches are systematically analysed in a unified formalism. We present analytical expressions for the marginal likelihoods, useful to implement simultaneously the experimental and theoretical uncertainties. We review the various origins of the theoretical errors (QCD, EFT, PDF, production mode contamination…). All these individual uncertainties are thoroughly combined with the help of moment-based considerations. The theoretical correlations among Higgs detection channels appear to affect the location and size of the best-fit regions in the space of Higgs couplings. We discuss the recurrent question of the shape of the prior distributions for the individual theoretical errors and find that a nearly Gaussian prior arises from the error combinations. We also develop the bias approach, which is an alternative to marginalisation providing more conservative results. The statistical framework to apply the bias principle is introduced and two realisations of the bias are proposed. Finally, depending on the statistical treatment, the Standard Model prediction for the Higgs signal strengths is found to lie within either the 68% or 95% confidence level region obtained from the latest analyses of the 7 and 8 TeV LHC datasets.
A Study on the Security Levels of Spread-Spectrum Embedding Schemes in the WOA Framework.
Wang, Yuan-Gen; Zhu, Guopu; Kwong, Sam; Shi, Yun-Qing
2017-08-23
Security analysis is a very important issue for digital watermarking. Several years ago, according to Kerckhoffs' principle, the famous four security levels, namely insecurity, key security, subspace security, and stego-security, were defined for spread-spectrum (SS) embedding schemes in the framework of watermarked-only attack. However, up to now there has been little application of the definition of these security levels to the theoretical analysis of the security of SS embedding schemes, due to the difficulty of the theoretical analysis. In this paper, based on the security definition, we present a theoretical analysis to evaluate the security levels of five typical SS embedding schemes, which are the classical SS, the improved SS (ISS), the circular extension of ISS, the nonrobust and robust natural watermarking, respectively. The theoretical analysis of these typical SS schemes are successfully performed by taking advantage of the convolution of probability distributions to derive the probabilistic models of watermarked signals. Moreover, simulations are conducted to illustrate and validate our theoretical analysis. We believe that the theoretical and practical analysis presented in this paper can bridge the gap between the definition of the four security levels and its application to the theoretical analysis of SS embedding schemes.
Developing Pedagogical Practices for English-Language Learners: A Design-Based Approach
ERIC Educational Resources Information Center
Iddings, Ana Christina DaSilva; Rose, Brian Christopher
2012-01-01
This study draws on the application of sociocultural theory to second-language learning and teaching to examine the impact of a design-based research approach on teacher development and literacy instruction to English-language learners (ELLs). Design-based research methodology was employed to derive theoretical suppositions relating to the process…
Using the 4MAT Framework to Design a Problem-Based Learning Biostatistics Course
ERIC Educational Resources Information Center
Nowacki, Amy S.
2011-01-01
The study presents and applies the 4MAT theoretical framework to educational planning to transform a biostatistics course into a problem-based learning experience. Using a four-question approach, described are specific activities/materials utilized at both the class and course levels. Two web-based instruments collected data regarding student…
GaSbBi/GaSb quantum-well and wire laser diodes
NASA Astrophysics Data System (ADS)
Ridene, Said
2018-06-01
In this work, we present detailed theoretical studies of the optical gain spectra and the emission wavelength of GaSb1-xBix/GaSb and traditional GaAs1-xBix/GaAs dilute-bismide quantum wells and wires (QWs, QWRs) focusing on comparison between their performances. It is found that the optical gain and the emission wavelength of the GaSb-based QW and QWRs lasers would be considerably greater than that of the GaAs-based QW lasers and QWRs for the same QW-, QWR-width, Bi-content and carrier density. The theoretical results were found to be in good agreement with available experimental data, especially for the emission wavelength given by GaSb-based QW laser diodes.
NASA Astrophysics Data System (ADS)
Zhu, Yawen; Cui, Xiaohong; Wang, Qianqian; Tong, Qiujie; Cui, Xutai; Li, Chenyu; Zhang, Le; Peng, Zhong
2016-11-01
The hardware-in-the-loop simulation system, which provides a precise, controllable and repeatable test conditions, is an important part of the development of the semi-active laser (SAL) guided weapons. In this paper, laser energy chain characteristics were studied, which provides a theoretical foundation for the SAL guidance technology and the hardware-in-the-loop simulation system. Firstly, a simplified equation was proposed to adjust the radar equation according to the principles of the hardware-in-the-loop simulation system. Secondly, a theoretical model and calculation method were given about the energy chain characteristics based on the hardware-in-the-loop simulation system. We then studied the reflection characteristics of target and the distance between the missile and target with major factors such as the weather factors. Finally, the accuracy of modeling was verified by experiment as the values measured experimentally generally follow the theoretical results from the model. And experimental results revealed that ratio of attenuation of the laser energy exhibited a non-linear change vs. pulse number, which were in accord with the actual condition.
NASA Astrophysics Data System (ADS)
Demirtaş, Güneş; Dege, Necmi; Ağar, Erbil; Uzun, Sümeyye Gümüş
2018-01-01
Two new salicylideneaniline (SA) derivative compounds (E)-2-(((4-chlorophenyl)imino)methyl)-5-(diethylamino)phenol, compound (I), and (E)-2-(((3-chlorophenyl)imino)methyl)-5-(diethylamino)phenol, compound (II), have been synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy, 1H NMR, 13C NMR and theoretical methods. Both of the compounds which are Schiff base derivatives are isomer of each other. While the compound (I) crystallizes in centrosymmetric monoclinic space group P 21/c, the compound (II) crystallizes in orthorhombic space group P 212121. The theoretical parameters of the molecules have been calculated by using Hartree-Fock (HF) and density functional theory (DFT/B3LYP) with 6-31G (d,p) basis set. These theoretical parameters have been compared with the experimental parameters obtained by XRD. The experimental geometries of the compounds have been superimposed with the theoretical geometries calculated by HF and DFT methods. Furthermore, the theoretical IR calculations, molecular electrostatic potential maps (MEP) and frontier molecular orbitals have been created for the compounds.
2012-01-01
Background An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework. Methods Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis. Results There was good support for a refinement of the framework comprising 14 domains of theoretical constructs (average silhouette value 0.29): ‘Knowledge’, ‘Skills’, ‘Social/Professional Role and Identity’, ‘Beliefs about Capabilities’, ‘Optimism’, ‘Beliefs about Consequences’, ‘Reinforcement’, ‘Intentions’, ‘Goals’, ‘Memory, Attention and Decision Processes’, ‘Environmental Context and Resources’, ‘Social Influences’, ‘Emotions’, and ‘Behavioural Regulation’. Conclusions The refined Theoretical Domains Framework has a strengthened empirical base and provides a method for theoretically assessing implementation problems, as well as professional and other health-related behaviours as a basis for intervention development. PMID:22530986
Professional Development for Design-Based Learning in Engineering Education: A Case Study
ERIC Educational Resources Information Center
Gómez Puente, Sonia M.; van Eijck, Michiel; Jochems, Wim
2015-01-01
Design-based learning (DBL) is an educational approach in which students gather and apply theoretical knowledge to solve design problems. In this study, we examined how critical DBL dimensions (project characteristics, design elements, the teacher's role, assessment, and social context) are applied by teachers in the redesign of DBL projects.…
ERIC Educational Resources Information Center
Simmie, Geraldine Mooney; de Paor, Cathal; Liston, Jennifer; O'Shea, John
2017-01-01
This study reports on findings from a critical literature review, from 2004 to 2014, in relation to the positioning of beginning teachers' professional learning during induction. The study uses theoretical frameworks drawn from competing discourses: an instrumental standpoint based on performativity and a dialectical standpoint based on a…
ERIC Educational Resources Information Center
Cunningham, Debra Jayne
2015-01-01
Using a constructivist grounded theory approach (Charmaz, 2006), this qualitative study examined how eight female senior-level professionals employed at faith-based colleges and universities processed and navigated the experience of involuntary job loss and successfully transitioned to another position. The theoretical framework of psychological…
Description of alpha-nucleus interaction cross sections for cosmic ray shielding studies
NASA Technical Reports Server (NTRS)
Cucinotta, Francis A.; Townsend, Lawrence W.; Wilson, John W.
1993-01-01
Nuclear interactions of high-energy alpha particles with target nuclei important for cosmic ray studies are discussed. Models for elastic, quasi-elastic, and breakup reactions are presented and compared with experimental data. Energy-dependent interaction cross sections and secondary spectra are presented based on theoretical models and the limited experimental data base.
ERIC Educational Resources Information Center
Ong, Chiek Pin; Tasir, Zaidatun
2015-01-01
The aim of the research is to study the information retention among trainee teachers using a self-instructional printed module based on Cognitive Load Theory for learning spreadsheet software. Effective pedagogical considerations integrating the theoretical concepts related to cognitive load are reflected in the design and development of the…
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…
Developing a theoretical framework for complex community-based interventions.
Angeles, Ricardo N; Dolovich, Lisa; Kaczorowski, Janusz; Thabane, Lehana
2014-01-01
Applying existing theories to research, in the form of a theoretical framework, is necessary to advance knowledge from what is already known toward the next steps to be taken. This article proposes a guide on how to develop a theoretical framework for complex community-based interventions using the Cardiovascular Health Awareness Program as an example. Developing a theoretical framework starts with identifying the intervention's essential elements. Subsequent steps include the following: (a) identifying and defining the different variables (independent, dependent, mediating/intervening, moderating, and control); (b) postulating mechanisms how the independent variables will lead to the dependent variables; (c) identifying existing theoretical models supporting the theoretical framework under development; (d) scripting the theoretical framework into a figure or sets of statements as a series of hypotheses, if/then logic statements, or a visual model; (e) content and face validation of the theoretical framework; and (f) revising the theoretical framework. In our example, we combined the "diffusion of innovation theory" and the "health belief model" to develop our framework. Using the Cardiovascular Health Awareness Program as the model, we demonstrated a stepwise process of developing a theoretical framework. The challenges encountered are described, and an overview of the strategies employed to overcome these challenges is presented.
Guo, Yujie; Shen, Jie; Ye, Xuchun; Chen, Huali; Jiang, Anli
2013-08-01
This paper aims to report the design and test the effectiveness of an innovative caring teaching model based on the theoretical framework of caring in the Chinese context. Since the 1970's, caring has been a core value in nursing education. In a previous study, a theoretical framework of caring in the Chinese context is explored employing a grounded theory study, considered beneficial for caring education. A caring teaching model was designed theoretically and a one group pre- and post-test quasi-experimental study was administered to test its effectiveness. From Oct, 2009 to Jul, 2010, a cohort of grade-2 undergraduate nursing students (n=64) in a Chinese medical school was recruited to participate in the study. Data were gathered through quantitative and qualitative methods to evaluate the effectiveness of the caring teaching model. The caring teaching model created an esthetic situation and experiential learning style for teaching caring that was integrated within the curricula. Quantitative data from the quasi-experimental study showed that the post-test scores of each item were higher than those on the pre-test (p<0.01). Thematic analysis of 1220 narratives from students' caring journals and reports of participant class observation revealed two main thematic categories, which reflected, from the students' points of view, the development of student caring character and the impact that the caring teaching model had on this regard. The model could be used as an integrated approach to teach caring in nursing curricula. It would also be beneficial for nursing administrators in cultivating caring nurse practitioners. Copyright © 2012 Elsevier Ltd. All rights reserved.
Topological Defects in Liquid Crystals: Studying the Correlation between Defects and Curvature
NASA Astrophysics Data System (ADS)
Melton, Charles
2015-03-01
Topological defects have recently been the subject of many fascinating studies in soft condensed matter physics. In particular, linking the evolution of topological defects to curvature changes has been a focus, leading possible applications in the areas such as cosmetics, pharmaceuticals, and electronics. In this study, defects in nematic liquid crystal droplets are investigated via laboratory and theoretical techniques. Nematic liquid crystal defects are reproduced via Monte Carlo simulations using a modified 2D XY-Model Hamiltonian. The simulation is performed on a curved surface to replicate a nematic droplet and examine possible defect configurations. To complement this theoretical work, we have trapped nematic droplets inside a dual-beam optical trap. This system allows controllable non-contact droplet deformation on a microscope based platform. Future work will focus on using the trap to stretch nematic droplets, correlating the changing topological defects with theoretical predictions.
Pyatak, Elizabeth A; Carandang, Kristine; Davis, Shain
2015-07-01
This article reports on the development of a manualized occupational therapy intervention for diabetes management. An initial theoretical framework and core content areas for a Stage I intervention manual were developed based on an in-depth needs assessment and review of existing literature. After evaluation by a panel of experts and completion of a feasibility study, the intervention was revised into a Stage 2 manual in preparation for a randomized study evaluating the intervention's efficacy. In developing the initial manual, we delineated core theoretical principles to allow for flexible application and tailoring of the intervention's content areas. Expert panel feedback and feasibility study results led to changes to the intervention structure and content as we developed the Stage 2 manual. Through describing this process, we illustrate the dynamic evolution of intervention manuals, which undergo revisions due to both theoretical and practical considerations at each stage of the research-to-clinical practice pipeline.
NASA Astrophysics Data System (ADS)
Chakraborty, Mitesh; Rai, Vineet Kumar
2017-12-01
The aim of the present paper is to employ theoretical methods to investigate the zero field splitting (ZFS) parameter and to investigate the position of the dopant in the host. These theoretical calculations have been compared with the empirical results. The superposition model (SPM) with the microscopic spin-Hamiltonian (MSH) theory and the coefficient of fractional parentage have been employed to investigate the dopant manganese(II) ion substitution in the diaquamalonatozinc(II) (DAMZ) single crystal. The magnetic parameters, viz. g-tensor and D-tensor, has been determined by using the ORCA program package developed by F Neese et al. The unrestricted Kohn-Sham orbitals-based Pederson-Khanna (PK) as the unperturbed wave function is observed to be the most suitable for the computational calculation of spin-orbit tensor (D^{SO}) of the axial ZFS parameter D. The effects of spin-spin dipolar couplings are taken into account. The unrestricted natural orbital (UNO) is used for the calculation of spin-spin dipolar contributions to the ZFS tensor. A comparative study of the quantum mechanical treatment of Pederson-Khanna (PK) with coupled perturbation (CP) is reported in the present study. The unrestricted Kohn-Sham-based natural orbital with Pederson-Khanna-type of perturbation approach validates the experimental results in the evaluation of ZFS parameters. The theoretical results are appropriate with the experimental ones and indicate the interstitial occupancy of Mn^{2+} ion in the host matrix.
Cao, Hui; Melton, Genevieve B.; Markatou, Marianthi; Hripcsak, George
2008-01-01
Inter-case similarity metrics can potentially help find similar cases from a case base for evidence-based practice. While several methods to measure similarity between cases have been proposed, developing an effective means for measuring patient case similarity remains a challenging problem. We were interested in examining how abstracting could potentially assist computing case similarity. In this study, abstracted patient-specific features from medical records were used to improve an existing information-theoretic measurement. The developed metric, using a combination of abstracted disease, finding, procedure and medication features, achieved a correlation between 0.6012 and 0.6940 to experts. PMID:18487093
Design and optimization of liquid core optical ring resonator for refractive index sensing.
Lin, Nai; Jiang, Lan; Wang, Sumei; Xiao, Hai; Lu, Yongfeng; Tsai, Hai-Lung
2011-07-10
This study performs a detailed theoretical analysis of refractive index (RI) sensors based on whispering gallery modes (WGMs) in liquid core optical ring resonators (LCORRs). Both TE- and TM-polarized WGMs of various orders are considered. The analysis shows that WGMs of higher orders need thicker walls to achieve a near-zero thermal drift, but WGMs of different orders exhibit a similar RI sensing performance at the thermostable wall thicknesses. The RI detection limit is very low at the thermostable thickness. The theoretical predications should provide a general guidance in the development of LCORR-based thermostable RI sensors. © 2011 Optical Society of America
Most theoretical and empirical studies of productivity–species richness relationships fail to consider linkages among trophic levels. We quantified productivity–richness relationships in detritus-based, water-filled tree-hole communities for two trophic levels: invertebrate consu...
Francis, Jill J; O'Connor, Denise; Curran, Janet
2012-04-24
Behaviour change is key to increasing the uptake of evidence into healthcare practice. Designing behaviour-change interventions first requires problem analysis, ideally informed by theory. Yet the large number of partly overlapping theories of behaviour makes it difficult to select the most appropriate theory. The need for an overarching theoretical framework of behaviour change was addressed in research in which 128 explanatory constructs from 33 theories of behaviour were identified and grouped. The resulting Theoretical Domains Framework (TDF) appears to be a helpful basis for investigating implementation problems. Research groups in several countries have conducted TDF-based studies. It seems timely to bring together the experience of these teams in a thematic series to demonstrate further applications and to report key developments. This overview article describes the TDF, provides a brief critique of the framework, and introduces this thematic series.In a brief review to assess the extent of TDF-based research, we identified 133 papers that cite the framework. Of these, 17 used the TDF as the basis for empirical studies to explore health professionals' behaviour. The identified papers provide evidence of the impact of the TDF on implementation research. Two major strengths of the framework are its theoretical coverage and its capacity to elicit beliefs that could signify key mediators of behaviour change. The TDF provides a useful conceptual basis for assessing implementation problems, designing interventions to enhance healthcare practice, and understanding behaviour-change processes. We discuss limitations and research challenges and introduce papers in this series.
2012-01-01
Behaviour change is key to increasing the uptake of evidence into healthcare practice. Designing behaviour-change interventions first requires problem analysis, ideally informed by theory. Yet the large number of partly overlapping theories of behaviour makes it difficult to select the most appropriate theory. The need for an overarching theoretical framework of behaviour change was addressed in research in which 128 explanatory constructs from 33 theories of behaviour were identified and grouped. The resulting Theoretical Domains Framework (TDF) appears to be a helpful basis for investigating implementation problems. Research groups in several countries have conducted TDF-based studies. It seems timely to bring together the experience of these teams in a thematic series to demonstrate further applications and to report key developments. This overview article describes the TDF, provides a brief critique of the framework, and introduces this thematic series. In a brief review to assess the extent of TDF-based research, we identified 133 papers that cite the framework. Of these, 17 used the TDF as the basis for empirical studies to explore health professionals’ behaviour. The identified papers provide evidence of the impact of the TDF on implementation research. Two major strengths of the framework are its theoretical coverage and its capacity to elicit beliefs that could signify key mediators of behaviour change. The TDF provides a useful conceptual basis for assessing implementation problems, designing interventions to enhance healthcare practice, and understanding behaviour-change processes. We discuss limitations and research challenges and introduce papers in this series. PMID:22531601
A molecular dynamics study of slow base flipping in DNA using conformational flooding.
Bouvier, Benjamin; Grubmüller, Helmut
2007-08-01
Individual DNA bases are known to be able to flip out of the helical stack, providing enzymes with access to the genetic information otherwise hidden inside the helix. Consequently, base flipping is a necessary first step to many more complex biological processes such as DNA transcription or replication. Much remains unknown about this elementary step, despite a wealth of experimental and theoretical studies. From the theoretical point of view, the involved timescale of milliseconds or longer requires the use of enhanced sampling techniques. In contrast to previous theoretical studies employing umbrella sampling along a predefined flipping coordinate, this study attempts to induce flipping without prior knowledge of the pathway, using information from a molecular dynamics simulation of a B-DNA fragment and the conformational flooding method. The relevance to base flipping of the principal components of the simulation is assayed, and a combination of modes optimally related to the flipping of the base through either helical groove is derived for each of the two bases of the central guanine-cytosine basepair. By applying an artificial flooding potential along these collective coordinates, the flipping mechanism is accelerated to within the scope of molecular dynamics simulations. The associated free energy surface is found to feature local minima corresponding to partially flipped states, particularly relevant to flipping in isolated DNA; further transitions from these minima to the fully flipped conformation are accelerated by additional flooding potentials. The associated free energy profiles feature similar barrier heights for both bases and pathways; the flipped state beyond is a broad and rugged attraction basin, only a few kcal/mol higher in energy than the closed conformation. This result diverges from previous works but echoes some aspects of recent experimental findings, justifying the need for novel approaches to this difficult problem: this contribution represents a first step in this direction. Important structural factors involved in flipping, both local (sugar-phosphate backbone dihedral angles) and global (helical axis bend), are also identified.
NASA Astrophysics Data System (ADS)
Gayathri, Kasirajan; Radhika, Ramachandran; Shankar, Ramasamy; Malathi, Mahalingam; Savithiri, Krishnaswamy; Sparkes, Hazel A.; Howard, Judith A. K.; Mohan, Palathurai Subramaniam
2017-04-01
A novel compound 2-chloro-3,6-bis-(quinolin-8-yloxymethyl)-quinoline 3 bearing a tri-quinoline moiety has been synthesized from 2-chloro-3,6-dimethyl quinoline 1 and 8-hydroxy quinoline 2 using dry acetone and K2CO3 as a base. 3 has been characterized by using FT-IR, FT-Raman, UV-Vis, 1H NMR, 13C NMR spectra and single crystal X-ray diffraction methods. We have also made a combined experimental and theoretical study on the molecular structure, vibrational spectra, NMR, FT-IR, FT-Raman and UV-Vis spectra of 2-chloro-3,6-bis-(quinolin-8-yloxymethyl)-quinoline. The theoretical studies of the title compound have been evaluated by using density functional theory calculations using B3LYP/6-31+G(d,p) and M06-2X/6-31+G(d,p) level of theories. The calculated theoretical values were found to be in good agreement with the experimental findings. The single crystal structure 3 crystallized in the orthorhombic space group Pna21. The compound 3 exhibits higher cytotoxicity in human cervical cancer cell lines (HeLa) than human breast cancer cell lines (MCF7).
Self-assembly in Dipolar Fluids
NASA Astrophysics Data System (ADS)
Ronti, Michela; Kantorovich, Sofia
We are studying low temperature structural transitions in dipolar hard spheres (DHS), combining grand-canonical Monte Carlo simulations and direct analytical theoretical calculations. DHS is characterized by long-range anisotropic interactions: it consists of a point dipole at the center of a hard sphere. We are interested in low temperature and low density phase behaviour of DHS systems. From a theoretical point of view the process of self-assembly is not responsible for a phase transition; this belief was completely reverted by theoretical studies showing that the process of self-assembly is alone capable to induce phase transition. On the other hand in the last years it was proved that no sign of critical behaviour is observed, implementing efficient and tailored Monte Carlo algorithms. Moreover a theoretical approach based on Density Functional Theory was developed: a series of structural transitions were discovered providing evidence of a hierarchy in the structures on cooling. We are performing free-energy calculations in order to draw the phase diagram of DHS model. Comparing the numerical results with the theoretical ones shed light on the scenario of temperature induced structural transitions in magnetic nanocolloids. Etn-COLLDENSE (H2020-MCSA-ITN-2014, Grant No. 642774).
Trefz, F M; Lorch, A; Feist, M; Sauter-Louis, C; Lorenz, I
2012-01-01
Clinical assessment of metabolic acidosis in calves with neonatal diarrhea can be difficult because increased blood concentrations of d-lactate and not acidemia per se are responsible for most of the clinical signs exhibited by these animals. To describe the correlation between clinical and laboratory findings and d-lactate concentrations. Furthermore, the theoretical outcome of a simplified treatment protocol based on posture/ability to stand and degree of dehydration was evaluated. A total of 121 calves with diagnosis of neonatal diarrhea admitted to a veterinary teaching hospital during an 8-month study period. Prospective blinded cohort study. Physical examinations were carried out following a standardized protocol. Theoretical outcome of treatment was calculated. Type and degree of metabolic acidosis were age dependent. The clinical parameters posture, behavior, and palpebral reflex were closely correlated to base excess (r = 0.74, 0.78, 0.68; P < .001) and d-lactate concentrations (r = 0.59, 0.59, 0.71; P < .001), respectively. Thus, determining the degree of loss of the palpebral reflex was identified as the best clinical tool for diagnosing increase in serum d-lactate concentrations. Theoretical outcome of treatment revealed that the tested dosages of sodium bicarbonate are more likely to overdose than to underdose calves with diarrhea and metabolic acidosis. The degree of metabolic acidosis in diarrheic calves can be predicted based on clinical findings. The assessed protocol provides a useful tool to determine bicarbonate requirements, but a revision is necessary for calves with ability to stand and marked metabolic acidosis. Copyright © 2011 by the American College of Veterinary Internal Medicine.
An, Ni; Zhuang, Bilin; Li, Minglun; Lu, Yuyuan; Wang, Zhen-Gang
2015-08-20
We propose a simple theoretical formula for describing the refractive indices in binary liquid mixtures containing salt ions. Our theory is based on the Clausius-Mossotti equation; it gives the refractive index of the mixture in terms of the refractive indices of the pure liquids and the polarizability of the ionic species, by properly accounting for the volume change upon mixing. The theoretical predictions are tested by extensive experimental measurements of the refractive indices for water-acetonitrile-salt systems for several liquid compositions, different salt species, and a range of salt concentrations. Excellent agreement is obtained in all cases, especially at low salt concentrations, with no fitting parameters. A simplified expression of the refractive index for low salt concentration is also given, which can be the theoretical basis for determination of salt concentration using refractive index measurements.
Theoretical study in carrier mobility of two-dimensional materials
NASA Astrophysics Data System (ADS)
Huang, R.
2017-09-01
Recently, the theoretical prediction on carrier mobility of two-dimensional (2D) materials has aroused wild attention. At present, there is still a large gap between the theoretical prediction and the device performance of the semiconductor based on the 2D layer semiconductor materials such as graphene. It is particularly important to theoretically design and screen the high-performance 2D layered semiconductor materials with suitable band gap and high carrier mobility. This paper introduces some 2D materials with fine properties and deduces the formula for mobility of the isotropic materials on the basis of the deformation potential theory and Fermic golden rule under acoustic phonon scattering conditions, and then discusses the carrier mobility of anisotropic materials with Dirac cones. We point out the misconceptions in the existing literature and discuss the correct ones.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Galperin, Michael
The progress of experimental techniques at the nanoscale in the last decade made optical measurements in current-carrying nanojunctions a reality, thus indicating the emergence of a new field of research coined optoelectronics. Optical spectroscopy of open nonequilibrium systems is a natural meeting point for (at least) two research areas: nonlinear optical spectroscopy and quantum transport, each with its own theoretical toolbox. We review recent progress in the field comparing theoretical treatments of optical response in nanojunctions as is accepted in nonlinear spectroscopy and quantum transport communities. A unified theoretical description of spectroscopy in nanojunctions is presented. Here, we argue thatmore » theoretical approaches of the quantum transport community (and in particular, the Green function based considerations) yield a convenient tool for optoelectronics when the radiation field is treated classically, and that differences between the toolboxes may become critical when studying the quantum radiation field in junctions.« less
Game-Based Learning in Science Education: A Review of Relevant Research
NASA Astrophysics Data System (ADS)
Li, Ming-Chaun; Tsai, Chin-Chung
2013-12-01
The purpose of this study is to review empirical research articles regarding game-based science learning (GBSL) published from 2000 to 2011. Thirty-one articles were identified through the Web of Science and SCOPUS databases. A qualitative content analysis technique was adopted to analyze the research purposes and designs, game design and implementation, theoretical backgrounds and learning foci of these reviewed studies. The theories and models employed by these studies were classified into four theoretical foundations including cognitivism, constructivism, the socio-cultural perspective, and enactivism. The results indicate that cognitivism and constructivism were the major theoretical foundations employed by the GBSL researchers and that the socio-cultural perspective and enactivism are two emerging theoretical paradigms that have started to draw attention from GBSL researchers in recent years. The analysis of the learning foci showed that most of the digital games were utilized to promote scientific knowledge/concept learning, while less than one-third were implemented to facilitate the students' problem-solving skills. Only a few studies explored the GBSL outcomes from the aspects of scientific processes, affect, engagement, and socio-contextual learning. Suggestions are made to extend the current GBSL research to address the affective and socio-contextual aspects of science learning. The roles of digital games as tutor, tool, and tutee for science education are discussed, while the potentials of digital games to bridge science learning between real and virtual worlds, to promote collaborative problem-solving, to provide affective learning environments, and to facilitate science learning for younger students are also addressed.
Cane, James; Richardson, Michelle; Johnston, Marie; Ladha, Ruhina; Michie, Susan
2015-02-01
Behaviour change technique (BCT) Taxonomy v1 is a hierarchically grouped, consensus-based taxonomy of 93 BCTs for reporting intervention content. To enhance the use and understanding of BCTs, the aims of the present study were to (1) quantitatively examine the 'bottom-up' hierarchical structure of Taxonomy v1, (2) identify whether BCTs can be reliably mapped to theoretical domains using a 'top-down' theoretically driven approach, and (3) identify any overlap between the 'bottom-up' and 'top-down' groupings. The 'bottom-up' structure was examined for higher-order groupings using a dendrogram derived from hierarchical cluster analysis. For the theory-based 'top-down' structure, 18 experts sorted BCTs into 14 theoretical domains. Discriminant Content Validity was used to identify groupings, and chi-square tests and Pearson's residuals were used to examine the overlap between groupings. Behaviour change techniques relating to 'Reward and Punishment' and 'Cues and Cue Responses' were perceived as markedly different to other BCTs. Fifty-nine of the BCTs were reliably allocated to 12 of the 14 theoretical domains; 47 were significant and 12 were of borderline significance. Thirty-four of 208 'bottom-up' × 'top-down' pairings showed greater overlap than expected by chance. However, only six combinations achieved satisfactory evidence of similarity. The moderate overlap between the groupings indicates some tendency to implicitly conceptualize BCTs in terms of the same theoretical domains. Understanding the nature of the overlap will aid the conceptualization of BCTs in terms of theory and application. Further research into different methods of developing a hierarchical taxonomic structure of BCTs for international, interdisciplinary work is now required. Statement of contribution What is already known on this subject? Behaviour change interventions are effective in improving health care and health outcomes. The 'active' components of these interventions are behaviour change techniques and over 93 have been identified. Taxonomies of behaviour change techniques require structure to enable potential applications. What does this study add? This study identifies groups of BCTs to aid the recall of BCTs for intervention coding and design. It compares two methods of grouping--'bottom-up' and theory-based 'top-down'--and finds a moderate overlap. Building on identified BCT groups, it examines relationships between theoretical domains and BCTs. © 2014 The British Psychological Society.
Allen, Kyle R; Hazelett, Susan E; Radwany, Steven; Ertle, Denise; Fosnight, Susan M; Moore, Pamela S
2012-04-01
Practice guidelines are available for hospice and palliative medicine specialists and geriatricians. However, these guidelines do not adequately address the needs of patients who straddle the 2 specialties: homebound chronically ill patients. The purpose of this article is to describe the theoretical basis for the Promoting Effective Advance Care for Elders (PEACE) randomized pilot study. PEACE is an ongoing 2-group randomized pilot study (n=80) to test an in-home interdisciplinary care management intervention that combines palliative care approaches to symptom management, psychosocial and emotional support, and advance care planning with geriatric medicine approaches to optimizing function and addressing polypharmacy. The population comprises new enrollees into PASSPORT, Ohio's community-based, long-term care Medicaid waiver program. All PASSPORT enrollees have geriatric/palliative care crossover needs because they are nursing home eligible. The intervention is based on Wagner's Chronic Care Model and includes comprehensive interdisciplinary care management for these low-income frail elders with chronic illnesses, uses evidence-based protocols, emphasizes patient activation, and integrates with community-based long-term care and other community agencies. Our model, with its standardized, evidence-based medical and psychosocial intervention protocols, will transport easily to other sites that are interested in optimizing outcomes for community-based, chronically ill older adults. © Mary Ann Liebert, Inc.
Theoretical Perspectives Guiding QOL Indicator Projects
ERIC Educational Resources Information Center
Sirgy, M. Joseph
2011-01-01
Most of the theoretically based QOL indicators projects can be classified in terms of six major theoretical concepts: (a) socio-economic development (b) personal utility, (c) just society, (d) human development, (e) sustainability, and (f) functioning. I explain the core aspects of these six theoretical paradigms and show how they help guide QOL…
Towards improving the NASA standard soil moisture retrieval algorithm and product
NASA Astrophysics Data System (ADS)
Mladenova, I. E.; Jackson, T. J.; Njoku, E. G.; Bindlish, R.; Cosh, M. H.; Chan, S.
2013-12-01
Soil moisture mapping using passive-based microwave remote sensing techniques has proven to be one of the most effective ways of acquiring reliable global soil moisture information on a routine basis. An important step in this direction was made by the launch of the Advanced Microwave Scanning Radiometer on the NASA's Earth Observing System Aqua satellite (AMSR-E). Along with the standard NASA algorithm and operational AMSR-E product, the easy access and availability of the AMSR-E data promoted the development and distribution of alternative retrieval algorithms and products. Several evaluation studies have demonstrated issues with the standard NASA AMSR-E product such as dampened temporal response and limited range of the final retrievals and noted that the available global passive-based algorithms, even though based on the same electromagnetic principles, produce different results in terms of accuracy and temporal dynamics. Our goal is to identify the theoretical causes that determine the reduced sensitivity of the NASA AMSR-E product and outline ways to improve the operational NASA algorithm, if possible. Properly identifying the underlying reasons that cause the above mentioned features of the NASA AMSR-E product and differences between the alternative algorithms requires a careful examination of the theoretical basis of each approach. Specifically, the simplifying assumptions and parametrization approaches adopted by each algorithm to reduce the dimensionality of unknowns and characterize the observing system. Statistically-based error analyses, which are useful and necessary, provide information on the relative accuracy of each product but give very little information on the theoretical causes, knowledge that is essential for algorithm improvement. Thus, we are currently examining the possibility of improving the standard NASA AMSR-E global soil moisture product by conducting a thorough theoretically-based review of and inter-comparisons between several well established global retrieval techniques. A detailed discussion focused on the theoretical basis of each approach and algorithms sensitivity to assumptions and parametrization approaches will be presented. USDA is an equal opportunity provider and employer.
