Sample records for factor analysis applied

  1. Exploratory Factor Analysis as a Construct Validation Tool: (Mis)applications in Applied Linguistics Research

    ERIC Educational Resources Information Center

    Karami, Hossein

    2015-01-01

    Factor analysis has been frequently exploited in applied research to provide evidence about the underlying factors in various measurement instruments. A close inspection of a large number of studies published in leading applied linguistic journals shows that there is a misconception among applied linguists as to the relative merits of exploratory…

  2. Text mining factor analysis (TFA) in green tea patent data

    NASA Astrophysics Data System (ADS)

    Rahmawati, Sela; Suprijadi, Jadi; Zulhanif

    2017-03-01

    Factor analysis has become one of the most widely used multivariate statistical procedures in applied research endeavors across a multitude of domains. There are two main types of analyses based on factor analysis: Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). Both EFA and CFA aim to observed relationships among a group of indicators with a latent variable, but they differ fundamentally, a priori and restrictions made to the factor model. This method will be applied to patent data technology sector green tea to determine the development technology of green tea in the world. Patent analysis is useful in identifying the future technological trends in a specific field of technology. Database patent are obtained from agency European Patent Organization (EPO). In this paper, CFA model will be applied to the nominal data, which obtain from the presence absence matrix. While doing processing, analysis CFA for nominal data analysis was based on Tetrachoric matrix. Meanwhile, EFA model will be applied on a title from sector technology dominant. Title will be pre-processing first using text mining analysis.

  3. Confirmatory Factor Analysis of the Delirium Rating Scale Revised-98 (DRS-R98).

    PubMed

    Thurber, Steven; Kishi, Yasuhiro; Trzepacz, Paula T; Franco, Jose G; Meagher, David J; Lee, Yanghyun; Kim, Jeong-Lan; Furlanetto, Leticia M; Negreiros, Daniel; Huang, Ming-Chyi; Chen, Chun-Hsin; Kean, Jacob; Leonard, Maeve

    2015-01-01

    Principal components analysis applied to the Delirium Rating Scale-Revised-98 contributes to understanding the delirium construct. Using a multisite pooled international delirium database, the authors applied confirmatory factor analysis to Delirium Rating Scale-Revised-98 scores from 859 adult patients evaluated by delirium experts (delirium, N=516; nondelirium, N=343). Confirmatory factor analysis found all diagnostic features and core symptoms (cognitive, language, thought process, sleep-wake cycle, motor retardation), except motor agitation, loaded onto factor 1. Motor agitation loaded onto factor 2 with noncore symptoms (delusions, affective lability, and perceptual disturbances). Factor 1 loading supports delirium as a single construct, but when accompanied by psychosis, motor agitation's role may not be solely as a circadian activity indicator.

  4. Bayesian Exploratory Factor Analysis

    PubMed Central

    Conti, Gabriella; Frühwirth-Schnatter, Sylvia; Heckman, James J.; Piatek, Rémi

    2014-01-01

    This paper develops and applies a Bayesian approach to Exploratory Factor Analysis that improves on ad hoc classical approaches. Our framework relies on dedicated factor models and simultaneously determines the number of factors, the allocation of each measurement to a unique factor, and the corresponding factor loadings. Classical identification criteria are applied and integrated into our Bayesian procedure to generate models that are stable and clearly interpretable. A Monte Carlo study confirms the validity of the approach. The method is used to produce interpretable low dimensional aggregates from a high dimensional set of psychological measurements. PMID:25431517

  5. A New, More Powerful Approach to Multitrait-Multimethod Analyses: An Application of Second-Order Confirmatory Factor Analysis.

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Hocevar, Dennis

    The advantages of applying confirmatory factor analysis (CFA) to multitrait-multimethod (MTMM) data are widely recognized. However, because CFA as traditionally applied to MTMM data incorporates single indicators of each scale (i.e., each trait/method combination), important weaknesses are the failure to: (1) correct appropriately for measurement…

  6. Multiscale permutation entropy analysis of electrocardiogram

    NASA Astrophysics Data System (ADS)

    Liu, Tiebing; Yao, Wenpo; Wu, Min; Shi, Zhaorong; Wang, Jun; Ning, Xinbao

    2017-04-01

    To make a comprehensive nonlinear analysis to ECG, multiscale permutation entropy (MPE) was applied to ECG characteristics extraction to make a comprehensive nonlinear analysis of ECG. Three kinds of ECG from PhysioNet database, congestive heart failure (CHF) patients, healthy young and elderly subjects, are applied in this paper. We set embedding dimension to 4 and adjust scale factor from 2 to 100 with a step size of 2, and compare MPE with multiscale entropy (MSE). As increase of scale factor, MPE complexity of the three ECG signals are showing first-decrease and last-increase trends. When scale factor is between 10 and 32, complexities of the three ECG had biggest difference, entropy of the elderly is 0.146 less than the CHF patients and 0.025 larger than the healthy young in average, in line with normal physiological characteristics. Test results showed that MPE can effectively apply in ECG nonlinear analysis, and can effectively distinguish different ECG signals.

  7. Analysis and Design of Power Factor Pre-Regulator Based on a Symmetrical Charge Pump Circuit Applied to Electronic Ballast

    NASA Astrophysics Data System (ADS)

    Lazcano Olea, Miguel; Ramos Astudillo, Reynaldo; Sanhueza Robles, René; Rodriguez Rubke, Leopoldo; Ruiz-Caballero, Domingo Antonio

    This paper presents the analysis and design of a power factor pre-regulator based on a symmetrical charge pump circuit applied to electronic ballast. The operation stages of the circuit are analyzed and its main design equations are obtained. Simulation and experimental results are presented in order to show the design methodology feasibility.

  8. Item Factor Analysis: Current Approaches and Future Directions

    ERIC Educational Resources Information Center

    Wirth, R. J.; Edwards, Michael C.

    2007-01-01

    The rationale underlying factor analysis applies to continuous and categorical variables alike; however, the models and estimation methods for continuous (i.e., interval or ratio scale) data are not appropriate for item-level data that are categorical in nature. The authors provide a targeted review and synthesis of the item factor analysis (IFA)…

  9. Applying Cognitive Work Analysis to Time Critical Targeting Functionality

    DTIC Science & Technology

    2004-10-01

    Cognitive Task Analysis , CTA, Cognitive Task Analysis , Human Factors, GUI, Graphical User Interface, Heuristic Evaluation... Cognitive Task Analysis MITRE Briefing January 2000 Dynamic Battle Management Functional Architecture 3-1 Section 3 Human Factors...clear distinction between Cognitive Work Analysis (CWA) and Cognitive Task Analysis (CTA), therefore this document will refer to these

  10. Old and New Ideas for Data Screening and Assumption Testing for Exploratory and Confirmatory Factor Analysis

    PubMed Central

    Flora, David B.; LaBrish, Cathy; Chalmers, R. Philip

    2011-01-01

    We provide a basic review of the data screening and assumption testing issues relevant to exploratory and confirmatory factor analysis along with practical advice for conducting analyses that are sensitive to these concerns. Historically, factor analysis was developed for explaining the relationships among many continuous test scores, which led to the expression of the common factor model as a multivariate linear regression model with observed, continuous variables serving as dependent variables, and unobserved factors as the independent, explanatory variables. Thus, we begin our paper with a review of the assumptions for the common factor model and data screening issues as they pertain to the factor analysis of continuous observed variables. In particular, we describe how principles from regression diagnostics also apply to factor analysis. Next, because modern applications of factor analysis frequently involve the analysis of the individual items from a single test or questionnaire, an important focus of this paper is the factor analysis of items. Although the traditional linear factor model is well-suited to the analysis of continuously distributed variables, commonly used item types, including Likert-type items, almost always produce dichotomous or ordered categorical variables. We describe how relationships among such items are often not well described by product-moment correlations, which has clear ramifications for the traditional linear factor analysis. An alternative, non-linear factor analysis using polychoric correlations has become more readily available to applied researchers and thus more popular. Consequently, we also review the assumptions and data-screening issues involved in this method. Throughout the paper, we demonstrate these procedures using an historic data set of nine cognitive ability variables. PMID:22403561

  11. Hierarchical Factoring Based On Image Analysis And Orthoblique Rotations.

    PubMed

    Stankov, L

    1979-07-01

    The procedure for hierarchical factoring suggested by Schmid and Leiman (1957) is applied within the framework of image analysis and orthoblique rotational procedures. It is shown that this approach necessarily leads to correlated higher order factors. Also, one can obtain a smaller number of factors than produced by typical hierarchical procedures.

  12. A Primer on Bootstrap Factor Analysis as Applied to Health Studies Research

    ERIC Educational Resources Information Center

    Lu, Wenhua; Miao, Jingang; McKyer, E. Lisako J.

    2014-01-01

    Objectives: To demonstrate how the bootstrap method could be conducted in exploratory factor analysis (EFA) with a syntax written in SPSS. Methods: The data obtained from the Texas Childhood Obesity Prevention Policy Evaluation project (T-COPPE project) were used for illustration. A 5-step procedure to conduct bootstrap factor analysis (BFA) was…

  13. Impact of "JOBM": ISI Impact Factor Places the "Journal of Organizational Behavior Management" Third in Applied Psychology

    ERIC Educational Resources Information Center

    Hantula, Donald A.

    2006-01-01

    The ISI Impact Factor for "JOBM" is 1.793, placing it third in the JCR rankings for journals in applied psychology with a sharply accelerating linear trend over the past 5 years. This article reviews the Impact Factor and raises questions regarding its reliability and validity and then considers a citation analysis of "JOBM" in light of the…

  14. Analyse Factorielle d'une Batterie de Tests de Comprehension Orale et Ecrite (Factor Analysis of a Battery of Tests of Listening and Reading Comprehension). Melanges Pedagogiques, 1971.

    ERIC Educational Resources Information Center

    Lonchamp, F.

    This is a presentation of the results of a factor analysis of a battery of tests intended to measure listening and reading comprehension in English as a second language. The analysis sought to answer the following questions: (1) whether the factor analysis method yields results when applied to tests which are not specifically designed for this…

  15. Implementation of MCA Method for Identification of Factors for Conceptual Cost Estimation of Residential Buildings

    NASA Astrophysics Data System (ADS)

    Juszczyk, Michał; Leśniak, Agnieszka; Zima, Krzysztof

    2013-06-01

    Conceptual cost estimation is important for construction projects. Either underestimation or overestimation of building raising cost may lead to failure of a project. In the paper authors present application of a multicriteria comparative analysis (MCA) in order to select factors influencing residential building raising cost. The aim of the analysis is to indicate key factors useful in conceptual cost estimation in the early design stage. Key factors are being investigated on basis of the elementary information about the function, form and structure of the building, and primary assumptions of technological and organizational solutions applied in construction process. The mentioned factors are considered as variables of the model which aim is to make possible conceptual cost estimation fast and with satisfying accuracy. The whole analysis included three steps: preliminary research, choice of a set of potential variables and reduction of this set to select the final set of variables. Multicriteria comparative analysis is applied in problem solution. Performed analysis allowed to select group of factors, defined well enough at the conceptual stage of the design process, to be used as a describing variables of the model.

  16. Risky Business: Factor Analysis of Survey Data – Assessing the Probability of Incorrect Dimensionalisation

    PubMed Central

    van der Eijk, Cees; Rose, Jonathan

    2015-01-01

    This paper undertakes a systematic assessment of the extent to which factor analysis the correct number of latent dimensions (factors) when applied to ordered-categorical survey items (so-called Likert items). We simulate 2400 data sets of uni-dimensional Likert items that vary systematically over a range of conditions such as the underlying population distribution, the number of items, the level of random error, and characteristics of items and item-sets. Each of these datasets is factor analysed in a variety of ways that are frequently used in the extant literature, or that are recommended in current methodological texts. These include exploratory factor retention heuristics such as Kaiser’s criterion, Parallel Analysis and a non-graphical scree test, and (for exploratory and confirmatory analyses) evaluations of model fit. These analyses are conducted on the basis of Pearson and polychoric correlations. We find that, irrespective of the particular mode of analysis, factor analysis applied to ordered-categorical survey data very often leads to over-dimensionalisation. The magnitude of this risk depends on the specific way in which factor analysis is conducted, the number of items, the properties of the set of items, and the underlying population distribution. The paper concludes with a discussion of the consequences of over-dimensionalisation, and a brief mention of alternative modes of analysis that are much less prone to such problems. PMID:25789992

  17. Usage of K-cluster and factor analysis for grouping and evaluation the quality of olive oil in accordance with physico-chemical parameters

    NASA Astrophysics Data System (ADS)

    Milev, M.; Nikolova, Kr.; Ivanova, Ir.; Dobreva, M.

    2015-11-01

    25 olive oils were studied- different in origin and ways of extraction, in accordance with 17 physico-chemical parameters as follows: color parameters - a and b, light, fluorescence peaks, pigments - chlorophyll and β-carotene, fatty-acid content. The goals of the current study were: Conducting correlation analysis to find the inner relation between the studied indices; By applying factor analysis with the help of the method of Principal Components (PCA), to reduce the great number of variables into a few factors, which are of main importance for distinguishing the different types of olive oil;Using K-means cluster to compare and group the tested types olive oils based on their similarity. The inner relation between the studied indices was found by applying correlation analysis. A factor analysis using PCA was applied on the basis of the found correlation matrix. Thus the number of the studied indices was reduced to 4 factors, which explained 79.3% from the entire variation. The first one unified the color parameters, β-carotene and the related with oxidative products fluorescence peak - about 520 nm. The second one was determined mainly by the chlorophyll content and related to it fluorescence peak - about 670 nm. The third and the fourth factors were determined by the fatty-acid content of the samples. The third one unified the fatty-acids, which give us the opportunity to distinguish olive oil from the other plant oils - oleic, linoleic and stearin acids. The fourth factor included fatty-acids with relatively much lower content in the studied samples. It is enquired the number of clusters to be determined preliminary in order to apply the K-Cluster analysis. The variant K = 3 was worked out because the types of the olive oil were three. The first cluster unified all salad and pomace olive oils, the second unified the samples of extra virgin oilstaken as controls from producers, which were bought from the trade network. The third cluster unified samples from pomace and extra virgin oils, which distinguish one from another in accordance with their parameters from the natural olive oils, because of presence of plant oils impurities.

  18. Applying a Danish Version of the Learning Transfer System Inventory and Testing It for Different Types of Education

    ERIC Educational Resources Information Center

    Soerensen, Peter; Stegeager, Nikolaj; Bates, Reid

    2017-01-01

    The purpose of this study was to answer two research questions. First, will an exploratory factor analysis of a Danish version of the Learning Transfer System Inventory (LTSI) result in a factor structure which is consistent with the original American LTSI factor structure? Second, does the mean score in the factor analysis vary in a statistically…

  19. Applied Statistics: From Bivariate through Multivariate Techniques [with CD-ROM

    ERIC Educational Resources Information Center

    Warner, Rebecca M.

    2007-01-01

    This book provides a clear introduction to widely used topics in bivariate and multivariate statistics, including multiple regression, discriminant analysis, MANOVA, factor analysis, and binary logistic regression. The approach is applied and does not require formal mathematics; equations are accompanied by verbal explanations. Students are asked…

  20. Communication Network Analysis Methods.

    ERIC Educational Resources Information Center

    Farace, Richard V.; Mabee, Timothy

    This paper reviews a variety of analytic procedures that can be applied to network data, discussing the assumptions and usefulness of each procedure when applied to the complexity of human communication. Special attention is paid to the network properties measured or implied by each procedure. Factor analysis and multidimensional scaling are among…

  1. An Empirical Analysis of Chinese College Learners' Obstacles to MOOC Learning in an English Context

    ERIC Educational Resources Information Center

    Liu, Liangxing

    2017-01-01

    This article reports a study applying an exploratory factor analysis to discovering the underlying factor structure of Chinese college students' obstacles to learning MOOC in an English context. Seven obstacle factors are identified: 1. academic and language skills; 2. internet skills; 3. course instruction/management; 4. learning motivations; 5.…

  2. Factor analysis of an instrument to measure the impact of disease on daily life.

    PubMed

    Pedrosa, Rafaela Batista Dos Santos; Rodrigues, Roberta Cunha Matheus; Padilha, Kátia Melissa; Gallani, Maria Cecília Bueno Jayme; Alexandre, Neusa Maria Costa

    2016-01-01

    to verify the structure of factors of an instrument to measure the Heart Valve Disease Impact on Daily Life (IDCV) when applied to coronary artery disease patients. the study included 153 coronary artery disease patients undergoing outpatient follow-up care. The IDCV structure of factors was initially assessed by means of confirmatory factor analysis and, subsequently, by exploratory factor analysis. The Varimax rotation method was used to estimate the main components of analysis, eigenvalues greater than one for extraction of factors, and factor loading greater than 0.40 for selection of items. Internal consistency was estimated using Cronbach's alpha coefficient. confirmatory factor analysis did not confirm the original structure of factors of the IDCV. Exploratory factor analysis showed three dimensions, which together explained 78% of the measurement variance. future studies with expansion of case selection are necessary to confirm the IDCV new structure of factors.

  3. Metropolis-Hastings Robbins-Monro Algorithm for Confirmatory Item Factor Analysis

    ERIC Educational Resources Information Center

    Cai, Li

    2010-01-01

    Item factor analysis (IFA), already well established in educational measurement, is increasingly applied to psychological measurement in research settings. However, high-dimensional confirmatory IFA remains a numerical challenge. The current research extends the Metropolis-Hastings Robbins-Monro (MH-RM) algorithm, initially proposed for…

  4. Data analysis strategies for reducing the influence of the bias in cross-cultural research.

    PubMed

    Sindik, Josko

    2012-03-01

    In cross-cultural research, researchers have to adjust the constructs and associated measurement instruments that have been developed in one culture and then imported for use in another culture. Importing concepts from other cultures is often simply reduced to language adjustment of the content in the items of the measurement instruments that define a certain (psychological) construct. In the context of cross-cultural research, test bias can be defined as a generic term for all nuisance factors that threaten the validity of cross-cultural comparisons. Bias can be an indicator that instrument scores based on the same items measure different traits and characteristics across different cultural groups. To reduce construct, method and item bias,the researcher can consider these strategies: (1) simply comparing average results in certain measuring instruments; (2) comparing only the reliability of certain dimensions of the measurement instruments, applied to the "target" and "source" samples of participants, i.e. from different cultures; (3) comparing the "framed" factor structure (fixed number of factors) of the measurement instruments, applied to the samples from the "target" and "source" cultures, using explorative factor analysis strategy on separate samples; (4) comparing the complete constructs ("unframed" factor analysis, i.e. unlimited number of factors) in relation to their best psychometric properties and the possibility of interpreting (best suited to certain cultures, applying explorative strategy of factor analysis); or (5) checking the similarity of the constructs in the samples from different cultures (using structural equation modeling approach). Each approach has its advantages and disadvantages. The advantages and lacks of each approach are discussed.

  5. A Confirmatory Factor Analysis of the Student Evidence-Based Practice Questionnaire (S-EBPQ) in an Australian sample.

    PubMed

    Beccaria, Lisa; Beccaria, Gavin; McCosker, Catherine

    2018-03-01

    It is crucial that nursing students develop skills and confidence in using Evidence-Based Practice principles early in their education. This should be assessed with valid tools however, to date, few measures have been developed and applied to the student population. To examine the structural validity of the Student Evidence-Based Practice Questionnaire (S-EBPQ), with an Australian online nursing student cohort. A cross-sectional study for constructing validity. Three hundred and forty-five undergraduate nursing students from an Australian regional university were recruited across two semesters. Confirmatory Factor Analysis was used to examine the structural validity. Confirmatory Factor Analysis was applied which resulted in a good fitting model, based on a revised 20-item tool. The S-EBPQ tool remains a psychometrically robust measure of evidence-based practice use, attitudes, and knowledge and skills and can be applied in an online Australian student context. The findings of this study provided further evidence of the reliability and four factor structure of the S-EBPQ. Opportunities for further refinement of the tool may result in improvements in structural validity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Multivariate Statistical Analysis of MSL APXS Bulk Geochemical Data

    NASA Astrophysics Data System (ADS)

    Hamilton, V. E.; Edwards, C. S.; Thompson, L. M.; Schmidt, M. E.

    2014-12-01

    We apply cluster and factor analyses to bulk chemical data of 130 soil and rock samples measured by the Alpha Particle X-ray Spectrometer (APXS) on the Mars Science Laboratory (MSL) rover Curiosity through sol 650. Multivariate approaches such as principal components analysis (PCA), cluster analysis, and factor analysis compliment more traditional approaches (e.g., Harker diagrams), with the advantage of simultaneously examining the relationships between multiple variables for large numbers of samples. Principal components analysis has been applied with success to APXS, Pancam, and Mössbauer data from the Mars Exploration Rovers. Factor analysis and cluster analysis have been applied with success to thermal infrared (TIR) spectral data of Mars. Cluster analyses group the input data by similarity, where there are a number of different methods for defining similarity (hierarchical, density, distribution, etc.). For example, without any assumptions about the chemical contributions of surface dust, preliminary hierarchical and K-means cluster analyses clearly distinguish the physically adjacent rock targets Windjana and Stephen as being distinctly different than lithologies observed prior to Curiosity's arrival at The Kimberley. In addition, they are separated from each other, consistent with chemical trends observed in variation diagrams but without requiring assumptions about chemical relationships. We will discuss the variation in cluster analysis results as a function of clustering method and pre-processing (e.g., log transformation, correction for dust cover) and implications for interpreting chemical data. Factor analysis shares some similarities with PCA, and examines the variability among observed components of a dataset so as to reveal variations attributable to unobserved components. Factor analysis has been used to extract the TIR spectra of components that are typically observed in mixtures and only rarely in isolation; there is the potential for similar results with data from APXS. These techniques offer new ways to understand the chemical relationships between the materials interrogated by Curiosity, and potentially their relation to materials observed by APXS instruments on other landed missions.

  7. System for corrosion monitoring in pipeline applying fuzzy logic mathematics

    NASA Astrophysics Data System (ADS)

    Kuzyakov, O. N.; Kolosova, A. L.; Andreeva, M. A.

    2018-05-01

    A list of factors influencing corrosion rate on the external side of underground pipeline is determined. Principles of constructing a corrosion monitoring system are described; the system performance algorithm and program are elaborated. A comparative analysis of methods for calculating corrosion rate is undertaken. Fuzzy logic mathematics is applied to reduce calculations while considering a wider range of corrosion factors.

  8. 40 CFR 1039.245 - How do I determine deterioration factors from exhaust durability testing?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... with an engineering analysis, with pre-existing test data, or with new emission measurements. Apply... factors for an engine family with established technology based on engineering analysis instead of testing... an engine family under paragraph (a) or (b) of this section, select engines, subsystems, or...

  9. 40 CFR 1039.245 - How do I determine deterioration factors from exhaust durability testing?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... with an engineering analysis, with pre-existing test data, or with new emission measurements. Apply... factors for an engine family with established technology based on engineering analysis instead of testing... an engine family under paragraph (a) or (b) of this section, select engines, subsystems, or...

  10. 40 CFR 1039.245 - How do I determine deterioration factors from exhaust durability testing?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... with an engineering analysis, with pre-existing test data, or with new emission measurements. Apply... factors for an engine family with established technology based on engineering analysis instead of testing... an engine family under paragraph (a) or (b) of this section, select engines, subsystems, or...

  11. 40 CFR 1039.245 - How do I determine deterioration factors from exhaust durability testing?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... with an engineering analysis, with pre-existing test data, or with new emission measurements. Apply... factors for an engine family with established technology based on engineering analysis instead of testing... an engine family under paragraph (a) or (b) of this section, select engines, subsystems, or...

  12. 40 CFR 1039.245 - How do I determine deterioration factors from exhaust durability testing?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... with an engineering analysis, with pre-existing test data, or with new emission measurements. Apply... factors for an engine family with established technology based on engineering analysis instead of testing... an engine family under paragraph (a) or (b) of this section, select engines, subsystems, or...

  13. Factor Analysis by Generalized Least Squares.

    ERIC Educational Resources Information Center

    Joreskog, Karl G.; Goldberger, Arthur S.

    Aitkin's generalized least squares (GLS) principle, with the inverse of the observed variance-covariance matrix as a weight matrix, is applied to estimate the factor analysis model in the exploratory (unrestricted) case. It is shown that the GLS estimates are scale free and asymptotically efficient. The estimates are computed by a rapidly…

  14. [PROGNOSTIC MODELS IN MODERN MANAGEMENT OF VULVAR CANCER].

    PubMed

    Tsvetkov, Ch; Gorchev, G; Tomov, S; Nikolova, M; Genchev, G

    2016-01-01

    The aim of the research was to evaluate and analyse prognosis and prognostic factors in patients with squamous cell vulvar carcinoma after primary surgery with individual approach applied during the course of treatment. In the period between January 2000 and July 2010, 113 patients with squamous cell carcinoma of the vulva were diagnosed and operated on at Gynecologic Oncology Clinic of Medical University, Pleven. All the patients were monitored at the same clinic. Individual approach was applied to each patient and whenever it was possible, more conservative operative techniques were applied. The probable clinicopathological characteristics influencing the overall survival and recurrence free survival were analyzed. Univariate statistical analysis and Cox regression analysis were made in order to evaluate the characteristics, which were statistically significant for overall survival and survival without recurrence. A multivariate logistic regression analysis (Forward Wald procedure) was applied to evaluate the combined influence of the significant factors. While performing the multivariate analysis, the synergic effect of the independent prognostic factors of both kinds of survivals was also evaluated. Approaching individually each patient, we applied the following operative techniques: 1. Deep total radical vulvectomy with separate incisions for lymph dissection (LD) or without dissection--68 (60.18 %) patients. 2. En-bloc vulvectomy with bilateral LD without vulva reconstruction--10 (8.85%) 3. Modified radical vulvactomy (hemivulvectomy, patial vulvactomy)--25 (22.02%). 4. wide-local excision--3 (2.65%). 5. Simple (total /partial) vulvectomy--5 (4.43%) patients. 6. En-bloc resection with reconstruction--2 (1.77%) After a thorough analysis of the overall survival and recurrence free survival, we made the conclusion that the relapse occurrence and clinical stage of FIGO were independent prognostic factors for overall survival and the independent prognostic factors for recurrence free survival were: metastatic inguinal nodes (unilateral or bilateral), tumor size (above or below 3 cm) and lymphovascular space invasion. On the basis of these results we created two prognostic models: 1. A prognostic model of overall survival 2. A prognostic model for survival without recurrence. Following the surgical staging of the disease, were able to gather and analyse important clinicopathological indexes, which gave us the opportunity to form prognostic groups for overall survival and recurrence-free survival.

  15. Validation of the Child and Youth Resilience Measure (CYRM-28) on a Sample of At-Risk New Zealand Youth

    ERIC Educational Resources Information Center

    Sanders, Jackie; Munford, Robyn; Thimasarn-Anwar, Tewaporn; Liebenberg, Linda

    2017-01-01

    Purpose: This article reports on an examination of the psychometric properties of the 28-item Child and Youth Resilience Measure (CYRM-28). Methods: Exploratory factor analysis, confirmatory factor analysis, Cronbach's a, "t"-tests, correlations, and multivariate analysis of variance were applied to data collected via interviews from 593…

  16. UK Parents' Beliefs about Applied Behaviour Analysis as an Approach to Autism Education

    ERIC Educational Resources Information Center

    Denne, Louise D.; Hastings, Richard P.; Hughes, J. Carl

    2017-01-01

    Research into factors underlying the dissemination of evidence-based practice is limited within the field of Applied Behaviour Analysis (ABA). This is pertinent, particularly in the UK where national policies and guidelines do not reflect the emerging ABA evidence base, or policies and practices elsewhere. Theories of evidence-based practice in…

  17. The Meaning of Higher-Order Factors in Reflective-Measurement Models

    ERIC Educational Resources Information Center

    Eid, Michael; Koch, Tobias

    2014-01-01

    Higher-order factor analysis is a widely used approach for analyzing the structure of a multidimensional test. Whenever first-order factors are correlated researchers are tempted to apply a higher-order factor model. But is this reasonable? What do the higher-order factors measure? What is their meaning? Willoughby, Holochwost, Blanton, and Blair…

  18. Application of Factor Analysis on the Financial Ratios of Indian Cement Industry and Validation of the Results by Cluster Analysis

    NASA Astrophysics Data System (ADS)

    De, Anupam; Bandyopadhyay, Gautam; Chakraborty, B. N.

    2010-10-01

    Financial ratio analysis is an important and commonly used tool in analyzing financial health of a firm. Quite a large number of financial ratios, which can be categorized in different groups, are used for this analysis. However, to reduce number of ratios to be used for financial analysis and regrouping them into different groups on basis of empirical evidence, Factor Analysis technique is being used successfully by different researches during the last three decades. In this study Factor Analysis has been applied over audited financial data of Indian cement companies for a period of 10 years. The sample companies are listed on the Stock Exchange India (BSE and NSE). Factor Analysis, conducted over 44 variables (financial ratios) grouped in 7 categories, resulted in 11 underlying categories (factors). Each factor is named in an appropriate manner considering the factor loads and constituent variables (ratios). Representative ratios are identified for each such factor. To validate the results of Factor Analysis and to reach final conclusion regarding the representative ratios, Cluster Analysis had been performed.

  19. Configurations of Common Childhood Psychosocial Risk Factors

    ERIC Educational Resources Information Center

    Copeland, William; Shanahan, Lilly; Costello, E. Jane; Angold, Adrian

    2009-01-01

    Background: Co-occurrence of psychosocial risk factors is commonplace, but little is known about psychiatrically-predictive configurations of psychosocial risk factors. Methods: Latent class analysis (LCA) was applied to 17 putative psychosocial risk factors in a representative population sample of 920 children ages 9 to 17. The resultant class…

  20. Human Factors Process Task Analysis: Liquid Oxygen Pump Acceptance Test Procedure at the Advanced Technology Development Center

    NASA Technical Reports Server (NTRS)

    Diorio, Kimberly A.; Voska, Ned (Technical Monitor)

    2002-01-01

    This viewgraph presentation provides information on Human Factors Process Failure Modes and Effects Analysis (HF PFMEA). HF PFMEA includes the following 10 steps: Describe mission; Define System; Identify human-machine; List human actions; Identify potential errors; Identify factors that effect error; Determine likelihood of error; Determine potential effects of errors; Evaluate risk; Generate solutions (manage error). The presentation also describes how this analysis was applied to a liquid oxygen pump acceptance test.

  1. Heisenberg principle applied to the analysis of speckle interferometry fringes

    NASA Astrophysics Data System (ADS)

    Sciammarella, C. A.; Sciammarella, F. M.

    2003-11-01

    Optical techniques that are used to measure displacements utilize a carrier. When a load is applied the displacement field modulates the carrier. The accuracy of the information that can be recovered from the modulated carrier is limited by a number of factors. In this paper, these factors are analyzed and conclusions concerning the limitations in information recovery are illustrated with examples taken from experimental data.

  2. Exploratory Bi-factor Analysis: The Oblique Case.

    PubMed

    Jennrich, Robert I; Bentler, Peter M

    2012-07-01

    Bi-factor analysis is a form of confirmatory factor analysis originally introduced by Holzinger and Swineford (Psychometrika 47:41-54, 1937). The bi-factor model has a general factor, a number of group factors, and an explicit bi-factor structure. Jennrich and Bentler (Psychometrika 76:537-549, 2011) introduced an exploratory form of bi-factor analysis that does not require one to provide an explicit bi-factor structure a priori. They use exploratory factor analysis and a bifactor rotation criterion designed to produce a rotated loading matrix that has an approximate bi-factor structure. Among other things this can be used as an aid in finding an explicit bi-factor structure for use in a confirmatory bi-factor analysis. They considered only orthogonal rotation. The purpose of this paper is to consider oblique rotation and to compare it to orthogonal rotation. Because there are many more oblique rotations of an initial loading matrix than orthogonal rotations, one expects the oblique results to approximate a bi-factor structure better than orthogonal rotations and this is indeed the case. A surprising result arises when oblique bi-factor rotation methods are applied to ideal data.

  3. Structural Equation Analysis of the Wechsler Adult Intelligence Scale-Revised in a Normal Elderly Sample.

    ERIC Educational Resources Information Center

    Burton, D. Bradley; And Others

    1994-01-01

    A maximum-likelihood confirmatory factor analysis was performed by applying LISREL VII to the Wechsler Adult Intelligence Scale-Revised results of a normal elderly sample of 225 adults. Results indicate that a three-factor model fits best across all sample combinations. A mild gender effect is discussed. (SLD)

  4. Systems thinking applied to safety during manual handling tasks in the transport and storage industry.

    PubMed

    Goode, Natassia; Salmon, Paul M; Lenné, Michael G; Hillard, Peter

    2014-07-01

    Injuries resulting from manual handling tasks represent an on-going problem for the transport and storage industry. This article describes an application of a systems theory-based approach, Rasmussen's (1997. Safety Science 27, 183), risk management framework, to the analysis of the factors influencing safety during manual handling activities in a freight handling organisation. Observations of manual handling activities, cognitive decision method interviews with workers (n=27) and interviews with managers (n=35) were used to gather information about three manual handling activities. Hierarchical task analysis and thematic analysis were used to identify potential risk factors and performance shaping factors across the levels of Rasmussen's framework. These different data sources were then integrated using Rasmussen's Accimap technique to provide an overall analysis of the factors influencing safety during manual handling activities in this context. The findings demonstrate how a systems theory-based approach can be applied to this domain, and suggest that policy-orientated, rather than worker-orientated, changes are required to prevent future manual handling injuries. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Protein Structure Prediction with Evolutionary Algorithms

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

    Hart, W.E.; Krasnogor, N.; Pelta, D.A.

    1999-02-08

    Evolutionary algorithms have been successfully applied to a variety of molecular structure prediction problems. In this paper we reconsider the design of genetic algorithms that have been applied to a simple protein structure prediction problem. Our analysis considers the impact of several algorithmic factors for this problem: the confirmational representation, the energy formulation and the way in which infeasible conformations are penalized, Further we empirically evaluated the impact of these factors on a small set of polymer sequences. Our analysis leads to specific recommendations for both GAs as well as other heuristic methods for solving PSP on the HP model.

  6. Risk analysis of the thermal sterilization process. Analysis of factors affecting the thermal resistance of microorganisms.

    PubMed

    Akterian, S G; Fernandez, P S; Hendrickx, M E; Tobback, P P; Periago, P M; Martinez, A

    1999-03-01

    A risk analysis was applied to experimental heat resistance data. This analysis is an approach for processing experimental thermobacteriological data in order to study the variability of D and z values of target microorganisms depending on the deviations range of environmental factors, to determine the critical factors and to specify their critical tolerance. This analysis is based on sets of sensitivity functions applied to a specific case of experimental data related to the thermoresistance of Clostridium sporogenes and Bacillus stearothermophilus spores. The effect of the following factors was analyzed: the type of target microorganism; nature of the heating substrate; pH, temperature; type of acid employed and NaCl concentration. The type of target microorganism to be inactivated, the nature of the substrate (reference or real food) and the heating temperature were identified as critical factors, determining about 90% of the alteration of the microbiological risk. The effect of the type of acid used for the acidification of products and the concentration of NaCl can be assumed to be negligible factors for the purposes of engineering calculations. The critical non-uniformity in temperature during thermobacteriological studies was set as 0.5% and the critical tolerances of pH value and NaCl concentration were 5%. These results are related to a specific case study, for that reason their direct generalization is not correct.

  7. Improving social connection through a communities-of-practice-inspired cognitive work analysis approach.

    PubMed

    Euerby, Adam; Burns, Catherine M

    2014-03-01

    Increasingly, people work in socially networked environments. With growing adoption of enterprise social network technologies, supporting effective social community is becoming an important factor in organizational success. Relatively few human factors methods have been applied to social connection in communities. Although team methods provide a contribution, they do not suit design for communities. Wenger's community of practice concept, combined with cognitive work analysis, provided one way of designing for community. We used a cognitive work analysis approach modified with principles for supporting communities of practice to generate a new website design. Over several months, the community using the site was studied to examine their degree of social connectedness and communication levels. Social network analysis and communications analysis, conducted at three different intervals, showed increases in connections between people and between people and organizations, as well as increased communication following the launch of the new design. In this work, we suggest that human factors approaches can be effective in social environments, when applied considering social community principles. This work has implications for the development of new human factors methods as well as the design of interfaces for sociotechnical systems that have community building requirements.

  8. Evaluation of the Actuator Line Model with coarse resolutions

    NASA Astrophysics Data System (ADS)

    Draper, M.; Usera, G.

    2015-06-01

    The aim of the present paper is to evaluate the Actuator Line Model (ALM) in spatial resolutions coarser than what is generally recommended, also using larger time steps. To accomplish this, the ALM has been implemented in the open source code caffa3d.MBRi and validated against experimental measurements of two wind tunnel campaigns (stand alone wind turbine and two wind turbines in line, case A and B respectively), taking into account two spatial resolutions: R/8 and R/15 (R is the rotor radius). A sensitivity analysis in case A was performed in order to get some insight into the influence of the smearing factor (3D Gaussian distribution) and time step size in power and thrust, as well as in the wake, without applying a tip loss correction factor (TLCF), for one tip speed ratio (TSR). It is concluded that as the smearing factor is larger or time step size is smaller the power is increased, but the velocity deficit is not as much affected. From this analysis, a smearing factor was obtained in order to calculate precisely the power coefficient for that TSR without applying TLCF. Results with this approach were compared with another simulation choosing a larger smearing factor and applying Prandtl's TLCF, for three values of TSR. It is found that applying the TLCF improves the power estimation and weakens the influence of the smearing factor. Finally, these 2 alternatives were tested in case B, confirming that conclusion.

  9. Pharmaceutical strategic purchasing requirements in Iran: Price interventions and the related effective factors.

    PubMed

    Bastani, Peivand; Dinarvand, Rasoul; SamadBeik, Mahnaz; Pourmohammadi, Kimia

    2016-01-01

    Pharmaceutical access for the poor is an essential factor in developing countries that can be improved through strategic purchasing. This study was conducted to identify the elements affecting price in order to enable insurance organizations to put strategic purchasing into practice. This was a qualitative study conducted through content analysis with an inductive approach applying a five-stage framework analysis (familiarization, identifying a thematic framework, indexing, mapping, and interpretation). Data analysis was started right after transcribing each interview applying ATLAS.ti. Data were saturated after 32 semi-structured interviews by experts. These key informants were selected purposefully and through snowball sampling. Findings showed that there are four main themes as Pharmaceutical Strategic Purchasing Requirements in Iran as follows essential and structural factors, international factors, economical factors, and legal factors. Moreover, totally 14 related sub-themes were extracted in this area as the main effective variables. It seems that paying adequate attention to the four present themes and 14 sub-themes affecting price can enable health system policy-makers of developing countries like Iran to make the best decisions through strategic purchasing of drugs by the main insurers in order to improve access and health in the country.

  10. Comparative Analysis of English Language Student's School Paths at a Mexico University

    ERIC Educational Resources Information Center

    Robelo, Octaviano García; Marquez, Jorge Hernández; Pérez, Ileana Casasola

    2017-01-01

    Seven factors related to academic paths of students of the Bachelor of English Language of a public university in Mexico are investigated. With a non-experimental descriptive design, a Likert scale was applied to evaluate the college students' perception of these factors. A comparative analysis between three types of school paths was performed. It…

  11. An analysis of the ArcCHECK-MR diode array's performance for ViewRay quality assurance.

    PubMed

    Ellefson, Steven T; Culberson, Wesley S; Bednarz, Bryan P; DeWerd, Larry A; Bayouth, John E

    2017-07-01

    The ArcCHECK-MR diode array utilizes a correction system with a virtual inclinometer to correct the angular response dependencies of the diodes. However, this correction system cannot be applied to measurements on the ViewRay MR-IGRT system due to the virtual inclinometer's incompatibility with the ViewRay's multiple simultaneous beams. Additionally, the ArcCHECK's current correction factors were determined without magnetic field effects taken into account. In the course of performing ViewRay IMRT quality assurance with the ArcCHECK, measurements were observed to be consistently higher than the ViewRay TPS predictions. The goals of this study were to quantify the observed discrepancies and test whether applying the current factors improves the ArcCHECK's accuracy for measurements on the ViewRay. Gamma and frequency analysis were performed on 19 ViewRay patient plans. Ion chamber measurements were performed at a subset of diode locations using a PMMA phantom with the same dimensions as the ArcCHECK. A new method for applying directionally dependent factors utilizing beam information from the ViewRay TPS was developed in order to analyze the current ArcCHECK correction factors. To test the current factors, nine ViewRay plans were altered to be delivered with only a single simultaneous beam and were measured with the ArcCHECK. The current correction factors were applied using both the new and current methods. The new method was also used to apply corrections to the original 19 ViewRay plans. It was found the ArcCHECK systematically reports doses higher than those actually delivered by the ViewRay. Application of the current correction factors by either method did not consistently improve measurement accuracy. As dose deposition and diode response have both been shown to change under the influence of a magnetic field, it can be concluded the current ArcCHECK correction factors are invalid and/or inadequate to correct measurements on the ViewRay system. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  12. A comparison study on detection of key geochemical variables and factors through three different types of factor analysis

    NASA Astrophysics Data System (ADS)

    Hoseinzade, Zohre; Mokhtari, Ahmad Reza

    2017-10-01

    Large numbers of variables have been measured to explain different phenomena. Factor analysis has widely been used in order to reduce the dimension of datasets. Additionally, the technique has been employed to highlight underlying factors hidden in a complex system. As geochemical studies benefit from multivariate assays, application of this method is widespread in geochemistry. However, the conventional protocols in implementing factor analysis have some drawbacks in spite of their advantages. In the present study, a geochemical dataset including 804 soil samples collected from a mining area in central Iran in order to search for MVT type Pb-Zn deposits was considered to outline geochemical analysis through various fractal methods. Routine factor analysis, sequential factor analysis, and staged factor analysis were applied to the dataset after opening the data with (additive logratio) alr-transformation to extract mineralization factor in the dataset. A comparison between these methods indicated that sequential factor analysis has more clearly revealed MVT paragenesis elements in surface samples with nearly 50% variation in F1. In addition, staged factor analysis has given acceptable results while it is easy to practice. It could detect mineralization related elements while larger factor loadings are given to these elements resulting in better pronunciation of mineralization.

  13. Leuconostoc strains isolated from dairy products: Response against food stress conditions.

    PubMed

    D'Angelo, Luisa; Cicotello, Joaquín; Zago, Miriam; Guglielmotti, Daniela; Quiberoni, Andrea; Suárez, Viviana

    2017-09-01

    A systematic study about the intrinsic resistance of 29 strains (26 autochthonous and 3 commercial ones), belonging to Leuconostoc genus, against diverse stress factors (thermal, acidic, alkaline, osmotic and oxidative) commonly present at industrial or conservation processes were evaluated. Exhaustive result processing was made by applying one-way ANOVA, Student's test (t), multivariate analysis by Principal Component Analysis (PCA) and Matrix Hierarchical Cluster Analysis. In addition, heat adaptation on 4 strains carefully selected based on previous data analysis was assayed. The strains revealed wide diversity of resistance to stress factors and, in general, a clear relationship between resistance and Leuconostoc species was established. In this sense, the highest resistance was shown by Leuconostoc lactis followed by Leuconostoc mesenteroides strains, while Leuconostoc pseudomesenteroides and Leuconostoc citreum strains revealed the lowest resistance to the stress factors applied. Heat adaptation improved thermal cell survival and resulted in a cross-resistance against the acidic factor. However, all adapted cells showed diminished their oxidative resistance. According to our knowledge, this is the first study regarding response of Leuconostoc strains against technological stress factors and could establish the basis for the selection of "more robust" strains and propose the possibility of improving their performance during industrial processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Mortality and economic instability: detailed analyses for Britain and comparative analyses for selected industrialized countries.

    PubMed

    Brenner, M H

    1983-01-01

    This paper discusses a first-stage analysis of the link of unemployment rates, as well as other economic, social and environmental health risk factors, to mortality rates in postwar Britain. The results presented represent part of an international study of the impact of economic change on mortality patterns in industrialized countries. The mortality patterns examined include total and infant mortality and (by cause) cardiovascular (total), cerebrovascular and heart disease, cirrhosis of the liver, and suicide, homicide and motor vehicle accidents. Among the most prominent factors that beneficially influence postwar mortality patterns in England/Wales and Scotland are economic growth and stability and health service availability. A principal detrimental factor to health is a high rate of unemployment. Additional factors that have an adverse influence on mortality rates are cigarette consumption and heavy alcohol use and unusually cold winter temperatures (especially in Scotland). The model of mortality that includes both economic changes and behavioral and environmental risk factors was successfully applied to infant mortality rates in the interwar period. In addition, the "simple" economic change model of mortality (using only economic indicators) was applied to other industrialized countries. In Canada, the United States, the United Kingdom, and Sweden, the simple version of the economic change model could be successfully applied only if the analysis was begun before World War II; for analysis beginning in the postwar era, the more sophisticated economic change model, including behavioral and environmental risk factors, was required. In France, West Germany, Italy, and Spain, by contrast, some success was achieved using the simple economic change model.

  15. [Mathematic analysis of risk factors influence on occupational respiratory diseases development].

    PubMed

    Budkar', L N; Bugaeva, I V; Obukhova, T Iu; Tereshina, L G; Karpova, E A; Shmonina, O G

    2010-01-01

    Analysis covered 1348 case histories of workers exposed to industrial dust in Urals region. The analysis applied mathematical processing of survival theory and correlation analysis. The authors studied influence of various factors: dust concentration, connective tissue dysplasia, smoking habits--on duration for diseases caused by dust to appear. Findings are that occupational diseases develop reliably faster with higher ambient dust concentrations and with connective tissue dysplasia syndrome. Smoking habits do not alter duration of pneumoconiosis development, but reliably increases development of occupational dust bronchitis.

  16. Pathway-based factor analysis of gene expression data produces highly heritable phenotypes that associate with age.

    PubMed

    Anand Brown, Andrew; Ding, Zhihao; Viñuela, Ana; Glass, Dan; Parts, Leopold; Spector, Tim; Winn, John; Durbin, Richard

    2015-03-09

    Statistical factor analysis methods have previously been used to remove noise components from high-dimensional data prior to genetic association mapping and, in a guided fashion, to summarize biologically relevant sources of variation. Here, we show how the derived factors summarizing pathway expression can be used to analyze the relationships between expression, heritability, and aging. We used skin gene expression data from 647 twins from the MuTHER Consortium and applied factor analysis to concisely summarize patterns of gene expression to remove broad confounding influences and to produce concise pathway-level phenotypes. We derived 930 "pathway phenotypes" that summarized patterns of variation across 186 KEGG pathways (five phenotypes per pathway). We identified 69 significant associations of age with phenotype from 57 distinct KEGG pathways at a stringent Bonferroni threshold ([Formula: see text]). These phenotypes are more heritable ([Formula: see text]) than gene expression levels. On average, expression levels of 16% of genes within these pathways are associated with age. Several significant pathways relate to metabolizing sugars and fatty acids; others relate to insulin signaling. We have demonstrated that factor analysis methods combined with biological knowledge can produce more reliable phenotypes with less stochastic noise than the individual gene expression levels, which increases our power to discover biologically relevant associations. These phenotypes could also be applied to discover associations with other environmental factors. Copyright © 2015 Brown et al.

  17. Pathway-Based Factor Analysis of Gene Expression Data Produces Highly Heritable Phenotypes That Associate with Age

    PubMed Central

    Anand Brown, Andrew; Ding, Zhihao; Viñuela, Ana; Glass, Dan; Parts, Leopold; Spector, Tim; Winn, John; Durbin, Richard

    2015-01-01

    Statistical factor analysis methods have previously been used to remove noise components from high-dimensional data prior to genetic association mapping and, in a guided fashion, to summarize biologically relevant sources of variation. Here, we show how the derived factors summarizing pathway expression can be used to analyze the relationships between expression, heritability, and aging. We used skin gene expression data from 647 twins from the MuTHER Consortium and applied factor analysis to concisely summarize patterns of gene expression to remove broad confounding influences and to produce concise pathway-level phenotypes. We derived 930 “pathway phenotypes” that summarized patterns of variation across 186 KEGG pathways (five phenotypes per pathway). We identified 69 significant associations of age with phenotype from 57 distinct KEGG pathways at a stringent Bonferroni threshold (P<5.38×10−5). These phenotypes are more heritable (h2=0.32) than gene expression levels. On average, expression levels of 16% of genes within these pathways are associated with age. Several significant pathways relate to metabolizing sugars and fatty acids; others relate to insulin signaling. We have demonstrated that factor analysis methods combined with biological knowledge can produce more reliable phenotypes with less stochastic noise than the individual gene expression levels, which increases our power to discover biologically relevant associations. These phenotypes could also be applied to discover associations with other environmental factors. PMID:25758824

  18. Common cause evaluations in applied risk analysis of nuclear power plants. [PWR

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

    Taniguchi, T.; Ligon, D.; Stamatelatos, M.

    1983-04-01

    Qualitative and quantitative approaches were developed for the evaluation of common cause failures (CCFs) in nuclear power plants and were applied to the analysis of the auxiliary feedwater systems of several pressurized water reactors (PWRs). Key CCF variables were identified through a survey of experts in the field and a review of failure experience in operating PWRs. These variables were classified into categories of high, medium, and low defense against a CCF. Based on the results, a checklist was developed for analyzing CCFs of systems. Several known techniques for quantifying CCFs were also reviewed. The information provided valuable insights inmore » the development of a new model for estimating CCF probabilities, which is an extension of and improvement over the Beta Factor method. As applied to the analysis of the PWR auxiliary feedwater systems, the method yielded much more realistic values than the original Beta Factor method for a one-out-of-three system.« less

  19. The Design and Analysis of Transposon-Insertion Sequencing Experiments

    PubMed Central

    Chao, Michael C.; Abel, Sören; Davis, Brigid M.; Waldor, Matthew K.

    2016-01-01

    Preface Transposon-insertion sequencing (TIS) is a powerful approach that can be widely applied to genome-wide definition of loci that are required for growth in diverse conditions. However, experimental design choices and stochastic biological processes can heavily influence the results of TIS experiments and affect downstream statistical analysis. Here, we discuss TIS experimental parameters and how these factors relate to the benefits and limitations of the various statistical frameworks that can be applied to computational analysis of TIS data. PMID:26775926

  20. Source apportionment of groundwater pollution around landfill site in Nagpur, India.

    PubMed

    Pujari, Paras R; Deshpande, Vijaya

    2005-12-01

    The present work attempts statistical analysis of groundwater quality near a Landfill site in Nagpur, India. The objective of the present work is to figure out the impact of different factors on the quality of groundwater in the study area. Statistical analysis of the data has been attempted by applying Factor Analysis concept. The analysis brings out the effect of five different factors governing the groundwater quality in the study area. Based on the contribution of the different parameters present in the extracted factors, the latter are linked to the geological setting, the leaching from the host rock, leachate of heavy metals from the landfill as well as the bacterial contamination from landfill site and other anthropogenic activities. The analysis brings out the vulnerability of the unconfined aquifer to contamination.

  1. Confirmatory Factor Analytic Structure and Measurement Invariance of Quantitative Autistic Traits Measured by the Social Responsiveness Scale-2

    ERIC Educational Resources Information Center

    Frazier, Thomas W.; Ratliff, Kristin R.; Gruber, Chris; Zhang, Yi; Law, Paul A.; Constantino, John N.

    2014-01-01

    Understanding the factor structure of autistic symptomatology is critical to the discovery and interpretation of causal mechanisms in autism spectrum disorder. We applied confirmatory factor analysis and assessment of measurement invariance to a large ("N" = 9635) accumulated collection of reports on quantitative autistic traits using…

  2. Measurement Invariance of Big-Five Factors over the Life Span: ESEM Tests of Gender, Age, Plasticity, Maturity, and La Dolce Vita Effects

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Nagengast, Benjamin; Morin, Alexandre J. S.

    2013-01-01

    This substantive-methodological synergy applies evolving approaches to factor analysis to substantively important developmental issues of how five-factor-approach (FFA) personality measures vary with gender, age, and their interaction. Confirmatory factor analyses (CFAs) conducted at the item level often do not support a priori FFA structures, due…

  3. Pharmaceutical strategic purchasing requirements in Iran: Price interventions and the related effective factors

    PubMed Central

    Bastani, Peivand; Dinarvand, Rasoul; SamadBeik, Mahnaz; Pourmohammadi, Kimia

    2016-01-01

    Objective: Pharmaceutical access for the poor is an essential factor in developing countries that can be improved through strategic purchasing. This study was conducted to identify the elements affecting price in order to enable insurance organizations to put strategic purchasing into practice. Methods: This was a qualitative study conducted through content analysis with an inductive approach applying a five-stage framework analysis (familiarization, identifying a thematic framework, indexing, mapping, and interpretation). Data analysis was started right after transcribing each interview applying ATLAS.ti. Data were saturated after 32 semi-structured interviews by experts. These key informants were selected purposefully and through snowball sampling. Findings: Findings showed that there are four main themes as Pharmaceutical Strategic Purchasing Requirements in Iran as follows essential and structural factors, international factors, economical factors, and legal factors. Moreover, totally 14 related sub-themes were extracted in this area as the main effective variables. Conclusion: It seems that paying adequate attention to the four present themes and 14 sub-themes affecting price can enable health system policy-makers of developing countries like Iran to make the best decisions through strategic purchasing of drugs by the main insurers in order to improve access and health in the country. PMID:26985434

  4. The development of the Problematic Online Gaming Questionnaire (POGQ).

    PubMed

    Demetrovics, Zsolt; Urbán, Róbert; Nagygyörgy, Katalin; Farkas, Judit; Griffiths, Mark D; Pápay, Orsolya; Kökönyei, Gyöngyi; Felvinczi, Katalin; Oláh, Attila

    2012-01-01

    Online gaming has become increasingly popular. However, this has led to concerns that these games might induce serious problems and/or lead to dependence for a minority of players. The aim of this study was to uncover and operationalize the components of problematic online gaming. A total of 3415 gamers (90% males; mean age 21 years), were recruited through online gaming websites. A combined method of exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) was applied. Latent profile analysis was applied to identify persons at-risk. EFA revealed a six-factor structure in the background of problematic online gaming that was also confirmed by a CFA. For the assessment of the identified six dimensions--preoccupation, overuse, immersion, social isolation, interpersonal conflicts, and withdrawal--the 18-item Problematic Online Gaming Questionnaire (POGQ) proved to be exceedingly suitable. Based on the latent profile analysis, 3.4% of the gamer population was considered to be at high risk, while another 15.2% was moderately problematic. The POGQ seems to be an adequate measurement tool for the differentiated assessment of gaming related problems on six subscales.

  5. Developmental and Individual Differences in Chinese Writing

    PubMed Central

    Guan, Connie Qun; Ye, Feifei; Wagner, Richard K.; Meng, Wanjin

    2015-01-01

    The goal of the present study was to examine the generalizability of a model of the underlying dimensions of written composition across writing systems (Chinese Mandarin vs. English) and level of writing skill. A five-factor model of writing originally developed from analyses of 1st and 4th grade English writing samples was applied to Chinese writing samples obtained from 4th and 7th grade students. Confirmatory factor analysis was used to compare the fits of alternative models of written composition. The results suggest that the five-factor model of written composition generalizes to Chinese writing samples and applies to both less skilled (Grade 4) and more skilled (Grade 7) writing, with differences in factor means between grades that vary in magnitude across factors. PMID:26038631

  6. Electromagnetic Compatibility (EMC) in Microelectronics.

    DTIC Science & Technology

    1983-02-01

    Fault Tree Analysis", System Saftey Symposium, June 8-9, 1965, Seattle: The Boeing Company . 12. Fussell, J.B., "Fault Tree Analysis-Concepts and...procedure for assessing EMC in microelectronics and for applying DD, 1473 EOiTO OP I, NOV6 IS OESOL.ETE UNCLASSIFIED SECURITY CLASSIFICATION OF THIS...CRITERIA 2.1 Background 2 2.2 The Probabilistic Nature of EMC 2 2.3 The Probabilistic Approach 5 2.4 The Compatibility Factor 6 3 APPLYING PROBABILISTIC

  7. The Rewards of Human Capital Competences for Young European Higher Education Graduates

    ERIC Educational Resources Information Center

    Garcia-Aracil, Adela; Mora, Jose-Gines; Vila, Luis E.

    2004-01-01

    The labour market rewards for a number of required human capital competences are analysed using a sample of young European higher education graduates. Factor analysis is applied to classify competences by jobs into eight orthogonal groups, namely participative, methodological, specialised, organisational, applying rules, physical, generic and…

  8. Psychosocial risk and protective factors for depression in the dialysis population: a systematic review and meta-regression analysis.

    PubMed

    Chan, Ramony; Steel, Zachary; Brooks, Robert; Heung, Tracy; Erlich, Jonathan; Chow, Josephine; Suranyi, Michael

    2011-11-01

    Research into the association between psychosocial factors and depression in End-Stage Renal Disease (ESRD) has expanded considerably in recent years identifying a range of factors that may act as important risk and protective factors of depression for this population. The present study provides the first systematic review and meta-analysis of this body of research. Published studies reporting associations between any psychosocial factor and depression were identified and retrieved from Medline, Embase, and PsycINFO, by applying optimised search strategies. Mean effect sizes were calculated for the associations across five psychosocial constructs (social support, personality attributes, cognitive appraisal, coping process, stress/stressor). Multiple hierarchical meta-regression analysis was applied to examine the moderating effects of methodological and substantive factors on the strength of the observed associations. 57 studies covering 58 independent samples with 5956 participants were identified, resulting in 246 effect sizes of the association between a range of psychosocial factors and depression. The overall mean effect size (Pearsons correlation coefficient) of the association between psychosocial factor and depression was 0.36. The effect sizes between the five psychosocial constructs and depression ranged from medium (0.27) to large levels (0.46) with personality attributes (0.46) and cognitive appraisal (0.46) having the largest effect sizes. In the meta-regression analyses, identified demographic (gender, age, location of study) and treatment (type of dialysis) characteristics moderated the strength of the associations with depression. The current analysis documents a moderate to large association between the presence of psychosocial risk factors and depression in ESRD. 2011. Published by Elsevier Inc. All rights reserved.

  9. Micropollutants throughout an integrated urban drainage model: Sensitivity and uncertainty analysis

    NASA Astrophysics Data System (ADS)

    Mannina, Giorgio; Cosenza, Alida; Viviani, Gaspare

    2017-11-01

    The paper presents the sensitivity and uncertainty analysis of an integrated urban drainage model which includes micropollutants. Specifically, a bespoke integrated model developed in previous studies has been modified in order to include the micropollutant assessment (namely, sulfamethoxazole - SMX). The model takes into account also the interactions between the three components of the system: sewer system (SS), wastewater treatment plant (WWTP) and receiving water body (RWB). The analysis has been applied to an experimental catchment nearby Palermo (Italy): the Nocella catchment. Overall, five scenarios, each characterized by different uncertainty combinations of sub-systems (i.e., SS, WWTP and RWB), have been considered applying, for the sensitivity analysis, the Extended-FAST method in order to select the key factors affecting the RWB quality and to design a reliable/useful experimental campaign. Results have demonstrated that sensitivity analysis is a powerful tool for increasing operator confidence in the modelling results. The approach adopted here can be used for blocking some non-identifiable factors, thus wisely modifying the structure of the model and reducing the related uncertainty. The model factors related to the SS have been found to be the most relevant factors affecting the SMX modeling in the RWB when all model factors (scenario 1) or model factors of SS (scenarios 2 and 3) are varied. If the only factors related to the WWTP are changed (scenarios 4 and 5), the SMX concentration in the RWB is mainly influenced (till to 95% influence of the total variance for SSMX,max) by the aerobic sorption coefficient. A progressive uncertainty reduction from the upstream to downstream was found for the soluble fraction of SMX in the RWB.

  10. Evaluating WAIS-IV structure through a different psychometric lens: structural causal model discovery as an alternative to confirmatory factor analysis.

    PubMed

    van Dijk, Marjolein J A M; Claassen, Tom; Suwartono, Christiany; van der Veld, William M; van der Heijden, Paul T; Hendriks, Marc P H

    Since the publication of the WAIS-IV in the U.S. in 2008, efforts have been made to explore the structural validity by applying factor analysis to various samples. This study aims to achieve a more fine-grained understanding of the structure of the Dutch language version of the WAIS-IV (WAIS-IV-NL) by applying an alternative analysis based on causal modeling in addition to confirmatory factor analysis (CFA). The Bayesian Constraint-based Causal Discovery (BCCD) algorithm learns underlying network structures directly from data and assesses more complex structures than is possible with factor analysis. WAIS-IV-NL profiles of two clinical samples of 202 patients (i.e. patients with temporal lobe epilepsy and a mixed psychiatric outpatient group) were analyzed and contrasted with a matched control group (N = 202) selected from the Dutch standardization sample of the WAIS-IV-NL to investigate internal structure by means of CFA and BCCD. With CFA, the four-factor structure as proposed by Wechsler demonstrates acceptable fit in all three subsamples. However, BCCD revealed three consistent clusters (verbal comprehension, visual processing, and processing speed) in all three subsamples. The combination of Arithmetic and Digit Span as a coherent working memory factor could not be verified, and Matrix Reasoning appeared to be isolated. With BCCD, some discrepancies from the proposed four-factor structure are exemplified. Furthermore, these results fit CHC theory of intelligence more clearly. Consistent clustering patterns indicate these results are robust. The structural causal discovery approach may be helpful in better interpreting existing tests, the development of new tests, and aid in diagnostic instruments.

  11. The Licensing of Behavior Analysts: Protecting the Profession and the Public

    ERIC Educational Resources Information Center

    Hassert, Derrick L.; Kelly, Amanda N.; Pritchard, Joshua K.; Cautilli, Joseph D.

    2008-01-01

    Applied behavior analysis is a hybrid tradition with roots in many mental health disciplines. Even with these diverse origins, the professional practice of behavior analysis remains distinct and identifiable. Given these factors the professional practice special interest group (SIG) for the Association for Behavior Analysis International has…

  12. Do review articles boost journal impact factors? A longitudinal analysis for five pharmacology journals.

    PubMed

    Amiri, Marjan; Michel, Martin C

    2018-06-21

    The impact factor is a frequently applied tool in research output analytics. Based on five consecutive publication years each of five pharmacology journals, we have analyzed to which extent review articles yield more impact factor-relevant citations than original articles. Our analysis shows that review articles are quoted about twice as often as original articles published in the same year in the same journal. We conclude that inclusion of review articles does not substantially affect the impact factor of a journal unless they account for considerably more than 10% of all published articles.

  13. The effects of common risk factors on stock returns: A detrended cross-correlation analysis

    NASA Astrophysics Data System (ADS)

    Ruan, Qingsong; Yang, Bingchan

    2017-10-01

    In this paper, we investigate the cross-correlations between Fama and French three factors and the return of American industries on the basis of cross-correlation statistic test and multifractal detrended cross-correlation analysis (MF-DCCA). Qualitatively, we find that the return series of Fama and French three factors and American industries were overall significantly cross-correlated based on the analysis of a statistic. Quantitatively, we find that the cross-correlations between three factors and the return of American industries were strongly multifractal, and applying MF-DCCA we also investigate the cross-correlation of industry returns and residuals. We find that there exists multifractality of industry returns and residuals. The result of correlation coefficients we can verify that there exist other factors which influence the industry returns except Fama three factors.

  14. Using Module Analysis for Multiple Choice Responses: A New Method Applied to Force Concept Inventory Data

    ERIC Educational Resources Information Center

    Brewe, Eric; Bruun, Jesper; Bearden, Ian G.

    2016-01-01

    We describe "Module Analysis for Multiple Choice Responses" (MAMCR), a new methodology for carrying out network analysis on responses to multiple choice assessments. This method is used to identify modules of non-normative responses which can then be interpreted as an alternative to factor analysis. MAMCR allows us to identify conceptual…

  15. ADAPTION OF NONSTANDARD PIPING COMPONENTS INTO PRESENT DAY SEISMIC CODES

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

    D. T. Clark; M. J. Russell; R. E. Spears

    2009-07-01

    With spiraling energy demand and flat energy supply, there is a need to extend the life of older nuclear reactors. This sometimes requires that existing systems be evaluated to present day seismic codes. Older reactors built in the 1960s and early 1970s often used fabricated piping components that were code compliant during their initial construction time period, but are outside the standard parameters of present-day piping codes. There are several approaches available to the analyst in evaluating these non-standard components to modern codes. The simplest approach is to use the flexibility factors and stress indices for similar standard components withmore » the assumption that the non-standard component’s flexibility factors and stress indices will be very similar. This approach can require significant engineering judgment. A more rational approach available in Section III of the ASME Boiler and Pressure Vessel Code, which is the subject of this paper, involves calculation of flexibility factors using finite element analysis of the non-standard component. Such analysis allows modeling of geometric and material nonlinearities. Flexibility factors based on these analyses are sensitive to the load magnitudes used in their calculation, load magnitudes that need to be consistent with those produced by the linear system analyses where the flexibility factors are applied. This can lead to iteration, since the magnitude of the loads produced by the linear system analysis depend on the magnitude of the flexibility factors. After the loading applied to the nonstandard component finite element model has been matched to loads produced by the associated linear system model, the component finite element model can then be used to evaluate the performance of the component under the loads with the nonlinear analysis provisions of the Code, should the load levels lead to calculated stresses in excess of Allowable stresses. This paper details the application of component-level finite element modeling to account for geometric and material nonlinear component behavior in a linear elastic piping system model. Note that this technique can be applied to the analysis of B31 piping systems.« less

  16. Orthogonal Higher Order Structure and Confirmatory Factor Analysis of the French Wechsler Adult Intelligence Scale (WAIS-III)

    ERIC Educational Resources Information Center

    Golay, Philippe; Lecerf, Thierry

    2011-01-01

    According to the most widely accepted Cattell-Horn-Carroll (CHC) model of intelligence measurement, each subtest score of the Wechsler Intelligence Scale for Adults (3rd ed.; WAIS-III) should reflect both 1st- and 2nd-order factors (i.e., 4 or 5 broad abilities and 1 general factor). To disentangle the contribution of each factor, we applied a…

  17. The effect of choosing three different C factor formulae derived from NDVI on a fully raster-based erosion modelling

    NASA Astrophysics Data System (ADS)

    Sulistyo, Bambang

    2016-11-01

    The research was aimed at studying the efect of choosing three different C factor formulae derived from NDVI on a fully raster-based erosion modelling of The USLE using remote sensing data and GIS technique. Methods applied was by analysing all factors affecting erosion such that all data were in the form of raster. Those data were R, K, LS, C and P factors. Monthly R factor was evaluated based on formula developed by Abdurachman. K factor was determined using modified formula used by Ministry of Forestry based on soil samples taken in the field. LS factor was derived from Digital Elevation Model. Three C factors used were all derived from NDVI and developed by Suriyaprasit (non-linear) and by Sulistyo (linear and non-linear). P factor was derived from the combination between slope data and landcover classification interpreted from Landsat 7 ETM+. Another analysis was the creation of map of Bulk Density used to convert erosion unit. To know the model accuracy, model validation was done by applying statistical analysis and by comparing Emodel with Eactual. A threshold value of ≥ 0.80 or ≥ 80% was chosen to justify. The research result showed that all Emodel using three formulae of C factors have coeeficient of correlation value of > 0.8. The results of analysis of variance showed that there was significantly difference between Emodel and Eactual when using C factor formula developed by Suriyaprasit and Sulistyo (non-linear). Among the three formulae, only Emodel using C factor formula developed by Sulistyo (linear) reached the accuracy of 81.13% while the other only 56.02% as developed by Sulistyo (nonlinear) and 4.70% as developed by Suriyaprasit, respectively.

