Sample records for modeling analyses examined

  1. Analysing Possible Applications for Available Mathematical Models of Tracked Vehicle Movement Over the Rough Terrain to Examine Tracked Chain Dynamic Processes

    Directory of Open Access Journals (Sweden)

    M. E. Lupyan


    Full Text Available The article offered for consideration provides a survey of methods to study a tracked vehicle movement over unpaved grounds and obstacles using various software systems. The relevant issue is to optimize chassis elements of a caterpillar at the design stage. The challenges, engineers face using different methods to study the tracked vehicle elements, are given. Advantages of using simulation to study a state of the various components of the loaded chassis are described. Beside, an important and relevant issue is brought up i.e. modeling a vehicle movement in real time.While writing an article, different modeling methods for an interaction between a tracked vehicle chassis and an underlying subgrade used both in domestic and in foreign practice have been analysed. The applied analytical assumptions in creating these models and their basic elements are described. The way to specify an interaction between the track and road wheels of a caterpillar, crawler belt specification, and interaction between its elements have been analysed in detail as well. Special attention was also paid to the various ways of specifying the subgrade both in planar models and in models enabling us to study all chassis elements of a caterpillar as a whole.In addition to the classical simulation of tracked vehicle movement used to analyse Ride qualities of tracked vehicle and loaded state of various chassis elements, is offered a model used to simulate a movement coil in real time.The article presents advantages and disadvantages of different models of movement in terms of engineering analysis of caterpillar elements. A task to develop a simulation model of caterpillar movement is set. Requirements for a model in case of its use in engineering analysis of chassis elements of a caterpillar are defined. A problem of a lack of the single technique to conduct engineering analysis of tracked vehicle chassis is noted. 

  2. An extensible analysable system model

    DEFF Research Database (Denmark)

    Probst, Christian W.; Hansen, Rene Rydhof


    Analysing real-world systems for vulnerabilities with respect to security and safety threats is a difficult undertaking, not least due to a lack of availability of formalisations for those systems. While both formalisations and analyses can be found for artificial systems such as software......, this does not hold for real physical systems. Approaches such as threat modelling try to target the formalisation of the real-world domain, but still are far from the rigid techniques available in security research. Many currently available approaches to assurance of critical infrastructure security...... are based on (quite successful) ad-hoc techniques. We believe they can be significantly improved beyond the state-of-the-art by pairing them with static analyses techniques. In this paper we present an approach to both formalising those real-world systems, as well as providing an underlying semantics, which...

  3. Destructive examination and analyses of pulled steam generator tubes

    International Nuclear Information System (INIS)

    Kim, Dong Jin; Kim, H. P.; Kim, J. S.; Lim, Y. S.; Hwang, S. S.; Kim, S. W.; Jeong, M. K.; Hong, J. H.; Kim, W. W.


    Steam generator model F in Kori 3, Younggwang 2 and Younggwang 1 as 950MWe PWR was provided by Westinghouse. Steam generator tube made of Alloy 600TT material (outer diameter 0.688'(17.475 mm), thickness 0.04'(1.016mm) in Blairsville was provided by Huntington alloys. Steam generator in Ulchin 4 as 1000MWe KHNP PWR was manufactured by Doosan heavy industry and steam generator tubes were manufactured by B and W (Bobcock and Wilcox). Alloy 600 MA was used as steam generator tubing material of outer diameter 19.05mm and thickness 1.07mm. Five tubes of Alloy 600TT which showed crack signal from non-destructive examination were pulled from Kori 3, Younggwang 2 and Younggwang 1. Two tubes which showed crack signal from non-destructive examination were pulled from Ulchin 4. For the pulled tubes, KAERI performed destructive examination. Through the destructive examination, the existence of cracks were confirmed and the cause of crack was investigated. Remedy was also suggested to mitigate the present circumstances. Stress corrosion cracking (SCC) was observed for Alloy 600TT tubes. It was recommended that the sludge content should be lowered, deleterious elements and MRI should be maintained continuously. For Ulchin 4, SCC was confirmed for Alloy 600MA tubes. It is necessary to lower and remove the sludge in the near term. In the longer term, replacement of steam generator was suggested

  4. Graphical models for genetic analyses

    DEFF Research Database (Denmark)

    Lauritzen, Steffen Lilholt; Sheehan, Nuala A.


    This paper introduces graphical models as a natural environment in which to formulate and solve problems in genetics and related areas. Particular emphasis is given to the relationships among various local computation algorithms which have been developed within the hitherto mostly separate areas...... of graphical models and genetics. The potential of graphical models is explored and illustrated through a number of example applications where the genetic element is substantial or dominating....

  5. Nutrients from dairy foods are difficult to replace in diets of Americans: food pattern modeling and an analyses of the National Health and Nutrition Examination Survey 2003-2006. (United States)

    Fulgoni, Victor L; Keast, Debra R; Auestad, Nancy; Quann, Erin E


    Because dairy products provide shortfall nutrients (eg, calcium, potassium, and vitamin D) and other important nutrients, this study hypothesized that it would be difficult for Americans to meet nutritional requirements for these nutrients in the absence of dairy product consumption or when recommended nondairy calcium sources are consumed. To test this hypothesis, MyPyramid dietary pattern modeling exercises and an analyses of data from the National Health and Nutrition Examination Survey 2003-2006 were conducted in those aged at least 2 years (n = 16 822). Impact of adding or removing 1 serving of dairy, removing all dairy, and replacing dairy with nondairy calcium sources was evaluated. Dietary pattern modeling indicated that at least 3 servings of dairy foods are needed to help individuals meet recommendations for nutrients, such as calcium and magnesium, and 4 servings may be needed to help some groups meet potassium recommendations. A calcium-equivalent serving of dairy requires 1.1 servings of fortified soy beverage, 0.6 serving of fortified orange juice, 1.2 servings of bony fish, or 2.2 servings of leafy greens. The replacement of dairy with calcium-equivalent foods alters the overall nutritional profile of the diet and affects nutrients including protein, potassium, magnesium, phosphorus, riboflavin, vitamins A, D and B(12). Similar modeling exercises using consumption data from the National Health and Nutrition Examination Survey also demonstrated that nondairy calcium replacement foods are not a nutritionally equivalent substitute for dairy products. In conclusion, although it is possible to meet calcium intake recommendations without consuming dairy foods, calcium replacement foods are not a nutritionally equivalent substitute for dairy foods and consumption of a calcium-equivalent amount of some nondairy foods is unrealistic. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Examination of Scanner Precision by Analysing Orthodontic Parameters


    Majstorović Nemanja; Čerče Luka; Kramar Davorin; Soković Mirko; Glišić Branislav; Majstorović Vidosav; Živković Srđan


    Background: 3D modelling in orthodontics is becoming an increasingly widespread technique in practice. One of the significant questions already being asked is related to determining the precision of the scanner used for generating surfaces on a 3D model of the jaw.

  7. Examination of Scanner Precision by Analysing Orthodontic Parameters

    Directory of Open Access Journals (Sweden)

    Majstorović Nemanja


    Full Text Available Background: 3D modelling in orthodontics is becoming an increasingly widespread technique in practice. One of the significant questions already being asked is related to determining the precision of the scanner used for generating surfaces on a 3D model of the jaw.

  8. Modelling and analysing oriented fibrous structures

    International Nuclear Information System (INIS)

    Rantala, M; Lassas, M; Siltanen, S; Sampo, J; Takalo, J; Timonen, J


    A mathematical model for fibrous structures using a direction dependent scaling law is presented. The orientation of fibrous nets (e.g. paper) is analysed with a method based on the curvelet transform. The curvelet-based orientation analysis has been tested successfully on real data from paper samples: the major directions of fibrefibre orientation can apparently be recovered. Similar results are achieved in tests on data simulated by the new model, allowing a comparison with ground truth

  9. Modelling and Analysing Socio-Technical Systems

    DEFF Research Database (Denmark)

    Aslanyan, Zaruhi; Ivanova, Marieta Georgieva; Nielson, Flemming


    Modern organisations are complex, socio-technical systems consisting of a mixture of physical infrastructure, human actors, policies and processes. An in-creasing number of attacks on these organisations exploits vulnerabilities on all different levels, for example combining a malware attack...... with social engineering. Due to this combination of attack steps on technical and social levels, risk assessment in socio-technical systems is complex. Therefore, established risk assessment methods often abstract away the internal structure of an organisation and ignore human factors when modelling...... and assessing attacks. In our work we model all relevant levels of socio-technical systems, and propose evaluation techniques for analysing the security properties of the model. Our approach simplifies the identification of possible attacks and provides qualified assessment and ranking of attacks based...

  10. Examination of triacylglycerol biosynthetic pathways via de novo transcriptomic and proteomic analyses in an unsequenced microalga.

    Directory of Open Access Journals (Sweden)

    Michael T Guarnieri

    Full Text Available Biofuels derived from algal lipids represent an opportunity to dramatically impact the global energy demand for transportation fuels. Systems biology analyses of oleaginous algae could greatly accelerate the commercialization of algal-derived biofuels by elucidating the key components involved in lipid productivity and leading to the initiation of hypothesis-driven strain-improvement strategies. However, higher-level systems biology analyses, such as transcriptomics and proteomics, are highly dependent upon available genomic sequence data, and the lack of these data has hindered the pursuit of such analyses for many oleaginous microalgae. In order to examine the triacylglycerol biosynthetic pathway in the unsequenced oleaginous microalga, Chlorella vulgaris, we have established a strategy with which to bypass the necessity for genomic sequence information by using the transcriptome as a guide. Our results indicate an upregulation of both fatty acid and triacylglycerol biosynthetic machinery under oil-accumulating conditions, and demonstrate the utility of a de novo assembled transcriptome as a search model for proteomic analysis of an unsequenced microalga.

  11. Modelling and Analyses of Embedded Systems Design

    DEFF Research Database (Denmark)

    Brekling, Aske Wiid

    We present the MoVES languages: a language with which embedded systems can be specified at a stage in the development process where an application is identified and should be mapped to an execution platform (potentially multi- core). We give a formal model for MoVES that captures and gives......-based verification is a promising approach for assisting developers of embedded systems. We provide examples of system verifications that, in size and complexity, point in the direction of industrially-interesting systems....... semantics to the elements of specifications in the MoVES language. We show that even for seem- ingly simple systems, the complexity of verifying real-time constraints can be overwhelming - but we give an upper limit to the size of the search-space that needs examining. Furthermore, the formal model exposes...

  12. Reading between the Lines: Exploring Methods for Analysing Professional Examiner Feedback Discourse (United States)

    Johnson, Martin


    This paper uses the remote interactions of professional examiners working for a UK-based awarding body as a vehicle for discussing the benefits of the use of different methods for analysing such discourse. Communication is an area of interest for sociocultural theory because it can potentiate cognitive shifts in participants and affords learning.…

  13. Social Network Analyses and Nutritional Behavior: An Integrated Modeling Approach

    Directory of Open Access Journals (Sweden)

    Alistair McNair Senior


    Full Text Available Animals have evolved complex foraging strategies to obtain a nutritionally balanced diet and associated fitness benefits. Recent advances in nutrition research, combining state-space models of nutritional geometry with agent-based models of systems biology, show how nutrient targeted foraging behavior can also influence animal social interactions, ultimately affecting collective dynamics and group structures. Here we demonstrate how social network analyses can be integrated into such a modeling framework and provide a tangible and practical analytical tool to compare experimental results with theory. We illustrate our approach by examining the case of nutritionally mediated dominance hierarchies. First we show how nutritionally explicit agent-based models that simulate the emergence of dominance hierarchies can be used to generate social networks. Importantly the structural properties of our simulated networks bear similarities to dominance networks of real animals (where conflicts are not always directly related to nutrition. Finally, we demonstrate how metrics from social network analyses can be used to predict the fitness of agents in these simulated competitive environments. Our results highlight the potential importance of nutritional mechanisms in shaping dominance interactions in a wide range of social and ecological contexts. Nutrition likely influences social interaction in many species, and yet a theoretical framework for exploring these effects is currently lacking. Combining social network analyses with computational models from nutritional ecology may bridge this divide, representing a pragmatic approach for generating theoretical predictions for nutritional experiments.

  14. Externalizing Behaviour for Analysing System Models

    DEFF Research Database (Denmark)

    Ivanova, Marieta Georgieva; Probst, Christian W.; Hansen, René Rydhof


    System models have recently been introduced to model organisations and evaluate their vulnerability to threats and especially insider threats. Especially for the latter these models are very suitable, since insiders can be assumed to have more knowledge about the attacked organisation than outside......, if not impossible task to change behaviours. Especially when considering social engineering or the human factor in general, the ability to use different kinds of behaviours is essential. In this work we present an approach to make the behaviour a separate component in system models, and explore how to integrate...

  15. Photovoltaic System Modeling. Uncertainty and Sensitivity Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Clifford W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martin, Curtis E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    We report an uncertainty and sensitivity analysis for modeling AC energy from ph otovoltaic systems . Output from a PV system is predicted by a sequence of models. We quantify u ncertainty i n the output of each model using empirical distribution s of each model's residuals. We propagate uncertainty through the sequence of models by sampli ng these distributions to obtain a n empirical distribution of a PV system's output. We consider models that: (1) translate measured global horizontal, direct and global diffuse irradiance to plane - of - array irradiance; (2) estimate effective irradiance; (3) predict cell temperature; (4) estimate DC voltage, current and power ; (5) reduce DC power for losses due to inefficient maximum power point tracking or mismatch among modules; and (6) convert DC to AC power . O ur analysis consider s a notional PV system com prising an array of FirstSolar FS - 387 modules and a 250 kW AC inverter ; we use measured irradiance and weather at Albuquerque, NM. We found the uncertainty in PV syste m output to be relatively small, on the order of 1% for daily energy. We found that unce rtainty in the models for POA irradiance and effective irradiance to be the dominant contributors to uncertainty in predicted daily energy. Our analysis indicates that efforts to reduce the uncertainty in PV system output predictions may yield the greatest improvements by focusing on the POA and effective irradiance models.

  16. Patterns of medicinal plant use: an examination of the Ecuadorian Shuar medicinal flora using contingency table and binomial analyses. (United States)

    Bennett, Bradley C; Husby, Chad E


    Botanical pharmacopoeias are non-random subsets of floras, with some taxonomic groups over- or under-represented. Moerman [Moerman, D.E., 1979. Symbols and selectivity: a statistical analysis of Native American medical ethnobotany, Journal of Ethnopharmacology 1, 111-119] introduced linear regression/residual analysis to examine these patterns. However, regression, the commonly-employed analysis, suffers from several statistical flaws. We use contingency table and binomial analyses to examine patterns of Shuar medicinal plant use (from Amazonian Ecuador). We first analyzed the Shuar data using Moerman's approach, modified to better meet requirements of linear regression analysis. Second, we assessed the exact randomization contingency table test for goodness of fit. Third, we developed a binomial model to test for non-random selection of plants in individual families. Modified regression models (which accommodated assumptions of linear regression) reduced R(2) to from 0.59 to 0.38, but did not eliminate all problems associated with regression analyses. Contingency table analyses revealed that the entire flora departs from the null model of equal proportions of medicinal plants in all families. In the binomial analysis, only 10 angiosperm families (of 115) differed significantly from the null model. These 10 families are largely responsible for patterns seen at higher taxonomic levels. Contingency table and binomial analyses offer an easy and statistically valid alternative to the regression approach.

  17. Examination of Triacylglycerol Biosynthetic Pathways via De Novo Transcriptomic and Proteomic Analyses in an Unsequenced Microalga (United States)


    using a variety of water sources, including fresh, brackish, saline, and waste water [1,4,5]. At current production levels, oleaginous microalgae also...underpinnings of microalgal biology than any other microalga to date. However, this species lacks the intrinsic high-lipid productivity of many oleaginous...Examination of Triacylglycerol Biosynthetic Pathways via De Novo Transcriptomic and Proteomic Analyses in an Unsequenced Microalga Michael T

  18. Radiobiological analyse based on cell cluster models

    International Nuclear Information System (INIS)

    Lin Hui; Jing Jia; Meng Damin; Xu Yuanying; Xu Liangfeng


    The influence of cell cluster dimension on EUD and TCP for targeted radionuclide therapy was studied using the radiobiological method. The radiobiological features of tumor with activity-lack in core were evaluated and analyzed by associating EUD, TCP and SF.The results show that EUD will increase with the increase of tumor dimension under the activity homogeneous distribution. If the extra-cellular activity was taken into consideration, the EUD will increase 47%. Under the activity-lack in tumor center and the requirement of TCP=0.90, the α cross-fire influence of 211 At could make up the maximum(48 μm)3 activity-lack for Nucleus source, but(72 μm)3 for Cytoplasm, Cell Surface, Cell and Voxel sources. In clinic,the physician could prefer the suggested dose of Cell Surface source in case of the future of local tumor control for under-dose. Generally TCP could well exhibit the effect difference between under-dose and due-dose, but not between due-dose and over-dose, which makes TCP more suitable for the therapy plan choice. EUD could well exhibit the difference between different models and activity distributions,which makes it more suitable for the research work. When the user uses EUD to study the influence of activity inhomogeneous distribution, one should keep the consistency of the configuration and volume of the former and the latter models. (authors)

  19. In pursuit of truth: A critical examination of meta-analyses of cognitive behavior therapy. (United States)

    Wampold, Bruce E; Flückiger, Christoph; Del Re, A C; Yulish, Noah E; Frost, Nickolas D; Pace, Brian T; Goldberg, Simon B; Miller, Scott D; Baardseth, Timothy P; Laska, Kevin M; Hilsenroth, Mark J


    Three recent meta-analyses have made the claim, albeit with some caveats, that cognitive-behavioral treatments (CBT) are superior to other psychotherapies, in general or for specific disorders (e.g., social phobia). The purpose of the present article was to examine four issues in meta-analysis that mitigate claims of CBT superiority: (a) effect size, power, and statistical significance, (b) focusing on disorder-specific symptom measures and ignoring other important indicators of psychological functioning, (c) problems inherent in classifying treatments provided in primary studies into classes of treatments, and (d) the inclusion of problematic trials, which biases the results, and the exclusion of trials that fail to find differences among treatments. When these issues are examined, the effects demonstrating the superiority of CBT are small, nonsignificant for the most part, limited to targeted symptoms, or are due to flawed primary studies. Meta-analytic evidence for the superiority of CBT in the three meta-analysis are nonexistent or weak.

  20. Bicycling injury hospitalisation rates in Canadian jurisdictions: analyses examining associations with helmet legislation and mode share (United States)

    Teschke, Kay; Koehoorn, Mieke; Shen, Hui; Dennis, Jessica


    Objectives The purpose of this study was to calculate exposure-based bicycling hospitalisation rates in Canadian jurisdictions with different helmet legislation and bicycling mode shares, and to examine whether the rates were related to these differences. Methods Administrative data on hospital stays for bicycling injuries to 10 body region groups and national survey data on bicycling trips were used to calculate hospitalisation rates. Rates were calculated for 44 sex, age and jurisdiction strata for all injury causes and 22 age and jurisdiction strata for traffic-related injury causes. Inferential analyses examined associations between hospitalisation rates and sex, age group, helmet legislation and bicycling mode share. Results In Canada, over the study period 2006–2011, there was an average of 3690 hospitalisations per year and an estimated 593 million annual trips by bicycle among people 12 years of age and older, for a cycling hospitalisation rate of 622 per 100 million trips (95% CI 611 to 633). Hospitalisation rates varied substantially across the jurisdiction, age and sex strata, but only two characteristics explained this variability. For all injury causes, sex was associated with hospitalisation rates; females had rates consistently lower than males. For traffic-related injury causes, higher cycling mode share was consistently associated with lower hospitalisation rates. Helmet legislation was not associated with hospitalisation rates for brain, head, scalp, skull, face or neck injuries. Conclusions These results suggest that transportation and health policymakers who aim to reduce bicycling injury rates in the population should focus on factors related to increased cycling mode share and female cycling choices. Bicycling routes designed to be physically separated from traffic or along quiet streets fit both these criteria and are associated with lower relative risks of injury. PMID:26525719

  1. Examination of species boundaries in the Acropora cervicornis group (Scleractinia, cnidaria) using nuclear DNA sequence analyses. (United States)

    Oppen, M J; Willis, B L; Vugt, H W; Miller, D J


    Although Acropora is the most species-rich genus of the scleractinian (stony) corals, only three species occur in the Caribbean: A. cervicornis, A. palmata and A. prolifera. Based on overall coral morphology, abundance and distribution patterns, it has been suggested that A. prolifera may be a hybrid between A. cervicornis and A. palmata. The species boundaries among these three morphospecies were examined using DNA sequence analyses of the nuclear Pax-C 46/47 intron and the ribosomal DNA Internal Transcribed Spacer (ITS1 and ITS2) and 5.8S regions. Moderate levels of sequence variability were observed in the ITS and 5.8S sequences (up to 5.2% overall sequence difference), but variability within species was as large as between species and all three species carried similar sequences. Since this is unlikely to represent a shared ancestral polymorphism, the data suggest that introgressive hybridization occurs among the three species. For the Pax-C intron, A. cervicornis and A. palmata had very distinct allele frequencies and A. cervicornis carried a unique allele at a frequency of 0.769 (although sequence differences between alleles were small). All A. prolifera colonies examined were heterozygous for the Pax-C intron, whereas heterozygosity was only 0.286 and 0.333 for A. cervicornis and A. palmata, respectively. These data support the hypothesis that A. prolifera is the product of hybridization between two species that have a different allelic composition for the Pax-C intron, i.e. A. cervicornis and A. palmata. We therefore suggest that A. prolifera is a hybrid between A. cervicornis and A. palmata, which backcrosses with the parental species at low frequency.

  2. Alternative models of DSM-5 PTSD: Examining diagnostic implications. (United States)

    Murphy, Siobhan; Hansen, Maj; Elklit, Ask; Yong Chen, Yoke; Raudzah Ghazali, Siti; Shevlin, Mark


    The factor structure of DSM-5 posttraumatic stress disorder (PTSD) has been extensively debated with evidence supporting the recently proposed seven-factor Hybrid model. However, despite myriad studies examining PTSD symptom structure few have assessed the diagnostic implications of these proposed models. This study aimed to generate PTSD prevalence estimates derived from the 7 alternative factor models and assess whether pre-established risk factors associated with PTSD (e.g., transportation accidents and sexual victimisation) produce consistent risk estimates. Seven alternative models were estimated within a confirmatory factor analytic framework using the PTSD Checklist for DSM-5 (PCL-5). Data were analysed from a Malaysian adolescent community sample (n = 481) of which 61.7% were female, with a mean age of 17.03 years. The results indicated that all models provided satisfactory model fit with statistical superiority for the Externalising Behaviours and seven-factor Hybrid models. The PTSD prevalence estimates varied substantially ranging from 21.8% for the DSM-5 model to 10.0% for the Hybrid model. Estimates of risk associated with PTSD were inconsistent across the alternative models, with substantial variation emerging for sexual victimisation. These findings have important implications for research and practice and highlight that more research attention is needed to examine the diagnostic implications emerging from the alternative models of PTSD. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. VIPRE modeling of VVER-1000 reactor core for DNB analyses

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Y.; Nguyen, Q. [Westinghouse Electric Corporation, Pittsburgh, PA (United States); Cizek, J. [Nuclear Research Institute, Prague, (Czech Republic)


    Based on the one-pass modeling approach, the hot channels and the VVER-1000 reactor core can be modeled in 30 channels for DNB analyses using the VIPRE-01/MOD02 (VIPRE) code (VIPRE is owned by Electric Power Research Institute, Palo Alto, California). The VIPRE one-pass model does not compromise any accuracy in the hot channel local fluid conditions. Extensive qualifications include sensitivity studies of radial noding and crossflow parameters and comparisons with the results from THINC and CALOPEA subchannel codes. The qualifications confirm that the VIPRE code with the Westinghouse modeling method provides good computational performance and accuracy for VVER-1000 DNB analyses.

  4. Seismic Soil-Structure Interaction Analyses of a Deeply Embedded Model Reactor – SASSI Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Nie J.; Braverman J.; Costantino, M.


    This report summarizes the SASSI analyses of a deeply embedded reactor model performed by BNL and CJC and Associates, as part of the seismic soil-structure interaction (SSI) simulation capability project for the NEAMS (Nuclear Energy Advanced Modeling and Simulation) Program of the Department of Energy. The SASSI analyses included three cases: 0.2 g, 0.5 g, and 0.9g, all of which refer to nominal peak accelerations at the top of the bedrock. The analyses utilized the modified subtraction method (MSM) for performing the seismic SSI evaluations. Each case consisted of two analyses: input motion in one horizontal direction (X) and input motion in the vertical direction (Z), both of which utilized the same in-column input motion. Besides providing SASSI results for use in comparison with the time domain SSI results obtained using the DIABLO computer code, this study also leads to the recognition that the frequency-domain method should be modernized so that it can better serve its mission-critical role for analysis and design of nuclear power plants.

  5. Analysing the temporal dynamics of model performance for hydrological models

    NARCIS (Netherlands)

    Reusser, D.E.; Blume, T.; Schaefli, B.; Zehe, E.


    The temporal dynamics of hydrological model performance gives insights into errors that cannot be obtained from global performance measures assigning a single number to the fit of a simulated time series to an observed reference series. These errors can include errors in data, model parameters, or

  6. Modeling Citable Textual Analyses for the Homer Multitext

    Directory of Open Access Journals (Sweden)

    Christopher William Blackwell


    Full Text Available The 'Homer Multitext' project (hmt is documenting the language and structure of Greek epic poetry, and the ancient tradition of commentary on it. The project’s primary data consist of editions of Greek texts; automated and manually created readings analyze the texts across historical and thematic axes. This paper describes an abstract model we follow in documenting an open-ended body of diverse analyses. The analyses apply to passages of texts at different levels of granularity; they may refer to overlapping or mutually exclusive passages of text; and they may apply to non-contiguous passages of text. All are recorded in with explicit, concise, machine-actionable canonical citation of both text passage and analysis in a scheme aligning all analyses to a common notional text. We cite our texts with urns that capture a passage’s position in an 'Ordered Hierarchy of Citation Objects' (ohco2. Analyses are modeled as data-objects with five properties. We create collections of ‘analytical objects’, each uniquely identified by its own urn and each aligned to a particular edition of a text by a urn citation. We can view these analytical objects as an extension of the edition’s citation hierarchy; since they are explicitly ordered by their alignment with the edition they analyze, each collection of analyses meets satisfies the (ohco2 model of a citable text. We call these texts that are derived from and aligned to an edition ‘analytical exemplars’.

  7. Use of flow models to analyse loss of coolant accidents

    International Nuclear Information System (INIS)

    Pinet, Bernard


    This article summarises current work on developing the use of flow models to analyse loss-of-coolant accident in pressurized-water plants. This work is being done jointly, in the context of the LOCA Technical Committee, by the CEA, EDF and FRAMATOME. The construction of the flow model is very closely based on some theoretical studies of the two-fluid model. The laws of transfer at the interface and at the wall are tested experimentally. The representativity of the model then has to be checked in experiments involving several elementary physical phenomena [fr

  8. Response patterns on interview and questionnaire versions of the Eating Disorder Examination and their impact on latent structure analyses. (United States)

    Berg, Kelly C; Swanson, Sonja A; Stiles-Shields, E Colleen; Eddy, Kamryn T; Peterson, Carol B; Le Grange, Daniel


    The purpose of this investigation was to compare the latent structures of the interview (EDE) and questionnaire (EDE-Q) versions of the Eating Disorder Examination. Participants were 280 children, adolescents, and young adults seeking eating disorder treatment. Two separate latent structure analyses (LSAs) were conducted; one used variables from the EDE as indicators and the other used the corresponding variables from the EDE-Q as indicators. The EDE and EDE-Q models both yielded four-class solutions. Three of the four classes from the EDE-Q model demonstrated moderate to high concordance with their paired class from the EDE model. Using the EDE-Q to detect the EDE, the sensitivity and specificity of measuring certain classes varied from poor (18.6%) to excellent (93.7%). The overall concordance was moderate (κ=.49). These data suggest that LSAs using the EDE and EDE-Q may be directly compared; however, differences between results may represent inconsistencies in response patterns rather than true differences in psychopathology. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. SVM models for analysing the headstreams of mine water inrush

    Energy Technology Data Exchange (ETDEWEB)

    Yan Zhi-gang; Du Pei-jun; Guo Da-zhi [China University of Science and Technology, Xuzhou (China). School of Environmental Science and Spatial Informatics


    The support vector machine (SVM) model was introduced to analyse the headstrean of water inrush in a coal mine. The SVM model, based on a hydrogeochemical method, was constructed for recognising two kinds of headstreams and the H-SVMs model was constructed for recognising multi- headstreams. The SVM method was applied to analyse the conditions of two mixed headstreams and the value of the SVM decision function was investigated as a means of denoting the hydrogeochemical abnormality. The experimental results show that the SVM is based on a strict mathematical theory, has a simple structure and a good overall performance. Moreover the parameter W in the decision function can describe the weights of discrimination indices of the headstream of water inrush. The value of the decision function can denote hydrogeochemistry abnormality, which is significant in the prevention of water inrush in a coal mine. 9 refs., 1 fig., 7 tabs.