Couples coping with cancer: exploration of theoretical frameworks from dyadic studies.
Regan, Tim W; Lambert, Sylvie D; Kelly, Brian; Falconier, Mariana; Kissane, David; Levesque, Janelle V
2015-12-01
A diagnosis of cancer and subsequent treatment are distressing not only for the person directly affected, but also for their intimate partner. The aim of this review is to (a) identify the main theoretical frameworks underpinning research addressing dyadic coping among couples affected by cancer, (b) summarise the evidence supporting the concepts described in these theoretical frameworks, and (c) examine the similarities and differences between these theoretical perspectives. A literature search was undertaken to identify descriptive studies published between 1990 and 2013 (English and French) that examined the interdependence of patients' and partners' coping, and the impact of coping on psychosocial outcomes. Data were extracted using a standardised form and reviewed by three of the authors. Twenty-three peer-reviewed manuscripts were identified, from which seven theoretical perspectives were derived: Relationship-Focused Coping, Transactional Model of Stress and Coping, Systemic-Transactional Model (STM) of dyadic coping, Collaborative Coping, Relationship Intimacy model, Communication models, and Coping Congruence. Although these theoretical perspectives emphasised different aspects of coping, a number of conceptual commonalities were noted. This review identified key theoretical frameworks of dyadic coping used in cancer. Evidence indicates that responses within the couple that inhibit open communication between partner and patient are likely to have an adverse impact on psychosocial outcomes. Models that incorporate the interdependence of emotional responses and coping behaviours within couples have an emerging evidence base in psycho-oncology and may have greatest validity and clinical utility in this setting. Copyright © 2015 John Wiley & Sons, Ltd.
Video- or text-based e-learning when teaching clinical procedures? A randomized controlled trial.
Buch, Steen Vigh; Treschow, Frederik Philip; Svendsen, Jesper Brink; Worm, Bjarne Skjødt
2014-01-01
This study investigated the effectiveness of two different levels of e-learning when teaching clinical skills to medical students. Sixty medical students were included and randomized into two comparable groups. The groups were given either a video- or text/picture-based e-learning module and subsequently underwent both theoretical and practical examination. A follow-up test was performed 1 month later. The students in the video group performed better than the illustrated text-based group in the practical examination, both in the primary test (P<0.001) and in the follow-up test (P<0.01). Regarding theoretical knowledge, no differences were found between the groups on the primary test, though the video group performed better on the follow-up test (P=0.04). Video-based e-learning is superior to illustrated text-based e-learning when teaching certain practical clinical skills.
Video- or text-based e-learning when teaching clinical procedures? A randomized controlled trial
Buch, Steen Vigh; Treschow, Frederik Philip; Svendsen, Jesper Brink; Worm, Bjarne Skjødt
2014-01-01
Background and aims This study investigated the effectiveness of two different levels of e-learning when teaching clinical skills to medical students. Materials and methods Sixty medical students were included and randomized into two comparable groups. The groups were given either a video- or text/picture-based e-learning module and subsequently underwent both theoretical and practical examination. A follow-up test was performed 1 month later. Results The students in the video group performed better than the illustrated text-based group in the practical examination, both in the primary test (P<0.001) and in the follow-up test (P<0.01). Regarding theoretical knowledge, no differences were found between the groups on the primary test, though the video group performed better on the follow-up test (P=0.04). Conclusion Video-based e-learning is superior to illustrated text-based e-learning when teaching certain practical clinical skills. PMID:25152638
Design-Based Research: Case of a Teaching Sequence on Mechanics
ERIC Educational Resources Information Center
Tiberghien, Andree; Vince, Jacques; Gaidioz, Pierre
2009-01-01
Design-based research, and particularly its theoretical status, is a subject of debate in the science education community. In the first part of this paper, a theoretical framework drawn up to develop design-based research will be presented. This framework is mainly based on epistemological analysis of physics modelling, learning and teaching…
Theoretical model of gravitational perturbation of current collector axisymmetric flow field
NASA Astrophysics Data System (ADS)
Walker, John S.; Brown, Samuel H.; Sondergaard, Neal A.
1989-03-01
Some designs of liquid metal collectors in homopolar motors and generators are essentially rotating liquid metal fluids in cylindrical channels with free surfaces and will, at critical rotational speeds, become unstable. The role of gravity in modifying this ejection instability is investigated. Some gravitational effects can be theoretically treated by perturbation techniques on the axisymmetric base flow of the liquid metal. This leads to a modification of previously calculated critical current collector ejection values neglecting gravity effects. The derivation of the mathematical model which determines the perturbation of the liquid metal base flow due to gravitational effects is documented. Since gravity is a small force compared with the centrifugal effects, the base flow solutions can be expanded in inverse powers of the Froude number and modified liquid flow profiles can be determined as a function of the azimuthal angle. This model will be used in later work to theoretically study the effects of gravity on the ejection point of the current collector. A rederivation of the hydrodynamic instability threshold of a liquid metal current collector is presented.
Theoretical model of gravitational perturbation of current collector axisymmetric flow field
NASA Astrophysics Data System (ADS)
Walker, John S.; Brown, Samuel H.; Sondergaard, Neal A.
1990-05-01
Some designs of liquid-metal current collectors in homopolar motors and generators are essentially rotating liquid-metal fluids in cylindrical channels with free surfaces and will, at critical rotational speeds, become unstable. An investigation at David Taylor Research Center is being performed to understand the role of gravity in modifying this ejection instability. Some gravitational effects can be theoretically treated by perturbation techniques on the axisymmetric base flow of the liquid metal. This leads to a modification of previously calculated critical-current-collector ejection values neglecting gravity effects. The purpose of this paper is to document the derivation of the mathematical model which determines the perturbation of the liquid-metal base flow due to gravitational effects. Since gravity is a small force compared with the centrifugal effects, the base flow solutions can be expanded in inverse powers of the Froude number and modified liquid-flow profiles can be determined as a function of the azimuthal angle. This model will be used in later work to theoretically study the effects of gravity on the ejection point of the current collector.
Osiurak, François
2014-06-01
Our understanding of human tool use comes mainly from neuropsychology, particularly from patients with apraxia or action disorganization syndrome. However, there is no integrative, theoretical framework explaining what these neuropsychological syndromes tell us about the cognitive/neural bases of human tool use. The goal of the present article is to fill this gap, by providing a theoretical framework for the study of human tool use: The Four Constraints Theory (4CT). This theory rests on two basic assumptions. First, everyday tool use activities can be formalized as multiple problem situations consisted of four distinct constraints (mechanics, space, time, and effort). Second, each of these constraints can be solved by the means of a specific process (technical reasoning, semantic reasoning, working memory, and simulation-based decision-making, respectively). Besides presenting neuropsychological evidence for 4CT, this article shall address epistemological, theoretical and methodological issues I will attempt to resolve. This article will discuss how 4CT diverges from current cognitive models about several widespread hypotheses (e.g., notion of routine, direct and automatic activation of tool knowledge, simulation-based tool knowledge).
Bhuiya, Sutanwi; Haque, Lucy; Goswami, Rapti; Das, Suman
2017-12-14
The interactions of RNA triplex (U.A*U) and duplex (A.U) with naturally occurring flavonoid fisetin (FTN) have been examined at pH 7.0 using various spectroscopic, viscometric, and theoretical studies. Experimental observations showed that the ligand binds with both double- and triple-helical forms of RNA, although the binding affinity is greater for the triplex structure (5.94 × 10 6 M -1 ) compared to that for the duplex counterpart (1.0 × 10 5 M -1 ). Thermal melting experiments revealed that the Hoogsteen base-paired third strand of triplex was stabilized to a greater extent (∼14 °C) compared with the Watson-Crick base-paired second strand (∼4 °C) in the presence of FTN. From fluorimetric study, we observed that U.A*U and A.U primarily bind to the photoproduced tautomer of FTN in the excited state. Steady-state and time-resolved anisotropy measurements illustrate considerable modulations of the spectroscopic properties of the tautomeric FTN within the RNA environment. Viscometric, fluorescence quenching, and thermal melting studies all together support the mode of binding to be intercalation. Theoretical study explains the experimental absorption and emission (dual fluorescence) behavior of FTN along with the excited-state intramolecular proton transfer process.
Professional development for design-based learning in engineering education: a case study
NASA Astrophysics Data System (ADS)
Gómez Puente, Sonia M.; van Eijck, Michiel; Jochems, Wim
2015-01-01
Design-based learning (DBL) is an educational approach in which students gather and apply theoretical knowledge to solve design problems. In this study, we examined how critical DBL dimensions (project characteristics, design elements, the teacher's role, assessment, and social context) are applied by teachers in the redesign of DBL projects. We conducted an intervention for the professional development of the DBL teachers in the Mechanical Engineering and the Electrical Engineering departments. We used the Experiential Learning Cycle as an educational model for the professionalisation programme. The findings show that the programme encouraged teachers to apply the DBL theoretical framework. However, there are some limitations with regard to specific project characteristics. Further research into supporting teachers to develop open-ended and multidisciplinary activities in the projects that support learning is recommended.
2006-04-17
of the droplet phase are then used for validation of theoretical models of the gas-droplet plume flow. Based on experimental and numerical results...with the continuous model adequately reproduces the Arrhenius rate at high temperatures but significantly underpredicts the theoretical rate at low...continuous model and discrete model of real gas effects, and the results on the shock -wave stand-off distance were compared with the experimental data of
NASA Astrophysics Data System (ADS)
Tasolamprou, A. C.; Mitov, M.; Zografopoulos, D. C.; Kriezis, E. E.
2009-03-01
Single-layer cholesteric liquid crystals exhibit a reflection coefficient which is at most 50% for unpolarized incident light. We give theoretical and experimental evidence of single-layer polymer-stabilized cholesteric liquid-crystalline structures that demonstrate hyper-reflective properties. Such original features are derived by the concurrent and randomly interlaced presence of both helicities. The fundamental properties of such structures are revealed by detailed numerical simulations based on a stochastic approach.
Stability of Castering Wheels for Aircraft Landing Gears
NASA Technical Reports Server (NTRS)
Kantrowitz, Arthur
1940-01-01
A theoretical study was made of the shimmy of castering wheels. The theory is based on the discovery of a phenomenon called kinematic shimmy. Experimental checks, use being made of a model having low-pressure tires, are reported and the applicability of the results to full scale is discussed. Theoretical methods of estimating the spindle viscous damping and the spindle solid friction necessary to avoid shimmy are given. A new method of avoiding shimmy -- lateral freedom -- is introduced.
Organizational strategy, structure, and process.
Miles, R E; Snow, C C; Meyer, A D; Coleman, H J
1978-07-01
Organizational adaptation is a topic that has received only limited and fragmented theoretical treatment. Any attempt to examine organizational adaptation is difficult, since the process is highly complex and changeable. The proposed theoretical framework deals with alternative ways in which organizations define their product-market domains (strategy) and construct mechanisms (structures and processes) to pursue these strategies. The framework is based on interpretation of existing literature and continuing studies in four industries (college textbook publishing, electronics, food processing, and health care).
Transforming the Curriculum: Ethnic Studies and Women's Studies.
ERIC Educational Resources Information Center
Butler, Johnnella E., Ed.; Walter, John C., Ed.
This book provides a collection of 19 essays that discuss curricular change in higher education regarding ethnic and women's studies, and presents the theoretical and practical bases for accomplishing this restyling. The papers and authors are as follows: "The Difficult Dialogue of Curriculum Transformation: Ethnic Studies and Women's Studies"…
Information-theoretic metamodel of organizational evolution
NASA Astrophysics Data System (ADS)
Sepulveda, Alfredo
2011-12-01
Social organizations are abstractly modeled by holarchies---self-similar connected networks---and intelligent complex adaptive multiagent systems---large networks of autonomous reasoning agents interacting via scaled processes. However, little is known of how information shapes evolution in such organizations, a gap that can lead to misleading analytics. The research problem addressed in this study was the ineffective manner in which classical model-predict-control methods used in business analytics attempt to define organization evolution. The purpose of the study was to construct an effective metamodel for organization evolution based on a proposed complex adaptive structure---the info-holarchy. Theoretical foundations of this study were holarchies, complex adaptive systems, evolutionary theory, and quantum mechanics, among other recently developed physical and information theories. Research questions addressed how information evolution patterns gleamed from the study's inductive metamodel more aptly explained volatility in organization. In this study, a hybrid grounded theory based on abstract inductive extensions of information theories was utilized as the research methodology. An overarching heuristic metamodel was framed from the theoretical analysis of the properties of these extension theories and applied to business, neural, and computational entities. This metamodel resulted in the synthesis of a metaphor for, and generalization of organization evolution, serving as the recommended and appropriate analytical tool to view business dynamics for future applications. This study may manifest positive social change through a fundamental understanding of complexity in business from general information theories, resulting in more effective management.
Optoelectronic Terminal-Attractor-Based Associative Memory
NASA Technical Reports Server (NTRS)
Liu, Hua-Kuang; Barhen, Jacob; Farhat, Nabil H.
1994-01-01
Report presents theoretical and experimental study of optically and electronically addressable optical implementation of artificial neural network that performs associative recall. Shows by computer simulation that terminal-attractor-based associative memory can have perfect convergence in associative retrieval and increased storage capacity. Spurious states reduced by exploiting terminal attractors.
Collaborative Communication in Work Based Learning Programs
ERIC Educational Resources Information Center
Wagner, Stephen Allen
2017-01-01
This basic qualitative study, using interviews and document analysis, examined reflections from a Work Based Learning (WBL) program to understand how utilizing digital collaborative communication tools influence the educational experience. The Community of Inquiry (CoI) framework was used as a theoretical frame promoting the examination of the…
Wolter, J
1999-01-01
Pavlovian conditioning in animals is often evaluated by means of transfer of control experiments. With human subjects, however, only very few studies have been conducted and the outcomes were often not in accordance with theoretical explanations based on studies with animals. A theoretical framework is presented that tries to integrate the results of the human conditioning paradigm and the animal conditioning paradigm as well, with reference to the well-known Yerkes-Dodson law. The experimental study with human subjects (N = 24) confirmed the predictions out of this framework, when a procedure similar to animal research is applied.
Compaction Behavior of Granular Materials
NASA Astrophysics Data System (ADS)
Endicott, Mark R.; Kenkre, V. M.; Glass, S. Jill; Hurd, Alan J.
1996-03-01
We report the results of our recent study of compaction of granular materials. A theoretical model is developed for the description of the compaction of granular materials exemplified by granulated ceramic powders. Its predictions are compared to observations of uniaxial compaction tests of ceramic granules of PMN-PT, spray dried alumina and rutile. The theoretical model employs a volume-based statistical mechanics treatment and an activation analogy. Results of a computer simulation of random packing of discs in two dimensions are also reported. The effect of type of particle size distribution and other parameters of that distribution on the calculated quantities are discussed. We examine the implications of the results of the simulation for the theoretical model.
NASA Astrophysics Data System (ADS)
Wang, Chao; Xiao, Jun; Luo, Xiaobing
2016-10-01
The neutron inelastic scattering cross section of 115In has been measured by the activation technique at neutron energies of 2.95, 3.94, and 5.24 MeV with the neutron capture cross sections of 197Au as an internal standard. The effects of multiple scattering and flux attenuation were corrected using the Monte Carlo code GEANT4. Based on the experimental values, the 115In neutron inelastic scattering cross sections data were theoretically calculated between the 1 and 15 MeV with the TALYS software code, the theoretical results of this study are in reasonable agreement with the available experimental results.
Structural characterisation of some vanillic Mannich bases: Experimental and theoretical study
NASA Astrophysics Data System (ADS)
Petrović, Vladimir P.; Simijonović, Dušica; Novaković, Sladjana B.; Bogdanović, Goran A.; Marković, Svetlana; Petrović, Zorica D.
2015-10-01
In this paper, synthesis and structural determination of 2-[1-(N-4-fluorophenylamino)-1-(4-hydroxy-3-methoxyphenyl)]methylcyclohexanone (MB-F) is presented. To determine the structure of this new compound, IR and NMR spectral characterisation was performed experimentally and theoretically. Simulation of spectral data was carried out using three functionals: B3LYP, B3LYP-D2, and M06-2X. The results obtained for MB-F were compared to those attained for similar, known compound 2-[1-(N-phenylamino)-1-(4-hydroxy-3-methoxyphenyl)]methylcyclohexanone (MB-H), whose crystal structure is presented here. Taking into account all experimental and theoretical findings, the structure of MB-F was proposed.
Theoretical tuning of the firefly bioluminescence spectra by the modification of oxyluciferin
NASA Astrophysics Data System (ADS)
Cheng, Yuan-Yuan; Zhu, Jia; Liu, Ya-Jun
2014-01-01
Extending the firefly bioluminescence is of practical significance for the improved visualization of living cells and the development of a multicolor reporter. Tuning the color of bioluminescence in fireflies mainly involves the modification of luciferase and luciferin. In this Letter, we theoretically studied the emission spectra of 9 firefly oxyluciferin analogs in the gas phase and in solutions. Three density functionals, including B3LYP, CAM-B3LYP and M06-2X, were employed to theoretically predict the efficiently luminescent analogs. The reliable functionals for calculating the targeted systems were suggested. The luminescence efficiency, solvent effects, and substituent effects are discussed based on the calculated results.
Acceptance- versus Change-Based Pain Management: The Role of Psychological Acceptance
ERIC Educational Resources Information Center
Blacker, Kara J.; Herbert, James D.; Forman, Evan M.; Kounios, John
2012-01-01
This study compared two theoretically opposed strategies for acute pain management: an acceptance-based and a change-based approach. These two strategies were compared in a within-subjects design using the cold pressor test as an acute pain induction method. Participants completed a baseline pain tolerance assessment followed by one of the two…
ERIC Educational Resources Information Center
Kuhn, Ida Kristina
2017-01-01
This study investigates the enhancement of social competence for disadvantaged young people based on the example of the "Werkschule Bremen" educational course. Theoretical approaches to social competence as a learning outcome are mainly based on the model of social information processing, although the meaning of both practical and…
A World Apart? Bridging the Gap between Theory and Applied Social Gerontology
ERIC Educational Resources Information Center
Hendricks, Jon; Applebaum, Robert; Kunkel, Suzanne
2010-01-01
This article is based on the premise that there is inadequate attention to the link between theory and applied research in social gerontology. The article contends that applied research studies do not often or effectively employ a theoretical framework and that theory-based articles, including theory-based research, are not often focused on…
ERIC Educational Resources Information Center
Sadler, Troy D.; Romine, William L.; Topçu, Mustafa Sami
2016-01-01
Science educators have presented numerous conceptual and theoretical arguments in favor of teaching science through the exploration of socio-scientific issues (SSI). However, the empirical knowledge base regarding the extent to which SSI-based instruction supports student learning of science content is limited both in terms of the number of…
ERIC Educational Resources Information Center
Sharma, Shreela; Chuang, Ru-Jye; Hedberg, Ann Marie
2011-01-01
Background: The literature on theoretically-based programs targeting healthy nutrition and physical activity in preschools is scarce. Purpose: To pilot test CATCH Early Childhood (CEC), a preschool-based nutrition and physical activity program among children ages three to five in Head Start. Methods: The study was conducted in two Head Start…
Imitative Modeling as a Theoretical Base for Instructing Language-Disordered Children
ERIC Educational Resources Information Center
Courtright, John A.; Courtright, Illene C.
1976-01-01
A modification of A. Bandura's social learning theory (imitative modeling) was employed as a theoretical base for language instruction with eight language disordered children (5 to 10 years old). (Author/SBH)
Kouloulias, Vassilis; Karanasiou, Irene; Giamalaki, Melina; Matsopoulos, George; Kouvaris, John; Kelekis, Nikolaos; Uzunoglu, Nikolaos
2015-02-01
A hyperthermia system using a folded loop antenna applicator at 27 MHz for soft tissue treatment was investigated both theoretically and experimentally to evaluate its clinical value. The electromagnetic analysis of a 27-MHz folded loop antenna for use in human tissue was based on a customised software tool and led to the design and development of the proposed hyperthermia system. The system was experimentally validated using specific absorption rate (SAR) distribution estimations through temperature distribution measurements of a muscle tissue phantom after electromagnetic exposure. Various scenarios for optimal antenna positioning were also performed. Comparison of the theoretical and experimental analysis results shows satisfactory agreement. The SAR level of 50% reaches 8 cm depth in the tissue phantom. Thus, based on the maximum observed SAR values that were of the order of 100 W/kg, the antenna specified is suitable for deep tumour heating. Theoretical and experimental SAR distribution results as derived from this study are in agreement. The proposed folded loop antenna seems appropriate for use in hyperthermia treatment, achieving proper planning and local treatment of deeply seated affected areas and lesions.
Theoretical studies on sRNA-mediated regulation in bacteria
NASA Astrophysics Data System (ADS)
Chang, Xiao-Xue; Xu, Liu-Fang; Shi, Hua-Lin
2015-12-01
Small RNA(sRNA)-mediated post-transcriptional regulation differs from protein-mediated regulation. Through base-pairing, sRNA can regulate the target mRNA in a catalytic or stoichiometric manner. Some theoretical models were built for comparison of the protein-mediated and sRNA-mediated modes in the steady-state behaviors and noise properties. Many experiments demonstrated that a single sRNA can regulate several mRNAs, which causes crosstalk between the targets. Here, we focus on some models in which two target mRNAs are silenced by the same sRNA to discuss their crosstalk features. Additionally, the sequence-function relationship of sRNA and its role in the kinetic process of base-pairing have been highlighted in model building. Project supported by the National Basic Research Program of China (Grant No. 2013CB834100), the National Natural Science Foundation of China (Grant Nos. 11121403 and 11274320), the Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Grant No. Y4KF171CJ1), the National Natural Science Foundation for Young Scholar of China (Grant No. 11304115), and the China Postdoctoral Science Foundation (Grant No. 2013M541282).
Gradient descent for robust kernel-based regression
NASA Astrophysics Data System (ADS)
Guo, Zheng-Chu; Hu, Ting; Shi, Lei
2018-06-01
In this paper, we study the gradient descent algorithm generated by a robust loss function over a reproducing kernel Hilbert space (RKHS). The loss function is defined by a windowing function G and a scale parameter σ, which can include a wide range of commonly used robust losses for regression. There is still a gap between theoretical analysis and optimization process of empirical risk minimization based on loss: the estimator needs to be global optimal in the theoretical analysis while the optimization method can not ensure the global optimality of its solutions. In this paper, we aim to fill this gap by developing a novel theoretical analysis on the performance of estimators generated by the gradient descent algorithm. We demonstrate that with an appropriately chosen scale parameter σ, the gradient update with early stopping rules can approximate the regression function. Our elegant error analysis can lead to convergence in the standard L 2 norm and the strong RKHS norm, both of which are optimal in the mini-max sense. We show that the scale parameter σ plays an important role in providing robustness as well as fast convergence. The numerical experiments implemented on synthetic examples and real data set also support our theoretical results.
ERIC Educational Resources Information Center
Biddle, Christopher J.
2013-01-01
The purpose of this qualitative holistic multiple-case study was to identify the optimal theoretical approach for a Counter-Terrorism Reality-Based Training (CTRBT) model to train post-9/11 police officers to perform effectively in their counter-terrorism assignments. Post-9/11 police officers assigned to counter-terrorism duties are not trained…
Roca, Judith; Reguant, Mercedes; Canet, Olga
2016-11-01
Teaching strategies are essential in order to facilitate meaningful learning and the development of high-level thinking skills in students. To compare three teaching methodologies (problem-based learning, case-based teaching and traditional methods) in terms of the learning outcomes achieved by nursing students. This quasi-experimental research was carried out in the Nursing Degree programme in a group of 74 students who explored the subject of The Oncology Patient through the aforementioned strategies. A performance test was applied based on Bloom's Revised Taxonomy. A significant correlation was found between the intragroup theoretical and theoretical-practical dimensions. Likewise, intergroup differences were related to each teaching methodology. Hence, significant differences were estimated between the traditional methodology (x-=9.13), case-based teaching (x-=12.96) and problem-based learning (x-=14.84). Problem-based learning was shown to be the most successful learning method, followed by case-based teaching and the traditional methodology. Copyright © 2016 Elsevier Ltd. All rights reserved.
Evidence-based psychosocial treatments for child and adolescent depression.
David-Ferdon, Corinne; Kaslow, Nadine J
2008-01-01
The evidence-base of psychosocial treatment outcome studies for depressed youth conducted since 1998 is examined. All studies for depressed children meet Nathan and Gorman's (2002) criteria for Type 2 studies whereas the adolescent protocols meet criteria for both Type 1 and Type 2 studies. Based on the Task Force on the Promotion and Dissemination of Psychological Procedures guidelines, the cognitive-behavioral therapy (CBT) based specific programs of Penn Prevention Program, Self-Control Therapy, and Coping with Depression-Adolescent are probably efficacious. Interpersonal Therapy-Adolescent, which falls under the theoretical category of interpersonal therapy (IPT), also is a probably efficacious treatment. CBT provided through the modalities of child group only and child group plus parent components are well-established intervention approaches for depressed children. For adolescents, two modalities are well-established (CBT adolescent only group, IPT individual), and three are probably efficacious (CBT adolescent group plus parent component, CBT individual, CBT individual plus parent/family component). From the broad theoretical level, CBT has well-established efficacy and behavior therapy meets criteria for a probably efficacious intervention for childhood depression. For adolescent depression, both CBT and IPT have well-established efficacy. Future research directions and best practices are offered.
Sponer, Jiří; Sponer, Judit E; Mládek, Arnošt; Jurečka, Petr; Banáš, Pavel; Otyepka, Michal
2013-12-01
Base stacking is a major interaction shaping up and stabilizing nucleic acids. During the last decades, base stacking has been extensively studied by experimental and theoretical methods. Advanced quantum-chemical calculations clarified that base stacking is a common interaction, which in the first approximation can be described as combination of the three most basic contributions to molecular interactions, namely, electrostatic interaction, London dispersion attraction and short-range repulsion. There is not any specific π-π energy term associated with the delocalized π electrons of the aromatic rings that cannot be described by the mentioned contributions. The base stacking can be rather reasonably approximated by simple molecular simulation methods based on well-calibrated common force fields although the force fields do not include nonadditivity of stacking, anisotropy of dispersion interactions, and some other effects. However, description of stacking association in condensed phase and understanding of the stacking role in biomolecules remain a difficult problem, as the net base stacking forces always act in a complex and context-specific environment. Moreover, the stacking forces are balanced with many other energy contributions. Differences in definition of stacking in experimental and theoretical studies are explained. Copyright © 2013 Wiley Periodicals, Inc.
Collaboration of Miniature Multi-Modal Mobile Smart Robots over a Network
2015-08-14
theoretical research on mathematics of failures in sensor-network-based miniature multimodal mobile robots and electromechanical systems. The views...theoretical research on mathematics of failures in sensor-network-based miniature multimodal mobile robots and electromechanical systems. The...independently evolving research directions based on physics-based models of mechanical, electromechanical and electronic devices, operational constraints
Coherent beam combination of fiber lasers with a strongly confined waveguide: numerical model.
Tao, Rumao; Si, Lei; Ma, Yanxing; Zhou, Pu; Liu, Zejin
2012-08-20
Self-imaging properties of fiber lasers in a strongly confined waveguide (SCW) and their application in coherent beam combination (CBC) are studied theoretically. Analytical formulas are derived for the positions, amplitudes, and phases of the N images at the end of an SCW, which is important for quantitative analysis of waveguide CBC. The formulas are verified with experimental results and numerical simulation of a finite difference beam propagation method (BPM). The error of our analytical formulas is less than 6%, which can be reduced to less than 1.5% with Goos-Hahnchen penetration depth considered. Based on the theoretical model and BPM, we studied the combination of two laser beams based on an SCW. The effects of the waveguide refractive index and Gaussian beam waist are studied. We also simulated the CBC of nine and 16 fiber lasers, and a single beam without side lobes was achieved.
Outcome regimes of binary raindrop collisions
NASA Astrophysics Data System (ADS)
Testik, Firat Y.
2009-11-01
This study delineates the physical conditions that are responsible for the occurrence of main outcome regimes (i.e., bounce, coalescence, and breakup) for binary drop collisions with a precipitation microphysics perspective. Physical considerations based on the collision kinetic energy and the surface energies of the colliding drops lead to the development of a theoretical regime diagram for the drop/raindrop collision outcomes in the We- p plane ( We — Weber number, p — raindrop diameter ratio). This theoretical regime diagram is supported by laboratory experimental observations of drop collisions using high-speed imaging. Results of this fundamental study bring in new insights into the quantitative understanding of drop dynamics, applications of which extend beyond precipitation microphysics. In particular, results of this drop collision study are expected to give impetus to the physics-based dynamic modeling of the drop size distributions that is essential for various typical modern engineering applications, including numerical modeling of evolution of raindrop size distribution in rain shaft.
Linking theory with qualitative research through study of stroke caregiving families.
Pierce, Linda L; Steiner, Victoria; Cervantez Thompson, Teresa L; Friedemann, Marie-Luise
2014-01-01
This theoretical article outlines the deliberate process of applying a qualitative data analysis method rooted in Friedemann's Framework of Systemic Organization through the study of a web-based education and support intervention for stroke caregiving families. Directed by Friedemann's framework, the analytic method involved developing, refining, and using a coding rubric to explore interactive patterns between caregivers and care recipients from this 3-month feasibility study using this education and support intervention. Specifically, data were gathered from the intervention's web-based discussion component between caregivers and the nurse specialist, as well as from telephone caregiver interviews. A theoretical framework guided the process of developing and refining this coding rubric for the purpose of organizing data; but, more importantly, guided the investigators' thought processes, allowing them to extract rich information from the data set, as well as synthesize this information to generate a broad understanding of the caring situation. © 2013 Association of Rehabilitation Nurses.
Shalviri, Gloria; Yazdizadeh, Bahareh; Mirbaha, Fariba; Gholami, Kheirollah; Majdzadeh, Reza
2018-01-01
Adverse drug events (ADEs) may cause serious injuries including death. Spontaneous reporting of ADEs plays a great role in detection and prevention of them; however, underreporting always exists. Although several interventions have been utilized to solve this problem, they are mainly based on experience and the rationale for choosing them has no theoretical base. The vast variety of behavioural theories makes it difficult to choose appropriate theory. Theoretical domains framework (TDF) is suggested as a solution. The objective of this study was to select the best theory for evaluating ADE reporting in hospitals based on TDF. We carried out three focus group discussions with hospital pharmacists and nurses, based on TDF questions. The analysis was performed through five steps including coding discussions transcript, extracting beliefs, selecting relevant domains, matching related constructs to the extracted beliefs, and determining the appropriate theories in each domain. The theory with the highest number of matched domains and constructs was selected as the theory of choice. A total of six domains were identified relevant to ADE reporting, including “Knowledge”, “Skills”, “Beliefs about consequences”, “Motivation and goals”, “Environmental context and resources” and “Social influences”. We found theory of planned behavior as the comprehensive theory to study factors influencing ADE reporting in hospitals, since it was relevant theory in five out of six relevant domains and the common theory in 55 out of 75 identified beliefs. In conclusion, we suggest theory of planned behavior for further studies on designing appropriate interventions to increase ADE reporting in hospitals. PMID:29881437
Shalviri, Gloria; Yazdizadeh, Bahareh; Mirbaha, Fariba; Gholami, Kheirollah; Majdzadeh, Reza
2018-01-01
Adverse drug events (ADEs) may cause serious injuries including death. Spontaneous reporting of ADEs plays a great role in detection and prevention of them; however, underreporting always exists. Although several interventions have been utilized to solve this problem, they are mainly based on experience and the rationale for choosing them has no theoretical base. The vast variety of behavioural theories makes it difficult to choose appropriate theory. Theoretical domains framework (TDF) is suggested as a solution. The objective of this study was to select the best theory for evaluating ADE reporting in hospitals based on TDF. We carried out three focus group discussions with hospital pharmacists and nurses, based on TDF questions. The analysis was performed through five steps including coding discussions transcript, extracting beliefs, selecting relevant domains, matching related constructs to the extracted beliefs, and determining the appropriate theories in each domain. The theory with the highest number of matched domains and constructs was selected as the theory of choice. A total of six domains were identified relevant to ADE reporting, including "Knowledge", "Skills", "Beliefs about consequences", "Motivation and goals", "Environmental context and resources" and "Social influences". We found theory of planned behavior as the comprehensive theory to study factors influencing ADE reporting in hospitals, since it was relevant theory in five out of six relevant domains and the common theory in 55 out of 75 identified beliefs. In conclusion, we suggest theory of planned behavior for further studies on designing appropriate interventions to increase ADE reporting in hospitals.
Approaches to Learning Information Literacy: A Phenomenographic Study
ERIC Educational Resources Information Center
Diehm, Rae-Anne; Lupton, Mandy
2012-01-01
This paper reports on an empirical study that explores the ways students approach learning to find and use information. Based on interviews with 15 education students in an Australian university, this study uses phenomenography as its methodological and theoretical basis. The study reveals that students use three main strategies for learning…
Foundations of Game-Based Learning
ERIC Educational Resources Information Center
Plass, Jan L.; Homer, Bruce D.; Kinzer, Charles K.