  18. Quantifying Associations between Environmental Stressors and Demographic Factors

    EPA Science Inventory

    Association rule mining (ARM) [1-3], also known as frequent item set mining [4] or market basket analysis [1], has been widely applied in many different areas, such as business product portfolio planning [5], intrusion detection infrastructure design [6], gene expression analysis...

  19. Risk Factors of Falls in Community-Dwelling Older Adults: Logistic Regression Tree Analysis

    ERIC Educational Resources Information Center

    Yamashita, Takashi; Noe, Douglas A.; Bailer, A. John

    2012-01-01

    Purpose of the Study: A novel logistic regression tree-based method was applied to identify fall risk factors and possible interaction effects of those risk factors. Design and Methods: A nationally representative sample of American older adults aged 65 years and older (N = 9,592) in the Health and Retirement Study 2004 and 2006 modules was used.…

  20. Global analysis of bacterial transcription factors to predict cellular target processes.

    PubMed

    Doerks, Tobias; Andrade, Miguel A; Lathe, Warren; von Mering, Christian; Bork, Peer

    2004-03-01

    Whole-genome sequences are now available for >100 bacterial species, giving unprecedented power to comparative genomics approaches. We have applied genome-context methods to predict target processes that are regulated by transcription factors (TFs). Of 128 orthologous groups of proteins annotated as TFs, to date, 36 are functionally uncharacterized; in our analysis we predict a probable cellular target process or biochemical pathway for half of these functionally uncharacterized TFs.

  1. Clusters of Occupations Based on Systematically Derived Work Dimensions: An Exploratory Study.

    ERIC Educational Resources Information Center

    Cunningham, J. W.; And Others

    The study explored the feasibility of deriving an educationally relevant occupational cluster structure based on Occupational Analysis Inventory (OAI) work dimensions. A hierarchical cluster analysis was applied to the factor score profiles of 814 occupations on 22 higher-order OAI work dimensions. From that analysis, 73 occupational clusters were…

  2. A comprehensive study on the influence of strength and stiffness eccentricities to the on-plan rotation of asymmetric structure

    NASA Astrophysics Data System (ADS)

    Rashidi, Azida; Majid, Taksiah A.; Fadzli, M. N.; Faisal, Ade; Noor, Suhaila M.

    2017-10-01

    All buildings are subjected to some degree of torsion which in turn changes the member torsional demands from that of translation only. Torsional effects on buildings subjected to earthquakes are not found directly in structural analysis unless full three-dimensional inelastic dynamic time history analysis is conducted. Since design is often conducted using two-dimensional analysis, these effects are not directly considered. There is currently an understanding on how different factors may influence torsion, however, the degree to which these factors influence torsion is relatively unknown. Slab rotation effect is considered a major response parameter to represent the severity of the torsional response of eccentric systems; hence, it is considered in this study. The centre of strength (CR) and centre of stiffness (CS) are the two main factors under considerations. A comprehensive analysis on eighty different CR and CS conditions are applied to a three-dimensional, asymmetric building and their influences to slab rotation are observed. The CR/CS conditions are applied by varying strength eccentricities (er) and stiffness eccentricities (es) using two condition models. Then, earthquake ground motions are applied in z-direction under elastic and inelastic conditions. The results interpreted using a simple approach shows important slab rotation behaviour that forms interesting findings from this study. The slab rotation demand is found to reduce as strength eccentricity moves away from the Centre of Mass (CoM) but is independent of the stiffness eccentricity. The study also confirms finding of previous works which states that stiffness eccentricity plays a minor role when assessing the torsional behaviour of a ductile systems. Results from inelastic analysis shows slab rotation demand increases as strength eccentricity is closer to the CoM but it remains constant for elastic analysis.

  3. Using Formative Scenario Analysis approach for landslide risk analysis in a relatively scarce data environment: preliminary results

    NASA Astrophysics Data System (ADS)

    Zumpano, Veronica; Balteanu, Dan; Mazzorana, Bruno; Micu, Mihai

    2014-05-01

    It is increasingly important to provide to stakeholders tools that will enable them to better understand what is the state of the environment in which they live and manage and to help them to make decisions that aim to minimize the consequences of hydro-meteorological hazards. Very often, however, quantitative studies, especially for large areas, are difficult to perform. This is due to the fact that unfortunately isn't often possible to have the numerous data required to perform the analysis. In addition it has been proven that in scenario analysis, often deterministic approaches are not able to detect some features of the system revealing unexpected behaviors, and resulting in underestimation or omission of some impact factors. Here are presented some preliminary results obtained applying Formative Scenario Analysis that can be considered a possible solution for landslide risk analysis in cases where the data needed even if existent are not available. This method is an expert based approach that integrates intuitions and qualitative evaluations of impact factors with the quantitative analysis of relations between these factors: a group of experts with different but pertinent expertise, determine (by a rating procedure) quantitative relations between these factors, then through mathematical operations the scenarios describing a certain state of the system are obtained. The approach is applied to Buzau County (Romania), an area belonging to the Curvature Romanian Carpathians and Subcarpathians, a region strongly affected by environmental hazards. The region has been previously involved in numerous episodes of severe hydro-meteorological events that caused considerable damages (1975, 2005, 2006). In this application we are referring only to one type of landslides that can be described as shallow and medium-seated with a (mainly) translational movement that can go from slide to flow. The material involved can be either soil, debris or a mixture of both, in Romanian literature these typical movements has been described as alunecare curgatoare. The Formative Scenario Analysis approach will be applied for each component of risk (H,V,and A) and then the acquired states will be combined in order to obtain for obtaining a series of alternatives scenarios for risk. The approach is structured in two main sections corresponding to a level of influence of conditioning factors and a response. In this latter are obtained the results of the formative scenario approach trained with the conditioning factors of the first level. These factors are divided in two subsets representing 2 levels of influences, k=1 comprises the global factors while in k=2 one finds local factors. In order to include uncertainty estimation within the analysis the method of knowledge representation type-1 fuzzy sets is introduced and hence decisions made by experts on certain events are expressed in terms of triangular fuzzy numbers.

  4. Olympic Education as a Factor of Socialization of Preschoolers

    ERIC Educational Resources Information Center

    Varfolomeeva, Zoya S.; Surinov, Ilya A.

    2016-01-01

    The purpose of this study is theoretical substantiation and experimental confirmation of importance of the Olympic education as a socialization factor of the preschoolers. To address the study issues, theoretical methods of analysis, generalization and systematization as well as personal and activity approaches were applied. The older preschoolers…

  5. Incompressible boundary-layer stability analysis of LFC experimental data for sub-critical Mach numbers. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Berry, S. A.

    1986-01-01

    An incompressible boundary-layer stability analysis of Laminar Flow Control (LFC) experimental data was completed and the results are presented. This analysis was undertaken for three reasons: to study laminar boundary-layer stability on a modern swept LFC airfoil; to calculate incompressible design limits of linear stability theory as applied to a modern airfoil at high subsonic speeds; and to verify the use of linear stability theory as a design tool. The experimental data were taken from the slotted LFC experiment recently completed in the NASA Langley 8-Foot Transonic Pressure Tunnel. Linear stability theory was applied and the results were compared with transition data to arrive at correlated n-factors. Results of the analysis showed that for the configuration and cases studied, Tollmien-Schlichting (TS) amplification was the dominating disturbance influencing transition. For these cases, incompressible linear stability theory correlated with an n-factor for TS waves of approximately 10 at transition. The n-factor method correlated rather consistently to this value despite a number of non-ideal conditions which indicates the method is useful as a design tool for advanced laminar flow airfoils.

  6. The Development of the Problematic Online Gaming Questionnaire (POGQ)

    PubMed Central

    Demetrovics, Zsolt; Urbán, Róbert; Nagygyörgy, Katalin; Farkas, Judit; Griffiths, Mark D.; Pápay, Orsolya; Kökönyei, Gyöngyi; Felvinczi, Katalin; Oláh, Attila

    2012-01-01

    Background Online gaming has become increasingly popular. However, this has led to concerns that these games might induce serious problems and/or lead to dependence for a minority of players. Aim: The aim of this study was to uncover and operationalize the components of problematic online gaming. Methods A total of 3415 gamers (90% males; mean age 21 years), were recruited through online gaming websites. A combined method of exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) was applied. Latent profile analysis was applied to identify persons at-risk. Results EFA revealed a six-factor structure in the background of problematic online gaming that was also confirmed by a CFA. For the assessment of the identified six dimensions – preoccupation, overuse, immersion, social isolation, interpersonal conflicts, and withdrawal – the 18-item Problematic Online Gaming Questionnaire (POGQ) proved to be exceedingly suitable. Based on the latent profile analysis, 3.4% of the gamer population was considered to be at high risk, while another 15.2% was moderately problematic. Conclusions The POGQ seems to be an adequate measurement tool for the differentiated assessment of gaming related problems on six subscales. PMID:22590541

  7. A refined method for multivariate meta-analysis and meta-regression.

    PubMed

    Jackson, Daniel; Riley, Richard D

    2014-02-20

    Making inferences about the average treatment effect using the random effects model for meta-analysis is problematic in the common situation where there is a small number of studies. This is because estimates of the between-study variance are not precise enough to accurately apply the conventional methods for testing and deriving a confidence interval for the average effect. We have found that a refined method for univariate meta-analysis, which applies a scaling factor to the estimated effects' standard error, provides more accurate inference. We explain how to extend this method to the multivariate scenario and show that our proposal for refined multivariate meta-analysis and meta-regression can provide more accurate inferences than the more conventional approach. We explain how our proposed approach can be implemented using standard output from multivariate meta-analysis software packages and apply our methodology to two real examples. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Evaluation of standardized and applied variables in predicting treatment outcomes of polytrauma patients.

    PubMed

    Aksamija, Goran; Mulabdic, Adi; Rasic, Ismar; Muhovic, Samir; Gavric, Igor

    2011-01-01

    Polytrauma is defined as an injury where they are affected by at least two different organ systems or body, with at least one life-threatening injuries. Given the multilevel model care of polytrauma patients within KCUS are inevitable weaknesses in the management of this category of patients. To determine the dynamics of existing procedures in treatment of polytrauma patients on admission to KCUS, and based on statistical analysis of variables applied to determine and define the factors that influence the final outcome of treatment, and determine their mutual relationship, which may result in eliminating the flaws in the approach to the problem. The study was based on 263 polytrauma patients. Parametric and non-parametric statistical methods were used. Basic statistics were calculated, based on the calculated parameters for the final achievement of research objectives, multicoleration analysis, image analysis, discriminant analysis and multifactorial analysis were used. From the universe of variables for this study we selected sample of n = 25 variables, of which the first two modular, others belong to the common measurement space (n = 23) and in this paper defined as a system variable methods, procedures and assessments of polytrauma patients. After the multicoleration analysis, since the image analysis gave a reliable measurement results, we started the analysis of eigenvalues, that is defining the factors upon which they obtain information about the system solve the problem of the existing model and its correlation with treatment outcome. The study singled out the essential factors that determine the current organizational model of care, which may affect the treatment and better outcome of polytrauma patients. This analysis has shown the maximum correlative relationships between these practices and contributed to development guidelines that are defined by isolated factors.

  9. Success Factors of European Syndromic Surveillance Systems: A Worked Example of Applying Qualitative Comparative Analysis

    PubMed Central

    Ziemann, Alexandra; Fouillet, Anne; Brand, Helmut; Krafft, Thomas

    2016-01-01

    Introduction Syndromic surveillance aims at augmenting traditional public health surveillance with timely information. To gain a head start, it mainly analyses existing data such as from web searches or patient records. Despite the setup of many syndromic surveillance systems, there is still much doubt about the benefit of the approach. There are diverse interactions between performance indicators such as timeliness and various system characteristics. This makes the performance assessment of syndromic surveillance systems a complex endeavour. We assessed if the comparison of several syndromic surveillance systems through Qualitative Comparative Analysis helps to evaluate performance and identify key success factors. Materials and Methods We compiled case-based, mixed data on performance and characteristics of 19 syndromic surveillance systems in Europe from scientific and grey literature and from site visits. We identified success factors by applying crisp-set Qualitative Comparative Analysis. We focused on two main areas of syndromic surveillance application: seasonal influenza surveillance and situational awareness during different types of potentially health threatening events. Results We found that syndromic surveillance systems might detect the onset or peak of seasonal influenza earlier if they analyse non-clinical data sources. Timely situational awareness during different types of events is supported by an automated syndromic surveillance system capable of analysing multiple syndromes. To our surprise, the analysis of multiple data sources was no key success factor for situational awareness. Conclusions We suggest to consider these key success factors when designing or further developing syndromic surveillance systems. Qualitative Comparative Analysis helped interpreting complex, mixed data on small-N cases and resulted in concrete and practically relevant findings. PMID:27182731

  10. Success Factors of European Syndromic Surveillance Systems: A Worked Example of Applying Qualitative Comparative Analysis.

    PubMed

    Ziemann, Alexandra; Fouillet, Anne; Brand, Helmut; Krafft, Thomas

    2016-01-01

    Syndromic surveillance aims at augmenting traditional public health surveillance with timely information. To gain a head start, it mainly analyses existing data such as from web searches or patient records. Despite the setup of many syndromic surveillance systems, there is still much doubt about the benefit of the approach. There are diverse interactions between performance indicators such as timeliness and various system characteristics. This makes the performance assessment of syndromic surveillance systems a complex endeavour. We assessed if the comparison of several syndromic surveillance systems through Qualitative Comparative Analysis helps to evaluate performance and identify key success factors. We compiled case-based, mixed data on performance and characteristics of 19 syndromic surveillance systems in Europe from scientific and grey literature and from site visits. We identified success factors by applying crisp-set Qualitative Comparative Analysis. We focused on two main areas of syndromic surveillance application: seasonal influenza surveillance and situational awareness during different types of potentially health threatening events. We found that syndromic surveillance systems might detect the onset or peak of seasonal influenza earlier if they analyse non-clinical data sources. Timely situational awareness during different types of events is supported by an automated syndromic surveillance system capable of analysing multiple syndromes. To our surprise, the analysis of multiple data sources was no key success factor for situational awareness. We suggest to consider these key success factors when designing or further developing syndromic surveillance systems. Qualitative Comparative Analysis helped interpreting complex, mixed data on small-N cases and resulted in concrete and practically relevant findings.

  11. A Correction to the Stress-Strain Curve During Multistage Hot Deformation of 7150 Aluminum Alloy Using Instantaneous Friction Factors

    NASA Astrophysics Data System (ADS)

    Jiang, Fulin; Tang, Jie; Fu, Dinfa; Huang, Jianping; Zhang, Hui

    2018-04-01

    Multistage stress-strain curve correction based on an instantaneous friction factor was studied for axisymmetric uniaxial hot compression of 7150 aluminum alloy. Experimental friction factors were calculated based on continuous isothermal axisymmetric uniaxial compression tests at various deformation parameters. Then, an instantaneous friction factor equation was fitted by mathematic analysis. After verification by comparing single-pass flow stress correction with traditional average friction factor correction, the instantaneous friction factor equation was applied to correct multistage stress-strain curves. The corrected results were reasonable and validated by multistage relative softening calculations. This research provides a broad potential for implementing axisymmetric uniaxial compression in multistage physical simulations and friction optimization in finite element analysis.

  12. Uncertainty analysis of diffuse-gray radiation enclosure problems: A hypersensitive case study

    NASA Technical Reports Server (NTRS)

    Taylor, Robert P.; Luck, Rogelio; Hodge, B. K.; Steele, W. Glenn

    1993-01-01

    An uncertainty analysis of diffuse-gray enclosure problems is presented. The genesis was a diffuse-gray enclosure problem which proved to be hypersensitive to the specification of view factors. This genesis is discussed in some detail. The uncertainty analysis is presented for the general diffuse-gray enclosure problem and applied to the hypersensitive case study. It was found that the hypersensitivity could be greatly reduced by enforcing both closure and reciprocity for the view factors. The effects of uncertainties in the surface emissivities and temperatures are also investigated.

  13. Validating the European Health Literacy Survey Questionnaire in people with type 2 diabetes: Latent trait analyses applying multidimensional Rasch modelling and confirmatory factor analysis.

    PubMed

    Finbråten, Hanne Søberg; Pettersen, Kjell Sverre; Wilde-Larsson, Bodil; Nordström, Gun; Trollvik, Anne; Guttersrud, Øystein

    2017-11-01

    To validate the European Health Literacy Survey Questionnaire (HLS-EU-Q47) in people with type 2 diabetes mellitus. The HLS-EU-Q47 latent variable is outlined in a framework with four cognitive domains integrated in three health domains, implying 12 theoretically defined subscales. Valid and reliable health literacy measurers are crucial to effectively adapt health communication and education to individuals and groups of patients. Cross-sectional study applying confirmatory latent trait analyses. Using a paper-and-pencil self-administered approach, 388 adults responded in March 2015. The data were analysed using the Rasch methodology and confirmatory factor analysis. Response violation (response dependency) and trait violation (multidimensionality) of local independence were identified. Fitting the "multidimensional random coefficients multinomial logit" model, 1-, 3- and 12-dimensional Rasch models were applied and compared. Poor model fit and differential item functioning were present in some items, and several subscales suffered from poor targeting and low reliability. Despite multidimensional data, we did not observe any unordered response categories. Interpreting the domains as distinct but related latent dimensions, the data fit a 12-dimensional Rasch model and a 12-factor confirmatory factor model best. Therefore, the analyses did not support the estimation of one overall "health literacy score." To support the plausibility of claims based on the HLS-EU score(s), we suggest: removing the health care aspect to reduce the magnitude of multidimensionality; rejecting redundant items to avoid response dependency; adding "harder" items and applying a six-point rating scale to improve subscale targeting and reliability; and revising items to improve model fit and avoid bias owing to person factors. © 2017 John Wiley & Sons Ltd.

  14. Applying parallel factor analysis and Tucker-3 methods on sensory and instrumental data to establish preference maps: case study on sweet corn varieties.

    PubMed

    Gere, Attila; Losó, Viktor; Györey, Annamária; Kovács, Sándor; Huzsvai, László; Nábrádi, András; Kókai, Zoltán; Sipos, László

    2014-12-01

    Traditional internal and external preference mapping methods are based on principal component analysis (PCA). However, parallel factor analysis (PARAFAC) and Tucker-3 methods could be a better choice. To evaluate the methods, preference maps of sweet corn varieties will be introduced. A preference map of eight sweet corn varieties was established using PARAFAC and Tucker-3 methods. Instrumental data were also integrated into the maps. The triplot created by the PARAFAC model explains better how odour is separated from texture or appearance, and how some varieties are separated from others. Internal and external preference maps were created using parallel factor analysis (PARAFAC) and Tucker-3 models employing both sensory (trained panel and consumers) and instrumental parameters simultaneously. Triplots of the applied three-way models have a competitive advantage compared to the traditional biplots of the PCA-based external preference maps. The solution of PARAFAC and Tucker-3 is very similar regarding the interpretation of the first and third factors. The main difference is due to the second factor as it differentiated the attributes better. Consumers who prefer 'super sweet' varieties (they place great emphasis especially on taste) are much younger and have significantly higher incomes, and buy sweet corn products rarely (once a month). Consumers who consume sweet corn products mainly because of their texture and appearance are significantly older and include a higher ratio of men. © 2014 Society of Chemical Industry.

  15. Development of a short-form Learning Organization Survey: the LOS-27.

    PubMed

    Singer, Sara J; Moore, Scott C; Meterko, Mark; Williams, Sandra

    2012-08-01

    Despite urgent need for innovation, adaptation, and change in health care, few tools enable researchers or practitioners to assess the extent to which health care facilities perform as learning organizations or the effects of initiatives that require learning. This study's objective was to develop and test a short-form Learning Organization Survey to fill this gap. The authors applied exploratory factor analysis and confirmatory factor analysis to data from Veterans Health Administration personnel to derive a short-form survey and then conducted further confirmatory factor analysis and factor invariance testing on additional Veterans Health Administration data to evaluate the short form. Results suggest that a 27-item, 7-factor survey (2 environmental factors, 1 on leadership, and 4 on concrete learning processes and practices) reliably measures key features of organizational learning, allowing researchers to evaluate theoretical propositions about organizational learning, its antecedents, and outcomes and enabling managers to assess and enhance organizations' learning capabilities and performance.

  16. Differential distribution of amino acids in plants.

    PubMed

    Kumar, Vinod; Sharma, Anket; Kaur, Ravdeep; Thukral, Ashwani Kumar; Bhardwaj, Renu; Ahmad, Parvaiz

    2017-05-01

    Plants are a rich source of amino acids and their individual abundance in plants is of great significance especially in terms of food. Therefore, it is of utmost necessity to create a database of the relative amino acid contents in plants as reported in literature. Since in most of the cases complete analysis of profiles of amino acids in plants was not reported, the units used and the methods applied and the plant parts used were different, amino acid contents were converted into relative units with respect to lysine for statistical analysis. The most abundant amino acids in plants are glutamic acid and aspartic acid. Pearson's correlation analysis among different amino acids showed that there were no negative correlations between the amino acids. Cluster analysis (CA) applied to relative amino acid contents of different families. Alismataceae, Cyperaceae, Capparaceae and Cactaceae families had close proximity with each other on the basis of their relative amino acid contents. First three components of principal component analysis (PCA) explained 79.5% of the total variance. Factor analysis (FA) explained four main underlying factors for amino acid analysis. Factor-1 accounted for 29.4% of the total variance and had maximum loadings on glycine, isoleucine, leucine, threonine and valine. Factor-2 explained 25.8% of the total variance and had maximum loadings on alanine, aspartic acid, serine and tyrosine. 14.2% of the total variance was explained by factor-3 and had maximum loadings on arginine and histidine. Factor-4 accounted 8.3% of the total variance and had maximum loading on the proline amino acid. The relative content of different amino acids presented in this paper is alanine (1.4), arginine (1.8), asparagine (0.7), aspartic acid (2.4), cysteine (0.5), glutamic acid (2.8), glutamine (0.6), glycine (1.0), histidine (0.5), isoleucine (0.9), leucine (1.7), lysine (1.0), methionine (0.4), phenylalanine (0.9), proline (1.1), serine (1.0), threonine (1.0), tryptophan (0.3), tyrosine (0.7) and valine (1.2).

  17. Different approaches in Partial Least Squares and Artificial Neural Network models applied for the analysis of a ternary mixture of Amlodipine, Valsartan and Hydrochlorothiazide

    NASA Astrophysics Data System (ADS)

    Darwish, Hany W.; Hassan, Said A.; Salem, Maissa Y.; El-Zeany, Badr A.

    2014-03-01

    Different chemometric models were applied for the quantitative analysis of Amlodipine (AML), Valsartan (VAL) and Hydrochlorothiazide (HCT) in ternary mixture, namely, Partial Least Squares (PLS) as traditional chemometric model and Artificial Neural Networks (ANN) as advanced model. PLS and ANN were applied with and without variable selection procedure (Genetic Algorithm GA) and data compression procedure (Principal Component Analysis PCA). The chemometric methods applied are PLS-1, GA-PLS, ANN, GA-ANN and PCA-ANN. The methods were used for the quantitative analysis of the drugs in raw materials and pharmaceutical dosage form via handling the UV spectral data. A 3-factor 5-level experimental design was established resulting in 25 mixtures containing different ratios of the drugs. Fifteen mixtures were used as a calibration set and the other ten mixtures were used as validation set to validate the prediction ability of the suggested methods. The validity of the proposed methods was assessed using the standard addition technique.

  18. Factor analysis and cluster analysis applied to assess the water quality of middle and lower Han River in Central China

    NASA Astrophysics Data System (ADS)

    Kuo, Yi-Ming; Liu, Wen-Wen

    2015-04-01

    The Han River basin is one of the most important industrial and grain production bases in the central China. A lot of factories and towns have been established along the river where large farmlands are located nearby. In the last few decades the water quality of the Han River, specifically in middle and lower reaches, has gradually declined. The agricultural nonpoint pollution and municipal and industrial point pollution significantly degrade the water quality of the Han River. Factor analysis can be applied to reduce the dimensionality of a data set consisting of a large number of inter-related variables. Cluster analysis can classify the samples according to their similar characters. In this study, factor analysis is used to identify major pollution indicators, and cluster analysis is employed to classify the samples based on the sample locations and hydrochemical variables. Water samples were collected from 12 sample sites collected from Xiangyang City (middle Han River) to Wuhan City (lower Han River). Correlations among 25 hydrochemical variables are statistically examined. The important pollutants are determined by factor analysis. A three-factor model is determined and explains over 85% of the total river water quality variation. Factor 1, including SS, Chl-a, TN and TP, can be considered as the nonpoint source pollution. Factor 2, including Cl-, Br-, SO42-, Ca2+, Mg2+, K+, Fe2+ and PO43-, can be treated as the industrial pollutant pollution. Factor 3, including F- and NO3-, reflects the influence of the groundwater or self-purification capability of the river water. The various land uses along the Han River correlate well with the pollution types. In addition, the result showed that the water quality of Han River deteriorated gradually from middle to lower Han River. Some tributaries have been seriously polluted and significantly influence the mainstream water quality of the Han River. Finally, the result showed that the nonpoint pollution and the point pollution both significantly influence water quality in the middle and lower Han River. This study provides an effective method for watershed management and pollution control in Han River.

  19. Application of factor analysis of infrared spectra for quantitative determination of beta-tricalcium phosphate in calcium hydroxylapatite.

    PubMed

    Arsenyev, P A; Trezvov, V V; Saratovskaya, N V

    1997-01-01

    This work represents a method, which allows to determine phase composition of calcium hydroxylapatite basing on its infrared spectrum. The method uses factor analysis of the spectral data of calibration set of samples to determine minimal number of factors required to reproduce the spectra within experimental error. Multiple linear regression is applied to establish correlation between factor scores of calibration standards and their properties. The regression equations can be used to predict the property value of unknown sample. The regression model was built for determination of beta-tricalcium phosphate content in hydroxylapatite. Statistical estimation of quality of the model was carried out. Application of the factor analysis on spectral data allows to increase accuracy of beta-tricalcium phosphate determination and expand the range of determination towards its less concentration. Reproducibility of results is retained.

  20. Donor retention in health care in Iran: a factor analysis

    PubMed Central

    Aghababa, Sara; Nasiripour, Amir Ashkan; Maleki, Mohammadreza; Gohari, Mahmoodreza

    2017-01-01

    Background: Long-term financial support is essential for the survival of a charitable organization. Health charities need to identify the effective factors influencing donor retention. Methods: In the present study, the items of a questionnaire were derived from both literature review and semi-structured interviews related to donor retention. Using a purposive sampling, 300 academic and executive practitioners were selected. After the follow- up, a total of 243 usable questionnaires were prepared for factor analysis. The questionnaire was validated based on the face and content validity and reliability through Cronbach’s α-coefficient. Results: The results of exploratory factor analysis extracted 2 factors for retention: donor factor (variance = 33.841%; Cronbach’s α-coefficient = 90.2) and charity factor (variance = 29.038%; Cronbach’s α-coefficient = 82.8), respectively. Subsequently, confirmatory factor analysis was applied to support the overall reasonable fit. Conclusions: In this study, it was found that repeated monetary donations are supplied to the charitable organizations when both aspects of donor factor (retention factor and charity factor) for retention are taken into consideration. This model could provide a perspective for making sustainable donations and charitable giving PMID:28955663

  1. An Alternative Approach for the Analyses and Interpretation of Attachment Sort Items

    ERIC Educational Resources Information Center

    Kirkland, John; Bimler, David; Drawneek, Andrew; McKim, Margaret; Scholmerich, Axel

    2004-01-01

    Attachment Q-Sort (AQS) is a tool for quantifying observations about toddler/caregiver relationships. Previous studies have applied factor analysis to the full 90 AQS item set to explore the structure underlying them. Here we explore that structure by applying multidimensional scaling (MDS) to judgements of inter-item similarity. AQS items are…

  2. Family Engagement in Literacy Activities: Revised Factor Structure for the Familia--An Instrument Examining Family Support for Early Literacy Development

    ERIC Educational Resources Information Center

    Buhs, Eric S.; Welch, Greg; Burt, Jennifer; Knoche, Lisa

    2011-01-01

    This study evaluated a data-set drawn using "The Familia"--a measure originally developed to evaluate shared-reading activities. A newly developed set of conceptual supports and a confirmatory factor analysis (CFA) were applied to a new factor structure/model. Data were drawn from 219 young children and their families (mean age = 43…

  3. Bem Sex Role Inventory Validation in the International Mobility in Aging Study.

    PubMed

    Ahmed, Tamer; Vafaei, Afshin; Belanger, Emmanuelle; Phillips, Susan P; Zunzunegui, Maria-Victoria

    2016-09-01

    This study investigated the measurement structure of the Bem Sex Role Inventory (BSRI) with different factor analysis methods. Most previous studies on validity applied exploratory factor analysis (EFA) to examine the BSRI. We aimed to assess the psychometric properties and construct validity of the 12-item short-form BSRI in a sample administered to 1,995 older adults from wave 1 of the International Mobility in Aging Study (IMIAS). We used Cronbach's alpha to assess internal consistency reliability and confirmatory factor analysis (CFA) to assess psychometric properties. EFA revealed a three-factor model, further confirmed by CFA and compared with the original two-factor structure model. Results revealed that a two-factor solution (instrumentality-expressiveness) has satisfactory construct validity and superior fit to data compared to the three-factor solution. The two-factor solution confirms expected gender differences in older adults. The 12-item BSRI provides a brief, psychometrically sound, and reliable instrument in international samples of older adults.

  4. Feasibility of applying the Global Positioning System to locate motor vehicle crashes : final report.

    DOT National Transportation Integrated Search

    1997-01-01

    Countermeasures for motor vehicle crashes are often determined after extensive data analysis of the crash history of a roadway segment. An important factor that drives the value of this analysis is the accuracy, or precision, with which the crash is ...

  5. Identification of Genetic Loci Underlying the Phenotypic Constructs of Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Liu, Xiao-Qing; Georgiades, Stelios; Duku, Eric; Thompson, Ann; Devlin, Bernie; Cook, Edwin H.; Wijsman, Ellen M.; Paterson, Andrew D.; Szatmari, Peter

    2011-01-01

    Objective: To investigate the underlying phenotypic constructs in autism spectrum disorders (ASD) and to identify genetic loci that are linked to these empirically derived factors. Method: Exploratory factor analysis was applied to two datasets with 28 selected Autism Diagnostic Interview-Revised (ADI-R) algorithm items. The first dataset was from…

  6. Physics Metacognition Inventory Part II: Confirmatory factor analysis and Rasch analysis

    NASA Astrophysics Data System (ADS)

    Taasoobshirazi, Gita; Bailey, MarLynn; Farley, John

    2015-11-01

    The Physics Metacognition Inventory was developed to measure physics students' metacognition for problem solving. In one of our earlier studies, an exploratory factor analysis provided evidence of preliminary construct validity, revealing six components of students' metacognition when solving physics problems including knowledge of cognition, planning, monitoring, evaluation, debugging, and information management. The college students' scores on the inventory were found to be reliable and related to students' physics motivation and physics grade. However, the results of the exploratory factor analysis indicated that the questionnaire could be revised to improve its construct validity. The goal of this study was to revise the questionnaire and establish its construct validity through a confirmatory factor analysis. In addition, a Rasch analysis was applied to the data to better understand the psychometric properties of the inventory and to further evaluate the construct validity. Results indicated that the final, revised inventory is a valid, reliable, and efficient tool for assessing student metacognition for physics problem solving.

  7. Three-dimensional finite-element analysis of chevron-notched fracture specimens

    NASA Technical Reports Server (NTRS)

    Raju, I. S.; Newman, J. C., Jr.

    1984-01-01

    Stress-intensity factors and load-line displacements were calculated for chevron-notched bar and rod fracture specimens using a three-dimensional finite-element analysis. Both specimens were subjected to simulated wedge loading (either uniform applied displacement or uniform applied load). The chevron-notch sides and crack front were assumed to be straight. Crack-length-to-specimen width ratios (a/w) ranged from 0.4 to 0.7. The width-to-thickness ratio (w/B) was 1.45 or 2. The bar specimens had a height-to-width ratio of 0.435 or 0.5. Finite-element models were composed of singularity elements around the crack front and 8-noded isoparametric elements elsewhere. The models had about 11,000 degrees of freedom. Stress-intensity factors were calculated by using a nodal-force method for distribution along the crack front and by using a compliance method for average values. The stress intensity factors and load-line displacements are presented and compared with experimental solutions from the literature. The stress intensity factors and load-line displacements were about 2.5 and 5 percent lower than the reported experimental values, respectively.

  8. Confirmatory factor analysis of different versions of the Body Shape Questionnaire applied to Brazilian university students.

    PubMed

    da Silva, Wanderson Roberto; Dias, Juliana Chioda Ribeiro; Maroco, João; Campos, Juliana Alvares Duarte Bonini

    2014-09-01

    This study aimed at evaluating the validity, reliability, and factorial invariance of the complete (34-item) and shortened (8-item and 16-item) versions of the Body Shape Questionnaire (BSQ) when applied to Brazilian university students. A total of 739 female students with a mean age of 20.44 (standard deviation=2.45) years participated. Confirmatory factor analysis was conducted to verify the degree to which the one-factor structure satisfies the proposal for the BSQ's expected structure. Two items of the 34-item version were excluded because they had factor weights (λ)<40. All models had adequate convergent validity (average variance extracted=.43-.58; composite reliability=.85-.97) and internal consistency (α=.85-.97). The 8-item B version was considered the best shortened BSQ version (Akaike information criterion=84.07, Bayes information criterion=157.75, Browne-Cudeck criterion=84.46), with strong invariance for independent samples (Δχ(2)λ(7)=5.06, Δχ(2)Cov(8)=5.11, Δχ(2)Res(16)=19.30). Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Multi-scale symbolic transfer entropy analysis of EEG

    NASA Astrophysics Data System (ADS)

    Yao, Wenpo; Wang, Jun

    2017-10-01

    From both global and local perspectives, we symbolize two kinds of EEG and analyze their dynamic and asymmetrical information using multi-scale transfer entropy. Multi-scale process with scale factor from 1 to 199 and step size of 2 is applied to EEG of healthy people and epileptic patients, and then the permutation with embedding dimension of 3 and global approach are used to symbolize the sequences. The forward and reverse symbol sequences are taken as the inputs of transfer entropy. Scale factor intervals of permutation and global way are (37, 57) and (65, 85) where the two kinds of EEG have satisfied entropy distinctions. When scale factor is 67, transfer entropy of the healthy and epileptic subjects of permutation, 0.1137 and 0.1028, have biggest difference. And the corresponding values of the global symbolization is 0.0641 and 0.0601 which lies in the scale factor of 165. Research results show that permutation which takes contribution of local information has better distinction and is more effectively applied to our multi-scale transfer entropy analysis of EEG.

  10. Testing the psychometric properties of the Environmental Attitudes Inventory on undergraduate students in the Arab context: A test-retest approach.

    PubMed

    AlMenhali, Entesar Ali; Khalid, Khalizani; Iyanna, Shilpa

    2018-01-01

    The Environmental Attitudes Inventory (EAI) was developed to evaluate the multidimensional nature of environmental attitudes; however, it is based on a dataset from outside the Arab context. This study reinvestigated the construct validity of the EAI with a new dataset and confirmed the feasibility of applying it in the Arab context. One hundred and forty-eight subjects in Study 1 and 130 in Study 2 provided valid responses. An exploratory factor analysis (EFA) was used to extract a new factor structure in Study 1, and confirmatory factor analysis (CFA) was performed in Study 2. Both studies generated a seven-factor model, and the model fit was discussed for both the studies. Study 2 exhibited satisfactory model fit indices compared to Study 1. Factor loading values of a few items in Study 1 affected the reliability values and average variance extracted values, which demonstrated low discriminant validity. Based on the results of the EFA and CFA, this study showed sufficient model fit and suggested the feasibility of applying the EAI in the Arab context with a good construct validity and internal consistency.

  11. Testing the psychometric properties of the Environmental Attitudes Inventory on undergraduate students in the Arab context: A test-retest approach

    PubMed Central

    2018-01-01

    The Environmental Attitudes Inventory (EAI) was developed to evaluate the multidimensional nature of environmental attitudes; however, it is based on a dataset from outside the Arab context. This study reinvestigated the construct validity of the EAI with a new dataset and confirmed the feasibility of applying it in the Arab context. One hundred and forty-eight subjects in Study 1 and 130 in Study 2 provided valid responses. An exploratory factor analysis (EFA) was used to extract a new factor structure in Study 1, and confirmatory factor analysis (CFA) was performed in Study 2. Both studies generated a seven-factor model, and the model fit was discussed for both the studies. Study 2 exhibited satisfactory model fit indices compared to Study 1. Factor loading values of a few items in Study 1 affected the reliability values and average variance extracted values, which demonstrated low discriminant validity. Based on the results of the EFA and CFA, this study showed sufficient model fit and suggested the feasibility of applying the EAI in the Arab context with a good construct validity and internal consistency. PMID:29758021

  12. Confirmation of the three-factor model of problematic internet use on off-line adolescent and adult samples.

    PubMed

    Koronczai, Beatrix; Urbán, Róbert; Kökönyei, Gyöngyi; Paksi, Borbála; Papp, Krisztina; Kun, Bernadette; Arnold, Petra; Kállai, János; Demetrovics, Zsolt

    2011-11-01

    As the Internet became widely used, problems associated with its excessive use became increasingly apparent. Although for the assessment of these problems several models and related questionnaires have been elaborated, there has been little effort made to confirm them. The aim of the present study was to test the three-factor model of the previously created Problematic Internet Use Questionnaire (PIUQ) by data collection methods formerly not applied (off-line group and face-to-face settings), on the one hand, and by testing on different age groups (adolescent and adult representative samples), on the other hand. Data were collected from 438 high-school students (44.5 percent boys; mean age: 16.0 years; standard deviation=0.7 years) and also from 963 adults (49.9 percent males; mean age: 33.6 years; standard deviation=11.8 years). We applied confirmatory factor analysis to confirm the measurement model of problematic Internet use. The results of the analyses carried out inevitably support the original three-factor model over the possible one-factor solution. Using latent profile analysis, we identified 11 percent of adults and 18 percent of adolescent users characterized by problematic use. Based on exploratory factor analysis, we also suggest a short form of the PIUQ consisting of nine items. Both the original 18-item version of PIUQ and its short 9-item form have satisfactory reliability and validity characteristics, and thus, they are suitable for the assessment of problematic Internet use in future studies.

  13. Enhancing the Effectiveness of Significant Event Analysis: Exploring Personal Impact and Applying Systems Thinking in Primary Care

    PubMed Central

    McNaughton, Elaine; Bruce, David; Holly, Deirdre; Forrest, Eleanor; Macleod, Marion; Kennedy, Susan; Power, Ailsa; Toppin, Denis; Black, Irene; Pooley, Janet; Taylor, Audrey; Swanson, Vivien; Kelly, Moya; Ferguson, Julie; Stirling, Suzanne; Wakeling, Judy; Inglis, Angela; McKay, John; Sargeant, Joan

    2016-01-01

    Introduction: Significant event analysis (SEA) is well established in many primary care settings but can be poorly implemented. Reasons include the emotional impact on clinicians and limited knowledge of systems thinking in establishing why events happen and formulating improvements. To enhance SEA effectiveness, we developed and tested “guiding tools” based on human factors principles. Methods: Mixed-methods development of guiding tools (Personal Booklet—to help with emotional demands and apply a human factors analysis at the individual level; Desk Pad—to guide a team-based systems analysis; and a written Report Format) by a multiprofessional “expert” group and testing with Scottish primary care practitioners who submitted completed enhanced SEA reports. Evaluation data were collected through questionnaire, telephone interviews, and thematic analysis of SEA reports. Results: Overall, 149/240 care practitioners tested the guiding tools and submitted completed SEA reports (62.1%). Reported understanding of how to undertake SEA improved postintervention (P < .001), while most agreed that the Personal Booklet was practical (88/123, 71.5%) and relevant to dealing with related emotions (93/123, 75.6%). The Desk Pad tool helped focus the SEA on systems issues (85/123, 69.1%), while most found the Report Format clear (94/123, 76.4%) and would recommend it (88/123, 71.5%). Most SEA reports adopted a systems approach to analyses (125/149, 83.9%), care improvement (74/149, 49.7), or planned actions (42/149, 28.2%). Discussion: Applying human factors principles to SEA potentially enables care teams to gain a systems-based understanding of why things go wrong, which may help with related emotional demands and with more effective learning and improvement. PMID:27583996

  14. Enhancing the Effectiveness of Significant Event Analysis: Exploring Personal Impact and Applying Systems Thinking in Primary Care.

    PubMed

    Bowie, Paul; McNaughton, Elaine; Bruce, David; Holly, Deirdre; Forrest, Eleanor; Macleod, Marion; Kennedy, Susan; Power, Ailsa; Toppin, Denis; Black, Irene; Pooley, Janet; Taylor, Audrey; Swanson, Vivien; Kelly, Moya; Ferguson, Julie; Stirling, Suzanne; Wakeling, Judy; Inglis, Angela; McKay, John; Sargeant, Joan

    2016-01-01

    Significant event analysis (SEA) is well established in many primary care settings but can be poorly implemented. Reasons include the emotional impact on clinicians and limited knowledge of systems thinking in establishing why events happen and formulating improvements. To enhance SEA effectiveness, we developed and tested "guiding tools" based on human factors principles. Mixed-methods development of guiding tools (Personal Booklet-to help with emotional demands and apply a human factors analysis at the individual level; Desk Pad-to guide a team-based systems analysis; and a written Report Format) by a multiprofessional "expert" group and testing with Scottish primary care practitioners who submitted completed enhanced SEA reports. Evaluation data were collected through questionnaire, telephone interviews, and thematic analysis of SEA reports. Overall, 149/240 care practitioners tested the guiding tools and submitted completed SEA reports (62.1%). Reported understanding of how to undertake SEA improved postintervention (P < .001), while most agreed that the Personal Booklet was practical (88/123, 71.5%) and relevant to dealing with related emotions (93/123, 75.6%). The Desk Pad tool helped focus the SEA on systems issues (85/123, 69.1%), while most found the Report Format clear (94/123, 76.4%) and would recommend it (88/123, 71.5%). Most SEA reports adopted a systems approach to analyses (125/149, 83.9%), care improvement (74/149, 49.7), or planned actions (42/149, 28.2%). Applying human factors principles to SEA potentially enables care teams to gain a systems-based understanding of why things go wrong, which may help with related emotional demands and with more effective learning and improvement.

  15. A SYSTEMIC APPROACH TO MITIGATING URBAN STORM WATER RUNOFF VIA DEVELOPMENT PLANS BASED ON LAND SUITABILITY ANALYSIS

    EPA Science Inventory

    We advocate an approach to reduce the anticipated increase in stormwater runoff from conventional development by demonstrating a low-impact development that incorporates hydrologic factors into an expanded land suitability analysis. This methodology was applied to a 3 hectare exp...

  16. RANDOMIZATION PROCEDURES FOR THE ANALYSIS OF EDUCATIONAL EXPERIMENTS.

    ERIC Educational Resources Information Center

    COLLIER, RAYMOND O.

    CERTAIN SPECIFIC ASPECTS OF HYPOTHESIS TESTS USED FOR ANALYSIS OF RESULTS IN RANDOMIZED EXPERIMENTS WERE STUDIED--(1) THE DEVELOPMENT OF THE THEORETICAL FACTOR, THAT OF PROVIDING INFORMATION ON STATISTICAL TESTS FOR CERTAIN EXPERIMENTAL DESIGNS AND (2) THE DEVELOPMENT OF THE APPLIED ELEMENT, THAT OF SUPPLYING THE EXPERIMENTER WITH MACHINERY FOR…

  17. Applying the ICF framework to study changes in quality-of-life for youth with chronic conditions

    PubMed Central

    McDougall, Janette; Wright, Virginia; Schmidt, Jonathan; Miller, Linda; Lowry, Karen

    2011-01-01

    Objective The objective of this paper is to describe how the ICF framework was applied as the foundation for a longitudinal study of changes in quality-of-life (QoL) for youth with chronic conditions. Method This article will describe the study’s aims, methods, measures and data analysis techniques. It will point out how the ICF framework was used—and expanded upon—to provide a model for studying the impact of factors on changes in QoL for youth with chronic conditions. Further, it will describe the instruments that were chosen to measure the components of the ICF framework and the data analysis techniques that will be used to examine the impact of factors on changes in youths’ QoL. Conclusions Qualitative and longitudinal designs for studying QoL based on the ICF framework can be useful for unraveling the complex ongoing inter-relationships among functioning, contextual factors and individuals’ perceptions of their QoL. PMID:21034288

  18. Effective factors in providing holistic care: a qualitative study.

    PubMed

    Zamanzadeh, Vahid; Jasemi, Madineh; Valizadeh, Leila; Keogh, Brian; Taleghani, Fariba

    2015-01-01

    Holistic care is a comprehensive model of caring. Previous studies have shown that most nurses do not apply this method. Examining the effective factors in nurses' provision of holistic care can help with enhancing it. Studying these factors from the point of view of nurses will generate real and meaningful concepts and can help to extend this method of caring. A qualitative study was used to identify effective factors in holistic care provision. Data gathered by interviewing 14 nurses from university hospitals in Iran were analyzed with a conventional qualitative content analysis method and by using MAXQDA (professional software for qualitative and mixed methods data analysis) software. Analysis of data revealed three main themes as effective factors in providing holistic care: The structure of educational system, professional environment, and personality traits. Establishing appropriate educational, management systems, and promoting religiousness and encouragement will induce nurses to provide holistic care and ultimately improve the quality of their caring.

  19. The person's conception of the structures of developing intellect: early adolescence to middle age.

    PubMed

    Demetriou, A; Efklides, A

    1989-08-01

    According to experiential structuralism, thought abilities have six capacity spheres: experimental, propositional, quantitative, imaginal, qualitative, and metacognitive. The first five are applied to the environment. The metacognitive capacity is applied to the others, serving as the interface between reality and the cognitive system or between any of the other capacities. To test this postulate, 648 subjects aged 12 to 40 years, solved eight tasks that were addressed, in pairs, to the first four capacity spheres. One of the tasks in each pair tapped the first and the other the third formal level of the sphere. Having solved the tasks, the subjects were required to rate each pair of tasks in terms of similarity of operations, difficulty, and success of solution. Factor analysis of difficulty and success evaluation scores revealed the same capacity-specific factors as the analysis of performance scores. Factor analysis of similarity scores differentiated between same- and different-sphere pairs. Analysis of variance showed that difficulty and success evaluation scores preserved performance differences between the first and the third formal tasks. Cognitive level, age, socioeconomic status, and sex were related to the metacognitive measures in ways similar to their relations to performance measures. These findings were integrated into a model aimed at capturing real-time metacognitive functioning.

  20. A Conceptual Framework for the Analysis of Risk and Problem Behaviors: The Case of Adolescent Sexual Behavior

    ERIC Educational Resources Information Center

    Guilamo-Ramos; Vincent; Jaccard, James; Dittus, Patricia; Gonzalez, Bernardo; Bouris, Alida

    2008-01-01

    A framework for the analysis of adolescent problem behaviors was explicated that draws on five major theories of human behavior. The framework emphasizes intentions to perform behaviors and factors that influence intentions as well as moderate the impact of intentions on behavior. The framework was applied to the analysis of adolescent sexual risk…

  1. Development of Science Anxiety Scale for Primary School Students

    ERIC Educational Resources Information Center

    Guzeller, Cem Oktay; Dogru, Mustafa

    2012-01-01

    The principal aim of the study is to develop a new scale Science Anxiety Scale and to examine its the psychometric properties and construct validity of the Science Anxiety Scale in a sample of 797 primary school students. Exploratory factor analysis was applied and found to have a two-dimensional structure. Confirmatory factor analyses provide…

  2. Accelerating Tacit Knowledge Building of Client-Facing Consultants: Can Organizations Better Support These Learning Processes?

    ERIC Educational Resources Information Center

    McQueen, Robert J.; Janson, Annick

    2016-01-01

    Purpose: This paper aims to examine factors which influence how tacit knowledge is built and applied by client-facing consultants. Design/methodology/approach: Qualitative methods (interviews, thematic analysis) were used to gather and analyse data from 15 consultants in an agricultural extension context. Findings: Twenty-six factors about how…

  3. Standard Errors of Estimated Latent Variable Scores with Estimated Structural Parameters

    ERIC Educational Resources Information Center

    Hoshino, Takahiro; Shigemasu, Kazuo

    2008-01-01

    The authors propose a concise formula to evaluate the standard error of the estimated latent variable score when the true values of the structural parameters are not known and must be estimated. The formula can be applied to factor scores in factor analysis or ability parameters in item response theory, without bootstrap or Markov chain Monte…

  4. ADHD and Method Variance: A Latent Variable Approach Applied to a Nationally Representative Sample of College Freshmen

    ERIC Educational Resources Information Center

    Konold, Timothy R.; Glutting, Joseph J.

    2008-01-01

    This study employed a correlated trait-correlated method application of confirmatory factor analysis to disentangle trait and method variance from measures of attention-deficit/hyperactivity disorder obtained at the college level. The two trait factors were "Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition" ("DSM-IV")…

  5. The Analysis of the Impact of Individual Weighting Factor on Individual Scores

    ERIC Educational Resources Information Center

    Kilic, Gulsen Bagci; Cakan, Mehtap

    2006-01-01

    In this study, category-based self and peer assessment were applied twice in a semester in an Elementary Science Teaching Methods course in order to assess individual contributions of group members to group projects as well as to analyze the impact of Individual Weighting Factors (IWF) on individual scores and individual grades. IWF were…

  6. Attitude toward Science Teaching of Spanish and Turkish In-Service Elementary Teachers: Multi-Group Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Korur, Fikret; Vargas, Rocío Vargas; Torres Serrano, Noemí

    2016-01-01

    Elementary school teachers' having a positive attitude toward science teaching might encourage students to develop positive attitudes toward science learning. This cross-cultural study aimed to validate the seven-factor structure of the Dimensions of Attitude toward Science (DAS) scale by applying it in two countries. Moreover, it aimed to…

  7. Multiplication factor versus regression analysis in stature estimation from hand and foot dimensions.

    PubMed

    Krishan, Kewal; Kanchan, Tanuj; Sharma, Abhilasha

    2012-05-01

    Estimation of stature is an important parameter in identification of human remains in forensic examinations. The present study is aimed to compare the reliability and accuracy of stature estimation and to demonstrate the variability in estimated stature and actual stature using multiplication factor and regression analysis methods. The study is based on a sample of 246 subjects (123 males and 123 females) from North India aged between 17 and 20 years. Four anthropometric measurements; hand length, hand breadth, foot length and foot breadth taken on the left side in each subject were included in the study. Stature was measured using standard anthropometric techniques. Multiplication factors were calculated and linear regression models were derived for estimation of stature from hand and foot dimensions. Derived multiplication factors and regression formula were applied to the hand and foot measurements in the study sample. The estimated stature from the multiplication factors and regression analysis was compared with the actual stature to find the error in estimated stature. The results indicate that the range of error in estimation of stature from regression analysis method is less than that of multiplication factor method thus, confirming that the regression analysis method is better than multiplication factor analysis in stature estimation. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  8. Measuring Alexithymia via Trait Approach-I: A Alexithymia Scale Item Selection and Formation of Factor Structure

    PubMed Central

    TATAR, Arkun; SALTUKOĞLU, Gaye; ALİOĞLU, Seda; ÇİMEN, Sümeyye; GÜVEN, Hülya; AY, Çağla Ebru

    2017-01-01

    Introduction It is not clear in the literature whether available instruments are sufficient to measure alexithymia because of its theoretical structure. Moreover, it has been reported that several measuring instruments are needed to measure this construct, and all the instruments have different error sources. The old and the new forms of Toronto Alexithymia Scale are the only instruments available in Turkish. Thus, the purpose of this study was to develop a new scale to measure alexithymia, selecting items and constructing the factor structure. Methods A total of 1117 patients aged from 19 to 82 years (mean = 35.05 years) were included. A 100-item pool was prepared and applied to 628 women and 489 men. Data were analyzed using Explanatory Factor Analysis, Confirmatory Factor Analysis, and Item Response Theory and 28 items were selected. The new form of 28 items was applied to 415 university students, including 271 women and 144 men aged from 18 to 30 (mean=21.44). Results The results of Explanatory Factor Analysis revealed a five-factor construct of “Solving and Expressing Affective Experiences,” “External Locused Cognitive Style,” “Tendency to Somatize Affections,” “Imaginary Life and Visualization,” and “Acting Impulsively,” along with a two-factor construct representing the “Affective” and “Cognitive” components. All the components of the construct showed good model fit and high internal consistency. The new form was tested in terms of internal consistency, test-retest reliability, and concurrent validity using Toronto Alexithymia Scale as criteria and discriminative validity using Five-Factor Personality Inventory Short Form. Conclusion The results showed that the new scale met the basic psychometric requirements. Results have been discussed in line with related studies. PMID:29033633

  9. Effect of local and global geomagnetic activity on human cardiovascular homeostasis.

    PubMed

    Dimitrova, Svetla; Stoilova, Irina; Yanev, Toni; Cholakov, Ilia

    2004-02-01

    The authors investigated the effects of local and planetary geomagnetic activity on human physiology. They collected data in Sofia, Bulgaria, from a group of 86 volunteers during the periods of the autumnal and vernal equinoxes. They used the factors local/planetary geomagnetic activity, day of measurement, gender, and medication use to apply a four-factor multiple analysis of variance. They also used a post hoc analysis to establish the statistical significance of the differences between the average values of the measured physiological parameters in the separate factor levels. In addition, the authors performed correlation analysis between the physiological parameters examined and geophysical factors. The results revealed that geomagnetic changes had a statistically significant influence on arterial blood pressure. Participants expressed this reaction with weak local geomagnetic changes and when major and severe global geomagnetic storms took place.

  10. A refined method for multivariate meta-analysis and meta-regression

    PubMed Central

    Jackson, Daniel; Riley, Richard D

    2014-01-01

    Making inferences about the average treatment effect using the random effects model for meta-analysis is problematic in the common situation where there is a small number of studies. This is because estimates of the between-study variance are not precise enough to accurately apply the conventional methods for testing and deriving a confidence interval for the average effect. We have found that a refined method for univariate meta-analysis, which applies a scaling factor to the estimated effects’ standard error, provides more accurate inference. We explain how to extend this method to the multivariate scenario and show that our proposal for refined multivariate meta-analysis and meta-regression can provide more accurate inferences than the more conventional approach. We explain how our proposed approach can be implemented using standard output from multivariate meta-analysis software packages and apply our methodology to two real examples. © 2013 The Authors. Statistics in Medicine published by John Wiley & Sons, Ltd. PMID:23996351

  11. Can Nursing Students Practice What Is Preached? Factors Impacting Graduating Nurses' Abilities and Achievement to Apply Evidence-Based Practices.

    PubMed

    Blackman, Ian R; Giles, Tracey M

    2017-04-01

    In order to meet national Australian nursing registration requisites, nurses need to meet competency requirements for evidence-based practices (EBPs). A hypothetical model was formulated to explore factors that influenced Australian nursing students' ability and achievement to understand and employ EBPs related to health care provision. A nonexperimental, descriptive survey method was used to identify self-reported EBP efficacy estimates of 375 completing undergraduate nursing students. Factors influencing participants' self-rated EBP abilities were validated by Rasch analysis and then modeled using the partial least squares analysis (PLS Path) program. Graduating nursing students' ability to understand and apply EBPs for clinical improvement can be directly and indirectly predicted by eight variables including their understanding in the analysis, critique and synthesis of clinically based nursing research, their ability to communicate research to others and whether they had actually witnessed other staff delivering EBP. Forty-one percent of the variance in the nursing students' self-rated EBP efficacy scores is able to be accounted for by this model. Previous exposure to EBP studies facilitates participants' confidence with EBP, particularly with concurrent clinical EBP experiences. © 2017 Sigma Theta Tau International.

  12. Determination of pKa values of some antipsychotic drugs by HPLC--correlations with the Kamlet and taft solvatochromic parameters and HPLC analysis in dosage forms.

    PubMed

    Sanli, Senem; Akmese, Bediha; Altun, Yuksel

    2013-01-01

    In this study, ionization constant (pKa) values were determined by using the dependence of the retention factor on the pH of the mobile phase for four ionizable drugs, namely, risperidone (RI), clozapine (CL), olanzapine (OL), and sertindole (SE). The effect of the mobile phase composition on the pKa was studied by measuring the pKa at different acetonitrile-water mixtures in an HPLC-UV method. To explain the variation of the pKa values obtained over the whole composition range studied, the quasi-lattice quasi-chemical theory of preferential solvation was applied. The pKa values of drugs were correlated with the Kamlet and Taft solvatochromic parameters. Kamlet and Taft's general equation was reduced to two terms by using combined factor analysis and target factor analysis in these mixtures: the independent term and the hydrogen-bond donating ability a. The HPLC-UV method was successfully applied for the determination of RI, OL, and SE in pharmaceutical dosage forms. CL was chosen as an internal standard. Additionally, the repeatability, reproducibility, selectivity, precision, and accuracy of the method in all media were investigated and calculated.

  13. Ready, willing, and able to divorce: an economic and cultural history of divorce in twentieth-century Sweden.

    PubMed

    Simonsson, Per; Sandström, Glenn

    2011-01-01

    This study outlines a long history of divorce in Sweden, recognizing the importance of considering both economic and cultural factors in the analysis of marital dissolution. Following Ansley Coale, the authors examine how a framework of multiple theoretical constructs, in interaction, can be applied to the development toward mass divorce. Applying a long historical perspective, the authors argue that an analysis of gendered aspects of the interaction between culture and economics is crucial for the understanding of the rise of mass divorce. The empirical analysis finds support for a marked decrease in legal and cultural obstacles to divorce already during the first decades of the twentieth century. However, economic structures remained a severe obstacle that prohibited significant increases in divorce rate prior to World War II. It was only during the 1940s and 1960s, when cultural change was complemented by marked decreases in economic interdependence between spouses, that the divorce rate exhibited significant increases. The authors find that there are advantages to looking at the development of divorce as a history in which multiple empirical factors are examined in conjunction, recognizing that these factors played different roles during different time periods.

  14. Space operations and the human factor

    NASA Astrophysics Data System (ADS)

    Brody, Adam R.

    1993-10-01

    Although space flight does not put the public at high risk, billions of dollars in hardware are destroyed and the space program halted when an accident occurs. Researchers are therefore applying human-factors techniques similar to those used in the aircraft industry, albeit at a greatly reduced level, to the spacecraft environment. The intent is to reduce the likelihood of catastrophic failure. To increase safety and efficiency, space human factors researchers have simulated spacecraft docking and extravehicular activity rescue. Engineers have also studied EVA suit mobility and aids. Other basic human-factors issues that have been applied to the space environment include antropometry, biomechanics, and ergonomics. Workstation design, workload, and task analysis currently receive much attention, as do habitability and other aspects of confined environments. Much work also focuses on individual payloads, as each presents its own complexities.

  15. A decision model for selecting sustainable drinking water supply and greywater reuse systems for developing communities with a case study in Cimahi, Indonesia.

    PubMed

    Henriques, Justin J; Louis, Garrick E

    2011-01-01

    Capacity Factor Analysis is a decision support system for selection of appropriate technologies for municipal sanitation services in developing communities. Developing communities are those that lack the capability to provide adequate access to one or more essential services, such as water and sanitation, to their residents. This research developed two elements of Capacity Factor Analysis: a capacity factor based classification for technologies using requirements analysis, and a matching policy for choosing technology options. First, requirements analysis is used to develop a ranking for drinking water supply and greywater reuse technologies. Second, using the Capacity Factor Analysis approach, a matching policy is developed to guide decision makers in selecting the appropriate drinking water supply or greywater reuse technology option for their community. Finally, a scenario-based informal hypothesis test is developed to assist in qualitative model validation through case study. Capacity Factor Analysis is then applied in Cimahi Indonesia as a form of validation. The completed Capacity Factor Analysis model will allow developing communities to select drinking water supply and greywater reuse systems that are safe, affordable, able to be built and managed by the community using local resources, and are amenable to expansion as the community's management capacity increases. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. A new technique for ordering asymmetrical three-dimensional data sets in ecology.

    PubMed

    Pavoine, Sandrine; Blondel, Jacques; Baguette, Michel; Chessel, Daniel

    2007-02-01

    The aim of this paper is to tackle the problem that arises from asymmetrical data cubes formed by two crossed factors fixed by the experimenter (factor A and factor B, e.g., sites and dates) and a factor which is not controlled for (the species). The entries of this cube are densities in species. We approach this kind of data by the comparison of patterns, that is to say by analyzing first the effect of factor B on the species-factor A pattern, and second the effect of factor A on the species-factor B pattern. The analysis of patterns instead of individual responses requires a correspondence analysis. We use a method we call Foucart's correspondence analysis to coordinate the correspondence analyses of several independent matrices of species x factor A (respectively B) type, corresponding to each modality of factor B (respectively A). Such coordination makes it possible to evaluate the effect of factor B (respectively A) on the species-factor A (respectively B) pattern. The results obtained by such a procedure are much more insightful than those resulting from a classical single correspondence analysis applied to the global matrix that is obtained by simply unrolling the data cube, juxtaposing for example the individual species x factor A matrices through modalities of factor B. This is because a single global correspondence analysis combines three effects of factors in a way that cannot be determined from factorial maps (factor A, factor B, and factor A x factor B interaction) whereas the applications of Foucart's correspondence analysis clearly discriminate two different issues. Using two data sets, we illustrate that this technique proves to be particularly powerful in the analyses of ecological convergence which include several distinct data sets and in the analyses of spatiotemporal variations of species distributions.

  17. Potential barriers to the application of multi-factor portfolio analysis in public hospitals: evidence from a pilot study in the Netherlands.

    PubMed

    Pavlova, Milena; Tsiachristas, Apostolos; Vermaeten, Gerhard; Groot, Wim

    2009-01-01

    Portfolio analysis is a business management tool that can assist health care managers to develop new organizational strategies. The application of portfolio analysis to US hospital settings has been frequently reported. In Europe however, the application of this technique has received little attention, especially concerning public hospitals. Therefore, this paper examines the peculiarities of portfolio analysis and its applicability to the strategic management of European public hospitals. The analysis is based on a pilot application of a multi-factor portfolio analysis in a Dutch university hospital. The nature of portfolio analysis and the steps in a multi-factor portfolio analysis are reviewed along with the characteristics of the research setting. Based on these data, a multi-factor portfolio model is developed and operationalized. The portfolio model is applied in a pilot investigation to analyze the market attractiveness and hospital strengths with regard to the provision of three orthopedic services: knee surgery, hip surgery, and arthroscopy. The pilot portfolio analysis is discussed to draw conclusions about potential barriers to the overall adoption of portfolio analysis in the management of a public hospital. Copyright (c) 2008 John Wiley & Sons, Ltd.

  18. Critical incident technique analysis applied to perianesthetic cardiac arrests at a university teaching hospital.

    PubMed

    Hofmeister, Erik H; Reed, Rachel A; Barletta, Michele; Shepard, Molly; Quandt, Jane

    2018-05-01

    To apply the critical incident technique (CIT) methodology to a series of perianesthetic cardiac arrest events at a university teaching hospital to describe the factors that contributed to cardiac arrest. CIT qualitative analysis of a case series. A group of 16 dogs and cats that suffered a perioperative cardiac arrest between November 2013 and November 2016. If an arrest occurred, the event was discussed among the anesthesiologists. The discussion included a description of the case, a description of the sequence of events leading up to the arrest and a discussion of what could have been done to affect the outcome. A written description of the case and the event including animal signalment and a timeline of events was provided by the supervising anesthesiologist following discussion among the anesthesiologists. Only dogs or cats were included. After the data collection period, information from the medical record was collected. A qualitative document analysis was performed on the summaries provided about each case by the supervising anesthesiologist, the medical record and any supporting documents. Each case was then classified into one or more of the following: animal, human, equipment, drug and procedural factors for cardiac arrest. The most common factor was animal (n=14), followed by human (n=12), procedural (n=4), drugs (n=1) and equipment (n=1). The majority (n=11) of animals had multiple factors identified. Cardiac arrests during anesthesia at a referral teaching hospital were primarily a result of animal and human factors. Arrests because of procedural, drug and equipment factors were uncommon. Most animals experienced more than one factor and two animals arrested after a change in recumbency. Future work should focus on root cause analysis and interventions designed to minimize all factors, particularly human ones. Copyright © 2018 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

  19. Defeat and entrapment: more than meets the eye? Applying network analysis to estimate dimensions of highly correlated constructs.

    PubMed

    Forkmann, Thomas; Teismann, Tobias; Stenzel, Jana-Sophie; Glaesmer, Heide; de Beurs, Derek

    2018-01-25

    Defeat and entrapment have been shown to be of central relevance to the development of different disorders. However, it remains unclear whether they represent two distinct constructs or one overall latent variable. One reason for the unclarity is that traditional factor analytic techniques have trouble estimating the right number of clusters in highly correlated data. In this study, we applied a novel approach based on network analysis that can deal with correlated data to establish whether defeat and entrapment are best thought of as one or multiple constructs. Explanatory graph analysis was used to estimate the number of dimensions within the 32 items that make up the defeat and entrapment scales in two samples: an online community sample of 480 participants, and a clinical sample of 147 inpatients admitted to a psychiatric hospital after a suicidal attempt or severe suicidal crisis. Confirmatory Factor analysis (CFA) was used to test whether the proposed structure fits the data. In both samples, bootstrapped exploratory graph analysis suggested that the defeat and entrapment items belonged to different dimensions. Within the entrapment items, two separate dimensions were detected, labelled internal and external entrapment. Defeat appeared to be multifaceted only in the online sample. When comparing the CFA outcomes of the one, two, three and four factor models, the one factor model was preferred. Defeat and entrapment can be viewed as distinct, yet, highly associated constructs. Thus, although replication is needed, results are in line with theories differentiating between these two constructs.

