Empowering leaders optimize working conditions for engagement: a multilevel study.

Science.gov (United States)

Tuckey, Michelle R; Bakker, Arnold B; Dollard, Maureen F

2012-01-01

Using a multilevel framework, this study examined the role of empowering leadership at the group level by fire brigade captains in facilitating the individual level motivational processes that underpin work engagement in volunteer firefighters. Anonymous mail surveys were completed by 540 volunteer firefighters from 68 fire brigades and, separately, by 68 brigade captains. As predicted on the basis of the Job Demands-Resources model, increased levels of cognitive demands and cognitive resources partially mediated the relationship between empowering leadership and work engagement. In a three-way Leadership × Demands × Resources interaction, empowering leadership also had the effect of optimizing working conditions for engagement by strengthening the positive effect of a work context in which both cognitive demands and cognitive resources were high. Our findings shed light on a process through which leaders can empower workers and enhance well-being: via their influence on and interaction with the work environment. They also underscore the need to examine work engagement from a multilevel theoretical perspective.

Examining multi-level effects on corporate social responsibility and irresponsibility

Directory of Open Access Journals (Sweden)

Mazzei Matthew J.

2015-10-01

Full Text Available What influences firms to engage in socially responsible (irresponsible activities? Corporate social responsibility (CSR, the efforts of firms to create a positive and desirable impact on society, and corporate social irresponsibility (CSI, contrary actions of unethical behavior that negatively influence society, have become an important focus of discussion for both corporations and scholars. Despite this interest, our understanding of organizations’ socially responsible (irresponsible actions and their antecedents is still developing. A dearth of knowledge about the multi-level nature of the drivers of CSR and CSI continues to exist. Utilizing a longitudinal sample composed of 899 firms in 66 industries, we follow a prominent model to empirically examine industry-, firm-, and individual-level effects on CSR and CSI. Employing variance decomposition analysis, our results confirm that all three levels of investigation do indeed influence CSR and CSI. More substantively, our analysis estimates the magnitude of the effects attributable to each of the three levels for both CSR and CSI. We also compare multi-level influences on two separate CSR strategies, those targeting primary stakeholders (strategic CSR and those targeting secondary stakeholders (social CSR. We find greater industry- and firmlevel effects on social CSR, and higher individual-level effects on strategic CSR. Our results build on the conceptual work of previous authors by providing empirical analyses to confirm multilevel influences on CSR and extending prior multi-level theory to the concept of CSI. Further, we add to the emerging literature regarding stakeholder demands by examining the various influences on CSR strategies targeting different stakeholder groups.

Economic and Sociological Correlates of Suicides: Multilevel Analysis of the Time Series Data in the United Kingdom.

Science.gov (United States)

Sun, Bruce Qiang; Zhang, Jie

2016-03-01

For the effects of social integration on suicides, there have been different and even contradictive conclusions. In this study, the selected economic and social risks of suicide for different age groups and genders in the United Kingdom were identified and the effects were estimated by the multilevel time series analyses. To our knowledge, there exist no previous studies that estimated a dynamic model of suicides on the time series data together with multilevel analysis and autoregressive distributed lags. The investigation indicated that unemployment rate, inflation rate, and divorce rate are all significantly and positively related to the national suicide rates in the United Kingdom from 1981 to 2011. Furthermore, the suicide rates of almost all groups above 40 years are significantly associated with the risk factors of unemployment and inflation rate, in comparison with the younger groups. © 2016 American Academy of Forensic Sciences.

Multilevel modeling using R

CERN Document Server

Finch, W Holmes; Kelley, Ken

2014-01-01

A powerful tool for analyzing nested designs in a variety of fields, multilevel/hierarchical modeling allows researchers to account for data collected at multiple levels. Multilevel Modeling Using R provides you with a helpful guide to conducting multilevel data modeling using the R software environment.After reviewing standard linear models, the authors present the basics of multilevel models and explain how to fit these models using R. They then show how to employ multilevel modeling with longitudinal data and demonstrate the valuable graphical options in R. The book also describes models fo

Opposition to enlargement as a symbolic defence of group position: multilevel analyses of attitudes toward candidates' entries in the EU-25.

Science.gov (United States)

Dixon, Jeffrey C

2010-03-01

Despite the sociological and geopolitical significance of EU enlargement and opinion toward it, extant literature is lacking a theory of enlargement opinion and an examination of opinion in the wake of the 2004 enlargement. This paper fills these gaps by developing a symbolic defence of group position model to explain opposition to the entries of candidate states (as of 2005: Bulgaria, Romania, Croatia, and Turkey) and to examine how these explanations differ for post-Communist EU members. Results of hierarchical multinomial logistic models of Eurobarometer (European Commission 2005) data from the EU-25 support the notion that the symbolic nature of enlargement shapes the effects of interests, threat, and other factors on opinion depending on candidates' position in a culturally and historically-rooted hierarchy of 'European-ness'. Attitudes toward Turkey's entry are less shaped by material interests than attitudes toward other candidates' entries, which is explained by Turkey's position at the bottom - and post-Communist countries' position in the middle - of this hierarchy in the post-Cold War era. Attitudes toward Turkey's entry are rather a function of the perceived threat that it poses to the group position and identity of Europeans, which is defended by the politically knowledgeable. While the lower levels of threat in post-socialist EU member countries help to account for their lower levels of opposition to candidates' entries, people in these countries to a greater extent use European identity as a way of symbolically distancing themselves from Turkey. Implications are discussed.

Small groups, contexts, and civic engagement: A multilevel analysis of United States Congregational Life Survey data.

Science.gov (United States)

Whitehead, Andrew L; Stroope, Samuel

2015-07-01

Prior research suggests that church-goers are more civically engaged than their non-church-going counterparts. Little is known, however, about how the popular phenomenon of small groups factors into this equation. In the present study, we examine relationships between small group participation at individual and congregation levels and civic engagement. Using multilevel modeling and national data on congregations and individuals from the U.S. Congregational Life Study (n=82,044), we find that: (1) individual-level small group involvement is associated with four measures of civic engagement; (2) congregation-level small group participation is associated with both lower and higher civic engagement in the case of two outcomes; and (3) in the case of three civic outcomes, congregation-level small group participation moderates individual-level small group involvement such that small group members' civic activity more closely resembles the lower civic engagement of small group nonparticipants. In the case of one civic outcome, at high levels of overall small group participation, small group members' civic engagement drops below that of small group nonparticipants. Explanations for these findings, including a "crowding out" effect, are examined including their complex implications for debates regarding small groups, religious involvement, and civic engagement. Copyright © 2014 Elsevier Inc. All rights reserved.

Multi-level predictive maintenance for multi-component systems

International Nuclear Information System (INIS)

Nguyen, Kim-Anh; Do, Phuc; Grall, Antoine

2015-01-01

In this paper, a novel predictive maintenance policy with multi-level decision-making is proposed for multi-component system with complex structure. The main idea is to propose a decision-making process considered on two levels: system level and component one. The goal of the decision rules at the system level is to address if preventive maintenance actions are needed regarding the predictive reliability of the system. At component level the decision rules aim at identifying optimally a group of several components to be preventively maintained when preventive maintenance is trigged due to the system level decision. Selecting optimal components is based on a cost-based group improvement factor taking into account the predictive reliability of the components, the economic dependencies as well as the location of the components in the system. Moreover, a cost model is developed to find the optimal maintenance decision variables. A 14-component system is finally introduced to illustrate the use and the performance of the proposed predictive maintenance policy. Different sensitivity analysis are also investigated and discussed. Indeed, the proposed policy provides more flexibility in maintenance decision-making for complex structure systems, hence leading to significant profits in terms of maintenance cost when compared with existing policies. - Highlights: • A predictive maintenance policy for complex structure systems is proposed. • Multi-level decision process based on prognostic results is proposed. • A cost-based group importance measure is introduced for decision-making. • Both positive and negative dependencies between components are investigated. • A cost model and Monte Carlo simulation are developed for optimization process.

EUROPEAN INTEGRATION: A MULTILEVEL PROCESS THAT REQUIRES A MULTILEVEL STATISTICAL ANALYSIS

Directory of Open Access Journals (Sweden)

Roxana-Otilia-Sonia HRITCU

2015-11-01

Full Text Available A process of market regulation and a system of multi-level governance and several supranational, national and subnational levels of decision making, European integration subscribes to being a multilevel phenomenon. The individual characteristics of citizens, as well as the environment where the integration process takes place, are important. To understand the European integration and its consequences it is important to develop and test multi-level theories that consider individual-level characteristics, as well as the overall context where individuals act and express their characteristics. A central argument of this paper is that support for European integration is influenced by factors operating at different levels. We review and present theories and related research on the use of multilevel analysis in the European area. This paper draws insights on various aspects and consequences of the European integration to take stock of what we know about how and why to use multilevel modeling.

Multilevel and kin selection in a connected world

DEFF Research Database (Denmark)

Wade, Michael J; Wilson, David S; Goodnight, Charles

2010-01-01

in the opposition of two processes: within-group and among-group selection. This distinction is important in light of the current controversy among evolutionary biologists in which some continue to affirm that natural selection centres only and always at the level of the individual organism or gene, despite......Wild et al. argue that the evolution of reduced virulence can be understood from the perspective of inclusive fitness, obviating the need to evoke group selection as a contributing causal factor. Although they acknowledge the mathematical equivalence of the inclusive fitness and multilevel...... selection approaches, they conclude that reduced virulence can be viewed entirely as an individual-level adaptation by the parasite. Here we show that their model is a well-known special case of the more general theory of multilevel selection, and that the cause of reduced virulence resides...

Compact groups of positive operators on Banach lattices

NARCIS (Netherlands)

Jeu, de M.F.E.; Wortel, M.R.

2014-01-01

In this paper, we study groups of positive operators on Banach lattices. If a certain factorization property holds for the elements of such a group, the group has a homomorphic image in the isometric positive operators which has the same invariant ideals as the original group. If the group is

Reflection Positive Stochastic Processes Indexed by Lie Groups

Science.gov (United States)

Jorgensen, Palle E. T.; Neeb, Karl-Hermann; Ólafsson, Gestur

2016-06-01

Reflection positivity originates from one of the Osterwalder-Schrader axioms for constructive quantum field theory. It serves as a bridge between euclidean and relativistic quantum field theory. In mathematics, more specifically, in representation theory, it is related to the Cartan duality of symmetric Lie groups (Lie groups with an involution) and results in a transformation of a unitary representation of a symmetric Lie group to a unitary representation of its Cartan dual. In this article we continue our investigation of representation theoretic aspects of reflection positivity by discussing reflection positive Markov processes indexed by Lie groups, measures on path spaces, and invariant gaussian measures in spaces of distribution vectors. This provides new constructions of reflection positive unitary representations.

Under multilevel selection: "when shall you be neither spiteful nor envious?".

Science.gov (United States)

Garay, József; Csiszár, Villő; Móri, Tamás F

2014-01-07

In this paper, we study the egalitarianism-game in multilevel selection situation. The individuals form reproductive groups. In each group, an egalitarianism-game determines the number of juveniles of different phenotypes (spiteful, envious, neutral and donator). Before the juveniles form the next reproductive group, they have to survive either predators' attacks or a fight between two groups. We adopt the ESS definition of Maynard Smith to multilevel selection. Based on the "group size advantage" assumption (which claims that each juvenile's survival rate depends on the size of his own group, supposing that either the survival rate under predators' attacks is higher in larger groups, or in inter-group aggression usually the larger group wins) we found that when the survival probability has a massive effect on the average fitness, then "group fitness maximizing behavior" (in our case, either neutral or donator) has evolutionary advantage over "competitive behavior" (in our case, either spiteful or envious). © 2013 Elsevier Ltd. All rights reserved.

Conceptualising Multilevel Regulation in the EU: A Legal Translation of Multilevel Governance?

NARCIS (Netherlands)

Chowdhury, Nupur; Wessel, Ramses A.

2012-01-01

How should we conceive of regulation in the European context? This paper attempts to answer this by developing multilevel regulation as a theoretical concept. The basic aim of the paper is to explore the difference and convergence between regulation and governance and develop multilevel governance

Power and type I error of local fit statistics in multilevel latent class analysis

NARCIS (Netherlands)

Nagelkerke, E.; Oberski, D.L.; Vermunt, J.K.

2017-01-01

In the social and behavioral sciences, variables are often categorical and people are often nested in groups. Models for such data, such as multilevel logistic regression or the multilevel latent class model, should account for not only the categorical nature of the variables, but also the nested

Multilevel geometry optimization

Science.gov (United States)

Rodgers, Jocelyn M.; Fast, Patton L.; Truhlar, Donald G.

2000-02-01

Geometry optimization has been carried out for three test molecules using six multilevel electronic structure methods, in particular Gaussian-2, Gaussian-3, multicoefficient G2, multicoefficient G3, and two multicoefficient correlation methods based on correlation-consistent basis sets. In the Gaussian-2 and Gaussian-3 methods, various levels are added and subtracted with unit coefficients, whereas the multicoefficient Gaussian-x methods involve noninteger parameters as coefficients. The multilevel optimizations drop the average error in the geometry (averaged over the 18 cases) by a factor of about two when compared to the single most expensive component of a given multilevel calculation, and in all 18 cases the accuracy of the atomization energy for the three test molecules improves; with an average improvement of 16.7 kcal/mol.

Multilevel ensemble Kalman filtering

KAUST Repository

Hoel, Hakon

2016-06-14

This work embeds a multilevel Monte Carlo sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF) in the setting of finite dimensional signal evolution and noisy discrete-time observations. The signal dynamics is assumed to be governed by a stochastic differential equation (SDE), and a hierarchy of time grids is introduced for multilevel numerical integration of that SDE. The resulting multilevel EnKF is proved to asymptotically outperform EnKF in terms of computational cost versus approximation accuracy. The theoretical results are illustrated numerically.

Multilevel ensemble Kalman filtering

KAUST Repository

Hoel, Hakon; Law, Kody J. H.; Tempone, Raul

2016-01-01

This work embeds a multilevel Monte Carlo sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF) in the setting of finite dimensional signal evolution and noisy discrete-time observations. The signal dynamics is assumed to be governed by a stochastic differential equation (SDE), and a hierarchy of time grids is introduced for multilevel numerical integration of that SDE. The resulting multilevel EnKF is proved to asymptotically outperform EnKF in terms of computational cost versus approximation accuracy. The theoretical results are illustrated numerically.

Social Capital and Health: A Review of Prospective Multilevel Studies

Science.gov (United States)

Murayama, Hiroshi; Fujiwara, Yoshinori; Kawachi, Ichiro

2012-01-01

Background This article presents an overview of the concept of social capital, reviews prospective multilevel analytic studies of the association between social capital and health, and discusses intervention strategies that enhance social capital. Methods We conducted a systematic search of published peer-reviewed literature on the PubMed database and categorized studies according to health outcome. Results We identified 13 articles that satisfied the inclusion criteria for the review. In general, both individual social capital and area/workplace social capital had positive effects on health outcomes, regardless of study design, setting, follow-up period, or type of health outcome. Prospective studies that used a multilevel approach were mainly conducted in Western countries. Although we identified some cross-sectional multilevel studies that were conducted in Asian countries, including Japan, no prospective studies have been conducted in Asia. Conclusions Prospective evidence from multilevel analytic studies of the effect of social capital on health is very limited at present. If epidemiologic findings on the association between social capital and health are to be put to practical use, we must gather additional evidence and explore the feasibility of interventions that build social capital as a means of promoting health. PMID:22447212

Group Representations and Intergroup Bias: Positive Affect, Similarity, and Group Size.

Science.gov (United States)

Dovidio, John F.; And Others

1995-01-01

Examined how social appearance and affective factors can influence social categorization and intergroup bias. Positive affect increased the extent to which subjects formed inclusive group representations, anticipating that the members of two groups would feel like one. Subjects in dissimilarly dressed groups expected the members to feel less like…

Multilevel geometry optimization

Energy Technology Data Exchange (ETDEWEB)

Rodgers, Jocelyn M. [Department of Chemistry and Supercomputer Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431 (United States); Fast, Patton L. [Department of Chemistry and Supercomputer Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431 (United States); Truhlar, Donald G. [Department of Chemistry and Supercomputer Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431 (United States)

2000-02-15

Geometry optimization has been carried out for three test molecules using six multilevel electronic structure methods, in particular Gaussian-2, Gaussian-3, multicoefficient G2, multicoefficient G3, and two multicoefficient correlation methods based on correlation-consistent basis sets. In the Gaussian-2 and Gaussian-3 methods, various levels are added and subtracted with unit coefficients, whereas the multicoefficient Gaussian-x methods involve noninteger parameters as coefficients. The multilevel optimizations drop the average error in the geometry (averaged over the 18 cases) by a factor of about two when compared to the single most expensive component of a given multilevel calculation, and in all 18 cases the accuracy of the atomization energy for the three test molecules improves; with an average improvement of 16.7 kcal/mol. (c) 2000 American Institute of Physics.

Multilevel models applications using SAS

CERN Document Server

Wang, Jichuan; Fisher, James F

2011-01-01

This book covers a broad range of topics about multilevel modeling. The goal is to help readers to understand the basic concepts, theoretical frameworks, and application methods of multilevel modeling. It is at a level also accessible to non-mathematicians, focusing on the methods and applications of various multilevel models and using the widely used statistical software SAS®. Examples are drawn from analysis of real-world research data.

Co-occurrences Between Adolescent Substance Use and Academic Performance: School Context Inuences a Multilevel-Longitudinal Perspective

Science.gov (United States)

Andrade, Fernando H.

2014-01-01

A growing body of literature has linked substance use and academic performance exploring substance use as a predictor of academic performance or vice versa. This study uses a different approach conceptualizing substance use and academic performance as parallel outcomes and exploring two topics: its multilevel-longitudinal association and school contextual effects on both outcomes. Using multilevel Confirmatory Factor Analysis and multilevel-longitudinal analyses, the empirical estimates relied on 7843 students nested in 114 schools (Add Health study). The main finding suggests that the correlation between substance use and academic performance was positive at the school level in contraposition to the negative relationship at the individual level. Additional findings suggest a positive effect of a school risk factor on substance use and a positive effect of academic pressure on academic performance. These findings represent a contribution to our understanding of how schools could affect the relationship between academic performance and substance use. PMID:25057764

Multilevel models for longitudinal data

OpenAIRE

Fiona Steele

2008-01-01

Repeated measures and repeated events data have a hierarchical structure which can be analysed by using multilevel models. A growth curve model is an example of a multilevel random-coefficients model, whereas a discrete time event history model for recurrent events can be fitted as a multilevel logistic regression model. The paper describes extensions to the basic growth curve model to handle auto-correlated residuals, multiple-indicator latent variables and correlated growth processes, and e...

Multilevel ensemble Kalman filter

KAUST Repository

Chernov, Alexey; Hoel, Haakon; Law, Kody; Nobile, Fabio; Tempone, Raul

2016-01-01

This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

Multilevel ensemble Kalman filter

KAUST Repository

Chernov, Alexey

2016-01-06

This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

Governance and the Commons in a Multi-Level World

Directory of Open Access Journals (Sweden)

Derek Armitage

2007-11-01

Full Text Available Multi-level governance may facilitate learning and adaptation in complex social-ecological circumstances. Such arrangements should connect community-based management with regional/national government-level management, link scientific management and traditional management systems, encourage the sharing of knowledge and information, and promote collaboration and dialogue around goals and outcomes. Governance innovations of this type can thus build capacity to adapt to change and manage for resilience. However, critical reflection on the emergence of adaptive, multi-level governance for the commons is warranted. Drawing on examples from the North and South, the purpose of this review is to connect three complementary bodies of scholarship with insights for commons governance in a multi-level world: common property theory, resilience thinking and political ecology. From the commons and resilience literature, normative principles of adaptive, multi-level governance are synthesized (e.g., participation, accountability, leadership, knowledge pluralism, learning and trust. Political ecological interpretations, however, help to reveal the challenge of actualizing these principles and the contextual forces that make entrenched, top-down management systems resilient to change. These forces include the role of power, scale and levels of organization, knowledge valuation, the positioning of social actors and social constructions of nature. Also addressed are the policy narratives that shape governance, and the dialectic relationship among ecological systems and social change. tekst

[How to fit and interpret multilevel models using SPSS].

Science.gov (United States)

Pardo, Antonio; Ruiz, Miguel A; San Martín, Rafael

2007-05-01

Hierarchic or multilevel models are used to analyse data when cases belong to known groups and sample units are selected both from the individual level and from the group level. In this work, the multilevel models most commonly discussed in the statistic literature are described, explaining how to fit these models using the SPSS program (any version as of the 11 th ) and how to interpret the outcomes of the analysis. Five particular models are described, fitted, and interpreted: (1) one-way analysis of variance with random effects, (2) regression analysis with means-as-outcomes, (3) one-way analysis of covariance with random effects, (4) regression analysis with random coefficients, and (5) regression analysis with means- and slopes-as-outcomes. All models are explained, trying to make them understandable to researchers in health and behaviour sciences.

Psychological and Social Work Factors as Predictors of Mental Distress and Positive Affect: A Prospective, Multilevel Study.

Directory of Open Access Journals (Sweden)

Live Bakke Finne

Full Text Available Occupational health research has mainly addressed determinants of negative health effects, typically employing individual-level self-report data. The present study investigated individual- and department-level (means of each work unit effects of psychological/social work factors on mental distress and positive affect. Employees were recruited from 63 Norwegian organizations, representing a wide variety of job types. A total of 4158 employees, in 918 departments, responded at baseline and at follow-up two years later. Multilevel linear regressions estimated individual- and department-level effects simultaneously, and accounted for clustering of data. Baseline exposures and average exposures over time ([T1+T2]/2 were tested. All work factors; decision control, role conflict, positive challenge, support from immediate superior, fair leadership, predictability during the next month, commitment to organization, rumors of change, human resource primacy, and social climate, were related to mental distress and positive affect at the individual and department level. However, analyses of baseline exposures adjusted for baseline outcome, demonstrated significant associations at the individual level only. Baseline "rumors of change" was related to mental distress only and baseline "predictability during the next month" was not a statistical significant predictor of either outcome when adjusted for outcome at baseline. Psychological and social work factors were generally related to mental distress and positive affect in a mirrored way. Impact of exposures seemed most pervasive at the individual level. However, department-level relations were also discovered. Supplementing individual-level measures with aggregated measures may increase understanding of working conditions influence on employees`health and well-being. Organizational improvements focusing on the work factors in the current study should be able to reduce distress and enhance positive affect

Psychological and Social Work Factors as Predictors of Mental Distress and Positive Affect: A Prospective, Multilevel Study.

Science.gov (United States)

Finne, Live Bakke; Christensen, Jan Olav; Knardahl, Stein

2016-01-01

Occupational health research has mainly addressed determinants of negative health effects, typically employing individual-level self-report data. The present study investigated individual- and department-level (means of each work unit) effects of psychological/social work factors on mental distress and positive affect. Employees were recruited from 63 Norwegian organizations, representing a wide variety of job types. A total of 4158 employees, in 918 departments, responded at baseline and at follow-up two years later. Multilevel linear regressions estimated individual- and department-level effects simultaneously, and accounted for clustering of data. Baseline exposures and average exposures over time ([T1+T2]/2) were tested. All work factors; decision control, role conflict, positive challenge, support from immediate superior, fair leadership, predictability during the next month, commitment to organization, rumors of change, human resource primacy, and social climate, were related to mental distress and positive affect at the individual and department level. However, analyses of baseline exposures adjusted for baseline outcome, demonstrated significant associations at the individual level only. Baseline "rumors of change" was related to mental distress only and baseline "predictability during the next month" was not a statistical significant predictor of either outcome when adjusted for outcome at baseline. Psychological and social work factors were generally related to mental distress and positive affect in a mirrored way. Impact of exposures seemed most pervasive at the individual level. However, department-level relations were also discovered. Supplementing individual-level measures with aggregated measures may increase understanding of working conditions influence on employees`health and well-being. Organizational improvements focusing on the work factors in the current study should be able to reduce distress and enhance positive affect. Furthermore, both

The Educational Gradient in Intermarriage: A Comparative Analysis of Immigrant Groups in the United States

Science.gov (United States)

Kalmijn, Matthijs

2012-01-01

A common claim in the literature is that higher-educated persons are more likely to marry outside their ethnic/racial group than lower-educated persons. We re-examine this "educational gradient" with a multilevel analysis of 46 immigrant groups in the Current Population Survey. We find that there are positive effects not only of individual…

Advancing multilevel thinking and methods in HRM research

NARCIS (Netherlands)

Renkema, Maarten; Meijerink, Jeroen Gerard; Bondarouk, Tatiana

2016-01-01

Purpose Despite the growing belief that multilevel research is necessary to advance HRM understanding, there remains a lack of multilevel thinking – the application of principles for multilevel theory building. The purpose of this paper is to propose a systematic approach for multilevel HRM

Surgical management of contiguous multilevel thoracolumbar tuberculous spondylitis.

Science.gov (United States)

Qureshi, Muhammad Asad; Khalique, Ahmed Bilal; Afzal, Waseem; Pasha, Ibrahim Farooq; Aebi, Max

2013-06-01

Tuberculous spondylitis (TBS) is the most common form of extra-pulmonary tuberculosis. The mainstay of TBS management is anti-tuberculous chemotherapy. Most of the patients with TBS are treated conservatively; however in some patients surgery is indicated. Most common indications for surgery include neurological deficit, deformity, instability, large abscesses and necrotic tissue mass or inadequate response to anti-tuberculous chemotherapy. The most common form of TBS involves a single motion segment of spine (two adjoining vertebrae and their intervening disc). Sometimes TBS involves more than two adjoining vertebrae, when it is called multilevel TBS. Indications for correct surgical management of multilevel TBS is not clear from literature. We have retrospectively reviewed 87 patients operated in 10 years for multilevel TBS involving the thoracolumbar spine at our spine unit. Two types of surgeries were performed on these patients. In 57 patients, modified Hong Kong operation was performed with radical debridement, strut grafting and anterior instrumentation. In 30 patients this operation was combined with pedicle screw fixation with or without correction of kyphosis by osteotomy. Patients were followed up for correction of kyphosis, improvement in neurological deficit, pain and function. Complications were noted. On long-term follow-up (average 64 months), there was 9.34 % improvement in kyphosis angle in the modified Hong Kong group and 47.58 % improvement in the group with pedicle screw fixation and osteotomy in addition to anterior surgery (p debridement and anterior column reconstruction.

Co-occurrences between adolescent substance use and academic performance: school context influences a multilevel-longitudinal perspective.

Science.gov (United States)

Andrade, Fernando H

2014-08-01

A growing body of literature has linked substance use and academic performance exploring substance use as a predictor of academic performance or vice versa. This study uses a different approach conceptualizing substance use and academic performance as parallel outcomes and exploring two topics: its multilevel-longitudinal association and school contextual effects on both outcomes. Using multilevel Confirmatory Factor Analysis and multilevel-longitudinal analyses, the empirical estimates relied on 7843 students nested in 114 schools (Add Health study). The main finding suggests that the correlation between substance use and academic performance was positive at the school level in contraposition to the negative relationship at the individual level. Additional findings suggest a positive effect of a school risk factor on substance use and a positive effect of academic pressure on academic performance. These findings represent a contribution to our understanding of how schools could affect the relationship between academic performance and substance use. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Cognitive synergy in groups and group-to-individual transfer of decision-making competencies

Science.gov (United States)

Curşeu, Petru L.; Meslec, Nicoleta; Pluut, Helen; Lucas, Gerardus J. M.

2015-01-01

In a field study (148 participants organized in 38 groups) we tested the effect of group synergy and one's position in relation to the collaborative zone of proximal development (CZPD) on the change of individual decision-making competencies. We used two parallel sets of decision tasks reported in previous research to test rationality and we evaluated individual decision-making competencies in the pre-group and post-group conditions as well as group rationality (as an emergent group level phenomenon). We used multilevel modeling to analyze the data and the results showed that members of synergetic groups had a higher cognitive gain as compared to members of non-synergetic groups, while highly rational members (members above the CZPD) had lower cognitive gains compared to less rational group members (members situated below the CZPD). These insights extend the literature on group-to-individual transfer of learning and have important practical implications as they show that group dynamics influence the development of individual decision-making competencies. PMID:26441750

Cognitive synergy in groups and group-to-individual transfer of decision-making competencies.

Science.gov (United States)

Curşeu, Petru L; Meslec, Nicoleta; Pluut, Helen; Lucas, Gerardus J M

2015-01-01

In a field study (148 participants organized in 38 groups) we tested the effect of group synergy and one's position in relation to the collaborative zone of proximal development (CZPD) on the change of individual decision-making competencies. We used two parallel sets of decision tasks reported in previous research to test rationality and we evaluated individual decision-making competencies in the pre-group and post-group conditions as well as group rationality (as an emergent group level phenomenon). We used multilevel modeling to analyze the data and the results showed that members of synergetic groups had a higher cognitive gain as compared to members of non-synergetic groups, while highly rational members (members above the CZPD) had lower cognitive gains compared to less rational group members (members situated below the CZPD). These insights extend the literature on group-to-individual transfer of learning and have important practical implications as they show that group dynamics influence the development of individual decision-making competencies.

Predicting multi-level drug response with gene expression profile in multiple myeloma using hierarchical ordinal regression.

Science.gov (United States)

Zhang, Xinyan; Li, Bingzong; Han, Huiying; Song, Sha; Xu, Hongxia; Hong, Yating; Yi, Nengjun; Zhuang, Wenzhuo

2018-05-10

Multiple myeloma (MM), like other cancers, is caused by the accumulation of genetic abnormalities. Heterogeneity exists in the patients' response to treatments, for example, bortezomib. This urges efforts to identify biomarkers from numerous molecular features and build predictive models for identifying patients that can benefit from a certain treatment scheme. However, previous studies treated the multi-level ordinal drug response as a binary response where only responsive and non-responsive groups are considered. It is desirable to directly analyze the multi-level drug response, rather than combining the response to two groups. In this study, we present a novel method to identify significantly associated biomarkers and then develop ordinal genomic classifier using the hierarchical ordinal logistic model. The proposed hierarchical ordinal logistic model employs the heavy-tailed Cauchy prior on the coefficients and is fitted by an efficient quasi-Newton algorithm. We apply our hierarchical ordinal regression approach to analyze two publicly available datasets for MM with five-level drug response and numerous gene expression measures. Our results show that our method is able to identify genes associated with the multi-level drug response and to generate powerful predictive models for predicting the multi-level response. The proposed method allows us to jointly fit numerous correlated predictors and thus build efficient models for predicting the multi-level drug response. The predictive model for the multi-level drug response can be more informative than the previous approaches. Thus, the proposed approach provides a powerful tool for predicting multi-level drug response and has important impact on cancer studies.

Multilevel marketing společnosti Amway

OpenAIRE

Drozdková, Markéta

2010-01-01

This thesis analyses effectiveness and principles of multilevel marketing as a possible way of selling products and services. Theoretical part describes basis of marketing and direct selling, which is the basis of multilevel marketing. The thesis also states illegal forms of selling that misuse the advantages of multilevel marketing. Pracical part applies gained knowledge on Amway corporation and it atteds to operation of the company, which is evaluated by SWOT analysis.

Comparison of Functional and Radiological Outcomes Between Two Posterior Approaches in the Treatment of Multilevel Cervical Spondylotic Myelopathy.

Science.gov (United States)

Ren, Da-Jiang; Li, Fang; Zhang, Zhi-Cheng; Kai, Guan; Shan, Jian-Lin; Zhao, Guang-Min; Sun, Tian-Sheng

2015-08-05

Posterior cervical decompression is an accepted treatment for multilevel cervical spondylotic myelopathy (CSM). Each posterior technique has its own advantages and disadvantages. In the present study, we compared the functional and radiological outcomes of expansive hemilaminectomy and laminoplasty with mini titanium plate in the treatment of multilevel CSM. Forty-four patients with multilevel CSM treated with posterior cervical surgery in Department of Orthopedic Surgery, Beijing Army General Hospital from March 2011 to June 2012 were enrolled in this retrospective study. Patients were divided into two groups by surgical procedure: Laminoplasty (Group L) and hemilaminectomy (Group H). Perioperative parameters including age, sex, duration of symptoms, operative duration, and intraoperative blood loss were recorded and compared. Spinal canal area, calculated using AutoCAD ® software(Autodesk Inc., San Rafael, CA, USA), and neurological improvement, evaluated with Japanese Orthopedic Association score, were also compared. Neurological improvement did not differ significantly between groups. Group H had a significantly shorter operative duration and significantly less blood loss. Mean expansion ratio was significantly greater in Group L (77.83 ± 6.41%) than in Group H (62.72 ± 3.86%) (P < 0.01). Both surgical approaches are safe and effective in treating multilevel CSM. Laminoplasty provides a greater degree of enlargement of the spinal canal, whereas expansive hemilaminectomy has the advantages of shorter operative duration and less intraoperative blood loss.

A Container-based Trusted Multi-level Security Mechanism

Directory of Open Access Journals (Sweden)

Li Xiao-Yong

2017-01-01

Full Text Available Multi-level security mechanism has been widely applied in the military, government, defense and other domains in which information is required to be divided by security-level. Through this type of security mechanism, users at different security levels are provided with information at corresponding security levels. Traditional multi-level security mechanism which depends on the safety of operating system finally proved to be not practical. We propose a container-based trusted multi-level security mechanism in this paper to improve the applicability of the multi-level mechanism. It guarantees multi-level security of the system through a set of multi-level security policy rules and trusted techniques. The technical feasibility and application scenarios are also discussed. The ease of realization, strong practical significance and low cost of our method will largely expand the application of multi-level security mechanism in real life.

What Makes a Difference for Disadvantaged Girls? Investigating the Interplay between Group Composition and Positive Youth Development in Sport

Directory of Open Access Journals (Sweden)

Hebe Schaillée

2015-06-01

Full Text Available It has been suggested that group composition can influence the experiences of individual group members in social programmes (Weiss, 1998. The purpose of the present study was to examine the relationship between peer group composition in sports programmes and positive youth development (PYD in disadvantaged girls, as well as to determine whether it was moderated by personal characteristics. Two hundred young women aged between 10 and 24 completed a questionnaire including, among others, the “Youth Experience Survey for Sport” (YES-S (MacDonald, Côté, Eys, & Deakin, 2012 and questions regarding participants’ socio-economic characteristics (i.e., nationality, education, family situation. Multilevel regression analyses were performed to take into account the hierarchical data structure. At the group level, a higher percentage of girls from a low educational track and with a migration background predicted greater PYD, as indicated by higher levels of personal and social skills, cognitive skills and goal setting. Results showed interaction effects between the respondents’ family structures on the participant and team levels. The overall statistical models for the different developmental domains accounted for variance ranging from 14.7% (personal and social skills to 30.3% (cognitive skills. Results indicated that the extent to which disadvantaged girls derive benefits from their participation in sport also depends on the group composition. The interaction effects between the group composition and individual characteristics suggest that when girls participate in a group of similar peers, those from non-intact families will derive more benefits than their counterparts from intact families.

Multi-Level Secure Local Area Network

OpenAIRE

Naval Postgraduate School (U.S.); Center for Information Systems Studies Security and Research (CISR)

2011-01-01

Multi-Level Secure Local Area Network is a cost effective, multi-level, easy to use office environment leveraging existing high assurance technology. The Department of Defense and U.S. Government have an identified need to securely share information classified at differing security levels. Because there exist no commercial solutions to this problem, NPS is developing a MLS LAN. The MLS LAN extends high assurance capabilities of an evaluated multi-level secure system to commercial personal com...

Modeling Multi-Level Systems

CERN Document Server

Iordache, Octavian

2011-01-01

This book is devoted to modeling of multi-level complex systems, a challenging domain for engineers, researchers and entrepreneurs, confronted with the transition from learning and adaptability to evolvability and autonomy for technologies, devices and problem solving methods. Chapter 1 introduces the multi-scale and multi-level systems and highlights their presence in different domains of science and technology. Methodologies as, random systems, non-Archimedean analysis, category theory and specific techniques as model categorification and integrative closure, are presented in chapter 2. Chapters 3 and 4 describe polystochastic models, PSM, and their developments. Categorical formulation of integrative closure offers the general PSM framework which serves as a flexible guideline for a large variety of multi-level modeling problems. Focusing on chemical engineering, pharmaceutical and environmental case studies, the chapters 5 to 8 analyze mixing, turbulent dispersion and entropy production for multi-scale sy...

Comparison of Functional and Radiological Outcomes Between Two Posterior Approaches in the Treatment of Multilevel Cervical Spondylotic Myelopathy

Directory of Open Access Journals (Sweden)

Da-Jiang Ren

2015-01-01

Full Text Available Background: Posterior cervical decompression is an accepted treatment for multilevel cervical spondylotic myelopathy (CSM. Each posterior technique has its own advantages and disadvantages. In the present study, we compared the functional and radiological outcomes of expansive hemilaminectomy and laminoplasty with mini titanium plate in the treatment of multilevel CSM. Methods: Forty-four patients with multilevel CSM treated with posterior cervical surgery in Department of Orthopedic Surgery, Beijing Army General Hospital from March 2011 to June 2012 were enrolled in this retrospective study. Patients were divided into two groups by surgical procedure: Laminoplasty (Group L and hemilaminectomy (Group H. Perioperative parameters including age, sex, duration of symptoms, operative duration, and intraoperative blood loss were recorded and compared. Spinal canal area, calculated using AutoCAD ® software(Autodesk Inc., San Rafael, CA, USA, and neurological improvement, evaluated with Japanese Orthopedic Association score, were also compared. Results: Neurological improvement did not differ significantly between groups. Group H had a significantly shorter operative duration and significantly less blood loss. Mean expansion ratio was significantly greater in Group L (77.83 ± 6.41% than in Group H (62.72 ± 3.86% (P < 0.01. Conclusions: Both surgical approaches are safe and effective in treating multilevel CSM. Laminoplasty provides a greater degree of enlargement of the spinal canal, whereas expansive hemilaminectomy has the advantages of shorter operative duration and less intraoperative blood loss.

Multilevel classification of security concerns in cloud computing

Directory of Open Access Journals (Sweden)

Syed Asad Hussain

2017-01-01

Full Text Available Threats jeopardize some basic security requirements in a cloud. These threats generally constitute privacy breach, data leakage and unauthorized data access at different cloud layers. This paper presents a novel multilevel classification model of different security attacks across different cloud services at each layer. It also identifies attack types and risk levels associated with different cloud services at these layers. The risks are ranked as low, medium and high. The intensity of these risk levels depends upon the position of cloud layers. The attacks get more severe for lower layers where infrastructure and platform are involved. The intensity of these risk levels is also associated with security requirements of data encryption, multi-tenancy, data privacy, authentication and authorization for different cloud services. The multilevel classification model leads to the provision of dynamic security contract for each cloud layer that dynamically decides about security requirements for cloud consumer and provider.

Multilevel Modulation formats for Optical Communication

DEFF Research Database (Denmark)

Jensen, Jesper Bevensee

2008-01-01

This thesis studies the use of multilevel modulation formats for optical communication systems. Multilevel modulation is an attractive method of increasing the spectral efficiency of optical communication systems. Various modulation formats employing phase modulation, amplitude modulation...... or a combination of the two have been studied. The use of polarization multiplexing (PolMux) to double the bit rate has also been investigated. The impact of transmission impairments such as chromatic dispersion, self phase modulation and cross phase modulation has been investigated. The feasibility of multilevel...... modulation for network oriented scenarios has been demonstrated....

Multilevel index decomposition analysis: Approaches and application

International Nuclear Information System (INIS)

Xu, X.Y.; Ang, B.W.

2014-01-01

With the growing interest in using the technique of index decomposition analysis (IDA) in energy and energy-related emission studies, such as to analyze the impacts of activity structure change or to track economy-wide energy efficiency trends, the conventional single-level IDA may not be able to meet certain needs in policy analysis. In this paper, some limitations of single-level IDA studies which can be addressed through applying multilevel decomposition analysis are discussed. We then introduce and compare two multilevel decomposition procedures, which are referred to as the multilevel-parallel (M-P) model and the multilevel-hierarchical (M-H) model. The former uses a similar decomposition procedure as in the single-level IDA, while the latter uses a stepwise decomposition procedure. Since the stepwise decomposition procedure is new in the IDA literature, the applicability of the popular IDA methods in the M-H model is discussed and cases where modifications are needed are explained. Numerical examples and application studies using the energy consumption data of the US and China are presented. - Highlights: • We discuss the limitations of single-level decomposition in IDA applied to energy study. • We introduce two multilevel decomposition models, study their features and discuss how they can address the limitations. • To extend from single-level to multilevel analysis, necessary modifications to some popular IDA methods are discussed. • We further discuss the practical significance of the multilevel models and present examples and cases to illustrate

Fault-Tolerant Control for a Flexible Group Battery Energy Storage System Based on Cascaded Multilevel Converters

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Junhong Song

2018-01-01

Full Text Available A flexible group battery energy storage system (FGBESS based on cascaded multilevel converters is attractive for renewable power generation applications because of its high modularity and high power quality. However, reliability is one of the most important issues and the system may suffer from great financial loss after fault occurs. In this paper, based on conventional fundamental phase shift compensation and third harmonic injection, a hybrid compensation fault-tolerant method is proposed to improve the post-fault performance in the FGBESS. By adjusting initial phase offset and amplitude of injected component, the optimal third harmonic injection is generated in an asymmetric system under each faulty operation. Meanwhile, the optimal redundancy solution under each fault condition is also elaborated comprehensively with a comparison of the presented three fault-tolerant strategies. This takes full advantage of battery utilization and minimizes the loss of energy capacity. Finally, the effectiveness and feasibility of the proposed methods are verified by results obtained from simulations and a 10 kW experimental platform.

Multilevel sequential Monte-Carlo samplers

KAUST Repository

Jasra, Ajay

2016-01-01

Multilevel Monte-Carlo methods provide a powerful computational technique for reducing the computational cost of estimating expectations for a given computational effort. They are particularly relevant for computational problems when approximate distributions are determined via a resolution parameter h, with h=0 giving the theoretical exact distribution (e.g. SDEs or inverse problems with PDEs). The method provides a benefit by coupling samples from successive resolutions, and estimating differences of successive expectations. We develop a methodology that brings Sequential Monte-Carlo (SMC) algorithms within the framework of the Multilevel idea, as SMC provides a natural set-up for coupling samples over different resolutions. We prove that the new algorithm indeed preserves the benefits of the multilevel principle, even if samples at all resolutions are now correlated.

Multilevel sequential Monte-Carlo samplers

KAUST Repository

Jasra, Ajay

2016-01-05

Multilevel Monte-Carlo methods provide a powerful computational technique for reducing the computational cost of estimating expectations for a given computational effort. They are particularly relevant for computational problems when approximate distributions are determined via a resolution parameter h, with h=0 giving the theoretical exact distribution (e.g. SDEs or inverse problems with PDEs). The method provides a benefit by coupling samples from successive resolutions, and estimating differences of successive expectations. We develop a methodology that brings Sequential Monte-Carlo (SMC) algorithms within the framework of the Multilevel idea, as SMC provides a natural set-up for coupling samples over different resolutions. We prove that the new algorithm indeed preserves the benefits of the multilevel principle, even if samples at all resolutions are now correlated.

Multilevel modelling: Beyond the basic applications.

Science.gov (United States)

Wright, Daniel B; London, Kamala

2009-05-01

Over the last 30 years statistical algorithms have been developed to analyse datasets that have a hierarchical/multilevel structure. Particularly within developmental and educational psychology these techniques have become common where the sample has an obvious hierarchical structure, like pupils nested within a classroom. We describe two areas beyond the basic applications of multilevel modelling that are important to psychology: modelling the covariance structure in longitudinal designs and using generalized linear multilevel modelling as an alternative to methods from signal detection theory (SDT). Detailed code for all analyses is described using packages for the freeware R.

Group-analytic epistemology and the articulation of group-treatment setting in a Department of Mental Health

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Nicoletta Della Torre

2014-09-01

Full Text Available This paper addresses the issue of multi-level projects of care to mental disorders patients in the context of the Mental Health Centre, proposing an epistemological point of view on groups inspired to the epistemology of complexity.Keywords: Multi-level projects of care; Mental Health Centre; Epistemology of Complexity

Acculturation, out-group positivity and eating disorders symptoms among Emirati women.

Science.gov (United States)

Thomas, Justin; O'Hara, Lily; Quadflieg, Susanne; Weissgerber, Sophia Christin

2018-04-01

Western acculturation has been implicated in the development of eating disorders among populations living outside Europe and North America. This study explored the relationship between Western acculturation, in-group/out-group evaluations and eating disorders symptoms among female citizens of the United Arab Emirates (UAE). Emirati college women (N = 209) completed an affective priming task, designed to implicitly assess in-group (Emirati) and out-group (American) evaluations. Participants also completed the Westernization Survey, a widely used self-report measure of acculturation, and the Eating Attitudes Test (EAT-26). Across the whole sample, out-group positivity was correlated with higher levels of eating disorder symptoms. Participants classified as at risk for eating disorders showed a clear out-group preference (out-group positivity greater than in-group positivity). Western acculturation was also positively correlated with eating disorder symptoms. Overall, these findings lend further support to the acculturation hypothesis of eating disorders in the context of Emirati college women.

Multilevel Modelling with Spatial Interaction Effects with Application to an Emerging Land Market in Beijing, China.

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Guanpeng Dong

Full Text Available This paper develops a methodology for extending multilevel modelling to incorporate spatial interaction effects. The motivation is that classic multilevel models are not specifically spatial. Lower level units may be nested into higher level ones based on a geographical hierarchy (or a membership structure--for example, census zones into regions but the actual locations of the units and the distances between them are not directly considered: what matters is the groupings but not how close together any two units are within those groupings. As a consequence, spatial interaction effects are neither modelled nor measured, confounding group effects (understood as some sort of contextual effect that acts 'top down' upon members of a group with proximity effects (some sort of joint dependency that emerges between neighbours. To deal with this, we incorporate spatial simultaneous autoregressive processes into both the outcome variable and the higher level residuals. To assess the performance of the proposed method and the classic multilevel model, a series of Monte Carlo simulations are conducted. The results show that the proposed method performs well in retrieving the true model parameters whereas the classic multilevel model provides biased and inefficient parameter estimation in the presence of spatial interactions. An important implication of the study is to be cautious of an apparent neighbourhood effect in terms of both its magnitude and statistical significance if spatial interaction effects at a lower level are suspected. Applying the new approach to a two-level land price data set for Beijing, China, we find significant spatial interactions at both the land parcel and district levels.

Graduate Attribute Attainment in a Multi-Level Undergraduate Geography Course

Science.gov (United States)

Mager, Sarah; Spronken-Smith, Rachel

2014-01-01

We investigated students' perceptions of graduate attributes in a multi-level (second and third year) geography course. A case study with mixed methodology was employed, with data collected through focus groups and a survey. We found that undergraduate geography students can identify the skills, knowledge and attributes that are developed through…

Social trust, interpersonal trust and self-rated health in China: a multi-level study.

Science.gov (United States)

Feng, Zhixin; Vlachantoni, Athina; Liu, Xiaoting; Jones, Kelvyn

2016-11-08

Trust is important for health at both the individual and societal level. Previous research using Western concepts of trust has shown that a high level of trust in society can positively affect individuals' health; however, it has been found that the concepts and culture of trust in China are different from those in Western countries and research on the relationship between trust and health in China is scarce. The analyses use data from the national scale China General Social Survey (CGSS) on adults aged above 18 in 2005 and 2010. Two concepts of trust ("out-group" and "in-group" trust) are used to examine the relationship between trust and self-rated health in China. Multilevel logistical models are applied, examining the trust at the individual and societal level on individuals' self-rated health. In terms of interpersonal trust, both "out-group" and "in-group" trust are positively associated with good health in 2005 and 2010. At the societal level, the relationships between the two concepts of trust and health are different. In 2005, higher "out-group" social trust (derived from trust in strangers) is positively associated with better health; however, higher "in-group" social trust (derived from trust in most people) is negatively associated with good health in 2010. The cross-level interactions show that lower educated individuals (no education or only primary level), rural residents and those on lower incomes are the most affected groups in societies with higher "out-group" social trust; whereas people with lower levels of educational attainment, a lower income, and those who think that most people can be trusted are the most affected groups in societies with higher "in-group" social trust. High levels of interpersonal trust are of benefit to health. Higher "out-group" social trust is positively associated with better health; while higher "in-group" social trust is negatively associated with good health. Individuals with different levels of educational

Antecedents of Organisational Creativity: A Multi-Level Approach

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Ritu Gupta

2016-06-01

Full Text Available The purpose of this literature review is to provide a better understanding of the antecedents of organisational creativity with a multi-level approach. Organisational creativity is a sum total of the creativity accounted for by the individual employees of the organisation, the cumulative creativity of a team or group and creativity arising out of different structural components of an organisation. Some of the antecedents identified from the literature include personality, intrinsic motivation, group cohesion, social inhibition, cognitive interference, leader member exchange, organisational culture and climate, amongst others at individual, group and organisational level. Based on the literature review, suggestions for future research and research propositions have been proposed.

Multilevel particle filter

KAUST Repository

Law, Kody

2016-01-06

This talk will pertain to the filtering of partially observed diffusions, with discrete-time observations. It is assumed that only biased approximations of the diffusion can be obtained, for choice of an accuracy parameter indexed by l. A multilevel estimator is proposed, consisting of a telescopic sum of increment estimators associated to the successive levels. The work associated to O( 2) mean-square error between the multilevel estimator and average with respect to the filtering distribution is shown to scale optimally, for example as O( 2) for optimal rates of convergence of the underlying diffusion approximation. The method is illustrated on some toy examples as well as estimation of interest rate based on real S&P 500 stock price data.

The Triple P-Positive Parenting Program: a systematic review and meta-analysis of a multi-level system of parenting support.

Science.gov (United States)

Sanders, Matthew R; Kirby, James N; Tellegen, Cassandra L; Day, Jamin J

2014-06-01

This systematic review and meta-analysis examined the effects of the multilevel Triple P-Positive Parenting Program system on a broad range of child, parent and family outcomes. Multiple search strategies identified 116 eligible studies conducted over a 33-year period, with 101 studies comprising 16,099 families analyzed quantitatively. Moderator analyses were conducted using structural equation modeling. Risk of bias within and across studies was assessed. Significant short-term effects were found for: children's social, emotional and behavioral outcomes (d=0.473); parenting practices (d=0.578); parenting satisfaction and efficacy (d=0.519); parental adjustment (d=0.340); parental relationship (d=0.225) and child observational data (d=0.501). Significant effects were found for all outcomes at long-term including parent observational data (d=0.249). Moderator analyses found that study approach, study power, Triple P level, and severity of initial child problems produced significant effects in multiple moderator models when controlling for other significant moderators. Several putative moderators did not have significant effects after controlling for other significant moderators. The positive results for each level of the Triple P system provide empirical support for a blending of universal and targeted parenting interventions to promote child, parent and family wellbeing. Copyright © 2014 Elsevier Ltd. All rights reserved.

Social participation and mortality: does social position in civic groups matter?

Directory of Open Access Journals (Sweden)

Yoshiki Ishikawa

2016-05-01

Full Text Available Abstract Background Social participation is known to predict longevity. However, little is known about the effect of social participation according to an individual’s position in civic groups. We evaluated the influence of social position on mortality, using data from a large cohort of Japanese older adults (the AGES cohort. Methods Of 14,804 individuals aged 65 years and older enrolled in the AGES, 14,286 individuals were followed up for approximately 5 years from 2003 to 2008. We performed inverse probability of treatment weighted (IPTW Cox proportional hazards regression with multiple imputation of missing values to compute hazard ratios (HR for all-cause mortality according to the individual’s position in the community organization(s to which they belonged. We examined participation in the following civic groups: neighborhood association/senior citizen club/fire-fighting team, religious group, political organization or group, industrial or trade association, volunteer group, citizen or consumer group, hobby group, and sports group or club. The values for IPTW were computed based on demographic variables, socioeconomic status, and self-reported medical condition. Results During 22,718 person-years of follow-up for regular members of community groups and 14,014 person-years of follow-up for participants in leadership positions, 479 deaths and 214 deaths were observed, respectively. Relative to regular members, crude HR for all-cause mortality for occupying leadership positions (e.g. president, manager, or having administrative roles was 0.72 (95 % CI:0.62–0.85. The IPTW-HR was 0.88 (95 % CI: 0.79–0.99 for participants occupying leadership positions. Conclusions Holding leadership positions in community organization(s may be more beneficial to health than being regular members.

Kin and multilevel selection in social evolution: a never-ending controversy? [version 1; referees: 4 approved

Directory of Open Access Journals (Sweden)

Jos Kramer

2016-04-01

Full Text Available Kin selection and multilevel selection are two major frameworks in evolutionary biology that aim at explaining the evolution of social behaviors. However, the relationship between these two theories has been plagued by controversy for almost half a century and debates about their relevance and usefulness in explaining social evolution seem to rekindle at regular intervals. Here, we first provide a concise introduction into the kin selection and multilevel selection theories and shed light onto the roots of the controversy surrounding them. We then review two major aspects of the current debate: the presumed formal equivalency of the two theories and the question whether group selection can lead to group adaptation. We conclude by arguing that the two theories can offer complementary approaches to the study of social evolution: kin selection approaches usually focus on the identification of optimal phenotypes and thus on the endresult of a selection process, whereas multilevel selection approaches focus on the ongoing selection process itself. The two theories thus provide different perspectives that might be fruitfully combined to promote our understanding of the evolution in group-structured populations.

The multilevel governance of migration and integration

NARCIS (Netherlands)

Scholten, P.; Penninx, R.; Garcés–Mascareñas, B.; Penninx, R.