  10. DNA Analysis and Document Examination: The Impact of Each Technique on Respective Analyses. (United States)

    Parsons, Lauren; Sharfe, Gordon; Vintiner, Sue


    Threatening letters, counterfeit documents, and anonymous notes can commonly be encountered in criminal situations. Such handwritten documents may encourage DNA to transfer from the writer's hands and lower arms when these areas come into contact with the document. As any DNA transferred is likely to be at a low level, sensitive low copy number (LCN) DNA analysis can be employed for testing document exhibits. In this study, we determine locations on the document that are most commonly touched during writing and handling and compare DNA recovery from these sites. We describe the impact of DNA sampling on subsequent document examination techniques including the ESDA(®) and likewise the effect of the ESDA(®) and two other document examination techniques on subsequent DNA analysis. The findings from this study suggest that DNA results can be obtained through targeted sampling of document evidence, but that care is required when ordering these examination strategies. © 2015 American Academy of Forensic Sciences.

  11. Performance of neutron kinetics models for ADS transient analyses

    International Nuclear Information System (INIS)

    Rineiski, A.; Maschek, W.; Rimpault, G.


    Within the framework of the SIMMER code development, neutron kinetics models for simulating transients and hypothetical accidents in advanced reactor systems, in particular in Accelerator Driven Systems (ADSs), have been developed at FZK/IKET in cooperation with CE Cadarache. SIMMER is a fluid-dynamics/thermal-hydraulics code, coupled with a structure model and a space-, time- and energy-dependent neutronics module for analyzing transients and accidents. The advanced kinetics models have also been implemented into KIN3D, a module of the VARIANT/TGV code (stand-alone neutron kinetics) for broadening application and for testing and benchmarking. In the paper, a short review of the SIMMER and KIN3D neutron kinetics models is given. Some typical transients related to ADS perturbations are analyzed. The general models of SIMMER and KIN3D are compared with more simple techniques developed in the context of this work to get a better understanding of the specifics of transients in subcritical systems and to estimate the performance of different kinetics options. These comparisons may also help in elaborating new kinetics models and extending existing computation tools for ADS transient analyses. The traditional point-kinetics model may give rather inaccurate transient reaction rate distributions in an ADS even if the material configuration does not change significantly. This inaccuracy is not related to the problem of choosing a 'right' weighting function: the point-kinetics model with any weighting function cannot take into account pronounced flux shape variations related to possible significant changes in the criticality level or to fast beam trips. To improve the accuracy of the point-kinetics option for slow transients, we have introduced a correction factor technique. The related analyses give a better understanding of 'long-timescale' kinetics phenomena in the subcritical domain and help to evaluate the performance of the quasi-static scheme in a particular case. One

  12. Comparative Analyses of Physics Candidates Scores in West African and National Examinations Councils (United States)

    Utibe, Uduak James; Agah, John Joseph


    The study is a comparative analysis of physics candidates' scores in West African and National Examinations Councils. It also investigates influence of gender. Results of 480 candidates were randomly selected form three randomly selected Senior Science Colleges using the WASSCE and NECOSSCE computer printout sent to the schools, transformed using…

  13. Stardust Interstellar Preliminary Examination V: XRF analyses of interstellar dust candidates at ESRF ID13 (United States)

    Brenker, Frank E.; Westphal, Andrew J.; Vincze, Laszlo; Burghammer, Manfred; Schmitz, Sylvia; Schoonjans, Tom; Silversmit, Geert; Vekemans, Bart; Allen, Carlton; Anderson, David; Ansari, Asna; Bajt, SašA.; Bastien, Ron K.; Bassim, Nabil; Bechtel, Hans A.; Borg, Janet; Bridges, John; Brownlee, Donald E.; Burchell, Mark; Butterworth, Anna L.; Changela, Hitesh; Cloetens, Peter; Davis, Andrew M.; Doll, Ryan; Floss, Christine; Flynn, George; Fougeray, Patrick; Frank, David R.; Gainsforth, Zack; Grün, Eberhard; Heck, Philipp R.; Hillier, Jon K.; Hoppe, Peter; Hudson, Bruce; Huth, Joachim; Hvide, Brit; Kearsley, Anton; King, Ashley J.; Lai, Barry; Leitner, Jan; Lemelle, Laurence; Leroux, Hugues; Leonard, Ariel; Lettieri, Robert; Marchant, William; Nittler, Larry R.; Ogliore, Ryan; Ong, Wei Ja; Postberg, Frank; Price, Mark C.; Sandford, Scott A.; Tresseras, Juan-Angel Sans; Simionovici, Alexandre S.; Solé, Vicente A.; Srama, Ralf; Stadermann, Frank; Stephan, Thomas; Sterken, Veerle J.; Stodolna, Julien; Stroud, Rhonda M.; Sutton, Steven; Trieloff, Mario; Tsou, Peter; Tsuchiyama, Akira; Tyliszczak, Tolek; Korff, Joshua; Wordsworth, Naomi; Zevin, Daniel; Zolensky, Michael E.


    Here, we report analyses by synchrotron X-ray fluorescence microscopy of the elemental composition of eight candidate impact features extracted from the Stardust Interstellar Dust Collector (SIDC). Six of the features were unambiguous tracks, and two were crater-like features. Five of the tracks are so-called "midnight" tracks—that is, they had trajectories consistent with an origin either in the interstellar dust stream or as secondaries from impacts on the Sample Return Capsule (SRC). In a companion paper reporting synchrotron X-ray diffraction analyses of ISPE candidates, we show that two of these particles contain natural crystalline materials: the terminal particle of track 30 contains olivine and spinel, and the terminal particle of track 34 contains olivine. Here, we show that the terminal particle of track 30, Orion, shows elemental abundances, normalized to Fe, that are close to CI values, and a complex, fine-grained structure. The terminal particle of track 34, Hylabrook, shows abundances that deviate strongly from CI, but shows little fine structure and is nearly homogenous. The terminal particles of other midnight tracks, 29 and 37, had heavy element abundances below detection threshold. A third, track 28, showed a composition inconsistent with an extraterrestrial origin, but also inconsistent with known spacecraft materials. A sixth track, with a trajectory consistent with secondary ejecta from an impact on one of the spacecraft solar panels, contains abundant Ce and Zn. This is consistent with the known composition of the glass covering the solar panel. Neither crater-like feature is likely to be associated with extraterrestrial materials. We also analyzed blank aerogel samples to characterize background and variability between aerogel tiles. We found significant differences in contamination levels and compositions, emphasizing the need for local background subtraction for accurate quantification.

  14. Stardust Interstellar Preliminary Examination V: XRF Analyses of Interstellar Dust Candidates at ESRF ID13 (United States)

    Brenker, Frank E.; Westphal, Andrew J.; Simionovici, Alexandre S.; Flynn, George J.; Gainsforth, Zack; Allen, Carlton C.; Sanford, Scott; Zolensky, Michael E.; Bastien, Ron K.; Frank, David R.


    Here, we report analyses by synchrotron X-ray fluorescence microscopy of the elemental composition of eight candidate impact features extracted from the Stardust Interstellar Dust Collector (SIDC). Six of the features were unambiguous tracks, and two were crater-like features. Five of the tracks are so-called midnight tracks that is, they had trajectories consistent with an origin either in the interstellar dust stream or as secondaries from impacts on the Sample Return Capsule (SRC). In a companion paper reporting synchrotron X-ray diffraction analyses of ISPE candidates, we show that two of these particles contain natural crystalline materials: the terminal particle of track 30contains olivine and spinel, and the terminal particle of track 34 contains olivine. Here, we show that the terminal particle of track 30, Orion, shows elemental abundances, normalized to Fe, that are close to CI values, and a complex, fine-grained structure. The terminal particle of track 34, Hylabrook, shows abundances that deviate strongly from CI, but shows little fine structure and is nearly homogenous. The terminal particles of other midnight tracks, 29 and 37, had heavy element abundances below detection threshold. A third, track28, showed a composition inconsistent with an extraterrestrial origin, but also inconsistent with known spacecraft materials. A sixth track, with a trajectory consistent with secondary ejecta from an impact on one of the spacecraft solar panels, contains abundant Ce and Zn. This is consistent with the known composition of the glass covering the solar panel. Neither crater-like feature is likely to be associated with extraterrestrial materials. We also analyzed blank aerogel samples to characterize background and variability between aerogel tiles. We found significant differences in contamination levels and compositions, emphasizing the need for local background subtraction for accurate quantification.

  15. Estimators for longitudinal latent exposure models: examining measurement model assumptions. (United States)

    Sánchez, Brisa N; Kim, Sehee; Sammel, Mary D


    Latent variable (LV) models are increasingly being used in environmental epidemiology as a way to summarize multiple environmental exposures and thus minimize statistical concerns that arise in multiple regression. LV models may be especially useful when multivariate exposures are collected repeatedly over time. LV models can accommodate a variety of assumptions but, at the same time, present the user with many choices for model specification particularly in the case of exposure data collected repeatedly over time. For instance, the user could assume conditional independence of observed exposure biomarkers given the latent exposure and, in the case of longitudinal latent exposure variables, time invariance of the measurement model. Choosing which assumptions to relax is not always straightforward. We were motivated by a study of prenatal lead exposure and mental development, where assumptions of the measurement model for the time-changing longitudinal exposure have appreciable impact on (maximum-likelihood) inferences about the health effects of lead exposure. Although we were not particularly interested in characterizing the change of the LV itself, imposing a longitudinal LV structure on the repeated multivariate exposure measures could result in high efficiency gains for the exposure-disease association. We examine the biases of maximum likelihood estimators when assumptions about the measurement model for the longitudinal latent exposure variable are violated. We adapt existing instrumental variable estimators to the case of longitudinal exposures and propose them as an alternative to estimate the health effects of a time-changing latent predictor. We show that instrumental variable estimators remain unbiased for a wide range of data generating models and have advantages in terms of mean squared error. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  16. Mathematical and Numerical Analyses of Peridynamics for Multiscale Materials Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Du, Qiang [Pennsylvania State Univ., State College, PA (United States)


    The rational design of materials, the development of accurate and efficient material simulation algorithms, and the determination of the response of materials to environments and loads occurring in practice all require an understanding of mechanics at disparate spatial and temporal scales. The project addresses mathematical and numerical analyses for material problems for which relevant scales range from those usually treated by molecular dynamics all the way up to those most often treated by classical elasticity. The prevalent approach towards developing a multiscale material model couples two or more well known models, e.g., molecular dynamics and classical elasticity, each of which is useful at a different scale, creating a multiscale multi-model. However, the challenges behind such a coupling are formidable and largely arise because the atomistic and continuum models employ nonlocal and local models of force, respectively. The project focuses on a multiscale analysis of the peridynamics materials model. Peridynamics can be used as a transition between molecular dynamics and classical elasticity so that the difficulties encountered when directly coupling those two models are mitigated. In addition, in some situations, peridynamics can be used all by itself as a material model that accurately and efficiently captures the behavior of materials over a wide range of spatial and temporal scales. Peridynamics is well suited to these purposes because it employs a nonlocal model of force, analogous to that of molecular dynamics; furthermore, at sufficiently large length scales and assuming smooth deformation, peridynamics can be approximated by classical elasticity. The project will extend the emerging mathematical and numerical analysis of peridynamics. One goal is to develop a peridynamics-enabled multiscale multi-model that potentially provides a new and more extensive mathematical basis for coupling classical elasticity and molecular dynamics, thus enabling next

  17. Integration efficiency for model reduction in micro-mechanical analyses (United States)

    van Tuijl, Rody A.; Remmers, Joris J. C.; Geers, Marc G. D.


    Micro-structural analyses are an important tool to understand material behavior on a macroscopic scale. The analysis of a microstructure is usually computationally very demanding and there are several reduced order modeling techniques available in literature to limit the computational costs of repetitive analyses of a single representative volume element. These techniques to speed up the integration at the micro-scale can be roughly divided into two classes; methods interpolating the integrand and cubature methods. The empirical interpolation method (high-performance reduced order modeling) and the empirical cubature method are assessed in terms of their accuracy in approximating the full-order result. A micro-structural volume element is therefore considered, subjected to four load-cases, including cyclic and path-dependent loading. The differences in approximating the micro- and macroscopic quantities of interest are highlighted, e.g. micro-fluctuations and stresses. Algorithmic speed-ups for both methods with respect to the full-order micro-structural model are quantified. The pros and cons of both classes are thereby clearly identified.

  18. A 1024 channel analyser of model FH 465

    International Nuclear Information System (INIS)

    Tang Cunxun


    The FH 465 is renewed type of the 1024 Channel Analyser of model FH451. Besides simple operation and fine display, featured by the primary one, the core memory is replaced by semiconductor memory; the integration has been improved; employment of 74LS low power consumpted devices widely used in the world has not only greatly decreased the cost, but also can be easily interchanged with Apple-II, Great Wall-0520-CH or IBM-PC/XT Microcomputers. The operating principle, main specifications and test results are described

  19. Analysing earthquake slip models with the spatial prediction comparison test

    KAUST Repository

    Zhang, L.


    Earthquake rupture models inferred from inversions of geophysical and/or geodetic data exhibit remarkable variability due to uncertainties in modelling assumptions, the use of different inversion algorithms, or variations in data selection and data processing. A robust statistical comparison of different rupture models obtained for a single earthquake is needed to quantify the intra-event variability, both for benchmark exercises and for real earthquakes. The same approach may be useful to characterize (dis-)similarities in events that are typically grouped into a common class of events (e.g. moderate-size crustal strike-slip earthquakes or tsunamigenic large subduction earthquakes). For this purpose, we examine the performance of the spatial prediction comparison test (SPCT), a statistical test developed to compare spatial (random) fields by means of a chosen loss function that describes an error relation between a 2-D field (‘model’) and a reference model. We implement and calibrate the SPCT approach for a suite of synthetic 2-D slip distributions, generated as spatial random fields with various characteristics, and then apply the method to results of a benchmark inversion exercise with known solution. We find the SPCT to be sensitive to different spatial correlations lengths, and different heterogeneity levels of the slip distributions. The SPCT approach proves to be a simple and effective tool for ranking the slip models with respect to a reference model.

  20. Multi-state models: metapopulation and life history analyses

    Directory of Open Access Journals (Sweden)

    Arnason, A. N.


    Full Text Available Multi–state models are designed to describe populations that move among a fixed set of categorical states. The obvious application is to population interchange among geographic locations such as breeding sites or feeding areas (e.g., Hestbeck et al., 1991; Blums et al., 2003; Cam et al., 2004 but they are increasingly used to address important questions of evolutionary biology and life history strategies (Nichols & Kendall, 1995. In these applications, the states include life history stages such as breeding states. The multi–state models, by permitting estimation of stage–specific survival and transition rates, can help assess trade–offs between life history mechanisms (e.g. Yoccoz et al., 2000. These trade–offs are also important in meta–population analyses where, for example, the pre–and post–breeding rates of transfer among sub–populations can be analysed in terms of target colony distance, density, and other covariates (e.g., Lebreton et al. 2003; Breton et al., in review. Further examples of the use of multi–state models in analysing dispersal and life–history trade–offs can be found in the session on Migration and Dispersal. In this session, we concentrate on applications that did not involve dispersal. These applications fall in two main categories: those that address life history questions using stage categories, and a more technical use of multi–state models to address problems arising from the violation of mark–recapture assumptions leading to the potential for seriously biased predictions or misleading insights from the models. Our plenary paper, by William Kendall (Kendall, 2004, gives an overview of the use of Multi–state Mark–Recapture (MSMR models to address two such violations. The first is the occurrence of unobservable states that can arise, for example, from temporary emigration or by incomplete sampling coverage of a target population. Such states can also occur for life history reasons, such

  1. Comparison between tests and analyses for ground-foundation models

    International Nuclear Information System (INIS)

    Moriyama, Ken-ichi; Hibino, Hirosi; Izumi, Masanori; Kiya, Yukiharu.


    The laboratory tests were carried out on two ground models made of silicone rubber (hard and soft ground models) and a foundation model made of aluminum in order to confirm the embedment effects on soil-structure interaction system experimentally. The detail of the procedure and the results of the test are described in the companion paper. Up till now, the analytical studies on the embedment effect on seismic response of buildings have been performed in recent years and the analysis tools have been used in the seismic design procedure of the nuclear power plant facilities. The embedment effects on soil-structure interaction system are confirmed by the simulation analysis and the verification of analysis tools are investigated through the simulation analysis in this paper. The following conclusions can be drawn from comparison between laboratory test results and analysis results. (1) The effects of embedment, such as increase in the impedance functions and the rotational component of foundation input motions, were clarified by the simulation analyses and laboratory tests. (2) The analysis results of axisymmetric FEM showed good agreement with processed test results by means of the transient response to eliminate the reflected waves and the analysis tools were confirmed experimentally. (3) The excavated portion of the soil affected the foundation input motion rather than the impedance function since there was little difference between the impedance functions obtained by wave propagation theory and those obtained by the axisymmetric FEM and the rotational component of the foundation input motions increased significantly. (J.P.N.)

  2. A theoretical model for analysing gender bias in medicine

    Directory of Open Access Journals (Sweden)

    Johansson Eva E


    Full Text Available Abstract During the last decades research has reported unmotivated differences in the treatment of women and men in various areas of clinical and academic medicine. There is an ongoing discussion on how to avoid such gender bias. We developed a three-step-theoretical model to understand how gender bias in medicine can occur and be understood. In this paper we present the model and discuss its usefulness in the efforts to avoid gender bias. In the model gender bias is analysed in relation to assumptions concerning difference/sameness and equity/inequity between women and men. Our model illustrates that gender bias in medicine can arise from assuming sameness and/or equity between women and men when there are genuine differences to consider in biology and disease, as well as in life conditions and experiences. However, gender bias can also arise from assuming differences when there are none, when and if dichotomous stereotypes about women and men are understood as valid. This conceptual thinking can be useful for discussing and avoiding gender bias in clinical work, medical education, career opportunities and documents such as research programs and health care policies. Too meet the various forms of gender bias, different facts and measures are needed. Knowledge about biological differences between women and men will not reduce bias caused by gendered stereotypes or by unawareness of health problems and discrimination associated with gender inequity. Such bias reflects unawareness of gendered attitudes and will not change by facts only. We suggest consciousness-rising activities and continuous reflections on gender attitudes among students, teachers, researchers and decision-makers.

  3. A theoretical model for analysing gender bias in medicine. (United States)

    Risberg, Gunilla; Johansson, Eva E; Hamberg, Katarina


    During the last decades research has reported unmotivated differences in the treatment of women and men in various areas of clinical and academic medicine. There is an ongoing discussion on how to avoid such gender bias. We developed a three-step-theoretical model to understand how gender bias in medicine can occur and be understood. In this paper we present the model and discuss its usefulness in the efforts to avoid gender bias. In the model gender bias is analysed in relation to assumptions concerning difference/sameness and equity/inequity between women and men. Our model illustrates that gender bias in medicine can arise from assuming sameness and/or equity between women and men when there are genuine differences to consider in biology and disease, as well as in life conditions and experiences. However, gender bias can also arise from assuming differences when there are none, when and if dichotomous stereotypes about women and men are understood as valid. This conceptual thinking can be useful for discussing and avoiding gender bias in clinical work, medical education, career opportunities and documents such as research programs and health care policies. Too meet the various forms of gender bias, different facts and measures are needed. Knowledge about biological differences between women and men will not reduce bias caused by gendered stereotypes or by unawareness of health problems and discrimination associated with gender inequity. Such bias reflects unawareness of gendered attitudes and will not change by facts only. We suggest consciousness-rising activities and continuous reflections on gender attitudes among students, teachers, researchers and decision-makers.

  4. Comparison of two potato simulation models under climate change. I. Model calibration and sensitivity analyses

    NARCIS (Netherlands)

    Wolf, J.


    To analyse the effects of climate change on potato growth and production, both a simple growth model, POTATOS, and a comprehensive model, NPOTATO, were applied. Both models were calibrated and tested against results from experiments and variety trials in The Netherlands. The sensitivity of model

  5. Examining the Invariance of Holland's Vocational Interest Model across Gender. (United States)

    Anderson, Mary Z.; And Others


    Multiple structural analyses of Strong Interest Inventory General Occupational Themes (GOT) matrices for seven men and seven women indicated GOT correspondence with Holland's circular order and circumplex models. Results suggested that these models are no more or less accurate for men than for women. (SK)

  6. A model finite-element to analyse the mechanical behavior of a PWR fuel rod

    International Nuclear Information System (INIS)

    Galeao, A.C.N.R.; Tanajura, C.A.S.


    A model to analyse the mechanical behavior of a PWR fuel rod is presented. We drew our attention to the phenomenon of pellet-pellet and pellet-cladding contact by taking advantage of an elastic model which include the effects of thermal gradients, cladding internal and external pressures, swelling and initial relocation. The problem of contact gives rise ro a variational formulation which employs Lagrangian multipliers. An iterative scheme is constructed and the finite element method is applied to obtain the numerical solution. Some results and comments are presented to examine the performance of the model. (author) [pt

  7. Impact of sophisticated fog spray models on accident analyses

    International Nuclear Information System (INIS)

    Roblyer, S.P.; Owzarski, P.C.


    The N-Reactor confinement system release dose to the public in a postulated accident is reduced by washing the confinement atmosphere with fog sprays. This allows a low pressure release of confinement atmosphere containing fission products through filters and out an elevated stack. The current accident analysis required revision of the CORRAL code and other codes such as CONTEMPT to properly model the N Reactor confinement into a system of multiple fog-sprayed compartments. In revising these codes, more sophisticated models for the fog sprays and iodine plateout were incorporated to remove some of the conservatism of steam condensing rate, fission product washout and iodine plateout than used in previous studies. The CORRAL code, which was used to describe the transport and deposition of airborne fission products in LWR containment systems for the Rasmussen Study, was revised to describe fog spray removal of molecular iodine (I 2 ) and particulates in multiple compartments for sprays having individual characteristics of on-off times, flow rates, fall heights, and drop sizes in changing containment atmospheres. During postulated accidents, the code determined the fission product removal rates internally rather than from input decontamination factors. A discussion is given of how the calculated plateout and washout rates vary with time throughout the analysis. The results of the accident analyses indicated that more credit could be given to fission product washout and plateout. An important finding was that the release of fission products to the atmosphere and adsorption of fission products on the filters were significantly lower than previous studies had indicated

  8. Comparison of linear measurements and analyses taken from plaster models and three-dimensional images. (United States)

    Porto, Betina Grehs; Porto, Thiago Soares; Silva, Monica Barros; Grehs, Renésio Armindo; Pinto, Ary dos Santos; Bhandi, Shilpa H; Tonetto, Mateus Rodrigues; Bandéca, Matheus Coelho; dos Santos-Pinto, Lourdes Aparecida Martins


    Digital models are an alternative for carrying out analyses and devising treatment plans in orthodontics. The objective of this study was to evaluate the accuracy and the reproducibility of measurements of tooth sizes, interdental distances and analyses of occlusion using plaster models and their digital images. Thirty pairs of plaster models were chosen at random, and the digital images of each plaster model were obtained using a laser scanner (3Shape R-700, 3Shape A/S). With the plaster models, the measurements were taken using a caliper (Mitutoyo Digimatic(®), Mitutoyo (UK) Ltd) and the MicroScribe (MS) 3DX (Immersion, San Jose, Calif). For the digital images, the measurement tools used were those from the O3d software (Widialabs, Brazil). The data obtained were compared statistically using the Dahlberg formula, analysis of variance and the Tukey test (p < 0.05). The majority of the measurements, obtained using the caliper and O3d were identical, and both were significantly different from those obtained using the MS. Intra-examiner agreement was lowest when using the MS. The results demonstrated that the accuracy and reproducibility of the tooth measurements and analyses from the plaster models using the caliper and from the digital models using O3d software were identical.

  9. Mathematical and Numerical Analyses of Peridynamics for Multiscale Materials Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Gunzburger, Max [Florida State Univ., Tallahassee, FL (United States)


    We have treated the modeling, analysis, numerical analysis, and algorithmic development for nonlocal models of diffusion and mechanics. Variational formulations were developed and finite element methods were developed based on those formulations for both steady state and time dependent problems. Obstacle problems and optimization problems for the nonlocal models were also treated and connections made with fractional derivative models.

  10. Improved analyses using function datasets and statistical modeling (United States)

    John S. Hogland; Nathaniel M. Anderson


    Raster modeling is an integral component of spatial analysis. However, conventional raster modeling techniques can require a substantial amount of processing time and storage space and have limited statistical functionality and machine learning algorithms. To address this issue, we developed a new modeling framework using C# and ArcObjects and integrated that framework...

  11. An electrodynamic model to analyse field emission thrusters

    Energy Technology Data Exchange (ETDEWEB)

    Cardelli, E.; Del Zoppo, R.; Venturini, G.


    After a short description of the working principle of field emission thrusters, a surface emission electrodynamic model, capable of describing the required propulsive effects, is shown. The model, developed according to cylindrical geometry, provides one-dimensional differential relations and, therefore, easy resolution. The characteristic curves obtained are graphed. Comparison with experimental data confirms the validity of the proposed model.

  12. A didactic Input-Output model for territorial ecology analyses


    Garry Mcdonald


    This report describes a didactic input-output modelling framework created jointly be the team at REEDS, Universite de Versailles and Dr Garry McDonald, Director, Market Economics Ltd. There are three key outputs associated with this framework: (i) a suite of didactic input-output models developed in Microsoft Excel, (ii) a technical report (this report) which describes the framework and the suite of models1, and (iii) a two week intensive workshop dedicated to the training of REEDS researcher...

  13. Modelling, singular perturbation and bifurcation analyses of bitrophic food chains. (United States)

    Kooi, B W; Poggiale, J C


    Two predator-prey model formulations are studied: for the classical Rosenzweig-MacArthur (RM) model and the Mass Balance (MB) chemostat model. When the growth and loss rate of the predator is much smaller than that of the prey these models are slow-fast systems leading mathematically to singular perturbation problem. In contradiction to the RM-model, the resource for the prey are modelled explicitly in the MB-model but this comes with additional parameters. These parameter values are chosen such that the two models become easy to compare. In both models a transcritical bifurcation, a threshold above which invasion of predator into prey-only system occurs, and the Hopf bifurcation where the interior equilibrium becomes unstable leading to a stable limit cycle. The fast-slow limit cycles are called relaxation oscillations which for increasing differences in time scales leads to the well known degenerated trajectories being concatenations of slow parts of the trajectory and fast parts of the trajectory. In the fast-slow version of the RM-model a canard explosion of the stable limit cycles occurs in the oscillatory region of the parameter space. To our knowledge this type of dynamics has not been observed for the RM-model and not even for more complex ecosystem models. When a bifurcation parameter crosses the Hopf bifurcation point the amplitude of the emerging stable limit cycles increases. However, depending of the perturbation parameter the shape of this limit cycle changes abruptly from one consisting of two concatenated slow and fast episodes with small amplitude of the limit cycle, to a shape with large amplitude of which the shape is similar to the relaxation oscillation, the well known degenerated phase trajectories consisting of four episodes (concatenation of two slow and two fast). The canard explosion point is accurately predicted by using an extended asymptotic expansion technique in the perturbation and bifurcation parameter simultaneously where the small

  14. Analysing the Linux kernel feature model changes using FMDiff

    NARCIS (Netherlands)

    Dintzner, N.J.R.; van Deursen, A.; Pinzger, M.

    Evolving a large scale, highly variable system is a challenging task. For such a system, evolution operations often require to update consistently both their implementation and its feature model. In this context, the evolution of the feature model closely follows the evolution of the system. The

  15. Analysing the Linux kernel feature model changes using FMDiff

    NARCIS (Netherlands)

    Dintzner, N.J.R.; Van Deursen, A.; Pinzger, M.


    Evolving a large scale, highly variable system is a challenging task. For such a system, evolution operations often require to update consistently both their implementation and its feature model. In this context, the evolution of the feature model closely follows the evolution of the system. The

  16. Analysing Models as a Knowledge Technology in Transport Planning

    DEFF Research Database (Denmark)

    Gudmundsson, Henrik


    critical analytic literature on knowledge utilization and policy influence. A simple scheme based in this literature is drawn up to provide a framework for discussing the interface between urban transport planning and model use. A successful example of model use in Stockholm, Sweden is used as a heuristic......Models belong to a wider family of knowledge technologies, applied in the transport area. Models sometimes share with other such technologies the fate of not being used as intended, or not at all. The result may be ill-conceived plans as well as wasted resources. Frequently, the blame...... device to illuminate how such an analytic scheme may allow patterns of insight about the use, influence and role of models in planning to emerge. The main contribution of the paper is to demonstrate that concepts and terminologies from knowledge use literature can provide interpretations of significance...


    International Nuclear Information System (INIS)

    Hansen, P.N.