2015-01-01
In this article we argue that to study or apply games as learning environments, multiple perspectives have to be taken into account. We first define game-based learning and gamification, and then discuss theoretical models that describe learning with games, arguing that playfulness is orthogonal to learning theory. We then review design elements…
Students' Construction of External Representations in Design-Based Learning Situations
ERIC Educational Resources Information Center
de Vries, Erica
2006-01-01
This article develops a theoretical framework for the study of students' construction of mixed multiple external representations in design-based learning situations involving an adaptation of professional tasks and tools to a classroom setting. The framework draws on research on professional design processes and on learning with multiple external…
An Examination of Learning Profiles in Physical Education
ERIC Educational Resources Information Center
Shen, Bo; Chen, Ang
2007-01-01
Using the model of domain learning as a theoretical framework, the study was designed to examine the extent to which learners' initial learning profiles based on previously acquired knowledge, learning strategy application, and interest-based motivation were distinctive in learning softball. Participants were 177 sixth-graders from three middle…
Youth in the Workplace. The Dynamics of Learner Needs and Work Roles. Summary.
ERIC Educational Resources Information Center
Miguel, Richard J.
A two-year study addressed the problem of developing a typology of experiential education programs theoretically based and empirically tested that could guide systematic research on questions fundamental to workplace-based experiential education programs. The research question focused on was, "Can experiential education programs be classified…
Cooperative Learning: Improving University Instruction by Basing Practice on Validated Theory
ERIC Educational Resources Information Center
Johnson, David W.; Johnson, Roger T.; Smith, Karl A.
2014-01-01
Cooperative learning is an example of how theory validated by research may be applied to instructional practice. The major theoretical base for cooperative learning is social interdependence theory. It provides clear definitions of cooperative, competitive, and individualistic learning. Hundreds of research studies have validated its basic…
Understanding How Adolescents with Reading Difficulties Utilize Technology-Based Tools
ERIC Educational Resources Information Center
Marino, Matthew T.
2009-01-01
This article reports the findings from a study that examined how adolescent students with reading difficulties utilized cognitive tools that were embedded in a technology-based middle school science curriculum. The curriculum contained salient features of the Universal Design for Learning (UDL) theoretical framework. Sixteen general education…
Middle Atmosphere Program. Handbook for MAP, Volume 10
NASA Technical Reports Server (NTRS)
Taubenheim, J. (Editor)
1984-01-01
The contributions of ground based investigations to the study of middle atmospheric phenomena are addressed. General topics include diagnostics of the middle atmosphere from D region properties, winter anomaly, seasonal variations and disturbances, dynamics and theoretical models, ground based tracking of winds and waves, lower thermosphere phenomena, and solar-terrestrial influences.
The Role of Web-Based Simulations in Technology Education
ERIC Educational Resources Information Center
Page, Tom
2009-01-01
This paper discusses the theoretical underpinning and main aspects of the development and application of the web-orientation agent (WOA) and presents preliminary results concerning its use in university studies. The web-orientation agent (WOA) is a software based tool which produces an interactive learning environment offering support and guidance…
Gehrlach, Christoph; Güntert, Bernhard
2015-01-01
Patient satisfaction (PS) surveys are frequently used evaluation methods to show performance from the customer's view. This approach has some fundamental deficits, especially with respect to theory, methodology and usage. Because of the significant theoretical value of the expectation confirmation/disconfirmation concept in the development of PS, an expectation-based experience typology has been developed and tested to check whether this approach could be a theoretical and practical alternative to the survey of PS. Due to the mainly cognitive-rational process of comparison between expectations and expectation fulfilment, it is easier to make changes in this stage of the process than in the subsequent stage of the development of PS that is mainly based on emotional-affective processes. The paper contains a literature review of the common concept of PS and its causal and influencing factors. Based on the theoretical part of this study, an expectation-based experience typology was developed. In the next step, the typology was subjected to exploratory testing, based on two patient surveys. In some parts of the tested typology explorative differences could be found between hospitals. Despite this rather more complex and unusual approach to expectation-based experience typology, this concept offers the chance to change conditions not only retrospectively (based on data), but also in a prospective way in terms of a "management of expectations". Copyright © 2014. Published by Elsevier GmbH.
Moura, Silio Lima; Fajardo, Laura Martinez; Cunha, Leonardo Dos Anjos; Sotomayor, Maria Del Pilar Taboada; Machado, Francisco Bolivar Correto; Ferrão, Luiz Fernando Araújo; Pividori, Maria Isabel
2018-06-01
This study addresses the rational design of a magnetic molecularly imprinted polymer (magnetic-MIP) for the selective recognition of the hormone levothyroxine. The theoretical study was carried out by the density functional theory (DFT) computations considering dispersion interaction energies, and using the D2 Grimme's correction. The B97-D/def2-SV(P)/PCM method is used not only for studying the structure of the template the and monomer-monomer interactions, but also to assess the stoichiometry, noncovalent binding energies, solvation effects and thermodynamics properties such as binding energy. Among the 13 monomers studied in silico, itaconic acid is the most suitable according to the thermodynamic values. In order to assess the efficiency of the computational study, three different magnetic-MIPs based on itaconic acid, acrylic acid and acrylamide were synthesized and experimentally compared. The theoretical results are in agreement with experimental binding studies based on laser confocal microscopy, magneto-actuated immunoassay and electrochemical sensing. Furthermore, and for the first time, the direct electrochemical sensing of L-thyroxine preconcentrated on magnetic-MIP was successfully performed on magneto-actuated electrodes within 30 min with a limit of detection of as low as 0.0356 ng mL -1 which cover the clinical range of total L-thyroxine. Finally, the main analytical features were compared with the gold standard method based on commercial competitive immunoassays. This work provides a thoughtful strategy for magnetic molecularly imprinted polymer design, synthesis and application, opening new perspectives in the integration of these materials in magneto-actuated approaches for replacing specific antibodies in biosensors and microfluidic devices. Copyright © 2018 Elsevier B.V. All rights reserved.
Packaging consideration of two-dimensional polymer-based photonic crystals for laser beam steering
NASA Astrophysics Data System (ADS)
Dou, Xinyuan; Chen, Xiaonan; Chen, Maggie Yihong; Wang, Alan Xiaolong; Jiang, Wei; Chen, Ray T.
2009-02-01
In this paper, we report the theoretical study of polymer-based photonic crystals for laser beam steering which is based on the superprism effect as well as the experiment fabrication of the two dimensional photonic crystals for the laser beam steering. Superprism effect, the principle for beam steering, was separately studied in details through EFC (Equifrequency Contour) analysis. Polymer based photonic crystals were fabricated through double exposure holographic interference method using SU8-2007. The experiment results were also reported.
Travel into a fairy land: a critique of modern qualitative and mixed methods psychologies.
Toomela, Aaro
2011-03-01
In this article modern qualitative and mixed methods approaches are criticized from the standpoint of structural-systemic epistemology. It is suggested that modern qualitative methodologies suffer from several fallacies: some of them are grounded on inherently contradictory epistemology, the others ask scientific questions after the methods have been chosen, conduct studies inductively so that not only answers but even questions are often supposed to be discovered, do not create artificial situations and constraints on study-situations, are adevelopmental by nature, study not the external things and phenomena but symbols and representations--often the object of studies turns out to be the researcher rather than researched, rely on ambiguous data interpretation methods based to a large degree on feelings and opinions, aim to understand unique which is theoretically impossible, or have theoretical problems with sampling. Any one of these fallacies would be sufficient to exclude any possibility to achieve structural-systemic understanding of the studied things and phenomena. It also turns out that modern qualitative methodologies share several fallacies with the quantitative methodology. Therefore mixed methods approaches are not able to overcome the fundamental difficulties that characterize mixed methods taken separately. It is proposed that structural-systemic methodology that dominated psychological thought in the pre-WWII continental Europe is philosophically and theoretically better grounded than the other methodologies that can be distinguished in psychology today. Future psychology should be based on structural-systemic methodology.
A theoretical study of the electronic transition moment for the C2 Swan band system
NASA Technical Reports Server (NTRS)
Arnold, J. O.; Langhoff, S. R.
1978-01-01
Large-scale self-consistent-field plus configuration-interaction calculations have been performed for the a 3Pi u and d 3Pi g states of C2. The theoretical potential curves are in good agreement with those found by a Klein-Dunham analysis of measured molecular constants in terms of shape and excitation energy. The sum of the squares of the theoretical transition moments between the states at 2.44 bohr is 4.12 a.u. which agrees with the results of shock tube measurements. The variation in the sum of the squares of the theoretical moments with internuclear separation agrees with the values of Danylewych and Nicholls (1974). Based on the data for C2 and mother molecules, it is suggested that CI calculations using near Hartree-Fock quality Slater basis sets produce highly reliable transition moments.
Micro-satellite for space debris observation by optical sensors
NASA Astrophysics Data System (ADS)
Thillot, Marc; Brenière, Xavier; Midavaine, Thierry
2017-11-01
The purpose of this theoretical study carried out under CNES contract is to analyze the feasibility of small space debris detection and classification with an optical sensor on-board micro-satellite. Technical solutions based on active and passive sensors are analyzed and compared. For the most appropriated concept an optimization was made and theoretical performances in terms of number of detection versus class of diameter were calculated. Finally we give some preliminary physical sensor features to illustrate the concept (weight, volume, consumption,…).
A theoretical formulation of wave-vortex interactions
NASA Technical Reports Server (NTRS)
Wu, J. Z.; Wu, J. M.
1989-01-01
A unified theoretical formulation for wave-vortex interaction, designated the '(omega, Pi) framework,' is presented. Based on the orthogonal decomposition of fluid dynamic interactions, the formulation can be used to study a variety of problems, including the interaction of a longitudinal (acoustic) wave and/or transverse (vortical) wave with a main vortex flow. Moreover, the formulation permits a unified treatment of wave-vortex interaction at various approximate levels, where the normal 'piston' process and tangential 'rubbing' process can be approximated dfferently.
MOCVD grown InP-based materials and a LINK project involving TEM studies of non-planar and localized . M. Jones, Appl. Phys. Lett. 93 (2008) 123505. "Theoretical and experimental examination of the
McCalman, Janya; Tsey, Komla; Bainbridge, Roxanne; Shakeshaft, Anthony; Singleton, Michele; Doran, Christopher
2013-08-07
While Aboriginal Australian health providers prioritise identification of local community health needs and strategies, they do not always have the opportunity to access or interpret evidence-based literature to inform health improvement innovations. Research partnerships are therefore important when designing or modifying Aboriginal Australian health improvement initiatives and their evaluation. However, there are few models that outline the pragmatic steps by which research partners negotiate to develop, implement and evaluate community-based initiatives. The objective of this paper is to provide a theoretical model of the tailoring of health improvement initiatives by Aboriginal community-based service providers and partner university researchers. It draws from the case of the Beat da Binge community-initiated youth binge drinking harm reduction project in Yarrabah. A theoretical model was developed using the constructivist grounded theory methods of concurrent sampling, data collection and analysis. Data was obtained from the recordings of reflective Community-Based Participatory Research (CBPR) processes with Aboriginal community partners and young people, and university researchers. CBPR data was supplemented with interviews with theoretically sampled project participants. The transcripts of CBPR recordings and interviews were imported into NVIVO and coded to identify categories and theoretical constructs. The identified categories were then developed into higher order concepts and the relationships between concepts identified until the central purpose of those involved in the project and the core process that facilitated that purpose were identified. The tailored alcohol harm reduction project resulted in clarification of the underlying local determinants of binge drinking, and a shift in the project design from a social marketing awareness campaign (based on short-term events) to a more robust advocacy for youth mentoring into education, employment and training. The community-based process undertaken by the research partnership to tailor the design, implementation and evaluation of the project was theorised as a model incorporating four overlapping stages of negotiating knowledges and meanings to tailor a community response. The theoretical model can be applied in spaces where local Aboriginal and scientific knowledges meet to support the tailored design, implementation and evaluation of other health improvement projects, particularly those that originate from Aboriginal communities themselves.
2011-01-01
Background Tobacco use adversely affects oral health. Clinical guidelines recommend that dental providers promote tobacco abstinence and provide patients who use tobacco with brief tobacco use cessation counselling. Research shows that these guidelines are seldom implemented, however. To improve guideline adherence and to develop effective interventions, it is essential to understand provider behaviour and challenges to implementation. This study aimed to develop a theoretically informed measure for assessing among dental providers implementation difficulties related to tobacco use prevention and cessation (TUPAC) counselling guidelines, to evaluate those difficulties among a sample of dental providers, and to investigate a possible underlying structure of applied theoretical domains. Methods A 35-item questionnaire was developed based on key theoretical domains relevant to the implementation behaviours of healthcare providers. Specific items were drawn mostly from the literature on TUPAC counselling studies of healthcare providers. The data were collected from dentists (n = 73) and dental hygienists (n = 22) in 36 dental clinics in Finland using a web-based survey. Of 95 providers, 73 participated (76.8%). We used Cronbach's alpha to ascertain the internal consistency of the questionnaire. Mean domain scores were calculated to assess different aspects of implementation difficulties and exploratory factor analysis to assess the theoretical domain structure. The authors agreed on the labels assigned to the factors on the basis of their component domains and the broader behavioural and theoretical literature. Results Internal consistency values for theoretical domains varied from 0.50 ('emotion') to 0.71 ('environmental context and resources'). The domain environmental context and resources had the lowest mean score (21.3%; 95% confidence interval [CI], 17.2 to 25.4) and was identified as a potential implementation difficulty. The domain emotion provided the highest mean score (60%; 95% CI, 55.0 to 65.0). Three factors were extracted that explain 70.8% of the variance: motivation (47.6% of variance, α = 0.86), capability (13.3% of variance, α = 0.83), and opportunity (10.0% of variance, α = 0.71). Conclusions This study demonstrated a theoretically informed approach to identifying possible implementation difficulties in TUPAC counselling among dental providers. This approach provides a method for moving from diagnosing implementation difficulties to designing and evaluating interventions. PMID:21615948
On the spreading and instability of gravity current fronts of arbitrary shape
NASA Astrophysics Data System (ADS)
Zgheib, N.; Bonometti, T.; Balachandar, S.
2012-11-01
Experiments, simulations and theoretical analysis were carried out to study the influence of geometry on the spreading of gravity currents. The horizontal spreading of three different intial planforms of initial release were investigated: an extended ellipse, a cross, and a circle. The experiments used a pulley system for a swift nearly instantaneous release. The case of the axisymmetric cylinder compared favorably with earlier simulations. We ran experiments for multiple aspect ratios for all three configurations. Perhaps the most intriguing of the three cases is the ``ellipse,'' which within a short period of release flipped the major and minor axes. This behavior cannot be captured by current theoretical methods (such as the Box Model). These cases have also been investigated using shallow water and direct numerical simulations. Also, in this study, we investigate the possibility of a Rayleigh-Taylor (RT) instability of the radially moving, but decelerating front. We present a simple theoretical framework based on the inviscid Shallow Water Equations. The theoretical results are supplemented and compared to highly resolved three-dimensional simulations with the Boussinesq approximation. Chateaubriand Fellowship - NSF PIRE grant OISE-0968313.
Menichetti, Julia; Graffigna, Guendalina
2016-01-01
The increasing prevalence of chronic conditions among older adults constitutes a major public health problem. Thus, changes in lifestyles are required to prevent secondary conditions and sustain good care practices. While patient engagement received great attention in the last years as key strategy to solve this issue, to date no interventions exist to sustain the engagement of older chronic patients toward their health management. This study describes the design, development, and optimization of PHEinAction , a theoretically-driven intervention program to increase patient engagement in older chronic populations and consequently to foster healthy changes that can help reduce risks of health problems. The development process followed the UK Medical Research Council's (MRC) guidelines and involved selecting the theoretical base for the intervention, identifying the relevant evidence-based literature, and conducting exploratory research to qualitatively evaluate program's feasibility, acceptability, and comprehension. The result was a user-endorsed intervention designed to improve older patients' engagement in health management based on the theoretical framework of the Patient Health Engagement (PHE) model. The intervention program, which emerged from this process, consisted of 2 monthly face-to-face 1-h sessions delivered by a trained facilitator and one brief telephonic consultation, and aimed to facilitate a range of changes for patient engagement (e.g., motivation to change, health information seeking and use, emotional adjustment, health behaviors planning). PHEinAction is the first example of a theoretically-based patient engagement intervention designed for older chronic targets. The intervention program is based on psychological theory and evidence; it facilitates emotional, psychological, and behavioral processes to support patient engagement and lifestyle change and maintenance. It provides estimates of the extent to which it could help high-risk groups engage in effective health management and informs future trials.
Menichetti, Julia; Graffigna, Guendalina
2016-01-01
The increasing prevalence of chronic conditions among older adults constitutes a major public health problem. Thus, changes in lifestyles are required to prevent secondary conditions and sustain good care practices. While patient engagement received great attention in the last years as key strategy to solve this issue, to date no interventions exist to sustain the engagement of older chronic patients toward their health management. This study describes the design, development, and optimization of PHEinAction, a theoretically-driven intervention program to increase patient engagement in older chronic populations and consequently to foster healthy changes that can help reduce risks of health problems. The development process followed the UK Medical Research Council's (MRC) guidelines and involved selecting the theoretical base for the intervention, identifying the relevant evidence-based literature, and conducting exploratory research to qualitatively evaluate program's feasibility, acceptability, and comprehension. The result was a user-endorsed intervention designed to improve older patients' engagement in health management based on the theoretical framework of the Patient Health Engagement (PHE) model. The intervention program, which emerged from this process, consisted of 2 monthly face-to-face 1-h sessions delivered by a trained facilitator and one brief telephonic consultation, and aimed to facilitate a range of changes for patient engagement (e.g., motivation to change, health information seeking and use, emotional adjustment, health behaviors planning). PHEinAction is the first example of a theoretically-based patient engagement intervention designed for older chronic targets. The intervention program is based on psychological theory and evidence; it facilitates emotional, psychological, and behavioral processes to support patient engagement and lifestyle change and maintenance. It provides estimates of the extent to which it could help high-risk groups engage in effective health management and informs future trials. PMID:27695435
Empathy and child neglect: a theoretical model.
De Paul, Joaquín; Guibert, María
2008-11-01
To present an explanatory theory-based model of child neglect. This model does not address neglectful behaviors of parents with mental retardation, alcohol or drug abuse, or severe mental health problems. In this model parental behavior aimed to satisfy a child's need is considered a helping behavior and, as a consequence, child neglect is considered as a specific type of non-helping behavior. The central hypothesis of the theoretical model presented here suggests that neglectful parents cannot develop the helping response set to care for their children because the observation of a child's signal of need does not lead to the experience of emotions that motivate helping or because the parents experience these emotions, but specific cognitions modify the motivation to help. The present theoretical model suggests that different typologies of neglectful parents could be developed based on different reasons that parents might not to experience emotions that motivate helping behaviors. The model can be helpful to promote new empirical studies about the etiology of different groups of neglectful families.
NASA Astrophysics Data System (ADS)
Chen, Shichao; Zhu, Yizheng
2017-02-01
Sensitivity is a critical index to measure the temporal fluctuation of the retrieved optical pathlength in quantitative phase imaging system. However, an accurate and comprehensive analysis for sensitivity evaluation is still lacking in current literature. In particular, previous theoretical studies for fundamental sensitivity based on Gaussian noise models are not applicable to modern cameras and detectors, which are dominated by shot noise. In this paper, we derive two shot noiselimited theoretical sensitivities, Cramér-Rao bound and algorithmic sensitivity for wavelength shifting interferometry, which is a major category of on-axis interferometry techniques in quantitative phase imaging. Based on the derivations, we show that the shot noise-limited model permits accurate estimation of theoretical sensitivities directly from measured data. These results can provide important insights into fundamental constraints in system performance and can be used to guide system design and optimization. The same concepts can be generalized to other quantitative phase imaging techniques as well.
Theory and applications of structured light single pixel imaging
NASA Astrophysics Data System (ADS)
Stokoe, Robert J.; Stockton, Patrick A.; Pezeshki, Ali; Bartels, Randy A.
2018-02-01
Many single-pixel imaging techniques have been developed in recent years. Though the methods of image acquisition vary considerably, the methods share unifying features that make general analysis possible. Furthermore, the methods developed thus far are based on intuitive processes that enable simple and physically-motivated reconstruction algorithms, however, this approach may not leverage the full potential of single-pixel imaging. We present a general theoretical framework of single-pixel imaging based on frame theory, which enables general, mathematically rigorous analysis. We apply our theoretical framework to existing single-pixel imaging techniques, as well as provide a foundation for developing more-advanced methods of image acquisition and reconstruction. The proposed frame theoretic framework for single-pixel imaging results in improved noise robustness, decrease in acquisition time, and can take advantage of special properties of the specimen under study. By building on this framework, new methods of imaging with a single element detector can be developed to realize the full potential associated with single-pixel imaging.
Yang, Sheng-Sung; Ho, Chia-Lu; Siu, Sammy
2010-12-01
In this paper, we propose an algorithm based on the central limit theorem to compute the sensitivity of the multilayer perceptron (MLP) due to the errors of the inputs and weights. For simplicity and practicality, all inputs and weights studied here are independently identically distributed (i.i.d.). The theoretical results derived from the proposed algorithm show that the sensitivity of the MLP is affected by the number of layers and the number of neurons adopted in each layer. To prove the reliability of the proposed algorithm, some experimental results of the sensitivity are also presented, and they match the theoretical ones. The good agreement between the theoretical results and the experimental results verifies the reliability and feasibility of the proposed algorithm. Furthermore, the proposed algorithm can also be applied to compute precisely the sensitivity of the MLP with any available activation functions and any types of i.i.d. inputs and weights.
Intellect: a theoretical framework for personality traits related to intellectual achievements.
Mussel, Patrick
2013-05-01
The present article develops a theoretical framework for the structure of personality traits related to intellectual achievements. We postulate a 2-dimensional model, differentiating between 2 processes (Seek and Conquer) and 3 operations (Think, Learn, and Create). The framework was operationalized by a newly developed measure, which was validated based on 2 samples. Subsequently, in 3 studies (overall N = 1,478), the 2-dimensional structure of the Intellect framework was generally supported. Additionally, subdimensions of the Intellect framework specifically predicted conceptually related criteria, including scholastic performance, vocational interest, and leisure activities. Furthermore, results from multidimensional scaling and higher order confirmatory factor analyses show that the framework allows for the incorporation of several constructs that have been proposed on different theoretical backgrounds, such as need for cognition, typical intellectual engagement, curiosity, intrinsic motivation, goal orientation, and openness to ideas. It is concluded that based on the Intellect framework, these constructs, which have been researched separately in the literature, can be meaningfully integrated.
Hatlevik, Ida Katrine Riksaasen
2012-04-01
This paper is a report of a correlational study of the relations of nursing students' acquired reflective skills, practical skills and theoretical knowledge on their perception of coherence between theory and practice. Reflection is considered a key factor in bridging the gap between theory and practice. However, it is not evident whether reflective skills are primarily generic in nature or whether they develop from a theoretical knowledge base or the acquisition of practical skills. This study is a secondary analysis of existing data. The data are part of a student survey that was conducted among third-year nursing students in Norway during the spring of 2007. A total of 446 nursing students participated in this study and the response rate was 71%. Structural equation modelling analyses were performed. The results indicate that students' perception of coherence between theory and practice during initial nursing education is directly influenced by reflective skills and theoretical knowledge. The results also reveal that reflective skills have mediating effects and that practical skills have a fully mediated and theoretical knowledge a partially mediated influence on students' perception of coherence. The findings imply that helping students perceive coherence between theory and practice in nursing education, developing students' reflective skills and strengthening the theoretical components of the initial nursing education programme might be beneficial. The results suggest that reflective thinking is not merely a generic skill but rather a skill that depends on the acquisition of relevant professional knowledge and experience. © 2011 Blackwell Publishing Ltd.
Sun, Chunran; Wang, Muguang; Jian, Shuisheng
2017-08-21
In this paper, a novel quasi-fan Solc structure filter based on elliptical-core spun fiber for twist sensing has been experimentally investigated and theoretically analyzed. The discrete model of spun fiber has been built to analyze the transmission characteristics of proposed sensor. Both experimental and simulated results indicate that the extinction ratio of the comb spectrum based on quasi-fan Solc birefringent fiber filter varies with twist angle and agrees well with each other. Based on the intensity modulation, the proposed twist sensor exhibits a high sensitivity of 0.02219 dB/(°/m). Moreover, thanks to the invariability of the fiber birefringence and the state of polarization of the input light, the proposed twist sensor has a very low temperature and strain sensitivity, which can avoid the cross-sensitivity problem existing in most twist sensors.
a Protocol for High-Accuracy Theoretical Thermochemistry
NASA Astrophysics Data System (ADS)
Welch, Bradley; Dawes, Richard
2017-06-01
Theoretical studies of spectroscopy and reaction dynamics including the necessary development of potential energy surfaces rely on accurate thermochemical information. The Active Thermochemical Tables (ATcT) approach by Ruscic^{1} incorporates data for a large number of chemical species from a variety of sources (both experimental and theoretical) and derives a self-consistent network capable of making extremely accurate estimates of quantities such as temperature dependent enthalpies of formation. The network provides rigorous uncertainties, and since the values don't rely on a single measurement or calculation, the provenance of each quantity is also obtained. To expand and improve the network it is desirable to have a reliable protocol such as the HEAT approach^{2} for calculating accurate theoretical data. Here we present and benchmark an approach based on explicitly-correlated coupled-cluster theory and vibrational perturbation theory (VPT2). Methyldioxy and Methyl Hydroperoxide are important and well-characterized species in combustion processes and begin the family of (ethyl-, propyl-based, etc) similar compounds (much less is known about the larger members). Accurate anharmonic frequencies are essential to accurately describe even the 0 K enthalpies of formation, but are especially important for finite temperature studies. Here we benchmark the spectroscopic and thermochemical accuracy of the approach, comparing with available data for the smallest systems, and comment on the outlook for larger systems that are less well-known and characterized. ^{1}B. Ruscic, Active Thermochemical Tables (ATcT) values based on ver. 1.118 of the Thermochemical Network (2015); available at ATcT.anl.gov ^{2}A. Tajti, P. G. Szalay, A. G. Császár, M. Kállay, J. Gauss, E. F. Valeev, B. A. Flowers, J. Vázquez, and J. F. Stanton. JCP 121, (2004): 11599.
New robust statistical procedures for the polytomous logistic regression models.
Castilla, Elena; Ghosh, Abhik; Martin, Nirian; Pardo, Leandro
2018-05-17
This article derives a new family of estimators, namely the minimum density power divergence estimators, as a robust generalization of the maximum likelihood estimator for the polytomous logistic regression model. Based on these estimators, a family of Wald-type test statistics for linear hypotheses is introduced. Robustness properties of both the proposed estimators and the test statistics are theoretically studied through the classical influence function analysis. Appropriate real life examples are presented to justify the requirement of suitable robust statistical procedures in place of the likelihood based inference for the polytomous logistic regression model. The validity of the theoretical results established in the article are further confirmed empirically through suitable simulation studies. Finally, an approach for the data-driven selection of the robustness tuning parameter is proposed with empirical justifications. © 2018, The International Biometric Society.
Raedeke, Thomas D; Dlugonski, Deirdre
2017-12-01
This study was designed to compare a low versus high theoretical fidelity pedometer intervention applying social-cognitive theory on step counts and self-efficacy. Fifty-six public university employees participated in a 10-week randomized controlled trial with 2 conditions that varied in theoretical fidelity. Participants in the high theoretical fidelity condition wore a pedometer and participated in a weekly group walk followed by a meeting to discuss cognitive-behavioral strategies targeting self-efficacy. Participants in the low theoretical fidelity condition met for a group walk and also used a pedometer as a motivational tool and to monitor steps. Step counts were assessed throughout the 10-week intervention and after a no-treatment follow-up (20 weeks and 30 weeks). Self-efficacy was measured preintervention and postintervention. Participants in the high theoretical fidelity condition increased daily steps by 2,283 from preintervention to postintervention, whereas participants in the low fidelity condition demonstrated minimal change during the same time period (p = .002). Individuals attending at least 80% of the sessions in the high theoretical fidelity condition showed an increase of 3,217 daily steps (d = 1.03), whereas low attenders increased by 925 (d = 0.40). Attendance had minimal impact in the low theoretical fidelity condition. Follow-up data revealed that step counts were at least somewhat maintained. For self-efficacy, participants in the high, compared with those in the low, theoretical fidelity condition showed greater improvements. Findings highlight the importance of basing activity promotion efforts on theory. The high theoretical fidelity intervention that included cognitive-behavioral strategies targeting self-efficacy was more effective than the low theoretical fidelity intervention, especially for those with high attendance.
ERIC Educational Resources Information Center
Cardenas-Claros, Monica Stella; Gruba, Paul A.
2013-01-01
This paper proposes a theoretical framework for the conceptualization and design of help options in computer-based second language (L2) listening. Based on four empirical studies, it aims at clarifying both conceptualization and design (CoDe) components. The elements of conceptualization consist of a novel four-part classification of help options:…
Tavender, Emma J; Bosch, Marije; Gruen, Russell L; Green, Sally E; Michie, Susan; Brennan, Sue E; Francis, Jill J; Ponsford, Jennie L; Knott, Jonathan C; Meares, Sue; Smyth, Tracy; O'Connor, Denise A
2015-05-25
Despite the availability of evidence-based guidelines for the management of mild traumatic brain injury in the emergency department (ED), variations in practice exist. Interventions designed to implement recommended behaviours can reduce this variation. Using theory to inform intervention development is advocated; however, there is no consensus on how to select or apply theory. Integrative theoretical frameworks, based on syntheses of theories and theoretical constructs relevant to implementation, have the potential to assist in the intervention development process. This paper describes the process of applying two theoretical frameworks to investigate the factors influencing recommended behaviours and the choice of behaviour change techniques and modes of delivery for an implementation intervention. A stepped approach was followed: (i) identification of locally applicable and actionable evidence-based recommendations as targets for change, (ii) selection and use of two theoretical frameworks for identifying barriers to and enablers of change (Theoretical Domains Framework and Model of Diffusion of Innovations in Service Organisations) and (iii) identification and operationalisation of intervention components (behaviour change techniques and modes of delivery) to address the barriers and enhance the enablers, informed by theory, evidence and feasibility/acceptability considerations. We illustrate this process in relation to one recommendation, prospective assessment of post-traumatic amnesia (PTA) by ED staff using a validated tool. Four recommendations for managing mild traumatic brain injury were targeted with the intervention. The intervention targeting the PTA recommendation consisted of 14 behaviour change techniques and addressed 6 theoretical domains and 5 organisational domains. The mode of delivery was informed by six Cochrane reviews. It was delivered via five intervention components : (i) local stakeholder meetings, (ii) identification of local opinion leader teams, (iii) a train-the-trainer workshop for appointed local opinion leaders, (iv) local training workshops for delivery by trained local opinion leaders and (v) provision of tools and materials to prompt recommended behaviours. Two theoretical frameworks were used in a complementary manner to inform intervention development in managing mild traumatic brain injury in the ED. The effectiveness and cost-effectiveness of the developed intervention is being evaluated in a cluster randomised trial, part of the Neurotrauma Evidence Translation (NET) program.
Yardley, Sarah; Brosnan, Caragh; Richardson, Jane
2013-01-01
Theoretical integration is a necessary element of study design if clarification of experiential learning is to be achieved. There are few published examples demonstrating how this can be achieved. This methodological article provides a worked example of research methodology that achieved clarification of authentic early experiences (AEEs) through a bi-directional approach to theory and data. Bi-directional refers to our simultaneous use of theory to guide and interrogate empirical data and the use of empirical data to refine theory. We explain the five steps of our methodological approach: (1) understanding the context; (2) critique on existing applications of socio-cultural models to inform study design; (3) data generation; (4) analysis and interpretation and (5) theoretical development through a novel application of Metis. These steps resulted in understanding of how and why different outcomes arose from students participating in AEE. Our approach offers a mechanism for clarification without which evidence-based effective ways to maximise constructive learning cannot be developed. In our example it also contributed to greater theoretical understanding of the influence of social interactions. By sharing this example of research undertaken to develop both theory and educational practice we hope to assist others seeking to conduct similar research.
Ethnomathematics in Perspective of Sundanese Culture
ERIC Educational Resources Information Center
Abdullah, Atje Setiawan
2017-01-01
This study is an exploratory research aims to find and know about a phenomenon by exploration. Therefore, the approach used in this study is ethnographic approach, an empirical and theoretical approach to get description and deep analysis about a culture based on field study. From the sustainable interviews and confirmation about field research…
ERIC Educational Resources Information Center
Tupou, Samuel F.
2013-01-01
This study examines teacher efficacy within the context of professional development to understand the relationship between teacher efficacy and teacher collaboration. Two theoretical frameworks framed this teacher efficacy study based on "locus of control" and "social cognitive theory." A 29-item questionnaire was e-mailed to…
Compound Complementarities in the Study of Motivated Behavior.
ERIC Educational Resources Information Center
Teitelbaum, Philip; Stricker, Edward M.
1994-01-01
The 1954 article by Eliot Stellar provided the theoretical focus for a great deal of research on the biological bases of human behavior. Future attention to the infrastructure of behaviors being studied, combined with reductionistic studies of neurons, will fulfill the potential contribution to behavioral neuroscience implicit in Stellar's…
The dynamic deformation of a layered viscoelastic medium under surface excitation
NASA Astrophysics Data System (ADS)
Aglyamov, Salavat R.; Wang, Shang; Karpiouk, Andrei B.; Li, Jiasong; Twa, Michael; Emelianov, Stanislav Y.; Larin, Kirill V.