2016-01-01

This chapter focuses on migration and integration as multilevel policy issues and explores the consequences in terms of multilevel governance. Immigration policymaking has been characterized by continued struggle between national governments and the EU about the amount of discretion states have in

Multilevel security for relational databases

CERN Document Server

Faragallah, Osama S; El-Samie, Fathi E Abd

2014-01-01

Concepts of Database Security Database Concepts Relational Database Security Concepts Access Control in Relational Databases      Discretionary Access Control      Mandatory Access Control      Role-Based Access Control Work Objectives Book Organization Basic Concept of Multilevel Database Security IntroductionMultilevel Database Relations Polyinstantiation      Invisible Polyinstantiation      Visible Polyinstantiation      Types of Polyinstantiation      Architectural Consideration

Group intervention: A way to improve working teams' positive psychological capital.

Science.gov (United States)

Harty, Bo; Gustafsson, John-Anders; Björkdahl, Ann; Möller, Anders

2015-01-01

Positive psychological capital is reported to have positive effects on people's well-being and attitudes to their working lives. The objective of this study was to investigate if it is possible to increase the level of positive psychological capital by two group intervention programs. The research design was a controlled study with 2 × 2 experimental groups and two control groups. Two of the experimental groups received intervention I (IG I), the other two experimental groups received intervention II (IG II). Assessments were made before and after the intervention programs, with a follow-up at six months post-intervention. Instruments measuring the fundamentals of psychological capital: self-efficacy, hope, optimism, as well as health and job satisfaction were used. The results show that it is possible to increase the level of positive emotions, self-efficacy and job satisfaction of members of a working team by using group intervention methods. The positive changes observed at the end of the program remained six months after the intervention, with the exception of job satisfaction in IG II. It seems that the intervention had a greater influence on those persons who at the start of the study reported a low level of self-enhancement. The results were more pronounced in intervention group I where reinforcement of the resources and positive aspects of the work place environment were provided. A 10-week group intervention program that focused on learned optimism proved to be successful in increasing levels of self-efficacy and job satisfaction. While improvement was maintained six months post-intervention the small sample size and the attrition rate are limitations. Results are promising and further research is warranted.

Competing Forces of Socioeconomic Development and Environmental Degradation on Health and Happiness for Different Income Groups in China.

Science.gov (United States)

Gu, Lijuan; Rosenberg, Mark W; Zeng, Juxin

2017-10-01

China's rapid socioeconomic growth in recent years and the simultaneous increase in many forms of pollution are generating contradictory pictures of residents' well-being. This paper applies multilevel analysis to the 2013 China General Social Survey data on social development and health to understand this twofold phenomenon. Multilevel models are developed to investigate the impact of socioeconomic development and environmental degradation on self-reported health (SRH) and self-reported happiness (SRHP), differentiating among lower, middle, and higher income groups. The results of the logit multilevel analysis demonstrate that income, jobs, and education increased the likelihood of rating SRH and SRHP positively for the lower and middle groups but had little or no effect on the higher income group. Having basic health insurance had an insignificant effect on health but increased the likelihood of happiness among the lower income group. Provincial-level pollutants were associated with a higher likelihood of good health for all income groups, and community-level industrial pollutants increased the likelihood of good health for the lower and middle income groups. Measures of community-level pollution were robust predictors of the likelihood of unhappiness among the lower and middle income groups. Environmental hazards had a mediating effect on the relationship between socioeconomic development and health, and socioeconomic development strengthened the association between environmental hazards and happiness. These outcomes indicate that the complex interconnections among socioeconomic development and environmental degradation have differential effects on well-being among different income groups in China.

Group Positive Psychotherapy and Depression of Females Affected by Multiple Sclerosis

Directory of Open Access Journals (Sweden)

Tayebeh Khayatan

2014-12-01

Full Text Available Objectives: Multiple Sclerosis is one of the most important and prevalent central nervous system diseases, causing disorders such as depression among affected patients. Positive psychotherapy is also a new approach that can be effective in reducing the depression of these people. This study aims to investigate the efficiency of group positive psychotherapy for decreasing the depression among females affected by Multiple Sclerosis. Methods: A samples of 30 females affected by Multiple Sclerosis with mild to moderate depression were participated, and were divided into two groups, intervention and control. Both groups completed Beck Depression Inventory II (BDI-II at the beginning, he intervention group received six sessions of positive psychotherapy. After the intervention both group completed the questionnaire again. Data was analyzed by descriptive and inferential statistical methods. Results: The result demonstrated that, the decline of depression was more in the intervention group than the control group. Moreover in the intervention group than control group, there was obtained significant reduction in both sub-scales of Beck Depression Inventory II. Discussion: Results of this study indicated that group positive psychotherapy is effective in reducing the depression of females affected by Multiple Sclerosis. This treatment can be widely used in the caring centers for treatment of people affected by Multiple Sclerosis and this can be justified because of its low cost and good efficiency.

Multilevel optimization algorithms and applications

CERN Document Server

Pardalos, Panos; Värbrand, Peter

1998-01-01

Researchers working with nonlinear programming often claim "the word is non­ linear" indicating that real applications require nonlinear modeling. The same is true for other areas such as multi-objective programming (there are always several goals in a real application), stochastic programming (all data is uncer­ tain and therefore stochastic models should be used), and so forth. In this spirit we claim: The word is multilevel. In many decision processes there is a hierarchy of decision makers, and decisions are made at different levels in this hierarchy. One way to handle such hierar­ chies is to focus on one level and include other levels' behaviors as assumptions. Multilevel programming is the research area that focuses on the whole hierar­ chy structure. In terms of modeling, the constraint domain associated with a multilevel programming problem is implicitly determined by a series of opti­ mization problems which must be solved in a predetermined sequence. If only two levels are considered, we have ...

The Readability of Malaysian English Children Books: A Multilevel Analysis

Directory of Open Access Journals (Sweden)

Adlina Ismail

2016-11-01

Full Text Available These days, there are more English books for children published by local publishers in Malaysia. It is a positive development because the books will be more accessible to the children. However, the books have never been studied and evaluated in depth yet. One important factor in assessing reading materials is readability. Readability determines whether a text is easy or difficult to understand and a balanced mix of both can promote learning and language development. Various researchers mentioned a multilevel framework of discourse that any language assessment on a text should take into account. The levels that were proposed were word, syntax, textbase, situation model and genre and rhetorical structures. Traditional readability measures such as Flesh Reading Ease Formula, Gunning Readability Index, Fog Count, and Fry Grade Level are not able to address the multilevel because they are based on shallow variables. In contrast, Coh-metrix TERA provided five indices that are correlated to grade level and aligned to the multilevel framework. This study analyzed ten Malaysian English chapter books for children using this Coh-metrix TERA. The result revealed that the Malaysian English children books were easy in shallow level but there was a possible difficulty in textbase and situation model level because of the lack of cohesion. In conclusion, more attention should be given on deeper level of text rather than just word and syntax level.

Micro-macro multilevel latent class models with multiple discrete individual-level variables

NARCIS (Netherlands)

Bennink, M.; Croon, M.A.; Kroon, B.; Vermunt, J.K.

2016-01-01

An existing micro-macro method for a single individual-level variable is extended to the multivariate situation by presenting two multilevel latent class models in which multiple discrete individual-level variables are used to explain a group-level outcome. As in the univariate case, the

Attitudes toward Immigration as a Sense of Group Position

DEFF Research Database (Denmark)

Farah, Abdulkadir Osman

2018-01-01

such as affirmative action and immigration, we examine the extent to which American attitudes toward immigration can be conceptualized from a Blumerian sense of group position without setting Allport’s contact theory as an alternative hypothesis. Our findings show cultural and ideological threat, and subjective...... economic threat as more important in informing attitudes toward immigration than objective economic conditions; and social and ethnic location threat. Our findings are consistent with and confirm Blumer’s argument that prejudice as a sense of group position is primarily derived from feelings, and are...

Positive and Negative Perfectionism in Migrainus Patients Compaired with Control Group

Directory of Open Access Journals (Sweden)

H Afshar

2008-01-01

Full Text Available ABSTRACT: Introduction & Objective: The positive and negative effects of perfectionism on human cognition, affection and behavior have been emphasized. Perfectionism has been conceptualized as a multidimensional construct, with both adaptive and maladaptive aspects, which is one of the common personality traits that cause lifelong stress in human and results in anxiety, depression and physical and mental distress.The aim of this study was to assess the positive and negative perfectionism in migrainus patients in comparison with control group. Materials & Methods: This is an analytical (Case-control study which was performed on 91 migraine patients and 88 healthy individuals. The pqtients and controls completed a standard 40 item questionnaire for perfectionism – PANPS (20 for positive and 20 for negative perfectionism . The patients in both groups were matched for gender and age. Mean of positive and negative perfectionism scores for two groups was statistically analysed using SPSS software. Results: Mean positive perfectionism score was 83.47±8.5 for migraine group and 65.47±7.54 for control group (p=0.0001. The difference between two groups was significant. Mean of negative perfectionism score was 74.12±10.6 for migraine group and 51.79±7.8 for control group(p=0.0001. Conclusion: The results show that migraine patients have higher mean of perfectionism scores than healthy individuals. Based on this study and other clinical experiences more attention to psychotherapy is necessary for better management of migraine and recognition of personality profile in migraine patient helps to reduce patient’s complaints.

Scalable Adaptive Multilevel Solvers for Multiphysics Problems

Energy Technology Data Exchange (ETDEWEB)

Xu, Jinchao [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mathematics

2014-11-26

In this project, we carried out many studies on adaptive and parallel multilevel methods for numerical modeling for various applications, including Magnetohydrodynamics (MHD) and complex fluids. We have made significant efforts and advances in adaptive multilevel methods of the multiphysics problems: multigrid methods, adaptive finite element methods, and applications.

Income inequality and mortality: a multilevel prospective study of 521 248 individuals in 50 US states.

Science.gov (United States)

Backlund, Eric; Rowe, Geoff; Lynch, John; Wolfson, Michael C; Kaplan, George A; Sorlie, Paul D

2007-06-01

Some of the most consistent evidence in favour of an association between income inequality and health has been among US states. However, in multilevel studies of mortality, only two out of five studies have reported a positive relationship with income inequality after adjustment for the compositional characteristics of the state's inhabitants. In this study, we attempt to clarify these mixed results by analysing the relationship within age-sex groups and by applying a previously unused analytical method to a database that contains more deaths than any multilevel study to date. The US National Longitudinal Mortality Study (NLMS) was used to model the relationship between income inequality in US states and mortality using both a novel and previously used methodologies that fall into the general framework of multilevel regression. We adjust age-sex specific models for nine socioeconomic and demographic variables at the individual level and percentage black and region at the state level. The preponderance of evidence from this study suggests that 1990 state-level income inequality is associated with a 40% differential in state level mortality rates (95% CI = 26-56%) for men 25-64 years and a 14% (95% CI = 3-27%) differential for women 25-64 years after adjustment for compositional factors. No such relationship was found for men or women over 65. The relationship between income inequality and mortality is only robust to adjustment for compositional factors in men and women under 65. This explains why income inequality is not a major driver of mortality trends in the United States because most deaths occur at ages 65 and over. This analysis does suggest, however, the certain causes of death that occur primarily in the population under 65 may be associated with income inequality. Comparison of analytical techniques also suggests coefficients for income inequality in previous multilevel mortality studies may be biased, but further research is needed to provide a definitive

Multilevel ensemble Kalman filtering

KAUST Repository

Hoel, Haakon

2016-01-08

The ensemble Kalman filter (EnKF) is a sequential filtering method that uses an ensemble of particle paths to estimate the means and covariances required by the Kalman filter by the use of sample moments, i.e., the Monte Carlo method. EnKF is often both robust and efficient, but its performance may suffer in settings where the computational cost of accurate simulations of particles is high. The multilevel Monte Carlo method (MLMC) is an extension of classical Monte Carlo methods which by sampling stochastic realizations on a hierarchy of resolutions may reduce the computational cost of moment approximations by orders of magnitude. In this work we have combined the ideas of MLMC and EnKF to construct the multilevel ensemble Kalman filter (MLEnKF) for the setting of finite dimensional state and observation spaces. The main ideas of this method is to compute particle paths on a hierarchy of resolutions and to apply multilevel estimators on the ensemble hierarchy of particles to compute Kalman filter means and covariances. Theoretical results and a numerical study of the performance gains of MLEnKF over EnKF will be presented. Some ideas on the extension of MLEnKF to settings with infinite dimensional state spaces will also be presented.

Multilevel ensemble Kalman filtering

KAUST Repository

Hoel, Haakon; Chernov, Alexey; Law, Kody; Nobile, Fabio; Tempone, Raul

2016-01-01

The ensemble Kalman filter (EnKF) is a sequential filtering method that uses an ensemble of particle paths to estimate the means and covariances required by the Kalman filter by the use of sample moments, i.e., the Monte Carlo method. EnKF is often both robust and efficient, but its performance may suffer in settings where the computational cost of accurate simulations of particles is high. The multilevel Monte Carlo method (MLMC) is an extension of classical Monte Carlo methods which by sampling stochastic realizations on a hierarchy of resolutions may reduce the computational cost of moment approximations by orders of magnitude. In this work we have combined the ideas of MLMC and EnKF to construct the multilevel ensemble Kalman filter (MLEnKF) for the setting of finite dimensional state and observation spaces. The main ideas of this method is to compute particle paths on a hierarchy of resolutions and to apply multilevel estimators on the ensemble hierarchy of particles to compute Kalman filter means and covariances. Theoretical results and a numerical study of the performance gains of MLEnKF over EnKF will be presented. Some ideas on the extension of MLEnKF to settings with infinite dimensional state spaces will also be presented.

Multilevel Higher-Order Item Response Theory Models

Science.gov (United States)

Huang, Hung-Yu; Wang, Wen-Chung

2014-01-01

In the social sciences, latent traits often have a hierarchical structure, and data can be sampled from multiple levels. Both hierarchical latent traits and multilevel data can occur simultaneously. In this study, we developed a general class of item response theory models to accommodate both hierarchical latent traits and multilevel data. The…

The role of supervisor emotional support on individual job satisfaction: A multilevel analysis.

Science.gov (United States)

Pohl, Sabine; Galletta, Maura

2017-02-01

Supervisor emotional support is a strong determinant of job satisfaction. There is no study examining the effect of supervisor emotional support at the group level on job satisfaction. Multilevel statistical techniques can help disentangle the effects of subjective assessments from those of group factors. The study's aim was to examine the moderating role of supervisor emotional support (group-level variable) on the relationship between work engagement and job satisfaction (individual-level variables). A cross-sectional study was performed in 39units from three Belgian hospitals. A total of 323 nurses completed a self-reported questionnaire. We carried out a multilevel analysis by using Hierarchical Linear Modeling. The results showed that the cross-level interaction was significant. Hence, at individual-level, the nurses with high levels of work engagement showed high levels of job satisfaction and this relationship was stronger when supervisor emotional support at group-level was high. Contextual differences among groups had an impact on the form of the work engagement-job satisfaction relationship. This relationship between work engagement and job satisfaction is an individual and group level phenomenon. Ways to enhance emotional supervisor support include training supervisors in providing support and enhancing communication between nurses and supervisors. Copyright © 2016 Elsevier Inc. All rights reserved.

The Psychosocial Work Environment, Employee Mental Health and Organizational Interventions: Improving Research and Practice by Taking a Multilevel Approach.

Science.gov (United States)

Martin, Angela; Karanika-Murray, Maria; Biron, Caroline; Sanderson, Kristy

2016-08-01

Although there have been several calls for incorporating multiple levels of analysis in employee health and well-being research, studies examining the interplay between individual, workgroup, organizational and broader societal factors in relation to employee mental health outcomes remain an exception rather than the norm. At the same time, organizational intervention research and practice also tends to be limited by a single-level focus, omitting potentially important influences at multiple levels of analysis. The aims of this conceptual paper are to help progress our understanding of work-related determinants of employee mental health by the following: (1) providing a rationale for routine multilevel assessment of the psychosocial work environment; (2) discussing how a multilevel perspective can improve related organizational interventions; and (3) highlighting key theoretical and methodological considerations relevant to these aims. We present five recommendations for future research, relating to using appropriate multilevel research designs, justifying group-level constructs, developing group-level measures, expanding investigations to the organizational level and developing multilevel approaches to intervention design, implementation and evaluation. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

The Emergence of Individual and Collective Leadership in Task Groups

DEFF Research Database (Denmark)

Paunova, Minna

2015-01-01

leader emergence in task groups as influenced by individual traits, states, and behaviors. However, current approaches to leadership in groups rely on functional achievement explanations of how collective leadership emerges, influenced by positive states and behaviors. Attention to ascription......This review synthesizes conceptual and empirical research on the emergence of individual and collective leadership in task groups, and proposes avenues for leadership research. To advance multilevel study of leadership emergence, including emergence of distributed and shared leadership, the paper...... reviews research on individual leader emergence, structured around two identified theoretical mechanisms—one of leadership achievement (i.e., based on functional behaviors) and another of leadership ascription (i.e., based on nominal characteristics). These approaches compete to elucidate individual...

Promotion of cooperation by selective group extinction

Science.gov (United States)

Böttcher, Marvin A.; Nagler, Jan

2016-06-01

Multilevel selection is an important organizing principle that crucially underlies evolutionary processes from the emergence of cells to eusociality and the economics of nations. Previous studies on multilevel selection assumed that the effective higher-level selection emerges from lower-level reproduction. This leads to selection among groups, although only individuals reproduce. We introduce selective group extinction, where groups die with a probability inversely proportional to their group fitness. When accounting for this the critical benefit-to-cost ratio is substantially lowered. Because in game theory and evolutionary dynamics the degree of cooperation crucially depends on this ratio above which cooperation emerges, previous studies may have substantially underestimated the establishment and maintenance of cooperation.

Bridging the gap between biologic, individual, and macroenvironmental factors in cancer: a multilevel approach.

Science.gov (United States)

Lynch, Shannon M; Rebbeck, Timothy R

2013-04-01

To address the complex nature of cancer occurrence and outcomes, approaches have been developed to simultaneously assess the role of two or more etiologic agents within hierarchical levels including the: (i) macroenvironment level (e.g., health care policy, neighborhood, or family structure); (ii) individual level (e.g., behaviors, carcinogenic exposures, socioeconomic factors, and psychologic responses); and (iii) biologic level (e.g., cellular biomarkers and inherited susceptibility variants). Prior multilevel approaches tend to focus on social and environmental hypotheses, and are thus limited in their ability to integrate biologic factors into a multilevel framework. This limited integration may be related to the limited translation of research findings into the clinic. We propose a "Multi-level Biologic and Social Integrative Construct" (MBASIC) to integrate macroenvironment and individual factors with biology. The goal of this framework is to help researchers identify relationships among factors that may be involved in the multifactorial, complex nature of cancer etiology, to aid in appropriate study design, to guide the development of statistical or mechanistic models to study these relationships, and to position the results of these studies for improved intervention, translation, and implementation. MBASIC allows researchers from diverse fields to develop hypotheses of interest under a common conceptual framework, to guide transdisciplinary collaborations, and to optimize the value of multilevel studies for clinical and public health activities.

A comprehensive multimodal pain treatment reduces opioid consumption after multilevel spine surgery

DEFF Research Database (Denmark)

Mathiesen, Ole; Dahl, Benny; Thomsen, Berit A

2013-01-01

and postoperative nausea and vomiting (PONV) treatment protocol would improve pain treatment in this population. METHODS: A new regimen with acetaminophen, NSAIDs, gabapentin, S-ketamine, dexamethasone, ondansetron and epidural local anesthetic infusion or patient controlled analgesia with morphine, was introduced......PURPOSE: Major spine surgery with multilevel instrumentation is followed by large amount of opioid consumption, significant pain and difficult mobilization in a population of predominantly chronic pain patients. This case-control study investigated if a standardized comprehensive pain...... and dizziness on POD 1-6. CONCLUSIONS: In this study of patients scheduled for multilevel spine surgery, it was demonstrated that compared to a historic group of patients receiving usual care, a comprehensive and standardized multimodal pain and PONV protocol significantly reduced opioid consumption, improved...

Liver transplantation in HIV-positive patients: the position of the Brazilian groups.

Science.gov (United States)

Brandão, Ajacio Bandeira de Mello; Mariante-Neto, Guilherme

2005-01-01

Patients infected with the human immunodeficiency virus (HIV) have generally been excluded from consideration for liver transplantation. Recent advances in the management and prognosis of these patients suggest that this policy must be reevaluated. To identify the current position of Brazilian transplant centers concerning liver transplantation in asymptomatic HIV-infected patients with end-stage liver disease. A structured questionnaire was submitted by e-mail to Brazilian groups who perform liver transplantation and were active in late 2003, according to the Brazilian Association of Organ Transplantation. Of the 53 active groups, 30 e-mail addresses have been found of professionals working in 41 of these groups. Twenty-one responses (70%) were obtained. Most of the professionals (62%) reported that they do not include HIV-infected patients in waiting lists for transplants, primarily on account of the limited world experience. They also reported, however, that this issue will soon be discussed by the group. Those who accept these patients usually follow the guidelines provided by the literature: patients must fulfill the same inclusion criteria as the other patients with end-stage liver diseases, present low or undetectable HIV viral load, and a CD4 count above 250/mm3. They reported that there are 10 HIV-infected patients in waiting list and that only one patient has received a liver transplant in the country. Most centers do not accept in waiting lists for liver transplantation patients with HIV infection, even asymptomatic ones. However, advances in the management of HIV-infected patients suggest that this policy must be reevaluated. In Brazil, there is practically no experience in liver transplantation in HIV-positive patients.

A 2 x 2 Taxonomy of Multilevel Latent Contextual Models: Accuracy-Bias Trade-Offs in Full and Partial Error Correction Models

Science.gov (United States)

Ludtke, Oliver; Marsh, Herbert W.; Robitzsch, Alexander; Trautwein, Ulrich

2011-01-01

In multilevel modeling, group-level variables (L2) for assessing contextual effects are frequently generated by aggregating variables from a lower level (L1). A major problem of contextual analyses in the social sciences is that there is no error-free measurement of constructs. In the present article, 2 types of error occurring in multilevel data…

Multi-level converter with auxiliary resonant-commutated pole

NARCIS (Netherlands)

Dijkhuizen, F.R.; Duarte, J.L.; Groningen, van W.D.H.

1998-01-01

The family of multi-level power converters offers advantages for high-power, high-voltage systems. A multi-level nested-cell structure has the attractive feature of static and dynamic voltage sharing among the switches. This is achieved by using clamping capacitors (floating capacitors) rather than

Explaining ethnic polarization over attitudes towards minority rights in Eastern Europe : a multilevel analysis

NARCIS (Netherlands)

Evans, Geoffrey; Need, Ariana

2002-01-01

This paper examines divisions between majority and minority ethnic groups over attitudes towards minority rights in 13 East European societies. Using national sample surveys and multilevel models, we test the effectiveness of competing explanations of ethnic polarization in attitudes towards

Multilevel Fast Multipole Method for Higher Order Discretizations

DEFF Research Database (Denmark)

Borries, Oscar Peter; Meincke, Peter; Jorgensen, Erik

2014-01-01

The multi-level fast multipole method (MLFMM) for a higher order (HO) discretization is demonstrated on high-frequency (HF) problems, illustrating for the first time how an efficient MLFMM for HO can be achieved even for very large groups. Applying several novel ideas, beneficial to both lower...... order and higher order discretizations, results from a low-memory, high-speed MLFMM implementation of a HO hierarchical discretization are shown. These results challenge the general view that the benefits of HO and HF-MLFMM cannot be combined....

Streaming, Tracking and Reading Achievement: A Multilevel Analysis of Students in 40 Countries

Science.gov (United States)

Chiu, Ming Ming; Chow, Bonnie Wing-Yin; Joh, Sung Wook

2017-01-01

Grouping similar students together within schools ("streaming") or classrooms ("tracking") based on past literacy skills (reported by parents), family socioeconomic status (SES) or reading attitudes might affect their reading achievement. Our multilevel analysis of the reading tests of 208,057 fourth-grade students across 40…

Parental attributions for positive behaviours in children with autism spectrum disorder.

Science.gov (United States)

Bussanich, P; Hartley, S L; Bolt, D

2017-07-01

The present study examined parental attributions for positive child behaviour in children with Autism Spectrum Disorder (ASD) and their association with parent outcomes. In total, 175 couples who had a child with ASD (5-12 years) completed measures about the child's positive behaviour, ASD symptoms, functional skills and negative behaviour problems, and their own positive and negative affect and closeness in the parent-child relationship. A comparison group of 170 couples who had a child without a neurodevelopmental disability also completed measures. Dyadic multilevel models were conducted. Parents of children with ASD believed that their child's positive behaviour was due to factors less internal to the child, less stable and less controllable by the child than the comparison group. Beliefs about stability were associated with closeness in the parent-child relationship. Child age and level of impairment and parent education were associated with parental attributions. Interventions that alter parental attributions may offer pathways to increase closeness in the parent-child relationship. © 2017 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

A multilevel evolutionary framework for sustainability analysis

Directory of Open Access Journals (Sweden)

Timothy M. Waring

2015-06-01

Full Text Available Sustainability theory can help achieve desirable social-ecological states by generalizing lessons across contexts and improving the design of sustainability interventions. To accomplish these goals, we argue that theory in sustainability science must (1 explain the emergence and persistence of social-ecological states, (2 account for endogenous cultural change, (3 incorporate cooperation dynamics, and (4 address the complexities of multilevel social-ecological interactions. We suggest that cultural evolutionary theory broadly, and cultural multilevel selection in particular, can improve on these fronts. We outline a multilevel evolutionary framework for describing social-ecological change and detail how multilevel cooperative dynamics can determine outcomes in environmental dilemmas. We show how this framework complements existing sustainability frameworks with a description of the emergence and persistence of sustainable institutions and behavior, a means to generalize causal patterns across social-ecological contexts, and a heuristic for designing and evaluating effective sustainability interventions. We support these assertions with case examples from developed and developing countries in which we track cooperative change at multiple levels of social organization as they impact social-ecological outcomes. Finally, we make suggestions for further theoretical development, empirical testing, and application.

Multilevel sparse functional principal component analysis.

Science.gov (United States)

Di, Chongzhi; Crainiceanu, Ciprian M; Jank, Wolfgang S

2014-01-29

We consider analysis of sparsely sampled multilevel functional data, where the basic observational unit is a function and data have a natural hierarchy of basic units. An example is when functions are recorded at multiple visits for each subject. Multilevel functional principal component analysis (MFPCA; Di et al. 2009) was proposed for such data when functions are densely recorded. Here we consider the case when functions are sparsely sampled and may contain only a few observations per function. We exploit the multilevel structure of covariance operators and achieve data reduction by principal component decompositions at both between and within subject levels. We address inherent methodological differences in the sparse sampling context to: 1) estimate the covariance operators; 2) estimate the functional principal component scores; 3) predict the underlying curves. Through simulations the proposed method is able to discover dominating modes of variations and reconstruct underlying curves well even in sparse settings. Our approach is illustrated by two applications, the Sleep Heart Health Study and eBay auctions.

Multi-level trellis coded modulation and multi-stage decoding

Science.gov (United States)

Costello, Daniel J., Jr.; Wu, Jiantian; Lin, Shu

1990-01-01

Several constructions for multi-level trellis codes are presented and many codes with better performance than previously known codes are found. These codes provide a flexible trade-off between coding gain, decoding complexity, and decoding delay. New multi-level trellis coded modulation schemes using generalized set partitioning methods are developed for Quadrature Amplitude Modulation (QAM) and Phase Shift Keying (PSK) signal sets. New rotationally invariant multi-level trellis codes which can be combined with differential encoding to resolve phase ambiguity are presented.

Proposed Novel Multiphase-Multilevel Inverter Configuration for Open-End Winding Loads

DEFF Research Database (Denmark)

Padamanaban, Sanjeevi Kumar; Wheeler, Patrick; Blaabjerg, Frede

2016-01-01

This paper presents a new multiphase-multilevel inverter configuration for open-winding loads and suitable for medium power (low-voltage/high-current) applications such as `More Electric Aircraft'. Modular structure comprised of standard dual three-phase voltage source inverter (VSI) along with one...... is developed in this work and overcomes the complexity of standard space vector modulations, easy for real implementation purposes in digital processors. Proposed six-phase multilevel inverter configuration generates multilevel outputs with benefit in comprises with standard multilevel inverter topologies...

Finite Mixture Multilevel Multidimensional Ordinal IRT Models for Large Scale Cross-Cultural Research

Science.gov (United States)

de Jong, Martijn G.; Steenkamp, Jan-Benedict E. M.

2010-01-01

We present a class of finite mixture multilevel multidimensional ordinal IRT models for large scale cross-cultural research. Our model is proposed for confirmatory research settings. Our prior for item parameters is a mixture distribution to accommodate situations where different groups of countries have different measurement operations, while…

Long bone reconstruction using multilevel lengthening of bone defect fragments.

Science.gov (United States)

Borzunov, Dmitry Y

2012-08-01

This paper presents experimental findings to substantiate the use of multilevel bone fragment lengthening for managing extensive long bone defects caused by diverse aetiologies and shows its clinical introduction which could provide a solution for the problem of reducing the total treatment time. Both experimental and clinical multilevel lengthening to bridge bone defect gaps was performed with the use of the Ilizarov method only. The experimental findings and clinical outcomes showed that multilevel defect fragment lengthening could provide sufficient bone formation and reduction of the total osteosynthesis time in one stage as compared to traditional Ilizarov bone transport. The method of multilevel regeneration enabled management of critical-size defects that measured on average 13.5 ± 0.7 cm in 78 patients. The experimental and clinical results proved the efficiency of the Ilizarov non-free multilevel bone plasty that can be recommended for practical use.

Synchronous Control of Modular Multilevel Converters

DEFF Research Database (Denmark)

Oleschuk, Valentin; Blaabjerg, Frede; Bose, Bimal K.

2002-01-01

A novel method of direct synchronous pulsewidth modulation (PWM) is applied for control of modular multilevel converters consisting from three standard triphase inverter modules along with an 0.33 p.u. output transformer. The proposed method provides synchronisation of the voltage waveforms...... for each module and the composed voltage at the output of the converter. Multilevel output voltage of the converter has quarter-wave symmetry during the whole range including the zone of overmodulation. Both continuous and discontinuous versions of synchronous PWM, based on vector approach...

Towards the development of multilevel-multiagent diagnostic aids

International Nuclear Information System (INIS)

Stratton, R.C.; Jarrell, D.B.

1991-10-01

Presented here is our methodology for developing automated aids for diagnosing faults in complex systems. We have designed these aids as multilevel-multiagent diagnostic aids based on principles that should be generally applicable to any complex system. In this methodology, ''multilevel'' refers to information models described at successful levels of abstraction that are tied together in such a way that reasoning is directed to the appropriate level as determined by the problem solving requirements. The concept of ''multiagent'' refers to the method of information processing within the multilevel model network; each model in the network is an independent information processor, i.e., an intelligent agent. 19 refs., 15 figs., 9 tabs

The learner’s perspective in GP teaching practices with multi-level learners: a qualitative study

Science.gov (United States)

2014-01-01

Background Medical students, junior hospital doctors on rotation and general practice (GP) registrars are undertaking their training in clinical general practices in increasing numbers in Australia. Some practices have four levels of learner. This study aimed to explore how multi-level teaching (also called vertical integration of GP education and training) is occurring in clinical general practice and the impact of such teaching on the learner. Methods A qualitative research methodology was used with face-to-face, semi-structured interviews of medical students, junior hospital doctors, GP registrars and GP teachers in eight training practices in the region that taught all levels of learners. Interviews were audio-recorded and transcribed. Qualitative analysis was conducted using thematic analysis techniques aided by the use of the software package N-Vivo 9. Primary themes were identified and categorised by the co-investigators. Results 52 interviews were completed and analysed. Themes were identified relating to both the practice learning environment and teaching methods used. A practice environment where there is a strong teaching culture, enjoyment of learning, and flexible learning methods, as well as learning spaces and organised teaching arrangements, all contribute to positive learning from a learners’ perspective. Learners identified a number of innovative teaching methods and viewed them as positive. These included multi-level learner group tutorials in the practice, being taught by a team of teachers, including GP registrars and other health professionals, and access to a supernumerary GP supervisor (also termed “GP consultant teacher”). Other teaching methods that were viewed positively were parallel consulting, informal learning and rural hospital context integrated learning. Conclusions Vertical integration of GP education and training generally impacted positively on all levels of learner. This research has provided further evidence about the

Bayesian Optimal Experimental Design Using Multilevel Monte Carlo

KAUST Repository

Ben Issaid, Chaouki; Long, Quan; Scavino, Marco; Tempone, Raul

2015-01-01

Experimental design is very important since experiments are often resource-exhaustive and time-consuming. We carry out experimental design in the Bayesian framework. To measure the amount of information, which can be extracted from the data in an experiment, we use the expected information gain as the utility function, which specifically is the expected logarithmic ratio between the posterior and prior distributions. Optimizing this utility function enables us to design experiments that yield the most informative data for our purpose. One of the major difficulties in evaluating the expected information gain is that the integral is nested and can be high dimensional. We propose using Multilevel Monte Carlo techniques to accelerate the computation of the nested high dimensional integral. The advantages are twofold. First, the Multilevel Monte Carlo can significantly reduce the cost of the nested integral for a given tolerance, by using an optimal sample distribution among different sample averages of the inner integrals. Second, the Multilevel Monte Carlo method imposes less assumptions, such as the concentration of measures, required by Laplace method. We test our Multilevel Monte Carlo technique using a numerical example on the design of sensor deployment for a Darcy flow problem governed by one dimensional Laplace equation. We also compare the performance of the Multilevel Monte Carlo, Laplace approximation and direct double loop Monte Carlo.

Bayesian Optimal Experimental Design Using Multilevel Monte Carlo

KAUST Repository

Ben Issaid, Chaouki

2015-01-07

Experimental design is very important since experiments are often resource-exhaustive and time-consuming. We carry out experimental design in the Bayesian framework. To measure the amount of information, which can be extracted from the data in an experiment, we use the expected information gain as the utility function, which specifically is the expected logarithmic ratio between the posterior and prior distributions. Optimizing this utility function enables us to design experiments that yield the most informative data for our purpose. One of the major difficulties in evaluating the expected information gain is that the integral is nested and can be high dimensional. We propose using Multilevel Monte Carlo techniques to accelerate the computation of the nested high dimensional integral. The advantages are twofold. First, the Multilevel Monte Carlo can significantly reduce the cost of the nested integral for a given tolerance, by using an optimal sample distribution among different sample averages of the inner integrals. Second, the Multilevel Monte Carlo method imposes less assumptions, such as the concentration of measures, required by Laplace method. We test our Multilevel Monte Carlo technique using a numerical example on the design of sensor deployment for a Darcy flow problem governed by one dimensional Laplace equation. We also compare the performance of the Multilevel Monte Carlo, Laplace approximation and direct double loop Monte Carlo.

Does Group-Level Commitment Predict Employee Well-Being?: A Prospective Analysis.

Science.gov (United States)

Clausen, Thomas; Christensen, Karl Bang; Nielsen, Karina

2015-11-01

To investigate the links between group-level affective organizational commitment (AOC) and individual-level psychological well-being, self-reported sickness absence, and sleep disturbances. A total of 5085 care workers from 301 workgroups in the Danish eldercare services participated in both waves of the study (T1 [2005] and T2 [2006]). The three outcomes were analyzed using linear multilevel regression analysis, multilevel Poisson regression analysis, and multilevel logistic regression analysis, respectively. Group-level AOC (T1) significantly predicted individual-level psychological well-being, self-reported sickness absence, and sleep disturbances (T2). The association between group-level AOC (T1) and psychological well-being (T2) was fully mediated by individual-level AOC (T1), and the associations between group-level AOC (T1) and self-reported sickness absence and sleep disturbances (T2) were partially mediated by individual-level AOC (T1). Group-level AOC is an important predictor of employee well-being in contemporary health care organizations.

A multi-level approach of evaluating crew resource management training: a laboratory-based study examining communication skills as a function of team congruence.

Science.gov (United States)

Sauer, J; Darioly, A; Mast, M Schmid; Schmid, P C; Bischof, N

2010-11-01

The article proposes a multi-level approach for evaluating communication skills training (CST) as an important element of crew resource management (CRM) training. Within this methodological framework, the present work examined the effectiveness of CST in matching or mismatching team compositions with regard to hierarchical status and competence. There is little experimental research that evaluated the effectiveness of CRM training at multiple levels (i.e. reaction, learning, behaviour) and in teams composed of members of different status and competence. An experiment with a two (CST: with vs. without) by two (competence/hierarchical status: congruent vs. incongruent) design was carried out. A total of 64 participants were trained for 2.5 h on a simulated process control environment, with the experimental group being given 45 min of training on receptiveness and influencing skills. Prior to the 1-h experimental session, participants were assigned to two-person teams. The results showed overall support for the use of such a multi-level approach of training evaluation. Stronger positive effects of CST were found for subjective measures than for objective performance measures. STATEMENT OF RELEVANCE: This work provides some guidance for the use of a multi-level evaluation of CRM training. It also emphasises the need to collect objective performance data for training evaluation in addition to subjective measures with a view to gain a more accurate picture of the benefits of such training approaches.

Intermediate and advanced topics in multilevel logistic regression analysis.

Science.gov (United States)

Austin, Peter C; Merlo, Juan

2017-09-10

Multilevel data occur frequently in health services, population and public health, and epidemiologic research. In such research, binary outcomes are common. Multilevel logistic regression models allow one to account for the clustering of subjects within clusters of higher-level units when estimating the effect of subject and cluster characteristics on subject outcomes. A search of the PubMed database demonstrated that the use of multilevel or hierarchical regression models is increasing rapidly. However, our impression is that many analysts simply use multilevel regression models to account for the nuisance of within-cluster homogeneity that is induced by clustering. In this article, we describe a suite of analyses that can complement the fitting of multilevel logistic regression models. These ancillary analyses permit analysts to estimate the marginal or population-average effect of covariates measured at the subject and cluster level, in contrast to the within-cluster or cluster-specific effects arising from the original multilevel logistic regression model. We describe the interval odds ratio and the proportion of opposed odds ratios, which are summary measures of effect for cluster-level covariates. We describe the variance partition coefficient and the median odds ratio which are measures of components of variance and heterogeneity in outcomes. These measures allow one to quantify the magnitude of the general contextual effect. We describe an R 2 measure that allows analysts to quantify the proportion of variation explained by different multilevel logistic regression models. We illustrate the application and interpretation of these measures by analyzing mortality in patients hospitalized with a diagnosis of acute myocardial infarction. © 2017 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. © 2017 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

Federalism and multilevel governance

NARCIS (Netherlands)

van der Wusten, H.; Agnew, J.; Mamadouh, V.; Secor, A.J.; Sharp, J.

2015-01-01

Federalism and multilevel governance both emphasize polycentricity in governing arrangements. With their different intellectual pedigrees, these concepts are discussed in two separate sections. Fragments are now increasingly mixed up in hybrid forms of governance that also encompass originally

Ethnic Diversity, Inter-group Attitudes and Countervailing Pathways of Positive and Negative Inter-group Contact: An Analysis Across Workplaces and Neighbourhoods.

Science.gov (United States)

Laurence, James; Schmid, Katharina; Hewstone, Miles

2018-01-01

This study advances the current literature investigating the relationship between contextual out-group exposure, inter-group attitudes and the role of inter-group contact. Firstly, it introduces the concept of contact-valence into this relationship; that is, whether contact is experienced positively or negatively. Secondly, it presents a comparative analysis of how processes of out-group exposure and frequency of (valenced) contact affect prejudice across both neighbourhoods and workplaces. Applying path analysis modelling to a nationally-representative sample of white British individuals in England, we demonstrate, across both contexts, that increasing out-group exposure is associated with higher rates of both positively- and negatively-valenced contact. This results in exposure exhibiting both positive and negative indirect associations with prejudice via more frequent inter-group mixing. These countervailing contact-pathways help explain how out-group exposure is associated with inter-group attitudes. In neighbourhoods, increasing numbers of individuals experiencing positive-contact suppress an otherwise negative effect of neighbourhood diversity (driven partly by increasing numbers of individuals reporting negative contact). Across workplaces the effect differs such that increasing numbers of individuals experiencing negative-contact suppress an otherwise positive effect of workplace diversity (driven largely by increasing numbers of individuals experiencing positive contact).

Members' needs, intragroup conflict, and group performance.

Science.gov (United States)

Chun, Jinseok S; Choi, Jin Nam

2014-05-01

Focusing on "what people want in their group" as a critical antecedent of intragroup conflict, the present study theorizes and empirically investigates the relationships among the psychological needs of group members, intragroup conflict, and group performance. It attends to the within-group average and dispersion of members' psychological needs and examines the effects stemming from group composition of needs on multiple types of conflict. The analyses based on multisource data from 145 organizational teams revealed significant relationships between the groups' composition with respect to the members' need for achievement and task conflict, need for affiliation and relationship conflict, and need for power and status conflict. Some of these relationships were moderated by open communication among members. The analyses also demonstrated that when the 3 types of conflict were considered together, task conflict was a positive predictor of group performance, whereas relationship conflict was a negative predictor. The findings highlight the motivational aspects of intragroup conflict, revealing the multilevel dynamics of the psychological needs in social settings. (c) 2014 APA, all rights reserved.

Multilevel Image Segmentation Based on an Improved Firefly Algorithm

Directory of Open Access Journals (Sweden)

Kai Chen

2016-01-01

Full Text Available Multilevel image segmentation is time-consuming and involves large computation. The firefly algorithm has been applied to enhancing the efficiency of multilevel image segmentation. However, in some cases, firefly algorithm is easily trapped into local optima. In this paper, an improved firefly algorithm (IFA is proposed to search multilevel thresholds. In IFA, in order to help fireflies escape from local optima and accelerate the convergence, two strategies (i.e., diversity enhancing strategy with Cauchy mutation and neighborhood strategy are proposed and adaptively chosen according to different stagnation stations. The proposed IFA is compared with three benchmark optimal algorithms, that is, Darwinian particle swarm optimization, hybrid differential evolution optimization, and firefly algorithm. The experimental results show that the proposed method can efficiently segment multilevel images and obtain better performance than the other three methods.

Integrity Based Access Control Model for Multilevel XML Document

Institute of Scientific and Technical Information of China (English)

HONG Fan; FENG Xue-bin; HUANO Zhi; ZHENG Ming-hui

2008-01-01

XML's increasing popularity highlights the security demand for XML documents. A mandatory access control model for XML document is presented on the basis of investigation of the function dependency of XML documents and discussion of the integrity properties of multilevel XML document. Then, the algorithms for decomposition/recovery multilevel XML document into/from single level document are given, and the manipulation rules for typical operations of XQuery and XUpdate: QUERY, INSERT,UPDATE, and REMOVE, are elaborated. The multilevel XML document access model can meet the requirement of sensitive information processing application.

Motivating Proteges' Personal Learning in Teams: A Multilevel Investigation of Autonomy Support and Autonomy Orientation

Science.gov (United States)

Liu, Dong; Fu, Ping-ping

2011-01-01

This study examined the roles of 3 multilevel motivational predictors in proteges' personal learning in teams: an autonomy-supportive team climate, mentors' autonomy support, and proteges' autonomy orientation. The authors followed 305 proteges in 58 teams for 12 weeks and found that all 3 predictors were positively related to the proteges'…

Multilevel- marketing v České republice

OpenAIRE

Prudičová, Petra

2009-01-01

Graduation Theses concerns an analysis and evaluation, of how a multi-level marketing, functions in the Czech Republic. Explaining its ideals and principals, while it theoretically applies on a specific company, which is involved with multi-level marketing. The target is to introduce such system in an objective way and evaluate it in practice.

Web Syndication in a Multilevel Security Environment

Science.gov (United States)

2012-03-01

Group LAMP Linux, Apache, MySQL and PHP LAN Local Area Network MAC Mandatory Access Control MILS Multiple Independent Levels of Security MLS Multilevel...Reader [35] Section 1.4.3 – X X X X X FeedShow [36] Section 1.4.3 – X X X X feed on feeds [37] Section 1.4.3 GPL PHP 4.3.2+, MySQL – X X / Tiny Tiny RSS...38] Section 1.4.3 GPL PHP 5+, MySQL /Postgres – X X X X – zFeeder [39] Section 1.4.3 GPL PHP 4.2+ – X X – / lylina [40] Section 1.4.3 GPL PHP 5.2

Self-balanced modulation and magnetic rebalancing method for parallel multilevel inverters

Science.gov (United States)

Li, Hui; Shi, Yanjun

2017-11-28

A self-balanced modulation method and a closed-loop magnetic flux rebalancing control method for parallel multilevel inverters. The combination of the two methods provides for balancing of the magnetic flux of the inter-cell transformers (ICTs) of the parallel multilevel inverters without deteriorating the quality of the output voltage. In various embodiments a parallel multi-level inverter modulator is provide including a multi-channel comparator to generate a multiplexed digitized ideal waveform for a parallel multi-level inverter and a finite state machine (FSM) module coupled to the parallel multi-channel comparator, the FSM module to receive the multiplexed digitized ideal waveform and to generate a pulse width modulated gate-drive signal for each switching device of the parallel multi-level inverter. The system and method provides for optimization of the output voltage spectrum without influence the magnetic balancing.

Realist explanatory theory building method for social epidemiology: a protocol for a mixed method multilevel study of neighbourhood context and postnatal depression.

Science.gov (United States)

Eastwood, John G; Jalaludin, Bin B; Kemp, Lynn A

2014-01-01

A recent criticism of social epidemiological studies, and multi-level studies in particular has been a paucity of theory. We will present here the protocol for a study that aims to build a theory of the social epidemiology of maternal depression. We use a critical realist approach which is trans-disciplinary, encompassing both quantitative and qualitative traditions, and that assumes both ontological and hierarchical stratification of reality. We describe a critical realist Explanatory Theory Building Method comprising of an: 1) emergent phase, 2) construction phase, and 3) confirmatory phase. A concurrent triangulated mixed method multilevel cross-sectional study design is described. The Emergent Phase uses: interviews, focus groups, exploratory data analysis, exploratory factor analysis, regression, and multilevel Bayesian spatial data analysis to detect and describe phenomena. Abductive and retroductive reasoning will be applied to: categorical principal component analysis, exploratory factor analysis, regression, coding of concepts and categories, constant comparative analysis, drawing of conceptual networks, and situational analysis to generate theoretical concepts. The Theory Construction Phase will include: 1) defining stratified levels; 2) analytic resolution; 3) abductive reasoning; 4) comparative analysis (triangulation); 5) retroduction; 6) postulate and proposition development; 7) comparison and assessment of theories; and 8) conceptual frameworks and model development. The strength of the critical realist methodology described is the extent to which this paradigm is able to support the epistemological, ontological, axiological, methodological and rhetorical positions of both quantitative and qualitative research in the field of social epidemiology. The extensive multilevel Bayesian studies, intensive qualitative studies, latent variable theory, abductive triangulation, and Inference to Best Explanation provide a strong foundation for Theory

Multiple imputation by chained equations for systematically and sporadically missing multilevel data.

Science.gov (United States)

Resche-Rigon, Matthieu; White, Ian R

2018-06-01

In multilevel settings such as individual participant data meta-analysis, a variable is 'systematically missing' if it is wholly missing in some clusters and 'sporadically missing' if it is partly missing in some clusters. Previously proposed methods to impute incomplete multilevel data handle either systematically or sporadically missing data, but frequently both patterns are observed. We describe a new multiple imputation by chained equations (MICE) algorithm for multilevel data with arbitrary patterns of systematically and sporadically missing variables. The algorithm is described for multilevel normal data but can easily be extended for other variable types. We first propose two methods for imputing a single incomplete variable: an extension of an existing method and a new two-stage method which conveniently allows for heteroscedastic data. We then discuss the difficulties of imputing missing values in several variables in multilevel data using MICE, and show that even the simplest joint multilevel model implies conditional models which involve cluster means and heteroscedasticity. However, a simulation study finds that the proposed methods can be successfully combined in a multilevel MICE procedure, even when cluster means are not included in the imputation models.

Multilevel selection in a resource-based model

Science.gov (United States)

Ferreira, Fernando Fagundes; Campos, Paulo R. A.

2013-07-01

In the present work we investigate the emergence of cooperation in a multilevel selection model that assumes limiting resources. Following the work by R. J. Requejo and J. Camacho [Phys. Rev. Lett.0031-900710.1103/PhysRevLett.108.038701 108, 038701 (2012)], the interaction among individuals is initially ruled by a prisoner's dilemma (PD) game. The payoff matrix may change, influenced by the resource availability, and hence may also evolve to a non-PD game. Furthermore, one assumes that the population is divided into groups, whose local dynamics is driven by the payoff matrix, whereas an intergroup competition results from the nonuniformity of the growth rate of groups. We study the probability that a single cooperator can invade and establish in a population initially dominated by defectors. Cooperation is strongly favored when group sizes are small. We observe the existence of a critical group size beyond which cooperation becomes counterselected. Although the critical size depends on the parameters of the model, it is seen that a saturation value for the critical group size is achieved. The results conform to the thought that the evolutionary history of life repeatedly involved transitions from smaller selective units to larger selective units.

The Relationship of Repeated Technical Assistance Support Visits to the Delivery of Positive Health, Dignity, and Prevention (PHDP) Messages by Healthcare Providers in Mozambique: A Longitudinal Multilevel Analysis.

Science.gov (United States)

Gutin, Sarah A; Amico, K Rivet; Hunguana, Elsa; Munguambe, António Orlando; Rose, Carol Dawson

Positive health, dignity, and prevention (PHDP) is Mozambique's strategy to engage clinicians in the delivery of prevention messages to their HIV-positive clients. This national implementation strategy uses provider trainings on offering key messages and focuses on intervening on 9 evidence-based risk reduction areas. We investigated the impact of longitudinal technical assistance (TA) as an addition to this basic training. We followed 153 healthcare providers in 5 Mozambican provinces over 6 months to evaluate the impact of on-site, observation-based TA on PHDP implementation. Longitudinal multilevel models were estimated to model change in PHDP message delivery over time among individual providers. With each additional TA visit, providers delivered about 1 additional PHDP message ( P < .001); clinicians and nonclinicians started at about the same baseline level, but clinicians improved more quickly ( P = .004). Message delivery varied by practice sector; maternal and child health sectors outperformed other sectors. Longitudinal TA helped reach the programmatic goals of the PHDP program in Mozambique.

Multilevel structural equation models for assessing moderation within and across levels of analysis.

Science.gov (United States)

Preacher, Kristopher J; Zhang, Zhen; Zyphur, Michael J

2016-06-01

Social scientists are increasingly interested in multilevel hypotheses, data, and statistical models as well as moderation or interactions among predictors. The result is a focus on hypotheses and tests of multilevel moderation within and across levels of analysis. Unfortunately, existing approaches to multilevel moderation have a variety of shortcomings, including conflated effects across levels of analysis and bias due to using observed cluster averages instead of latent variables (i.e., "random intercepts") to represent higher-level constructs. To overcome these problems and elucidate the nature of multilevel moderation effects, we introduce a multilevel structural equation modeling (MSEM) logic that clarifies the nature of the problems with existing practices and remedies them with latent variable interactions. This remedy uses random coefficients and/or latent moderated structural equations (LMS) for unbiased tests of multilevel moderation. We describe our approach and provide an example using the publicly available High School and Beyond data with Mplus syntax in Appendix. Our MSEM method eliminates problems of conflated multilevel effects and reduces bias in parameter estimates while offering a coherent framework for conceptualizing and testing multilevel moderation effects. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The Association of Workplace Social Capital With Work Engagement of Employees in Health Care Settings: A Multilevel Cross-Sectional Analysis.

Science.gov (United States)

Fujita, Sumiko; Kawakami, Norito; Ando, Emiko; Inoue, Akiomi; Tsuno, Kanami; Kurioka, Sumiko; Kawachi, Ichiro

2016-03-01

The aim of the study was to examine the cross-sectional multilevel association between unit-level workplace social capital and individual-level work engagement among employees in health care settings. The data were collected from employees of a Japanese health care corporation using a questionnaire. The analyses were limited to 440 respondents from 35 units comprising five or more respondents per unit. Unit-level workplace social capital was calculated as an average score of the Workplace Social Capital Scale for each unit. Multilevel regression analysis with a random intercept model was conducted. After adjusting for demographic variables, unit-level workplace social capital was significantly and positively associated with respondents' work engagement (P capital (P capital might exert a positive contextual effect on work engagement of employees in health care settings.

Serving the army as secretaries: intersectionality, multi-level contract and subjective experience of citizenship.

Science.gov (United States)

Lomsky-Feder, Edna; Sasson-Levy, Orna

2015-03-01

With the growing elusiveness of the state apparatus in late modernity, military service is one of the last institutions to be clearly identified with the state, its ideologies and its policies. Therefore, negotiations between the military and its recruits produce acting subjects of citizenship with long-lasting consequences. Arguing that these negotiations are regulated by multi-level (civic, group, and individual) contracts, we explore the various meanings that these contracts obtain at the intersectionality of gender, class, and ethnicity; and examine how they shape the subjective experience of soldierhood and citizenship. More particularly, we analyse the meaning of military service in the retrospective life stories of Israeli Jewish women from various ethno-class backgrounds who served as army secretaries - a low-status, feminine gender-typed occupation within a hyper-masculine organization. Findings reveal that for women of the lower class, the organizing cultural schema of the multi-level contract is that of achieving respectability through military service, which means being included in the national collective. Conversely, for middle-class women, it is the sense of entitlement that shapes their contract with the military, which they expect to signify and maintain their privileged status. Thus, while for the lower class, the multi-level contract is about inclusion within the boundaries of the national collective, for the dominant groups, this contract is about reproducing social class hierarchies within national boundaries. © London School of Economics and Political Science 2014.