    This article introduces a GOTHIC version 7.1 model of the Secondary Containment Reactor Building Post LOCA drawdown analysis for a BWR. GOTHIC is an EPRI sponsored thermal hydraulic code. This analysis is required by the Utility to demonstrate an ability to restore and maintain the Secondary Containment Reactor Building negative pressure condition. The technical and regulatory issues associated with this modeling are presented. The analysis includes the affect of wind, elevation and thermal impacts on pressure conditions. The model includes a multiple volume representation which includes the spent fuel pool. In addition, heat sources and sinks are modeled as one dimensional heat conductors. The leakage into the building is modeled to include both laminar as well as turbulent behavior as established by actual plant test data. The GOTHIC code provides components to model heat exchangers used to provide fuel pool cooling as well as area cooling via air coolers. The results of the evaluation are used to demonstrate the time that the Reactor Building is at a pressure that exceeds external conditions. This time period is established with the GOTHIC model based on the worst case pressure conditions on the building. For this time period the Utility must assume the primary containment leakage goes directly to the environment. Once the building pressure is restored below outside conditions the release to the environment can be credited as a filtered release

  18. Plasma-safety assessment model and safety analyses of ITER

    International Nuclear Information System (INIS)

    Honda, T.; Okazaki, T.; Bartels, H.-H.; Uckan, N.A.; Sugihara, M.; Seki, Y.


    A plasma-safety assessment model has been provided on the basis of the plasma physics database of the International Thermonuclear Experimental Reactor (ITER) to analyze events including plasma behavior. The model was implemented in a safety analysis code (SAFALY), which consists of a 0-D dynamic plasma model and a 1-D thermal behavior model of the in-vessel components. Unusual plasma events of ITER, e.g., overfueling, were calculated using the code and plasma burning is found to be self-bounded by operation limits or passively shut down due to impurity ingress from overheated divertor targets. Sudden transition of divertor plasma might lead to failure of the divertor target because of a sharp increase of the heat flux. However, the effects of the aggravating failure can be safely handled by the confinement boundaries. (author)

  19. Modeling theoretical uncertainties in phenomenological analyses for particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Charles, Jerome [CNRS, Aix-Marseille Univ, Universite de Toulon, CPT UMR 7332, Marseille Cedex 9 (France); Descotes-Genon, Sebastien [CNRS, Univ. Paris-Sud, Universite Paris-Saclay, Laboratoire de Physique Theorique (UMR 8627), Orsay Cedex (France); Niess, Valentin [CNRS/IN2P3, UMR 6533, Laboratoire de Physique Corpusculaire, Aubiere Cedex (France); Silva, Luiz Vale [CNRS, Univ. Paris-Sud, Universite Paris-Saclay, Laboratoire de Physique Theorique (UMR 8627), Orsay Cedex (France); Univ. Paris-Sud, CNRS/IN2P3, Universite Paris-Saclay, Groupe de Physique Theorique, Institut de Physique Nucleaire, Orsay Cedex (France); J. Stefan Institute, Jamova 39, P. O. Box 3000, Ljubljana (Slovenia)


    The determination of the fundamental parameters of the Standard Model (and its extensions) is often limited by the presence of statistical and theoretical uncertainties. We present several models for the latter uncertainties (random, nuisance, external) in the frequentist framework, and we derive the corresponding p values. In the case of the nuisance approach where theoretical uncertainties are modeled as biases, we highlight the important, but arbitrary, issue of the range of variation chosen for the bias parameters. We introduce the concept of adaptive p value, which is obtained by adjusting the range of variation for the bias according to the significance considered, and which allows us to tackle metrology and exclusion tests with a single and well-defined unified tool, which exhibits interesting frequentist properties. We discuss how the determination of fundamental parameters is impacted by the model chosen for theoretical uncertainties, illustrating several issues with examples from quark flavor physics. (orig.)

  20. An Examination of Amotivated Students within the Sport Education Model (United States)

    Perlman, Dana


    The purpose of this study was to examine the perceptions and experiences of 33 amotivated students (i.e. students with low levels of motivation) during four consecutive seasons of the Sport Education Model. A qualitative case-study approach was utilized within this study and data was collected using interviews, field notes and reflective journals.…

  1. Examination of Self-Determination within the Sport Education Model (United States)

    Perlman, Dana J.


    The purpose of this study was to examine the influence of the Sport Education Model (SEM) on students' self-determined motivation and underlying psychological need(s) in physical education. A total of 182 Year-9 students were engaged in 20 lesson units of volleyball, using either the SEM or a traditional approach. Data was collected using a…

  2. Compound dislocation models (CDMs) for volcano deformation analyses (United States)

    Nikkhoo, Mehdi; Walter, Thomas R.; Lundgren, Paul R.; Prats-Iraola, Pau


    Volcanic crises are often preceded and accompanied by volcano deformation caused by magmatic and hydrothermal processes. Fast and efficient model identification and parameter estimation techniques for various sources of deformation are crucial for process understanding, volcano hazard assessment and early warning purposes. As a simple model that can be a basis for rapid inversion techniques, we present a compound dislocation model (CDM) that is composed of three mutually orthogonal rectangular dislocations (RDs). We present new RD solutions, which are free of artefact singularities and that also possess full rotational degrees of freedom. The CDM can represent both planar intrusions in the near field and volumetric sources of inflation and deflation in the far field. Therefore, this source model can be applied to shallow dikes and sills, as well as to deep planar and equidimensional sources of any geometry, including oblate, prolate and other triaxial ellipsoidal shapes. In either case the sources may possess any arbitrary orientation in space. After systematically evaluating the CDM, we apply it to the co-eruptive displacements of the 2015 Calbuco eruption observed by the Sentinel-1A satellite in both ascending and descending orbits. The results show that the deformation source is a deflating vertical lens-shaped source at an approximate depth of 8 km centred beneath Calbuco volcano. The parameters of the optimal source model clearly show that it is significantly different from an isotropic point source or a single dislocation model. The Calbuco example reflects the convenience of using the CDM for a rapid interpretation of deformation data.

  3. Model analyses for sustainable energy supply under CO2 restrictions

    International Nuclear Information System (INIS)

    Matsuhashi, Ryuji; Ishitani, Hisashi.


    This paper aims at clarifying key points for realizing sustainable energy supply under restrictions on CO 2 emissions. For this purpose, possibility of solar breeding system is investigated as a key technology for the sustainable energy supply. The authors describe their mathematical model simulating global energy supply and demand in ultra-long term. Depletion of non-renewable resources and constraints on CO 2 emissions are taken into consideration in the model. Computed results have shown that present energy system based on non-renewable resources shifts to a system based on renewable resources in the ultra-long term with appropriate incentives

  4. Vegetable parenting practices scale: Item response modeling analyses (United States)

    Our objective was to evaluate the psychometric properties of a vegetable parenting practices scale using multidimensional polytomous item response modeling which enables assessing item fit to latent variables and the distributional characteristics of the items in comparison to the respondents. We al...

  5. A Hamiltonian approach to model and analyse networks of ...

    Indian Academy of Sciences (India)


    Sep 24, 2015 ... Over the past twelve years, ideas and methods from nonlinear dynamics system theory, in particular, group theoretical methods in bifurcation theory, have been ... In this manuscript, a review of the most recent work on modelling and analysis of two seemingly different systems, an array of gyroscopes and an ...

  6. Gene Discovery and Functional Analyses in the Model Plant Arabidopsis

    DEFF Research Database (Denmark)

    Feng, Cai-ping; Mundy, J.


    The present mini-review describes newer methods and strategies, including transposon and T-DNA insertions, TILLING, Deleteagene, and RNA interference, to functionally analyze genes of interest in the model plant Arabidopsis. The relative advantages and disadvantages of the systems are also...

  7. Capacity allocation in wireless communication networks - models and analyses

    NARCIS (Netherlands)

    Litjens, Remco


    This monograph has concentrated on capacity allocation in cellular and Wireless Local Area Networks, primarily with a network operator’s perspective. In the introduc- tory chapter, a reference model has been proposed for the extensive suite of capacity allocation mechanisms that can be applied at

  8. Theoretical modeling and experimental analyses of laminated wood composite poles (United States)

    Cheng Piao; Todd F. Shupe; Vijaya Gopu; Chung Y. Hse


    Wood laminated composite poles consist of trapezoid-shaped wood strips bonded with synthetic resin. The thick-walled hollow poles had adequate strength and stiffness properties and were a promising substitute for solid wood poles. It was necessary to develop theoretical models to facilitate the manufacture and future installation and maintenance of this novel...

  9. Complex accident scenarios modelled and analysed by Stochastic Petri Nets

    International Nuclear Information System (INIS)

    Nývlt, Ondřej; Haugen, Stein; Ferkl, Lukáš


    This paper is focused on the usage of Petri nets for an effective modelling and simulation of complicated accident scenarios, where an order of events can vary and some events may occur anywhere in an event chain. These cases are hardly manageable by traditional methods as event trees – e.g. one pivotal event must be often inserted several times into one branch of the tree. Our approach is based on Stochastic Petri Nets with Predicates and Assertions and on an idea, which comes from the area of Programmable Logic Controllers: an accidental scenario is described as a net of interconnected blocks, which represent parts of the scenario. So the scenario is firstly divided into parts, which are then modelled by Petri nets. Every block can be easily interconnected with other blocks by input/output variables to create complex ones. In the presented approach, every event or a part of a scenario is modelled only once, independently on a number of its occurrences in the scenario. The final model is much more transparent then the corresponding event tree. The method is shown in two case studies, where the advanced one contains a dynamic behavior. - Highlights: • Event & Fault trees have problems with scenarios where an order of events can vary. • Paper presents a method for modelling and analysis of dynamic accident scenarios. • The presented method is based on Petri nets. • The proposed method solves mentioned problems of traditional approaches. • The method is shown in two case studies: simple and advanced (with dynamic behavior)

  10. A Formal Model to Analyse the Firewall Configuration Errors

    Directory of Open Access Journals (Sweden)

    T. T. Myo


    Full Text Available The firewall is widely known as a brandmauer (security-edge gateway. To provide the demanded security, the firewall has to be appropriately adjusted, i.e. be configured. Unfortunately, when configuring, even the skilled administrators may make mistakes, which result in decreasing level of a network security and network infiltration undesirable packages.The network can be exposed to various threats and attacks. One of the mechanisms used to ensure network security is the firewall.The firewall is a network component, which, using a security policy, controls packages passing through the borders of a secured network. The security policy represents the set of rules.Package filters work in the mode without inspection of a state: they investigate packages as the independent objects. Rules take the following form: (condition, action. The firewall analyses the entering traffic, based on the IP address of the sender and recipient, the port number of the sender and recipient, and the used protocol. When the package meets rule conditions, the action specified in the rule is carried out. It can be: allow, deny.The aim of this article is to develop tools to analyse a firewall configuration with inspection of states. The input data are the file with the set of rules. It is required to submit the analysis of a security policy in an informative graphic form as well as to reveal discrepancy available in rules. The article presents a security policy visualization algorithm and a program, which shows how the firewall rules act on all possible packages. To represent a result in an intelligible form a concept of the equivalence region is introduced.Our task is the program to display results of rules action on the packages in a convenient graphic form as well as to reveal contradictions between the rules. One of problems is the large number of measurements. As it was noted above, the following parameters are specified in the rule: Source IP address, appointment IP

  11. Analyses of homologous rotavirus infection in the mouse model. (United States)

    Burns, J W; Krishnaney, A A; Vo, P T; Rouse, R V; Anderson, L J; Greenberg, H B


    The group A rotaviruses are significant human and veterinary pathogens in terms of morbidity, mortality, and economic loss. Despite its importance, an effective vaccine remains elusive due at least in part to our incomplete understanding of rotavirus immunity and protection. Both large and small animal model systems have been established to address these issues. One significant drawback of these models is the lack of well-characterized wild-type homologous viruses and their cell culture-adapted variants. We have characterized four strains of murine rotaviruses, EC, EHP, EL, and EW, in the infant and adult mouse model using wild-type isolates and cell culture-adapted variants of each strain. Wild-type murine rotaviruses appear to be equally infectious in infant and adult mice in terms of the intensity and duration of virus shedding following primary infection. Spread of infection to naive cagemates is seen in both age groups. Clearance of shedding following primary infection appears to correlate with the development of virus-specific intestinal IgA. Protective immunity is developed in both infant and adult mice following oral infection as demonstrated by a lack of shedding after subsequent wild-type virus challenge. Cell culture-adapted murine rotaviruses appear to be highly attenuated when administered to naive animals and do not spread efficiently to nonimmune cagemates. The availability of these wild-type and cell culture-adapted virus preparations should allow a more systematic evaluation of rotavirus infection and immunity. Furthermore, future vaccine strategies can be evaluated in the mouse model using several fully virulent homologous viruses for challenge.

  12. Analysing the Competency of Mathematical Modelling in Physics


    Redish, Edward F.


    A primary goal of physics is to create mathematical models that allow both predictions and explanations of physical phenomena. We weave maths extensively into our physics instruction beginning in high school, and the level and complexity of the maths we draw on grows as our students progress through a physics curriculum. Despite much research on the learning of both physics and math, the problem of how to successfully teach most of our students to use maths in physics effectively remains unso...

  13. A workflow model to analyse pediatric emergency overcrowding. (United States)

    Zgaya, Hayfa; Ajmi, Ines; Gammoudi, Lotfi; Hammadi, Slim; Martinot, Alain; Beuscart, Régis; Renard, Jean-Marie


    The greatest source of delay in patient flow is the waiting time from the health care request, and especially the bed request to exit from the Pediatric Emergency Department (PED) for hospital admission. It represents 70% of the time that these patients occupied in the PED waiting rooms. Our objective in this study is to identify tension indicators and bottlenecks that contribute to overcrowding. Patient flow mapping through the PED was carried out in a continuous 2 years period from January 2011 to December 2012. Our method is to use the collected real data, basing on accurate visits made in the PED of the Regional University Hospital Center (CHRU) of Lille (France), in order to construct an accurate and complete representation of the PED processes. The result of this representation is a Workflow model of the patient journey in the PED representing most faithfully possible the reality of the PED of CHRU of Lille. This model allowed us to identify sources of delay in patient flow and aspects of the PED activity that could be improved. It must be enough retailed to produce an analysis allowing to identify the dysfunctions of the PED and also to propose and to estimate prevention indicators of tensions. Our survey is integrated into the French National Research Agency project, titled: "Hospital: optimization, simulation and avoidance of strain" (ANR HOST).

  14. An Examination of Models of Relaxation in Complex Systems. I. Continuous Time Random Walk (CTRW) Models. (United States)


    M NRL Memorandum Report 5719 An Examination of Models of Relaxation in Complex Systems 1. Continuous Time Random Walk ( CTRW ) Models K. L. NGAI, R. W...Examination of Models of Relaxation in Complex Systems I. Continuous Time Random Walk ( CTRW ) Models E. PSRSONAL AUTHOR(S) Ntgi, K.L., Rendell. R.W...necessary and idenrify by block number) Models of relaxation in complex systemL based on the continuous time random walk ( CTRW ) formalism are examined on

  15. Genomic, Biochemical, and Modeling Analyses of Asparagine Synthetases from Wheat

    Directory of Open Access Journals (Sweden)

    Hongwei Xu


    Full Text Available Asparagine synthetase activity in cereals has become an important issue with the discovery that free asparagine concentration determines the potential for formation of acrylamide, a probably carcinogenic processing contaminant, in baked cereal products. Asparagine synthetase catalyses the ATP-dependent transfer of the amino group of glutamine to a molecule of aspartate to generate glutamate and asparagine. Here, asparagine synthetase-encoding polymerase chain reaction (PCR products were amplified from wheat (Triticum aestivum cv. Spark cDNA. The encoded proteins were assigned the names TaASN1, TaASN2, and TaASN3 on the basis of comparisons with other wheat and cereal asparagine synthetases. Although very similar to each other they differed slightly in size, with molecular masses of 65.49, 65.06, and 66.24 kDa, respectively. Chromosomal positions and scaffold references were established for TaASN1, TaASN2, and TaASN3, and a fourth, more recently identified gene, TaASN4. TaASN1, TaASN2, and TaASN4 were all found to be single copy genes, located on chromosomes 5, 3, and 4, respectively, of each genome (A, B, and D, although variety Chinese Spring lacked a TaASN2 gene in the B genome. Two copies of TaASN3 were found on chromosome 1 of each genome, and these were given the names TaASN3.1 and TaASN3.2. The TaASN1, TaASN2, and TaASN3 PCR products were heterologously expressed in Escherichia coli (TaASN4 was not investigated in this part of the study. Western blot analysis identified two monoclonal antibodies that recognized the three proteins, but did not distinguish between them, despite being raised to epitopes SKKPRMIEVAAP and GGSNKPGVMNTV in the variable C-terminal regions of the proteins. The heterologously expressed TaASN1 and TaASN2 proteins were found to be active asparagine synthetases, producing asparagine and glutamate from glutamine and aspartate. The asparagine synthetase reaction was modeled using SNOOPY® software and information from

  16. A conceptual model for analysing informal learning in online social networks for health professionals. (United States)

    Li, Xin; Gray, Kathleen; Chang, Shanton; Elliott, Kristine; Barnett, Stephen


    Online social networking (OSN) provides a new way for health professionals to communicate, collaborate and share ideas with each other for informal learning on a massive scale. It has important implications for ongoing efforts to support Continuing Professional Development (CPD) in the health professions. However, the challenge of analysing the data generated in OSNs makes it difficult to understand whether and how they are useful for CPD. This paper presents a conceptual model for using mixed methods to study data from OSNs to examine the efficacy of OSN in supporting informal learning of health professionals. It is expected that using this model with the dataset generated in OSNs for informal learning will produce new and important insights into how well this innovation in CPD is serving professionals and the healthcare system.

  17. Reading Ability Development from Kindergarten to Junior Secondary: Latent Transition Analyses with Growth Mixture Modeling

    Directory of Open Access Journals (Sweden)

    Yuan Liu


    Full Text Available The present study examined the reading ability development of children in the large scale Early Childhood Longitudinal Study (Kindergarten Class of 1998-99 data; Tourangeau, Nord, Lê, Pollack, & Atkins-Burnett, 2006 under the dynamic systems. To depict children's growth pattern, we extended the measurement part of latent transition analysis to the growth mixture model and found that the new model fitted the data well. Results also revealed that most of the children stayed in the same ability group with few cross-level changes in their classes. After adding the environmental factors as predictors, analyses showed that children receiving higher teachers' ratings, with higher socioeconomic status, and of above average poverty status, would have higher probability to transit into the higher ability group.

  18. Longitudinal Data Analyses Using Linear Mixed Models in SPSS: Concepts, Procedures and Illustrations


    Shek, Daniel T. L.; Ma, Cecilia M. S.


    Although different methods are available for the analyses of longitudinal data, analyses based on generalized linear models (GLM) are criticized as violating the assumption of independence of observations. Alternatively, linear mixed models (LMM) are commonly used to understand changes in human behavior over time. In this paper, the basic concepts surrounding LMM (or hierarchical linear models) are outlined. Although SPSS is a statistical analyses package commonly used by researchers, documen...

  19. Using System Dynamic Model and Neural Network Model to Analyse Water Scarcity in Sudan (United States)

    Li, Y.; Tang, C.; Xu, L.; Ye, S.


    Many parts of the world are facing the problem of Water Scarcity. Analysing Water Scarcity quantitatively is an important step to solve the problem. Water scarcity in a region is gauged by WSI (water scarcity index), which incorporate water supply and water demand. To get the WSI, Neural Network Model and SDM (System Dynamic Model) that depict how environmental and social factors affect water supply and demand are developed to depict how environmental and social factors affect water supply and demand. The uneven distribution of water resource and water demand across a region leads to an uneven distribution of WSI within this region. To predict WSI for the future, logistic model, Grey Prediction, and statistics are applied in predicting variables. Sudan suffers from severe water scarcity problem with WSI of 1 in 2014, water resource unevenly distributed. According to the result of modified model, after the intervention, Sudan’s water situation will become better.

  20. Examination of constitutive model for evaluating long-term mechanical behavior of buffer. 3

    International Nuclear Information System (INIS)

    Takaji, Kazuhiko; Shigeno, Yoshimasa; Shimogouchi, Takafumi; Shiratake, Toshikazu; Tamura, Hirokuni


    On the R and D of the high-level radioactive waste repository, it is essential that Engineered Barrier System (EBS) is stable mechanically over a long period of time for maintaining each ability required to EBS. After closing the repository, the various external forces will be affected to buffer intricately for a long period of time. So, to make clear the mechanical deformation behavior of buffer against the external force is important, because of carrying out safety assessment of EBS accurately. In this report, several sets of parameters are chosen for the previously selected two constitutive models, Sekiguchi-Ohta model and Adachi-Oka model, and the element tests and mock-up tests are simulated using these parameters. Through the simulation, applicability of the constitutive models and parameters is examined. Moreover, simulation analyses of EBS using these parameters is examined. Moreover, simulation analyses of EBS using these parameters were carried out, and mechanical behavior is evaluated over a long period of time. Analysis estimated the amount of settlement of the over pack, the stress state of buffer material, the reaction force to a base rock, etc., and the result that EBS is mechanically stable over a long period of time was obtained. Next, in order to prove analyses results a side, literature survey was conducted about geological age, the dynamics history of a Smectite layer. The outline plan was drawn up about the natural analogue verification method and preliminary examination was performed about the applicability of Freezing Sampling'. (author)

  1. Numerical analyses of interaction of steel-fibre reinforced concrete slab model with subsoil

    Directory of Open Access Journals (Sweden)

    Jana Labudkova


    Full Text Available Numerical analyses of contact task were made with FEM. The test sample for the task was a steel-fibre reinforced concrete foundation slab model loaded during experimental loading test. Application of inhomogeneous half-space was used in FEM analyses. Results of FEM analyses were also confronted with the values measured during the experiment.

  2. Comparative examination of two methods for modeling autoimmune uveitis

    Directory of Open Access Journals (Sweden)

    Svetlana V. Aksenova


    Full Text Available Introduction: Uveitis is a disease of the uveal tract, characterized by a variety of causes and clinical manifestations. The internal antigens prevail often in the pathogenesis of the disease and develop the so-called autoimmune reactions. The uveitis treatment has an important medico-social significance because of the high prevalence of uveitis, the significant rate of the disease in young people, and high disability. The article compares the efficiency of two methods for modeling autoimmune uveitis. Materials and Methods: The research was conducted on 6 rabbits of the Chinchilla breed (12 eyes. Two models of experimental uveitis were reproduced on rabbits using normal horse serum during the research. A clinical examination of the inflammatory process course in the eyes was carried out by biomicroscopy using a slit lamp, and a direct ophthalmoscope. Histological and immunological examinations were conducted by the authors of the article. Results: The faster-reproducing and vivid clinical picture of the disease was observed in the second group. The obvious changes in the immunological status of the animals were noted also: an increase in the number of leukocytes, neutrophils, HCT-active neutrophils, and activation of phagocytosis. Discussion and Conclusions: The research has showed that the second model of uveitis is the most convenient working variant, which is characterized by high activity and duration of the inflammatory process in the eye.

  3. Modelling Terminal Examination System For Senior High Schools In Ghana

    Directory of Open Access Journals (Sweden)

    Seidu Azizu


    Full Text Available Modelling terminal examination management system using link softwares for Senior High Schools in Ghana is reported. Both Microsoft Excel and Access were integrated as back and front-end respectively. The two softwares were linked for update of records as well as security purposes during data entry of students records. The link was collapsed after the deadline of data entry to convert the access table to local and enhance data security. Based on the proposed system multiple parameters such as invigilators marks grades attendance and absenteeism were assessed and identified for the various subjects in the entire examination processes. The System applied structured query languagesql for searching specific named parameter for analysis where the total number written papers number of students and performance could also be accessed.

  4. Analyses of tumor-suppressor genes in germline mouse models of cancer. (United States)

    Wang, Jingqiang; Abate-Shen, Cory


    Tumor-suppressor genes are critical regulators of growth and functioning of cells, whose loss of function contributes to tumorigenesis. Accordingly, analyses of the consequences of their loss of function in genetically engineered mouse models have provided important insights into mechanisms of human cancer, as well as resources for preclinical analyses and biomarker discovery. Nowadays, most investigations of genetically engineered mouse models of tumor-suppressor function use conditional or inducible alleles, which enable analyses in specific cancer (tissue) types and overcome the consequences of embryonic lethality of germline loss of function of essential tumor-suppressor genes. However, historically, analyses of genetically engineered mouse models based on germline loss of function of tumor-suppressor genes were very important as these early studies established the principle that loss of function could be studied in mouse cancer models and also enabled analyses of these essential genes in an organismal context. Although the cancer phenotypes of these early germline models did not always recapitulate the expected phenotypes in human cancer, these models provided the essential foundation for the more sophisticated conditional and inducible models that are currently in use. Here, we describe these "first-generation" germline models of loss of function models, focusing on the important lessons learned from their analyses, which helped in the design and analyses of "next-generation" genetically engineered mouse models. © 2014 Cold Spring Harbor Laboratory Press.

  5. Evaluation of Uncertainties in hydrogeological modeling and groundwater flow analyses. Model calibration

    International Nuclear Information System (INIS)

    Ijiri, Yuji; Ono, Makoto; Sugihara, Yutaka; Shimo, Michito; Yamamoto, Hajime; Fumimura, Kenichi


    groundwater has not resulted in reduction of uncertainty only in the calibration of the model using the transient hydraulic data. Therefore, examination of presuming technique of effective porosity and acquisition of direct data by investigation such as tracer examination will be important in the future. (3) In grasping the groundwater flow characteristic efficiently, it is effective to update hydrogeological structure gradually using several modeling techniques with progress of investigation and to feed back the result to investigation. (author)

  6. Mean and Covariance Structures Analyses: An Examination of the Rosenberg Self-Esteem Scale among Adolescents and Adults. (United States)

    Whiteside-Mansell, Leanne; Corwyn, Robert Flynn


    Examined the cross-age comparability of the widely used Rosenberg Self-Esteem Scale (RSES) in 414 adolescents and 900 adults in families receiving Aid to Families with Dependent Children. Found similarities of means in the RSES across groups. (SLD)

  7. Examination of a conceptual model of child neglect. (United States)

    Dubowitz, Howard; Newton, Rae R; Litrownik, Alan J; Lewis, Terri; Briggs, Ernestine C; Thompson, Richard; English, Diana; Lee, Li-Ching; Feerick, Margaret M


    This study attempted to provide empirical support for conceptual definitions of child neglect. We identified 12 types of needs, conceptualizing neglect as occurring when children's basic needs are not adequately met. We examined measures administered to 377 children and caregivers at ages 4 and 6 years participating in longitudinal studies on child mal-treatment to identify potential indicators of these needs. Indicators were found for latent constructs, operationalizing three of the basic needs (emotional support and/or affection, protection from family conflict and/or violence, and from community violence). These latent constructs were used in a measurement model; this supported the conceptual definitions of neglect. A structural equation model then assessed whether the latent constructs were associated with child adjustment at age 8 years. Low level of perceived support from mother was associated with internalizing and externalizing behavior problems. Exposure to family conflict was also linked to these problems, and to social difficulties. Finally, children's sense of experiencing little early affection was associated with subsequent externalizing behavior and social problems. The approach of conceptualizing neglect in terms of unmet child needs, developing a measurement model to define latent neglect constructs, and relating these constructs to subsequent adjustment can build our understanding of neglect.

  8. Examining Asphaltene Solubility on Deposition in Model Porous Media. (United States)

    Lin, Yu-Jiun; He, Peng; Tavakkoli, Mohammad; Mathew, Nevin Thunduvila; Fatt, Yap Yit; Chai, John C; Goharzadeh, Afshin; Vargas, Francisco M; Biswal, Sibani Lisa


    Asphaltenes are known to cause severe flow assurance problems in the near-wellbore region of oil reservoirs. Understanding the mechanism of asphaltene deposition in porous media is of great significance for the development of accurate numerical simulators and effective chemical remediation treatments. Here, we present a study of the dynamics of asphaltene deposition in porous media using microfluidic devices. A model oil containing 5 wt % dissolved asphaltenes was mixed with n-heptane, a known asphaltene precipitant, and flowed through a representative porous media microfluidic chip. Asphaltene deposition was recorded and analyzed as a function of solubility, which was directly correlated to particle size and Péclet number. In particular, pore-scale visualization and velocity profiles, as well as three stages of deposition, were identified and examined to determine the important convection-diffusion effects on deposition.

  9. Examination of Satellite and Model Reanalysis Precipitation with Climate Oscillations (United States)

    Donato, T. F.; Houser, P. R.