  20. Development and Validation of a Behavioral Screener for Preschool-Age Children

    ERIC Educational Resources Information Center

    DiStefano, Christine A.; Kamphaus, Randy W.

    2007-01-01

    The purpose of this study was to document the development of a short behavioral scale that could be used to assess preschoolers' behavior while still retaining adequate scale coverage, reliability, and validity. Factor analysis and item analysis techniques were applied to data from a nationally representative, normative database to create a…

  1. 40 CFR 1037.243 - Demonstrating compliance with evaporative emission standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... standards in subpart B of this part if you prepare an engineering analysis showing that your vehicles in the... evaporative emission family is deemed not to comply if your engineering analysis is not adequate to show that... standard. (c) To compare emission levels with emission standards, apply deterioration factors to the...

  2. Cost-effectiveness of vaccination against cervical cancer: a multi-regional analysis assessing the impact of vaccine characteristics and alternative vaccination scenarios.

    PubMed

    Suárez, Eugenio; Smith, Jennifer S; Bosch, F Xavier; Nieminen, Pekka; Chen, Chien-Jen; Torvinen, Saku; Demarteau, Nadia; Standaert, Baudouin

    2008-09-15

    Mathematical models provide valuable insights into the public health and economic impact of cervical cancer vaccination programmes. An in-depth economic analysis should explore the effects of different vaccine-related factors and vaccination scenarios (independent of screening practices) on health benefits and costs. In this analysis, a Markov cohort model was used to explore the impact of vaccine characteristics (e.g. cross-type protection and waning of immunity) and different vaccination scenarios (e.g. age at vaccination and multiple cohort strategies) on the cost-effectiveness results of cervical cancer vaccination programmes. The analysis was applied across different regions in the world (Chile, Finland, Ireland, Poland and Taiwan) to describe the influence of location-specific conditions. The results indicate that in all the different settings cervical cancer vaccination becomes more cost-effective with broader and sustained vaccine protection, with vaccination at younger ages, and with the inclusion of several cohorts. When other factors were varied, the cost-effectiveness of vaccination was most negatively impacted by increasing the discount rate applied to costs and health effects.

  3. Risk analysis of gravity dam instability using credibility theory Monte Carlo simulation model.

    PubMed

    Xin, Cao; Chongshi, Gu

    2016-01-01

    Risk analysis of gravity dam stability involves complicated uncertainty in many design parameters and measured data. Stability failure risk ratio described jointly by probability and possibility has deficiency in characterization of influence of fuzzy factors and representation of the likelihood of risk occurrence in practical engineering. In this article, credibility theory is applied into stability failure risk analysis of gravity dam. Stability of gravity dam is viewed as a hybrid event considering both fuzziness and randomness of failure criterion, design parameters and measured data. Credibility distribution function is conducted as a novel way to represent uncertainty of influence factors of gravity dam stability. And combining with Monte Carlo simulation, corresponding calculation method and procedure are proposed. Based on a dam section, a detailed application of the modeling approach on risk calculation of both dam foundation and double sliding surfaces is provided. The results show that, the present method is feasible to be applied on analysis of stability failure risk for gravity dams. The risk assessment obtained can reflect influence of both sorts of uncertainty, and is suitable as an index value.

  4. Evaluation of the comprehensive palatability of Japanese sake paired with dishes by multiple regression analysis based on subdomains.

    PubMed

    Nakamura, Ryo; Nakano, Kumiko; Tamura, Hiroyasu; Mizunuma, Masaki; Fushiki, Tohru; Hirata, Dai

    2017-08-01

    Many factors contribute to palatability. In order to evaluate the palatability of Japanese alcohol sake paired with certain dishes by integrating multiple factors, here we applied an evaluation method previously reported for palatability of cheese by multiple regression analysis based on 3 subdomain factors (rewarding, cultural, and informational). We asked 94 Japanese participants/subjects to evaluate the palatability of sake (1st evaluation/E1 for the first cup, 2nd/E2 and 3rd/E3 for the palatability with aftertaste/afterglow of certain dishes) and to respond to a questionnaire related to 3 subdomains. In E1, 3 factors were extracted by a factor analysis, and the subsequent multiple regression analyses indicated that the palatability of sake was interpreted by mainly the rewarding. Further, the results of attribution-dissections in E1 indicated that 2 factors (rewarding and informational) contributed to the palatability. Finally, our results indicated that the palatability of sake was influenced by the dish eaten just before drinking.

  5. Mining Predictors of Success in Air Force Flight Training Regiments via Semantic Analysis of Instructor Evaluations

    DTIC Science & Technology

    2018-03-01

    We apply our methodology to the criticism text written in the flight-training program student evaluations in order to construct a model that...factors. We apply our methodology to the criticism text written in the flight-training program student evaluations in order to construct a model...9 D. BINARY CLASSIFICATION AND FEATURE SELECTION ..........11 III. METHODOLOGY

  6. Mapping Change Management: A Co-citation Analysis

    DTIC Science & Technology

    2007-03-01

    found that both had the recurring theme of corporate management and change; while factor four focused on investments, acquisitions and finances and...L. (2004). Corporate governance of Japanese banks. Journal of Corporate Finance , 10(3), 327-354. Angle, H. L., Manz, C. C., & Vandeven, A. H. (1985...Science Quarterly, Annual Review of Psychology, Industrial and Corporate Change, The Journal of Applied Behavioral Science, Journal of Applied Psychology

  7. Investigation of effects of process parameters on properties of friction stir welded joints

    NASA Astrophysics Data System (ADS)

    Chauhan, Atul; Soota, Tarun; Rajput, S. K.

    2018-03-01

    This work deals with application of friction stir welding (FSW) using application of Taguchi orthogonal array. FSW procedure is used for joining the aluminium alloy AA6063-T0 plates in butt configuration with orthogonal combination of factors and their levels. The combination of factors involving tool rotation speed, tool travel speed and tool pin profile are used in three levels. Grey relational analysis (GRA) has been applied to select optimum level of factors for optimising UTS, ductility and hardness of joint. Experiments have been conducted with two different tool materials (HSS and HCHCr steel) with various factors level combinations for joining AA6063-T0. On the basis of grey relational grades at different levels of factors and analysis of variance (ANOVA) ideal combination of factors are determined. The influence of tool material is also studied.

  8. [SWOT analysis: the analytical method in the process of planning and its application in the development of orthopaedic hospital department].

    PubMed

    Terzić, Zorica; Vukasinović, Zoran; Bjegović-Mikanović, Vesna; Jovanović, Vesna; Janicić, Radmila

    2010-01-01

    SWOT analysis is a managerial tool used to evaluate internal and external environment through strengths and weaknesses, opportunities and threats. The aim was to demonstrate the application of the SWOT analysis on the example of the Department for Paediatric Orthopaedics and Traumatology at the Institute of Orthopaedic Surgery "Banjica" in Belgrade. Qualitative research was conducted during December 2008 at the Department for Paediatric Orthopaedics and Traumatology of the Institute of Orthopaedic Surgery "Banjica" by applying the focus group technique. Participants were members of the medical staff and patients. In the first phase of the focus group brainstorming was applied to collect the factors of internal and external environment, and to identify strengths and weaknesses, opportunities and threats, respectively. In the second phase the nominal group technique was applied in order to reduce the list of factors. The factors were assessed according to their influence on the Department. Factors ranked by the three point Likert scale from 3 (highest impact) to 1 (lowest impact). The most important strengths of the Department are competent and skilled staff, high quality of services, average hospital bed utilization, the Department providing the educational basis of the School of Medicine, satisfied patients, pleasant setting, and additional working hours. The weaknesses are: poor spatial organization, personnel unmotivated to refresh knowledge, lack of specifically trained personnel, inadequate sanitary facilities, and uncovered services by the Insurance Fund, long average hospital stay, and low economic status of patients. The opportunities are: legislative regulations, formed paediatric traumatology service at the City level, good regional position of the Institute, and extension of referral areas. The threats are: absent Department autonomy in the personnel policy of the Institute, competitions within the Institute, impossibility to increase the Department capacities, inadequate nutrition, low opportunities for expert training of the personnel, outdated equipment, and presence of informal payments. SWOT analysis is a frequently used managerial instrument, which enables the systematic approach in decision making process.

  9. Genomic analysis of regulatory network dynamics reveals large topological changes

    NASA Astrophysics Data System (ADS)

    Luscombe, Nicholas M.; Madan Babu, M.; Yu, Haiyuan; Snyder, Michael; Teichmann, Sarah A.; Gerstein, Mark

    2004-09-01

    Network analysis has been applied widely, providing a unifying language to describe disparate systems ranging from social interactions to power grids. It has recently been used in molecular biology, but so far the resulting networks have only been analysed statically. Here we present the dynamics of a biological network on a genomic scale, by integrating transcriptional regulatory information and gene-expression data for multiple conditions in Saccharomyces cerevisiae. We develop an approach for the statistical analysis of network dynamics, called SANDY, combining well-known global topological measures, local motifs and newly derived statistics. We uncover large changes in underlying network architecture that are unexpected given current viewpoints and random simulations. In response to diverse stimuli, transcription factors alter their interactions to varying degrees, thereby rewiring the network. A few transcription factors serve as permanent hubs, but most act transiently only during certain conditions. By studying sub-network structures, we show that environmental responses facilitate fast signal propagation (for example, with short regulatory cascades), whereas the cell cycle and sporulation direct temporal progression through multiple stages (for example, with highly inter-connected transcription factors). Indeed, to drive the latter processes forward, phase-specific transcription factors inter-regulate serially, and ubiquitously active transcription factors layer above them in a two-tiered hierarchy. We anticipate that many of the concepts presented here-particularly the large-scale topological changes and hub transience-will apply to other biological networks, including complex sub-systems in higher eukaryotes.

  10. Confirmation of the Three-Factor Model of Problematic Internet Use on Off-Line Adolescent and Adult Samples

    PubMed Central

    Koronczai, Beatrix; Urbán, Róbert; Kökönyei, Gyöngyi; Paksi, Borbála; Papp, Krisztina; Kun, Bernadette; Arnold, Petra; Kállai, János

    2011-01-01

    Abstract As the Internet became widely used, problems associated with its excessive use became increasingly apparent. Although for the assessment of these problems several models and related questionnaires have been elaborated, there has been little effort made to confirm them. The aim of the present study was to test the three-factor model of the previously created Problematic Internet Use Questionnaire (PIUQ) by data collection methods formerly not applied (off-line group and face-to-face settings), on the one hand, and by testing on different age groups (adolescent and adult representative samples), on the other hand. Data were collected from 438 high-school students (44.5 percent boys; mean age: 16.0 years; standard deviation=0.7 years) and also from 963 adults (49.9 percent males; mean age: 33.6 years; standard deviation=11.8 years). We applied confirmatory factor analysis to confirm the measurement model of problematic Internet use. The results of the analyses carried out inevitably support the original three-factor model over the possible one-factor solution. Using latent profile analysis, we identified 11 percent of adults and 18 percent of adolescent users characterized by problematic use. Based on exploratory factor analysis, we also suggest a short form of the PIUQ consisting of nine items. Both the original 18-item version of PIUQ and its short 9-item form have satisfactory reliability and validity characteristics, and thus, they are suitable for the assessment of problematic Internet use in future studies. PMID:21711129

  11. Application of multivariable statistical techniques in plant-wide WWTP control strategies analysis.

    PubMed

    Flores, X; Comas, J; Roda, I R; Jiménez, L; Gernaey, K V

    2007-01-01

    The main objective of this paper is to present the application of selected multivariable statistical techniques in plant-wide wastewater treatment plant (WWTP) control strategies analysis. In this study, cluster analysis (CA), principal component analysis/factor analysis (PCA/FA) and discriminant analysis (DA) are applied to the evaluation matrix data set obtained by simulation of several control strategies applied to the plant-wide IWA Benchmark Simulation Model No 2 (BSM2). These techniques allow i) to determine natural groups or clusters of control strategies with a similar behaviour, ii) to find and interpret hidden, complex and casual relation features in the data set and iii) to identify important discriminant variables within the groups found by the cluster analysis. This study illustrates the usefulness of multivariable statistical techniques for both analysis and interpretation of the complex multicriteria data sets and allows an improved use of information for effective evaluation of control strategies.

  12. Human Factors Research in Anesthesia Patient Safety

    PubMed Central

    Weinger, Matthew B.; Slagle, Jason

    2002-01-01

    Patient safety has become a major public concern. Human factors research in other high-risk fields has demonstrated how rigorous study of factors that affect job performance can lead to improved outcome and reduced errors after evidence-based redesign of tasks or systems. These techniques have increasingly been applied to the anesthesia work environment. This paper describes data obtained recently using task analysis and workload assessment during actual patient care and the use of cognitive task analysis to study clinical decision making. A novel concept of “non-routine events” is introduced and pilot data are presented. The results support the assertion that human factors research can make important contributions to patient safety. Information technologies play a key role in these efforts.

  13. Human factors research in anesthesia patient safety.

    PubMed Central

    Weinger, M. B.; Slagle, J.

    2001-01-01

    Patient safety has become a major public concern. Human factors research in other high-risk fields has demonstrated how rigorous study of factors that affect job performance can lead to improved outcome and reduced errors after evidence-based redesign of tasks or systems. These techniques have increasingly been applied to the anesthesia work environment. This paper describes data obtained recently using task analysis and workload assessment during actual patient care and the use of cognitive task analysis to study clinical decision making. A novel concept of "non-routine events" is introduced and pilot data are presented. The results support the assertion that human factors research can make important contributions to patient safety. Information technologies play a key role in these efforts. PMID:11825287

  14. Inflammatory Gene Regulatory Networks in Amnion Cells Following Cytokine Stimulation: Translational Systems Approach to Modeling Human Parturition

    PubMed Central

    Summerfield, Taryn L.; Yu, Lianbo; Gulati, Parul; Zhang, Jie; Huang, Kun; Romero, Roberto; Kniss, Douglas A.

    2011-01-01

    A majority of the studies examining the molecular regulation of human labor have been conducted using single gene approaches. While the technology to produce multi-dimensional datasets is readily available, the means for facile analysis of such data are limited. The objective of this study was to develop a systems approach to infer regulatory mechanisms governing global gene expression in cytokine-challenged cells in vitro, and to apply these methods to predict gene regulatory networks (GRNs) in intrauterine tissues during term parturition. To this end, microarray analysis was applied to human amnion mesenchymal cells (AMCs) stimulated with interleukin-1β, and differentially expressed transcripts were subjected to hierarchical clustering, temporal expression profiling, and motif enrichment analysis, from which a GRN was constructed. These methods were then applied to fetal membrane specimens collected in the absence or presence of spontaneous term labor. Analysis of cytokine-responsive genes in AMCs revealed a sterile immune response signature, with promoters enriched in response elements for several inflammation-associated transcription factors. In comparison to the fetal membrane dataset, there were 34 genes commonly upregulated, many of which were part of an acute inflammation gene expression signature. Binding motifs for nuclear factor-κB were prominent in the gene interaction and regulatory networks for both datasets; however, we found little evidence to support the utilization of pathogen-associated molecular pattern (PAMP) signaling. The tissue specimens were also enriched for transcripts governed by hypoxia-inducible factor. The approach presented here provides an uncomplicated means to infer global relationships among gene clusters involved in cellular responses to labor-associated signals. PMID:21655103

  15. Convergence Estimates for Multidisciplinary Analysis and Optimization

    NASA Technical Reports Server (NTRS)

    Arian, Eyal

    1997-01-01

    A quantitative analysis of coupling between systems of equations is introduced. This analysis is then applied to problems in multidisciplinary analysis, sensitivity, and optimization. For the sensitivity and optimization problems both multidisciplinary and single discipline feasibility schemes are considered. In all these cases a "convergence factor" is estimated in terms of the Jacobians and Hessians of the system, thus it can also be approximated by existing disciplinary analysis and optimization codes. The convergence factor is identified with the measure for the "coupling" between the disciplines in the system. Applications to algorithm development are discussed. Demonstration of the convergence estimates and numerical results are given for a system composed of two non-linear algebraic equations, and for a system composed of two PDEs modeling aeroelasticity.

  16. Human factors analysis and classification system applied to civil aircraft accidents in India.

    PubMed

    Gaur, Deepak

    2005-05-01

    The Human Factors Analysis and Classification System (HFACS) has gained wide acceptance as a tool to classify human factors in aircraft accidents and incidents. This study on application of HFACS to civil aircraft accident reports at Directorate General Civil of Aviation (DGCA), India, was conducted to ascertain the practicability of applying HFACS to existing investigation reports and to analyze the trends of human factor causes of civil aircraft accidents. Accident investigation reports held at DGCA, New Delhi, for the period 1990--99 were scrutinized. In all, 83 accidents occurred during this period, of which 48 accident reports were evaluated in this study. One or more human factors contributed to 37 of the 48 (77.1%) accidents. The commonest unsafe act was 'skill based errors' followed by 'decision errors.' Violations of laid down rules were contributory in 16 cases (33.3%). 'Preconditions for unsafe acts' were seen in 23 of the 48 cases (47.9%). A fairly large number (52.1%) had 'organizational influences' contributing to the accident. These results are in consonance with larger studies of accidents in the U.S. Navy and general aviation. Such a high percentage of 'organizational influences' has not been reported in other studies. This is a healthy sign for Indian civil aviation, provided effective remedial action for the same is undertaken.

  17. [Applications of habitat equivalency analysis in ecological damage assessment of oil spill incident].

    PubMed

    Yang, Yin; Han, Da-xiong; Wang, Hai-yan

    2011-08-01

    Habitat equivalency analysis (HEA) is one of the methods commonly used by U.S. National Oceanic and Atmospheric Administration in natural resources damage assessment, but rarely applied in China. Based on the theory of HEA and the assessment practices of domestic oil spill incidents, a modification on the HEA was made in this paper, and applied to calculate the habitat value in oil spill incidents. According to the data collected from an oil spill incident in China, the modified HEA was applied in a case study to scale the compensatory-restoration. By introducing the ecological service equivalent factor to transfer various habitats, it was achieved to value of the injured habitats in ecological damage assessment of oil spill incident.

  18. Factors Affecting Higher Order Thinking Skills of Students: A Meta-Analytic Structural Equation Modeling Study

    ERIC Educational Resources Information Center

    Budsankom, Prayoonsri; Sawangboon, Tatsirin; Damrongpanit, Suntorapot; Chuensirimongkol, Jariya

    2015-01-01

    The purpose of the research is to develop and identify the validity of factors affecting higher order thinking skills (HOTS) of students. The thinking skills can be divided into three types: analytical, critical, and creative thinking. This analysis is done by applying the meta-analytic structural equation modeling (MASEM) based on a database of…

  19. Conceptualizing and Measuring Weekend versus Weekday Alcohol Use: Item Response Theory and Confirmatory Factor Analysis

    PubMed Central

    Handren, Lindsay; Crano, William D.

    2018-01-01

    Culturally, people tend to abstain from alcohol intake during the weekdays and wait to consume in greater frequency and quantity during the weekends. The current research sought to empirically justify the days representing weekday versus weekend alcohol consumption. In study 1 (N = 419), item response theory was applied to a two-parameter (difficulty and discrimination) model that evaluated the days of drinking (frequency) during the typical 7-day week. Item characteristic curves were most similar for Monday, Tuesday, and Wednesday (prototypical weekday) and for Friday and Saturday (prototypical weekend). Thursday and Sunday, however, exhibited item characteristics that bordered the properties of weekday and weekend consumption. In study 2 (N = 403), confirmatory factor analysis was applied to test six hypothesized measurement structures representing drinks per day (quantity) during the typical week. The measurement model producing the strongest fit indices was a correlated two-factor structure involving separate weekday and weekend factors that permitted Thursday and Sunday to double load on both dimensions. The proper conceptualization and accurate measurement of the days demarcating the normative boundaries of “dry” weekdays and “wet” weekends are imperative to inform research and prevention efforts targeting temporal alcohol intake patterns. PMID:27488456

  20. Conceptualizing and Measuring Weekend versus Weekday Alcohol Use: Item Response Theory and Confirmatory Factor Analysis.

    PubMed

    Lac, Andrew; Handren, Lindsay; Crano, William D

    2016-10-01

    Culturally, people tend to abstain from alcohol intake during the weekdays and wait to consume in greater frequency and quantity during the weekends. The current research sought to empirically justify the days representing weekday versus weekend alcohol consumption. In study 1 (N = 419), item response theory was applied to a two-parameter (difficulty and discrimination) model that evaluated the days of drinking (frequency) during the typical 7-day week. Item characteristic curves were most similar for Monday, Tuesday, and Wednesday (prototypical weekday) and for Friday and Saturday (prototypical weekend). Thursday and Sunday, however, exhibited item characteristics that bordered the properties of weekday and weekend consumption. In study 2 (N = 403), confirmatory factor analysis was applied to test six hypothesized measurement structures representing drinks per day (quantity) during the typical week. The measurement model producing the strongest fit indices was a correlated two-factor structure involving separate weekday and weekend factors that permitted Thursday and Sunday to double load on both dimensions. The proper conceptualization and accurate measurement of the days demarcating the normative boundaries of "dry" weekdays and "wet" weekends are imperative to inform research and prevention efforts targeting temporal alcohol intake patterns.

  1. Population-Based Questionnaire Survey on Health Effects of Aircraft Noise on Residents Living around U.S. Airfields in the RYUKYUS—PART II: AN Analysis of the Discriminant Score and the Factor Score

    NASA Astrophysics Data System (ADS)

    HIRAMATSU, K.; MATSUI, T.; MIYAKITA, T.; ITO, A.; TOKUYAMA, T.; OSADA, Y.; YAMAMOTO, T.

    2002-02-01

    Discriminant function values of psychosomatics and neurosis are calculated using the 12 scale scores of the Todai Health Index, a general health questionnaire, obtained in the survey done around the Kadena and Futenma U.S. airfields in Okinawa, Japan. The total number of answers available for the analysis is 6301. Factor analysis is applied to the 12 scale scores by means of the principal factor method, and Oblimin rotation is done because the factors extracted are considered likely to correlate with each other to a greater or lesser extent. The logistic regression analysis is made with the independent variables of discriminant function (DF) values and factor scores and with the dependent variables of Ldn, age (six levels), sex, occupation (four categories) and the interaction of age and sex. Results indicate that the odds ratio of the DF values regarding psychosomatic disorder and of the score of somatic factor have clear dose-response relationship. The odds ratios of the DF value of neurosis and of the score of the mental factor increase in the area where noise exposure is very intense.

  2. The Influence of Accreditation on the Sustainability of Organizations with the Brazilian Accreditation Methodology

    PubMed Central

    de Paiva, Anderson Paulo

    2018-01-01

    This research evaluates the influence of the Brazilian accreditation methodology on the sustainability of the organizations. Critical factors for implementing accreditation were also examined, including measuring the relationships established between these factors in the organization sustainability. The present study was developed based on the survey methodology applied in the organizations accredited by ONA (National Accreditation Organization); 288 responses were received from the top level managers. The analysis of quantitative data of the measurement models was made with factorial analysis from principal components. The final model was evaluated from the confirmatory factorial analysis and structural equation modeling techniques. The results from the research are vital for the definition of factors that interfere in the accreditation processes, providing a better understanding for accredited organizations and for Brazilian accreditation. PMID:29599939

  3. Latent human error analysis and efficient improvement strategies by fuzzy TOPSIS in aviation maintenance tasks.

    PubMed

    Chiu, Ming-Chuan; Hsieh, Min-Chih

    2016-05-01

    The purposes of this study were to develop a latent human error analysis process, to explore the factors of latent human error in aviation maintenance tasks, and to provide an efficient improvement strategy for addressing those errors. First, we used HFACS and RCA to define the error factors related to aviation maintenance tasks. Fuzzy TOPSIS with four criteria was applied to evaluate the error factors. Results show that 1) adverse physiological states, 2) physical/mental limitations, and 3) coordination, communication, and planning are the factors related to airline maintenance tasks that could be addressed easily and efficiently. This research establishes a new analytic process for investigating latent human error and provides a strategy for analyzing human error using fuzzy TOPSIS. Our analysis process complements shortages in existing methodologies by incorporating improvement efficiency, and it enhances the depth and broadness of human error analysis methodology. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  4. Network Analysis: A Novel Approach to Understand Suicidal Behaviour

    PubMed Central

    de Beurs, Derek

    2017-01-01

    Although suicide is a major public health issue worldwide, we understand little of the onset and development of suicidal behaviour. Suicidal behaviour is argued to be the end result of the complex interaction between psychological, social and biological factors. Epidemiological studies resulted in a range of risk factors for suicidal behaviour, but we do not yet understand how their interaction increases the risk for suicidal behaviour. A new approach called network analysis can help us better understand this process as it allows us to visualize and quantify the complex association between many different symptoms or risk factors. A network analysis of data containing information on suicidal patients can help us understand how risk factors interact and how their interaction is related to suicidal thoughts and behaviour. A network perspective has been successfully applied to the field of depression and psychosis, but not yet to the field of suicidology. In this theoretical article, I will introduce the concept of network analysis to the field of suicide prevention, and offer directions for future applications and studies.

  5. A validation of the construct and reliability of an emotional intelligence scale applied to nursing students1

    PubMed Central

    Espinoza-Venegas, Maritza; Sanhueza-Alvarado, Olivia; Ramírez-Elizondo, Noé; Sáez-Carrillo, Katia

    2015-01-01

    OBJECTIVE: The current study aimed to validate the construct and reliability of an emotional intelligence scale. METHOD: The Trait Meta-Mood Scale-24 was applied to 349 nursing students. The process included content validation, which involved expert reviews, pilot testing, measurements of reliability using Cronbach's alpha, and factor analysis to corroborate the validity of the theoretical model's construct. RESULTS: Adequate Cronbach coefficients were obtained for all three dimensions, and factor analysis confirmed the scale's dimensions (perception, comprehension, and regulation). CONCLUSION: The Trait Meta-Mood Scale is a reliable and valid tool to measure the emotional intelligence of nursing students. Its use allows for accurate determinations of individuals' abilities to interpret and manage emotions. At the same time, this new construct is of potential importance for measurements in nursing leadership; educational, organizational, and personal improvements; and the establishment of effective relationships with patients. PMID:25806642

  6. The Effects of Describing Antecedent Stimuli and Performance Criteria in Task Analysis Instruction for Graphing

    ERIC Educational Resources Information Center

    Tyner, Bryan C.; Fienup, Daniel M.

    2016-01-01

    Task analyses are ubiquitous to applied behavior analysis interventions, yet little is known about the factors that make them effective. Numerous task analyses have been published in behavior analytic journals for constructing single-subject design graphs; however, learner outcomes using these task analyses may fall short of what could be…

  7. Numerical analysis of helical dielectric elastomer actuator

    NASA Astrophysics Data System (ADS)

    Park, Jang Ho; Nair, Saurabh; Kim, Daewon

    2017-04-01

    Dielectric elastomer actuators (DEA) are known for its capability of experiencing extreme strains, as it can expand and contract based on specific actuation voltage applied. On contrary, helical DEA (HDEA) with its unique configuration does not only provide the contractile and extendable capabilities, but also can aid in attaining results for bending and torsion. The concept of HDEA embraces many new techniques and can be applied in multiple disciplines. Thus, this paper focuses on the simulation of HDEA with helical compliant electrodes that is a major factor prior to its application. The attributes of the material used to build the structure plays a vital role in the behavior of the system. For numerical analysis of HDEA, the material characteristics are input into a commercial grade software, and then the appropriate analysis is performed to retrieve its outcome. Applying the material characteristics into numerical analysis modeling, the functionality of HDEA for various activations can be achieved, which is used to test and comply with the fabricated final product.

  8. Psychometric Evaluation of the Overexcitability Questionnaire-Two Applying Bayesian Structural Equation Modeling (BSEM) and Multiple-Group BSEM-Based Alignment with Approximate Measurement Invariance

    PubMed Central

    De Bondt, Niki; Van Petegem, Peter

    2015-01-01

    The Overexcitability Questionnaire-Two (OEQ-II) measures the degree and nature of overexcitability, which assists in determining the developmental potential of an individual according to Dabrowski's Theory of Positive Disintegration. Previous validation studies using frequentist confirmatory factor analysis, which postulates exact parameter constraints, led to model rejection and a long series of model modifications. Bayesian structural equation modeling (BSEM) allows the application of zero-mean, small-variance priors for cross-loadings, residual covariances, and differences in measurement parameters across groups, better reflecting substantive theory and leading to better model fit and less overestimation of factor correlations. Our BSEM analysis with a sample of 516 students in higher education yields positive results regarding the factorial validity of the OEQ-II. Likewise, applying BSEM-based alignment with approximate measurement invariance, the absence of non-invariant factor loadings and intercepts across gender is supportive of the psychometric quality of the OEQ-II. Compared to males, females scored significantly higher on emotional and sensual overexcitability, and significantly lower on psychomotor overexcitability. PMID:26733931

  9. Psychometric Evaluation of the Overexcitability Questionnaire-Two Applying Bayesian Structural Equation Modeling (BSEM) and Multiple-Group BSEM-Based Alignment with Approximate Measurement Invariance.

    PubMed

    De Bondt, Niki; Van Petegem, Peter

    2015-01-01

    The Overexcitability Questionnaire-Two (OEQ-II) measures the degree and nature of overexcitability, which assists in determining the developmental potential of an individual according to Dabrowski's Theory of Positive Disintegration. Previous validation studies using frequentist confirmatory factor analysis, which postulates exact parameter constraints, led to model rejection and a long series of model modifications. Bayesian structural equation modeling (BSEM) allows the application of zero-mean, small-variance priors for cross-loadings, residual covariances, and differences in measurement parameters across groups, better reflecting substantive theory and leading to better model fit and less overestimation of factor correlations. Our BSEM analysis with a sample of 516 students in higher education yields positive results regarding the factorial validity of the OEQ-II. Likewise, applying BSEM-based alignment with approximate measurement invariance, the absence of non-invariant factor loadings and intercepts across gender is supportive of the psychometric quality of the OEQ-II. Compared to males, females scored significantly higher on emotional and sensual overexcitability, and significantly lower on psychomotor overexcitability.

  10. Factor structure and psychometric properties of the Fertility Problem Inventory–Short Form

    PubMed Central

    Zurlo, Maria Clelia; Cattaneo Della Volta, Maria Franscesca; Vallone, Federica

    2017-01-01

    The study analyses factor structure and psychometric properties of the Italian version of the Fertility Problem Inventory–Short Form. A sample of 206 infertile couples completed the Italian version of Fertility Problem Inventory (46 items) with demographics, State Anxiety Scale of State-Trait Anxiety Inventory (Form Y), Edinburgh Depression Scale and Dyadic Adjustment Scale, used to assess convergent and discriminant validity. Confirmatory factor analysis was unsatisfactory (comparative fit index = 0.87; Tucker-Lewis Index = 0.83; root mean square error of approximation = 0.17), and Cronbach’s α (0.95) revealed a redundancy of items. Exploratory factor analysis was carried out deleting cross-loading items, and Mokken scale analysis was applied to verify the items homogeneity within the reduced subscales of the questionnaire. The Fertility Problem Inventory–Short Form consists of 27 items, tapping four meaningful and reliable factors. Convergent and discriminant validity were confirmed. Findings indicated that the Fertility Problem Inventory–Short Form is a valid and reliable measure to assess infertility-related stress dimensions. PMID:29379625

  11. Effective Factors in Providing Holistic Care: A Qualitative Study

    PubMed Central

    Zamanzadeh, Vahid; Jasemi, Madineh; Valizadeh, Leila; Keogh, Brian; Taleghani, Fariba

    2015-01-01

    Background: Holistic care is a comprehensive model of caring. Previous studies have shown that most nurses do not apply this method. Examining the effective factors in nurses’ provision of holistic care can help with enhancing it. Studying these factors from the point of view of nurses will generate real and meaningful concepts and can help to extend this method of caring. Materials and Methods: A qualitative study was used to identify effective factors in holistic care provision. Data gathered by interviewing 14 nurses from university hospitals in Iran were analyzed with a conventional qualitative content analysis method and by using MAXQDA (professional software for qualitative and mixed methods data analysis) software. Results: Analysis of data revealed three main themes as effective factors in providing holistic care: The structure of educational system, professional environment, and personality traits. Conclusion: Establishing appropriate educational, management systems, and promoting religiousness and encouragement will induce nurses to provide holistic care and ultimately improve the quality of their caring. PMID:26009677

  12. Comparative study on the selectivity of various spectrophotometric techniques for the determination of binary mixture of fenbendazole and rafoxanide.

    PubMed

    Saad, Ahmed S; Attia, Ali K; Alaraki, Manal S; Elzanfaly, Eman S

    2015-11-05

    Five different spectrophotometric methods were applied for simultaneous determination of fenbendazole and rafoxanide in their binary mixture; namely first derivative, derivative ratio, ratio difference, dual wavelength and H-point standard addition spectrophotometric methods. Different factors affecting each of the applied spectrophotometric methods were studied and the selectivity of the applied methods was compared. The applied methods were validated as per the ICH guidelines and good accuracy; specificity and precision were proven within the concentration range of 5-50 μg/mL for both drugs. Statistical analysis using one-way ANOVA proved no significant differences among the proposed methods for the determination of the two drugs. The proposed methods successfully determined both drugs in laboratory prepared and commercially available binary mixtures, and were found applicable for the routine analysis in quality control laboratories. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Factors affecting construction performance: exploratory factor analysis

    NASA Astrophysics Data System (ADS)

    Soewin, E.; Chinda, T.

    2018-04-01

    The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

  14. Analysis on Influence Factors of Adaptive Filter Acting on ANC

    NASA Astrophysics Data System (ADS)

    Zhang, Xiuqun; Zou, Liang; Ni, Guangkui; Wang, Xiaojun; Han, Tao; Zhao, Quanfu

    The noise problem has become more and more serious in recent years. The adaptive filter theory which is applied in ANC [1] (active noise control) has also attracted more and more attention. In this article, the basic principle and algorithm of adaptive theory are both researched. And then the influence factor that affects its covergence rate and noise reduction is also simulated.

  15. 29 CFR 1608.11 - Limitations on the application of these guidelines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... do not apply to, and the section 713(b)(1) defense is not available for the purpose of, determining... such factors as progress in correcting the conditions disclosed by the self analysis. The currency of...

  16. 29 CFR 1608.11 - Limitations on the application of these guidelines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... do not apply to, and the section 713(b)(1) defense is not available for the purpose of, determining... such factors as progress in correcting the conditions disclosed by the self analysis. The currency of...

  17. 29 CFR 1608.11 - Limitations on the application of these guidelines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... do not apply to, and the section 713(b)(1) defense is not available for the purpose of, determining... such factors as progress in correcting the conditions disclosed by the self analysis. The currency of...

  18. Application of commercial aircraft accident investigation techniques to a railroad derailment.

    DOT National Transportation Integrated Search

    1973-01-01

    Crash investigation techniques utilized by human factors teams in investigating commercial airline crashes have been applied in the analysis of a railroad train derailment - crash. Passengers in cars that remained upright experienced very low deceler...

  19. [The impact of public health system on mortality of malignant neoplasms in Voronezh oblast].

    PubMed

    Chesnokov, P E; Kuralesina, E N

    2013-01-01

    The total mortality and population mortality of main classes of diseases and single causes of death are to be considered in operative and strategic planning of development of national economy and industry In the Russian Federation, the decrease of mortality of neoplasms including malignant ones up to 190 per 100 000 of population in 2020 will be one of indicators of effectiveness of implementation of the State program of development of public health in the Russian Federation. The study was organized to determine the possibility to impact the level and dynamics of mortality of malignant neoplasms by means of variation of managed factors on the basis of indicators of activity of public health system. The main indicators of population health and activity of health institutions of Voronezh oblast were analyzed. The methods of mathematical statistics, management theory, system analysis and mathematical modeling were applied. To study the impact of managed factors on mortality of malignant neoplasms on the territory of Voronezh oblast the analysis of correlation interdependency was applied concerning 162 factors characterizing condition and activity of public health system according oblast districts and level of mortality of malignant neoplasms among adult population. The combinations of factors were calculated using the model to determine the level of prospective mortality to come in certain time after implementation of activities changing the given levels of factors. The data concerning qualitative interrelationship of indicators of condition and functioning of network of health institutions with indicators of level and dynamics of mortality of malignant neoplasms can be applied to model and forecast and to evaluate the current and forthcoming situation according indicators of mentioned mortality on the territory of Voronezh oblast in development of comprehensive plan of activities targeted to decreasing of this indicator.

  20. Factors Influencing Internal Medicine Resident Choice of Infectious Diseases or Other Specialties: A National Cross-sectional Study

    PubMed Central

    Bonura, Erin M.; Lee, Eun Sul; Ramsey, Katrina; Armstrong, Wendy S.

    2016-01-01

    Background. Only 49% of infectious diseases (ID) fellowship programs were filled in 2015 through the national match, but little is known about internal medicine (IM) resident perceptions of ID and factors related to IM resident career choice. Methods. We conducted 25 interviews and disseminated a Web-based survey to graduating IM residents in the United States utilizing a 2-stage sampling strategy. Participants were categorized into 3 groups based on interest in ID: (1) applied/intended to apply to ID; (2) interested in ID but did not apply; (3) never interested in ID. We conducted all analysis using poststratification adjustment weights with survey data analysis procedures. Results. Of the 590 participants, 42 (7%) selected category 1, 188 (32%) category 2, and 360 (61%) category 3. Most (65%) developed an interest in their ultimate career before residency. Of those interested in ID, >52% rated their ID medical school curriculum as very good and influential on their interest in ID. Ninety-one percent of category 2 participants felt mentorship was influential on career choice, although 43% identified an ID mentor. Category 2 chose salary as the most dissuading factor and the most likely intervention to increase ID interest. Conclusions. In this nationally representative sample of graduating IM residents, most develop an interest in their ultimate career before residency. Factors influencing this decision reside in both medical school and residency, which is consistent with career decision-making constructs. By identifying career determining factors and understanding how they fit into medical training frameworks, we can develop targeted initiatives to reinvigorate interest in ID. PMID:27126345

  1. Factors Influencing Internal Medicine Resident Choice of Infectious Diseases or Other Specialties: A National Cross-sectional Study.

    PubMed

    Bonura, Erin M; Lee, Eun Sul; Ramsey, Katrina; Armstrong, Wendy S

    2016-07-15

    Only 49% of infectious diseases (ID) fellowship programs were filled in 2015 through the national match, but little is known about internal medicine (IM) resident perceptions of ID and factors related to IM resident career choice. We conducted 25 interviews and disseminated a Web-based survey to graduating IM residents in the United States utilizing a 2-stage sampling strategy. Participants were categorized into 3 groups based on interest in ID: (1) applied/intended to apply to ID; (2) interested in ID but did not apply; (3) never interested in ID. We conducted all analysis using poststratification adjustment weights with survey data analysis procedures. Of the 590 participants, 42 (7%) selected category 1, 188 (32%) category 2, and 360 (61%) category 3. Most (65%) developed an interest in their ultimate career before residency. Of those interested in ID, >52% rated their ID medical school curriculum as very good and influential on their interest in ID. Ninety-one percent of category 2 participants felt mentorship was influential on career choice, although 43% identified an ID mentor. Category 2 chose salary as the most dissuading factor and the most likely intervention to increase ID interest. In this nationally representative sample of graduating IM residents, most develop an interest in their ultimate career before residency. Factors influencing this decision reside in both medical school and residency, which is consistent with career decision-making constructs. By identifying career determining factors and understanding how they fit into medical training frameworks, we can develop targeted initiatives to reinvigorate interest in ID. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  2. The integration of Human Factors (HF) in the SAR process training course text

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

    Ryan, T.G.

    1995-03-01

    This text provides the technical basis for a two-day course on human factors (HF), as applied to the Safety Analysis Report (SAR) process. The overall objective of this text and course is to: provide the participant with a working knowledge of human factors-related requirements, suggestions for doing a human safety analysis applying a graded approach, and an ability to demonstrate using the results of the human safety analysis, that human factors elements as defined by DOE (human factors engineering, procedures, training, oversight, staffing, qualifications), can support wherever necessary, nuclear safety commitments in the SAR. More specifically, the objectives of themore » text and course are: (1) To provide the SAR preparer with general guidelines for doing HE within the context of a graded approach for the SAR; (2) To sensitize DOE facility managers and staff, safety analysts and SAR preparers, independent reviewers, and DOE reviewers and regulators, to DOE Order 5480.23 requirements for HE in the SAR; (3) To provide managers, analysts, reviewers and regulators with a working knowledge of HE concepts and techniques within the context of a graded approach for the SAR, and (4) To provide SAR managers and DOE reviewers and regulators with general guidelines for monitoring and coordinating the work of preparers of HE inputs throughout the SAR process, and for making decisions regarding the safety relevance of HE inputs to the SAR. As a ready reference for implementing the human factors requirements of DOE Order 5480.22 and DOE Standard 3009-94, this course text and accompanying two-day course are intended for all persons who are involved in the SAR.« less

  3. Development and validation of the stigma scale for epilepsy in Turkey.

    PubMed

    Baybaş, Sevim; Yıldırım, Zerrin; Ertem, Devrimsel Harika; Dirican, Ayten; Dirican, Ahmet

    2017-02-01

    Epilepsy is a chronic disease with an increased risk of stigma. The aim of this study was to investigate the efficacy of a scale developed by the authors to determine the level of stigma in Turkish patients with epilepsy and their relatives. In this pilot study, two scales were developed, one consisting of 32 questions for the patients and one of 20 questions for the patients' relatives. Initially, a total of 30 patients with epilepsy and 30 relatives of the patients were included. The Cronbach's alpha coefficient was calculated in a reliability analysis of validity applying the scales to 302 patients and 201 relatives of the patients. The Pearson correlation coefficient was used for the reliability analysis of the test-retest. The t-test was used in paired series, and factor analysis was conducted. The correlation between the clinical and demographical data and the stigma scores was evaluated. The scales were applied to participants twice under the same conditions in one-week interval. In the test-retest analysis, the internal consistency of the scales was high and reliable. In the analysis of the patients, the Cronbach's alpha value of the scale was found to be 0.915. In the factor analysis, the questions were grouped into five factors including social isolation, discrimination, insufficiency, false beliefs, and stigma resistance. The factors with the highest contribution to the stigma level were social isolation and discrimination. In the stigma scores, a significant correlation was found between the age of the patient, frequency of seizures, education status, level of income, and the amount of antiepileptic drugs used. In the analysis of the patients' relatives, the Cronbach's alpha value of the scale was found to be 0.892. In the factor analysis, the questions were classified as discrimination, prejudgments, and false beliefs. The factor which most contributed to the stigma level was discrimination. A significant correlation was found in the stigma scores between sex, education status, marital status, and income distribution. According to our study results, it is clearly seen that both patients and their relatives suffer from epilepsy-associated stigma. Patients with epilepsy and their relatives are faced with discrimination in society, resulting in social isolation. We, therefore, believe that both patients and their relatives should be informed in detail about discrimination to overcome this challenge. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Principal component analysis of normalized full spectrum mass spectrometry data in multiMS-toolbox: An effective tool to identify important factors for classification of different metabolic patterns and bacterial strains.

    PubMed

    Cejnar, Pavel; Kuckova, Stepanka; Prochazka, Ales; Karamonova, Ludmila; Svobodova, Barbora

    2018-06-15

    Explorative statistical analysis of mass spectrometry data is still a time-consuming step. We analyzed critical factors for application of principal component analysis (PCA) in mass spectrometry and focused on two whole spectrum based normalization techniques and their application in the analysis of registered peak data and, in comparison, in full spectrum data analysis. We used this technique to identify different metabolic patterns in the bacterial culture of Cronobacter sakazakii, an important foodborne pathogen. Two software utilities, the ms-alone, a python-based utility for mass spectrometry data preprocessing and peak extraction, and the multiMS-toolbox, an R software tool for advanced peak registration and detailed explorative statistical analysis, were implemented. The bacterial culture of Cronobacter sakazakii was cultivated on Enterobacter sakazakii Isolation Agar, Blood Agar Base and Tryptone Soya Agar for 24 h and 48 h and applied by the smear method on an Autoflex speed MALDI-TOF mass spectrometer. For three tested cultivation media only two different metabolic patterns of Cronobacter sakazakii were identified using PCA applied on data normalized by two different normalization techniques. Results from matched peak data and subsequent detailed full spectrum analysis identified only two different metabolic patterns - a cultivation on Enterobacter sakazakii Isolation Agar showed significant differences to the cultivation on the other two tested media. The metabolic patterns for all tested cultivation media also proved the dependence on cultivation time. Both whole spectrum based normalization techniques together with the full spectrum PCA allow identification of important discriminative factors in experiments with several variable condition factors avoiding any problems with improper identification of peaks or emphasis on bellow threshold peak data. The amounts of processed data remain still manageable. Both implemented software utilities are available free of charge from http://uprt.vscht.cz/ms. Copyright © 2018 John Wiley & Sons, Ltd.

  5. Impact of interpatient variability on organ dose estimates according to MIRD schema: Uncertainty and variance-based sensitivity analysis.

    PubMed

    Zvereva, Alexandra; Kamp, Florian; Schlattl, Helmut; Zankl, Maria; Parodi, Katia

    2018-05-17

    Variance-based sensitivity analysis (SA) is described and applied to the radiation dosimetry model proposed by the Committee on Medical Internal Radiation Dose (MIRD) for the organ-level absorbed dose calculations in nuclear medicine. The uncertainties in the dose coefficients thus calculated are also evaluated. A Monte Carlo approach was used to compute first-order and total-effect SA indices, which rank the input factors according to their influence on the uncertainty in the output organ doses. These methods were applied to the radiopharmaceutical (S)-4-(3- 18 F-fluoropropyl)-L-glutamic acid ( 18 F-FSPG) as an example. Since 18 F-FSPG has 11 notable source regions, a 22-dimensional model was considered here, where 11 input factors are the time-integrated activity coefficients (TIACs) in the source regions and 11 input factors correspond to the sets of the specific absorbed fractions (SAFs) employed in the dose calculation. The SA was restricted to the foregoing 22 input factors. The distributions of the input factors were built based on TIACs of five individuals to whom the radiopharmaceutical 18 F-FSPG was administered and six anatomical models, representing two reference, two overweight, and two slim individuals. The self-absorption SAFs were mass-scaled to correspond to the reference organ masses. The estimated relative uncertainties were in the range 10%-30%, with a minimum and a maximum for absorbed dose coefficients for urinary bladder wall and heart wall, respectively. The applied global variance-based SA enabled us to identify the input factors that have the highest influence on the uncertainty in the organ doses. With the applied mass-scaling of the self-absorption SAFs, these factors included the TIACs for absorbed dose coefficients in the source regions and the SAFs from blood as source region for absorbed dose coefficients in highly vascularized target regions. For some combinations of proximal target and source regions, the corresponding cross-fire SAFs were found to have an impact. Global variance-based SA has been for the first time applied to the MIRD schema for internal dose calculation. Our findings suggest that uncertainties in computed organ doses can be substantially reduced by performing an accurate determination of TIACs in the source regions, accompanied by the estimation of individual source region masses along with the usage of an appropriate blood distribution in a patient's body and, in a few cases, the cross-fire SAFs from proximal source regions. © 2018 American Association of Physicists in Medicine.

  6. Confirmatory factor analysis of the Malay version comprehensive feeding practices questionnaire tested among mothers of primary school children in Malaysia.

    PubMed

    Shohaimi, Shamarina; Wei, Wong Yoke; Shariff, Zalilah Mohd

    2014-01-01

    Comprehensive feeding practices questionnaire (CFPQ) is an instrument specifically developed to evaluate parental feeding practices. It has been confirmed among children in America and applied to populations in France, Norway, and New Zealand. In order to extend the application of CFPQ, we conducted a factor structure validation of the translated version of CFPQ (CFPQ-M) using confirmatory factor analysis among mothers of primary school children (N = 397) in Malaysia. Several items were modified for cultural adaptation. Of 49 items, 39 items with loading factors >0.40 were retained in the final model. The confirmatory factor analysis revealed that the final model (twelve-factor model with 39 items and 2 error covariances) displayed the best fit for our sample (Chi-square = 1147; df = 634; P < 0.05; CFI = 0.900; RMSEA = 0.045; SRMR = 0.0058). The instrument with some modifications was confirmed among mothers of school children in Malaysia. The present study extends the usability of the CFPQ and enables researchers and parents to better understand the relationships between parental feeding practices and related problems such as childhood obesity.

  7. Methodological Synthesis in Quantitative L2 Research: A Review of Reviews and a Case Study of Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Plonsky, Luke; Gonulal, Talip

    2015-01-01

    Research synthesis and meta-analysis provide a pathway to bring together findings in a given domain with greater systematicity, objectivity, and transparency than traditional reviews. The same techniques and corresponding benefits can be and have been applied to examine methodological practices in second language (L2) research (e.g., Plonsky,…

  8. Peer Bullying among High School Students: Turkish Version of Bullying Scale

    ERIC Educational Resources Information Center

    Arslan, Nihan

    2017-01-01

    The aim of study was to conduct the reliability and validity studies of the Turkish version of The Forms of Bullying Scale (FBS; Shaw at el., 2013). The Turkish form of the scale was applied on 357 high school students. Scale was examined by the reliability analysis and confirmatory factor analysis within the scope of the adaptation study.…

  9. Modelling and analysis of FMS productivity variables by ISM, SEM and GTMA approach

    NASA Astrophysics Data System (ADS)

    Jain, Vineet; Raj, Tilak

    2014-09-01

    Productivity has often been cited as a key factor in a flexible manufacturing system (FMS) performance, and actions to increase it are said to improve profitability and the wage earning capacity of employees. Improving productivity is seen as a key issue for survival and success in the long term of a manufacturing system. The purpose of this paper is to make a model and analysis of the productivity variables of FMS. This study was performed by different approaches viz. interpretive structural modelling (ISM), structural equation modelling (SEM), graph theory and matrix approach (GTMA) and a cross-sectional survey within manufacturing firms in India. ISM has been used to develop a model of productivity variables, and then it has been analyzed. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) are powerful statistical techniques. CFA is carried by SEM. EFA is applied to extract the factors in FMS by the statistical package for social sciences (SPSS 20) software and confirming these factors by CFA through analysis of moment structures (AMOS 20) software. The twenty productivity variables are identified through literature and four factors extracted, which involves the productivity of FMS. The four factors are people, quality, machine and flexibility. SEM using AMOS 20 was used to perform the first order four-factor structures. GTMA is a multiple attribute decision making (MADM) methodology used to find intensity/quantification of productivity variables in an organization. The FMS productivity index has purposed to intensify the factors which affect FMS.

  10. A combined approach based on MAF analysis and AHP method to fault detection mapping: A case study from a gas field, southwest of Iran

    NASA Astrophysics Data System (ADS)

    Shakiba, Sima; Asghari, Omid; Khah, Nasser Keshavarz Faraj

    2018-01-01

    A combined geostatitical methodology based on Min/Max Auto-correlation Factor (MAF) analysis and Analytical Hierarchy Process (AHP) is presented to generate a suitable Fault Detection Map (FDM) through seismic attributes. Five seismic attributes derived from a 2D time slice obtained from data related to a gas field located in southwest of Iran are used including instantaneous amplitude, similarity, energy, frequency, and Fault Enhancement Filter (FEF). The MAF analysis is implemented to reduce dimension of input variables, and then AHP method is applied on three obtained de-correlated MAF factors as evidential layer. Three Decision Makers (DMs) are used to construct PCMs for determining weights of selected evidential layer. Finally, weights obtained by AHP were multiplied in normalized valued of each alternative (MAF layers) and the concluded weighted layers were integrated in order to prepare final FDM. Results proved that applying algorithm proposed in this study generate a map more acceptable than the each individual attribute and sharpen the non-surface discontinuities as well as enhancing continuity of detected faults.

  11. Biomechanical factors associated with mandibular cantilevers: analysis with three-dimensional finite element models.

    PubMed

    Gonda, Tomoya; Yasuda, Daiisa; Ikebe, Kazunori; Maeda, Yoshinobu

    2014-01-01

    Although the risks of using a cantilever to treat missing teeth have been described, the mechanisms remain unclear. This study aimed to reveal these mechanisms from a biomechanical perspective. The effects of various implant sites, number of implants, and superstructural connections on stress distribution in the marginal bone were analyzed with three-dimensional finite element models based on mandibular computed tomography data. Forces from the masseter, temporalis, and internal pterygoid were applied as vectors. Two three-dimensional finite element models were created with the edentulous mandible showing severe and relatively modest residual ridge resorption. Cantilevers of the premolar and molar were simulated in the superstructures in the models. The following conditions were also included as factors in the models to investigate changes: poor bone quality, shortened dental arch, posterior occlusion, lateral occlusion, double force of the masseter, and short implant. Multiple linear regression analysis with a forced-entry method was performed with stress values as the objective variable and the factors as the explanatory variable. When bone mass was high, stress around the implant caused by differences in implantation sites was reduced. When bone mass was low, the presence of a cantilever was a possible risk factor. The stress around the implant increased significantly if bone quality was poor or if increased force (eg, bruxism) was applied. The addition of a cantilever to the superstructure increased stress around implants. When large muscle forces were applied to a superstructure with cantilevers or if bone quality was poor, stress around the implants increased.

  12. Applying a coping with stress questionnaire for cancer patients to patients with non-cancer chronic illnesses.

    PubMed

    Orive, Miren; Quintana, Jose M; Vrotsou, Kalliopi; Las Hayas, Carlota; Bilbao, Amaia; Barrio, Irantzu; Matellanes, Begoña; Padierna, Jesús A

    2013-06-01

    One of the few instruments to evaluate coping skills among patients with chronic illnesses is the Cuestionario de Afrontamiento al Estrés para Pacientes Oncológicos (CAEPO), created initially for cancer patients. We evaluate how well CAEPO applies to patients with non-cancer chronic illnesses. A total of 344 patients (115 with chronic hepatitis C, 120 with inflammatory bowel disease and 109 with recurrent vertigo) completed the CAEPO. Exploratory factor analysis and Cronbach's alpha provide only partial support for the seven factors suggested by the original CAEPO. A streamlined version with fewer dimensions and items may be a better solution for identifying coping strategies among these patients.

  13. Characterization of Residual Stress Effects on Fatigue Crack Growth of a Friction Stir Welded Aluminum Alloy

    NASA Technical Reports Server (NTRS)

    Newman, John A.; Smith, Stephen W.; Seshadri, Banavara R.; James, Mark A.; Brazill, Richard L.; Schultz, Robert W.; Donald, J. Keith; Blair, Amy

    2015-01-01

    An on-line compliance-based method to account for residual stress effects in stress-intensity factor and fatigue crack growth property determinations has been evaluated. Residual stress intensity factor results determined from specimens containing friction stir weld induced residual stresses are presented, and the on-line method results were found to be in excellent agreement with residual stress-intensity factor data obtained using the cut compliance method. Variable stress-intensity factor tests were designed to demonstrate that a simple superposition model, summing the applied stress-intensity factor with the residual stress-intensity factor, can be used to determine the total crack-tip stress-intensity factor. Finite element, VCCT (virtual crack closure technique), and J-integral analysis methods have been used to characterize weld-induced residual stress using thermal expansion/contraction in the form of an equivalent delta T (change in local temperature during welding) to simulate the welding process. This equivalent delta T was established and applied to analyze different specimen configurations to predict residual stress distributions and associated residual stress-intensity factor values. The predictions were found to agree well with experimental results obtained using the crack- and cut-compliance methods.

  14. Understanding clinician attitudes towards implementation of guided self-help cognitive behaviour therapy for those who hear distressing voices: using factor analysis to test normalisation process theory.

    PubMed

    Hazell, Cassie M; Strauss, Clara; Hayward, Mark; Cavanagh, Kate

    2017-07-24

    The Normalisation Process Theory (NPT) has been used to understand the implementation of physical health care interventions. The current study aims to apply the NPT model to a secondary mental health context, and test the model using exploratory factor analysis. This study will consider the implementation of a brief cognitive behaviour therapy for psychosis (CBTp) intervention. Mental health clinicians were asked to complete a NPT-based questionnaire on the implementation of a brief CBTp intervention. All clinicians had experience of either working with the target client group or were able to deliver psychological therapies. In total, 201 clinicians completed the questionnaire. The results of the exploratory factor analysis found partial support for the NPT model, as three of the NPT factors were extracted: (1) coherence, (2) cognitive participation, and (3) reflexive monitoring. We did not find support for the fourth NPT factor (collective action). All scales showed strong internal consistency. Secondary analysis of these factors showed clinicians to generally support the implementation of the brief CBTp intervention. This study provides strong evidence for the validity of the three NPT factors extracted. Further research is needed to determine whether participants' level of seniority moderates factor extraction, whether this factor structure can be generalised to other healthcare settings, and whether pre-implementation attitudes predict actual implementation outcomes.

  15. Applications of stable isotope analysis in mammalian ecology.

    PubMed

    Walter, W David; Kurle, Carolyn M; Hopkins, John B

    2014-01-01

    In this editorial, we provide a brief introduction and summarize the 10 research articles included in this Special Issue on Applications of stable isotope analysis in mammalian ecology. The first three articles report correction and discrimination factors that can be used to more accurately estimate the diets of extinct and extant mammals using stable isotope analysis. The remaining seven applied research articles use stable isotope analysis to address a variety of wildlife conservation and management questions from the oceans to the mountains.

  16. Application of radioisotope XRF and thermoluminescence (TL) dating in investigation of pottery from Tell AL-Kasra archaeological site, Syria.

    PubMed

    Abboud, R; Issa, H; Abed-Allah, Y D; Bakraji, E H

    2015-11-01

    Statistical analysis based on chemical composition, using radioisotope X-ray fluorescence, have been applied on 39 ancient pottery fragments coming from the excavation at Tell Al-Kasra archaeological site, Syria. Three groups were defined by applying Cluster and Factor analysis statistical methods. Thermoluminescence (TL) dating was investigated on three sherds taken from the bathroom (hammam) on the site. Multiple aliquot additive dose (MAAD) was used to estimate the paleodose value, and the gamma spectrometry was used to estimate the dose rate. The average age was found to be 715±36 year. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Integrative Analysis of Transcription Factor Combinatorial Interactions Using a Bayesian Tensor Factorization Approach

    PubMed Central

    Ye, Yusen; Gao, Lin; Zhang, Shihua

    2017-01-01

    Transcription factors play a key role in transcriptional regulation of genes and determination of cellular identity through combinatorial interactions. However, current studies about combinatorial regulation is deficient due to lack of experimental data in the same cellular environment and extensive existence of data noise. Here, we adopt a Bayesian CANDECOMP/PARAFAC (CP) factorization approach (BCPF) to integrate multiple datasets in a network paradigm for determining precise TF interaction landscapes. In our first application, we apply BCPF to integrate three networks built based on diverse datasets of multiple cell lines from ENCODE respectively to predict a global and precise TF interaction network. This network gives 38 novel TF interactions with distinct biological functions. In our second application, we apply BCPF to seven types of cell type TF regulatory networks and predict seven cell lineage TF interaction networks, respectively. By further exploring the dynamics and modularity of them, we find cell lineage-specific hub TFs participate in cell type or lineage-specific regulation by interacting with non-specific TFs. Furthermore, we illustrate the biological function of hub TFs by taking those of cancer lineage and blood lineage as examples. Taken together, our integrative analysis can reveal more precise and extensive description about human TF combinatorial interactions. PMID:29033978

  18. Integrative Analysis of Transcription Factor Combinatorial Interactions Using a Bayesian Tensor Factorization Approach.

    PubMed

    Ye, Yusen; Gao, Lin; Zhang, Shihua

    2017-01-01

    Transcription factors play a key role in transcriptional regulation of genes and determination of cellular identity through combinatorial interactions. However, current studies about combinatorial regulation is deficient due to lack of experimental data in the same cellular environment and extensive existence of data noise. Here, we adopt a Bayesian CANDECOMP/PARAFAC (CP) factorization approach (BCPF) to integrate multiple datasets in a network paradigm for determining precise TF interaction landscapes. In our first application, we apply BCPF to integrate three networks built based on diverse datasets of multiple cell lines from ENCODE respectively to predict a global and precise TF interaction network. This network gives 38 novel TF interactions with distinct biological functions. In our second application, we apply BCPF to seven types of cell type TF regulatory networks and predict seven cell lineage TF interaction networks, respectively. By further exploring the dynamics and modularity of them, we find cell lineage-specific hub TFs participate in cell type or lineage-specific regulation by interacting with non-specific TFs. Furthermore, we illustrate the biological function of hub TFs by taking those of cancer lineage and blood lineage as examples. Taken together, our integrative analysis can reveal more precise and extensive description about human TF combinatorial interactions.

  19. A sequential factorial analysis approach to characterize the effects of uncertainties for supporting air quality management

    NASA Astrophysics Data System (ADS)

    Wang, S.; Huang, G. H.; Veawab, A.

    2013-03-01

    This study proposes a sequential factorial analysis (SFA) approach for supporting regional air quality management under uncertainty. SFA is capable not only of examining the interactive effects of input parameters, but also of analyzing the effects of constraints. When there are too many factors involved in practical applications, SFA has the advantage of conducting a sequence of factorial analyses for characterizing the effects of factors in a systematic manner. The factor-screening strategy employed in SFA is effective in greatly reducing the computational effort. The proposed SFA approach is applied to a regional air quality management problem for demonstrating its applicability. The results indicate that the effects of factors are evaluated quantitatively, which can help decision makers identify the key factors that have significant influence on system performance and explore the valuable information that may be veiled beneath their interrelationships.

  20. Experienced quality factors: qualitative evaluation approach to audiovisual quality

    NASA Astrophysics Data System (ADS)

    Jumisko-Pyykkö, Satu; Häkkinen, Jukka; Nyman, Göte

    2007-02-01

    Subjective evaluation is used to identify impairment factors of multimedia quality. The final quality is often formulated via quantitative experiments, but this approach has its constraints, as subject's quality interpretations, experiences and quality evaluation criteria are disregarded. To identify these quality evaluation factors, this study examined qualitatively the criteria participants used to evaluate audiovisual video quality. A semi-structured interview was conducted with 60 participants after a subjective audiovisual quality evaluation experiment. The assessment compared several, relatively low audio-video bitrate ratios with five different television contents on mobile device. In the analysis, methodological triangulation (grounded theory, Bayesian networks and correspondence analysis) was applied to approach the qualitative quality. The results showed that the most important evaluation criteria were the factors of visual quality, contents, factors of audio quality, usefulness - followability and audiovisual interaction. Several relations between the quality factors and the similarities between the contents were identified. As a research methodological recommendation, the focus on content and usage related factors need to be further examined to improve the quality evaluation experiments.

  1. Topological data analysis (TDA) applied to reveal pedogenetic principles of European topsoil system.

    PubMed

    Savic, Aleksandar; Toth, Gergely; Duponchel, Ludovic

    2017-05-15

    Recent developments in applied mathematics are bringing new tools that are capable to synthesize knowledge in various disciplines, and help in finding hidden relationships between variables. One such technique is topological data analysis (TDA), a fusion of classical exploration techniques such as principal component analysis (PCA), and a topological point of view applied to clustering of results. Various phenomena have already received new interpretations thanks to TDA, from the proper choice of sport teams to cancer treatments. For the first time, this technique has been applied in soil science, to show the interaction between physical and chemical soil attributes and main soil-forming factors, such as climate and land use. The topsoil data set of the Land Use/Land Cover Area Frame survey (LUCAS) was used as a comprehensive database that consists of approximately 20,000 samples, each described by 12 physical and chemical parameters. After the application of TDA, results obtained were cross-checked against known grouping parameters including five types of land cover, nine types of climate and the organic carbon content of soil. Some of the grouping characteristics observed using standard approaches were confirmed by TDA (e.g., organic carbon content) but novel subtle relationships (e.g., magnitude of anthropogenic effect in soil formation), were discovered as well. The importance of this finding is that TDA is a unique mathematical technique capable of extracting complex relations hidden in soil science data sets, giving the opportunity to see the influence of physicochemical, biotic and abiotic factors on topsoil formation through fresh eyes. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. The wider determinants of inequalities in health: a decomposition analysis

    PubMed Central

    2011-01-01

    Background The common starting point of many studies scrutinizing the factors underlying health inequalities is that material, cultural-behavioural, and psycho-social factors affect the distribution of health systematically through income, education, occupation, wealth or similar indicators of socioeconomic structure. However, little is known regarding if and to what extent these factors can assert systematic influence on the distribution of health of a population independent of the effects channelled through income, education, or wealth. Methods Using representative data from the German Socioeconomic Panel, we apply Fields' regression based decomposition techniques to decompose variations in health into its sources. Controlling for income, education, occupation, and wealth, we assess the relative importance of the explanatory factors over and above their effect on the variation in health channelled through the commonly applied measures of socioeconomic status. Results The analysis suggests that three main factors persistently contribute to variance in health: the capability score, cultural-behavioural variables and to a lower extent, the materialist approach. Of the three, the capability score illustrates the explanatory power of interaction and compound effects as it captures the individual's socioeconomic, social, and psychological resources in relation to his/her exposure to life challenges. Conclusion Models that take a reductionist perspective and do not allow for the possibility that health inequalities are generated by factors over and above their effect on the variation in health channelled through one of the socioeconomic measures are underspecified and may fail to capture the determinants of health inequalities. PMID:21791075

  3. Evaluation of FTIR spectroscopy as diagnostic tool for colorectal cancer using spectral analysis

    NASA Astrophysics Data System (ADS)

    Dong, Liu; Sun, Xuejun; Chao, Zhang; Zhang, Shiyun; Zheng, Jianbao; Gurung, Rajendra; Du, Junkai; Shi, Jingsen; Xu, Yizhuang; Zhang, Yuanfu; Wu, Jinguang

    2014-03-01

    The aim of this study is to confirm FTIR spectroscopy as a diagnostic tool for colorectal cancer. 180 freshly removed colorectal samples were collected from 90 patients for spectrum analysis. The ratios of spectral intensity and relative intensity (/I1460) were calculated. Principal component analysis (PCA) and Fisher's discriminant analysis (FDA) were applied to distinguish the malignant from normal. The FTIR parameters of colorectal cancer and normal tissues were distinguished due to the contents or configurations of nucleic acids, proteins, lipids and carbohydrates. Related to nitrogen containing, water, protein and nucleic acid were increased significantly in the malignant group. Six parameters were selected as independent factors to perform discriminant functions. The sensitivity for FTIR in diagnosing colorectal cancer was 96.6% by discriminant analysis. Our study demonstrates that FTIR can be a useful technique for detection of colorectal cancer and may be applied in clinical colorectal cancer diagnosis.