2015-06-01
In this study the dynamic behavior of a layered viscoelastic medium in response to the harmonic and impulsive acoustic radiation force applied to its surface was investigated both theoretically and experimentally. An analytical solution for a layered viscoelastic compressible medium in frequency and time domains was obtained using the Hankel transform. A special incompressible case was considered to model soft biological tissues. To verify our theoretical model, experiments were performed using tissue-like gel-based phantoms with varying mechanical properties. A 3.5 MHz single-element focused ultrasound transducer was used to apply the radiation force at the surface of the phantoms. A phase-sensitive optical coherence tomography system was used to track the displacements of the phantom surface. Theoretically predicted displacements were compared with experimental measurements. The role of the depth dependence of the elastic properties of a medium in its response to an acoustic pulse at the surface was studied. It was shown that the low-frequency vibrations at the surface are more sensitive to the deep layers than high-frequency ones. Therefore, the proposed model in combination with spectral analysis can be used to evaluate depth-dependent distribution of the mechanical properties based on the measurements of the surface deformation.
Experimental and Theoretical Study of Propeller Spinner/Shank Interference. M.S. Thesis
NASA Technical Reports Server (NTRS)
Cornell, C. C.
1986-01-01
A fundamental experimental and theoretical investigation into the aerodynamic interference associated with propeller spinner and shank regions was conducted. The research program involved a theoretical assessment of solutions previously proposed, followed by a systematic experimental study to supplement the existing data base. As a result, a refined computational procedure was established for prediction of interference effects in terms of interference drag and resolved into propeller thrust and torque components. These quantities were examined with attention to engineering parameters such as two spinner finess ratios, three blade shank forms, and two/three/four/six/eight blades. Consideration of the physics of the phenomena aided in the logical deduction of two individual interference quantities (cascade effects and spinner/shank juncture interference). These interference effects were semi-empirically modeled using existing theories and placed into a compatible form with an existing propeller performance scheme which provided the basis for examples of application.
Ferreira, Fernanda Rosche; Mendes, Fausto Medeiros; Raggio, Daniela Prócida; Imparato, José Carlos; Bonecker, Marcelo; Magalhães, Ana Carolina; Wang, Linda; Rios, Daniela; Pessan, Juliano Pelim; Duque, Cristiane; Rebelo, Maria Augusta Bessa; Alves Filho, Ary Oliveira; Lima, Marina De Deus Moura; Moura, Marcoeli Silva; De Carli, Alessandro Diogo; Sanabe, Mariane Emi; Cenci, Maximiliano Sergio; Oliveira, Elenara Ferreira; Correa, Marcos Britto; Rocha, Rachel Oliveira; Zenkner, Julio Eduardo; Murisí, Pedroza Uribe; Martignon, Stefania; Lara, Juan Sebastian; Aquino, Fatima Gabriela; Carrillo, Alfredo; Chu, Chun Hung; Deery, Chris; Ricketts, David; Melo, Paulo; Antunes, José Leopoldo Ferreira; Ekstrand, Kim Rud
2017-01-01
Background Tutored laboratorial activities could be a manner of improving the competency development of students. However, its impact over conventional theoretical classes has not yet been tested. Additionally, different university contexts could influence this issue and should be explored. Objective To assess the impact of a tutored theoretical-practical training for teaching undergraduate students to detect caries lesions as compared with theoretical teaching activities. The impact of these teaching/learning activities will be assessed in terms of efficacy, cost/benefit, retention of knowledge/acquired competences, and student acceptability. Methods Sixteen centers (7 centers from Brazil and 9 centers from other countries throughout the world) are involved in the inclusion of subjects for this protocol. A randomized controlled study with parallel groups will be conducted. One group (control) will be exposed to a 60- to 90-minute conventional theoretical class and the other group (test) will be exposed to the same theoretical class and also a 90-minute laboratory class, including exercises and discussions based on the evaluation of a pool of images and extracted teeth. The mentioned outcomes will be evaluated immediately after the teaching activities and also in medium- and long-term analyses. To compare the long-term outcomes, students who enrolled in the university before the participating students will be interviewed for data collection and these data will be used as a control and compared with the trained group. This stage will be a nonrandomized phase of this study, nested in the main study. Appropriate statistical analysis will be performed according to the aims of this study. Variables related to the centers will also be analyzed and used to model adjustment as possible sources of variability among results. Results This ongoing study is funded by a Brazilian national funding agency (CNPq- 400736/2014-4). We expect that the tutored theoretical-practical training will improve the undergraduate students’ performance in the detection of caries lesions and subsequent treatment decisions, mainly in terms of long-term retention of knowledge. Our hypothesis is that tutored theoretical-practical training is a more cost-effective option for teaching undergraduate students to detect caries lesions. Conclusions If our hypothesis is confirmed, the use of laboratory training in conjunction with theoretical classes could be used as an educational strategy in Cariology to improve the development of undergraduate students’ skills in the detection of caries lesions and clinical decision-making. PMID:28814381
Huckans, Marilyn; Hutson, Lee; Twamley, Elizabeth; Jak, Amy; Kaye, Jeffrey; Storzbach, Daniel
2013-01-01
Objective To evaluate the efficacy of cognitive rehabilitation therapies (CRTs) for mild cognitive impairment (MCI). Our review revealed a need for evidence-based treatments for MCI and a lack of a theoretical rehabilitation model to guide the development and evaluation of these interventions. We have thus proposed a theoretical rehabilitation model of MCI that yields key intervention targets - cognitive compromise, functional compromise, neuropsychiatric symptoms, and modifiable risk and protective factors known to be associated with MCI and dementia. Our model additionally defines specific cognitive rehabilitation approaches that may directly or indirectly target key outcomes - restorative cognitive training, compensatory cognitive training, lifestyle interventions, and psychotherapeutic techniques. Methods Fourteen randomized controlled trials met inclusion criteria and were reviewed. Results Studies markedly varied in terms of intervention approaches and selected outcome measures and were frequently hampered by design limitations. The bulk of the evidence suggested that CRTs can change targeted behaviors in individuals with MCI and that CRTs are associated with improvements in objective cognitive performance, but the pattern of effects on specific cognitive domains was inconsistent across studies. Other important outcomes (i.e., daily functioning, quality of life, neuropsychiatric symptom severity) were infrequently assessed across studies. Few studies evaluated long-term outcomes or the impact of CRTs on conversion rates from MCI to dementia or normal cognition. Conclusions Overall, results from trials are promising but inconclusive. Additional well-designed and adequately powered trials are warranted and required before CRTs for MCI can be considered evidence based. PMID:23471631
Theoretical rationale for music selection in oncology intervention research: an integrative review.
Burns, Debra S
2012-01-01
Music-based interventions have helped patients with cancer improve their quality of life, decrease treatment related distress, and manage pain. However, quantitative findings from music intervention studies are inconsistent. The purpose of this review was to explore the theoretical underpinnings for the selection of the music stimuli used to influence targeted outcomes. It was hypothesized that disparate findings were due in part to the atheoretical nature of music selection and the resulting diversity in music stimuli between and within studies. A systematic research synthesis including a comprehensive database and reference list search resulted in 22 studies. Included studies were compiled into two tables cataloging intervention theory, intervention content, and outcomes. A majority of studies did not provide a rationale or intervention theory for the delivery of music or choice of outcomes. Recorded music was the most common delivery method, but the specific music was rarely included within the report. Only two studies that included a theoretical framework reported null results on at least some of the outcomes. Null results are partially explained by an incomplete or mismatch in intervention theory and music selection and delivery. While the inclusion of an intervention theory does not guarantee positive results, including a theoretical rationale for the use of music, particular therapeutic processes or mechanisms, and the specifics of how music is selected and delivered increases scientific rigor and the probability of clinical translation.
The cosmological lithium problem revisited
NASA Astrophysics Data System (ADS)
Bertulani, C. A.; Mukhamedzhanov, A. M.; Shubhchintak
2016-07-01
After a brief review of the cosmological lithium problem, we report a few recent attempts to find theoretical solutions by our group at Texas A&M University (Commerce & College Station). We will discuss our studies on the theoretical description of electron screening, the possible existence of parallel universes of dark matter, and the use of non-extensive statistics during the Big Bang nucleosynthesis epoch. Last but not least, we discuss possible solutions within nuclear physics realm. The impact of recent measurements of relevant nuclear reaction cross sections for the Big Bang nucleosynthesis based on indirect methods is also assessed. Although our attempts may not able to explain the observed discrepancies between theory and observations, they suggest theoretical developments that can be useful also for stellar nucleosynthesis.
Shang, Xuefang; Zhao, Yuan; Wei, Xiaofang; Feng, Yaqian; Li, Xin; Gao, Shuyan; Xu, Xiufang
2015-01-01
New phenanthroline derivatives (1, 2, 3, 4) containing phenol groups have been synthesized and optimized. The nano-material of compound 2 was also developed. Their binding properties were evaluated for various biological anions (F(-), Cl(-), Br(-), I(-), AcO(-) and H(2)PO(4)(-)) by theoretical investigation, UV-vis, fluorescence, (1)HNMR titration experiments and these compounds all showed strong binding ability for AcO(-) without the interference of other anions tested. The anion binding ability could be regularized by electron push-pull properties of the ortho- or para- substituent on benzene. Theoretical investigation analysis revealed the effect of intramolecular hydrogen bond existed between -OH and other atoms in the structure of these compounds.
Charting the future course of rural health and remote health in Australia: Why we need theory.
Bourke, Lisa; Humphreys, John S; Wakerman, John; Taylor, Judy
2010-04-01
This paper argues that rural and remote health is in need of theoretical development. Based on the authors' discussions, reflections and critical analyses of literature, this paper proposes key reasons why rural and remote health warrants the development of theoretical frameworks. The paper cites five reasons why theory is needed: (i) theory provides an approach for how a topic is studied; (ii) theory articulates key assumptions in knowledge development; (iii) theory systematises knowledge, enabling it to be transferable; (iv) theory provides predictability; and (v) theory enables comprehensive understanding. This paper concludes with a call for theoretical development in both rural and remote health to expand its knowledge and be more relevant to improving health care for rural Australians.
NASA Astrophysics Data System (ADS)
Bonetto, P.; Qi, Jinyi; Leahy, R. M.
2000-08-01
Describes a method for computing linear observer statistics for maximum a posteriori (MAP) reconstructions of PET images. The method is based on a theoretical approximation for the mean and covariance of MAP reconstructions. In particular, the authors derive here a closed form for the channelized Hotelling observer (CHO) statistic applied to 2D MAP images. The theoretical analysis models both the Poission statistics of PET data and the inhomogeneity of tracer uptake. The authors show reasonably good correspondence between these theoretical results and Monte Carlo studies. The accuracy and low computational cost of the approximation allow the authors to analyze the observer performance over a wide range of operating conditions and parameter settings for the MAP reconstruction algorithm.
Lüdecke, Daniel
2014-01-01
Introduction Health care providers seek to improve patient-centred care. Due to fragmentation of services, this can only be achieved by establishing integrated care partnerships. The challenge is both to control costs while enhancing the quality of care and to coordinate this process in a setting with many organisations involved. The problem is to establish control mechanisms, which ensure sufficiently consideration of patient centredness. Theory and methods Seventeen qualitative interviews have been conducted in hospitals of metropolitan areas in northern Germany. The documentary method, embedded into a systems theoretical framework, was used to describe and analyse the data and to provide an insight into the specific perception of organisational behaviour in integrated care. Results The findings suggest that integrated care partnerships rely on networks based on professional autonomy in the context of reliability. The relationships of network partners are heavily based on informality. This correlates with a systems theoretical conception of organisations, which are assumed autonomous in their decision-making. Conclusion and discussion Networks based on formal contracts may restrict professional autonomy and competition. Contractual bindings that suppress the competitive environment have negative consequences for patient-centred care. Drawbacks remain due to missing self-regulation of the network. To conclude, less regimentation of integrated care partnerships is recommended. PMID:25411573
Ghisi, Gabriela Lima de Melo; Grace, Sherry L; Thomas, Scott; Oh, Paul
2015-05-01
To (1) test the effect of a health action process approach (HAPA) theory-based education program in cardiac rehabilitation (CR) compared to traditional education on patient knowledge and HAPA constructs; and, (2) investigate the theoretical correlates of exercise behavior among CR patients receiving theory-based education. CR patients were exposed to an existing or HAPA-based 6 month education curriculum in this quasi-experimental study. Participants completed a survey assessing exercise behavior, HAPA constructs, and knowledge pre and post-program. 306 patients consented to participate, of which 146 (47.7%) were exposed to the theory-based educational curriculum. There was a significant improvement in patients' overall knowledge pre- to post-CR, as well as in some HAPA constructs and exercise behavior, regardless of curriculum (p < 0.05). Path analysis revealed that knowledge was significantly related to intention formation, and intentions to engage in exercise were not directly related to behavior, which required action planning. The theoretically-informed education curriculum was not associated with greater knowledge or exercise behavior as expected. Education in CR improves knowledge, and theoretical constructs related to exercise behavior. Educational curricula should be designed to not only increase patients' knowledge, but also enhance intentions, self-efficacy, and action planning. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Lüdecke, Daniel
2014-10-01
Health care providers seek to improve patient-centred care. Due to fragmentation of services, this can only be achieved by establishing integrated care partnerships. The challenge is both to control costs while enhancing the quality of care and to coordinate this process in a setting with many organisations involved. The problem is to establish control mechanisms, which ensure sufficiently consideration of patient centredness. Seventeen qualitative interviews have been conducted in hospitals of metropolitan areas in northern Germany. The documentary method, embedded into a systems theoretical framework, was used to describe and analyse the data and to provide an insight into the specific perception of organisational behaviour in integrated care. The findings suggest that integrated care partnerships rely on networks based on professional autonomy in the context of reliability. The relationships of network partners are heavily based on informality. This correlates with a systems theoretical conception of organisations, which are assumed autonomous in their decision-making. Networks based on formal contracts may restrict professional autonomy and competition. Contractual bindings that suppress the competitive environment have negative consequences for patient-centred care. Drawbacks remain due to missing self-regulation of the network. To conclude, less regimentation of integrated care partnerships is recommended.
Katsogiannis, Konstantinos Alexandros G; Vladisavljević, Goran T; Georgiadou, Stella; Rahmani, Ramin
2016-10-26
The effect of pore induction on increasing electrospun fibrous network specific surface area was investigated in this study. Theoretical models based on the available surface area of the fibrous network and exclusion of the surface area lost due to fiber-to-fiber contacts were developed. The models for calculation of the excluded area are based on Hertzian, Derjaguin-Muller-Toporov (DMT), and Johnson-Kendall-Roberts (JKR) contact models. Overall, the theoretical models correlated the network specific surface area to the material properties including density, surface tension, Young's modulus, Poisson's ratio, as well as network physical properties, such as density and geometrical characteristics including fiber radius, fiber aspect ratio and network thickness. Pore induction proved to increase the network specific surface area up to 52%, compared to the maximum surface area that could be achieved by nonporous fiber network with the same physical properties and geometrical characteristics. The model based on Johnson-Kendall-Roberts contact model describes accurately the fiber-to-fiber contact area under the experimental conditions used for pore generation. The experimental results and the theoretical model based on Johnson-Kendall-Roberts contact model show that the increase in network surface area due to pore induction can reach to up to 58%.
Theoretical and experimental study of a thruster discharging a weight
NASA Astrophysics Data System (ADS)
Michaels, Dan; Gany, Alon
2014-06-01
An innovative concept for a rocket type thruster that can be beneficial for spacecraft trajectory corrections and station keeping was investigated both experimentally and theoretically. It may also be useful for divert and attitude control systems (DACS). The thruster is based on a combustion chamber discharging a weight through an exhaust tube. Calculations with granular double-base propellant and a solid ejected weight reveal that a specific impulse based on the propellant mass of well above 400 s can be obtained. An experimental thruster was built in order to demonstrate the new idea and validate the model. The thruster impulse was measured both directly with a load cell and indirectly by using a pressure transducer and high speed photography of the weight as it exits the tube, with both ways producing very similar total impulse measurement. The good correspondence between the computations and the measured data validates the model as a useful tool for studying and designing such a thruster.
NASA Astrophysics Data System (ADS)
Xu, Yang; Song, Kai; Shi, Qiang
2018-03-01
The hydride transfer reaction catalyzed by dihydrofolate reductase is studied using a recently developed mixed quantum-classical method to investigate the nuclear quantum effects on the reaction. Molecular dynamics simulation is first performed based on a two-state empirical valence bond potential to map the atomistic model to an effective double-well potential coupled to a harmonic bath. In the mixed quantum-classical simulation, the hydride degree of freedom is quantized, and the effective harmonic oscillator modes are treated classically. It is shown that the hydride transfer reaction rate using the mapped effective double-well/harmonic-bath model is dominated by the contribution from the ground vibrational state. Further comparison with the adiabatic reaction rate constant based on the Kramers theory confirms that the reaction is primarily vibrationally adiabatic, which agrees well with the high transmission coefficients found in previous theoretical studies. The calculated kinetic isotope effect is also consistent with the experimental and recent theoretical results.
NASA Astrophysics Data System (ADS)
Nammi, Srinagalakshmi; Vasa, Nilesh J.; Gurusamy, Balaganesan; Mathur, Anil C.
2017-09-01
A plasma shielding phenomenon and its influence on micromachining is studied experimentally and theoretically for laser wavelengths of 355 nm, 532 nm and 1064 nm. A time resolved pump-probe technique is proposed and demonstrated by splitting a single nanosecond Nd3+:YAG laser into an ablation laser (pump laser) and a probe laser to understand the influence of plasma shielding on laser ablation of copper (Cu) clad on polyimide thin films. The proposed nanosecond pump-probe technique allows simultaneous measurement of the absorption characteristics of plasma produced during Cu film ablation by the pump laser. Experimental measurements of the probe intensity distinctly show that the absorption by the ablated plume increases with increase in the pump intensity, as a result of plasma shielding. Theoretical estimation of the intensity of the transmitted pump beam based on the thermo-temporal modeling is in qualitative agreement with the pump-probe based experimental measurements. The theoretical estimate of the depth attained for a single pulse with high pump intensity value on a Cu thin film is limited by the plasma shielding of the incident laser beam, similar to that observed experimentally. Further, the depth of micro-channels produced shows a similar trend for all three wavelengths, however, the channel depth achieved is lesser at the wavelength of 1064 nm.
The personnel economics approach to public workforce research.
Gibbs, Michael
2009-11-01
This article argues that the relatively new field of personnel economics (PE) holds strong potential as a tool for studying public sector workforces. This subfield of labor economics is based on a strong foundation of microeconomics, which provides a robust theoretical foundation for studying workforce and organizational design issues. PE has evolved on this foundation to a strong practical emphasis, with theoretical insights designed for practical use and with strong focus on empirical research. The field is also characterized by creative data entrepreneurship. The types of datasets that personnel economists use are described. If similar datasets can be obtained for public sector workforces, PE should be a very useful approach for studying them.
Perceived Attributes Predict Course Management System Adopter Status
ERIC Educational Resources Information Center
Keesee, Gayla S.; Shepard, MaryFriend
2011-01-01
This quantitative, nonexperimental study utilized Rogers's diffusion of innovation theory as the theoretical base to determine instructors' perceptions of the attributes (relative advantage, compatibility, complexity, trialability, observability) of the course management system used in order to predict adopter status. The study used a convenience…
NASA Astrophysics Data System (ADS)
Xiao, Deli; Zhang, Chan; He, Jia; Zeng, Rong; Chen, Rong; He, Hua
2016-12-01
Simple, accurate and high-throughput pretreatment method would facilitate large-scale studies of trace analysis in complex samples. Magnetic mixed hemimicelles solid-phase extraction has the power to become a key pretreatment method in biological, environmental and clinical research. However, lacking of experimental predictability and unsharpness of extraction mechanism limit the development of this promising method. Herein, this work tries to establish theoretical-based experimental designs for extraction of trace analytes from complex samples using magnetic mixed hemimicelles solid-phase extraction. We selected three categories and six sub-types of compounds for systematic comparative study of extraction mechanism, and comprehensively illustrated the roles of different force (hydrophobic interaction, π-π stacking interactions, hydrogen-bonding interaction, electrostatic interaction) for the first time. What’s more, the application guidelines for supporting materials, surfactants and sample matrix were also summarized. The extraction mechanism and platform established in the study render its future promising for foreseeable and efficient pretreatment under theoretical based experimental design for trace analytes from environmental, biological and clinical samples.
Humans display a reduced set of consistent behavioral phenotypes in dyadic games.
Poncela-Casasnovas, Julia; Gutiérrez-Roig, Mario; Gracia-Lázaro, Carlos; Vicens, Julian; Gómez-Gardeñes, Jesús; Perelló, Josep; Moreno, Yamir; Duch, Jordi; Sánchez, Angel
2016-08-01
Socially relevant situations that involve strategic interactions are widespread among animals and humans alike. To study these situations, theoretical and experimental research has adopted a game theoretical perspective, generating valuable insights about human behavior. However, most of the results reported so far have been obtained from a population perspective and considered one specific conflicting situation at a time. This makes it difficult to extract conclusions about the consistency of individuals' behavior when facing different situations and to define a comprehensive classification of the strategies underlying the observed behaviors. We present the results of a lab-in-the-field experiment in which subjects face four different dyadic games, with the aim of establishing general behavioral rules dictating individuals' actions. By analyzing our data with an unsupervised clustering algorithm, we find that all the subjects conform, with a large degree of consistency, to a limited number of behavioral phenotypes (envious, optimist, pessimist, and trustful), with only a small fraction of undefined subjects. We also discuss the possible connections to existing interpretations based on a priori theoretical approaches. Our findings provide a relevant contribution to the experimental and theoretical efforts toward the identification of basic behavioral phenotypes in a wider set of contexts without aprioristic assumptions regarding the rules or strategies behind actions. From this perspective, our work contributes to a fact-based approach to the study of human behavior in strategic situations, which could be applied to simulating societies, policy-making scenario building, and even a variety of business applications.
The Use of a Corpus in Contrastive Studies.
ERIC Educational Resources Information Center
Filipovic, Rudolf
1973-01-01
Before beginning the Serbocroatian-English Contrastive Project, it was necessary to determine whether to base the analysis on a corpus or on native intuitions. It seemed that the best method would combine the theoretical and the empirical. A translation method based on a corpus of text was adopted. The Brown University "Standard Sample of…
ERIC Educational Resources Information Center
Harper, Nevin J.; Webster, Anthony L.
2017-01-01
Student learning can be enhanced through applied experience of theoretical knowledge. The purpose of this study was to identify and articulate personal and educational impacts experienced by students during a mentally and physically challenging international adventure-based field school. Nineteen students and two faculty members participated in a…
ERIC Educational Resources Information Center
Burrows, Nikita L.; Nowak, Montana K.; Mooring, Suazette R.
2017-01-01
Students can perceive the laboratory environment in a variety of ways that can affect what they take away from the laboratory course. This qualitative study characterizes undergraduate students' perspectives of a project-based Organic Chemistry laboratory using the theoretical framework of phenomenography. Eighteen participants were interviewed in…
Measuring Disorientation Based on the Needleman-Wunsch Algorithm
ERIC Educational Resources Information Center
Güyer, Tolga; Atasoy, Bilal; Somyürek, Sibel
2015-01-01
This study offers a new method to measure navigation disorientation in web based systems which is powerful learning medium for distance and open education. The Needleman-Wunsch algorithm is used to measure disorientation in a more precise manner. The process combines theoretical and applied knowledge from two previously distinct research areas,…
The Theoretical Basis of Experience-Based Career Education.
ERIC Educational Resources Information Center
Jenks, C. Lynn
This study analyzes the extent to which the assumptions and procedures of the Experience-Based Career Education model (EBCE) as developed by the Far West Laboratory (FWL) are supported by empirical data and by recognized scholars in educational theory. The analysis is presented as relevant to the more general problem: the limited availability of…
Productive Learning Practice--A Theoretical Discussion Based on Two Cases
ERIC Educational Resources Information Center
Lillejord, Solvi; Dysthe, Olga
2008-01-01
In this article, we frame "productive learning" in a sociocultural perspective to show how it ties into a cluster of concepts on activity and transformation and illuminates the relation between learning processes and learning products. Based on two case studies, we argue that understanding learning as action entails developing the students'…
Negotiation of Meaning in Synchronous Computer-Mediated Communication in Relation to Task Types
ERIC Educational Resources Information Center
Cho, Hye-jin
2011-01-01
The present study explored how negotiation of meaning occurred in task-based synchronous computer-mediated communication (SCMC) environment among college English learners. Based on the theoretical framework of the interaction hypothesis and negotiation of meaning, four research questions arose: (1) how negotiation of meaning occur in non-native…
Fidelity of Problem Solving in Everyday Practice: Typical Training May Miss the Mark
ERIC Educational Resources Information Center
Ruby, Susan F.; Crosby-Cooper, Tricia; Vanderwood, Michael L.
2011-01-01
With national attention on scaling up the implementation of Response to Intervention, problem solving teams remain one of the central components for development, implementation, and monitoring of school-based interventions. Studies have shown that problem solving teams evidence a sound theoretical base and demonstrated efficacy; however, limited…
Male and Female Perceptions of an iPad-Based Digital Literacy Curriculum
ERIC Educational Resources Information Center
Hilton, Jason; Canciello, Joseph
2015-01-01
This article reports on original research into student perceptions of the implementation of an iPad-based English curriculum within a public secondary education setting. Building upon a theoretical foundation grounded in digital literacy and technology self-efficacy, this study captures the perceptions of male and female students who shed…
Giving Learning a Helping Hand: Finger Tracing of Temperature Graphs on an iPad
ERIC Educational Resources Information Center
Agostinho, Shirley; Tindall-Ford, Sharon; Ginns, Paul; Howard, Steven J.; Leahy, Wayne; Paas, Fred
2015-01-01
Gesturally controlled information and communication technologies, such as tablet devices, are becoming increasingly popular tools for teaching and learning. Based on the theoretical frameworks of cognitive load and embodied cognition, this study investigated the impact of explicit instructions to trace out elements of tablet-based worked examples…
Using a Game Environment to Foster Collaborative Learning: A Design-Based Study
ERIC Educational Resources Information Center
Hamalainen, Raija
2011-01-01
Designing collaborative three-dimensional learning games for vocational learning may be one way to respond to the needs of working life. The theoretical vantage points of collaborative learning for game development and the "design-based research" methodology are described; these have been used to support collaborative learning in the…
Group-Based Hatred in Intractable Conflict in Israel
ERIC Educational Resources Information Center
Halperin, Eran
2008-01-01
Countless theoretical texts have been written regarding the centrality of hatred as a force that motivates intergroup conflicts. However, surprisingly, at present, almost no empirical study has been conducted either on the nature and character of group-based hatred or on its implications for conflicts. Therefore, the goal of the current work has…
Reading Comprehension Is Embodied: Theoretical and Practical Considerations
ERIC Educational Resources Information Center
Sadoski, Mark
2018-01-01
In this review, I advance the embodied cognition movement in cognitive psychology as both a challenge and an invitation for the study of reading comprehension. Embodied cognition challenges theories which assume that mental operations are based in a common, abstract, amodal code of propositions and schemata. Based on growing research in behavioral…
ERIC Educational Resources Information Center
Chen, Chong
2016-01-01
This study examines the international risks faced by multinational enterprises to understand their impact on the evaluation of investment projects. Moreover, it establishes a 'three-dimensional' theoretical framework of risk identification to analyse the composition of international risk indicators of multinational enterprises based on the theory…
Polarimetric scattering behavior of materials at terahertz frequencies
NASA Astrophysics Data System (ADS)
DiGiovanni, David Anthony
Terahertz spectroscopic techniques have long been used to characterize the electromagnetic behavior of materials for use in radar, astronomy, and remote sensing applications. Spectroscopic information is valuable, but additional information about materials is present in the polarization of the scattered radiation. This thesis has investigated the polarimetric scattering behavior of various rough dielectric and metallic materials from 100 GHz to 1.55 THz. Common building materials and terrain, such as sand, gravel, soil, concrete, and roofing shingles, were studied. In order to obtain a better understanding of basic rough surface scattering phenomenology in this region of the spectrum, roughened metal and plastic samples were studied as well. The scattering behavior of these materials was studied as a function of incident angle, roughness, frequency, and polarization. Theoretical scattering models were used to compare measured results to theoretical predictions. Good agreement was observed between scattering measurements and theoretical predictions based on the small perturbation theory for the roughened metal surfaces. However, a substantial disagreement was observed for the rough dielectric surfaces and is discussed.
Pyatak, Elizabeth A.; Carandang, Kristine; Davis, Shain
2016-01-01
This article reports on the development of a manualized occupational therapy intervention for diabetes management. An initial theoretical framework and core content areas for a Stage 1 intervention manual were developed based on an in-depth needs assessment and review of existing literature. After evaluation by a panel of experts and completion of a feasibility study, the intervention was revised into a Stage 2 manual in preparation for a randomized study evaluating the intervention’s efficacy. In developing the initial manual, we delineated core theoretical principles to allow for flexible application and tailoring of the intervention’s content areas. Expert panel feedback and feasibility study results led to changes to the intervention structure and content as we developed the Stage 2 manual. Through describing this process, we illustrate the dynamic evolution of intervention manuals, which undergo revisions due to both theoretical and practical considerations at each stage of the research-to-clinical practice pipeline. PMID:26594741
Simons, Jack
2008-07-24
The experimental and theoretical study of molecular anions has undergone explosive growth over the past 40 years. Advances in techniques used to generate anions in appreciable numbers as well as new ion-storage, ion-optics, and laser spectroscopic tools have been key on the experimental front. Theoretical developments on the electronic structure and molecular dynamics fronts now allow one to achieve higher accuracy and to study electronically metastable states, thus bringing theory in close collaboration with experiment in this field. In this article, many of the experimental and theoretical challenges specific to studying molecular anions are discussed. Results from many research groups on several classes of molecular anions are overviewed, and both literature citations and active (in online html and pdf versions) links to numerous contributing scientists' Web sites are provided. Specific focus is made on the following families of anions: dipole-bound, zwitterion-bound, double-Rydberg, multiply charged, metastable, cluster-based, and biological anions. In discussing each kind of anion, emphasis is placed on the structural, energetic, spectroscopic, and chemical-reactivity characteristics that make these anions novel, interesting, and important.
Experimental and theoretical study of magnetohydrodynamic ship models.
Cébron, David; Viroulet, Sylvain; Vidal, Jérémie; Masson, Jean-Paul; Viroulet, Philippe
2017-01-01
Magnetohydrodynamic (MHD) ships represent a clear demonstration of the Lorentz force in fluids, which explains the number of students practicals or exercises described on the web. However, the related literature is rather specific and no complete comparison between theory and typical small scale experiments is currently available. This work provides, in a self-consistent framework, a detailed presentation of the relevant theoretical equations for small MHD ships and experimental measurements for future benchmarks. Theoretical results of the literature are adapted to these simple battery/magnets powered ships moving on salt water. Comparison between theory and experiments are performed to validate each theoretical step such as the Tafel and the Kohlrausch laws, or the predicted ship speed. A successful agreement is obtained without any adjustable parameter. Finally, based on these results, an optimal design is then deduced from the theory. Therefore this work provides a solid theoretical and experimental ground for small scale MHD ships, by presenting in detail several approximations and how they affect the boat efficiency. Moreover, the theory is general enough to be adapted to other contexts, such as large scale ships or industrial flow measurement techniques.
Experimental and theoretical study of magnetohydrodynamic ship models
Viroulet, Sylvain; Vidal, Jérémie; Masson, Jean-Paul; Viroulet, Philippe
2017-01-01
Magnetohydrodynamic (MHD) ships represent a clear demonstration of the Lorentz force in fluids, which explains the number of students practicals or exercises described on the web. However, the related literature is rather specific and no complete comparison between theory and typical small scale experiments is currently available. This work provides, in a self-consistent framework, a detailed presentation of the relevant theoretical equations for small MHD ships and experimental measurements for future benchmarks. Theoretical results of the literature are adapted to these simple battery/magnets powered ships moving on salt water. Comparison between theory and experiments are performed to validate each theoretical step such as the Tafel and the Kohlrausch laws, or the predicted ship speed. A successful agreement is obtained without any adjustable parameter. Finally, based on these results, an optimal design is then deduced from the theory. Therefore this work provides a solid theoretical and experimental ground for small scale MHD ships, by presenting in detail several approximations and how they affect the boat efficiency. Moreover, the theory is general enough to be adapted to other contexts, such as large scale ships or industrial flow measurement techniques. PMID:28665941
NASA Astrophysics Data System (ADS)
Saleh, K.; Bouchier, A.; Merrer, P. H.; Llopis, O.; Cibiel, G.
2011-03-01
In the microwave domain and among many other advantages, optics represents an elegant solution to increase the quality Q factor in a system. Different types of optical resonators lead to Q factors above 109, and these resonators can be used as an alternative to optical delay lines to set up the frequency in optoelectronic oscillators (OEO). However, microwave-optics is also a complex field, and if the use of optical resonators in high spectral purity frequency generation systems like OEO has been already demonstrated, many aspects of these OEOs are still incompletely understood, especially the contribution to the oscillator phase noise of the different optical and microwave elements used in the oscillator system. In order to improve the phase noise of a fiber ring resonator based OEO, this oscillator has been theoretically studied in term of white frequency noise. In this paper, we present a theoretical study that has lead us to optimize a fiber ring resonator and the experimental phase noise results obtained for an OEO based on an optimized optical resonator. The OEO thermal stability is also investigated in this paper.