Effect of age on the perioperative and radiographic complications of multilevel cervicothoracic spinal fusions.

Science.gov (United States)

Cloyd, Jordan M; Acosta, Frank L; Ames, Christopher P

2008-12-15

Retrospective review. To investigate the effect of age on the perioperative and radiographic complications associated with multilevel (>or=5) fusion of the cervicothoracic spine. Although the elderly comprise a substantial proportion of patients presenting with complex spinal pathology necessitating multilevel procedures across the cervical and cervicothoracic spine, the risk of perioperative and radiographic complications after these procedures is unknown. Between 2000 and 2007, 58 patients 65 years of age or older at a single institution underwent instrumented cervicothoracic spinal fusion of at least 5 levels. Fifty-eight patients under the age of 65 from the same time period served as a control group. A retrospective review of all hospital records, operative reports, radiographs, and clinic notes was conducted. Complications were classified as intraoperative, major and minor postoperative, and need for revision surgery. Flexion-extension radiographs were examined at discharge, 1.5, 6, 12 months, and then yearly, thereafter to evaluate fusion status and instrumentation-related complications. Principal diagnoses included spondylostenosis, malignancy, vertebral fracture, and osteomyelitis. Both groups were similar in number of levels fused (elderly, 6.7 +/- 2.1; control, 6.3 +/- 1.7) and circumferential procedures (27 vs. 28), respectively. There were no significant differences in operative time, blood loss, or length of hospital stay. Rates of intraoperative (5.2% vs. 3.4%), major (20.7% vs. 17.2%) and minor postoperative complications (27.6% vs. 22.4%), and reoperation (8.6% vs. 8.6%) were similar between the 2 groups. Utilization of a combined anterior-posterior fusion was associated with increased perioperative complications in the elderly on univariate but not multivariate analyses. Radiographic evidence of fusion was also comparable between the 2 groups. Perioperative complication rates of multilevel (>or=5) cervicothoracic spinal fusion in the elderly are

Multi-level iteration optimization for diffusive critical calculation

International Nuclear Information System (INIS)

Li Yunzhao; Wu Hongchun; Cao Liangzhi; Zheng Youqi

2013-01-01

In nuclear reactor core neutron diffusion calculation, there are usually at least three levels of iterations, namely the fission source iteration, the multi-group scattering source iteration and the within-group iteration. Unnecessary calculations occur if the inner iterations are converged extremely tight. But the convergence of the outer iteration may be affected if the inner ones are converged insufficiently tight. Thus, a common scheme suit for most of the problems was proposed in this work to automatically find the optimized settings. The basic idea is to optimize the relative error tolerance of the inner iteration based on the corresponding convergence rate of the outer iteration. Numerical results of a typical thermal neutron reactor core problem and a fast neutron reactor core problem demonstrate the effectiveness of this algorithm in the variational nodal method code NODAL with the Gauss-Seidel left preconditioned multi-group GMRES algorithm. The multi-level iteration optimization scheme reduces the number of multi-group and within-group iterations respectively by a factor of about 1-2 and 5-21. (authors)

Small Group Multitasking in Literature Classes

Science.gov (United States)

Baurain, Bradley

2007-01-01

Faced with the challenge of teaching American literature to large, multilevel classes in Vietnam, the writer developed a flexible small group framework called "multitasking". "Multitasking" sets up stable task categories which rotate among small groups from lesson to lesson. This framework enabled students to work cooperatively…

On multi-level thinking and scientific understanding

Science.gov (United States)

McIntyre, Michael Edgeworth

2017-10-01

Professor Duzheng YE's name has been familiar to me ever since my postdoctoral years at MIT with Professors Jule CHARNEY and Norman PHILLIPS, back in the late 1960s. I had the enormous pleasure of meeting Professor YE personally in 1992 in Beijing. His concern to promote the very best science and to use it well, and his thinking on multi-level orderly human activities, reminds me not only of the communication skills we need as scientists but also of the multi-level nature of science itself. Here I want to say something (a) about what science is; (b) about why multi-level thinking—and taking more than one viewpoint—is so important for scientific as well as for other forms of understanding; and (c) about what is meant, at a deep level, by "scientific understanding" and trying to communicate it, not only with lay persons but also across professional disciplines. I hope that Professor YE would approve.

Space Vector Pulse Width Modulation of a Multi-Level Diode ...

African Journals Online (AJOL)

Space Vector Pulse Width Modulation of a Multi-Level Diode Clamped ... of MATLAB /SIMULINK modeling of the space vector pulse-width modulation and the ... two adjacent active vectors in determining the switching process of the multilevel ...

Clarifying the use of aggregated exposures in multilevel models: self-included vs. self-excluded measures.

Directory of Open Access Journals (Sweden)

Etsuji Suzuki

Full Text Available Multilevel analyses are ideally suited to assess the effects of ecological (higher level and individual (lower level exposure variables simultaneously. In applying such analyses to measures of ecologies in epidemiological studies, individual variables are usually aggregated into the higher level unit. Typically, the aggregated measure includes responses of every individual belonging to that group (i.e. it constitutes a self-included measure. More recently, researchers have developed an aggregate measure which excludes the response of the individual to whom the aggregate measure is linked (i.e. a self-excluded measure. In this study, we clarify the substantive and technical properties of these two measures when they are used as exposures in multilevel models.Although the differences between the two aggregated measures are mathematically subtle, distinguishing between them is important in terms of the specific scientific questions to be addressed. We then show how these measures can be used in two distinct types of multilevel models-self-included model and self-excluded model-and interpret the parameters in each model by imposing hypothetical interventions. The concept is tested on empirical data of workplace social capital and employees' systolic blood pressure.Researchers assume group-level interventions when using a self-included model, and individual-level interventions when using a self-excluded model. Analytical re-parameterizations of these two models highlight their differences in parameter interpretation. Cluster-mean centered self-included models enable researchers to decompose the collective effect into its within- and between-group components. The benefit of cluster-mean centering procedure is further discussed in terms of hypothetical interventions.When investigating the potential roles of aggregated variables, researchers should carefully explore which type of model-self-included or self-excluded-is suitable for a given situation

Doing Good Again? A Multilevel Institutional Perspective on Corporate Environmental Responsibility and Philanthropic Strategy

OpenAIRE

Liu, Wei; Wei, Qiao; Huang, Song-Qin; Tsai, Sang-Bing

2017-01-01

This study investigates the relationship between corporate environmental responsibility and corporate philanthropy. Using a sample of Chinese listed firms from 2008 to 2013, this paper examines the role of corporate environmental responsibility in corporate philanthropy and the moderating influence of the institutional environment using multilevel analysis. The results show that corporate eco-friendly events are positively associated with corporate philanthropic strategy to a significant degr...

Multilevel techniques for Reservoir Simulation

DEFF Research Database (Denmark)

Christensen, Max la Cour

The subject of this thesis is the development, application and study of novel multilevel methods for the acceleration and improvement of reservoir simulation techniques. The motivation for addressing this topic is a need for more accurate predictions of porous media flow and the ability to carry...... Full Approximation Scheme) • Variational (Galerkin) upscaling • Linear solvers and preconditioners First, a nonlinear multigrid scheme in the form of the Full Approximation Scheme (FAS) is implemented and studied for a 3D three-phase compressible rock/fluids immiscible reservoir simulator...... is extended to include a hybrid strategy, where FAS is combined with Newton’s method to construct a multilevel nonlinear preconditioner. This method demonstrates high efficiency and robustness. Second, an improved IMPES formulated reservoir simulator is implemented using a novel variational upscaling approach...

An Original Stepwise Multilevel Logistic Regression Analysis of Discriminatory Accuracy

DEFF Research Database (Denmark)

Merlo, Juan; Wagner, Philippe; Ghith, Nermin

2016-01-01

BACKGROUND AND AIM: Many multilevel logistic regression analyses of "neighbourhood and health" focus on interpreting measures of associations (e.g., odds ratio, OR). In contrast, multilevel analysis of variance is rarely considered. We propose an original stepwise analytical approach that disting...

The Universal Patient Centredness Questionnaire: scaling approaches to reduce positive skew

Directory of Open Access Journals (Sweden)

Bjertnaes O

2016-11-01

Full Text Available Oyvind Bjertnaes, Hilde Hestad Iversen, Andrew M Garratt Unit for Patient-Reported Quality, Norwegian Institute of Public Health, Oslo, Norway Purpose: Surveys of patients’ experiences typically show results that are indicative of positive experiences. Unbalanced response scales have reduced positive skew for responses to items within the Universal Patient Centeredness Questionnaire (UPC-Q. The objective of this study was to compare the unbalanced response scale with another unbalanced approach to scaling to assess whether the positive skew might be further reduced. Patients and methods: The UPC-Q was included in a patient experience survey conducted at the ward level at six hospitals in Norway in 2015. The postal survey included two reminders to nonrespondents. For patients in the first month of inclusion, UPC-Q items had standard scaling: poor, fairly good, good, very good, and excellent. For patients in the second month, the scaling was more positive: poor, good, very good, exceptionally good, and excellent. The effect of scaling on UPC-Q scores was tested with independent samples t-tests and multilevel linear regression analysis, the latter controlling for the hierarchical structure of data and known predictors of patient-reported experiences. Results: The response rate was 54.6% (n=4,970. Significantly lower scores were found for all items of the more positively worded scale: UPC-Q total score difference was 7.9 (P<0.001, on a scale from 0 to 100 where 100 is the best possible score. Differences between the four items of the UPC-Q ranged from 7.1 (P<0.001 to 10.4 (P<0.001. Multivariate multilevel regression analysis confirmed the difference between the response groups, after controlling for other background variables; UPC-Q total score difference estimate was 8.3 (P<0.001. Conclusion: The more positively worded scaling significantly lowered the mean scores, potentially increasing the sensitivity of the UPC-Q to identify differences over

The impact of individual and organisational factors on engagement of individuals with intellectual disability living in community group homes: a multilevel model.

Science.gov (United States)

Qian, X; Tichá, R; Larson, S A; Stancliffe, R J; Wuorio, A

2015-06-01

Being engaged in daily activities is a strong indicator of quality of life for individuals with intellectual disability (ID) who live in small community group homes. This study aimed to identify individual and organisational factors that predict high levels of engagement. Individuals with ID (n = 78), direct support professionals (DSPs; n = 174) and supervisors (n = 21) from 21 US group homes participated in the study. For each individual with ID, we conducted 80 min of observation at the person's residence. Information was also gathered regarding demographic characteristics, DSP competence, supervisor years of experience and management practices. Data were analysed using multilevel modelling. On average, individuals were engaged in social activities 12% of observed time and non-social activities 35% of the time. Individuals with greater adaptive skills who were supported by more competent staff showed significantly higher levels of social engagement. Individuals with less severe deficits in adaptive behaviours and less challenging behaviour showed higher levels of non-social engagement. Although none of the factors related to group homes were significant, 24% of the variance in non-social engagement existed among group homes. These results suggested that engagement is a dynamic construct. The extent to which an individual with ID is engaged in daily life is a result of interplay between the individual's characteristics and the group home environment. Future research is needed to investigate the influence of variables specific to the group home on the engagement level of individuals with disabilities. © 2014 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

Relationships between racial-ethnic identity, self-esteem and in-group attitudes among First Nation children.

Science.gov (United States)

Corenblum, Barry

2014-03-01

Positive in-group distinctiveness has been associated with self-esteem increases among adolescents and adults. To examine whether in-group biases are associated with self-esteem enhancement among minority group children, Native Canadian children (N = 414, 209 female) age 6-11 completed each year for 5 years, measures assessing their level of concrete operational thought, racial-ethnic identity, racial-ethnic centrality, implicit and explicit self-esteem, and implicit and explicit in-group attitudes. According to cognitive developmental theory, increases in the level of concrete operational thought will predict increases in racial-ethnic identity, and increases in identity should, in turn, predict more favorable in-group attitudes. Social identity theory predicts that more favorable in-group attitudes should predict increases in self-esteem. Multi-level structural equation modelling revealed support for these hypotheses. Cognitively mature children who identify closely with their group enhanced their level of self-esteem by positively differentiating between group members on dimensions that favor their group. Limitations of the present study and suggestions for future studies are also presented.

Theory of positive disintegration as a model of adolescent development.

Science.gov (United States)

Laycraft, Krystyna

2011-01-01

This article introduces a conceptual model of the adolescent development based on the theory of positive disintegration combined with theory of self-organization. Dabrowski's theory of positive disintegration, which was created almost a half century ago, still attracts psychologists' and educators' attention, and is extensively applied into studies of gifted and talented people. The positive disintegration is the mental development described by the process of transition from lower to higher levels of mental life and stimulated by tension, inner conflict, and anxiety. This process can be modeled by a sequence of patterns of organization (attractors) as a developmental potential (a control parameter) changes. Three levels of disintegration (unilevel disintegration, spontaneous multilevel disintegration, and organized multilevel disintegration) are analyzed in detail and it is proposed that they represent behaviour of early, middle and late periods of adolescence. In the discussion, recent research on the adolescent brain development is included.

A multilevel shape fit analysis of neutron transmission data

International Nuclear Information System (INIS)

Naguib, K.; Sallam, O.H.; Adib, M.

1989-01-01

A multilevel shape fit analysis of neutron transmission data is presented. A multilevel computer code SHAPE is used to analyse clean transmission data obtained from time-of-flight (TOF) measurements. The shape analysis deduces the parameters of the observed resonances in the energy region considered in the measurements. The shape code is based upon a least square fit of a multilevel Breit-Wigner formula and includes both instrumental resolution and Doppler broadenings. Operating the SHAPE code on a test example of a measured transmission data of 151 Eu, 153 Eu and natural Eu in the energy range 0.025-1 eV acquired a good result for the used technique of analysis. (author)

Detection of shielded radionuclides from weak and poorly resolved spectra using group positive RIVAL

International Nuclear Information System (INIS)

Kump, Paul; Bai, Er-Wei; Chan, Kung-Sik; Eichinger, William

2013-01-01

This paper is concerned with the identification of nuclides from weak and poorly resolved spectra in the presence of unknown radiation shielding materials such as carbon, water, concrete and lead. Since a shield will attenuate lower energies more so than higher ones, isotope sub-spectra must be introduced into models and into detection algorithms. We propose a new algorithm for detection, called group positive RIVAL, that encourages the selection of groups of sub-spectra rather than the selection of individual sub-spectra that may be from the same parent isotope. Indeed, the proposed algorithm incorporates group positive LASSO, and, as such, we supply the consistency results of group positive LASSO and adaptive group positive LASSO. In an example employing various shielding materials and material thicknesses, group positive RIVAL is shown to perform well in all scenarios with the exception of ones in which the shielding material is lead. - Highlights: ► Identification of nuclides from weak and poorly resolved spectra. ► Shielding materials such as carbon, water, concrete, and lead are considered. ► Isotope spectra are decomposed into their sub-spectra. ► A variable selection algorithm is proposed that encourages group selection. ► Simulations demonstrate the proposed method's performance when nuclides have been shielded

Design and Implementation of 13 Levels Multilevel Inverter for Photovoltaic System

Science.gov (United States)

Subramani, C.; Dhineshkumar, K.; Palanivel, P.

2018-04-01

This paper approaches the appearing and modernization of S-Type PV based 13- level multilevel inverter with less quantity of switch. The current S-Type Multi level inverter contains more number of switches and voltage sources. Multilevel level inverter is a be understandable among the most gainful power converters for high power application and present day applications with reduced switches. The fundamental good arrangement of the 13-level multilevel inverter is to get ventured voltage from a couple of levels of DC voltages.. The controller gives actual way day and age to switches through driver circuit using PWM methodology. The execution assessment of proposed multilevel inverter is checked using MATLAB/Simulink. This is the outstanding among other techniquem appeared differently in relation to all other existing system

Multilevel microvibration test for performance predictions of a space optical load platform

Science.gov (United States)

Li, Shiqi; Zhang, Heng; Liu, Shiping; Wang, Yue

2018-05-01

This paper presents a framework for the multilevel microvibration analysis and test of a space optical load platform. The test framework is conducted on three levels, including instrument, subsystem, and system level. Disturbance source experimental investigations are performed to evaluate the vibration amplitude and study vibration mechanism. Transfer characteristics of space camera are validated by a subsystem test, which allows the calculation of transfer functions from various disturbance sources to optical performance outputs. In order to identify the influence of the source on the spacecraft performance, a system level microvibration measurement test has been performed on the ground. From the time domain analysis and spectrum analysis of multilevel microvibration tests, we concluded that the disturbance source has a significant effect on its installation position. After transmitted through mechanical links, the residual vibration reduces to a background noise level. In addition, the angular microvibration of the platform jitter is mainly concentrated in the rotation of y-axes. This work is applied to a real practical application involving the high resolution satellite camera system.

Fast Multilevel Panel Method for Wind Turbine Rotor Flow Simulations

NARCIS (Netherlands)

van Garrel, Arne; Venner, Cornelis H.; Hoeijmakers, Hendrik Willem Marie

2017-01-01

A fast multilevel integral transform method has been developed that enables the rapid analysis of unsteady inviscid flows around wind turbines rotors. A low order panel method is used and the new multi-level multi-integration cluster (MLMIC) method reduces the computational complexity for

Model Predictive Control of Grid Connected Modular Multilevel Converter for Integration of Photovoltaic Power Systems

DEFF Research Database (Denmark)

Hajizadeh, Amin; Shahirinia, Amir

2017-01-01

Investigation of an advanced control structure for integration of Photovoltaic Power Systems through Grid Connected-Modular Multilevel Converter (GC-MMC) is proposed in this paper. To achieve this goal, a non-linear model of MMC regarding considering of negative and positive sequence components has...... been presented. Then, due to existence of unbalance voltage faults in distribution grid, non-linarites and uncertainties in model, model predictive controller which is developed for GC-MMC. They are implemented based upon positive and negative components of voltage and current to mitigate the power...

Stability of Boolean multilevel networks.

Science.gov (United States)

Cozzo, Emanuele; Arenas, Alex; Moreno, Yamir

2012-09-01

The study of the interplay between the structure and dynamics of complex multilevel systems is a pressing challenge nowadays. In this paper, we use a semiannealed approximation to study the stability properties of random Boolean networks in multiplex (multilayered) graphs. Our main finding is that the multilevel structure provides a mechanism for the stabilization of the dynamics of the whole system even when individual layers work on the chaotic regime, therefore identifying new ways of feedback between the structure and the dynamics of these systems. Our results point out the need for a conceptual transition from the physics of single-layered networks to the physics of multiplex networks. Finally, the fact that the coupling modifies the phase diagram and the critical conditions of the isolated layers suggests that interdependency can be used as a control mechanism.

Institutional Disparities in the Cost Effectiveness of GCE A-Level Provision: A Multi-Level Approach.

Science.gov (United States)

Fielding, A.

1995-01-01

Reanalyzes H. Thomas's 1980s data, which used teaching group as the unit of analysis and illuminated some institutional disparities in provision of General Certificate of Education (GCE) A-levels. Uses multilevel analysis to focus on individual students in a hierarchical framework. Among the study institutions, school sixth forms appear less…

FBILI method for multi-level line transfer

Science.gov (United States)

Kuzmanovska, O.; Atanacković, O.; Faurobert, M.

2017-07-01

Efficient non-LTE multilevel radiative transfer calculations are needed for a proper interpretation of astrophysical spectra. In particular, realistic simulations of time-dependent processes or multi-dimensional phenomena require that the iterative method used to solve such non-linear and non-local problem is as fast as possible. There are several multilevel codes based on efficient iterative schemes that provide a very high convergence rate, especially when combined with mathematical acceleration techniques. The Forth-and-Back Implicit Lambda Iteration (FBILI) developed by Atanacković-Vukmanović et al. [1] is a Gauss-Seidel-type iterative scheme that is characterized by a very high convergence rate without the need of complementing it with additional acceleration techniques. In this paper we make the implementation of the FBILI method to the multilevel atom line transfer in 1D more explicit. We also consider some of its variants and investigate their convergence properties by solving the benchmark problem of CaII line formation in the solar atmosphere. Finally, we compare our solutions with results obtained with the well known code MULTI.

Multi-Level Wavelet Shannon Entropy-Based Method for Single-Sensor Fault Location

Directory of Open Access Journals (Sweden)

Qiaoning Yang

2015-10-01

Full Text Available In actual application, sensors are prone to failure because of harsh environments, battery drain, and sensor aging. Sensor fault location is an important step for follow-up sensor fault detection. In this paper, two new multi-level wavelet Shannon entropies (multi-level wavelet time Shannon entropy and multi-level wavelet time-energy Shannon entropy are defined. They take full advantage of sensor fault frequency distribution and energy distribution across multi-subband in wavelet domain. Based on the multi-level wavelet Shannon entropy, a method is proposed for single sensor fault location. The method firstly uses a criterion of maximum energy-to-Shannon entropy ratio to select the appropriate wavelet base for signal analysis. Then multi-level wavelet time Shannon entropy and multi-level wavelet time-energy Shannon entropy are used to locate the fault. The method is validated using practical chemical gas concentration data from a gas sensor array. Compared with wavelet time Shannon entropy and wavelet energy Shannon entropy, the experimental results demonstrate that the proposed method can achieve accurate location of a single sensor fault and has good anti-noise ability. The proposed method is feasible and effective for single-sensor fault location.

Multilevel and multi-user sustainability assessment of farming systems

Energy Technology Data Exchange (ETDEWEB)

Van Passel, Steven, E-mail: Steven.vanpassel@uhasselt.be [Hasselt University, Faculty of Business Economics, Centre for Environmental Sciences, Agoralaan, Building D, 3590, Diepenbeek (Belgium); University of Antwerp, Department Bioscience Engineering, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Meul, Marijke [University College Ghent, Department of Biosciences and Landscape Architecture, Campus Schoonmeersen, Building C, Schoonmeersstraat 52, 9000, Gent (Belgium)

2012-01-15

Sustainability assessment is needed to build sustainable farming systems. A broad range of sustainability concepts, methodologies and applications already exists. They differ in level, focus, orientation, measurement, scale, presentation and intended end-users. In this paper we illustrate that a smart combination of existing methods with different levels of application can make sustainability assessment more profound, and that it can broaden the insights of different end-user groups. An overview of sustainability assessment tools on different levels and for different end-users shows the complementarities and the opportunities of using different methods. In a case-study, a combination of the sustainable value approach (SVA) and MOTIFS is used to perform a sustainability evaluation of farming systems in Flanders. SVA is used to evaluate sustainability at sector level, and is especially useful to support policy makers, while MOTIFS is used to support and guide farmers towards sustainability at farm level. The combined use of the two methods with complementary goals can widen the insights of both farmers and policy makers, without losing the particularities of the different approaches. To stimulate and support further research and applications, we propose guidelines for multilevel and multi-user sustainability assessments. - Highlights: Black-Right-Pointing-Pointer We give an overview of sustainability assessment tools for agricultural systems. Black-Right-Pointing-Pointer SVA and MOTIFS are used to evaluate the sustainability of dairy farming in Flanders. Black-Right-Pointing-Pointer Combination of methods with different levels broadens the insights of different end-user groups. Black-Right-Pointing-Pointer We propose guidelines for multilevel and multi-user sustainability assessments.

Multilevel and multi-user sustainability assessment of farming systems

International Nuclear Information System (INIS)

Van Passel, Steven; Meul, Marijke

2012-01-01

Sustainability assessment is needed to build sustainable farming systems. A broad range of sustainability concepts, methodologies and applications already exists. They differ in level, focus, orientation, measurement, scale, presentation and intended end-users. In this paper we illustrate that a smart combination of existing methods with different levels of application can make sustainability assessment more profound, and that it can broaden the insights of different end-user groups. An overview of sustainability assessment tools on different levels and for different end-users shows the complementarities and the opportunities of using different methods. In a case-study, a combination of the sustainable value approach (SVA) and MOTIFS is used to perform a sustainability evaluation of farming systems in Flanders. SVA is used to evaluate sustainability at sector level, and is especially useful to support policy makers, while MOTIFS is used to support and guide farmers towards sustainability at farm level. The combined use of the two methods with complementary goals can widen the insights of both farmers and policy makers, without losing the particularities of the different approaches. To stimulate and support further research and applications, we propose guidelines for multilevel and multi-user sustainability assessments. - Highlights: ► We give an overview of sustainability assessment tools for agricultural systems. ► SVA and MOTIFS are used to evaluate the sustainability of dairy farming in Flanders. ► Combination of methods with different levels broadens the insights of different end-user groups. ► We propose guidelines for multilevel and multi-user sustainability assessments.

Positioning in Groups: A New Development in Systemic Consultation

Science.gov (United States)

Matthews, Jeff W.; Singh, RajVinder

2015-01-01

This article describes a new approach, employing a combination of Positioning Theory and Semantic Polarities, that educational psychologists can use to develop and facilitate change in organisations and groups. Resistance to change can be seen as reflecting a lack of the language that the members of an organisation need to participate effectively…

Multi-level decision making models, methods and applications

CERN Document Server

Zhang, Guangquan; Gao, Ya

2015-01-01

This monograph presents new developments in multi-level decision-making theory, technique and method in both modeling and solution issues. It especially presents how a decision support system can support managers in reaching a solution to a multi-level decision problem in practice. This monograph combines decision theories, methods, algorithms and applications effectively. It discusses in detail the models and solution algorithms of each issue of bi-level and tri-level decision-making, such as multi-leaders, multi-followers, multi-objectives, rule-set-based, and fuzzy parameters. Potential readers include organizational managers and practicing professionals, who can use the methods and software provided to solve their real decision problems; PhD students and researchers in the areas of bi-level and multi-level decision-making and decision support systems; students at an advanced undergraduate, master’s level in information systems, business administration, or the application of computer science.  

New Switched-Dual-Source Multilevel Inverter for Symmetrical and Asymmetrical Operation

Directory of Open Access Journals (Sweden)

Kennedy Adinbo Aganah

2018-04-01

Full Text Available The increasing integration of large solar PV and wind farms into the power grid has fueled, over the past two decades, growing demands for high-power, high-voltage, utility-scale inverters. Multilevel inverters have emerged as the industry’s choice for megawatt-range inverters because of their reduced voltage stress, capability for generating an almost-sinusoidal voltage, built-in redundancy and other benefits. This paper presents a novel switched-source multilevel inverter (SS MLI architecture. This new inverter shows superior capabilities when compared to existing topologies. It has reduced voltage stress on the semiconductor, uses fewer switches (i.e., reduced size/weight/cost and exhibits increased efficiency. The proposed SS MLI is comprised of two voltage sources ( V 1 , V 2 and six switches. It is capable of generating five-level output voltage in symmetric mode (i.e., V 1 = V 2 and seven-level output voltage in asymmetric mode (i.e., V 1 ≠ V 2 . We present simulations results (using MATLAB®/Simulink® for five- and seven-level output voltages, and they strongly support the validity of the proposed inverter. These positive results are further supported experimentally using a laboratory prototype.

Thermo-mechanical analysis for multi-level HLW repository concept

International Nuclear Information System (INIS)

Kwon, Sang Ki; Choi, Jong Won

2004-01-01

This work aims to investigate the influence of design parameters for the underground high-level nuclear waste repository with multi-level concept. B. Necessity o In order to construct an HLW repository in deep underground, it is required to select a site, which is far from major discontinuities. To dispose the whole spent fuels generated from the Korean nuclear power plants in a repository, the underground area of about 4km 2 is required. This would be a constraints for selecting an adequate repository site. It is recommended to dispose the two different spent fuels, PWR and CANDU, in different areas at the operation efficiency point of view. It is necessary to investigate the influence of parameters, which can affect the stability of multi-level repository. It is also needed to consider the influence of heat generated from the HLW and the high in situ stress in deep location. Therefore, thermo-mechanical coupling analysis should be carried out and the results should be compared with the results from single-level repository concept. Three-dimensional analysis is required to model the disposal tunnel and deposition hole. It is recommended to use the Korean geological condition and actually measured rock properties in Korea in order to achieve reliable modeling results. A FISH routine developed for effective modeling of Thermal-Mechanical coupling was implemented in the modeling using FLAC3D, which is a commercial three-dimensional FDM code. The thermal and mechanical properties of rock and rock mass achieved from Yusung drilling site, were used for the computer modeling. Different parameters such as level distance, waste type disposed on different levels, and time interval between the operation on different levels, were considered in the three-dimensional analysis. From the analysis, it was possible to derive adequate multi-level repository concept. Results and recommendations for application From the thermal-mechanical analysis for the multi-level repository

Handbook of multilevel analysis

National Research Council Canada - National Science Library

Leeuw, Jan de; Meijer, Erik

2008-01-01

... appropriate and efficient model-based methods have become available to deal with this issue, that we have come to appreciate the power that more complex models provide for describing the world and providing new insights. This book sets out to present some of the most recent developments in what has come to be known as multilevel modelling. An...

Three-phase multilevel inverter configuration for open-winding high power application

DEFF Research Database (Denmark)

Sanjeevikumar, Padmanaban; Blaabjerg, Frede; Wheeler, Patrick William

2015-01-01

This paper work exploits a new dual open-winding three-phase multilevel inverter configuration suitable for high power medium-voltage applications. Modular structure comprised of standard three-phase voltage source inverter (VSI) along with one additional bi-directional semiconductor device (MOSFET...... for implementation purpose. Proposed dual-inverter configuration generates multilevel outputs with benefit includes reduced THD and dv/dt in comparison to other dual-inverter topologies. Complete model of the multilevel ac drive is developed with simple MSCFM modulation in Matlab/PLECs numerical software...

Multi-level nonlinear diffusion acceleration method for multigroup transport k-Eigenvalue problems

International Nuclear Information System (INIS)

Anistratov, Dmitriy Y.

2011-01-01

The nonlinear diffusion acceleration (NDA) method is an efficient and flexible transport iterative scheme for solving reactor-physics problems. This paper presents a fast iterative algorithm for solving multigroup neutron transport eigenvalue problems in 1D slab geometry. The proposed method is defined by a multi-level system of equations that includes multigroup and effective one-group low-order NDA equations. The Eigenvalue is evaluated in the exact projected solution space of smallest dimensionality, namely, by solving the effective one- group eigenvalue transport problem. Numerical results that illustrate performance of the new algorithm are demonstrated. (author)

Variable-speed wind power system with improved energy capture via multilevel conversion

Science.gov (United States)

Erickson, Robert W.; Al-Naseem, Osama A.; Fingersh, Lee Jay

2005-05-31

A system and method for efficiently capturing electrical energy from a variable-speed generator are disclosed. The system includes a matrix converter using full-bridge, multilevel switch cells, in which semiconductor devices are clamped to a known constant DC voltage of a capacitor. The multilevel matrix converter is capable of generating multilevel voltage wave waveform of arbitrary magnitude and frequencies. The matrix converter can be controlled by using space vector modulation.

The physical environment of positive places: Exploring differences between age groups.

Science.gov (United States)

Laatikainen, Tiina E; Broberg, Anna; Kyttä, Marketta

2017-02-01

Features of the physical environment have an impact on the human behaviour. Thus, planners and policymakers around the world should aim at providing environments that are perceived as being of good quality, in which the residents enjoy spending time and moving around in. It is widely acknowledged that urban environmental quality associates with well-being, but there is currently very little research examining which features of urban environments people of different ages perceive as appealing in their living environments. Individuals experience different age-related developmental environments throughout their life course. Thus, the usage and perceptions of different spaces can also differ between various age groups. Public Participation GIS datasets collected in 2009 and 2011 in Helsinki Metropolitan Area were used to study places perceived as being positive by adults (n=3119) and children (n=672). Participants marked points on a map that were overlaid with GIS data to study whether the physical environment of positive places of different age groups differed. The results demonstrated that the physical environment differs significantly in the positive places of different age groups. The places of adult age groups were characterized by green, blue and commercial spaces, whereas sports, residential and commercial spaces characterize children's and adolescents' places. Older adults' places were found to be closest to home, while adolescents' places were the most distant. Providing appealing environments for all age groups in one setting remains problematic but should nevertheless be strived for, especially in the urban context where a constant competition over different usages of space occurs. Copyright © 2016 Elsevier Inc. All rights reserved.

A Multilevel Secure Workflow Management System

National Research Council Canada - National Science Library

Kang, Myong H; Froscher, Judith N; Sheth, Amit P; Kochut, Krys J; Miller, John A

1999-01-01

The Department of Defense (DoD) needs multilevel secure (MLS) workflow management systems to enable globally distributed users and applications to cooperate across classification levels to achieve mission critical goals...

Anterior fusion technique for multilevel cervical spondylotic myelopathy: a retrospective analysis of surgical outcome of patients with different number of levels fused.

Directory of Open Access Journals (Sweden)

Shunzhi Yu

Full Text Available OBJECTIVE: The anterior approach for multilevel CSM has been developed and obtained favorable outcomes. However, the operation difficulty, invasiveness and operative risks increase when multi-level involved. This study was to assess surgical parameters, complications, clinical and radiological outcomes in the treatment of 2-, 3- and 4-level CSM. METHODS: A total of 248 patients with 2-, 3- or 4-level CSM who underwent anterior decompression and fusion procedures between October 2005 and June 2011 were divided into three groups, the 2-level group (106 patients, the 3-level group (98 patients and the 4-level group (44 patients. The clinical and Radiographic outcomes including Japanese Orthopedic Association (JOA score, Neck Disability Index (NDI score, Odom's Scale, hospital stay, blood loss, operation time, fusion rate, cervical lordosis, cervical range of motion (ROM, and complications were compared. RESULTS: At a minimum of 2-year follow-up, no statistical differences in JOA score, NDI score, Odom's Scale, hospital stay, fusion rate and cervical lordosis were found among the 3 groups. However, the mean postoperative NDI score of the 4-level group was significantly higher than that in the other two groups (P<0.05, and in terms of postoperative total ROM, the 3-level group was superior to the 4-level group and inferior to 2-level group (P<0.05. The decrease rate of ROM in the 3-level group was significantly higher than that in the 2-level group, and lower than that in the 4-level group (P<0.05. CONCLUSIONS: As the number of involved levels increased, surgical results become worse in terms of operative time, blood loss, NDI score, cervical ROM and complication rates postoperatively. An appropriate surgical procedure for multilevel CSM should be chosen according to comprehensive clinical evaluation before operation, thus reducing fusion and decompression levels if possible.

Group B Streptococcus Positive Culture’s Results in Pregnants with Preterm Premature Rupture of Membranes

Directory of Open Access Journals (Sweden)

Farzaneh Broomand

2008-09-01

Full Text Available Objective: Preterm premature rupture of membranes (PPROM occurs in 2% of all pregnancies. The aim of this study was to compare positive cultures of GBS in two groups of pregnant women.Materials and methods: This case control research was conducted on 242 pregnant women: first group was consisted of 117 pregnant with PPROM and gestational ages between 26-37 weeks; second group was consisted of 125 term pregnant women with intact membranes and before onset of labor. Rectovaginal and urine samples were studied using specific culture medium of GBS, "Todd Hewitt Broth". The percentage of positive results was calculated using odds ratio and chi-square test.Results: GBS cultures were positive in 20 cases (17% in PPROM group and 5 cases in group of term pregnant (4% (Odds ratio=4.95 CI= 1.79-13.67, p=0.001. Past history of preterm labor and neonate hospitalization were more common in PPROM group but without any significant relationship to positive cultures.Conclusion: Our study showed significant difference of GBS colonization rate between two groups (p=0.001. According to CDC and ACOG guidelines routine screening and treatment of positive cases are indicated.

Analysis of Harmonic Injection to the Modulation of Multi-Level ...

African Journals Online (AJOL)

This paper explores the analysis of third and ninth harmonic injection to the modulation of a multilevel diode clamped converter (DCC) at a varying modulation index. The spectral distributions of the various multi-level waveforms obtained under normal modulation index of 0.8 and over modulation index of 1.15 were ...

Analyzing chromatographic data using multilevel modeling.

Science.gov (United States)

Wiczling, Paweł

2018-06-01

It is relatively easy to collect chromatographic measurements for a large number of analytes, especially with gradient chromatographic methods coupled with mass spectrometry detection. Such data often have a hierarchical or clustered structure. For example, analytes with similar hydrophobicity and dissociation constant tend to be more alike in their retention than a randomly chosen set of analytes. Multilevel models recognize the existence of such data structures by assigning a model for each parameter, with its parameters also estimated from data. In this work, a multilevel model is proposed to describe retention time data obtained from a series of wide linear organic modifier gradients of different gradient duration and different mobile phase pH for a large set of acids and bases. The multilevel model consists of (1) the same deterministic equation describing the relationship between retention time and analyte-specific and instrument-specific parameters, (2) covariance relationships relating various physicochemical properties of the analyte to chromatographically specific parameters through quantitative structure-retention relationship based equations, and (3) stochastic components of intra-analyte and interanalyte variability. The model was implemented in Stan, which provides full Bayesian inference for continuous-variable models through Markov chain Monte Carlo methods. Graphical abstract Relationships between log k and MeOH content for acidic, basic, and neutral compounds with different log P. CI credible interval, PSA polar surface area.

Technology of forming a positive attitude to physical training students of special medical group

Directory of Open Access Journals (Sweden)

Mukhamediarov N.N.

2013-04-01

Full Text Available Defined effective technology stages of forming a positive attitude towards physical education of students in special medical groups, stimulate motivation, epistemologically, informative, content-procedural, analytical and adjustment. For each stage technology offered special tools: lectures, seminars, analysis articles, mini conference on improving technique, racing games, mini-competitions, diagnostic interviews, questionnaires, analysis of log data on attendance. Selected criteria forming positive attitudes towards physical education: theoretical and practical, formed groups for research: experimental and control, analyzed results introduction of technology, efficiency of the proposed technology and means forming a positive attitude towards physical education students in special medical groups.

Application of Multilevel Models to Morphometric Data. Part 2. Correlations

Directory of Open Access Journals (Sweden)

O. Tsybrovskyy

2003-01-01

Full Text Available Multilevel organization of morphometric data (cells are “nested” within patients requires special methods for studying correlations between karyometric features. The most distinct feature of these methods is that separate correlation (covariance matrices are produced for every level in the hierarchy. In karyometric research, the cell‐level (i.e., within‐tumor correlations seem to be of major interest. Beside their biological importance, these correlation coefficients (CC are compulsory when dimensionality reduction is required. Using MLwiN, a dedicated program for multilevel modeling, we show how to use multivariate multilevel models (MMM to obtain and interpret CC in each of the levels. A comparison with two usual, “single‐level” statistics shows that MMM represent the only way to obtain correct cell‐level correlation coefficients. The summary statistics method (take average values across each patient produces patient‐level CC only, and the “pooling” method (merge all cells together and ignore patients as units of analysis yields incorrect CC at all. We conclude that multilevel modeling is an indispensable tool for studying correlations between morphometric variables.

Multi-level analysis in information systems research: the case of enterprise resource planning system usage in China

Science.gov (United States)

Sun, Yuan; Bhattacherjee, Anol

2011-11-01

Information technology (IT) usage within organisations is a multi-level phenomenon that is influenced by individual-level and organisational-level variables. Yet, current theories, such as the unified theory of acceptance and use of technology, describe IT usage as solely an individual-level phenomenon. This article postulates a model of organisational IT usage that integrates salient organisational-level variables such as user training, top management support and technical support within an individual-level model to postulate a multi-level model of IT usage. The multi-level model was then empirically validated using multi-level data collected from 128 end users and 26 managers in 26 firms in China regarding their use of enterprise resource planning systems and analysed using the multi-level structural equation modelling (MSEM) technique. We demonstrate the utility of MSEM analysis of multi-level data relative to the more common structural equation modelling analysis of single-level data and show how single-level data can be aggregated to approximate multi-level analysis when multi-level data collection is not possible. We hope that this article will motivate future scholars to employ multi-level data and multi-level analysis for understanding organisational phenomena that are truly multi-level in nature.

Stakeholder conceptualisation of multi-level HIV and AIDS determinants in a Black epicentre.

Science.gov (United States)

Brawner, Bridgette M; Reason, Janaiya L; Hanlon, Kelsey; Guthrie, Barbara; Schensul, Jean J

2017-09-01

HIV has reached epidemic proportions among African Americans in the USA but certain urban contexts appear to experience a disproportionate disease burden. Geographic information systems mapping in Philadelphia indicates increased HIV incidence and prevalence in predominantly Black census tracts, with major differences across adjacent communities. What factors shape these geographic HIV disparities among Black Philadelphians? This descriptive study was designed to refine and validate a conceptual model developed to better understand multi-level determinants of HIV-related risk among Black Philadelphians. We used an expanded ecological approach to elicit reflective perceptions from administrators, direct service providers and community members about individual, social and structural factors that interact to protect against or increase the risk for acquiring HIV within their community. Gender equity, social capital and positive cultural mores (e.g., monogamy, abstinence) were seen as the main protective factors. Historical negative contributory influences of racial residential segregation, poverty and incarceration were among the most salient risk factors. This study was a critical next step toward initiating theory-based, multi-level community-based HIV prevention initiatives.

Designing of vague logic based multilevel feedback queue scheduler

Directory of Open Access Journals (Sweden)

Supriya Raheja

2016-03-01

Full Text Available Multilevel feedback queue scheduler suffers from major issues of scheduling such as starvation for long tasks, fixed number of queues, and static length of time quantum in each queue. These factors directly affect the performance of the scheduler. At many times impreciseness exists in attributes of tasks which make the performance even worse. In this paper, our intent is to improve the performance by providing a solution to these issues. We design a multilevel feedback queue scheduler using a vague set which we call as VMLFQ scheduler. VMLFQ scheduler intelligently handles the impreciseness and defines the optimum number of queues as well as the optimal size of time quantum for each queue. It also resolves the problem of starvation. This paper simulates and analyzes the performance of VMLFQ scheduler with the other multilevel feedback queue techniques using MatLab.

Optimized Thermal Management System of Modular Multilevel Converter for HVDC applications

DEFF Research Database (Denmark)

Hajizadeh, Amin

2017-01-01

The dynamical behavior of temperature is becoming a critical design consideration for the Modular Multilevel Converter (MMC). Investigation of an advanced control structure for Grid Connected-Modular Multilevel Converter (GC-MMC) is proposed in this paper. To achieve this goal, an non-linear mode...

Social capital and dental pain in Brazilian northeast: a multilevel cross-sectional study

Directory of Open Access Journals (Sweden)

Santiago Bianca Marques

2013-01-01

Full Text Available Abstract Background There is limited evidence on possible associations between social determinants and dental pain. This study investigated the relationship of neighborhood and individual social capital with dental pain in adolescents, adults and the elderly. Methods A population-based multilevel study was conducted involving 624 subjects from 3 age groups: 15–19, 35–44 and 65–74 years. They were randomly selected from 30 census tracts in three cities in the State of Paraíba, Brazil. A two-stage cluster sampling was used considering census tracts and households as sampling units. The outcome of study was the presence of dental pain in the last 6 months. Information on dental pain, demographic, socio-economic, health-related behaviors, use of dental services, self-perceived oral health and social capital measures was collected through interviews. Participants underwent a clinical examination for assessment of dental caries. Neighborhood social capital was evaluated using aggregated measures of social trust, social control, empowerment, political efficacy and neighborhood safety. Individual social capital assessment included bonding and bridging social capital. Multilevel logistic regression was used to test the relationship of neighborhood and individual social capital with dental pain after sequential adjustment for covariates. Results Individuals living in neighborhoods with high social capital were 52% less likely to report dental pain than those living in neighborhoods with low social capital (OR = 0.48, 95% CI = 0.27-0.85. Bonding social capital (positive interaction was independently associated with dental pain (OR = 0.88, 95% CI = 0.80-0.91. Last dental visit, self-perceived oral health and number of decayed teeth were also significantly associated with dental pain. Conclusions Our findings suggest that contextual and individual social capital are independently associated with dental pain.

The Sage handbook of multilevel modeling

CERN Document Server

Scott, Marc A; Marx, Brian D

2013-01-01

Leading contributors combine practical pieces with overviews of the state of the art in the field, making this handbook essential reading for any student or researcher looking to apply multilevel techniques in their own research

Optimal Multi-Level Lot Sizing for Requirements Planning Systems

OpenAIRE

Earle Steinberg; H. Albert Napier

1980-01-01

The wide spread use of advanced information systems such as Material Requirements Planning (MRP) has significantly altered the practice of dependent demand inventory management. Recent research has focused on development of multi-level lot sizing heuristics for such systems. In this paper, we develop an optimal procedure for the multi-period, multi-product, multi-level lot sizing problem by modeling the system as a constrained generalized network with fixed charge arcs and side constraints. T...

Modeling Learning in Doubly Multilevel Binary Longitudinal Data Using Generalized Linear Mixed Models: An Application to Measuring and Explaining Word Learning.

Science.gov (United States)

Cho, Sun-Joo; Goodwin, Amanda P

2016-04-01

When word learning is supported by instruction in experimental studies for adolescents, word knowledge outcomes tend to be collected from complex data structure, such as multiple aspects of word knowledge, multilevel reader data, multilevel item data, longitudinal design, and multiple groups. This study illustrates how generalized linear mixed models can be used to measure and explain word learning for data having such complexity. Results from this application provide deeper understanding of word knowledge than could be attained from simpler models and show that word knowledge is multidimensional and depends on word characteristics and instructional contexts.

A 2 × 2 taxonomy of multilevel latent contextual models: accuracy-bias trade-offs in full and partial error correction models.

Science.gov (United States)

Lüdtke, Oliver; Marsh, Herbert W; Robitzsch, Alexander; Trautwein, Ulrich

2011-12-01

In multilevel modeling, group-level variables (L2) for assessing contextual effects are frequently generated by aggregating variables from a lower level (L1). A major problem of contextual analyses in the social sciences is that there is no error-free measurement of constructs. In the present article, 2 types of error occurring in multilevel data when estimating contextual effects are distinguished: unreliability that is due to measurement error and unreliability that is due to sampling error. The fact that studies may or may not correct for these 2 types of error can be translated into a 2 × 2 taxonomy of multilevel latent contextual models comprising 4 approaches: an uncorrected approach, partial correction approaches correcting for either measurement or sampling error (but not both), and a full correction approach that adjusts for both sources of error. It is shown mathematically and with simulated data that the uncorrected and partial correction approaches can result in substantially biased estimates of contextual effects, depending on the number of L1 individuals per group, the number of groups, the intraclass correlation, the number of indicators, and the size of the factor loadings. However, the simulation study also shows that partial correction approaches can outperform full correction approaches when the data provide only limited information in terms of the L2 construct (i.e., small number of groups, low intraclass correlation). A real-data application from educational psychology is used to illustrate the different approaches.

Partnership for Healthier Asians: Disseminating Evidence-Based Practices in Asian-American Communities Using a Market-Oriented and Multilevel Approach

Science.gov (United States)

Kim, Karen; Quinn, Michael; Chandrasekar, Edwin; Patel, Reena

2016-01-01

Background One of the greatest challenges facing health promotion and disease prevention is translating research findings into evidence-based practices (EBP). There is currently a limited research base to inform the design of dissemination action plans, especially within medically underserved communities. Objective The objective of this paper is to describe an innovative study protocol to disseminate colorectal cancer (CRC) screening guidelines in seven Asian subgroups. Methods This study integrated a market-oriented Push-Pull-Infrastructure Model, Diffusion of Innovation Theory, and community-based participatory research approach to create a community-centered dissemination framework. Consumer research, through focus groups and community-wide surveys, was centered on the adopters to ensure a multilevel intervention was well designed and effective. Results Collaboration took place between an academic institution and eight community-based organizations. These groups worked together to conduct thorough consumer research. A sample of 72 Asian Americans participated in 8 focus groups, and differences were noted across ethnic groups. Furthermore, 464 community members participated in an Individual Client Survey. Most participants agreed that early detection of cancer was important (434/464, 93.5%), cancer could happen to anyone (403/464, 86.9%), CRC could be prevented (344/464, 74.1%), and everyone should screen for CRC (389/464, 83.8%). However, 35.8% (166/464) of participants also felt that people were better off not knowing it they had cancer, and 45.5% (211/464) would screen only when they had symptoms. Most participants indicated that they would screen upon their doctor’s recommendation, but half reported that they only saw a doctor when they were sick. Data collection currently is underway for a multilevel intervention (community health advisor and social marketing campaign) and will conclude March 2016. We expect that analysis and results will be available by

Partnership for Healthier Asians: Disseminating Evidence-Based Practices in Asian-American Communities Using a Market-Oriented and Multilevel Approach.

Science.gov (United States)

Kim, Karen; Quinn, Michael; Chandrasekar, Edwin; Patel, Reena; Lam, Helen

2016-06-16

One of the greatest challenges facing health promotion and disease prevention is translating research findings into evidence-based practices (EBP). There is currently a limited research base to inform the design of dissemination action plans, especially within medically underserved communities. The objective of this paper is to describe an innovative study protocol to disseminate colorectal cancer (CRC) screening guidelines in seven Asian subgroups. This study integrated a market-oriented Push-Pull-Infrastructure Model, Diffusion of Innovation Theory, and community-based participatory research approach to create a community-centered dissemination framework. Consumer research, through focus groups and community-wide surveys, was centered on the adopters to ensure a multilevel intervention was well designed and effective. Collaboration took place between an academic institution and eight community-based organizations. These groups worked together to conduct thorough consumer research. A sample of 72 Asian Americans participated in 8 focus groups, and differences were noted across ethnic groups. Furthermore, 464 community members participated in an Individual Client Survey. Most participants agreed that early detection of cancer was important (434/464, 93.5%), cancer could happen to anyone (403/464, 86.9%), CRC could be prevented (344/464, 74.1%), and everyone should screen for CRC (389/464, 83.8%). However, 35.8% (166/464) of participants also felt that people were better off not knowing it they had cancer, and 45.5% (211/464) would screen only when they had symptoms. Most participants indicated that they would screen upon their doctor's recommendation, but half reported that they only saw a doctor when they were sick. Data collection currently is underway for a multilevel intervention (community health advisor and social marketing campaign) and will conclude March 2016. We expect that analysis and results will be available by June 2016. This study outlines a

Multilevel Inverter by Cascading Industrial VSI

DEFF Research Database (Denmark)

Teodorescu, Remus; Blaabjerg, Frede; Pedersen, John Kim

2002-01-01

In this paper the modularity concept applied to medium-voltage adjustable speed drives is addressed. First, the single-phase cascaded voltage-source inverter that uses series connection of IGBT H-bridge modules with isolated dc-buses is presented. Next, a novel three-phase cascaded voltage......-source inverter that uses three IGBT triphase inverter modules along with an output transformer to obtain a 3 p.u. multilevel output voltage is introduced. The system yields in high-quality multistep voltage with up to 4 levels and low dv/dt, balanced operation of the inverter modules, each supplying a third...... of the motor rated kVA. The concept of using cascaded inverters is further extended to a new modular motor-modular inverter system where the motor winding connections are reconnected into several three-phase groups, either six-lead or 12-lead connection according to the voltage level, each powered...

Motivation and Self-Regulated Learning: A Multivariate Multilevel Analysis

Directory of Open Access Journals (Sweden)

Wondimu Ahmed

2017-09-01

Full Text Available This study investigated the relationship between motivation and self-regulated learning (SRL in a nationally representative sample of 5245, 15-year-old students in the USA. A multivariate multilevel analysis was conducted to examine the role of three motivational variables (self-efficacy, intrinsic value & instrumental value in predicting three SRL strategies (memorization, elaboration & control. The results showed that compared to self-efficacy, intrinsic value and instrumental value of math were stronger predictors of memorization, elaboration and control strategies. None of the motivational variables had a stronger effect on one strategy than the other. The findings suggest that the development of self-regulatory skills in math can be greatly enhanced by helping students develop positive value of and realistic expectancy for success in math.

Multi-level methods for solving multigroup transport eigenvalue problems in 1D slab geometry

International Nuclear Information System (INIS)

Anistratov, D. Y.; Gol'din, V. Y.

2009-01-01

A methodology for solving eigenvalue problems for the multigroup neutron transport equation in 1D slab geometry is presented. In this paper we formulate and compare different variants of nonlinear multi-level iteration methods. They are defined by means of multigroup and effective one-group low-order quasi diffusion (LOQD) equations. We analyze the effects of utilization of the effective one-group LOQD problem for estimating the eigenvalue. We present numerical results to demonstrate the performance of the iteration algorithms in different types of reactor-physics problems. (authors)

Utilities of gossip across organizational levels : Multilevel selection, free-riders, and teams.

Science.gov (United States)

Kniffin, Kevin M; Wilson, David Sloan

2005-09-01

Gossip is a subject that has been studied by researchers from an array of disciplines with various foci and methods. We measured the content of language use by members of a competitive sports team across 18 months, integrating qualitative ethnographic methods with quantitative sampling and analysis. We hypothesized that the use of gossip will vary significantly depending on whether it is used for self-serving or group-serving purposes. Our results support a model of gossip derived from multilevel selection theory that expects gossip to serve group-beneficial rules when rewards are partitioned at the group level on a scale that permits mutual monitoring. We integrate our case study with earlier studies of gossip conducted by anthropologists, psychologists, and management researchers.