  4. Predictive susceptibility analysis of typhoon induced landslides in Central Taiwan

    NASA Astrophysics Data System (ADS)

    Shou, Keh-Jian; Lin, Zora

    2017-04-01

    Climate change caused by global warming affects Taiwan significantly for the past decade. The increasing frequency of extreme rainfall events, in which concentrated and intensive rainfalls generally cause geohazards including landslides and debris flows. The extraordinary, such as 2004 Mindulle and 2009 Morakot, hit Taiwan and induced serious flooding and landslides. This study employs rainfall frequency analysis together with the atmospheric general circulation model (AGCM) downscaling estimation to understand the temporal rainfall trends, distributions, and intensities in the adopted Wu River watershed in Central Taiwan. To assess the spatial hazard of the landslides, landslide susceptibility analysis was also applied. Different types of rainfall factors were tested in the susceptibility models for a better accuracy. In addition, the routes of typhoons were also considered in the predictive analysis. The results of predictive analysis can be applied for risk prevention and management in the study area.

  5. Identifying the hydrochemical characteristics of rivers and groundwater by multivariate statistical analysis in the Sanjiang Plain, China

    NASA Astrophysics Data System (ADS)

    Cao, Yingjie; Tang, Changyuan; Song, Xianfang; Liu, Changming; Zhang, Yinghua

    2016-06-01

    Two multivariate statistical technologies, factor analysis (FA) and discriminant analysis (DA), are applied to study the river and groundwater hydrochemistry and its controlling processes in the Sanjiang Plain of the northeast China. Factor analysis identifies five factors which account for 79.65 % of the total variance in the dataset. Four factors bearing specific meanings as the river and groundwater hydrochemistry controlling processes are divided into two groups, the "natural hydrochemistry evolution" group and the "pollution" group. The "natural hydrochemistry evolution" group includes the salinity factor (factor 1) caused by rock weathering and the residence time factor (factor 2) reflecting the groundwater traveling time. The "pollution" group represents the groundwater quality deterioration due to geogenic pollution caused by elevated Fe and Mn (factor 3) and elevated nitrate (NO3 -) introduced by human activities such as agriculture exploitations (factor 5). The hydrochemical difference and hydraulic connection among rivers (surface water, SW), shallow groundwater (SG) and deep groundwater (DG) group are evaluated by the factor scores obtained from FA and DA (Fisher's method). It is showed that the river water is characterized as low salinity and slight pollution, and the shallow groundwater has the highest salinity and severe pollution. The SW is well separated from SG and DG by Fisher's discriminant function, but the SG and DG can not be well separated showing their hydrochemical similarities, and emphasize hydraulic connections between SG and DG.

  6. Benchmarking the efficiency of the Chilean water and sewerage companies: a double-bootstrap approach.

    PubMed

    Molinos-Senante, María; Donoso, Guillermo; Sala-Garrido, Ramon; Villegas, Andrés

    2018-03-01

    Benchmarking the efficiency of water companies is essential to set water tariffs and to promote their sustainability. In doing so, most of the previous studies have applied conventional data envelopment analysis (DEA) models. However, it is a deterministic method that does not allow to identify environmental factors influencing efficiency scores. To overcome this limitation, this paper evaluates the efficiency of a sample of Chilean water and sewerage companies applying a double-bootstrap DEA model. Results evidenced that the ranking of water and sewerage companies changes notably whether efficiency scores are computed applying conventional or double-bootstrap DEA models. Moreover, it was found that the percentage of non-revenue water and customer density are factors influencing the efficiency of Chilean water and sewerage companies. This paper illustrates the importance of using a robust and reliable method to increase the relevance of benchmarking tools.

  7. Theory versus practice in the human factors and ergonomics discipline: Trends in journal publications from 1960 to 2010.

    PubMed

    Chung, Amy Z Q; Williamson, Ann

    2018-01-01

    The research-practice gap has been highlighted as a barrier to effective practice in human factors and ergonomics (HFE). There is also evidence of a theory-research gap that may be limiting the scientific evidence base of HFE. The purpose of this study was to examine trends in journal publications, especially relating to the research-practice gap and the involvement of theory over time. A content analysis was conducted on 425 journal articles published in Human Factors, Ergonomics, and Applied Ergonomics from 1960 to 2010. Results showed evidence of growth in applied research with increasing collaborative research between research and industry, larger research teams, and more empirical research-especially on applied problems. While there has been a corresponding increase in the involvement of theory in HFE publications, around half of the publications failed to acknowledge theory. This calls into question whether the HFE discipline may be missing the benefits of theory to guide research and subsequent practice, and to enhance the development of new ideas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Numerical Ergonomics Analysis in Operation Environment of CNC Machine

    NASA Astrophysics Data System (ADS)

    Wong, S. F.; Yang, Z. X.

    2010-05-01

    The performance of operator will be affected by different operation environments [1]. Moreover, poor operation environment may cause health problems of the operator [2]. Physical and psychological considerations are two main factors that will affect the performance of operator under different conditions of operation environment. In this paper, applying scientific and systematic methods find out the pivot elements in the field of physical and psychological factors. There are five main factors including light, temperature, noise, air flow and space that are analyzed. A numerical ergonomics model has been built up regarding the analysis results which can support to advance the design of operation environment. Moreover, the output of numerical ergonomic model can provide the safe, comfortable, more productive conditions for the operator.

  9. Medical data mining: knowledge discovery in a clinical data warehouse.

    PubMed Central

    Prather, J. C.; Lobach, D. F.; Goodwin, L. K.; Hales, J. W.; Hage, M. L.; Hammond, W. E.

    1997-01-01

    Clinical databases have accumulated large quantities of information about patients and their medical conditions. Relationships and patterns within this data could provide new medical knowledge. Unfortunately, few methodologies have been developed and applied to discover this hidden knowledge. In this study, the techniques of data mining (also known as Knowledge Discovery in Databases) were used to search for relationships in a large clinical database. Specifically, data accumulated on 3,902 obstetrical patients were evaluated for factors potentially contributing to preterm birth using exploratory factor analysis. Three factors were identified by the investigators for further exploration. This paper describes the processes involved in mining a clinical database including data warehousing, data query and cleaning, and data analysis. PMID:9357597

  10. The Femininity Ideology Scale (FIS): dimensions and its relationship to anxiety and feminine gender role stress.

    PubMed

    Richmond, Katherine; Levant, Ronald; Smalley, Bryant; Cook, Stephen

    2015-01-01

    The purpose of this study was to conduct a confirmatory factor analytic investigation of the Femininity Ideology Scale (FIS) and to assess whether feminine gender role stress mediated the relationship between femininity ideology and anxiety. During the 2010-2011 academic year, a convenience sample of 606 college women were recruited from three universities and one college. Confirmatory factor analysis supported a four- versus the hypothesized five-factor model, resulting in the elimination of the Dependency/Deference factor. Mediation analysis using structural equation modeling indicated no direct relationship between Femininity Ideology and Anxiety, although an indirect one was observed, mediated through Feminine Gender Role Stress. The results are discussed in terms of possible changes in contemporary notions of femininity, and the utility of using the FIS in applied therapeutic settings.

  11. Development, optimization, validation and application of faster gas chromatography - flame ionization detector method for the analysis of total petroleum hydrocarbons in contaminated soils.

    PubMed

    Zubair, Abdulrazaq; Pappoe, Michael; James, Lesley A; Hawboldt, Kelly

    2015-12-18

    This paper presents an important new approach to improving the timeliness of Total Petroleum Hydrocarbon (TPH) analysis in the soil by Gas Chromatography - Flame Ionization Detector (GC-FID) using the CCME Canada-Wide Standard reference method. The Canada-Wide Standard (CWS) method is used for the analysis of petroleum hydrocarbon compounds across Canada. However, inter-laboratory application of this method for the analysis of TPH in the soil has often shown considerable variability in the results. This could be due, in part, to the different gas chromatography (GC) conditions, other steps involved in the method, as well as the soil properties. In addition, there are differences in the interpretation of the GC results, which impacts the determination of the effectiveness of remediation at hydrocarbon-contaminated sites. In this work, multivariate experimental design approach was used to develop and validate the analytical method for a faster quantitative analysis of TPH in (contaminated) soil. A fractional factorial design (fFD) was used to screen six factors to identify the most significant factors impacting the analysis. These factors included: injection volume (μL), injection temperature (°C), oven program (°C/min), detector temperature (°C), carrier gas flow rate (mL/min) and solvent ratio (v/v hexane/dichloromethane). The most important factors (carrier gas flow rate and oven program) were then optimized using a central composite response surface design. Robustness testing and validation of model compares favourably with the experimental results with percentage difference of 2.78% for the analysis time. This research successfully reduced the method's standard analytical time from 20 to 8min with all the carbon fractions eluting. The method was successfully applied for fast TPH analysis of Bunker C oil contaminated soil. A reduced analytical time would offer many benefits including an improved laboratory reporting times, and overall improved clean up efficiency. The method was successfully applied for the analysis of TPH of Bunker C oil in contaminated soil. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  12. The Possible Application of Socioeconomic Careers and Path Analysis Concepts to the Study of Factors Relevant to Physicians' Choice of Practice Location.

    ERIC Educational Resources Information Center

    Grimes, Walter F.

    In response to the current shortage of rural physicians and the difficulties encountered in studying this problem, this paper attempts to apply a specific multivariate technique (path analysis) and the socioeconomic careers model of Featherman and others to the study of the physician's choice of practice location. The socioeconomic careers model…

  13. Transforming Graph Data for Statistical Relational Learning

    DTIC Science & Technology

    2012-10-01

    Jordan, 2003), PLSA (Hofmann, 1999), ? Classification via RMN (Taskar et al., 2003) or SVM (Hasan, Chaoji, Salem , & Zaki, 2006) ? Hierarchical...dimensionality reduction methods such as Principal 407 Rossi, McDowell, Aha, & Neville Component Analysis (PCA), Principal Factor Analysis ( PFA ), and...clustering algorithm. Journal of the Royal Statistical Society. Series C, Applied statistics, 28, 100–108. Hasan, M. A., Chaoji, V., Salem , S., & Zaki, M

  14. Mathematics Low Achievement in Greece: A Multilevel Analysis of the Programme for International Student Assessment (PISA) 2012 Data

    ERIC Educational Resources Information Center

    Karakolidis, Anastasios; Pitsia, Vasiliki; Emvalotis, Anastassios

    2016-01-01

    The main aim of the present study was to carry out an in-depth examination of mathematics underperformance in Greece. By applying a binary multilevel model to the PISA 2012 data, this study investigated the factors which were linked to low achievement in mathematics. The multilevel analysis revealed that students' gender, immigration status,…

  15. Factors underlying the psychological and behavioral characteristics of Office of Strategic Services candidates: the assessment of men data revisited.

    PubMed

    Lenzenweger, Mark F

    2015-01-01

    During World War II, the Office of Strategic Services (OSS), the forerunner of the Central Intelligence Agency, sought the assistance of clinical psychologists and psychiatrists to establish an assessment program for evaluating candidates for the OSS. The assessment team developed a novel and rigorous program to evaluate OSS candidates. It is described in Assessment of Men: Selection of Personnel for the Office of Strategic Services (OSS Assessment Staff, 1948). This study examines the sole remaining multivariate data matrix that includes all final ratings for a group of candidates (n = 133) assessed near the end of the assessment program. It applies the modern statistical methods of both exploratory and confirmatory factor analysis to this rich and highly unique data set. An exploratory factor analysis solution suggested 3 factors underlie the OSS assessment staff ratings. Confirmatory factor analysis results of multiple plausible substantive models reveal that a 3-factor model provides the best fit to these data. The 3 factors are emotional/interpersonal factors (social relations, emotional stability, security), intelligence processing (effective IQ, propaganda skills, observing and reporting), and agency/surgency (motivation, energy and initiative, leadership, physical ability). These factors are discussed in terms of their potential utility for personnel selection within the intelligence community.

  16. Evaluation of hierarchical agglomerative cluster analysis methods for discrimination of primary biological aerosol

    NASA Astrophysics Data System (ADS)

    Crawford, I.; Ruske, S.; Topping, D. O.; Gallagher, M. W.

    2015-07-01

    In this paper we present improved methods for discriminating and quantifying Primary Biological Aerosol Particles (PBAP) by applying hierarchical agglomerative cluster analysis to multi-parameter ultra violet-light induced fluorescence (UV-LIF) spectrometer data. The methods employed in this study can be applied to data sets in excess of 1×106 points on a desktop computer, allowing for each fluorescent particle in a dataset to be explicitly clustered. This reduces the potential for misattribution found in subsampling and comparative attribution methods used in previous approaches, improving our capacity to discriminate and quantify PBAP meta-classes. We evaluate the performance of several hierarchical agglomerative cluster analysis linkages and data normalisation methods using laboratory samples of known particle types and an ambient dataset. Fluorescent and non-fluorescent polystyrene latex spheres were sampled with a Wideband Integrated Bioaerosol Spectrometer (WIBS-4) where the optical size, asymmetry factor and fluorescent measurements were used as inputs to the analysis package. It was found that the Ward linkage with z-score or range normalisation performed best, correctly attributing 98 and 98.1 % of the data points respectively. The best performing methods were applied to the BEACHON-RoMBAS ambient dataset where it was found that the z-score and range normalisation methods yield similar results with each method producing clusters representative of fungal spores and bacterial aerosol, consistent with previous results. The z-score result was compared to clusters generated with previous approaches (WIBS AnalysiS Program, WASP) where we observe that the subsampling and comparative attribution method employed by WASP results in the overestimation of the fungal spore concentration by a factor of 1.5 and the underestimation of bacterial aerosol concentration by a factor of 5. We suggest that this likely due to errors arising from misatrribution due to poor centroid definition and failure to assign particles to a cluster as a result of the subsampling and comparative attribution method employed by WASP. The methods used here allow for the entire fluorescent population of particles to be analysed yielding an explict cluster attribution for each particle, improving cluster centroid definition and our capacity to discriminate and quantify PBAP meta-classes compared to previous approaches.

  17. Factors Associated With Care Workers' Intention to Leave Employment in Nursing Homes: A Secondary Data Analysis of the Swiss Nursing Homes Human Resources Project.

    PubMed

    Gaudenz, Clergia; De Geest, Sabina; Schwendimann, René; Zúñiga, Franziska

    2017-07-01

    The emerging care personnel shortage in Swiss nursing homes is aggravated by high turnover rates. As intention to leave is a predictor of turnover, awareness of its associated factors is essential. This study applied a secondary data analysis to evaluate the prevalence and variability of 3,984 nursing home care workers' intention to leave. Work environment factors and care worker outcomes were tested via multiple regression analysis. Although 56% of care workers reported intention to leave, prevalences varied widely between facilities. Overall, intention to leave showed strong inverse relationships with supportive leadership and affective organizational commitment and weaker positive relationships with stress due to workload, emotional exhaustion, and care worker health problems. The strong direct relationship of nursing home care workers' intention to leave with affective organizational commitment and perceptions of leadership quality suggest that multilevel interventions to improve these factors might reduce intention to leave.

  18. Landslides distribution analysis and role of triggering factors in the Foglia river basin (Central Itay)

    NASA Astrophysics Data System (ADS)

    Baioni, Davide; Gallerini, Giuliano; Sgavetti, Maria

    2013-04-01

    The present work is focused on the distribution of landslides in Foglia river basin area (northern Marche-Romagna), using a heuristic approach supported by GIS tools for the construction of statistical analysis and spatial data. The study area is located in the Adriatic side of the northern Apennine in the boundary that marks the transition between the Marche and Emilia-Romagna regions. The Foglia river basin extends from the Apennines to the Adriatic sea with NE-SE trend occupying an area of about 708 km2. The purpose of this study is to investigate any relationships between factors related to the territory, which were taken into account and divided into classes, and landslides, trying to identify any possible existence of relationships between them. For this aim the study of landslides distribution was performed by using a GIS approach superimposing each thematic map, previously created, with landslides surveyed. Furthermore, we tried to isolate the most recurrent classes, to detect if at the same conditions there is a parameter that affects more than others, so as to recognize every direct relationship of cause and effect. Finally, an analysis was conducted by applying the model of uncertainty CF (Certainity Factor). In the Foglia river basin were surveyed a total of 2821 landslides occupy a total area of 155 km2, corresponding to 22% areal extent of the entire basin. The results of analysis carried out highlighted the importance and role of individual factors that led to the development of landslides analyzed. Moreover, this methodology may be applied to all orders of magnitude and scale without any problem by not requiring a commitment important, both from the economic point of view, and of human resources.

  19. Argon-oxygen atmospheric pressure plasma treatment on carbon fiber reinforced polymer for improved bonding

    NASA Astrophysics Data System (ADS)

    Chartosias, Marios

    Acceptance of Carbon Fiber Reinforced Polymer (CFRP) structures requires a robust surface preparation method with improved process controls capable of ensuring high bond quality. Surface preparation in a production clean room environment prior to applying adhesive for bonding would minimize risk of contamination and reduce cost. Plasma treatment is a robust surface preparation process capable of being applied in a production clean room environment with process parameters that are easily controlled and documented. Repeatable and consistent processing is enabled through the development of a process parameter window utilizing techniques such as Design of Experiments (DOE) tailored to specific adhesive and substrate bonding applications. Insight from respective plasma treatment Original Equipment Manufacturers (OEMs) and screening tests determined critical process factors from non-factors and set the associated factor levels prior to execution of the DOE. Results from mode I Double Cantilever Beam (DCB) testing per ASTM D 5528 [1] standard and DOE statistical analysis software are used to produce a regression model and determine appropriate optimum settings for each factor.

  20. Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS)

    NASA Technical Reports Server (NTRS)

    Alexander, Tiffaney Miller

    2017-01-01

    Research results have shown that more than half of aviation, aerospace and aeronautics mishaps incidents are attributed to human error. As a part of Safety within space exploration ground processing operations, the identification and/or classification of underlying contributors and causes of human error must be identified, in order to manage human error. This research provides a framework and methodology using the Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS), as an analysis tool to identify contributing factors, their impact on human error events, and predict the Human Error probabilities (HEPs) of future occurrences. This research methodology was applied (retrospectively) to six (6) NASA ground processing operations scenarios and thirty (30) years of Launch Vehicle related mishap data. This modifiable framework can be used and followed by other space and similar complex operations.

  1. Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS)

    NASA Technical Reports Server (NTRS)

    Alexander, Tiffaney Miller

    2017-01-01

    Research results have shown that more than half of aviation, aerospace and aeronautics mishaps/incidents are attributed to human error. As a part of Safety within space exploration ground processing operations, the identification and/or classification of underlying contributors and causes of human error must be identified, in order to manage human error. This research provides a framework and methodology using the Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS), as an analysis tool to identify contributing factors, their impact on human error events, and predict the Human Error probabilities (HEPs) of future occurrences. This research methodology was applied (retrospectively) to six (6) NASA ground processing operations scenarios and thirty (30) years of Launch Vehicle related mishap data. This modifiable framework can be used and followed by other space and similar complex operations.

  2. Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS)

    NASA Technical Reports Server (NTRS)

    Alexander, Tiffaney Miller

    2017-01-01

    Research results have shown that more than half of aviation, aerospace and aeronautics mishaps incidents are attributed to human error. As a part of Quality within space exploration ground processing operations, the identification and or classification of underlying contributors and causes of human error must be identified, in order to manage human error.This presentation will provide a framework and methodology using the Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS), as an analysis tool to identify contributing factors, their impact on human error events, and predict the Human Error probabilities (HEPs) of future occurrences. This research methodology was applied (retrospectively) to six (6) NASA ground processing operations scenarios and thirty (30) years of Launch Vehicle related mishap data. This modifiable framework can be used and followed by other space and similar complex operations.

  3. Validation of the Weight Concerns Scale Applied to Brazilian University Students.

    PubMed

    Dias, Juliana Chioda Ribeiro; da Silva, Wanderson Roberto; Maroco, João; Campos, Juliana Alvares Duarte Bonini

    2015-06-01

    The aim of this study was to evaluate the validity and reliability of the Portuguese version of the Weight Concerns Scale (WCS) when applied to Brazilian university students. The scale was completed by 1084 university students from Brazilian public education institutions. A confirmatory factor analysis was conducted. The stability of the model in independent samples was assessed through multigroup analysis, and the invariance was estimated. Convergent, concurrent, divergent, and criterion validities as well as internal consistency were estimated. Results indicated that the one-factor model presented an adequate fit to the sample and values of convergent validity. The concurrent validity with the Body Shape Questionnaire and divergent validity with the Maslach Burnout Inventory for Students were adequate. Internal consistency was adequate, and the factorial structure was invariant in independent subsamples. The results present a simple and short instrument capable of precisely and accurately assessing concerns with weight among Brazilian university students. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Using Separable Nonnegative Matrix Factorization Techniques for the Analysis of Time-Resolved Raman Spectra

    NASA Astrophysics Data System (ADS)

    Luce, R.; Hildebrandt, P.; Kuhlmann, U.; Liesen, J.

    2016-09-01

    The key challenge of time-resolved Raman spectroscopy is the identification of the constituent species and the analysis of the kinetics of the underlying reaction network. In this work we present an integral approach that allows for determining both the component spectra and the rate constants simultaneously from a series of vibrational spectra. It is based on an algorithm for non-negative matrix factorization which is applied to the experimental data set following a few pre-processing steps. As a prerequisite for physically unambiguous solutions, each component spectrum must include one vibrational band that does not significantly interfere with vibrational bands of other species. The approach is applied to synthetic "experimental" spectra derived from model systems comprising a set of species with component spectra differing with respect to their degree of spectral interferences and signal-to-noise ratios. In each case, the species involved are connected via monomolecular reaction pathways. The potential and limitations of the approach for recovering the respective rate constants and component spectra are discussed.

  5. Spatial Analysis of Ambient PM2.5 Exposure and Bladder Cancer Mortality in Taiwan

    PubMed Central

    Yeh, Hsin-Ling; Hsu, Shang-Wei; Chang, Yu-Chia; Chan, Ta-Chien; Tsou, Hui-Chen; Chang, Yen-Chen; Chiang, Po-Huang

    2017-01-01

    Fine particulate matter (PM2.5) is an air pollutant that is receiving intense regulatory attention in Taiwan. In previous studies, the effect of air pollution on bladder cancer has been explored. This study was conducted to elucidate the effect of atmospheric PM2.5 and other local risk factors on bladder cancer mortality based on available 13-year mortality data. Geographically weighted regression (GWR) was applied to estimate and interpret the spatial variability of the relationships between bladder cancer mortality and ambient PM2.5 concentrations, and other variables were covariates used to adjust for the effect of PM2.5. After applying a GWR model, the concentration of ambient PM2.5 showed a positive correlation with bladder cancer mortality in males in northern Taiwan and females in most of the townships in Taiwan. This is the first time PM2.5 has been identified as a risk factor for bladder cancer based on the statistical evidence provided by GWR analysis. PMID:28489042

  6. Analysis of algae growth mechanism and water bloom prediction under the effect of multi-affecting factor.

    PubMed

    Wang, Li; Wang, Xiaoyi; Jin, Xuebo; Xu, Jiping; Zhang, Huiyan; Yu, Jiabin; Sun, Qian; Gao, Chong; Wang, Lingbin

    2017-03-01

    The formation process of algae is described inaccurately and water blooms are predicted with a low precision by current methods. In this paper, chemical mechanism of algae growth is analyzed, and a correlation analysis of chlorophyll-a and algal density is conducted by chemical measurement. Taking into account the influence of multi-factors on algae growth and water blooms, the comprehensive prediction method combined with multivariate time series and intelligent model is put forward in this paper. Firstly, through the process of photosynthesis, the main factors that affect the reproduction of the algae are analyzed. A compensation prediction method of multivariate time series analysis based on neural network and Support Vector Machine has been put forward which is combined with Kernel Principal Component Analysis to deal with dimension reduction of the influence factors of blooms. Then, Genetic Algorithm is applied to improve the generalization ability of the BP network and Least Squares Support Vector Machine. Experimental results show that this method could better compensate the prediction model of multivariate time series analysis which is an effective way to improve the description accuracy of algae growth and prediction precision of water blooms.

  7. Bayesian structural equation modeling: a more flexible representation of substantive theory.

    PubMed

    Muthén, Bengt; Asparouhov, Tihomir

    2012-09-01

    This article proposes a new approach to factor analysis and structural equation modeling using Bayesian analysis. The new approach replaces parameter specifications of exact zeros with approximate zeros based on informative, small-variance priors. It is argued that this produces an analysis that better reflects substantive theories. The proposed Bayesian approach is particularly beneficial in applications where parameters are added to a conventional model such that a nonidentified model is obtained if maximum-likelihood estimation is applied. This approach is useful for measurement aspects of latent variable modeling, such as with confirmatory factor analysis, and the measurement part of structural equation modeling. Two application areas are studied, cross-loadings and residual correlations in confirmatory factor analysis. An example using a full structural equation model is also presented, showing an efficient way to find model misspecification. The approach encompasses 3 elements: model testing using posterior predictive checking, model estimation, and model modification. Monte Carlo simulations and real data are analyzed using Mplus. The real-data analyses use data from Holzinger and Swineford's (1939) classic mental abilities study, Big Five personality factor data from a British survey, and science achievement data from the National Educational Longitudinal Study of 1988.

  8. Investigation of High-Angle-of-Attack Maneuver-Limiting Factors. Part 1. Analysis and Simulation

    DTIC Science & Technology

    1980-12-01

    useful, are not so satisfying or in- structive as the more positive identification of causal factors offered by the methods developed in Reference 5...same methods be applied to additional high-performance fighter aircraft having widely differing high AOA handling characteristics to see if further...predictions and the nonlinear model results were resolved. The second task involved development of methods , criteria, and an associated pilot rating scale, for

  9. An Analysis of Promotion and Retention Factors Among Hispanic and Non-Hispanic Marine Corps Officers

    DTIC Science & Technology

    2015-03-01

    PROMOTION AND RETENTION FACTORS AMONG HISPANIC AND NON-HISPANIC MARINE CORPS OFFICERS by Mateo E. Salas March 2015 Thesis Advisor: Simona...U.S. This thesis reviews Marine Corps policies on the recruitment, retention , and promotion of talented officers of a diverse background, and applies...source, military training and fitness report scores that explain any differences in job performance measures of Marine Corps officers of different ethnic

  10. Information Center Help Desk

    DTIC Science & Technology

    1991-09-01

    listed is made. Many factors beyond what is included in the short list of features go into making that decision. Data on optical disk drives, scanners and...support existed due to lack of hardware or software. To do this analysis the IC responses were studied in relationship to the following three issues...each based on the developed criteria. No weighting factors in terms of relative importance of each criteria can be applied in this environment. As

  11. Rapid acquisition and model-based analysis of cell-free transcription–translation reactions from nonmodel bacteria

    PubMed Central

    Wienecke, Sarah; Ishwarbhai, Alka; Tsipa, Argyro; Aw, Rochelle; Kylilis, Nicolas; Bell, David J.; McClymont, David W.; Jensen, Kirsten; Biedendieck, Rebekka

    2018-01-01

    Native cell-free transcription–translation systems offer a rapid route to characterize the regulatory elements (promoters, transcription factors) for gene expression from nonmodel microbial hosts, which can be difficult to assess through traditional in vivo approaches. One such host, Bacillus megaterium, is a giant Gram-positive bacterium with potential biotechnology applications, although many of its regulatory elements remain uncharacterized. Here, we have developed a rapid automated platform for measuring and modeling in vitro cell-free reactions and have applied this to B. megaterium to quantify a range of ribosome binding site variants and previously uncharacterized endogenous constitutive and inducible promoters. To provide quantitative models for cell-free systems, we have also applied a Bayesian approach to infer ordinary differential equation model parameters by simultaneously using time-course data from multiple experimental conditions. Using this modeling framework, we were able to infer previously unknown transcription factor binding affinities and quantify the sharing of cell-free transcription–translation resources (energy, ribosomes, RNA polymerases, nucleotides, and amino acids) using a promoter competition experiment. This allows insights into resource limiting-factors in batch cell-free synthesis mode. Our combined automated and modeling platform allows for the rapid acquisition and model-based analysis of cell-free transcription–translation data from uncharacterized microbial cell hosts, as well as resource competition within cell-free systems, which potentially can be applied to a range of cell-free synthetic biology and biotechnology applications. PMID:29666238

  12. Asymmetric flow field flow fractionation with light scattering detection - an orthogonal sensitivity analysis.

    PubMed

    Galyean, Anne A; Filliben, James J; Holbrook, R David; Vreeland, Wyatt N; Weinberg, Howard S

    2016-11-18

    Asymmetric flow field flow fractionation (AF 4 ) has several instrumental factors that may have a direct effect on separation performance. A sensitivity analysis was applied to ascertain the relative importance of AF 4 primary instrument factor settings for the separation of a complex environmental sample. The analysis evaluated the impact of instrumental factors namely, cross flow, ramp time, focus flow, injection volume, and run buffer concentration on the multi-angle light scattering measurement of natural organic matter (NOM) molar mass (MM). A 2 (5-1) orthogonal fractional factorial design was used to minimize analysis time while preserving the accuracy and robustness in the determination of the main effects and interactions between any two instrumental factors. By assuming that separations resulting in smaller MM measurements would be more accurate, the analysis produced a ranked list of effects estimates for factors and interactions of factors based on their relative importance in minimizing the MM. The most important and statistically significant AF 4 instrumental factors were buffer concentration and cross flow. The least important was ramp time. A parallel 2 (5-2) orthogonal fractional factorial design was also employed on five environmental factors for synthetic natural water samples containing silver nanoparticles (NPs), namely: NP concentration, NP size, NOM concentration, specific conductance, and pH. None of the water quality characteristic effects or interactions were found to be significant in minimizing the measured MM; however, the interaction between NP concentration and NP size was an important effect when considering NOM recovery. This work presents a structured approach for the rigorous assessment of AF 4 instrument factors and optimal settings for the separation of complex samples utilizing efficient orthogonal factional factorial design and appropriate graphical analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. A systematic review of the relationship factor between women and health professionals within the multivariant analysis of maternal satisfaction.

    PubMed

    Macpherson, Ignacio; Roqué-Sánchez, María V; Legget Bn, Finola O; Fuertes, Ferran; Segarra, Ignacio

    2016-10-01

    personalised support provided to women by health professionals is one of the prime factors attaining women's satisfaction during pregnancy and childbirth. However the multifactorial nature of 'satisfaction' makes difficult to assess it. Statistical multivariate analysis may be an effective technique to obtain in depth quantitative evidence of the importance of this factor and its interaction with the other factors involved. This technique allows us to estimate the importance of overall satisfaction in its context and suggest actions for healthcare services. systematic review of studies that quantitatively measure the personal relationship between women and healthcare professionals (gynecologists, obstetricians, nurse, midwifes, etc.) regarding maternity care satisfaction. The literature search focused on studies carried out between 1970 and 2014 that used multivariate analyses and included the woman-caregiver relationship as a factor of their analysis. twenty-four studies which applied various multivariate analysis tools to different periods of maternity care (antenatal, perinatal, post partum) were selected. The studies included discrete scale scores and questionnaires from women with low-risk pregnancies. The "personal relationship" factor appeared under various names: care received, personalised treatment, professional support, amongst others. The most common multivariate techniques used to assess the percentage of variance explained and the odds ratio of each factor were principal component analysis and logistic regression. the data, variables and factor analysis suggest that continuous, personalised care provided by the usual midwife and delivered within a family or a specialised setting, generates the highest level of satisfaction. In addition, these factors foster the woman's psychological and physiological recovery, often surpassing clinical action (e.g. medicalization and hospital organization) and/or physiological determinants (e.g. pain, pathologies, etc.). Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Comparison of Seven Methods for Boolean Factor Analysis and Their Evaluation by Information Gain.

    PubMed

    Frolov, Alexander A; Húsek, Dušan; Polyakov, Pavel Yu

    2016-03-01

    An usual task in large data set analysis is searching for an appropriate data representation in a space of fewer dimensions. One of the most efficient methods to solve this task is factor analysis. In this paper, we compare seven methods for Boolean factor analysis (BFA) in solving the so-called bars problem (BP), which is a BFA benchmark. The performance of the methods is evaluated by means of information gain. Study of the results obtained in solving BP of different levels of complexity has allowed us to reveal strengths and weaknesses of these methods. It is shown that the Likelihood maximization Attractor Neural Network with Increasing Activity (LANNIA) is the most efficient BFA method in solving BP in many cases. Efficacy of the LANNIA method is also shown, when applied to the real data from the Kyoto Encyclopedia of Genes and Genomes database, which contains full genome sequencing for 1368 organisms, and to text data set R52 (from Reuters 21578) typically used for label categorization.

  15. Numerical simulation and analysis of accurate blood oxygenation measurement by using optical resolution photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Yu, Tianhao; Li, Qian; Li, Lin; Zhou, Chuanqing

    2016-10-01

    Accuracy of photoacoustic signal is the crux on measurement of oxygen saturation in functional photoacoustic imaging, which is influenced by factors such as defocus of laser beam, curve shape of large vessels and nonlinear saturation effect of optical absorption in biological tissues. We apply Monte Carlo model to simulate energy deposition in tissues and obtain photoacoustic signals reaching a simulated focused surface detector to investigate corresponding influence of these factors. We also apply compensation on photoacoustic imaging of in vivo cat cerebral cortex blood vessels, in which signals from different lateral positions of vessels are corrected based on simulation results. And this process on photoacoustic images can improve the smoothness and accuracy of oxygen saturation results.

  16. Trends in Women's Participation at the Meetings of the Association for Behavior Analysis: 1975–2005

    PubMed Central

    Simon, Jennifer L; Morris, Edward K; Smith, Nathaniel G

    2007-01-01

    We examined women's participation, relative to men's, at the annual meetings of the Association for Behavior Analysis (ABA) between 1975 and 2005. Among our findings are upward trends in female presenters across formats (e.g., posters), types of authorship (e.g., first authors), and specialty areas (e.g., autism). Where women have attained parity, however, they are still often underrepresented, given their percentage of membership. Women also participate less than men as sole and invited authors and discussants and in the domains of basic research and conceptual analysis, but participate more than men in the applied domain. Data from the Journal of the Experimental Analysis of Behavior and the Journal of Applied Behavior Analysis show parallel but delayed trends toward parity in basic and applied research, whereas data from The Behavior Analyst show only modest gains in the conceptual domain. We discuss the gender disparities in ABA's more prestigious categories of participation (e.g., invited addresses) and across its content domains, as well as in science in general, and the role of social and cultural factors in producing the disparities and how behavior analysts might aid in correcting them. PMID:22478496

  17. A computational intelligent approach to multi-factor analysis of violent crime information system

    NASA Astrophysics Data System (ADS)

    Liu, Hongbo; Yang, Chao; Zhang, Meng; McLoone, Seán; Sun, Yeqing

    2017-02-01

    Various scientific studies have explored the causes of violent behaviour from different perspectives, with psychological tests, in particular, applied to the analysis of crime factors. The relationship between bi-factors has also been extensively studied including the link between age and crime. In reality, many factors interact to contribute to criminal behaviour and as such there is a need to have a greater level of insight into its complex nature. In this article we analyse violent crime information systems containing data on psychological, environmental and genetic factors. Our approach combines elements of rough set theory with fuzzy logic and particle swarm optimisation to yield an algorithm and methodology that can effectively extract multi-knowledge from information systems. The experimental results show that our approach outperforms alternative genetic algorithm and dynamic reduct-based techniques for reduct identification and has the added advantage of identifying multiple reducts and hence multi-knowledge (rules). Identified rules are consistent with classical statistical analysis of violent crime data and also reveal new insights into the interaction between several factors. As such, the results are helpful in improving our understanding of the factors contributing to violent crime and in highlighting the existence of hidden and intangible relationships between crime factors.

  18. National Institutes of Health Toolbox Emotion Battery for English- and Spanish-speaking adults: normative data and factor-based summary scores.

    PubMed

    Babakhanyan, Ida; McKenna, Benjamin S; Casaletto, Kaitlin B; Nowinski, Cindy J; Heaton, Robert K

    2018-01-01

    The National Institutes of Health Toolbox Emotion Battery (NIHTB-EB) is a "common currency", computerized assessment developed to measure the full spectrum of emotional health. Though comprehensive, the NIHTB-EB's 17 scales may be unwieldy for users aiming to capture more global indices of emotional functioning. NIHTB-EB was administered to 1,036 English-speaking and 408 Spanish-speaking adults as a part of the NIH Toolbox norming project. We examined the factor structure of the NIHTB-EB in English- and Spanish-speaking adults and developed factor analysis-based summary scores. Census-weighted norms were presented for English speakers, and sample-weighted norms were presented for Spanish speakers. Exploratory factor analysis for both English- and Spanish-speaking cohorts resulted in the same 3-factor solution: 1) negative affect, 2) social satisfaction, and 3) psychological well-being. Confirmatory factor analysis supported similar factor structures for English- and Spanish-speaking cohorts. Model fit indices fell within the acceptable/good range, and our final solution was optimal compared to other solutions. Summary scores based upon the normative samples appear to be psychometrically supported and should be applied to clinical samples to further validate the factor structures and investigate rates of problematic emotions in medical and psychiatric populations.

  19. GC-MS analyses and chemometric processing to discriminate the local and long-distance sources of PAHs associated to atmospheric PM2.5.

    PubMed

    Masiol, Mauro; Centanni, Elena; Squizzato, Stefania; Hofer, Angelika; Pecorari, Eliana; Rampazzo, Giancarlo; Pavoni, Bruno

    2012-09-01

    This study presents a procedure to differentiate the local and remote sources of particulate-bound polycyclic aromatic hydrocarbons (PAHs). Data were collected during an extended PM(2.5) sampling campaign (2009-2010) carried out for 1 year in Venice-Mestre, Italy, at three stations with different emissive scenarios: urban, industrial, and semirural background. Diagnostic ratios and factor analysis were initially applied to point out the most probable sources. In a second step, the areal distribution of the identified sources was studied by applying the discriminant analysis on factor scores. Third, samples collected in days with similar atmospheric circulation patterns were grouped using a cluster analysis on wind data. Local contributions to PM(2.5) and PAHs were then assessed by interpreting cluster results with chemical data. Results evidenced that significantly lower levels of PM(2.5) and PAHs were found when faster winds changed air masses, whereas in presence of scarce ventilation, locally emitted pollutants were trapped and concentrations increased. This way, an estimation of pollutant loads due to local sources can be derived from data collected in days with similar wind patterns. Long-range contributions were detected by a cluster analysis on the air mass back-trajectories. Results revealed that PM(2.5) concentrations were relatively high when air masses had passed over the Po Valley. However, external sources do not significantly contribute to the PAHs load. The proposed procedure can be applied to other environments with minor modifications, and the obtained information can be useful to design local and national air pollution control strategies.

  20. Psychometric properties of the Internet Addiction Test in Turkish

    PubMed Central

    Kaya, Fatih; Delen, Erhan; Young, Kimberly S.

    2016-01-01

    Background and aims In this study, the Internet Addiction Test (IAT) was adapted to Turkish language, which was originally developed by Young (1998) in English to measure the presence and severity of the Internet dependency. The main purpose was to ensure that the psychometric features and the factor structure of the test were suitable for Turkish university students. Method The study was conducted in two sequent phases. Participants were 990 undergraduate students from several public universities in Turkey. Results In the first phase, an exploratory factor analysis (EFA) was applied to figure out the factor structure of the Turkish version of the IAT. The EFA revealed four factors, which explained 46.02% of the total variance. In the following phase, a confirmatory factor analysis (CFA) was conducted with a different sample, to verify the factor structure that was found in the initial EFA. The CFA resulted four-factor model was satisfactory for the Turkish version of the IAT. These four factors were named as Mood, Relationship, Responsibilities, and Duration. Conclusions Based on the findings, the administration of Turkish version of the IAT provided acceptable results on undergraduate students. PMID:28092191

  1. Remote sensing applied to agriculture: Basic principles, methodology, and applications

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Mendonca, F. J.

    1981-01-01

    The general principles of remote sensing techniques as applied to agriculture and the methods of data analysis are described. the theoretical spectral responses of crops; reflectance, transmittance, and absorbtance of plants; interactions of plants and soils with reflectance energy; leaf morphology; and factors which affect the reflectance of vegetation cover are dicussed. The methodologies of visual and computer-aided analyses of LANDSAT data are presented. Finally, a case study wherein infrared film was used to detect crop anomalies and other data applications are described.

  2. Chemical factor analysis of skin cancer FTIR-FEW spectroscopic data

    NASA Astrophysics Data System (ADS)

    Bruch, Reinhard F.; Sukuta, Sydney

    2002-03-01

    Chemical Factor Analysis (CFA) algorithms were applied to transform complex Fourier transform infrared fiberoptical evanescent wave (FTIR-FEW) normal and malignant skin tissue spectra into factor spaces for analysis and classification. The factor space approach classified melanoma beyond prior pathological classifications related to specific biochemical alterations to health states in cluster diagrams allowing diagnosis with more biochemical specificity, resolving biochemical component spectra and employing health state eigenvector angular configurations as disease state sensors. This study demonstrated a wealth of new information from in vivo FTIR-FEW spectral tissue data, without extensive a priori information or clinically invasive procedures. In particular, we employed a variety of methods used in CFA to select the rank of spectroscopic data sets of normal benign and cancerous skin tissue. We used the Malinowski indicator function (IND), significance level and F-Tests to rank our data matrices. Normal skin tissue, melanoma and benign tumors were modeled by four, two and seven principal abstract factors, respectively. We also showed that the spectrum of the first eigenvalue was equivalent to the mean spectrum. The graphical depiction of angular disparities between the first abstract factors can be adopted as a new way to characterize and diagnose melanoma cancer.

  3. Groundwater flow and hydrogeochemical evolution in the Jianghan Plain, central China

    NASA Astrophysics Data System (ADS)

    Gan, Yiqun; Zhao, Ke; Deng, Yamin; Liang, Xing; Ma, Teng; Wang, Yanxin

    2018-05-01

    Hydrogeochemical analysis and multivariate statistics were applied to identify flow patterns and major processes controlling the hydrogeochemistry of groundwater in the Jianghan Plain, which is located in central Yangtze River Basin (central China) and characterized by intensive surface-water/groundwater interaction. Although HCO3-Ca-(Mg) type water predominated in the study area, the 457 (21 surface water and 436 groundwater) samples were effectively classified into five clusters by hierarchical cluster analysis. The hydrochemical variations among these clusters were governed by three factors from factor analysis. Major components (e.g., Ca, Mg and HCO3) in surface water and groundwater originated from carbonate and silicate weathering (factor 1). Redox conditions (factor 2) influenced the geogenic Fe and As contamination in shallow confined groundwater. Anthropogenic activities (factor 3) primarily caused high levels of Cl and SO4 in surface water and phreatic groundwater. Furthermore, the factor score 1 of samples in the shallow confined aquifer gradually increased along the flow paths. This study demonstrates that enhanced information on hydrochemistry in complex groundwater flow systems, by multivariate statistical methods, improves the understanding of groundwater flow and hydrogeochemical evolution due to natural and anthropogenic impacts.

  4. Confirmatory Factor Analysis of the Malay Version Comprehensive Feeding Practices Questionnaire Tested among Mothers of Primary School Children in Malaysia

    PubMed Central

    Shohaimi, Shamarina; Yoke Wei, Wong; Mohd Shariff, Zalilah

    2014-01-01

    Comprehensive feeding practices questionnaire (CFPQ) is an instrument specifically developed to evaluate parental feeding practices. It has been confirmed among children in America and applied to populations in France, Norway, and New Zealand. In order to extend the application of CFPQ, we conducted a factor structure validation of the translated version of CFPQ (CFPQ-M) using confirmatory factor analysis among mothers of primary school children (N = 397) in Malaysia. Several items were modified for cultural adaptation. Of 49 items, 39 items with loading factors >0.40 were retained in the final model. The confirmatory factor analysis revealed that the final model (twelve-factor model with 39 items and 2 error covariances) displayed the best fit for our sample (Chi-square = 1147; df = 634; P < 0.05; CFI = 0.900; RMSEA = 0.045; SRMR = 0.0058). The instrument with some modifications was confirmed among mothers of school children in Malaysia. The present study extends the usability of the CFPQ and enables researchers and parents to better understand the relationships between parental feeding practices and related problems such as childhood obesity. PMID:25538958

  5. The relationship between constructivist supervisory practices, school climate, and student proficiency in reading, mathematics, and science: Evidence from NELS:88

    NASA Astrophysics Data System (ADS)

    Molnar, John Alexander

    In an effort to improve instruction and student learning, school reform efforts have become prevalent. School reformers have examined many aspects of the school experience, including learning theories such as behaviorism and constructivism, the changing roles of teachers and supervisors, and even the concept of the school itself. The theoretical framework for this study centered around constructivist learning theory. The study itself focused on the application of constructivist learning theory to the supervisory process. The study examined five areas of interest: (a) teachers' perceptions of constructivist supervisory behavior; (b) teachers' perceptions of efficacy and control in the classroom; (c) teachers' perceptions of school climate; (d) teachers' perceptions of job satisfaction, and (e) the influences of each of the aforementioned on student proficiency in mathematics, reading, and science. Data for the study was drawn from the first follow-up survey of the National Educational Longitudinal Study of 1988 (NELS: 88). NELS: 88 investigated a wide variety of factors that influence the educational process. The first follow-up focuses on environmental factors that affect teachers and students. Variables were selected from the NELS:88 data set that represented the areas to be examined. Factor analysis and correlational analysis were applied to ensure that the variables were measuring distinct constructs and to determine ways they could be grouped for analysis. Multiple linear regression analysis was applied to determine relationships among the individual and composite variables, controlling for student and teacher demographic factors. The results of the study suggest that varying relationships do exist between constructivist supervisory practices and the constructs measuring school climate and job satisfaction. The results also suggest that varying relationships exist between each of these factors and student proficiency in mathematics, reading, and science. Specifically, school climate, job satisfaction, and student proficiency were influenced by constructivist supervisory practices that included teachers' freedom to experiment with teaching and teachers' control over texts and materials.

  6. Combine bivariate statistics analysis and multivariate statistics analysis to assess landslide susceptibility in Chen-Yu-Lan watershed, Nantou, Taiwan.

    NASA Astrophysics Data System (ADS)

    Ngan Nguyen, Thi To; Liu, Cheng-Chien

    2013-04-01

    How landslides occurred and which factors triggered and sped up landslide occurrences were usually asked by researchers in the past decades. Many investigations carried out in many places in the world to finding out methods that predict and prevent damages from landslides phenomena. Chen-Yu-Lan River watershed is reputed as a 'hot pot' of landslide researches in Taiwan by its complicated geological structures with the significant tectonic fault systems and steeply mountainous terrain. Beside annual high precipitation concentration and the abrupt slopes, some natural disaster, as typhoons (Sinlaku-2008, Kalmaegi-2008, and Marakot-2009) and earthquake (Chi-Chi earthquake-1999) are also the triggered factors cause landslides with serious damages in this place. This research expresses the quantitative approaches to generate landslide susceptible map for Chen-Yu-Lan watershed, a mountainous area in the central Taiwan. Landslide inventories data, which were detected from the Formosat-2 imageries for eight years from 2004 to 2011, were applied to carry out landslide susceptibility mapping. Bivariate statistics analysis and multivariate statistics analysis would be applied to calculate susceptible index of landslides. The weights of parameters were computed based on landslide data for eight years from 2004 to 2011. To validate effective levels of factors to landslide occurrences, this method built some multivariate algorithms and compared these results with real landslide occurrences. Besides this method, the historical data of landslides were also used to assess and classify landslide susceptibility levels. From long-term landslide data, relation between landslide susceptibility levels and landslide repetition was assigned. The results demonstrated differently effective levels of potential factors, such as, slope gradient, drainage density, lithology and land use to landslide phenomena. The results also showed logical relationship between weights and characteristics of factors' classes. Depending on these results be able to help planning managers localize the high risk areas of landslide or safely areas by building and human activities.

  7. Scientific Elitism and the Information System of Science

    ERIC Educational Resources Information Center

    Amick, Daniel James

    1973-01-01

    Scientific elitism must be viewed as a multidimensional phenomenon. Ten variables of elitism are considered and a principal components factor analysis is used to scale this multivariate domain. Two significant dimensions of elitism were found; one in basic and one in applied science. (20 references) (Author)

  8. SOCIAL PSYCHOLOGICAL FACTORS IN KNOWLEDGE UTILIZATION AS APPLIED TO EDUCATIONAL ADMINISTRATION.

    ERIC Educational Resources Information Center

    SCHMUCK, RICHARD

    THREE PROBLEM AREAS ARE EXPLORED IN THIS SOCIAL PSYCHOLOGICAL ANALYSIS OF RESEARCH UTILIZATION IN EDUCATIONAL ADMINISTRATION--(1) INTERPERSONAL RELATIONSHIPS BETWEEN BEHAVIORAL SCIENTISTS AND SCHOOL ADMINISTRATORS, (2) PSYCHOLOGICAL LINKAGES BETWEEN THE ADMINISTRATOR'S SCIENTIFIC KNOWLEDGE AND HIS ACTIONS, AND (3) THE LACK OF CONNECTION BETWEEN…

  9. Multiple Hypnotizabilities: Differentiating the Building Blocks of Hypnotic Response

    ERIC Educational Resources Information Center

    Woody, Erik Z.; Barnier, Amanda J.; McConkey, Kevin M.

    2005-01-01

    Although hypnotizability can be conceptualized as involving component subskills, standard measures do not differentiate them from a more general unitary trait, partly because the measures include limited sets of dichotomous items. To overcome this, the authors applied full-information factor analysis, a sophisticated analytic approach for…

  10. Population Analysis: Communicating About Anthropometry in Context

    NASA Technical Reports Server (NTRS)

    Thaxton, Sherry; Rajulu, Sudhakar

    2009-01-01

    This slide presentation reviews the importance of communications about anthropometry and population analysis in particular for the design of aerospace systems. The difficulty of providing anthropometric accomodation an entire range of the population is reviewed, and the importance of communication of the issues with human system integration is emphasized, and the analysis of population as it applies to existing human factors methodologies is a novel way to assist with the communication. The issues of space suit design and anthropometry is reviewed as an example.

  11. Development of indirect EFBEM for radiating noise analysis including underwater problems

    NASA Astrophysics Data System (ADS)

    Kwon, Hyun-Wung; Hong, Suk-Yoon; Song, Jee-Hun

    2013-09-01

    For the analysis of radiating noise problems in medium-to-high frequency ranges, the Energy Flow Boundary Element Method (EFBEM) was developed. EFBEM is the analysis technique that applies the Boundary Element Method (BEM) to Energy Flow Analysis (EFA). The fundamental solutions representing spherical wave property for radiating noise problems in open field and considering the free surface effect in underwater are developed. Also the directivity factor is developed to express wave's directivity patterns in medium-to-high frequency ranges. Indirect EFBEM by using fundamental solutions and fictitious source was applied to open field and underwater noise problems successfully. Through numerical applications, the acoustic energy density distributions due to vibration of a simple plate model and a sphere model were compared with those of commercial code, and the comparison showed good agreement in the level and pattern of the energy density distributions.

  12. Spatial Resolution Effects of Digital Terrain Models on Landslide Susceptibility Analysis

    NASA Astrophysics Data System (ADS)

    Chang, K. T.; Dou, J.; Chang, Y.; Kuo, C. P.; Xu, K. M.; Liu, J. K.

    2016-06-01

    The purposes of this study are to identify the maximum number of correlated factors for landslide susceptibility mapping and to evaluate landslide susceptibility at Sihjhong river catchment in the southern Taiwan, integrating two techniques, namely certainty factor (CF) and artificial neural network (ANN). The landslide inventory data of the Central Geological Survey (CGS, MOEA) in 2004-2014 and two digital elevation model (DEM) datasets including a 5-meter LiDAR DEM and a 30-meter Aster DEM were prepared. We collected thirteen possible landslide-conditioning factors. Considering the multi-collinearity and factor redundancy, we applied the CF approach to optimize these thirteen conditioning factors. We hypothesize that if the CF values of the thematic factor layers are positive, it implies that these conditioning factors have a positive relationship with the landslide occurrence. Therefore, based on this assumption and positive CF values, seven conditioning factors including slope angle, slope aspect, elevation, terrain roughness index (TRI), terrain position index (TPI), total curvature, and lithology have been selected for further analysis. The results showed that the optimized-factors model provides a better accuracy for predicting landslide susceptibility in the study area. In conclusion, the optimized-factors model is suggested for selecting relative factors of landslide occurrence.

  13. The EP-3E vs. the BAMS UAS: An Operating and Support Cost Comparison

    DTIC Science & Technology

    2012-09-01

    Accountability Office HALE High Altitude Long Endurance ISR Intelligence, Surveillance and Reconnaissance JCC Joint Architecture...others are very complex high altitude long endurance (HALE) aircraft. However, most share the common need for satellite bandwidth. The DoD plan is...collection sites, and risks as they apply to the BAMS UAS. These factors were not adequately considered in the original O&S analysis . Once the analysis

  14. A Greenhouse Assay on the Effect of Applied Urea Amount on the Rhizospheric Soil Bacterial Communities.

    PubMed

    Shang, Shuanghua; Yi, Yanli

    2015-12-01

    The rhizospheric bacteria play key role in plant nutrition and growth promotion. The effects of increased nitrogen inputs on plant rhizospheric soils also have impacted on whole soil microbial communities. In this study, we analyzed the effects of applied nitrogen (urea) on rhizospheric bacterial composition and diversity in a greenhouse assay using the high-throughput sequencing technique. To explore the environmental factors driving the abundance, diversity and composition of soil bacterial communities, the relationship between soil variables and the bacterial communities were also analyzed using the mantel test as well as the redundancy analysis. The results revealed significant bacterial diversity changes at different amounts of applied urea, especially between the control treatment and the N fertilized treatments. Mantel tests showed that the bacterial communities were significantly correlated with the soil nitrate nitrogen, available nitrogen, soil pH, ammonium nitrogen and total organic carbon. The present study deepened the understanding about the rhizospheric soil microbial communities under different amounts of applied urea in greenhouse conditions, and our work revealed the environmental factors affecting the abundance, diversity and composition of rhizospheric bacterial communities.

  15. Measuring lexical diversity in narrative discourse of people with aphasia.

    PubMed

    Fergadiotis, Gerasimos; Wright, Heather H; West, Thomas M

    2013-05-01

    A microlinguistic content analysis for assessing lexical semantics in people with aphasia (PWA) is lexical diversity (LD). Sophisticated techniques have been developed to measure LD. However, validity evidence for these methodologies when applied to the discourse of PWA is lacking. The purpose of this study was to evaluate four measures of LD to determine how effective they were at measuring LD in PWA. Four measures of LD were applied to short discourse samples produced by 101 PWA: (a) the Measure of Textual Lexical Diversity (MTLD; McCarthy, 2005), (b) the Moving-Average Type-Token Ratio (MATTR; Covington, 2007), (c) D (McKee, Malvern, & Richards, 2000), and (d) the Hypergeometric Distribution (HD-D; McCarthy & Jarvis, 2007). LD was estimated using each method, and the scores were subjected to a series of analyses (e.g., curve-fitting, analysis of variance, confirmatory factor analysis). Results from the confirmatory factor analysis suggested that MTLD and MATTR reflect LD and little of anything else. Further, two indices (HD-D and D) were found to be equivalent, suggesting that either one can be used when samples are >50 tokens. MTLD and MATTR yielded the strongest evidence for producing unbiased LD scores, suggesting that they may be the best measures for capturing LD in PWA.

  16. Integrating community-based participatory research and informatics approaches to improve the engagement and health of underserved populations

    PubMed Central

    Schaefbauer, Chris L; Campbell, Terrance R; Senteio, Charles; Siek, Katie A; Bakken, Suzanne; Veinot, Tiffany C

    2016-01-01

    Objective We compare 5 health informatics research projects that applied community-based participatory research (CBPR) approaches with the goal of extending existing CBPR principles to address issues specific to health informatics research. Materials and methods We conducted a cross-case analysis of 5 diverse case studies with 1 common element: integration of CBPR approaches into health informatics research. After reviewing publications and other case-related materials, all coauthors engaged in collaborative discussions focused on CBPR. Researchers mapped each case to an existing CBPR framework, examined each case individually for success factors and barriers, and identified common patterns across cases. Results Benefits of applying CBPR approaches to health informatics research across the cases included the following: developing more relevant research with wider impact, greater engagement with diverse populations, improved internal validity, more rapid translation of research into action, and the development of people. Challenges of applying CBPR to health informatics research included requirements to develop strong, sustainable academic-community partnerships and mismatches related to cultural and temporal factors. Several technology-related challenges, including needs to define ownership of technology outputs and to build technical capacity with community partners, also emerged from our analysis. Finally, we created several principles that extended an existing CBPR framework to specifically address health informatics research requirements. Conclusions Our cross-case analysis yielded valuable insights regarding CBPR implementation in health informatics research and identified valuable lessons useful for future CBPR-based research. The benefits of applying CBPR approaches can be significant, particularly in engaging populations that are typically underserved by health care and in designing patient-facing technology. PMID:26228766

  17. Gender differences associated with enrollment in the Texas Academy of Mathematics and Science

    NASA Astrophysics Data System (ADS)

    Burns, Robert Thomas

    This study sought to determine if different factors had influenced females and males to select engineering/science-related studies at the Texas Academy of Mathematics and Science (TAMS). The data were collected in the fall semester in 1997 at TAMS located on the University of North Texas campus from a survey of factors reported in the literature that had influenced students to enroll in engineering/science-related curriculum. Of the 380 TAMS students enrolled fall semester, 303 or 85% participated in the study. Those who participated included 135 or 45% females and 168 or 55% males. A dichotomous discriminant function analysis to identify relationships between the criterion variable (gender) and the predictor variable (factors) was used. The analysis of variance (ANOVA) was used to identify any significant predictor (factor) when the criterion was gender. Analysis of the data indicated no difference between females and males concerning factors that influenced them to enroll in TAMS. Neither discriminant function analysis nor the regression analysis using weighted least squares could significantly establish any relationship that could predict a student to be female or male with respect to factors that influenced them to enroll in TAMS. The factors were ranked utilizing the Thurstone equal appearing intervals scale for both females and males. Both females and males in TAMS ranked extrinsic interest including job opportunity, salary, and promotion, as the most important factor. The least important factor for both females and males was family encouragement. The findings indicate that TAMS students based their enrollment decision on factors independent of those suggested in the literature as applying to males and females. This may have resulted from the fact that these students are a unique population biased toward valuing a math/science curriculum.

  18. Factors that influence career choice in primary care among medical students starting social service in Honduras.

    PubMed

    Puertas, E Benjamín; Rivera, Tamara Y

    2016-11-01

    To 1) describe patterns of specialty choice; 2) investigate relationships between career selection and selected demographic indicators; and 3) identify salary perception, factors that influence career choice in primary care, and factors that influence desired location of future medical practice. The study used a mixed-methods approach that included a cross-sectional questionnaire survey applied to 234 last-year medical students in Honduras (September 2014), and semi-structured interviews with eight key informants (October 2014). Statistical analysis included chi-square and factor analysis. An alpha level of 0.05 was used to determine significance. In the qualitative analysis, several codes were associated with each other, and five major themes emerged. Primary care careers were the preferred choice for 8.1% of students, who preferred urban settings for future practice location. The perceived salary of specialties other than primary care was significantly higher than those of general practitioners, family practitioners, and pediatricians (P < 0.001). Participants considered "making a difference," income, teaching, prestige, and challenging work the most important factors influencing career choice. Practice in ambulatory settings was significantly associated with a preference for primary care specialties (P = < 0.05). Logistic regression analysis found that factors related to patient-based care were statistically significant for selecting primary care (P = 0.006). The qualitative analysis further endorsed the survey findings, identifying additional factors that influence career choice (future work option; availability of residency positions; and social factors, including violence). Rationales behind preference of a specialty appeared to be based on a combination of ambition and prestige, and on personal and altruistic considerations. Most factors that influence primary care career choice are similar to those found in the literature. There are several factors distinctive to medical students in Honduras-most of them barriers to primary care career choice.

  19. Mean structure analysis from an IRT approach: an application in the context of organizational psychology.

    PubMed

    Revuelta Menéndez, Javier; Ximénez Gómez, Carmen

    2012-11-01

    The application of mean and covariance structure analysis with quantitative data is increasing. However, latent means analysis with qualitative data is not as widespread. This article summarizes the procedures to conduct an analysis of latent means of dichotomous data from an item response theory approach. We illustrate the implementation of these procedures in an empirical example referring to the organizational context, where a multi-group analysis was conducted to compare the latent means of three employee groups in two factors measuring personal preferences and the perceived degree of rewards from the organization. Results show that higher personal motivations are associated with higher perceived importance of the organization, and that these perceptions differ across groups, so that higher-level employees have a lower level of personal and perceived motivation. The article shows how to estimate the factor means and the factor correlation from dichotomous data, and how to assess goodness of fit. Lastly, we provide the M-Plus syntax code in order to facilitate the latent means analyses for applied researchers.

  20. DREEM on: validation of the Dundee Ready Education Environment Measure in Pakistan.

    PubMed

    Khan, Junaid Sarfraz; Tabasum, Saima; Yousafzai, Usman Khalil; Fatima, Mehreen

    2011-09-01

    To validate DREEM in medical education environment of Punjab, Pakistan. The DREEM questionnaire was anonymously collected from Final year Baccalaureate of Medicine; Baccalaureate of Surgery students in the private and public medical colleges affiliated with the University of Health Sciences, Lahore. Data was analyzed using Principal Component Analysis with Varimax Rotation. The response rate was 84.14 %. The average DREEM score was 125. Confirmatory and Exploratory Factor Analysis was applied under the conditions of eigenvalues >1 and loadings > or = 0.3. In CONFIRMATORY FACTOR ANALYSIS, Five components were extracted accounting for 40.10% of variance and in EXPLORATORY FACTOR ANALYSIS, Ten components were extracted accounting for 52.33% of variance. Total 50 items had internal consistency reliability of 0.91 (Cronbach's Alpha). The value of Spearman-Brown was 0.868 showing the reliability of the analysis. In both analyses the subscales produced were sensible but the mismatch from the original was largely due to the English-Pakistan contextual and cultural differences. DREEM is a generic instrument that will do well with regional modifications to suit individual, contextual and cultural settings.

  1. Emotional and tangible social support in a German population-based sample: Development and validation of the Brief Social Support Scale (BS6).

    PubMed

    Beutel, Manfred E; Brähler, Elmar; Wiltink, Jörg; Michal, Matthias; Klein, Eva M; Jünger, Claus; Wild, Philipp S; Münzel, Thomas; Blettner, Maria; Lackner, Karl; Nickels, Stefan; Tibubos, Ana N

    2017-01-01

    Aim of the study was the development and validation of the psychometric properties of a six-item bi-factorial instrument for the assessment of social support (emotional and tangible support) with a population-based sample. A cross-sectional data set of N = 15,010 participants enrolled in the Gutenberg Health Study (GHS) in 2007-2012 was divided in two sub-samples. The GHS is a population-based, prospective, observational single-center cohort study in the Rhein-Main-Region in western Mid-Germany. The first sub-sample was used for scale development by performing an exploratory factor analysis. In order to test construct validity, confirmatory factor analyses were run to compare the extracted bi-factorial model with the one-factor solution. Reliability of the scales was indicated by calculating internal consistency. External validity was tested by investigating demographic characteristics health behavior, and distress using analysis of variance, Spearman and Pearson correlation analysis, and logistic regression analysis. Based on an exploratory factor analysis, a set of six items was extracted representing two independent factors. The two-factor structure of the Brief Social Support Scale (BS6) was confirmed by the results of the confirmatory factor analyses. Fit indices of the bi-factorial model were good and better compared to the one-factor solution. External validity was demonstrated for the BS6. The BS6 is a reliable and valid short scale that can be applied in social surveys due to its brevity to assess emotional and practical dimensions of social support.

  2. The application of subset correspondence analysis to address the problem of missing data in a study on asthma severity in childhood.

    PubMed

    Hendry, G; North, D; Zewotir, T; Naidoo, R N

    2014-09-28

    Non-response in cross-sectional data is not uncommon and requires careful handling during the analysis stage so as not to bias results. In this paper, we illustrate how subset correspondence analysis can be applied in order to manage the non-response while at the same time retaining all observed data. This variant of correspondence analysis was applied to a set of epidemiological data in which relationships between numerous environmental, genetic, behavioural and socio-economic factors and their association with asthma severity in children were explored. The application of subset correspondence analysis revealed interesting associations between the measured variables that otherwise may not have been exposed. Many of the associations found confirm established theories found in literature regarding factors that exacerbate childhood asthma. Moderate to severe asthma was found to be associated with needing neonatal care, male children, 8- to 9-year olds, exposure to tobacco smoke in vehicles and living in areas that suffer from extreme air pollution. Associations were found between mild persistent asthma and low birthweight, and being exposed to smoke in the home and living in a home with up to four people. The classification of probable asthma was associated with a group of variables that indicate low socio-economic status. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Cement Leakage in Percutaneous Vertebral Augmentation for Osteoporotic Vertebral Compression Fractures: Analysis of Risk Factors.

    PubMed

    Xie, Weixing; Jin, Daxiang; Ma, Hui; Ding, Jinyong; Xu, Jixi; Zhang, Shuncong; Liang, De

    2016-05-01

    The risk factors for cement leakage were retrospectively reviewed in 192 patients who underwent percutaneous vertebral augmentation (PVA). To discuss the factors related to the cement leakage in PVA procedure for the treatment of osteoporotic vertebral compression fractures. PVA is widely applied for the treatment of osteoporotic vertebral fractures. Cement leakage is a major complication of this procedure. The risk factors for cement leakage were controversial. A retrospective review of 192 patients who underwent PVA was conducted. The following data were recorded: age, sex, bone density, number of fractured vertebrae before surgery, number of treated vertebrae, severity of the treated vertebrae, operative approach, volume of injected bone cement, preoperative vertebral compression ratio, preoperative local kyphosis angle, intraosseous clefts, preoperative vertebral cortical bone defect, and ratio and type of cement leakage. To study the correlation between each factor and cement leakage ratio, bivariate regression analysis was employed to perform univariate analysis, whereas multivariate linear regression analysis was employed to perform multivariate analysis. The study included 192 patients (282 treated vertebrae), and cement leakage occurred in 100 vertebrae (35.46%). The vertebrae with preoperative cortical bone defects generally exhibited higher cement leakage ratio, and the leakage is typically type C. Vertebrae with intact cortical bones before the procedure tend to experience type S leakage. Univariate analysis showed that patient age, bone density, number of fractured vertebrae before surgery, and vertebral cortical bone were associated with cement leakage ratio (P<0.05). Multivariate analysis showed that the main factors influencing bone cement leakage are bone density and vertebral cortical bone defect, with standardized partial regression coefficients of -0.085 and 0.144, respectively. High bone density and vertebral cortical bone defect are independent risk factors associated with bone cement leakage.