    The purpose of this study is to examine the efficacy of satellite and model reanalysis precipitation with climate oscillations. Specifically, we examine and compare the relationship between the Global Precipitation Climate Project (GPCP) with Modern-Era Retrospective Analysis for Research and Application, Version 2 (MERRA-2) in regards to four climate indices: The North Atlantic Oscillation, Southern Oscillation Index, the Southern Annular Mode and Solar Activity. This analysis covers a 35-year observation period from 1980 through 2015. We ask two questions: How is global and regional precipitation changing over the observation period, and how are global and regional variations in precipitation related to global climate variation? We explore and compare global and regional precipitation trends between the two data sets. To do this, we constructed a total of 56 Regions of Interest (ROI). Nineteen of the ROIs were focused on geographic regions including continents, ocean basins, and marginal seas. Twelve ROIs examine hemispheric processes. The remaining 26 regions are derived from spatial-temporal classification analysis of GPCP data over a ten-year period (2001-2010). These regions include the primary wet and dry monsoon regions, regions influenced by western boundary currents, and orography. We investigate and interpret the monthly, seasonal and yearly global and regional response to the selected climate indices. Initial results indicate that no correlation exist between the GPCP data and Merra-2 data. Preliminary qualitative assessment between GCPC and solar activity suggest a possible relationship in intra-annual variability. This work is performed under the State of the Global Water and Energy Cycle (SWEC) project, a NASA-sponsored program in support of NASA's Energy and Water cycle Study (NEWS).

  10. Examination of an eHealth literacy scale and a health literacy scale in a population with moderate to high cardiovascular risk: Rasch analyses.

    Directory of Open Access Journals (Sweden)

    Sarah S Richtering

    Full Text Available Electronic health (eHealth strategies are evolving making it important to have valid scales to assess eHealth and health literacy. Item response theory methods, such as the Rasch measurement model, are increasingly used for the psychometric evaluation of scales. This paper aims to examine the internal construct validity of an eHealth and health literacy scale using Rasch analysis in a population with moderate to high cardiovascular disease risk.The first 397 participants of the CONNECT study completed the electronic health Literacy Scale (eHEALS and the Health Literacy Questionnaire (HLQ. Overall Rasch model fit as well as five key psychometric properties were analysed: unidimensionality, response thresholds, targeting, differential item functioning and internal consistency.The eHEALS had good overall model fit (χ2 = 54.8, p = 0.06, ordered response thresholds, reasonable targeting and good internal consistency (person separation index (PSI 0.90. It did, however, appear to measure two constructs of eHealth literacy. The HLQ subscales (except subscale 5 did not fit the Rasch model (χ2: 18.18-60.60, p: 0.00-0.58 and had suboptimal targeting for most subscales. Subscales 6 to 9 displayed disordered thresholds indicating participants had difficulty distinguishing between response options. All subscales did, nonetheless, demonstrate moderate to good internal consistency (PSI: 0.62-0.82.Rasch analyses demonstrated that the eHEALS has good measures of internal construct validity although it appears to capture different aspects of eHealth literacy (e.g. using eHealth and understanding eHealth. Whilst further studies are required to confirm this finding, it may be necessary for these constructs of the eHEALS to be scored separately. The nine HLQ subscales were shown to measure a single construct of health literacy. However, participants' scores may not represent their actual level of ability, as distinction between response categories was unclear for

  11. Evaluation of Temperature and Humidity Profiles of Unified Model and ECMWF Analyses Using GRUAN Radiosonde Observations

    Directory of Open Access Journals (Sweden)

    Young-Chan Noh


    Full Text Available Temperature and water vapor profiles from the Korea Meteorological Administration (KMA and the United Kingdom Met Office (UKMO Unified Model (UM data assimilation systems and from reanalysis fields from the European Centre for Medium-Range Weather Forecasts (ECMWF were assessed using collocated radiosonde observations from the Global Climate Observing System (GCOS Reference Upper-Air Network (GRUAN for January–December 2012. The motivation was to examine the overall performance of data assimilation outputs. The difference statistics of the collocated model outputs versus the radiosonde observations indicated a good agreement for the temperature, amongst datasets, while less agreement was found for the relative humidity. A comparison of the UM outputs from the UKMO and KMA revealed that they are similar to each other. The introduction of the new version of UM into the KMA in May 2012 resulted in an improved analysis performance, particularly for the moisture field. On the other hand, ECMWF reanalysis data showed slightly reduced performance for relative humidity compared with the UM, with a significant humid bias in the upper troposphere. ECMWF reanalysis temperature fields showed nearly the same performance as the two UM analyses. The root mean square differences (RMSDs of the relative humidity for the three models were larger for more humid conditions, suggesting that humidity forecasts are less reliable under these conditions.

  12. Forensic Image Analyses of Skin and Underlying Muscles as a Tool for Postmortem Interval Delimitation: Histopathologic Examination. (United States)

    El-Nahass, El-Shaymaa; Moselhy, Walaa A; Hassan, Nour El-Houda Y


    One of the biggest challenges for forensic pathologists is to diagnose the postmortem interval (PMI) delimitation; therefore, the aim of this study was to use a routine histopathologic examination and quantitative analysis to obtain an accurate diagnosis of PMI. The current study was done by using 24 adult male albino rats divided into 8 groups based on the scarification schedule (0, 8, 16, 24, 32, 40, 48, and 72 hours PMI). Skin specimens were collected and subjected to a routine histopathologic processing. Examination of hematoxylin-eosin-stained sections from the skin, its appendages and underlying muscles were carried out. Morphometric analysis of epidermal nuclear chromatin intensities and area percentages, reticular dermis integrated density, and sebaceous gland nuclei areas and chromatin condensation was done. Progressive histopathologic changes could be detected in epidermis, dermis, hypodermis, underlying muscles including nerve endings, and red blood cells in relation to hours PMI. Significant difference was found in epidermal nuclear chromatin intensities at different-hours PMI (at P PMI. Quantitative analysis of measurements of dermal collagen area percentages revealed a high significant difference between 0 hours PMI and 24 to 72 hours PMI (P PMI increases, sebaceous gland nuclei and nuclear chromatin condensation showed a dramatic decrease. Significant differences of sebaceous gland nuclei areas between 0 hours and different-hours PMI (P PMI.

  13. Provisional safety analyses for SGT stage 2 -- Models, codes and general modelling approach

    International Nuclear Information System (INIS)


    In the framework of the provisional safety analyses for Stage 2 of the Sectoral Plan for Deep Geological Repositories (SGT), deterministic modelling of radionuclide release from the barrier system along the groundwater pathway during the post-closure period of a deep geological repository is carried out. The calculated radionuclide release rates are interpreted as annual effective dose for an individual and assessed against the regulatory protection criterion 1 of 0.1 mSv per year. These steps are referred to as dose calculations. Furthermore, from the results of the dose calculations so-called characteristic dose intervals are determined, which provide input to the safety-related comparison of the geological siting regions in SGT Stage 2. Finally, the results of the dose calculations are also used to illustrate and to evaluate the post-closure performance of the barrier systems under consideration. The principal objective of this report is to describe comprehensively the technical aspects of the dose calculations. These aspects comprise: · the generic conceptual models of radionuclide release from the solid waste forms, of radionuclide transport through the system of engineered and geological barriers, of radionuclide transfer in the biosphere, as well as of the potential radiation exposure of the population, · the mathematical models for the explicitly considered release and transport processes, as well as for the radiation exposure pathways that are included, · the implementation of the mathematical models in numerical codes, including an overview of these codes and the most relevant verification steps, · the general modelling approach when using the codes, in particular the generic assumptions needed to model the near field and the geosphere, along with some numerical details, · a description of the work flow related to the execution of the calculations and of the software tools that are used to facilitate the modelling process, and · an overview of the

  14. Longitudinal data analyses using linear mixed models in SPSS: concepts, procedures and illustrations. (United States)

    Shek, Daniel T L; Ma, Cecilia M S


    Although different methods are available for the analyses of longitudinal data, analyses based on generalized linear models (GLM) are criticized as violating the assumption of independence of observations. Alternatively, linear mixed models (LMM) are commonly used to understand changes in human behavior over time. In this paper, the basic concepts surrounding LMM (or hierarchical linear models) are outlined. Although SPSS is a statistical analyses package commonly used by researchers, documentation on LMM procedures in SPSS is not thorough or user friendly. With reference to this limitation, the related procedures for performing analyses based on LMM in SPSS are described. To demonstrate the application of LMM analyses in SPSS, findings based on six waves of data collected in the Project P.A.T.H.S. (Positive Adolescent Training through Holistic Social Programmes) in Hong Kong are presented.

  15. An examination of the developmental propensity model of conduct problems. (United States)

    Rhee, Soo Hyun; Friedman, Naomi P; Corley, Robin P; Hewitt, John K; Hink, Laura K; Johnson, Daniel P; Smith Watts, Ashley K; Young, Susan E; Robinson, JoAnn; Waldman, Irwin D; Zahn-Waxler, Carolyn


    The present study tested specific hypotheses advanced by the developmental propensity model of the etiology of conduct problems in the Colorado Longitudinal Twin Study, a prospective, longitudinal, genetically informative sample. High negative emotionality, low behavioral inhibition, low concern and high disregard for others, and low cognitive ability assessed during toddlerhood (age 14 to 36 months) were examined as predictors of conduct problems in later childhood and adolescence (age 4 to 17 years). Each hypothesized antisocial propensity dimension predicted conduct problems, but some predictions may be context specific or due to method covariance. The most robust predictors were observed disregard for others (i.e., responding to others' distress with active, negative responses such as anger and hostility), general cognitive ability, and language ability, which were associated with conduct problems reported by parents, teachers, and adolescents, and change in observed negative emotionality (i.e., frustration tolerance), which was associated with conduct problems reported by teachers and adolescents. Furthermore, associations between the most robust early predictors and later conduct problems were influenced by the shared environment rather than genes. We conclude that shared environmental influences that promote disregard for others and detract from cognitive and language development during toddlerhood also predispose individuals to conduct problems in later childhood and adolescence. The identification of those shared environmental influences common to early antisocial propensity and later conduct problems is an important future direction, and additional developmental behavior genetic studies examining the interaction between children's characteristics and socializing influences on conduct problems are needed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  16. Examining the impact of lahars on buildings using numerical modelling (United States)

    Mead, Stuart R.; Magill, Christina; Lemiale, Vincent; Thouret, Jean-Claude; Prakash, Mahesh


    Lahars are volcanic flows containing a mixture of fluid and sediment which have the potential to cause significant damage to buildings, critical infrastructure and human life. The extent of this damage is controlled by properties of the lahar, location of elements at risk and susceptibility of these elements to the lahar. Here we focus on understanding lahar-induced building damage. Quantification of building damage can be difficult due to the complexity of lahar behaviour (hazard), varying number and type of buildings exposed to the lahar (exposure) and the uncertain susceptibility of buildings to lahar impacts (vulnerability). In this paper, we quantify and examine the importance of lahar hazard, exposure and vulnerability in determining building damage with reference to a case study in the city of Arequipa, Peru. Numerical modelling is used to investigate lahar properties that are important in determining the inundation area and forces applied to buildings. Building vulnerability is quantified through the development of critical depth-pressure curves based on the ultimate bending moment of masonry structures. In the case study area, results suggest that building strength plays a minor role in determining overall building losses in comparison to the effects of building exposure and hydraulic characteristics of the lahar.

  17. Examining the influence of working memory on updating mental models. (United States)

    Valadao, Derick F; Anderson, Britt; Danckert, James


    The ability to accurately build and update mental representations of our environment depends on our ability to integrate information over a variety of time scales and detect changes in the regularity of events. As such, the cognitive mechanisms that support model building and updating are likely to interact with those involved in working memory (WM). To examine this, we performed three experiments that manipulated WM demands concurrently with the need to attend to regularities in other stimulus properties (i.e., location and shape). That is, participants completed a prediction task while simultaneously performing an n-back WM task with either no load or a moderate load. The distribution of target locations (Experiment 1) or shapes (Experiments 2 and 3) included some level of probabilistic regularity, which, unbeknown to participants, changed abruptly within each block. Moderate WM load hampered the ability to benefit from target regularities and to adapt to changes in those regularities (i.e., the prediction task). This was most pronounced when both prediction and WM requirements shared the same target feature. Our results show that representational updating depends on free WM resources in a domain-specific fashion.

  18. An improved lake model for climate simulations: Model structure, evaluation, and sensitivity analyses in CESM1

    Directory of Open Access Journals (Sweden)

    Zachary Subin


    Full Text Available Lakes can influence regional climate, yet most general circulation models have, at best, simple and largely untested representations of lakes. We developed the Lake, Ice, Snow, and Sediment Simulator(LISSS for inclusion in the land-surface component (CLM4 of an earth system model (CESM1. The existing CLM4 lake modelperformed poorly at all sites tested; for temperate lakes, summer surface water temperature predictions were 10–25uC lower than observations. CLM4-LISSS modifies the existing model by including (1 a treatment of snow; (2 freezing, melting, and ice physics; (3 a sediment thermal submodel; (4 spatially variable prescribed lakedepth; (5 improved parameterizations of lake surface properties; (6 increased mixing under ice and in deep lakes; and (7 correction of previous errors. We evaluated the lake model predictions of water temperature and surface fluxes at three small temperate and boreal lakes where extensive observational data was available. We alsoevaluated the predicted water temperature and/or ice and snow thicknesses for ten other lakes where less comprehensive forcing observations were available. CLM4-LISSS performed very well compared to observations for shallow to medium-depth small lakes. For large, deep lakes, the under-prediction of mixing was improved by increasing the lake eddy diffusivity by a factor of 10, consistent with previouspublished analyses. Surface temperature and surface flux predictions were improved when the aerodynamic roughness lengths were calculated as a function of friction velocity, rather than using a constant value of 1 mm or greater. We evaluated the sensitivity of surface energy fluxes to modeled lake processes and parameters. Largechanges in monthly-averaged surface fluxes (up to 30 W m22 were found when excluding snow insulation or phase change physics and when varying the opacity, depth, albedo of melting lake ice, and mixing strength across ranges commonly found in real lakes. Typical

  19. Examining Dense Data Usage near the Regions with Severe Storms in All-Sky Microwave Radiance Data Assimilation and Impacts on GEOS Hurricane Analyses (United States)

    Kim, Min-Jeong; Jin, Jianjun; McCarty, Will; El Akkraoui, Amal; Todling, Ricardo; Gelaro, Ron


    Many numerical weather prediction (NWP) centers assimilate radiances affected by clouds and precipitation from microwave sensors, with the expectation that these data can provide critical constraints on meteorological parameters in dynamically sensitive regions to make significant impacts on forecast accuracy for precipitation. The Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center assimilates all-sky microwave radiance data from various microwave sensors such as all-sky GPM Microwave Imager (GMI) radiance in the Goddard Earth Observing System (GEOS) atmospheric data assimilation system (ADAS), which includes the GEOS atmospheric model, the Gridpoint Statistical Interpolation (GSI) atmospheric analysis system, and the Goddard Aerosol Assimilation System (GAAS). So far, most of NWP centers apply same large data thinning distances, that are used in clear-sky radiance data to avoid correlated observation errors, to all-sky microwave radiance data. For example, NASA GMAO is applying 145 km thinning distances for most of satellite radiance data including microwave radiance data in which all-sky approach is implemented. Even with these coarse observation data usage in all-sky assimilation approach, noticeable positive impacts from all-sky microwave data on hurricane track forecasts were identified in GEOS-5 system. The motivation of this study is based on the dynamic thinning distance method developed in our all-sky framework to use of denser data in cloudy and precipitating regions due to relatively small spatial correlations of observation errors. To investigate the benefits of all-sky microwave radiance on hurricane forecasts, several hurricane cases selected between 2016-2017 are examined. The dynamic thinning distance method is utilized in our all-sky approach to understand the sources and mechanisms to explain the benefits of all-sky microwave radiance data from various microwave radiance sensors like Advanced Microwave Sounder Unit

  20. Global analyses of historical masonry buildings: Equivalent frame vs. 3D solid models (United States)

    Clementi, Francesco; Mezzapelle, Pardo Antonio; Cocchi, Gianmichele; Lenci, Stefano


    The paper analyses the seismic vulnerability of two different masonry buildings. It provides both an advanced 3D modelling with solid elements and an equivalent frame modelling. The global structural behaviour and the dynamic properties of the compound have been evaluated using the Finite Element Modelling (FEM) technique, where the nonlinear behaviour of masonry has been taken into account by proper constitutive assumptions. A sensitivity analysis is done to evaluate the effect of the choice of the structural models.

  1. Random regression analyses using B-splines to model growth of Australian Angus cattle

    Directory of Open Access Journals (Sweden)

    Meyer Karin


    Full Text Available Abstract Regression on the basis function of B-splines has been advocated as an alternative to orthogonal polynomials in random regression analyses. Basic theory of splines in mixed model analyses is reviewed, and estimates from analyses of weights of Australian Angus cattle from birth to 820 days of age are presented. Data comprised 84 533 records on 20 731 animals in 43 herds, with a high proportion of animals with 4 or more weights recorded. Changes in weights with age were modelled through B-splines of age at recording. A total of thirteen analyses, considering different combinations of linear, quadratic and cubic B-splines and up to six knots, were carried out. Results showed good agreement for all ages with many records, but fluctuated where data were sparse. On the whole, analyses using B-splines appeared more robust against "end-of-range" problems and yielded more consistent and accurate estimates of the first eigenfunctions than previous, polynomial analyses. A model fitting quadratic B-splines, with knots at 0, 200, 400, 600 and 821 days and a total of 91 covariance components, appeared to be a good compromise between detailedness of the model, number of parameters to be estimated, plausibility of results, and fit, measured as residual mean square error.


    Directory of Open Access Journals (Sweden)

    Constantin ANGHELACHE


    Full Text Available The article presents the fundamental aspects of the linear regression, as a toolbox which can be used in macroeconomic analyses. The article describes the estimation of the parameters, the statistical tests used, the homoscesasticity and heteroskedasticity. The use of econometrics instrument in macroeconomics is an important factor that guarantees the quality of the models, analyses, results and possible interpretation that can be drawn at this level.

  3. Modern statistical models for forensic fingerprint examinations: a critical review. (United States)

    Abraham, Joshua; Champod, Christophe; Lennard, Chris; Roux, Claude


    Over the last decade, the development of statistical models in support of forensic fingerprint identification has been the subject of increasing research attention, spurned on recently by commentators who claim that the scientific basis for fingerprint identification has not been adequately demonstrated. Such models are increasingly seen as useful tools in support of the fingerprint identification process within or in addition to the ACE-V framework. This paper provides a critical review of recent statistical models from both a practical and theoretical perspective. This includes analysis of models of two different methodologies: Probability of Random Correspondence (PRC) models that focus on calculating probabilities of the occurrence of fingerprint configurations for a given population, and Likelihood Ratio (LR) models which use analysis of corresponding features of fingerprints to derive a likelihood value representing the evidential weighting for a potential source. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Taxing CO2 and subsidising biomass: Analysed in a macroeconomic and sectoral model

    DEFF Research Database (Denmark)

    Klinge Jacobsen, Henrik


    This paper analyses the combination of taxes and subsidies as an instrument to enable a reduction in CO2 emission. The objective of the study is to compare recycling of a CO2 tax revenue as a subsidy for biomass use as opposed to traditional recycling such as reduced income or corporate taxation....... A model of Denmark's energy supply sector is used to analyse the e€ect of a CO2 tax combined with using the tax revenue for biomass subsidies. The energy supply model is linked to a macroeconomic model such that the macroeconomic consequences of tax policies can be analysed along with the consequences...... for speci®c sectors such as agriculture. Electricity and heat are produced at heat and power plants utilising fuels which minimise total fuel cost, while the authorities regulate capacity expansion technologies. The e€ect of fuel taxes and subsidies on fuels is very sensitive to the fuel substitution...

  5. Experimental and Computational Modal Analyses for Launch Vehicle Models considering Liquid Propellant and Flange Joints

    Directory of Open Access Journals (Sweden)

    Chang-Hoon Sim


    Full Text Available In this research, modal tests and analyses are performed for a simplified and scaled first-stage model of a space launch vehicle using liquid propellant. This study aims to establish finite element modeling techniques for computational modal analyses by considering the liquid propellant and flange joints of launch vehicles. The modal tests measure the natural frequencies and mode shapes in the first and second lateral bending modes. As the liquid filling ratio increases, the measured frequencies decrease. In addition, as the number of flange joints increases, the measured natural frequencies increase. Computational modal analyses using the finite element method are conducted. The liquid is modeled by the virtual mass method, and the flange joints are modeled using one-dimensional spring elements along with the node-to-node connection. Comparison of the modal test results and predicted natural frequencies shows good or moderate agreement. The correlation between the modal tests and analyses establishes finite element modeling techniques for modeling the liquid propellant and flange joints of space launch vehicles.

  6. Present status of theories and data analyses of mathematical models for carcinogenesis

    International Nuclear Information System (INIS)

    Kai, Michiaki; Kawaguchi, Isao


    Reviewed are the basic mathematical models (hazard functions), present trend of the model studies and that for radiation carcinogenesis. Hazard functions of carcinogenesis are described for multi-stage model and 2-event model related with cell dynamics. At present, the age distribution of cancer mortality is analyzed, relationship between mutation and carcinogenesis is discussed, and models for colorectal carcinogenesis are presented. As for radiation carcinogenesis, models of Armitage-Doll and of generalized MVK (Moolgavkar, Venson, Knudson, 1971-1990) by 2-stage clonal expansion have been applied to analysis of carcinogenesis in A-bomb survivors, workers in uranium mine (Rn exposure) and smoking doctors in UK and other cases, of which characteristics are discussed. In analyses of A-bomb survivors, models above are applied to solid tumors and leukemia to see the effect, if any, of stage, age of exposure, time progression etc. In miners and smokers, stages of the initiation, promotion and progression in carcinogenesis are discussed on the analyses. Others contain the analyses of workers in Canadian atomic power plant, and of patients who underwent the radiation therapy. Model analysis can help to understand the carcinogenic process in a quantitative aspect rather than to describe the process. (R.T.)


    Energy Technology Data Exchange (ETDEWEB)

    May, E. M.; Rauscher, E. [University of Michigan (United States)


    Circumbinary planets experience a time-varying irradiation pattern as they orbit their two host stars. In this work, we present the first detailed study of the atmospheric effects of this irradiation pattern on known and hypothetical gaseous circumbinary planets. Using both a one-dimensional energy balance model (EBM) and a three-dimensional general circulation model (GCM), we look at the temperature differences between circumbinary planets and their equivalent single-star cases in order to determine the nature of the atmospheres of these planets. We find that for circumbinary planets on stable orbits around their host stars, temperature differences are on average no more than 1.0% in the most extreme cases. Based on detailed modeling with the GCM, we find that these temperature differences are not large enough to excite circulation differences between the two cases. We conclude that gaseous circumbinary planets can be treated as their equivalent single-star case in future atmospheric modeling efforts.

  8. Examining Teacher Outcomes of the School-Wide Positive Behavior Support Model in Norway

    Directory of Open Access Journals (Sweden)

    Mari-Anne Sørlie


    Full Text Available Research on teacher outcomes of the School-Wide Positive Behavior Support (SWPBS model has been scarce. The present study adds to the knowledge base by examining the effects of the Norwegian version of SWPBS (N-PALS on school staffs’ behavior management practices and on their individual and collective efficacy. Questionnaire data were collected from staff and students (Grades 4-7 at four measurement points across four successive school years in 28 intervention schools and 20 comparison schools. Using longitudinal multilevel analyses, indications of positive 3-year main effects of the N-PALS model were observed for staff-reported collective efficacy, self-efficacy, and positive behavior support practices. The intervention effects as measured by Cohen’s d ranged from .14 to .91. The effects on student perceptions of teachers’ behavior management strategies were, however, not consistent with the positive staff ratings. Results are discussed in relation to prior research, future research, and study limitations.

  9. Comparison of plasma input and reference tissue models for analysing [(11)C]flumazenil studies

    NARCIS (Netherlands)

    Klumpers, Ursula M. H.; Veltman, Dick J.; Boellaard, Ronald; Comans, Emile F.; Zuketto, Cassandra; Yaqub, Maqsood; Mourik, Jurgen E. M.; Lubberink, Mark; Hoogendijk, Witte J. G.; Lammertsma, Adriaan A.


    A single-tissue compartment model with plasma input is the established method for analysing [(11)C]flumazenil ([(11)C]FMZ) studies. However, arterial cannulation and measurement of metabolites are time-consuming. Therefore, a reference tissue approach is appealing, but this approach has not been

  10. Kinetic analyses and mathematical modeling of primary photochemical and photoelectrochemical processes in plant photosystems

    NARCIS (Netherlands)

    Vredenberg, W.J.


    In this paper the model and simulation of primary photochemical and photo-electrochemical reactions in dark-adapted intact plant leaves is presented. A descriptive algorithm has been derived from analyses of variable chlorophyll a fluorescence and P700 oxidation kinetics upon excitation with

  11. A Social Development Model of Serious Delinquency: Examining Gender Differences. (United States)

    Laundra, Kenneth H.; Kiger, Gary; Bahr, Stephen J.


    This study offers a critical review and analysis of the Social Development Model and social control theory in delinquency. Results show that attachment and commitment to parents, school, and peers is associated with delinquency for both boys and girls. Parental attachment and commitment play a stronger role in female delinquency, while alienation…

  12. Using Health Belief Model Constructs to Examine Differences (United States)

    Karimy, Mahmood; Azarpira, Hossein; Araban, Marzieh


    Despite documented successful Pap tests in routine care of women, screening levels are unfortunately often lower than recommended. This study aimed to assess differences in adherence to Pap test guidelines among a sample of Iranian women using the Health Belief Model (HBM). In this descriptive and analytical study, information was collected from a total of 305 women, (age range of 15-49) from Zarandieh health centers in Iran using a random multistage sampling method. The questionnaire covered demographic characteristics; health belief model constructs were gathered by a self-report method. The results were analyzed using the independent samples t test and logistic regression in SPSS-20. A total 32% of the subjects had a history of a Pap test and the score mean of the whole constructs model (knowledge, susceptibility, severity, benefits, barriers and self-efficacy) in these individuals was higher than those without a positive history. Among the predictive variables of HBM constructs, the highest weights were observed for perceived benefits ß)=0.36), perceived susceptibility =ß) 0.35) and self-efficacy ß)=0.29). Based on our finding of positive relationships for health belief model structures with performance of a pap smear test, designing educational interventions for changing the knowledge levels and beliefs of women is recommended. Creative Commons Attribution License

  13. Analysing and controlling the tax evasion dynamics via majority-vote model

    International Nuclear Information System (INIS)

    Lima, F W S


    Within the context of agent-based Monte-Carlo simulations, we study the well-known majority-vote model (MVM) with noise applied to tax evasion on simple square lattices, Voronoi-Delaunay random lattices, Barabasi-Albert networks, and Erdoes-Renyi random graphs. In the order to analyse and to control the fluctuations for tax evasion in the economics model proposed by Zaklan, MVM is applied in the neighborhood of the noise critical q c to evolve the Zaklan model. The Zaklan model had been studied recently using the equilibrium Ising model. Here we show that the Zaklan model is robust because this can be studied using equilibrium dynamics of Ising model also through the nonequilibrium MVM and on various topologies cited above giving the same behavior regardless of dynamic or topology used here.

  14. Analysing and controlling the tax evasion dynamics via majority-vote model

    Energy Technology Data Exchange (ETDEWEB)

    Lima, F W S, E-mail:, E-mail: [Departamento de Fisica, Universidade Federal do PiauI, 64049-550, Teresina - PI (Brazil)


    Within the context of agent-based Monte-Carlo simulations, we study the well-known majority-vote model (MVM) with noise applied to tax evasion on simple square lattices, Voronoi-Delaunay random lattices, Barabasi-Albert networks, and Erdoes-Renyi random graphs. In the order to analyse and to control the fluctuations for tax evasion in the economics model proposed by Zaklan, MVM is applied in the neighborhood of the noise critical q{sub c} to evolve the Zaklan model. The Zaklan model had been studied recently using the equilibrium Ising model. Here we show that the Zaklan model is robust because this can be studied using equilibrium dynamics of Ising model also through the nonequilibrium MVM and on various topologies cited above giving the same behavior regardless of dynamic or topology used here.

  15. Integrated freight network model : a GIS-based platform for transportation analyses. (United States)


    The models currently used to examine the behavior transportation systems are usually mode-specific. That is, they focus on a single mode (i.e. railways, highways, or waterways). The lack of : integration limits the usefulness of models to analyze the...

  16. VOC composition of current motor vehicle fuels and vapors, and collinearity analyses for receptor modeling. (United States)

    Chin, Jo-Yu; Batterman, Stuart A


    The formulation of motor vehicle fuels can alter the magnitude and composition of evaporative and exhaust emissions occurring throughout the fuel cycle. Information regarding the volatile organic compound (VOC) composition of motor fuels other than gasoline is scarce, especially for bioethanol and biodiesel blends. This study examines the liquid and vapor (headspace) composition of four contemporary and commercially available fuels: gasoline (gasoline), ultra-low sulfur diesel (ULSD), and B20 (20% soy-biodiesel and 80% ULSD). The composition of gasoline and E85 in both neat fuel and headspace vapor was dominated by aromatics and n-heptane. Despite its low gasoline content, E85 vapor contained higher concentrations of several VOCs than those in gasoline vapor, likely due to adjustments in its formulation. Temperature changes produced greater changes in the partial pressures of 17 VOCs in E85 than in gasoline, and large shifts in the VOC composition. B20 and ULSD were dominated by C(9) to C(16)n-alkanes and low levels of the aromatics, and the two fuels had similar headspace vapor composition and concentrations. While the headspace composition predicted using vapor-liquid equilibrium theory was closely correlated to measurements, E85 vapor concentrations were underpredicted. Based on variance decomposition analyses, gasoline and diesel fuels and their vapors VOC were distinct, but B20 and ULSD fuels and vapors were highly collinear. These results can be used to estimate fuel related emissions and exposures, particularly in receptor models that apportion emission sources, and the collinearity analysis suggests that gasoline- and diesel-related emissions can be distinguished. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Examining the Relationships among Antecedents of Guests’ Behavioural Intentions in Ghana’s Hospitality Industry: A Structural Equation Modelling Approach


    Simon Gyasi Nimako; Anthony Freeman Mensah


    This study empirically examines the critical antecedents of behavioural intentions and the structural interrelationships that exist among the antecedents in the hotel industry in Ghana. The study was a cross-sectional survey of 700 respondents using structured questionnaire personally administered. A usable 359 questionnaire were obtained, representing 51.3% response rate and analysed using Structural Equation Modelling approach. The findings indicate that the proposed model has high goodness...