Wohlers, Christina; Hertel, Guido
2017-04-01
Although there is a trend in today's organisations to implement activity-based flexible offices (A-FOs), only a few studies examine consequences of this new office type. Moreover, the underlying mechanisms why A-FOs might lead to different consequences as compared to cellular and open-plan offices are still unclear. This paper introduces a theoretical framework explaining benefits and risks of A-FOs based on theories from work and organisational psychology. After deriving working conditions specific for A-FOs (territoriality, autonomy, privacy, proximity and visibility), differences in working conditions between A-FOs and alternative office types are proposed. Further, we suggest how these differences in working conditions might affect work-related consequences such as well-being, satisfaction, motivation and performance on the individual, the team and the organisational level. Finally, we consider task-related (e.g. task variety), person-related (e.g. personality) and organisational (e.g. leadership) moderators. Based on this model, future research directions as well as practical implications are discussed. Practitioner Summary: Activity-based flexible offices (A-FOs) are popular in today's organisations. This article presents a theoretical model explaining why and when working in an A-FO evokes benefits and risks for individuals, teams and organisations. According to the model, A-FOs are beneficial when management encourages employees to use the environment appropriately and supports teams.
Conceptualizing, Designing, and Investigating Locative Media Use in Urban Space
NASA Astrophysics Data System (ADS)
Diamantaki, Katerina; Rizopoulos, Charalampos; Charitos, Dimitris; Kaimakamis, Nikos
This chapter investigates the social implications of locative media (LM) use and attempts to outline a theoretical framework that may support the design and implementation of location-based applications. Furthermore, it stresses the significance of physical space and location awareness as important factors that influence both human-computer interaction and computer-mediated communication. The chapter documents part of the theoretical aspect of the research undertaken as part of LOcation-based Communication Urban NETwork (LOCUNET), a project that aims to investigate the way users interact with one another (human-computer-human interaction aspect) and with the location-based system itself (human-computer interaction aspect). A number of relevant theoretical approaches are discussed in an attempt to provide a holistic theoretical background for LM use. Additionally, the actual implementation of the LOCUNET system is described and some of the findings are discussed.
Diagnosing and dealing with multicollinearity.
Schroeder, M A
1990-04-01
The purpose of this article was to increase nurse researchers' awareness of the effects of collinear data in developing theoretical models for nursing practice. Collinear data distort the true value of the estimates generated from ordinary least-squares analysis. Theoretical models developed to provide the underpinnings of nursing practice need not be abandoned, however, because they fail to produce consistent estimates over repeated applications. It is also important to realize that multicollinearity is a data problem, not a problem associated with misspecification of a theorectical model. An investigator must first be aware of the problem, and then it is possible to develop an educated solution based on the degree of multicollinearity, theoretical considerations, and sources of error associated with alternative, biased, least-square regression techniques. Decisions based on theoretical and statistical considerations will further the development of theory-based nursing practice.
Farmer, Richard F; Seeley, John R; Kosty, Derek B; Lewinsohn, Peter M
2009-11-01
Research on hierarchical modeling of psychopathology has frequently identified 2 higher order latent factors, internalizing and externalizing. When based on the comorbidity of psychiatric diagnoses, the externalizing domain has usually been modeled as a single latent factor. Multivariate studies of externalizing symptom features, however, suggest multidimensionality. To address this apparent contradiction, confirmatory factor analytic methods and information-theoretic criteria were used to evaluate 4 theoretically plausible measurement models based on lifetime comorbidity patterns of 7 putative externalizing disorders. Diagnostic information was collected at 4 assessment waves from an age-based cohort of 816 persons between the ages of 14 and 33. A 2-factor model that distinguished oppositional behavior disorders (attention-deficit/hyperactivity disorder, oppositional defiant disorder) from social norm violation disorders (conduct disorder, adult antisocial behavior, alcohol use disorder, cannabis use disorder, hard drug use disorder) demonstrated consistently good fit and superior approximating abilities. Analyses of psychosocial outcomes measured at the last assessment wave supported the validity of this 2-factor model. Implications of this research for the theoretical understanding of domain-related disorders and the organization of classification systems are discussed. PsycINFO Database Record 2009 APA, all rights reserved.
ERIC Educational Resources Information Center
Raudla, Ringa; Karo, Erkki; Valdmaa, Kaija; Kattel, Rainer
2015-01-01
The main goal of the paper is to explore--both theoretically and empirically--the implications of project-based research funding for budgeting and financial management at public universities. The theoretical contribution of the paper is to provide a synthesized discussion of the possible impacts of project-based funding on university financial…
Testing a Theoretical Model of Immigration Transition and Physical Activity.
Chang, Sun Ju; Im, Eun-Ok
2015-01-01
The purposes of the study were to develop a theoretical model to explain the relationships between immigration transition and midlife women's physical activity and test the relationships among the major variables of the model. A theoretical model, which was developed based on transitions theory and the midlife women's attitudes toward physical activity theory, consists of 4 major variables, including length of stay in the United States, country of birth, level of acculturation, and midlife women's physical activity. To test the theoretical model, a secondary analysis with data from 127 Hispanic women and 123 non-Hispanic (NH) Asian women in a national Internet study was used. Among the major variables of the model, length of stay in the United States was negatively associated with physical activity in Hispanic women. Level of acculturation in NH Asian women was positively correlated with women's physical activity. Country of birth and level of acculturation were significant factors that influenced physical activity in both Hispanic and NH Asian women. The findings support the theoretical model that was developed to examine relationships between immigration transition and physical activity; it shows that immigration transition can play an essential role in influencing health behaviors of immigrant populations in the United States. The NH theoretical model can be widely used in nursing practice and research that focus on immigrant women and their health behaviors. Health care providers need to consider the influences of immigration transition to promote immigrant women's physical activity.
Theoretical study on the sound absorption of electrolytic solutions. II. Assignments of relaxations.
Yamaguchi, T; Matsuoka, T; Koda, S
2007-08-14
The theory on the ultrasonic absorption spectrum of electrolytic solutions recently proposed by us is applied to the model system that resembles to the aqueous solution of MgSO4. The charges on ions are reduced to +/-1.5e in order to obtain the equilibrium structure by the integral equation theory. The theory reproduces the existence of two relaxations around 100 kHz and 1 GHz. The physical origin of the relaxation is analyzed based on the theoretical expression. The slower relaxation is shown to originate in the formation of contact ion pair, in harmony with the conventional assignment. The amplitude of this relaxation agrees with the experimental one fairly well. The absorption cross section is a weakly increasing function of the concentration of the salt in theory, whereas it depends little on the concentration in experiment, which is ascribed to the weaker association of the pair in the theory. The deviation from the Debye relaxation is found for the faster process, and the concentration dependence is small. The analysis shows that this relaxation stems from the coupling between the pressure and the long-range concentration fluctuation, and the concentration independence and the non-Debye relaxation are explained based on the theoretical analysis. In particular, the theory demonstrates that this process has the t(-3/2) tail in the time domain, which is confirmed by numerical calculation. The deviation of the theoretical relaxation amplitude from the experimental one is elucidated in terms of the theoretical expression of the coefficient.
Optical properties of B12P2 crystals: Ab initio calculation and EELS
NASA Astrophysics Data System (ADS)
Reshetniak, V. V.; Mavrin, B. N.; Medvedev, V. V.; Perezhogin, I. A.; Kulnitskiy, B. A.
2018-05-01
We report an experimental and theoretical investigation of the electronic structure and optical properties of B12P2 crystals in the energy range up to 60 eV. Experimental studies are performed by the method of electron energy loss spectroscopy, and theoretical studies are carried out using density functional theory and the GW approximation. The calculated dependence of the energy loss function is in agreement with the experiment. Based on the results of the calculations, we determine the optical properties of B12P2 crystals and investigate their anisotropy. The dispersion and density of electronic states are calculated and analyzed.
Perinatal Bereavement: A Principle-based Concept Analysis
FENSTERMACHER, Kimberly; HUPCEY, Judith E.
2013-01-01
Aim This paper is a report of an analysis of the concept of perinatal bereavement. Background The concept of perinatal bereavement emerged in the scientific literature during the 1970s. Perinatal bereavement is a practice based concept, although it is not well defined in the scientific literature and is often intermingled with the concepts of mourning and grief. Design Concept Analysis. Data Sources Using the term ‘perinatal bereavement’ and limits of only English and human, Pub Med and CINAHL were searched to yield 278 available references dating from 1974 – 2011. Articles specific to the experience of perinatal bereavement were reviewed. The final data set was 143 articles. Review Methods The methods of principle-based concept analysis were used. Results reveal conceptual components (antecedents, attributes and outcomes) which are delineated to create a theoretical definition of perinatal bereavement. Results The concept is epistemologically immature, with few explicit definitions to describe the phenomenon. Inconsistency in conceptual meaning threatens the construct validity of measurement tools for perinatal bereavement and contributes to incongruent theoretical definitions. This has implications for both nursing science (how the concept is studied and theoretically integrated) and clinical practice (timing and delivery of support interventions). Conclusions Perinatal bereavement is a multifaceted global phenomenon that follows perinatal loss. Lack of conceptual clarity and lack of a clearly articulated conceptual definition impede the synthesis and translation of research findings into practice. A theoretical definition of perinatal bereavement is offered as a platform for researchers to advance the concept through research and theory development. PMID:23458030
Seward, Kirsty; Wolfenden, Luke; Wiggers, John; Finch, Meghan; Wyse, Rebecca; Oldmeadow, Christopher; Presseau, Justin; Clinton-McHarg, Tara; Yoong, Sze Lin
2017-04-04
While there are number of frameworks which focus on supporting the implementation of evidence based approaches, few psychometrically valid measures exist to assess constructs within these frameworks. This study aimed to develop and psychometrically assess a scale measuring each domain of the Theoretical Domains Framework for use in assessing the implementation of dietary guidelines within a non-health care setting (childcare services). A 75 item 14-domain Theoretical Domains Framework Questionnaire (TDFQ) was developed and administered via telephone interview to 202 centre based childcare service cooks who had a role in planning the service menu. Confirmatory factor analysis (CFA) was undertaken to assess the reliability, discriminant validity and goodness of fit of the 14-domain theoretical domain framework measure. For the CFA, five iterative processes of adjustment were undertaken where 14 items were removed, resulting in a final measure consisting of 14 domains and 61 items. For the final measure: the Chi-Square goodness of fit statistic was 3447.19; the Standardized Root Mean Square Residual (SRMR) was 0.070; the Root Mean Square Error of Approximation (RMSEA) was 0.072; and the Comparative Fit Index (CFI) had a value of 0.78. While only one of the three indices support goodness of fit of the measurement model tested, a 14-domain model with 61 items showed good discriminant validity and internally consistent items. Future research should aim to assess the psychometric properties of the developed TDFQ in other community-based settings.
Meta-analysis on the effectiveness of team-based learning on medical education in China.
Chen, Minjian; Ni, Chunhui; Hu, Yanhui; Wang, Meilin; Liu, Lu; Ji, Xiaoming; Chu, Haiyan; Wu, Wei; Lu, Chuncheng; Wang, Shouyu; Wang, Shoulin; Zhao, Liping; Li, Zhong; Zhu, Huijuan; Wang, Jianming; Xia, Yankai; Wang, Xinru
2018-04-10
Team-based learning (TBL) has been adopted as a new medical pedagogical approach in China. However, there are no studies or reviews summarizing the effectiveness of TBL on medical education. This study aims to obtain an overall estimation of the effectiveness of TBL on outcomes of theoretical teaching of medical education in China. We retrieved the studies from inception through December, 2015. Chinese National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chinese Wanfang Database, Chinese Scientific Journal Database, PubMed, EMBASE and Cochrane Database were searched. The quality of included studies was assessed by the Newcastle-Ottawa scale. Standardized mean difference (SMD) was applied for the estimation of the pooled effects. Heterogeneity assumption was detected by I 2 statistics, and was further explored by meta-regression analysis. A total of 13 articles including 1545 participants eventually entered into the meta-analysis. The quality scores of these studies ranged from 6 to 10. Altogether, TBL significantly increased students' theoretical examination scores when compared with lecture-based learning (LBL) (SMD = 2.46, 95% CI: 1.53-3.40). Additionally, TBL significantly increased students' learning attitude (SMD = 3.23, 95% CI: 2.27-4.20), and learning skill (SMD = 2.70, 95% CI: 1.33-4.07). The meta-regression results showed that randomization, education classification and gender diversity were the factors that caused heterogeneity. TBL in theoretical teaching of medical education seems to be more effective than LBL in improving the knowledge, attitude and skill of students in China, providing evidence for the implement of TBL in medical education in China. The medical schools should implement TBL with the consideration on the practical teaching situations such as students' education level.
One-dimensional barcode reading: an information theoretic approach
NASA Astrophysics Data System (ADS)
Houni, Karim; Sawaya, Wadih; Delignon, Yves
2008-03-01
In the convergence context of identification technology and information-data transmission, the barcode found its place as the simplest and the most pervasive solution for new uses, especially within mobile commerce, bringing youth to this long-lived technology. From a communication theory point of view, a barcode is a singular coding based on a graphical representation of the information to be transmitted. We present an information theoretic approach for 1D image-based barcode reading analysis. With a barcode facing the camera, distortions and acquisition are modeled as a communication channel. The performance of the system is evaluated by means of the average mutual information quantity. On the basis of this theoretical criterion for a reliable transmission, we introduce two new measures: the theoretical depth of field and the theoretical resolution. Simulations illustrate the gain of this approach.
One-dimensional barcode reading: an information theoretic approach.
Houni, Karim; Sawaya, Wadih; Delignon, Yves
2008-03-10
In the convergence context of identification technology and information-data transmission, the barcode found its place as the simplest and the most pervasive solution for new uses, especially within mobile commerce, bringing youth to this long-lived technology. From a communication theory point of view, a barcode is a singular coding based on a graphical representation of the information to be transmitted. We present an information theoretic approach for 1D image-based barcode reading analysis. With a barcode facing the camera, distortions and acquisition are modeled as a communication channel. The performance of the system is evaluated by means of the average mutual information quantity. On the basis of this theoretical criterion for a reliable transmission, we introduce two new measures: the theoretical depth of field and the theoretical resolution. Simulations illustrate the gain of this approach.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andronov, V.A.; Zhidov, I.G.; Meskov, E.E.
The report presents the basic results of some calculations, theoretical and experimental efforts in the study of Rayleigh-Taylor, Kelvin-Helmholtz, Richtmyer-Meshkov instabilities and the turbulent mixing which is caused by their evolution. Since the late forties the VNIIEF has been conducting these investigations. This report is based on the data which were published in different times in Russian and foreign journals. The first part of the report deals with calculations an theoretical techniques for the description of hydrodynamic instabilities applied currently, as well as with the results of several individual problems and their comparison with the experiment. These methods can bemore » divided into two types: direct numerical simulation methods and phenomenological methods. The first type includes the regular 2D and 3D gasdynamical techniques as well as the techniques based on small perturbation approximation and on incompressible liquid approximation. The second type comprises the techniques based on various phenomenological turbulence models. The second part of the report describes the experimental methods and cites the experimental results of Rayleigh-Taylor and Richtmyer-Meskov instability studies as well as of turbulent mixing. The applied methods were based on thin-film gaseous models, on jelly models and liquid layer models. The research was done for plane and cylindrical geometries. As drivers, the shock tubes of different designs were used as well as gaseous explosive mixtures, compressed air and electric wire explosions. The experimental results were applied in calculational-theoretical technique calibrations. The authors did not aim at covering all VNIIEF research done in this field of science. To a great extent the choice of the material depended on the personal contribution of the author in these studies.« less
Acuity of a Cryptochrome and Vision-Based Magnetoreception System in Birds
Solov'yov, Ilia A.; Mouritsen, Henrik; Schulten, Klaus
2010-01-01
Abstract The magnetic compass of birds is embedded in the visual system and it has been hypothesized that the primary sensory mechanism is based on a radical pair reaction. Previous models of magnetoreception have assumed that the radical pair-forming molecules are rigidly fixed in space, and this assumption has been a major objection to the suggested hypothesis. In this article, we investigate theoretically how much disorder is permitted for the radical pair-forming, protein-based magnetic compass in the eye to remain functional. Our study shows that only one rotational degree of freedom of the radical pair-forming protein needs to be partially constrained, while the other two rotational degrees of freedom do not impact the magnetoreceptive properties of the protein. The result implies that any membrane-associated protein is sufficiently restricted in its motion to function as a radical pair-based magnetoreceptor. We relate our theoretical findings to the cryptochromes, currently considered the likeliest candidate to furnish radical pair-based magnetoreception. PMID:20655831
Promoting mental wellbeing: developing a theoretically and empirically sound complex intervention.
Millar, S L; Donnelly, M
2014-06-01
This paper describes the development of a complex intervention to promote mental wellbeing using the revised framework for developing and evaluating complex interventions produced by the UK Medical Research Council (UKMRC). Application of the first two phases of the framework is described--development and feasibility and piloting. The theoretical case and evidence base were examined analytically to explicate the theoretical and empirical foundations of the intervention. These findings informed the design of a 12-week mental wellbeing promotion programme providing early intervention for people showing signs of mental health difficulties. The programme is based on the theoretical constructs of self-efficacy, self-esteem, purpose in life, resilience and social support and comprises 10 steps. A mixed methods approach was used to conduct a feasibility study with community and voluntary sector service users and in primary care. A significant increase in mental wellbeing was observed following participation in the intervention. Qualitative data corroborated this finding and suggested that the intervention was feasible to deliver and acceptable to participants, facilitators and health professionals. The revised UKMRC framework can be successfully applied to the development of public health interventions. © The Author 2013. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Supervision of Facilitators in a Multisite Study: Goals, Process, and Outcomes
2010-01-01
Objective To describe the aims, implementation, and desired outcomes of facilitator supervision for both interventions (treatment and control) in Project Eban and to present the Eban Theoretical Framework for Supervision that guided the facilitators’ supervision. The qualifications and training of supervisors and facilitators are also described. Design This article provides a detailed description of supervision in a multisite behavioral intervention trial. The Eban Theoretical Framework for Supervision is guided by 3 theories: cognitive behavior therapy, the Life-long Model of Supervision, and “Empowering supervisees to empower others: a culturally responsive supervision model.” Methods Supervision is based on the Eban Theoretical Framework for Supervision, which provides guidelines for implementing both interventions using goals, process, and outcomes. Results Because of effective supervision, the interventions were implemented with fidelity to the protocol and were standard across the multiple sites. Conclusions Supervision of facilitators is a crucial aspect of multisite intervention research quality assurance. It provides them with expert advice, optimizes the effectiveness of facilitators, and increases adherence to the protocol across multiple sites. Based on the experience in this trial, some of the challenges that arise when conducting a multisite randomized control trial and how they can be handled by implementing the Eban Theoretical Framework for Supervision are described. PMID:18724192
An experimental and theoretical analysis of a foil-air bearing rotor system
NASA Astrophysics Data System (ADS)
Bonello, P.; Hassan, M. F. Bin
2018-01-01
Although there is considerable research on the experimental testing of foil-air bearing (FAB) rotor systems, only a small fraction has been correlated with simulations from a full nonlinear model that links the rotor, air film and foil domains, due to modelling complexity and computational burden. An approach for the simultaneous solution of the three domains as a coupled dynamical system, introduced by the first author and adopted by independent researchers, has recently demonstrated its capability to address this problem. This paper uses this approach, with further developments, in an experimental and theoretical study of a FAB-rotor test rig. The test rig is described in detail, including issues with its commissioning. The theoretical analysis uses a recently introduced modal-based bump foil model that accounts for interaction between the bumps and their inertia. The imposition of pressure constraints on the air film is found to delay the predicted onset of instability speed. The results lend experimental validation to a recent theoretically-based claim that the Gümbel condition may not be appropriate for a practical single-pad FAB. The satisfactory prediction of the salient features of the measured nonlinear behavior shows that the air film is indeed highly influential on the response, in contrast to an earlier finding.
NASA Astrophysics Data System (ADS)
Liu, Lei; Zhang, Chi; Luo, Meng; Chen, Xi; Li, Dichen; Chen, Hualing
2017-08-01
Dielectric elastomers (DEs) have great potential for use as artificial muscles because of the following characteristics: electrical activity, fast and large deformation under stimuli, and softness as natural muscles. Inspired by the traditional McKibben actuators, in this study, we developed a cylindrical soft fiber-reinforced and electropneumatic DE artificial muscle (DEAM) by mimicking the spindle shape of natural muscles. Based on continuum mechanics and variation principle, the inhomogeneous actuation of DEAMs was theoretically modeled and calculated. Prototypes of DEAMs were prepared to validate the design concept and theoretical model. The theoretical predictions are consistent with the experimental results; they successfully predicted the evolutions of the contours of DEAMs with voltage. A pneumatically supported high prestretch in the hoop direction was achieved by our DEAM prototype without buckling the soft fibers sandwiched by the DE films. Besides, a continuously tunable prestretch in the actuation direction was achieved by varying the supporting pressure. Using the theoretical model, the failure modes, maximum actuations, and critical voltages were analyzed; they were highly dependent on the structural parameters, i.e., the cylinder aspect ratio, prestretch level, and supporting pressure. The effects of structural parameters and supporting pressure on the actuation performance were also investigated to optimize the DEAMs.
ERIC Educational Resources Information Center
Arslan Buyruk, Arzu; Ogan Bekiroglu, Feral
2018-01-01
The focus of this study was to evaluate the impact of model-based inquiry on pre-service physics teachers' conceptual understanding of dynamics. Theoretical framework of this research was based on models-of-data theory. True-experimental design using quantitative and qualitative research methods was carried out for this research. Participants of…
Generational Differences in Technology Adoption in Community Colleges
ERIC Educational Resources Information Center
Rosario, Victoria C.
2012-01-01
This research study investigated the technological perceptions and expectations of community college students, faculty, administrators, and Information Technology (IT) staff. The theoretical framework is based upon two assumptions on the process of technological innovation: it can be explained by diffusion of adoption theory, and by studying the…
Very high power THz radiation sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carr, G.L.; Martin, Michael C.; McKinney, Wayne R.
2002-10-31
We report the production of high power (20 watts average, {approx} 1 Megawatt peak) broadband THz light based on coherent emission from relativistic electrons. Such sources are ideal for imaging, for high power damage studies and for studies of non-linear phenomena in this spectral range. We describe the source, presenting theoretical calculations and their experimental verification. For clarity we compare this source to one based on ultrafast laser techniques.
Montgomery, James W; Gillam, Ronald B; Evans, Julia L
2016-12-01
Compared with same-age typically developing peers, school-age children with specific language impairment (SLI) exhibit significant deficits in spoken sentence comprehension. They also demonstrate a range of memory limitations. Whether these 2 deficit areas are related is unclear. The present review article aims to (a) review 2 main theoretical accounts of SLI sentence comprehension and various studies supporting each and (b) offer a new, broader, more integrated memory-based framework to guide future SLI research, as we believe the available evidence favors a memory-based perspective of SLI comprehension limitations. We reviewed the literature on the sentence comprehension abilities of English-speaking children with SLI from 2 theoretical perspectives. The sentence comprehension limitations of children with SLI appear to be more fully captured by a memory-based perspective than by a syntax-specific deficit perspective. Although a memory-based view appears to be the better account of SLI sentence comprehension deficits, this view requires refinement and expansion. Current memory-based perspectives of adult sentence comprehension, with proper modification, offer SLI investigators new, more integrated memory frameworks within which to study and better understand the sentence comprehension abilities of children with SLI.
Gillam, Ronald B.; Evans, Julia L.
2016-01-01
Purpose Compared with same-age typically developing peers, school-age children with specific language impairment (SLI) exhibit significant deficits in spoken sentence comprehension. They also demonstrate a range of memory limitations. Whether these 2 deficit areas are related is unclear. The present review article aims to (a) review 2 main theoretical accounts of SLI sentence comprehension and various studies supporting each and (b) offer a new, broader, more integrated memory-based framework to guide future SLI research, as we believe the available evidence favors a memory-based perspective of SLI comprehension limitations. Method We reviewed the literature on the sentence comprehension abilities of English-speaking children with SLI from 2 theoretical perspectives. Results The sentence comprehension limitations of children with SLI appear to be more fully captured by a memory-based perspective than by a syntax-specific deficit perspective. Conclusions Although a memory-based view appears to be the better account of SLI sentence comprehension deficits, this view requires refinement and expansion. Current memory-based perspectives of adult sentence comprehension, with proper modification, offer SLI investigators new, more integrated memory frameworks within which to study and better understand the sentence comprehension abilities of children with SLI. PMID:27973643
Yemets, Anatoliy V; Donchenko, Viktoriya I; Scrinick, Eugenia O
2018-01-01
Introduction: Experimental work is aimed at introducing theoretical and methodological foundations for the professional training of the future doctor. The aim: Identify the dynamics of quantitative and qualitative indicators of the readiness of a specialist in medicine. Materials and methods: The article presents the course and results of the experimental work of the conditions of forming the readiness of future specialists in medicine. Results: Our methodical bases for studying the disciplines of the general practice and specialized professional stage of experimental training of future physicians have been worked out. Conclusions: It is developed taking into account the peculiarities of future physician training of materials for various stages of experimental implementation in the educational process of higher medical educational institutions.
Assessment of credit risk based on fuzzy relations
NASA Astrophysics Data System (ADS)
Tsabadze, Teimuraz
2017-06-01
The purpose of this paper is to develop a new approach for an assessment of the credit risk to corporate borrowers. There are different models for borrowers' risk assessment. These models are divided into two groups: statistical and theoretical. When assessing the credit risk for corporate borrowers, statistical model is unacceptable due to the lack of sufficiently large history of defaults. At the same time, we cannot use some theoretical models due to the lack of stock exchange. In those cases, when studying a particular borrower given that statistical base does not exist, the decision-making process is always of expert nature. The paper describes a new approach that may be used in group decision-making. An example of the application of the proposed approach is given.
A Study of Wind Turbine Comprehensive Operational Assessment Model Based on EM-PCA Algorithm
NASA Astrophysics Data System (ADS)
Zhou, Minqiang; Xu, Bin; Zhan, Yangyan; Ren, Danyuan; Liu, Dexing
2018-01-01
To assess wind turbine performance accurately and provide theoretical basis for wind farm management, a hybrid assessment model based on Entropy Method and Principle Component Analysis (EM-PCA) was established, which took most factors of operational performance into consideration and reach to a comprehensive result. To verify the model, six wind turbines were chosen as the research objects, the ranking obtained by the method proposed in the paper were 4#>6#>1#>5#>2#>3#, which are completely in conformity with the theoretical ranking, which indicates that the reliability and effectiveness of the EM-PCA method are high. The method could give guidance for processing unit state comparison among different units and launching wind farm operational assessment.
NASA Astrophysics Data System (ADS)
Szekrényes, Zsolt; Nagy, Péter R.; Tarczay, György; Maggini, Laura; Bonifazi, Davide; Kamarás, Katalin
2018-01-01
Three types of supramolecular interactions are identified in the three crystallographic directions in crystals of 1,4-bis[(1-hexylurac-6-yl) ethynyl]benzene, a uracil-based molecule with a linear backbone. These three interactions, characterized by their strongest component, are: intermolecular double H-bonds along the molecular axis, London dispersion interaction of hexyl chains connecting these linear assemblies, and π - π stacking of the aromatic rings perpendicular to the molecular planes. On heating, two transitions happen, disordering of hexyl chains at 473 K, followed by H-bond melting at 534 K. The nature of the bonds and transitions was established by matrix-isolation and temperature-dependent infrared spectroscopy and supported by theoretical computations.
NASA Astrophysics Data System (ADS)
Prasai, Binay; Wilson, A. R.; Wiley, B. J.; Ren, Y.; Petkov, Valeri
2015-10-01
The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design. Electronic supplementary information (ESI) available: XRD patterns, TEM and 3D structure modelling methodology. See DOI: 10.1039/c5nr04678e
Classifying Correlation Matrices into Relatively Homogeneous Subgroups: A Cluster Analytic Approach
ERIC Educational Resources Information Center
Cheung, Mike W.-L.; Chan, Wai
2005-01-01
Researchers are becoming interested in combining meta-analytic techniques and structural equation modeling to test theoretical models from a pool of studies. Most existing procedures are based on the assumption that all correlation matrices are homogeneous. Few studies have addressed what the next step should be when studies being analyzed are…
NASA Astrophysics Data System (ADS)
Fahid, Farzaneh; Kanaani, Ayoub; Pourmousavi, Seied Ali; Ajloo, Davood
2017-04-01
The (Z)-4-(phenylamino) pent-3-en-2-one (PAPO) was synthesised applying carbon-based solid acid and described by experimental techniques. Calculated results reveal that its keto-amine form is more stable than its enol-imine form. A relaxed potential energy surface scan has been accomplished based on the optimised geometry of NH tautomeric form to depict the potential energy barrier related to intramolecular proton transfer. The spectroscopic results and theoretical calculations demonstrate that the intramolecular hydrogen bonding strength of PAPO is stronger than that in 4-amino-3-penten-2-one)APO(. In addition, molecular electrostatic potential, total and partial density of stats (TDOS, PDOS) and non-linear optical properties of the compound were studied using same theoretical calculations. Our calculations show that the title molecule has the potential to be used as molecular switch.
Stereotype Threat and College Academic Performance: A Latent Variables Approach*
Owens, Jayanti; Massey, Douglas S.
2013-01-01
Stereotype threat theory has gained experimental and survey-based support in helping explain the academic underperformance of minority students at selective colleges and universities. Stereotype threat theory states that minority students underperform because of pressures created by negative stereotypes about their racial group. Past survey-based studies, however, are characterized by methodological inefficiencies and potential biases: key theoretical constructs have only been measured using summed indicators and predicted relationships modeled using ordinary least squares. Using the National Longitudinal Survey of Freshman, this study overcomes previous methodological shortcomings by developing a latent construct model of stereotype threat. Theoretical constructs and equations are estimated simultaneously from multiple indicators, yielding a more reliable, valid, and parsimonious test of key propositions. Findings additionally support the view that social stigma can indeed have strong negative effects on the academic performance of pejoratively stereotyped racial-minority group members, not only in laboratory settings, but also in the real world. PMID:23950616
Insight into the C-F bond mechanism of molecular analogs for antibacterial drug design.
Liu, Junna; Lv, Biyu; Liu, Huaqing; Li, Xin; Yin, Weiping
2018-06-01
The activities of biological molecules usually rely on both of intra-molecular and intermolecular interactions between their function groups. These interactions include interonic attraction theory, Van der Waal's forces and the function of geometry on the individual molecules, whether they are naturally or synthetic. The purpose of this study was to evaluate the antibacterial activity of C-F bond compound using combination of experiments verification and theoretical calculation. We target on the insect natural products from the maggots of Chrysomyis megacephala Fabricius. Based on density functional theory(DFT) and B3LYP method, a theoretical study of the C-F bond on fluoride was designed to explore compounds 2 and 4 antibacterial structure-activity relationship. With the progress in DFT, first-principle calculation based on DFT has gradually become a routine method for drug design, quantum chemistry and other science fields.
T. D. Nguyen-Phan; Baber, A. E.; Rodriguez, J. A.; ...
2015-12-10
The use of metal nanoparticles (NPs), including Au and Pt, supported over oxides has been pivotal, and is ever increasing in enabling catalytic reactions which target the production of hydrogen. We review here the most recent works pertaining to the fundamental understanding of the structure, morphology, growth, characterization, and intrinsic phenomenological properties of Au– and Pt– based catalysts that influence the reactivity and selectivity to target hydrogen production. We draw on surface science and theoretical methods of model and powder catalysts using high resolution imaging, spectroscopy, scattering experiments, and theoretical studies. Based on these insights we identify key aspects ofmore » studies of supported metal nanoparticle (NP) catalysts for several reactions. The main focus of this review is on the intersection of catalytic chemistry related to the water-gas shift (WGS), oxygenate steam reforming (OSR), and solarassisted reactions (SAR).« less
NASA Astrophysics Data System (ADS)
Shang, De-Yi; Zhong, Liang-Cai
2017-01-01
Our novel models for fluid's variable physical properties are improved and reported systematically in this work for enhancement of theoretical and practical value on study of convection heat and mass transfer. It consists of three models, namely (1) temperature parameter model, (2) polynomial model, and (3) weighted-sum model, respectively for treatment of temperature-dependent physical properties of gases, temperature-dependent physical properties of liquids, and concentration- and temperature-dependent physical properties of vapour-gas mixture. Two related components are proposed, and involved in each model for fluid's variable physical properties. They are basic physic property equations and theoretical similarity equations on physical property factors. The former, as the foundation of the latter, is based on the typical experimental data and physical analysis. The latter is built up by similarity analysis and mathematical derivation based on the former basic physical properties equations. These models are available for smooth simulation and treatment of fluid's variable physical properties for assurance of theoretical and practical value of study on convection of heat and mass transfer. Especially, so far, there has been lack of available study on heat and mass transfer of film condensation convection of vapour-gas mixture, and the wrong heat transfer results existed in widespread studies on the related research topics, due to ignorance of proper consideration of the concentration- and temperature-dependent physical properties of vapour-gas mixture. For resolving such difficult issues, the present novel physical property models have their special advantages.
Polarization characteristics of an altazimuth sky scanner
NASA Technical Reports Server (NTRS)
Garrison, L. M.; Blaszczak, Z.; Green, A. E. S.
1980-01-01
A theoretical description of the polarization characteristics of an altazimuth sky scanner optical system based on Mueller-Stokes calculus is presented. This computer-driven optical system was designed to perform laboratory studies of skylight and of celestial objects during day or night, and has no space limitations; however, the two parallel 45 deg tilt mirrors introduce some intrinsic polarization. Therefore, proper data interpretation requires a theoretical understanding of the polarization features of the instrument and accurate experimental determination of the Mueller-Stokes matrix elements describing the polarizing and depolarizing action of the system.