  4. R/S analysis of reaction time in Neuron Type Test for human activity in civil aviation

    NASA Astrophysics Data System (ADS)

    Zhang, Hong-Yan; Kang, Ming-Cui; Li, Jing-Qiang; Liu, Hai-Tao

    2017-03-01

    Human factors become the most serious problem leading to accidents of civil aviation, which stimulates the design and analysis of Neuron Type Test (NTT) system to explore the intrinsic properties and patterns behind the behaviors of professionals and students in civil aviation. In the experiment, normal practitioners' reaction time sequences, collected from NTT, exhibit log-normal distribution approximately. We apply the χ2 test to compute the goodness-of-fit by transforming the time sequence with Box-Cox transformation to cluster practitioners. The long-term correlation of different individual practitioner's time sequence is represented by the Hurst exponent via Rescaled Range Analysis, also named by Range/Standard deviation (R/S) Analysis. The different Hurst exponent suggests the existence of different collective behavior and different intrinsic patterns of human factors in civil aviation.

  5. [Application of risk-based approach for determination of critical factors in technology transfer of production of medicinal products].

    PubMed

    Beregovykh, V V; Spitskiy, O R

    2014-01-01

    Risk-based approach is used for examination of impact of different factors on quality of medicinal products in technology transfer. A general diagram is offered for risk analysis execution in technology transfer from pharmaceutical development to production. When transferring technology to full- scale commercial production it is necessary to investigate and simulate production process application beforehand in new real conditions. The manufacturing process is the core factorfor risk analysis having the most impact on quality attributes of a medicinal product. Further importantfactors are linked to materials and products to be handled and manufacturing environmental conditions such as premises, equipment and personnel. Usage of risk-based approach in designing of multipurpose production facility of medicinal products is shown where quantitative risk analysis tool RAMM (Risk Analysis and Mitigation Matrix) was applied.

  6. The parameters effect on the structural performance of damaged steel box beam using Taguchi method

    NASA Astrophysics Data System (ADS)

    El-taly, Boshra A.; Abd El Hameed, Mohamed F.

    2018-03-01

    In the current study, the influence of notch or opening parameters and the positions of the applied load on the structural performance of steel box beams up to failure was investigated using Finite Element analysis program, ANSYS. The Taguchi-based design of experiments technique was used to plan the current study. The plan included 12 box steel beams; three intact beams, and nine damaged beams (with opening) in the beams web. The numerical studies were conducted under varying the spacing between the two concentrated point loads (location of applied loads), the notch (opening) position, and the ratio between depth and width of the notch with a constant notch area. According to Taguchi analysis, factor X (location of the applied loads) was found the highest contributing parameters for the variation of the ultimate load, vertical deformation, shear stresses, and the compressive normal stresses.

  7. Preparation of Artificial Skin that Mimics Human Skin Surface and Mechanical Properties.

    PubMed

    Shimizu, Rana; Nonomura, Yoshimune

    2018-01-01

    We have developed an artificial skin that mimics the morphological and mechanical properties of human skin. The artificial skin comprises a polyurethane block possessing a microscopically rough surface. We evaluated the tactile sensations when skin-care cream was applied to the artificial skin. Many subjects perceived smooth, moist, and soft feels during the application process. Cluster analysis showed that these characteristic tactile feels are similar to those when skin-care cream is applied to real human skin. Contact angle analysis showed that an oil droplet spread smoothly on the artificial skin surface, which occurred because there were many grooves several hundred micrometers in width on the skin surface. In addition, when the skin-care cream was applied, the change in frictional force during the dynamic friction process increased. These wetting and frictional properties are important factors controlling the similarity of artificial skin to real human skin.

  8. Proposal of a service delivery integration index of home care for older persons: application in several European cities

    PubMed Central

    Henrard, Jean-Claude; Ankri, Joël; Frijters, Dinnus; Carpenter, Iain; Topinkova, Eva; Garms-Homolova, Vjenka; Finne-Soveri, Harriett; Sørbye, Liv Wergeland; Jónsson, Palmi V.; Ljunggren, Gunnar; Schroll, Marianne; Wagner, Cordula; Bernabei, Roberto

    2006-01-01

    Abstract Purpose To propose an integration index of home care delivery to older persons, to study its validity and to apply it to home care services of European cities. Theory Home care delivery integration was based on two dimensions referring to process-centred integration and organisational structure approach. Method Items considered as part of both dimensions according to an expert consensus (face validity) were extracted from a standardised questionnaire used in “Aged in Home care” (AdHoc) study to capture basic characteristics of home care services. Their summation leads to a services' delivery integration index. This index was applied to AdHoc services. A factor analysis was computed in order to empirically test the validity of the theoretical constructs. The plot of the settings was performed. Results Application of the index ranks home care services in four groups according to their score. Factor analysis identifies a first factor which opposes working arrangement within service to organisational structure bringing together provisions for social care. A second factor corresponds to basic nursing care and therapies. Internal consistency for those three domains ranges from 0.78 to 0.93. When plotting the different settings different models of service delivery appear. Conclusion The proposed index shows that behind a total score several models of care delivery are hidden. Comparison of service delivery integration should take into account this heterogeneity. PMID:17006549

  9. Spanish adaptation of the revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R).

    PubMed

    Campos, Teresa Salas; Rodríguez-Santos, Francisco; Esteban, Jesus; Vázquez, Pilar Cordero; Mora Pardina, Jesus S; Carmona, Alejandra Cano

    2010-10-01

    ALSFRS-R is a tool designed to measure disease progress in ALS patients. It consists of 12 items grouped into four functions designed to assess disabilities according to the Activities of daily living (ADL). Our objective was to validate the Spanish version of ALSFRS-R based on the original version. Four examiners assessed 73 ALS patients, applying the ALSFRS-R, ALSAQ-40 and the respiratory function variable assessed by the SRI scale, which measures respiratory insufficiency. Internal consistency and test-retest correlations were measured using Cronbach's alpha and Spearman's Rho tests. Factor analysis was performed by applying Varimax rotation and Kaiser standardization. Validity was analysed based on correlations between items in the ALSFRS-R scales and equivalents in the ALSAQ-40 and SRI questionnaires. The results showed high internal consistency (0.77-0.95) and a good test-retest correlation (0.80-0.95). Factor analysis showed a 73.3% principal component contribution; the weight of each item regarding their corresponding factors was 0.7-0.9. High correlations were observed (rs >0.60) between corresponding factors of ALSFRS-R/ALSAQ-40 and ALSFRS-R/SRI. We conclude that the version obtained from the ALSFRS-R maintains the internal consistency and validity of the construct of the original scale. The Spanish version of ALSFRS-R is available for readers at http://www.fundela.es/verOtras.php.

  10. Two-way and three-way approaches to ultra high performance liquid chromatography-photodiode array dataset for the quantitative resolution of a two-component mixture containing ciprofloxacin and ornidazole.

    PubMed

    Dinç, Erdal; Ertekin, Zehra Ceren; Büker, Eda

    2016-09-01

    Two-way and three-way calibration models were applied to ultra high performance liquid chromatography with photodiode array data with coeluted peaks in the same wavelength and time regions for the simultaneous quantitation of ciprofloxacin and ornidazole in tablets. The chromatographic data cube (tensor) was obtained by recording chromatographic spectra of the standard and sample solutions containing ciprofloxacin and ornidazole with sulfadiazine as an internal standard as a function of time and wavelength. Parallel factor analysis and trilinear partial least squares were used as three-way calibrations for the decomposition of the tensor, whereas three-way unfolded partial least squares was applied as a two-way calibration to the unfolded dataset obtained from the data array of ultra high performance liquid chromatography with photodiode array detection. The validity and ability of two-way and three-way analysis methods were tested by analyzing validation samples: synthetic mixture, interday and intraday samples, and standard addition samples. Results obtained from two-way and three-way calibrations were compared to those provided by traditional ultra high performance liquid chromatography. The proposed methods, parallel factor analysis, trilinear partial least squares, unfolded partial least squares, and traditional ultra high performance liquid chromatography were successfully applied to the quantitative estimation of the solid dosage form containing ciprofloxacin and ornidazole. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. GPs' considerations in multimorbidity management: a qualitative study.

    PubMed

    Luijks, Hilde D; Loeffen, Maartje J W; Lagro-Janssen, Antoine L; van Weel, Chris; Lucassen, Peter L; Schermer, Tjard R

    2012-07-01

    Scientific evidence on how to manage multimorbidity is limited, but GPs have extensive practical experience with multimorbidity management. To explore GPs' considerations and main objectives in the management of multimorbidity and to explore factors influencing their management of multimorbidity. Focus group study of Dutch GPs; with heterogeneity in characteristics such as sex, age and urbanisation. The moderator used an interview guide in conducting the interviews. Two researchers performed the analysis as an iterative process, based on verbatim transcripts and by applying the technique of constant comparative analysis. Data collection proceeded until saturation was reached. Five focus groups were conducted with 25 participating GPs. The main themes concerning multimorbidity management were individualisation, applying an integrated approach, medical considerations placed in perspective, and sharing decision making and responsibility. A personal patient-doctor relationship was considered a major factor positively influencing the management of multimorbidity. Mental-health problems and interacting conditions were regarded as major barriers in this respect and participants experienced several practical problems. The concept of patient-centredness overarches the participants' main objectives. GPs' main objective in multimorbidity management is applying a patient-centred approach. This approach is welcomed since it counteracts some potential pitfalls of multimorbidity. Further research should include a similar design in a different setting and should aim at developing best practice in multimorbidity management.

  12. Quantifying the Strength of General Factors in Psychopathology: A Comparison of CFA with Maximum Likelihood Estimation, BSEM, and ESEM/EFA Bifactor Approaches.

    PubMed

    Murray, Aja Louise; Booth, Tom; Eisner, Manuel; Obsuth, Ingrid; Ribeaud, Denis

    2018-05-22

    Whether or not importance should be placed on an all-encompassing general factor of psychopathology (or p factor) in classifying, researching, diagnosing, and treating psychiatric disorders depends (among other issues) on the extent to which comorbidity is symptom-general rather than staying largely within the confines of narrower transdiagnostic factors such as internalizing and externalizing. In this study, we compared three methods of estimating p factor strength. We compared omega hierarchical and explained common variance calculated from confirmatory factor analysis (CFA) bifactor models with maximum likelihood (ML) estimation, from exploratory structural equation modeling/exploratory factor analysis models with a bifactor rotation, and from Bayesian structural equation modeling (BSEM) bifactor models. Our simulation results suggested that BSEM with small variance priors on secondary loadings might be the preferred option. However, CFA with ML also performed well provided secondary loadings were modeled. We provide two empirical examples of applying the three methodologies using a normative sample of youth (z-proso, n = 1,286) and a university counseling sample (n = 359).

  13. Junior College Faculty Job Satisfaction.

    ERIC Educational Resources Information Center

    Frankel, Joanne

    Some of the research done to date concerning job satisfaction of junior college faculty is reviewed in this "Brief." Part I of the "Brief" describes four frameworks that have been applied to the analysis of job satisfaction: the traditional approach, the two-factor approach, the need hierarchy, and the cognitive dissonance approach. Part II…

  14. A Typology of Students Based on Academic Entitlement

    ERIC Educational Resources Information Center

    Luckett, Michael; Trocchia, Philip J.; Noel, Noel Mark; Marlin, Dan

    2017-01-01

    Two hundred ninety-three university business students were surveyed using an academic entitlement (AE) scale updated to include new technologies. Using factor analysis, three components of AE were identified: grade entitlement, behavioral entitlement, and service entitlement. A k-means clustering procedure was then applied to identify four groups…

  15. Observations on Substance Abuse Theory.

    ERIC Educational Resources Information Center

    Shaffer, Howard J.

    1986-01-01

    Applies a philosophy of science perspective to substance abuse theory to clarify these theories in general and peer cluster theory in particular. Examines the natural history of an illicit drug from a macroscopic level of analysis to illuminate some of the social-psychological factors that influence drug use and abuse patterns. (Author/KS)

  16. Community College Recruitment: An Analysis of Applicant Reactions.

    ERIC Educational Resources Information Center

    Winter, Paul A.; Kjorlien, Chad L.

    The purpose of this study was to: (1) conduct an empirical examination of applicant reactions to faculty jobs described in recruitment advertisements for business faculty vacancies at community colleges; and (2) assess factors that potentially impact applicant decisions to apply for and pursue position vacancies. The results of this study have…

  17. A Factor Analytic Validation of Holland's Vocational Preference Inventory

    ERIC Educational Resources Information Center

    Di Scipio, William J.

    1974-01-01

    A principal components analysis was applied to a 135-item pool of the Holland Vocational Preference Inventory, Sixth Revision. The a priori clinical scales were partially upheld with differences attributed to the characteristics of the sample and sociopolitical time context during which the test was administered. (Author)

  18. Job Attitudes among Different Occupational Status Groups. An Economic Analysis.

    ERIC Educational Resources Information Center

    Ronen, Simcha; Sadan, Simcha

    1984-01-01

    An economic model is applied to employee attitudinal variables to compare the contribution of intrinsic and extrinsic factors to job satisfaction for skilled workers and managers in an electronics manufacturing organization. Intrinsic rewards are found to increase in importance as employment level increases, suggesting different frames of…

  19. AN ALTERNATIVE METHOD FOR ESTABLISHING TEFS FOR DIOXIN-LIKE COMPOUNDS. PART 1. EVALUATION OF DECISION ANALYSIS METHODS FOR USE IN WEIGHTING RELATIVE POTENCY DATA

    EPA Science Inventory

    A number of investigators have recently examined the utility of applying probabilistic techniques in the derivation of toxic equivalency factors (TEFs) for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (...

  20. Strainrange partitioning behavior of an automotive turbine alloy

    NASA Technical Reports Server (NTRS)

    Annis, C. G.; Vanwanderham, M. C.; Wallace, R. M.

    1976-01-01

    This report addresses Strainrange Partitioning, an advanced life prediction analysis procedure, as applied to CA-101 (cast IN 792 + Hf), an alloy proposed for turbine disks in automotive gas turbine engines. The methodology was successful in predicting specimen life under thermal-mechanical cycling, to within a factor of + or - 2.

  1. Relationship between Russian wheat aphid abundance and edaphic and topographic characteristics of wheat fields

    USDA-ARS?s Scientific Manuscript database

    This study explores the spatial relationship between Russian wheat aphid population density and variation in edaphic or topographic factors within wheat fields. Multiple regression analysis was applied to data collected from six wheat fields located in three States, Colorado, Wyoming, and Nebraska....

  2. ANALYSIS OF LOW-LEVEL PESTICIDES FROM HIGH-ELEVATION LAKE WATERS BY LARGE-VOLUME INJECTION GCMS

    EPA Science Inventory

    Pesticides are among the factors being proposed as causal agents for amphibian population declines in the Sierra Nevada range of California, USA. We hypothesize that agricultural pesticides applied in the San Joaquin Valley west of the mountains are volatilized or eroded, transpo...

  3. [Assessment of psychometric properties of the academic involvement questionnaire, expectations version].

    PubMed

    Pérez V, Cristhian; Ortiz M, Liliana; Fasce H, Eduardo; Parra P, Paula; Matus B, Olga; McColl C, Peter; Torres A, Graciela; Meyer K, Andrea; Márquez U, Carolina; Ortega B, Javiera

    2015-11-01

    Academic Involvement Questionnaire, Expectations version (CIA-A), assesses the expectations of involvement in studies. It is a relevant predictor of student success. However, the evidence of its validity and reliability in Chile is low, and in the case of Medical students, there is no evidence at all. To evaluate the factorial structure and internal consistency of the CIA-A in Chilean Medical school freshmen. The survey was applied to 340 Medicine freshmen, chosen by non-probability quota sampling. They answered a back-translated version of CIA-A from Portuguese to Spanish, plus a sociodemographic questionnaire. For psychometric analysis of the CIA-A, an exploratory factor analysis was carried on, the reliability of the factors was calculated, a descriptive analysis was conducted and their correlation was assessed. Five factors were identified: vocational, institutional and social involvement, use of resources and student participation. Their reliabilities ranged between Cronbach's alpha values of 0.71 to 0.87. Factors also showed statistically significant correlations between each other. Identified factor structure is theoretically consistent with the structure of original version. It just disagrees in one factor. In addition, the factors' internal consistency were adequate for using them in research. This supports the construct validity and reliability of the CIA-A to assess involvement expectations in medical school freshmen.

  4. Assessment of groundwater vulnerability to pollution: a combination of GIS, fuzzy logic and decision making techniques

    NASA Astrophysics Data System (ADS)

    Gemitzi, Alexandra; Petalas, Christos; Tsihrintzis, Vassilios A.; Pisinaras, Vassilios

    2006-03-01

    The assessment of groundwater vulnerability to pollution aims at highlighting areas at a high risk of being polluted. This study presents a methodology, to estimate the risk of an aquifer to be polluted from concentrated and/or dispersed sources, which applies an overlay and index method involving several parameters. The parameters are categorized into three factor groups: factor group 1 includes parameters relevant to the internal aquifer system’s properties, thus determining the intrinsic aquifer vulnerability to pollution; factor group 2 comprises parameters relevant to the external stresses to the system, such as human activities and rainfall effects; factor group 3 incorporates specific geological settings, such as the presence of geothermal fields or salt intrusion zones, into the computation process. Geographical information systems have been used for data acquisition and processing, coupled with a multicriteria evaluation technique enhanced with fuzzy factor standardization. Moreover, besides assigning weights to factors, a second set of weights, i.e., order weights, has been applied to factors on a pixel by pixel basis, thus allowing control of the level of risk in the vulnerability determination and the enhancement of local site characteristics. Individual analysis of each factor group resulted in three intermediate groundwater vulnerability to pollution maps, which were combined in order to produce the final composite groundwater vulnerability map for the study area. The method has been applied in the region of Eastern Macedonia and Thrace (Northern Greece), an area of approximately 14,000 km2. The methodology has been tested and calibrated against the measured nitrate concentration in wells, in the northwest part of the study area, providing results related to the aggregation and weighting procedure.

  5. AASC Recommendations for the Education of an Applied Climatologist

    NASA Astrophysics Data System (ADS)

    Nielsen-Gammon, J. W.; Stooksbury, D.; Akyuz, A.; Dupigny-Giroux, L.; Hubbard, K. G.; Timofeyeva, M. M.

    2011-12-01

    The American Association of State Climatologists (AASC) has developed curricular recommendations for the education of future applied and service climatologists. The AASC was founded in 1976. Membership of the AASC includes state climatologists and others who work in state climate offices; climate researchers in academia and educators; applied climatologists in NOAA and other federal agencies; and the private sector. The AASC is the only professional organization dedicated solely to the growth and development of applied and service climatology. The purpose of the recommendations is to offer a framework for existing and developing academic climatology programs. These recommendations are intended to serve as a road map and to help distinguish the educational needs for future applied climatologists from those of operational meteorologists or other scientists and practitioners. While the home department of climatology students may differ from one program to the next, the most essential factor is that students can demonstrate a breadth and depth of understanding in the knowledge and tools needed to be an applied climatologist. Because the training of an applied climatologist requires significant depth and breadth, the Masters degree is recommended as the minimum level of education needed. This presentation will highlight the AASC recommendations. These include a strong foundation in: - climatology (instrumentation and data collection, climate dynamics, physical climatology, synoptic and regional climatology, applied climatology, climate models, etc.) - basic natural sciences and mathematics including calculus, physics, chemistry, and biology/ecology - fundamental atmospheric sciences (atmospheric dynamics, atmospheric thermodynamics, atmospheric radiation, and weather analysis/synoptic meteorology) and - data analysis and spatial analysis (descriptive statistics, statistical methods, multivariate statistics, geostatistics, GIS, etc.). The recommendations also include a secondary area of concentration (agriculture, economics, geography, hydrology, marine sciences, natural resources, policy, etc.) and a major applied climate research component.

  6. The self-transcendence scale: an investigation of the factor structure among nursing home patients.

    PubMed

    Haugan, Gørill; Rannestad, Toril; Garåsen, Helge; Hammervold, Randi; Espnes, Geir Arild

    2012-09-01

    Self-transcendence, the ability to expand personal boundaries in multiple ways, has been found to provide well-being. The purpose of this study was to examine the dimensionality of the Norwegian version of the Self-Transcendence Scale, which comprises 15 items. Reed's empirical nursing theory of self-transcendence provided the theoretical framework; self-transcendence includes an interpersonal, intrapersonal, transpersonal, and temporal dimension. Cross-sectional data were obtained from a sample of 202 cognitively intact elderly patients in 44 Norwegian nursing homes. Exploratory factor analysis revealed two and four internally consistent dimensions of self-transcendence, explaining 35.3% (two factors) and 50.7% (four factors) of the variance, respectively. Confirmatory factor analysis indicated that the hypothesized two- and four-factor models fitted better than the one-factor model (cx (2), root mean square error of approximation, standardized root mean square residual, normed fit index, nonnormed fit index, comparative fit index, goodness-of-fit index, and adjusted goodness-of-fit index). The findings indicate self-transcendence as a multifactorial construct; at present, we conclude that the two-factor model might be the most accurate and reasonable measure of self-transcendence. This research generates insights in the application of the widely used Self-Transcendence Scale by investigating its psychometric properties by applying a confirmatory factor analysis. It also generates new research-questions on the associations between self-transcendence and well-being.

  7. Multigroup confirmatory factor analysis and structural invariance with age of the Behavior Rating Inventory of Executive Function (BRIEF)--French version.

    PubMed

    Fournet, Nathalie; Roulin, Jean-Luc; Monnier, Catherine; Atzeni, Thierry; Cosnefroy, Olivier; Le Gall, Didier; Roy, Arnaud

    2015-01-01

    The parent and teacher forms of the French version of the Behavioral Rating Inventory of Executive Function (BRIEF) were used to evaluate executive function in everyday life in a large sample of healthy children (N = 951) aged between 5 and 18. Several psychometric methods were applied, with a view to providing clinicians with tools for score interpretation. The parent and teacher forms of the BRIEF were acceptably reliable. Demographic variables (such as age and gender) were found to influence the BRIEF scores. Confirmatory factor analysis was then used to test five competing models of the BRIEF's latent structure. Two of these models (a three-factor model and a two-factor model, both based on a nine-scale structure) had a good fit. However, structural invariance with age was only obtained with the two-factor model. The French version of the BRIEF provides a useful measure of everyday executive function and can be recommended for use in clinical research and practice.

  8. Sensory factors affecting female consumers' acceptability of nail polish.

    PubMed

    Sun, C; Koppel, K; Adhikari, K

    2015-12-01

    The objectives of this study were to determine what sensory factors impact consumers' acceptability of nail polishes, to explore how these sensory factors impact consumers' acceptability of nail polishes, to investigate whether there are any consumer segments according to their overall acceptability on different nail polishes and to scrutinize how the consumer segments are related to the sensory factors. Ninety-eight females participated in a nail polish consumer study at Kansas State University. Eight commercial products belonging to four categories - regular (REG), gel (GEL), flake (FLK) and water-based (WAT) - were evaluated. Each nail polish sample was evaluated twice by each participant in two different tasks - a task devoted to applying and evaluating the product and a task devoted to observing the appearance and evaluating the product. Pearson's correlation analysis, analysis of variance (ANOVA), external preference mapping, cluster analysis and internal preference mapping were applied for data analysis. Participants' scores of overall liking of the nail polishes were similar in the application task and in the observation task. In general, participants liked the REG and GEL product samples more than the FLK and WAT samples. Among all the sensory attributes, appearance attributes were the major factors that affected participants' overall liking. Aroma seemed to be a minor factor to participants' overall liking. Some sensory attributes, such as runny, shininess, opacity, spreadability, smoothness, coverage and wet appearance, were found to drive participants' overall acceptability positively, whereas others such as pinhole, fatty-edges, blister, brushlines, pearl-like, flake-protrusion, glittery and initial-drag impacted participants' overall acceptability negatively. Four clusters of participants were identified according to their overall liking scores from both the application task and the observation task. Participants' acceptability, based on different sensory attributes, could help a nail polish manufacturer modify or improve their nail polish formulas. Nail polish manufacturers could use the consumer cluster information to improve their marketing strategies for specific categories of their products and to target their advertising on particular consumer groups. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  9. Bayesian inference of the number of factors in gene-expression analysis: application to human virus challenge studies.

    PubMed

    Chen, Bo; Chen, Minhua; Paisley, John; Zaas, Aimee; Woods, Christopher; Ginsburg, Geoffrey S; Hero, Alfred; Lucas, Joseph; Dunson, David; Carin, Lawrence

    2010-11-09

    Nonparametric Bayesian techniques have been developed recently to extend the sophistication of factor models, allowing one to infer the number of appropriate factors from the observed data. We consider such techniques for sparse factor analysis, with application to gene-expression data from three virus challenge studies. Particular attention is placed on employing the Beta Process (BP), the Indian Buffet Process (IBP), and related sparseness-promoting techniques to infer a proper number of factors. The posterior density function on the model parameters is computed using Gibbs sampling and variational Bayesian (VB) analysis. Time-evolving gene-expression data are considered for respiratory syncytial virus (RSV), Rhino virus, and influenza, using blood samples from healthy human subjects. These data were acquired in three challenge studies, each executed after receiving institutional review board (IRB) approval from Duke University. Comparisons are made between several alternative means of per-forming nonparametric factor analysis on these data, with comparisons as well to sparse-PCA and Penalized Matrix Decomposition (PMD), closely related non-Bayesian approaches. Applying the Beta Process to the factor scores, or to the singular values of a pseudo-SVD construction, the proposed algorithms infer the number of factors in gene-expression data. For real data the "true" number of factors is unknown; in our simulations we consider a range of noise variances, and the proposed Bayesian models inferred the number of factors accurately relative to other methods in the literature, such as sparse-PCA and PMD. We have also identified a "pan-viral" factor of importance for each of the three viruses considered in this study. We have identified a set of genes associated with this pan-viral factor, of interest for early detection of such viruses based upon the host response, as quantified via gene-expression data.

  10. A Method for Thermal Analysis of Spiral Bevel Gears

    NASA Technical Reports Server (NTRS)

    Handschuh, Robert F.; Kicher, Thomas P.

    1994-01-01

    A modeling method for analyzing the three-dimensional thermal behavior of spiral bevel gears has been developed. The model surfaces are generated through application of differential geometry to the manufacturing process for face-milled spiral bevel gears. Contact on the gear surface is found by combining tooth contact analysis with three-dimensional Hertzian theory. The tooth contact analysis provides the principle curvatures and orientations of the two surfaces. This information is then used directly in the Hertzian analysis to find the contact size and maximum pressure. Heat generation during meshing is determined as a function of the applied load, sliding velocity, and coefficient of friction. Each of these factors change as the point of contact changes during meshing. A nonlinear finite element program was used to conduct the heat transfer analysis. This program permitted the time- and position-varying boundary conditions, found in operation, to be applied to a one-tooth model. An example model and analytical results are presented.

  11. A Time Series Analysis: Weather Factors, Human Migration and Malaria Cases in Endemic Area of Purworejo, Indonesia, 2005–2014

    PubMed Central

    REJEKI, Dwi Sarwani Sri; NURHAYATI, Nunung; AJI, Budi; MURHANDARWATI, E. Elsa Herdiana; KUSNANTO, Hari

    2018-01-01

    Background: Climatic and weather factors become important determinants of vector-borne diseases transmission like malaria. This study aimed to prove relationships between weather factors with considering human migration and previous case findings and malaria cases in endemic areas in Purworejo during 2005–2014. Methods: This study employed ecological time series analysis by using monthly data. The independent variables were the maximum temperature, minimum temperature, maximum humidity, minimum humidity, precipitation, human migration, and previous malaria cases, while the dependent variable was positive malaria cases. Three models of count data regression analysis i.e. Poisson model, quasi-Poisson model, and negative binomial model were applied to measure the relationship. The least Akaike Information Criteria (AIC) value was also performed to find the best model. Negative binomial regression analysis was considered as the best model. Results: The model showed that humidity (lag 2), precipitation (lag 3), precipitation (lag 12), migration (lag1) and previous malaria cases (lag 12) had a significant relationship with malaria cases. Conclusion: Weather, migration and previous malaria cases factors need to be considered as prominent indicators for the increase of malaria case projection. PMID:29900134

  12. Sensitivity analysis of navy aviation readiness based sparing model

    DTIC Science & Technology

    2017-09-01

    variability. (See Figure 4.) Figure 4. Research design flowchart 18 Figure 4 lays out the four steps of the methodology , starting in the upper left-hand...as a function of changes in key inputs. We develop NAVARM Experimental Designs (NED), a computational tool created by applying a state-of-the-art...experimental design to the NAVARM model. Statistical analysis of the resulting data identifies the most influential cost factors. Those are, in order of

  13. Broadband Studies of Semsmic Sources at Regional and Teleseismic Distances Using Advanced Time Series Analysis Methods. Volume 1.

    DTIC Science & Technology

    1991-03-21

    discussion of spectral factorability and motivations for broadband analysis, the report is subdivided into four main sections. In Section 1.0, we...estimates. The motivation for developing our multi-channel deconvolution method was to gain information about seismic sources, most notably, nuclear...with complex constraints for estimating the rupture history. Such methods (applied mostly to data sets that also include strong rmotion data), were

  14. Confirmatory factor analysis for two questionnaires of caregiving in eating disorders

    PubMed Central

    Hibbs, Rebecca; Rhind, Charlotte; Sallis, Hannah; Goddard, Elizabeth; Raenker, Simone; Ayton, Agnes; Bamford, Bryony; Arcelus, Jon; Boughton, Nicky; Connan, Frances; Goss, Ken; Lazlo, Bert; Morgan, John; Moore, Kim; Robertson, David; Schreiber-Kounine, Christa; Sharma, Sonu; Whitehead, Linette; Lacey, Hubert; Schmidt, Ulrike; Treasure, Janet

    2014-01-01

    Objective: Caring for someone diagnosed with an eating disorder (ED) is associated with a high level of burden and psychological distress which can inadvertently contribute to the maintenance of the illness. The Eating Disorders Symptom Impact Scale (EDSIS) and Accommodation and Enabling Scale for Eating Disorders (AESED) are self-report scales to assess elements of caregiving theorised to contribute to the maintenance of an ED. Further validation and confirmation of the factor structures for these scales are necessary for rigorous evaluation of complex interventions which target these modifiable elements of caregiving. Method: EDSIS and AESED data from 268 carers of people with anorexia nervosa (AN), recruited from consecutive admissions to 15 UK inpatient or day patient hospital units, were subjected to confirmatory factor analysis to test model fit by applying the existing factor structures: (a) four-factor structure for the EDSIS and (b) five-factor structure for the AESED. Results: Confirmatory factor analytic results support the existing four-factor and five-factor structures for the EDSIS and the AESED, respectively. Discussion: The present findings provide further validation of the EDSIS and the AESED as tools to assess modifiable elements of caregiving for someone with an ED. PMID:25750785

  15. Structural validity of the Maslach Burnout Inventory and influence of depressive symptoms in banking workplace: Unfastening the occupational conundrum.

    PubMed

    Valente, Maria do Socorro da Silva; Wang, Yuan-Pang; Menezes, Paulo Rossi

    2018-06-04

    Burnout and mental disorders have been reported in the financial industry. This study aims to examine the structural validity of the Maslach Burnout Inventory (MBI) and to investigate the connection between the dimensions of burnout and depressive symptoms in a sample of 1046 bank employees from North Brazil who completed the MBI and the Patient Health Questionnaire-9 (PHQ-9. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to cross-check the factorial structure of the MBI. One-way analysis of variance and correlation analysis were applied to elucidate the relationship between burnout and depressive symptoms. Both 3-factor and 4-factor oblique solutions were plausible EFA models of the burnout syndrome. Results of CFA supported the 19-item 4-factor structure as the best fitting model to data, with two exhaustion factors ("exhausted" and "strained"), depersonalization, and personal accomplishment. The PHQ-9 total score and individual score of depressive items were significantly correlated with all MBI dimensions, notably with the emotional exhaustion dimension. The moderate-to-high correlation observed between burnout and depression suggest the potential utility of the MBI for evaluating burnout among bank employees as well as to point out the need to evaluate systematically the burnout and depressive symptoms given to their potential association. Copyright © 2018. Published by Elsevier B.V.

  16. Vibroacoustic optimization using a statistical energy analysis model

    NASA Astrophysics Data System (ADS)

    Culla, Antonio; D`Ambrogio, Walter; Fregolent, Annalisa; Milana, Silvia

    2016-08-01

    In this paper, an optimization technique for medium-high frequency dynamic problems based on Statistical Energy Analysis (SEA) method is presented. Using a SEA model, the subsystem energies are controlled by internal loss factors (ILF) and coupling loss factors (CLF), which in turn depend on the physical parameters of the subsystems. A preliminary sensitivity analysis of subsystem energy to CLF's is performed to select CLF's that are most effective on subsystem energies. Since the injected power depends not only on the external loads but on the physical parameters of the subsystems as well, it must be taken into account under certain conditions. This is accomplished in the optimization procedure, where approximate relationships between CLF's, injected power and physical parameters are derived. The approach is applied on a typical aeronautical structure: the cabin of a helicopter.

  17. Decision making tools for selecting sustainable wastewater treatment technologies in Thailand

    NASA Astrophysics Data System (ADS)

    Wongburi, Praewa; Park, Jae K.

    2018-05-01

    Wastewater consists of valuable resources that could be recovered or reused. Still it is under threat because of ineffective wastewater management and systems. In Thailand, less than 25% of wastewater generated may be treated while then rest is inadequately treated and sent back directly into waterbodies or the environment. Furthermore, the technologies that have been applied may be inefficient and unsustainable. Efficiency, sustainability, and simplicity are important concepts when designing an appropriate wastewater treatment system in developing countries. The objectives of this study were to review and evaluate wastewater treatment technologies and propose a method to improve or select an appropriate technology. An expert system in Excel® program was developed to determine the best solution. Sensitivity analysis was applied to compare and assess uncertainty factors. Due to the different conditions of each area, the key factor of interest was varied. Furthermore, Robust Decision Making tool was applied to determine the best way to improve existing wastewater treatment facility and to choose the most appropriate wastewater treatment technology.

  18. Pattern variation of fish fingerling abundance in the Na Thap Tidal river of Southern Thailand: 2005-2015

    NASA Astrophysics Data System (ADS)

    Donroman, T.; Chesoh, S.; Lim, A.

    2018-04-01

    This study aimed to investigate the variation patterns of fish fingerling abundance based on month, year and sampling site. Monthly collecting data set of the Na Thap tidal river of southern Thailand, were obtained from June 2005 to October 2015. The square root transformation was employed for maintaining the fingerling data normality. Factor analysis was applied for clustering number of fingerling species and multiple linear regression was used to examine the association between fingerling density and year, month and site. Results from factor analysis classified fingerling into 3 factors based on saline preference; saline water, freshwater and ubiquitous species. The results showed a statistically high significant relation between fingerling density, month, year and site. Abundance of saline water and ubiquitous fingerling density showed similar pattern. Downstream site presented highest fingerling density whereas almost of freshwater fingerling occurred in upstream. This finding confirmed that factor analysis and the general linear regression method can be used as an effective tool for predicting and monitoring wild fingerling density in order to sustain fish stock management.

  19. Information theory applications for biological sequence analysis.

    PubMed

    Vinga, Susana

    2014-05-01

    Information theory (IT) addresses the analysis of communication systems and has been widely applied in molecular biology. In particular, alignment-free sequence analysis and comparison greatly benefited from concepts derived from IT, such as entropy and mutual information. This review covers several aspects of IT applications, ranging from genome global analysis and comparison, including block-entropy estimation and resolution-free metrics based on iterative maps, to local analysis, comprising the classification of motifs, prediction of transcription factor binding sites and sequence characterization based on linguistic complexity and entropic profiles. IT has also been applied to high-level correlations that combine DNA, RNA or protein features with sequence-independent properties, such as gene mapping and phenotype analysis, and has also provided models based on communication systems theory to describe information transmission channels at the cell level and also during evolutionary processes. While not exhaustive, this review attempts to categorize existing methods and to indicate their relation with broader transversal topics such as genomic signatures, data compression and complexity, time series analysis and phylogenetic classification, providing a resource for future developments in this promising area.

  20. System analyses on advanced nuclear fuel cycle and waste management

    NASA Astrophysics Data System (ADS)

    Cheon, Myeongguk

    To evaluate the impacts of accelerator-driven transmutation of waste (ATW) fuel cycle on a geological repository, two mathematical models are developed: a reactor system analysis model and a high-level waste (HLW) conditioning model. With the former, fission products and residual trans-uranium (TRU) contained in HLW generated from a reference ATW plant operations are quantified and the reduction of TRU inventory included in commercial spent-nuclear fuel (CSNF) is evaluated. With the latter, an optimized waste loading and composition in solidification of HLW are determined and the volume reduction of waste packages associated with CSNF is evaluated. WACOM, a reactor system analysis code developed in this study for burnup calculation, is validated by ORIGEN2.1 and MCNP. WACOM is used to perform multicycle analysis for the reference lead-bismuth eutectic (LBE) cooled transmuter. By applying the results of this analysis to the reference ATW deployment scenario considered in the ATW roadmap, the HLW generated from the ATW fuel cycle is quantified and the reduction of TRU inventory contained in CSNF is evaluated. A linear programming (LP) model has been developed for determination of an optimized waste loading and composition in solidification of HLW. The model has been applied to a US-defense HLW. The optimum waste loading evaluated by the LP model was compared with that estimated by the Defense Waste Processing Facility (DWPF) in the US and a good agreement was observed. The LP model was then applied to the volume reduction of waste packages associated with CSNF. Based on the obtained reduction factors, the expansion of Yucca Mountain Repository (YMR) capacity is evaluated. It is found that with the reference ATW system, the TRU contained in CSNF could be reduced by a factor of ˜170 in terms of inventory and by a factor of ˜40 in terms of toxicity under the assumed scenario. The number of waste packages related to CSNF could be reduced by a factor of ˜8 in terms of volume and by factor of ˜10 on the basis of electricity generation when a sufficient cooling time for discharged spent fuel and zero process chemicals in HLW are assumed. The expansion factor of Yucca Mountain Repository capacity is estimated to be a factor of 2.4, much smaller than the reduction factor of CSNF waste packages, due to the existence of DOE-owned spent fuel and HLW. The YMR, however, could support 10 times greater electricity generation as long as the statutory capacity of DOE-owned SNF and HLW remains unchanged. This study also showed that the reduction of the number of waste packages could strongly be subject to the heat generation rate of HLW and the amount of process chemicals contained in HLW. For a greater reduction of the number of waste packages, a sufficient cooling time for discharged fuel and efforts to minimize the amount of process chemicals contained in HLW are crucial.

  1. Adhesive blood microsampling systems for steroid measurement via LC-MS/MS in the rat.

    PubMed

    Heussner, Kirsten; Rauh, Manfred; Cordasic, Nada; Menendez-Castro, Carlos; Huebner, Hanna; Ruebner, Matthias; Schmidt, Marius; Hartner, Andrea; Rascher, Wolfgang; Fahlbusch, Fabian B

    2017-04-01

    Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) allows for the direct analysis of multiple hormones in a single probe with minimal sample volume. Rodent-based animal studies strongly rely on microsampling, such as the dry blood spot (DBS) method. However, DBS suffers the drawback of hematocrit-dependence (non-volumetric). Hence, novel volumetric microsampling techniques were introduced recently, allowing sampling of fixed accurate volumes. We compared these methods for steroid analysis in the rat to improve inter-system comparability. We analyzed steroid levels in blood using the absorptive microsampling devices Whatman® 903 Protein Saver Cards, Noviplex™ Plasma Prep Cards and the Mitra™ Microsampling device and compared the obtained results to the respective EDTA plasma levels. Quantitative steroid analysis was performed via LC-MS/MS. For the determination of the plasma volume factor for each steroid, their levels in pooled blood samples from each human adults and rats (18weeks) were compared and the transferability of these factors was evaluated in a new set of juvenile (21days) and adult (18weeks) rats. Hematocrit was determined concomitantly. Using these approaches, we were unable to apply one single volume factor for each steroid. Instead, plasma volume factors had to be adjusted for the recovery rate of each steroid and device individually. The tested microsampling systems did not allow the use of one single volume factor for adult and juvenile rats based on an unexpectedly strong hematocrit-dependency and other steroid specific (pre-analytic) factors. Our study provides correction factors for LC-MS/MS steroid analysis of volumetric and non-volumetric microsampling systems in comparison to plasma. It argues for thorough analysis of chromatographic effects before the use of novel volumetric systems for steroid analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. The multiple decrement life table: a unifying framework for cause-of-death analysis in ecology.

    PubMed

    Carey, James R

    1989-01-01

    The multiple decrement life table is used widely in the human actuarial literature and provides statistical expressions for mortality in three different forms: i) the life table from all causes-of-death combined; ii) the life table disaggregated into selected cause-of-death categories; and iii) the life table with particular causes and combinations of causes eliminated. The purpose of this paper is to introduce the multiple decrement life table to the ecological literature by applying the methods to published death-by-cause information on Rhagoletis pomonella. Interrelations between the current approach and conventional tools used in basic and applied ecology are discussed including the conventional life table, Key Factor Analysis and Abbott's Correction used in toxicological bioassay.

  3. Aggregation factor analysis for protein formulation by a systematic approach using FTIR, SEC and design of experiments techniques.

    PubMed

    Feng, Yan Wen; Ooishi, Ayako; Honda, Shinya

    2012-01-05

    A simple systematic approach using Fourier transform infrared (FTIR) spectroscopy, size exclusion chromatography (SEC) and design of experiments (DOE) techniques was applied to the analysis of aggregation factors for protein formulations in stress and accelerated testings. FTIR and SEC were used to evaluate protein conformational and storage stabilities, respectively. DOE was used to determine the suitable formulation and to analyze both the main effect of single factors and the interaction effect of combined factors on aggregation. Our results indicated that (i) analysis at a low protein concentration is not always applicable to high concentration formulations; (ii) an investigation of interaction effects of combined factors as well as main effects of single factors is effective for improving conformational stability of proteins; (iii) with the exception of pH, the results of stress testing with regard to aggregation factors would be available for suitable formulation instead of performing time-consuming accelerated testing; (iv) a suitable pH condition should not be determined in stress testing but in accelerated testing, because of inconsistent effects of pH on conformational and storage stabilities. In summary, we propose a three-step strategy, using FTIR, SEC and DOE techniques, to effectively analyze the aggregation factors and perform a rapid screening for suitable conditions of protein formulation. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. The Validity and Reliability of the Turkish Version of the Neonatal Skin Risk Assessment Scale.

    PubMed

    Sari, Çiğdem; Altay, Naime

    2017-03-01

    The study created a Turkish translation of the Neonatal Skin Risk Assessment Scale (NSRAS) that was developed by Huffines and Longsdon in 1997. Study authors used a cross-sectional survey design in order to determine the validity and reliability of the Turkish translation. The study was conducted at the neonatal intensive care unit of a university hospital in Ankara between March 15 and June 30, 2014. The research sample included 130 neonatal assessments from 17 patients. Data were collected by questionnaire regarding the characteristics of the participating neonates, 7 nurse observers, and the NSRAS and its subarticles. After translation and back-translation were performed to assess language validity of the scale, necessary corrections were made in line with expert suggestions, and content validity was ensured. Internal consistency of the scale was assessed by its homogeneity, Cronbach's α, and subarticle-general scale grade correlation. Cronbach's α for the scale overall was .88, and Cronbach's α values for the subarticles were between .83 and .90. Results showed a positive relationship among all the subarticles and the overall NSRAS scale grade (P < .01) with correlation values between 0.333 and 0.721. Explanatory and predicative factor analysis was applied for structural validity. Kaiser-Meyer-Olkin analysis was applied for sample sufficiency, and Bartlett test analysis was applied in order to assess the factor analysis of the sample. The Kaiser-Meyer-Olkin coefficient was 0.73, and the χ value found according to the Bartlett test was statistically significant at an advanced level (P < .05). In the 6 subarticles of the scale and in the general scale total grade, a high, positive, and significant relationship among the grades given by the researcher and the nurse observers was found (P < .05). The Turkish NSRAS is reliable and valid.

  5. Mapping brain activity in gradient-echo functional MRI using principal component analysis

    NASA Astrophysics Data System (ADS)

    Khosla, Deepak; Singh, Manbir; Don, Manuel

    1997-05-01

    The detection of sites of brain activation in functional MRI has been a topic of immense research interest and many technique shave been proposed to this end. Recently, principal component analysis (PCA) has been applied to extract the activated regions and their time course of activation. This method is based on the assumption that the activation is orthogonal to other signal variations such as brain motion, physiological oscillations and other uncorrelated noises. A distinct advantage of this method is that it does not require any knowledge of the time course of the true stimulus paradigm. This technique is well suited to EPI image sequences where the sampling rate is high enough to capture the effects of physiological oscillations. In this work, we propose and apply tow methods that are based on PCA to conventional gradient-echo images and investigate their usefulness as tools to extract reliable information on brain activation. The first method is a conventional technique where a single image sequence with alternating on and off stages is subject to a principal component analysis. The second method is a PCA-based approach called the common spatial factor analysis technique (CSF). As the name suggests, this method relies on common spatial factors between the above fMRI image sequence and a background fMRI. We have applied these methods to identify active brain ares during visual stimulation and motor tasks. The results from these methods are compared to those obtained by using the standard cross-correlation technique. We found good agreement in the areas identified as active across all three techniques. The results suggest that PCA and CSF methods have good potential in detecting the true stimulus correlated changes in the presence of other interfering signals.

  6. Machine learning techniques applied to the determination of road suitability for the transportation of dangerous substances.

    PubMed

    Matías, J M; Taboada, J; Ordóñez, C; Nieto, P G

    2007-08-17

    This article describes a methodology to model the degree of remedial action required to make short stretches of a roadway suitable for dangerous goods transport (DGT), particularly pollutant substances, using different variables associated with the characteristics of each segment. Thirty-one factors determining the impact of an accident on a particular stretch of road were identified and subdivided into two major groups: accident probability factors and accident severity factors. Given the number of factors determining the state of a particular road segment, the only viable statistical methods for implementing the model were machine learning techniques, such as multilayer perceptron networks (MLPs), classification trees (CARTs) and support vector machines (SVMs). The results produced by these techniques on a test sample were more favourable than those produced by traditional discriminant analysis, irrespective of whether dimensionality reduction techniques were applied. The best results were obtained using SVMs specifically adapted to ordinal data. This technique takes advantage of the ordinal information contained in the data without penalising the computational load. Furthermore, the technique permits the estimation of the utility function that is latent in expert knowledge.

  7. Impact of maternal education, employment and family size on nutritional status of children.

    PubMed

    Iftikhar, Aisha; Bari, Attia; Bano, Iqbal; Masood, Qaisar

    2017-01-01

    To determine the impact of maternal education, employment, and family size on nutritional status of children. It was case control study conducted at OPD of children Hospital Lahore, from September 2015 to April 2017. Total 340 children (170 cases and 170 controls) with age range of six months to five years along with their mothers were included. Anthropometric measurements were plotted against WHO growth Charts. 170 wasted (<-2 SD) were matched with 170 controls (≥ -2 SD). Maternal education, employment and family size were compared between the cases and control. Confounding variables noted and dichotomized. Univariate analysis was carried out for factors under consideration i.e.; Maternal Education, employment and family size to study the association of each factor. Logistic regression analysis was applied to study the independent association. Maternal education had significant association with growth parameters; OR of 1.32 with confidence interval of (CI= 1.1 to 1.623). Employment status of mothers had OR of 1.132 with insignificant confidence interval of (CI=0.725 to 1.768). Family size had OR of one with insignificant confidence interval (CI=0.8 -1.21). Association remained same after applying bivariate logistic regression analysis. Maternal education has definite and significant effect on nutritional status of children. This is the key factor to be addressed for prevention or improvement of childhood malnutrition. For this it is imperative to launch sustainable programs at national and regional level to uplift women educational status to combat this ever increasing burden of malnutrition.

  8. Logistic regression for risk factor modelling in stuttering research.

    PubMed

    Reed, Phil; Wu, Yaqionq

    2013-06-01

    To outline the uses of logistic regression and other statistical methods for risk factor analysis in the context of research on stuttering. The principles underlying the application of a logistic regression are illustrated, and the types of questions to which such a technique has been applied in the stuttering field are outlined. The assumptions and limitations of the technique are discussed with respect to existing stuttering research, and with respect to formulating appropriate research strategies to accommodate these considerations. Finally, some alternatives to the approach are briefly discussed. The way the statistical procedures are employed are demonstrated with some hypothetical data. Research into several practical issues concerning stuttering could benefit if risk factor modelling were used. Important examples are early diagnosis, prognosis (whether a child will recover or persist) and assessment of treatment outcome. After reading this article you will: (a) Summarize the situations in which logistic regression can be applied to a range of issues about stuttering; (b) Follow the steps in performing a logistic regression analysis; (c) Describe the assumptions of the logistic regression technique and the precautions that need to be checked when it is employed; (d) Be able to summarize its advantages over other techniques like estimation of group differences and simple regression. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Human factors in the Naval Air Systems Command: Computer based training

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

    Seamster, T.L.; Snyder, C.E.; Terranova, M.

    1988-01-01

    Military standards applied to the private sector contracts have a substantial effect on the quality of Computer Based Training (CBT) systems procured for the Naval Air Systems Command. This study evaluated standards regulating the following areas in CBT development and procurement: interactive training systems, cognitive task analysis, and CBT hardware. The objective was to develop some high-level recommendations for evolving standards that will govern the next generation of CBT systems. One of the key recommendations is that there be an integration of the instructional systems development, the human factors engineering, and the software development standards. Recommendations were also made formore » task analysis and CBT hardware standards. (9 refs., 3 figs.)« less

  10. Linear regression analysis: part 14 of a series on evaluation of scientific publications.

    PubMed

    Schneider, Astrid; Hommel, Gerhard; Blettner, Maria

    2010-11-01

    Regression analysis is an important statistical method for the analysis of medical data. It enables the identification and characterization of relationships among multiple factors. It also enables the identification of prognostically relevant risk factors and the calculation of risk scores for individual prognostication. This article is based on selected textbooks of statistics, a selective review of the literature, and our own experience. After a brief introduction of the uni- and multivariable regression models, illustrative examples are given to explain what the important considerations are before a regression analysis is performed, and how the results should be interpreted. The reader should then be able to judge whether the method has been used correctly and interpret the results appropriately. The performance and interpretation of linear regression analysis are subject to a variety of pitfalls, which are discussed here in detail. The reader is made aware of common errors of interpretation through practical examples. Both the opportunities for applying linear regression analysis and its limitations are presented.

  11. Symetrica Measurements at PNNL

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

    Kouzes, Richard T.; Mace, Emily K.; Redding, Rebecca L.

    2009-01-26

    Symetrica is a small company based in Southampton, England, that has developed an algorithm for processing gamma ray spectra obtained from a variety of scintillation detectors. Their analysis method applied to NaI(Tl), BGO, and LaBr spectra results in deconvoluted spectra with the “resolution” improved by about a factor of three to four. This method has also been applied by Symetrica to plastic scintillator with the result that full energy peaks are produced. If this method is valid and operationally viable, it could lead to a significantly improved plastic scintillator based radiation portal monitor system.

  12. Validation of the organizational culture assessment instrument.

    PubMed

    Heritage, Brody; Pollock, Clare; Roberts, Lynne

    2014-01-01

    Organizational culture is a commonly studied area in industrial/organizational psychology due to its important role in workplace behaviour, cognitions, and outcomes. Jung et al.'s [1] review of the psychometric properties of organizational culture measurement instruments noted many instruments have limited validation data despite frequent use in both theoretical and applied situations. The Organizational Culture Assessment Instrument (OCAI) has had conflicting data regarding its psychometric properties, particularly regarding its factor structure. Our study examined the factor structure and criterion validity of the OCAI using robust analysis methods on data gathered from 328 (females = 226, males = 102) Australian employees. Confirmatory factor analysis supported a four factor structure of the OCAI for both ideal and current organizational culture perspectives. Current organizational culture data demonstrated expected reciprocally-opposed relationships between three of the four OCAI factors and the outcome variable of job satisfaction but ideal culture data did not, thus indicating possible weak criterion validity when the OCAI is used to assess ideal culture. Based on the mixed evidence regarding the measure's properties, further examination of the factor structure and broad validity of the measure is encouraged.

  13. Validation of the Organizational Culture Assessment Instrument

    PubMed Central

    Heritage, Brody; Pollock, Clare; Roberts, Lynne

    2014-01-01

    Organizational culture is a commonly studied area in industrial/organizational psychology due to its important role in workplace behaviour, cognitions, and outcomes. Jung et al.'s [1] review of the psychometric properties of organizational culture measurement instruments noted many instruments have limited validation data despite frequent use in both theoretical and applied situations. The Organizational Culture Assessment Instrument (OCAI) has had conflicting data regarding its psychometric properties, particularly regarding its factor structure. Our study examined the factor structure and criterion validity of the OCAI using robust analysis methods on data gathered from 328 (females = 226, males = 102) Australian employees. Confirmatory factor analysis supported a four factor structure of the OCAI for both ideal and current organizational culture perspectives. Current organizational culture data demonstrated expected reciprocally-opposed relationships between three of the four OCAI factors and the outcome variable of job satisfaction but ideal culture data did not, thus indicating possible weak criterion validity when the OCAI is used to assess ideal culture. Based on the mixed evidence regarding the measure's properties, further examination of the factor structure and broad validity of the measure is encouraged. PMID:24667839

  14. Incidence of cardiovascular events and associated risk factors in kidney transplant patients: a competing risks survival analysis.

    PubMed

    Seoane-Pillado, María Teresa; Pita-Fernández, Salvador; Valdés-Cañedo, Francisco; Seijo-Bestilleiro, Rocio; Pértega-Díaz, Sonia; Fernández-Rivera, Constantino; Alonso-Hernández, Ángel; González-Martín, Cristina; Balboa-Barreiro, Vanesa

    2017-03-07

    The high prevalence of cardiovascular risk factors among the renal transplant population accounts for increased mortality. The aim of this study is to determine the incidence of cardiovascular events and factors associated with cardiovascular events in these patients. An observational ambispective follow-up study of renal transplant recipients (n = 2029) in the health district of A Coruña (Spain) during the period 1981-2011 was completed. Competing risk survival analysis methods were applied to estimate the cumulative incidence of developing cardiovascular events over time and to identify which characteristics were associated with the risk of these events. Post-transplant cardiovascular events are defined as the presence of myocardial infarction, invasive coronary artery therapy, cerebral vascular events, new-onset angina, congestive heart failure, rhythm disturbances, peripheral vascular disease and cardiovascular disease and death. The cause of death was identified through the medical history and death certificate using ICD9 (390-459, except: 427.5, 435, 446, 459.0). The mean age of patients at the time of transplantation was 47.0 ± 14.2 years; 62% were male. 16.5% had suffered some cardiovascular disease prior to transplantation and 9.7% had suffered a cardiovascular event. The mean follow-up period for the patients with cardiovascular event was 3.5 ± 4.3 years. Applying competing risk methodology, it was observed that the accumulated incidence of the event was 5.0% one year after transplantation, 8.1% after five years, and 11.9% after ten years. After applying multivariate models, the variables with an independent effect for predicting cardiovascular events are: male sex, age of recipient, previous cardiovascular disorders, pre-transplant smoking and post-transplant diabetes. This study makes it possible to determine in kidney transplant patients, taking into account competitive events, the incidence of post-transplant cardiovascular events and the risk factors of these events. Modifiable risk factors are identified, owing to which, changes in said factors would have a bearing of the incidence of events.

  15. Confirmatory factor analysis applied to the Force Concept Inventory

    NASA Astrophysics Data System (ADS)

    Eaton, Philip; Willoughby, Shannon D.

    2018-06-01

    In 1995, Huffman and Heller used exploratory factor analysis to draw into question the factors of the Force Concept Inventory (FCI). Since then several papers have been published examining the factors of the FCI on larger sets of student responses and understandable factors were extracted as a result. However, none of these proposed factor models have been verified to not be unique to their original sample through the use of independent sets of data. This paper seeks to confirm the factor models proposed by Scott et al. in 2012, and Hestenes et al. in 1992, as well as another expert model proposed within this study through the use of confirmatory factor analysis (CFA) and a sample of 20 822 postinstruction student responses to the FCI. Upon application of CFA using the full sample, all three models were found to fit the data with acceptable global fit statistics. However, when CFA was performed using these models on smaller sample sizes the models proposed by Scott et al. and Eaton and Willoughby were found to be far more stable than the model proposed by Hestenes et al. The goodness of fit of these models to the data suggests that the FCI can be scored on factors that are not unique to a single class. These scores could then be used to comment on how instruction methods effect the performance of students along a single factor and more in-depth analyses of curriculum changes may be possible as a result.

  16. Generalized Structured Component Analysis with Uniqueness Terms for Accommodating Measurement Error

    PubMed Central

    Hwang, Heungsun; Takane, Yoshio; Jung, Kwanghee

    2017-01-01

    Generalized structured component analysis (GSCA) is a component-based approach to structural equation modeling (SEM), where latent variables are approximated by weighted composites of indicators. It has no formal mechanism to incorporate errors in indicators, which in turn renders components prone to the errors as well. We propose to extend GSCA to account for errors in indicators explicitly. This extension, called GSCAM, considers both common and unique parts of indicators, as postulated in common factor analysis, and estimates a weighted composite of indicators with their unique parts removed. Adding such unique parts or uniqueness terms serves to account for measurement errors in indicators in a manner similar to common factor analysis. Simulation studies are conducted to compare parameter recovery of GSCAM and existing methods. These methods are also applied to fit a substantively well-established model to real data. PMID:29270146

  17. Analysis of mortality data from the former USSR: age-period-cohort analysis.

    PubMed

    Willekens, F; Scherbov, S

    1992-01-01

    The objective of this article is to review research on age-period-cohort (APC) analysis of mortality and to trace the effects of contemporary and historical factors on mortality change in the former USSR. Several events in USSR history have exerted a lasting influence on its people. These influences may be captured by an APC model in which the period effects measure the impact of contemporary factors and the cohort effects the past history of individuals which cannot be attributed to age or stage in the life cycle. APC models are extensively applied in the study of mortality. This article presents the statistical theory of the APC models and shows that they belong to the family of generalized linear models. The parameters of the APC model may therefore be estimated by any package of loglinear analysis that allows for hybrid loglinear models.

  18. Evaluation of hierarchical agglomerative cluster analysis methods for discrimination of primary biological aerosol

    NASA Astrophysics Data System (ADS)

    Crawford, I.; Ruske, S.; Topping, D. O.; Gallagher, M. W.

    2015-11-01

    In this paper we present improved methods for discriminating and quantifying primary biological aerosol particles (PBAPs) by applying hierarchical agglomerative cluster analysis to multi-parameter ultraviolet-light-induced fluorescence (UV-LIF) spectrometer data. The methods employed in this study can be applied to data sets in excess of 1 × 106 points on a desktop computer, allowing for each fluorescent particle in a data set to be explicitly clustered. This reduces the potential for misattribution found in subsampling and comparative attribution methods used in previous approaches, improving our capacity to discriminate and quantify PBAP meta-classes. We evaluate the performance of several hierarchical agglomerative cluster analysis linkages and data normalisation methods using laboratory samples of known particle types and an ambient data set. Fluorescent and non-fluorescent polystyrene latex spheres were sampled with a Wideband Integrated Bioaerosol Spectrometer (WIBS-4) where the optical size, asymmetry factor and fluorescent measurements were used as inputs to the analysis package. It was found that the Ward linkage with z-score or range normalisation performed best, correctly attributing 98 and 98.1 % of the data points respectively. The best-performing methods were applied to the BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen-Rocky Mountain Biogenic Aerosol Study) ambient data set, where it was found that the z-score and range normalisation methods yield similar results, with each method producing clusters representative of fungal spores and bacterial aerosol, consistent with previous results. The z-score result was compared to clusters generated with previous approaches (WIBS AnalysiS Program, WASP) where we observe that the subsampling and comparative attribution method employed by WASP results in the overestimation of the fungal spore concentration by a factor of 1.5 and the underestimation of bacterial aerosol concentration by a factor of 5. We suggest that this likely due to errors arising from misattribution due to poor centroid definition and failure to assign particles to a cluster as a result of the subsampling and comparative attribution method employed by WASP. The methods used here allow for the entire fluorescent population of particles to be analysed, yielding an explicit cluster attribution for each particle and improving cluster centroid definition and our capacity to discriminate and quantify PBAP meta-classes compared to previous approaches.

  19. Effects of measurement errors on psychometric measurements in ergonomics studies: Implications for correlations, ANOVA, linear regression, factor analysis, and linear discriminant analysis.

    PubMed

    Liu, Yan; Salvendy, Gavriel

    2009-05-01

    This paper aims to demonstrate the effects of measurement errors on psychometric measurements in ergonomics studies. A variety of sources can cause random measurement errors in ergonomics studies and these errors can distort virtually every statistic computed and lead investigators to erroneous conclusions. The effects of measurement errors on five most widely used statistical analysis tools have been discussed and illustrated: correlation; ANOVA; linear regression; factor analysis; linear discriminant analysis. It has been shown that measurement errors can greatly attenuate correlations between variables, reduce statistical power of ANOVA, distort (overestimate, underestimate or even change the sign of) regression coefficients, underrate the explanation contributions of the most important factors in factor analysis and depreciate the significance of discriminant function and discrimination abilities of individual variables in discrimination analysis. The discussions will be restricted to subjective scales and survey methods and their reliability estimates. Other methods applied in ergonomics research, such as physical and electrophysiological measurements and chemical and biomedical analysis methods, also have issues of measurement errors, but they are beyond the scope of this paper. As there has been increasing interest in the development and testing of theories in ergonomics research, it has become very important for ergonomics researchers to understand the effects of measurement errors on their experiment results, which the authors believe is very critical to research progress in theory development and cumulative knowledge in the ergonomics field.

  20. [Effectiveness of a clinimetric scale for diagnosing vulvovaginal candidosis].

    PubMed

    Reyna Figueroa, Jesús; Morales Rangel, Verónica; Ortiz Ibarra, Federico Javier; Casanova Román, Gerardo; Beltrán Zúñiga, Magdalena

    2004-05-01

    Vulvovaginal candidosis is one of the most frequent infections of the female genital system. It is believed that 75% of women in reproductive life have suffered from vulvovaginal candidosis at least once in their life. To evaluate the effectiveness of a clinimetric scale based on clinical characteristics and factors of risk to diagnose vulvovaginal candidosis and to establish the cut points. A questionnaire was elaborated by means of consensus, there were questions about symptoms and risk factors for the diagnosis. It was applied to women in reproductive age, besides the cervicovaginal culture. The resulting questionnaire was evaluated by means of the analysis of sensitivity according to the criteria of Feinstein. The determination of points of cut was made by means of curves ROC as well as sensitivity, specificity, positive and negative predictive value. The univariable analysis was made by means of the test of chi2 and the exact test of Fisher. We used likelihood ratio for association of variables and the multi-variate logistic regression analysis was made to fit variable potentials. One-hundred forty-two women answered the questionnaire, 39 (27%) had positive isolation to Candida. Vulvar edema (3.49 OR IC 95% 1.16-10.43 p = 0.02) and ardor (OR 2.40 IC 95% 0.88-6.51 p = 0.08) were significant. None of the risk factors were statistically significant. It was reported with sensitivity of 76%, specificity of 38%, VPP 32% and VPN 81% for the = 60 record. The clinimetric scale is brief, valid and easy to apply. It can be used independently of the educative or cultural factors that limit the accomplishment of other forms of diagnosis, such as the vaginal flow exam and the cervicovaginal culture.

  1. INNOVATIVE INSTRUMENTATION AND ANALYSIS OF THE TEMPERATURE MEASUREMENT FOR HIGH TEMPERATURE GASIFICATION

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

    Seong W. Lee

    2004-10-01

    The systematic tests of the gasifier simulator on the clean thermocouple were completed in this reporting period. Within the systematic tests on the clean thermocouple, five (5) factors were considered as the experimental parameters including air flow rate, water flow rate, fine dust particle amount, ammonia addition and high/low frequency device (electric motor). The fractional factorial design method was used in the experiment design with sixteen (16) data sets of readings. Analysis of Variances (ANOVA) was applied to the results from systematic tests. The ANOVA results show that the un-balanced motor vibration frequency did not have the significant impact onmore » the temperature changes in the gasifier simulator. For the fine dust particles testing, the amount of fine dust particles has significant impact to the temperature measurements in the gasifier simulator. The effects of the air and water on the temperature measurements show the same results as reported in the previous report. The ammonia concentration was included as an experimental parameter for the reducing environment in this reporting period. The ammonia concentration does not seem to be a significant factor on the temperature changes. The linear regression analysis was applied to the temperature reading with five (5) factors. The accuracy of the linear regression is relatively low, which is less than 10% accuracy. Nonlinear regression was also conducted to the temperature reading with the same factors. Since the experiments were designed in two (2) levels, the nonlinear regression is not very effective with the dataset (16 readings). An extra central point test was conducted. With the data of the center point testing, the accuracy of the nonlinear regression is much better than the linear regression.« less

  2. Geographical Environment Factors and Risk Assessment of Tick-Borne Encephalitis in Hulunbuir, Northeastern China.

    PubMed

    Li, Yifan; Wang, Juanle; Gao, Mengxu; Fang, Liqun; Liu, Changhua; Lyu, Xin; Bai, Yongqing; Zhao, Qiang; Li, Hairong; Yu, Hongjie; Cao, Wuchun; Feng, Liqiang; Wang, Yanjun; Zhang, Bin

    2017-05-26

    Tick-borne encephalitis (TBE) is one of natural foci diseases transmitted by ticks. Its distribution and transmission are closely related to geographic and environmental factors. Identification of environmental determinates of TBE is of great importance to understanding the general distribution of existing and potential TBE natural foci. Hulunbuir, one of the most severe endemic areas of the disease, is selected as the study area. Statistical analysis, global and local spatial autocorrelation analysis, and regression methods were applied to detect the spatiotemporal characteristics, compare the impact degree of associated factors, and model the risk distribution using the heterogeneity. The statistical analysis of gridded geographic and environmental factors and TBE incidence show that the TBE patients mainly occurred during spring and summer and that there is a significant positive spatial autocorrelation between the distribution of TBE cases and environmental characteristics. The impact degree of these factors on TBE risks has the following descending order: temperature, relative humidity, vegetation coverage, precipitation and topography. A high-risk area with a triangle shape was determined in the central part of Hulunbuir; the low-risk area is located in the two belts next to the outside edge of the central triangle. The TBE risk distribution revealed that the impact of the geographic factors changed depending on the heterogeneity.