COORDINATION IN MULTILEVEL NETWORK-CENTRIC CONTROL SYSTEMS OF REGIONAL SECURITY: APPROACH AND FORMAL MODEL

Directory of Open Access Journals (Sweden)

A. V. Masloboev

2015-01-01

Full Text Available The paper deals with development of methods and tools for mathematical and computer modeling of the multilevel network-centric control systems of regional security. This research is carried out under development strategy implementation of the Arctic zone of the Russian Federation and national safeguarding for the period before 2020 in the Murmansk region territory. Creation of unified interdepartmental multilevel computer-aided system is proposed intended for decision-making information support and socio-economic security monitoring of the Arctic regions of Russia. The distinctive features of the investigated system class are openness, self-organization, decentralization of management functions and decision-making, weak hierarchy in the decision-making circuit and goal generation capability inside itself. Research techniques include functional-target approach, mathematical apparatus of multilevel hierarchical system theory and principles of network-centric control of distributed systems with pro-active components and variable structure. The work considers network-centric management local decisions coordination problem-solving within the multilevel distributed systems intended for information support of regional security. The coordination problem-solving approach and problem formalization in the multilevel network-centric control systems of regional security have been proposed based on developed multilevel recurrent hierarchical model of regional socio-economic system complex security. The model provides coordination of regional security indexes, optimized by the different elements of multilevel control systems, subject to decentralized decision-making. The model specificity consists in application of functional-target technology and mathematical apparatus of multilevel hierarchical system theory for coordination procedures implementation of the network-centric management local decisions. The work-out and research results can find further

Is Preventative Long-Segment Surgery for Multi-Level Spondylolysis Necessary? A Finite Element Analysis Study.

Directory of Open Access Journals (Sweden)

Jianqiang Mo

Full Text Available For multi-level spondylolysis patients, surgeons commonly choose to fix all the segments with pars interarticularis defect even those without slippage and not responsible for clinical symptoms. In this study, we tried to study the necessity of the preventative long-segment surgery for the defected segment without slippage in treatment of multi-level spondylolysis patients from a biomechanical perspective.We established a bi-level spondylolysis model with pars defects at L4 and L5 segments, and simulated posterior lumbar interbody fusion (PLIF and pedicle screw fixation at L5-S1 level. Then we compared the biomechanical changes at L4 segment before and after surgery in neutral, flexion, extension, lateral bending and axial rotation position.The stress on L4 pars interarticularis was very similar before and after surgery, and reached the highest in axial rotation. The L3-L4 intradiscal pressure was almost the same, while L4-L5 intradiscal pressure changed a little in lateral bending (increase from 1.993 to 2.160 MPa and axial rotation (decrease from 1.639 to 1.307 MPa after surgery. The PLIF surgery caused a little increase of range of motion at adjacent L4-L5 and L3-L4 levels, but the change is very tiny (1 degree.The PLIF surgery will not cause significant biomechanical change at adjacent segment with pars defect in multi-level spondylolysis. On the contrary, excessive long-segment surgery will damage surrounding soft tissues which are important for maintaining the stability of spine. So a preventative long-segment surgery is not necessary for multi-level spondylolysis as long as there are no soft tissue degeneration signs at adjacent level.

Is Preventative Long-Segment Surgery for Multi-Level Spondylolysis Necessary? A Finite Element Analysis Study.

Science.gov (United States)

Mo, Jianqiang; Zhang, Wen; Zhong, Dongyan; Xu, Hao; Wang, Lan; Yu, Jia; Luo, Zongping

2016-01-01

For multi-level spondylolysis patients, surgeons commonly choose to fix all the segments with pars interarticularis defect even those without slippage and not responsible for clinical symptoms. In this study, we tried to study the necessity of the preventative long-segment surgery for the defected segment without slippage in treatment of multi-level spondylolysis patients from a biomechanical perspective. We established a bi-level spondylolysis model with pars defects at L4 and L5 segments, and simulated posterior lumbar interbody fusion (PLIF) and pedicle screw fixation at L5-S1 level. Then we compared the biomechanical changes at L4 segment before and after surgery in neutral, flexion, extension, lateral bending and axial rotation position. The stress on L4 pars interarticularis was very similar before and after surgery, and reached the highest in axial rotation. The L3-L4 intradiscal pressure was almost the same, while L4-L5 intradiscal pressure changed a little in lateral bending (increase from 1.993 to 2.160 MPa) and axial rotation (decrease from 1.639 to 1.307 MPa) after surgery. The PLIF surgery caused a little increase of range of motion at adjacent L4-L5 and L3-L4 levels, but the change is very tiny (1 degree). The PLIF surgery will not cause significant biomechanical change at adjacent segment with pars defect in multi-level spondylolysis. On the contrary, excessive long-segment surgery will damage surrounding soft tissues which are important for maintaining the stability of spine. So a preventative long-segment surgery is not necessary for multi-level spondylolysis as long as there are no soft tissue degeneration signs at adjacent level.

Analog Filter Design Rules for Multilevel Polybinary Signaling Generation

DEFF Research Database (Denmark)

Vegas Olmos, Juan José; Cavallero, Francisco javier Vaquero; Tafur Monroy, Idelfonso

2014-01-01

Polybinary signaling has gained attention lately due to its generation simplicity and reduced spectral usage. This paper presents a study on the requirements for analog filters for the generation of multilevel polybinary signals with three to nine levels.......Polybinary signaling has gained attention lately due to its generation simplicity and reduced spectral usage. This paper presents a study on the requirements for analog filters for the generation of multilevel polybinary signals with three to nine levels....

Domain decomposition and multilevel integration for fermions

International Nuclear Information System (INIS)

Ce, Marco; Giusti, Leonardo; Schaefer, Stefan

2016-01-01

The numerical computation of many hadronic correlation functions is exceedingly difficult due to the exponentially decreasing signal-to-noise ratio with the distance between source and sink. Multilevel integration methods, using independent updates of separate regions in space-time, are known to be able to solve such problems but have so far been available only for pure gauge theory. We present first steps into the direction of making such integration schemes amenable to theories with fermions, by factorizing a given observable via an approximated domain decomposition of the quark propagator. This allows for multilevel integration of the (large) factorized contribution to the observable, while its (small) correction can be computed in the standard way.

Liking is not the opposite of disliking: the functional separability of positive and negative attitudes toward minority groups.

Science.gov (United States)

Pittinsky, Todd L; Rosenthal, Seth A; Montoya, R Matthew

2011-04-01

Two studies tested the hypotheses that positive and negative attitudes toward minority groups are not interchangeable in predicting positive versus negative behaviors toward those groups. In Study 1, positive attitudes about Latinos were a better predictor of a positive behavior toward Latinos than were negative attitudes or stereotyped positive attitudes. In Study 2, positive attitudes about African Americans were a better predictor of positive behavioral intentions toward that group than were negative attitudes, whereas negative attitudes were better predictors of negative behavioral intentions than were positive attitudes. Taken together, the studies support the perspective that positive and negative attitudes toward minority groups are theoretically and functionally distinct constructs. We conclude that it is important to measure both positive and negative attitudes to understand and predict behaviors toward minority groups.

Contextual effect of positive intergroup contact on outgroup prejudice

Science.gov (United States)

Christ, Oliver; Schmid, Katharina; Lolliot, Simon; Swart, Hermann; Stolle, Dietlind; Tausch, Nicole; Al Ramiah, Ananthi; Wagner, Ulrich; Vertovec, Steven; Hewstone, Miles

2014-01-01

We assessed evidence for a contextual effect of positive intergroup contact, whereby the effect of intergroup contact between social contexts (the between-level effect) on outgroup prejudice is greater than the effect of individual-level contact within contexts (the within-level effect). Across seven large-scale surveys (five cross-sectional and two longitudinal), using multilevel analyses, we found a reliable contextual effect. This effect was found in multiple countries, operationalizing context at multiple levels (regions, districts, and neighborhoods), and with and without controlling for a range of demographic and context variables. In four studies (three cross-sectional and one longitudinal) we showed that the association between context-level contact and prejudice was largely mediated by more tolerant norms. In social contexts where positive contact with outgroups was more commonplace, norms supported such positive interactions between members of different groups. Thus, positive contact reduces prejudice on a macrolevel, whereby people are influenced by the behavior of others in their social context, not merely on a microscale, via individuals’ direct experience of positive contact with outgroup members. These findings reinforce the view that contact has a significant role to play in prejudice reduction, and has great policy potential as a means to improve intergroup relations, because it can simultaneously impact large numbers of people. PMID:24591627

Contextual effect of positive intergroup contact on outgroup prejudice.

Science.gov (United States)

Christ, Oliver; Schmid, Katharina; Lolliot, Simon; Swart, Hermann; Stolle, Dietlind; Tausch, Nicole; Al Ramiah, Ananthi; Wagner, Ulrich; Vertovec, Steven; Hewstone, Miles

2014-03-18

We assessed evidence for a contextual effect of positive intergroup contact, whereby the effect of intergroup contact between social contexts (the between-level effect) on outgroup prejudice is greater than the effect of individual-level contact within contexts (the within-level effect). Across seven large-scale surveys (five cross-sectional and two longitudinal), using multilevel analyses, we found a reliable contextual effect. This effect was found in multiple countries, operationalizing context at multiple levels (regions, districts, and neighborhoods), and with and without controlling for a range of demographic and context variables. In four studies (three cross-sectional and one longitudinal) we showed that the association between context-level contact and prejudice was largely mediated by more tolerant norms. In social contexts where positive contact with outgroups was more commonplace, norms supported such positive interactions between members of different groups. Thus, positive contact reduces prejudice on a macrolevel, whereby people are influenced by the behavior of others in their social context, not merely on a microscale, via individuals' direct experience of positive contact with outgroup members. These findings reinforce the view that contact has a significant role to play in prejudice reduction, and has great policy potential as a means to improve intergroup relations, because it can simultaneously impact large numbers of people.

Peer Group Socialization of Homophobic Attitudes and Behavior during Adolescence

Science.gov (United States)

Poteat, V. Paul

2007-01-01

A social developmental framework was applied to test for the socialization of homophobic attitudes and behavior within adolescent peer groups (Grades 7-11; aged 12-17 years). Substantial similarity within and differences across groups were documented. Multilevel models identified a group socializing contextual effect, predicting homophobic…

Agent-based model with multi-level herding for complex financial systems

Science.gov (United States)

Chen, Jun-Jie; Tan, Lei; Zheng, Bo

2015-02-01

In complex financial systems, the sector structure and volatility clustering are respectively important features of the spatial and temporal correlations. However, the microscopic generation mechanism of the sector structure is not yet understood. Especially, how to produce these two features in one model remains challenging. We introduce a novel interaction mechanism, i.e., the multi-level herding, in constructing an agent-based model to investigate the sector structure combined with volatility clustering. According to the previous market performance, agents trade in groups, and their herding behavior comprises the herding at stock, sector and market levels. Further, we propose methods to determine the key model parameters from historical market data, rather than from statistical fitting of the results. From the simulation, we obtain the sector structure and volatility clustering, as well as the eigenvalue distribution of the cross-correlation matrix, for the New York and Hong Kong stock exchanges. These properties are in agreement with the empirical ones. Our results quantitatively reveal that the multi-level herding is the microscopic generation mechanism of the sector structure, and provide new insight into the spatio-temporal interactions in financial systems at the microscopic level.

The effects of conflict asymmetry on work group and individual outcomes

NARCIS (Netherlands)

Jehn, K.A.; Rispens, S.; Thatcher, S.M.B.

2010-01-01

We examine the consequences of an often ignored aspect of work group conflict—asymmetric conflict perceptions—for the effectiveness of individuals and groups. Tests of our multilevel hypotheses using data on 51 work groups showed that group conflict asymmetry (the degree to which members differ in

Asynchronous monitoring of the quality of multilevel optical PAM signals

Science.gov (United States)

Siuzdak, J.

2017-08-01

In the paper, there is analyzed the signal quality assessment method based on delay tap asynchronous sampling, both for binary and multilevel PAM signals. The obtained multilevel phase diagrams are far more complicated than binary ones. The phase diagrams are affected by the signal distortions but it is difficult to relate reliably the phase diagram form to the distortion type and its influence on the signal quality.

Profiling of Junior College Football Players and Differences between Position Groups

Directory of Open Access Journals (Sweden)

Robert G. Lockie

2016-08-01

Full Text Available This study profiled junior college football players. Sixty-two subjects completed vertical jump (VJ; height and peak power, standing broad jump (SBJ, 36.58 m sprint, pro-agility shuttle, three-cone drill, and maximal-repetition bench press and front squat. The sample included 2 quarterbacks (QB, 7 running backs (RB, 13 wide receivers (WR, 1 tight end (TE, 18 defensive backs (DB, 8 linebackers (LB, and 13 offensive and defensive linemen (LM. To investigate positional differences, subjects were split into skill (SK; WR, DB, big skill (BSK; QB, RB, TE, LB, and LM groups. A one-way ANOVA determined between-group differences. LM were taller and heavier than SK and BSK players. The SK and BSK groups were faster than LM in the 0–36.58 m sprint, pro-agility shuttle, and three-cone drill (p ≤ 0.009. The SK group had greater VJ height and SBJ distance; LM generated greater VJ peak power (p ≤ 0.022. There were no between-group differences in the strength endurance tests. Compared to Division I data, junior college players were smaller, slower, and performed worse in jump tests. Positional differences in junior college football are typical to that of established research. Junior college players should attempt to increase body mass, and improve speed and lower-body power.

Simple Multi-level Microchannel Fabrication by Pseudo-Grayscale Backside Diffused Light Lithography.

Science.gov (United States)

Lai, David; Labuz, Joseph M; Kim, Jiwon; Luker, Gary D; Shikanov, Ariella; Takayama, Shuichi

2013-11-14

Photolithography of multi-level channel features in microfluidics is laborious and/or costly. Grayscale photolithography is mostly used with positive photoresists and conventional front side exposure, but the grayscale masks needed are generally costly and positive photoresists are not commonly used in microfluidic rapid prototyping. Here we introduce a simple and inexpensive alternative that uses pseudo-grayscale (pGS) photomasks in combination with backside diffused light lithography (BDLL) and the commonly used negative photoresist, SU-8. BDLL can produce smooth multi-level channels of gradually changing heights without use of true grayscale masks because of the use of diffused light. Since the exposure is done through a glass slide, the photoresist is cross-linked from the substrate side up enabling well-defined and stable structures to be fabricated from even unspun photoresist layers. In addition to providing unique structures and capabilities, the method is compatible with the "garage microfluidics" concept of creating useful tools at low cost since pGS BDLL can be performed with the use of only hot plates and a UV transilluminator: equipment commonly found in biology labs. Expensive spin coaters or collimated UV aligners are not needed. To demonstrate the applicability of pGS BDLL, a variety of weir-type cell traps were constructed with a single UV exposure to separate cancer cells (MDA-MB-231, 10-15 μm in size) from red blood cells (RBCs, 2-8 μm in size) as well as follicle clusters (40-50 μm in size) from cancer cells (MDA-MB-231, 10-15 μm in size).

DC-DC Type High-Frequency Link DC for Improved Power Quality of Cascaded Multilevel Inverter

Science.gov (United States)

Sadikin, Muhammad; Senjyu, Tomonobu; Yona, Atsushi

2013-06-01

Multilevel inverters are emerging as a new breed of power converter options for power system applications. Recent advances in power switching devices enabled the suitability of multilevel inverters for high voltage and high power applications because they are connecting several devices in series without the need of component matching. Usually, a transformerless battery energy storage system, based on a cascaded multilevel inverter, is used as a measure for voltage and frequency deviations. System can be reduced in size, weight, and cost of energy storage system. High-frequency link circuit topology is advantageous in realizing compact and light-weight power converters for uninterruptible power supply systems, new energy systems using photovoltaic-cells, fuel-cells and so on. This paper presents a DC-DC type high-frequency link DC (HFLDC) cascaded multilevel inverter. Each converter cell is implemented a control strategy for two H-bridge inverters that are controlled with the same multicarrier pulse width modulation (PWM) technique. The proposed cascaded multilevel inverter generates lower voltage total harmonic distortion (THD) in comparison with conventional cascaded multilevel inverter. Digital simulations are carried out using PSCAD/EMTDC to validate the performance of the proposed cascaded multilevel inverter.

Mathematical model comparing of the multi-level economics systems

Science.gov (United States)

Brykalov, S. M.; Kryanev, A. V.

2017-12-01

The mathematical model (scheme) of a multi-level comparison of the economic system, characterized by the system of indices, is worked out. In the mathematical model of the multi-level comparison of the economic systems, the indicators of peer review and forecasting of the economic system under consideration can be used. The model can take into account the uncertainty in the estimated values of the parameters or expert estimations. The model uses the multi-criteria approach based on the Pareto solutions.

Multilevel survival analysis of health inequalities in life expectancy

Directory of Open Access Journals (Sweden)

Merlo Juan

2009-08-01

Full Text Available Abstract Background The health status of individuals is determined by multiple factors operating at both micro and macro levels and the interactive effects of them. Measures of health inequalities should reflect such determinants explicitly through sources of levels and combining mean differences at group levels and the variation of individuals, for the benefits of decision making and intervention planning. Measures derived recently from marginal models such as beta-binomial and frailty survival, address this issue to some extent, but are limited in handling data with complex structures. Beta-binomial models were also limited in relation to measuring inequalities of life expectancy (LE directly. Methods We propose a multilevel survival model analysis that estimates life expectancy based on survival time with censored data. The model explicitly disentangles total health inequalities in terms of variance components of life expectancy compared to the source of variation at the level of individuals in households and parishes and so on, and estimates group differences of inequalities at the same time. Adjusted distributions of life expectancy by gender and by household socioeconomic level are calculated. Relative and absolute health inequality indices are derived based on model estimates. The model based analysis is illustrated on a large Swedish cohort of 22,680 men and 26,474 women aged 65–69 in 1970 and followed up for 30 years. Model based inequality measures are compared to the conventional calculations. Results Much variation of life expectancy is observed at individual and household levels. Contextual effects at Parish and Municipality level are negligible. Women have longer life expectancy than men and lower inequality. There is marked inequality by the level of household socioeconomic status measured by the median life expectancy in each socio-economic group and the variation in life expectancy within each group. Conclusion Multilevel

High-order UWB pulses scheme to generate multilevel modulation formats based on incoherent optical sources.

Science.gov (United States)

Bolea, Mario; Mora, José; Ortega, Beatriz; Capmany, José

2013-11-18

We present a high-order UWB pulses generator based on a microwave photonic filter which provides a set of positive and negative samples by using the slicing of an incoherent optical source and the phase inversion in a Mach-Zehnder modulator. The simple scalability and high reconfigurability of the system permit a better accomplishment of the FCC requirements. Moreover, the proposed scheme permits an easy adaptation to pulse amplitude modulation, bi phase modulation, pulse shape modulation and pulse position modulation. The flexibility of the scheme for being adaptable to multilevel modulation formats permits to increase the transmission bit rate by using hybrid modulation formats.

Multi-level governance in EU climate law

NARCIS (Netherlands)

Vedder, Hans; Woerdman, Edwin; Roggenkamp, Martha; Holwerda, Marijn

2015-01-01

This chapter analyses the multi-level governance in EU climate law; it connects the international arena, with EU and national decision-making and relates climate change considerations to competitiveness concerns.

CoR's White Paper on Multilevel Governance - Advantages and Disadvantages

OpenAIRE

Gal, Diana; Brie, Mircea

2011-01-01

By the multilevel governance concept we can see the European Union as a political system with interconnected institutions that exist at multiple levels with unique policy features. The White Paper on Multilevel Governance reflects the determination to "Build Europe in partnership" and sets two main strategic objectives: encouraging participation in the European process and reinforcing the efficiency of Community action. The fact that public interest in European elections is decreasing, whils...

A Randomized Controlled Trial of Low-Dose Tranexamic Acid versus Placebo to Reduce Red Blood Cell Transfusion During Complex Multilevel Spine Fusion Surgery.

Science.gov (United States)

Carabini, Louanne M; Moreland, Natalie C; Vealey, Ryan J; Bebawy, John F; Koski, Tyler R; Koht, Antoun; Gupta, Dhanesh K; Avram, Michael J

2018-02-01

Multilevel spine fusion surgery for adult deformity correction is associated with significant blood loss and coagulopathy. Tranexamic acid reduces blood loss in high-risk surgery, but the efficacy of a low-dose regimen is unknown. Sixty-one patients undergoing multilevel complex spinal fusion with and without osteotomies were randomly assigned to receive low-dose tranexamic acid (10 mg/kg loading dose, then 1 mg·kg -1 ·hr -1 throughout surgery) or placebo. The primary outcome was the total volume of red blood cells transfused intraoperatively. Thirty-one patients received tranexamic acid, and 30 patients received placebo. Patient demographics, risk of major transfusion, preoperative hemoglobin, and surgical risk of the 2 groups were similar. There was a significant decrease in total volume of red blood cells transfused (placebo group median 1460 mL vs. tranexamic acid group 1140 mL; median difference 463 mL, 95% confidence interval 15 to 914 mL, P = 0.034), with a decrease in cell saver transfusion (placebo group median 490 mL vs. tranexamic acid group 256 mL; median difference 166 mL, 95% confidence interval 0 to 368 mL, P = 0.042). The decrease in packed red blood cell transfusion did not reach statistical significance (placebo group median 1050 mL vs. tranexamic acid group 600 mL; median difference 300 mL, 95% confidence interval 0 to 600 mL, P = 0.097). Our results support the use of low-dose tranexamic acid during complex multilevel spine fusion surgery to decrease total red blood cell transfusion. Copyright © 2017 Elsevier Inc. All rights reserved.

Multilevel modeling and panel data analysis in educational research (Case study: National examination data senior high school in West Java)

Science.gov (United States)

Zulvia, Pepi; Kurnia, Anang; Soleh, Agus M.

2017-03-01

Individual and environment are a hierarchical structure consist of units grouped at different levels. Hierarchical data structures are analyzed based on several levels, with the lowest level nested in the highest level. This modeling is commonly call multilevel modeling. Multilevel modeling is widely used in education research, for example, the average score of National Examination (UN). While in Indonesia UN for high school student is divided into natural science and social science. The purpose of this research is to develop multilevel and panel data modeling using linear mixed model on educational data. The first step is data exploration and identification relationships between independent and dependent variable by checking correlation coefficient and variance inflation factor (VIF). Furthermore, we use a simple model approach with highest level of the hierarchy (level-2) is regency/city while school is the lowest of hierarchy (level-1). The best model was determined by comparing goodness-of-fit and checking assumption from residual plots and predictions for each model. Our finding that for natural science and social science, the regression with random effects of regency/city and fixed effects of the time i.e multilevel model has better performance than the linear mixed model in explaining the variability of the dependent variable, which is the average scores of UN.

Multilevel models in international business research

NARCIS (Netherlands)

Peterson, M.F.; Arregle, J-L.; Martin, Xavier

2012-01-01

Multiple-level (or mixed linear) modeling (MLM) can simultaneously test hypotheses at several levels of analysis (usually two or three), or control for confounding effects at one level while testing hypotheses at others. Advances in multi-level modeling allow increased precision in quantitative

Multilevel Modeling and Policy Development: Guidelines and Applications to Medical Travel

Science.gov (United States)

Garcia-Garzon, Eduardo; Zhukovsky, Peter; Haller, Elisa; Plakolm, Sara; Fink, David; Petrova, Dafina; Mahalingam, Vaishali; Menezes, Igor G.; Ruggeri, Kai

2016-01-01

Medical travel has expanded rapidly in recent years, resulting in new markets and increased access to medical care. Whereas several studies investigated the motives of individuals seeking healthcare abroad, the conventional analytical approach is limited by substantial caveats. Classical techniques as found in the literature cannot provide sufficient insight due to the nested nature of data generated. The application of adequate analytical techniques, specifically multilevel modeling, is scarce to non-existent in the context of medical travel. This study introduces the guidelines for application of multilevel techniques in public health research by presenting an application of multilevel modeling in analyzing the decision-making patterns of potential medical travelers. Benefits and potential limitations are discussed. PMID:27252672

Multilevel Modeling and Policy Development: Guidelines and Applications to Medical Travel.

Science.gov (United States)

Garcia-Garzon, Eduardo; Zhukovsky, Peter; Haller, Elisa; Plakolm, Sara; Fink, David; Petrova, Dafina; Mahalingam, Vaishali; Menezes, Igor G; Ruggeri, Kai

2016-01-01

Medical travel has expanded rapidly in recent years, resulting in new markets and increased access to medical care. Whereas several studies investigated the motives of individuals seeking healthcare abroad, the conventional analytical approach is limited by substantial caveats. Classical techniques as found in the literature cannot provide sufficient insight due to the nested nature of data generated. The application of adequate analytical techniques, specifically multilevel modeling, is scarce to non-existent in the context of medical travel. This study introduces the guidelines for application of multilevel techniques in public health research by presenting an application of multilevel modeling in analyzing the decision-making patterns of potential medical travelers. Benefits and potential limitations are discussed.

Pulse design for multilevel systems by utilizing Lie transforms

Science.gov (United States)

Kang, Yi-Hao; Chen, Ye-Hong; Shi, Zhi-Cheng; Huang, Bi-Hua; Song, Jie; Xia, Yan

2018-03-01

We put forward a scheme to design pulses to manipulate multilevel systems with Lie transforms. A formula to reverse construct a control Hamiltonian is given and is applied in pulse design in the three- and four-level systems as examples. To demonstrate the validity of the scheme, we perform numerical simulations, which show the population transfers for cascaded three-level and N -type four-level Rydberg atoms can be completed successfully with high fidelities. Therefore, the scheme may benefit quantum information tasks based on multilevel systems.

A multilevel simultaneous equations model for within-cluster dynamic effects, with an application to reciprocal parent–child and sibling effects

OpenAIRE

Fiona Steele; Jon Rasbash; Jennifer Jenkins

2013-01-01

There has been substantial interest in the social and health sciences in the reciprocal causal influences that people in close relationships have on one another. Most research has considered reciprocal processes involving only 2 units, although many social relationships of interest occur within a larger group (e.g., families, work groups, peer groups, classrooms). This article presents a general longitudinal multilevel modeling framework for the simultaneous estimation of reciprocal relations...

Harmonic elimination technique for a single-phase multilevel converter with unequal DC link voltage levels

DEFF Research Database (Denmark)

Ghasemi, N.; Zare, F.; Boora, A.A.

2012-01-01

Multilevel converters, because of the benefits they attract in generating high quality output voltage, are used in several applications. Various modulation and control techniques are introduced by several researchers to control the output voltage of the multilevel converters like space vector...... modulation and harmonic elimination (HE) methods. Multilevel converters may have a DC link with equal or unequal DC voltages. In this study a new HE technique based on the HE method is proposed for multilevel converters with unequal DC link voltage. The DC link voltage levels are considered as additional...

Multilevel (mental) health promotion as social innovation in peripheral areas of Denmark

DEFF Research Database (Denmark)

Delica, Kristian Nagel

, bureaucratic level over the front line welfare professionals’ practices to the young mother’s experiences. The paper aligns a multilevel approach to theories of social innovation. This forms a fundament for discussing ‘horizontal’ and ‘vertical’ multilevel health promotion and analysing the interwoven...

Cost-utility analysis of minimally invasive versus open multilevel hemilaminectomy for lumbar stenosis.

Science.gov (United States)

Parker, Scott L; Adogwa, Owoicho; Davis, Brandon J; Fulchiero, Erin; Aaronson, Oran; Cheng, Joseph; Devin, Clinton J; McGirt, Matthew J

2013-02-01

Two-year cost-utility study comparing minimally invasive (MIS) versus open multilevel hemilaminectomy in patients with degenerative lumbar spinal stenosis. The objective of the study was to determine whether MIS versus open multilevel hemilaminectomy for degenerative lumbar spinal stenosis is a cost-effective advancement in lumbar decompression surgery. MIS-multilevel hemilaminectomy for degenerative lumbar spinal stenosis allows for effective treatment of back and leg pain while theoretically minimizing blood loss, tissue injury, and postoperative recovery. No studies have evaluated comprehensive healthcare costs associated with multilevel hemilaminectomy procedures, nor assessed cost-effectiveness of MIS versus open multilevel hemilaminectomy. Fifty-four consecutive patients with lumbar stenosis undergoing multilevel hemilaminectomy through an MIS paramedian tubular approach (n=27) versus midline open approach (n=27) were included. Total back-related medical resource utilization, missed work, and health state values [quality adjusted life years (QALYs), calculated from EuroQuol-5D with US valuation] were assessed after 2-year follow-up. Two-year resource use was multiplied by unit costs based on Medicare national allowable payment amounts (direct cost) and work-day losses were multiplied by the self-reported gross-of-tax wage rate (indirect cost). Difference in mean total cost per QALY gained for MIS versus open hemilaminectomy was assessed as incremental cost-effectiveness ratio (ICER: COST(MIS)-COST(OPEN)/QALY(MIS)-QALY(OPEN)). MIS versus open cohorts were similar at baseline. MIS and open hemilaminectomy were associated with an equivalent cumulative gain of 0.72 QALYs 2 years after surgery. Mean direct medical costs, indirect societal costs, and total 2-year cost ($23,109 vs. $25,420; P=0.21) were similar between MIS and open hemilaminectomy. MIS versus open approach was associated with similar total costs and utility, making it a cost equivalent technology

On the Multilevel Nature of Meta-Analysis: A Tutorial, Comparison of Software Programs, and Discussion of Analytic Choices.

Science.gov (United States)

Pastor, Dena A; Lazowski, Rory A

2018-01-01

The term "multilevel meta-analysis" is encountered not only in applied research studies, but in multilevel resources comparing traditional meta-analysis to multilevel meta-analysis. In this tutorial, we argue that the term "multilevel meta-analysis" is redundant since all meta-analysis can be formulated as a special kind of multilevel model. To clarify the multilevel nature of meta-analysis the four standard meta-analytic models are presented using multilevel equations and fit to an example data set using four software programs: two specific to meta-analysis (metafor in R and SPSS macros) and two specific to multilevel modeling (PROC MIXED in SAS and HLM). The same parameter estimates are obtained across programs underscoring that all meta-analyses are multilevel in nature. Despite the equivalent results, not all software programs are alike and differences are noted in the output provided and estimators available. This tutorial also recasts distinctions made in the literature between traditional and multilevel meta-analysis as differences between meta-analytic choices, not between meta-analytic models, and provides guidance to inform choices in estimators, significance tests, moderator analyses, and modeling sequence. The extent to which the software programs allow flexibility with respect to these decisions is noted, with metafor emerging as the most favorable program reviewed.

The Design Model of Multilevel Estimation Means for Students’ Competence Assessment at Technical Higher School

Directory of Open Access Journals (Sweden)

O. F. Shikhova

2012-01-01

Full Text Available The paper considers the research findings aimed at the developing the new quality testing technique for students assessment at Technical Higher School. The model of multilevel estimation means is provided for diagnosing the level of general cultural and professional competences of students doing a bachelor degree in technological fields. The model implies the integrative character of specialists training - the combination of both the psycho-pedagogic (invariable and engineering (variable components, as well as the qualimetric approach substantiating the system of students competence estimation and providing the most adequate assessment means. The principles of designing the multilevel estimation means are defined along with the methodology approaches to their implementation. For the reasonable selection of estimation means, the system of quality criteria is proposed by the authors, being based on the group expert assessment. The research findings can be used for designing the competence-oriented estimation means. 

Detecting groups of coevolving positions in a molecule: a clustering approach

Directory of Open Access Journals (Sweden)

Galtier Nicolas

2007-11-01

Full Text Available Abstract Background Although the patterns of co-substitutions in RNA is now well characterized, detection of coevolving positions in proteins remains a difficult task. It has been recognized that the signal is typically weak, due to the fact that (i amino-acid are characterized by various biochemical properties, so that distinct amino acids changes are not functionally equivalent, and (ii a given mutation can be compensated by more than one mutation, at more than one position. Results We present a new method based on phylogenetic substitution mapping. The two above-mentioned problems are addressed by (i the introduction of a weighted mapping, which accounts for the biochemical effects (volume, polarity, charge of amino-acid changes, (ii the use of a clustering approach to detect groups of coevolving sites of virtually any size, and (iii the distinction between biochemical compensation and other coevolutionary mechanisms. We apply this methodology to a previously studied data set of bacterial ribosomal RNA, and to three protein data sets (myoglobin of vertebrates, S-locus Receptor Kinase and Methionine Amino-Peptidase. Conclusion We succeed in detecting groups of sites which significantly depart the null hypothesis of independence. Group sizes range from pairs to groups of size ≃ 10, depending on the substitution weights used. The structural and functional relevance of these groups of sites are assessed, and the various evolutionary processes potentially generating correlated substitution patterns are discussed.

The multi-level perspective analysis: Indonesia geothermal energy transition study

Science.gov (United States)

Wisaksono, A.; Murphy, J.; Sharp, J. H.; Younger, P. L.

2018-01-01

The study adopts a multi-level perspective in technology transition to analyse how the transition process in the development of geothermal energy in Indonesia is able to compete against the incumbent fossil-fuelled energy sources. Three levels of multi-level perspective are socio-technical landscape (ST-landscape), socio-technical regime (ST-regime) and niche innovations in Indonesia geothermal development. The identification, mapping and analysis of the dynamic relationship between each level are the important pillars of the multi-level perspective framework. The analysis considers the set of rules, actors and controversies that may arise in the technological transition process. The identified geothermal resource risks are the basis of the emerging geothermal technological innovations in Indonesian geothermal. The analysis of this study reveals the transition pathway, which yields a forecast for the Indonesian geothermal technology transition in the form of scenarios and probable impacts.

Multi-stage decoding of multi-level modulation codes

Science.gov (United States)

Lin, Shu; Kasami, Tadao; Costello, Daniel J., Jr.

1991-01-01

Various types of multi-stage decoding for multi-level modulation codes are investigated. It is shown that if the component codes of a multi-level modulation code and types of decoding at various stages are chosen properly, high spectral efficiency and large coding gain can be achieved with reduced decoding complexity. Particularly, it is shown that the difference in performance between the suboptimum multi-stage soft-decision maximum likelihood decoding of a modulation code and the single-stage optimum soft-decision decoding of the code is very small, only a fraction of dB loss in signal to noise ratio at a bit error rate (BER) of 10(exp -6).

Relationships between Religion and Two Forms of Homonegativity in Europe—A Multilevel Analysis of Effects of Believing, Belonging and Religious Practice

Science.gov (United States)

Doebler, Stefanie

2015-01-01

This paper examines relationships between religion and two forms of homonegativity across 43 European countries using a bivariate response binary logistic multilevel model. The model analyzes effects of religious believing, belonging and practice on two response variables: a) a moral rejection of homosexuality as a practice and b) intolerance toward homosexuals as a group. The findings indicate that both forms of homonegativity are prevalent in Europe. Traditional doctrinal religious believing (belief in a personal God) is positively related to a moral rejection of homosexuality but to a much lesser extent associated with intolerance toward homosexuals as a group. Members of religious denominations are more likely than non-members to reject homosexuality as morally wrong and to reject homosexuals as neighbors. The analysis found significant differences between denominations that are likely context-dependent. Attendance at religious services is positively related to homonegativity in a majority of countries. The findings vary considerably across countries: Religion is more strongly related to homonegativity in Western than in Eastern Europe. In the post-soviet countries homonegativity appears to be largely a secular phenomenon. National contexts of high religiosity, high perceived government corruption, high income inequality and shortcomings in the implementation of gay rights in the countries’ legislations are statistically related to higher levels of both moralistic homonegativity and intolerance toward homosexuals as a group. PMID:26247352

Relationships between Religion and Two Forms of Homonegativity in Europe--A Multilevel Analysis of Effects of Believing, Belonging and Religious Practice.

Science.gov (United States)

Doebler, Stefanie

2015-01-01

This paper examines relationships between religion and two forms of homonegativity across 43 European countries using a bivariate response binary logistic multilevel model. The model analyzes effects of religious believing, belonging and practice on two response variables: a) a moral rejection of homosexuality as a practice and b) intolerance toward homosexuals as a group. The findings indicate that both forms of homonegativity are prevalent in Europe. Traditional doctrinal religious believing (belief in a personal God) is positively related to a moral rejection of homosexuality but to a much lesser extent associated with intolerance toward homosexuals as a group. Members of religious denominations are more likely than non-members to reject homosexuality as morally wrong and to reject homosexuals as neighbors. The analysis found significant differences between denominations that are likely context-dependent. Attendance at religious services is positively related to homonegativity in a majority of countries. The findings vary considerably across countries: Religion is more strongly related to homonegativity in Western than in Eastern Europe. In the post-soviet countries homonegativity appears to be largely a secular phenomenon. National contexts of high religiosity, high perceived government corruption, high income inequality and shortcomings in the implementation of gay rights in the countries' legislations are statistically related to higher levels of both moralistic homonegativity and intolerance toward homosexuals as a group.

Relationships between Religion and Two Forms of Homonegativity in Europe--A Multilevel Analysis of Effects of Believing, Belonging and Religious Practice.

Directory of Open Access Journals (Sweden)

Stefanie Doebler

Full Text Available This paper examines relationships between religion and two forms of homonegativity across 43 European countries using a bivariate response binary logistic multilevel model. The model analyzes effects of religious believing, belonging and practice on two response variables: a a moral rejection of homosexuality as a practice and b intolerance toward homosexuals as a group. The findings indicate that both forms of homonegativity are prevalent in Europe. Traditional doctrinal religious believing (belief in a personal God is positively related to a moral rejection of homosexuality but to a much lesser extent associated with intolerance toward homosexuals as a group. Members of religious denominations are more likely than non-members to reject homosexuality as morally wrong and to reject homosexuals as neighbors. The analysis found significant differences between denominations that are likely context-dependent. Attendance at religious services is positively related to homonegativity in a majority of countries. The findings vary considerably across countries: Religion is more strongly related to homonegativity in Western than in Eastern Europe. In the post-soviet countries homonegativity appears to be largely a secular phenomenon. National contexts of high religiosity, high perceived government corruption, high income inequality and shortcomings in the implementation of gay rights in the countries' legislations are statistically related to higher levels of both moralistic homonegativity and intolerance toward homosexuals as a group.

Estimating the Multilevel Rasch Model: With the lme4 Package

Directory of Open Access Journals (Sweden)

Harold Doran

2007-02-01

Full Text Available Traditional Rasch estimation of the item and student parameters via marginal maximum likelihood, joint maximum likelihood or conditional maximum likelihood, assume individuals in clustered settings are uncorrelated and items within a test that share a grouping structure are also uncorrelated. These assumptions are often violated, particularly in educational testing situations, in which students are grouped into classrooms and many test items share a common grouping structure, such as a content strand or a reading passage. Consequently, one possible approach is to explicitly recognize the clustered nature of the data and directly incorporate random effects to account for the various dependencies. This article demonstrates how the multilevel Rasch model can be estimated using the functions in R for mixed-effects models with crossed or partially crossed random effects. We demonstrate how to model the following hierarchical data structures: a individuals clustered in similar settings (e.g., classrooms, schools, b items nested within a particular group (such as a content strand or a reading passage, and c how to estimate a teacher × content strand interaction.

Validation of Multilevel Constructs: Validation Methods and Empirical Findings for the EDI

Science.gov (United States)

Forer, Barry; Zumbo, Bruno D.

2011-01-01

The purposes of this paper are to highlight the foundations of multilevel construct validation, describe two methodological approaches and associated analytic techniques, and then apply these approaches and techniques to the multilevel construct validation of a widely-used school readiness measure called the Early Development Instrument (EDI;…

Group Systematic Desensitization Versus Covert Positive Reinforcement in the Reduction of Test Anxiety

Science.gov (United States)

Kostka, Marion P.; Galassi, John P.

1974-01-01

The study compared modified versions of systematic desensitization and covert positive reinforcement to a no-treatment control condition in the reduction of test anxiety. On an anagrams performance test, the covert reinforcement and control groups were superior to the desensitization group. (Author)

Analysing the effect of area of residence over the life course in multilevel epidemiology.

Science.gov (United States)

Naess, Oyvind; Leyland, Alastair H

2010-11-01

In this paper we present multilevel models of individuals' residential history at multiple time points through the life course and their application and discuss some advantages and disadvantages for their use in epidemiological studies. Literature review of research using longitudinal multilevel models in studies of neighbourhood effects, statistical multilevel models that take individuals' residential history into account, and the application of these models in the Oslo mortality study. Measures of variance have been used to investigate the contextual impact of membership to collectives, such as area of residence, at several time points. The few longitudinal multilevel models that have been used suggest that early life area of residence may have an effect on mortality independently of residence later in life although the proportion of variation attributable to area level is small compared to individual level. The following multilevel models have been developed: simple multilevel models for each year separately, a multiple membership model, a cross-classified model, and finally a correlated cross-classified model. These models have different assumptions regarding the timing of influence through the life course. To fully recognise the origin of adult chronic diseases, factors at all stages of the life course at both individual and area level needs to be considered in order to avoid biased estimates. Important challenges in making life course residential data available for research and assessing how changing administrative coding over time reflect contextual impact need to be overcome before these models can be implemented as normal practice in multilevel epidemiology.

MULTILEVEL SYNCRETISM AND THE EVOLUTION OF ...

African Journals Online (AJOL)

MULTILEVEL SYNCRETISM AND THE EVOLUTION OF AFRIKAANS. PERIPHRASTIC POSSESSIVES WITH SE. Paul T. Roberge. University or North Carolina, Chapel ..... van hem ook een bees gestoole ben ook drie volk !lli!. spoor en ook ben daar bij Bester een velds waage uijt gespanne gewees heef zulle de man zijn ...

Positive Affect as a Source of Resilience for Women in Chronic Pain

OpenAIRE

Zautra, Alez J.; Johnson, Lisa M.; Davis, Mary C.

2005-01-01

A sample of 124 women with osteoarthritis (OA) and/or fibromyalgia (FMS) completed initial assessments for demographic data, health status, and personality traits and 10 to 12 weekly interviews regarding pain, stress, negative affect, and positive affect. Multilevel modeling analyses indicated that weekly elevations of pain and stress predicted increases in negative affect. Both higher weekly positive affect as well as greater positive affect on average resulted in lower negative affect both ...

Adjusting to Social Change - A Multi-Level Analysis in Three Cultures

Science.gov (United States)

2013-08-01

example, coping may be more collective in collectivist , compared to individualist , societies (Chang & Sivam, 2004). Some cultures have a greater sense...AFRL-AFOSR-UK-TR-2013-0041 Adjusting to Social Change - A multi-level Analysis in three cultures Prof Robin Goodwin...COVERED (From – To) 23 May 2012 – 22 May 2013 4. TITLE AND SUBTITLE Adjusting to Social Change - A multi-level Analysis in three cultures

Space vector-based modeling and control of a modular multilevel converter in HVDC applications

DEFF Research Database (Denmark)

Bonavoglia, M.; Casadei, G.; Zarri, L.

2013-01-01

Modular multilevel converter (MMC) is an emerging multilevel topology for high-voltage applications that has been developed in recent years. In this paper, the modeling and the control of MMCs are restated in terms of space vectors, which may allow a deeper understanding of the converter behavior....... As a result, a control scheme for three-phase MMCs based on the previous theoretical analysis is presented. Numerical simulations are used to test its feasibility.......Modular multilevel converter (MMC) is an emerging multilevel topology for high-voltage applications that has been developed in recent years. In this paper, the modeling and the control of MMCs are restated in terms of space vectors, which may allow a deeper understanding of the converter behavior...

Differential effects of arousal in positive and negative autobiographical memories.

Science.gov (United States)

Ford, Jaclyn Hennessey; Addis, Donna Rose; Giovanello, Kelly S

2012-01-01

Autobiographical memories are characterised by a range of emotions and emotional reactions. Recent research has demonstrated that differences in emotional valence (positive vs. negative emotion) and arousal (the degree of emotional intensity) differentially influence the retrieved memory narrative. Although the mnemonic effects of valence and arousal have both been heavily studied, it is currently unclear whether the effects of emotional arousal are equivalent for positive and negative autobiographical events. In the current study, multilevel models were used to examine differential effects of emotional valence and arousal on the richness of autobiographical memory retrieval both between and within subjects. Thirty-four young adults were asked to retrieve personal autobiographical memories associated with popular musical cues and to rate the valence, arousal and richness of these events. The multilevel analyses identified independent influences of valence and intensity upon retrieval characteristics at the within- and between-subject levels. In addition, the within-subject interactions between valence and arousal highlighted differential effects of arousal for positive and negative memories. These findings have important implications for future studies of emotion and memory, highlighting the importance of considering both valence and arousal when examining the role emotion plays in the richness of memory representation.

Cities, Europeanization and Multi-level Governance: Governing Climate Change through Transnational Municipal Networks

NARCIS (Netherlands)

Kern, K.; Bulkeley, H.

2009-01-01

This article focuses on a variant of multi-level governance and Europeanization, i.e. the transnational networking of local authorities. Focusing on local climate change policy, the article examines how transnational municipal networks (TMNs) govern in the context of multi-level European governance.

The Extrapolation-Accelerated Multilevel Aggregation Method in PageRank Computation

Directory of Open Access Journals (Sweden)

Bing-Yuan Pu

2013-01-01

Full Text Available An accelerated multilevel aggregation method is presented for calculating the stationary probability vector of an irreducible stochastic matrix in PageRank computation, where the vector extrapolation method is its accelerator. We show how to periodically combine the extrapolation method together with the multilevel aggregation method on the finest level for speeding up the PageRank computation. Detailed numerical results are given to illustrate the behavior of this method, and comparisons with the typical methods are also made.

Multi-level methods and approximating distribution functions

International Nuclear Information System (INIS)

Wilson, D.; Baker, R. E.

2016-01-01

Biochemical reaction networks are often modelled using discrete-state, continuous-time Markov chains. System statistics of these Markov chains usually cannot be calculated analytically and therefore estimates must be generated via simulation techniques. There is a well documented class of simulation techniques known as exact stochastic simulation algorithms, an example of which is Gillespie’s direct method. These algorithms often come with high computational costs, therefore approximate stochastic simulation algorithms such as the tau-leap method are used. However, in order to minimise the bias in the estimates generated using them, a relatively small value of tau is needed, rendering the computational costs comparable to Gillespie’s direct method. The multi-level Monte Carlo method (Anderson and Higham, Multiscale Model. Simul. 10:146–179, 2012) provides a reduction in computational costs whilst minimising or even eliminating the bias in the estimates of system statistics. This is achieved by first crudely approximating required statistics with many sample paths of low accuracy. Then correction terms are added until a required level of accuracy is reached. Recent literature has primarily focussed on implementing the multi-level method efficiently to estimate a single system statistic. However, it is clearly also of interest to be able to approximate entire probability distributions of species counts. We present two novel methods that combine known techniques for distribution reconstruction with the multi-level method. We demonstrate the potential of our methods using a number of examples.

Multi-level methods and approximating distribution functions

Energy Technology Data Exchange (ETDEWEB)

Wilson, D., E-mail: daniel.wilson@dtc.ox.ac.uk; Baker, R. E. [Mathematical Institute, University of Oxford, Radcliffe Observatory Quarter, Woodstock Road, Oxford, OX2 6GG (United Kingdom)

2016-07-15

Biochemical reaction networks are often modelled using discrete-state, continuous-time Markov chains. System statistics of these Markov chains usually cannot be calculated analytically and therefore estimates must be generated via simulation techniques. There is a well documented class of simulation techniques known as exact stochastic simulation algorithms, an example of which is Gillespie’s direct method. These algorithms often come with high computational costs, therefore approximate stochastic simulation algorithms such as the tau-leap method are used. However, in order to minimise the bias in the estimates generated using them, a relatively small value of tau is needed, rendering the computational costs comparable to Gillespie’s direct method. The multi-level Monte Carlo method (Anderson and Higham, Multiscale Model. Simul. 10:146–179, 2012) provides a reduction in computational costs whilst minimising or even eliminating the bias in the estimates of system statistics. This is achieved by first crudely approximating required statistics with many sample paths of low accuracy. Then correction terms are added until a required level of accuracy is reached. Recent literature has primarily focussed on implementing the multi-level method efficiently to estimate a single system statistic. However, it is clearly also of interest to be able to approximate entire probability distributions of species counts. We present two novel methods that combine known techniques for distribution reconstruction with the multi-level method. We demonstrate the potential of our methods using a number of examples.

Democracy and self-rated health across 67 countries: A multilevel analysis.

Science.gov (United States)

Krueger, Patrick M; Dovel, Kathryn; Denney, Justin T

2015-10-01

Existing research has found a positive association between countries' level of democratic governance and the health of their populations, although that research is limited by the use of data from small numbers of high-income countries or aggregate data that do not assess individual-level health outcomes. We extend prior research by using multilevel World Health Survey (2002-2004) data on 313,554 individuals in 67 countries, and find that the positive association between democratic governance and self-rated health persists after adjusting for both individual- and country-level confounders. However, the mechanisms linking democracy and self-rated health remain unclear. Individual-level measures of socioeconomic status, and country-level measures of economic inequality and investments in public health and education, do not significantly mediate the association between democratic governance and self-rated health. The persistent association between democratic governance and health suggests that the political organization of societies may be an important upstream determinant of population health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Single-Level and Multilevel Mediation Analysis

Science.gov (United States)

Tofighi, Davood; Thoemmes, Felix

2014-01-01

Mediation analysis is a statistical approach used to examine how the effect of an independent variable on an outcome is transmitted through an intervening variable (mediator). In this article, we provide a gentle introduction to single-level and multilevel mediation analyses. Using single-level data, we demonstrate an application of structural…

Multi-Level Formation of Complex Software Systems

Directory of Open Access Journals (Sweden)

Hui Li

2016-05-01

Full Text Available We present a multi-level formation model for complex software systems. The previous works extract the software systems to software networks for further studies, but usually investigate the software networks at the class level. In contrast to these works, our treatment of software systems as multi-level networks is more realistic. In particular, the software networks are organized by three levels of granularity, which represents the modularity and hierarchy in the formation process of real-world software systems. More importantly, simulations based on this model have generated more realistic structural properties of software networks, such as power-law, clustering and modularization. On the basis of this model, how the structure of software systems effects software design principles is then explored, and it could be helpful for understanding software evolution and software engineering practices.

Health reforms as examples of multilevel interventions in cancer care.

Science.gov (United States)

Flood, Ann B; Fennell, Mary L; Devers, Kelly J

2012-05-01

To increase access and improve system quality and efficiency, President Obama signed the Patient Protection and Affordable Care Act with sweeping changes to the nation's health-care system. Although not intended to be specific to cancer, the act's implementation will profoundly impact cancer care. Its components will influence multiple levels of the health-care environment including states, communities, health-care organizations, and individuals seeking care. To illustrate these influences, two reforms are considered: 1) accountable care organizations and 2) insurance-based reforms to gather evidence about effectiveness. We discuss these reforms using three facets of multilevel interventions: 1) their intended and unintended consequences, 2) the importance of timing, and 3) their implications for cancer. The success of complex health reforms requires understanding the scientific basis and evidence for carrying out such multilevel interventions. Conversely and equally important, successful implementation of multilevel interventions depends on understanding the political setting and goals of health-care reform.

Phase reconstruction by a multilevel iteratively regularized Gauss–Newton method

International Nuclear Information System (INIS)

Langemann, Dirk; Tasche, Manfred

2008-01-01

In this paper we consider the numerical solution of a phase retrieval problem for a compactly supported, linear spline f : R → C with the Fourier transform f-circumflex, where values of |f| and |f-circumflex| at finitely many equispaced nodes are given. The unknown phases of complex spline coefficients fulfil a well-structured system of nonlinear equations. Thus the phase reconstruction leads to a nonlinear inverse problem, which is solved by a multilevel strategy and iterative Tikhonov regularization. The multilevel strategy concentrates the main effort of the solution of the phase retrieval problem in the coarse, less expensive levels and provides convenient initial guesses at the next finer level. On each level, the corresponding nonlinear system is solved by an iteratively regularized Gauss–Newton method. The multilevel strategy is motivated by convergence results of IRGN. This method is applicable to a wide range of examples as shown in several numerical tests for noiseless and noisy data

Framing Negotiation: Dynamics of Epistemological and Positional Framing in Small Groups during Scientific Modeling

Science.gov (United States)

Shim, Soo-Yean; Kim, Heui-Baik

2018-01-01

In this study, we examined students' epistemological and positional framing during small group scientific modeling to explore their context-dependent perceptions about knowledge, themselves, and others. We focused on two small groups of Korean eighth-grade students who participated in six modeling activities about excretion. The two groups were…

Doing Good Again? A Multilevel Institutional Perspective on Corporate Environmental Responsibility and Philanthropic Strategy

Science.gov (United States)

Liu, Wei; Wei, Qiao; Huang, Song-Qin

2017-01-01

This study investigates the relationship between corporate environmental responsibility and corporate philanthropy. Using a sample of Chinese listed firms from 2008 to 2013, this paper examines the role of corporate environmental responsibility in corporate philanthropy and the moderating influence of the institutional environment using multilevel analysis. The results show that corporate eco-friendly events are positively associated with corporate philanthropic strategy to a significant degree. Provincial-level government intervention positively moderate the positive relationship between eco-friendly events and corporate philanthropy and government corruption is negatively moderate the relationship. All these results are robust according to robustness checks. These findings provide a new perspective on corporate philanthropic strategy as a means to obtain critical resources from the government in order to compensate for the loss made on environmental responsibility. Moreover, the institutional environment is proved here to play an important role in corporate philanthropic strategy. PMID:29064451

Doing Good Again? A Multilevel Institutional Perspective on Corporate Environmental Responsibility and Philanthropic Strategy.

Science.gov (United States)

Liu, Wei; Wei, Qiao; Huang, Song-Qin; Tsai, Sang-Bing

2017-10-24

This study investigates the relationship between corporate environmental responsibility and corporate philanthropy. Using a sample of Chinese listed firms from 2008 to 2013, this paper examines the role of corporate environmental responsibility in corporate philanthropy and the moderating influence of the institutional environment using multilevel analysis. The results show that corporate eco-friendly events are positively associated with corporate philanthropic strategy to a significant degree. Provincial-level government intervention positively moderate the positive relationship between eco-friendly events and corporate philanthropy and government corruption is negatively moderate the relationship. All these results are robust according to robustness checks. These findings provide a new perspective on corporate philanthropic strategy as a means to obtain critical resources from the government in order to compensate for the loss made on environmental responsibility. Moreover, the institutional environment is proved here to play an important role in corporate philanthropic strategy.