Electron Capture in Slow Collision of He^2++H : Revisited
NASA Astrophysics Data System (ADS)
Krstic, Ps
2003-05-01
Very early experimental data (Fite et al. al., Proc. R. Soc. A 268, 527 (1962)) for He^2++H, recent ORNL measurements for Ne^2+ + H and our theoretical estimates suggest that the electron capture cross sections for these strongly exoergic collision systems drop slower toward low collision energies than expected from previous theories. We perform a theoretical study to establish and understand the true nature of this controversy. The calculations are based on the Hidden Crossings MOCC method, augmented with rotational and turning point effects.
Electronic structure of disordered CuPd alloys: A two-dimensional positron-annihilation study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smedskjaer, L.C.; Benedek, R.; Siegel, R.W.
1987-11-23
Two-dimensional--angular-correlation experiments using posi- tron-annihilation spectroscopy were performed on a series of disordered Cu-rich CuPd-alloy single crystals. The results are compared with theoretical calculations based on the Korringa-Kohn-Rostoker coherent-potential approximation. Our experiments confirm the theoretically predicted flattening of the alloy Fermi surface near (110) with increasing Pd concentration. The momentum densities and the two-dimensional--angular-correlation spectra around zero momentum exhibit a characteristic signature of the electronic states near the valence-band edge in the alloy.
Generation of radially polarized beams based on thermal analysis of a working cavity.
He, Guangyuan; Guo, Jing; Wang, Biao; Jiao, Zhongxing
2011-09-12
The laser oscillation and polarization behavior of a side-pumped Nd:YAG laser are studied theoretically and experimentally by a thermal model for a working cavity. We use this model along with the Magni method, which gives a new stability diagram, to show important characteristics of the resonator. High-power radially and azimuthally polarized laser beams are obtained with a Nd:YAG module in a plano-plano cavity. Special regions and thermal hysteresis loops are observed in the experiments, which are concordant with the theoretical predictions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yueqi; Lava, Pascal; Reu, Phillip
This study presents a theoretical uncertainty quantification of displacement measurements by subset-based 2D-digital image correlation. A generalized solution to estimate the random error of displacement measurement is presented. The obtained solution suggests that the random error of displacement measurements is determined by the image noise, the summation of the intensity gradient in a subset, the subpixel part of displacement, and the interpolation scheme. The proposed method is validated with virtual digital image correlation tests.
Wang, Yueqi; Lava, Pascal; Reu, Phillip; ...
2015-12-23
This study presents a theoretical uncertainty quantification of displacement measurements by subset-based 2D-digital image correlation. A generalized solution to estimate the random error of displacement measurement is presented. The obtained solution suggests that the random error of displacement measurements is determined by the image noise, the summation of the intensity gradient in a subset, the subpixel part of displacement, and the interpolation scheme. The proposed method is validated with virtual digital image correlation tests.
Theoretical proposal for determining angular momentum compensation in ferrimagnets
NASA Astrophysics Data System (ADS)
Zhu, Zhifeng; Fong, Xuanyao; Liang, Gengchiau
2018-05-01
This work demonstrates that the magnetization and angular momentum compensation temperatures (TMC and TAMC) in ferrimagnets can be unambiguously determined by performing two sets of temperature-dependent current switching, with the symmetry reversals at TMC and TAMC, respectively. A theoretical model based on the modified Landau-Lifshitz-Bloch equation is developed to systematically study the spin torque effect under different temperatures, and numerical simulations are performed to corroborate our proposal. Furthermore, we demonstrate that the recently reported linear relation between TAMC and TMC can be explained using the Curie-Weiss theory.
Fabricatable nanopore sensors with an atomic thickness
NASA Astrophysics Data System (ADS)
Luan, Binquan; Bai, Jingwei; Stolovitzky, Gustavo
2013-10-01
When analyzing biological molecules (such as DNA and proteins) transported through a nanopore sensor, the pore length limits both the sensitivity and the spatial resolution. Atomically thin as a graphene nanopore is, it is difficult to make graphene pores and the scalable-fabrication of those pores has not yet been possible. We theoretically studied a type of atomically thin nanopores that are formed by intersection of two perpendicular nano-slits. Based on theoretical analyses, we demonstrate that slit nanopores behave similarly to graphene pores and can be manufactured at a wafer scale.
1991-09-01
review of past CBI studies -was conducted to provide the researcher a theoretical knowledge base on the effectiveness and efficiency of CBI. A summary...Literature Review Findinms on Ways to Measure CBI Effectiveness and Efficiency. The literature included previously conducted CBI experiments, studies , and...nine choices on each main and submenu (14:16). 3) Allow the student to make a menu selection with upper or lower case entries (28:291). 4) Prevent
2014-01-01
Background Internet-based physical activity interventions have great potential in supporting patients in cardiac rehabilitation. Health behavior change theories and user input are identified as important contributors in the effectiveness of the interventions, but they are rarely combined in a systematic way in the design of the interventions. Objective The aim of this study is to identify the appropriate theoretical framework, along with the needs of the users of a physical activity intervention for cardiac rehabilitation, and to combine them into an effective Internet- and mobile-based intervention. Methods We explain the theoretical framework of the intervention in a narrative overview of the existing health behavior change literature as it applies to physical activity. We also conducted a focus group with 11 participants of a cardiac rehabilitation program and used thematic analysis to identify and analyze patterns of meaning in the transcribed data. Results We chose stage-based approaches, specifically the transtheoretical model and the health action process approach as our main framework for tailoring, supplemented with other theoretical concepts such as regulatory focus within the appropriate stages. From the thematic analysis of the focus group data, we identified seven themes: (1) social, (2) motivation, (3) integration into everyday life, (4) information, (5) planning, (6) monitoring and feedback, and (7) concerns and potential problems. The final design of the intervention was based on both the theoretical review and the user input, and it is explained in detail. Conclusions We applied a combination of health behavioral theory and user input in designing our intervention. We think this is a promising design approach with the potential to combine the high efficacy of theory-based interventions with the higher perceived usefulness of interventions designed according to user input. Trial Registration Clinicaltrials.gov NCT01223170; http://clinicaltrials.gov/show/NCT01223170 (Archived by WebCite at http://www.webcitation.org/6M5FqT9Q2). PMID:24413185
Arshad, Muhammad Nadeem; Bibi, Aisha; Mahmood, Tariq; Asiri, Abdullah M; Ayub, Khurshid
2015-04-03
We report here a comparative theoretical and experimental study of four triazine-based hydrazone derivatives. The hydrazones are synthesized by a three step process from commercially available benzil and thiosemicarbazide. The structures of all compounds were determined by using the UV-Vis., FT-IR, NMR (1H and 13C) spectroscopic techniques and finally confirmed unequivocally by single crystal X-ray diffraction analysis. Experimental geometric parameters and spectroscopic properties of the triazine based hydrazones are compared with those obtained from density functional theory (DFT) studies. The model developed here comprises of geometry optimization at B3LYP/6-31G (d, p) level of DFT. Optimized geometric parameters of all four compounds showed excellent correlations with the results obtained from X-ray diffraction studies. The vibrational spectra show nice correlations with the experimental IR spectra. Moreover, the simulated absorption spectra also agree well with experimental results (within 10-20 nm). The molecular electrostatic potential (MEP) mapped over the entire stabilized geometries of the compounds indicated their chemical reactivates. Furthermore, frontier molecular orbital (electronic properties) and first hyperpolarizability (nonlinear optical response) were also computed at the B3LYP/6-31G (d, p) level of theory.
Explicit and implicit assessment of gender roles.
Fernández, Juan; Quiroga, M Ángeles; Escorial, Sergio; Privado, Jesús
2014-05-01
Gender roles have been assessed by explicit measures and, recently, by implicit measures. In the former case, the theoretical assumptions have been questioned by empirical results. To solve this contradiction, we carried out two concatenated studies based on a relatively well-founded theoretical and empirical approach. The first study was designed to obtain a sample of genderized activities of the domestic sphere by means of an explicit assessment. Forty-two raters (22 women and 20 men, balanced on age, sex, and level of education) took part as raters. In the second study, an implicit assessment of gender roles was carried out, focusing on the response time given to the sample activities obtained from the first study. A total of 164 adults (90 women and 74 men, mean age = 43), with experience in living with a partner and balanced on age, sex, and level of education, participated. Taken together, results show that explicit and implicit assessment converge. The current social reality shows that there is still no equity in some gender roles in the domestic sphere. These consistent results show considerable theoretical and empirical robustness, due to the double implicit and explicit assessment.
Tourassi, Georgia D; Harrawood, Brian; Singh, Swatee; Lo, Joseph Y; Floyd, Carey E
2007-01-01
The purpose of this study was to evaluate image similarity measures employed in an information-theoretic computer-assisted detection (IT-CAD) scheme. The scheme was developed for content-based retrieval and detection of masses in screening mammograms. The study is aimed toward an interactive clinical paradigm where physicians query the proposed IT-CAD scheme on mammographic locations that are either visually suspicious or indicated as suspicious by other cuing CAD systems. The IT-CAD scheme provides an evidence-based, second opinion for query mammographic locations using a knowledge database of mass and normal cases. In this study, eight entropy-based similarity measures were compared with respect to retrieval precision and detection accuracy using a database of 1820 mammographic regions of interest. The IT-CAD scheme was then validated on a separate database for false positive reduction of progressively more challenging visual cues generated by an existing, in-house mass detection system. The study showed that the image similarity measures fall into one of two categories; one category is better suited to the retrieval of semantically similar cases while the second is more effective with knowledge-based decisions regarding the presence of a true mass in the query location. In addition, the IT-CAD scheme yielded a substantial reduction in false-positive detections while maintaining high detection rate for malignant masses.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tourassi, Georgia D.; Harrawood, Brian; Singh, Swatee
The purpose of this study was to evaluate image similarity measures employed in an information-theoretic computer-assisted detection (IT-CAD) scheme. The scheme was developed for content-based retrieval and detection of masses in screening mammograms. The study is aimed toward an interactive clinical paradigm where physicians query the proposed IT-CAD scheme on mammographic locations that are either visually suspicious or indicated as suspicious by other cuing CAD systems. The IT-CAD scheme provides an evidence-based, second opinion for query mammographic locations using a knowledge database of mass and normal cases. In this study, eight entropy-based similarity measures were compared with respect to retrievalmore » precision and detection accuracy using a database of 1820 mammographic regions of interest. The IT-CAD scheme was then validated on a separate database for false positive reduction of progressively more challenging visual cues generated by an existing, in-house mass detection system. The study showed that the image similarity measures fall into one of two categories; one category is better suited to the retrieval of semantically similar cases while the second is more effective with knowledge-based decisions regarding the presence of a true mass in the query location. In addition, the IT-CAD scheme yielded a substantial reduction in false-positive detections while maintaining high detection rate for malignant masses.« less
ERIC Educational Resources Information Center
Nonnenmacher, Alexandra; Friedrichs, Jurgen
2013-01-01
To explain country differences in an analytical or structural dependent variable, the application of a macro-micro-model containing contextual hypotheses is necessary. Our methodological study examines whether empirical studies apply such a model. We propose that a theoretical base for country differences is well described in multilevel studies,…
"Many Moons": Understanding Teacher Learning from a Teacher Education Perspective. Issue Paper 88-5.
ERIC Educational Resources Information Center
McDiarmid, G. Williamson; Ball, Deborah Loewenberg
The Teacher Education and Learning to Teach Study of the National Center for Research on Teacher Education combines case studies of teacher education programs with longitudinal studies of teacher learning. In this paper, the development of the theoretical framework on which instrumentation for the longitudinal study is based is discussed.…
Frierson, Georita M; Morrow, James R; Vidales, Andrew
2012-01-01
Researchers studying physical activity often face challenges dealing with recruitment and resources, particularly when conducting longitudinal Internet-based research. Commonly raised methodological problems such as minority recruitment, participant commitment, and participant-staff involvement are addressed through a theoretically driven recruitment and adherence protocol in The Women's Exercise Injuries: Incidence and Risk Factors (WIN) Internet-based study. The objectives of this paper were to review and suggest solutions to problems of: (1) low recruitment of diverse samples, (2) low adherence, and (3) staffing needs. We recruited 1303 community-dwelling women and followed them through a multiple-phase, longitudinal, Internet-based study. Recruitment and adherence data were analyzed through descriptive methods and logistic regressions to examine participant adherence and sociodemographic factors and predictors of who entered the long-term phase of the study. We successfully retained 71.6% of the sample through 4 recruitment phases. Twenty-seven percent of the initially recruited sample was racial/ethnically diverse, 24% began the long-term phase, and 23% completed. Several strategies to enhance participant commitment were successfully used during the practice phase, providing a successful, low staff to participant ratio. Logistic regression indicated being married, being older, and having greater Internet skills were predictive of successfully entering the long-term phase of the study. Recruitment and compliance protocols were successful in meeting overall and racial/ethnic enrollment and recruitment goals. The theoretically based practice phase techniques were successful in re-engaging noncompliant participants. Strategies for minority enrollment and compliance are evaluated.
Arreciado Marañón, Antonia; Isla Pera, Ma Pilar
2015-07-01
The problem of nurses' professional identity continues to be seen in the disjunction between theoretical training and clinical placements. Moreover, it is not known how nursing students perceive these contradictions or how this discrepancy influences the construction of professional identity. To gain insight into nursing students' perception of their theoretical and practical training and how this training influences the process of constructing their professional identity. Qualitative, ethnographic study. Third-year nursing students at the l'Escola Universitària d'Infermeria Vall d'Hebron de Barcelona. Participant observation was conducted in the hospital setting and primary care. Discussion groups were held. The constant comparative method was used for the analysis. The study adhered to the criteria of credibility, transferability, dependability and confirmability. Students believed that both theoretical and practical trainings were indispensable. Nevertheless, clinical placements were considered essential to confer sense to the theory and to shape their identity, as they helped student nurses to experience their future professional reality and to compare it with what they had been taught in theoretical and academic classes. The role of the clinical placement mentor was essential. With regard to theory, the skills developed in problem-based learning gave novice nurses' confidence to approach the problems of daily practice and new situations. Equally, this approach taught them to reflect on what they did and what they were taught and this ability was transferred to the clinical setting. For students, both strategies (theory and practice) are vital to nursing education and the construction of a professional identity, although pride of place is given to clinical placements and mentors. The skills developed with problem-based learning favor active and reflective learning and are transferred to learning in the clinical setting. Copyright © 2015 Elsevier Ltd. All rights reserved.
Chahine, Saad; Cristancho, Sayra; Padgett, Jessica; Lingard, Lorelei
2017-06-01
In the competency-based medical education (CBME) approach, clinical competency committees are responsible for making decisions about trainees' competence. However, we currently lack a theoretical model for group decision-making to inform this emerging assessment phenomenon. This paper proposes an organizing framework to study and guide the decision-making processes of clinical competency committees.This is an explanatory, non-exhaustive review, tailored to identify relevant theoretical and evidence-based papers related to small group decision-making. The search was conducted using Google Scholar, Web of Science, MEDLINE, ERIC, and PsycINFO for relevant literature. Using a thematic analysis, two researchers (SC & JP) met four times between April-June 2016 to consolidate the literature included in this review.Three theoretical orientations towards group decision-making emerged from the review: schema, constructivist, and social influence. Schema orientations focus on how groups use algorithms for decision-making. Constructivist orientations focus on how groups construct their shared understanding. Social influence orientations focus on how individual members influence the group's perspective on a decision. Moderators of decision-making relevant to all orientations include: guidelines, stressors, authority, and leadership.Clinical competency committees are the mechanisms by which groups of clinicians will be in charge of interpreting multiple assessment data points and coming to a shared decision about trainee competence. The way in which these committees make decisions can have huge implications for trainee progression and, ultimately, patient care. Therefore, there is a pressing need to build the science of how such group decision-making works in practice. This synthesis suggests a preliminary organizing framework that can be used in the implementation and study of clinical competency committees.
Density functional theory and phytochemical study of 8-hydroxyisodiospyrin
NASA Astrophysics Data System (ADS)
Ullah, Zakir; Ata-ur-Rahman; Fazl-i-Sattar; Rauf, Abdur; Yaseen, Muhammad; Hassan, Waseem; Tariq, Muhammad; Ayub, Khurshid; Tahir, Asif Ali; Ullah, Habib
2015-09-01
Comprehensive theoretical and experimental studies of a natural product, 8-hydroxyisodiospyrin (HDO) have been carried out. Based on the correlation of experimental and theoretical data, an appropriate computational model was developed for obtaining the electronic, spectroscopic, and thermodynamic parameters of HDO. First of all, the exact structure of HDO is confirmed from the nice correlation of theory and experiment, prior to determination of its electroactive nature. Hybrid density functional theory (DFT) is employed for all theoretical simulations. The experimental and predicted IR and UV-vis spectra [B3LYP/6-31+G(d,p) level of theory] have excellent correlation. Inter-molecular non-covalent interaction of HDO with different gases such as NH3, CO2, CO, H2O is investigated through geometrical counterpoise (gCP) i.e., B3LYP-gCP-D3/6-31G∗ method. Furthermore, the inter-molecular interaction is also supported by geometrical parameters, electronic properties, thermodynamic parameters and charge analysis. All these characterizations have corroborated each other and confirmed the electroactive nature (non-covalent interaction ability) of HDO for the studied gases. Electronic properties such as Ionization Potential (IP), Electron Affinities (EA), electrostatic potential (ESP), density of states (DOS), HOMO, LUMO, and band gap of HDO have been estimated for the first time theoretically.
On Tradeoffs between Trust and Survivability using a Game Theoretic Approach
2016-04-13
On Tradeoffs between Trust and Survivability using a Game Theoretic Approach Jin-Hee Cho and Ananthram Swami U.S. Army Research Laboratory...introduces a game theoretic approach, namely Aoyagi’s game theory based on positive collusion of players. This approach improves group trust by...communication and networking field [17]. We employ a game theoretic approach, namely Aoyagi’s game theory [2], to introduce the concept of positive
IMMAN: free software for information theory-based chemometric analysis.
Urias, Ricardo W Pino; Barigye, Stephen J; Marrero-Ponce, Yovani; García-Jacas, César R; Valdes-Martiní, José R; Perez-Gimenez, Facundo
2015-05-01
The features and theoretical background of a new and free computational program for chemometric analysis denominated IMMAN (acronym for Information theory-based CheMoMetrics ANalysis) are presented. This is multi-platform software developed in the Java programming language, designed with a remarkably user-friendly graphical interface for the computation of a collection of information-theoretic functions adapted for rank-based unsupervised and supervised feature selection tasks. A total of 20 feature selection parameters are presented, with the unsupervised and supervised frameworks represented by 10 approaches in each case. Several information-theoretic parameters traditionally used as molecular descriptors (MDs) are adapted for use as unsupervised rank-based feature selection methods. On the other hand, a generalization scheme for the previously defined differential Shannon's entropy is discussed, as well as the introduction of Jeffreys information measure for supervised feature selection. Moreover, well-known information-theoretic feature selection parameters, such as information gain, gain ratio, and symmetrical uncertainty are incorporated to the IMMAN software ( http://mobiosd-hub.com/imman-soft/ ), following an equal-interval discretization approach. IMMAN offers data pre-processing functionalities, such as missing values processing, dataset partitioning, and browsing. Moreover, single parameter or ensemble (multi-criteria) ranking options are provided. Consequently, this software is suitable for tasks like dimensionality reduction, feature ranking, as well as comparative diversity analysis of data matrices. Simple examples of applications performed with this program are presented. A comparative study between IMMAN and WEKA feature selection tools using the Arcene dataset was performed, demonstrating similar behavior. In addition, it is revealed that the use of IMMAN unsupervised feature selection methods improves the performance of both IMMAN and WEKA supervised algorithms. Graphic representation for Shannon's distribution of MD calculating software.
ERIC Educational Resources Information Center
Robinson-Hill, Rona M.
2013-01-01
What affect does female participation in the Training Future Scientist (TFS) program based on Vygotsky's sociocultural theory and Maslow's Hierarchies of Needs have on female adolescents' achievement levels in science and their attitude toward science and interest in science-based careers? The theoretical framework for this study was developed…
ERIC Educational Resources Information Center
Liu, Tzu-Chien
2005-01-01
Instructional planning is an essential professional activity often used by teachers. However, some characteristics of existing university-based teacher education programs may hamper pre-service teachers' learning of instructional planning. Thus, this study adopts the cognitive apprenticeship as a theoretical foundation to construct a web-based…
ERIC Educational Resources Information Center
Corazon, Sus S.; Schilhab, Theresa S. S.; Stigsdotter, Ulrika K.
2011-01-01
This paper theoretically examines the interplay between cognition and bodily involvement in relation to nature-based therapy and proposes implications for practice. With support from theory within embodied cognition and neuroscientific studies, it is argued that explicit learning is actively supported by bodily involvement with the environment.…
A Study on the Mobile Learning of English and American Literature Based on WeChat Public Account
ERIC Educational Resources Information Center
Dai, Guiyu; Liu, Yang; Cui, Shanmeng
2018-01-01
This paper uses Edgar Dale's Audio-visual Learning Theory and Jean Piaget's Constructionist Learning Theory as the theoretical framework to conduct two control experimental tests and a questionnaire research to investigate students' impression and expectations toward WeChat public account based mobile learning mode as well as its validity,…
An Acceptance and Mindfulness-Based Approach to Social Phobia: A Case Study
ERIC Educational Resources Information Center
Brady, Victoria Popick; Whitman, Sarah M.
2012-01-01
Over the past few years, there has been a proliferation of theoretical discussions and empirical research on the use of acceptance and mindfulness-based therapies to treat anxiety disorders. Because these treatment approaches are in their infancy, many clinicians may still be uncertain about how to apply such treatments in their work with clients.…
The Effect of Accelerated Reader on Reading Scores in a Rural School District
ERIC Educational Resources Information Center
Hunter, Teresa A.
2013-01-01
In this study, the implementation of Accelerated Reader (AR), a computer-assisted supplemental reading program, was investigated as a research-based instructional strategy to assess whether it aided a high-performing, rural school district in meeting adequate yearly progress goals. The theoretical framework was based on Vygotsky's zone of…
Reviving the Ancient Virtues in the Scholarship of Teaching, with a Slight Critical Twist
ERIC Educational Resources Information Center
Kreber, Carolin
2015-01-01
This conceptual study argues that the scholarship of teaching is not just an evidence-based but also a virtues-based practice. To this end, it pursues two interrelated objectives. First, it seeks to show that the scholarship of teaching is supported by the "intellectual" virtues of "episteme" (theoretical knowledge),…
ERIC Educational Resources Information Center
Gao, Su; Wang, Jian
2016-01-01
Students' frequent exposure to inquiry-based science teaching is presumed more effective than their exposure to traditional didactic instruction in helping improve competence in content knowledge and problem solving. Framed through theoretical perspectives of inquiry-based instruction and culturally relevant pedagogy, this study examines this…
ERIC Educational Resources Information Center
Earhart, James; Zamora, Irina
2015-01-01
This pilot study describes the development and initial implementation of a treatment program that uses relationship-based techniques as a basis for promoting characteristics important in learning and emotional regulation. A case example has been included as an illustration of the theoretical framework of this intervention, along with preliminary…
What's Growing on Here? Garden-Based Pedagogy in a Concrete Jungle
ERIC Educational Resources Information Center
Jagger, Susan; Sperling, Erin; Inwood, Hilary
2016-01-01
This study explores experiences of a learning garden project at an urban faculty of education. The project opens a space for the theoretical and practical consideration of garden-based pedagogies and their influence on university students, educators, and the community as a whole. The learning garden was created by a small group of initial teacher…
ERIC Educational Resources Information Center
Hatzichristou, Chryse; Lianos, Panayiotis; Lampropoulou, Aikaterini
2017-01-01
In this study, an evidence-based program aiming to promote psychological well-being and resilience within the context of Greek schools is presented. It is based upon a multidimensional model that synthesizes different theoretical domains, placing emphasis on different goals depending on the needs of the school community during unsettling times.…
Firm-Specific Marketing Capital and Job Satisfaction of Marketers: Evidence from Vietnam
ERIC Educational Resources Information Center
Nguyen, Tho D.; Nguyen, Trang T. M.
2011-01-01
Purpose: Based on the resource-based view of the firm, this study aims to examine antecedents and outcomes of firm-specific marketing capital pool invested by marketers in a transition market, Vietnam. Design/methodology/approach: A sample of 528 marketers in Ho Chi Minh City was surveyed to test the theoretical model. Structural equation…
ERIC Educational Resources Information Center
Nguyen, ThuyUyen H.; Charity, Ian; Robson, Andrew
2016-01-01
This study investigates students' perceptions of computer-based learning environments, their attitude towards business statistics, and their academic achievement in higher education. Guided by learning environments concepts and attitudinal theory, a theoretical model was proposed with two instruments, one for measuring the learning environment and…
ERIC Educational Resources Information Center
Rajbhandari, Mani Man Singh
2018-01-01
Obstinate actions-oriented behaviour is the study of learning and practicing behaviour theoractively, which is acquired from the content based, process based learning and spawning critical reflexivity to the learnt theoretical phenomena into practical actions. Obstinate actions-oriented behaviour is a multi-faceted behaviour that is generally…
Toward Theory-Based Instruction in Scientific Problem Solving.
ERIC Educational Resources Information Center
Heller, Joan I.; And Others
Several empirical and theoretical analyses related to scientific problem-solving are reviewed, including: detailed studies of individuals at different levels of expertise, and computer models simulating some aspects of human information processing during problem solving. Analysis of these studies has revealed many facets about the nature of the…
Developing Instructional Leaders through Assistant Principals' Academy: A Partnership for Success
ERIC Educational Resources Information Center
Gurley, D. Keith; Anast-May, Linda; Lee, H. T.
2015-01-01
This article describes findings from a single-case qualitative study of a unique 2-year professional development academy for practicing assistant principals designed and implemented in partnership between school district personnel and university educational leadership faculty members. The study was conducted based on the theoretical framework of…
Online Fan Fiction, Global Identities, and Imagination
ERIC Educational Resources Information Center
Black, Rebecca W.
2009-01-01
Based on longitudinal data from a three year ethnographic study, this article uses discourse analytic methods to explore the literacy and social practices of three adolescent English language learners writing in an online fan fiction community. Theoretical constructs within globalization and literacy studies are used to describe the influences of…
Theoretical Frameworks for Studying Female Marriage Migrants
ERIC Educational Resources Information Center
Merali, Noorfarah
2008-01-01
Transnational marriages account for a significant proportion of family-based immigration to North America. An increasing number of immigrant men are choosing to marry women from their countries of origin, and an increasing number of nonimmigrant men are choosing to marry women from other countries. Existing studies on the experiences of foreign…
Elementary Teachers' Perceptions of Administrators and Job Satisfaction
ERIC Educational Resources Information Center
Davis, Christen M.
2012-01-01
The purpose of this study was to investigate administrative influence on teacher job satisfaction based on the perspectives of teachers using Frederick Herzberg, Bernard Mausner, and Barbara Snyderman's Two-Factor Theory on job satisfaction as the theoretical framework. This study also explored the administrative actions and behaviors that…
Creativity in Fashion Design Students
ERIC Educational Resources Information Center
Robinson, Joyce Robin
2011-01-01
The purpose of this study was to examine relationships among environmental influences, changes in domain specific knowledge, and changes in tolerance of ambiguity as well as changes in creativity of individuals majoring in fashion design at four-year universities. This study was based on the confluence theoretical approach which holds that…
The Development and Validation of a Scale Measuring Teacher Autonomous Behaviour
ERIC Educational Resources Information Center
Evers, Arnoud T.; Verboon, Peter; Klaeijsen, Andrea
2017-01-01
In the current study a multi-dimensional scale that measures teacher autonomous behaviour is presented. The scale is applicable across the following educational sectors: primary education, secondary education and vocational education. Based on an elaborate literature study, four theoretically relevant dimensions of teacher autonomous behaviour…
Beginning Teachers' Perceptions of In-School and In-Profession Mentoring Relationships
ERIC Educational Resources Information Center
Greiman, Bradley C.; Torres, Robert M.; Burris, Scott; Kitchel, Tracy
2007-01-01
The purpose of this study was to compare two different formal mentoring relationships based on the perceptions of beginning teachers regarding their dyadic interactions. Kram's mentor role theory and Byrne's similarity-attraction paradigm served as the theoretical foundation for the study. The specific variables of interest included psychosocial…
Native and Nonnative Processing of Japanese Pitch Accent
ERIC Educational Resources Information Center
Wu, Xianghua; Tu, Jung-Yueh; Wang, Yue
2012-01-01
The theoretical framework of this study is based on the prevalent debate of whether prosodic processing is influenced by higher level linguistic-specific circuits or reflects lower level encoding of physical properties. Using the dichotic listening technique, the study investigates the hemispheric processing of Japanese pitch accent by native…
Relapse and Recurrence Prevention in the Treatment for Adolescents with Depression Study
ERIC Educational Resources Information Center
Simons, Anne D.; Rohde, Paul; Kennard, Betsy D.; Robins, Michele
2005-01-01
Relapse and recurrence in adolescent depression are important problems. Much less is known about relapse prevention compared to the acute treatment of depression in adolescents. Based on previous research, theoretical predictions, and clinical experience, the Treatment for Adolescents With Depression Study (TADS) protocol was designed to determine…
Online Resources in Mathematics, Teachers' Geneses and Didactical Techniques
ERIC Educational Resources Information Center
Bueno-Ravel, Laetitia; Gueudet, Ghislaine
2009-01-01
The study we present here concerns the consequences of integrating online resources into the teaching of mathematics. We focus on the interaction between teachers and specific online resources they draw on: e-exercise bases. We propose a theoretical approach to study the associated phenomena, combining instrumental and anthropological…
NASA Astrophysics Data System (ADS)
Suresha, B. L.; Sumantha, H. S.; Salman, K. Mohammed; Pramod, N. G.; Abhiram, J.
2018-04-01
The ionization potential is usually found to be less in acid and more in base. The experiment proves that the ionization potential increases on dilution of acid to base and reduces from base to acid. The potential can be tailored according to the desired properties based on our choice of acid or base. The experimental study establishes a direct relationship between pH and electric potential. This work provides theoretical insights on the need for a basic media of pH 10 in chemical thin film growth techniques called Chemical Bath Deposition Techniques.
The cosmological lithium problem revisited
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bertulani, C. A., E-mail: carlos.bertulani@tamuc.edu; Department of Physics and Astronomy, Texas A&M University, College Station, TX 75429; Mukhamedzhanov, A. M., E-mail: akram@comp.tamu.edu
After a brief review of the cosmological lithium problem, we report a few recent attempts to find theoretical solutions by our group at Texas A&M University (Commerce & College Station). We will discuss our studies on the theoretical description of electron screening, the possible existence of parallel universes of dark matter, and the use of non-extensive statistics during the Big Bang nucleosynthesis epoch. Last but not least, we discuss possible solutions within nuclear physics realm. The impact of recent measurements of relevant nuclear reaction cross sections for the Big Bang nucleosynthesis based on indirect methods is also assessed. Although ourmore » attempts may not able to explain the observed discrepancies between theory and observations, they suggest theoretical developments that can be useful also for stellar nucleosynthesis.« less
Wang, Xu; Zhang, Xuejun
2009-02-10
This paper is based on a microinteraction principle of fabricating a RB-SiC material with a fixed abrasive. The influence of the depth formed on a RB-SiC workpiece by a diamond abrasive on the material removal rate and the surface roughness of an optical component are quantitatively discussed. A mathematical model of the material removal rate and the simulation results of the surface roughness are achieved. In spite of some small difference between the experimental results and the theoretical anticipation, which is predictable, the actual removal rate matches the theoretical prediction very well. The fixed abrasive technology's characteristic of easy prediction is of great significance in the optical fabrication industry, so this brand-new fixed abrasive technology has wide application possibilities.
NASA Astrophysics Data System (ADS)
Koley, Susmita; Ghosh, Indranil
Quick and periodic inflow-outflow of adsorbate in an adsorbent column createsa differential temperature between the two ends of it, allowing for the generation of continuous sorption cooling in a single adsorbent tube. The concept has been proven experimentally and theoretically for near room temperature applications using activated carbon-nitrogen. The feasibility of generating continuous solid sorption cooling in a single adsorbent tube in the cryogenic domainhas been studied theoretically with a different adsorbent-adsorbate pair, namely, activated carbon-hydrogen. Precooling of gaseous hydrogen (before it enters the adsorbent column) and removal of the heat of adsorption has been achieved using liquid nitrogen. Theoretical estimation shows nearly 20 K temperature difference between the two ends under no load condition. Finally, parametric variations have been performed.
NASA Technical Reports Server (NTRS)
Olson, L. E.; Dvorak, F. A.
1975-01-01
The viscous subsonic flow past two-dimensional and infinite-span swept multi-component airfoils is studied theoretically and experimentally. The computerized analysis is based on iteratively coupled boundary layer and potential flow analysis. The method, which is restricted to flows with only slight separation, gives surface pressure distribution, chordwise and spanwise boundary layer characteristics, lift, drag, and pitching moment for airfoil configurations with up to four elements. Merging confluent boundary layers are treated. Theoretical predictions are compared with an exact theoretical potential flow solution and with experimental measures made in the Ames 40- by 80-Foot Wind Tunnel for both two-dimensional and infinite-span swept wing configurations. Section lift characteristics are accurately predicted for zero and moderate sweep angles where flow separation effects are negligible.
NASA Astrophysics Data System (ADS)
Chen, Hui; Cai, Li-Xun
2018-04-01
Based on the power-law stress-strain relation and equivalent energy principle, theoretical equations for converting between Brinell hardness (HB), Rockwell hardness (HR), and Vickers hardness (HV) were established. Combining the pre-existing relation between the tensile strength ( σ b ) and Hollomon parameters ( K, N), theoretical conversions between hardness (HB/HR/HV) and tensile strength ( σ b ) were obtained as well. In addition, to confirm the pre-existing σ b -( K, N) relation, a large number of uniaxial tensile tests were conducted in various ductile materials. Finally, to verify the theoretical conversions, plenty of statistical data listed in ASTM and ISO standards were adopted to test the robustness of the converting equations with various hardness and tensile strength. The results show that both hardness conversions and hardness-strength conversions calculated from the theoretical equations accord well with the standard data.