  3. Interference-Fit Life Factors for Ball Bearings

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.; Zaretsky, Erwin V.; Poplawski, Joseph V.

    2010-01-01

    The effect of hoop stresses on the rolling-element fatigue life of angular-contact and deep-groove ball bearings was determined for common inner-ring interference fits at the ABEC-5 tolerance level. The analysis was applied to over 1150 bearing configurations and load cases. Hoop stresses were superimposed on the Hertzian principal stresses created by the applied bearing load to calculate the inner-race maximum shearing stress. The resulting fatigue life of the bearing was recalculated through a series of equations. The reduction in the fatigue life is presented as life factors that are applied to the unfactored bearing life. The life factors found in this study ranged from 1.00 (no life reduction)--where there was no net interface pressure--to a worst case of 0.38 (a 62-percent life reduction). For a given interference fit, the reduction in life is different for angular-contact and deep-groove ball bearings. Interference fits also affect the maximum Hertz stress-life relation. Experimental data of Czyzewski, showing the effect of interference fit on rolling-element fatigue life, were reanalyzed to determine the shear stress-life exponent. The Czyzewski data shear stress-life exponent c equals 8.77, compared with the assumed value of 9. Results are presented as tables and charts of life factors for angular-contact and deep-groove ball bearings with light, normal, and heavy loads and interference fits ranging from extremely light to extremely heavy.

  4. Masculinity, Femininity and Androgyny: A Methodological and Theoretical Critique.

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Myers, Margaret

    The three primary purposes of this investigation were: (1) to apply confirmatory factor analysis (CFA) to responses from three instruments--Bem Sex Role Inventory (BSRI), Comrey Personality Scales (CPS), and Australian Sex-Role Scale (ASRS)--designed to measure masculinity (M) and femininity (F); (2) to determine the correlation between M and F on…

  5. Multiple Trajectories of Successful Aging of Older and Younger Cohorts

    ERIC Educational Resources Information Center

    Hsu, Hui-Chuan; Jones, Bobby L.

    2012-01-01

    Purpose: The purpose of this study was to apply group-based trajectory analysis to identify multiple successful aging trajectories by multiple indicators and to examine the factors related to successful aging among the elderly population in Taiwan. Design and Methods: Nation-representative longitudinal data collected from 1993 to 2007 and…

  6. Confirmatory Factor Analysis of Ordinal Variables with Misspecified Models

    ERIC Educational Resources Information Center

    Yang-Wallentin, Fan; Joreskog, Karl G.; Luo, Hao

    2010-01-01

    Ordinal variables are common in many empirical investigations in the social and behavioral sciences. Researchers often apply the maximum likelihood method to fit structural equation models to ordinal data. This assumes that the observed measures have normal distributions, which is not the case when the variables are ordinal. A better approach is…

  7. Spatial modeling of potential woody biomass flow

    Treesearch

    Woodam Chung; Nathaniel Anderson

    2012-01-01

    The flow of woody biomass to end users is determined by economic factors, especially the amount available across a landscape and delivery costs of bioenergy facilities. The objective of this study develop methodology to quantify landscape-level stocks and potential biomass flows using the currently available spatial database road network analysis tool. We applied this...

  8. Determinants of Anabolic-Androgenic Steroid Risk Perceptions in Youth Populations: A Multivariate Analysis

    ERIC Educational Resources Information Center

    Denham, Bryan E.

    2009-01-01

    Grounded conceptually in social cognitive theory, this research examines how personal, behavioral, and environmental factors are associated with risk perceptions of anabolic-androgenic steroids. Ordinal logistic regression and logit log-linear models applied to data gathered from high-school seniors (N = 2,160) in the 2005 Monitoring the Future…

  9. Demographic and Clinical Characteristics Associated with Engagement in Behavioral Health Treatment among Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Croen, Lisa A.; Shankute, Naomi; Davignon, Meghan; Massolo, Maria L.; Yoshida, Cathleen

    2017-01-01

    This study investigates demographic and clinical factors associated with initiation, continuation, and adherence to behavioral health treatment (BHT) among children with autism spectrum disorder. Among 293 insured children referred for applied behavior analysis (ABA) based BHT, 23% never initiated treatment. Among those initiating treatment, 31%…

  10. Estimation of Spatial Dynamic Nonparametric Durbin Models with Fixed Effects

    ERIC Educational Resources Information Center

    Qian, Minghui; Hu, Ridong; Chen, Jianwei

    2016-01-01

    Spatial panel data models have been widely studied and applied in both scientific and social science disciplines, especially in the analysis of spatial influence. In this paper, we consider the spatial dynamic nonparametric Durbin model (SDNDM) with fixed effects, which takes the nonlinear factors into account base on the spatial dynamic panel…

  11. Support vector machine applied to predict the zoonotic potential of E. coli O157 cattle isolates

    USDA-ARS?s Scientific Manuscript database

    Methods based on sequence data analysis facilitate the tracking of disease outbreaks, allow relationships between strains to be reconstructed and virulence factors to be identified. However, these methods are used postfactum after an outbreak has happened. Here, we show that support vector machine a...

  12. Learner Autonomy Scale: A Scale Development Study

    ERIC Educational Resources Information Center

    Orakci, Senol; Gelisli, Yücel

    2017-01-01

    The goal of the study is to develop a scale named "Learner Autonomy Scale" (LAS) for determining the learner autonomy of the students toward English lesson. The proposal scale, composed of 29 items, was applied to two study groups in Turkey. The group of Exploratory Factor Analysis that aims to determine the psychometric properties…

  13. Analyzing seasonal patterns of wildfire exposure factors in Sardinia, Italy

    Treesearch

    Michele Salis; Alan A. Ager; Fermin J. Alcasena; Bachisio Arca; Mark A. Finney; Grazia Pellizzaro; Donatella Spano

    2015-01-01

    In this paper, we applied landscape scale wildfire simulation modeling to explore the spatiotemporal patterns of wildfire likelihood and intensity in the island of Sardinia (Italy). We also performed wildfire exposure analysis for selected highly valued resources on the island to identify areas characterized by high risk. We observed substantial variation in burn...

  14. The Isolation of Motivational, Motoric, and Schedule Effects on Operant Performance: A Modeling Approach

    ERIC Educational Resources Information Center

    Brackney, Ryan J.; Cheung, Timothy H. C.; Neisewander, Janet L.; Sanabria, Federico

    2011-01-01

    Dissociating motoric and motivational effects of pharmacological manipulations on operant behavior is a substantial challenge. To address this problem, we applied a response-bout analysis to data from rats trained to lever press for sucrose on variable-interval (VI) schedules of reinforcement. Motoric, motivational, and schedule factors (effort…

  15. Validity Evidence in Accommodations for English Language Learners and Students with Disabilities

    ERIC Educational Resources Information Center

    Camara, Wayne

    2009-01-01

    The five papers in this special issue of the "Journal of Applied Testing Technology" address fundamental issues of validity when tests are modified or accommodations are provided to English Language Learners (ELL) or students with disabilities. Three papers employed differential item functioning (DIF) and factor analysis and found the…

  16. Discourse Factors in the Evaluation of Language Ability.

    ERIC Educational Resources Information Center

    Litteral, Robert

    Features of connected discourse that have been identified by discourse analysis may be applied to the evaluation of oral proficiency in a second language. For example, in the area of semantics, a speaker's control of the cause-result relationship involves, among other things, the ability to produce the different grammatical and lexical…

  17. An Efficient Taguchi Approach for the Performance Optimization of Health, Safety, Environment and Ergonomics in Generation Companies.

    PubMed

    Azadeh, Ali; Sheikhalishahi, Mohammad

    2015-06-01

    A unique framework for performance optimization of generation companies (GENCOs) based on health, safety, environment, and ergonomics (HSEE) indicators is presented. To rank this sector of industry, the combination of data envelopment analysis (DEA), principal component analysis (PCA), and Taguchi are used for all branches of GENCOs. These methods are applied in an integrated manner to measure the performance of GENCO. The preferred model between DEA, PCA, and Taguchi is selected based on sensitivity analysis and maximum correlation between rankings. To achieve the stated objectives, noise is introduced into input data. The results show that Taguchi outperforms other methods. Moreover, a comprehensive experiment is carried out to identify the most influential factor for ranking GENCOs. The approach developed in this study could be used for continuous assessment and improvement of GENCO's performance in supplying energy with respect to HSEE factors. The results of such studies would help managers to have better understanding of weak and strong points in terms of HSEE factors.

  18. Necessary but Insufficient

    PubMed Central

    2017-01-01

    Abstract Cross-national data production in social science research has increased dramatically in recent decades. Assessing the comparability of data is necessary before drawing substantive conclusions that are based on cross-national data. Researchers assessing data comparability typically use either quantitative methods such as multigroup confirmatory factor analysis or qualitative methods such as online probing. Because both methods have complementary strengths and weaknesses, this study applies both multigroup confirmatory factor analysis and online probing in a mixed-methods approach to assess the comparability of constructive patriotism and nationalism, two important concepts in the study of national identity. Previous measurement invariance tests failed to achieve scalar measurement invariance, which prohibits a cross-national comparison of latent means (Davidov 2009). The arrival of the 2013 ISSP Module on National Identity has encouraged a reassessment of both constructs and a push to understand why scalar invariance cannot be achieved. Using the example of constructive patriotism and nationalism, this study demonstrates how the combination of multigroup confirmatory factor analysis and online probing can uncover and explain issues related to cross-national comparability. PMID:28579643

  19. [Eco-efficiency change and its driving factors in Tongling City of Anhui Province].

    PubMed

    Wang, Yi-Chen; Wang, Yuan; Zhu, Xiao-Dong; Wu, Xiao-Qing; Wang, Ke; Ren, Ke-Xiu; Lu, Gen-Fa

    2011-02-01

    This paper first applied material flow analysis (MFA) to construct three levels of regional eco-efficiency indicators, i.e., regional direct eco-efficiency (RDE), regional total eco-efficiency (RTE), and holistic eco-efficiency (HE), and adopted the newly developed data envelopment analysis (DEA) to evaluate the eco-efficiency of Tongling City during the period of 1990-2008. We also applied Malmquist productivity index (MPI) to explore the eco-efficiency change between two following years and its driving factors. The main results were summarized as 1) though the RDE of Tongling City in 1990-2008 kept an increasing trend, its mean eco-efficiency was not high (close to 0.8 in 80% of the years), being lower than that of the RTE and HE, and 2) the RDE change was closely relevant to the improvement in resource management and the technical input in environmental protection in recent years. In order to further improve the RDE of the City, it would be necessary to raise its eco-efficiency via expanding raw material input, reducing domestic extraction, promoting resources productivity, and taking more measures on environmental protection facilities construction.

  20. Using Separable Nonnegative Matrix Factorization Techniques for the Analysis of Time-Resolved Raman Spectra.

    PubMed

    Luce, Robert; Hildebrandt, Peter; Kuhlmann, Uwe; Liesen, Jörg

    2016-09-01

    The key challenge of time-resolved Raman spectroscopy is the identification of the constituent species and the analysis of the kinetics of the underlying reaction network. In this work we present an integral approach that allows for determining both the component spectra and the rate constants simultaneously from a series of vibrational spectra. It is based on an algorithm for nonnegative matrix factorization that is applied to the experimental data set following a few pre-processing steps. As a prerequisite for physically unambiguous solutions, each component spectrum must include one vibrational band that does not significantly interfere with the vibrational bands of other species. The approach is applied to synthetic "experimental" spectra derived from model systems comprising a set of species with component spectra differing with respect to their degree of spectral interferences and signal-to-noise ratios. In each case, the species involved are connected via monomolecular reaction pathways. The potential and limitations of the approach for recovering the respective rate constants and component spectra are discussed. © The Author(s) 2016.

  1. Enhancement of docosahexaenoic acid production by Schizochytrium SW1 using response surface methodology

    NASA Astrophysics Data System (ADS)

    Nazir, Mohd Yusuf Mohd; Al-Shorgani, Najeeb Kaid Nasser; Kalil, Mohd Sahaid; Hamid, Aidil Abdul

    2015-09-01

    In this study, three factors (fructose concentration, agitation speed and monosodium glutamate (MSG) concentration) were optimized to enhance DHA production by Schizochytrium SW1 using response surface methodology (RSM). Central composite design was applied as the experimental design and analysis of variance (ANOVA) was used to analyze the data. The experiments were conducted using 500 mL flask with 100 mL working volume at 30°C for 96 hours. ANOVA analysis revealed that the process was adequately represented significantly by the quadratic model (p<0.0001) and two of the factors namely agitation speed and MSG concentration significantly affect DHA production (p<0.005). Level of influence for each variable and quadratic polynomial equation were obtained for DHA production by multiple regression analyses. The estimated optimum conditions for maximizing DHA production by SW1 were 70 g/L fructose, 250 rpm agitation speed and 12 g/L MSG. Consequently, the quadratic model was validated by applying of the estimated optimum conditions, which confirmed the model validity and 52.86% of DHA was produced.

  2. Reliability considerations for the total strain range version of strainrange partitioning

    NASA Technical Reports Server (NTRS)

    Wirsching, P. H.; Wu, Y. T.

    1984-01-01

    A proposed total strainrange version of strainrange partitioning (SRP) to enhance the manner in which SRP is applied to life prediction is considered with emphasis on how advanced reliability technology can be applied to perform risk analysis and to derive safety check expressions. Uncertainties existing in the design factors associated with life prediction of a component which experiences the combined effects of creep and fatigue can be identified. Examples illustrate how reliability analyses of such a component can be performed when all design factors in the SRP model are random variables reflecting these uncertainties. The Rackwitz-Fiessler and Wu algorithms are used and estimates of the safety index and the probablity of failure are demonstrated for a SRP problem. Methods of analysis of creep-fatigue data with emphasis on procedures for producing synoptic statistics are presented. An attempt to demonstrate the importance of the contribution of the uncertainties associated with small sample sizes (fatique data) to risk estimates is discussed. The procedure for deriving a safety check expression for possible use in a design criteria document is presented.

  3. The use of multicomponent statistical analysis in hydrogeological environmental research.

    PubMed

    Lambrakis, Nicolaos; Antonakos, Andreas; Panagopoulos, George

    2004-04-01

    The present article examines the possibilities of investigating NO(3)(-) spread in aquifers by applying multicomponent statistical methods (factor, cluster and discriminant analysis) on hydrogeological, hydrochemical, and environmental parameters. A 4-R-Mode factor model determined from the analysis showed its useful role in investigating hydrogeological parameters affecting NO(3)(-) concentration, such as its dilution by upcoming groundwater of the recharge areas. The relationship between NO(3)(-) concentration and agricultural activities can be determined sufficiently by the first factor which relies on NO(3)(-) and SO(4)(2-) of the same origin-that of agricultural fertilizers. The other three factors of R-Mode analysis are not connected directly to the NO(3)(-) problem. They do however, by extracting the role of the unsaturated zone, show an interesting relationship between organic matter content, thickness and saturated hydraulic conductivity. The application of Hirerarchical Cluster Analysis, based on all possible combinations of classification method, showed two main groups of samples. The first group comprises samples from the edges and the second from the central part of the study area. By the application of Discriminant Analysis it was shown that NO(3)(-) and SO(4)(2-) ions are the most significant variables in the discriminant function. Therefore, the first group is considered to comprise all samples from areas not influenced by fertilizers lying on the edges of contaminating activities such as crop cultivation, while the second comprises all the other samples.

  4. Can Link Analysis Be Applied to Identify Behavioral Patterns in Train Recorder Data?

    PubMed

    Strathie, Ailsa; Walker, Guy H

    2016-03-01

    A proof-of-concept analysis was conducted to establish whether link analysis could be applied to data from on-train recorders to detect patterns of behavior that could act as leading indicators of potential safety issues. On-train data recorders capture data about driving behavior on thousands of routine journeys every day and offer a source of untapped data that could be used to offer insights into human behavior. Data from 17 journeys undertaken by six drivers on the same route over a 16-hr period were analyzed using link analysis, and four key metrics were examined: number of links, network density, diameter, and sociometric status. The results established that link analysis can be usefully applied to data captured from on-vehicle recorders. The four metrics revealed key differences in normal driver behavior. These differences have promising construct validity as leading indicators. Link analysis is one method that could be usefully applied to exploit data routinely gathered by on-vehicle data recorders. It facilitates a proactive approach to safety based on leading indicators, offers a clearer understanding of what constitutes normal driving behavior, and identifies trends at the interface of people and systems, which is currently a key area of strategic risk. These research findings have direct applications in the field of transport data monitoring. They offer a means of automatically detecting patterns in driver behavior that could act as leading indicators of problems during operation and that could be used in the proactive monitoring of driver competence, risk management, and even infrastructure design. © 2015, Human Factors and Ergonomics Society.

  5. Analysis of significant factors for dengue fever incidence prediction.

    PubMed

    Siriyasatien, Padet; Phumee, Atchara; Ongruk, Phatsavee; Jampachaisri, Katechan; Kesorn, Kraisak

    2016-04-16

    Many popular dengue forecasting techniques have been used by several researchers to extrapolate dengue incidence rates, including the K-H model, support vector machines (SVM), and artificial neural networks (ANN). The time series analysis methodology, particularly ARIMA and SARIMA, has been increasingly applied to the field of epidemiological research for dengue fever, dengue hemorrhagic fever, and other infectious diseases. The main drawback of these methods is that they do not consider other variables that are associated with the dependent variable. Additionally, new factors correlated to the disease are needed to enhance the prediction accuracy of the model when it is applied to areas of similar climates, where weather factors such as temperature, total rainfall, and humidity are not substantially different. Such drawbacks may consequently lower the predictive power for the outbreak. The predictive power of the forecasting model-assessed by Akaike's information criterion (AIC), Bayesian information criterion (BIC), and the mean absolute percentage error (MAPE)-is improved by including the new parameters for dengue outbreak prediction. This study's selected model outperforms all three other competing models with the lowest AIC, the lowest BIC, and a small MAPE value. The exclusive use of climate factors from similar locations decreases a model's prediction power. The multivariate Poisson regression, however, effectively forecasts even when climate variables are slightly different. Female mosquitoes and seasons were strongly correlated with dengue cases. Therefore, the dengue incidence trends provided by this model will assist the optimization of dengue prevention. The present work demonstrates the important roles of female mosquito infection rates from the previous season and climate factors (represented as seasons) in dengue outbreaks. Incorporating these two factors in the model significantly improves the predictive power of dengue hemorrhagic fever forecasting models, as confirmed by AIC, BIC, and MAPE.

  6. The factor structures and correlates of PTSD in post-conflict Timor-Leste: an analysis of the Harvard Trauma Questionnaire.

    PubMed

    Tay, Alvin Kuowei; Mohsin, Mohammed; Rees, Susan; Steel, Zachary; Tam, Natalino; Soares, Zelia; Baker, Jessica; Silove, Derrick

    2017-05-22

    Post-traumatic stress disorder (PTSD) is the most widely assessed form of mental distress in cross-cultural studies conducted amongst populations exposed to mass conflict and displacement. Nevertheless, there have been longstanding concerns about the universality of PTSD as a diagnostic category when applied across cultures. One approach to examining this question is to assess whether the same factor structure can be identified in culturally diverse populations as has been described in populations of western societies. We examine this issue based on an analysis of the Harvard Trauma Questionnaire (HTQ) completed by a large community sample in conflict-affected Timor-Leste. Culturally adapted measures were applied to assess exposure to conflict-related traumatic events (TEs), ongoing adversities, symptoms of PTSD and psychological distress, and functional impairment amongst a large population sample (n = 2964, response rate: 82.4%) in post-conflict Timor-Leste. Confirmatory factor analyses of the ICD-10, ICD-11, DSM-IV, four-factor Emotional Numbing and five-factor Dysphoric-Arousal PTSD structures, found considerable support for all these models. Based on these classifications, concurrent validity was indicated by logistic regression analyses which showed that being a woman, trauma exposure, ongoing adversity, severe distress, and functional impairment were all associated with PTSD. Although symptom prevalence estimates varied widely based on different classifications, our study found a general agreement in PTSD assignments across contemporary diagnostic systems in a large conflict-affected population in Timor-Leste. Further studies are needed, however, to establish the construct and concurrent validity of PTSD in other cultures.

  7. Quantifying the importance of spatial resolution and other factors through global sensitivity analysis of a flood inundation model

    NASA Astrophysics Data System (ADS)

    Thomas Steven Savage, James; Pianosi, Francesca; Bates, Paul; Freer, Jim; Wagener, Thorsten

    2016-11-01

    Where high-resolution topographic data are available, modelers are faced with the decision of whether it is better to spend computational resource on resolving topography at finer resolutions or on running more simulations to account for various uncertain input factors (e.g., model parameters). In this paper we apply global sensitivity analysis to explore how influential the choice of spatial resolution is when compared to uncertainties in the Manning's friction coefficient parameters, the inflow hydrograph, and those stemming from the coarsening of topographic data used to produce Digital Elevation Models (DEMs). We apply the hydraulic model LISFLOOD-FP to produce several temporally and spatially variable model outputs that represent different aspects of flood inundation processes, including flood extent, water depth, and time of inundation. We find that the most influential input factor for flood extent predictions changes during the flood event, starting with the inflow hydrograph during the rising limb before switching to the channel friction parameter during peak flood inundation, and finally to the floodplain friction parameter during the drying phase of the flood event. Spatial resolution and uncertainty introduced by resampling topographic data to coarser resolutions are much more important for water depth predictions, which are also sensitive to different input factors spatially and temporally. Our findings indicate that the sensitivity of LISFLOOD-FP predictions is more complex than previously thought. Consequently, the input factors that modelers should prioritize will differ depending on the model output assessed, and the location and time of when and where this output is most relevant.

  8. Optimization of a novel method for determination of benzene, toluene, ethylbenzene, and xylenes in hair and waste water samples by carbon nanotubes reinforced sol-gel based hollow fiber solid phase microextraction and gas chromatography using factorial experimental design.

    PubMed

    Es'haghi, Zarrin; Ebrahimi, Mahmoud; Hosseini, Mohammad-Saeid

    2011-05-27

    A novel design of solid phase microextraction fiber containing carbon nanotube reinforced sol-gel which was protected by polypropylene hollow fiber (HF-SPME) was developed for pre-concentration and determination of BTEX in environmental waste water and human hair samples. The method validation was included and satisfying results with high pre-concentration factors were obtained. In the present study orthogonal array experimental design (OAD) procedure with OA(16) (4(4)) matrix was applied to study the effect of four factors influencing the HF-SPME method efficiency: stirring speed, volume of adsorption organic solvent, extraction and desorption time of the sample solution, by which the effect of each factor was estimated using individual contributions as response functions in the screening process. Analysis of variance (ANOVA) was employed for estimating the main significant factors and their percentage contributions in extraction. Calibration curves were plotted using ten spiking levels of BTEX in the concentration ranges of 0.02-30,000ng/mL with correlation coefficients (r) 0.989-0.9991 for analytes. Under the optimized extraction conditions, the method showed good linearity (0.3-20,000ng/L), repeatability, low limits of detections (0.49-0.7ng/L) and excellent pre-concentration factors (185-1872). The best conditions which were estimated then applied for the analysis of BTEX compounds in the real samples. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Multivariate statistical analysis to characterize/discriminate between anthropogenic and geogenic trace elements occurrence in the Campania Plain, Southern Italy.

    PubMed

    Busico, Gianluigi; Cuoco, Emilio; Kazakis, Nerantzis; Colombani, Nicolò; Mastrocicco, Micòl; Tedesco, Dario; Voudouris, Konstantinos

    2018-03-01

    Shallow aquifers are the most accessible reservoirs of potable groundwater; nevertheless, they are also prone to various sources of pollution and it is usually difficult to distinguish between human and natural sources at the watershed scale. The area chosen for this study (the Campania Plain) is characterized by high spatial heterogeneities both in geochemical features and in hydraulic properties. Groundwater mineralization is driven by many processes such as, geothermal activity, weathering of volcanic products and intense human activities. In such a landscape, multivariate statistical analysis has been used to differentiate among the main hydrochemical processes occurring in the area, using three different approaches of factor analysis: (i) major elements, (ii) trace elements, (iii) both major and trace elements. The elaboration of the factor analysis approaches has revealed seven distinct hydrogeochemical processes: i) Salinization (Cl - , Na + ); ii) Carbonate rocks dissolution; iii) Anthropogenic inputs (NO 3 - , SO 4 2- , U, V); iv) Reducing conditions (Fe 2+ , Mn 2+ ); v) Heavy metals contamination (Cr and Ni); vi) Geothermal fluids influence (Li + ); and vii) Volcanic products contribution (As, Rb). Results from this study highlight the need to separately apply factor analysis when a large data set of trace elements is available. In fact, the impact of geothermal fluids in the shallow aquifer was identified from the application of the factor analysis using only trace elements. This study also reveals that the factor analysis of major and trace elements can differentiate between anthropogenic and geogenic sources of pollution in intensively exploited aquifers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. SCOR based key success factors in cooking oil supply chain buyers perspective in Padang City

    NASA Astrophysics Data System (ADS)

    Zahara, Fatimah; Hadiguna, Rika Ampuh

    2017-11-01

    Supply chain of cooking oil is a network of companies from palm oil as raw material to retailers which work to create the value and deliver products into the end consumers. This paper is aimed to study key success factors based on consumer's perspective as the last stage in the supply chain. Consumers who are examined in this study are restaurants management or owners. Restaurant is the biggest consumption of cooking oil. The factors is studied based on Supply Chain Operation Reference (SCOR) version 10.0. Factors used are formulated based on the third-level metrics of SCOR Model. Factors are analyzed using factors analysis. This study found factors which become key success factors in managing supply chain of cooking oil encompass reliability, responsiveness and agility. Key success factors can be applied by governments as policy making and cooking oil companies as formulation of the distribution strategies.

  11. Human Factors Analysis and Layout Guideline Development for the Canadian Surface Combatant (CSC) Project

    DTIC Science & Technology

    2013-04-01

    project was to provide the Royal Canadian Navy ( RCN ) with a set of guidelines on analysis, design, and verification processes for effective room...design, and verification processes that should be used in the development of effective room layouts for Royal Canadian Navy ( RCN ) ships. The primary...designed CSC; however, the guidelines could be applied to the design of any multiple-operator space in any RCN vessel. Results: The development of

  12. Factor analysis of the contextual fine motor questionnaire in children.

    PubMed

    Lin, Chin-Kai; Meng, Ling-Fu; Yu, Ya-Wen; Chen, Che-Kuo; Li, Kuan-Hua

    2014-02-01

    Most studies treat fine motor as one subscale in a developmental test, hence, further factor analysis of fine motor has not been conducted. In fact, fine motor has been treated as a multi-dimensional domain from both clinical and theoretical perspectives, and therefore to know its factors would be valuable. The aim of this study is to analyze the internal consistency and factor validity of the Contextual Fine Motor Questionnaire (CFMQ). Based on the ecological observation and literature, the Contextual Fine Motor Questionnaire (CFMQ) was developed and includes 5 subscales: Pen Control, Tool Use During Handicraft Activities, the Use of Dining Utensils, Connecting and Separating during Dressing and Undressing, and Opening Containers. The main purpose of this study is to establish the factorial validity of the CFMQ through conducting this factor analysis study. Among 1208 questionnaires, 904 were successfully completed. Data from the children's CFMQ submitted by primary care providers was analyzed, including 485 females (53.6%) and 419 males (46.4%) from grades 1 to 5, ranging in age from 82 to 167 months (M=113.9, SD=16.3). Cronbach's alpha was used to measure internal consistency and explorative factor analysis was applied to test the five factor structures within the CFMQ. Results showed that Cronbach's alpha coefficient of the CFMQ for 5 subscales ranged from .77 to .92 and all item-total correlations with corresponding subscales were larger than .4 except one item. The factor loading of almost all items classified to their factor was larger than .5 except 3 items. There were five factors, explaining a total of 62.59% variance for the CFMQ. In conclusion, the remaining 24 items in the 5 subscales of the CFMQ had appropriate internal consistency, test-retest reliability and construct validity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis.

    PubMed

    Camacho, Ana María; Veganzones, Mariano; Claver, Juan; Martín, Francisco; Sevilla, Lorenzo; Sebastián, Miguel Ángel

    2016-09-01

    Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE) simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS₂ grease, silicone oil, and copper paste) to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs). The results show that for small reductions ( r h < 20%), the conventional RCT can be applied because the tribological conditions remain similar. For large reductions ( r h > 20%), it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered.

  14. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis

    PubMed Central

    Camacho, Ana María; Veganzones, Mariano; Claver, Juan; Martín, Francisco; Sevilla, Lorenzo; Sebastián, Miguel Ángel

    2016-01-01

    Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE) simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS2 grease, silicone oil, and copper paste) to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs). The results show that for small reductions (rh < 20%), the conventional RCT can be applied because the tribological conditions remain similar. For large reductions (rh > 20%), it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered. PMID:28773868

  15. Resilient ageing: a concept analysis.

    PubMed

    Hicks, Maxine M; Conner, Norma E

    2014-04-01

    This paper is a report of an analysis of the concept resilient ageing. Unique in comparison with other healthy ageing concepts, resilient ageing can be applied to all older people, regardless of age or affliction. The state of global population expansion in older people over the next 50 years calls for increased health promotion research efforts to ensure the maintenance of health and optimal quality of life for all older people. Literature for this concept analysis was retrieved from several databases, CINAHL, PubMed PsycINFO, for the years 1990-2012. Rodgers's evolutionary method of concept analysis was used because of its applicability to concepts that are still evolving. An integrative research review methodology was applied to peer-reviewed journal articles (n = 46) for an inductive analysis of the concept of resilient ageing. The antecedents, defining attributes, and consequence of resilient ageing were identified. Antecedents to resilient ageing were found to be adversity and protective factors, while the core attributes include coping, hardiness and self-concept. The consequence of the process of resilient ageing was optimal quality of life. Sense of coherence was found to be the surrogate term. The results obtained were further substantiated using Antonovsky's (1979) theory of salutogenesis. A theoretical definition and a model of resilient ageing were developed. In addition, a discussion was provided on the practice, policy and research implications for promoting the development of protective factors and resilient ageing. © 2013 John Wiley & Sons Ltd.

  16. Integration fuzzy analytic network process (ANP) and SWOT business strategy for the development of small and medium enterprises (SME)

    NASA Astrophysics Data System (ADS)

    Khotimah, Bain Khusnul; Irhamni, Firli; Kustiyahningsih, Yenny

    2017-08-01

    Business competition is one risk factor for Small and Medium Enterprises (SME) to set up good management in handling the risk of loss. This proposed research will look for criteria that influence the occurrence of damages based on data from by Cooperative and SME on Batik Madura. Method approach which used Fuzzy Analytic Network Process (FANP) as the weight of interest in decision support systems. Factor analysis of the level losses will influence the performance in the business sector. SWOT analysis combined with FANP method to determine the most appropriate development strategy to be applied industry. From the results of SWOT analysis and FANP, it was found the strategy of the best development to apply business strategy. The raw materials and human resources are available to increase the production capacity of the test results of SWOT analysis SME on Batik Madura. The result measurement of SME are always favourable the position, because the value is well resulted production and the amount is stable revenue which caused SME are in the first quadrant, so the power can exist take advantage of business opportunities. While the trial results of SWOT analysis on SME on Batik Madura in January and March are quadrant of second quadrant because of the number of defective products is quite produced, causing SME are under threat. But although SME suffer threats, SME still have strength on the amount of production and timely delivery.

  17. Development of a stacked ensemble model for forecasting and analyzing daily average PM2.5 concentrations in Beijing, China.

    PubMed

    Zhai, Binxu; Chen, Jianguo

    2018-04-18

    A stacked ensemble model is developed for forecasting and analyzing the daily average concentrations of fine particulate matter (PM 2.5 ) in Beijing, China. Special feature extraction procedures, including those of simplification, polynomial, transformation and combination, are conducted before modeling to identify potentially significant features based on an exploratory data analysis. Stability feature selection and tree-based feature selection methods are applied to select important variables and evaluate the degrees of feature importance. Single models including LASSO, Adaboost, XGBoost and multi-layer perceptron optimized by the genetic algorithm (GA-MLP) are established in the level 0 space and are then integrated by support vector regression (SVR) in the level 1 space via stacked generalization. A feature importance analysis reveals that nitrogen dioxide (NO 2 ) and carbon monoxide (CO) concentrations measured from the city of Zhangjiakou are taken as the most important elements of pollution factors for forecasting PM 2.5 concentrations. Local extreme wind speeds and maximal wind speeds are considered to extend the most effects of meteorological factors to the cross-regional transportation of contaminants. Pollutants found in the cities of Zhangjiakou and Chengde have a stronger impact on air quality in Beijing than other surrounding factors. Our model evaluation shows that the ensemble model generally performs better than a single nonlinear forecasting model when applied to new data with a coefficient of determination (R 2 ) of 0.90 and a root mean squared error (RMSE) of 23.69μg/m 3 . For single pollutant grade recognition, the proposed model performs better when applied to days characterized by good air quality than when applied to days registering high levels of pollution. The overall classification accuracy level is 73.93%, with most misclassifications made among adjacent categories. The results demonstrate the interpretability and generalizability of the stacked ensemble model. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Decision-making in rectal and colorectal cancer: systematic review and qualitative analysis of surgeons' preferences.

    PubMed

    Broc, Guillaume; Gana, Kamel; Denost, Quentin; Quintard, Bruno

    2017-04-01

    Surgeons are experiencing difficulties implementing recommendations not only owing to incomplete, confusing or conflicting information but also to the increasing involvement of patients in decisions relating to their health. This study sought to establish which common factors including heuristic factors guide surgeons' decision-making in colon and rectal cancers. We conducted a systematic literature review of surgeons' decision-making factors related to colon and rectal cancer treatment. Eleven of 349 identified publications were eligible for data analyses. Using the IRaMuTeQ (Interface of R for the Multidimensional Analyses of Texts and Questionnaire), we carried out a qualitative analysis of the significant factors collected in the studies reviewed. Several validation procedures were applied to control the robustness of the findings. Five categories of factors (i.e. patient, surgeon, treatment, tumor and organizational cues) were found to influence surgeons' decision-making. Specifically, all decision criteria including biomedical (e.g. tumor information) and heuristic (e.g. surgeons' dispositional factors) criteria converged towards the factor 'age of patient' in the similarity analysis. In the light of the results, we propose an explanatory model showing the impact of heuristic criteria on medical issues (i.e. diagnosis, prognosis, treatment features, etc.) and thus on decision-making. Finally, the psychosocial complexity involved in decision-making is discussed and a medico-psycho-social grid for use in multidisciplinary meetings is proposed.

  19. A comparison between ten advanced and soft computing models for groundwater qanat potential assessment in Iran using R and GIS

    NASA Astrophysics Data System (ADS)

    Naghibi, Seyed Amir; Pourghasemi, Hamid Reza; Abbaspour, Karim

    2018-02-01

    Considering the unstable condition of water resources in Iran and many other countries in arid and semi-arid regions, groundwater studies are very important. Therefore, the aim of this study is to model groundwater potential by qanat locations as indicators and ten advanced and soft computing models applied to the Beheshtabad Watershed, Iran. Qanat is a man-made underground construction which gathers groundwater from higher altitudes and transmits it to low land areas where it can be used for different purposes. For this purpose, at first, the location of the qanats was detected using extensive field surveys. These qanats were classified into two datasets including training (70%) and validation (30%). Then, 14 influence factors depicting the region's physical, morphological, lithological, and hydrological features were identified to model groundwater potential. Linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), flexible discriminant analysis (FDA), penalized discriminant analysis (PDA), boosted regression tree (BRT), random forest (RF), artificial neural network (ANN), K-nearest neighbor (KNN), multivariate adaptive regression splines (MARS), and support vector machine (SVM) models were applied in R scripts to produce groundwater potential maps. For evaluation of the performance accuracies of the developed models, ROC curve and kappa index were implemented. According to the results, RF had the best performance, followed by SVM and BRT models. Our results showed that qanat locations could be used as a good indicator for groundwater potential. Furthermore, altitude, slope, plan curvature, and profile curvature were found to be the most important influence factors. On the other hand, lithology, land use, and slope aspect were the least significant factors. The methodology in the current study could be used by land use and terrestrial planners and water resource managers to reduce the costs of groundwater resource discovery.

  20. Structural Image Analysis of the Brain in Neuropsychology Using Magnetic Resonance Imaging (MRI) Techniques.

    PubMed

    Bigler, Erin D

    2015-09-01

    Magnetic resonance imaging (MRI) of the brain provides exceptional image quality for visualization and neuroanatomical classification of brain structure. A variety of image analysis techniques provide both qualitative as well as quantitative methods to relate brain structure with neuropsychological outcome and are reviewed herein. Of particular importance are more automated methods that permit analysis of a broad spectrum of anatomical measures including volume, thickness and shape. The challenge for neuropsychology is which metric to use, for which disorder and the timing of when image analysis methods are applied to assess brain structure and pathology. A basic overview is provided as to the anatomical and pathoanatomical relations of different MRI sequences in assessing normal and abnormal findings. Some interpretive guidelines are offered including factors related to similarity and symmetry of typical brain development along with size-normalcy features of brain anatomy related to function. The review concludes with a detailed example of various quantitative techniques applied to analyzing brain structure for neuropsychological outcome studies in traumatic brain injury.

  1. Statistical framework for detection of genetically modified organisms based on Next Generation Sequencing.

    PubMed

    Willems, Sander; Fraiture, Marie-Alice; Deforce, Dieter; De Keersmaecker, Sigrid C J; De Loose, Marc; Ruttink, Tom; Herman, Philippe; Van Nieuwerburgh, Filip; Roosens, Nancy

    2016-02-01

    Because the number and diversity of genetically modified (GM) crops has significantly increased, their analysis based on real-time PCR (qPCR) methods is becoming increasingly complex and laborious. While several pioneers already investigated Next Generation Sequencing (NGS) as an alternative to qPCR, its practical use has not been assessed for routine analysis. In this study a statistical framework was developed to predict the number of NGS reads needed to detect transgene sequences, to prove their integration into the host genome and to identify the specific transgene event in a sample with known composition. This framework was validated by applying it to experimental data from food matrices composed of pure GM rice, processed GM rice (noodles) or a 10% GM/non-GM rice mixture, revealing some influential factors. Finally, feasibility of NGS for routine analysis of GM crops was investigated by applying the framework to samples commonly encountered in routine analysis of GM crops. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. When paradigms collide at the road rail interface: evaluation of a sociotechnical systems theory design toolkit for cognitive work analysis.

    PubMed

    Read, Gemma J M; Salmon, Paul M; Lenné, Michael G

    2016-09-01

    The Cognitive Work Analysis Design Toolkit (CWA-DT) is a recently developed approach that provides guidance and tools to assist in applying the outputs of CWA to design processes to incorporate the values and principles of sociotechnical systems theory. In this paper, the CWA-DT is evaluated based on an application to improve safety at rail level crossings. The evaluation considered the extent to which the CWA-DT met pre-defined methodological criteria and aligned with sociotechnical values and principles. Both process and outcome measures were taken based on the ratings of workshop participants and human factors experts. Overall, workshop participants were positive about the process and indicated that it met the methodological criteria and sociotechnical values. However, expert ratings suggested that the CWA-DT achieved only limited success in producing RLX designs that fully aligned with the sociotechnical approach. Discussion about the appropriateness of the sociotechnical approach in a public safety context is provided. Practitioner Summary: Human factors and ergonomics practitioners need evidence of the effectiveness of methods. A design toolkit for cognitive work analysis, incorporating values and principles from sociotechnical systems theory, was applied to create innovative designs for rail level crossings. Evaluation results based on the application are provided and discussed.

  3. Estimating causal contrasts involving intermediate variables in the presence of selection bias.

    PubMed

    Valeri, Linda; Coull, Brent A

    2016-11-20

    An important goal across the biomedical and social sciences is the quantification of the role of intermediate factors in explaining how an exposure exerts an effect on an outcome. Selection bias has the potential to severely undermine the validity of inferences on direct and indirect causal effects in observational as well as in randomized studies. The phenomenon of selection may arise through several mechanisms, and we here focus on instances of missing data. We study the sign and magnitude of selection bias in the estimates of direct and indirect effects when data on any of the factors involved in the analysis is either missing at random or not missing at random. Under some simplifying assumptions, the bias formulae can lead to nonparametric sensitivity analyses. These sensitivity analyses can be applied to causal effects on the risk difference and risk-ratio scales irrespectively of the estimation approach employed. To incorporate parametric assumptions, we also develop a sensitivity analysis for selection bias in mediation analysis in the spirit of the expectation-maximization algorithm. The approaches are applied to data from a health disparities study investigating the role of stage at diagnosis on racial disparities in colorectal cancer survival. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  4. [Rosenberg self-esteem scale: validation in a representative sample of Chilean adults].

    PubMed

    Rojas-Barahona, Cristian A; Zegers, Beatriz; Förster, Carla E

    2009-06-01

    Self-esteem is positively associated to the well being of people and could be a good mental health indicator. To determine the reliability and validity of the Rosenberg Self-esteem Scale in a Chilean adult sample. The instrument was applied to 473 subjects living in the Metropolitan Region of Santiago, evenly distributed according to gender, age, educational level and income. The Neugarten Life Satisfaction index (LSI-A) was also applied to the sample. Cronbach's alpha for reliability of the scale was 0.754. There was no gender bias and factor analysis grouped items into two factors (5 positive and 5 negative). The instrument had a correlation of 0.455 with the LSI-A. The Rosenberg Self-esteem Scale meets the criteria for validity and reliability of a quality instrument to measure self-esteem in Chile.

  5. Quantification of whispering gallery mode spectrum variability in application to sensing nanobiophotonics

    NASA Astrophysics Data System (ADS)

    Saetchnikov, Anton; Skakun, Victor; Saetchnikov, Vladimir; Tcherniavskaia, Elina; Ostendorf, Andreas

    2017-10-01

    An approach for the automated whispering gallery mode (WGM) signal decomposition and its parameter estimation is discussed. The algorithm is based on the peak picking and can be applied for the preprocessing of the raw signal acquired from the multiplied WGM-based biosensing chips. Quantitative estimations representing physically meaningful parameters of the external disturbing factors on the WGM spectral shape are the output values. Derived parameters can be directly applied to the further deep qualitative and quantitative interpretations of the sensed disturbing factors. The algorithm is tested on both simulated and experimental data taken from the bovine serum albumin biosensing task. The proposed solution is expected to be a useful contribution to the preprocessing phase of the complete data analysis engine and is expected to push the WGM technology toward the real-live sensing nanobiophotonics.

  6. Correction for Metastability in the Quantification of PID in Thin-film Module Testing: Preprint

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

    Hacke, Peter L; Johnston, Steven; Spataru, Sergiu

    A fundamental change in the analysis for the accelerated stress testing of thin-film modules is proposed, whereby power changes due to metastability and other effects that may occur due to the thermal history are removed from the power measurement that we obtain as a function of the applied stress factor. The power of reference modules normalized to an initial state - undergoing the same thermal and light- exposure history but without the applied stress factor such as humidity or voltage bias - is subtracted from that of the stressed modules. For better understanding and appropriate application in standardized tests, themore » method is demonstrated and discussed for potential-induced degradation testing in view of the parallel-occurring but unrelated physical mechanisms that can lead to confounding power changes in the module.« less

  7. Evaluation of liquefaction potential for building code

    NASA Astrophysics Data System (ADS)

    Nunziata, C.; De Nisco, G.; Panza, G. F.

    2008-07-01

    The standard approach for the evaluation of the liquefaction susceptibility is based on the estimation of a safety factor between the cyclic shear resistance to liquefaction and the earthquake induced shear stress. Recently, an updated procedure based on shear-wave velocities (Vs) has been proposed which could be more easily applied. These methods have been applied at La Plaja beach of Catania, that experienced liquefaction because of the 1693 earthquake. The detailed geotechnical and Vs information and the realistic ground motion computed for the 1693 event let us compare the two approaches. The successful application of the Vs procedure, slightly modified to fit historical and safety factor information, even if additional field performances are needed, encourages the development of a guide for liquefaction potential analysis, based on well defined Vs profiles to be included in the italian seismic code.

  8. Progress of soil radionuclide distribution studies for the Nevada Applied Ecology Group: 1981

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

    Essington, E.H.

    Two nuclear sites have been under intensive study by the Nevada Applied Ecology Group (NAEG) during 1980 and 1981, NS201 in area 18 and NS219,221 in area 20. In support of the various studies Los Alamos National Laboratory (Group LS-6) has provided consultation and evaluations relative to radionuclide distributions in soils inundated with radioactive debris from those tests. In addition, a referee effort was also conducted in both analysis of replicate samples and in evaluating various data sets for consistency of results. This report summarizes results of several of the data sets collected to test certain hypotheses relative to radionuclidemore » distributions and factors affecting calculations of hypotheses relative to radionuclide distributions and factors affecting calculations of radionuclide inventories and covers the period February 1980 to May 1981.« less

  9. Predictors of In-Hospital Mortality after Decompressive Hemicraniectomy for Malignant Ischemic Stroke.

    PubMed

    Kamran, Saadat; Salam, Abdul; Akhtar, Naveed; Alboudi, Aymen; Ahmad, Arsalan; Khan, Rabia; Nazir, Rashed; Nadeem, Muhammad; Inshasi, Jihad; ElSotouhy, Ahmed; Al Sulaiti, Ghanim; Shuaib, Ashfaq

    2017-09-01

    The purpose of this retrospective multicenter, pooled-data analysis was to determine the factors associated with in-hospital mortality in decompressive hemicraniectomy (DHC) for malignant middle cerebral artery (MMCA) stroke. The authors reviewed pooled DHC database from 3 countries for patients with MMCA with hospital mortality in spite of DHC to identify factors that predicted in-hospital mortality after DHC. The identified factors were applied to the group of patients who were selected for DHC but either refused surgery and died or stabilized and did not undergo DHC. There were 137 patients who underwent DHC. Multiple logistic regression analysis showed middle cerebral artery (MCA) with additional infarcts (odds ratio [OR], 7.9: 95% confidence interval [CI], 2.4-26; P = .001), preoperative midline shift of septum pellucidum of 1 cm or more (OR, 3.83: 95% CI, 1.13-12.96; P = .031), and patients who remained unconscious on day 7 postoperatively (8.82: 95% CI; OR, 1.08-71.9; P = .042) were significant independent predictors for in-hospital mortality. The identified factors were applied to the group of MMCA patients not operated (n = 19 refused, n = 47 stabilized) single (P < .001), and two predictive factors (P < .001) were significantly more common in patients who died. Whereas two predicative factors were identified in only 9%-18.2% of survivors, the presence of all three predictive factors was seen only in patients who expired (P < .001). The Hosmer-Lemeshow goodness-of-fit statistics (chi-square = 4.65; P value = .589) indicate that the model adequately describes the data. Direct physical factors, such as MCA with additional territory infarct, extent of midline shift, and postoperative consciousness level, bore a significant relationship to in-hospital mortality in MMCA patients undergoing DHC. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  10. Nutritional status in the era of target therapy: poor nutrition is a prognostic factor in non-small cell lung cancer with activating epidermal growth factor receptor mutations.

    PubMed

    Park, Sehhoon; Park, Seongyeol; Lee, Se-Hoon; Suh, Beomseok; Keam, Bhumsuk; Kim, Tae Min; Kim, Dong-Wan; Kim, Young Whan; Heo, Dae Seog

    2016-11-01

    Pretreatment nutritional status is an important prognostic factor in patients treated with conventional cytotoxic chemotherapy. In the era of target therapies, its value is overlooked and has not been investigated. The aim of our study is to evaluate the value of nutritional status in targeted therapy. A total of 2012 patients with non-small cell lung cancer (NSCLC) were reviewed and 630 patients with activating epidermal growth factor receptor (EGFR) mutation treated with EGFR tyrosine kinase inhibitor (TKI) were enrolled for the final analysis. Anemia, body mass index (BMI), and prognostic nutritional index (PNI) were considered as nutritional factors. Hazard ratio (HR), progression-free survival (PFS) and overall survival (OS) for each group were calculated by Cox proportional analysis. In addition, scores were applied for each category and the sum of scores was used for survival analysis. In univariable analysis, anemia (HR, 1.29; p = 0.015), BMI lower than 18.5 (HR, 1.98; p = 0.002), and PNI lower than 45 (HR, 1.57; p < 0.001) were poor prognostic factors for PFS. Among them, BMI and PNI were independent in multi-variable analysis. All of these were also significant prognostic values for OS. The higher the sum of scores, the poorer PFS and OS were observed. Pretreatment nutritional status is a prognostic marker in NSCLC patients treated with EGFR TKI. Hence, baseline nutritional status should be more carefully evaluated and adequate nutrition should be supplied to these patients.

  11. Back to the Consideration of Future Consequences Scale: time to reconsider?

    PubMed

    Rappange, David R; Brouwer, Werner B F; van Exel, N Job A

    2009-10-01

    The Consideration of Future Consequences (CFC) Scale is a measure of the extent to which individuals consider and are influenced by the distant outcomes of current behavior. In this study, the authors conducted factor analysis to investigate the factor structure of the 12-item CFC Scale. The authors found evidence for a multiple factor solution including one completely present-oriented factor consisting of all 7 present-oriented items, and one or two future-oriented factors consisting of the remaining future-oriented items. Further evidence indicated that the present-oriented factor and the 12-item CFC Scale perform similarly in terms of internal consistency and convergent validity. The structure and content of the future-oriented factor(s) is unclear. From the findings, the authors raise questions regarding the construct validity of the CFC Scale, the interpretation of its results, and the usefulness of the CFC scale in its current form in applied research.

  12. Dimensions of the epilepsy foundation concerns index.

    PubMed

    Loring, David W; Larrabee, Glenn J; Meador, Kimford J; Lee, Gregory P

    2005-05-01

    We performed principal component analysis (PCA) of the Epilepsy Foundation Concerns Index scale in 189 patients undergoing evaluation for epilepsy surgery. We identified a five-factor solution in which there were no varimax-rotated factors consisting of fewer than two questions. Factor 1 reflects affective impact on enjoyment of life, Factor 2 reflects general autonomy concerns, Factor 3 reflects fear of seizure recurrence, Factor 4 reflects concern of being a burden to one's family, and Factor 5 reflects a perceived lack of understanding by others. Multiple regression using the Quality of Life in Epilepsy--89 question version; Minnesota Multiphasic Personality Inventory--2; Wechsler Adult Intelligence Scale--third edition; and verbal and visual memory tests as predictors demonstrated a different pattern of association with the factor and summary scores. We conclude that the Epilepsy Foundation Concerns Index is multidimensional, and using a global score based on all items may mask specific concerns that may be relevant when applied to individual patients.

  13. Replace-approximation method for ambiguous solutions in factor analysis of ultrasonic hepatic perfusion

    NASA Astrophysics Data System (ADS)

    Zhang, Ji; Ding, Mingyue; Yuchi, Ming; Hou, Wenguang; Ye, Huashan; Qiu, Wu

    2010-03-01

    Factor analysis is an efficient technique to the analysis of dynamic structures in medical image sequences and recently has been used in contrast-enhanced ultrasound (CEUS) of hepatic perfusion. Time-intensity curves (TICs) extracted by factor analysis can provide much more diagnostic information for radiologists and improve the diagnostic rate of focal liver lesions (FLLs). However, one of the major drawbacks of factor analysis of dynamic structures (FADS) is nonuniqueness of the result when only the non-negativity criterion is used. In this paper, we propose a new method of replace-approximation based on apex-seeking for ambiguous FADS solutions. Due to a partial overlap of different structures, factor curves are assumed to be approximately replaced by the curves existing in medical image sequences. Therefore, how to find optimal curves is the key point of the technique. No matter how many structures are assumed, our method always starts to seek apexes from one-dimensional space where the original high-dimensional data is mapped. By finding two stable apexes from one dimensional space, the method can ascertain the third one. The process can be continued until all structures are found. This technique were tested on two phantoms of blood perfusion and compared to the two variants of apex-seeking method. The results showed that the technique outperformed two variants in comparison of region of interest measurements from phantom data. It can be applied to the estimation of TICs derived from CEUS images and separation of different physiological regions in hepatic perfusion.

  14. Numerical Modeling of Unsteady Thermofluid Dynamics in Cryogenic Systems

    NASA Technical Reports Server (NTRS)

    Majumdar, Alok

    2003-01-01

    A finite volume based network analysis procedure has been applied to model unsteady flow without and with heat transfer. Liquid has been modeled as compressible fluid where the compressibility factor is computed from the equation of state for a real fluid. The modeling approach recognizes that the pressure oscillation is linked with the variation of the compressibility factor; therefore, the speed of sound does not explicitly appear in the governing equations. The numerical results of chilldown process also suggest that the flow and heat transfer are strongly coupled. This is evident by observing that the mass flow rate during 90-second chilldown process increases by factor of ten.

  15. Three-dimensional stress intensity factor analysis of a surface crack in a high-speed bearing

    NASA Technical Reports Server (NTRS)

    Ballarini, Roberto; Hsu, Yingchun

    1990-01-01

    The boundary element method is applied to calculate the stress intensity factors of a surface crack in the rotating inner raceway of a high-speed roller bearing. The three-dimensional model consists of an axially stressed surface cracked plate subjected to a moving Hertzian contact loading. A multidomain formulation and singular crack-tip elements were employed to calculate the stress intensity factors accurately and efficiently for a wide range of configuration parameters. The results can provide the basis for crack growth calculations and fatigue life predictions of high-performance rolling element bearings that are used in aircraft engines.

  16. Updating QR factorization procedure for solution of linear least squares problem with equality constraints.

    PubMed

    Zeb, Salman; Yousaf, Muhammad

    2017-01-01

    In this article, we present a QR updating procedure as a solution approach for linear least squares problem with equality constraints. We reduce the constrained problem to unconstrained linear least squares and partition it into a small subproblem. The QR factorization of the subproblem is calculated and then we apply updating techniques to its upper triangular factor R to obtain its solution. We carry out the error analysis of the proposed algorithm to show that it is backward stable. We also illustrate the implementation and accuracy of the proposed algorithm by providing some numerical experiments with particular emphasis on dense problems.

  17. Single-Molecule Studies of Actin Assembly and Disassembly Factors

    PubMed Central

    Smith, Benjamin A.; Gelles, Jeff; Goode, Bruce L.

    2014-01-01

    The actin cytoskeleton is very dynamic and highly regulated by multiple associated proteins in vivo. Understanding how this system of proteins functions in the processes of actin network assembly and disassembly requires methods to dissect the mechanisms of activity of individual factors and of multiple factors acting in concert. The advent of single-filament and single-molecule fluorescence imaging methods has provided a powerful new approach to discovering actin-regulatory activities and obtaining direct, quantitative insights into the pathways of molecular interactions that regulate actin network architecture and dynamics. Here we describe techniques for acquisition and analysis of single-molecule data, applied to the novel challenges of studying the filament assembly and disassembly activities of actin-associated proteins in vitro. We discuss the advantages of single-molecule analysis in directly visualizing the order of molecular events, measuring the kinetic rates of filament binding and dissociation, and studying the coordination among multiple factors. The methods described here complement traditional biochemical approaches in elucidating actin-regulatory mechanisms in reconstituted filamentous networks. PMID:24630103

  18. Cognitive function and associated factors among older people in Taiwan: age and sex differences.

    PubMed

    Li, Cheng-Lun; Hsu, Hui-Chuan

    2015-01-01

    The aim of this study was to examine cognitive function and the risk and the protective factors by age and sex among Taiwanese older people. The data were from a nation-representative panel of older people in Taiwan. The participants completing both the 2003 and 2007 waves were included for analysis in this study (n=3228). Descriptive analysis and generalized linear model were applied, and the samples were stratified by age groups and by sex. The factors related to higher cognitive function at the intercept included being younger, male, higher education, and doing unpaid work. At the time slope, the age effect and physical function difficulties would reduce the cognitive function across time, while education and providing informational support would increase the cognitive function across time. There were age- and sex-differences in the factors related to cognitive function, particularly on the working status and social participation. Different health promotion strategies to target these populations should be accordingly developed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Shuttle user analysis (study 2.2). Volume 4: Standardized subsystem modules analysis

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The capability to analyze payloads constructed of standardized modules was provided for the planning of future mission models. An inventory of standardized module designs previously obtained was used as a starting point. Some of the conclusions and recommendations are: (1) the two growth factor synthesis methods provide logical configurations for satellite type selection; (2) the recommended method is the one that determines the growth factor as a function of the baseline subsystem weight, since it provides a larger growth factor for small subsystem weights and results in a greater overkill due to standardization; (3) the method that is not recommended is the one that depends upon a subsystem similarity selection, since care must be used in the subsystem similarity selection; (4) it is recommended that the application of standardized subsystem factors be limited to satellites with baseline dry weights between about 700 and 6,500 lbs; and (5) the standardized satellite design approach applies to satellites maintainable in orbit or retrieved for ground maintenance.

  20. Precarious employment in Chile: psychometric properties of the Chilean version of Employment Precariousness Scale in private sector workers.

    PubMed

    Vives-Vergara, Alejandra; González-López, Francisca; Solar, Orielle; Bernales-Baksai, Pamela; González, María José; Benach, Joan

    2017-04-20

    The purpose of this study is to perform a psychometric analysis (acceptability, reliability and factor structure) of the Chilean version of the new Employment Precariousness Scale (EPRES). The data is drawn from a sample of 4,248 private salaried workers with a formal contract from the first Chilean Employment Conditions, Work, Health and Quality of Life (ENETS) survey, applied to a nationally representative sample of the Chilean workforce in 2010. Item and scale-level statistics were performed to assess scaling properties, acceptability and reliability. The six-dimensional factor structure was examined with confirmatory factor analysis. The scale exhibited high acceptability (roughly 80%) and reliability (Cronbach's alpha 0.83) and the factor structure was confirmed. One subscale (rights) demonstrated poorer metric properties without compromising the overall scale. The Chilean version of the Employment Precariousness Scale (EPRES-Ch) demonstrated good metric properties, pointing to its suitability for use in epidemiologic and public health research.

  1. Quantitative analysis of intrinsic and extrinsic factors in the aggregation mechanism of Alzheimer-associated Aβ-peptide

    NASA Astrophysics Data System (ADS)

    Meisl, Georg; Yang, Xiaoting; Frohm, Birgitta; Knowles, Tuomas P. J.; Linse, Sara

    2016-01-01

    Disease related mutations and environmental factors are key determinants of the aggregation mechanism of the amyloid-β peptide implicated in Alzheimer's disease. Here we present an approach to investigate these factors through acquisition of highly reproducible data and global kinetic analysis to determine the mechanistic influence of intrinsic and extrinsic factors on the Aβ aggregation network. This allows us to translate the shift in macroscopic aggregation behaviour into effects on the individual underlying microscopic steps. We apply this work-flow to the disease-associated Aβ42-A2V variant, and to a variation in pH as examples of an intrinsic and an extrinsic perturbation. In both cases, our data reveal a shift towards a mechanism in which a larger fraction of the reactive flux goes via a pathway that generates potentially toxic oligomeric species in a fibril-catalyzed reaction. This is in agreement with the finding that Aβ42-A2V leads to early-onset Alzheimer’s disease and enhances neurotoxicity.

  2. Analysis of Validity and Reliability of the Health Literacy Index for Female Marriage Immigrants (HLI-FMI).

    PubMed

    Yang, Sook Ja; Chee, Yeon Kyung; An, Jisook; Park, Min Hee; Jung, Sunok

    2016-05-01

    The purpose of this study was to obtain an independent evaluation of the factor structure of the 12-item Health Literacy Index for Female Marriage Immigrants (HLI-FMI), the first measure for assessing health literacy for FMIs in Korea. Participants were 250 Asian women who migrated from China, Vietnam, and the Philippines to marry. The HLI-FMI was originally developed and administered in Korean, and other questionnaires were translated into participants' native languages. The HLI-FMI consisted of 2 factors: (1) Access-Understand Health Literacy (7 items) and (2) Appraise-Apply Health Literacy (5 items); Cronbach's α = .73. Confirmatory factor analysis indicated adequate fit for the 2-factor model. HLI-FMI scores were positively associated with time since immigration and Korean proficiency. Based on classical test theory and item response theory, strong support was provided for item discrimination and item difficulty. Findings suggested that the HLI-FMI is an easily administered, reliable, and valid scale. © 2016 APJPH.

  3. Explicit versus implicit motivations: Clarifying how experiences affect turkey hunter satisfaction using revised importance-performance, importance grid, and penalty-reward-contrast analyses

    USGS Publications Warehouse

    Schroeder, Susan A.; Cornicelli, Louis; Fulton, David C.; Merchant, Steven S.

    2018-01-01

    Although research has advanced methods for clarifying factors that relate to customer satisfaction, they have not been embraced by leisure researchers. Using results from a survey of wild turkey hunters, we applied traditional and revised importance-performance (IPA/RIPA), importance-grid analysis (IGA), and penalty-reward-contrast analysis (PRCA) to examine how activity-specific factors influenced satisfaction. Results suggested differences between the explicit and implicit importance of factors related to turkey hunting. Opportunities to kill turkeys were explicitly rated as less important than seeing, hearing, or calling in turkeys, but opportunities for harvest had relatively higher levels of implicit importance. PRCA identified “calling turkeys in” and “hearing gobbling” as minimum requirements that cause dissatisfaction if not fulfilled, but do not provide satisfaction, whereas “seeing turkeys” and an “opportunity to kill a turkey” related to both satisfaction and dissatisfaction. RIPA, IGA, and PRCA could provide valuable insights about factors that may improve satisfaction for leisure participants.

  4. STRUCTURE OF THE UNIVERSITY PERSONALITY INVENTORY FOR CHINESE COLLEGE STUDENTS.

    PubMed

    Zhang, Jieting; Lanza, Stephanie; Zhang, Minqiang; Su, Binyuan

    2015-06-01

    The University Personality Inventory, a mental health instrument for college students, is frequently used for screening in China. However, its unidimensionality has been questioned. This study examined its dimensions to provide more information about the specific mental problems for students at risk. Four subsamples were randomly created from a sample (N = 6,110; M age = 19.1 yr.) of students at a university in China. Principal component analysis with Promax rotation was applied on the first two subsamples to explore dimension of the inventory. Confirmatory factor analysis was conducted on the third subsample to verify the exploratory dimensions. Finally, the identified factors were compared to the Symptom Checklist-90 (SCL-90) to support validity, and sex differences were examined, based on the fourth subsample. Five factors were identified: Physical Symptoms, Cognitive Symptoms, Emotional Vulnerability, Social Avoidance, and Interpersonal Sensitivity, accounting for 60.3% of the variance. All the five factors were significantly correlated with the SCL-90. Women scored significantly higher than men on Cognitive Symptoms and Interpersonal Sensitivity.

  5. Prediction of friction factor of pure water flowing inside vertical smooth and microfin tubes by using artificial neural networks

    NASA Astrophysics Data System (ADS)

    Çebi, A.; Akdoğan, E.; Celen, A.; Dalkilic, A. S.

    2017-02-01

    An artificial neural network (ANN) model of friction factor in smooth and microfin tubes under heating, cooling and isothermal conditions was developed in this study. Data used in ANN was taken from a vertically positioned heat exchanger experimental setup. Multi-layered feed-forward neural network with backpropagation algorithm, radial basis function networks and hybrid PSO-neural network algorithm were applied to the database. Inputs were the ratio of cross sectional flow area to hydraulic diameter, experimental condition number depending on isothermal, heating, or cooling conditions and mass flow rate while the friction factor was the output of the constructed system. It was observed that such neural network based system could effectively predict the friction factor values of the flows regardless of their tube types. A dependency analysis to determine the strongest parameter that affected the network and database was also performed and tube geometry was found to be the strongest parameter of all as a result of analysis.

  6. Multivariate analysis of selected metals in tannery effluents and related soil.

    PubMed

    Tariq, Saadia R; Shah, Munir H; Shaheen, N; Khalique, A; Manzoor, S; Jaffar, M

    2005-06-30

    Effluent and relevant soil samples from 38 tanning units housed in Kasur, Pakistan, were obtained for metal analysis by flame atomic absorption spectrophotometric method. The levels of 12 metals, Na, Ca, K, Mg, Fe, Mn, Cr, Co, Cd, Ni, Pb and Zn were determined in the two media. The data were evaluated towards metal distribution and metal-to-metal correlations. The study evidenced enhanced levels of Cr (391, 16.7 mg/L) and Na (25,519, 9369 mg/L) in tannery effluents and relevant soil samples, respectively. The effluent versus soil trace metal content relationship confirmed that the effluent Cr was strongly correlated with soil Cr. For metal source identification the techniques of principal component analysis, and cluster analysis were applied. The principal component analysis yielded two factors for effluents: factor 1 (49.6% variance) showed significant loading for Ca, Fe, Mn, Cr, Cd, Ni, Pb and Zn, referring to a tanning related source for these metals, and factor 2 (12.6% variance) with higher loadings of Na, K, Mg and Co, was associated with the processes during the skin/hide treatment. Similarly, two factors with a cumulative variance of 34.8% were obtained for soil samples: factor 1 manifested the contribution from Mg, Mn, Co, Cd, Ni and Pb, which though soil-based is basically effluent-derived, while factor 2 was found associated with Na, K, Ca, Cr and Zn which referred to a tannery-based source. The dendograms obtained from cluster analysis, also support the observed results. The study exhibits a gross pollution of soils with Cr at levels far exceeding the stipulated safe limit laid down for tannery effluents.

  7. Harmonic analysis of the precipitation in Greece

    NASA Astrophysics Data System (ADS)

    Nastos, P. T.; Zerefos, C. S.