Doing Good Again? A Multilevel Institutional Perspective on Corporate Environmental Responsibility and Philanthropic Strategy

Directory of Open Access Journals (Sweden)

Wei Liu

2017-10-01

Full Text Available This study investigates the relationship between corporate environmental responsibility and corporate philanthropy. Using a sample of Chinese listed firms from 2008 to 2013, this paper examines the role of corporate environmental responsibility in corporate philanthropy and the moderating influence of the institutional environment using multilevel analysis. The results show that corporate eco-friendly events are positively associated with corporate philanthropic strategy to a significant degree. Provincial-level government intervention positively moderate the positive relationship between eco-friendly events and corporate philanthropy and government corruption is negatively moderate the relationship. All these results are robust according to robustness checks. These findings provide a new perspective on corporate philanthropic strategy as a means to obtain critical resources from the government in order to compensate for the loss made on environmental responsibility. Moreover, the institutional environment is proved here to play an important role in corporate philanthropic strategy.

Explaining Differences in Subjective Well-Being Across 33 Nations Using Multilevel Models: Universal Personality, Cultural Relativity, and National Income.

Science.gov (United States)

Cheng, Cecilia; Cheung, Mike W-L; Montasem, Alex

2016-02-01

This multinational study simultaneously tested three prominent hypotheses--universal disposition, cultural relativity, and livability--that explained differences in subjective well-being across nations. We performed multilevel structural equation modeling to examine the hypothesized relationships at both individual and cultural levels in 33 nations. Participants were 6,753 university students (2,215 men; 4,403 women; 135 did not specify), and the average age of the entire sample was 20.97 years (SD = 2.39). Both individual- and cultural-level analyses supported the universal disposition and cultural relativity hypotheses by revealing significant associations of subjective well-being with Extraversion, Neuroticism, and independent self-construal. In addition, interdependent self-construal was positively related to life satisfaction at the individual level only, whereas aggregated negative affect was positively linked with aggregate levels of Extraversion and interdependent self-construal at the cultural level only. Consistent with the livability hypothesis, gross national income (GNI) was related to aggregate levels of negative affect and life satisfaction. There was also a quadratic relationship between GNI and aggregated positive affect. Our findings reveal that universal disposition, cultural self-construal, and national income can elucidate differences in subjective well-being, but the multilevel analyses advance the literature by yielding new findings that cannot be identified in studies using individual-level analyses alone. © 2014 Wiley Periodicals, Inc.

Impact of marriage on HIV/AIDS risk behaviors among impoverished, at-risk couples: A multilevel latent variable approach

OpenAIRE

Stein, JA; Nyamathi, A; Ullman, JB; Bentler, PM

2007-01-01

Studies among normative samples generally demonstrate a positive impact of marriage on health behaviors and other related attitudes. In this study, we examine the impact of marriage on HIV/AIDS risk behaviors and attitudes among impoverished, highly stressed, homeless couples, many with severe substance abuse problems. A multilevel analysis of 368 high-risk sexually intimate married and unmarried heterosexual couples assessed individual and couple-level effects on social support, substance us...

New multilevel inverter with reduction of switches and gate driver

Energy Technology Data Exchange (ETDEWEB)

Banaei, M.R., E-mail: m.banaei@azaruniv.ed [Electrical Engineering Department, Faculty of Engineering, Azarbaijan University of Tarbiat Moallem, Tabriz (Iran, Islamic Republic of); Salary, E. [Electrical Engineering Department, Faculty of Engineering, Azarbaijan University of Tarbiat Moallem, Tabriz (Iran, Islamic Republic of)

2011-02-15

This paper presents a novel topology for symmetrical cascade multilevel converter. The proposed circuit consists of series connected sub multilevel converters units and it can generate DC voltage levels similar to other topologies. The proposed topology results in reduction of switches number, losses, installation area and converter cost. This converter has been used in a Dynamic Voltage Restorer (DVR). Simulation results carried out by MATLAB/SIMULINK show the voltage injection capability of converter and the efficiency of its controller in compensating voltage sag and swell.

A multilevel control approach for a modular structured space platform

Science.gov (United States)

Chichester, F. D.; Borelli, M. T.

1981-01-01

A three axis mathematical representation of a modular assembled space platform consisting of interconnected discrete masses, including a deployable truss module, was derived for digital computer simulation. The platform attitude control system as developed to provide multilevel control utilizing the Gauss-Seidel second level formulation along with an extended form of linear quadratic regulator techniques. The objectives of the multilevel control are to decouple the space platform's spatial axes and to accommodate the modification of the platform's configuration for each of the decoupled axes.

An Internet of Things Based Multi-Level Privacy-Preserving Access Control for Smart Living

Directory of Open Access Journals (Sweden)

Usama Salama

2018-05-01

Full Text Available The presence of the Internet of Things (IoT in healthcare through the use of mobile medical applications and wearable devices allows patients to capture their healthcare data and enables healthcare professionals to be up-to-date with a patient’s status. Ambient Assisted Living (AAL, which is considered as one of the major applications of IoT, is a home environment augmented with embedded ambient sensors to help improve an individual’s quality of life. This domain faces major challenges in providing safety and security when accessing sensitive health data. This paper presents an access control framework for AAL which considers multi-level access and privacy preservation. We focus on two major points: (1 how to use the data collected from ambient sensors and biometric sensors to perform the high-level task of activity recognition; and (2 how to secure the collected private healthcare data via effective access control. We achieve multi-level access control by extending Public Key Infrastructure (PKI for secure authentication and utilizing Attribute-Based Access Control (ABAC for authorization. The proposed access control system regulates access to healthcare data by defining policy attributes over healthcare professional groups and data classes classifications. We provide guidelines to classify the data classes and healthcare professional groups and describe security policies to control access to the data classes.

An Integrative, Multilevel, and Transdisciplinary Research Approach to Challenges of Work, Family, and Health

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Bray, Jeremy W.; Kelly, Erin L.; Hammer, Leslie B.; Almeida, David M.; Dearing, James W.; King, Rosalind B.; Buxton, Orfeu M.

2013-01-01

Recognizing a need for rigorous, experimental research to support the efforts of workplaces and policymakers in improving the health and wellbeing of employees and their families, the National Institutes of Health and the Centers for Disease Control and Prevention formed the Work, Family & Health Network (WFHN). The WFHN is implementing an innovative multisite study with a rigorous experimental design (adaptive randomization, control groups), comprehensive multilevel measures, a novel and theoretically based intervention targeting the psychosocial work environment, and translational activities. This paper describes challenges and benefits of designing a multilevel and transdisciplinary research network that includes an effectiveness study to assess intervention effects on employees, families, and managers; a daily diary study to examine effects on family functioning and daily stress; a process study to understand intervention implementation; and translational research to understand and inform diffusion of innovation. Challenges were both conceptual and logistical, spanning all aspects of study design and implementation. In dealing with these challenges, however, the WFHN developed innovative, transdisciplinary, multi-method approaches to conducting workplace research that will benefit both the research and business communities. PMID:24618878

Toward A Multilevel Theory of Career Development: Advancing Human Resource Development Theory Building

Science.gov (United States)

Upton, Matthew G.; Egan, Toby Marshall

2007-01-01

The established limitations of career development (CD) theory and human resource development (HRD) theory building are addressed by expanding the framing of these issues to multilevel contexts. Multilevel theory building is an approach most effectively aligned with HRD literature and CD and HRD practice realities. An innovative approach multilevel…

Transformational Leadership and Incivility: A Multilevel and Longitudinal Test.

Science.gov (United States)

Bureau, Julien S; Gagné, Marylène; Morin, Alexandre J S; Mageau, Geneviève A

2017-10-01

This research examines group-level perceptions of transformational leadership (TFL) as negative longitudinal predictors of witnessing person-related (e.g., insults/affronts) and work-related (e.g., negation/intentional work overload) acts of incivility at work. Witnessing workplace incivility was also postulated to negatively predict employee need satisfaction. Data were collected among production employees in different Canadian plants of a major manufacturing company ( N = 344) who worked for 42 different managers ( M group size = 9.76). Two waves of data collection occurred 1 year apart. Results from multilevel analyses showed that workgroups where managers were perceived to engage in more frequent TFL behaviors reported reduced levels of person- and work-related incivility 1 year later. However, group-level incivility did not predict change in group-level need satisfaction 1 year later. At the individual level, results showed that witnessing higher levels of person-related incivility than one's colleagues predicted reduced satisfaction of the need for relatedness 1 year later. These longitudinal findings build upon previous literature by identifying TFL as a potential managerial strategy to reduce incivility in workgroups over time. They also show that mere exposure to workplace misbehavior still affects employees' adjustment, suggesting that every effort to reduce deviance in workplaces is worthwhile.

THE MODEL OF LIFELONG EDUCATION IN A TECHNICAL UNIVERSITY AS A MULTILEVEL EDUCATIONAL COMPLEX

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Svetlana V. Sergeyeva

2016-06-01

Full Text Available Introduction: the current leading trend of the educational development is characterised by its continuity. Institutions of higher education as multi-level educational complexes nurture favourable conditions for realisation of the strategy of lifelong education. Today a technical university offering training of future engineers is facing a topic issue of creating a multilevel educational complex. Materials and Methods: this paper is put together on the basis of modern Russian and foreign scientific literature about lifelong education. The authors used theoretical methods of scientific research: systemstructural analysis, synthesis, modeling, analysis and generalisations of concepts. Results: the paper presents a model of lifelong education developed by authors for a technical university as a multilevel educational complex. It is realised through a set of principles: multi-level and continuity, integration, conformity and quality, mobility, anticipation, openness, social partnership and feedback. In accordance with the purpose, objectives and principles, the content part of the model is formed. The syllabi following the described model are run in accordance with the training levels undertaken by a technical university as a multilevel educational complex. All syllabi are based on the gradual nature of their implementation. In this regard, the authors highlight three phases: diagnostic, constructive and transformative, assessing. Discussion and Conclusions: the expected result of the created model of lifelong education development in a technical university as a multilevel educational complex is presented by a graduate trained for effective professional activity, competitive, prepared and sought-after at the regional labour market.

Multilevel Modeling of the Performance Variance

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Alexandre Teixeira Dias

2012-12-01

Full Text Available Focusing on the identification of the role played by Industry on the relations between Corporate Strategic Factors and Performance, the hierarchical multilevel modeling method was adopted when measuring and analyzing the relations between the variables that comprise each level of analysis. The adequacy of the multilevel perspective to the study of the proposed relations was identified and the relative importance analysis point out to the lower relevance of industry as a moderator of the effects of corporate strategic factors on performance, when the latter was measured by means of return on assets, and that industry don‟t moderates the relations between corporate strategic factors and Tobin‟s Q. The main conclusions of the research are that the organizations choices in terms of corporate strategy presents a considerable influence and plays a key role on the determination of performance level, but that industry should be considered when analyzing the performance variation despite its role as a moderator or not of the relations between corporate strategic factors and performance.

Athletes' perceptions of coaching competency and team conflict in sport teams: A multilevel analysis.

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González-Ponce, I; Leo, F M; Jiménez, R; Sánchez-Oliva, D; Sarmento, H; Figueiredo, A; García-Calvo, T

2018-04-23

The purpose of this study was to examine the relationship between coaching competency and team conflict, at individual and team levels, over the season. The participants were professional female and male soccer players, who participated in the First and Second Division. A longitudinal study was performed. At Time 1, the sample of participants consisted of 581 soccer players aged between 15 and 39 years. At Time 2, 549 players were recruited from the original sample aged between 15 and 37 years. Finally, at Time 3, the sample comprised 576 players aged between 15 and 37 years. All participants completed a multi-section questionnaire assessing coaching competency (motivation, game strategy, technique competency, and character-building competency) and team conflict (task conflict and relationship conflict). Results showed that both task and relationship conflict increased significantly over time. Multilevel modelling analysis showed that game strategy and character-building competencies negatively predicted both task and relationship conflicts at the individual level, whereas motivation competency was also added as a significant predictor of task conflict at the team level. Moreover, technique competency positively predicted task conflict at the team level. The current study suggests the importance of coaching competency in group dynamics in sport.

Accentuate the Positive: Positive Sentiments and Status in Task Groups

Science.gov (United States)

Bianchi, Alison J.; Lancianese, Donna A.

2007-01-01

We explore the capacity of positive sentiments, those enduring affective states one achieves when one likes another, to impact status structures. Do positive sentiments combine with existing aspects of interaction to create status hierarchies and potentially change the social order, or do they moderate the effects of extant structure by dampening…

Multilevel quadrature of elliptic PDEs with log-normal diffusion

KAUST Repository

Harbrecht, Helmut

2015-01-07

We apply multilevel quadrature methods for the moment computation of the solution of elliptic PDEs with lognormally distributed diffusion coefficients. The computation of the moments is a difficult task since they appear as high dimensional Bochner integrals over an unbounded domain. Each function evaluation corresponds to a deterministic elliptic boundary value problem which can be solved by finite elements on an appropriate level of refinement. The complexity is thus given by the number of quadrature points times the complexity for a single elliptic PDE solve. The multilevel idea is to reduce this complexity by combining quadrature methods with different accuracies with several spatial discretization levels in a sparse grid like fashion.

Pembuatan Sistem Informasi Multilevel Marketing (MLM) Berbasis Web Studi Kasus Pada PT. Mediderma Indonesia

OpenAIRE

Suhartanto, Johny; Soedjianto, Felicia; Budhi, Gregorius Satia

2005-01-01

Multilevel Marketing (MLM) is a marketing method that sells the product directly to the customers. And this method has been booming in Indonesia at this moment. MLM itself is a directly selling system through marketing program conformed more than one level, where the trading partner can get selling commission and bonus from the result of selling goods or services those did by itself and the members of network inside their own group. PT. Mediderma Indonesia is a firm which imports consumer go...

Within- and between-person and group variance in behavior and beliefs in cross-cultural longitudinal data.

Science.gov (United States)

Deater-Deckard, Kirby; Godwin, Jennifer; Lansford, Jennifer E; Bacchini, Dario; Bombi, Anna Silvia; Bornstein, Marc H; Chang, Lei; Di Giunta, Laura; Dodge, Kenneth A; Malone, Patrick S; Oburu, Paul; Pastorelli, Concetta; Skinner, Ann T; Sorbring, Emma; Steinberg, Laurence; Tapanya, Sombat; Alampay, Liane Peña; Uribe Tirado, Liliana Maria; Zelli, Arnaldo; Al-Hassan, Suha M

2018-01-01

This study grapples with what it means to be part of a cultural group, from a statistical modeling perspective. The method we present compares within- and between-cultural group variability, in behaviors in families. We demonstrate the method using a cross-cultural study of adolescent development and parenting, involving three biennial waves of longitudinal data from 1296 eight-year-olds and their parents (multiple cultures in nine countries). Family members completed surveys about parental negativity and positivity, child academic and social-emotional adjustment, and attitudes about parenting and adolescent behavior. Variance estimates were computed at the cultural group, person, and within-person level using multilevel models. Of the longitudinally consistent variance, most was within and not between cultural groups-although there was a wide range of between-group differences. This approach to quantifying cultural group variability may prove valuable when applied to quantitative studies of acculturation. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. All rights reserved.

Interactive and independent associations between the socioeconomic and objective built environment on the neighbourhood level and individual health: a systematic review of multilevel studies.

Science.gov (United States)

Schüle, Steffen Andreas; Bolte, Gabriele

2015-01-01

The research question how contextual factors of neighbourhood environments influence individual health has gained increasing attention in public health research. Both socioeconomic neighbourhood characteristics and factors of the built environment play an important role for health and health-related behaviours. However, their reciprocal relationships have not been systematically reviewed so far. This systematic review aims to identify studies applying a multilevel modelling approach which consider both neighbourhood socioeconomic position (SEP) and factors of the objective built environment simultaneously in order to disentangle their independent and interactive effects on individual health. The three databases PubMed, PsycINFO, and Web of Science were systematically searched with terms for title and abstract screening. Grey literature was not included. Observational studies from USA, Canada, Australia, New Zealand, and Western European countries were considered which analysed simultaneously factors of neighbourhood SEP and the objective built environment with a multilevel modelling approach. Adjustment for individual SEP was a further inclusion criterion. Thirty-three studies were included in qualitative synthesis. Twenty-two studies showed an independent association between characteristics of neighbourhood SEP or the built environment and individual health outcomes or health-related behaviours. Twenty-one studies found cross-level or within-level interactions either between neighbourhood SEP and the built environment, or between neighbourhood SEP or the built environment and individual characteristics, such as sex, individual SEP or ethnicity. Due to the large variation of study design and heterogeneous reporting of results the identification of consistent findings was problematic and made quantitative analysis not possible. There is a need for studies considering multiple neighbourhood dimensions and applying multilevel modelling in order to clarify their causal

A new configuration for multilevel converters with diode clamped topology

DEFF Research Database (Denmark)

Nami, A.; Zare, F.; Ledwich, G.

2008-01-01

Due to the increased use of renewable energy and power elctronic applications, more multilevel converters (MLC) are developed. A Neutral Point Clamped (NPC) inverter is one of the most used multilevel topologies for wind turbine (WT) and photovoltaic (PV) applications. One of the most crucial...... of load changes which can avoid neutral point balancing problem in such converters. In addition, the presented topology is suitable for renewable energy systems to boost the low rectified output-voltage. In order to verify the proposed topology, steady state analysis, modelling and simulations are carried...

Immigrant maternal depression and social networks. A multilevel Bayesian spatial logistic regression in South Western Sydney, Australia.

Science.gov (United States)

Eastwood, John G; Jalaludin, Bin B; Kemp, Lynn A; Phung, Hai N; Barnett, Bryanne E W

2013-09-01

The purpose is to explore the multilevel spatial distribution of depressive symptoms among migrant mothers in South Western Sydney and to identify any group level associations that could inform subsequent theory building and local public health interventions. Migrant mothers (n=7256) delivering in 2002 and 2003 were assessed at 2-3 weeks after delivery for risk factors for depressive symptoms. The binary outcome variables were Edinburgh Postnatal Depression Scale scores (EPDS) of >9 and >12. Individual level variables included were: financial income, self-reported maternal health, social support network, emotional support, practical support, baby trouble sleeping, baby demanding and baby not content. The group level variable reported here is aggregated social support networks. We used Bayesian hierarchical multilevel spatial modelling with conditional autoregression. Migrant mothers were at higher risk of having depressive symptoms if they lived in a community with predominantly Australian-born mothers and strong social capital as measured by aggregated social networks. These findings suggest that migrant mothers are socially isolated and current home visiting services should be strengthened for migrant mothers living in communities where they may have poor social networks. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Converter DC/AC Multilevel of Three Cells: Modeling and Simulation

Directory of Open Access Journals (Sweden)

Julián Peláez-Restrepo

2013-11-01

Full Text Available This paper presents a three-cell converter DC / AC. Multilevel topologies are attracting attention in the industry, obtained as a ripple on the state variables much smaller, and reduces stress on the switching devices. The topology used in this work is known in the technical literature as floating capacitor multilevel inverter, which imposes the challenge of balancing the voltage across each cell switching using floating capacitors, besides obtaining a sinusoidal signal regulated. The paper presents the averaged model of the inverter, and results obtained through simulation.

Social control of public expenditures in a multilevel principal-agent approach

Directory of Open Access Journals (Sweden)

VALDEMIR PIRES

2015-12-01

Full Text Available ABSTRACTThis study enhances the principal-agent model by incorporating a multilevel perspective and differences among agency situations. A theoretical discussion is developed using a proposed intersection of methodological focuses and a descriptive-exemplificative hypothetical analysis. The analysis is applied to public expenditure social control in representative democracies, and as a result, a principal-agent model unfolds that incorporates a decision-making perspective and focuses on formulation, negotiation, articulation, and implementation competencies. Thus, it is possible to incorporate elements into the principal-agent model to make it more permeable to individual, group, and societal idiosyncrasies with respect to public expenditure social control.

[Promoting a balanced diet and physical activity among children : Conditions for the successful implementation and maintenance of multi-level interventions and policies: Results of two qualitative case studies].

Science.gov (United States)

Steenbock, Berit; Muellmann, Saskia; Zeeb, Hajo; Pischke, Claudia R

2017-10-01

To date, conditions for successfully implementing and maintaining multi-level interventions and policies for the promotion of a balanced diet and physical activity are not well understood from the perspective of stakeholders. The aim of this article is to examine which factors are regarded as facilitating or impeding introduction, implementation and maintenance of multi-level interventions and policies from the standpoint of stakeholders. Semi-structured face-to-face interviews with stakeholders of one multi-level intervention (Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS [IDEFICS] for the prevention of childhood obesity, n = 4) and one policy (Federal state offices coordinating networks for the provision of healthy food options in schools, n = 3) were analysed using qualitative content analysis. In both cases, the use of existing structures facilitated introduction, implementation and maintenance. Additionally, training of staff for implementation according to standardised protocols or concepts and taking structures and work conditions of settings into account during implementation were considered essential. In both cases, conflicting interests in interdisciplinary stakeholder teams regarding intervention content and implementation were identified as a barrier. A lack of political support and insecure long-term funding only played a role in regard to the implementation and maintenance of policies. On the other hand, target groups of the multi-level intervention were not sufficiently involved in the development of intervention materials which resulted in a lack of tailoring and acceptance in the target groups. The results provide important insights into the long-term implementation of multi-level interventions and policies in different settings.

Use of multilevel logistic regression to identify the causes of differential item functioning.

Science.gov (United States)

Balluerka, Nekane; Gorostiaga, Arantxa; Gómez-Benito, Juana; Hidalgo, María Dolores

2010-11-01

Given that a key function of tests is to serve as evaluation instruments and for decision making in the fields of psychology and education, the possibility that some of their items may show differential behaviour is a major concern for psychometricians. In recent decades, important progress has been made as regards the efficacy of techniques designed to detect this differential item functioning (DIF). However, the findings are scant when it comes to explaining its causes. The present study addresses this problem from the perspective of multilevel analysis. Starting from a case study in the area of transcultural comparisons, multilevel logistic regression is used: 1) to identify the item characteristics associated with the presence of DIF; 2) to estimate the proportion of variation in the DIF coefficients that is explained by these characteristics; and 3) to evaluate alternative explanations of the DIF by comparing the explanatory power or fit of different sequential models. The comparison of these models confirmed one of the two alternatives (familiarity with the stimulus) and rejected the other (the topic area) as being a cause of differential functioning with respect to the compared groups.

A Multi-step and Multi-level approach for Computer Aided Molecular Design

DEFF Research Database (Denmark)

. The problem formulation step incorporates a knowledge base for the identification and setup of the design criteria. Candidate compounds are identified using a multi-level generate and test CAMD solution algorithm capable of designing molecules having a high level of molecular detail. A post solution step...... using an Integrated Computer Aided System (ICAS) for result analysis and verification is included in the methodology. Keywords: CAMD, separation processes, knowledge base, molecular design, solvent selection, substitution, group contribution, property prediction, ICAS Introduction The use of Computer...... Aided Molecular Design (CAMD) for the identification of compounds having specific physic...

Robust Algebraic Multilevel Methods and Algorithms

CERN Document Server

Kraus, Johannes

2009-01-01

This book deals with algorithms for the solution of linear systems of algebraic equations with large-scale sparse matrices, with a focus on problems that are obtained after discretization of partial differential equations using finite element methods. Provides a systematic presentation of the recent advances in robust algebraic multilevel methods. Can be used for advanced courses on the topic.

A multilevel investigation of motivational cultural intelligence, organizational diversity climate, and cultural sales: evidence from U.S. real estate firms.

Science.gov (United States)

Chen, Xiao-Ping; Liu, Dong; Portnoy, Rebecca

2012-01-01

Adopting a multilevel theoretical framework, the authors examined how motivational cultural intelligence influences individual cultural sales--the number of housing transactions occurring between people of different cultural origins. Data from 305 real estate agents employed at 26 real estate firms in the United States demonstrated that an individual's motivational cultural intelligence is positively related to his or her cultural sales. This positive relationship is enhanced by the firm's motivational cultural intelligence and diversity climate. The authors discuss the theoretical and practical implications of their findings in a workplace context that involves cross-cultural interpersonal interactions.

Finite Volume Element (FVE) discretization and multilevel solution of the axisymmetric heat equation

Science.gov (United States)

Litaker, Eric T.

1994-12-01

The axisymmetric heat equation, resulting from a point-source of heat applied to a metal block, is solved numerically; both iterative and multilevel solutions are computed in order to compare the two processes. The continuum problem is discretized in two stages: finite differences are used to discretize the time derivatives, resulting is a fully implicit backward time-stepping scheme, and the Finite Volume Element (FVE) method is used to discretize the spatial derivatives. The application of the FVE method to a problem in cylindrical coordinates is new, and results in stencils which are analyzed extensively. Several iteration schemes are considered, including both Jacobi and Gauss-Seidel; a thorough analysis of these schemes is done, using both the spectral radii of the iteration matrices and local mode analysis. Using this discretization, a Gauss-Seidel relaxation scheme is used to solve the heat equation iteratively. A multilevel solution process is then constructed, including the development of intergrid transfer and coarse grid operators. Local mode analysis is performed on the components of the amplification matrix, resulting in the two-level convergence factors for various combinations of the operators. A multilevel solution process is implemented by using multigrid V-cycles; the iterative and multilevel results are compared and discussed in detail. The computational savings resulting from the multilevel process are then discussed.

Loading Analysis of Modular Multi-level Converter for Offshore High-voltage DC Application under Various Grid Faults

DEFF Research Database (Denmark)

Liu, Hui; Ma, Ke; Loh, Poh Chiang

2016-01-01

challenges but may also result in overstressed components for the modular multi-level converter. However, the thermal loading of the modular multi-level converter under various grid faults has not yet been clarified. In this article, the power loss and thermal performance of the modular multi-level converter...... low-voltage ride-through strongly depend on the types and severity values of grid voltage dips. The thermal distribution among the three phases of the modular multi-level converter may be quite uneven, and some devices are much more stressed than the normal operating condition, which may...

Behavioral spillovers from freeriding in multilevel interactions.

NARCIS (Netherlands)

Thommes, K; Vyrastekova, J.; Akkerman, A.

2015-01-01

We study multilevel interactions using experimental methods. Does the efficiency of a production team suffer from the freeriding behavior of some team members at the firm level? Can we identify behavioral spillovers affecting teams? We isolate common tasks that teams must complete - coordination and

The relationship between multilevel models and non-parametric multilevel mixture models: Discrete approximation of intraclass correlation, random coefficient distributions, and residual heteroscedasticity.

Science.gov (United States)

Rights, Jason D; Sterba, Sonya K

2016-11-01

Multilevel data structures are common in the social sciences. Often, such nested data are analysed with multilevel models (MLMs) in which heterogeneity between clusters is modelled by continuously distributed random intercepts and/or slopes. Alternatively, the non-parametric multilevel regression mixture model (NPMM) can accommodate the same nested data structures through discrete latent class variation. The purpose of this article is to delineate analytic relationships between NPMM and MLM parameters that are useful for understanding the indirect interpretation of the NPMM as a non-parametric approximation of the MLM, with relaxed distributional assumptions. We define how seven standard and non-standard MLM specifications can be indirectly approximated by particular NPMM specifications. We provide formulas showing how the NPMM can serve as an approximation of the MLM in terms of intraclass correlation, random coefficient means and (co)variances, heteroscedasticity of residuals at level 1, and heteroscedasticity of residuals at level 2. Further, we discuss how these relationships can be useful in practice. The specific relationships are illustrated with simulated graphical demonstrations, and direct and indirect interpretations of NPMM classes are contrasted. We provide an R function to aid in implementing and visualizing an indirect interpretation of NPMM classes. An empirical example is presented and future directions are discussed. © 2016 The British Psychological Society.

Multilevel groundwater monitoring of hydraulic head and temperature in the eastern Snake River Plain aquifer, Idaho National Laboratory, Idaho, 2009–10

Science.gov (United States)

Twining, Brian V.; Fisher, Jason C.

2012-01-01

provide evidence for stratification and mixing of water types along the southern boundary of the Idaho National Laboratory. Vertical head and temperature change were quantified for each of the nine multilevel monitoring systems. The vertical head gradients were defined for the major inflections in the head profiles and were as high as 2.1 feet per foot. Low vertical head gradients indicated potential vertical connectivity and flow, and large gradient inflections indicated zones of relatively low vertical connectivity. Generally, zones that primarily are composed of fractured basalt displayed relatively small vertical head differences. Large head differences were attributed to poor vertical connectivity between fracture units because of sediment layering and/or dense basalt. Groundwater temperatures in all boreholes ranged from 10.2 to 16.3˚C. Normalized mean hydraulic head values were analyzed for all nine multilevel monitoring wells for the period of record (2007-10). The mean head values suggest a moderately positive correlation among all boreholes, which reflects regional fluctuations in water levels in response to seasonality. However, the temporal trend is slightly different when the location is considered; wells located along the southern boundary, within the axial volcanic high, show a strongly positive correlation.

A multi-level qualitative analysis of Telehomecare in Ontario: challenges and opportunities.

Science.gov (United States)

Hunting, Gemma; Shahid, Nida; Sahakyan, Yeva; Fan, Iris; Moneypenny, Crystal R; Stanimirovic, Aleksandra; North, Taylor; Petrosyan, Yelena; Krahn, Murray D; Rac, Valeria E

2015-12-09

Despite research demonstrating the potential effectiveness of Telehomecare for people with Chronic Obstructive Pulmonary Disease and Heart Failure, broad-scale comprehensive evaluations are lacking. This article discusses the qualitative component of a mixed-method program evaluation of Telehomecare in Ontario, Canada. The objective of the qualitative component was to explore the multi-level factors and processes which facilitate or impede the implementation and adoption of the program across three regions where it was first implemented. The study employs a multi-level framework as a conceptual guide to explore the facilitators and barriers to Telehomecare implementation and adoption across five levels: technology, patients, providers, organizations, and structures. In-depth semi-structured interviews and ethnographic observations with program stakeholders, as well as a Telehomecare document review were used to elicit key themes. Study participants (n = 89) included patients and/or informal caregivers (n = 39), health care providers (n = 23), technicians (n = 2), administrators (n = 12), and decision makers (n = 13) across three different Local Health Integration Networks in Ontario. Key facilitators to Telehomecare implementation and adoption at each level of the multi-level framework included: user-friendliness of Telehomecare technology, patient motivation to participate in the program, support for Telehomecare providers, the integration of Telehomecare into broader health service provision, and comprehensive program evaluation. Key barriers included: access-related issues to using the technology, patient language (if not English or French), Telehomecare provider time limitations, gaps in health care provision for patients, and structural barriers to patient participation related to geography and social location. Though Telehomecare has the potential to positively impact patient lives and strengthen models of health care provision, a

New Approaches to Circulating Current Controllers for Modular Multilevel Converters

Directory of Open Access Journals (Sweden)

Miguel Moranchel

2017-01-01

Full Text Available In the next years, modular multilevel converters (MMCs are going to be a next generation multilevel converters for medium to high voltage conversion applications, such as medium voltage motor drives, medium voltage flexible AC transmission systems (FACTS and high voltage direct current transmission. They provide advantages such as high modularity, availability, low generation of harmonics, etc. However, the circulating current distorts the leg currents and increases the rated current of power devices, which further increases system cost. This paper focuses on analysis and suppression of these currents in a MMC using two algorithms for tracking of harmonics. For this work resonant controllers and repetitive controllers have been selected. Both controllers are analyzed and simulations results are presented. Moreover, the controllers have been tested and validated for a three phase MMC operating as an inverter using a real processing platform based on Zynq by Xilinx and designed to control large multilevel converters and in a real MMC prototype. These results are provided to demonstrate the feasibility of the proposed method.

Multi-level barriers to LTBI treatment: a research note.

Science.gov (United States)

Hill, Linda; Blumberg, Elaine; Sipan, Carol; Schmitz, Katharine; West, Joshua; Kelley, Norma; Hovell, Melbourne

2010-08-01

This study describes the barriers to effective and timely LTBI treatment encountered in a research study on INH adherence in Latino adolescents. Participant study logs were reviewed, results of continuing medical education pretests for medical providers were examined, and participating medical facilities were contacted in order to construct a profile of multi-level barriers to LTBI treatment. A total of 285 TST positive Latino (96%) high school students were recruited into the trial. We encountered a lack of understanding of the gravity of tuberculosis infection among both the public and providers of health care. Parents and adolescents cited competing priorities, transportation problems and financial constraints as reasons for non-compliance. Improved education of the public and physicians is needed regarding the gravity of the disease and the value of treatment, as well as public and financial support for LTBI treatment by both the government and the medical community.

[The Positionality of Caring Action: Small Group Dialogue in a Course on Nursing Ethics].

Science.gov (United States)

Chiang, Hsien-Hsien

2016-12-01

The content of nursing-ethics education has typically focused on the external standards of caring behavior and neglected the relationship between the ethical attitudes and internal experiences of caregivers. To explore the embodied experience in order to define the positionality of caring action, which is necessary to enrich the content of nursing ethics through small-group-learning-based dialogue. The researcher, as a participant observer, teaches a course on nursing ethics. Reflective analysis was used to analyze the data from the process of small group learning, a reflective group of faculty members, and 30 reflective journals submitted by 10 students. The results identified three items that were related to the positionality of caring action: the attitudes of belief, including the choice to belief and deep understanding; articulating the value system, including exploring affectivity and positionality; and cultivating the self through self-dialogues and dialogues with others. The attitudes of belief promote trust in interpersonal relationships. Articulating the value system deepens the meaning of caring. Cultivating the self may facilitate the ethical self.

The essential tension competition, cooperation and multilevel selection in evolution

CERN Document Server

Bahar, Sonya

2018-01-01

'The Essential Tension' explores how agents that naturally compete come to act together as a group. The author argues that the controversial concept of multilevel selection is essential to biological evolution, a proposition set to stimulate new debate. The idea of one collective unit emerging from the cooperative interactions of its constituent (and mutually competitive) parts has its roots in the ancient world. More recently, it has illuminated studies of animal behavior, and played a controversial role in evolutionary biology. In Part I, the author explores the historical development of the idea of a collectivity in biological systems, from early speculations on the sociology of human crowd behavior, through the mid-twentieth century debates over the role of group selection in evolution, to the notion of the selfish gene. Part II investigates the balance between competition and cooperation in a range of contemporary biological problems, from flocking and swarming to experimental evolution and the evolutio...

[Discarthrosis with hyperalgic lumbar multileveled radicular syndrome].

Science.gov (United States)

Sardaru, D; Tiţu, Gabriela; Pendefunda, L

2012-01-01

The problems at the level of intervertebral discs are producing dysfunctions and important functional regression at the level of lumbar column, at a stage at which the patient could remain blocked in an anterior or lateral flexion position or producing an antalgic position of scoliosis that could incapacitate the patient to perform activities of daily living. The medical rehabilitation, in such cases, must seek not only the relief of local pain through different methods of obtaining it, but also the functional reeducation of the intervertebral articulations through specific analytical mobilization in order to achieve the biomechanical harmonization of the rachis. We report the case study of a 66 year-old patient who presented to our clinic for medical consult and physical therapy when he was diagnosed with discharthrosis, hyperalgic lumbar multileveled radiculopathy at L4-L5 and L5-S1. The lumbar x-ray showed osteophytes, disc narrowing at the level of L5-S1 and inter-apophysis arthrosis. The clinical examination revealed difficulty walking with pain in the right sacroiliac articulations and right sciatic emergence with plantar paraesthesia. The patient developed pain induced scoliosis on the right side that restricted the lumbar range of motion and prevented the right flexion blocking him into an left flexion, any attempt of straightening inducing pain. The condition was treated using specific analytical lumbar mobilization for the realignment of the vertebrae complex. In this case study, we found that functional reeducation in cases of pain induced deviations of the rachis of the column should be centered on the harmonization of inadequate pressure and position of the complex intervertebral articulations.

Job demands, burnout, and engagement among nurses: A multi-level analysis of ORCAB data investigating the moderating effect of teamwork

OpenAIRE

Montgomery, Anthony; Sp?nu, Florina; B?ban, Adriana; Panagopoulou, Efharis

2015-01-01

According to the Job Demands-Resources (JD-R) model, burnout and engagement are psychological reactions that develop when individual characteristics interact with work characteristics. This study tests the JD-R model using multilevel analysis to test the main and moderating effects of teamwork effectiveness among 1156 nurses in 93 departments from seven European countries. Workload, emotional and organizational demands were positively associated with emotional exhaustion, depersonalization, a...

Multi-Level Security Cannot Realise NEC Objectives

NARCIS (Netherlands)

Schotanus, H.A.; Hartog, T.; Verkoelen, C.A.A.

2012-01-01

Multi-Level Security (MLS) is often viewed as the holy grail of information security, especially in those environments where information of different classifications is being processed. In this paper we argue that MLS cannot facilitate the right balance between need-to-protect and duty-to-share as

First 3D Cadastral Registration of Multi-level Ownerships Rights in the Netherlands

NARCIS (Netherlands)

Ploeger, H.D.; Stoter, J.E.; Roes, R; Van der Riet, E.; Biljecki, F.; Ledoux, H.

2016-01-01

This paper reports on the first 3D cadastral registration of multi-level ownerships rights in the Netherlands, which was accomplished in March 2016. It is the result of a study that was undertaken from 2013 to 2015 to determine how insight about multi-level ownership can be provided in 3D by the

A water treatment case study for quantifying model performance with multilevel flow modeling

Directory of Open Access Journals (Sweden)

Emil K. Nielsen

2018-05-01

Full Text Available Decision support systems are a key focus of research on developing control rooms to aid operators in making reliable decisions and reducing incidents caused by human errors. For this purpose, models of complex systems can be developed to diagnose causes or consequences for specific alarms. Models applied in safety systems of complex and safety-critical systems require rigorous and reliable model building and testing. Multilevel flow modeling is a qualitative and discrete method for diagnosing faults and has previously only been validated by subjective and qualitative means. To ensure reliability during operation, this work aims to synthesize a procedure to measure model performance according to diagnostic requirements. A simple procedure is proposed for validating and evaluating the concept of multilevel flow modeling. For this purpose, expert statements, dynamic process simulations, and pilot plant experiments are used for validation of simple multilevel flow modeling models of a hydrocyclone unit for oil removal from produced water. Keywords: Fault Diagnosis, Model Validation, Multilevel Flow Modeling, Produced Water Treatment

A multilevel analysis of long-term psychological distress among Belarusians affected by the Chernobyl disaster.

Science.gov (United States)

Beehler, G P; Baker, J A; Falkner, K; Chegerova, T; Pryshchepava, A; Chegerov, V; Zevon, M; Bromet, E; Havenaar, J; Valdismarsdottir, H; Moysich, K B

2008-11-01

Radiation contamination and sociopolitical instability following the Chernobyl nuclear power plant disaster have had a profound impact on Belarus. To investigate the factors that impact long-term mental health outcomes of this population almost 20 years after the disaster. Cross-sectional study. In-person interviews were conducted with 381 men and women from two geographic areas of differing radiation contamination within Belarus. Participants completed surveys of demographics, psychosocial factors and psychological distress. Individual-level characteristics were combined with household-level measures of radiation contamination exposure and family characteristics to create multilevel predictive models of psychological distress. Between-household effects accounted for 20% of variability in depression and anxiety scores, but only 8% of variability in somatization scores. Degree of chronic daily stressors showed a significant positive relationship with psychological distress, whereas mastery/controllability showed a significant inverse relationship with distress. At household level, perceived family problems, but not level of residential radiation contamination, was the best predictor of distress. Multilevel modelling indicates that long-term psychological distress among Belarusians affected by the Chernobyl disaster is better predicted by stress-moderating psychosocial factors present in one's daily life than by level of residential radiation contamination.

Quantification of mold contamination in multi-level buildings using the Environmental Relative Moldiness Index

Science.gov (United States)

The goal of this study was to evaluate the possible use of the Environmental Relative Moldiness Index (ERMI) to quantify mold contamination in multi-level, office buildings. Settled-dust samples were collected in multi-level, office buildings and the ERMI value for each sample de...

Experiments of Multi-Level Read-Only Recording Using Readout Signal Wave-Shape Modulation

International Nuclear Information System (INIS)

Yi, Tang; Jing, Pei; Long-Fa, Pan; Yi, Ni; Hua, Hu; Bu-Qing, Zhang

2008-01-01

An innovative multilevel read-only recording method is proposed. In this method, a short pit/land is deliberately inserted to the original land/pit. This modifies the wave-shape of readout signal. Taking the wave-shape as the symbol of level detection, a signal wave-shape modulation (SWSM) multilevel method is realized. This method is carried out and validated on the DVD read-only manufacture and readout system. A capacity of 15 GB can be expected, and a bit error rate of 10 −4 is achieved. The capacity can meet the demand of high definition movie publication. This method also provides a potential multi-level solution for other storage formats and systems. (fundamental areas of phenomenology (including applications))

Linking Narcissism, Motivation, and Doping Attitudes in Sport: A Multilevel Investigation Involving Coaches and Athletes.

Science.gov (United States)

Matosic, Doris; Ntoumanis, Nikos; Boardley, Ian David; Stenling, Andreas; Sedikides, Constantine

2016-12-01

Research on coaching (Bartholomew, Ntoumanis, & Thøgersen-Ntoumani, 2009) has shown that coaches can display controlling behaviors that have detrimental effects on athletes' basic psychological needs and quality of sport experiences. The current study extends this literature by considering coach narcissism as a potential antecedent of coaches' controlling behaviors. Further, the study tests a model linking coaches' (n = 59) own reports of narcissistic tendencies with athletes' (n = 493) perceptions of coach controlling behaviors, experiences of need frustration, and attitudes toward doping. Multilevel path analysis revealed that coach narcissism was directly and positively associated with athletes' perceptions of controlling behaviors and was indirectly and positively associated with athletes' reports of needs frustration. In addition, athletes' perceptions of coach behaviors were positively associated-directly and indirectly-with attitudes toward doping. The findings advance understanding of controlling coach behaviors, their potential antecedents, and their associations with athletes' attitudes toward doping.

A Goal Programming Model for the Siting of Multilevel EMS Systems.

Science.gov (United States)

1980-03-01

Management," unpublished Ph.D. thesis, University of Texas, Austin, Texas, 1971. -23- (11) Daskin , M. and E. Stern, " A Multiobjective Set Covering...GOAL PROGRAM4MING MODEL FOR THE SITING OF MULTILEVEL EMS SYSTE-ETC(U) UNM1AR 80 A CHARNES, J E STORBECK N000iA-75-C-569 WICLASSIFIED CCS-366 N...366 A GOAL PROGRAMMING MODEL FOR THE SITING OF MULTILEVEL EMS SYSTEMS by A . Charnes J. Storbeck March 1980 This project was partially supported by

Individual relocation decisions after tornadoes: a multi-level analysis.

Science.gov (United States)

Cong, Zhen; Nejat, Ali; Liang, Daan; Pei, Yaolin; Javid, Roxana J

2018-04-01

This study examines how multi-level factors affected individuals' relocation decisions after EF4 and EF5 (Enhanced Fujita Tornado Intensity Scale) tornadoes struck the United States in 2013. A telephone survey was conducted with 536 respondents, including oversampled older adults, one year after these two disaster events. Respondents' addresses were used to associate individual information with block group-level variables recorded by the American Community Survey. Logistic regression revealed that residential damage and homeownership are important predictors of relocation. There was also significant interaction between these two variables, indicating less difference between homeowners and renters at higher damage levels. Homeownership diminished the likelihood of relocation among younger respondents. Random effects logistic regression found that the percentage of homeownership and of higher income households in the community buffered the effect of damage on relocation; the percentage of older adults reduced the likelihood of this group relocating. The findings are assessed from the standpoint of age difference, policy implications, and social capital and vulnerability. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.

Multilevel inverter switching controller using a field programmable ...

African Journals Online (AJOL)

Conducted simulation and measurement results verified and validated the switching controller design functionality and requirement. Keywords: multilevel inverter, switching controller; FPGA, general purpose processor (GPP);digital signal processing (DSP); IGBT; Verilog, power consumption; harmonic elimination (SHE).

Multi-level restricted maximum likelihood covariance estimation and kriging for large non-gridded spatial datasets

KAUST Repository

Castrillon, Julio; Genton, Marc G.; Yokota, Rio

2015-01-01

We develop a multi-level restricted Gaussian maximum likelihood method for estimating the covariance function parameters and computing the best unbiased predictor. Our approach produces a new set of multi-level contrasts where the deterministic

What it takes to get proactive: An integrative multilevel model of the antecedents of personal initiative.

Science.gov (United States)

Hong, Ying; Liao, Hui; Raub, Steffen; Han, Joo Hun

2016-05-01

Building upon and extending Parker, Bindl, and Strauss's (2010) theory of proactive motivation, we develop an integrated, multilevel model to examine how contextual factors shape employees' proactive motivational states and, through these proactive motivational states, influence their personal initiative behavior. Using data from a sample of hotels collected from 3 sources and over 2 time periods, we show that establishment-level initiative-enhancing human resource management (HRM) systems were positively related to departmental initiative climate, which was positively related to employee personal initiative through employee role-breadth self-efficacy. Further, department-level empowering leadership was positively related to initiative climate only when initiative-enhancing HRM systems were low. These findings offer interesting implications for research on personal initiative and for the management of employee proactivity in organizations. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Fractal multi-level organisation of human groups in a virtual world

Science.gov (United States)

Fuchs, Benedikt; Sornette, Didier; Thurner, Stefan

2014-10-01

Humans are fundamentally social. They form societies which consist of hierarchically layered nested groups of various quality, size, and structure. The anthropologic literature has classified these groups as support cliques, sympathy groups, bands, cognitive groups, tribes, linguistic groups, and so on. Anthropologic data show that, on average, each group consists of approximately three subgroups. However, a general understanding of the structural dependence of groups at different layers is largely missing. We extend these early findings to a very large high-precision large-scale internet-based social network data. We analyse the organisational structure of a complete, multi-relational, large social multiplex network of a human society consisting of about 400,000 odd players of an open-ended massive multiplayer online game for which we know all about their various group memberships at different layers. Remarkably, the online players' society exhibits the same type of structured hierarchical layers as found in hunter-gatherer societies. Our findings suggest that the hierarchical organisation of human society is deeply nested in human psychology.

Adaptive evolution of the spike gene of SARS coronavirus: changes in positively selected sites in different epidemic groups

Directory of Open Access Journals (Sweden)

He Shao-Heng

2006-10-01

Full Text Available Abstract Background It is believed that animal-to-human transmission of severe acute respiratory syndrome (SARS coronavirus (CoV is the cause of the SARS outbreak worldwide. The spike (S protein is one of the best characterized proteins of SARS-CoV, which plays a key role in SARS-CoV overcoming species barrier and accomplishing interspecies transmission from animals to humans, suggesting that it may be the major target of selective pressure. However, the process of adaptive evolution of S protein and the exact positively selected sites associated with this process remain unknown. Results By investigating the adaptive evolution of S protein, we identified twelve amino acid sites (75, 239, 244, 311, 479, 609, 613, 743, 765, 778, 1148, and 1163 in the S protein under positive selective pressure. Based on phylogenetic tree and epidemiological investigation, SARS outbreak was divided into three epidemic groups: 02–04 interspecies, 03-early-mid, and 03-late epidemic groups in the present study. Positive selection was detected in the first two groups, which represent the course of SARS-CoV interspecies transmission and of viral adaptation to human host, respectively. In contrast, purifying selection was detected in 03-late group. These indicate that S protein experiences variable positive selective pressures before reaching stabilization. A total of 25 sites in 02–04 interspecies epidemic group and 16 sites in 03-early-mid epidemic group were identified under positive selection. The identified sites were different between these two groups except for site 239, which suggests that positively selected sites are changeable between groups. Moreover, it was showed that a larger proportion (24% of positively selected sites was located in receptor-binding domain (RBD than in heptad repeat (HR1-HR2 region in 02–04 interspecies epidemic group (p = 0.0208, and a greater percentage (25% of these sites occurred in HR1–HR2 region than in RBD in 03-early

A Multilevel Shape Fit Analysis of Neutron Transmission Data

Science.gov (United States)

Naguib, K.; Sallam, O. H.; Adib, M.; Ashry, A.

A multilevel shape fit analysis of neutron transmission data is presented. A multilevel computer code SHAPE is used to analyse clean transmission data obtained from time-of-flight (TOF) measurements. The shape analysis deduces the parameters of the observed resonances in the energy region considered in the measurements. The shape code is based upon a least square fit of a multilevel Briet-Wigner formula and includes both instrumental resolution and Doppler broadenings. Operating the SHAPE code on a test example of a measured transmission data of 151Eu, 153Eu and natural Eu in the energy range 0.025-1 eV accquired a good result for the used technique of analysis.Translated AbstractAnalyse von Neutronentransmissionsdaten mittels einer VielniveauformanpassungNeutronentransmissionsdaten werden in einer Vielniveauformanpassung analysiert. Dazu werden bereinigte Daten aus Flugzeitmessungen mit dem Rechnerprogramm SHAPE bearbeitet. Man erhält die Parameter der beobachteten Resonanzen im gemessenen Energiebereich. Die Formanpassung benutzt eine Briet-Wignerformel und berücksichtigt Linienverbreiterungen infolge sowohl der Meßeinrichtung als auch des Dopplereffekts. Als praktisches Beispiel werden 151Eu, 153Eu und natürliches Eu im Energiebereich 0.025 bis 1 eV mit guter Übereinstimmung theoretischer und experimenteller Werte behandelt.

Multi-stage decoding for multi-level block modulation codes

Science.gov (United States)

Lin, Shu

1991-01-01

In this paper, we investigate various types of multi-stage decoding for multi-level block modulation codes, in which the decoding of a component code at each stage can be either soft-decision or hard-decision, maximum likelihood or bounded-distance. Error performance of codes is analyzed for a memoryless additive channel based on various types of multi-stage decoding, and upper bounds on the probability of an incorrect decoding are derived. Based on our study and computation results, we find that, if component codes of a multi-level modulation code and types of decoding at various stages are chosen properly, high spectral efficiency and large coding gain can be achieved with reduced decoding complexity. In particular, we find that the difference in performance between the suboptimum multi-stage soft-decision maximum likelihood decoding of a modulation code and the single-stage optimum decoding of the overall code is very small: only a fraction of dB loss in SNR at the probability of an incorrect decoding for a block of 10(exp -6). Multi-stage decoding of multi-level modulation codes really offers a way to achieve the best of three worlds, bandwidth efficiency, coding gain, and decoding complexity.

Detecting bots using multi-level traffic analysis

DEFF Research Database (Denmark)

Stevanovic, Matija; Pedersen, Jens Myrup

2016-01-01

introduces a novel multi-level botnet detection approach that performs network traffic analysis of three protocols widely considered as the main carriers of botnet Command and Control (C&C) and attack traffic, i.e. TCP, UDP and DNS. The proposed method relies on supervised machine learning for identifying...

Pore-scale uncertainty quantification with multilevel Monte Carlo

KAUST Repository

Icardi, Matteo; Hoel, Haakon; Long, Quan; Tempone, Raul

2014-01-01

. Since there are no generic ways to parametrize the randomness in the porescale structures, Monte Carlo techniques are the most accessible to compute statistics. We propose a multilevel Monte Carlo (MLMC) technique to reduce the computational cost

Income inequality is associated with adolescent fertility in Brazil: a longitudinal multilevel analysis of 5,565 municipalities.

Science.gov (United States)

Chiavegatto Filho, Alexandre D P; Kawachi, Ichiro

2015-02-07

Brazil has one of the highest adolescent fertility rates in the world. Income inequality has been frequently linked to overall adolescent health, but studies that analyzed its association with adolescent fertility have been performed only in developed countries. Brazil, in the past decade, has presented a rare combination of increasing per capita income and decreasing income inequality, which could influence future desirable pathways for other countries. We analyzed every live birth from 2000 and from 2010 in each of the 5,565 municipalities of Brazil, a total of 6,049,864 births, which included 1,247,145 (20.6%) births from women aged 15 to 19. Income inequality was assessed by the Gini Coefficient and adolescent fertility by the ratio between the number of live births from women aged 15 to 19 and the number of women aged 15 to 19, calculated for each municipality. We first applied multilevel models separately for 2000 and 2010 to test the cross-sectional association between income inequality and adolescent fertility. We then fitted longitudinal first-differences multilevel models to control for time-invariant effects. We also performed a sensitivity analysis to include only municipality with satisfactory birth record coverage. Our results indicate a consistent and positive association between income inequality and adolescent fertility. After controlling for per capita income, college access, youth homicide rate and adult fertility, higher income inequality was significantly associated with higher adolescent fertility for both 2000 and 2010. The longitudinal multilevel models found similar results. The sensitivity analysis indicated that the results for the association between income inequality and adolescent fertility were robust. Adult fertility was also significantly associated with adolescent fertility in the cross-sectional and longitudinal models. Income inequality is expected to be a leading concern for most countries in the near future. Our results suggest

A multilevel simultaneous equations model for within-cluster dynamic effects, with an application to reciprocal parent-child and sibling effects.