Torque limit of PM motors for field-weakening region operation
Royak, Semyon [Beachwood, OH; Harbaugh, Mark M [Richfield, OH
2012-02-14
The invention includes a motor controller and technique for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by receiving a torque command, determining a physical torque limit based on a stator frequency, determining a theoretical torque limit based on a maximum available voltage and motor inductance ratio, and limiting the torque command to the smaller of the physical torque limit and the theoretical torque limit. Receiving the torque command may include normalizing the torque command to obtain a normalized torque command, determining the physical torque limit may include determining a normalized physical torque limit, determining a theoretical torque limit may include determining a normalized theoretical torque limit, and limiting the torque command may include limiting the normalized torque command to the smaller of the normalized physical torque limit and the normalized theoretical torque limit.
Bhowmik, Arka; Repaka, Ramjee; Mulaveesala, Ravibabu; Mishra, Subhash C
2015-07-01
A theoretical study on the quantification of surface thermal response of cancerous human skin using the frequency modulated thermal wave imaging (FMTWI) technique has been presented in this article. For the first time, the use of the FMTWI technique for the detection and the differentiation of skin cancer has been demonstrated in this article. A three dimensional multilayered skin has been considered with the counter-current blood vessels in individual skin layers along with different stages of cancerous lesions based on geometrical, thermal and physical parameters available in the literature. Transient surface thermal responses of melanoma during FMTWI of skin cancer have been obtained by integrating the heat transfer model for biological tissue along with the flow model for blood vessels. It has been observed from the numerical results that, flow of blood in the subsurface region leads to a substantial alteration on the surface thermal response of the human skin. The alteration due to blood flow further causes a reduction in the performance of the thermal imaging technique during the thermal evaluation of earliest melanoma stages (small volume) compared to relatively large volume. Based on theoretical study, it has been predicted that the method is suitable for detection and differentiation of melanoma with comparatively large volume than the earliest development stages (small volume). The study has also performed phase based image analysis of the raw thermograms to resolve the different stages of melanoma volume. The phase images have been found to be clearly individuate the different development stages of melanoma compared to raw thermograms. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Chen, Min; Pukhov, Alexander; Peng, Xiao-Yu; Willi, Oswald
2008-10-01
Terahertz (THz) radiation from the interaction of ultrashort laser pulses with gases is studied both by theoretical analysis and particle-in-cell (PIC) simulations. A one-dimensional THz generation model based on the transient ionization electric current mechanism is given, which explains the results of one-dimensional PIC simulations. At the same time the relation between the final THz field and the initial transient ionization current is shown. One- and two-dimensional simulations show that for the THz generation the contribution of the electric current due to ionization is much larger than the one driven by the usual ponderomotive force. Ionization current generated by different laser pulses and gases is also studied numerically. Based on the numerical results we explain the scaling laws for THz emission observed in the recent experiments performed by Xie [Phys. Rev. Lett. 96, 075005 (2006)]. We also study the effective parameter region for the carrier envelop phase measurement by the use of THz generation.
Chen, Min; Pukhov, Alexander; Peng, Xiao-Yu; Willi, Oswald
2008-10-01
Terahertz (THz) radiation from the interaction of ultrashort laser pulses with gases is studied both by theoretical analysis and particle-in-cell (PIC) simulations. A one-dimensional THz generation model based on the transient ionization electric current mechanism is given, which explains the results of one-dimensional PIC simulations. At the same time the relation between the final THz field and the initial transient ionization current is shown. One- and two-dimensional simulations show that for the THz generation the contribution of the electric current due to ionization is much larger than the one driven by the usual ponderomotive force. Ionization current generated by different laser pulses and gases is also studied numerically. Based on the numerical results we explain the scaling laws for THz emission observed in the recent experiments performed by Xie et al. [Phys. Rev. Lett. 96, 075005 (2006)]. We also study the effective parameter region for the carrier envelop phase measurement by the use of THz generation.
The Information Architecture of E-Commerce: An Experimental Study on User Performance and Preference
NASA Astrophysics Data System (ADS)
Wan Mohd, Wan Abdul Rahim; Md Noor, Nor Laila; Mehad, Shafie
Too often, designers of e-commerce web sites use models, concepts, guidelines, and designs that focus on the artifacts while ignoring the context in which the artifacts will be used. Furthermore, the link between culture and usability in web site IA phenomenon is still considered as uncharted area, as it lacks much theoretical consideration. In an effort toward addressing the aforementioned issues, our study provides a theoretical and empirical link between cultural and usability through the application of ‘Venustas' (Delight) drawn from the architectural field and Hofstede's cultural dimensions. We use Islamic culture as the case study and report on the experiment to investigate the effect of the IA designs based on the cultural dimensions on e-commerce web sites. The result provides partial empirical support to the theorized link between culture and usability based on the usability measurement on user performance and preference. In addition, practical web site IA cultural design prescriptions are also provided.
NASA Astrophysics Data System (ADS)
Fruit, Michel; Gussarov, Andrei; Berghmans, Francis; Doyle, Dominic; Ulbrich, Gerd
2017-11-01
It is well known within the Space optics community that radiation may significantly affect transmittance of glasses. To overcome this drawback, glass manufacturers have developed Cerium doped counterparts of classical glasses. This doped glasses display much less transmittance sensitivity to radiation. Still, the impact of radiation on refractive index is less known and may affect indifferently classical or Cerium doped glasses. ESTEC has initialised an R&D program with the aim of establishing a comprehensive data base gathering radiation sensitivity data, called Dose coefficients, for all the glass optical parameters (transmittance / refractive index / compaction……). The first part of this study, to define the methodology for such a data base, is run by ASTRIUM SAS in co-operation with SCK CEN. This covers theoretical studies associated to testing of a selected set of classical and "radiation hardened" glasses. It is proposed here to present first the theoretical backgrounds of this study and then to give results which have been obtained so far.
A Combined Theoretical and Experimental Study for Silver Electroplating
Liu, Anmin; Ren, Xuefeng; An, Maozhong; Zhang, Jinqiu; Yang, Peixia; Wang, Bo; Zhu, Yongming; Wang, Chong
2014-01-01
A novel method combined theoretical and experimental study for environmental friendly silver electroplating was introduced. Quantum chemical calculations and molecular dynamic (MD) simulations were employed for predicting the behaviour and function of the complexing agents. Electronic properties, orbital information, and single point energies of the 5,5-dimethylhydantoin (DMH), nicotinic acid (NA), as well as their silver(I)-complexes were provided by quantum chemical calculations based on density functional theory (DFT). Adsorption behaviors of the agents on copper and silver surfaces were investigated using MD simulations. Basing on the data of quantum chemical calculations and MD simulations, we believed that DMH and NA could be the promising complexing agents for silver electroplating. The experimental results, including of electrochemical measurement and silver electroplating, further confirmed the above prediction. This efficient and versatile method thus opens a new window to study or design complexing agents for generalized metal electroplating and will vigorously promote the level of this research region. PMID:24452389
[Mathematical exploration of essence of herbal properties based on "Three-Elements" theory].
Jin, Rui; Zhao, Qian; Zhang, Bing
2014-10-01
Herbal property theory of traditional Chinese medicines is the theoretical guidance on authentication of medicinal plants, herborization, preparation of herbal medicines for decoction and clinical application, with important theoretical value and prac- tical significance. Our research team proposed the "three-element" theory for herbal properties for the first time, conducted a study by using combined methods of philology, chemistry, pharmacology and mathematics, and then drew the research conclusion that herbal properties are defined as the chemical compositions-based comprehensive expression with complex and multi-level (positive/negative) biological effects in specific organism state. In this paper, researchers made a systematic mathematical analysis in four aspects--the correlation between herbal properties and chemical component factors, the correlation between herbal properties and organism state fac- tor, the correlation between herbal properties and biological effect factor and the integration study of the three elements, proposed future outlook, and provided reference to mathematical studies and mathematical analysis of herbal properties.
Theoretical Bases for Teacher- and Peer-Delivered Sexual Health Promotion
ERIC Educational Resources Information Center
Wight, Daniel
2008-01-01
Purpose: This paper seeks to explore the theoretical bases for teacher-delivered and peer-delivered sexual health promotion and education. Design/methodology/approach: The first section briefly outlines the main theories informing sexual health interventions for young people, and the second discusses their implications for modes of delivery.…
Instructional Design: Science, Technology, Both, Neither
ERIC Educational Resources Information Center
Gropper, George L.
2017-01-01
What would it take for instructional design to qualify as a bona fide applied discipline? First and foremost, a fundamental requirement is a testable and tested theoretical base. Untested rationales until verified remain in limbo. Secondly, the discipline's applied prescriptions must be demonstrably traceable to the theoretical base once it is…
Family Counseling for All Counselors.
ERIC Educational Resources Information Center
Kaplan, David M.
Counselors whose specialty is marriage and family counseling develop a theoretical and research base and acquire countless hours of experience upon which to base their interventions. Most counselors and other helping professionals whose specialty is in another area do as well as they can lacking specific theoretical concepts and experience from…
NLPIR: A Theoretical Framework for Applying Natural Language Processing to Information Retrieval.
ERIC Educational Resources Information Center
Zhou, Lina; Zhang, Dongsong
2003-01-01
Proposes a theoretical framework called NLPIR that integrates natural language processing (NLP) into information retrieval (IR) based on the assumption that there exists representation distance between queries and documents. Discusses problems in traditional keyword-based IR, including relevance, and describes some existing NLP techniques.…
NASA Astrophysics Data System (ADS)
Ladewski, Barbara G.
Despite considerable exploration of inquiry and reflection in the literatures of science education and teacher education/teacher professional development over the past century, few theoretical or analytical tools exist to characterize these processes within a naturalistic classroom context. In addition, little is known regarding possible developmental trajectories for inquiry or reflection---for teachers or students---as these processes develop within a classroom context over time. In the dissertation, I use a sociocultural lens to explore these issues with an eye to the ways in which teachers and students develop shared sense-making, rather than from the more traditional perspective of individual teacher activity or student learning. The study includes both theoretical and empirical components. Theoretically, I explore the elaborations of sociocultural theory needed to characterize teacher-student shared sense-making as it develops within a classroom context, and, in particular, the role of inquiry and reflection in that sense-making. I develop a sociocultural model of shared sense-making that attempts to represent the dialectic between the individual and the social, through an elaboration of existing sociocultural and psychological constructs, including Vygotsky's zone of proximal development and theory of mind. Using this model as an interpretive framework, I develop a case study that explores teacher-student shared sense-making within a middle-school science classroom across a year of scaffolded introduction to inquiry-based science instruction. The empirical study serves not only as a test case for the theoretical model, but also informs our understanding regarding possible developmental trajectories and important mechanisms supporting and constraining shared sense-making within inquiry-based science classrooms. Theoretical and empirical findings provide support for the idea that perspectival shifts---that is, shifts of point-of-view that alter relationships and proximities of elements within the interaction space---play an important role in shared sense-making. Findings further suggest that the mutually constitutive interaction of inquiry and reflection plays a key role in flexible shared sense-making. Finally, findings lend support to the idea of a dialectical relationship between human models of shared sense-making and human systems of shared sense-making; that is, the ways in which human minds are coordinated is a work in progress, shaping and shaped by human culture.
NASA Astrophysics Data System (ADS)
Strom, C. S.; Bennema, P.
1997-03-01
A series of two articles discusses possible morphological evidence for oligomerization of growth units in the crystallization of tetragonal lysozyme, based on a rigorous graph-theoretic derivation of the F faces. In the first study (Part I), the growth layers are derived as valid networks satisfying the conditions of F slices in the context of the PBC theory using the graph-theoretic method implemented in program FFACE [C.S. Strom, Z. Krist. 172 (1985) 11]. The analysis is performed in monomeric and alternative tetrameric and octameric formulations of the unit cell, assuming tetramer formation according to the strongest bonds. F (flat) slices with thickness Rdhkl ( {1}/{2} < R ≤ 1 ) are predicted theoretically in the forms 1 1 0, 0 1 1, 1 1 1. The relevant energies are established in the broken bond model. The relation between possible oligomeric specifications of the unit cell and combinatorially feasible F slice compositions in these orientations is explored.
Fisher, Carla L.; Nussbaum, Jon F.
2015-01-01
Interpersonal communication is a fundamental part of being and key to health. Interactions within family are especially critical to wellness across time. Family communication is a central means of adaptation to stress, coping, and successful aging. Still, no theoretical argument in the discipline exists that prioritizes kin communication in health. Theoretical advances can enhance interventions and policies that improve family life. This article explores socioemotional selectivity theory (SST), which highlights communication in our survival. Communication partner choice is based on one's time perspective, which affects our prioritization of goals to survive—goals sought socially. This is a first test of SST in a family communication study on women's health and aging. More than 300 women of varying ages and health status participated. Two time factors, later adulthood and late-stage breast cancer, lead women to prioritize family communication. Findings provide a theoretical basis for prioritizing family communication issues in health reform. PMID:26997920
Fisher, Carla L; Nussbaum, Jon F
Interpersonal communication is a fundamental part of being and key to health. Interactions within family are especially critical to wellness across time. Family communication is a central means of adaptation to stress, coping, and successful aging. Still, no theoretical argument in the discipline exists that prioritizes kin communication in health. Theoretical advances can enhance interventions and policies that improve family life. This article explores socioemotional selectivity theory (SST), which highlights communication in our survival. Communication partner choice is based on one's time perspective, which affects our prioritization of goals to survive-goals sought socially. This is a first test of SST in a family communication study on women's health and aging. More than 300 women of varying ages and health status participated. Two time factors, later adulthood and late-stage breast cancer, lead women to prioritize family communication. Findings provide a theoretical basis for prioritizing family communication issues in health reform.
A Systematic Review of Rural, Theory-based Physical Activity Interventions.
Walsh, Shana M; Meyer, M Renée Umstattd; Gamble, Abigail; Patterson, Megan S; Moore, Justin B
2017-05-01
This systematic review synthesized the scientific literature on theory-based physical activity (PA) interventions in rural populations. PubMed, PsycINFO, and Web of Science databases were searched to identify studies with a rural study sample, PA as a primary outcome, use of a behavioral theory or model, randomized or quasi-experimental research design, and application at the primary and/or secondary level of prevention. Thirty-one studies met our inclusion criteria. The Social Cognitive Theory (N = 14) and Transtheoretical Model (N = 10) were the most frequently identified theories; however, most intervention studies were informed by theory but lacked higher-level theoretical application and testing. Interventions largely took place in schools (N = 10) and with female-only samples (N = 8). Findings demonstrated that theory-based PA interventions are mostly successful at increasing PA in rural populations but require improvement. Future studies should incorporate higher levels of theoretical application, and should explore adapting or developing rural-specific theories. Study designs should employ more rigorous research methods to decrease bias and increase validity of findings. Follow-up assessments to determine behavioral maintenance and/or intervention sustainability are warranted. Finally, funding agencies and journals are encouraged to adopt rural-urban commuting area codes as the standard for defining rural.
A theoretical approach to medication adherence for children and youth with psychiatric disorders.
Charach, Alice; Volpe, Tiziana; Boydell, Katherine M; Gearing, Robin E
2008-01-01
This article provides a theoretical review of treatment adherence for children and youth with psychiatric disorders where pharmacological agents are first-line interventions. Four empirically based models of health behavior are reviewed and applied to the sparse literature about medication adherence for children with attention-deficit/hyperactivity disorder and young people with first-episode psychosis. Three qualitative studies of medication use are summarized, and details from the first-person narratives are used to illustrate the theoretical models. These studies indicate, when taken together, that the clinical approach to addressing poor medication adherence in children and youth with psychiatric disorders should be guided by more than one theoretical model. Mental health experts should clarify beliefs, address misconceptions, and support exploration of alternative treatment options unless contraindicated. Recognizing the larger context of the family, allowing time for parents and children to change their attitudes, and offering opportunities for easy access to medication in the future are important ways of respecting patient preferences, while steering them toward best-evidence interventions. Future research using qualitative methods of inquiry to investigate parent, child, and youth experiences of mental health interventions should identify effective ways to improve treatment adherence.
Theoretical relationship between elastic wave velocity and electrical resistivity
NASA Astrophysics Data System (ADS)
Lee, Jong-Sub; Yoon, Hyung-Koo
2015-05-01
Elastic wave velocity and electrical resistivity have been commonly applied to estimate stratum structures and obtain subsurface soil design parameters. Both elastic wave velocity and electrical resistivity are related to the void ratio; the objective of this study is therefore to suggest a theoretical relationship between the two physical parameters. Gassmann theory and Archie's equation are applied to propose a new theoretical equation, which relates the compressional wave velocity to shear wave velocity and electrical resistivity. The piezo disk element (PDE) and bender element (BE) are used to measure the compressional and shear wave velocities, respectively. In addition, the electrical resistivity is obtained by using the electrical resistivity probe (ERP). The elastic wave velocity and electrical resistivity are recorded in several types of soils including sand, silty sand, silty clay, silt, and clay-sand mixture. The appropriate input parameters are determined based on the error norm in order to increase the reliability of the proposed relationship. The predicted compressional wave velocities from the shear wave velocity and electrical resistivity are similar to the measured compressional velocities. This study demonstrates that the new theoretical relationship may be effectively used to predict the unknown geophysical property from the measured values.
A theoretical and mass spectrometry study of the fragmentation of mycosporine-like amino acids
NASA Astrophysics Data System (ADS)
Cardozo, Karina H. M.; Vessecchi, Ricardo; Carvalho, Valdemir M.; Pinto, Ernani; Gates, Paul J.; Colepicolo, Pio; Galembeck, Sérgio E.; Lopes, Norberto P.
2008-06-01
In the present study, the mycosporine-like amino acids (MAAs) were isolated from the marine red alga Gracilaria tenuistipitata and analysed by high-resolution accurate-mass sequential mass spectrometry (MSn). In addition to the proposed fragmentation mechanism based on the MSn analysis, it is clearly demonstrated that the elimination of mass 15 is a radical processes taking place at the methoxyl substituent of the double bond. This characteristic loss of a methyl radical was studied by theoretical calculations and the homolytic cleavage of the OC bond is suggested to be dependent on the bond weakening. The protonation site of the MAAs was indicated by analysis of the Fukui functions and the relative Gibbs energies of the several possible protonated forms.
Computational models of neuromodulation.
Fellous, J M; Linster, C
1998-05-15
Computational modeling of neural substrates provides an excellent theoretical framework for the understanding of the computational roles of neuromodulation. In this review, we illustrate, with a large number of modeling studies, the specific computations performed by neuromodulation in the context of various neural models of invertebrate and vertebrate preparations. We base our characterization of neuromodulations on their computational and functional roles rather than on anatomical or chemical criteria. We review the main framework in which neuromodulation has been studied theoretically (central pattern generation and oscillations, sensory processing, memory and information integration). Finally, we present a detailed mathematical overview of how neuromodulation has been implemented at the single cell and network levels in modeling studies. Overall, neuromodulation is found to increase and control computational complexity.
Seward, Kirsty; Finch, Meghan; Yoong, Sze Lin; Wyse, Rebecca; Jones, Jannah; Grady, Alice; Wiggers, John; Nathan, Nicole; Conte, Kathleen; Wolfenden, Luke
2017-12-01
Children attending centre based childcare services consume as much as two thirds of their daily dietary requirements while in care. However, such services often fail to provide foods that are consistent with guideline recommendations. Developing strategies to improve childcare service adherence to menu dietary guidelines requires a comprehensive understanding of factors that may impede or promote implementation. The primary aim of this systematic review is to describe factors (barriers and facilitators) that may influence the implementation of menu dietary guidelines regarding food provision in centre-based childcare services and to map these factors to a theoretical framework. Over 7000 citations were identified from all sources. Duplicate abstracts were removed and selection criteria applied. Twelve studies (1994-2015) were included in the review. Dual data extraction was conducted and the reported factors were synthesised using the theoretical domains framework (TDF). Barriers and facilitators identified in qualitative studies were classified into 8 and 10 of the 14 TDF domains. Barriers and facilitators reported in quantitative studies covered 6 and 3 TDF domains respectively. The most common domain of which both barriers and facilitators to the implementation of menu dietary guidelines were identified was 'environmental context and resources'. This is the first study that comprehensively assesses literature to identify factors that influence the implementation of menu dietary guidelines in childcare services utilising a theoretical framework. Findings provide guidance to support researchers and policy makers design strategies to improve menu dietary guideline implementation and, as such have the potential to improve food provision in care. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Hamed Mashhadzadeh, A.; Fereidoon, Ab.; Ghorbanzadeh Ahangari, M.
2017-10-01
In current study we combined theoretical and experimental studies to evaluate the effect of functionalization and silanization on mechanical behavior of polymer-based/CNT nanocomposites. Epoxy was selected as thermoset polymer, polypropylene and poly vinyl chloride were selected as thermoplastic polymers. The whole procedure is divided to two sections . At first we applied density functional theory (DFT) to analyze the effect of functionalization on equilibrium distance and adsorption energy of unmodified, functionalized by sbnd OH group and silanized epoxy/CNT, PP/CNT and PVC/CNT nanocomposites and the results showed that functionalization increased adsorption energy and reduced the equilibrium distance in all studied nanocomposites and silanization had higher effect comparing to OH functionalizing. Then we prepared experimental samples of all mentioned nanocomposites and tested their tensile and flexural strength properties. The obtained results showed that functionalization increased the studied mechanical properties in all evaluated nanocomposites. Finally we compared the results of experimental and theoretical sections with each other and estimated a suitable agreement between these parts.
NASA Astrophysics Data System (ADS)
Xu-Xu, J.; Barrero-Gil, A.; Velazquez, A.
2015-11-01
This paper presents a theoretical study of the coupling between a vortex-induced vibration (VIV) cylindrical resonator and its associated linear electromagnetic generator. The two-equation mathematical model is based on a dual-mass formulation in which the dominant masses are the stator and translator masses of the generator. The fluid-structure interaction implemented in the model equations follows the so-called ‘advanced forcing model’ whose closure relies on experimental data. The rationale to carry out the study is the fact that in these types of configurations there is a two-way interaction between the moving parts in such a way that their motions influence each other simultaneously, thereby affecting the energy actually harvested. It is believed that instead of mainly resorting to complementary numerical simulations, a theoretical model can shed some light on the nature of the interaction and, at the same time, provide scaling laws that can be used for practical design and optimization purposes. It has been found that the proposed configuration has a maximum hydrodynamic to mechanical to electrical conversion efficiency (based on the VIV resonator oscillation amplitude) of 8%. For a cylindrical resonator 10 cm long with a 2 cm diameter, this translates into an output power of 20 to 160 mW for water stream velocities in the range from 0.5 to 1 m s-1.
Atkins, Lou; Francis, Jill; Islam, Rafat; O'Connor, Denise; Patey, Andrea; Ivers, Noah; Foy, Robbie; Duncan, Eilidh M; Colquhoun, Heather; Grimshaw, Jeremy M; Lawton, Rebecca; Michie, Susan
2017-06-21
Implementing new practices requires changes in the behaviour of relevant actors, and this is facilitated by understanding of the determinants of current and desired behaviours. The Theoretical Domains Framework (TDF) was developed by a collaboration of behavioural scientists and implementation researchers who identified theories relevant to implementation and grouped constructs from these theories into domains. The collaboration aimed to provide a comprehensive, theory-informed approach to identify determinants of behaviour. The first version was published in 2005, and a subsequent version following a validation exercise was published in 2012. This guide offers practical guidance for those who wish to apply the TDF to assess implementation problems and support intervention design. It presents a brief rationale for using a theoretical approach to investigate and address implementation problems, summarises the TDF and its development, and describes how to apply the TDF to achieve implementation objectives. Examples from the implementation research literature are presented to illustrate relevant methods and practical considerations. Researchers from Canada, the UK and Australia attended a 3-day meeting in December 2012 to build an international collaboration among researchers and decision-makers interested in the advancing use of the TDF. The participants were experienced in using the TDF to assess implementation problems, design interventions, and/or understand change processes. This guide is an output of the meeting and also draws on the authors' collective experience. Examples from the implementation research literature judged by authors to be representative of specific applications of the TDF are included in this guide. We explain and illustrate methods, with a focus on qualitative approaches, for selecting and specifying target behaviours key to implementation, selecting the study design, deciding the sampling strategy, developing study materials, collecting and analysing data, and reporting findings of TDF-based studies. Areas for development include methods for triangulating data, e.g. from interviews, questionnaires and observation and methods for designing interventions based on TDF-based problem analysis. We offer this guide to the implementation community to assist in the application of the TDF to achieve implementation objectives. Benefits of using the TDF include the provision of a theoretical basis for implementation studies, good coverage of potential reasons for slow diffusion of evidence into practice and a method for progressing from theory-based investigation to intervention.
An assessment of maintainability of elevator system to improve facilities management knowledge-base
NASA Astrophysics Data System (ADS)
Siti, N. A.; Asmone, A. S.; Chew, M. Y. L.
2018-02-01
Elevator system is a highly specialized machinery that requires technicians that have a wider array of knowledge in maintaining the system to be safe and reliable. While attaining reliable data of elevator malfunction become challenges, this study has filled the gap by gathering the management-maintenance issues and operational defects of elevator system. Forty-three types of operation defects were found and the consequence defects and their possible causes of occurrences were discussed. To respond to the prime challenges of maintaining elevator system provided by the industry players’ perspective, a theoretical framework is established as a recommendation to improve knowledge base of defects in elevator system which comprises good practices, and solutions to rectify each defects found. Hence, this research paper has theoretically improved the knowledge base of maintainability of elevator system and provide meaningful guidelines in practical senses to the industry professionals.
Ho, Shirley S; Lee, Edmund W J; Ng, Kaijie; Leong, Grace S H; Tham, Tiffany H M
2016-09-01
Based on the influence of presumed media influence (IPMI) model as the theoretical framework, this study examines how injunctive norms and personal norms mediate the influence of healthy lifestyle media messages on public intentions to engage in two types of healthy lifestyle behaviors-physical activity and healthy diet. Nationally representative data collected from 1,055 adults in Singapore demonstrate partial support for the key hypotheses that make up the extended IPMI model, highlighting the importance of a norms-based approach in health communication. Our results indicate that perceived media influence on others indirectly shaped public intentions to engage in healthy lifestyle behaviors through personal norms and attitude, providing partial theoretical support for the extended IPMI model. Practical implications for health communicators in designing health campaigns media messages to motivate the public to engage in healthy lifestyle are discussed.
Zhang, Junwen; Yu, Jianjun; Chi, Nan; Chien, Hung-Chang
2014-08-25
We theoretically and experimentally investigate a time-domain digital pre-equalization (DPEQ) scheme for bandwidth-limited optical coherent communication systems, which is based on feedback of channel characteristics from the receiver-side blind and adaptive equalizers, such as least-mean-squares (LMS) algorithm and constant or multi- modulus algorithms (CMA, MMA). Based on the proposed DPEQ scheme, we theoretically and experimentally study its performance in terms of various channel conditions as well as resolutions for channel estimation, such as filtering bandwidth, taps length, and OSNR. Using a high speed 64-GSa/s DAC in cooperation with the proposed DPEQ technique, we successfully synthesized band-limited 40-Gbaud signals in modulation formats of polarization-diversion multiplexed (PDM) quadrature phase shift keying (QPSK), 8-quadrature amplitude modulation (QAM) and 16-QAM, and significant improvement in both back-to-back and transmission BER performances are also demonstrated.
NASA Astrophysics Data System (ADS)
Huang, Y. G.; Wang, L. G.; Lu, Y. L.; Chen, J. R.; Zhang, J. H.
2015-09-01
Based on the two-dimensional elasticity theory, this study established a mechanical model under chordally opposing distributed compressive loads, in order to perfect the theoretical foundation of the flattened Brazilian splitting test used for measuring the indirect tensile strength of rocks. The stress superposition method was used to obtain the approximate analytic solutions of stress components inside the flattened Brazilian disk. These analytic solutions were then verified through a comparison with the numerical results of the finite element method (FEM). Based on the theoretical derivation, this research carried out a contrastive study on the effect of the flattened loading angles on the stress value and stress concentration degree inside the disk. The results showed that the stress concentration degree near the loading point and the ratio of compressive/tensile stress inside the disk dramatically decreased as the flattened loading angle increased, avoiding the crushing failure near-loading point of Brazilian disk specimens. However, only the tensile stress value and the tensile region were slightly reduced with the increase of the flattened loading angle. Furthermore, this study found that the optimal flattened loading angle was 20°-30°; flattened load angles that were too large or too small made it difficult to guarantee the central tensile splitting failure principle of the Brazilian splitting test. According to the Griffith strength failure criterion, the calculative formula of the indirect tensile strength of rocks was derived theoretically. This study obtained a theoretical indirect tensile strength that closely coincided with existing and experimental results. Finally, this paper simulated the fracture evolution process of rocks under different loading angles through the use of the finite element numerical software ANSYS. The modeling results showed that the Flattened Brazilian Splitting Test using the optimal loading angle could guarantee the tensile splitting failure initiated by a central crack.
Digital Sound Encryption with Logistic Map and Number Theoretic Transform
NASA Astrophysics Data System (ADS)
Satria, Yudi; Gabe Rizky, P. H.; Suryadi, MT
2018-03-01
Digital sound security has limits on encrypting in Frequency Domain. Number Theoretic Transform based on field (GF 2521 – 1) improve and solve that problem. The algorithm for this sound encryption is based on combination of Chaos function and Number Theoretic Transform. The Chaos function that used in this paper is Logistic Map. The trials and the simulations are conducted by using 5 different digital sound files data tester in Wave File Extension Format and simulated at least 100 times each. The key stream resulted is random with verified by 15 NIST’s randomness test. The key space formed is very big which more than 10469. The processing speed of algorithm for encryption is slightly affected by Number Theoretic Transform.
Parametric study of closed wet cooling tower thermal performance
NASA Astrophysics Data System (ADS)
Qasim, S. M.; Hayder, M. J.
2017-08-01
The present study involves experimental and theoretical analysis to evaluate the thermal performance of modified Closed Wet Cooling Tower (CWCT). The experimental study includes: design, manufacture and testing prototype of a modified counter flow forced draft CWCT. The modification based on addition packing to the conventional CWCT. A series of experiments was carried out at different operational parameters. In view of energy analysis, the thermal performance parameters of the tower are: cooling range, tower approach, cooling capacity, thermal efficiency, heat and mass transfer coefficients. The theoretical study included develops Artificial Neural Network (ANN) models to predicting various thermal performance parameters of the tower. Utilizing experimental data for training and testing, the models simulated by multi-layer back propagation algorithm for varying all operational parameters stated in experimental test.
Bolometric Luminosities of Peculiar Type II-P Supernovae: Observational and Theoretical Approaches
NASA Astrophysics Data System (ADS)
Lusk, Jeremy Alexander
2018-01-01
In the three decades since the explosion of SN 1987A, only a handful of other supernovae have been detected which are also thought to originate from blue supergiant progenitors. In this study, we use the five best observed of these supernovae (SNe 1998A, 2000cb, 2006V, 2006au, and 2009E) to examine the bolometric properties of the class through observations and theoretical models. Several techniques for taking photometric observations and inferring bolometric luminosities have been used in the literature. Our newly-improved python package SuperBoL implements many of these techniques. The challenge remains that the true bolometric luminosity of the supernova cannot be directly observed. We must turn to theoretical models in order to examine the validity of the different observationally-based techniques. In this work, we make use of the NLTE generalized atmosphere code PHOENIX to produce synthetic spectra of known luminosity which match the observed supernova spectra. Synthetic photometry of these models is then used as input to SuperBoL to test the different observationally-based bolometric luminosity techniques.
NASA Astrophysics Data System (ADS)
Chen, Xianfeng; Lin, Zhongqin; Yu, Zhongqi; Chen, Xinping; Li, Shuhui
2011-08-01
This study establishes the forming limit diagram (FLD) for QSTE340 seamed tube hydroforming by finite element method (FEM) simulation. FLD is commonly obtained from experiment, theoretical calculation and FEM simulation. But for tube hydroforming, both of the experimental and theoretical means are restricted in the application due to the equipment costs and the lack of authoritative theoretical knowledge. In this paper, a novel approach of predicting forming limit using thickness gradient criterion (TGC) is presented for seamed tube hydroforming. Firstly, tube bulge tests and uniaxial tensile tests are performed to obtain the stress-strain curve for tube three parts. Then one FE model for a classical tube free hydroforming and another FE model for a novel experimental apparatus by applying the lateral compression force and the internal pressure are constructed. After that, the forming limit strain is calculated based on TGC in the FEM simulation. Good agreement between the simulation and experimental results is indicated. By combining the TGC and FEM, an alternative way of predicting forming limit with enough accuracy and convenience is provided.
Kronewitter, Scott R; An, Hyun Joo; de Leoz, Maria Lorna; Lebrilla, Carlito B; Miyamoto, Suzanne; Leiserowitz, Gary S
2009-06-01
Annotation of the human serum N-linked glycome is a formidable challenge but is necessary for disease marker discovery. A new theoretical glycan library was constructed and proposed to provide all possible glycan compositions in serum. It was developed based on established glycobiology and retrosynthetic state-transition networks. We find that at least 331 compositions are possible in the serum N-linked glycome. By pairing the theoretical glycan mass library with a high mass accuracy and high-resolution MS, human serum glycans were effectively profiled. Correct isotopic envelope deconvolution to monoisotopic masses and the high mass accuracy instruments drastically reduced the amount of false composition assignments. The high throughput capacity enabled by this library permitted the rapid glycan profiling of large control populations. With the use of the library, a human serum glycan mass profile was developed from 46 healthy individuals. This paper presents a theoretical N-linked glycan mass library that was used for accurate high-throughput human serum glycan profiling. Rapid methods for evaluating a patient's glycome are instrumental for studying glycan-based markers.