    2009-04-01

    Greece is a country with a big variety of climates due to its geographical position, to the many mountain ranges and also to the multifarious and long coastline. The mountainous volumes are of such orientation that influences the distribution of the precipitation, having as a result, Western Greece to present great differentiations from Central and Eastern Greece. The application of harmonic analysis to the annual variability of precipitation is the goal of this study, so that the components, which compose the annual variability, be elicited. For this purpose, the mean monthly precipitation data from 30 meteorological stations of National Meteorological Service were used for the time period 1950-2000. The initial target is to reduce the number of variables and to detect structure in the relationships between variables. The most commonly used technique for this purpose is the application of Factor Analysis to a table having as columns the meteorological stations-variables and rows the monthly mean precipitation, so that 2 main factors were calculated, which explain the 98% of total variability of precipitation in Greece. Factor 1, representing the so-called uniform field and interpreting the most of the total variance, refers in fact to the Mediterranean depressions, affecting mainly the West of Greece and also the East Aegean and the Asia Minor coasts. In the process, the Fourier Analysis was applied to the factor scores extracted from the Factor Analysis, so that 2 harmonic components are resulted, which explain above the 98% of the total variability of each main factor, and are due to different synoptic and thermodynamic processes associated with Greece's precipitation construction. Finally, the calculation of the time of occurrence of the maximum precipitation, for each harmonic component of each one of the two main factors, gives the spatial distribution of appearance of the maximum precipitation in the Hellenic region.

  8. Graph theory applied to noise and vibration control in statistical energy analysis models.

    PubMed

    Guasch, Oriol; Cortés, Lluís

    2009-06-01

    A fundamental aspect of noise and vibration control in statistical energy analysis (SEA) models consists in first identifying and then reducing the energy flow paths between subsystems. In this work, it is proposed to make use of some results from graph theory to address both issues. On the one hand, linear and path algebras applied to adjacency matrices of SEA graphs are used to determine the existence of any order paths between subsystems, counting and labeling them, finding extremal paths, or determining the power flow contributions from groups of paths. On the other hand, a strategy is presented that makes use of graph cut algorithms to reduce the energy flow from a source subsystem to a receiver one, modifying as few internal and coupling loss factors as possible.

  9. Ergonomic study and static analysis for new design of electric scooter

    NASA Astrophysics Data System (ADS)

    Fadzly, M. K.; Munirah, Anis; Shayfull, Z.; Saad, Mohd Sazli

    2017-09-01

    The purposes of this project are to design and diversify the function of a battery powered scooter frame which is more practical for the human factor in ergonomic and optimum design. The new design is based on ideas which are studied from existing scooter frame, United States Patent design and European States International Patent design. The final idea of concept design for scooter frame is based on concept chosen from the best characteristics and it is divided into three main difference ideas and the matrix evaluation method is applied. Analysis that applies to frame design, arm, rim and drive train component is based on Cosmos Express program. As a conclusion, the design that is produce are able to carry the maximum also has more practical features in ergonomic view.

  10. Directional dual-tree rational-dilation complex wavelet transform.

    PubMed

    Serbes, Gorkem; Gulcur, Halil Ozcan; Aydin, Nizamettin

    2014-01-01

    Dyadic discrete wavelet transform (DWT) has been used successfully in processing signals having non-oscillatory transient behaviour. However, due to the low Q-factor property of their wavelet atoms, the dyadic DWT is less effective in processing oscillatory signals such as embolic signals (ESs). ESs are extracted from quadrature Doppler signals, which are the output of Doppler ultrasound systems. In order to process ESs, firstly, a pre-processing operation known as phase filtering for obtaining directional signals from quadrature Doppler signals must be employed. Only then, wavelet based methods can be applied to these directional signals for further analysis. In this study, a directional dual-tree rational-dilation complex wavelet transform, which can be applied directly to quadrature signals and has the ability of extracting directional information during analysis, is introduced.

  11. Analysis of motorcyclist riding behaviour on speed table.

    PubMed

    Yuen, Choon Wah; Karim, Mohamed Rehan; Saifizul, Ahmad

    2014-01-01

    This paper focuses on the study of the change of various types of riding behaviour, such as speed, brake force, and throttle force applied, when they ride across the speed table. An instrumented motorcycle equipped with various types of sensor, on-board camera, and data logger was used in acquiring the traffic data in the research. Riders were instructed to ride across two speed tables and the riding data were then analyzed to study the behaviour change from different riders. The results from statistical analysis showed that the riding characteristics such as speed, brake force, and throttle force applied are influenced by distance from hump, riding experience, and travel mileage of riders. Riders tend to apply higher brake intensity at distance point 50 m before the speed table and release the braking at point -10 m after the hump. In short, speed table has different rates of influence towards riding behaviour on different factors, such as distance from hump and different riders' attributes.

  12. Analysis of tribological behaviour of zirconia reinforced Al-SiC hybrid composites using statistical and artificial neural network technique

    NASA Astrophysics Data System (ADS)

    Arif, Sajjad; Tanwir Alam, Md; Ansari, Akhter H.; Bilal Naim Shaikh, Mohd; Arif Siddiqui, M.

    2018-05-01

    The tribological performance of aluminium hybrid composites reinforced with micro SiC (5 wt%) and nano zirconia (0, 3, 6 and 9 wt%) fabricated through powder metallurgy technique were investigated using statistical and artificial neural network (ANN) approach. The influence of zirconia reinforcement, sliding distance and applied load were analyzed with test based on full factorial design of experiments. Analysis of variance (ANOVA) was used to evaluate the percentage contribution of each process parameters on wear loss. ANOVA approach suggested that wear loss be mainly influenced by sliding distance followed by zirconia reinforcement and applied load. Further, a feed forward back propagation neural network was applied on input/output date for predicting and analyzing the wear behaviour of fabricated composite. A very close correlation between experimental and ANN output were achieved by implementing the model. Finally, ANN model was effectively used to find the influence of various control factors on wear behaviour of hybrid composites.

  13. General business theory applied to the physician's practice.

    PubMed

    Shaw, D V

    2002-01-01

    In the pursuit of clinical excellence in today's competitive medical market place, practice managers--clinical or non-clinical--can loose sight of standard management and business principles that are key to success. Also, at times individuals are hesitant to identify a physician practice as a 'business,' preferring to see it as a social good. Still, it is a business--perhaps dealing with a product that is a social good, but still, a business. And, as such, benefits can be derived from a review of business management theory. This article provides a brief review of such theory and also illustrates how to apply this theory to the physician's practice. Key factors in building a successful business will be discussed and applied to the clinical practice, such as resource maximization, rate of return and product mix synergy. Some tools to assist the reader in analyzing their practice will also be provided, such as the RVU Analysis and the Ratio of Service Analysis.

  14. Fiscal Impact of Smoking Cessation in Thailand: A Government Perspective Cost-Benefit Analysis.

    PubMed

    Connolly, Mark P; Kotsopoulos, Nikolaos; Suthipinijtham, Pichaya; Rungruanghiranya, Suthat

    2018-04-01

    We evaluate the broader public economic consequences of investments in smoking cessation that change lifetime productivity, which can influence future government tax revenue and social transfer costs and health care spending. The analysis applies a government perspective framework for assessing the intergenerational relationships between morbidity and mortality and lifetime tax revenue and social transfers received. Applying smoking prevalence in Thailand, a cohort model was developed for smoker and former smokers to estimate impact on lifetime direct taxes and tobacco taxes paid. Age-specific earnings for males and wage appropriate tax rates were applied to estimate net taxes for smokers and former smokers. Introducing smoking cessation leads to lifetime public economic benefits of THB13 998 to THB43 356 per person depending on the age of introducing smoking cessation. Factoring in the costs of smoking cessation therapy, an average return on investment of 1.35 was obtained indicating fiscal surplus generated for government from the combined effect of increased tax revenues and of averting smoking-attributable health care costs.

  15. Analysis of Motorcyclist Riding Behaviour on Speed Table

    PubMed Central

    Yuen, Choon Wah; Karim, Mohamed Rehan; Saifizul, Ahmad

    2014-01-01

    This paper focuses on the study of the change of various types of riding behaviour, such as speed, brake force, and throttle force applied, when they ride across the speed table. An instrumented motorcycle equipped with various types of sensor, on-board camera, and data logger was used in acquiring the traffic data in the research. Riders were instructed to ride across two speed tables and the riding data were then analyzed to study the behaviour change from different riders. The results from statistical analysis showed that the riding characteristics such as speed, brake force, and throttle force applied are influenced by distance from hump, riding experience, and travel mileage of riders. Riders tend to apply higher brake intensity at distance point 50 m before the speed table and release the braking at point −10 m after the hump. In short, speed table has different rates of influence towards riding behaviour on different factors, such as distance from hump and different riders' attributes. PMID:24991638

  16. Influencing factors on cervical cancer screening from the Kurdish women's perspective: A qualitative study.

    PubMed

    Rasul, V H; Cheraghi, M A; Behboodi Moqadam, Z

    2015-01-01

    Aim: This study was aimed to explore and describe the Kurdish women's perception of cervical cancer screening. Methods: A qualitative design based on a conventional content analysis approach. Purposive sampling was applied to 19 women chosen, who had a Pap smear or refused to have one. The study was performed in the Kurdistan Region, Iraq. Semi-structure din-depth individual interviews were carried out to collect data. Results: Four main themes including conflict, belief, and awareness about cervical cancer screening and socio-cultural factors emerged during data analysis Conclusions: Cervical cancer has a high mortality rate in the developing countries. However, only a few Kurdish women participated in the cervical cancer screening in the Kurdistan Region, Iraq. Understanding the factors associated with the women's perception of cervical cancer could guide future educational planning and clinical interventions improve the cervical cancer screening.

  17. Influencing factors on cervical cancer screening from the Kurdish women’s perspective: A qualitative study

    PubMed Central

    Rasul, VH; Cheraghi, MA; Behboodi Moqadam, Z

    2015-01-01

    Aim:This study was aimed to explore and describe the Kurdish women’s perception of cervical cancer screening. Methods: A qualitative design based on a conventional content analysis approach. Purposive sampling was applied to 19 women chosen, who had a Pap smear or refused to have one. The study was performed in the Kurdistan Region, Iraq. Semi-structure din-depth individual interviews were carried out to collect data. Results: Four main themes including conflict, belief, and awareness about cervical cancer screening and socio-cultural factors emerged during data analysis Conclusions: Cervical cancer has a high mortality rate in the developing countries. However, only a few Kurdish women participated in the cervical cancer screening in the Kurdistan Region, Iraq. Understanding the factors associated with the women’s perception of cervical cancer could guide future educational planning and clinical interventions improve the cervical cancer screening. PMID:28255397

  18. Scale of attitudes toward alcohol - Spanish version: evidences of validity and reliability 1

    PubMed Central

    Ramírez, Erika Gisseth León; de Vargas, Divane

    2017-01-01

    ABSTRACT Objective: validate the Scale of attitudes toward alcohol, alcoholism and individuals with alcohol use disorders in its Spanish version. Method: methodological study, involving 300 Colombian nurses. Adopting the classical theory, confirmatory factor analysis was applied without prior examination, based on the strong historical evidence of the factorial structure of the original scale to determine the construct validity of this Spanish version. To assess the reliability, Cronbach’s Alpha and Mc Donalid’s Omega coefficients were used. Results: the confirmatory factor analysis indicated the good fit of the scale model in a four-factor distribution, with a cut-off point at 3.2, demonstrating 66.7% of sensitivity. Conclusions: the Scale of attitudes toward alcohol, alcoholism and individuals with alcohol use disorders in Spanish presented robust psychometric qualities, affirming that the instrument possesses a solid factorial structure and reliability and is capable of precisely measuring the nurses’ atittudes towards the phenomenon proposed. PMID:28793126

  19. Evaluation of Teaching Performance of English Courses by Applying Data Envelopment Analysis and Two-Phase Segmentation

    ERIC Educational Resources Information Center

    Montoneri, Bernard

    2013-01-01

    Effective teaching performance is a crucial factor contributing to students' learning improvement. Students' ratings of teachers at the end of each semester can indirectly provide valuable information about teachers' performance. This paper selects classes of freshmen students taking a course of English in a university of Taiwan from the academic…

  20. Using Recursive Regression to Explore Nonlinear Relationships and Interactions: A Tutorial Applied to a Multicultural Education Study

    ERIC Educational Resources Information Center

    Strang, Kenneth David

    2009-01-01

    This paper discusses how a seldom-used statistical procedure, recursive regression (RR), can numerically and graphically illustrate data-driven nonlinear relationships and interaction of variables. This routine falls into the family of exploratory techniques, yet a few interesting features make it a valuable compliment to factor analysis and…

  1. Analysis of Unit Costs in a University. The Fribourg Example. Program on Institutional Management in Higher Education.

    ERIC Educational Resources Information Center

    Pasquier, Jacques; Sachse, Matthias

    Costing principles are applied to a university by estimating unit costs and their component factors for the university's different inputs, activities, and outputs. The information system used is designed for Fribourg University but could be applicable to other Swiss universities and could serve Switzerland's universities policy. In general, it…

  2. The Theory of Planned Behaviour Applied to Search Engines as a Learning Tool

    ERIC Educational Resources Information Center

    Liaw, Shu-Sheng

    2004-01-01

    Search engines have been developed for helping learners to seek online information. Based on theory of planned behaviour approach, this research intends to investigate the behaviour of using search engines as a learning tool. After factor analysis, the results suggest that perceived satisfaction of search engine, search engines as an information…

  3. Factors Affecting Cheating-Behavior at Undergraduate-Engineering

    ERIC Educational Resources Information Center

    Starovoytova, Diana; Namango, Saul

    2016-01-01

    This study is a fraction of a larger research on cheating in exams at the School of Engineering (SOE). The study design used a descriptive survey approach and a document analysis. A designed confidential self report questioner was applied as the main instrument for this study, with the sample size of 100 subjects, and a response rate of 95%. The…

  4. How Does One Assess the Accuracy of Academic Success Predictors? ROC Analysis Applied to University Entrance Factors

    ERIC Educational Resources Information Center

    Vivo, Juana-Maria; Franco, Manuel

    2008-01-01

    This article attempts to present a novel application of a method of measuring accuracy for academic success predictors that could be used as a standard. This procedure is known as the receiver operating characteristic (ROC) curve, which comes from statistical decision techniques. The statistical prediction techniques provide predictor models and…

  5. Clusters and Factors Associated with Complementary Basic Education in Tanzania Mainland

    ERIC Educational Resources Information Center

    Edwin, Paul; Amina, Msengwa S.; Godwin, Naimani M.

    2017-01-01

    Complimentary Basic Education in Tanzania (COBET) is a community-based programme initiated in 1999 to provide formal education system opportunity to over aged children or children above school age. The COBET program was analyzed using secondary data collected from 21 regions from 2008 to 2012. Cluster analysis was applied to classify the 21…

  6. Use of Item Parceling in Structural Equation Modeling with Missing Data

    ERIC Educational Resources Information Center

    Orcan, Fatih

    2013-01-01

    Parceling is referred to as a procedure for computing sums or average scores across multiple items. Parcels instead of individual items are then used as indicators of latent factors in the structural equation modeling analysis (Bandalos 2002, 2008; Little et al., 2002; Yang, Nay, & Hoyle, 2010). Item parceling may be applied to alleviate some…

  7. Creating Learning Organizations in Higher Education: Applying a Systems Perspective

    ERIC Educational Resources Information Center

    Bui, Hong; Baruch, Yehuda

    2010-01-01

    Purpose: The purpose of this paper is to offer an application of a system model for Senge's five disciplines in higher education (HE) institutions. Design/methodology/approach: The paper utilizes a conceptual framework for the analysis of antecedents and outcomes of Senge's five disciplines, focusing on specific factors unique to the HE sector.…

  8. In the Child's Best Interest: Terminating the Rights of Fathers with Children in Foster Care

    ERIC Educational Resources Information Center

    Olmstead, Spencer B.; McWey, Lenore M.; Henderson, Tammy

    2011-01-01

    The authors conducted a content analysis of appellate court foster care cases in which fathers appealed the termination of their parental rights. Applying the Responsible Fathering framework to organize the contextual issues that impede men from responsibly fathering, the authors sought to learn what factors affect decisions regarding the…

  9. Stagnation in Mortality Decline among Elders in the Netherlands

    ERIC Educational Resources Information Center

    Janssen, Fanny; Nusselder, Wilma J.; Looman, Caspar W. N.; Mackenbach, Johan P.; Kunst, Anton E.

    2003-01-01

    Purpose: This study assesses whether the stagnation of old-age (80+) mortality decline observed in The Netherlands in the 1980s continued in the 1990s and determines which factors contributed to this stagnation. Emphasis is on the role of smoking. Design and Methods: Poisson regression analysis with linear splines was applied to total and…

  10. Simple Assessment Techniques for Soil and Water. Environmental Factors in Small Scale Development Projects. Workshops.

    ERIC Educational Resources Information Center

    Coordination in Development, New York, NY.

    This booklet was produced in response to the growing need for reliable environmental assessment techniques that can be applied to small-scale development projects. The suggested techniques emphasize low-technology environmental analysis. Although these techniques may lack precision, they can be extremely valuable in helping to assure the success…

  11. An Eco-Behavioral Approach to Research in Special Education. The Juniper Gardens Children's Project. [Volume 1].

    ERIC Educational Resources Information Center

    Greenwood, Charles R., Ed.; And Others

    This monograph contains five papers that discuss an eco-behavioral approach to psychology, special education, and applied behavior analysis. The papers point out the advantages of assessing ecological factors (such as natural stimuli and special education procedures) in a quantitative fashion and in a temporal relationship with student behavior.…

  12. Educational Outcomes and Socioeconomic Status: A Decomposition Analysis for Middle-Income Countries

    ERIC Educational Resources Information Center

    Nieto, Sandra; Ramos, Raúl

    2015-01-01

    This article analyzes the factors that explain the gap in educational outcomes between the top and bottom quartile of students in different countries, according to their socioeconomic status. To do so, it uses PISA microdata for 10 middle-income and 2 high-income countries, and applies the Oaxaca-Blinder decomposition method. Its results show that…

  13. A technique for rapid source apportionment applied to ambient organic aerosol measurements from a thermal desorption aerosol gas chromatograph (TAG)

    DOE PAGES

    Zhang, Yaping; Williams, Brent J.; Goldstein, Allen H.; ...

    2016-11-25

    Here, we present a rapid method for apportioning the sources of atmospheric organic aerosol composition measured by gas chromatography–mass spectrometry methods. Here, we specifically apply this new analysis method to data acquired on a thermal desorption aerosol gas chromatograph (TAG) system. Gas chromatograms are divided by retention time into evenly spaced bins, within which the mass spectra are summed. A previous chromatogram binning method was introduced for the purpose of chromatogram structure deconvolution (e.g., major compound classes) (Zhang et al., 2014). Here we extend the method development for the specific purpose of determining aerosol samples' sources. Chromatogram bins are arrangedmore » into an input data matrix for positive matrix factorization (PMF), where the sample number is the row dimension and the mass-spectra-resolved eluting time intervals (bins) are the column dimension. Then two-dimensional PMF can effectively do three-dimensional factorization on the three-dimensional TAG mass spectra data. The retention time shift of the chromatogram is corrected by applying the median values of the different peaks' shifts. Bin width affects chemical resolution but does not affect PMF retrieval of the sources' time variations for low-factor solutions. A bin width smaller than the maximum retention shift among all samples requires retention time shift correction. A six-factor PMF comparison among aerosol mass spectrometry (AMS), TAG binning, and conventional TAG compound integration methods shows that the TAG binning method performs similarly to the integration method. However, the new binning method incorporates the entirety of the data set and requires significantly less pre-processing of the data than conventional single compound identification and integration. In addition, while a fraction of the most oxygenated aerosol does not elute through an underivatized TAG analysis, the TAG binning method does have the ability to achieve molecular level resolution on other bulk aerosol components commonly observed by the AMS.« less

  14. A technique for rapid source apportionment applied to ambient organic aerosol measurements from a thermal desorption aerosol gas chromatograph (TAG)

    NASA Astrophysics Data System (ADS)

    Zhang, Yaping; Williams, Brent J.; Goldstein, Allen H.; Docherty, Kenneth S.; Jimenez, Jose L.

    2016-11-01

    We present a rapid method for apportioning the sources of atmospheric organic aerosol composition measured by gas chromatography-mass spectrometry methods. Here, we specifically apply this new analysis method to data acquired on a thermal desorption aerosol gas chromatograph (TAG) system. Gas chromatograms are divided by retention time into evenly spaced bins, within which the mass spectra are summed. A previous chromatogram binning method was introduced for the purpose of chromatogram structure deconvolution (e.g., major compound classes) (Zhang et al., 2014). Here we extend the method development for the specific purpose of determining aerosol samples' sources. Chromatogram bins are arranged into an input data matrix for positive matrix factorization (PMF), where the sample number is the row dimension and the mass-spectra-resolved eluting time intervals (bins) are the column dimension. Then two-dimensional PMF can effectively do three-dimensional factorization on the three-dimensional TAG mass spectra data. The retention time shift of the chromatogram is corrected by applying the median values of the different peaks' shifts. Bin width affects chemical resolution but does not affect PMF retrieval of the sources' time variations for low-factor solutions. A bin width smaller than the maximum retention shift among all samples requires retention time shift correction. A six-factor PMF comparison among aerosol mass spectrometry (AMS), TAG binning, and conventional TAG compound integration methods shows that the TAG binning method performs similarly to the integration method. However, the new binning method incorporates the entirety of the data set and requires significantly less pre-processing of the data than conventional single compound identification and integration. In addition, while a fraction of the most oxygenated aerosol does not elute through an underivatized TAG analysis, the TAG binning method does have the ability to achieve molecular level resolution on other bulk aerosol components commonly observed by the AMS.

  15. Improved scatter correction with factor analysis for planar and SPECT imaging

    NASA Astrophysics Data System (ADS)

    Knoll, Peter; Rahmim, Arman; Gültekin, Selma; Šámal, Martin; Ljungberg, Michael; Mirzaei, Siroos; Segars, Paul; Szczupak, Boguslaw

    2017-09-01

    Quantitative nuclear medicine imaging is an increasingly important frontier. In order to achieve quantitative imaging, various interactions of photons with matter have to be modeled and compensated. Although correction for photon attenuation has been addressed by including x-ray CT scans (accurate), correction for Compton scatter remains an open issue. The inclusion of scattered photons within the energy window used for planar or SPECT data acquisition decreases the contrast of the image. While a number of methods for scatter correction have been proposed in the past, in this work, we propose and assess a novel, user-independent framework applying factor analysis (FA). Extensive Monte Carlo simulations for planar and tomographic imaging were performed using the SIMIND software. Furthermore, planar acquisition of two Petri dishes filled with 99mTc solutions and a Jaszczak phantom study (Data Spectrum Corporation, Durham, NC, USA) using a dual head gamma camera were performed. In order to use FA for scatter correction, we subdivided the applied energy window into a number of sub-windows, serving as input data. FA results in two factor images (photo-peak, scatter) and two corresponding factor curves (energy spectra). Planar and tomographic Jaszczak phantom gamma camera measurements were recorded. The tomographic data (simulations and measurements) were processed for each angular position resulting in a photo-peak and a scatter data set. The reconstructed transaxial slices of the Jaszczak phantom were quantified using an ImageJ plugin. The data obtained by FA showed good agreement with the energy spectra, photo-peak, and scatter images obtained in all Monte Carlo simulated data sets. For comparison, the standard dual-energy window (DEW) approach was additionally applied for scatter correction. FA in comparison with the DEW method results in significant improvements in image accuracy for both planar and tomographic data sets. FA can be used as a user-independent approach for scatter correction in nuclear medicine.

  16. Equatorial waves simulated by the NCAR community climate model

    NASA Technical Reports Server (NTRS)

    Cheng, Xinhua; Chen, Tsing-Chang

    1988-01-01

    The equatorial planetary waves simulated by the NCAR CCM1 general circulation model were investigated in terms of space-time spectral analysis (Kao, 1968; Hayashi, 1971, 1973) and energetic analysis (Hayashi, 1980). These analyses are particularly applied to grid-point data on latitude circles. In order to test some physical factors which may affect the generation of tropical transient planetary waves, three different model simulations with the CCM1 (the control, the no-mountain, and the no-cloud experiments) were analyzed.

  17. An analysis of the application of AI to the development of intelligent aids for flight crew tasks

    NASA Technical Reports Server (NTRS)

    Baron, S.; Feehrer, C.

    1985-01-01

    This report presents the results of a study aimed at developing a basis for applying artificial intelligence to the flight deck environment of commercial transport aircraft. In particular, the study was comprised of four tasks: (1) analysis of flight crew tasks, (2) survey of the state-of-the-art of relevant artificial intelligence areas, (3) identification of human factors issues relevant to intelligent cockpit aids, and (4) identification of artificial intelligence areas requiring further research.

  18. Factor investing based on Musharakah principle

    NASA Astrophysics Data System (ADS)

    Simon, Shahril; Omar, Mohd; Lazam, Norazliani Md; Amin, Mohd Nazrul Mohd

    2015-10-01

    Shariah stock investing has become a widely discussed topic in financial industry as part of today's investment strategy. The strategy primarily applies market capitalization allocations. However, some researchers have argued that market capitalization weighting is inherently flawed and have advocated replacing market capitalization allocations with factor allocations. In this paper, we discuss the rationale for factor investing based on Musharakah principle. The essential elements or factors of Musharakah principle such as business sector, management capability, profitability growth and capital efficiency are embedded in the Shariah-compliant stock. We then transform these factors into indexation for better analysis and performance measurement. Investment universe for this research covers Malaysian stocks for the period of January 2009 to December 2013. We found out that these factor indexes have historically earned excess returns over market capitalization weighted indexes and experienced higher Sharpe Ratios.

  19. Low-thrust mission risk analysis, with application to a 1980 rendezvous with the comet Encke

    NASA Technical Reports Server (NTRS)

    Yen, C. L.; Smith, D. B.

    1973-01-01

    A computerized failure process simulation procedure is used to evaluate the risk in a solar electric space mission. The procedure uses currently available thrust-subsystem reliability data and performs approximate simulations of the thrust sybsystem burn operation, the system failure processes, and the retargeting operations. The method is applied to assess the risks in carrying out a 1980 rendezvous mission to the comet Encke. Analysis of the results and evaluation of the effects of various risk factors on the mission show that system component failure rates are the limiting factors in attaining a high mission relability. It is also shown that a well-designed trajectory and system operation mode can be used effectively to partially compensate for unreliable thruster performance.

  20. Applying Factor Analysis Combined with Kriging and Information Entropy Theory for Mapping and Evaluating the Stability of Groundwater Quality Variation in Taiwan

    PubMed Central

    Shyu, Guey-Shin; Cheng, Bai-You; Chiang, Chi-Ting; Yao, Pei-Hsuan; Chang, Tsun-Kuo

    2011-01-01

    In Taiwan many factors, whether geological parent materials, human activities, and climate change, can affect the groundwater quality and its stability. This work combines factor analysis and kriging with information entropy theory to interpret the stability of groundwater quality variation in Taiwan between 2005 and 2007. Groundwater quality demonstrated apparent differences between the northern and southern areas of Taiwan when divided by the Wu River. Approximately 52% of the monitoring wells in southern Taiwan suffered from progressing seawater intrusion, causing unstable groundwater quality. Industrial and livestock wastewaters also polluted 59.6% of the monitoring wells, resulting in elevated EC and TOC concentrations in the groundwater. In northern Taiwan, domestic wastewaters polluted city groundwater, resulting in higher NH3-N concentration and groundwater quality instability was apparent among 10.3% of the monitoring wells. The method proposed in this study for analyzing groundwater quality inspects common stability factors, identifies potential areas influenced by common factors, and assists in elevating and reinforcing information in support of an overall groundwater management strategy. PMID:21695030

  1. Symptom structure and severity: a comparison of responses to the positive and negative syndrome scale (PANSS) between patients with PTSD or schizophrenia.

    PubMed

    Stefanovics, Elina A; Krystal, John H; Rosenheck, Robert A

    2014-05-01

    To describe and compare the structure and relative severity of symptoms in clinical trial patients diagnosed with Post Traumatic Stress Disorder (PTSD) or schizophrenia using the Positive and Negative Syndrome Scale (PANSS), developed originally to evaluate symptoms of schizophrenia. This secondary data analysis used baseline PANSS symptom ratings (n=267) from a six-month multicenter randomized placebo-controlled trial of adjunctive risperidone in patients with chronic military-related PTSD. First, using a split-half design, Exploratory Factor Analysis (EFA) was employed to identify independent factors which were then compared to published factor structures for schizophrenia. Next, Confirmatory Factor Analysis (CFA) was applied to the second half of the sample to compare the results of the EFA and published factor structures. Finally, T-tests were used to compare the severity of factor scores between the PTSD sample and the baseline PANSS ratings from the Clinical Antipsychotic Trial for Intervention Effectiveness (CATIE) schizophrenia sample (n=1460). EFA suggested five factors similar to those identified in a summary of 29 schizophrenia studies by Wallwork (Schizophrenia Research, 137:246-250). CFA showed that the five factor Wallwork model fit the data better than the EFA, although both had relatively high goodness of fit. T-tests showed that the PTSD sample had more severe symptoms on the Depressive factor, and the schizophrenia sample on the Positive, Negative, and Disorganized factors, with no significant difference on the Excited factor. Veterans with PTSD had similar symptom structure to patients with schizophrenia on the PANSS, but were less symptomatic on psychosis-related factors and more symptomatic on depression. Dimensional symptom factors can be virtually the same across diagnoses. Published by Elsevier Inc.

  2. Tree-Structured Infinite Sparse Factor Model

    PubMed Central

    Zhang, XianXing; Dunson, David B.; Carin, Lawrence

    2013-01-01

    A tree-structured multiplicative gamma process (TMGP) is developed, for inferring the depth of a tree-based factor-analysis model. This new model is coupled with the nested Chinese restaurant process, to nonparametrically infer the depth and width (structure) of the tree. In addition to developing the model, theoretical properties of the TMGP are addressed, and a novel MCMC sampler is developed. The structure of the inferred tree is used to learn relationships between high-dimensional data, and the model is also applied to compressive sensing and interpolation of incomplete images. PMID:25279389

  3. An examination of the Rosenberg Self-Esteem Scale using collegiate wheelchair basketball student athletes.

    PubMed

    Vermillion, Mark; Dodder, Richard A

    2007-04-01

    The purpose was to examine the construct validity of the Rosenberg Self-esteem Scale (RSES). The construct validity of the scale was examined by applying it to collegiate wheelchair basketball student athletes at an NCAA sanctioned wheelchair basketball tournament at a mid-sized university in the south central United States (N=68). In accordance with previous research on the scale, Cronbach alpha was .86; confirmatory factor analysis supported a one-factor structure. The scale is useful for measuring global self-esteem in collegiate wheelchair basketball student athletes.

  4. Directivity in NGA earthquake ground motions: Analysis using isochrone theory

    USGS Publications Warehouse

    Spudich, P.; Chiou, B.S.J.

    2008-01-01

    We present correction factors that may be applied to the ground motion prediction relations of Abrahamson and Silva, Boore and Atkinson, Campbell and Bozorgnia, and Chiou and Youngs (all in this volume) to model the azimuthally varying distribution of the GMRotI50 component of ground motion (commonly called 'directivity') around earthquakes. Our correction factors may be used for planar or nonplanar faults having any dip or slip rake (faulting mechanism). Our correction factors predict directivity-induced variations of spectral acceleration that are roughly half of the strike-slip variations predicted by Somerville et al. (1997), and use of our factors reduces record-to-record sigma by about 2-20% at 5 sec or greater period. ?? 2008, Earthquake Engineering Research Institute.

  5. Neutron Spectroscopic Factors from Transfer Reactions

    NASA Astrophysics Data System (ADS)

    Lee, Jenny; Tsang, M. B.

    2007-05-01

    We have extracted the ground state to ground state neutron spectroscopic factors for 80 nuclei ranging in Z from 3 to 24 by analyzing the past measurements of the angular distributions from (d,p) and (p,d) reactions. We demonstrate an approach that provides systematic and consistent values with a minimum of assumptions. A three-body model with global optical potentials and standard geometry of n-potential is applied. For the 60 nuclei where modern shell model calculations are available, such analysis reproduces, to within 20%, the experimental spectroscopic factors for most nuclei. If we constraint the nucleon-target optical potential and the geometries of the bound neutron-wave function with the modern Hartree-Fock calculations, our deduced neutron spectroscopic factors are reduced by 30% on average.

  6. [A prediction model for internet game addiction in adolescents: using a decision tree analysis].

    PubMed

    Kim, Ki Sook; Kim, Kyung Hee

    2010-06-01

    This study was designed to build a theoretical frame to provide practical help to prevent and manage adolescent internet game addiction by developing a prediction model through a comprehensive analysis of related factors. The participants were 1,318 students studying in elementary, middle, and high schools in Seoul and Gyeonggi Province, Korea. Collected data were analyzed using the SPSS program. Decision Tree Analysis using the Clementine program was applied to build an optimum and significant prediction model to predict internet game addiction related to various factors, especially parent related factors. From the data analyses, the prediction model for factors related to internet game addiction presented with 5 pathways. Causative factors included gender, type of school, siblings, economic status, religion, time spent alone, gaming place, payment to Internet café, frequency, duration, parent's ability to use internet, occupation (mother), trust (father), expectations regarding adolescent's study (mother), supervising (both parents), rearing attitude (both parents). The results suggest preventive and managerial nursing programs for specific groups by path. Use of this predictive model can expand the role of school nurses, not only in counseling addicted adolescents but also, in developing and carrying out programs with parents and approaching adolescents individually through databases and computer programming.

  7. Risk Assessment of Groundwater Contamination: A Multilevel Fuzzy Comprehensive Evaluation Approach Based on DRASTIC Model

    PubMed Central

    Zhang, Yan; Zhong, Ming

    2013-01-01

    Groundwater contamination is a serious threat to water supply. Risk assessment of groundwater contamination is an effective way to protect the safety of groundwater resource. Groundwater is a complex and fuzzy system with many uncertainties, which is impacted by different geological and hydrological factors. In order to deal with the uncertainty in the risk assessment of groundwater contamination, we propose an approach with analysis hierarchy process and fuzzy comprehensive evaluation integrated together. Firstly, the risk factors of groundwater contamination are identified by the sources-pathway-receptor-consequence method, and a corresponding index system of risk assessment based on DRASTIC model is established. Due to the complexity in the process of transitions between the possible pollution risks and the uncertainties of factors, the method of analysis hierarchy process is applied to determine the weights of each factor, and the fuzzy sets theory is adopted to calculate the membership degrees of each factor. Finally, a case study is presented to illustrate and test this methodology. It is concluded that the proposed approach integrates the advantages of both analysis hierarchy process and fuzzy comprehensive evaluation, which provides a more flexible and reliable way to deal with the linguistic uncertainty and mechanism uncertainty in groundwater contamination without losing important information. PMID:24453883

  8. Determination of effective loss factors in reduced SEA models

    NASA Astrophysics Data System (ADS)

    Chimeno Manguán, M.; Fernández de las Heras, M. J.; Roibás Millán, E.; Simón Hidalgo, F.

    2017-01-01

    The definition of Statistical Energy Analysis (SEA) models for large complex structures is highly conditioned by the classification of the structure elements into a set of coupled subsystems and the subsequent determination of the loss factors representing both the internal damping and the coupling between subsystems. The accurate definition of the complete system can lead to excessively large models as the size and complexity increases. This fact can also rise practical issues for the experimental determination of the loss factors. This work presents a formulation of reduced SEA models for incomplete systems defined by a set of effective loss factors. This reduced SEA model provides a feasible number of subsystems for the application of the Power Injection Method (PIM). For structures of high complexity, their components accessibility can be restricted, for instance internal equipments or panels. For these cases the use of PIM to carry out an experimental SEA analysis is not possible. New methods are presented for this case in combination with the reduced SEA models. These methods allow defining some of the model loss factors that could not be obtained through PIM. The methods are validated with a numerical analysis case and they are also applied to an actual spacecraft structure with accessibility restrictions: a solar wing in folded configuration.

  9. Analysis of 230 cases of emergent surgery for obstructing colon cancer--lessons learned.

    PubMed

    Aslar, Ahmet Kessaf; Ozdemir, Süleyman; Mahmoudi, Hatim; Kuzu, Mehmet Ayhan

    2011-01-01

    We aimed to identify prognostic factors affecting clinical outcomes in emergent primary resection. A retrospective analysis of prospectively acquired data of 230 consecutive emergent patients between August 1994 and January 2005 were evaluated in this study. Sixty-nine patients applied with right colon obstruction and 161 patients with left. Resection and primary anastomosis was carried out in 128 patients and resection and stoma in 102 patients. The patients were divided into two cohorts: patients who developed poor outcome within 30 days after surgery and those who did not. Major morbidity or mortality were reported in 60 (26.1%) patients. Analysis revealed that the most important prognostic factors for poor outcome were American Anesthesiology Association (ASA) grade ≥3, Acute Physiology and Chronic Health Evaluation II (APACHE II) score ≥11, age >60 years, presence of peritonitis, and surgery during on-call hours. Age >60 years and on-call surgery were determinant factors in right-sided obstructions, whereas ASA grade ≥3, APACHE II score ≥11, and presence of peritonitis were determinant factors in left-sided obstructions. All these factors but the timing of the operation emphasize the pivotal role of the patient's physiological condition on admission. Accurate preoperative evaluation might predict the clinical outcome and help in establishing the most appropriate treatment.

  10. STATISTICAL ANALYSIS OF SNAP 10A THERMOELECTRIC CONVERTER ELEMENT PROCESS DEVELOPMENT VARIABLES

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

    Fitch, S.H.; Morris, J.W.

    1962-12-15

    Statistical analysis, primarily analysis of variance, was applied to evaluate several factors involved in the development of suitable fabrication and processing techniques for the production of lead telluride thermoelectric elements for the SNAP 10A energy conversion system. The analysis methods are described as to their application for determining the effects of various processing steps, estabIishing the value of individual operations, and evaluating the significance of test results. The elimination of unnecessary or detrimental processing steps was accomplished and the number of required tests was substantially reduced by application of these statistical methods to the SNAP 10A production development effort. (auth)

  11. Stepwise Regression Analysis of MDOE Balance Calibration Data Acquired at DNW

    NASA Technical Reports Server (NTRS)

    DeLoach, RIchard; Philipsen, Iwan

    2007-01-01

    This paper reports a comparison of two experiment design methods applied in the calibration of a strain-gage balance. One features a 734-point test matrix in which loads are varied systematically according to a method commonly applied in aerospace research and known in the literature of experiment design as One Factor At a Time (OFAT) testing. Two variations of an alternative experiment design were also executed on the same balance, each with different features of an MDOE experiment design. The Modern Design of Experiments (MDOE) is an integrated process of experiment design, execution, and analysis applied at NASA's Langley Research Center to achieve significant reductions in cycle time, direct operating cost, and experimental uncertainty in aerospace research generally and in balance calibration experiments specifically. Personnel in the Instrumentation and Controls Department of the German Dutch Wind Tunnels (DNW) have applied MDOE methods to evaluate them in the calibration of a balance using an automated calibration machine. The data have been sent to Langley Research Center for analysis and comparison. This paper reports key findings from this analysis. The chief result is that a 100-point calibration exploiting MDOE principles delivered quality comparable to a 700+ point OFAT calibration with significantly reduced cycle time and attendant savings in direct and indirect costs. While the DNW test matrices implemented key MDOE principles and produced excellent results, additional MDOE concepts implemented in balance calibrations at Langley Research Center are also identified and described.

  12. A regional classification scheme for estimating reference water quality in streams using land-use-adjusted spatial regression-tree analysis

    USGS Publications Warehouse

    Robertson, Dale M.; Saad, D.A.; Heisey, D.M.

    2006-01-01

    Various approaches are used to subdivide large areas into regions containing streams that have similar reference or background water quality and that respond similarly to different factors. For many applications, such as establishing reference conditions, it is preferable to use physical characteristics that are not affected by human activities to delineate these regions. However, most approaches, such as ecoregion classifications, rely on land use to delineate regions or have difficulties compensating for the effects of land use. Land use not only directly affects water quality, but it is often correlated with the factors used to define the regions. In this article, we describe modifications to SPARTA (spatial regression-tree analysis), a relatively new approach applied to water-quality and environmental characteristic data to delineate zones with similar factors affecting water quality. In this modified approach, land-use-adjusted (residualized) water quality and environmental characteristics are computed for each site. Regression-tree analysis is applied to the residualized data to determine the most statistically important environmental characteristics describing the distribution of a specific water-quality constituent. Geographic information for small basins throughout the study area is then used to subdivide the area into relatively homogeneous environmental water-quality zones. For each zone, commonly used approaches are subsequently used to define its reference water quality and how its water quality responds to changes in land use. SPARTA is used to delineate zones of similar reference concentrations of total phosphorus and suspended sediment throughout the upper Midwestern part of the United States. ?? 2006 Springer Science+Business Media, Inc.

  13. Three-way analysis of the UPLC-PDA dataset for the multicomponent quantitation of hydrochlorothiazide and olmesartan medoxomil in tablets by parallel factor analysis and three-way partial least squares.

    PubMed

    Dinç, Erdal; Ertekin, Zehra Ceren

    2016-01-01

    An application of parallel factor analysis (PARAFAC) and three-way partial least squares (3W-PLS1) regression models to ultra-performance liquid chromatography-photodiode array detection (UPLC-PDA) data with co-eluted peaks in the same wavelength and time regions was described for the multicomponent quantitation of hydrochlorothiazide (HCT) and olmesartan medoxomil (OLM) in tablets. Three-way dataset of HCT and OLM in their binary mixtures containing telmisartan (IS) as an internal standard was recorded with a UPLC-PDA instrument. Firstly, the PARAFAC algorithm was applied for the decomposition of three-way UPLC-PDA data into the chromatographic, spectral and concentration profiles to quantify the concerned compounds. Secondly, 3W-PLS1 approach was subjected to the decomposition of a tensor consisting of three-way UPLC-PDA data into a set of triads to build 3W-PLS1 regression for the analysis of the same compounds in samples. For the proposed three-way analysis methods in the regression and prediction steps, the applicability and validity of PARAFAC and 3W-PLS1 models were checked by analyzing the synthetic mixture samples, inter-day and intra-day samples, and standard addition samples containing HCT and OLM. Two different three-way analysis methods, PARAFAC and 3W-PLS1, were successfully applied to the quantitative estimation of the solid dosage form containing HCT and OLM. Regression and prediction results provided from three-way analysis were compared with those obtained by traditional UPLC method. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Chemometrics Methods for Specificity, Authenticity and Traceability Analysis of Olive Oils: Principles, Classifications and Applications.

    PubMed

    Messai, Habib; Farman, Muhammad; Sarraj-Laabidi, Abir; Hammami-Semmar, Asma; Semmar, Nabil

    2016-11-17

    Olive oils (OOs) show high chemical variability due to several factors of genetic, environmental and anthropic types. Genetic and environmental factors are responsible for natural compositions and polymorphic diversification resulting in different varietal patterns and phenotypes. Anthropic factors, however, are at the origin of different blends' preparation leading to normative, labelled or adulterated commercial products. Control of complex OO samples requires their (i) characterization by specific markers; (ii) authentication by fingerprint patterns; and (iii) monitoring by traceability analysis. These quality control and management aims require the use of several multivariate statistical tools: specificity highlighting requires ordination methods; authentication checking calls for classification and pattern recognition methods; traceability analysis implies the use of network-based approaches able to separate or extract mixed information and memorized signals from complex matrices. This chapter presents a review of different chemometrics methods applied for the control of OO variability from metabolic and physical-chemical measured characteristics. The different chemometrics methods are illustrated by different study cases on monovarietal and blended OO originated from different countries. Chemometrics tools offer multiple ways for quantitative evaluations and qualitative control of complex chemical variability of OO in relation to several intrinsic and extrinsic factors.

  15. Cost Analysis for Large Civil Transport Rotorcraft

    NASA Technical Reports Server (NTRS)

    Coy, John J.

    2006-01-01

    This paper presents cost analysis of purchase price and DOC+I (direct operating cost plus interest) that supports NASA s study of three advanced rotorcraft concepts that could enter commercial transport service within 10 to 15 years. The components of DOC+I are maintenance, flight crew, fuel, depreciation, insurance, and finance. The cost analysis aims at VTOL (vertical takeoff and landing) and CTOL (conventional takeoff and landing) aircraft suitable for regional transport service. The resulting spreadsheet-implemented cost models are semi-empirical and based on Department of Transportation and Army data from actual operations of such aircraft. This paper describes a rationale for selecting cost tech factors without which VTOL is more costly than CTOL by a factor of 10 for maintenance cost and a factor of two for purchase price. The three VTOL designs selected for cost comparisons meet the mission requirement to fly 1,200 nautical miles at 350 knots and 30,000 ft carrying 120 passengers. The lowest cost VTOL design is a large civil tilt rotor (LCTR) aircraft. With cost tech factors applied, the LCTR is reasonably competitive with the Boeing 737-700 when operated in economy regional service following the business model of the selected baseline operation, that of Southwest Airlines.

  16. Box-Cox transformation for QTL mapping.

    PubMed

    Yang, Runqing; Yi, Nengjun; Xu, Shizhong

    2006-01-01

    The maximum likelihood method of QTL mapping assumes that the phenotypic values of a quantitative trait follow a normal distribution. If the assumption is violated, some forms of transformation should be taken to make the assumption approximately true. The Box-Cox transformation is a general transformation method which can be applied to many different types of data. The flexibility of the Box-Cox transformation is due to a variable, called transformation factor, appearing in the Box-Cox formula. We developed a maximum likelihood method that treats the transformation factor as an unknown parameter, which is estimated from the data simultaneously along with the QTL parameters. The method makes an objective choice of data transformation and thus can be applied to QTL analysis for many different types of data. Simulation studies show that (1) Box-Cox transformation can substantially increase the power of QTL detection; (2) Box-Cox transformation can replace some specialized transformation methods that are commonly used in QTL mapping; and (3) applying the Box-Cox transformation to data already normally distributed does not harm the result.

  17. Application of Allan Deviation to Assessing Uncertainties of Continuous-measurement Instruments, and Optimizing Calibration Schemes

    NASA Astrophysics Data System (ADS)

    Jacobson, Gloria; Rella, Chris; Farinas, Alejandro

    2014-05-01

    Technological advancement of instrumentation in atmospheric and other geoscience disciplines over the past decade has lead to a shift from discrete sample analysis to continuous, in-situ monitoring. Standard error analysis used for discrete measurements is not sufficient to assess and compare the error contribution of noise and drift from continuous-measurement instruments, and a different statistical analysis approach should be applied. The Allan standard deviation analysis technique developed for atomic clock stability assessment by David W. Allan [1] can be effectively and gainfully applied to continuous measurement instruments. As an example, P. Werle et al has applied these techniques to look at signal averaging for atmospheric monitoring by Tunable Diode-Laser Absorption Spectroscopy (TDLAS) [2]. This presentation will build on, and translate prior foundational publications to provide contextual definitions and guidelines for the practical application of this analysis technique to continuous scientific measurements. The specific example of a Picarro G2401 Cavity Ringdown Spectroscopy (CRDS) analyzer used for continuous, atmospheric monitoring of CO2, CH4 and CO will be used to define the basics features the Allan deviation, assess factors affecting the analysis, and explore the time-series to Allan deviation plot translation for different types of instrument noise (white noise, linear drift, and interpolated data). In addition, the useful application of using an Allan deviation to optimize and predict the performance of different calibration schemes will be presented. Even though this presentation will use the specific example of the Picarro G2401 CRDS Analyzer for atmospheric monitoring, the objective is to present the information such that it can be successfully applied to other instrument sets and disciplines. [1] D.W. Allan, "Statistics of Atomic Frequency Standards," Proc, IEEE, vol. 54, pp 221-230, Feb 1966 [2] P. Werle, R. Miicke, F. Slemr, "The Limits of Signal Averaging in Atmospheric Trace-Gas Monitoring by Tunable Diode-Laser Absorption Spectroscopy (TDLAS)," Applied Physics, B57, pp 131-139, April 1993

  18. Edmonton obesity staging system among pediatric patients: a validation and obesogenic risk factor analysis.

    PubMed

    Grammatikopoulou, M G; Chourdakis, M; Gkiouras, K; Roumeli, P; Poulimeneas, D; Apostolidou, E; Chountalas, I; Tirodimos, I; Filippou, O; Papadakou-Lagogianni, S; Dardavessis, T

    2018-01-08

    The Edmonton Obesity Staging System for Pediatrics (EOSS-P) is a useful tool, delineating different obesity severity tiers associated with distinct treatment barriers. The aim of the study was to apply the EOSS-P on a Greek pediatric cohort and assess risk factors associated with each stage, compared to normal weight controls. A total of 361 children (2-14 years old), outpatients of an Athenian hospital, participated in this case-control study by forming two groups: the obese (n = 203) and the normoweight controls (n = 158). Anthropometry, blood pressure, blood and biochemical markers, comorbidities and obesogenic lifestyle parameters were recorded and the EOSS-P was applied. Validation of EOSS-P stages was conducted by juxtaposing them with IOTF-defined weight status. Obesogenic risk factors' analysis was conducted by constructing gender-and-age-adjusted (GA) and multivariate logistic models. The majority of obese children were stratified at stage 1 (46.0%), 17.0% were on stage 0, and 37.0% on stage 2. The validation analysis revealed that EOSS-P stages greater than 0 were associated with diastolic blood pressure and levels of glucose, cholesterol, LDL and ALT. Reduced obesity odds were observed among children playing outdoors and increased odds for every screen time hour, both in the GA and in the multivariate analyses (all P < 0.05). Although participation in sports > 2 times/week was associated with reduced obesity odds in the GA analysis (OR = 0.57, 95% CI = 0.33-0.98, P linear = 0.047), it lost its significance in the multivariate analysis (P linear = 0.145). Analogous results were recorded in the analyses of the abovementioned physical activity risk factors for the EOSS-P stages. Linear relationships were observed for fast-food consumption and IOTF-defined obesity and higher than 0 EOSS-P stages. Parental obesity status was associated with all EOSS-P stages and IOTF-defined obesity status. Few outpatients were healthy obese (stage 0), while the majority exhibited several comorbidities. Since each obesity tier entails different impacts to disease management, the study herein highlights modifiable factors facilitating descend to lower stages, and provides insight for designing tailored approaches tackling the high national pediatric obesity rates.

  19. Design factors of femur fracture fixation plates made of shape memory alloy based on the Taguchi method by finite element analysis.

    PubMed

    Ko, Cheolwoong; Yang, Mikyung; Byun, Taemin; Lee, Sang-Wook

    2018-05-01

    This study proposed a way to design femur fracture fixation plates made of shape memory alloy based on computed tomography (CT) images of Korean cadaveric femurs. To this end, 3 major design factors of femur fracture fixation plates (circumference angle, thickness, and inner diameter) were selected based on the contact pressure when a femur fracture fixation plate was applied to a cylinder model using the Taguchi method. Then, the effects of the design factors were analyzed. It was shown that the design factors were statistically significant at a level of p = 0.05 concerning the inner diameter and the thickness. The factors affecting the contact pressure were inner diameter, thickness, and circumference angle, in that order. Particularly, in the condition of Case 9 (inner diameter 27 mm, thickness 2.4 mm, and circumference angle 270°), the max. average contact pressure was 21.721 MPa, while the min. average contact pressure was 3.118 MPa in Case 10 (inner diameter 29 mm, thickness 2.0 mm, and circumference angle 210°). When the femur fracture fixation plate was applied to the cylinder model, the displacement due to external sliding and pulling forces was analyzed. As a result, the displacement in the sliding condition was at max. 3.75 times greater than that in the pulling condition, which indicated that the cohesion strength between the femur fracture fixation plate and the cylinder model was likely to be greater in the pulling condition. When a human femur model was applied, the max. average contact pressure was 10.76 MPa, which was lower than the yield strength of a human femur (108 MPa). In addition, the analysis of the rib behaviors of the femur fracture fixation plate in relation to the recovery effect of the shape memory alloy showed that the rib behaviors varied depending on the arbitrarily curved shapes of the femur sections. Copyright © 2018 John Wiley & Sons, Ltd.

  20. Influence analysis for high-dimensional time series with an application to epileptic seizure onset zone detection

    PubMed Central

    Flamm, Christoph; Graef, Andreas; Pirker, Susanne; Baumgartner, Christoph; Deistler, Manfred

    2013-01-01

    Granger causality is a useful concept for studying causal relations in networks. However, numerical problems occur when applying the corresponding methodology to high-dimensional time series showing co-movement, e.g. EEG recordings or economic data. In order to deal with these shortcomings, we propose a novel method for the causal analysis of such multivariate time series based on Granger causality and factor models. We present the theoretical background, successfully assess our methodology with the help of simulated data and show a potential application in EEG analysis of epileptic seizures. PMID:23354014

  1. Hybrid PV/diesel solar power system design using multi-level factor analysis optimization

    NASA Astrophysics Data System (ADS)

    Drake, Joshua P.

    Solar power systems represent a large area of interest across a spectrum of organizations at a global level. It was determined that a clear understanding of current state of the art software and design methods, as well as optimization methods, could be used to improve the design methodology. Solar power design literature was researched for an in depth understanding of solar power system design methods and algorithms. Multiple software packages for the design and optimization of solar power systems were analyzed for a critical understanding of their design workflow. In addition, several methods of optimization were studied, including brute force, Pareto analysis, Monte Carlo, linear and nonlinear programming, and multi-way factor analysis. Factor analysis was selected as the most efficient optimization method for engineering design as it applied to solar power system design. The solar power design algorithms, software work flow analysis, and factor analysis optimization were combined to develop a solar power system design optimization software package called FireDrake. This software was used for the design of multiple solar power systems in conjunction with an energy audit case study performed in seven Tibetan refugee camps located in Mainpat, India. A report of solar system designs for the camps, as well as a proposed schedule for future installations was generated. It was determined that there were several improvements that could be made to the state of the art in modern solar power system design, though the complexity of current applications is significant.

  2. Seroprevalence and Associated Risk Factors of Toxocariasis among College Students in Taipei City, Taiwan

    PubMed Central

    FU, Chung-Jung; KAO, Cheng-Yan; LEE, Yueh-Lun; LIAO, Chien-Wei; CHEN, Po-Ching; CHUANG, Ting-Wu; WANG, Ying-Chin; CHOU, Chia-Mei; HUANG, Ying-Chie; NAITO, Toshio; FAN, Chia-Kwung

    2015-01-01

    Background: Infection by Toxocara spp. is known to be significantly associated with partial epilepsy. It has become popular for people to raise dogs/cats as pets and consume roasted meat/viscera, and the status of Toxocara spp. infection, epilepsy awareness, and associated risk factors among the general population are currently unknown in Taiwan. Methods: A seroepidemiological investigation among 203 college students (CSs), consisting of 110 males and 93 females with an average age of 21.5 ± 1.2 years, was conducted in 2009 in Taipei City. A Western blot analysis based on excretory-secretory antigens derived from Toxocara canis larvae (TcESs) was applied to determine the positivity of serum immunoglobulin G antibodies. A self-administered questionnaire was also given to obtain information about demographic characteristics, epilepsy awareness, and risk factors. A logistic regression model was applied for the statistical analysis using SPSS software. Results: The overall seropositive rate of Toxocara spp. infection was 8.4% (17/203). As to epilepsy awareness, a non-significantly higher seroprevalence was found in CSs who claimed to "know" about epilepsy compared to those who did not know (P > 0.05). Conclusions: It appears that appropriate educational programs are urgently needed to provide correct knowledge related to the prevention and control measures against Toxocara spp. infections to avoid potential threats by this parasite to the general population in Taiwan. PMID:26622304

  3. [A multilevel model analysis of correlation between population characteristics and work ability of employees].

    PubMed

    Zhang, Lei; Huang, Chunping; Lan, Yajia; Wang, Mianzhen

    2015-12-01

    To analyze the correlation between population characteristics and work ability of employees with a multilevel model, to investigate the important influencing factors for work ability, and to provide a basis for improvement in work ability. Work ability index (WAI)was applied to measure the work ability of 1686 subjects from different companies (n=6). MLwi N2.0 software was applied for two-level variance component model fitting. The WAI of employees showed differences between various companies (χ2=3.378 6, P=0.0660); working years was negatively correlated with WAI (χ2=38.229 2, P=0.0001), and the WAI of the employees with 20 or more working years was 1.63 lower than that of the employees with less than 20 working years; the work ability of manual workers was lower than that of mental-manual workers (χ2=8.2726, P=0.0040), and the work ability showed no significant difference between mental workers and mental-manual workers (χ2=2.086 0, P=0.148 7). From the perspective of probability, the multilevel model analysis reveals the differences in work ability of employees between different companies, and suggests that company, work type, and working years are the important influencing factors for work ability of employees. These factors should be improved and adjusted to protect or enhance the work ability of employees.

  4. Bayesian inference of the number of factors in gene-expression analysis: application to human virus challenge studies

    PubMed Central

    2010-01-01

    Background Nonparametric Bayesian techniques have been developed recently to extend the sophistication of factor models, allowing one to infer the number of appropriate factors from the observed data. We consider such techniques for sparse factor analysis, with application to gene-expression data from three virus challenge studies. Particular attention is placed on employing the Beta Process (BP), the Indian Buffet Process (IBP), and related sparseness-promoting techniques to infer a proper number of factors. The posterior density function on the model parameters is computed using Gibbs sampling and variational Bayesian (VB) analysis. Results Time-evolving gene-expression data are considered for respiratory syncytial virus (RSV), Rhino virus, and influenza, using blood samples from healthy human subjects. These data were acquired in three challenge studies, each executed after receiving institutional review board (IRB) approval from Duke University. Comparisons are made between several alternative means of per-forming nonparametric factor analysis on these data, with comparisons as well to sparse-PCA and Penalized Matrix Decomposition (PMD), closely related non-Bayesian approaches. Conclusions Applying the Beta Process to the factor scores, or to the singular values of a pseudo-SVD construction, the proposed algorithms infer the number of factors in gene-expression data. For real data the "true" number of factors is unknown; in our simulations we consider a range of noise variances, and the proposed Bayesian models inferred the number of factors accurately relative to other methods in the literature, such as sparse-PCA and PMD. We have also identified a "pan-viral" factor of importance for each of the three viruses considered in this study. We have identified a set of genes associated with this pan-viral factor, of interest for early detection of such viruses based upon the host response, as quantified via gene-expression data. PMID:21062443

  5. Factors affecting survival outcomes of patients with non-metastatic Ewing's sarcoma family tumors in the spine: a retrospective analysis of 63 patients in a single center.

    PubMed

    Wan, Wei; Lou, Yan; Hu, Zhiqi; Wang, Ting; Li, Jinsong; Tang, Yu; Wu, Zhipeng; Xu, Leqin; Yang, Xinghai; Song, Dianwen; Xiao, Jianru

    2017-01-01

    Little information has been published in the literature regarding survival outcomes of patients with Ewing's sarcoma family tumors (ESFTs) of the spine. The purpose of this study is to explore factors that may affect the prognosis of patients with non-metastatic spinal ESFTs. A retrospective analysis of survival outcomes was performed in patients with non-metastatic spinal ESFTs. Univariate and multivariate analyses were employed to identify prognostic factors for recurrence and survival. Recurrence-free survival (RFS) and overall survival (OS) were defined as the date of surgery to the date of local relapse and death. Kaplan-Meier methods were applied to estimate RFS and OS. Log-rank test was used to analyze single factors for RFS and OS. Factors with p values ≤0.1 were subjected to multivariate analysis. A total of 63 patients with non-metastatic spinal ESFTs were included in this study. The mean follow-up period was 35.1 months (range 1-155). Postoperative recurrence was detected in 25 patients, and distant metastasis and death occurred in 22 and 36 patients respectively. The result of multivariate analysis suggested that age older than 25 years and neoadjuvant chemotherapy were favorable independent prognostic factors for RFS and OS. In addition, total en-bloc resection, postoperative chemotherapy, radiotherapy and non-distant metastasis were favorable independent prognostic factors for OS. Age older than 25 years and neoadjuvant chemotherapy are favorable prognostic factors for both RFS and OS. In addition, total en-bloc resection, postoperative chemotherapy, radiotherapy and non-distant metastasis are closely associated with favorable survival.

  6. [Core factors of schizophrenia structure based on PANSS and SAPS/SANS results. Discerning and head-to-head comparisson of PANSS and SASPS/SANS validity].

    PubMed

    Masiak, Marek; Loza, Bartosz

    2004-01-01

    A lot of inconsistencies across dimensional studies of schizophrenia(s) are being unveiled. These problems are strongly related to the methodological aspects of collecting data and specific statistical analyses. Psychiatrists have developed lots of psychopathological models derived from analytic studies based on SAPS/SANS (the Scale for the Assessment of Positive Symptoms/the Scale for the Assessment of Negative Symptoms) and PANSS (The Positive and Negative Syndrome Scale). The unique validation of parallel two independent factor models was performed--ascribed to the same illness and based on different diagnostic scales--to investigate indirect methodological causes of clinical discrepancies. 100 newly admitted patients (mean age--33.5, 18-45, males--64, females--36, hospitalised on average 5.15 times) with paranoid schizophrenia (according to ICD-10) were scored and analysed using PANSS and SAPS/SANS during psychotic exacerbation. All patients were treated with neuroleptics of various kinds with 410mg equivalents of chlorpromazine (atypicals:typicals --> 41:59). Factor analyses were applied to basic results (with principal component analysis, normalised varimax rotation). Investing the cross-model validity, canonical analysis was applied. Models of schizophrenia varied from 3 to 5 factors. PANSS model included: positive, negative, disorganisation, cognitive and depressive components and SAPS/SANS model was dominated by positive, negative and disorganisation factors. The SAPS/SANS accounted for merely 48% of the PANSS common variances. The SAPS/SANS combined measurement preferentially (67% of canonical variance) targeted positive-negative dichotomy. Respectively, PANSS shared positive-negative phenomenology in 35% of its own variance. The general concept of five-dimensionality in paranoid schizophrenia looks clinically more heuristic and statistically more stabilised.

  7. Local-scale topoclimate effects on treeline elevations: a country-wide investigation of New Zealand's southern beech treelines.

    PubMed

    Case, Bradley S; Buckley, Hannah L

    2015-01-01

    Although treeline elevations are limited globally by growing season temperature, at regional scales treelines frequently deviate below their climatic limit. The cause of these deviations relate to a host of climatic, disturbance, and geomorphic factors that operate at multiple scales. The ability to disentangle the relative effects of these factors is currently hampered by the lack of reliable topoclimatic data, which describe how regional climatic characteristics are modified by topographic effects in mountain areas. In this study we present an analysis of the combined effects of local- and regional-scale factors on southern beech treeline elevation variability at 28 study areas across New Zealand. We apply a mesoscale atmospheric model to generate local-scale (200 m) meteorological data at these treelines and, from these data, we derive a set of topoclimatic indices that reflect possible detrimental and ameliorative influences on tree physiological functioning. Principal components analysis of meteorological data revealed geographic structure in how study areas were situated in multivariate space along gradients of topoclimate. Random forest and conditional inference tree modelling enabled us to tease apart the relative effects of 17 explanatory factors on local-scale treeline elevation variability. Overall, modelling explained about 50% of the variation in treeline elevation variability across the 28 study areas, with local landform and topoclimatic effects generally outweighing those from regional-scale factors across the 28 study areas. Further, the nature of the relationships between treeline elevation variability and the explanatory variables were complex, frequently non-linear, and consistent with the treeline literature. To our knowledge, this is the first study where model-generated meteorological data, and derived topoclimatic indices, have been developed and applied to explain treeline variation. Our results demonstrate the potential of such an approach for ecological research in mountainous environments.

  8. Local-scale topoclimate effects on treeline elevations: a country-wide investigation of New Zealand’s southern beech treelines

    PubMed Central

    Buckley, Hannah L.

    2015-01-01

    Although treeline elevations are limited globally by growing season temperature, at regional scales treelines frequently deviate below their climatic limit. The cause of these deviations relate to a host of climatic, disturbance, and geomorphic factors that operate at multiple scales. The ability to disentangle the relative effects of these factors is currently hampered by the lack of reliable topoclimatic data, which describe how regional climatic characteristics are modified by topographic effects in mountain areas. In this study we present an analysis of the combined effects of local- and regional-scale factors on southern beech treeline elevation variability at 28 study areas across New Zealand. We apply a mesoscale atmospheric model to generate local-scale (200 m) meteorological data at these treelines and, from these data, we derive a set of topoclimatic indices that reflect possible detrimental and ameliorative influences on tree physiological functioning. Principal components analysis of meteorological data revealed geographic structure in how study areas were situated in multivariate space along gradients of topoclimate. Random forest and conditional inference tree modelling enabled us to tease apart the relative effects of 17 explanatory factors on local-scale treeline elevation variability. Overall, modelling explained about 50% of the variation in treeline elevation variability across the 28 study areas, with local landform and topoclimatic effects generally outweighing those from regional-scale factors across the 28 study areas. Further, the nature of the relationships between treeline elevation variability and the explanatory variables were complex, frequently non-linear, and consistent with the treeline literature. To our knowledge, this is the first study where model-generated meteorological data, and derived topoclimatic indices, have been developed and applied to explain treeline variation. Our results demonstrate the potential of such an approach for ecological research in mountainous environments. PMID:26528407

  9. The patient work system: An analysis of self-care performance barriers among elderly heart failure patients and their informal caregivers

    PubMed Central

    Holden, Richard J.; Schubert, Christiane C.; Mickelson, Robin S.

    2014-01-01

    Human factors and ergonomics approaches have been successfully applied to study and improve the work performance of healthcare professionals. However, there has been relatively little work in “patient-engaged human factors,” or the application of human factors to the health-related work of patients and other nonprofessionals. This study applied a foundational human factors tool, the systems model, to investigate the barriers to self-care performance among chronically ill elderly patients and their informal (family) caregivers. A Patient Work System model was developed to guide the collection and analysis of interviews, surveys, and observations of patients with heart failure (n=30) and their informal caregivers (n=14). Iterative analyses revealed the nature and prevalence of self-care barriers across components of the Patient Work System. Person-related barriers were common and stemmed from patients’ biomedical conditions, limitations, knowledge deficits, preferences, and perceptions as well as the characteristics of informal caregivers and healthcare professionals. Task barriers were also highly prevalent and included task difficulty, timing, complexity, ambiguity, conflict, and undesirable consequences. Tool barriers were related to both availability and access of tools and technologies and their design, usability, and impact. Context barriers were found across three domains—physical-spatial, social-cultural, and organizational—and multiple “spaces” such as “at home,” “on the go,” and “in the community.” Barriers often stemmed not from single factors but from the interaction of several work system components. Study findings suggest the need to further explore multiple actors, context, and interactions in the patient work system during research and intervention design, as well as the need to develop new models and measures for studying patient and family work. PMID:25479983

  10. The patient work system: an analysis of self-care performance barriers among elderly heart failure patients and their informal caregivers.