  18. Problem gambling in adolescents: an examination of the pathways model. (United States)

    Gupta, Rina; Nower, Lia; Derevensky, Jeffrey L; Blaszczynski, Alex; Faregh, Neda; Temcheff, Caroline


    This research tests the applicability of the Integrated Pathways Model for gambling to adolescent problem gamblers, utilizing a cross-sectional design and self-report questionnaires. Although the overall sample consisted of 1,133 adolescents (Quebec: n = 994, 87.7 %; Ontario: n = 139, 12.3 %: Male = 558, 49.5 %; Female = 569, 50.5 %), only problem gamblers were retained in testing the model (N = 109). Personality and clinical features were assessed using the Millon Adolescent Clinical Inventory, attention deficit hyperactivity (ADHD) using the Conners-Wells' Adolescent Self-Report Scale, and the DSM-IV-MR-J and Gambling Activities Questionnaire to determine gambling severity and reasons for gambling. Latent class analysis concluded 5 classes, yet still provided preliminary support for three distinct subgroups similar to those proposed by the Pathways Model, adding a depression only subtype, and a subtype of problem gamblers experiencing both internalizing and externalizing disorders. ADHD symptoms were found to be common to 4 of the 5 classes.

  19. Nurses' intention to leave: critically analyse the theory of reasoned action and organizational commitment model. (United States)

    Liou, Shwu-Ru


    To systematically analyse the Organizational Commitment model and Theory of Reasoned Action and determine concepts that can better explain nurses' intention to leave their job. The Organizational Commitment model and Theory of Reasoned Action have been proposed and applied to understand intention to leave and turnover behaviour, which are major contributors to nursing shortage. However, the appropriateness of applying these two models in nursing was not analysed. Three main criteria of a useful model were used for the analysis: consistency in the use of concepts, testability and predictability. Both theories use concepts consistently. Concepts in the Theory of Reasoned Action are defined broadly whereas they are operationally defined in the Organizational Commitment model. Predictability of the Theory of Reasoned Action is questionable whereas the Organizational Commitment model can be applied to predict intention to leave. A model was proposed based on this analysis. Organizational commitment, intention to leave, work experiences, job characteristics and personal characteristics can be concepts for predicting nurses' intention to leave. Nursing managers may consider nurses' personal characteristics and experiences to increase their organizational commitment and enhance their intention to stay. Empirical studies are needed to test and cross-validate the re-synthesized model for nurses' intention to leave their job.

  20. Analysing, Interpreting, and Testing the Invariance of the Actor-Partner Interdependence Model

    Directory of Open Access Journals (Sweden)

    Gareau, Alexandre


    Full Text Available Although in recent years researchers have begun to utilize dyadic data analyses such as the actor-partner interdependence model (APIM, certain limitations to the applicability of these models still exist. Given the complexity of APIMs, most researchers will often use observed scores to estimate the model's parameters, which can significantly limit and underestimate statistical results. The aim of this article is to highlight the importance of conducting a confirmatory factor analysis (CFA of equivalent constructs between dyad members (i.e. measurement equivalence/invariance; ME/I. Different steps for merging CFA and APIM procedures will be detailed in order to shed light on new and integrative methods.

  1. Joint analyses model for total cholesterol and triglyceride in human serum with near-infrared spectroscopy (United States)

    Yao, Lijun; Lyu, Ning; Chen, Jiemei; Pan, Tao; Yu, Jing


    The development of a small, dedicated near-infrared (NIR) spectrometer has promising potential applications, such as for joint analyses of total cholesterol (TC) and triglyceride (TG) in human serum for preventing and treating hyperlipidemia of a large population. The appropriate wavelength selection is a key technology for developing such a spectrometer. For this reason, a novel wavelength selection method, named the equidistant combination partial least squares (EC-PLS), was applied to the wavelength selection for the NIR analyses of TC and TG in human serum. A rigorous process based on the various divisions of calibration and prediction sets was performed to achieve modeling optimization with stability. By applying EC-PLS, a model set was developed, which consists of various models that were equivalent to the optimal model. The joint analyses model of the two indicators was further selected with only 50 wavelengths. The random validation samples excluded from the modeling process were used to validate the selected model. The root-mean-square errors, correlation coefficients and ratio of performance to deviation for the prediction were 0.197 mmol L- 1, 0.985 and 5.6 for TC, and 0.101 mmol L- 1, 0.992 and 8.0 for TG, respectively. The sensitivity and specificity for hyperlipidemia were 96.2% and 98.0%. These findings indicate high prediction accuracy and low model complexity. The proposed wavelength selection provided valuable references for the designing of a small, dedicated spectrometer for hyperlipidemia. The methodological framework and optimization algorithm are universal, such that they can be applied to other fields.

  2. Distinguishing Mediational Models and Analyses in Clinical Psychology: Atemporal Associations Do Not Imply Causation. (United States)

    Winer, E Samuel; Cervone, Daniel; Bryant, Jessica; McKinney, Cliff; Liu, Richard T; Nadorff, Michael R


    A popular way to attempt to discern causality in clinical psychology is through mediation analysis. However, mediation analysis is sometimes applied to research questions in clinical psychology when inferring causality is impossible. This practice may soon increase with new, readily available, and easy-to-use statistical advances. Thus, we here provide a heuristic to remind clinical psychological scientists of the assumptions of mediation analyses. We describe recent statistical advances and unpack assumptions of causality in mediation, underscoring the importance of time in understanding mediational hypotheses and analyses in clinical psychology. Example analyses demonstrate that statistical mediation can occur despite theoretical mediation being improbable. We propose a delineation of mediational effects derived from cross-sectional designs into the terms temporal and atemporal associations to emphasize time in conceptualizing process models in clinical psychology. The general implications for mediational hypotheses and the temporal frameworks from within which they may be drawn are discussed. © 2016 Wiley Periodicals, Inc.

  3. Examining the exobase approximation: DSMC models of Titan's upper atmosphere (United States)

    Tucker, O. J.; Waalkes, W.; Tenishev, V.; Johnson, R. E.; Bieler, A. M.; Nagy, A. F.


    Chamberlain (1963) developed the so-called exobase approximation for planetary atmospheres below which it is assumed that molecular collisions maintain thermal equilibrium and above which collisions are negligible. Here we present an examination of the exobase approximation applied in the DeLaHaye et al. (2007) study used to extract the energy deposition and non-thermal escape rates from Titan's atmosphere using the INMS data for the TA and T5 Cassini encounters. In that study a Liouville theorem based approach is used to fit the density data for N2 and CH4 assuming an enhanced population of suprathermal molecules (E >> kT) was present at the exobase. The density data was fit in the altitude region of 1450 - 2000 km using a kappa energy distribution to characterize the non-thermal component. Here we again fit the data using the conventional kappa energy distribution function, and then use the Direct Simulation Monte Carlo (DSMC) technique (Bird 1994) to determine the effect of molecular collisions. The results for the fits are used to obtain improved fits compared to the results in DeLaHaye et al. (2007). In addition the collisional and collisionless DSMC results are compared to evaluate the validity of the assumed energy distribution function and the collisionless approximation. We find that differences between fitting procedures to the INMS data carried out within a scale height of the assumed exobase can result in the extraction of very different energy deposition and escape rates. DSMC simulations performed with and without collisions to test the Liouville theorem based approximation show that collisions affect the density and temperature profiles well above the exobase as well as the escape rate. This research was supported by grant NNH12ZDA001N from the NASA ROSES OPR program. The computations were made with NAS computer resources at NASA Ames under GID 26135.

  4. Groundwater flow analyses in preliminary site investigations. Modelling strategy and computer codes

    International Nuclear Information System (INIS)

    Taivassalo, V.; Koskinen, L.; Meling, K.


    The analyses of groundwater flow comprised a part of the preliminary site investigations which were carried out by Teollisuuden Voima Oy (TVO) for five areas in Finland during 1987 -1992. The main objective of the flow analyses was to characterize groundwater flow at the sites. The flow simulations were also used to identify and study uncertainties and inadequacies which are inherent in the results of earlier modelling phases. The flow analyses were performed for flow conditions similar to the present conditions. The modelling approach was based on the concept of an equivalent continuum. Each fracture zone and the rock matrix among the zones was, however, considered separately as a hydrogeologic unit. The numerical calculations were carried out with a computer code package, FEFLOW. The code is based upon the finite element method. With the code two- and one-dimensional elements can also be used by way of embedding them in a three-dimensional element mesh. A set of new algorithms was developed and employed to create element meshes for FEFLOW. The most useful program in the preliminary site investigations was PAAWI, which adds two-dimensional elements for fracture zones to an existing three-dimensional element mesh. The new algorithms reduced significantly the time required to create spatial discretization for complex geometries. Three element meshes were created for each site. The boundaries of the regional models coincide with those of the flow models. (55 refs., 40 figs., 1 tab.)

  5. To transform or not to transform: using generalized linear mixed models to analyse reaction time data (United States)

    Lo, Steson; Andrews, Sally


    Linear mixed-effect models (LMMs) are being increasingly widely used in psychology to analyse multi-level research designs. This feature allows LMMs to address some of the problems identified by Speelman and McGann (2013) about the use of mean data, because they do not average across individual responses. However, recent guidelines for using LMM to analyse skewed reaction time (RT) data collected in many cognitive psychological studies recommend the application of non-linear transformations to satisfy assumptions of normality. Uncritical adoption of this recommendation has important theoretical implications which can yield misleading conclusions. For example, Balota et al. (2013) showed that analyses of raw RT produced additive effects of word frequency and stimulus quality on word identification, which conflicted with the interactive effects observed in analyses of transformed RT. Generalized linear mixed-effect models (GLMM) provide a solution to this problem by satisfying normality assumptions without the need for transformation. This allows differences between individuals to be properly assessed, using the metric most appropriate to the researcher's theoretical context. We outline the major theoretical decisions involved in specifying a GLMM, and illustrate them by reanalysing Balota et al.'s datasets. We then consider the broader benefits of using GLMM to investigate individual differences. PMID:26300841

  6. Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts.

    Energy Technology Data Exchange (ETDEWEB)

    Sevougian, S. David; Freeze, Geoffrey A.; Gardner, William Payton; Hammond, Glenn Edward; Mariner, Paul


    directly, rather than through simplified abstractions. It also a llows for complex representations of the source term, e.g., the explicit representation of many individual waste packages (i.e., meter - scale detail of an entire waste emplacement drift). This report fulfills the Generic Disposal System Analysis Work Packa ge Level 3 Milestone - Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts (M 3 FT - 1 4 SN08080 3 2 ).

  7. Generic uncertainty model for DETRA for environmental consequence analyses. Application and sample outputs

    Energy Technology Data Exchange (ETDEWEB)

    Suolanen, V.; Ilvonen, M. [VTT Energy, Espoo (Finland). Nuclear Energy


    Computer model DETRA applies a dynamic compartment modelling approach. The compartment structure of each considered application can be tailored individually. This flexible modelling method makes it possible that the transfer of radionuclides can be considered in various cases: aquatic environment and related food chains, terrestrial environment, food chains in general and food stuffs, body burden analyses of humans, etc. In the former study on this subject, modernization of the user interface of DETRA code was carried out. This new interface works in Windows environment and the usability of the code has been improved. The objective of this study has been to further develop and diversify the user interface so that also probabilistic uncertainty analyses can be performed by DETRA. The most common probability distributions are available: uniform, truncated Gaussian and triangular. The corresponding logarithmic distributions are also available. All input data related to a considered case can be varied, although this option is seldomly needed. The calculated output values can be selected as monitored values at certain simulation time points defined by the user. The results of a sensitivity run are immediately available after simulation as graphical presentations. These outcomes are distributions generated for varied parameters, density functions of monitored parameters and complementary cumulative density functions (CCDF). An application considered in connection with this work was the estimation of contamination of milk caused by radioactive deposition of Cs (10 kBq(Cs-137)/m{sup 2}). The multi-sequence calculation model applied consisted of a pasture modelling part and a dormant season modelling part. These two sequences were linked periodically simulating the realistic practice of care taking of domestic animals in Finland. The most important parameters were varied in this exercise. The performed diversifying of the user interface of DETRA code seems to provide an

  8. Examination of the interpersonal model of loss of control eating in the laboratory. (United States)

    Shank, Lisa M; Crosby, Ross D; Grammer, Anne Claire; Shomaker, Lauren B; Vannucci, Anna; Burke, Natasha L; Stojek, Monika; Brady, Sheila M; Kozlosky, Merel; Reynolds, James C; Yanovski, Jack A; Tanofsky-Kraff, Marian


    The interpersonal model of loss of control (LOC) eating proposes that interpersonal problems lead to negative affect, which in turn contributes to the onset and/or persistence of LOC eating. Despite preliminary support, there are no data examining the construct validity of the interpersonal model of LOC eating using temporally sensitive reports of social stress, distinct negative affective states, and laboratory energy intake. 117 healthy adolescent girls (BMI: 75th-97th %ile) were recruited for a prevention trial targeting excess weight gain in adolescent girls who reported LOC eating. Prior to the intervention, participants completed questionnaires of recent social stress and consumed lunch from a multi-item laboratory test meal. Immediately before the test meal, participants completed a questionnaire of five negative affective states (anger, confusion, depression, fatigue, anxiety). Bootstrapping mediation models were conducted to evaluate pre-meal negative affect states as explanatory mediators of the association between recent social stress and palatable (desserts and snack-type) food intake. All analyses adjusted for age, race, pubertal stage, height, fat mass percentage, and lean mass. Pre-meal state anxiety was a significant mediator for recent social stress and palatable food intake (ps.05). Pre-meal anxiety appears to be the salient mood state for the interpersonal model among adolescent girls with LOC eating. Interventions that focus on improving both social functioning and anxiety may prove most effective at preventing and/or ameliorating disordered eating and obesity in these adolescents. Published by Elsevier Inc.

  9. BWR Mark III containment analyses using a GOTHIC 8.0 3D model

    International Nuclear Information System (INIS)

    Jimenez, Gonzalo; Serrano, César; Lopez-Alonso, Emma; Molina, M del Carmen; Calvo, Daniel; García, Javier; Queral, César; Zuriaga, J. Vicente; González, Montserrat


    Highlights: • The development of a 3D GOTHIC code model of BWR Mark-III containment is described. • Suppression pool modelling based on the POOLEX STB-20 and STB-16 experimental tests. • LOCA and SBO transient simulated to verify the behaviour of the 3D GOTHIC model. • Comparison between the 3D GOTHIC model and MAAP4.07 model is conducted. • Accurate reproduction of pre severe accident conditions with the 3D GOTHIC model. - Abstract: The purpose of this study is to establish a detailed three-dimensional model of Cofrentes NPP BWR/6 Mark III containment building using the containment code GOTHIC 8.0. This paper presents the model construction, the phenomenology tests conducted and the selected transient for the model evaluation. In order to study the proper settings for the model in the suppression pool, two experiments conducted with the experimental installation POOLEX have been simulated, allowing to obtain a proper behaviour of the model under different suppression pool phenomenology. In the transient analyses, a Loss of Coolant Accident (LOCA) and a Station Blackout (SBO) transient have been performed. The main results of the simulations of those transients were qualitative compared with the results obtained from simulations with MAAP 4.07 Cofrentes NPP model, used by the plant for simulating severe accidents. From this comparison, a verification of the model in terms of pressurization, asymmetric discharges and high pressure release were obtained. The completeness of this model has proved to adequately simulate the thermal hydraulic phenomena which occur in the containment during accidental sequences

  10. Computational model for supporting SHM systems design: Damage identification via numerical analyses (United States)

    Sartorato, Murilo; de Medeiros, Ricardo; Vandepitte, Dirk; Tita, Volnei


    This work presents a computational model to simulate thin structures monitored by piezoelectric sensors in order to support the design of SHM systems, which use vibration based methods. Thus, a new shell finite element model was proposed and implemented via a User ELement subroutine (UEL) into the commercial package ABAQUS™. This model was based on a modified First Order Shear Theory (FOST) for piezoelectric composite laminates. After that, damaged cantilever beams with two piezoelectric sensors in different positions were investigated by using experimental analyses and the proposed computational model. A maximum difference in the magnitude of the FRFs between numerical and experimental analyses of 7.45% was found near the resonance regions. For damage identification, different levels of damage severity were evaluated by seven damage metrics, including one proposed by the present authors. Numerical and experimental damage metrics values were compared, showing a good correlation in terms of tendency. Finally, based on comparisons of numerical and experimental results, it is shown a discussion about the potentials and limitations of the proposed computational model to be used for supporting SHM systems design.

  11. Using Weather Data and Climate Model Output in Economic Analyses of Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Auffhammer, M.; Hsiang, S. M.; Schlenker, W.; Sobel, A.


    Economists are increasingly using weather data and climate model output in analyses of the economic impacts of climate change. This article introduces a set of weather data sets and climate models that are frequently used, discusses the most common mistakes economists make in using these products, and identifies ways to avoid these pitfalls. We first provide an introduction to weather data, including a summary of the types of datasets available, and then discuss five common pitfalls that empirical researchers should be aware of when using historical weather data as explanatory variables in econometric applications. We then provide a brief overview of climate models and discuss two common and significant errors often made by economists when climate model output is used to simulate the future impacts of climate change on an economic outcome of interest.


    Directory of Open Access Journals (Sweden)

    Nataša Štambuk-Cvitanović


    Full Text Available Assuming the necessity of analysis, diagnosis and preservation of existing valuable stone masonry structures and ancient monuments in today European urban cores, numerical modelling become an efficient tool for the structural behaviour investigation. It should be supported by experimentally found input data and taken as a part of general combined approach, particularly non-destructive techniques on the structure/model within it. For the structures or their detail which may require more complex analyses three numerical models based upon finite elements technique are suggested: (1 standard linear model; (2 linear model with contact (interface elements; and (3 non-linear elasto-plastic and orthotropic model. The applicability of these models depend upon the accuracy of the approach or type of the problem, and will be presented on some characteristic samples.

  13. Risk Factor Analyses for the Return of Spontaneous Circulation in the Asphyxiation Cardiac Arrest Porcine Model

    Directory of Open Access Journals (Sweden)

    Cai-Jun Wu


    Full Text Available Background: Animal models of asphyxiation cardiac arrest (ACA are frequently used in basic research to mirror the clinical course of cardiac arrest (CA. The rates of the return of spontaneous circulation (ROSC in ACA animal models are lower than those from studies that have utilized ventricular fibrillation (VF animal models. The purpose of this study was to characterize the factors associated with the ROSC in the ACA porcine model. Methods: Forty-eight healthy miniature pigs underwent endotracheal tube clamping to induce CA. Once induced, CA was maintained untreated for a period of 8 min. Two minutes following the initiation of cardiopulmonary resuscitation (CPR, defibrillation was attempted until ROSC was achieved or the animal died. To assess the factors associated with ROSC in this CA model, logistic regression analyses were performed to analyze gender, the time of preparation, the amplitude spectrum area (AMSA from the beginning of CPR and the pH at the beginning of CPR. A receiver-operating characteristic (ROC curve was used to evaluate the predictive value of AMSA for ROSC. Results: ROSC was only 52.1% successful in this ACA porcine model. The multivariate logistic regression analyses revealed that ROSC significantly depended on the time of preparation, AMSA at the beginning of CPR and pH at the beginning of CPR. The area under the ROC curve in for AMSA at the beginning of CPR was 0.878 successful in predicting ROSC (95% confidence intervals: 0.773∼0.983, and the optimum cut-off value was 15.62 (specificity 95.7% and sensitivity 80.0%. Conclusions: The time of preparation, AMSA and the pH at the beginning of CPR were associated with ROSC in this ACA porcine model. AMSA also predicted the likelihood of ROSC in this ACA animal model.

  14. Integrated Process Model Development and Systems Analyses for the LIFE Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Meier, W R; Anklam, T; Abbott, R; Erlandson, A; Halsey, W; Miles, R; Simon, A J


    We have developed an integrated process model (IPM) for a Laser Inertial Fusion-Fission Energy (LIFE) power plant. The model includes cost and performance algorithms for the major subsystems of the plant, including the laser, fusion target fabrication and injection, fusion-fission chamber (including the tritium and fission fuel blankets), heat transfer and power conversion systems, and other balance of plant systems. The model has been developed in Visual Basic with an Excel spreadsheet user interface in order to allow experts in various aspects of the design to easily integrate their individual modules and provide a convenient, widely accessible platform for conducting the system studies. Subsystem modules vary in level of complexity; some are based on top-down scaling from fission power plant costs (for example, electric plant equipment), while others are bottom-up models based on conceptual designs being developed by LLNL (for example, the fusion-fission chamber and laser systems). The IPM is being used to evaluate design trade-offs, do design optimization, and conduct sensitivity analyses to identify high-leverage areas for R&D. We describe key aspects of the IPM and report on the results of our systems analyses. Designs are compared and evaluated as a function of key design variables such as fusion target yield and pulse repetition rate.

  15. Can the intra-examiner variability of Little's Irregularity Index be improved using 3D digital models of study casts? (United States)

    Dowling, Adam H; Burns, Angus; Macauley, Donal; Garvey, Thérèse M; Fleming, Garry J P


    To compare contact point displacement measurements, used to determine the Little's Irregularity Index (LII) score on study casts and digital models of study casts by an independent examiner. The contact point displacement measurements of the six maxillary anterior labial teeth were measured on ten study casts using digital callipers and their associated digital models using Creo Parametric software on five occasions following scanning using a LAVA Chairside Oral Scanner (LCOS) three-dimensional (3D) intra oral scanner. Means, standard deviations and coefficients of variation (CoV) were determined, data analyses (Pearson's correlation coefficients (PCCs) and Intraclass correlation coefficients (ICCs)) and statistical analyses (three and two-way analyses of variance (ANOVAs) and Independent Sample Student's t-tests) were carried out (p0.978; p0.910; p0.963; p0.986; porthodontic community be identified or a new method for measuring anterior incisor crowding be sought. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Examining Variability in Model Skill During the 7 January 2013 Sudden Stratospheric Warming Event (United States)

    Blufer, Jonathan L.

    Recent analyses of numerical weather prediction models have shown that stratospheric regime changes (e.g. strong and weak vortex events) are not skillfully predicted at medium-range lead times. Motivated by these recent analyses, this thesis investigates the sources of variability in stratospheric forecast skill amongst several operational models initiated at different lead times prior to the 7 January 2013 sudden stratospheric warming (SSW). This study extends upon a previous analysis by the Stratospheric Network for the Assessment of Predictability (SNAP), which concluded that a change in forecast lead-time from 15 to 10 days increased model skill in predicting the 2013 SSW by roughly 50 percent. The sources of such variability in predictive skill are investigated further in this thesis. Coordinated reforecasts from the SNAP dataset are used to examine model variability and forecast skill in six medium-range operational ensemble forecast models. Both elliptical diagnostics of the polar vortex that quantify the vortex eccentricity, center longitude and latitude, and area, as well as zonal mean metrics are used to assess model errors and biases in the stratosphere. Ensemble skill is categorized into low and high error composite groups according to two separate metrics: the strength of the 10-hPa zonal mean zonal wind at 60?N and the center latitude of the 10-hPa vortex ellipse. Analysis reveals that ensemble members forecasting an ellipse center located equatorward of 70°N prior to 7 January 2013 had greater skill in predicting an easterly 10-hPa zonal mean zonal wind regime at the time of verified SSW onset. It is hypothesized that model error in forecasting thermodynamic processes linked to the SSW precursor tropospheric blocking in the N. Atlantic resulted in systematic biases and variability in dynamical forcing (e.g. upward wave activity flux) into the polar stratosphere in forecasts of the 7 January 2013 SSW event. Results indicate that errors in maintaining

  17. Interpreting Mini-Mental State Examination Performance in Highly Proficient Bilingual Spanish-English and Asian Indian-English Speakers: Demographic Adjustments, Item Analyses, and Supplemental Measures. (United States)

    Milman, Lisa H; Faroqi-Shah, Yasmeen; Corcoran, Chris D; Damele, Deanna M


    Performance on the Mini-Mental State Examination (MMSE), among the most widely used global screens of adult cognitive status, is affected by demographic variables including age, education, and ethnicity. This study extends prior research by examining the specific effects of bilingualism on MMSE performance. Sixty independent community-dwelling monolingual and bilingual adults were recruited from eastern and western regions of the United States in this cross-sectional group study. Independent sample t tests were used to compare 2 bilingual groups (Spanish-English and Asian Indian-English) with matched monolingual speakers on the MMSE, demographically adjusted MMSE scores, MMSE item scores, and a nonverbal cognitive measure. Regression analyses were also performed to determine whether language proficiency predicted MMSE performance in both groups of bilingual speakers. Group differences were evident on the MMSE, on demographically adjusted MMSE scores, and on a small subset of individual MMSE items. Scores on a standardized screen of language proficiency predicted a significant proportion of the variance in the MMSE scores of both bilingual groups. Bilingual speakers demonstrated distinct performance profiles on the MMSE. Results suggest that supplementing the MMSE with a language screen, administering a nonverbal measure, and/or evaluating item-based patterns of performance may assist with test interpretation for this population.

  18. Considerations when loading spinal finite element models with predicted muscle forces from inverse static analyses. (United States)

    Zhu, Rui; Zander, Thomas; Dreischarf, Marcel; Duda, Georg N; Rohlmann, Antonius; Schmidt, Hendrik


    Mostly simplified loads were used in biomechanical finite element (FE) studies of the spine because of a lack of data on muscular physiological loading. Inverse static (IS) models allow the prediction of muscle forces for predefined postures. A combination of both mechanical approaches - FE and IS - appears to allow a more realistic modeling. However, it is unknown what deviations are to be expected when muscle forces calculated for models with rigid vertebrae and fixed centers of rotation, as generally found in IS models, are applied to a FE model with elastic vertebrae and discs. The aim of this study was to determine the effects of these disagreements. Muscle forces were estimated for 20° flexion and 10° extension in an IS model and transferred to a FE model. The effects of the elasticity of bony structures (rigid vs. elastic) and the definition of the center of rotation (fixed vs. non-fixed) were quantified using the deviation of actual intervertebral rotation (IVR) of the FE model and the targeted IVR from the IS model. For extension, the elasticity of the vertebrae had only a minor effect on IVRs, whereas a non-fixed center of rotation increased the IVR deviation on average by 0.5° per segment. For flexion, a combination of the two parameters increased IVR deviation on average by 1° per segment. When loading FE models with predicted muscle forces from IS analyses, the main limitations in the IS model - rigidity of the segments and the fixed centers of rotation - must be considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Multi-model finite element scheme for static and free vibration analyses of composite laminated beams

    Directory of Open Access Journals (Sweden)

    U.N. Band

    Full Text Available Abstract A transition element is developed for the local global analysis of laminated composite beams. It bridges one part of the domain modelled with a higher order theory and other with a 2D mixed layerwise theory (LWT used at critical zone of the domain. The use of developed transition element makes the analysis for interlaminar stresses possible with significant accuracy. The mixed 2D model incorporates the transverse normal and shear stresses as nodal degrees of freedom (DOF which inherently ensures continuity of these stresses. Non critical zones are modelled with higher order equivalent single layer (ESL theory leading to the global mesh with multiple models applied simultaneously. Use of higher order ESL in non critical zones reduces the total number of elements required to map the domain. A substantial reduction in DOF as compared to a complete 2D mixed model is obvious. This computationally economical multiple modelling scheme using the transition element is applied to static and free vibration analyses of laminated composite beams. Results obtained are in good agreement with benchmarks available in literature.