Lung Cancer Screening Participation: Developing a Conceptual Model to Guide Research
Carter-Harris, Lisa; Davis, Lorie L.; Rawl, Susan M.
2017-01-01
Purpose To describe the development of a conceptual model to guide research focused on lung cancer screening participation from the perspective of the individual in the decision-making process. Methods Based on a comprehensive review of empirical and theoretical literature, a conceptual model was developed linking key psychological variables (stigma, medical mistrust, fatalism, worry, and fear) to the health belief model and precaution adoption process model. Results Proposed model concepts have been examined in prior research of either lung or other cancer screening behavior. To date, a few studies have explored a limited number of variables that influence screening behavior in lung cancer specifically. Therefore, relationships among concepts in the model have been proposed and future research directions presented. Conclusion This proposed model is an initial step to support theoretically based research. As lung cancer screening becomes more widely implemented, it is critical to theoretically guide research to understand variables that may be associated with lung cancer screening participation. Findings from future research guided by the proposed conceptual model can be used to refine the model and inform tailored intervention development. PMID:28304262
Lung Cancer Screening Participation: Developing a Conceptual Model to Guide Research.
Carter-Harris, Lisa; Davis, Lorie L; Rawl, Susan M
2016-11-01
To describe the development of a conceptual model to guide research focused on lung cancer screening participation from the perspective of the individual in the decision-making process. Based on a comprehensive review of empirical and theoretical literature, a conceptual model was developed linking key psychological variables (stigma, medical mistrust, fatalism, worry, and fear) to the health belief model and precaution adoption process model. Proposed model concepts have been examined in prior research of either lung or other cancer screening behavior. To date, a few studies have explored a limited number of variables that influence screening behavior in lung cancer specifically. Therefore, relationships among concepts in the model have been proposed and future research directions presented. This proposed model is an initial step to support theoretically based research. As lung cancer screening becomes more widely implemented, it is critical to theoretically guide research to understand variables that may be associated with lung cancer screening participation. Findings from future research guided by the proposed conceptual model can be used to refine the model and inform tailored intervention development.
Theoretical Effects of Substituting Butter with Margarine on Risk of Cardiovascular Disease.
Liu, Qing; Rossouw, Jacques E; Roberts, Mary B; Liu, Simin; Johnson, Karen C; Shikany, James M; Manson, JoAnn E; Tinker, Lesley F; Eaton, Charles B
2017-01-01
Several recent articles have called into question the deleterious effects of high animal fat diets due to mixed results from epidemiologic studies and the lack of clinical trial evidence in meta-analyses of dietary intervention trials. We were interested in examining the theoretical effects of substituting plant-based fats from different types of margarine for animal-based fat from butter on the risk of atherosclerosis-related cardiovascular disease (CVD). We prospectively studied 71,410 women, aged 50-79 years, and evaluated their risk for clinical myocardial infarction (MI), total coronary heart disease (CHD), ischemic stroke, and atherosclerosis-related CVD with an average of 13.2 years of follow-up. Butter and margarine intakes were obtained at baseline and year 3 by means of a validated food frequency questionnaire. Cox proportional hazards regression using a cumulative average diet method was used to estimate the theoretical effect of substituting 1 teaspoon/day of three types of margarine for the same amount of butter. Substituting butter or stick margarine with tub margarine was associated with lower risk of MI (HRs = 0.95 and 0.91). Subgroup analyses, which evaluated these substitutions among participants with a single source of spreadable fat, showed stronger associations for MI (HRs = 0.92 and 0.87). Outcomes of total CHD, ischemic stroke, and atherosclerosis-related CVD showed wide confidence intervals but the same trends as the MI results. This theoretical dietary substitution analysis suggests that substituting butter and stick margarine with tub margarine when spreadable fats are eaten may be associated with reduced risk of myocardial infarction.
Theoretical effects of substituting butter with margarine on risk of cardiovascular disease
Liu, Qing; Rossouw, Jacques E.; Roberts, Mary B.; Liu, Simin; Johnson, Karen C.; Shikany, James M.; Manson, JoAnn E.; Tinker, Lesley F.; Eaton, Charles B.
2017-01-01
Background Several recent papers have called into question the deleterious effects of high animal fat diets due to mixed results from epidemiologic studies and the lack of clinical trial evidence in meta-analyses of dietary intervention trials. We were interested in examining the theoretical effects of substituting plant-based fats from different types of margarine for animal based fat from butter on the risk of atherosclerosis-related cardiovascular disease (CVD). Methods We prospectively studied 71,410 women, aged 50–79 years, and evaluated their risk for clinical myocardial infarction (MI), total coronary heart disease (CHD), ischemic stroke and atherosclerosis-related CVD with an average of 13.2 years of follow-up. Butter and margarine intakes were obtained at baseline and Year 3 by means of a validated food frequency questionnaire. Cox proportional hazards regression using a cumulative average diet method was used to estimate the theoretical effect of substituting 1 teaspoon/day of three types of margarine for the same amount of butter. Results Substituting butter or stick margarine with tub margarine was associated with lower risk of MI (HRs=0.95 and 0.91). Subgroup analyses, which evaluated these substitutions among participants with a single source of spreadable fat, showed stronger associations for MI (HRs=0.92 and 0.87). Outcomes of total CHD, ischemic stroke, and atherosclerosis-related CVD showed wide confidence intervals but the same trends as the MI results. Conclusions This theoretical dietary substitution analysis suggests that substituting butter and stick margarine with tub margarine when spreadable fats are eaten may be associated with reduced risk of myocardial infarction. PMID:27648593
Farrell, Tracy L; Poquet, Laure; Dew, Tristan P; Barber, Stuart; Williamson, Gary
2012-02-01
There is a considerable need to rationalize the membrane permeability and mechanism of transport for potential nutraceuticals. The aim of this investigation was to develop a theoretical permeability equation, based on a reported descriptive absorption model, enabling calculation of the transcellular component of absorption across Caco-2 monolayers. Published data for Caco-2 permeability of 30 drugs transported by the transcellular route were correlated with the descriptors 1-octanol/water distribution coefficient (log D, pH 7.4) and size, based on molecular mass. Nonlinear regression analysis was used to derive a set of model parameters a', β', and b' with an integrated molecular mass function. The new theoretical transcellular permeability (TTP) model obtained a good fit of the published data (R² = 0.93) and predicted reasonably well (R² = 0.86) the experimental apparent permeability coefficient (P(app)) for nine non-training set compounds reportedly transported by the transcellular route. For the first time, the TTP model was used to predict the absorption characteristics of six phenolic acids, and this original investigation was supported by in vitro Caco-2 cell mechanistic studies, which suggested that deviation of the P(app) value from the predicted transcellular permeability (P(app)(trans)) may be attributed to involvement of active uptake, efflux transporters, or paracellular flux.
Gucciardi, Daniel F; Jackson, Ben
2015-01-01
Fostering individuals' long-term participation in activities that promote positive development such as organised sport is an important agenda for research and practice. We integrated the theories of planned behaviour (TPB) and basic psychological needs (BPN) to identify factors associated with young adults' continuation in organised sport over a 12-month period. Prospective study, including an online psycho-social assessment at Time 1 and an assessment of continuation in sport approximately 12 months later. Participants (N=292) aged between 17 and 21 years (M=18.03; SD=1.29) completed an online survey assessing the theories of planned behaviour and basic psychological needs constructs. Bayesian structural equation modelling (BSEM) was employed to test the hypothesised theoretical sequence, using informative priors for structural relations based on empirical and theoretical expectations. The analyses revealed support for the robustness of the hypothesised theoretical model in terms of the pattern of relations as well as the direction and strength of associations among the constructs derived from quantitative summaries of existing research and theoretical expectations. The satisfaction of basic psychological needs was associated with more positive attitudes, higher levels of perceived behavioural control, and more favourable subjective norms; positive attitudes and perceived behavioural control were associated with higher behavioural intentions; and both intentions and perceived behavioural control predicted sport continuation. This study demonstrated the utility of Bayesian structural equation modelling for testing the robustness of an integrated theoretical model, which is informed by empirical evidence from meta-analyses and theoretical expectations, for understanding sport continuation. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.
On the physical basis of a theory of human thermoregulation.
NASA Technical Reports Server (NTRS)
Iberall, A. S.; Schindler, A. M.
1973-01-01
Theoretical study of the physical factors which are responsible for thermoregulation in nude resting humans in a physical steady state. The behavior of oxidative metabolism, evaporative and convective thermal fluxes, fluid heat transfer, internal and surface temperatures, and evaporative phase transitions is studied by physiological/physical modeling techniques. The modeling is based on the theories that the body has a vital core with autothermoregulation, that the vital core contracts longitudinally, that the temperature of peripheral regions and extremities decreases towards the ambient, and that a significant portion of the evaporative heat may be lost underneath the skin. A theoretical basis is derived for a consistent modeling of steady-state thermoregulation on the basis of these theories.
Wireless Networks under a Backoff Attack: A Game Theoretical Perspective.
Parras, Juan; Zazo, Santiago
2018-01-30
We study a wireless sensor network using CSMA/CA in the MAC layer under a backoff attack: some of the sensors of the network are malicious and deviate from the defined contention mechanism. We use Bianchi's network model to study the impact of the malicious sensors on the total network throughput, showing that it causes the throughput to be unfairly distributed among sensors. We model this conflict using game theory tools, where each sensor is a player. We obtain analytical solutions and propose an algorithm, based on Regret Matching, to learn the equilibrium of the game with an arbitrary number of players. Our approach is validated via simulations, showing that our theoretical predictions adjust to reality.
Jack, Leonard; Liburd, Leandris; Spencer, Tirzah; Airhihenbuwa, Collins O
2004-06-01
Eight studies included in a recent systematic review of the efficacy of diabetes self-management education were qualitatively reexamined to determine the presence of theoretical frameworks, methods used to ensure cultural appropriateness, and the quality of the instrument. Theoretical frameworks that help to explain complex pathways that produce health outcomes were lacking; culture indices were not incorporated into diabetes self-management education; and the instruments used to measure outcomes were inadequate. We provide recommendations to improve research on diabetes self-management education in community settings through use of a contextual framework that encourages targeting multiple levels of influence--individual, family, organizational, community, and policy.
NASA Astrophysics Data System (ADS)
Sun, Ligang; He, Xiaoqiao; Lu, Jian
2018-02-01
The recent studies on nanotwinned (NT) and hierarchical nanotwinned (HNT) face-centered cubic (FCC) metals are presented in this review. The HNT structures have been supposed as a kind of novel structure to bring about higher strength/ductility than NT counterparts in crystalline materials. We primarily focus on the recent developments of the experimental, atomistic and theoretical studies on the NT and HNT structures in the metallic materials. Some advanced bottom-up and top-down techniques for the fabrication of NT and HNT structures are introduced. The deformation induced HNT structures are available by virtue of severe plastic deformation (SPD) based techniques while the synthesis of growth HNT structures is so far almost unavailable. In addition, some representative molecular dynamics (MD) studies on the NT and HNT FCC metals unveil that the nanoscale effects such as twin spacing, grain size and plastic anisotropy greatly alter the performance of NT and HNT metals. The HNT structures may initiate unique phenomena in comparison with the NT ones. Furthermore, based on the phenomena and mechanisms revealed by experimental and MD simulation observations, a series of theoretical models have been proposed. They are effective to describe the mechanical behaviors of NT and HNT metals within the applicable scope. So far the development of manufacturing technologies of HNT structures, as well as the studies on the effects of HNT structures on the properties of metals are still in its infancy. Further exploration is required to promote the design of advanced materials.
Creative Expression as a Way of Knowing in Diabetes Adult Health Education: An Action Research Study
ERIC Educational Resources Information Center
Stuckey, Heather L.
2009-01-01
This action research study explores the meaning-making process using forms of creative expression for eight women with insulin-dependent diabetes. The study is theoretically informed by arts-based ways of knowing and aspects of feminist poststructuralism, and explains the process of creativity used in the action research process. The findings…
ERIC Educational Resources Information Center
Carmichael, Colin; MacDonald, Amy; McFarland-Piazza, Laura
2014-01-01
This article is based on an exploratory study that examines factors which predict children's performance on the numeracy component of the Australian National Assessment Program--Literacy and Numeracy (NAPLAN). Utilizing an ecological theoretical model, this study examines child, home and school variables which may enable or constrain NAPLAN…
Using Illustrations to Depict Preservice Science Teachers' Self-Efficacy: A Case Study
ERIC Educational Resources Information Center
Greco, Robert Del; Bernadowski, Carianne; Parker, Susan
2018-01-01
This qualitative case study conducted at a small private university in the U.S. found that preservice teacher self-efficacy increased over the course of four semesters when taught inquiry-based instruction from a Social Constructivist Theoretical framework. This study utilized "A Draw a Science Teacher Test Checklist (DASTT-C)" created…
Teacher Self-Efficacy and Occupational Stress: A Major Australian Curriculum Reform Revisited
ERIC Educational Resources Information Center
McCormick, John; Ayres, Paul L.
2009-01-01
Purpose: The purpose of this research was to study teachers' self-efficacy and occupational stress in the context of a large-scale curriculum reform in New South Wales, Australia. The study aims to follow up and replicate a study carried out approximately one year earlier. Design/methodology/approach: A theoretical framework, primarily based on…
ERIC Educational Resources Information Center
Bradizza, Clara M.; Maisto, Stephen A.; Vincent, Paula C.; Stasiewicz, Paul R.; Connors, Gerard J.; Mercer, Nicole D.
2009-01-01
Few investigators studying alcohol abuse among individuals with a severe mental illness (SMI) have examined predictors of posttreatment alcohol outcomes. In the present study, a multivariate approach based on a theoretical model was used to study the relationship between psychosocial factors and post-treatment-initiation alcohol use. Predictors of…
Factors Affecting Adoption of Facebook: An Exploratory Study of the LIS Community Perspective
ERIC Educational Resources Information Center
Aharony, Noa
2014-01-01
This study seeks to investigate whether information professionals, as well as LIS students, are ready to assimilate Facebook in their work and educational environments. The study uses the Technology Acceptance Model (TAM) as well as some characteristics of the "Big Five" model of personality as a theoretical base from which to predict…
College Students' Attention Behaviors during Independent Study and Course Level Academic Performance
ERIC Educational Resources Information Center
Wagner, Linda G.
2012-01-01
Students in college make daily choices about how to use their independent study time, including choices about allocation of attention. Based on theoretical considerations and clinical studies, attention and the dividing of attention through multitasking is thought to have a relationship to performance levels. Research is only beginning to explore,…
ERIC Educational Resources Information Center
Kim, Jongyoung
2012-01-01
This study analyzes the learning and cultural experiences of Korean graduate students in the United States. Based on 50 qualitative interviews, the study focuses on how global knowledge and the power relations of language determine their education in a transnational system. At a theoretical level, the study criticizes both the functionalist…
Responsiveness and Renewal in Canada's Community Colleges: A Study of Change in Organizations.
ERIC Educational Resources Information Center
Levin, John S.; Dennison, John D.
In 1988, a study was conducted to determine whether and to what extent the principles of opportunity, accessibility, adaptability, and comprehensiveness upon which Canada's community colleges were established have survived into the 1980's. The theoretical model underpinning the study was based on a three-dimensional matrix in which theories of…
The functions of hospital-based home care for people with severe mental illness in Taiwan.
Huang, Xuan-Yi; Lin, Mei-Jue; Yang, Tuz-Ching; Hsu, Yuan-Shan
2010-02-01
The purposes of this study were to understand the functions of hospital-based home care for people with severe mental illness in Taiwan, and the factors that affect functions of professionals who provide hospital-based home care. Hospital-based home care is a service which provides those people with serious mental illnesses who are in crisis and who are candidates for admission to hospital. Home care has been shown to have several advantages over inpatient treatment. However, there is a lack of knowledge about the functions of hospital-based home care for people with severe mental illness in Taiwan. This qualitative study was based on the grounded theory method of Strauss and Corbin. The study was conducted in six different hospital areas in central Taiwan in 2007-2008. Data were collected using semi-structured face-to-face interviews. Constant comparative analysis continued during the open, axial and selective coding processes until data saturation occurred. Participants were selected by theoretical sampling. When theoretical saturation was achieved, 21 clients with mental illness, 19 carers and 25 professionals were interviewed. Several functions were found when these professionals provided hospital-based home care services for people with severe mental illness in Taiwan, including stabilising the clients illness, supplying emergency care services, improving life-coping abilities, employment and welfare assistance, emotional support for both clients and carers, assistance with future and long-term arrangements and assistance with communication between carers and clients. Hospital-based home care provides several important services for helping clients and their families to live in the community. The recommendations based on the findings of this study can be used as a guide to improve the delivery of hospital-based home care services to community-dwelling clients with severe mental illness and their carers.
Tube Bulge Process : Theoretical Analysis and Finite Element Simulations
NASA Astrophysics Data System (ADS)
Velasco, Raphael; Boudeau, Nathalie
2007-05-01
This paper is focused on the determination of mechanics characteristics for tubular materials, using tube bulge process. A comparative study is made between two different models: theoretical model and finite element analysis. The theoretical model is completely developed, based first on a geometrical analysis of the tube profile during bulging, which is assumed to strain in arc of circles. Strain and stress analysis complete the theoretical model, which allows to evaluate tube thickness and state of stress, at any point of the free bulge region. Free bulging of a 304L stainless steel is simulated using Ls-Dyna 970. To validate FE simulations approach, a comparison between theoretical and finite elements models is led on several parameters such as: thickness variation at the free bulge region pole with bulge height, tube thickness variation with z axial coordinate, and von Mises stress variation with plastic strain. Finally, the influence of geometrical parameters deviations on flow stress curve is observed using analytical model: deviations of the tube outer diameter, its initial thickness and the bulge height measurement are taken into account to obtain a resulting error on plastic strain and von Mises stress.
Child Maltreatment in the "Children of the Nineties": A Cohort Study of Risk Factors
ERIC Educational Resources Information Center
Sidebotham, Peter; Heron, Jon
2006-01-01
Aim: To analyze the multiple factors affecting the risk of maltreatment in young children within a comprehensive theoretical framework. Methods: The research is based on a large UK cohort study, the Avon Longitudinal Study of Parents and Children. Out of 14,256 children participating in the study, 293 were investigated by social services for…
ERIC Educational Resources Information Center
Carroll, D.
2005-01-01
This article reports on a year-long study of collaborative professional learning in a mentor teacher study group connected to a large university teacher education program. It introduces a theoretical framework for considering the nature of interactive talk and its relationship to professional learning. Using examples of study group discourse, it…
Content Based Image Retrieval and Information Theory: A General Approach.
ERIC Educational Resources Information Center
Zachary, John; Iyengar, S. S.; Barhen, Jacob
2001-01-01
Proposes an alternative real valued representation of color based on the information theoretic concept of entropy. A theoretical presentation of image entropy is accompanied by a practical description of the merits and limitations of image entropy compared to color histograms. Results suggest that image entropy is a promising approach to image…
An Activity and Theory for Applying Human Systems Approach to Industrial Arts.
ERIC Educational Resources Information Center
Mietus, Walter S.
A human systems approach that emphasizes knowing the parts of a phenomenon, their order, and particularly their interactions needs to be adopted by industrial arts. A student-based theoretical framework that incorporates systems and subsystems in industrial arts has been presented by Donald Maley. The theoretical base includes 10 organismic…
Dimensions of vegetable parenting practices among preschoolers
USDA-ARS?s Scientific Manuscript database
The objective of this study was to determine the factor structure of 31 effective and ineffective vegetable parenting practices used by parents of preschool children based on three theoretically proposed factors: responsiveness, control, and structure. The methods employed included both corrected it...
Computer program determines chemical equilibria in complex systems
NASA Technical Reports Server (NTRS)
Gordon, S.; Zeleznik, F. J.
1966-01-01
Computer program numerically solves nonlinear algebraic equations for chemical equilibrium based on iteration equations independent of choice of components. This program calculates theoretical performance for frozen and equilibrium composition during expansion and Chapman-Jouguet flame properties, studies combustion, and designs hardware.
[Compulsive masturbation in the child].
Pedreira Massa, J L; Sastre, S H; Mendoza Berjano, E
1983-03-01
Onanism is approached on a theoretical base. Evolutive and pathological significance is also studied. Characteristics of children, family and children attitudes, personality structure, onanism pattern on children and parents fantasies are observed. The importance of affection demand and a permissive therapy is emphasized.
Life-Game, with Glass Beads and Molecules, on the Principles of the Origin of Life
ERIC Educational Resources Information Center
Eigen, Manfred; Haglund, Herman
1976-01-01
Discusses a theoretical model that uses a game as a base for studying processes of a stochastic nature, which involve chemical reactions, molecular systems, biological processes, cells, or people in a population. (MLH)
Klafke, Nadja; Mahler, Cornelia; von Hagens, Cornelia; Blaser, Gisela; Bentner, Martina; Joos, Stefanie
2016-05-01
The purpose of this study was to develop a complex nursing intervention including complementary and alternative medicine (CAM) for breast and gynecologic cancer patients during chemotherapy to improve quality of life. Data sources Theoretical framework and concepts, practical nursing knowledge, and evidence-based studies were compiled in interprofessional meetings. Data synthesis The final complex intervention consists of three autonomous, but interacting components: (1) CAM nursing package, (2) resource-oriented counseling, and (3) evidence-based information material on CAM. CAM interventions include acupressure, aromatherapy, compress, and massage, targeting 14 clinically relevant symptoms during chemotherapy. Participants receive these interventions during chemotherapy with instructions for self care. During a counseling interview, the patient's needs and preferences are assessed by trained nurses. Furthermore, participants are equipped with evidence-based information material (booklet and DVD). Prior to study start, nurses attended training modules for administering CAM therapies and for communicating and counseling within the salutogenic approach. It was possible to design a multimodal CAM nursing intervention based on a theoretical concept, evidence-based studies, and practical nursing experience targeting the prevention or relief of side-effects women suffer during chemotherapy. The systematic analysis of the CONGO study will contribute to evidence-based CAM nursing care within supportive cancer care. Oncology nurses play an important role in supportive CAM care of breast and gynecologic cancer patients in daily clinical practice. Within oncology outpatient services, the implementation of evidence-based CAM nursing interventions and counseling may contribute to understand the impact of nursing on patient quality of life and symptom relief. This can lead to a new understanding of the nurse's professional role.
Study preferences for exemplar variability in self-regulated category learning.
Wahlheim, Christopher N; DeSoto, K Andrew
2017-02-01
Increasing exemplar variability during category learning can enhance classification of novel exemplars from studied categories. Four experiments examined whether participants preferred variability when making study choices with the goal of later classifying novel exemplars. In Experiments 1-3, participants were familiarised with exemplars of birds from multiple categories prior to making category-level assessments of learning and subsequent choices about whether to receive more variability or repetitions of exemplars during study. After study, participants classified novel exemplars from studied categories. The majority of participants showed a consistent preference for variability in their study, but choices were not related to category-level assessments of learning. Experiment 4 provided evidence that study preferences were based primarily on theoretical beliefs in that most participants indicated a preference for variability on questionnaires that did not include prior experience with exemplars. Potential directions for theoretical development and applications to education are discussed.
LOCHER, JULIE L.; BALES, CONNIE W.; ELLIS, AMY C.; LAWRENCE, JEANNINE C.; NEWTON, LAURA; RITCHIE, CHRISTINE S.; ROTH, DAVID L.; BUYS, DAVID L.; VICKERS, KRISTIN S.
2012-01-01
We conducted a study designed to evaluate the efficacy and feasibility of a multilevel self-management intervention to improve nutritional intake in a group of older adults receiving Medicare home health services who were at especially high risk for experiencing undernutrition. The Behavioral Nutrition Intervention for Community Elders (B-NICE) trial used a prospective randomized controlled design to determine whether individually tailored counseling focused on social and behavioral aspects of eating resulted in increased caloric intake and improved nutrition-related health outcomes in a high-risk population of older adults. The study was guided by the theoretical approaches of the Ecological Model and Social Cognitive Theory. The development and implementation of the B-NICE protocol, including the theoretical framework, methodology, specific elements of the behavioral intervention, and assurances of the treatment fidelity, as well as the health policy implications of the trial results, are presented in this article. PMID:22098180
Surface Segregation in Multicomponent Systems: Modeling of Surface Alloys and Alloy Surfaces
NASA Technical Reports Server (NTRS)
Bozzolo, Guillermo; Ferrante, John; Noebe, Ronald D.; Good, Brian; Honecy, Frank S.; Abel, Phillip
1999-01-01
The study of surface segregation, although of great technological importance, has been largely restricted to experimental work due to limitations associated with theoretical methods. However, recent improvements in both first-particle and semi-empirical methods are opening, the doors to an array of new possibilities for surface scientists. We apply one of these techniques, the Bozzolo, Ferrante and Smith (BFS) method for alloys, which is particularly suitable for complex systems, to several aspects of the computational modeling of surfaces and segregation, including alloy surface segregation, structure and composition of alloy surfaces, and the formation of surface alloys. We conclude with the study of complex NiAl-based binary, ternary and quaternary thin films (with Ti, Cr and Cu additions to NiAl). Differences and similarities between bulk and surface compositions are discussed, illustrated by the results of Monte Carlo simulations. For some binary and ternary cases, the theoretical predictions are compared to experimental results, highlighting the accuracy and value of this developing theoretical tool.
Excess capacity: markets regulation, and values.
Madden, C W
1999-01-01
OBJECTIVE: To examine the conceptual bases for the conflicting views of excess capacity in healthcare markets and their application in the context of today's turbulent environment. STUDY SETTING: The policy and research literature of the past three decades. STUDY DESIGN: The theoretical perspectives of alternative economic schools of thought are used to support different policy positions with regard to excess capacity. Changes in these policy positions over time are linked to changes in the economic and political environment of the period. The social values implied by this history are articulated. DATA COLLECTION: Standard library search procedures are used to identify relevant literature. PRINCIPAL FINDINGS: Alternative policy views of excess capacity in healthcare markets rely on differing theoretical foundations. Changes in the context in which policy decisions are made over time affect the dominant theoretical framework and, therefore, the dominant policy view of excess capacity. CONCLUSIONS: In the 1990s, multiple perspectives of optimal capacity still exist. However, our evolving history suggests a set of persistent values that should guide future policy in this area. PMID:10029502
NASA Astrophysics Data System (ADS)
Li, Jun; Xia, Qing; Wang, Xiaofa
2017-10-01
Based on the extended spin-flip model, the all-optical flip-flop stability maps of the 1550nm vertical-cavity surface-emitting laser have been studied. Theoretical results show that excellent agreement is found between theoretical and the reported experimental results in polarization switching point current which is equal to 1.95 times threshold. Furthermore, the polarization bistable region is wide which is from 1.05 to 1.95 times threshold. A new method is presented that uses power difference between two linear polarization modes as the judging criterion of trigger degree and stability maps of all-optical flip-flop operation under different injection parameters are obtained. By alternately injecting set and reset pulse with appropriate parameters, the mutual conversion switching between two polarization modes is realized, the feasibility of all-optical flip-flop operation is checked theoretically. The results show certain guiding significance on the experimental study on all optical buffer technology.
NASA Astrophysics Data System (ADS)
Keshavarz, Samara; Kontos, Sofia; Wardecki, Dariusz; Kvashnin, Yaroslav O.; Pereiro, Manuel; Panda, Swarup K.; Sanyal, Biplab; Eriksson, Olle; Grins, Jekabs; Svensson, Gunnar; Gunnarsson, Klas; Svedlindh, Peter
2018-04-01
We present a comprehensive study of the magnetic properties of Sr3 -xYx(Fe1.25Ni0.75) O7 -δ (0 ≤x ≤0.75 ). Experimentally, the magnetic properties are investigated using superconducting quantum interference device (SQUID) magnetometry and neutron powder diffraction (NPD). This is complemented by a theoretical study based on density functional theory as well as the Heisenberg exchange parameters. Experimental results show an increase in the Néel temperature (TN) with an increase of Y concentrations and O occupancy. The NPD data reveal that all samples are antiferromagnetically ordered at low temperatures, which has been confirmed by our theoretical simulations for the selected samples. Our first-principles calculations suggest that the three-dimensional magnetic order is stabilized due to finite interlayer exchange couplings. The latter give rise to finite interlayer spin-spin correlations, which disappear above TN.
Dynamics of the brain: Mathematical models and non-invasive experimental studies
NASA Astrophysics Data System (ADS)
Toronov, V.; Myllylä, T.; Kiviniemi, V.; Tuchin, V. V.
2013-10-01
Dynamics is an essential aspect of the brain function. In this article we review theoretical models of neural and haemodynamic processes in the human brain and experimental non-invasive techniques developed to study brain functions and to measure dynamic characteristics, such as neurodynamics, neurovascular coupling, haemodynamic changes due to brain activity and autoregulation, and cerebral metabolic rate of oxygen. We focus on emerging theoretical biophysical models and experimental functional neuroimaging results, obtained mostly by functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS). We also included our current results on the effects of blood pressure variations on cerebral haemodynamics and simultaneous measurements of fast processes in the brain by near-infrared spectroscopy and a very novel functional MRI technique called magnetic resonance encephalography. Based on a rapid progress in theoretical and experimental techniques and due to the growing computational capacities and combined use of rapidly improving and emerging neuroimaging techniques we anticipate during next decade great achievements in the overall knowledge of the human brain.
Designing a Double-Pole Nanoscale Relay Based on a Carbon Nanotube: A Theoretical Study
NASA Astrophysics Data System (ADS)
Mu, Weihua; Ou-Yang, Zhong-can; Dresselhaus, Mildred S.
2017-08-01
We theoretically investigate a novel and powerful double-pole nanoscale relay based on a carbon nanotube, which is one of the nanoelectromechanical switches being able to work under the strong nuclear radiation, and analyze the physical mechanism of the operating stages in the operation, including "pull in," "connection," and "pull back," as well as the key factors influencing the efficiency of the devices. We explicitly provide the analytical expression of the two important operation voltages, Vpull in and Vpull back , therefore clearly showing the dependence of the material properties and geometry of the present devices by the analytical method from basic physics, avoiding complex numerical calculations. Our method is easy to use in preparing the design guide for fabricating the present device and other nanoelectromechanical devices.
TIE: an ability test of emotional intelligence.
Śmieja, Magdalena; Orzechowski, Jarosław; Stolarski, Maciej S
2014-01-01
The Test of Emotional Intelligence (TIE) is a new ability scale based on a theoretical model that defines emotional intelligence as a set of skills responsible for the processing of emotion-relevant information. Participants are provided with descriptions of emotional problems, and asked to indicate which emotion is most probable in a given situation, or to suggest the most appropriate action. Scoring is based on the judgments of experts: professional psychotherapists, trainers, and HR specialists. The validation study showed that the TIE is a reliable and valid test, suitable for both scientific research and individual assessment. Its internal consistency measures were as high as .88. In line with theoretical model of emotional intelligence, the results of the TIE shared about 10% of common variance with a general intelligence test, and were independent of major personality dimensions.
Models for 31-Mode PVDF Energy Harvester for Wearable Applications
Zhao, Jingjing; You, Zheng
2014-01-01
Currently, wearable electronics are increasingly widely used, leading to an increasing need of portable power supply. As a clean and renewable power source, piezoelectric energy harvester can transfer mechanical energy into electric energy directly, and the energy harvester based on polyvinylidene difluoride (PVDF) operating in 31-mode is appropriate to harvest energy from human motion. This paper established a series of theoretical models to predict the performance of 31-mode PVDF energy harvester. Among them, the energy storage one can predict the collected energy accurately during the operation of the harvester. Based on theoretical study and experiments investigation, two approaches to improve the energy harvesting performance have been found. Furthermore, experiment results demonstrate the high accuracies of the models, which are better than 95%. PMID:25114981
Job stress and cardiovascular disease: a theoretic critical review.
Kristensen, T S
1996-07-01
During the last 15 years, the research on job stress and cardiovascular diseases has been dominated by the job strain model developed by R. Karasek (1979) and colleagues (R. Karasek & T. Theorell, 1990). In this article the results of this research are briefly summarized, and the theoretical and methodological basis is discussed and criticized. A sociological interpretation of the model emphasizing theories of technological change, qualifications of the workers, and the organization of work is proposed. Furthermore, improvements with regard to measuring the job strain dimensions and to sampling the study base are suggested. Substantial improvements of the job strain research could be achieved if the principle of triangulation were used in the measurements of stressors, stress, and sickness and if occupation-based samples were used instead of large representative samples.
A theoretical examination of the rights of nurses.
Kangasniemi, Mari; Viitalähde, Kirsi; Porkka, Sanna
2010-09-01
Nurses' duties and patients' rights have been important foci in nursing. Nurses' rights legitimate the power and responsibility of the profession. There are few published articles on this subject in the nursing science literature. This article is a theoretical examination of nurses' rights that aims to structure (i.e. show the internal logic of) those that have been little studied. It is based on the philosophical literature and published research. Nurses' rights can be divided into: human and civil rights, rights based on health care legislation, professional rights, and earned rights. In this context, professional rights relate to nursing and also to tasks shared with other health care professions. Analyzing nurses' rights will help to promote these rights, improve nurses' position both nationally and internationally, and provide possibilities for enhancing patient care.