    PubMed

    Holden, Richard J; Schubert, Christiane C; Mickelson, Robin S

    2015-03-01

    Human factors and ergonomics approaches have been successfully applied to study and improve the work performance of healthcare professionals. However, there has been relatively little work in "patient-engaged human factors," or the application of human factors to the health-related work of patients and other nonprofessionals. This study applied a foundational human factors tool, the systems model, to investigate the barriers to self-care performance among chronically ill elderly patients and their informal (family) caregivers. A Patient Work System model was developed to guide the collection and analysis of interviews, surveys, and observations of patients with heart failure (n = 30) and their informal caregivers (n = 14). Iterative analyses revealed the nature and prevalence of self-care barriers across components of the Patient Work System. Person-related barriers were common and stemmed from patients' biomedical conditions, limitations, knowledge deficits, preferences, and perceptions as well as the characteristics of informal caregivers and healthcare professionals. Task barriers were also highly prevalent and included task difficulty, timing, complexity, ambiguity, conflict, and undesirable consequences. Tool barriers were related to both availability and access of tools and technologies and their design, usability, and impact. Context barriers were found across three domains-physical-spatial, social-cultural, and organizational-and multiple "spaces" such as "at home," "on the go," and "in the community." Barriers often stemmed not from single factors but from the interaction of several work system components. Study findings suggest the need to further explore multiple actors, contexts, and interactions in the patient work system during research and intervention design, as well as the need to develop new models and measures for studying patient and family work. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  11. Psychometric properties of the Persian version of the Time to Relapse Questionnaire (TRQ) in substance use disorder.

    PubMed

    Khazaee-Pool, Maryam; Moridi, Minoo; Ponnet, Koen; Turner, Nigel; Pashaei, Tahereh

    2016-11-01

    Predicting time to relapse provides an opportunity for the development of relapse prevention interventions in drug users. The aim of the present study was to describe the development of the Persian version of the 9-item Time to Relapse Questionnaire (TRQ) and to evaluate its psychometric properties in an Iranian sample of treatment-seeking individuals with substance dependence (n = 150). The forward-backward method was used to translate the TRQ scale from English into Persian. After linguistic validation and a pilot check, a cross-sectional study was performed, and psychometric properties of the Iranian version of the questionnaire were assessed. The reliability was evaluated by Cronbach's alpha and test-retest analyses. In addition, the factor structure of the scale was extracted by applying confirmatory factor analysis. The mean age of participants was 40.52 (SD = 11.30) years. The mean scores for the content validity index (CVI) and the content validity ratio (CVR) were 0.93 and 0.81, respectively. A confirmatory factor analysis (CFA) demonstrated that the three-factor model of the TRQ was a good fit for the data and thus replicated the factor structure of the original English language TRQ. Cronbach's alpha presented good internal consistency (alpha = 0.76), and test-retest reliability of the TRQ instrument with 2-week intervals was appropriate (ICC = 0.84). The findings demonstrate that the Persian version of the TRQ is a reliable and valid scale for measuring time to relapse in Iranian drug users. The TRQ can be applied at the start of treatment so that clinical interventions can be targeted toward the different relapse styles.

  12. The use of topical honey in the treatment of corneal abrasions and endotoxin-induced keratitis in an animal model.

    PubMed

    Uwaydat, Sami; Jha, Purushottam; Tytarenko, Ruslana; Brown, Harry; Wiggins, Michael; Bora, Puran S; Bora, Nalini S

    2011-09-01

     To investigate the effect of topically applied honey on intact corneas, surgically induced corneal abrasions and endotoxin induced keratitis. The effect of honey on the cornea was investigated by application of honey on intact corneas, wounded corneas and endotoxin-induced keratitis in Lewis rats. The corneas were wounded by creating an epithelial defect using a surgical blade, and the keratitis was induced by topically applying Pseudomonas aeruginosa endotoxin to scarified corneas. After treatment rats were sacrificed and cornea harvested in each case. Corneas were processed for paraffin embedding for histological and immuno-fluorescence staining. Corneas were also harvested and processed for total ribonucleic acid (RNA) isolation for reverse transcriptase-polymerase chain reaction (RT-PCR) analysis for various growth factors and inflammatory chemokines/cytokines).  Histological analysis revealed that no inflammation or morphological changes occurred after honey treatment in naive intact corneas. Vascular endothelial growth factor (VEGF) levels were also not altered after honey treatment. Topical application of honey to injured corneas resulted in faster epithelial healing and decreased expression of VEGF, transforming growth factor beta (TGF-β), interferon gamma (IFN-γ), interleukin 12 (IL-12) and tumor necrosis factor alpha (TNF-α) in injured corneas. Our results also established that honey treatment reduced the inflammation in endotoxin-induced keratitis by reducing the levels of angiogenic factors (VEGF and TGF-β), inflammatory cytokines (IL-12) and chemokines (CC chemokine receptor 5(CCR-5)).  Short term use of honey on intact corneas can be safe. Honey has anti-angiogenic and anti-inflammatory properties that can be explored in several corneal inflammatory and infectious conditions.

  13. Review and analysis of global agricultural N₂O emissions relevant to the UK.

    PubMed

    Buckingham, S; Anthony, S; Bellamy, P H; Cardenas, L M; Higgins, S; McGeough, K; Topp, C F E

    2014-07-15

    As part of a UK government funded research project to update the UK N2O inventory methodology, a systematic review of published nitrous oxide (N2O) emission factors was carried out of non-UK research, for future comparison and synthesis with the UK measurement based evidence base. The aim of the study is to assess how the UK IPCC default emission factor for N2O emissions derived from synthetic or organic fertiliser inputs (EF1) compares to international values reported in published literature. The availability of data for comparing and/or refining the UK IPCC default value and the possibility of analysing sufficient auxiliary data to propose a Tier 2 EF1 reporting strategy is evaluated. The review demonstrated a lack of consistency in reporting error bounds for fertiliser-derived EFs and N2O flux data with 8% and 44% of publications reporting EF and N2O flux error bounds respectively. There was also poor description of environmental (climate and soil) and experimental design auxiliary data. This is likely to be due to differences in study objectives, however potential improvements to soil parameter reporting are proposed. The review demonstrates that emission factors for agricultural-derived N2O emissions ranged -0.34% to 37% showing high variation compared to the UK Tier 1 IPCC EF1 default values of 1.25% (IPCC 1996) and 1% (IPPC 2006). However, the majority (83%) of EFs reported for UK-relevant soils fell within the UK IPCC EF1 uncertainty range of 0.03% to 3%. Residual maximum likelihood (REML) analysis of the data collated in the review showed that the type and rate of fertiliser N applied and soil type were significant factors influencing EFs reported. Country of emission, the length of the measurement period, the number of splits, the crop type, pH and SOC did not have a significant impact on N2O emissions. A subset of publications where sufficient data was reported for meta-analysis to be conducted was identified. Meta-analysis of effect sizes of 41 treatments demonstrated that the application of fertiliser has a significant effect on N2O emissions in comparison to control plots and that emission factors were significantly different to zero. However no significant relationships between the quantity of fertiliser applied and the effect size of the amount of N2O emitted from fertilised plots compared to control plots were found. Annual addition of fertiliser of 35 to 557 kg N/ha gave a mean increase in emissions of 2.02 ± 0.28 g N2O/ha/day compared to control treatments (p<0.01). Emission factors were significantly different from zero, with a mean emission factor estimated directly from the meta analysis of 0.17 ± 0.02%. This is lower than the IPCC 2006 Tier 1 EF1 value of 1% but falling within the uncertainty bound for the IPCC 2006 Tier 1 EF1 (0.03% to 3%). As only a small number of papers were viable for meta analysis to be conducted due to lack of reporting of the key controlling factors, the estimates of EF in this paper cannot include the true variability under conditions similar to the UK. Review-derived EFs of 0.34% to 37% and mean EF from meta-analysis of 0.17 ± 0.02% highlight variability in reporting EFs depending on the method applied and sample size. A protocol of systematic reporting of N2O emissions and key auxiliary parameters in publications across disciplines is proposed. If adopted this would strengthen the community to inform IPCC Tier 2 reporting development and reduce the uncertainty surrounding reported UK N2O emissions. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Development of regionalized SPFs for two-lane rural roads in Pennsylvania.

    PubMed

    Li, Lingyu; Gayah, Vikash V; Donnell, Eric T

    2017-11-01

    The American Association of State Highway and Transportation Officials' Highway Safety Manual (HSM) contains safety performance functions (SPFs) to predict annual crash frequencies for several roadway types. When applying these SPFs in a jurisdiction whose data were not used to develop the SPF, a calibration factor can be applied to adjust the expected crash frequency estimate to statewide or local conditions. Alternatively, the HSM suggests that transportation agencies may develop their own SPFs in lieu of applying the calibration factor to the HSM SPFs. However, the HSM does not provide guidance on the appropriate level of regionalization that should be adopted for either method, even though safety performance may vary considerably within a state. In light of this, the present study considers the development of local or regionalized SPFs for two-lane rural highways within the Commonwealth of Pennsylvania. Three regionalization levels were considered: statewide, engineering district and individual counties. The expected crash frequency for each level of regionalization was compared to the reported crash frequency over an eight-year analysis period. The results indicate that district-level SPFs with county-level adjustment factors provide better predictive accuracy than the development of a statewide SPF or application of the HSM-calibrated SPF. The findings suggest that there are significant differences in safety performance across engineering districts within Pennsylvania. As such, other state transportation agencies developing SPFs or using calibration factors may also consider how variations across jurisdictions will affect predicted crash frequencies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. [Factors related to the scientific production of gastroenterologists in Lima-Peru].

    PubMed

    Parra Pérez, V; Monge Salgado, E; Vildósola Gonzales, H

    2009-01-01

    The biomedical investigation in Peru is limited; among the implicated factors we have the reduced per-capita expense in investigation, the disperse efforts and the low communication between the investigations and the social productive activities. To determinate the personal, professional and academic factors related with the scientific production of the medical gastroenterologists that work in province Lima. Co-relational, observational, comparative, transversal and retrospective studies that had happened in between march 2007 and april 2008. Was elaborated a survey containing the variables of the investigation which was applied autoadministered to the gastroenterologists. Using bivaried and multivaried, were identified factors related with the scientific production of the gastroenterologist. The bivaried analysis has found, as related factors with the scientific production: Teaching, type of bibliographic research, degree of comprehension of the scientific article, facilities for the investigation at the job, subscription at the scientific magazine, to belong to the scientific society and the number of employments. The multivaried analysis found the previous factors but teaching and subscription to the scientific magazine, related with the scientific production. Those gastroenterologists that, despite being in contact with factors that impede the development of the investigation, had overcome the local negative influence and emerge, deserve consideration, because is on them were we can recognize factors that favor the investigation labor.

  16. Non-parametric causality detection: An application to social media and financial data

    NASA Astrophysics Data System (ADS)

    Tsapeli, Fani; Musolesi, Mirco; Tino, Peter

    2017-10-01

    According to behavioral finance, stock market returns are influenced by emotional, social and psychological factors. Several recent works support this theory by providing evidence of correlation between stock market prices and collective sentiment indexes measured using social media data. However, a pure correlation analysis is not sufficient to prove that stock market returns are influenced by such emotional factors since both stock market prices and collective sentiment may be driven by a third unmeasured factor. Controlling for factors that could influence the study by applying multivariate regression models is challenging given the complexity of stock market data. False assumptions about the linearity or non-linearity of the model and inaccuracies on model specification may result in misleading conclusions. In this work, we propose a novel framework for causal inference that does not require any assumption about a particular parametric form of the model expressing statistical relationships among the variables of the study and can effectively control a large number of observed factors. We apply our method in order to estimate the causal impact that information posted in social media may have on stock market returns of four big companies. Our results indicate that social media data not only correlate with stock market returns but also influence them.

  17. Figure-Ground Segmentation Using Factor Graphs

    PubMed Central

    Shen, Huiying; Coughlan, James; Ivanchenko, Volodymyr

    2009-01-01

    Foreground-background segmentation has recently been applied [26,12] to the detection and segmentation of specific objects or structures of interest from the background as an efficient alternative to techniques such as deformable templates [27]. We introduce a graphical model (i.e. Markov random field)-based formulation of structure-specific figure-ground segmentation based on simple geometric features extracted from an image, such as local configurations of linear features, that are characteristic of the desired figure structure. Our formulation is novel in that it is based on factor graphs, which are graphical models that encode interactions among arbitrary numbers of random variables. The ability of factor graphs to express interactions higher than pairwise order (the highest order encountered in most graphical models used in computer vision) is useful for modeling a variety of pattern recognition problems. In particular, we show how this property makes factor graphs a natural framework for performing grouping and segmentation, and demonstrate that the factor graph framework emerges naturally from a simple maximum entropy model of figure-ground segmentation. We cast our approach in a learning framework, in which the contributions of multiple grouping cues are learned from training data, and apply our framework to the problem of finding printed text in natural scenes. Experimental results are described, including a performance analysis that demonstrates the feasibility of the approach. PMID:20160994

  18. Analyzing injury severity factors at highway railway grade crossing accidents involving vulnerable road users: A comparative study.

    PubMed

    Ghomi, Haniyeh; Bagheri, Morteza; Fu, Liping; Miranda-Moreno, Luis F

    2016-11-16

    The main objective of this study is to identify the main factors associated with injury severity of vulnerable road users (VRUs) involved in accidents at highway railroad grade crossings (HRGCs) using data mining techniques. This article applies an ordered probit model, association rules, and classification and regression tree (CART) algorithms to the U.S. Federal Railroad Administration's (FRA) HRGC accident database for the period 2007-2013 to identify VRU injury severity factors at HRGCs. The results show that train speed is a key factor influencing injury severity. Further analysis illustrated that the presence of illumination does not reduce the severity of accidents for high-speed trains. In addition, there is a greater propensity toward fatal accidents for elderly road users compared to younger individuals. Interestingly, at night, injury accidents involving female road users are more severe compared to those involving males. The ordered probit model was the primary technique, and CART and association rules act as the supporter and identifier of interactions between variables. All 3 algorithms' results consistently show that the most influential accident factors are train speed, VRU age, and gender. The findings of this research could be applied for identifying high-risk hotspots and developing cost-effective countermeasures targeting VRUs at HRGCs.

  19. Coating process optimization through in-line monitoring for coating weight gain using Raman spectroscopy and design of experiments.

    PubMed

    Kim, Byungsuk; Woo, Young-Ah

    2018-05-30

    In this study the authors developed a real-time Process Analytical Technology (PAT) of a coating process by applying in-line Raman spectroscopy to evaluate the coating weight gain, which is a quantitative analysis of the film coating layer. The wide area illumination (WAI) Raman probe was connected to the pan coater for real-time monitoring of changes in the weight gain of coating layers. Under the proposed in-line Raman scheme, a non-contact, non-destructive analysis was performed using WAI Raman probes with a spot size of 6 mm. The in-line Raman probe maintained a focal length of 250 mm, and a compressed air line was designed to protect the lens surface from spray droplets. The Design of Experiment (DOE) was applied to identify factors affecting the Raman spectra background of laser irradiation. The factors selected for DOE were the strength of compressed air connected to the probe, and the shielding of light by the transparent door connecting the probe to the pan coater. To develop a quantitative model, partial least squares (PLS) models as multivariate calibration were developed based on the three regions showing the specificity of TiO 2 individually or in combination. For the three single peaks (636 cm -1 , 512 cm -1 , 398 cm -1 ), least squares method (LSM) was applied to develop three univariate quantitative analysis models. One of best multivariate quantitative model having a factor of 1 gave the lowest RMSEP of 0.128, 0.129, and 0.125, respectively for prediction batches. When LSM was applied to the single peak at 636 cm -1 , the univariate quantitative model with an R 2 of 0.9863, slope of 0.5851, and y-intercept of 0.8066 had the lowest RMSEP of 0.138, 0.144, and 0.153, respectively for prediction batches. The in-line Raman spectroscopic method for the analysis of coating weight gain was verified by considering system suitability and parameters such as specificity, range, linearity, accuracy, and precision in accordance with ICH Q2 regarding method validation. The proposed in-line Raman spectroscopy can be utilized as a PAT for product quality assurance as it offers real-time monitoring of quantitative changes in coating weight gain and process end-points during the film coating process. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Study of single nucleotide polymorphisms of tumour necrosis factors and HSP genes in nasopharyngeal carcinoma in North East India.

    PubMed

    Lakhanpal, Meena; Singh, Laishram Chandreshwor; Rahman, Tashnin; Sharma, Jagnnath; Singh, M Madhumangal; Kataki, Amal Chandra; Verma, Saurabh; Pandrangi, Santhi Latha; Singh, Y Mohan; Wajid, Saima; Kapur, Sujala; Saxena, Sunita

    2016-01-01

    Nasopharyngeal carcinoma (NPC) is an epithelial tumour with a distinctive racial and geographical distribution. High incidence of NPC has been reported from China, Southeast Asia, and northeast (NE) region of India. The immune mechanism plays incredibly role in pathogenesis of NPC. Tumour necrosis factors (TNFs) and heat shock protein 70 (HSP 70) constitute significant components of innate as well as adaptive host immunity. Multi-analytical approaches including logistic regression (LR), classification and regression tree (CART) and multifactor dimensionality reduction (MDR) were applied in 120 NPC cases and 100 controls to explore high order interactions among TNF-α (-308 G>A), TNF β (+252 A>G), HSP 70-1 (+190 G>C), HSP 70-hom (+2437 T>C) genes and environmental risk factors. TNF β was identified as the primary etiological factor by all three analytical approaches. Individual analysis of results showed protective effect of TNF β GG genotype (adjusted odds ratio (OR2) = 0.27, 95 % CI = 0.125-0.611, P = 0.001), HSP 70 (+2437) CC genotype (OR2 = 0.17, 95 % CI = 0.0430.69, P = 0.013), while AG genotype of TNF β was found significantly associated with risk of NPC (OR2 = 1.97, 95 % CI = 1.019-3.83, P = 0.04). Analysis of environmental factors demonstrated association of alcohol consumption, living in mud houses and use of firewood for cooking as major risk factors for NPC. Individual haplotype association analysis showed significant risk associated with GTGA haplotype (OR = 68.61, 95 % CI = 2.47-190.37, P = 0.013) while a protective effect with CCAA and GCGA haplotypes (OR = 0.19, 95 % CI = 0.05-0.75, P = 0.019; OR = 0.01 95 % CI = 0.05-0.30, P = 0.007). The multi-analytical approaches applied in this study helped in identification of distinct gene-gene and gene-environment interactions significant in risk assessment of NPC.

  1. Assessing an organizational culture instrument based on the Competing Values Framework: Exploratory and confirmatory factor analyses

    PubMed Central

    Helfrich, Christian D; Li, Yu-Fang; Mohr, David C; Meterko, Mark; Sales, Anne E

    2007-01-01

    Background The Competing Values Framework (CVF) has been widely used in health services research to assess organizational culture as a predictor of quality improvement implementation, employee and patient satisfaction, and team functioning, among other outcomes. CVF instruments generally are presented as well-validated with reliable aggregated subscales. However, only one study in the health sector has been conducted for the express purpose of validation, and that study population was limited to hospital managers from a single geographic locale. Methods We used exploratory and confirmatory factor analyses to examine the underlying structure of data from a CVF instrument. We analyzed cross-sectional data from a work environment survey conducted in the Veterans Health Administration (VHA). The study population comprised all staff in non-supervisory positions. The survey included 14 items adapted from a popular CVF instrument, which measures organizational culture according to four subscales: hierarchical, entrepreneurial, team, and rational. Results Data from 71,776 non-supervisory employees (approximate response rate 51%) from 168 VHA facilities were used in this analysis. Internal consistency of the subscales was moderate to strong (α = 0.68 to 0.85). However, the entrepreneurial, team, and rational subscales had higher correlations across subscales than within, indicating poor divergent properties. Exploratory factor analysis revealed two factors, comprising the ten items from the entrepreneurial, team, and rational subscales loading on the first factor, and two items from the hierarchical subscale loading on the second factor, along with one item from the rational subscale that cross-loaded on both factors. Results from confirmatory factor analysis suggested that the two-subscale solution provides a more parsimonious fit to the data as compared to the original four-subscale model. Conclusion This study suggests that there may be problems applying conventional CVF subscales to non-supervisors, and underscores the importance of assessing psychometric properties of instruments in each new context and population to which they are applied. It also further highlights the challenges management scholars face in assessing organizational culture in a reliable and comparable way. More research is needed to determine if the emergent two-subscale solution is a valid or meaningful alternative and whether these findings generalize beyond VHA. PMID:17459167

  2. Finite element analysis on a medical implant.

    PubMed

    Semenescu, Augustin; Radu-Ioniță, Florentina; Mateș, Ileana Mariana; Bădică, Petre; Batalu, Nicolae Dan; Negoita, Olivia Doina; Purcarea, Victor Lorin

    2016-01-01

    Several studies have shown a tight connection between several ocular pathologies and an increased risk of hip fractures due to falling, especially among elderly patients. The total replacement of the hip joint is a major surgical intervention that aims to restore the function of the affected hip by various factors, such as arthritis, injures, and others. A corkscrew-like femoral stem was designed in order to preserve the bone stock and to prevent the occurrence of iatrogenic fractures during the hammering of the implant. In this paper, the finite element analysis for the proposed design was applied, considering different loads and three types of materials. A finite element analysis is a powerful tool to simulate, optimize, design, and select suitable materials for new medical implants. The results showed that the best scenario was for Ti6Al4V alloy, although Ti and 316L stainless steel had a reasonable high safety factor.

  3. Sparse non-negative matrix factorizations via alternating non-negativity-constrained least squares for microarray data analysis.

    PubMed

    Kim, Hyunsoo; Park, Haesun

    2007-06-15

    Many practical pattern recognition problems require non-negativity constraints. For example, pixels in digital images and chemical concentrations in bioinformatics are non-negative. Sparse non-negative matrix factorizations (NMFs) are useful when the degree of sparseness in the non-negative basis matrix or the non-negative coefficient matrix in an NMF needs to be controlled in approximating high-dimensional data in a lower dimensional space. In this article, we introduce a novel formulation of sparse NMF and show how the new formulation leads to a convergent sparse NMF algorithm via alternating non-negativity-constrained least squares. We apply our sparse NMF algorithm to cancer-class discovery and gene expression data analysis and offer biological analysis of the results obtained. Our experimental results illustrate that the proposed sparse NMF algorithm often achieves better clustering performance with shorter computing time compared to other existing NMF algorithms. The software is available as supplementary material.

  4. Modeling and Analysis of Multidiscipline Research Teams at NASA Langley Research Center: A Systems Thinking Approach

    NASA Technical Reports Server (NTRS)

    Waszak, Martin R.; Barthelemy, Jean-Francois; Jones, Kenneth M.; Silcox, Richard J.; Silva, Walter A.; Nowaczyk, Ronald H.

    1998-01-01

    Multidisciplinary analysis and design is inherently a team activity due to the variety of required expertise and knowledge. As a team activity, multidisciplinary research cannot escape the issues that affect all teams. The level of technical diversity required to perform multidisciplinary analysis and design makes the teaming aspects even more important. A study was conducted at the NASA Langley Research Center to develop a model of multidiscipline teams that can be used to help understand their dynamics and identify key factors that influence their effectiveness. The study sought to apply the elements of systems thinking to better understand the factors, both generic and Langley-specific, that influence the effectiveness of multidiscipline teams. The model of multidiscipline research teams developed during this study has been valuable in identifying means to enhance team effectiveness, recognize and avoid problem behaviors, and provide guidance for forming and coordinating multidiscipline teams.

  5. A Bibliometric History of the Journal of Psychology Between 1936 and 2015.

    PubMed

    Tur-Porcar, Ana; Mas-Tur, Alicia; Merigó, José M; Roig-Tierno, Norat; Watt, John

    2018-05-19

    The Journal of Psychology: Interdisciplinary and Applied is a leading international journal in psychology dating back to 1935. This study examines its publications since its creation utilizing a bibliometric analysis. The primary objective is to provide a complete overview of the key factors affecting the journal. This analysis includes such key issues as the publication and citation structure of the journal, its most cited articles, and the leading authors, institutions, and countries referenced in the journal. The work uses the Scopus database to classify the bibliographic material. Additionally, the analysis provides a graphical mapping of the bibliographic data by using visualization of similarities viewer software. This software uses several bibliometric techniques including co-citation, bibliographic coupling and co-occurrence of keywords. The Journal of Psychology is strongly connected to most of the current leading journals in psychology, and currently has a 5-year impact factor of 1.77 (Thomson Reuters, 2015 Journal Citation Reports).

  6. A meta-analysis of factors affecting trust in human-robot interaction.

    PubMed

    Hancock, Peter A; Billings, Deborah R; Schaefer, Kristin E; Chen, Jessie Y C; de Visser, Ewart J; Parasuraman, Raja

    2011-10-01

    We evaluate and quantify the effects of human, robot, and environmental factors on perceived trust in human-robot interaction (HRI). To date, reviews of trust in HRI have been qualitative or descriptive. Our quantitative review provides a fundamental empirical foundation to advance both theory and practice. Meta-analytic methods were applied to the available literature on trust and HRI. A total of 29 empirical studies were collected, of which 10 met the selection criteria for correlational analysis and 11 for experimental analysis. These studies provided 69 correlational and 47 experimental effect sizes. The overall correlational effect size for trust was r = +0.26,with an experimental effect size of d = +0.71. The effects of human, robot, and environmental characteristics were examined with an especial evaluation of the robot dimensions of performance and attribute-based factors. The robot performance and attributes were the largest contributors to the development of trust in HRI. Environmental factors played only a moderate role. Factors related to the robot itself, specifically, its performance, had the greatest current association with trust, and environmental factors were moderately associated. There was little evidence for effects of human-related factors. The findings provide quantitative estimates of human, robot, and environmental factors influencing HRI trust. Specifically, the current summary provides effect size estimates that are useful in establishing design and training guidelines with reference to robot-related factors of HRI trust. Furthermore, results indicate that improper trust calibration may be mitigated by the manipulation of robot design. However, many future research needs are identified.

  7. Analysis of IFE, EFE and QSPM matrix on business development strategy

    NASA Astrophysics Data System (ADS)

    Zulkarnain, A.; Wahyuningtias, D.; Putranto, T. S.

    2018-03-01

    IFE matrix, EFE matrix, and QSPM matrix are business strategy tools that can be used to identify the threat, opportunity, weakness, strength as internal, external business factors. The goal of Danti’s Deli Bakery is to provide pastry product and distribute to other food and beverage outlet all around Jakarta. Thus, Danti’s Deli Bakery requires development strategy in order to win the tight competition. Applied descriptive research and data collected from focus group discussion, questionnaire, interview, observation and literature review. The objectives of this paper are (1) to identify and evaluate internal and external factors, (2) to formulate alternative strategy toward business development program, and (3) to give effective recommendation. The result shows that Danti’s Deli Bakery should apply product differentiation strategy. Implementation of this study is providing the recommendation for pastry and bakery industry to establish a successful business.

  8. Estimation of Stress Concentration Factor of Plate with Hole using Piezoelectric Actuator and Finite Element Method

    NASA Astrophysics Data System (ADS)

    Abuzaid, A.; Hrairi, M.; Shaik Dawood, M. S. I.

    2017-03-01

    In this paper, the effect of piezoelectric actuators placed above a circular hole of a rectangular plate subjected to uniform uniaxial tension is studied. The core idea is to investigate the stress (compression/tension) produced by the piezoelectric actuators on the stress distribution around the hole and along the width of the host plate. For this purpose, Finite Element Analysis (FEA) was carried out through parametric study in ANSYS software. The results demonstrated that the positive electric field would decrease and change the state of the stress distribution along the width of the host plate in contrast to the negative applied electric filed which increases the stress distribution smoothly without affecting its behaviour. The results also indicated that the reduction of the stress concentration factor increases with the decrease of the ratio (D/W) for the same applied positive electric field.

  9. The Basic Psychological Needs at Work Scale: Measurement Invariance between Canada and France.

    PubMed

    Brien, Maryse; Forest, Jacques; Mageau, Geneviève A; Boudrias, Jean-Sébastien; Desrumaux, Pascale; Brunet, Luc; Morin, Estelle M

    2012-07-01

    The purpose of this study is to develop and validate the Basic Psychological Needs at Work Scale (BPNWS) in French, but items are also provided in English in the article. The BPNWS is a work-related self-report instrument designed to measure the degree to which the needs for autonomy, competence, and relatedness, as identified by Self-Determination Theory (Deci & Ryan, 2000), are satisfied at work. Using exploratory and confirmatory factor analysis, the first study examines the structure of the BPNWS in a group of 271 workers. The second study tests the measurement invariance of the scale in a group of 851 teachers from two different cultures, Canada and France. Results support the three-factor structure and show adequate internal consistency, as well as nomological validity across samples. © 2012 The Authors. Applied Psychology: Health and Well-Being © 2012 The International Association of Applied Psychology.

  10. Application of discriminant analysis-based model for prediction of risk of low back disorders due to workplace design in industrial jobs.

    PubMed

    Ganga, G M D; Esposto, K F; Braatz, D

    2012-01-01

    The occupational exposure limits of different risk factors for development of low back disorders (LBDs) have not yet been established. One of the main problems in setting such guidelines is the limited understanding of how different risk factors for LBDs interact in causing injury, since the nature and mechanism of these disorders are relatively unknown phenomena. Industrial ergonomists' role becomes further complicated because the potential risk factors that may contribute towards the onset of LBDs interact in a complex manner, which makes it difficult to discriminate in detail among the jobs that place workers at high or low risk of LBDs. The purpose of this paper was to develop a comparative study between predictions based on the neural network-based model proposed by Zurada, Karwowski & Marras (1997) and a linear discriminant analysis model, for making predictions about industrial jobs according to their potential risk of low back disorders due to workplace design. The results obtained through applying the discriminant analysis-based model proved that it is as effective as the neural network-based model. Moreover, the discriminant analysis-based model proved to be more advantageous regarding cost and time savings for future data gathering.

  11. [Balanced scorecard for performance measurement of a nursing organization in a Korean hospital].

    PubMed

    Hong, Yoonmi; Hwang, Kyung Ja; Kim, Mi Ja; Park, Chang Gi

    2008-02-01

    The purpose of this study was to develop a balanced scorecard (BSC) for performance measurement of a Korean hospital nursing organization and to evaluate the validity and reliability of performance measurement indicators. Two hundred fifty-nine nurses in a Korean hospital participated in a survey questionnaire that included 29-item performance evaluation indicators developed by investigators of this study based on the Kaplan and Norton's BSC (1992). Cronbach's alpha was used to test the reliability of the BSC. Exploratory and confirmatory factor analysis with a structure equation model (SEM) was applied to assess the construct validity of the BSC. Cronbach's alpha of 29 items was .948. Factor analysis of the BSC showed 5 principal components (eigen value >1.0) which explained 62.7% of the total variance, and it included a new one, community service. The SEM analysis results showed that 5 components were significant for the hospital BSC tool. High degree of reliability and validity of this BSC suggests that it may be used for performance measurements of a Korean hospital nursing organization. Future studies may consider including a balanced number of nurse managers and staff nurses in the study. Further data analysis on the relationships among factors is recommended.

  12. Water quality analysis of the Rapur area, Andhra Pradesh, South India using multivariate techniques

    NASA Astrophysics Data System (ADS)

    Nagaraju, A.; Sreedhar, Y.; Thejaswi, A.; Sayadi, Mohammad Hossein

    2017-10-01

    The groundwater samples from Rapur area were collected from different sites to evaluate the major ion chemistry. The large number of data can lead to difficulties in the integration, interpretation, and representation of the results. Two multivariate statistical methods, hierarchical cluster analysis (HCA) and factor analysis (FA), were applied to evaluate their usefulness to classify and identify geochemical processes controlling groundwater geochemistry. Four statistically significant clusters were obtained from 30 sampling stations. This has resulted two important clusters viz., cluster 1 (pH, Si, CO3, Mg, SO4, Ca, K, HCO3, alkalinity, Na, Na + K, Cl, and hardness) and cluster 2 (EC and TDS) which are released to the study area from different sources. The application of different multivariate statistical techniques, such as principal component analysis (PCA), assists in the interpretation of complex data matrices for a better understanding of water quality of a study area. From PCA, it is clear that the first factor (factor 1), accounted for 36.2% of the total variance, was high positive loading in EC, Mg, Cl, TDS, and hardness. Based on the PCA scores, four significant cluster groups of sampling locations were detected on the basis of similarity of their water quality.

  13. The Bicycle Drawing Test: What Does It Measure in Developmentally Typical Children?

    PubMed

    Cannoni, Eleonora; Di Norcia, Anna; Bombi, Anna Silvia; Di Giunta, Laura

    2015-10-01

    To verify the dimensionality of Bicycle Drawing Test (BDT), we applied the coding system of Greenberg, Rodriguez, and Sesta to bicycle drawings made by 295 boys and 320 girls (6-10 years old) with typical development, and submitted the data to item analysis, exploratory factor analysis, and confirmatory factor analysis. These analyses confirmed only two of the original four dimensions of the BDT: spatial reasoning and visual-motor control. The scores in these two factors were correlated with the Colored Progressive Matrices, the Rey Complex Figure (Copy and Memory) and with the teachers' ratings in mathematics, language, and drawing. The correlations, albeit moderate in magnitude, were consistent with the hypothesized convergent and discriminant validity. After checking for measurement invariance across gender and age, we conducted two analyses of variance, the first of which showed a significant difference between younger children (6-8 years old) and older children (9-10 years old); the analysis of variance by gender did not yield significant differences. These data enhance the usefulness of the BDT as a measure of separate cognitive components, but do not support its use as a measure of mechanical reasoning. © The Author(s) 2014.

  14. Individual and Interactive Effects of Socio-Ecological Factors on Dengue Fever at Fine Spatial Scale: A Geographical Detector-Based Analysis

    PubMed Central

    Li, Xing; Wang, Jin; Lin, Hualiang; Chen, Lingling; Wu, Zhifeng; Ma, Wenjun

    2017-01-01

    Background: Large spatial heterogeneity was observed in the dengue fever outbreak in Guangzhou in 2014, however, the underlying reasons remain unknown. We examined whether socio-ecological factors affected the spatial distribution and their interactive effects. Methods: Moran’s I was applied to first examine the spatial cluster of dengue fever in Guangzhou. Nine socio-ecological factors were chosen to represent the urbanization level, economy, accessibility, environment, and the weather of the 167 townships/streets in Guangzhou, and then the geographical detector was applied to analyze the individual and interactive effects of these factors on the dengue outbreak. Results: Four clusters of dengue fever were identified in Guangzhou in 2014, including one hot spot in the central area of Guangzhou and three cold spots in the suburban districts. For individual effects, the temperature (q = 0.33) was the dominant factor of dengue fever, followed by precipitation (q = 0.24), road density (q = 0.24), and water body area (q = 0.23). For the interactive effects, the combination of high precipitation, high temperature, and high road density might result in increased dengue fever incidence. Moreover, urban villages might be the dengue fever hot spots. Conclusions: Our study suggests that some socio-ecological factors might either separately or jointly influence the spatial distribution of dengue fever in Guangzhou. PMID:28714925

  15. Are only Emotional Strengths Emotional? Character Strengths and Disposition to Positive Emotions.

    PubMed

    Güsewell, Angelika; Ruch, Willibald

    2012-07-01

    This study aimed to examine the relations between character strengths and dispositional positive emotions (i.e. joy, contentment, pride, love, compassion, amusement, and awe). A sample of 574 German-speaking adults filled in the Dispositional Positive Emotion Scales (DPES; Shiota, Keltner, & John, 2006), and the Values in Action Inventory of Strengths (VIA-IS; Peterson, Park, & Seligman, 2005). The factorial structure of the DPES was examined on item level. Joy and contentment could not be clearly separated; the items of the other five emotions loaded on separate factors. A confirmatory factor analysis assuming two latent factors (self-oriented and object/situation specific) was computed on scale level. Results confirmed the existence of these factors, but also indicated that the seven emotions did not split up into two clearly separable families. Correlations between dispositional positive emotions and character strengths were positive and generally low to moderate; a few theoretically meaningful strengths-emotions pairs yielded coefficients>.40. Finally, the link between five character strengths factors (i.e. emotional strengths, interpersonal strengths, strengths of restraint, intellectual strengths, and theological strengths) and the emotional dispositions was examined. Each of the factors displayed a distinctive "emotional pattern"; emotional strengths evidenced the most numerous and strongest links to emotional dispositions. © 2012 The Authors. Applied Psychology: Health and Well-Being © 2012 The International Association of Applied Psychology.

  16. Individual and Interactive Effects of Socio-Ecological Factors on Dengue Fever at Fine Spatial Scale: A Geographical Detector-Based Analysis.

    PubMed

    Cao, Zheng; Liu, Tao; Li, Xing; Wang, Jin; Lin, Hualiang; Chen, Lingling; Wu, Zhifeng; Ma, Wenjun

    2017-07-17

    Background : Large spatial heterogeneity was observed in the dengue fever outbreak in Guangzhou in 2014, however, the underlying reasons remain unknown. We examined whether socio-ecological factors affected the spatial distribution and their interactive effects. Methods : Moran's I was applied to first examine the spatial cluster of dengue fever in Guangzhou. Nine socio-ecological factors were chosen to represent the urbanization level, economy, accessibility, environment, and the weather of the 167 townships/streets in Guangzhou, and then the geographical detector was applied to analyze the individual and interactive effects of these factors on the dengue outbreak. Results : Four clusters of dengue fever were identified in Guangzhou in 2014, including one hot spot in the central area of Guangzhou and three cold spots in the suburban districts. For individual effects, the temperature ( q = 0.33) was the dominant factor of dengue fever, followed by precipitation ( q = 0.24), road density ( q = 0.24), and water body area ( q = 0.23). For the interactive effects, the combination of high precipitation, high temperature, and high road density might result in increased dengue fever incidence. Moreover, urban villages might be the dengue fever hot spots. Conclusions : Our study suggests that some socio-ecological factors might either separately or jointly influence the spatial distribution of dengue fever in Guangzhou.

  17. High Prevalence of Vitamin D Deficiency among Iranian Population: A Systematic Review and Meta-Analysis

    PubMed Central

    Tabrizi, Reza; Moosazadeh, Mahmood; Akbari, Maryam; Dabbaghmanesh, Mohammad Hossein; Mohamadkhani, Minoo; Asemi, Zatollah; Heydari, Seyed Taghi; Akbari, Mojtaba; Lankarani, Kamran B

    2018-01-01

    Background The prevention and correction of vitamin D deficiency requires a precise depiction of the current situation and identification of risk factors in each region. The present study attempted to determine these entities using a systematic review and meta-analysis in Iran. Methods Articles published online in Persian and English between 2000 and November 1, 2016, were reviewed. This was carried out using national databases such as SID, IranMedex, Magiran, and IranDoc and international databases such as PubMed, Google Scholar, and Scopus. The heterogeneity index among the studies was determined using the Cochran (Q) and I2 test. Based on the heterogeneity results, the random-effect model was applied to estimate the prevalence of vitamin D deficiency. In addition, meta-regression analysis was used to determine heterogeneity-suspected factors, and the Egger test was applied to identify publication bias. Results The meta-analysis of 48 studies identified 18531 individuals with vitamin D deficiency. According to the random-effect model, the prevalence of vitamin D deficiency among male, female, and pregnant women was estimated to be 45.64% (95% CI: 29.63 to 61.65), 61.90% (95% CI: 48.85 to 74.96), and 60.45% (95% CI: 23.73 to 97.16), respectively. The results of the meta-regression analysis indicated that the prevalence of vitamin D deficiency was significantly different in various geographical regions (β=4.4; P=0.023). Conclusion The results obtained showed a significant prevalence of vitamin D deficiency among the Iranian population, a condition to be addressed by appropriate planning. PMID:29749981

  18. Experimental variability and data pre-processing as factors affecting the discrimination power of some chemometric approaches (PCA, CA and a new algorithm based on linear regression) applied to (+/-)ESI/MS and RPLC/UV data: Application on green tea extracts.

    PubMed

    Iorgulescu, E; Voicu, V A; Sârbu, C; Tache, F; Albu, F; Medvedovici, A

    2016-08-01

    The influence of the experimental variability (instrumental repeatability, instrumental intermediate precision and sample preparation variability) and data pre-processing (normalization, peak alignment, background subtraction) on the discrimination power of multivariate data analysis methods (Principal Component Analysis -PCA- and Cluster Analysis -CA-) as well as a new algorithm based on linear regression was studied. Data used in the study were obtained through positive or negative ion monitoring electrospray mass spectrometry (+/-ESI/MS) and reversed phase liquid chromatography/UV spectrometric detection (RPLC/UV) applied to green tea extracts. Extractions in ethanol and heated water infusion were used as sample preparation procedures. The multivariate methods were directly applied to mass spectra and chromatograms, involving strictly a holistic comparison of shapes, without assignment of any structural identity to compounds. An alternative data interpretation based on linear regression analysis mutually applied to data series is also discussed. Slopes, intercepts and correlation coefficients produced by the linear regression analysis applied on pairs of very large experimental data series successfully retain information resulting from high frequency instrumental acquisition rates, obviously better defining the profiles being compared. Consequently, each type of sample or comparison between samples produces in the Cartesian space an ellipsoidal volume defined by the normal variation intervals of the slope, intercept and correlation coefficient. Distances between volumes graphically illustrates (dis)similarities between compared data. The instrumental intermediate precision had the major effect on the discrimination power of the multivariate data analysis methods. Mass spectra produced through ionization from liquid state in atmospheric pressure conditions of bulk complex mixtures resulting from extracted materials of natural origins provided an excellent data basis for multivariate analysis methods, equivalent to data resulting from chromatographic separations. The alternative evaluation of very large data series based on linear regression analysis produced information equivalent to results obtained through application of PCA an CA. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Analysis of risk factors for central venous port failure in cancer patients

    PubMed Central

    Hsieh, Ching-Chuan; Weng, Hsu-Huei; Huang, Wen-Shih; Wang, Wen-Ke; Kao, Chiung-Lun; Lu, Ming-Shian; Wang, Chia-Siu

    2009-01-01

    AIM: To analyze the risk factors for central port failure in cancer patients administered chemotherapy, using univariate and multivariate analyses. METHODS: A total of 1348 totally implantable venous access devices (TIVADs) were implanted into 1280 cancer patients in this cohort study. A Cox proportional hazard model was applied to analyze risk factors for failure of TIVADs. Log-rank test was used to compare actuarial survival rates. Infection, thrombosis, and surgical complication rates (χ2 test or Fisher’s exact test) were compared in relation to the risk factors. RESULTS: Increasing age, male gender and open-ended catheter use were significant risk factors reducing survival of TIVADs as determined by univariate and multivariate analyses. Hematogenous malignancy decreased the survival time of TIVADs; this reduction was not statistically significant by univariate analysis [hazard ratio (HR) = 1.336, 95% CI: 0.966-1.849, P = 0.080)]. However, it became a significant risk factor by multivariate analysis (HR = 1.499, 95% CI: 1.079-2.083, P = 0.016) when correlated with variables of age, sex and catheter type. Close-ended (Groshong) catheters had a lower thrombosis rate than open-ended catheters (2.5% vs 5%, P = 0.015). Hematogenous malignancy had higher infection rates than solid malignancy (10.5% vs 2.5%, P < 0.001). CONCLUSION: Increasing age, male gender, open-ended catheters and hematogenous malignancy were risk factors for TIVAD failure. Close-ended catheters had lower thrombosis rates and hematogenous malignancy had higher infection rates. PMID:19787834

  20. Validation of the Center for Epidemiological Studies Depression Scale among Korean Adolescents.

    PubMed

    Heo, Eun-Hye; Choi, Kyeong-Sook; Yu, Je-Chun; Nam, Ji-Ae

    2018-02-01

    The Center for Epidemiological Studies Depression Scale (CES-D) is designed to measure the current level of depressive symptomatology in the general population. However, no review has examined whether the scale is reliable and valid among children and adolescents in Korea. The purpose of this study was to test whether the Korean form of the CES-D is valid in adolescents. Data were obtained from 1,884 adolescents attending grades 1-3 in Korean middle schools. Reliability was evaluated by internal consistency (Cronbach's alpha). Concurrent validity was evaluated by a correlation analysis between the CES-D and other scales. Construct validity was evaluated by exploratory factor and confirmatory factor analyses. The internal consistency coefficient for the entire group was 0.88. The CES-D was positively correlated with scales that measure negative psychological constructs, such as the State Anxiety Inventory for Children, the Korean Social Anxiety Scale for Children and Adolescents, and the Reynold Suicidal Ideation Questionnaire, but it was negatively correlated with scales that measure positive psychological constructs, such as the Korean version of the Rosenberg Self-Esteem Scale and the Connor-Davidson Resilience Scale-2. The CES-D was examined by three-dimensional exploratory factor analysis, and the three-factor structure of the scale explained 53.165% of the total variance. The variance explained by factor I was 24.836%, that explained by factor II was 15.988%, and that explained by factor III was 12.341%. The construct validity of the CES-D was tested by confirmatory factor analysis, and we applied the entire group's data using a three-factor hierarchical model. The fit index showed a level similar to those of other countries' adolescent samples. The CES-D has high internal consistency and addresses psychological constructs similar to those addressed by other scales. The CES-D showed a three-factor structure in an exploratory factor analysis. The present findings suggest that the CES-D is a useful and reliable tool for measuring depression in Korean adolescents.

  1. Developing an instrument to measure effective factors on Clinical Learning.

    PubMed

    Dadgaran, Ideh; Shirazi, Mandana; Mohammadi, Aeen; Ravari, Ali

    2016-07-01

    Although nursing students spend a large part of their learning period in the clinical environment, clinical learning has not been perceived by its nature yet. To develop an instrument to measure effective factors on clinical learning in nursing students. This is a mixed methods study performed in 2 steps. First, the researchers defined "clinical learning" in nursing students through qualitative content analysis and designed items of the questionnaire based on semi-structured individual interviews with nursing students. Then, as the second step, psychometric properties of the questionnaire were evaluated using the face validity, content validity, construct validity, and internal consistency evaluated on 227 students from fourth or higher semesters. All the interviews were recorded and transcribed, and then, they were analyzed using Max Qualitative Data Analysis and all of qualitative data were analyzed using SPSS 14. To do the study, we constructed the preliminary questionnaire containing 102 expressions. After determination of face and content validities by qualitative and quantitative approaches, the expressions of the questionnaire were reduced to 45. To determine the construct validity, exploratory factor analysis was applied. The results indicated that the maximum variance percentage (40.55%) was defined by the first 3 factors while the rest of the total variance percentage (59.45%) was determined by the other 42 factors. Results of exploratory factor analysis of this questionnaire indicated the presence of 3 instructor-staff, students, and educational related factors. Finally, 41 expressions were kept in 3 factor groups. The α-Cronbach coefficient (0.93) confirmed the high internal consistency of the questionnaire. Results indicated that the prepared questionnaire was an efficient instrument in the study of the effective factors on clinical learning as viewed by nursing students since it involves 41 expressions and properties such as instrument design based on perception and experiences of the nursing students about effective factors on clinical learning, definition of facilitator and preventive factors of the clinical learning, simple scoring, suitable validity and reliability, and applicability in different occasions.

  2. Categorization of the trophic status of a hydroelectric power plant reservoir in the Brazilian Amazon by statistical analyses and fuzzy approaches.

    PubMed

    da Costa Lobato, Tarcísio; Hauser-Davis, Rachel Ann; de Oliveira, Terezinha Ferreira; Maciel, Marinalva Cardoso; Tavares, Maria Regina Madruga; da Silveira, Antônio Morais; Saraiva, Augusto Cesar Fonseca

    2015-02-15

    The Amazon area has been increasingly suffering from anthropogenic impacts, especially due to the construction of hydroelectric power plant reservoirs. The analysis and categorization of the trophic status of these reservoirs are of interest to indicate man-made changes in the environment. In this context, the present study aimed to categorize the trophic status of a hydroelectric power plant reservoir located in the Brazilian Amazon by constructing a novel Water Quality Index (WQI) and Trophic State Index (TSI) for the reservoir using major ion concentrations and physico-chemical water parameters determined in the area and taking into account the sampling locations and the local hydrological regimes. After applying statistical analyses (factor analysis and cluster analysis) and establishing a rule base of a fuzzy system to these indicators, the results obtained by the proposed method were then compared to the generally applied Carlson and a modified Lamparelli trophic state index (TSI), specific for trophic regions. The categorization of the trophic status by the proposed fuzzy method was shown to be more reliable, since it takes into account the specificities of the study area, while the Carlson and Lamparelli TSI do not, and, thus, tend to over or underestimate the trophic status of these ecosystems. The statistical techniques proposed and applied in the present study, are, therefore, relevant in cases of environmental management and policy decision-making processes, aiding in the identification of the ecological status of water bodies. With this, it is possible to identify which factors should be further investigated and/or adjusted in order to attempt the recovery of degraded water bodies. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Principal component analysis of the Norwegian version of the quality of life in late-stage dementia scale.

    PubMed

    Mjørud, Marit; Kirkevold, Marit; Røsvik, Janne; Engedal, Knut

    2014-01-01

    To investigate which factors the Quality of Life in Late-Stage Dementia (QUALID) scale holds when used among people with dementia (pwd) in nursing homes and to find out how the symptom load varies across the different severity levels of dementia. We included 661 pwd [mean age ± SD, 85.3 ± 8.6 years; 71.4% women]. The QUALID and the Clinical Dementia Rating (CDR) scale were applied. A principal component analysis (PCA) with varimax rotation and Kaiser normalization was applied to test the factor structure. Nonparametric analyses were applied to examine differences of symptom load across the three CDR groups. The mean QUALID score was 21.5 (±7.1), and the CDR scores of the three groups were 1 in 22.5%, 2 in 33.6% and 3 in 43.9%. The results of the statistical measures employed were the following: Crohnbach's α of QUALID, 0.74; Bartlett's test of sphericity, p <0.001; the Kaiser-Meyer-Olkin measure, 0.77. The PCA analysis resulted in three components accounting for 53% of the variance. The first component was 'tension' ('facial expression of discomfort', 'appears physically uncomfortable', 'verbalization suggests discomfort', 'being irritable and aggressive', 'appears calm', Crohnbach's α = 0.69), the second was 'well-being' ('smiles', 'enjoys eating', 'enjoys touching/being touched', 'enjoys social interaction', Crohnbach's α = 0.62) and the third was 'sadness' ('appears sad', 'cries', 'facial expression of discomfort', Crohnbach's α 0.65). The mean score on the components 'tension' and 'well-being' increased significantly with increasing severity levels of dementia. Three components of quality of life (qol) were identified. Qol decreased with increasing severity of dementia. © 2013 S. Karger AG, Basel.

  4. Fractography: determining the sites of fracture initiation.

    PubMed

    Mecholsky, J J

    1995-03-01

    Fractography is the analysis of fracture surfaces. Here, it refers to quantitative fracture surface analysis (FSA) in the context of applying the principles of fracture mechanics to the topography observed on the fracture surface of brittle materials. The application of FSA is based on the principle that encoded on the fracture surface of brittle materials is the entire history of the fracture process. It is our task to develop the skills and knowledge to decode this information. There are several motivating factors for applying our knowledge of FSA. The first and foremost is that there is specific, quantitative information to be obtained from the fracture surface. This information includes the identification of the size and location of the fracture initiating crack or defect, the stress state at failure, the existence, or not, of local or global residual stress, the existence, or not, of stress corrosion and a knowledge of local processing anomalies which affect the fracture process. The second motivating factor is that the information is free. Once a material is tested to failure, the encoded information becomes available. If we decide to observe the features produced during fracture then we are rewarded with much information. If we decide to ignore the fracture surface, then we are left to guess and/or reason as to the cause of the failure without the benefit of all of the possible information available. This paper addresses the application of quantitative fracture surface analysis to basic research, material and product development, and "trouble-shooting" of in-service failures. First, the basic principles involved will be presented. Next, the methodology necessary to apply the principles will be presented. Finally, a summary of the presentation will be made showing the applicability to design and reliability.

  5. ASPASIA: A toolkit for evaluating the effects of biological interventions on SBML model behaviour.

    PubMed

    Evans, Stephanie; Alden, Kieran; Cucurull-Sanchez, Lourdes; Larminie, Christopher; Coles, Mark C; Kullberg, Marika C; Timmis, Jon

    2017-02-01

    A calibrated computational model reflects behaviours that are expected or observed in a complex system, providing a baseline upon which sensitivity analysis techniques can be used to analyse pathways that may impact model responses. However, calibration of a model where a behaviour depends on an intervention introduced after a defined time point is difficult, as model responses may be dependent on the conditions at the time the intervention is applied. We present ASPASIA (Automated Simulation Parameter Alteration and SensItivity Analysis), a cross-platform, open-source Java toolkit that addresses a key deficiency in software tools for understanding the impact an intervention has on system behaviour for models specified in Systems Biology Markup Language (SBML). ASPASIA can generate and modify models using SBML solver output as an initial parameter set, allowing interventions to be applied once a steady state has been reached. Additionally, multiple SBML models can be generated where a subset of parameter values are perturbed using local and global sensitivity analysis techniques, revealing the model's sensitivity to the intervention. To illustrate the capabilities of ASPASIA, we demonstrate how this tool has generated novel hypotheses regarding the mechanisms by which Th17-cell plasticity may be controlled in vivo. By using ASPASIA in conjunction with an SBML model of Th17-cell polarisation, we predict that promotion of the Th1-associated transcription factor T-bet, rather than inhibition of the Th17-associated transcription factor RORγt, is sufficient to drive switching of Th17 cells towards an IFN-γ-producing phenotype. Our approach can be applied to all SBML-encoded models to predict the effect that intervention strategies have on system behaviour. ASPASIA, released under the Artistic License (2.0), can be downloaded from http://www.york.ac.uk/ycil/software.

  6. Assessment of relevant factors and relationships concerning human dermal exposure to pesticides in greenhouse applications.

    PubMed

    Martínez Vidal, Jose L; Egea González, Francisco J; Garrido Frenich, Antonia; Martínez Galera, María; Aguilera, Pedro A; López Carrique, Enrique

    2002-08-01

    Principal component analysis (PCA) was applied to the gas chromatographic data obtained from 23 different greenhouse trials. This was used to establish which factors, including application technique (very small, small, medium and large drop-size), crop characteristics (short/tall, thin/dense) and pattern application of the operator (walking towards or away from the treated area) are relevant to the dermal exposure levels of greenhouse applicators. The results showed that the highest exposure by pesticides during field applications in greenhouses, in the climatic conditions and in the crop conditions typical of a southern European country, occurs on the lower legs and front thighs of the applicators. Similar results were obtained by hierarchical cluster analysis (HCA). Drop-size seems to be very important in determining total exposure, while height and density of crops have little influence on total exposure under the conditions of the present study. No pesticide type is a major factor in total exposure. The application of multiple regression analysis (MRA) allowed assessment of the relationships between the pesticide exposure of the less affected parts of the body with the most affected parts.

  7. An Efficient Taguchi Approach for the Performance Optimization of Health, Safety, Environment and Ergonomics in Generation Companies

    PubMed Central

    Azadeh, Ali; Sheikhalishahi, Mohammad

    2014-01-01

    Background A unique framework for performance optimization of generation companies (GENCOs) based on health, safety, environment, and ergonomics (HSEE) indicators is presented. Methods To rank this sector of industry, the combination of data envelopment analysis (DEA), principal component analysis (PCA), and Taguchi are used for all branches of GENCOs. These methods are applied in an integrated manner to measure the performance of GENCO. The preferred model between DEA, PCA, and Taguchi is selected based on sensitivity analysis and maximum correlation between rankings. To achieve the stated objectives, noise is introduced into input data. Results The results show that Taguchi outperforms other methods. Moreover, a comprehensive experiment is carried out to identify the most influential factor for ranking GENCOs. Conclusion The approach developed in this study could be used for continuous assessment and improvement of GENCO's performance in supplying energy with respect to HSEE factors. The results of such studies would help managers to have better understanding of weak and strong points in terms of HSEE factors. PMID:26106505

  8. Quantification method analysis of the relationship between occupant injury and environmental factors in traffic accidents.

    PubMed

    Ju, Yong Han; Sohn, So Young

    2011-01-01

    Injury analysis following a vehicle crash is one of the most important research areas. However, most injury analyses have focused on one-dimensional injury variables, such as the AIS (Abbreviated Injury Scale) or the IIS (Injury Impairment Scale), at a time in relation to various traffic accident factors. However, these studies cannot reflect the various injury phenomena that appear simultaneously. In this paper, we apply quantification method II to the NASS (National Automotive Sampling System) CDS (Crashworthiness Data System) to find the relationship between the categorical injury phenomena, such as the injury scale, injury position, and injury type, and the various traffic accident condition factors, such as speed, collision direction, vehicle type, and seat position. Our empirical analysis indicated the importance of safety devices, such as restraint equipment and airbags. In addition, we found that narrow impact, ejection, air bag deployment, and higher speed are associated with more severe than minor injury to the thigh, ankle, and leg in terms of dislocation, abrasion, or laceration. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. [Analysis of citations and national and international impact factor of Farmacia Hospitalaria (2001-2005)].

    PubMed

    Aleixandre-Benavent, R; González Alcaide, G; Miguel-Dasit, A; González de Dios, J; de Granda Orive, J I; Valderrama Zurián, J C

    2007-01-01

    The objective of this study is to analyse the citation patterns and impact and immediacy indicators of the Farmacia Hospitalaria journal during the period 2001-2005. An analysis of citations chosen from 101 Spanish health science journals was carried out in order to determine the citing and cited journals and the national and international impact and immediacy indicators. A similar methodology used by Thomson ISI in Science Citation Index (SCI) and Journal Citation Reports (JRC) was applied. Farmacia Hospitalaria made 1,370 citations to 316 different journals. The percentage of self-citations was 9%. The national impact factor increased from 0.178 points in 2001 to 0.663 points in 2005 while the international impact factor increased from 0.178 to 0.806 for the same period. The analysis of citation patterns demonstrates the multidisciplinary nature of Farmacia Hospitalaria and a significant growth in the impact indicators over recent years. These indicators are higher than those of some other pharmacy journals included in Journal Citation Reports. Self-citation was not excessive and was similar to that of other journals.

  10. Improvement of Quench Factor Analysis in Phase and Hardness Prediction of a Quenched Steel

    NASA Astrophysics Data System (ADS)

    Kianezhad, M.; Sajjadi, S. A.

    2013-05-01

    The accurate prediction of alloys' properties introduced by heat treatment has been considered by many researchers. The advantages of such predictions are reduction of test trails and materials' consumption as well as time and energy saving. One of the most important methods to predict hardness in quenched steel parts is Quench Factor Analysis (QFA). Classical QFA is based on the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation. In this study, a modified form of the QFA based on the work by Rometsch et al. is compared with the classical QFA, and they are applied to prediction of hardness of steels. For this purpose, samples of CK60 steel were utilized as raw material. They were austenitized at 1103 K (830 °C). After quenching in different environments, they were cut and their hardness was determined. In addition, the hardness values of the samples were fitted using the classical and modified equations for the quench factor analysis and the results were compared. Results showed a significant improvement in fitted values of the hardness and proved the higher efficiency of the new method.

  11. Child and Family Factors Associated with the Use of Services for Preschoolers with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Irvin, Dwight W.; McBee, Matthew; Boyd, Brian A.; Hume, Kara; Odom, Samuel L.

    2012-01-01

    This study examines child and family characteristics thought to affect the dosage and type of common in-school and private services (i.e., speech language therapy (SLT), occupational therapy (OT) and applied behavior analysis (ABA)) received by children with ASD. Participants included 137 families and their preschool-aged children with ASD from…

  12. The Influence of Organizational Image on College Selection: What Students Seek in Institutions of Higher Education

    ERIC Educational Resources Information Center

    Pampaloni, Andrea M.

    2010-01-01

    Colleges and universities rely on their image to attract new members. This study focuses on the decision-making process of students preparing to apply to college. High school students were surveyed at college open houses to identify the factors most influential to their college application decision-making. A multi-methods analysis found that…

  13. Confirmatory Factor Analysis of the Test of Gross Motor Development-2

    ERIC Educational Resources Information Center

    Wong, Ka Yee Allison; Cheung, Siu Yin

    2010-01-01

    The purpose of this study was to examine the underlying structure of the second edition of the Test of Gross Motor Development-2 (Ulrich, 2000) as applied to Chinese children. The Test of Gross Motor Development-2 was administered to 626 Hong Kong Chinese children. The outlier test with standard scoring was utilized. After data screening, a total…

  14. How Can We Stop Our Children from Hurting Themselves? Stages of Change, Motivational Interviewing, and Exposure Therapy Applications for Non-Suicidal Self-Injury in Children and Adolescents

    ERIC Educational Resources Information Center

    Kamen, David G.

    2009-01-01

    Non-suicidal self-injury (NSSI) in children and adolescents is a major public health problem. Fortunately, we can apply functional analysis, in conjunction with empirically validated NSSI assessment measurements, to precisely evaluate the biopsychosocial risk factors and reinforcements that contextualize NSSI. Empirically validated behavioral…

  15. The Impact of Letter Grades on Student Effort, Course Selection, and Major Choice: A Regression-Discontinuity Analysis

    ERIC Educational Resources Information Center

    Main, Joyce B.; Ost, Ben

    2014-01-01

    The authors apply a regression-discontinuity design to identify the causal impact of letter grades on student effort within a course, subsequent credit hours taken, and the probability of majoring in economics. Their methodology addresses key issues in identifying the causal impact of letter grades: correlation with unobservable factors, such as…

  16. Measuring Preschool Children Temperament: Implications for Preschool Care and Education Practice

    ERIC Educational Resources Information Center

    Vorkapic, Sanja Tatalovic; Loncaric, Darko

    2015-01-01

    With the aim of measuring preschool children temperament, EASI temperament Survey has been applied. Preschool teachers (N = 192), all female, rated a total of N = 3275 children (1612 girls and 1639 boys) with mean age M 4.368 (SD = 1.482) within age range between 7 months and 7.7 years. Validation for the instrument was run. Factor analysis on…

  17. An Integrated Systems Genetics and Omics Toolkit to Probe Gene Function.

    PubMed

    Li, Hao; Wang, Xu; Rukina, Daria; Huang, Qingyao; Lin, Tao; Sorrentino, Vincenzo; Zhang, Hongbo; Bou Sleiman, Maroun; Arends, Danny; McDaid, Aaron; Luan, Peiling; Ziari, Naveed; Velázquez-Villegas, Laura A; Gariani, Karim; Kutalik, Zoltan; Schoonjans, Kristina; Radcliffe, Richard A; Prins, Pjotr; Morgenthaler, Stephan; Williams, Robert W; Auwerx, Johan

    2018-01-24

    Identifying genetic and environmental factors that impact complex traits and common diseases is a high biomedical priority. Here, we developed, validated, and implemented a series of multi-layered systems approaches, including (expression-based) phenome-wide association, transcriptome-/proteome-wide association, and (reverse-) mediation analysis, in an open-access web server (systems-genetics.org) to expedite the systems dissection of gene function. We applied these approaches to multi-omics datasets from the BXD mouse genetic reference population, and identified and validated associations between genes and clinical and molecular phenotypes, including previously unreported links between Rpl26 and body weight, and Cpt1a and lipid metabolism. Furthermore, through mediation and reverse-mediation analysis we established regulatory relations between genes, such as the co-regulation of BCKDHA and BCKDHB protein levels, and identified targets of transcription factors E2F6, ZFP277, and ZKSCAN1. Our multifaceted toolkit enabled the identification of gene-gene and gene-phenotype links that are robust and that translate well across populations and species, and can be universally applied to any populations with multi-omics datasets. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Urbanization and human health in urban India: institutional analysis of water-borne diseases in Ahmedabad.

    PubMed

    Saravanan, V S; Ayessa Idenal, Marissa; Saiyed, Shahin; Saxena, Deepak; Gerke, Solvay

    2016-10-01

    Diseases are rapidly urbanizing. Ageing infrastructures, high levels of inequality, poor urban governance, rapidly growing economies and highly dense and mobile populations all create environments rife for water-borne diseases. This article analyzes the role of institutions as crosscutting entities among a myriad of factors that breed water-borne diseases in the city of Ahmedabad, India. It applies 'path dependency' and a 'rational choice' perspective to understand the factors facilitating the breeding of diseases. This study is based on household surveys of approximately 327 households in two case study wards and intermittent interviews with key informants over a period of 2 years. Principle component analysis is applied to reduce the data and convert a set of observations, which potentially correlate with each other, into components. Institutional analyses behind these components reveal the role of social actors in exploiting the deeply rooted inefficiencies affecting urban health. This has led to a vicious cycle; breaking this cycle requires understanding the political dynamics that underlie the exposure and prevalence of diseases to improve urban health. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Simple construct evaluation with latent class analysis: An investigation of Facebook addiction and the development of a short form of the Facebook Addiction Test (F-AT).

    PubMed

    Dantlgraber, Michael; Wetzel, Eunike; Schützenberger, Petra; Stieger, Stefan; Reips, Ulf-Dietrich

    2016-09-01

    In psychological research, there is a growing interest in using latent class analysis (LCA) for the investigation of quantitative constructs. The aim of this study is to illustrate how LCA can be applied to gain insights on a construct and to select items during test development. We show the added benefits of LCA beyond factor-analytic methods, namely being able (1) to describe groups of participants that differ in their response patterns, (2) to determine appropriate cutoff values, (3) to evaluate items, and (4) to evaluate the relative importance of correlated factors. As an example, we investigated the construct of Facebook addiction using the Facebook Addiction Test (F-AT), an adapted version of the Internet Addiction Test (I-AT). Applying LCA facilitates the development of new tests and short forms of established tests. We present a short form of the F-AT based on the LCA results and validate the LCA approach and the short F-AT with several external criteria, such as chatting, reading newsfeeds, and posting status updates. Finally, we discuss the benefits of LCA for evaluating quantitative constructs in psychological research.

  20. Quantitative Analysis of the Efficiency of OLEDs.

    PubMed

    Sim, Bomi; Moon, Chang-Ki; Kim, Kwon-Hyeon; Kim, Jang-Joo

    2016-12-07

    We present a comprehensive model for the quantitative analysis of factors influencing the efficiency of organic light-emitting diodes (OLEDs) as a function of the current density. The model takes into account the contribution made by the charge carrier imbalance, quenching processes, and optical design loss of the device arising from various optical effects including the cavity structure, location and profile of the excitons, effective radiative quantum efficiency, and out-coupling efficiency. Quantitative analysis of the efficiency can be performed with an optical simulation using material parameters and experimental measurements of the exciton profile in the emission layer and the lifetime of the exciton as a function of the current density. This method was applied to three phosphorescent OLEDs based on a single host, mixed host, and exciplex-forming cohost. The three factors (charge carrier imbalance, quenching processes, and optical design loss) were influential in different ways, depending on the device. The proposed model can potentially be used to optimize OLED configurations on the basis of an analysis of the underlying physical processes.

Top