  20. Examining Factors Affecting Science Achievement of Hong Kong in PISA 2006 Using Hierarchical Linear Modeling (United States)

    Lam, Terence Yuk Ping; Lau, Kwok Chi


    This study uses hierarchical linear modeling to examine the influence of a range of factors on the science performances of Hong Kong students in PISA 2006. Hong Kong has been consistently ranked highly in international science assessments, such as Programme for International Student Assessment and Trends in International Mathematics and Science Study; therefore, an exploration of the factors that affect science performances of Hong Kong students can give a lens to examine how science education can be improved in Hong Kong and other countries. The analyses reveal that student backgrounds as male, at higher grade levels, and born in mainland (when in the same grade) are associated with better science performance. Among the attitudinal factors, enjoyment of science and self-efficacy in science play important roles in scientific achievements. Most of the parental factors, on the other hand, are not having significant impacts on achievement after student attitudes are taken into account, with only parents' value of science having a small effect. School student intake is found to be a strong predictor of school average achievement, as well as a major mediator of the effects of school enrollment size and school socio-economic status. The findings differ from recently reported results, which suggested that school enrollment size was associated with achievement. This study also points out the problems of the use of science instruction time as a school-level variable to explain science achievement in Hong Kong.

  1. A chip-level modeling approach for rail span collapse and survivability analyses

    International Nuclear Information System (INIS)

    Marvis, D.G.; Alexander, D.R.; Dinger, G.L.


    A general semiautomated analysis technique has been developed for analyzing rail span collapse and survivability of VLSI microcircuits in high ionizing dose rate radiation environments. Hierarchical macrocell modeling permits analyses at the chip level and interactive graphical postprocessing provides a rapid visualization of voltage, current and power distributions over an entire VLSIC. The technique is demonstrated for a 16k C MOS/SOI SRAM and a CMOS/SOS 8-bit multiplier. The authors also present an efficient method to treat memory arrays as well as a three-dimensional integration technique to compute sapphire photoconduction from the design layout

  2. Analyses and testing of model prestressed concrete reactor vessels with built-in planes of weakness

    International Nuclear Information System (INIS)

    Dawson, P.; Paton, A.A.; Fleischer, C.C.


    This paper describes the design, construction, analyses and testing of two small scale, single cavity prestressed concrete reactor vessel models, one without planes of weakness and one with planes of weakness immediately behind the cavity liner. This work was carried out to extend a previous study which had suggested the likely feasibility of constructing regions of prestressed concrete reactor vessels and biological shields, which become activated, using easily removable blocks, separated by a suitable membrane. The paper describes the results obtained and concludes that the planes of weakness concept could offer a means of facilitating the dismantling of activated regions of prestressed concrete reactor vessels, biological shields and similar types of structure. (author)

  3. Incorporating uncertainty of management costs in sensitivity analyses of matrix population models. (United States)

    Salomon, Yacov; McCarthy, Michael A; Taylor, Peter; Wintle, Brendan A


    The importance of accounting for economic costs when making environmental-management decisions subject to resource constraints has been increasingly recognized in recent years. In contrast, uncertainty associated with such costs has often been ignored. We developed a method, on the basis of economic theory, that accounts for the uncertainty in population-management decisions. We considered the case where, rather than taking fixed values, model parameters are random variables that represent the situation when parameters are not precisely known. Hence, the outcome is not precisely known either. Instead of maximizing the expected outcome, we maximized the probability of obtaining an outcome above a threshold of acceptability. We derived explicit analytical expressions for the optimal allocation and its associated probability, as a function of the threshold of acceptability, where the model parameters were distributed according to normal and uniform distributions. To illustrate our approach we revisited a previous study that incorporated cost-efficiency analyses in management decisions that were based on perturbation analyses of matrix population models. Incorporating derivations from this study into our framework, we extended the model to address potential uncertainties. We then applied these results to 2 case studies: management of a Koala (Phascolarctos cinereus) population and conservation of an olive ridley sea turtle (Lepidochelys olivacea) population. For low aspirations, that is, when the threshold of acceptability is relatively low, the optimal strategy was obtained by diversifying the allocation of funds. Conversely, for high aspirations, the budget was directed toward management actions with the highest potential effect on the population. The exact optimal allocation was sensitive to the choice of uncertainty model. Our results highlight the importance of accounting for uncertainty when making decisions and suggest that more effort should be placed on

  4. Sensitivity analyses of a global flood model in different geoclimatic regions (United States)

    Moylan, C.; Neal, J. C.; Freer, J. E.; Pianosi, F.; Wagener, T.; Sampson, C. C.; Smith, A.


    Flood models producing global hazard maps now exist, although with significant variation in the modelled hazard extent. Besides explicit structural differences, reasons for this variation is unknown. Understanding the behaviour of these global flood models is necessary to determine how they can be further developed. Preliminary sensitivity analysis was performed using Morris method on the Bristol global flood model, which has 37 parameters, required to translate the remotely sensed data into input for the underlying hydrodynamic model. This number of parameters implies an excess of complexity for flood modelling and should ideally be mitigated. The analysis showed an order of magnitude difference in parameter sensitivities, when comparing total flooded extent. It also showed the most important parameters' influence to be highly interactive rather than just direct; there were surprises in expectation of which parameters are the most important. Despite these findings, conclusions about the model are limited due to the fixed geoclimatic features of the location analysed. Hence more locations with varied geoclimatic characteristics must be chosen, so the consistencies and deviations of parameter sensitivities across these features become quantifiable. Locations are selected using a novel sampling technique, which aggregates the input data of a domain into representative metrics of the geoclimatic features, hypothesised to correlate with one or more parameters. Combinations of these metrics are sampled across a range of geoclimatic areas, and the sensitivities found are correlated with the sampled metrics. From this work, we find the main influences on flood risk prediction at the global scale for the used model structure, which as a methodology is transferable to the other global flood models.

  5. Analysing the Effects of Flood-Resilience Technologies in Urban Areas Using a Synthetic Model Approach

    Directory of Open Access Journals (Sweden)

    Reinhard Schinke


    Full Text Available Flood protection systems with their spatial effects play an important role in managing and reducing flood risks. The planning and decision process as well as the technical implementation are well organized and often exercised. However, building-related flood-resilience technologies (FReT are often neglected due to the absence of suitable approaches to analyse and to integrate such measures in large-scale flood damage mitigation concepts. Against this backdrop, a synthetic model-approach was extended by few complementary methodical steps in order to calculate flood damage to buildings considering the effects of building-related FReT and to analyse the area-related reduction of flood risks by geo-information systems (GIS with high spatial resolution. It includes a civil engineering based investigation of characteristic properties with its building construction including a selection and combination of appropriate FReT as a basis for derivation of synthetic depth-damage functions. Depending on the real exposition and the implementation level of FReT, the functions can be used and allocated in spatial damage and risk analyses. The application of the extended approach is shown at a case study in Valencia (Spain. In this way, the overall research findings improve the integration of FReT in flood risk management. They provide also some useful information for advising of individuals at risk supporting the selection and implementation of FReT.


    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Haihua [Idaho National Laboratory; Zhang, Hongbin [Idaho National Laboratory; Zou, Ling [Idaho National Laboratory; Martineau, Richard Charles [Idaho National Laboratory


    The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) provides makeup cooling water to the reactor pressure vessel (RPV) when the main steam lines are isolated and the normal supply of water to the reactor vessel is lost. The RCIC system operates independently of AC power, service air, or external cooling water systems. The only required external energy source is from the battery to maintain the logic circuits to control the opening and/or closure of valves in the RCIC systems in order to control the RPV water level by shutting down the RCIC pump to avoid overfilling the RPV and flooding the steam line to the RCIC turbine. It is generally considered in almost all the existing station black-out accidents (SBO) analyses that loss of the DC power would result in overfilling the steam line and allowing liquid water to flow into the RCIC turbine, where it is assumed that the turbine would then be disabled. This behavior, however, was not observed in the Fukushima Daiichi accidents, where the Unit 2 RCIC functioned without DC power for nearly three days. Therefore, more detailed mechanistic models for RCIC system components are needed to understand the extended SBO for BWRs. As part of the effort to develop the next generation reactor system safety analysis code RELAP-7, we have developed a strongly coupled RCIC system model, which consists of a turbine model, a pump model, a check valve model, a wet well model, and their coupling models. Unlike the traditional SBO simulations where mass flow rates are typically given in the input file through time dependent functions, the real mass flow rates through the turbine and the pump loops in our model are dynamically calculated according to conservation laws and turbine/pump operation curves. A simplified SBO demonstration RELAP-7 model with this RCIC model has been successfully developed. The demonstration model includes the major components for the primary system of a BWR, as well as the safety

  7. Establishing a Numerical Modeling Framework for Hydrologic Engineering Analyses of Extreme Storm Events

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaodong; Hossain, Faisal; Leung, L. Ruby


    In this study a numerical modeling framework for simulating extreme storm events was established using the Weather Research and Forecasting (WRF) model. Such a framework is necessary for the derivation of engineering parameters such as probable maximum precipitation that are the cornerstone of large water management infrastructure design. Here this framework was built based on a heavy storm that occurred in Nashville (USA) in 2010, and verified using two other extreme storms. To achieve the optimal setup, several combinations of model resolutions, initial/boundary conditions (IC/BC), cloud microphysics and cumulus parameterization schemes were evaluated using multiple metrics of precipitation characteristics. The evaluation suggests that WRF is most sensitive to IC/BC option. Simulation generally benefits from finer resolutions up to 5 km. At the 15km level, NCEP2 IC/BC produces better results, while NAM IC/BC performs best at the 5km level. Recommended model configuration from this study is: NAM or NCEP2 IC/BC (depending on data availability), 15km or 15km-5km nested grids, Morrison microphysics and Kain-Fritsch cumulus schemes. Validation of the optimal framework suggests that these options are good starting choices for modeling extreme events similar to the test cases. This optimal framework is proposed in response to emerging engineering demands of extreme storm events forecasting and analyses for design, operations and risk assessment of large water infrastructures.

  8. Transformation of Baumgarten's aesthetics into a tool for analysing works and for modelling

    DEFF Research Database (Denmark)

    Thomsen, Bente Dahl


      Abstract: Is this the best form, or does it need further work? The aesthetic object does not possess the perfect qualities; but how do I proceed with the form? These are questions that all modellers ask themselves at some point, and with which they can grapple for days - even weeks - before...... the inspiration to deliver the form finally presents itself. This was the outlet for our plan to devise a tool for analysing works and the practical development of forms. The tool is a set of cards with suggestions for investigations that may assist the modeller in identifying the weaknesses of the form......, or convince him-/herself about its strengths. The cards also contain aesthetical reflections that may be of inspiration in the development of the form....

  9. Estimating required information size by quantifying diversity in random-effects model meta-analyses

    DEFF Research Database (Denmark)

    Wetterslev, Jørn; Thorlund, Kristian; Brok, Jesper


    BACKGROUND: There is increasing awareness that meta-analyses require a sufficiently large information size to detect or reject an anticipated intervention effect. The required information size in a meta-analysis may be calculated from an anticipated a priori intervention effect or from...... an intervention effect suggested by trials with low-risk of bias. METHODS: Information size calculations need to consider the total model variance in a meta-analysis to control type I and type II errors. Here, we derive an adjusting factor for the required information size under any random-effects model meta......-trial variability and a sampling error estimate considering the required information size. D2 is different from the intuitively obvious adjusting factor based on the common quantification of heterogeneity, the inconsistency (I2), which may underestimate the required information size. Thus, D2 and I2 are compared...

  10. Using meta-regression analyses in addition to conventional systematic review methods to examine the variation in cost-effectiveness results : A case study

    NARCIS (Netherlands)

    L.T. Burgers (Laura); F.T. van de Wetering (Fleur); J.L. Severens (Hans); W.K. Redekop (Ken)


    textabstractBackground: Systematic reviews of cost-effectiveness analyses summarize results and describe study characteristics. Variability in the study results is often explained qualitatively or based on sensitivity analyses of individual studies. However, variability due to input parameters and

  11. Biosphere Modeling and Analyses in Support of Total System Performance Assessment

    International Nuclear Information System (INIS)

    Tappen, J. J.; Wasiolek, M. A.; Wu, D. W.; Schmitt, J. F.; Smith, A. J.


    The Nuclear Waste Policy Act of 1982 established the obligations of and the relationship between the U.S. Environmental Protection Agency (EPA), the U.S. Nuclear Regulatory Commission (NRC), and the U.S. Department of Energy (DOE) for the management and disposal of high-level radioactive wastes. In 1985, the EPA promulgated regulations that included a definition of performance assessment that did not consider potential dose to a member of the general public. This definition would influence the scope of activities conducted by DOE in support of the total system performance assessment program until 1995. The release of a National Academy of Sciences (NAS) report on the technical basis for a Yucca Mountain-specific standard provided the impetus for the DOE to initiate activities that would consider the attributes of the biosphere, i.e. that portion of the earth where living things, including man, exist and interact with the environment around them. The evolution of NRC and EPA Yucca Mountain-specific regulations, originally proposed in 1999, was critical to the development and integration of biosphere modeling and analyses into the total system performance assessment program. These proposed regulations initially differed in the conceptual representation of the receptor of interest to be considered in assessing performance. The publication in 2001 of final regulations in which the NRC adopted standard will permit the continued improvement and refinement of biosphere modeling and analyses activities in support of assessment activities

  12. Biosphere Modeling and Analyses in Support of Total System Performance Assessment

    International Nuclear Information System (INIS)

    Jeff Tappen; M.A. Wasiolek; D.W. Wu; J.F. Schmitt


    The Nuclear Waste Policy Act of 1982 established the obligations of and the relationship between the U.S. Environmental Protection Agency (EPA), the U.S. Nuclear Regulatory Commission (NRC), and the U.S. Department of Energy (DOE) for the management and disposal of high-level radioactive wastes. In 1985, the EPA promulgated regulations that included a definition of performance assessment that did not consider potential dose to a member of the general public. This definition would influence the scope of activities conducted by DOE in support of the total system performance assessment program until 1995. The release of a National Academy of Sciences (NAS) report on the technical basis for a Yucca Mountain-specific standard provided the impetus for the DOE to initiate activities that would consider the attributes of the biosphere, i.e. that portion of the earth where living things, including man, exist and interact with the environment around them. The evolution of NRC and EPA Yucca Mountain-specific regulations, originally proposed in 1999, was critical to the development and integration of biosphere modeling and analyses into the total system performance assessment program. These proposed regulations initially differed in the conceptual representation of the receptor of interest to be considered in assessing performance. The publication in 2001 of final regulations in which the NRC adopted standard will permit the continued improvement and refinement of biosphere modeling and analyses activities in support of assessment activities

  13. Quantifying the Representation Error of Land Biosphere Models using High Resolution Footprint Analyses and UAS Observations (United States)

    Hanson, C. V.; Schmidt, A.; Law, B. E.; Moore, W.


    The validity of land biosphere model outputs rely on accurate representations of ecosystem processes within the model. Typically, a vegetation or land cover type for a given area (several Km squared or larger resolution), is assumed to have uniform properties. The limited spacial and temporal resolution of models prevents resolving finer scale heterogeneous flux patterns that arise from variations in vegetation. This representation error must be quantified carefully if models are informed through data assimilation in order to assign appropriate weighting of model outputs and measurement data. The representation error is usually only estimated or ignored entirely due to the difficulty in determining reasonable values. UAS based gas sensors allow measurements of atmospheric CO2 concentrations with unprecedented spacial resolution, providing a means of determining the representation error for CO2 fluxes empirically. In this study we use three dimensional CO2 concentration data in combination with high resolution footprint analyses in order to quantify the representation error for modelled CO2 fluxes for typical resolutions of regional land biosphere models. CO2 concentration data were collected using an Atlatl X6A hexa-copter, carrying a highly calibrated closed path infra-red gas analyzer based sampling system with an uncertainty of ≤ ±0.2 ppm CO2. Gas concentration data was mapped in three dimensions using the UAS on-board position data and compared to footprints generated using WRF 3.61. Chad Hanson, Oregon State University, Corvallis, OR Andres Schmidt, Oregon State University, Corvallis, OR Bev Law, Oregon State University, Corvallis, OR

  14. Challenges of Analysing Gene-Environment Interactions in Mouse Models of Schizophrenia

    Directory of Open Access Journals (Sweden)

    Peter L. Oliver


    Full Text Available The modelling of neuropsychiatric disease using the mouse has provided a wealth of information regarding the relationship between specific genetic lesions and behavioural endophenotypes. However, it is becoming increasingly apparent that synergy between genetic and nongenetic factors is a key feature of these disorders that must also be taken into account. With the inherent limitations of retrospective human studies, experiments in mice have begun to tackle this complex association, combining well-established behavioural paradigms and quantitative neuropathology with a range of environmental insults. The conclusions from this work have been varied, due in part to a lack of standardised methodology, although most have illustrated that phenotypes related to disorders such as schizophrenia are consistently modified. Far fewer studies, however, have attempted to generate a “two-hit” model, whereby the consequences of a pathogenic mutation are analysed in combination with environmental manipulation such as prenatal stress. This significant, yet relatively new, approach is beginning to produce valuable new models of neuropsychiatric disease. Focussing on prenatal and perinatal stress models of schizophrenia, this review discusses the current progress in this field, and highlights important issues regarding the interpretation and comparative analysis of such complex behavioural data.

  15. D Recording for 2d Delivering - the Employment of 3d Models for Studies and Analyses - (United States)

    Rizzi, A.; Baratti, G.; Jiménez, B.; Girardi, S.; Remondino, F.


    In the last years, thanks to the advances of surveying sensors and techniques, many heritage sites could be accurately replicated in digital form with very detailed and impressive results. The actual limits are mainly related to hardware capabilities, computation time and low performance of personal computer. Often, the produced models are not visible on a normal computer and the only solution to easily visualized them is offline using rendered videos. This kind of 3D representations is useful for digital conservation, divulgation purposes or virtual tourism where people can visit places otherwise closed for preservation or security reasons. But many more potentialities and possible applications are available using a 3D model. The problem is the ability to handle 3D data as without adequate knowledge this information is reduced to standard 2D data. This article presents some surveying and 3D modeling experiences within the APSAT project ("Ambiente e Paesaggi dei Siti d'Altura Trentini", i.e. Environment and Landscapes of Upland Sites in Trentino). APSAT is a multidisciplinary project funded by the Autonomous Province of Trento (Italy) with the aim documenting, surveying, studying, analysing and preserving mountainous and hill-top heritage sites located in the region. The project focuses on theoretical, methodological and technological aspects of the archaeological investigation of mountain landscape, considered as the product of sequences of settlements, parcelling-outs, communication networks, resources, and symbolic places. The mountain environment preserves better than others the traces of hunting and gathering, breeding, agricultural, metallurgical, symbolic activities characterised by different lengths and environmental impacts, from Prehistory to the Modern Period. Therefore the correct surveying and documentation of this heritage sites and material is very important. Within the project, the 3DOM unit of FBK is delivering all the surveying and 3D material to

  16. Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 3

    International Nuclear Information System (INIS)

    Gwaltney, R.C.; Bolt, S.E.; Corum, J.M.; Bryson, J.W.


    The third in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. The models are idealized thin-shell structures consisting of two circular cylindrical shells that intersect at right angles. There are no transitions, reinforcements, or fillets in the junction region. This series of model tests serves two basic purposes: the experimental data provide design information directly applicable to nozzles in cylindrical vessels; and the idealized models provide test results for use in developing and evaluating theoretical analyses applicable to nozzles in cylindrical vessels and to thin piping tees. The cylinder of model 3 had a 10 in. OD and the nozzle had a 1.29 in. OD, giving a d 0 /D 0 ratio of 0.129. The OD/thickness ratios for the cylinder and the nozzle were 50 and 7.68 respectively. Thirteen separate loading cases were analyzed. In each, one end of the cylinder was rigidly held. In addition to an internal pressure loading, three mutually perpendicular force components and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. The experimental stress distributions for all the loadings were obtained using 158 three-gage strain rosettes located on the inner and outer surfaces. The loading cases were also analyzed theoretically using a finite-element shell analysis developed at the University of California, Berkeley. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good agreement for this model. (U.S.)

  17. Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 4

    International Nuclear Information System (INIS)

    Gwaltney, R.C.; Bolt, S.E.; Bryson, J.W.


    The last in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. The models in the series are idealized thin-shell structures consisting of two circular cylindrical shells that intersect at right angles. There are no transitions, reinforcements, or fillets in the junction region. This series of model tests serves two basic purposes: (1) the experimental data provide design information directly applicable to nozzles in cylindrical vessels, and (2) the idealized models provide test results for use in developing and evaluating theoretical analyses applicable to nozzles in cylindrical vessels and to thin piping tees. The cylinder of model 4 had an outside diameter of 10 in., and the nozzle had an outside diameter of 1.29 in., giving a d 0 /D 0 ratio of 0.129. The OD/thickness ratios were 50 and 20.2 for the cylinder and nozzle respectively. Thirteen separate loading cases were analyzed. For each loading condition one end of the cylinder was rigidly held. In addition to an internal pressure loading, three mutually perpendicular force components and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. The experimental stress distributions for each of the 13 loadings were obtained using 157 three-gage strain rosettes located on the inner and outer surfaces. Each of the 13 loading cases was also analyzed theoretically using a finite-element shell analysis developed at the University of California, Berkeley. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good agreement for this model. (U.S.)

  18. Genetic analyses of partial egg production in Japanese quail using multi-trait random regression models. (United States)

    Karami, K; Zerehdaran, S; Barzanooni, B; Lotfi, E


    1. The aim of the present study was to estimate genetic parameters for average egg weight (EW) and egg number (EN) at different ages in Japanese quail using multi-trait random regression (MTRR) models. 2. A total of 8534 records from 900 quail, hatched between 2014 and 2015, were used in the study. Average weekly egg weights and egg numbers were measured from second until sixth week of egg production. 3. Nine random regression models were compared to identify the best order of the Legendre polynomials (LP). The most optimal model was identified by the Bayesian Information Criterion. A model with second order of LP for fixed effects, second order of LP for additive genetic effects and third order of LP for permanent environmental effects (MTRR23) was found to be the best. 4. According to the MTRR23 model, direct heritability for EW increased from 0.26 in the second week to 0.53 in the sixth week of egg production, whereas the ratio of permanent environment to phenotypic variance decreased from 0.48 to 0.1. Direct heritability for EN was low, whereas the ratio of permanent environment to phenotypic variance decreased from 0.57 to 0.15 during the production period. 5. For each trait, estimated genetic correlations among weeks of egg production were high (from 0.85 to 0.98). Genetic correlations between EW and EN were low and negative for the first two weeks, but they were low and positive for the rest of the egg production period. 6. In conclusion, random regression models can be used effectively for analysing egg production traits in Japanese quail. Response to selection for increased egg weight would be higher at older ages because of its higher heritability and such a breeding program would have no negative genetic impact on egg production.


    Energy Technology Data Exchange (ETDEWEB)



    The Feasibility Study/or the 200-ZP-1 Groundwater Operable Unit (DOE/RL-2007-28) and the Proposed Plan/or Remediation of the 200-ZP-1 Groundwater Operable Unit (DOE/RL-2007-33) describe the use of groundwater pump-and-treat technology for the 200-ZP-1 Groundwater Operable Unit (OU) as part of an expanded groundwater remedy. During fiscal year 2008 (FY08), a groundwater flow and contaminant transport (flow and transport) model was developed to support remedy design decisions at the 200-ZP-1 OU. This model was developed because the size and influence of the proposed 200-ZP-1 groundwater pump-and-treat remedy will have a larger areal extent than the current interim remedy, and modeling is required to provide estimates of influent concentrations and contaminant mass removal rates to support the design of the aboveground treatment train. The 200 West Area Pre-Conceptual Design/or Final Extraction/Injection Well Network: Modeling Analyses (DOE/RL-2008-56) documents the development of the first version of the MODFLOW/MT3DMS model of the Hanford Site's Central Plateau, as well as the initial application of that model to simulate a potential well field for the 200-ZP-1 remedy (considering only the contaminants carbon tetrachloride and technetium-99). This document focuses on the use of the flow and transport model to identify suitable extraction and injection well locations as part of the 200 West Area 200-ZP-1 Pump-and-Treat Remedial Design/Remedial Action Work Plan (DOEIRL-2008-78). Currently, the model has been developed to the extent necessary to provide approximate results and to lay a foundation for the design basis concentrations that are required in support of the remedial design/remediation action (RD/RA) work plan. The discussion in this document includes the following: (1) Assignment of flow and transport parameters for the model; (2) Definition of initial conditions for the transport model for each simulated contaminant of concern (COC) (i.e., carbon

  20. Noise exposure during pregnancy, birth outcomes and fetal development: meta-analyses using quality effects model. (United States)

    Dzhambov, Angel M; Dimitrova, Donka D; Dimitrakova, Elena D


    Many women are exposed daily to high levels of occupational and residential noise, so the effect of noise exposure on pregnancy should be considered because noise affects both the fetus and the mother herself. However, there is a controversy in the literature regarding the adverse effects of occupational and residential noise on pregnant women and their fetuses. The aim of this study was to conduct systematic review of previously analyzed studies, to add additional information omitted in previous reviews and to perform meta-analyses on the effects of noise exposure on pregnancy, birth outcomes and fetal development. Previous reviews and meta-analyses on the topic were consulted. Additionally, a systematic search in MEDLINE, EMBASE and Internet was carried out. Twenty nine studies were included in the meta-analyses. Quality effects meta-analytical model was applied. Women exposed to high noise levels (in most of the studies ≥ 80 dB) during pregnancy are at a significantly higher risk for having small-for-gestational-age newborn (RR = 1.19, 95% CI: 1.03, 1.38), gestational hypertension (RR = 1.27, 95% CI: 1.03, 1.58) and infant with congenital malformations (RR = 1.47, 95% CI: 1.21, 1.79). The effect was not significant for preeclampsia, perinatal death, spontaneous abortion and preterm birth. The results are consistent with previous findings regarding a higher risk for small-for-gestational-age. They also highlight the significance of residential and occupational noise exposure for developing gestational hypertension and especially congenital malformations.

  1. Normalisation genes for expression analyses in the brown alga model Ectocarpus siliculosus

    Directory of Open Access Journals (Sweden)

    Rousvoal Sylvie


    Full Text Available Abstract Background Brown algae are plant multi-cellular organisms occupying most of the world coasts and are essential actors in the constitution of ecological niches at the shoreline. Ectocarpus siliculosus is an emerging model for brown algal research. Its genome has been sequenced, and several tools are being developed to perform analyses at different levels of cell organization, including transcriptomic expression analyses. Several topics, including physiological responses to osmotic stress and to exposure to contaminants and solvents are being studied in order to better understand the adaptive capacity of brown algae to pollution and environmental changes. A series of genes that can be used to normalise expression analyses is required for these studies. Results We monitored the expression of 13 genes under 21 different culture conditions. These included genes encoding proteins and factors involved in protein translation (ribosomal protein 26S, EF1alpha, IF2A, IF4E and protein degradation (ubiquitin, ubiquitin conjugating enzyme or folding (cyclophilin, and proteins involved in both the structure of the cytoskeleton (tubulin alpha, actin, actin-related proteins and its trafficking function (dynein, as well as a protein implicated in carbon metabolism (glucose 6-phosphate dehydrogenase. The stability of their expression level was assessed using the Ct range, and by applying both the geNorm and the Normfinder principles of calculation. Conclusion Comparisons of the data obtained with the three methods of calculation indicated that EF1alpha (EF1a was the best reference gene for normalisation. The normalisation factor should be calculated with at least two genes, alpha tubulin, ubiquitin-conjugating enzyme or actin-related proteins being good partners of EF1a. Our results exclude actin as a good normalisation gene, and, in this, are in agreement with previous studies in other organisms.

  2. Models for regionalizing economic data and their applications within the scope of forensic disaster analyses (United States)

    Schmidt, Hanns-Maximilian; Wiens, rer. pol. Marcus, , Dr.; Schultmann, rer. pol. Frank, Prof. _., Dr.