Science.gov (United States)

Steele, Fiona; Rasbash, Jon; Jenkins, Jennifer

2013-03-01

There has been substantial interest in the social and health sciences in the reciprocal causal influences that people in close relationships have on one another. Most research has considered reciprocal processes involving only 2 units, although many social relationships of interest occur within a larger group (e.g., families, work groups, peer groups, classrooms). This article presents a general longitudinal multilevel modeling framework for the simultaneous estimation of reciprocal relationships among individuals with unique roles operating in a social group. We use family data for illustrative purposes, but the model is generalizable to any social group in which measurements of individuals in the social group occur over time, individuals have unique roles, and clustering of the data is evident. We allow for the possibility that the outcomes of family members are influenced by a common set of unmeasured family characteristics. The multilevel model we propose allows for residual variation in the outcomes of parents and children at the occasion, individual, and family levels and residual correlation between parents and children due to the unmeasured shared environment, genetic factors, and shared measurement. Another advantage of this method over approaches used in previous family research is it can handle mixed family sizes. The method is illustrated in an analysis of maternal depression and child delinquency using data from the Avon Brothers and Sisters Study. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Bayesian Optimal Experimental Design Using Multilevel Monte Carlo

KAUST Repository

Ben Issaid, Chaouki

2015-01-01

informative data about the model parameters. One of the major difficulties in evaluating the expected information gain is that it naturally involves nested integration over a possibly high dimensional domain. We use the Multilevel Monte Carlo (MLMC) method

Multidimensional radiative transfer with multilevel atoms. II. The non-linear multigrid method.

Science.gov (United States)

Fabiani Bendicho, P.; Trujillo Bueno, J.; Auer, L.

1997-08-01

A new iterative method for solving non-LTE multilevel radiative transfer (RT) problems in 1D, 2D or 3D geometries is presented. The scheme obtains the self-consistent solution of the kinetic and RT equations at the cost of only a few (iteration (Brandt, 1977, Math. Comp. 31, 333; Hackbush, 1985, Multi-Grid Methods and Applications, springer-Verlag, Berlin), an efficient multilevel RT scheme based on Gauss-Seidel iterations (cf. Trujillo Bueno & Fabiani Bendicho, 1995ApJ...455..646T), and accurate short-characteristics formal solution techniques. By combining a valid stopping criterion with a nested-grid strategy a converged solution with the desired true error is automatically guaranteed. Contrary to the current operator splitting methods the very high convergence speed of the new RT method does not deteriorate when the grid spatial resolution is increased. With this non-linear multigrid method non-LTE problems discretized on N grid points are solved in O(N) operations. The nested multigrid RT method presented here is, thus, particularly attractive in complicated multilevel transfer problems where small grid-sizes are required. The properties of the method are analyzed both analytically and with illustrative multilevel calculations for Ca II in 1D and 2D schematic model atmospheres.

Multilevel Models for the Analysis of Angle-Specific Torque Curves with Application to Master Athletes

Directory of Open Access Journals (Sweden)

Carvalho Humberto M.

2015-12-01

Full Text Available The aim of this paper was to outline a multilevel modeling approach to fit individual angle-specific torque curves describing concentric knee extension and flexion isokinetic muscular actions in Master athletes. The potential of the analytical approach to examine between individual differences across the angle-specific torque curves was illustrated including between-individuals variation due to gender differences at a higher level. Torques in concentric muscular actions of knee extension and knee extension at 60°·s-1 were considered within a range of motion between 5°and 85° (only torques “truly” isokinetic. Multilevel time series models with autoregressive covariance structures with standard multilevel models were superior fits compared with standard multilevel models for repeated measures to fit anglespecific torque curves. Third and fourth order polynomial models were the best fits to describe angle-specific torque curves of isokinetic knee flexion and extension concentric actions, respectively. The fixed exponents allow interpretations for initial acceleration, the angle at peak torque and the decrement of torque after peak torque. Also, the multilevel models were flexible to illustrate the influence of gender differences on the shape of torque throughout the range of motion and in the shape of the curves. The presented multilevel regression models may afford a general framework to examine angle-specific moment curves by isokinetic dynamometry, and add to the understanding mechanisms of strength development, particularly the force-length relationship, both related to performance and injury prevention.

Fast multilevel radiative transfer

Science.gov (United States)

Paletou, Frédéric; Léger, Ludovick

2007-01-01

The vast majority of recent advances in the field of numerical radiative transfer relies on approximate operator methods better known in astrophysics as Accelerated Lambda-Iteration (ALI). A superior class of iterative schemes, in term of rates of convergence, such as Gauss-Seidel and Successive Overrelaxation methods were therefore quite naturally introduced in the field of radiative transfer by Trujillo Bueno & Fabiani Bendicho (1995); it was thoroughly described for the non-LTE two-level atom case. We describe hereafter in details how such methods can be generalized when dealing with non-LTE unpolarised radiation transfer with multilevel atomic models, in monodimensional geometry.

Multi-level restricted maximum likelihood covariance estimation and kriging for large non-gridded spatial datasets

KAUST Repository

Castrillon, Julio

2015-11-10

We develop a multi-level restricted Gaussian maximum likelihood method for estimating the covariance function parameters and computing the best unbiased predictor. Our approach produces a new set of multi-level contrasts where the deterministic parameters of the model are filtered out thus enabling the estimation of the covariance parameters to be decoupled from the deterministic component. Moreover, the multi-level covariance matrix of the contrasts exhibit fast decay that is dependent on the smoothness of the covariance function. Due to the fast decay of the multi-level covariance matrix coefficients only a small set is computed with a level dependent criterion. We demonstrate our approach on problems of up to 512,000 observations with a Matérn covariance function and highly irregular placements of the observations. In addition, these problems are numerically unstable and hard to solve with traditional methods.

Estimating trajectories of energy intake through childhood and adolescence using linear-spline multilevel models.

Science.gov (United States)

Anderson, Emma L; Tilling, Kate; Fraser, Abigail; Macdonald-Wallis, Corrie; Emmett, Pauline; Cribb, Victoria; Northstone, Kate; Lawlor, Debbie A; Howe, Laura D

2013-07-01

Methods for the assessment of changes in dietary intake across the life course are underdeveloped. We demonstrate the use of linear-spline multilevel models to summarize energy-intake trajectories through childhood and adolescence and their application as exposures, outcomes, or mediators. The Avon Longitudinal Study of Parents and Children assessed children's dietary intake several times between ages 3 and 13 years, using both food frequency questionnaires (FFQs) and 3-day food diaries. We estimated energy-intake trajectories for 12,032 children using linear-spline multilevel models. We then assessed the associations of these trajectories with maternal body mass index (BMI), and later offspring BMI, and also their role in mediating the relation between maternal and offspring BMIs. Models estimated average and individual energy intake at 3 years, and linear changes in energy intake from age 3 to 7 years and from age 7 to 13 years. By including the exposure (in this example, maternal BMI) in the multilevel model, we were able to estimate the average energy-intake trajectories across levels of the exposure. When energy-intake trajectories are the exposure for a later outcome (in this case offspring BMI) or a mediator (between maternal and offspring BMI), results were similar, whether using a two-step process (exporting individual-level intercepts and slopes from multilevel models and using these in linear regression/path analysis), or a single-step process (multivariate multilevel models). Trajectories were similar when FFQs and food diaries were assessed either separately, or when combined into one model. Linear-spline multilevel models provide useful summaries of trajectories of dietary intake that can be used as an exposure, outcome, or mediator.

A single-phase multi-level D-STATCOM inverter using modular multi-level converter (MMC) topology for renewable energy sources

Science.gov (United States)

Sotoodeh, Pedram

This dissertation presents the design of a novel multi-level inverter with FACTS capability for small to mid-size (10-20kW) permanent-magnet wind installations using modular multi-level converter (MMC) topology. The aim of the work is to design a new type of inverter with D-STATCOM option to provide utilities with more control on active and reactive power transfer of distribution lines. The inverter is placed between the renewable energy source, specifically a wind turbine, and the distribution grid in order to fix the power factor of the grid at a target value, regardless of wind speed, by regulating active and reactive power required by the grid. The inverter is capable of controlling active and reactive power by controlling the phase angle and modulation index, respectively. The unique contribution of the proposed work is to combine the two concepts of inverter and D-STATCOM using a novel voltage source converter (VSC) multi-level topology in a single unit without additional cost. Simulations of the proposed inverter, with 5 and 11 levels, have been conducted in MATLAB/Simulink for two systems including 20 kW/kVAR and 250 W/VAR. To validate the simulation results, a scaled version (250 kW/kVAR) of the proposed inverter with 5 and 11 levels has been built and tested in the laboratory. Experimental results show that the reduced-scale 5- and 11-level inverter is able to fix PF of the grid as well as being compatible with IEEE standards. Furthermore, total cost of the prototype models, which is one of the major objectives of this research, is comparable with market prices.

Feasibility study of current pulse induced 2-bit/4-state multilevel programming in phase-change memory

Science.gov (United States)

Liu, Yan; Fan, Xi; Chen, Houpeng; Wang, Yueqing; Liu, Bo; Song, Zhitang; Feng, Songlin

2017-08-01

In this brief, multilevel data storage for phase-change memory (PCM) has attracted more attention in the memory market to implement high capacity memory system and reduce cost-per-bit. In this work, we present a universal programing method of SET stair-case current pulse in PCM cells, which can exploit the optimum programing scheme to achieve 2-bit/ 4state resistance-level with equal logarithm interval. SET stair-case waveform can be optimized by TCAD real time simulation to realize multilevel data storage efficiently in an arbitrary phase change material. Experimental results from 1 k-bit PCM test-chip have validated the proposed multilevel programing scheme. This multilevel programming scheme has improved the information storage density, robustness of resistance-level, energy efficient and avoiding process complexity.

Double-Group Particle Swarm Optimization and Its Application in Remote Sensing Image Segmentation.

Science.gov (United States)

Shen, Liang; Huang, Xiaotao; Fan, Chongyi

2018-05-01

Particle Swarm Optimization (PSO) is a well-known meta-heuristic. It has been widely used in both research and engineering fields. However, the original PSO generally suffers from premature convergence, especially in multimodal problems. In this paper, we propose a double-group PSO (DG-PSO) algorithm to improve the performance. DG-PSO uses a double-group based evolution framework. The individuals are divided into two groups: an advantaged group and a disadvantaged group. The advantaged group works according to the original PSO, while two new strategies are developed for the disadvantaged group. The proposed algorithm is firstly evaluated by comparing it with the other five popular PSO variants and two state-of-the-art meta-heuristics on various benchmark functions. The results demonstrate that DG-PSO shows a remarkable performance in terms of accuracy and stability. Then, we apply DG-PSO to multilevel thresholding for remote sensing image segmentation. The results show that the proposed algorithm outperforms five other popular algorithms in meta-heuristic-based multilevel thresholding, which verifies the effectiveness of the proposed algorithm.

Generalization of Random Intercept Multilevel Models

Directory of Open Access Journals (Sweden)

Rehan Ahmad Khan

2013-10-01

Full Text Available The concept of random intercept models in a multilevel model developed by Goldstein (1986 has been extended for k-levels. The random variation in intercepts at individual level is marginally split into components by incorporating higher levels of hierarchy in the single level model. So, one can control the random variation in intercepts by incorporating the higher levels in the model.

IgG4 and IgE co-positive group found in idiopathic orbital inflammatory disease

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Peng-Xiang Zhao

2018-01-01

Full Text Available AIM: To reveal the cytokines involved in idiopathic orbital inflammatory disease (IOID and the relationship between Th17 cells, IgE and IOID pathogenesis. METHODS: Whole blood samples were processed immediately after collection and serological IgG4, IgG, and IgE antibodies were tested using ELISA. IOID and orbital cavernous hemangioma (CH tissue samples underwent Bio-Plex multiplex cytokine detection. Hematoxylin-Eosin (HE staining of all paraffin samples suggested the histological features of IOIDs, and expressions of IgG4 and IL-17A in affected tissues were detected by immunohistochemistry. RESULTS: Among 40 IOID plasma samples, 52.5% (21/40 were positive for IgG4 and 25% (10/40 were positive for IgE. Overlapped IgG4 or IgE positive samples accounted for 22.5% (9/40. Therefore, IOID samples were separated into three groups. The IgE+/IgG4+ group had a relevantly lower level of pro-inflammatory cytokine expression. IL-4 (Th2 cell related, IL-10 and TGF-β1 (Treg cell immunity related were elevated in all three groups. Some of the Th17 cell related cytokines (i.e. IL-17A/F, IL-25, IL-23, and IL-33 displayed higher expression levels in the IgE-/IgG4- group compared to the other two groups. CONCLUSION: We discovered an IgG4-IgE co-positive group as well as Th17 cell immune involvement in IgG4-IgE co-negative subgtroup in IOID for the first time. The pathogenesis of IOID could differ from different subgroups according to the IgG4 and IgE detection. Therefore, we recommend that, Treatment stratagy should be made according to the clinical assessment of IgG4-IgE and Th17 profile detection.

Multi-level Reconfigurable Self-organization in Overlay Services

NARCIS (Netherlands)

Pournaras, E.

2013-01-01

Large-scale decentralized systems organized in overlay networks are complex to manage. Such systems integrate organizational complexity in the application-level resulting in low abstraction and modularity in their services. This thesis introduces a multi-level conceptual architecture for overlay

Challenges for Multilevel Health Disparities Research in a Transdisciplinary Environment

Science.gov (United States)

Holmes, John H.; Lehman, Amy; Hade, Erinn; Ferketich, Amy K.; Sarah, Gehlert; Rauscher, Garth H.; Abrams, Judith; Bird, Chloe E.

2008-01-01

Numerous factors play a part in health disparities. Although health disparities are manifested at the level of the individual, other contexts should be considered when investigating the associations of disparities with clinical outcomes. These contexts include families, neighborhoods, social organizations, and healthcare facilities. This paper reports on health disparities research as a multilevel research domain from the perspective of a large national initiative. The Centers for Population Health and Health Disparities (CPHHD) program was established by the NIH to examine the highly dimensional, complex nature of disparities and their effects on health. Because of its inherently transdisciplinary nature, the CPHHD program provides a unique environment in which to perform multilevel health disparities research. During the course of the program, the CPHHD centers have experienced challenges specific to this type of research. The challenges were categorized along three axes: sources of subjects and data, data characteristics, and multilevel analysis and interpretation. The CPHHDs collectively offer a unique example of how these challenges are met; just as importantly, they reveal a broad range of issues that health disparities researchers should consider as they pursue transdisciplinary investigations in this domain, particularly in the context of a large team science initiative. PMID:18619398

Multilevel control of the metastable states in a manganite film

Science.gov (United States)

Jin, Feng; Feng, Qiyuan; Guo, Zhuang; Lan, Da; Chen, Binbin; Xu, Haoran; Wang, Ze; Wang, Lingfei; Gao, Guanyin; Chen, Feng; Lu, Qingyou; Wu, Wenbin

2017-06-01

For high density memory applications, the dynamic switching between multilevel resistance states per cell is highly desirable, and for oxide-based memory devices, the multistate operation has been actively explored. We have previously shown that for La2/3Ca1/3MnO3 films, the antiferromagnetic charge-ordered-insulator (COI) phase can be induced via the anisotropic epitaxial strain, and it competes with the doping-determined ferromagnetic-metal (FMM) ground state in a wide temperature range. Here, we show that for the phase competitions, in various magnetic fields and/or thermal cycling, the reappearance of the COI phase and thus the resistance and magnetization can be manipulated and quantified in a multilevel manner at lower temperatures. Furthermore, by using a high-field magnetic force microscope, we image the COI/FMM domain structures in accordance with the transport measurements, and find that the evolving domains or the phase fraction ratios do underline the metastability of the reappeared COI droplets, possibly protected by the energy barriers due to accommodation strain. These results may add new insights into the design and fabrication of future multilevel memory cells.

Job demands, burnout, and engagement among nurses: A multi-level analysis of ORCAB data investigating the moderating effect of teamwork.

Science.gov (United States)

Montgomery, Anthony; Spânu, Florina; Băban, Adriana; Panagopoulou, Efharis

2015-09-01

According to the Job Demands-Resources (JD-R) model, burnout and engagement are psychological reactions that develop when individual characteristics interact with work characteristics. This study tests the JD-R model using multilevel analysis to test the main and moderating effects of teamwork effectiveness among 1156 nurses in 93 departments from seven European countries. Workload, emotional and organizational demands were positively associated with emotional exhaustion, depersonalization, and negatively with vigor. Emotional and organizational demands were negatively associated with dedication. Teamwork effectiveness was positively associated with engagement. We found no evidence for the moderating effect of teamwork effectiveness in reducing individual perceptions of demands.

Engineering applications of heuristic multilevel optimization methods

Science.gov (United States)

Barthelemy, Jean-Francois M.

1989-01-01

Some engineering applications of heuristic multilevel optimization methods are presented and the discussion focuses on the dependency matrix that indicates the relationship between problem functions and variables. Coordination of the subproblem optimizations is shown to be typically achieved through the use of exact or approximate sensitivity analysis. Areas for further development are identified.

The "hierarchical" Scratch Collapse Test for identifying multilevel ulnar nerve compression.

Science.gov (United States)

Davidge, Kristen M; Gontre, Gil; Tang, David; Boyd, Kirsty U; Yee, Andrew; Damiano, Marci S; Mackinnon, Susan E

2015-09-01

The Scratch Collapse Test (SCT) is used to assist in the clinical evaluation of patients with ulnar nerve compression. The purpose of this study is to introduce the hierarchical SCT as a physical examination tool for identifying multilevel nerve compression in patients with cubital tunnel syndrome. A prospective cohort study (2010-2011) was conducted of patients referred with primary cubital tunnel syndrome. Five ulnar nerve compression sites were evaluated with the SCT. Each site generating a positive SCT was sequentially "frozen out" with a topical anesthetic to allow determination of both primary and secondary ulnar nerve entrapment points. The order or "hierarchy" of compression sites was recorded. Twenty-five patients (mean age 49.6 ± 12.3 years; 64 % female) were eligible for inclusion. The primary entrapment point was identified as Osborne's band in 80 % and the cubital tunnel retinaculum in 20 % of patients. Secondary entrapment points were also identified in the following order in all patients: (1) volar antebrachial fascia, (2) Guyon's canal, and (3) arcade of Struthers. The SCT is useful in localizing the site of primary compression of the ulnar nerve in patients with cubital tunnel syndrome. It is also sensitive enough to detect secondary compression points when primary sites are sequentially frozen out with a topical anesthetic, termed the hierarchical SCT. The findings of the hierarchical SCT are in keeping with the double crush hypothesis described by Upton and McComas in 1973 and the hypothesis of multilevel nerve compression proposed by Mackinnon and Novak in 1994.

Translating the Social-Ecological Perspective into Multilevel Interventions for Family Planning: How Far Are We?

Science.gov (United States)

Schölmerich, Vera L. N.; Kawachi, Ichiro

2016-01-01

Scholars and practitioners frequently make recommendations to develop family planning interventions that are "multilevel." Such interventions take explicit account of the role of environments by incorporating multilevel or social-ecological frameworks into their design and implementation. However, research on how interventions have…

PLTS Transformerless Tegangan 20 kV menggunakan Cascaded H-Bridge Multilevel Inverter

Directory of Open Access Journals (Sweden)

ANGGARA BRAJAMUSTHI

2018-03-01

Full Text Available ABSTRAK Aplikasi dari inverter multilevel pada sistem Pusat Listrik Tenaga Surya (PLTS dapat menghilangkan kebutuhan terhadap transformator, sehingga dapat mengurangi biaya investasi, mengurangi kompleksitas instalasi dan menghilangkan rugi-rugi daya transformator. Pada penelitian ini, sebuah inverter dengan topologi Cascaded H-Bridge Multilevel Inverter dirancang agar mampu mengubah tegangan rendah DC dari beberapa Photovoltaic (PV array menjadi tegangan fasa-fasa 20 kV AC. Perancangan menghasilkan sebuah inverter 3 fasa 27-level dimana setiap level masing-masing memiliki PV array, DC-DC boost converter, H-bridge inverter, dan keluaran 3 fasa terhubung dengan filter LCL. Setiap komponen dari inverter dan sistem tersebut kemudian dimodelkan pada MATLAB Simulink untuk mensimulasikan kinerja dari setiap komponen dan sistem pada Standard Test Condition (STC dari modul PV. Pada keadaan STC, daya 3 fasa maksimum yang dapat dihasilkan adalah 1,716 MW atau 68,54% dari daya DC maksimum sebesar 2,5 MWp. Sistem dapat menghasilkan tegangan fasa-fasa keluaran sebesar 20 kV dengan Total Harmonic Distortion (THD di bawah 5%. Kata kunci: Pusat Listrik Tenaga Surya (PLTS, photovoltaic, Cascaded H-Bridge Multilevel Inverter ABSTRACT The application of Multilevel Inverter in a Photovoltaic Solar Power Plant system could eliminate the needs of step-up transformer, which will reduce the system investment cost, simplify the system installation and also eliminate power losses of the transformer. In this paper, an inverter design was proposed with Cascaded H-Bridge Multilevel Inverter topology that is capable of converting low voltage DC power from several PV arrays into 20 kV AC power. The design resulted a 3 phase 27-level inverter where each level in the inverter has its own photovoltaic array, DC-DC boost converter, H-bridge inverter, and the 3 phase output is connected to LCL filter. Each component of the Inverter and the system were then modelled in MATLAB

Intergroup Contact and Social Change: Implications of Negative and Positive Contact for Collective Action in Advantaged and Disadvantaged Groups.

Science.gov (United States)

Reimer, Nils Karl; Becker, Julia C; Benz, Angelika; Christ, Oliver; Dhont, Kristof; Klocke, Ulrich; Neji, Sybille; Rychlowska, Magdalena; Schmid, Katharina; Hewstone, Miles

2017-01-01

Previous research has shown that (a) positive intergroup contact with an advantaged group can discourage collective action among disadvantaged-group members and (b) positive intergroup contact can encourage advantaged-group members to take action on behalf of disadvantaged outgroups. Two studies investigated the effects of negative as well as positive intergroup contact. Study 1 ( n = 482) found that negative but not positive contact with heterosexual people was associated with sexual-minority students' engagement in collective action (via group identification and perceived discrimination). Among heterosexual students, positive and negative contacts were associated with, respectively, more and less LGB (lesbian, gay, bisexual) activism. Study 2 ( N = 1,469) found that only negative contact (via perceived discrimination) predicted LGBT (lesbian, gay, bisexual, and transgender) students' collective action intentions longitudinally while only positive contact predicted heterosexual/cisgender students' LGBT activism. Implications for the relationship between intergroup contact, collective action, and social change are discussed.

A Single-Phase Multilevel PV Generation System with an Improved Ripple Correlation Control MPPT Algorithm

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Manel Hammami

2017-12-01

Full Text Available The implementation of maximum power point tracking (MPPT schemes by the ripple correlation control (RCC algorithm is presented in this paper. A reference is made to single-phase single-stage multilevel photovoltaic (PV generation systems, when the inverter input variables (PV voltage and PV current have multiple low-frequency (ripple harmonics. The harmonic analysis is carried out with reference to a multilevel configuration consisting of an H-bridge inverter and level doubling network (LDN cell, leading to the multilevel inverter having double the output voltage levels as compared to the basic H-bridge inverter topology (i.e., five levels vs. three levels. The LDN cell is basically a half-bridge fed by a floating capacitor, with self-balancing voltage capability. The multilevel configuration introduces additional PV voltage and current low-frequency harmonics, perturbing the basic implementation of the RCC scheme (based on the second harmonic component, leading to malfunctioning. The proposed RCC algorithm employs the PV current and voltage harmonics at a specific frequency for the estimation of the voltage derivative of power dP/dV (or dI/dV, driving the PV operating point toward the maximum power point (MPP in a faster and more precise manner. The steady-state and transient performances of the proposed RCC-MPPT schemes have been preliminarily tested and compared using MATLAB/Simulink. Results have been verified by experimental tests considering the whole multilevel PV generation system, including real PV modules, multilevel insulated-gate bipolar transistor (IGBT inverters, and utility grids.

Virtual-vector-based space vector pulse width modulation of the DC-AC multilevel-clamped multilevel converter (MLC²)

DEFF Research Database (Denmark)

Rodriguez, Pedro; Busquets-Monge, Sergio; Blaabjerg, Frede

2011-01-01

This work presents the development of the space vector pulse width modulation (SVPWM) of a new multi-level converter topology. First, the proposed converter and its natural space vector diagram are presented. Secondly, a modified space vector diagram based on the virtual-vectors technique is show...

Representations of the Poincare group, position operator and the bi-local model

International Nuclear Information System (INIS)

Sohkawa, Tohru

1978-01-01

We propose two types of representations of the Poincare group which give general frameworks for introduction of internal degrees of freedom of a particle. The bi-local model recently proposed by Takabayasi is constructed through our frameworks. In this study, new covariant and non-covariant position operators are introduced and discussed. (author)

Developing Multi-Level Institutions from Top-Down Ancestors

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Martha Dowsley

2007-11-01

Full Text Available The academic literature contains numerous examples of the failures of both top-down and bottom-up common pool resource management frameworks. Many authors agree that management regimes instead need to utilize a multi-level governance approach to meet diverse objectives in management. However, many currently operating systems do not have that history. This paper explores the conversion of ancestral top-down regimes to complex systems involving multiple scales, levels and objectives through the management of the polar bear (Ursus maritimus in its five range countries. The less successful polar bear management systems continue to struggle with the challenges of developing institutions with the capacity to learn and change, addressing multiple objectives while recognizing the conservation backbone to management, and matching the institutional scale with biophysical, economic and social scales. The comparatively successful institutions incorporate these features, but reveal on-going problems with vertical links that are partially dealt with through the creation of links to other groups.

Innovation in Multi-Level Governance for Energy Efficiency. Sharing experience with multi-level governance to enhance energy efficiency. Information paper

Energy Technology Data Exchange (ETDEWEB)

Jollands, Nigel; Gasc, Emilien; Pasquier, Sara Bryan

2009-12-15

Despite creating a plethora of national and international regulations and voluntary programmes to improve energy efficiency, countries are far from achieving full energy efficiency potential across all sectors of the economy. One major challenge, among numerous barriers, is policy implementation. One strategy that many national governments and international organisations have used to address the implementation issue is to engage regional and local authorities. To that end, many programmes have been created that foster energy efficiency action and collaboration across levels of government. The aim of this report is to identify trends and detail recent developments in multi-level governance in energy efficiency (MLGEE). By sharing lessons learned from daily practitioners in the field, the IEA hopes energy efficiency policy makers at all levels of government will be able to identify useful multilevel governance (MLG) practices across geographical and political contexts and use these to design robust programmes; modify existing programmes, and connect and share experiences with other policy makers in this field.

Multilevel interventions aimed at adult obesity prevention

DEFF Research Database (Denmark)

Benwell, Ann Fenger

A growing body of literature emphasizes the importance of using both quantitative and qualitative methods to investigate the wide range of aspects which hinder or promote the success of health interventions. The pilot phase of this study highlights how mixed-method approaches can be strengthened ...... to investigate factors associated with multi-level obesity prevention....

Leveling up? An inter-neighborhood experiment on parochialism and the efficiency of multi-level public goods provision

OpenAIRE

Gallier, Carlo; Goeschl, Timo; Kesternich, Martin; Lohse, Johannes; Reif, Christiane; Römer, Daniel

2017-01-01

Many public goods can be provided at different spatial levels. Evidence from social identity theory and in-group favoritism raises the possibility that where higher-level provision is more efficient, subjects’ narrow concern for local outcomes (parochialism) could harm efficiency. Building on the experimental paradigm of multi-level public good games and the ‘neighborhood attachment’ concept, we conduct an artefactual field experiment with 600 participants in a setting conducive to parochial...

Analyzing the Role of Multi-level Learning in Implementing computerized HIS in Developing Countries

DEFF Research Database (Denmark)

Mengiste, Shegaw Anagaw

2008-01-01

This paper presents a perspective for looking at the development and implementation of large scale computerised HIS as a multi-level learning process. Drawing on the empirical evidences from the ongoing Health Information systems program ( HISP) initiatives on the development, customization...... and implementation of computerised HIS in Ethiopia, the paper analyses the learning mechanisms, learning outcomes and obstacles for learning at individual, group, and organizational levels. Empirical data on two distinct phases of software development and customization (District health Information Software (DHIS......) versions 1.3 and 2.0) are contrasted. More specifically, we tried to show the dynamics of learning and the specific learning mechanisms by analysing and contrasting the interaction between IS developers and public health care domain experts, technological capacity at individual, group, and organizational...

THD Minimization from H-Bridge Cascaded Multilevel Inverter Using Particle Swarm Optimization Technique

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MUDASIR AHMED MEMON

2017-01-01

Full Text Available In this paper, PSO (Particle Swarm Optimization based technique is proposed to derive optimized switching angles that minimizes the THD (Total Harmonic Distortion and reduces the effect of selected low order non-triple harmonics from the output of the multilevel inverter. Conventional harmonic elimination techniques have plenty of limitations, and other heuristic techniques also not provide the satisfactory results. In this paper, single phase symmetrical cascaded H-Bridge 11-Level multilevel inverter is considered, and proposed algorithm is utilized to obtain the optimized switching angles that reduced the effect of 5th, 7th, 11th and 13th non-triplen harmonics from the output voltage of the multilevel inverter. A simulation result indicates that this technique outperforms other methods in terms of minimizing THD and provides high-quality output voltage waveform.

THD minimization from h-bridge cascaded multilevel inverter using particle swarm optimization technique

International Nuclear Information System (INIS)

Memon, M.A.; Memon, S.; Khan, S.

2017-01-01

In this paper, PSO (Particle Swarm Optimization) based technique is proposed to derive optimized switching angles that minimizes the THD (Total Harmonic Distortion) and reduces the effect of selected low order non-triple harmonics from the output of the multilevel inverter. Conventional harmonic elimination techniques have plenty of limitations, and other heuristic techniques also not provide the satisfactory results. In this paper, single phase symmetrical cascaded H-Bridge 11-Level multilevel inverter is considered, and proposed algorithm is utilized to obtain the optimized switching angles that reduced the effect of 5th, 7th, 11th and 13th non-triplen harmonics from the output voltage of the multilevel inverter. A simulation result indicates that this technique outperforms other methods in terms of minimizing THD and provides high-quality output voltage waveform. (author)

Constructing and validating readability models: the method of integrating multilevel linguistic features with machine learning.

Science.gov (United States)

Sung, Yao-Ting; Chen, Ju-Ling; Cha, Ji-Her; Tseng, Hou-Chiang; Chang, Tao-Hsing; Chang, Kuo-En

2015-06-01

Multilevel linguistic features have been proposed for discourse analysis, but there have been few applications of multilevel linguistic features to readability models and also few validations of such models. Most traditional readability formulae are based on generalized linear models (GLMs; e.g., discriminant analysis and multiple regression), but these models have to comply with certain statistical assumptions about data properties and include all of the data in formulae construction without pruning the outliers in advance. The use of such readability formulae tends to produce a low text classification accuracy, while using a support vector machine (SVM) in machine learning can enhance the classification outcome. The present study constructed readability models by integrating multilevel linguistic features with SVM, which is more appropriate for text classification. Taking the Chinese language as an example, this study developed 31 linguistic features as the predicting variables at the word, semantic, syntax, and cohesion levels, with grade levels of texts as the criterion variable. The study compared four types of readability models by integrating unilevel and multilevel linguistic features with GLMs and an SVM. The results indicate that adopting a multilevel approach in readability analysis provides a better representation of the complexities of both texts and the reading comprehension process.

Multi-level programming paradigm for extreme computing

International Nuclear Information System (INIS)

Petiton, S.; Sato, M.; Emad, N.; Calvin, C.; Tsuji, M.; Dandouna, M.

2013-01-01

In order to propose a framework and programming paradigms for post peta-scale computing, on the road to exa-scale computing and beyond, we introduced new languages, associated with a hierarchical multi-level programming paradigm, allowing scientific end-users and developers to program highly hierarchical architectures designed for extreme computing. In this paper, we explain the interest of such hierarchical multi-level programming paradigm for extreme computing and its well adaptation to several large computational science applications, such as for linear algebra solvers used for reactor core physic. We describe the YML language and framework allowing describing graphs of parallel components, which may be developed using PGAS-like language such as XMP, scheduled and computed on supercomputers. Then, we propose experimentations on supercomputers (such as the 'K' and 'Hooper' ones) of the hybrid method MERAM (Multiple Explicitly Restarted Arnoldi Method) as a case study for iterative methods manipulating sparse matrices, and the block Gauss-Jordan method as a case study for direct method manipulating dense matrices. We conclude proposing evolutions for this programming paradigm. (authors)

Plasma simulation studies using multilevel physics models

International Nuclear Information System (INIS)

Park, W.; Belova, E.V.; Fu, G.Y.

2000-01-01

The question of how to proceed toward ever more realistic plasma simulation studies using ever increasing computing power is addressed. The answer presented here is the M3D (Multilevel 3D) project, which has developed a code package with a hierarchy of physics levels that resolve increasingly complete subsets of phase-spaces and are thus increasingly more realistic. The rationale for the multilevel physics models is given. Each physics level is described and examples of its application are given. The existing physics levels are fluid models (3D configuration space), namely magnetohydrodynamic (MHD) and two-fluids; and hybrid models, namely gyrokinetic-energetic-particle/MHD (5D energetic particle phase-space), gyrokinetic-particle-ion/fluid-electron (5D ion phase-space), and full-kinetic-particle-ion/fluid-electron level (6D ion phase-space). Resolving electron phase-space (5D or 6D) remains a future project. Phase-space-fluid models are not used in favor of delta f particle models. A practical and accurate nonlinear fluid closure for noncollisional plasmas seems not likely in the near future

Does school social capital modify socioeconomic inequality in mental health? A multi-level analysis in Danish schools.

Science.gov (United States)

Nielsen, Line; Koushede, Vibeke; Vinther-Larsen, Mathilde; Bendtsen, Pernille; Ersbøll, Annette Kjær; Due, Pernille; Holstein, Bjørn E

2015-09-01

It seems that social capital in the neighbourhood has the potential to reduce socioeconomic differences in mental health among adolescents. Whether school social capital is a buffer in the association between socioeconomic position and mental health among adolescents remains uncertain. The aim of this study is therefore to examine if the association between socioeconomic position and emotional symptoms among adolescents is modified by school social capital. The Health Behaviour in School-aged Children Methodology Development Study 2012 provided data on 3549 adolescents aged 11-15 in two municipalities in Denmark. Trust in the school class was used as an indicator of school social capital. Prevalence of daily emotional symptoms in each socioeconomic group measured by parents' occupational class was calculated for each of the three categories of school classes: school classes with high trust, moderate trust and low trust. Multilevel logistic regression analyses with parents' occupational class as the independent variable and daily emotional symptoms as the dependent variable were conducted stratified by level of trust in the school class. The prevalence of emotional symptoms was higher among students in school classes with low trust (12.9%) compared to school classes with high trust (7.2%) (p social capital may reduce mental health problems and diminish socioeconomic inequality in mental health among adolescents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Multi-level governance of forest resources (Editorial to the special feature

Directory of Open Access Journals (Sweden)

Esther Mwangi

2012-08-01

Full Text Available A major challenge for many researchers and practitioners relates to how to recognize and address cross-scale dynamics in space and over time in order to design and implement effective governance arrangements. This editorial provides an overview of the concept of multi-level governance (MLG. In particular we highlight definitional issues, why the concept matters as well as more practical concerns related to the processes and structure of multi-level governance. It is increasingly clear that multi-level governance of forest resources involves complex interactions of state, private and civil society actors at various levels, and institutions linking higher levels of social and political organization. Local communities are increasingly connected to global networks and influences. This creates new opportunities to learn and address problems but may also introduce new pressures and risks. We conclude by stressing the need for a much complex approach to the varieties of MLG to better understand how policies work as instruments of governance and to organize communities within systems of power and authority.

Multi-level Control Framework for Enhanced Flexibility of Active Distribution Network

DEFF Research Database (Denmark)

Nainar, Karthikeyan; Pokhrel, Basanta Raj; Pillai, Jayakrishnan Radhakrishna

2017-01-01

In this paper, the control objectives of future active distribution networks with high penetration of renewables and flexible loads are analyzed and reviewed. From a state of the art review, the important control objectives seen from the perspective of a distribution system operator are identifie......-ordination and management of the network assets at different voltage levels and geographical locations. The paper finally shows the applicability of the multi-level control architecture to some of the key challenges in the distribution system operation by relevant scenarios....... to be hosting capacity improvement, high reliable operation and cost effective network management. Based on this review and a state of the art review concerning future distribution network control methods, a multi-level control architecture is constructed for an active distribution network, which satisfies...... the selected control objectives and provides enhanced flexibility. The control architecture is supported by generation/load forecasting and distribution state estimation techniques to improve the controllability of the network. The multi-level control architecture consists of three levels of hierarchical...

Design and installation of deep multilevel piezometer nests in Columbia River basalts at the Hanford Site, Washington

International Nuclear Information System (INIS)

Jackson, R.L.; Veatch, M.D.

1985-04-01

The Basalt Waste Isolation Project (BWIP) was established in 1976 as part of the National Waste Terminal Storage Program, now the Office of Civilian Radioactive Waste Management. The BWIP objective is to assess the suitability of basalt as a repository medium for the long-term storage of commercial high-level radioactive waste. As part of the hydrogeologic characterization activities, BWIP designed and installed multilevel piezometer nests at three borehole cluster sites within and adjacent to the 18-square-mile reference repository location. These borehole cluster sites will provide multilevel piezometric baseline data across the reference repository location prior to, during, and after drilling a large-diameter exploratory shaft. They will also be used to monitor future hydraulic stress tests on a large scale. Three series of piezometer nests (A-, C-, and D-series) were installed at three borehole cluster sites in nine hydrogeologic units from a depth of about 500 to 3700 feet within the Columbia River Basalt Group. These multilevel monitoring zones are isolated from each other and the next overlying hydrogeologic unit by high-density cement seals. The A-series piezometer nests monitor two shallow sedimentary units. The C-series piezometer nests monitor basalt flow tops in the six deepest zones. The D-series piezometer monitors an intermediate sedimentary unit. Each piezometer tube was developed by air-lift pumping to complete the installtion prior to installing downhole pressure transducers. 23 refs., 10 figs., 1 tab

Age, forgiveness, and meeting behavior: A multilevel study

NARCIS (Netherlands)

Schulte, E.-M.; Lehmann-Willenbrock, N.K.; Kauffeld, S.

2013-01-01

Purpose: This paper aims to examine the effects of age on counteractive team meeting behaviors (e.g. complaining). Forgiveness is included as a potential buffer against these behaviors. A multilevel model is developed to test individual and team level age effects. Design/methodology/approach: A

Determinants of Academic Entrepreneurship Behavior: A Multilevel Model

Science.gov (United States)

Llano, Joseph Anthony

2010-01-01

It is well established that universities encourage the acquisition and dissemination of new knowledge among university community members and beyond. However, what is less well understood is how universities encourage entrepreneurial (opportunity discovery, evaluation, and exploiting) behavior. This research investigated a multilevel model of the…

Attachment, Autonomy, and Emotional Reliance: A Multilevel Model

Science.gov (United States)

Lynch, Martin F.

2013-01-01

This article reports a test of a multilevel model investigating how attachment security and autonomy contribute to emotional reliance, or the willingness to seek interpersonal support. Participants ("N" = 247) completed online measures of attachment, autonomy, emotional reliance, and vitality with respect to several everyday…

Studying historical occupational careers with multilevel growth models

NARCIS (Netherlands)

Schulz, W.; Maas, I.

2010-01-01

In this article we propose to study occupational careers with historical data by using multilevel growth models. Historical career data are often characterized by a lack of information on the timing of occupational changes and by different numbers of observations of occupations per individual.

Comparison of the Anaerobic Power of Brazilian Professional Football Players Grouped by Tactical Position

Directory of Open Access Journals (Sweden)

Renan Renato Cruz dos Santos

2014-09-01

Full Text Available Football is characterized as a predominately aerobic modality, however, during a match; the most important actions performed by the players are in short duration and high intensity. In addition, this sport presents to have some particularities, such as, highlights differences of each tactical position. Thus, this study aimed to compare the anaerobic power of professional football players grouped by different tactical positions. Thirty professional football players separated in three groups, goal¬keep¬ers+fullbacks, sideways+DMF (defensive middlefields and OMF (offensive middlefields+forwards, performed two anaerobic po¬wer tests, Running anaerobic sprint test and Sargent jump test Goalkeepers+fullbacks showed higher values of body mass index and absolute anaerobic power (w, using Sargent jump test than the others, but when analyzed the RAST results, this same group presented lower values (p<0.05 of relative AP (w∙kg-1. OMF+forwards showed to have the best Pmed and Pmax values (p<0.05, when compared with defensive players. These results suggest the use of running anaerobic sprint test and sargent jump test toge¬ther when is proposed to measure the anaerobic power of football players, and also a anthropometric evaluation, so the training can be more specific e efficient to each tactical position and athlete.

Effects of body position and sex group on tongue pressure generation.

Science.gov (United States)

Dietsch, Angela M; Cirstea, Carmen M; Auer, Ed T; Searl, Jeff P

2013-11-01

Fine control of orofacial musculature is necessary to precisely accelerate and decelerate the articulators across exact distances for functional speech and coordinated swallows (Amerman & Parnell, 1990; Benjamin, 1997; Kent, Duffy, Slama, Kent, & Clift, 2001). Enhanced understanding of neural control for such movements could clarify the nature of and potential remediation for some dysarthrias and other orofacial myofunctional impairments. Numerous studies have measured orolingual force and accuracy during speech and nonspeech tasks, but have focused on young adults, maximum linguapalatal pressures, and upright positioning (O'Day, Frank, Montgomery, Nichols, & McDade, 2005; Solomon & Munson, 2004; Somodi, Robin, & Luschei, 1995; Youmans, Youmans, & Stierwalt, 2009). Patients' medical conditions or testing procedures such as concurrent neuroimaging may preclude fully upright positioning during oral motor assessments in some cases. Since judgments about lingual strength and coordination can influence clinical decisions regarding the functionality of swallowing and speech, it is imperative to understand any effects of body positioning differences. In addition, sex differences in the control of such tasks are not well defined. Therefore, this study evaluated whether pressures exerted during tongue movements differ in upright vs. supine body position in healthy middle-aged men and women. Twenty healthy middle-aged adults compressed small air-filled plastic bulbs in the oral cavity at predetermined fractions of task-specific peak pressure in a randomized block design. Tasks including phoneme repetitions and nonspeech isometric contractions were executed in upright and supine positions. Participants received continuous visual feedback regarding targets and actual exerted pressures. Analyses compared average pressure values for each subject, task, position, and effort level. Speech-like and nonspeech tongue pressures did not differ significantly across body position or sex

Multilevel processes and cultural adaptation: Examples from past and present small-scale societies

OpenAIRE

Reyes-García, V.; Balbo, A. L.; Gomez-Baggethun, E.; Gueze, M.; Mesoudi, A.; Richerson, P.; Rubio-Campillo, X.; Ruiz-Mallén, I.; Shennan, S.

2016-01-01

Cultural adaptation has become central in the context of accelerated global change with authors increasingly acknowledging the importance of understanding multilevel processes that operate as adaptation takes place. We explore the importance of multilevel processes in explaining cultural adaptation by describing how processes leading to cultural (mis)adaptation are linked through a complex nested hierarchy, where the lower levels combine into new units with new organizations, functions, and e...

The relationship between group size, intoxication and continuing to drink after bar attendance.

Science.gov (United States)

Reed, Mark B; Clapp, John D; Martell, Brandi; Hidalgo-Sotelo, Alexandra

2013-11-01

The present study was undertaken to explore multilevel determinants of planning to continue to drink alcohol after leaving public drinking events. We assessed whether individual-level factors, group-related factors, or event-level bar characteristics were associated with post-bar drinking. We recruited a total of 642 participants from 30 participating bars in urban Southern California. Groups who arrived to patron a bar were interviewed upon their entrance and exit. Given data nesting, we employed a multilevel modeling approach to data analysis. More than one-third (40%) of our sample reported the intention to continue drinking as they exited the bar. Results of our multilevel model indicated eight individual-level variables significantly associated with intending to continue to drink. Time of night moderated the relationship between BrAC change and intentions to continue to drink. Although none of the group factors were significant in our model, a significant cross-level interaction between BrAC change and number of group members indicated the effect of intoxication on planning to continue to drink increases as group members increase. At the bar level, the presence of temporary bars and server offers of non-alcoholic drinks significantly decreased intentions to continue to drink. Given the large percentage of participants who reported the intention to continue drinking after exiting a bar, this study draws attention to the fact that field studies of drinking behavior may assess drinking mid-event rather than at the end of a drinking event. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Hybrid dual gate ferroelectric memory for multilevel information storage

KAUST Repository

Khan, Yasser

2015-01-01

Here, we report hybrid organic/inorganic ferroelectric memory with multilevel information storage using transparent p-type SnO semiconductor and ferroelectric P(VDF-TrFE) polymer. The dual gate devices include a top ferroelectric field-effect transistor (FeFET) and a bottom thin-film transistor (TFT). The devices are all fabricated at low temperatures (∼200°C), and demonstrate excellent performance with high hole mobility of 2.7 cm2 V-1 s-1, large memory window of ∼18 V, and a low sub-threshold swing ∼-4 V dec-1. The channel conductance of the bottom-TFT and the top-FeFET can be controlled independently by the bottom and top gates, respectively. The results demonstrate multilevel nonvolatile information storage using ferroelectric memory devices with good retention characteristics.

Multi-level tree analysis of pulmonary artery/vein trees in non-contrast CT images

Science.gov (United States)

Gao, Zhiyun; Grout, Randall W.; Hoffman, Eric A.; Saha, Punam K.

2012-02-01

Diseases like pulmonary embolism and pulmonary hypertension are associated with vascular dystrophy. Identifying such pulmonary artery/vein (A/V) tree dystrophy in terms of quantitative measures via CT imaging significantly facilitates early detection of disease or a treatment monitoring process. A tree structure, consisting of nodes and connected arcs, linked to the volumetric representation allows multi-level geometric and volumetric analysis of A/V trees. Here, a new theory and method is presented to generate multi-level A/V tree representation of volumetric data and to compute quantitative measures of A/V tree geometry and topology at various tree hierarchies. The new method is primarily designed on arc skeleton computation followed by a tree construction based topologic and geometric analysis of the skeleton. The method starts with a volumetric A/V representation as input and generates its topologic and multi-level volumetric tree representations long with different multi-level morphometric measures. A new recursive merging and pruning algorithms are introduced to detect bad junctions and noisy branches often associated with digital geometric and topologic analysis. Also, a new notion of shortest axial path is introduced to improve the skeletal arc joining two junctions. The accuracy of the multi-level tree analysis algorithm has been evaluated using computer generated phantoms and pulmonary CT images of a pig vessel cast phantom while the reproducibility of method is evaluated using multi-user A/V separation of in vivo contrast-enhanced CT images of a pig lung at different respiratory volumes.

A brief conceptual tutorial of multilevel analysis in social epidemiology: using measures of clustering in multilevel logistic regression to investigate contextual phenomena

DEFF Research Database (Denmark)

Merlo, J; Chaix, B; Ohlsson, H

2006-01-01

STUDY OBJECTIVE: In social epidemiology, it is easy to compute and interpret measures of variation in multilevel linear regression, but technical difficulties exist in the case of logistic regression. The aim of this study was to present measures of variation appropriate for the logistic case...... in a didactic rather than a mathematical way. Design and PARTICIPANTS: Data were used from the health survey conducted in 2000 in the county of Scania, Sweden, that comprised 10 723 persons aged 18-80 years living in 60 areas. Conducting multilevel logistic regression different techniques were applied...... propensity areas with the area educational level. The sorting out index was equal to 82%. CONCLUSION: Measures of variation in logistic regression should be promoted in social epidemiological and public health research as efficient means of quantifying the importance of the context of residence...

Hybrid dual gate ferroelectric memory for multilevel information storage

KAUST Repository

Khan, Yasser; Caraveo-Frescas, Jesus Alfonso; Alshareef, Husam N.

2015-01-01

Here, we report hybrid organic/inorganic ferroelectric memory with multilevel information storage using transparent p-type SnO semiconductor and ferroelectric P(VDF-TrFE) polymer. The dual gate devices include a top ferroelectric field

Multilevel solvers of first-order system least-squares for Stokes equations

Energy Technology Data Exchange (ETDEWEB)

Lai, Chen-Yao G. [National Chung Cheng Univ., Chia-Yi (Taiwan, Province of China)

1996-12-31

Recently, The use of first-order system least squares principle for the approximate solution of Stokes problems has been extensively studied by Cai, Manteuffel, and McCormick. In this paper, we study multilevel solvers of first-order system least-squares method for the generalized Stokes equations based on the velocity-vorticity-pressure formulation in three dimensions. The least-squares functionals is defined to be the sum of the L{sup 2}-norms of the residuals, which is weighted appropriately by the Reynolds number. We develop convergence analysis for additive and multiplicative multilevel methods applied to the resulting discrete equations.

Development of a Causal Framework linking High Perofrmance HRM Practices, Positive Psychological Capital, Creative Behaviours

OpenAIRE

Gupta, Vishal

2013-01-01

Synthesizing the ideas of high-performance Human Resource Management (HRM), positive psychological capital, and componential theory of creativity, the present study develops a multi-level causal framework linking high-performance work practices (HPWP), positive psychological capital, employee creative performance behaviors and creative performance. The paper argues that to provide a convincing explanation of the association between HRM practices and creativity, we need to improve our theoreti...

Socioeconomic Position, Rural Residence, and Marginality Influences on Obesity Status in the Adult Mexican Population

OpenAIRE

Sparks, P. Johnelle; Sparks, Corey S.

2012-01-01

This paper assesses individual and social environment determinants of obesity in the adult Mexican population based on socioeconomic position, rural residence, and areal deprivation. Using a nationally representative health and nutrition survey, this analysis considers individual and structural determinants of obesity from a socioeconomic position and health disparities conceptual framework using multilevel logistic regression models. We find that more than thirty percent of Mexican adults we...

Nonresonant interaction of ultrashort electromagnetic pulses with multilevel quantum systems

Science.gov (United States)

Belenov, E.; Isakov, V.; Nazarkin, A.

1994-01-01

Some features of the excitation of multilevel quantum systems under the action of electromagnetic pulses which are shorter than the inverse frequency of interlevel transitions are considered. It is shown that the interaction is characterized by a specific type of selectivity which is not connected with the resonant absorption of radiation. The simplest three-level model displays the inverse population of upper levels. The effect of an ultrashort laser pulse on a multilevel molecule was regarded as an instant reception of the oscillation velocity by the oscillator and this approach showed an effective excitation and dissociation of the molecule. The estimations testify to the fact that these effects can be observed using modern femtosecond lasers.

An Airline-Based Multilevel Analysis of Airfare Elasticity for Passenger Demand

Science.gov (United States)

Castelli, Lorenzo; Ukovich, Walter; Pesenti, Raffaele

2003-01-01

Price elasticity of passenger demand for a specific airline is estimated. The main drivers affecting passenger demand for air transportation are identified. First, an Ordinary Least Squares regression analysis is performed. Then, a multilevel analysis-based methodology to investigate the pattern of variation of price elasticity of demand among the various routes of the airline under study is proposed. The experienced daily passenger demands on each fare-class are grouped for each considered route. 9 routes were studied for the months of February and May in years from 1999 to 2002, and two fare-classes were defined (business and economy). The analysis has revealed that the airfare elasticity of passenger demand significantly varies among the different routes of the airline.

The Differences between Multilevel Marketing and the Financial Pyramids or “Pyramid Scheme”

Directory of Open Access Journals (Sweden)

Vanessa Braga Santos

2017-06-01

Full Text Available This research aims to analyze and understand the difference between the concept of Multilevel Marketing and the Financial Pyramids. The main objective of this work is to clarify the differences between these two business models that are growing worldwide and also present concepts that show the success of professionals in this kind of new business model. Multilevel Marketing shows a sustainable system, a direct selling business that includes recruiting distributors with a profit share and also by recruiting new members. In the Financial Pyramid concept, the problem is that business support is the network itself, and often there are no products to be commercialized, so this model is unsustainable and considered as an illegal business in several countries, including Brazil. Within this approach, a case study was conducted with one of the largest Multilevel Marketing companies in the world, Mary Kay. We conducted a direct interview with one of Mary Kay Independent Sales Directors from the city of Piracicaba, held in October 2016, and collected data surveys from the internet. The markets today are based on moving products, so we concluded that Multilevel Marketing is a great business opportunity to make an extra income by marketing services and products.

Determinants of firms' investment behaviour : a multilevel approach

NARCIS (Netherlands)

Farla, K.

2013-01-01

This paper investigates micro and macro determinants of firms' investment behaviour using firm data from 101 developing and emerging economies. A substantial number of firms in our sample does not invest in fixed capital or invests little relative to sales revenue. Using a multilevel probit model we

Modular Multilevel Converter Control Strategy with Fault Tolerance

DEFF Research Database (Denmark)

Teodorescu, Remus; Eni, Emanuel-Petre; Mathe, Laszlo

2013-01-01

The Modular Multilevel Converter (MMC) technology has recently emerged in VSC-HVDC applications where it demonstrated higher efficiency and fault tolerance compared to the classical 2-level topology. Due to the ability of MMC to connect to HV levels, MMC can be also used in transformerless STATCOM...

All unitary ray representations of the conformal group SU(2,2) with positive energy

International Nuclear Information System (INIS)

Mack, G.

1975-12-01

We find all those unitary irreducible representations of the infinitely - sheeted covering group G tilde of the conformal group SU(2,2)/Z 4 which have positive energy P 0 >= O. They are all finite component field representations and are labelled by dimension d and a finite dimensional irreducible representation (j 1 , j 2 ) of the Lorentz group SL(2C). They all decompose into a finite number of unitary irreducible representations of the Poincare subgroup with dilations. (orig.) [de

Multilevel Hybrid Chernoff Tau-Leap

KAUST Repository

Moraes, Alvaro

2016-01-06

Markovian pure jump processes can model many phenomena, e.g. chemical reactions at molecular level, protein transcription and translation, spread of epidemics diseases in small populations and in wireless communication networks, among many others. In this work [6] we present a novel multilevel algorithm for the Chernoff-based hybrid tauleap algorithm. This variance reduction technique allows us to: (a) control the global exit probability of any simulated trajectory, (b) obtain accurate and computable estimates for the expected value of any smooth observable of the process with minimal computational work.