    The impact of natural hazards on the economic system can be observed in many different regions all over the world. Once the local economic structure is hit by an event direct costs instantly occur. However, the disturbance on a local level (e.g. parts of city or industries along a river bank) might also cause monetary damages in other, indirectly affected sectors. If the impact of an event is strong, these damages are likely to cascade and spread even on an international scale (e.g. the eruption of Eyjafjallajökull and its impact on the automotive sector in Europe). In order to determine these special impacts, one has to gain insights into the directly hit economic structure before being able to calculate these side effects. Especially, regarding the development of a model used for near real-time forensic disaster analyses any simulation needs to be based on data that is rapidly available or easily to be computed. Therefore, we investigated commonly used or recently discussed methodologies for regionalizing economic data. Surprisingly, even for German federal states there is no official input-output data available that can be used, although it might provide detailed figures concerning economic interrelations between different industry sectors. In the case of highly developed countries, such as Germany, we focus on models for regionalizing nationwide input-output table which is usually available at the national statistical offices. However, when it comes to developing countries (e.g. South-East Asia) the data quality and availability is usually much poorer. In this case, other sources need to be found for the proper assessment of regional economic performance. We developed an indicator-based model that can fill this gap because of its flexibility regarding the level of aggregation and the composability of different input parameters. Our poster presentation brings up a literature review and a summary on potential models that seem to be useful for this specific task

  3. Modelling and simulation of complex sociotechnical systems: envisioning and analysing work environments (United States)

    Hettinger, Lawrence J.; Kirlik, Alex; Goh, Yang Miang; Buckle, Peter


    Accurate comprehension and analysis of complex sociotechnical systems is a daunting task. Empirically examining, or simply envisioning the structure and behaviour of such systems challenges traditional analytic and experimental approaches as well as our everyday cognitive capabilities. Computer-based models and simulations afford potentially useful means of accomplishing sociotechnical system design and analysis objectives. From a design perspective, they can provide a basis for a common mental model among stakeholders, thereby facilitating accurate comprehension of factors impacting system performance and potential effects of system modifications. From a research perspective, models and simulations afford the means to study aspects of sociotechnical system design and operation, including the potential impact of modifications to structural and dynamic system properties, in ways not feasible with traditional experimental approaches. This paper describes issues involved in the design and use of such models and simulations and describes a proposed path forward to their development and implementation. Practitioner Summary: The size and complexity of real-world sociotechnical systems can present significant barriers to their design, comprehension and empirical analysis. This article describes the potential advantages of computer-based models and simulations for understanding factors that impact sociotechnical system design and operation, particularly with respect to process and occupational safety. PMID:25761227

  4. Integrated optimization analyses of aerodynamic/stealth characteristics of helicopter rotor based on surrogate model

    Directory of Open Access Journals (Sweden)

    Jiang Xiangwen


    Full Text Available Based on computational fluid dynamics (CFD method, electromagnetic high-frequency method and surrogate model optimization techniques, an integration design method about aerodynamic/stealth has been established for helicopter rotor. The developed integration design method is composed of three modules: integrated grids generation (the moving-embedded grids for CFD solver and the blade grids for radar cross section (RCS solver are generated by solving Poisson equations and folding approach, aerodynamic/stealth solver (the aerodynamic characteristics are simulated by CFD method based upon Navier–Stokes equations and Spalart–Allmaras (S–A turbulence model, and the stealth characteristics are calculated by using a panel edge method combining the method of physical optics (PO, equivalent currents (MEC and quasi-stationary (MQS, and integrated optimization analysis (based upon the surrogate model optimization technique with full factorial design (FFD and radial basis function (RBF, an integrated optimization analyses on aerodynamic/stealth characteristics of rotor are conducted. Firstly, the scattering characteristics of the rotor with different blade-tip swept and twist angles have been carried out, then time–frequency domain grayscale with strong scattering regions of rotor have been given. Meanwhile, the effects of swept-tip and twist angles on the aerodynamic characteristic of rotor have been performed. Furthermore, by choosing suitable object function and constraint condition, the compromised design about swept and twist combinations of rotor with high aerodynamic performances and low scattering characteristics has been given at last.

  5. Analyses of Research Topics in the Field of Informetrics Based on the Method of Topic Modeling

    Directory of Open Access Journals (Sweden)

    Sung-Chien Lin


    Full Text Available In this study, we used the approach of topic modeling to uncover the possible structure of research topics in the field of Informetrics, to explore the distribution of the topics over years, and to compare the core journals. In order to infer the structure of the topics in the field, the data of the papers published in the Journal of Informetricsand Scientometrics during 2007 to 2013 are retrieved from the database of the Web of Science as input of the approach of topic modeling. The results of this study show that when the number of topics was set to 10, the topic model has the smallest perplexity. Although data scopes and analysis methodsare different to previous studies, the generating topics of this study are consistent with those results produced by analyses of experts. Empirical case studies and measurements of bibliometric indicators were concerned important in every year during the whole analytic period, and the field was increasing stability. Both the two core journals broadly paid more attention to all of the topics in the field of Informetrics. The Journal of Informetricsput particular emphasis on construction and applications ofbibliometric indicators and Scientometrics focused on the evaluation and the factors of productivity of countries, institutions, domains, and journals.

  6. Application of a weighted spatial probability model in GIS to analyse landslides in Penang Island, Malaysia

    Directory of Open Access Journals (Sweden)

    Samy Ismail Elmahdy


    Full Text Available In the current study, Penang Island, which is one of the several mountainous areas in Malaysia that is often subjected to landslide hazard, was chosen for further investigation. A multi-criteria Evaluation and the spatial probability weighted approach and model builder was applied to map and analyse landslides in Penang Island. A set of automated algorithms was used to construct new essential geological and morphometric thematic maps from remote sensing data. The maps were ranked using the weighted probability spatial model based on their contribution to the landslide hazard. Results obtained showed that sites at an elevation of 100–300 m, with steep slopes of 10°–37° and slope direction (aspect in the E and SE directions were areas of very high and high probability for the landslide occurrence; the total areas were 21.393 km2 (11.84% and 58.690 km2 (32.48%, respectively. The obtained map was verified by comparing variogram models of the mapped and the occurred landslide locations and showed a strong correlation with the locations of occurred landslides, indicating that the proposed method can successfully predict the unpredictable landslide hazard. The method is time and cost effective and can be used as a reference for geological and geotechnical engineers.

  7. Comparative modeling analyses of Cs-137 fate in the rivers impacted by Chernobyl and Fukushima accidents

    Energy Technology Data Exchange (ETDEWEB)

    Zheleznyak, M.; Kivva, S. [Institute of Environmental Radioactivity, Fukushima University (Japan)


    The consequences of two largest nuclear accidents of the last decades - at Chernobyl Nuclear Power Plant (ChNPP) (1986) and at Fukushima Daiichi NPP (FDNPP) (2011) clearly demonstrated that radioactive contamination of water bodies in vicinity of NPP and on the waterways from it, e.g., river- reservoir water after Chernobyl accident and rivers and coastal marine waters after Fukushima accident, in the both cases have been one of the main sources of the public concerns on the accident consequences. The higher weight of water contamination in public perception of the accidents consequences in comparison with the real fraction of doses via aquatic pathways in comparison with other dose components is a specificity of public perception of environmental contamination. This psychological phenomenon that was confirmed after these accidents provides supplementary arguments that the reliable simulation and prediction of the radionuclide dynamics in water and sediments is important part of the post-accidental radioecological research. The purpose of the research is to use the experience of the modeling activities f conducted for the past more than 25 years within the Chernobyl affected Pripyat River and Dnieper River watershed as also data of the new monitoring studies in Japan of Abukuma River (largest in the region - the watershed area is 5400 km{sup 2}), Kuchibuto River, Uta River, Niita River, Natsui River, Same River, as also of the studies on the specific of the 'water-sediment' {sup 137}Cs exchanges in this area to refine the 1-D model RIVTOX and 2-D model COASTOX for the increasing of the predictive power of the modeling technologies. The results of the modeling studies are applied for more accurate prediction of water/sediment radionuclide contamination of rivers and reservoirs in the Fukushima Prefecture and for the comparative analyses of the efficiency of the of the post -accidental measures to diminish the contamination of the water bodies. Document

  8. Continuous spatial modelling to analyse planning and economic consequences of offshore wind energy

    International Nuclear Information System (INIS)

    Moeller, Bernd


    Offshore wind resources appear abundant, but technological, economic and planning issues significantly reduce the theoretical potential. While massive investments are anticipated and planners and developers are scouting for viable locations and consider risk and impact, few studies simultaneously address potentials and costs together with the consequences of proposed planning in an analytical and continuous manner and for larger areas at once. Consequences may be investments short of efficiency and equity, and failed planning routines. A spatial resource economic model for the Danish offshore waters is presented, used to analyse area constraints, technological risks, priorities for development and opportunity costs of maintaining competing area uses. The SCREAM-offshore wind model (Spatially Continuous Resource Economic Analysis Model) uses raster-based geographical information systems (GIS) and considers numerous geographical factors, technology and cost data as well as planning information. Novel elements are weighted visibility analysis and geographically recorded shipping movements as variable constraints. A number of scenarios have been described, which include restrictions of using offshore areas, as well as alternative uses such as conservation and tourism. The results comprise maps, tables and cost-supply curves for further resource economic assessment and policy analysis. A discussion of parameter variations exposes uncertainties of technology development, environmental protection as well as competing area uses and illustrates how such models might assist in ameliorating public planning, while procuring decision bases for the political process. The method can be adapted to different research questions, and is largely applicable in other parts of the world. - Research Highlights: → A model for the spatially continuous evaluation of offshore wind resources. → Assessment of spatial constraints, costs and resources for each location. → Planning tool for

  9. A systematic review of approaches to modelling lower limb muscle forces during gait: Applicability to clinical gait analyses. (United States)

    Trinler, Ursula; Hollands, Kristen; Jones, Richard; Baker, Richard


    Computational methods to estimate muscle forces during walking are becoming more common in biomechanical research but not yet in clinical gait analysis. This systematic review aims to identify the current state-of-the-art, examine the differences between approaches, and consider applicability of the current approaches in clinical gait analysis. A systematic database search identified studies including estimated muscle force profiles of the lower limb during healthy walking. These were rated for quality and the muscle force profiles digitised for comparison. From 13.449 identified studies, 22 were finally included which used four modelling approaches: static optimisation, enhanced static optimisation, forward dynamics and EMG-driven. These used a range of different musculoskeletal models, muscle-tendon characteristics and cost functions. There is visually broad agreement between and within approaches about when muscles are active throughout the gait cycle. There remain, considerable differences (CV 7%-151%, range of timing of peak forces in gait cycle 1%-31%) in patterns and magnitudes of force between and within modelling approaches. The main source of this variability is not clear. Different musculoskeletal models, experimental protocols, and modelling approaches will clearly have an effect as will the variability of joint kinetics between healthy individuals. Limited validation of modelling approaches, particularly at the level of individual participants, makes it difficult to conclude if any of the approaches give consistently better estimates than others. While muscle force modelling has clear potential to enhance clinical gait analyses future research is needed to improve validation, accuracy and feasibility of implementation in clinical practice. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Development and application of model RAIA uranium on-line analyser

    International Nuclear Information System (INIS)

    Dong Yanwu; Song Yufen; Zhu Yaokun; Cong Peiyuan; Cui Songru


    The working principle, structure, adjustment and application of model RAIA on-line analyser are reported. The performance of this instrument is reliable. For identical sample, the signal fluctuation in continuous monitoring for four months is less than +-1%. According to required measurement range, appropriate length of sample cell is chosen. The precision of measurement process is better than 1% at 100 g/L U. The detection limit is 50 mg/L. The uranium concentration in process stream can be displayed automatically and printed at any time. It presents 4∼20 mA current signal being proportional to the uranium concentration. This makes a long step towards process continuous control and computer management

  11. A model for analysing factors which may influence quality management procedures in higher education

    Directory of Open Access Journals (Sweden)

    Cătălin MAICAN


    Full Text Available In all universities, the Office for Quality Assurance defines the procedure for assessing the performance of the teaching staff, with a view to establishing students’ perception as regards the teachers’ activity from the point of view of the quality of the teaching process, of the relationship with the students and of the assistance provided for learning. The present paper aims at creating a combined model for evaluation, based on Data Mining statistical methods: starting from the findings revealed by the evaluations teachers performed to students, using the cluster analysis and the discriminant analysis, we identified the subjects which produced significant differences between students’ grades, subjects which were subsequently subjected to an evaluation by students. The results of these analyses allowed the formulation of certain measures for enhancing the quality of the evaluation process.

  12. Developing a system dynamics model to analyse environmental problem in construction site (United States)

    Haron, Fatin Fasehah; Hawari, Nurul Nazihah


    This study aims to develop a system dynamics model at a construction site to analyse the impact of environmental problem. Construction sites may cause damages to the environment, and interference in the daily lives of residents. A proper environmental management system must be used to reduce pollution, enhance bio-diversity, conserve water, respect people and their local environment, measure performance and set targets for the environment and sustainability. This study investigates the damaging impact normally occur during the construction stage. Environmental problem will cause costly mistake in project implementation, either because of the environmental damages that are likely to arise during project implementation, or because of modification that may be required subsequently in order to make the action environmentally acceptable. Thus, findings from this study has helped in significantly reducing the damaging impact towards environment, and improve the environmental management system performance at construction site.

  13. Applying the Land Use Portfolio Model with Hazus to analyse risk from natural hazard events (United States)

    Dinitz, Laura B.; Taketa, Richard A.


    This paper describes and demonstrates the integration of two geospatial decision-support systems for natural-hazard risk assessment and management. Hazus is a risk-assessment tool developed by the Federal Emergency Management Agency to identify risks and estimate the severity of risk from natural hazards. The Land Use Portfolio Model (LUPM) is a risk-management tool developed by the U.S. Geological Survey to evaluate plans or actions intended to reduce risk from natural hazards. We analysed three mitigation policies for one earthquake scenario in the San Francisco Bay area to demonstrate the added value of using Hazus and the LUPM together. The demonstration showed that Hazus loss estimates can be input to the LUPM to obtain estimates of losses avoided through mitigation, rates of return on mitigation investment, and measures of uncertainty. Together, they offer a more comprehensive approach to help with decisions for reducing risk from natural hazards.

  14. Testing a dual-systems model of adolescent brain development using resting-state connectivity analyses. (United States)

    van Duijvenvoorde, A C K; Achterberg, M; Braams, B R; Peters, S; Crone, E A


    The current study aimed to test a dual-systems model of adolescent brain development by studying changes in intrinsic functional connectivity within and across networks typically associated with cognitive-control and affective-motivational processes. To this end, resting-state and task-related fMRI data were collected of 269 participants (ages 8-25). Resting-state analyses focused on seeds derived from task-related neural activation in the same participants: the dorsal lateral prefrontal cortex (dlPFC) from a cognitive rule-learning paradigm and the nucleus accumbens (NAcc) from a reward-paradigm. Whole-brain seed-based resting-state analyses showed an age-related increase in dlPFC connectivity with the caudate and thalamus, and an age-related decrease in connectivity with the (pre)motor cortex. nAcc connectivity showed a strengthening of connectivity with the dorsal anterior cingulate cortex (ACC) and subcortical structures such as the hippocampus, and a specific age-related decrease in connectivity with the ventral medial PFC (vmPFC). Behavioral measures from both functional paradigms correlated with resting-state connectivity strength with their respective seed. That is, age-related change in learning performance was mediated by connectivity between the dlPFC and thalamus, and age-related change in winning pleasure was mediated by connectivity between the nAcc and vmPFC. These patterns indicate (i) strengthening of connectivity between regions that support control and learning, (ii) more independent functioning of regions that support motor and control networks, and (iii) more independent functioning of regions that support motivation and valuation networks with age. These results are interpreted vis-à-vis a dual-systems model of adolescent brain development. Copyright © 2015. Published by Elsevier Inc.

  15. Individual-level space-time analyses of emergency department data using generalized additive modeling

    Directory of Open Access Journals (Sweden)

    Vieira Verónica M


    Full Text Available Abstract Background Although daily emergency department (ED data is a source of information that often includes residence, its potential for space-time analyses at the individual level has not been fully explored. We propose that ED data collected for surveillance purposes can also be used to inform spatial and temporal patterns of disease using generalized additive models (GAMs. This paper describes the methods for adapting GAMs so they can be applied to ED data. Methods GAMs are an effective approach for modeling spatial and temporal distributions of point-wise data, producing smoothed surfaces of continuous risk while adjusting for confounders. In addition to disease mapping, the method allows for global and pointwise hypothesis testing and selection of statistically optimum degree of smoothing using standard statistical software. We applied a two-dimensional GAM for location to ED data of overlapping calendar time using a locally-weighted regression smoother. To illustrate our methods, we investigated the association between participants’ address and the risk of gastrointestinal illness in Cape Cod, Massachusetts over time. Results The GAM space-time analyses simultaneously smooth in units of distance and time by using the optimum degree of smoothing to create data frames of overlapping time periods and then spatially analyzing each data frame. When resulting maps are viewed in series, each data frame contributes a movie frame, allowing us to visualize changes in magnitude, geographic size, and location of elevated risk smoothed over space and time. In our example data, we observed an underlying geographic pattern of gastrointestinal illness with risks consistently higher in the eastern part of our study area over time and intermittent variations of increased risk during brief periods. Conclusions Spatial-temporal analysis of emergency department data with GAMs can be used to map underlying disease risk at the individual-level and view

  16. Parameterization and sensitivity analyses of a radiative transfer model for remote sensing plant canopies (United States)

    Hall, Carlton Raden

    A major objective of remote sensing is determination of biochemical and biophysical characteristics of plant canopies utilizing high spectral resolution sensors. Canopy reflectance signatures are dependent on absorption and scattering processes of the leaf, canopy properties, and the ground beneath the canopy. This research investigates, through field and laboratory data collection, and computer model parameterization and simulations, the relationships between leaf optical properties, canopy biophysical features, and the nadir viewed above-canopy reflectance signature. Emphasis is placed on parameterization and application of an existing irradiance radiative transfer model developed for aquatic systems. Data and model analyses provide knowledge on the relative importance of leaves and canopy biophysical features in estimating the diffuse absorption a(lambda,m-1), diffuse backscatter b(lambda,m-1), beam attenuation alpha(lambda,m-1), and beam to diffuse conversion c(lambda,m-1 ) coefficients of the two-flow irradiance model. Data sets include field and laboratory measurements from three plant species, live oak (Quercus virginiana), Brazilian pepper (Schinus terebinthifolius) and grapefruit (Citrus paradisi) sampled on Cape Canaveral Air Force Station and Kennedy Space Center Florida in March and April of 1997. Features measured were depth h (m), projected foliage coverage PFC, leaf area index LAI, and zenith leaf angle. Optical measurements, collected with a Spectron SE 590 high sensitivity narrow bandwidth spectrograph, included above canopy reflectance, internal canopy transmittance and reflectance and bottom reflectance. Leaf samples were returned to laboratory where optical and physical and chemical measurements of leaf thickness, leaf area, leaf moisture and pigment content were made. A new term, the leaf volume correction index LVCI was developed and demonstrated in support of model coefficient parameterization. The LVCI is based on angle adjusted leaf

  17. Examination of a dual-process model predicting riding with drinking drivers. (United States)

    Hultgren, Brittney A; Scaglione, Nichole M; Cleveland, Michael J; Turrisi, Rob


    Nearly 1 in 5 of the fatalities in alcohol-related crashes are passengers. Few studies have utilized theory to examine modifiable psychosocial predictors of individuals' tendencies to be a passenger in a vehicle operated by a driver who has consumed alcohol. This study used a prospective design to test a dual-process model featuring reasoned and reactive psychological influences and psychosocial constructs as predictors of riding with drinking drivers (RWDD) in a sample of individuals aged 18 to 21. College students (N = 508) completed web-based questionnaires assessing RWDD, psychosocial constructs (attitudes, expectancies, and norms), and reasoned and reactive influences (intentions and willingness) at baseline (the middle of the spring semester) and again 1 and 6 months later. Regression was used to analyze reasoned and reactive influences as proximal predictors of RWDD at the 6-month follow-up. Subsequent analyses examined the relationship between the psychosocial constructs as distal predictors of RWDD and the mediation effects of reasoned and reactive influences. Both reasoned and reactive influences predicted RWDD, while only the reactive influence had a significant unique effect. Reactive influences significantly mediated the effects of peer norms, attitudes, and drinking influences on RWDD. Nearly all effects were constant across gender except parental norms (significant for females). Findings highlight that the important precursors of RWDD were reactive influences, attitudes, and peer and parent norms. These findings suggest several intervention methods, specifically normative feedback interventions, parent-based interventions, and brief motivational interviewing, may be particularly beneficial in reducing RWDD. Copyright © 2015 by the Research Society on Alcoholism.

  18. Nonlinear Modeling and Dynamic Simulation Using Bifurcation and Stability Analyses of Regenerative Chatter of Ball-End Milling Process

    Directory of Open Access Journals (Sweden)

    Jeehyun Jung


    Full Text Available A dynamic model for a ball-end milling process that includes the consideration of cutting force nonlinearities and regenerative chatter effects is presented. The nonlinear cutting force is approximated using a Fourier series and then expanded into a Taylor series up to the third order. A series of nonlinear analyses was performed to investigate the nonlinear dynamic behavior of a ball-end milling system, and the differences between the nonlinear analysis approach and its linear counterpart were examined. A bifurcation analysis of points near the critical equilibrium points was performed using the method of multiple scales (MMS and the method of harmonic balance (MHB to analyse the local chatter behaviors of the system. The bifurcation analysis was conducted at two subcritical Hopf bifurcation points. It was also found that a ball-end milling system with nonlinear cutting forces near its critical equilibrium points is conditionally stable. The analysis and simulation results were compared with experimental data reported in the literature, and the physical significance of the results is discussed.

  19. Online Teacher Professional Development for Gifted Education: Examining the Impact of a New Pedagogical Model (United States)

    Edinger, Matthew J.


    This article theoretically develops and examines the outcomes of a pilot study that evaluates the PACKaGE Model of online Teacher Professional Development (the Model). The Model was created to facilitate positive pedagogical change within gifted education teachers' practice, attitude, collaboration, content knowledge, and goal effectiveness.…

  20. Multivariate genetic analyses of the 2D:4D ratio: examining the effects of hand and measurement technique in data from 757 twin families. (United States)

    Medland, Sarah E; Loehlin, John C


    The ratio of the lengths of the second to fourth digits of the hand (2D:4D) is a sexually dimorphic trait that has been proposed as a measure of prenatal testosterone exposure and a putative correlate of a variety of later behavioral and physiological outcomes including personality, fitness and sexual orientation. We present analyses of 2D:4D ratios collected from twins (1413 individuals) and their nontwin siblings (328 individuals) from 757 families. In this sample 2D:4D was measured from photocopies using digital calipers, and for a subset of participants, computer-aided measurement. Multivariate modeling of the left- and right-hand measurements revealed significant genetic and environmental covariation between hands. The two methods yielded very similar results, and the majority of variance was explained by factors shared by both measurement methods. Neither common environmental nor dominant genetic effects were found, and the covariation between siblings could be accounted for by additive genetic effects accounting for 80% and 71% of the variance for the left and right hands, respectively. There was no evidence of sex differences in the total variance, nor in the magnitude or source of genetic and environmental influences, suggesting that X-linked effects (such as the previously identified association with the Androgen receptor) are likely to be small. However, there were also nonshared environmental effects specific to each hand, which, in addition to measurement error, may in part explain why some studies within in the literature find effects for the 2D:4D ratio of one hand but not the other.

  1. Sensitivity analyses of a colloid-facilitated contaminant transport model for unsaturated heterogeneous soil conditions. (United States)

    Périard, Yann; José Gumiere, Silvio; Rousseau, Alain N.; Caron, Jean


    Certain contaminants may travel faster through soils when they are sorbed to subsurface colloidal particles. Indeed, subsurface colloids may act as carriers of some contaminants accelerating their translocation through the soil into the water table. This phenomenon is known as colloid-facilitated contaminant transport. It plays a significant role in contaminant transport in soils and has been recognized as a source of groundwater contamination. From a mechanistic point of view, the attachment/detachment of the colloidal particles from the soil matrix or from the air-water interface and the straining process may modify the hydraulic properties of the porous media. Šimůnek et al. (2006) developed a model that can simulate the colloid-facilitated contaminant transport in variably saturated porous media. The model is based on the solution of a modified advection-dispersion equation that accounts for several processes, namely: straining, exclusion and attachement/detachement kinetics of colloids through the soil matrix. The solutions of these governing, partial differential equations are obtained using a standard Galerkin-type, linear finite element scheme, implemented in the HYDRUS-2D/3D software (Šimůnek et al., 2012). Modeling colloid transport through the soil and the interaction of colloids with the soil matrix and other contaminants is complex and requires the characterization of many model parameters. In practice, it is very difficult to assess actual transport parameter values, so they are often calibrated. However, before calibration, one needs to know which parameters have the greatest impact on output variables. This kind of information can be obtained through a sensitivity analysis of the model. The main objective of this work is to perform local and global sensitivity analyses of the colloid-facilitated contaminant transport module of HYDRUS. Sensitivity analysis was performed in two steps: (i) we applied a screening method based on Morris' elementary

  2. Modeling and analysing storage systems in agricultural biomass supply chain for cellulosic ethanol production

    International Nuclear Information System (INIS)

    Ebadian, Mahmood; Sowlati, Taraneh; Sokhansanj, Shahab; Townley-Smith, Lawrence; Stumborg, Mark


    Highlights: ► Studied the agricultural biomass supply chain for cellulosic ethanol production. ► Evaluated the impact of storage systems on different supply chain actors. ► Developed a combined simulation/optimization model to evaluate storage systems. ► Compared two satellite storage systems with roadside storage in terms of costs and emitted CO 2 . ► SS would lead to a more cost-efficient supply chain compared to roadside storage. -- Abstract: In this paper, a combined simulation/optimization model is developed to better understand and evaluate the impact of the storage systems on the costs incurred by each actor in the agricultural biomass supply chain including farmers, hauling contractors and the cellulosic ethanol plant. The optimization model prescribes the optimum number and location of farms and storages. It also determines the supply radius, the number of farms required to secure the annual supply of biomass and also the assignment of farms to storage locations. Given the specific design of the supply chain determined by the optimization model, the simulation model determines the number of required machines for each operation, their daily working schedule and utilization rates, along with the capacities of storages. To evaluate the impact of the storage systems on the delivered costs, three storage systems are molded and compared: roadside storage (RS) system and two satellite storage (SS) systems including SS with fixed hauling distance (SF) and SS with variable hauling distance (SV). In all storage systems, it is assumed the loading equipment is dedicated to storage locations. The obtained results from a real case study provide detailed cost figures for each storage system since the developed model analyses the supply chain on an hourly basis and considers time-dependence and stochasticity of the supply chain. Comparison of the storage systems shows SV would outperform SF and RS by reducing the total delivered cost by 8% and 6%, respectively

  3. CERES model application for increasing preparedness to climate variability in agricultural planning—risk analyses (United States)

    Popova, Zornitsa; Kercheva, Milena

    The role of soil, crop, climate and crop management for year-to-year variation of yield and groundwater pollution was quantified by simulation analyses with CERES-maize and CERES-wheat models over a 30-year period for four “soil-crop” combinations. It was established that “Chromic Luvisol-maize-dry land” combination was associated with the greatest coefficient of variability of yields ( Cv = 43%) and drought frequency (in 22 years with yield losses more than 20%) over the analysed period. Average yield losses in dry vegetation seasons were 60% of maize productivity potential under sufficient soil moisture. Traditional and drainage controlling precise irrigation scheduling mitigated drought consequences by reducing year-to-year variability of yield to Cv = 5.6-11.6% on risky Chromic Luvisol. Long-term wheat yields were much more stable ( Cv = 23-26%) than those of maize on Chromic Luvisol. In this case droughts covered 12 of the studied 30 years in which yield losses were 25-30% on the average. Soils of high water holding capacity (as Vertisol) stored 50-150 mm additional precipitation for crop evapotranspiration and thus reduced frequency of drought under both crops to 6-7 cases in 30 years. Agriculture should be more sustainable on this soil since variability of yield dropped to Cv = 13% for wheat and respectively Cv = 21% for maize. As a result Vertisol mitigated yield losses during dry vegetation periods by 10-15% for wheat and 22% for maize if compared with productivity under sufficient soil water. Thirty-year frequency analyses of seasonal nitrogen (N)-leaching, proved that ten of wheat and only one of maize vegetation seasons were susceptible to significant (10-45 kg N/ha/year) ground water pollution on Chromic Luvisol. Simulated precise irrigation scenario did not influence drainage in vegetation period. Another risky situations occurred under maize in the wettest fallow state after extremely dry vegetation (in one more of the studied years) when up

  4. Using species abundance distribution models and diversity indices for biogeographical analyses (United States)

    Fattorini, Simone; Rigal, François; Cardoso, Pedro; Borges, Paulo A. V.


    We examine whether Species Abundance Distribution models (SADs) and diversity indices can describe how species colonization status influences species community assembly on oceanic islands. Our hypothesis is that, because of the lack of source-sink dynamics at the archipelago scale, Single Island Endemics (SIEs), i.e. endemic species restricted to only one island, should be represented by few rare species and consequently have abundance patterns that differ from those of more widespread species. To test our hypothesis, we used arthropod data from the Azorean archipelago (North Atlantic). We divided the species into three colonization categories: SIEs, archipelagic endemics (AZEs, present in at least two islands) and native non-endemics (NATs). For each category, we modelled rank-abundance plots using both the geometric series and the Gambin model, a measure of distributional amplitude. We also calculated Shannon entropy and Buzas and Gibson's evenness. We show that the slopes of the regression lines modelling SADs were significantly higher for SIEs, which indicates a relative predominance of a few highly abundant species and a lack of rare species, which also depresses diversity indices. This may be a consequence of two factors: (i) some forest specialist SIEs may be at advantage over other, less adapted species; (ii) the entire populations of SIEs are by definition concentrated on a single island, without possibility for inter-island source-sink dynamics; hence all populations must have a minimum number of individuals to survive natural, often unpredictable, fluctuations. These findings are supported by higher values of the α parameter of the Gambin mode for SIEs. In contrast, AZEs and NATs had lower regression slopes, lower α but higher diversity indices, resulting from their widespread distribution over several islands. We conclude that these differences in the SAD models and diversity indices demonstrate that the study of these metrics is useful for

  5. Neural Spike-Train Analyses of the Speech-Based Envelope Power Spectrum Model

    Directory of Open Access Journals (Sweden)

    Varsha H. Rallapalli


    Full Text Available Diagnosing and treating hearing impairment is challenging because people with similar degrees of sensorineural hearing loss (SNHL often have different speech-recognition abilities. The speech-based envelope power spectrum model (sEPSM has demonstrated that the signal-to-noise ratio (SNRENV from a modulation filter bank provides a robust speech-intelligibility measure across a wider range of degraded conditions than many long-standing models. In the sEPSM, noise (N is assumed to: (a reduce S + N envelope power by filling in dips within clean speech (S and (b introduce an envelope noise floor from intrinsic fluctuations in the noise itself. While the promise of SNRENV has been demonstrated for normal-hearing listeners, it has not been thoroughly extended to hearing-impaired listeners because of limited physiological knowledge of how SNHL affects speech-in-noise envelope coding relative to noise alone. Here, envelope coding to speech-in-noise stimuli was quantified from auditory-nerve model spike trains using shuffled correlograms, which were analyzed in the modulation-frequency domain to compute modulation-band estimates of neural SNRENV. Preliminary spike-train analyses show strong similarities to the sEPSM, demonstrating feasibility of neural SNRENV computations. Results suggest that individual differences can occur based on differential degrees of outer- and inner-hair-cell dysfunction in listeners currently diagnosed into the single audiological SNHL category. The predicted acoustic-SNR dependence in individual differences suggests that the SNR-dependent rate of susceptibility could be an important metric in diagnosing individual differences. Future measurements of the neural SNRENV in animal studies with various forms of SNHL will provide valuable insight for understanding individual differences in speech-in-noise intelligibility.