Multilevel Hybrid Chernoff Tau-Leap

KAUST Repository

Moraes, Alvaro

2015-01-07

Markovian pure jump processes can model many phenomena, e.g. chemical reactions at molecular level, protein transcription and translation, spread of epidemics diseases in small populations and in wireless communication networks, among many others. In this work [6] we present a novel multilevel algorithm for the Chernoff-based hybrid tauleap algorithm. This variance reduction technique allows us to: (a) control the global exit probability of any simulated trajectory, (b) obtain accurate and computable estimates for the expected value of any smooth observable of the process with minimal computational work.

Multilevel Hybrid Chernoff Tau-Leap

KAUST Repository

Moraes, Alvaro

2014-01-06

Markovian pure jump processes can model many phenomena, e.g. chemical reactions at molecular level, protein transcription and translation, spread of epidemics diseases in small populations and in wireless communication networks, among many others. In this work [6] we present a novel multilevel algorithm for the Chernoff-based hybrid tauleap algorithm. This variance reduction technique allows us to: (a) control the global exit probability of any simulated trajectory, (b) obtain accurate and computable estimates for the expected value of any smooth observable of the process with minimal computational work.

Multilevel resistive information storage and retrieval

Science.gov (United States)

Lohn, Andrew; Mickel, Patrick R.

2016-08-09

The present invention relates to resistive random-access memory (RRAM or ReRAM) systems, as well as methods of employing multiple state variables to form degenerate states in such memory systems. The methods herein allow for precise write and read steps to form multiple state variables, and these steps can be performed electrically. Such an approach allows for multilevel, high density memory systems with enhanced information storage capacity and simplified information retrieval.

Improved Bat Algorithm Applied to Multilevel Image Thresholding

Directory of Open Access Journals (Sweden)

Adis Alihodzic

2014-01-01

Full Text Available Multilevel image thresholding is a very important image processing technique that is used as a basis for image segmentation and further higher level processing. However, the required computational time for exhaustive search grows exponentially with the number of desired thresholds. Swarm intelligence metaheuristics are well known as successful and efficient optimization methods for intractable problems. In this paper, we adjusted one of the latest swarm intelligence algorithms, the bat algorithm, for the multilevel image thresholding problem. The results of testing on standard benchmark images show that the bat algorithm is comparable with other state-of-the-art algorithms. We improved standard bat algorithm, where our modifications add some elements from the differential evolution and from the artificial bee colony algorithm. Our new proposed improved bat algorithm proved to be better than five other state-of-the-art algorithms, improving quality of results in all cases and significantly improving convergence speed.

How does a servant leader fuel the service fire? A multilevel model of servant leadership, individual self identity, group competition climate, and customer service performance.

Science.gov (United States)

Chen, Zhijun; Zhu, Jing; Zhou, Mingjian

2015-03-01

Building on a social identity framework, our cross-level process model explains how a manager's servant leadership affects frontline employees' service performance, measured as service quality, customer-focused citizenship behavior, and customer-oriented prosocial behavior. Among a sample of 238 hairstylists in 30 salons and 470 of their customers, we found that hair stylists' self-identity embedded in the group, namely, self-efficacy and group identification, partially mediated the positive effect of salon managers' servant leadership on stylists' service performance as rated by the customers, after taking into account the positive influence of transformational leadership. Moreover, group competition climate strengthened the positive relationship between self-efficacy and service performance. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Using iMCFA to Perform the CFA, Multilevel CFA, and Maximum Model for Analyzing Complex Survey Data.

Science.gov (United States)

Wu, Jiun-Yu; Lee, Yuan-Hsuan; Lin, John J H

2018-01-01

To construct CFA, MCFA, and maximum MCFA with LISREL v.8 and below, we provide iMCFA (integrated Multilevel Confirmatory Analysis) to examine the potential multilevel factorial structure in the complex survey data. Modeling multilevel structure for complex survey data is complicated because building a multilevel model is not an infallible statistical strategy unless the hypothesized model is close to the real data structure. Methodologists have suggested using different modeling techniques to investigate potential multilevel structure of survey data. Using iMCFA, researchers can visually set the between- and within-level factorial structure to fit MCFA, CFA and/or MAX MCFA models for complex survey data. iMCFA can then yield between- and within-level variance-covariance matrices, calculate intraclass correlations, perform the analyses and generate the outputs for respective models. The summary of the analytical outputs from LISREL is gathered and tabulated for further model comparison and interpretation. iMCFA also provides LISREL syntax of different models for researchers' future use. An empirical and a simulated multilevel dataset with complex and simple structures in the within or between level was used to illustrate the usability and the effectiveness of the iMCFA procedure on analyzing complex survey data. The analytic results of iMCFA using Muthen's limited information estimator were compared with those of Mplus using Full Information Maximum Likelihood regarding the effectiveness of different estimation methods.

Effect of a Multi-Level Education Intervention Model on Knowledge and Attitudes of Accidental Injuries in Rural Children in Zunyi, Southwest China

Directory of Open Access Journals (Sweden)

Bo-Ling Cao

2015-04-01

Full Text Available Objective: To explore the effect of a school-family-individual (SFI multi-level education intervention model on knowledge and attitudes about accidental injuries among school-aged children to improve injury prevention strategies and reduce the incidence of pediatric injuries. Methods: The random sample of rural school-aged children were recruited by using a multistage, stratified, cluster sampling method in Zunyi, Southwest China from 2012 to 2014, and 2342 children were randomly divided into intervention and control groups. Then children answered a baseline survey to collect knowledge and attitude scores (KAS of accidental injuries. In the intervention group, children, their parents/guardians and the school received a SFI multi-level education intervention, which included a children’s injury-prevention poster at schools, an open letter about security instruction for parents/guardians and multiple-media health education (Microsoft PowerPoint lectures, videos, handbooks, etc. to children. Children in the control group were given only handbook education. After 16 months, children answered a follow-up survey to collect data on accidental injury types and accidental injury-related KAS for comparing the intervention and control groups and baseline and follow-up data. Results: The distribution of gender was not significantly different while age was different between the baseline and follow-up survey. At baseline, the mean KAS was lower for the intervention than control group (15.37 ± 3.40 and 18.35 ± 5.01; p < 0.001. At follow-up, the mean KAS was higher for the intervention than control group (21.16 ± 3.05 and 20.02 ± 3.40; p < 0.001. The increase in KAS in the intervention and control groups was significant (p < 0.001; KAS: 5.79 vs. 1.67 and suggested that children’s injury-related KAS improved in the intervention group. Moreover, the KAS between the groups differed for most subtypes of incidental injuries (based on International

Using multilevel modeling to assess case-mix adjusters in consumer experience surveys in health care.

Science.gov (United States)

Damman, Olga C; Stubbe, Janine H; Hendriks, Michelle; Arah, Onyebuchi A; Spreeuwenberg, Peter; Delnoij, Diana M J; Groenewegen, Peter P

2009-04-01

Ratings on the quality of healthcare from the consumer's perspective need to be adjusted for consumer characteristics to ensure fair and accurate comparisons between healthcare providers or health plans. Although multilevel analysis is already considered an appropriate method for analyzing healthcare performance data, it has rarely been used to assess case-mix adjustment of such data. The purpose of this article is to investigate whether multilevel regression analysis is a useful tool to detect case-mix adjusters in consumer assessment of healthcare. We used data on 11,539 consumers from 27 Dutch health plans, which were collected using the Dutch Consumer Quality Index health plan instrument. We conducted multilevel regression analyses of consumers' responses nested within health plans to assess the effects of consumer characteristics on consumer experience. We compared our findings to the results of another methodology: the impact factor approach, which combines the predictive effect of each case-mix variable with its heterogeneity across health plans. Both multilevel regression and impact factor analyses showed that age and education were the most important case-mix adjusters for consumer experience and ratings of health plans. With the exception of age, case-mix adjustment had little impact on the ranking of health plans. On both theoretical and practical grounds, multilevel modeling is useful for adequate case-mix adjustment and analysis of performance ratings.

Multilevel summation methods for efficient evaluation of long-range pairwise interactions in atomistic and coarse-grained molecular simulation.

Energy Technology Data Exchange (ETDEWEB)

Bond, Stephen D.

2014-01-01

The availability of efficient algorithms for long-range pairwise interactions is central to the success of numerous applications, ranging in scale from atomic-level modeling of materials to astrophysics. This report focuses on the implementation and analysis of the multilevel summation method for approximating long-range pairwise interactions. The computational cost of the multilevel summation method is proportional to the number of particles, N, which is an improvement over FFTbased methods whos cost is asymptotically proportional to N logN. In addition to approximating electrostatic forces, the multilevel summation method can be use to efficiently approximate convolutions with long-range kernels. As an application, we apply the multilevel summation method to a discretized integral equation formulation of the regularized generalized Poisson equation. Numerical results are presented using an implementation of the multilevel summation method in the LAMMPS software package. Preliminary results show that the computational cost of the method scales as expected, but there is still a need for further optimization.

Effectiveness of Positive Group Psychotherapy on Resiliency, Happiness and General Health on Women with a Substance Dependence Spouses

Directory of Open Access Journals (Sweden)

F sohrabi

2016-03-01

Full Text Available The aim of this study was to evaluate the effectiveness of positive group psychotherapy on resiliency, happiness and general health in Women with substance dependent spouse. The research design was quasi - experimental with pre-test, post-test and one-month follow - up with the control group. The sample was comprised of women whom their spouse were referred to addiction clinic. Twenty - four women were selected and randomly assigned to experimental and control groups. Both groups were assessed by Davidson Resilience Scale, Peterson happiness directions questionnaires and General Health Questionnaire (GHQ. Positive group psychotherapy was conducted on the experimental group for 14 sessions, each session lasting 90- minutes. The data was analyzed with ANCOVA. The findings indicated that the mean scores of post-test in the experimental groups on resilience, happiness, and public health, was significantly higher than the mean scores of post-test in control group. Benferroni test was indicating the stable effect of therapy. According to the findings, it can be said that group positive psychotherapy was effective in promoting resiliency, happiness, and general health of women with the dependent drug spouses.

Extending the enterprise through multi-level supply control

NARCIS (Netherlands)

Vlist, van der P.; Hoppenbrouwers, J.J.E.M.; Hegge, H.M.H.

1997-01-01

Demands for flexibility require larger parts of the supply chain to become customer driven. This article describes multi-level supply control (MLSC) as a mechanism to facilitate that; it allows to specify gradually and thus to shift the customer order decoupling point well across the boundary to the

Local posterior concentration rate for multilevel sparse sequences

NARCIS (Netherlands)

Belitser, E.N.; Nurushev, N.

2017-01-01

We consider empirical Bayesian inference in the many normal means model in the situation when the high-dimensional mean vector is multilevel sparse, that is,most of the entries of the parameter vector are some fixed values. For instance, the traditional sparse signal is a particular case (with one

Need for Cognition and Active Information Search in Small Student Groups

Science.gov (United States)

Curseu, Petru Lucian

2011-01-01

In a sample of 213 students organized in 44 groups this study tests the impact of need for cognition on active information search by using a multilevel analysis. The results show that group members with high need for cognition seek more advice in task related issues than those with low need for cognition and this pattern of information exchange is…

A multilevel structural equation modeling analysis of vulnerabilities and resilience resources influencing affective adaptation to chronic pain.

Science.gov (United States)

Sturgeon, John A; Zautra, Alex J; Arewasikporn, Anne

2014-02-01

The processes of individual adaptation to chronic pain are complex and occur across multiple domains. We examined the social, cognitive, and affective context of daily pain adaptation in individuals with fibromyalgia and osteoarthritis. By using a sample of 260 women with fibromyalgia or osteoarthritis, we examined the contributions of pain catastrophizing, negative interpersonal events, and positive interpersonal events to daily negative and positive affect across 30days of daily diary data. Individual differences and daily fluctuations in predictor variables were estimated simultaneously by utilizing multilevel structural equation modeling techniques. The relationships between pain and negative and positive affect were mediated by stable and day-to-day levels of pain catastrophizing as well as day-to-day positive interpersonal events, but not negative interpersonal events. There were significant and independent contributions of pain catastrophizing and positive interpersonal events to adaptation to pain and pain-related affective dysregulation. These effects occur both between persons and within a person's everyday life. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Job demands, burnout, and engagement among nurses: A multi-level analysis of ORCAB data investigating the moderating effect of teamwork

Science.gov (United States)

Montgomery, Anthony; Spânu, Florina; Băban, Adriana; Panagopoulou, Efharis

2015-01-01

According to the Job Demands-Resources (JD-R) model, burnout and engagement are psychological reactions that develop when individual characteristics interact with work characteristics. This study tests the JD-R model using multilevel analysis to test the main and moderating effects of teamwork effectiveness among 1156 nurses in 93 departments from seven European countries. Workload, emotional and organizational demands were positively associated with emotional exhaustion, depersonalization, and negatively with vigor. Emotional and organizational demands were negatively associated with dedication. Teamwork effectiveness was positively associated with engagement. We found no evidence for the moderating effect of teamwork effectiveness in reducing individual perceptions of demands. PMID:26877971

Multilevel compression of random walks on networks reveals hierarchical organization in large integrated systems.

Directory of Open Access Journals (Sweden)

Martin Rosvall

Full Text Available To comprehend the hierarchical organization of large integrated systems, we introduce the hierarchical map equation, which reveals multilevel structures in networks. In this information-theoretic approach, we exploit the duality between compression and pattern detection; by compressing a description of a random walker as a proxy for real flow on a network, we find regularities in the network that induce this system-wide flow. Finding the shortest multilevel description of the random walker therefore gives us the best hierarchical clustering of the network--the optimal number of levels and modular partition at each level--with respect to the dynamics on the network. With a novel search algorithm, we extract and illustrate the rich multilevel organization of several large social and biological networks. For example, from the global air traffic network we uncover countries and continents, and from the pattern of scientific communication we reveal more than 100 scientific fields organized in four major disciplines: life sciences, physical sciences, ecology and earth sciences, and social sciences. In general, we find shallow hierarchical structures in globally interconnected systems, such as neural networks, and rich multilevel organizations in systems with highly separated regions, such as road networks.

Just how multi-level is leadership research? : A document co-citation analysis 1980–2013 on leadership constructs and outcomes

NARCIS (Netherlands)

Batistic, S.; Cerne, Matej; Vogel, Bernd

2017-01-01

The use of multi-level theories and methodologies in leadership has gained momentum in recent years. However, the leadership field still suffers from a fragmented and unclear evolution and practice of multi-level approaches. The questions of how and to what extent multi-level research has evolved in

Predicting Psychotherapy Dropouts: A Multilevel Approach.

Science.gov (United States)

Kegel, Alexander F; Flückiger, Christoph

2015-01-01

The role of therapeutic processes in predicting premature termination of psychotherapy has been a particular focus of recent research. The purpose of this study was to contrast outpatients who completed therapy and those who dropped out with respect to their self-reported in-session experiences of self-esteem, mastery, clarification and the therapeutic alliance. The 296 patients with mixed disorders were treated with an integrative form of cognitive-behavioural therapy without pre-determined time limit (M = 20.2 sessions). Multilevel analyses indicated that patients who did not completetreatment reported, on average, lower levels of self-esteem, mastery and clarification and lower ratings of their therapeutic alliance in treatment in contrast to patients who completed therapy. Patient-reported change in self-esteem experiences over the course of treatment turned out to be the strongest predictor of dropout from psychotherapy or successful completion. When dropout occurred before the average treatment length was reached, patients reported fewer clarifying experiences as early as the first session and their ratings of the therapeutic alliance were characterized by an absence of positive development. Both of these aspects seem to be involved in patients' decisions to leave treatment early. The findings underscore the importance of the therapeutic process in understanding the mechanisms behind treatment dropout. Analyses data from 296 patients at a private outpatient clinic in a routine practice setting (CBT). Completer/dropout definition: presence or absence of measurement battery at post-assessment. Focuses on change in therapy processes by investigating post-session reports. Finds that positive changes in self-esteem experiences is the most robust predictor of dropout, followed by ratings of clarification experiences and the global alliance. In line with recent dropout research, these process indicators might help to detect therapeutic situations that are

On the multi-level solution algorithm for Markov chains

Energy Technology Data Exchange (ETDEWEB)

Horton, G. [Univ. of Erlangen, Nuernberg (Germany)

1996-12-31

We discuss the recently introduced multi-level algorithm for the steady-state solution of Markov chains. The method is based on the aggregation principle, which is well established in the literature. Recursive application of the aggregation yields a multi-level method which has been shown experimentally to give results significantly faster than the methods currently in use. The algorithm can be reformulated as an algebraic multigrid scheme of Galerkin-full approximation type. The uniqueness of the scheme stems from its solution-dependent prolongation operator which permits significant computational savings in the evaluation of certain terms. This paper describes the modeling of computer systems to derive information on performance, measured typically as job throughput or component utilization, and availability, defined as the proportion of time a system is able to perform a certain function in the presence of component failures and possibly also repairs.

Human cooperation by lethal group competition.

Science.gov (United States)

Egas, Martijn; Kats, Ralph; van der Sar, Xander; Reuben, Ernesto; Sabelis, Maurice W

2013-01-01

Why humans are prone to cooperate puzzles biologists, psychologists and economists alike. Between-group conflict has been hypothesized to drive within-group cooperation. However, such conflicts did not have lasting effects in laboratory experiments, because they were about luxury goods, not needed for survival ("looting"). Here, we find within-group cooperation to last when between-group conflict is implemented as "all-out war" (eliminating the weakest groups). Human subjects invested in helping group members to avoid having the lowest collective pay-off, whereas they failed to cooperate in control treatments with random group elimination or with no subdivision in groups. When the game was repeated, experience was found to promote helping. Thus, not within-group interactions alone, not random group elimination, but pay-off-dependent group elimination was found to drive within-group cooperation in our experiment. We suggest that some forms of human cooperation are maintained by multi-level selection: reciprocity within groups and lethal competition among groups acting together.

Multidisciplinary design and analytic approaches to advance prospective research on the multilevel determinants of child health.

Science.gov (United States)

Johnson, Sara B; Little, Todd D; Masyn, Katherine; Mehta, Paras D; Ghazarian, Sharon R

2017-06-01

Characterizing the determinants of child health and development over time, and identifying the mechanisms by which these determinants operate, is a research priority. The growth of precision medicine has increased awareness and refinement of conceptual frameworks, data management systems, and analytic methods for multilevel data. This article reviews key methodological challenges in cohort studies designed to investigate multilevel influences on child health and strategies to address them. We review and summarize methodological challenges that could undermine prospective studies of the multilevel determinants of child health and ways to address them, borrowing approaches from the social and behavioral sciences. Nested data, variation in intervals of data collection and assessment, missing data, construct measurement across development and reporters, and unobserved population heterogeneity pose challenges in prospective multilevel cohort studies with children. We discuss innovations in missing data, innovations in person-oriented analyses, and innovations in multilevel modeling to address these challenges. Study design and analytic approaches that facilitate the integration across multiple levels, and that account for changes in people and the multiple, dynamic, nested systems in which they participate over time, are crucial to fully realize the promise of precision medicine for children and adolescents. Copyright © 2017 Elsevier Inc. All rights reserved.

The Influence of Forums and Multilevel Governance on the Climate Adaptation Practices of Australian Organizations

Directory of Open Access Journals (Sweden)

Lorraine E. Bates

2013-12-01

Full Text Available To date, there are few regulations and policies relating to climate change in Australia. Uncertainty about the timing, structure, and potential impact of proposed legislation such as a national carbon abatement scheme, is leading to planning delays across the country. To assist with these policy uncertainties, organizations can embed themselves in multilevel governance frameworks that inform, structure, and facilitate strategic development, planning, and action. As part of these networks, organizational representatives also engage in formal and informal forums, a type of interorganizational relationship, which can include industry task forces, policy development committees, interagency groups, and specific climate change committees. Forums constitute an additional level of governance that influences decision making. The patterns of relationships within these multilevel governance frameworks are examined in this paper, with a focus on the forum level of organizational cooperation. Specifically, we investigate the type of forums operating and their role in supporting organizational responses to climate change. A series of interviews and focus groups were conducted in two study areas, the Swan Canning region of Western Australia and the Hunter / Central Coast region of New South Wales. The results indicate that organizations participate in a diverse range of forums. Further, forums appear to play a key role in the everyday business of organizations by enhancing their ability to plan and address a range of issues, including those associated with climate change. In addition the research highlights some of the barriers and drivers for the development and implementation of climate adaptation practices that emerge from forum discussions. For example, a lack of government guidance in interpreting climate change policy was described as a barrier yet access to the knowledge and expertise of participants was highlighted as a potential driver. The paper

A DC-Link Voltage Self-Balance Method for a Diode-Clamped Modular Multilevel Converter With Minimum Number of Voltage Sensors

DEFF Research Database (Denmark)

Gao, Congzhe; Jiang, Xinjian; Li, Yongdong

2013-01-01

Voltage balance issue of dc-link capacitors is very important for applications of a cascade multilevel converter or a modular multilevel converter. In this paper, a novel diode-clamped modular multilevel converter (DCM2C) topology is proposed and a power feedback control method is developed...... used traditional method; therefore, the system performance improvement and cost reduction are expected. Based on the proposed DCM2C, a novel N +1-level cascade multilevel topology is proposed for a cascade active power filter (CS-APF). The simulation and experimental results from the CS-APF have...

Multi-level approach for parametric roll analysis

Science.gov (United States)

Kim, Taeyoung; Kim, Yonghwan

2011-03-01

The present study considers multi-level approach for the analysis of parametric roll phenomena. Three kinds of computation method, GM variation, impulse response function (IRF), and Rankine panel method, are applied for the multi-level approach. IRF and Rankine panel method are based on the weakly nonlinear formulation which includes nonlinear Froude- Krylov and restoring forces. In the computation result of parametric roll occurrence test in regular waves, IRF and Rankine panel method show similar tendency. Although the GM variation approach predicts the occurrence of parametric roll at twice roll natural frequency, its frequency criteria shows a little difference. Nonlinear roll motion in bichromatic wave is also considered in this study. To prove the unstable roll motion in bichromatic waves, theoretical and numerical approaches are applied. The occurrence of parametric roll is theoretically examined by introducing the quasi-periodic Mathieu equation. Instability criteria are well predicted from stability analysis in theoretical approach. From the Fourier analysis, it has been verified that difference-frequency effects create the unstable roll motion. The occurrence of unstable roll motion in bichromatic wave is also observed in the experiment.

Plasma simulation studies using multilevel physics models

International Nuclear Information System (INIS)

Park, W.; Belova, E.V.; Fu, G.Y.; Tang, X.Z.; Strauss, H.R.; Sugiyama, L.E.

1999-01-01

The question of how to proceed toward ever more realistic plasma simulation studies using ever increasing computing power is addressed. The answer presented here is the M3D (Multilevel 3D) project, which has developed a code package with a hierarchy of physics levels that resolve increasingly complete subsets of phase-spaces and are thus increasingly more realistic. The rationale for the multilevel physics models is given. Each physics level is described and examples of its application are given. The existing physics levels are fluid models (3D configuration space), namely magnetohydrodynamic (MHD) and two-fluids; and hybrid models, namely gyrokinetic-energetic-particle/MHD (5D energetic particle phase-space), gyrokinetic-particle-ion/fluid-electron (5D ion phase-space), and full-kinetic-particle-ion/fluid-electron level (6D ion phase-space). Resolving electron phase-space (5D or 6D) remains a future project. Phase-space-fluid models are not used in favor of δf particle models. A practical and accurate nonlinear fluid closure for noncollisional plasmas seems not likely in the near future. copyright 1999 American Institute of Physics

A collision dynamics model of a multi-level train

Science.gov (United States)

2006-11-05

In train collisions, multi-level rail passenger vehicles can deform in modes that are different from the behavior of single level cars. The deformation in single level cars usually occurs at the front end during a collision. In one particular inciden...

The Effects of Autonomy and Empowerment on Employee Turnover: Test of a Multilevel Model in Teams

Science.gov (United States)

Liu, Dong; Zhang, Shu; Wang, Lei; Lee, Thomas W.

2011-01-01

Extending research on voluntary turnover in the team setting, this study adopts a multilevel self-determination theoretical approach to examine the unique roles of individual and social-contextual motivational precursors, autonomy orientation and autonomy support, in reducing team member voluntary turnover. Analysis of multilevel time-lagged data…

Multilevel joint competing risk models

Science.gov (United States)

Karunarathna, G. H. S.; Sooriyarachchi, M. R.

2017-09-01

Joint modeling approaches are often encountered for different outcomes of competing risk time to event and count in many biomedical and epidemiology studies in the presence of cluster effect. Hospital length of stay (LOS) has been the widely used outcome measure in hospital utilization due to the benchmark measurement for measuring multiple terminations such as discharge, transferred, dead and patients who have not completed the event of interest at the follow up period (censored) during hospitalizations. Competing risk models provide a method of addressing such multiple destinations since classical time to event models yield biased results when there are multiple events. In this study, the concept of joint modeling has been applied to the dengue epidemiology in Sri Lanka, 2006-2008 to assess the relationship between different outcomes of LOS and platelet count of dengue patients with the district cluster effect. Two key approaches have been applied to build up the joint scenario. In the first approach, modeling each competing risk separately using the binary logistic model, treating all other events as censored under the multilevel discrete time to event model, while the platelet counts are assumed to follow a lognormal regression model. The second approach is based on the endogeneity effect in the multilevel competing risks and count model. Model parameters were estimated using maximum likelihood based on the Laplace approximation. Moreover, the study reveals that joint modeling approach yield more precise results compared to fitting two separate univariate models, in terms of AIC (Akaike Information Criterion).

Dispersion Tolerance of 40 Gbaud Multilevel Modulation Formats with up to 3 bits per Symbol

DEFF Research Database (Denmark)

Jensen, Jesper Bevensee; Tokle, Torger; Geng, Yan

2006-01-01

We present numerical and experimental investigations of dispersion tolerance for multilevel phase- and amplitude modulation with up to 3 bits per symbol at a symbol rate of 40 Gbaud......We present numerical and experimental investigations of dispersion tolerance for multilevel phase- and amplitude modulation with up to 3 bits per symbol at a symbol rate of 40 Gbaud...

Multilevel summation with B-spline interpolation for pairwise interactions in molecular dynamics simulations

International Nuclear Information System (INIS)

Hardy, David J.; Schulten, Klaus; Wolff, Matthew A.; Skeel, Robert D.; Xia, Jianlin

2016-01-01

The multilevel summation method for calculating electrostatic interactions in molecular dynamics simulations constructs an approximation to a pairwise interaction kernel and its gradient, which can be evaluated at a cost that scales linearly with the number of atoms. The method smoothly splits the kernel into a sum of partial kernels of increasing range and decreasing variability with the longer-range parts interpolated from grids of increasing coarseness. Multilevel summation is especially appropriate in the context of dynamics and minimization, because it can produce continuous gradients. This article explores the use of B-splines to increase the accuracy of the multilevel summation method (for nonperiodic boundaries) without incurring additional computation other than a preprocessing step (whose cost also scales linearly). To obtain accurate results efficiently involves technical difficulties, which are overcome by a novel preprocessing algorithm. Numerical experiments demonstrate that the resulting method offers substantial improvements in accuracy and that its performance is competitive with an implementation of the fast multipole method in general and markedly better for Hamiltonian formulations of molecular dynamics. The improvement is great enough to establish multilevel summation as a serious contender for calculating pairwise interactions in molecular dynamics simulations. In particular, the method appears to be uniquely capable for molecular dynamics in two situations, nonperiodic boundary conditions and massively parallel computation, where the fast Fourier transform employed in the particle–mesh Ewald method falls short.

Area-level poverty and preterm birth risk: A population-based multilevel analysis

Science.gov (United States)

DeFranco, Emily A; Lian, Min; Muglia, Louis A; Schootman, Mario

2008-01-01

Background Preterm birth is a complex disease with etiologic influences from a variety of social, environmental, hormonal, genetic, and other factors. The purpose of this study was to utilize a large population-based birth registry to estimate the independent effect of county-level poverty on preterm birth risk. To accomplish this, we used a multilevel logistic regression approach to account for multiple co-existent individual-level variables and county-level poverty rate. Methods Population-based study utilizing Missouri's birth certificate database (1989–1997). We conducted a multilevel logistic regression analysis to estimate the effect of county-level poverty on PTB risk. Of 634,994 births nested within 115 counties in Missouri, two levels were considered. Individual-level variables included demographics factors, prenatal care, health-related behavioral risk factors, and medical risk factors. The area-level variable included the percentage of the population within each county living below the poverty line (US census data, 1990). Counties were divided into quartiles of poverty; the first quartile (lowest rate of poverty) was the reference group. Results PTB rate of PTB poverty and increased through the 4th quartile (4.9%), p poverty was significantly associated with PTB risk. PTB risk (poverty, adjusted odds ratio (adjOR) 1.18 (95% CI 1.03, 1.35), with a similar effect at earlier gestational ages (birth, above other underlying risk factors. Although the risk increase is modest, it affects a large number of pregnancies. PMID:18793437

Area-level poverty and preterm birth risk: A population-based multilevel analysis

Directory of Open Access Journals (Sweden)

Muglia Louis A

2008-09-01

Full Text Available Abstract Background Preterm birth is a complex disease with etiologic influences from a variety of social, environmental, hormonal, genetic, and other factors. The purpose of this study was to utilize a large population-based birth registry to estimate the independent effect of county-level poverty on preterm birth risk. To accomplish this, we used a multilevel logistic regression approach to account for multiple co-existent individual-level variables and county-level poverty rate. Methods Population-based study utilizing Missouri's birth certificate database (1989–1997. We conducted a multilevel logistic regression analysis to estimate the effect of county-level poverty on PTB risk. Of 634,994 births nested within 115 counties in Missouri, two levels were considered. Individual-level variables included demographics factors, prenatal care, health-related behavioral risk factors, and medical risk factors. The area-level variable included the percentage of the population within each county living below the poverty line (US census data, 1990. Counties were divided into quartiles of poverty; the first quartile (lowest rate of poverty was the reference group. Results PTB th quartile (4.9%, p adjOR 1.18 (95% CI 1.03, 1.35, with a similar effect at earlier gestational ages (adjOR 1.27 (95% CI 1.06, 1.52. Conclusion Women residing in socioeconomically deprived areas are at increased risk of preterm birth, above other underlying risk factors. Although the risk increase is modest, it affects a large number of pregnancies.

Customized binary and multi-level HfO2-x-based memristors tuned by oxidation conditions.

Science.gov (United States)

He, Weifan; Sun, Huajun; Zhou, Yaxiong; Lu, Ke; Xue, Kanhao; Miao, Xiangshui

2017-08-30

The memristor is a promising candidate for the next generation non-volatile memory, especially based on HfO 2-x , given its compatibility with advanced CMOS technologies. Although various resistive transitions were reported independently, customized binary and multi-level memristors in unified HfO 2-x material have not been studied. Here we report Pt/HfO 2-x /Ti memristors with double memristive modes, forming-free and low operation voltage, which were tuned by oxidation conditions of HfO 2-x films. As O/Hf ratios of HfO 2-x films increase, the forming voltages, SET voltages, and R off /R on windows increase regularly while their resistive transitions undergo from gradually to sharply in I/V sweep. Two memristors with typical resistive transitions were studied to customize binary and multi-level memristive modes, respectively. For binary mode, high-speed switching with 10 3 pulses (10 ns) and retention test at 85 °C (>10 4 s) were achieved. For multi-level mode, the 12-levels stable resistance states were confirmed by ongoing multi-window switching (ranging from 10 ns to 1 μs and completing 10 cycles of each pulse). Our customized binary and multi-level HfO 2-x -based memristors show high-speed switching, multi-level storage and excellent stability, which can be separately applied to logic computing and neuromorphic computing, further suitable for in-memory computing chip when deposition atmosphere may be fine-tuned.

Multilevel Factor Structure and Concurrent Validity of the Teacher Version of the Authoritative School Climate Survey.

Science.gov (United States)

Huang, Francis L; Cornell, Dewey G; Konold, Timothy; Meyer, Joseph P; Lacey, Anna; Nekvasil, Erin K; Heilbrun, Anna; Shukla, Kathan D

2015-12-01

School climate is well recognized as an important influence on student behavior and adjustment to school, but there is a need for theory-guided measures that make use of teacher perspectives. Authoritative school climate theory hypothesizes that a positive school climate is characterized by high levels of disciplinary structure and student support. A teacher version of the Authoritative School Climate Survey (ASCS) was administered to a statewide sample of 9099 7th- and 8th-grade teachers from 366 schools. The study used exploratory and multilevel confirmatory factor analyses (MCFA) that accounted for the nested data structure and allowed for the modeling of the factor structures at 2 levels. Multilevel confirmatory factor analyses conducted on both an exploratory (N = 4422) and a confirmatory sample (N = 4677) showed good support for the factor structures investigated. Factor correlations at 2 levels indicated that schools with greater levels of disciplinary structure and student support had higher student engagement, less teasing and bullying, and lower student aggression toward teachers. The teacher version of the ASCS can be used to assess 2 key domains of school climate and associated measures of student engagement and aggression toward peers and teachers. © 2015, American School Health Association.

Multivariate sparse group lasso for the multivariate multiple linear regression with an arbitrary group structure.

Science.gov (United States)

Li, Yanming; Nan, Bin; Zhu, Ji

2015-06-01

We propose a multivariate sparse group lasso variable selection and estimation method for data with high-dimensional predictors as well as high-dimensional response variables. The method is carried out through a penalized multivariate multiple linear regression model with an arbitrary group structure for the regression coefficient matrix. It suits many biology studies well in detecting associations between multiple traits and multiple predictors, with each trait and each predictor embedded in some biological functional groups such as genes, pathways or brain regions. The method is able to effectively remove unimportant groups as well as unimportant individual coefficients within important groups, particularly for large p small n problems, and is flexible in handling various complex group structures such as overlapping or nested or multilevel hierarchical structures. The method is evaluated through extensive simulations with comparisons to the conventional lasso and group lasso methods, and is applied to an eQTL association study. © 2015, The International Biometric Society.

Identifying Multilevel Barriers to Tobacco Intervention in Postdoctoral Dental Education.

Science.gov (United States)

Albert, David A; Bruzelius, Emilie; Ward, Angela; Gordon, Judith S

2016-04-01

The aims of this mixed-methods study were to assess tobacco treatment behaviors among residents and faculty in dental specialty postdoctoral programs and to explore factors in training and practice related to tobacco treatment education. Surveys and focus groups were conducted with a convenience sample of participants at three postdoctoral residency programs in New York City. Surveys assessed tobacco cessation training and behaviors. Focus groups explored barriers to implementing tobacco cessation treatment in educational settings. Data were collected between May and December 2013. Among the 160 faculty and residents identified as potentially eligible for the study, 60 were invited by program directors to participate, and 50 subsequently completed the survey and participated in a focus group (response rate of 31.3%). Survey results indicated high levels of asking patients about tobacco use and advising patients to quit. In contrast, specific tobacco cessation assistance and follow-up care occurred less frequently. There were statistically significant differences in tobacco cessation intervention across the specialties surveyed, but not between residents and faculty. Focus group comments were grouped into three broad areas: clinician factors, organizational support, and structural and contextual factors. Focus group results indicated that participants experienced significant organizational and structural barriers to learning about and providing tobacco treatment. Participants from each specialty indicated that multi-level barriers impeded their provision of evidence-based tobacco cessation interventions in postdoctoral educational settings. They suggested that didactic education should be reinforced by organizational- and systems-level changes to facilitate comprehensive tobacco education and effective cessation treatment in future dental practice.

Positive-definite functions and unitary representations of locally compact groups in a Hilbert space

International Nuclear Information System (INIS)

Gali, I.M.; Okb el-Bab, A.S.; Hassan, H.M.

1977-08-01

It is proved that the necessary and sufficient condition for the existence of an integral representation of a group of unitary operators in a Hilbert space is that it is positive-definite and continuous in some topology

Multilevel component analysis of time-resolved metabolic fingerprinting data

NARCIS (Netherlands)

Jansen, J.J.; Hoefsloot, H.C.J.; Greef, J. van der; Timmerman, M.E.; Smilde, A.K.

2005-01-01

Genomics-based technologies in systems biology have gained a lot of popularity in recent years. These technologies generate large amounts of data. To obtain information from this data, multivariate data analysis methods are required. Many of the datasets generated in genomics are multilevel

Outline of a multilevel approach of the network society

NARCIS (Netherlands)

van Dijk, Johannes A.G.M.

2005-01-01

Social and media networks, the Internet in particular, increasingly link interpersonal, organizational and mass communication. It is argued that this gives a cause for an interdisciplinary and multilevel approach of the network society. This will have to link traditional micro- and meso-level

Improved Multilevel Fast Multipole Method for Higher-Order discretizations

DEFF Research Database (Denmark)

Borries, Oscar Peter; Meincke, Peter; Jorgensen, Erik

2014-01-01

The Multilevel Fast Multipole Method (MLFMM) allows for a reduced computational complexity when solving electromagnetic scattering problems. Combining this with the reduced number of unknowns provided by Higher-Order discretizations has proven to be a difficult task, with the general conclusion b...

Individual and group antecedents of job satisfaction: a one-lab multilevel study

Directory of Open Access Journals (Sweden)

Isabel M. Martínez

Full Text Available This study examines the simultaneous effect of individual (selfefficacy and group variables (cohesion and gender diversity on satisfaction. A laboratory study was conducted involving 373 college students randomly distributed across 79 small groups, who performed a laboratory task in about five hours. Two-level Hierarchical Linear Modeling (HLM method was used. Results show the main effect from individual selfefficacy to satisfaction (both level 1, the cross-level effect from group cohesion (level 2 to individual satisfaction (level 1, and the interaction effect between self-efficacy and gender diversity to satisfaction. These results suggest that in a work group, satisfaction has a background in individual and group variables. Group cohesion and gender diversity have important effects on satisfaction. The article concludes with practical strategies and with limitations and suggestions for future research.

Can we get some cooperation around here? The mediating role of group norms on the relationship between team personality and individual helping behaviors.

Science.gov (United States)

Gonzalez-Mulé, Erik; DeGeest, David S; McCormick, Brian W; Seong, Jee Young; Brown, Kenneth G

2014-09-01

Drawing on the group-norms theory of organizational citizenship behaviors and person-environment fit theory, we introduce and test a multilevel model of the effects of additive and dispersion composition models of team members' personality characteristics on group norms and individual helping behaviors. Our model was tested using regression and random coefficients modeling on 102 research and development teams. Results indicated that high mean levels of extraversion are positively related to individual helping behaviors through the mediating effect of cooperative group norms. Further, low variance on agreeableness (supplementary fit) and high variance on extraversion (complementary fit) promote the enactment of individual helping behaviors, but only the effects of extraversion were mediated by cooperative group norms. Implications of these findings for theories of helping behaviors in teams are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

An introduction to multilevel flow modeling

DEFF Research Database (Denmark)

Lind, Morten

2011-01-01

Multilevel Flow Modeling (MFM) is a methodology for functional modeling of industrial processes on several interconnected levels of means-end and part-whole abstractions. The basic idea of MFM is to represent an industrial plant as a system which provides the means required to serve purposes in i...... in detail by a water mill example. The overall reasoning capabilities of MFM and its basis in cause-effect relations are also explained. The appendix contains an overview of MFM concepts and their definitions....

Evaluating Technical Efficiency of Nursing Care Using Data Envelopment Analysis and Multilevel Modeling.

Science.gov (United States)

Min, Ari; Park, Chang Gi; Scott, Linda D

2016-05-23

Data envelopment analysis (DEA) is an advantageous non-parametric technique for evaluating relative efficiency of performance. This article describes use of DEA to estimate technical efficiency of nursing care and demonstrates the benefits of using multilevel modeling to identify characteristics of efficient facilities in the second stage of analysis. Data were drawn from LTCFocUS.org, a secondary database including nursing home data from the Online Survey Certification and Reporting System and Minimum Data Set. In this example, 2,267 non-hospital-based nursing homes were evaluated. Use of DEA with nurse staffing levels as inputs and quality of care as outputs allowed estimation of the relative technical efficiency of nursing care in these facilities. In the second stage, multilevel modeling was applied to identify organizational factors contributing to technical efficiency. Use of multilevel modeling avoided biased estimation of findings for nested data and provided comprehensive information on differences in technical efficiency among counties and states. © The Author(s) 2016.

Multilevel Weighted Support Vector Machine for Classification on Healthcare Data with Missing Values.

Directory of Open Access Journals (Sweden)

Talayeh Razzaghi

Full Text Available This work is motivated by the needs of predictive analytics on healthcare data as represented by Electronic Medical Records. Such data is invariably problematic: noisy, with missing entries, with imbalance in classes of interests, leading to serious bias in predictive modeling. Since standard data mining methods often produce poor performance measures, we argue for development of specialized techniques of data-preprocessing and classification. In this paper, we propose a new method to simultaneously classify large datasets and reduce the effects of missing values. It is based on a multilevel framework of the cost-sensitive SVM and the expected maximization imputation method for missing values, which relies on iterated regression analyses. We compare classification results of multilevel SVM-based algorithms on public benchmark datasets with imbalanced classes and missing values as well as real data in health applications, and show that our multilevel SVM-based method produces fast, and more accurate and robust classification results.

Optical image encryption using QR code and multilevel fingerprints in gyrator transform domains

Science.gov (United States)

Wei, Yang; Yan, Aimin; Dong, Jiabin; Hu, Zhijuan; Zhang, Jingtao

2017-11-01

A new concept of GT encryption scheme is proposed in this paper. We present a novel optical image encryption method by using quick response (QR) code and multilevel fingerprint keys in gyrator transform (GT) domains. In this method, an original image is firstly transformed into a QR code, which is placed in the input plane of cascaded GTs. Subsequently, the QR code is encrypted into the cipher-text by using multilevel fingerprint keys. The original image can be obtained easily by reading the high-quality retrieved QR code with hand-held devices. The main parameters used as private keys are GTs' rotation angles and multilevel fingerprints. Biometrics and cryptography are integrated with each other to improve data security. Numerical simulations are performed to demonstrate the validity and feasibility of the proposed encryption scheme. In the future, the method of applying QR codes and fingerprints in GT domains possesses much potential for information security.

Enabling multi-level relevance feedback on PubMed by integrating rank learning into DBMS.

Science.gov (United States)

Yu, Hwanjo; Kim, Taehoon; Oh, Jinoh; Ko, Ilhwan; Kim, Sungchul; Han, Wook-Shin

2010-04-16

Finding relevant articles from PubMed is challenging because it is hard to express the user's specific intention in the given query interface, and a keyword query typically retrieves a large number of results. Researchers have applied machine learning techniques to find relevant articles by ranking the articles according to the learned relevance function. However, the process of learning and ranking is usually done offline without integrated with the keyword queries, and the users have to provide a large amount of training documents to get a reasonable learning accuracy. This paper proposes a novel multi-level relevance feedback system for PubMed, called RefMed, which supports both ad-hoc keyword queries and a multi-level relevance feedback in real time on PubMed. RefMed supports a multi-level relevance feedback by using the RankSVM as the learning method, and thus it achieves higher accuracy with less feedback. RefMed "tightly" integrates the RankSVM into RDBMS to support both keyword queries and the multi-level relevance feedback in real time; the tight coupling of the RankSVM and DBMS substantially improves the processing time. An efficient parameter selection method for the RankSVM is also proposed, which tunes the RankSVM parameter without performing validation. Thereby, RefMed achieves a high learning accuracy in real time without performing a validation process. RefMed is accessible at http://dm.postech.ac.kr/refmed. RefMed is the first multi-level relevance feedback system for PubMed, which achieves a high accuracy with less feedback. It effectively learns an accurate relevance function from the user's feedback and efficiently processes the function to return relevant articles in real time.

Who is the competent physics student? A study of students' positions and social interaction in small-group discussions

Science.gov (United States)

Due, Karin

2014-06-01

This article describes a study which explored the social interaction and the reproduction and challenge of gendered discourses in small group discussions in physics. Data for the study consisted of video recordings of eight upper secondary school groups solving physics problems and 15 audiotaped individual interviews with participating students. The analysis was based on gender theory viewing gender both as a process and a discourse. Specifically discursive psychology analysis was used to examine how students position themselves and their peers within discourses of physics and gender. The results of the study reveal how images of physics and of "skilled physics student" were constructed in the context of the interviews. These discourses were reconstructed in the students' discussions and their social interactions within groups. Traditional gendered positions were reconstructed, for example with boys positioned as more competent in physics than girls. These positions were however also resisted and challenged.

Multilevel Spondylolysis Repair Using the "Smiley Face" Technique with 3-Dimensional Intraoperative Spinal Navigation.

Science.gov (United States)

Voisin, Mathew R; Witiw, Christopher D; Deorajh, Ryan; Guha, Daipayan; Oremakinde, Adetunji; Wang, Shelly; Yang, Victor

2018-01-01

Multilevel spondylolysis is a rare cause of progressive lower back pain, and patients who fail conservative management are treated surgically. Direct repair methods can maintain mobility and lead to decreased morbidity compared with spinal fusion in single-level spondylolysis. In this paper, we present a patient with nonadjacent multilevel spondylolysis who underwent the "smiley face" technique of direct multilevel repair without fusion using 3-dimensional intraoperative spinal navigation. Bilateral spondylolysis at L3 and L5 with associated spondylolisthesis in a 50-year-old male was repaired using the "smiley face" technique. Patient-reported outcomes, including the Oswestry Disability Index (ODI) and visual analog scale scores for back and leg pain, were assessed preoperatively along with 6 weeks and 4 months postoperatively. Postoperative computed tomography imaging showed precise screw insertion and rod placement along with stable hardware alignment in follow-up imaging. The patient's ODI and lower back visual analog scale scores decreased from 25 to 8 and 7.5 to 4, respectively, correlating to an excellent outcome on ODI. Direct repair and avoidance of fusion is possible and can provide good functional outcomes in patients with nonadjacent multilevel spondylolysis and associated spondylolisthesis. Copyright © 2017 Elsevier Inc. All rights reserved.

Generalized latent variable modeling multilevel, longitudinal, and structural equation models

CERN Document Server

Skrondal, Anders; Rabe-Hesketh, Sophia

2004-01-01

This book unifies and extends latent variable models, including multilevel or generalized linear mixed models, longitudinal or panel models, item response or factor models, latent class or finite mixture models, and structural equation models.

Different groups, different motives: identity motives underlying changes in identification with novel groups.

Science.gov (United States)

Easterbrook, Matt; Vignoles, Vivian L

2012-08-01

Social identification is known to have wide-reaching implications, but theorists disagree about the underlying motives. Integrating motivated identity construction theory with recent social identity research, the authors predicted which motives underlie identification with two types of groups: interpersonal networks and social categories. In a five-wave longitudinal study of social identity processes among 268 new university residents, multilevel analyses showed that motives involved in identity enactment processes--self-esteem, belonging, and efficacy--significantly predicted within-person changes in identification with flatmates (an interpersonal network group), whereas motives involved in identity definition processes--meaning, self-esteem, and distinctiveness--significantly predicted within-person changes in identification with halls of residence (an abstract social category). This article discusses implications for research into identity motives and social identity.

Příležitosti a rizika fungování multilevel marketingu v ČR

OpenAIRE

Hašková, Lenka

2017-01-01

This paper presents the model of the business called Multilevel Marketing that is known as MLM. In the first part there is the characterization, the origin and historical development of Multilevel Marketing. The companies that became pioneers in this branch in The Czech Republic and became successful thanks to this model of the business are also mentioned in the first part of the paper. The differences between pyramid, non-ethical and illegal Multilevel Marketing are also contained in this pa...

On decoding of multi-level MPSK modulation codes

Science.gov (United States)

Lin, Shu; Gupta, Alok Kumar

1990-01-01

The decoding problem of multi-level block modulation codes is investigated. The hardware design of soft-decision Viterbi decoder for some short length 8-PSK block modulation codes is presented. An effective way to reduce the hardware complexity of the decoder by reducing the branch metric and path metric, using a non-uniform floating-point to integer mapping scheme, is proposed and discussed. The simulation results of the design are presented. The multi-stage decoding (MSD) of multi-level modulation codes is also investigated. The cases of soft-decision and hard-decision MSD are considered and their performance are evaluated for several codes of different lengths and different minimum squared Euclidean distances. It is shown that the soft-decision MSD reduces the decoding complexity drastically and it is suboptimum. The hard-decision MSD further simplifies the decoding while still maintaining a reasonable coding gain over the uncoded system, if the component codes are chosen properly. Finally, some basic 3-level 8-PSK modulation codes using BCH codes as component codes are constructed and their coding gains are found for hard decision multistage decoding.

Multi-Level Bitmap Indexes for Flash Memory Storage

Energy Technology Data Exchange (ETDEWEB)

Wu, Kesheng; Madduri, Kamesh; Canon, Shane

2010-07-23

Due to their low access latency, high read speed, and power-efficient operation, flash memory storage devices are rapidly emerging as an attractive alternative to traditional magnetic storage devices. However, tests show that the most efficient indexing methods are not able to take advantage of the flash memory storage devices. In this paper, we present a set of multi-level bitmap indexes that can effectively take advantage of flash storage devices. These indexing methods use coarsely binned indexes to answer queries approximately, and then use finely binned indexes to refine the answers. Our new methods read significantly lower volumes of data at the expense of an increased disk access count, thus taking full advantage of the improved read speed and low access latency of flash devices. To demonstrate the advantage of these new indexes, we measure their performance on a number of storage systems using a standard data warehousing benchmark called the Set Query Benchmark. We observe that multi-level strategies on flash drives are up to 3 times faster than traditional indexing strategies on magnetic disk drives.

Design and Implementation of Wiki Services in a Multilevel Secure Environment

National Research Council Canada - National Science Library

Ong, Kar L

2007-01-01

The Monterey Security Architecture (MYSEA) provides a distributed multilevel secure networking environment where authenticated users can securely access data and services at different security classification levels...

Fast multilevel radiative transfer

International Nuclear Information System (INIS)

Paletou, Frederic; Leger, Ludovick

2007-01-01

The vast majority of recent advances in the field of numerical radiative transfer relies on approximate operator methods better known in astrophysics as Accelerated Lambda-Iteration (ALI). A superior class of iterative schemes, in term of rates of convergence, such as Gauss-Seidel and successive overrelaxation methods were therefore quite naturally introduced in the field of radiative transfer by Trujillo Bueno and Fabiani Bendicho [A novel iterative scheme for the very fast and accurate solution of non-LTE radiative transfer problems. Astrophys J 1995;455:646]; it was thoroughly described for the non-LTE two-level atom case. We describe hereafter in details how such methods can be generalized when dealing with non-LTE unpolarised radiation transfer with multilevel atomic models, in monodimensional geometry

Multilevel DC link inverter

Science.gov (United States)

Su, Gui-Jia

2003-06-10

A multilevel DC link inverter and method for improving torque response and current regulation in permanent magnet motors and switched reluctance motors having a low inductance includes a plurality of voltage controlled cells connected in series for applying a resulting dc voltage comprised of one or more incremental dc voltages. The cells are provided with switches for increasing the resulting applied dc voltage as speed and back EMF increase, while limiting the voltage that is applied to the commutation switches to perform PWM or dc voltage stepping functions, so as to limit current ripple in the stator windings below an acceptable level, typically 5%. Several embodiments are disclosed including inverters using IGBT's, inverters using thyristors. All of the inverters are operable in both motoring and regenerating modes.

Charging capacitors of multilevel inverter from dc intermediate circuit

Czech Academy of Sciences Publication Activity Database

Bejvl, Martin

2011-01-01

Roč. 56, č. 2 (2011), s. 159-170 ISSN 0001-7043 R&D Projects: GA MPO FT-TA4/077 Institutional research plan: CEZ:AV0Z20570509 Keywords : electric drive * multilevel inverter * modulation and demodulation Subject RIV: JA - Electronics ; Optoelectronics, Electric al Engineering

Relating measurement invariance, cross-level invariance, and multilevel reliability

NARCIS (Netherlands)

Jak, S.; Jorgensen, T.D.

2017-01-01

Data often have a nested, multilevel structure, for example when data are collected from children in classrooms. This kind of data complicate the evaluation of reliability and measurement invariance, because several properties can be evaluated at both the individual level and the cluster level, as

Selection of DC voltage magnitude using Fibonacci series for new hybrid asymmetrical multilevel inverter with minimum PIV

Directory of Open Access Journals (Sweden)

M.R. Banaei

2014-09-01

Full Text Available Multilevel inverters are suggested to obtain high quality output voltage. In this paper, a new hybrid configuration is proposed, obtained by cascading one four switches H-bridge cell with a family of multilevel inverters. In addition, by the use of specific sequence for value of DC sources named Fibonacci series, asymmetrical topology of proposed inverter is introduced. Main advantages are that proposed inverter has least Peak Inverse Voltage (PIV than other conventional multilevel converters in both symmetric and asymmetric modes. Also, this topology doubles the number of output levels using only one cascaded four switches H-bridge cell. The PCI-1716 DAQ using PC has been used to generate switching pulses in experimental results. For presenting valid performance of proposed configuration, simulation results carried out by MATLAB/SIMULINK software and the validity of the proposed multilevel inverter is verified by experimental results.

Teachers' experiences of workplace bullying and its effects on health :|bdeveloping a multi-level intervention programme / Jaqueline de Vos

OpenAIRE

De Vos, Jaqueline

2012-01-01

Workplace bullying is recognised as a major psychosocial stressor in various professions and can have severe effects on health. Teachers are distinguished as an occupational group that is severely affected by this phenomenon. The general objectives of this research study were to firstly investigate teachers’ experiences of workplace bullying and its effects on health, and secondly, to develop a multi-level intervention programme that can be implemented to address workplace bullying and its ef...

Multilevel processor-sharing algorithm for M/G/1 systems with priorities

Energy Technology Data Exchange (ETDEWEB)

Yassouridis, A.; Koller, R.

1983-01-01

The well-known multilevel processor-sharing algorithm for M/G/1 systems without priorities is extended to M/G/1 systems with priority classes. The average response time t/sub j/(x) and the average waiting time w/sub j/(x) for a j-class job, which requires a total service of x sec, are analytically calculated. Some figures demonstrate how the priority classes and the total number of different levels affect the behaviour of the functions t/sub j/(x) and w/sub j/(x). In addition, the foreground-background algorithm with priorities, which is not yet covered in the literature, is treated as a special case of the multilevel processor-sharing algorithm. 8 references.

Effectiveness of the Triple P Positive Parenting Program on behavioral problems in children: A meta-analysis

NARCIS (Netherlands)

de Graaf, I.; Speetjens, P.; Smit, F.; de Wolff, M.; Tavecchio, L.

2008-01-01

The Triple P Positive Parenting Program is a multilevel parenting program to prevent and offer treatment for severe behavioral, emotional, and developmental problems in children. The aim of this meta-analysis is to assess the effectiveness of Triple P Level 4 interventions in the management of

Comparison of titanium and polyetheretherketone (PEEK) cages in the surgical treatment of multilevel cervical spondylotic myelopathy: a prospective, randomized, control study with over 7-year follow-up.

Science.gov (United States)

Chen, Yu; Wang, Xinwei; Lu, Xuhua; Yang, Lili; Yang, Haisong; Yuan, Wen; Chen, Deyu

2013-07-01

Anterior cervical discectomy and fusion (ACDF) with titanium- or polyetheretherketone (PEEK)-cage reconstruction is widely used in the treatment of cervical spondylotic myelopathy (CSM). This study was to compare outcomes of titanium and PEEK cages in the treatment of multilevel CSM. Between November 2002 and December 2004, a total of 80 patients with 3-level CSM were randomized in a 1:1 ratio to titanium group and PEEK group. The overall follow-up period of the patients ranged from 86 to 116 months (average 99.7 months). Clinical and radiological results were compared between titanium group and PEEK group. At the final follow-up, the clinical outcomes including JOA score, NDI score, and the excellent and good rates of clinical outcomes in the PEEK group were better than those in the titanium group. More loss of the Cobb angles and the intervertebral height was observed in the titanium group, resulting in the radiological parameters in the titanium group becoming inferior to the PEEK group at the final follow-up. Cage subsidence rates were 34.5 and 5.4% in the titanium and PEEK groups, respectively. Fusion was observed in all patients of two groups at the final follow-up. Two patients presented with cage dislocation without clinical symptoms in the titanium group. In surgical treatment of multilevel CSM, PEEK cage is superior to titanium cage in maintenance of intervertebral height and cervical lordosis, resulting in better clinical outcomes in the long-term follow-up.

Integration of multi-level marketing management systems geographically industry development

OpenAIRE

Aleksandr Lavrov; Lada Polikarpova; Alla Handramai

2015-01-01

In the article the authors attempt to develop a multi-level management system territorially industry development in market conditions, built in the widespread use of various types of marketing and their horizontal and vertical integration.

The impact of structured support groups for pregnant South African women recently diagnosed HIV positive.

Science.gov (United States)

Mundell, Jonathan P; Visser, Maretha J; Makin, Jennifer D; Kershaw, Trace S; Forsyth, Brian W C; Jeffery, Bridget; Sikkema, Kathleen J

2011-08-31

The authors of this study evaluated a structured 10-session psychosocial support group intervention for newly HIV-diagnosed pregnant South African women. Participants were expected to display increases in HIV disclosure, self-esteem, active coping and positive social support, and decreases in depression, avoidant coping, and negative social support. Three hundred sixty-one pregnant HIV-infected women were recruited from four antenatal clinics in Tshwane townships from April 2005 to September 2006. Using a quasi-experimental design, assessments were conducted at baseline and two and eight months post-intervention. A series of random effects regression analyses were conducted, with the three assessment points treated as a random effect of time. At both follow-ups, the rate of disclosure in the intervention group was significantly higher than that of the comparison group (p<0.001). Compared to the comparison group at the first follow-up, the intervention group displayed higher levels of active coping (t=2.68, p<0.05) and lower levels of avoidant coping (t=-2.02, p<0.05), and those who attended at least half of the intervention sessions exhibited improved self-esteem (t=2.11, p<0.05). Group interventions tailored for newly HIV positive pregnant women, implemented in resource-limited settings, may accelerate the process of adjusting to one's HIV status, but may not have sustainable benefits over time.

HIV, gender, race, sexual orientation, and sex work: a qualitative study of intersectional stigma experienced by HIV-positive women in Ontario, Canada.

Science.gov (United States)

Logie, Carmen H; James, Llana; Tharao, Wangari; Loutfy, Mona R

2011-11-01

HIV infection rates are increasing among marginalized women in Ontario, Canada. HIV-related stigma, a principal factor contributing to the global HIV epidemic, interacts with structural inequities such as racism, sexism, and homophobia. The study objective was to explore experiences of stigma and coping strategies among HIV-positive women in Ontario, Canada. We conducted a community-based qualitative investigation using focus groups to understand experiences of stigma and discrimination and coping methods among HIV-positive women from marginalized communities. We conducted 15 focus groups with HIV-positive women in five cities across Ontario, Canada. Data were analyzed using thematic analysis to enhance understanding of the lived experiences of diverse HIV-positive women. Focus group participants (n = 104; mean age = 38 years; 69% ethnic minority; 23% lesbian/bisexual; 22% transgender) described stigma/discrimination and coping across micro (intra/interpersonal), meso (social/community), and macro (organizational/political) realms. Participants across focus groups attributed experiences of stigma and discrimination to: HIV-related stigma, sexism and gender discrimination, racism, homophobia and transphobia, and involvement in sex work. Coping strategies included resilience (micro), social networks and support groups (meso), and challenging stigma (macro). HIV-positive women described interdependent and mutually constitutive relationships between marginalized social identities and inequities such as HIV-related stigma, sexism, racism, and homo/transphobia. These overlapping, multilevel forms of stigma and discrimination are representative of an intersectional model of stigma and discrimination. The present findings also suggest that micro, meso, and macro level factors simultaneously present barriers to health and well being--as well as opportunities for coping--in HIV-positive women's lives. Understanding the deleterious effects of stigma and discrimination

HIV, gender, race, sexual orientation, and sex work: a qualitative study of intersectional stigma experienced by HIV-positive women in Ontario, Canada.

Directory of Open Access Journals (Sweden)

Carmen H Logie

2011-11-01

Full Text Available HIV infection rates are increasing among marginalized women in Ontario, Canada. HIV-related stigma, a principal factor contributing to the global HIV epidemic, interacts with structural inequities such as racism, sexism, and homophobia. The study objective was to explore experiences of stigma and coping strategies among HIV-positive women in Ontario, Canada.We conducted a community-based qualitative investigation using focus groups to understand experiences of stigma and discrimination and coping methods among HIV-positive women from marginalized communities. We conducted 15 focus groups with HIV-positive women in five cities across Ontario, Canada. Data were analyzed using thematic analysis to enhance understanding of the lived experiences of diverse HIV-positive women. Focus group participants (n = 104; mean age = 38 years; 69% ethnic minority; 23% lesbian/bisexual; 22% transgender described stigma/discrimination and coping across micro (intra/interpersonal, meso (social/community, and macro (organizational/political realms. Participants across focus groups attributed experiences of stigma and discrimination to: HIV-related stigma, sexism and gender discrimination, racism, homophobia and transphobia, and involvement in sex work. Coping strategies included resilience (micro, social networks and support groups (meso, and challenging stigma (macro.HIV-positive women described interdependent and mutually constitutive relationships between marginalized social identities and inequities such as HIV-related stigma, sexism, racism, and homo/transphobia. These overlapping, multilevel forms of stigma and discrimination are representative of an intersectional model of stigma and discrimination. The present findings also suggest that micro, meso, and macro level factors simultaneously present barriers to health and well being--as well as opportunities for coping--in HIV-positive women's lives. Understanding the deleterious effects of stigma and

Measurement Error Correction Formula for Cluster-Level Group Differences in Cluster Randomized and Observational Studies

Science.gov (United States)

Cho, Sun-Joo; Preacher, Kristopher J.

2016-01-01

Multilevel modeling (MLM) is frequently used to detect cluster-level group differences in cluster randomized trial and observational studies. Group differences on the outcomes (posttest scores) are detected by controlling for the covariate (pretest scores) as a proxy variable for unobserved factors that predict future attributes. The pretest and…

Group as social microcosm: Within-group interpersonal style is congruent with outside group relational tendencies.

Science.gov (United States)

Goldberg, Simon B; Hoyt, William T

2015-06-01

The notion that individuals' interpersonal behaviors in the context of therapy reflects their interpersonal behaviors outside of therapy is a fundamental hypothesis underlying numerous systems of psychotherapy. The social microcosm hypothesis, in particular, claims the interpersonal therapy group becomes a reflection of group members' general tendencies, and can thus be used as information about members' interpersonal functioning as well as an opportunity for learning and behavior change. The current study tested this hypothesis using data drawn from 207 individuals participating in 22 interpersonal process groups. Ratings were made on 2 key interpersonal domains (Dominance and Affiliation) at baseline and at Weeks 2, 5, and 8 of the group. Two-level multilevel models (with participants nested within groups) were used to account for the hierarchical structure, and the social relations model (SRM; Kenny, 1994) was used to estimate peer ratings (target effects in SRM) unconfounded with rater bias. Participants showed consensus at all time points during the interpersonal process groups on one another's levels of dominance and affiliation. In addition, self- and peer ratings were stable across time and correlated with one another. Importantly, self-ratings made prior to group significantly predicted ratings (self- and peer) made within the group, with effect sizes within the medium range. Taken together, these results provide robust support for the social microcosm hypothesis and the conjecture that interpersonal style within-group therapy is reflective of broader interpersonal tendencies. (c) 2015 APA, all rights reserved).

Dual deep modeling: multi-level modeling with dual potencies and its formalization in F-Logic.

Science.gov (United States)

Neumayr, Bernd; Schuetz, Christoph G; Jeusfeld, Manfred A; Schrefl, Michael

2018-01-01

An enterprise database contains a global, integrated, and consistent representation of a company's data. Multi-level modeling facilitates the definition and maintenance of such an integrated conceptual data model in a dynamic environment of changing data requirements of diverse applications. Multi-level models transcend the traditional separation of class and object with clabjects as the central modeling primitive, which allows for a more flexible and natural representation of many real-world use cases. In deep instantiation, the number of instantiation levels of a clabject or property is indicated by a single potency. Dual deep modeling (DDM) differentiates between source potency and target potency of a property or association and supports the flexible instantiation and refinement of the property by statements connecting clabjects at different modeling levels. DDM comes with multiple generalization of clabjects, subsetting/specialization of properties, and multi-level cardinality constraints. Examples are presented using a UML-style notation for DDM together with UML class and object diagrams for the representation of two-level user views derived from the multi-level model. Syntax and semantics of DDM are formalized and implemented in F-Logic, supporting the modeler with integrity checks and rich query facilities.

Sick regimes and sick people: a multilevel investigation of the population health consequences of perceived national corruption.

Science.gov (United States)

Witvliet, Margot I; Kunst, Anton E; Arah, Onyebuchi A; Stronks, Karien

2013-10-01

There is a paucity of empirical work on the potential population health impact of living under a regime marred by corruption. African countries differ in the extent of national corruption, and we explore whether perceived national corruption is associated with population health across all rungs of society. World Health Survey data were analysed on 72 524 adults from 20 African countries. The main outcome was self-reported poor general health. Multilevel logistic regression was used to assess the association between poor health and perceived corruption, while jointly accounting for individual- and country-level human development factors. In this research, we use Transparency International's corruption perception index (CPI), which measures 'both administrative and political corruption' on a 0-10 scale. A higher score pertains to a higher rate of perceived corruption within society. We also examined effect modification by gender, age and socio-economic status. Higher national corruption perception was consistently associated with an increase in poor health prevalence, also after multivariable adjustments, with odds ratio (OR) of 1.62 (95% CI: 1.01-2.60). Stratified analyses by age and gender suggested this same pattern in all subgroups. Positive associations between poor health and perceived corruption were evident in all socio-economic groups, with the association being somewhat more positive among less educated people (OR = 1.61, 95% CI: 1.01-2.58) than among more educated people (OR = 1.40, 95% CI: 0.83-2.37). This study is a cautious first step in empirically testing the general health consequences of corruption. Our results suggest that higher perceived national corruption is associated with general health of both men and women within all socio-economic groups across the lifespan. Further research is needed using more countries to assess the magnitude of the health consequences of corruption. © 2013 John Wiley & Sons Ltd.

Multilevel Leadership and Organizational Effectiveness in Indian Technical Education: The Mediating Role of Communication, Power and Culture

Science.gov (United States)

Gochhayat, Jyotiranjan; Giri, Vijai N.; Suar, Damodar

2017-01-01

This study provides a new conceptualization of educational leadership with a multilevel and integrative approach. It examines the impact of multilevel leadership (MLL) on the effectiveness of technical educational institutes through the mediating effects of organizational communication, bases of power and organizational culture. Data were…

The effect of group attachment and social position on prosocial behavior. Evidence from lab-in-the-field experiments.

Science.gov (United States)

Baldassarri, Delia; Grossman, Guy

2013-01-01

Social life is regulated by norms of fairness that constrain selfish behavior. While a substantial body of scholarship on prosocial behavior has provided evidence of such norms, large inter- and intra-personal variation in prosocial behavior still needs to be explained. The article identifies two social-structural dimensions along which people's generosity varies systematically: group attachment and social position. We conducted lab-in-the-field experiments involving 2,597 members of producer organizations in rural Uganda. Using different variants of the dictator game, we demonstrate that group attachment positively affects prosocial behavior, and that this effect is not simply the by-product of the degree of proximity between individuals. Second, we show that occupying a formal position in an organization or community leads to greater generosity toward in-group members. Taken together, our findings show that prosocial behavior is not an invariant social trait; rather, it varies according to individuals' relative position in the social structure.

The effect of group attachment and social position on prosocial behavior. Evidence from lab-in-the-field experiments.

Directory of Open Access Journals (Sweden)

Delia Baldassarri

Full Text Available Social life is regulated by norms of fairness that constrain selfish behavior. While a substantial body of scholarship on prosocial behavior has provided evidence of such norms, large inter- and intra-personal variation in prosocial behavior still needs to be explained. The article identifies two social-structural dimensions along which people's generosity varies systematically: group attachment and social position. We conducted lab-in-the-field experiments involving 2,597 members of producer organizations in rural Uganda. Using different variants of the dictator game, we demonstrate that group attachment positively affects prosocial behavior, and that this effect is not simply the by-product of the degree of proximity between individuals. Second, we show that occupying a formal position in an organization or community leads to greater generosity toward in-group members. Taken together, our findings show that prosocial behavior is not an invariant social trait; rather, it varies according to individuals' relative position in the social structure.

Rethinking capacity building for knowledge mobilisation: developing multilevel capabilities in healthcare organisations.

Science.gov (United States)

Kislov, Roman; Waterman, Heather; Harvey, Gill; Boaden, Ruth

2014-11-15

subsequent trajectory of newly developed knowledge and skills within the recipient healthcare organisations. The analysis leads to four principles underpinning a practice-based approach to developing multilevel knowledge mobilisation capabilities: (1) moving from 'building' capacity from scratch towards 'developing' capacity of healthcare organisations; (2) moving from passive involvement in formal education and training towards active, continuous participation in knowledge mobilisation practices; (3) moving from lower-order, project-specific capabilities towards higher-order, generic capabilities allowing healthcare organisations to adapt to change, absorb new knowledge and innovate; and (4) moving from single-level to multilevel capability development involving transitions between individual, group and organisational learning.

Income Inequality and Risk of Suicide in New York City Neighborhoods: A Multilevel Case-Control Study

Science.gov (United States)

Miller, Jeffrey R.; Piper, Tinka Markham; Ahern, Jennifer; Tracy, Melissa; Tardiff, Kenneth J.; Vlahov, David; Galea, Sandro

2005-01-01

Evidence on the relationship between income inequality and suicide is inconsistent. Data from the New York City Office of the Chief Medical Examiner for all fatal injuries was collected to conduct a multilevel case-control study. In multilevel models, suicide decedents (n = 374) were more likely than accident controls (n = 453) to reside in…

Individualist-Collectivist Culture and Trust Radius : A Multilevel Approach

NARCIS (Netherlands)

van Hoorn, André

We apply a multilevel approach to examine empirically the nexus between individualist and collectivist culture on the one hand and people’s radius of trust on the other. People’s trust level (i.e., the intensity with which people trust other people) has been extensively studied. Increasingly,

Daily Stressors in School-Age Children: A Multilevel Approach

Science.gov (United States)

Escobar, Milagros; Alarcón, Rafael; Blanca, María J.; Fernández-Baena, F. Javier; Rosel, Jesús F.; Trianes, María Victoria

2013-01-01

This study uses hierarchical or multilevel modeling to identify variables that contribute to daily stressors in a population of schoolchildren. Four hierarchical levels with several predictive variables were considered: student (age, sex, social adaptation of the student, number of life events and chronic stressors experienced, and educational…

Trastuzumab beyond progression in human epidermal growth factor receptor 2-positive advanced breast cancer: a german breast group 26/breast international group 03-05 study

DEFF Research Database (Denmark)

von Minckwitz, Gunter; du Bois, Andreas; Schmidt, Marcus

2009-01-01

PURPOSE: Trastuzumab shows clinical activity in human epidermal growth factor receptor 2 (HER-2)-positive early and advanced breast cancer. In the German Breast Group 26/Breast International Group 03-05 trial, we investigated if trastuzumab treatment should be continued beyond progression. METHODS......: Patients with HER-2-positive breast cancer that progresses during treatment with trastuzumab were randomly assigned to receive capecitabine (2,500 mg/m(2) body-surface area on days 1 through 14 [1,250 mg/m(2) semi-daily]) alone or with continuation of trastuzumab (6 mg/kg body weight) in 3-week cycles....... The primary end point was time to progression. RESULTS: We randomly assigned 78 patients to capecitabine and 78 patients to capecitabine plus trastuzumab. Sixty-five events and 38 deaths in the capecitabine group and 62 events and 33 deaths in the capecitabine-plus-trastuzumab group occurred during 15...

Adaptive Multilevel Monte Carlo Simulation

KAUST Repository

Hoel, H

2011-08-23

This work generalizes a multilevel forward Euler Monte Carlo method introduced in Michael B. Giles. (Michael Giles. Oper. Res. 56(3):607–617, 2008.) for the approximation of expected values depending on the solution to an Itô stochastic differential equation. The work (Michael Giles. Oper. Res. 56(3):607– 617, 2008.) proposed and analyzed a forward Euler multilevelMonte Carlo method based on a hierarchy of uniform time discretizations and control variates to reduce the computational effort required by a standard, single level, Forward Euler Monte Carlo method. This work introduces an adaptive hierarchy of non uniform time discretizations, generated by an adaptive algorithmintroduced in (AnnaDzougoutov et al. Raùl Tempone. Adaptive Monte Carlo algorithms for stopped diffusion. In Multiscale methods in science and engineering, volume 44 of Lect. Notes Comput. Sci. Eng., pages 59–88. Springer, Berlin, 2005; Kyoung-Sook Moon et al. Stoch. Anal. Appl. 23(3):511–558, 2005; Kyoung-Sook Moon et al. An adaptive algorithm for ordinary, stochastic and partial differential equations. In Recent advances in adaptive computation, volume 383 of Contemp. Math., pages 325–343. Amer. Math. Soc., Providence, RI, 2005.). This form of the adaptive algorithm generates stochastic, path dependent, time steps and is based on a posteriori error expansions first developed in (Anders Szepessy et al. Comm. Pure Appl. Math. 54(10):1169– 1214, 2001). Our numerical results for a stopped diffusion problem, exhibit savings in the computational cost to achieve an accuracy of ϑ(TOL),from(TOL−3), from using a single level version of the adaptive algorithm to ϑ(((TOL−1)log(TOL))2).

A Grouping Particle Swarm Optimizer with Personal-Best-Position Guidance for Large Scale Optimization.

Science.gov (United States)

Guo, Weian; Si, Chengyong; Xue, Yu; Mao, Yanfen; Wang, Lei; Wu, Qidi

2017-05-04

Particle Swarm Optimization (PSO) is a popular algorithm which is widely investigated and well implemented in many areas. However, the canonical PSO does not perform well in population diversity maintenance so that usually leads to a premature convergence or local optima. To address this issue, we propose a variant of PSO named Grouping PSO with Personal- Best-Position (Pbest) Guidance (GPSO-PG) which maintains the population diversity by preserving the diversity of exemplars. On one hand, we adopt uniform random allocation strategy to assign particles into different groups and in each group the losers will learn from the winner. On the other hand, we employ personal historical best position of each particle in social learning rather than the current global best particle. In this way, the exemplars diversity increases and the effect from the global best particle is eliminated. We test the proposed algorithm to the benchmarks in CEC 2008 and CEC 2010, which concern the large scale optimization problems (LSOPs). By comparing several current peer algorithms, GPSO-PG exhibits a competitive performance to maintain population diversity and obtains a satisfactory performance to the problems.

Model Promosi Kesehatan di Tempat Kerja Multilevel: Bagaimana Implementasinya dalam Mengubah Perilaku Pekerja? (Suatu Kajian Kepustakaan

Directory of Open Access Journals (Sweden)

Zahtamal .

2015-05-01

Full Text Available Konsekuensi dari penyakit-penyakit yang sering dialami oleh pekerja merupakan kerugian besar bagi perusahaan dan pekerja. Dalam rangka mengatasi persoalan penyakit pada pekerja, perlu upaya promosi kesehatan di tempat kerja, khususnya untuk mengubah perilaku. Penerapan perubahan perilaku di tempat kerja bersifat lebih kompleks. Perubahan perilaku tidak saja didorong oleh faktor-faktor individu, tetapi juga oleh peran faktor eksternal, sehingga pihak yang dijadikan sasaran workplace health promotion (WHP adalah secara multilevel. Artikel ini menjelaskan rumusan model WHP multilevel yang dapat diterapkan untuk mengubah perilaku pekerja yang tidak sehat, sehingga diharapkan dapat menurunkan kesakitan dan kematian penyakit pada pekerja. Prinsip pemilihan model perubahan perilaku, perlu  diperhatikan dalam merumuskan WHP secara multilevel. Hal ini dijadikan sebagai acuan memodifikasi perilaku yang akan dituju. Selanjutnya, prinsip memilih strategi dan metode perubahan perilaku, disesuaikan dengan level sasaran yang diintervensi. Secara keseluruhan, prinsip-prinsip ini dirumuskan dalam sebuah acuan program WHP secara komprehensif dan dilaksanakan dengan efektif dan efisien di tempat kerja. Artikel ini dapat menjadi acuan bagi pihak yang akan mengimplementasikan WHP dengan pendekatan perubahan perilaku secara multilevel. 

A multivariate multilevel Gaussian model with a mixed effects structure in the mean and covariance part.

Science.gov (United States)

Li, Baoyue; Bruyneel, Luk; Lesaffre, Emmanuel

2014-05-20

A traditional Gaussian hierarchical model assumes a nested multilevel structure for the mean and a constant variance at each level. We propose a Bayesian multivariate multilevel factor model that assumes a multilevel structure for both the mean and the covariance matrix. That is, in addition to a multilevel structure for the mean we also assume that the covariance matrix depends on covariates and random effects. This allows to explore whether the covariance structure depends on the values of the higher levels and as such models heterogeneity in the variances and correlation structure of the multivariate outcome across the higher level values. The approach is applied to the three-dimensional vector of burnout measurements collected on nurses in a large European study to answer the research question whether the covariance matrix of the outcomes depends on recorded system-level features in the organization of nursing care, but also on not-recorded factors that vary with countries, hospitals, and nursing units. Simulations illustrate the performance of our modeling approach. Copyright © 2013 John Wiley & Sons, Ltd.

Multi-Level Determinants of Parasitic Fly Infection in Forest Passerines

Science.gov (United States)

Manzoli, Darío Ezequiel; Antoniazzi, Leandro Raúl; Saravia, María José; Silvestri, Leonardo; Rorhmann, David; Beldomenico, Pablo Martín

2013-01-01

The study of myiasis is important because they may cause problems to the livestock industry, public health, or wildlife conservation. The ecology of parasitic dipterans that cause myiasis is singular, as they actively seek their hosts over relatively long distances. However, studies that address the determinants of myiasis dynamics are very scarce. The genus Philornis include species that may be excellent models to study myiasis ecology, as they exclusively parasitize bird nestlings, which stay in their nests until they are fully fledged, and larvae remain at the point of entry until the parasitic stage is over, thus allowing the collection of sequential individual-level infection data from virtually all the hosts present at a particular area. Here we offer a stratified multi-level analysis of longitudinal data of Philornis torquans parasitism in replicated forest bird communities of central Argentina. Using Generalized Linear Models and Generalized Linear Mixed Models and an information theory approach for model selection, we conducted four groups of analyses, each with a different study unit, the individual, the brood, the community at a given week, and the community at a given year. The response variable was larval abundance per nestling or mean abundance per nestling. At each level, models included the variables of interest of that particular level, and also potential confounders and effect modifiers of higher levels. We found associations of large magnitude at all levels, but only few variables truly governed the dynamics of this parasite. At the individual level, the infection was determined by the species and the age of the host. The main driver of parasite abundance at the microhabitat level was the average height of the forest, and at the community level, the density of hosts and prior rainfall. This multi-level approach contributed to a better understanding of the ecology of myiasis. PMID:23874408

Extended SVM algorithms for multilevel trans-Z-source inverter

Directory of Open Access Journals (Sweden)

Aida Baghbany Oskouei

2016-03-01

Full Text Available This paper suggests extended algorithms for multilevel trans-Z-source inverter. These algorithms are based on space vector modulation (SVM, which works with high switching frequency and does not generate the mean value of the desired load voltage in every switching interval. In this topology the output voltage is not limited to dc voltage source similar to traditional cascaded multilevel inverter and can be increased with trans-Z-network shoot-through state control. Besides, it is more reliable against short circuit, and due to several number of dc sources in each phase of this topology, it is possible to use it in hybrid renewable energy. Proposed SVM algorithms include the following: Combined modulation algorithm (SVPWM and shoot-through implementation in dwell times of voltage vectors algorithm. These algorithms are compared from viewpoint of simplicity, accuracy, number of switching, and THD. Simulation and experimental results are presented to demonstrate the expected representations.

Enhanced DC-Link Capacitor Voltage Balancing Control of DC–AC Multilevel Multileg Converters

DEFF Research Database (Denmark)

Busquets-Monge, Sergio; Maheshwari, Ram Krishan; Nicolas-Apruzzese, Joan

2015-01-01

This paper presents a capacitor voltage balancing control applicable to any multilevel dc–ac converter formed by a single set of series-connected capacitors implementing the dc link and semiconductor devices, such as the diode-clamped topology. The control is defined for any number of dc-link vol......This paper presents a capacitor voltage balancing control applicable to any multilevel dc–ac converter formed by a single set of series-connected capacitors implementing the dc link and semiconductor devices, such as the diode-clamped topology. The control is defined for any number of dc...

Performance Comparison of Assorted Color Spaces for Multilevel Block Truncation Coding based Face Recognition

OpenAIRE

H.B. Kekre; Sudeep Thepade; Karan Dhamejani; Sanchit Khandelwal; Adnan Azmi

2012-01-01

The paper presents a performance analysis of Multilevel Block Truncation Coding based Face Recognition among widely used color spaces. In [1], Multilevel Block Truncation Coding was applied on the RGB color space up to four levels for face recognition. Better results were obtained when the proposed technique was implemented using Kekre’s LUV (K’LUV) color space [25]. This was the motivation to test the proposed technique using assorted color spaces. For experimental analysis, two face databas...

A New Family of Multilevel Grid Connected Inverters Based on Packed U Cell Topology.

Science.gov (United States)

Pakdel, Majid; Jalilzadeh, Saeid

2017-09-29

In this paper a novel packed U cell (PUC) based multilevel grid connected inverter is proposed. Unlike the U cell arrangement which consists of two power switches and one capacitor, in the proposed converter topology a lower DC power supply from renewable energy resources such as photovoltaic arrays (PV) is used as a base power source. The proposed topology offers higher efficiency and lower cost using a small number of power switches and a lower DC power source which is supplied from renewable energy resources. Other capacitor voltages are extracted from the base lower DC power source using isolated DC-DC power converters. The operation principle of proposed transformerless multilevel grid connected inverter is analyzed theoretically. Operation of the proposed multilevel grid connected inverter is verified through simulation studies. An experimental prototype using STM32F407 discovery controller board is performed to verify the simulation results.

Social and individual risk factors for suicide ideation among Chinese children and adolescents: A multilevel analysis.

Science.gov (United States)

Tan, Ling; Xia, Tiansheng; Reece, Christy

2018-04-01

The objective of this study was to investigate the prevalence and predictors of suicide ideation among primary, middle and high school students. We used multilevel modelling to investigate suicide ideation among 12,733 Chinese children and adolescents aged 9-18 years from wide range of areas across China. Approximately, 32.09% of children and adolescents reported suicide ideation, with females were more likely to report suicide ideation than males (38.09% vs. 29.95%). Our results showed that the risk factors in primary school students were different from middle and high school student groups, whereas significant risk factors for middle and high school students were similar. The city's standard of living as indicated by the Engel coefficient and the city's divorce rate were positively associated with the prevalence of suicide ideation; in contrast, the school's pupil-to-teacher ratio was negatively correlated with elevated suicide ideation. Significant risk factors for suicide ideation included study anxiety, self-accusation tendency, impulsive tendency, terror tendency and physical symptoms. These results have important implications for the prevention of suicide, suggesting that both contextual (city-level) and compositional (individual-level) factors could be important targets for prevention and intervention for children and adolescents at risk of suicide ideation. © 2016 International Union of Psychological Science.

Multi-level spondylolysis.

Science.gov (United States)

Hersh, David S; Kim, Yong H; Razi, Afshin

2011-01-01

The incidence of isthmic spondylolysis is approximately 3% to 6% in the general population. Spondylolytic defects involving multiple vertebral levels, on the other hand, are extremely rare. Only a handful of reports have examined the outcomes of surgical treatment of multi-level spondylolysis. Here, we present one case of bilateral pars defects at L3, L4, and L5. The patient, a 46-year-old female, presented with lower back pain radiating into the left lower extremity. Radiographs and CT scans of the lumbar spine revealed bilateral pars defects at L3-L5. The patient underwent lumbar discectomy and interbody fusion of L4-S1 as well as direct repair of the pars defect at L3. There were no postoperative complications, and by seven months the patient had improved clinically. While previous reports describe the use of either direct repair or fusion in the treatment of spondylolysis, we are unaware of reports describing the use of both techniques at adjacent levels.

The EU as Multilevel Democracy: Conceptual and Practical Challenges

NARCIS (Netherlands)

Crum, B.J.J.

2016-01-01

The aim of this paper is to systematically think through the implications of conceiving of the European Union as a ‘multilevel democracy’. The central claim on which this notion depends is that parliamentary sovereignty in the EU is not embodied in a single institution but remains essentially

Multilevel Balancing Domain Decomposition by Constraints Deluxe Algorithms with Adaptive Coarse Spaces for Flow in Porous Media

KAUST Repository

Zampini, Stefano; Tu, Xuemin

2017-01-01

Multilevel balancing domain decomposition by constraints (BDDC) deluxe algorithms are developed for the saddle point problems arising from mixed formulations of Darcy flow in porous media. In addition to the standard no-net-flux constraints on each face, adaptive primal constraints obtained from the solutions of local generalized eigenvalue problems are included to control the condition number. Special deluxe scaling and local generalized eigenvalue problems are designed in order to make sure that these additional primal variables lie in a benign subspace in which the preconditioned operator is positive definite. The current multilevel theory for BDDC methods for porous media flow is complemented with an efficient algorithm for the computation of the so-called malign part of the solution, which is needed to make sure the rest of the solution can be obtained using the conjugate gradient iterates lying in the benign subspace. We also propose a new technique, based on the Sherman--Morrison formula, that lets us preserve the complexity of the subdomain local solvers. Condition number estimates are provided under certain standard assumptions. Extensive numerical experiments confirm the theoretical estimates; additional numerical results prove the effectiveness of the method with higher order elements and high-contrast problems from real-world applications.

Multilevel Balancing Domain Decomposition by Constraints Deluxe Algorithms with Adaptive Coarse Spaces for Flow in Porous Media

KAUST Repository

Zampini, Stefano

2017-08-03

Multilevel balancing domain decomposition by constraints (BDDC) deluxe algorithms are developed for the saddle point problems arising from mixed formulations of Darcy flow in porous media. In addition to the standard no-net-flux constraints on each face, adaptive primal constraints obtained from the solutions of local generalized eigenvalue problems are included to control the condition number. Special deluxe scaling and local generalized eigenvalue problems are designed in order to make sure that these additional primal variables lie in a benign subspace in which the preconditioned operator is positive definite. The current multilevel theory for BDDC methods for porous media flow is complemented with an efficient algorithm for the computation of the so-called malign part of the solution, which is needed to make sure the rest of the solution can be obtained using the conjugate gradient iterates lying in the benign subspace. We also propose a new technique, based on the Sherman--Morrison formula, that lets us preserve the complexity of the subdomain local solvers. Condition number estimates are provided under certain standard assumptions. Extensive numerical experiments confirm the theoretical estimates; additional numerical results prove the effectiveness of the method with higher order elements and high-contrast problems from real-world applications.

The Relationship Among School Safety, School Liking, and Students' Self-Esteem: Based on a Multilevel Mediation Model.

Science.gov (United States)

Zhang, Xinghui; Xuan, Xin; Chen, Fumei; Zhang, Cai; Luo, Yuhan; Wang, Yun

2016-03-01

Perceptions of school safety have an important effect on students' development. Based on the model of "context-process-outcomes," we examined school safety as a context variable to explore how school safety at the school level affected students' self-esteem. We used hierarchical linear modeling to examine the link between school safety at the school level and students' self-esteem, including school liking as a mediator. The data were from the National Children's Study of China (NCSC), in which 6618 fourth- to fifth-grade students in 79 schools were recruited from 100 counties in 31 provinces in China. Multilevel mediation analyses showed that the positive relationship between school safety at the school level and self-esteem was partially mediated by school liking, controlling for demographics at both student and school levels. Furthermore, a sex difference existed in the multilevel mediation model. For boys, school liking fully mediated the relationship between school safety at the school level and self-esteem. However, school liking partially mediated the relationship between school safety at the school level and self-esteem among girls. School safety should receive increasing attention from policymakers because of its impact on students' self-esteem. © 2016, American School Health Association.

Multilevel flow modelling of process plant for diagnosis and control

International Nuclear Information System (INIS)

Lind, M.

1982-08-01

The paper describes the multilevel flow modelling methodology which can be used to construct functional models of energy and material processing systems. The models describe mass and energy flow topology on different levels of abstraction and represent the hierarchical functional structure of complex systems. A model of a nuclear power plant (PWR) is presented in the paper for illustration. Due to the consistency of the method, multilevel flow models provide specifications of plant goals and functions and may be used as a basis for design of computer-based support systems for the plant operator. Plant control requirements can be derived from the models and due to independence of the actual controller implementation the method may be used as basic for design of control strategies and for the allocation of control tasks to the computer and the plant operator. (author)

Multilevel Flow Modelling of Process Plant for Diagnosis and Control

DEFF Research Database (Denmark)

Lind, Morten

1982-01-01

The paper describes the multilevel flow modelling methodology which can be used to construct functional models of energy and material processing systems. The models describe mass and energy flow topology on different levels of abstraction and represent the hierarchical functional structure...... of complex systems. A model of a nuclear power plant (PWR) is presented in the paper for illustration. Due to the consistency of the method, multilevel flow models provide specifications of plant goals and functions and may be used as a basis for design of computer-based support systems for the plant...... operator. Plant control requirements can be derived from the models and due to independence of the actual controller implementation the method may be used as a basis for design of control strategies and for the allocation of control tasks to the computer and the plant operator....

The median hazard ratio: a useful measure of variance and general contextual effects in multilevel survival analysis.

Science.gov (United States)

Austin, Peter C; Wagner, Philippe; Merlo, Juan

2017-03-15

Multilevel data occurs frequently in many research areas like health services research and epidemiology. A suitable way to analyze such data is through the use of multilevel regression models (MLRM). MLRM incorporate cluster-specific random effects which allow one to partition the total individual variance into between-cluster variation and between-individual variation. Statistically, MLRM account for the dependency of the data within clusters and provide correct estimates of uncertainty around regression coefficients. Substantively, the magnitude of the effect of clustering provides a measure of the General Contextual Effect (GCE). When outcomes are binary, the GCE can also be quantified by measures of heterogeneity like the Median Odds Ratio (MOR) calculated from a multilevel logistic regression model. Time-to-event outcomes within a multilevel structure occur commonly in epidemiological and medical research. However, the Median Hazard Ratio (MHR) that corresponds to the MOR in multilevel (i.e., 'frailty') Cox proportional hazards regression is rarely used. Analogously to the MOR, the MHR is the median relative change in the hazard of the occurrence of the outcome when comparing identical subjects from two randomly selected different clusters that are ordered by risk. We illustrate the application and interpretation of the MHR in a case study analyzing the hazard of mortality in patients hospitalized for acute myocardial infarction at hospitals in Ontario, Canada. We provide R code for computing the MHR. The MHR is a useful and intuitive measure for expressing cluster heterogeneity in the outcome and, thereby, estimating general contextual effects in multilevel survival analysis. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

Habit, custom, and power: a multi-level theory of population health.

Science.gov (United States)

Zimmerman, Frederick J

2013-03-01

In multi-level theory, individual behavior flows from cognitive habits, either directly through social referencing, rules of thumb, or automatic behaviors; or indirectly through the shaping of rationality itself by framing or heuristics. Although behavior does not arise from individually rational optimization, it generally appears to be rational, because the cognitive habits that guide behavior evolve toward optimality. However, power imbalances shaped by particular social, political, and economic structures can distort this evolution, leading to individual behavior that fails to maximize individual or social well-being. Replacing the dominant rational-choice paradigm with a multi-level theoretical paradigm involving habit, custom, and power will enable public health to engage in rigorous new areas of research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Multilevel resonance parameters of 241Pu

International Nuclear Information System (INIS)

Weston, L.W.; Todd, J.H.

1978-01-01

The data previously reported by the authors on the neutron fission and capture cross sections of 241 Pu were simultaneously fit with the Adler formalism to obtain multilevel resonance parameters. The neutron energy range of the fit was 0.01 to 100 eV. The 241 Pu cross sections in the resonance region of neutron energies are complex, and the Adler parameters present an efficient method of representing these cross sections, which are important for plutonium-fueled reactors. The parameters represent the data to an accuracy within the quoted experimental errors. 5 figures, 2 tables

Multilevel parametrization of fissile nuclei resonance cross sections

International Nuclear Information System (INIS)

Lukyanov, A.A.; Kolesov, V.V.; Janeva, N.

1987-01-01

Because the resonance interference has an important influence on the resonance structure of neutron cross sections energy dependence at lowest energies, multilevel scheme of the cross section parametrization which take into account the resonance interference is used for the description with the same provisions in the regions of the interferential maximum and minimum of the resonance cross sections of the fissile nuclei

A fast photo-counter with multi-level buffers

International Nuclear Information System (INIS)

Peng Hu; Zhou Peiling; Yao Kun; Guo Guangcan

1992-01-01

Digital Photon Correlator (DPC) is composed of a Photo-counter and a data processing unit. The performance of Photo-counter in data acquisition system has a direct influence on data processing. The Photo-counter with fast carry designed here has multi-level buffers. Photon pulses can be correctly and dynamically recorded by the Photo-counter and processed by a single chip computer

An Adaptive Multilevel Factorized Sparse Approximate Inverse Preconditioning

Czech Academy of Sciences Publication Activity Database

Kopal, Jiří; Rozložník, Miroslav; Tůma, Miroslav

2017-01-01

Roč. 113, November (2017), s. 19-24 ISSN 0965-9978 R&D Projects: GA ČR GA13-06684S Grant - others:GA MŠk(CZ) LL1202 Institutional support: RVO:67985807 Keywords : approximate inverse * Gram–Schmidt orthogonalization * incomplete factorization * multilevel methods * preconditioned conjugate gradient method Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 3.000, year: 2016

Totally parallel multilevel algorithms

Science.gov (United States)

Frederickson, Paul O.

1988-01-01

Four totally parallel algorithms for the solution of a sparse linear system have common characteristics which become quite apparent when they are implemented on a highly parallel hypercube such as the CM2. These four algorithms are Parallel Superconvergent Multigrid (PSMG) of Frederickson and McBryan, Robust Multigrid (RMG) of Hackbusch, the FFT based Spectral Algorithm, and Parallel Cyclic Reduction. In fact, all four can be formulated as particular cases of the same totally parallel multilevel algorithm, which are referred to as TPMA. In certain cases the spectral radius of TPMA is zero, and it is recognized to be a direct algorithm. In many other cases the spectral radius, although not zero, is small enough that a single iteration per timestep keeps the local error within the required tolerance.

THE CREATION OF ANALYTICAL PREDICATION CONCEPT IN MULTILEVEL ORGANIZATION SYSTEM MANAGEMENT

Directory of Open Access Journals (Sweden)

O. M. Pisareva

2013-01-01

Full Text Available This article deals with analytical and forecasting methodology problems in the integrated business systems management. The theoretical framework of analytical predication concept in multilevel organization systems is presented.

Elimination of harmonics in multilevel inverters with non-equal dc sources using PSO

International Nuclear Information System (INIS)

Al-Othman, A.K.; Abdelhamid, Tamer H.

2009-01-01

Multilevel inverters supplied from equal and constant dc sources almost do not exist in practical applications. The variation of the dc sources affects the values of the switching angles required for each specific harmonic profile, as well as increases the difficulty of the harmonic elimination's equations. This paper presents an extremely fast optimal solution of harmonic elimination of multilevel inverters with non-equal dc sources using a novel Particle Swarm Optimization (PSO) algorithm. The overall system is suitable for large variable speed drives, UPS systems, and on-line utility applications such as static var compensation. A set of mathematical equations describing the general output waveform of the multilevel inverter with non-equal dc sources is formulated. PSO is then employed to compute the optimal solution set of switching angles, if it exists, for each required harmonic profile. Theoretical studies for different case studies regarding the number of levels and harmonic profile are carried out to show the effectiveness and robustness of the proposed technique, and validated through both simulations and laboratory experimentation

A multilevel model of patient safety culture: cross-level relationship between organizational culture and patient safety behavior in Taiwan's hospitals.

Science.gov (United States)

Chen, I-Chi; Ng, Hui-Fuang; Li, Hung-Hui

2012-01-01

As health-care organizations endeavor to improve their quality of care, there is a growing recognition of the importance of establishing a culture of patient safety. The main objective of this study was to investigate the cross-level influences of organizational culture on patient safety behavior in Taiwan's hospitals. The authors measured organizational culture (bureaucratic, supportive and innovative culture), patient safety culture and behavior from 788 hospital workers among 42 hospitals in Taiwan. Multilevel analysis was applied to explore the relationship between organizational culture (group level) and patient safety behavior (individual level). Patient safety culture had positive impact on patient safety behavior in Taiwan's hospitals. The results also indicated that bureaucratic, innovative and supportive organizational cultures all had direct influence on patient safety behavior. However, only supportive culture demonstrated significant moderation effect on the relationship between patient safety culture and patient safety behavior. Furthermore, organizational culture strength was shown correlated negatively with patient safety culture variability. Overall, organizational culture plays an important role in patient safety activities. Safety behaviors of hospital staff are partly influenced by the prevailing cultural norms in their organizations and work groups. For management implications, constructed patient priority from management commitment to leadership is necessary. For academic implications, research on patient safety should consider leadership, group dynamics and organizational learning. These factors are important for understanding the barriers and the possibilities embedded in patient safety. Copyright © 2011 John Wiley & Sons, Ltd.

Help Seeking in Online Collaborative Groupwork: A Multilevel Analysis

Science.gov (United States)

Du, Jianxia; Xu, Jianzhong; Fan, Xitao

2015-01-01

This study examined predictive models for students' help seeking in the context of online collaborative groupwork. Results from multilevel analysis revealed that most of the variance in help seeking was at the individual student level, and multiple variables at the individual level were predictive of help-seeking behaviour. Help seeking was…

Design of shared unit-dose drug distribution network using multi-level particle swarm optimization.

Science.gov (United States)

Chen, Linjie; Monteiro, Thibaud; Wang, Tao; Marcon, Eric

2018-03-01

Unit-dose drug distribution systems provide optimal choices in terms of medication security and efficiency for organizing the drug-use process in large hospitals. As small hospitals have to share such automatic systems for economic reasons, the structure of their logistic organization becomes a very sensitive issue. In the research reported here, we develop a generalized multi-level optimization method - multi-level particle swarm optimization (MLPSO) - to design a shared unit-dose drug distribution network. Structurally, the problem studied can be considered as a type of capacitated location-routing problem (CLRP) with new constraints related to specific production planning. This kind of problem implies that a multi-level optimization should be performed in order to minimize logistic operating costs. Our results show that with the proposed algorithm, a more suitable modeling framework, as well as computational time savings and better optimization performance are obtained than that reported in the literature on this subject.

Active control of flying capacitor currents in multilevel voltage-source inverters

Czech Academy of Sciences Publication Activity Database

Kokeš, Petr; Semerád, Radko

2013-01-01

Roč. 58, č. 4 (2013), s. 393-410 ISSN 0001-7043 Institutional support: RVO:61388998 Keywords : voltage source inverter (VSI) * multilevel inverter * flying capacitor Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

Multilevel lumbar fusion and postoperative physiotherapy rehabilitation in a patient with persistent pain.

Science.gov (United States)

Pons, Tracey; Shipton, Edward A

2011-04-01

There are no comparative randomised controlled trials of physiotherapy modalities for chronic low back and radicular pain associated with multilevel fusion. Physiotherapy-based rehabilitation to control pain and improve activation levels for persistent pain following multilevel fusion can be challenging. This is a case report of a 68-year-old man who was referred for physiotherapy intervention 10 months after a multilevel spinal fusion for spinal stenosis. He reported high levels of persistent postoperative pain with minimal activity as a consequence of his pain following the surgery. The physiotherapy interventions consisted of three phases of rehabilitation starting with pool exercise that progressed to land-based walking. These were all combined with transcutaneous electrical nerve stimulation (TENS) that was used consistently for up to 8 hours per day. As outcome measures, daily pain levels and walking distances were charted once the pool programme was completed (in the third phase). Phase progression was determined by shuttle test results. The pain level was correlated with the distance walked using linear regression over a 5-day average. Over a 5-day moving average, the pain level reduced and walking distance increased. The chart of recorded pain level and walking distance showed a trend toward decreased pain with the increased distance walked. In a patient undergoing multilevel lumbar fusion, the combined use of TENS and a progressive walking programme (from pool to land) reduced pain and increased walking distance. This improvement was despite poor medication compliance and a reported high level of postsurgical pain.

Just how multi-level is leadership research? A document co-citation analysis 1980–2013 on leadership constructs and outcomes

OpenAIRE

Batistic, S.; Cerne, M.; Vogel, Bernd

2017-01-01

The use of multi-level theories and methodologies in leadership has gained momentum in recent years. However, the leadership field still suffers from a fragmented and unclear evolution and practice of multi-level approaches. The questions of how and to what extent multi-level research has evolved in both leadership phenomena and leadership outcomes, and which informal research networks drove this evolution, remain vastly unexplored. In this study, the extent of literature published between 19...

Reciprocity and depressive symptoms in Belgian workers: a cross-sectional multilevel analysis.

Science.gov (United States)

De Clercq, Bart; Clays, Els; Janssens, Heidi; De Bacquer, Dirk; Casini, Annalisa; Kittel, France; Braeckman, Lutgart

2013-07-01

This study examines the multidimensional association between reciprocity at work and depressive symptoms. Data from the Belgian BELSTRESS survey (32 companies; N = 24,402) were analyzed. Multilevel statistical procedures were used to account for company-level associations while controlling for individual-level associations. Different dimensions of individual reciprocity were negatively associated with depressive symptoms. On the company level, only vertical emotional reciprocity was negatively associated (β = -4.660; SE = 1.117) independently from individual reciprocity (β = -0.557; SE = 0.042). Complex interactions were found such that workplace reciprocity (1) may not uniformly benefit individuals and (2) related differently to depressive symptoms, depending on occupational group. This study extends the existing literature with evidence on the multidimensional, contextual, and cross-level interaction associations of reciprocity as a key aspect of social capital on depressive symptoms.

Multilevel interfaces for power plant control rooms I: An integrative review

International Nuclear Information System (INIS)

Vicente, K.J.

1992-01-01

Events that are unfamiliar to operators and that have not been anticipated by designers pose the greatest threat to system safety in nuclear power plants. The abstraction hierarchy has been proposed as a representation framework that can be adopted to design interfaces that support operators in dealing with these unanticipated events. This multilevel representation format represents a plant in terms of both physical and functional constraints. This article reviews, for the first time, the work that has been done in academia, industry, and research laboratories on multilevel interfaces based on the abstraction hierarchy. The review indicates that there are many degrees of freedom in designing an interface based on the abstraction hierarchy but that very little systematic work has been done in evaluating how best to deal with those degrees of freedom. As a result, there is very little defensible guidance to provide designers. As a first step in overcoming this barrier, a companion paper uses the results of the review presented here to develop a preliminary design space for multilevel interfaces based on the abstraction hierarchy. This space serves several worthwhile purposes relevant not only to research but also to design and regulation as well. Consequently this complementary set of papers should be of interest to researchers, designers, and regulators concerned with nuclear power-plant control rooms. 53 refs., 8 figs

Does the Occasion Justify the Denunciation?: a Multilevel Approach for Brazilian Accountants

Directory of Open Access Journals (Sweden)

Bernardo de Abreu Guelber Fajardo

2014-01-01

Full Text Available Frauds represent large losses to the global economy, and one of the main means for their containment is by means of denunciations within organizations: whistle blowing. This research aims to analyze whistle blowing within the Brazilian context, considering the influence of costs and intrinsic benefits as well as aspects of the individual's interaction with his/her organization, profession and society at large. By means of a questionnaire answered by 124 accountants, a multilevel model was applied to analyze these aspects. The results demonstrate the importance of situational aspects as a positive influence in favor of denunciations. These results are useful for organizations and regulatory institutions in developing institutional mechanisms to encourage denunciation. Moreover, the results are also useful for teachers of professional ethics and members of the Federal and Regional Accounting Councils, which are dedicated to the assessment of alleged deviations from the professional code of ethics.

Multilevel converters for 10 MW Wind Turbines

DEFF Research Database (Denmark)

Ma, Ke; Blaabjerg, Frede

2011-01-01

Several promising multi-level converter configurations for 10 MW Wind Turbines both with direct drive and one-stage gear box drive using Permanent Magnet Synchronous Generator (PMSG) are proposed, designed and compared. Reliability is a crucial indicator for large scale wind power converters...... that the three-level and five-level H-bridge converter topologies both have potential to achieve improved thermal performances compared to the three-level Neutral-Point-Clamped converter topology in the wind power application....

Multilevel Monte Carlo in Approximate Bayesian Computation

KAUST Repository

Jasra, Ajay

2017-02-13

In the following article we consider approximate Bayesian computation (ABC) inference. We introduce a method for numerically approximating ABC posteriors using the multilevel Monte Carlo (MLMC). A sequential Monte Carlo version of the approach is developed and it is shown under some assumptions that for a given level of mean square error, this method for ABC has a lower cost than i.i.d. sampling from the most accurate ABC approximation. Several numerical examples are given.

Tabu search approaches for the multi-level warehouse layout problem with adjacency constraints

Science.gov (United States)

Zhang, G. Q.; Lai, K. K.

2010-08-01

A new multi-level warehouse layout problem, the multi-level warehouse layout problem with adjacency constraints (MLWLPAC), is investigated. The same item type is required to be located in adjacent cells, and horizontal and vertical unit travel costs are product dependent. An integer programming model is proposed to formulate the problem, which is NP hard. Along with a cube-per-order index policy based heuristic, the standard tabu search (TS), greedy TS, and dynamic neighbourhood based TS are presented to solve the problem. The computational results show that the proposed approaches can reduce the transportation cost significantly.

A Dynamic Multi-Level Factor Model with Long-Range Dependence

DEFF Research Database (Denmark)

Ergemen, Yunus Emre; Rodríguez-Caballero, Carlos Vladimir

A dynamic multi-level factor model with stationary or nonstationary global and regional factors is proposed. In the model, persistence in global and regional common factors as well as innovations allows for the study of fractional cointegrating relationships. Estimation of global and regional...

Optimal algebraic multilevel preconditioning for local refinement along a line

NARCIS (Netherlands)

Margenov, S.D.; Maubach, J.M.L.

1995-01-01

The application of some recently proposed algebraic multilevel methods for the solution of two-dimensional finite element problems on nonuniform meshes is studied. The locally refined meshes are created by the newest vertex mesh refinement method. After the introduction of this refinement technique