  6. Using an operating cost model to analyse the selection of aircraft type on short-haul routes

    CSIR Research Space (South Africa)

    Ssamula, B


    Full Text Available operating cost model to analyse suitable aircraft choices, for short haul routes, in terms of cost-related parameters, for aircraft commonly used within Africa. In this paper all the parameters that are crucial in analysing a transport service are addressed...

  7. Promoting Social Inclusion through Sport for Refugee-Background Youth in Australia: Analysing Different Participation Models

    Directory of Open Access Journals (Sweden)

    Karen Block


    Full Text Available Sports participation can confer a range of physical and psychosocial benefits and, for refugee and migrant youth, may even act as a critical mediator for achieving positive settlement and engaging meaningfully in Australian society. This group has low participation rates however, with identified barriers including costs; discrimination and a lack of cultural sensitivity in sporting environments; lack of knowledge of mainstream sports services on the part of refugee-background settlers; inadequate access to transport; culturally determined gender norms; and family attitudes. Organisations in various sectors have devised programs and strategies for addressing these participation barriers. In many cases however, these responses appear to be ad hoc and under-theorised. This article reports findings from a qualitative exploratory study conducted in a range of settings to examine the benefits, challenges and shortcomings associated with different participation models. Interview participants were drawn from non-government organisations, local governments, schools, and sports clubs. Three distinct models of participation were identified, including short term programs for refugee-background children; ongoing programs for refugee-background children and youth; and integration into mainstream clubs. These models are discussed in terms of their relative challenges and benefits and their capacity to promote sustainable engagement and social inclusion for this population group.

  8. Analysing model fit of psychometric process models: An overview, a new test and an application to the diffusion model. (United States)

    Ranger, Jochen; Kuhn, Jörg-Tobias; Szardenings, Carsten


    Cognitive psychometric models embed cognitive process models into a latent trait framework in order to allow for individual differences. Due to their close relationship to the response process the models allow for profound conclusions about the test takers. However, before such a model can be used its fit has to be checked carefully. In this manuscript we give an overview over existing tests of model fit and show their relation to the generalized moment test of Newey (Econometrica, 53, 1985, 1047) and Tauchen (J. Econometrics, 30, 1985, 415). We also present a new test, the Hausman test of misspecification (Hausman, Econometrica, 46, 1978, 1251). The Hausman test consists of a comparison of two estimates of the same item parameters which should be similar if the model holds. The performance of the Hausman test is evaluated in a simulation study. In this study we illustrate its application to two popular models in cognitive psychometrics, the Q-diffusion model and the D-diffusion model (van der Maas, Molenaar, Maris, Kievit, & Boorsboom, Psychol Rev., 118, 2011, 339; Molenaar, Tuerlinckx, & van der Maas, J. Stat. Softw., 66, 2015, 1). We also compare the performance of the test to four alternative tests of model fit, namely the M 2 test (Molenaar et al., J. Stat. Softw., 66, 2015, 1), the moment test (Ranger et al., Br. J. Math. Stat. Psychol., 2016) and the test for binned time (Ranger & Kuhn, Psychol. Test. Asess. , 56, 2014b, 370). The simulation study indicates that the Hausman test is superior to the latter tests. The test closely adheres to the nominal Type I error rate and has higher power in most simulation conditions. © 2017 The British Psychological Society.

  9. An Examination of Information Technology Valuation Models for the Air Force

    National Research Council Canada - National Science Library

    Peachey, Todd


    .... This thesis is designed to examine models that are currently being used in the public and private sector of the economy to evaluate Information Technology investments to learn which ones might serve...

  10. Molecular approaches for viable bacterial population and transcriptional analyses in a rodent model of dental caries (United States)

    Klein, Marlise I.; Scott-Anne, Kathleen M.; Gregoire, Stacy; Rosalen, Pedro L.; Koo, Hyun


    SUMMARY Culturing methods are the primary approach for microbiological analysis of plaque-biofilms in rodent models of dental caries. In this study, we developed strategies for isolation of DNA and RNA from in vivo formed plaque-biofilms to analyze the viable bacterial population and gene expression. Plaque-biofilm samples from rats were treated with propidium monoazide to isolate DNA from viable cells, and the purified DNA was used to quantify total bacteria and S. mutans population via qPCR and specific primers; the same samples were also analyzed by colony forming unit (CFU) counting. In parallel, RNA was isolated from plaque-biofilm samples (from same animals) and used for transcriptional analyses via RT-qPCR. The viable population of both S. mutans and total bacteria assessed by qPCR were positively correlated with the CFU data (P0.8). However, the qPCR data showed higher bacterial cell counts, particularly for total bacteria (vs. CFU). Moreover, S. mutans proportion in the plaque-biofilm determined by qPCR analysis showed strong correlation with incidence of smooth-surface caries (P=0.0022, r=0.71). The purified RNAs presented high RNA integrity numbers (>7), which allowed measurement of the expression of genes that are critical for S. mutans virulence (e.g. gtfB and gtfC). Our data show that the viable microbial population and the gene expression can be analyzed simultaneously, providing a global assessment of the infectious aspect of the disease dental caries. Our approach could enhance the value of the current rodent model in further understanding the pathophysiology of this disease and facilitating the exploration of novel anti-caries therapies. PMID:22958384

  11. Comparing Multidimensional and Continuum Models of Vocabulary Acquisition: An Empirical Examination of the Vocabulary Knowledge Scale (United States)

    Stewart, Jeffrey; Batty, Aaron Olaf; Bovee, Nicholas


    Second language vocabulary acquisition has been modeled both as multidimensional in nature and as a continuum wherein the learner's knowledge of a word develops along a cline from recognition through production. In order to empirically examine and compare these models, the authors assess the degree to which the Vocabulary Knowledge Scale (VKS;…

  12. Measuring and Examining General Self-Efficacy among Community College Students: A Structural Equation Modeling Approach (United States)

    Chen, Yu; Starobin, Soko S.


    This study examined a psychosocial mechanism of how general self-efficacy interacts with other key factors and influences degree aspiration for students enrolled in an urban diverse community college. Using general self-efficacy scales, the authors hypothesized the General Self-efficacy model for Community College students (the GSE-CC model). A…

  13. African Immigrants, the "New Model Minority": Examining the Reality in U.S. K-12 Schools (United States)

    Ukpokodu, Omiunota N.


    African immigrants in the U.S. have been headlined as America's "new model minority." The purpose of this paper is to examine if evidence exists to support the claim of African immigrant students' (AIS) educational achievement and excellence (a core indicator of the "model minority" theory) in U.S. k-12 schools. Using a…

  14. Examining IS Curriculum Profiles and the IS 2010 Model Curriculum Guidelines in AACSB-Accredited Schools (United States)

    Mills, Robert J.; Velasquez, Nicole Forsgren; Fadel, Kelly J.; Bell, Corbin C.


    The IS 2010 Model Curriculum Guidelines were developed to provide recommendations for standardized information systems curricula while simultaneously allowing for customization within individual programs. While some studies have examined program adherence to the IS 2010 Model Curriculum Guidelines, a more detailed analysis of IS curriculum…

  15. Modeling ecological drivers in marine viral communities using comparative metagenomics and network analyses. (United States)

    Hurwitz, Bonnie L; Westveld, Anton H; Brum, Jennifer R; Sullivan, Matthew B


    Long-standing questions in marine viral ecology are centered on understanding how viral assemblages change along gradients in space and time. However, investigating these fundamental ecological questions has been challenging due to incomplete representation of naturally occurring viral diversity in single gene- or morphology-based studies and an inability to identify up to 90% of reads in viral metagenomes (viromes). Although protein clustering techniques provide a significant advance by helping organize this unknown metagenomic sequence space, they typically use only ∼75% of the data and rely on assembly methods not yet tuned for naturally occurring sequence variation. Here, we introduce an annotation- and assembly-free strategy for comparative metagenomics that combines shared k-mer and social network analyses (regression modeling). This robust statistical framework enables visualization of complex sample networks and determination of ecological factors driving community structure. Application to 32 viromes from the Pacific Ocean Virome dataset identified clusters of samples broadly delineated by photic zone and revealed that geographic region, depth, and proximity to shore were significant predictors of community structure. Within subsets of this dataset, depth, season, and oxygen concentration were significant drivers of viral community structure at a single open ocean station, whereas variability along onshore-offshore transects was driven by oxygen concentration in an area with an oxygen minimum zone and not depth or proximity to shore, as might be expected. Together these results demonstrate that this highly scalable approach using complete metagenomic network-based comparisons can both test and generate hypotheses for ecological investigation of viral and microbial communities in nature.

  16. Inverse analyses of effective diffusion parameters relevant for a two-phase moisture model of cementitious materials

    DEFF Research Database (Denmark)

    Addassi, Mouadh; Johannesson, Björn; Wadsö, Lars


    Here we present an inverse analyses approach to determining the two-phase moisture transport properties relevant to concrete durability modeling. The purposed moisture transport model was based on a continuum approach with two truly separate equations for the liquid and gas phase being connected...

  17. Usefulness of non-linear input-output models for economic impact analyses in tourism and recreation

    NARCIS (Netherlands)

    Klijs, J.; Peerlings, J.H.M.; Heijman, W.J.M.


    In tourism and recreation management it is still common practice to apply traditional input–output (IO) economic impact models, despite their well-known limitations. In this study the authors analyse the usefulness of applying a non-linear input–output (NLIO) model, in which price-induced input

  18. Experimental and modeling analyses for interactions between graphene oxide and quartz sand. (United States)

    Kang, Jin-Kyu; Park, Jeong-Ann; Yi, In-Geol; Kim, Song-Bae


    The aim of this study was to quantify the interactions between graphene oxide (GO) and quartz sand by conducting experimental and modeling analyses. The results show that both GO and quartz sand were negatively charged in the presence of 0-50 mM NaCl and 5 mM CaCl 2 (GO = -43.10 to -17.60 mV, quartz sand = -40.97 to -8.44 mV). In the Derjaguin-Landau-Verwey-Overbeek (DLVO) energy profiles, the adhesion of GO to quartz sand becomes more favorable with increasing NaCl concentration from 0 to 10 mM because the interaction energy profile was compressed and the primary maximum energy barrier was lowered. At 50 mM NaCl and 5 mM CaCl 2 , the primary maximum energy barrier even disappeared, resulting in highly favorable conditions for GO retention to quartz sand. In the Maxwell model analysis, the probability of GO adhesion to quartz sand (α m ) increased from 2.46 × 10 -4 to 9.98 × 10 -1 at ionic strengths of 0-10 mM NaCl. In the column experiments (column length = 10 cm, inner diameter = 2.5 cm, flow rate = 0.5 mL min -1 ), the mass removal (Mr) of GO in quartz sand increased from 5.4% to 97.8% as the NaCl concentration was increased from 0 to 50 mM, indicating that the mobility of GO was high in low ionic strength solutions and decreased with increasing ionic strength. The Mr value of GO at 5 mM CaCl 2 was 100%, demonstrating that Ca 2+ had a much stronger effect than Na + on the mobility of GO. In addition, the mobility of GO was lower than that of chloride (Mr = 1.4%) but far higher than that of multi-walled carbon nanotubes (Mr = 87.0%) in deionized water. In aluminum oxide-coated sand, the Mr value of GO was 98.1% at 0 mM NaCl, revealing that the mobility of GO was reduced in the presence of metal oxides. The transport model analysis indicates that the value of the dimensionless attachment rate coefficient (D a ) increased from 0.11 to 4.47 as the NaCl concentration was increased from 0 to 50 mM. In the colloid filtration model analysis, the

  19. Qualitative and quantitative examination of the performance of regional air quality models representing different modeling approaches

    International Nuclear Information System (INIS)

    Bhumralkar, C.M.; Ludwig, F.L.; Shannon, J.D.; McNaughton, D.


    The calculations of three different air quality models were compared with the best available observations. The comparisons were made without calibrating the models to improve agreement with the observations. Model performance was poor for short averaging times (less than 24 hours). Some of the poor performance can be traced to errors in the input meteorological fields, but error exist on all levels. It should be noted that these models were not originally designed for treating short-term episodes. For short-term episodes, much of the variance in the data can arise from small spatial scale features that tend to be averaged out over longer periods. These small spatial scale features cannot be resolved with the coarse grids that are used for the meteorological and emissions inputs. Thus, it is not surprising that the models performed for the longer averaging times. The models compared were RTM-II, ENAMAP-2 and ACID. (17 refs., 5 figs., 4 tabs

  20. A simple beam model to analyse the durability of adhesively bonded tile floorings in presence of shrinkage

    Directory of Open Access Journals (Sweden)

    S. de Miranda


    Full Text Available A simple beam model for the evaluation of tile debonding due to substrate shrinkage is presented. The tile-adhesive-substrate package is modeled as an Euler-Bernoulli beam laying on a two-layer elastic foundation. An effective discrete model for inter-tile grouting is introduced with the aim of modelling workmanship defects due to partial filled groutings. The model is validated using the results of a 2D FE model. Different defect configurations and adhesive typologies are analysed, focusing the attention on the prediction of normal stresses in the adhesive layer under the assumption of Mode I failure of the adhesive.

  1. Interpersonal Style, Stress, and Depression: An Examination of Transactional and Diathesis-Stress Models. (United States)

    Eberhart, Nicole K; Hammen, Constance L


    The present study examines a transactional, interpersonal model of depression in which stress generation (Hammen, 1991) in romantic relationships mediates the association between aspects of interpersonal style (i.e., attachment, dependency, and reassurance seeking) and depressive symptoms. It also examines an alternative, diathesis-stress model in which interpersonal style interacts with romantic stressors in predicting depressive symptoms. These models were tested in a sample of college women, both prospectively over a four-week period, as well as on a day-today basis using a daily diary methodology. Overall, there was strong evidence for a transactional, mediation model in which interpersonal style predicted romantic conflict stress, and in turn depressive symptoms. The alternative diathesis-stress model of depression was not supported. These results are interpreted in relation to previous research, and key limitations that should be addressed by future research are discussed.

  2. Examination of Solubility Models for the Determination of Transition Metals within Liquid Alkali Metals

    Directory of Open Access Journals (Sweden)

    Jeremy Isler


    Full Text Available The experimental solubility of transition metals in liquid alkali metal was compared to the modeled solubility calculated using various equations for solubility. These equations were modeled using the enthalpy calculations of the semi-empirical Miedema model and various entropy calculations. The accuracy of the predicted solubility compared to the experimental data is more dependent on which liquid alkali metal is being examined rather than the transition metal solute examined. For liquid lithium the calculated solubility by the model was generally larger than experimental values, while for liquid cesium the modeling solubility was significantly smaller than the experimental values. For liquid sodium, potassium, and rubidium the experimental solubilities were within the range calculated by this study. Few data approached the predicted temperature dependence of solubility and instead most data exhibited a less pronounced temperature dependence.

  3. Environmental regulation impacts on international trade: aggregate and sectoral analyses with a bilateral trade flow model

    NARCIS (Netherlands)

    van Beers, C.; van den Bergh, J.C.J.M.


    An important barrier to the implementation of strict environmental regulations is that they are perceived to negatively affect a country's competitiveness, visible through changes in international trade. Whereas theoretical analyses of trade and the environment indicate that relatively strict

  4. Examining Attitudes of Students Regarding the Sports Education Model and Direct Teaching Model (United States)

    Bilgin, Nevruz; Dalkiran, Oguzhan


    The aim of the research was to investigate the effects of sports education model and direct teaching model on the attitudes of the students, and the differences among the attitudes of students. The study group of the research included 29 students from 6th and 7th grade of a secondary school in the 2015-2016 academic years. The experimental group…

  5. The Trauma Outcome Process Assessment Model: A Structural Equation Model Examination of Adjustment (United States)

    Borja, Susan E.; Callahan, Jennifer L.


    This investigation sought to operationalize a comprehensive theoretical model, the Trauma Outcome Process Assessment, and test it empirically with structural equation modeling. The Trauma Outcome Process Assessment reflects a robust body of research and incorporates known ecological factors (e.g., family dynamics, social support) to explain…

  6. Examining the associations between HIV-related stigma and health outcomes in people living with HIV/AIDS: a series of meta-analyses (United States)

    Mitra, Sanjana; Chen, Shiyi; Gogolishvili, David; Globerman, Jason; Chambers, Lori; Wilson, Mike; Logie, Carmen H; Shi, Qiyun; Morassaei, Sara; Rourke, Sean B


    Objective To conduct a systematic review and series of meta-analyses on the association between HIV-related stigma and health among people living with HIV. Data sources A structured search was conducted on 6 electronic databases for journal articles reporting associations between HIV-related stigma and health-related outcomes published between 1996 and 2013. Study eligibility criteria Controlled studies, cohort studies, case-control studies and cross-sectional studies in people living with HIV were considered for inclusion. Outcome measures Mental health (depressive symptoms, emotional and mental distress, anxiety), quality of life, physical health, social support, adherence to antiretroviral therapy, access to and usage of health/social services and risk behaviours. Results 64 studies were included in our meta-analyses. We found significant associations between HIV-related stigma and higher rates of depression, lower social support and lower levels of adherence to antiretroviral medications and access to and usage of health and social services. Weaker relationships were observed between HIV-related stigma and anxiety, quality of life, physical health, emotional and mental distress and sexual risk practices. While risk of bias assessments revealed overall good quality related to how HIV stigma and health outcomes were measured on the included studies, high risk of bias among individual studies was observed in terms of appropriate control for potential confounders. Additional research should focus on elucidating the mechanisms behind the negative relationship between stigma and health to better inform interventions to reduce the impact of stigma on the health and well-being of people with HIV. Conclusions This systematic review and series of meta-analyses support the notion that HIV-related stigma has a detrimental impact on a variety of health-related outcomes in people with HIV. This review can inform the development of multifaceted, intersectoral interventions to

  7. A cohort study using pulmonary function tests and x-ray examination in toner-handling workers: cross-sectional and longitudinal analyses from 2003 to 2008. (United States)

    Kitamura, H; Terunuma, N; Kurosaki, S; Hata, K; Masuda, M; Kochi, T; Yanagi, N; Murase, T; Ogami, A; Higashi, T


    This study uses pulmonary function tests and chest x-ray examinations to examine the relationship between toner-handling work and its health effects. The subjects were 1504 male workers in a Japanese toner and photocopier manufacturing company, in the age range from 19 to 50 years in 2003. Personal exposure measurements, pulmonary function tests, chest x-ray examinations, biomarker measurements, and a questionnaire about respiratory symptoms were conducted. The present study reports the results of pulmonary function tests and chest x-ray examinations conducted in the subjects, which includes a cross-sectional study on the toner handling and non-handling workers and a longitudinal study from 2003 to 2008. Few significant findings were suspected to be caused by toner exposure found in pulmonary function indices in both the cross-sectional and longitudinal studies. Any obvious fibrotic findings in chest x-ray findings related to the toner exposure could not be found out. No evidence of adverse effects on pulmonary function indices and chest x-rays was present in the toner-handling workers as compared to the nonspecifically exposed workers. Although the toner exposure concentration is quite low in the current well-controlled working environment, even among the toner-handling workers, we would like to continue this study in the future to verify the toner exposure health effects. © The Author(s) 2014.

  8. Examination of atmospheric dynamic model's performance over complex terrain under temporally changing synoptic meteorological conditions

    International Nuclear Information System (INIS)

    Nagai, Haruyasu; Yamazawa, Hiromi


    The mesoscale atmospheric dynamic model, a submodel of the numerical atmospheric dispersion model named PHYSIC, was improved and its performance was examined in a coastal area with a complex terrain. To introduce temporally changing synoptic meteorological conditions into the model, the initial and boundary conditions were improved. Moreover, land surface temperature calculations were modified to apply the model to snow-covered areas. These improvements worked effectively in the model simulation of four series of the observations during winter and summer in 1992. The model successfully simulated the wind fields and its temporal variations under the condition of strong westerlies and a land and sea breeze. Limitation of model's performance caused by the temporal and spatial resolutions of input data was also discussed. (author)

  9. Analysis of the variation in local reference dose levels from computed tomography examinations; Analyse av variasjon i representative doser ved computertomografi undersoekelser

    Energy Technology Data Exchange (ETDEWEB)

    Silkoset, R.D.


    Background: Radiation doses from CT examinations vary much between different hospitals and Xray institutes, and the increased numbers of examinations are the reason for the increase in collective effective dose. The aim with the work is to see if this dose variation can be explained by the way the examinations are done and if the is a connection between the dose and work with optimization. Further the aim is to see which signification variations have for the collective effective dose. Material and Methods: Local diagnostic reference level (local DRL) from CT-caput and CT abdomen from 22 hospitals and X-ray institutes in Norway are used and quality assured. A questionnaire gathered data about scan-techniques and doses and various aspects with optimization. Effective dose was estimated for all examinations. Descriptive frequency, correlation and variance analysis were undertaken. Results: The local DRL vary with a factor 3 to 4 for caput and abdomen. Calculated average effective dose shows a small reduction for abdomen compared with an earlier study in Norway (1995). The study shows a reduction in local DRL in 20% for those who frequently revise their protocols and where the radiograph has postgraduate studies in CT and work in a multidisciplinary (medical physicist, radiograph and radiologist) with optimization. Conclusion: CT laboratories emphasis different the optimization work and a large variation in the use of scan-parameters can be found. This results in variation of doses with CT-caput and CT-abdomen examinations. The work interprets that the dose contribution from CT to collective effective dose can be reduced by 50% by working with optimization of protocols. The work forms basis for additional research in the use of dose modulation and scan-techniques. (Author)

  10. Examining the associations between HIV-related stigma and health outcomes in people living with HIV/AIDS: a series of meta-analyses. (United States)

    Rueda, Sergio; Mitra, Sanjana; Chen, Shiyi; Gogolishvili, David; Globerman, Jason; Chambers, Lori; Wilson, Mike; Logie, Carmen H; Shi, Qiyun; Morassaei, Sara; Rourke, Sean B


    To conduct a systematic review and series of meta-analyses on the association between HIV-related stigma and health among people living with HIV. A structured search was conducted on 6 electronic databases for journal articles reporting associations between HIV-related stigma and health-related outcomes published between 1996 and 2013. Controlled studies, cohort studies, case-control studies and cross-sectional studies in people living with HIV were considered for inclusion. Mental health (depressive symptoms, emotional and mental distress, anxiety), quality of life, physical health, social support, adherence to antiretroviral therapy, access to and usage of health/social services and risk behaviours. 64 studies were included in our meta-analyses. We found significant associations between HIV-related stigma and higher rates of depression, lower social support and lower levels of adherence to antiretroviral medications and access to and usage of health and social services. Weaker relationships were observed between HIV-related stigma and anxiety, quality of life, physical health, emotional and mental distress and sexual risk practices. While risk of bias assessments revealed overall good quality related to how HIV stigma and health outcomes were measured on the included studies, high risk of bias among individual studies was observed in terms of appropriate control for potential confounders. Additional research should focus on elucidating the mechanisms behind the negative relationship between stigma and health to better inform interventions to reduce the impact of stigma on the health and well-being of people with HIV. This systematic review and series of meta-analyses support the notion that HIV-related stigma has a detrimental impact on a variety of health-related outcomes in people with HIV. This review can inform the development of multifaceted, intersectoral interventions to reduce the impact of HIV-related stigma on the health and well-being of people living

  11. A Conceptual Model for Analysing Management Development in the UK Hospitality Industry (United States)

    Watson, Sandra


    This paper presents a conceptual, contingent model of management development. It explains the nature of the UK hospitality industry and its potential influence on MD practices, prior to exploring dimensions and relationships in the model. The embryonic model is presented as a model that can enhance our understanding of the complexities of the…

  12. Educational productivity in higher education : An examination of part of the Walberg Educational Productivity Model

    NARCIS (Netherlands)

    Bruinsma, M.; Jansen, E. P. W. A.

    Several factors in the H. J. Walberg Educational Productivity Model, which assumes that 9 factors affect academic achievement, were examined with a limited sample of 1st-year students in the University of Groningen. Information concerning 8 of these factors - grades, motivation, age, prior

  13. Examining Factors Affecting Science Achievement of Hong Kong in PISA 2006 Using Hierarchical Linear Modeling (United States)

    Lam, Terence Yuk Ping; Lau, Kwok Chi


    This study uses hierarchical linear modeling to examine the influence of a range of factors on the science performances of Hong Kong students in PISA 2006. Hong Kong has been consistently ranked highly in international science assessments, such as Programme for International Student Assessment and Trends in International Mathematics and Science…

  14. A reusable simulation model to evaluate the effects of walk-in for diagnostic examinations

    NARCIS (Netherlands)

    Braaksma, A.; Kortbeek, N.; Smid, K.; Sprengers, M. E. S.


    Enabling patients to walk in for their diagnostic examination without an appointment has considerable potential in terms of quality of care, patient service, and system efficiency. We present a model to evaluate the effect of implementing a combined walk-in and appointment system, offering

  15. Examination of a Group Counseling Model of Career Decision Making with College Students (United States)

    Rowell, P. Clay; Mobley, A. Keith; Kemer, Gulsah; Giordano, Amanda


    The authors examined the effectiveness of a group career counseling model (Pyle, K. R., 2007) on college students' career decision-making abilities. They used a Solomon 4-group design and found that students who participated in the career counseling groups had significantly greater increases in career decision-making abilities than those who…

  16. Examining a model of dispositional mindfulness, body comparison, and body satisfaction

    NARCIS (Netherlands)

    Dijkstra, Pieternel; Barelds, Dick P. H.

    The present study examined the links between dispositional mindfulness, body comparison, and body satisfaction. It was expected that mindfulness would be associated with less body comparison and more body satisfaction. Two models were tested: one exploring body comparison as a mediator between

  17. College Students Coping with Interpersonal Stress: Examining a Control-Based Model of Coping (United States)

    Coiro, Mary Jo; Bettis, Alexandra H.; Compas, Bruce E.


    Objective: The ways that college students cope with stress, particularly interpersonal stress, may be a critical factor in determining which students are at risk for impairing mental health disorders. Using a control-based model of coping, the present study examined associations between interpersonal stress, coping strategies, and symptoms.…

  18. Using the Kaleidoscope Career Model to Examine Generational Differences in Work Attitudes (United States)

    Sullivan, Sherry E.; Forret, Monica L.; Carraher, Shawn M.; Mainiero, Lisa A.


    Purpose: The purpose of this paper is to examine, utilising the Kaleidoscope Career Model, whether members of the Baby Boom generation and Generation X differ in their needs for authenticity, balance, and challenge. Design/methodology/approach: Survey data were obtained from 982 professionals located across the USA. Correlations, t-tests, and…

  19. An Examination of Preservice Teachers' Capacity to Create Mathematical Modeling Problems for Children (United States)

    Paolucci, Catherine; Wessels, Helena


    This study examined preservice teachers' (PSTs) capacity to create mathematical modeling problems (MMPs) for grades 1 to 3. PSTs created MMPs for their choice of grade level and aligned the mathematical content of their MMPs with the relevant mathematics curriculum. PSTs were given criteria adapted from Galbraith's MMP design principles to guide…

  20. From intermediate to final behavioral endpoints; Modeling cognitions in (cost-)effectiveness analyses in health promotion

    NARCIS (Netherlands)

    Prenger, Hendrikje Cornelia


    Cost-effectiveness analyses (CEAs) are considered an increasingly important tool in health promotion and psychology. In health promotion adequate effectiveness data of innovative interventions are often lacking. In case of many promising interventions the available data are inadequate for CEAs due

  1. Developing an Innovative Customer Relationship Management Model for Better Health Examination Service

    Directory of Open Access Journals (Sweden)

    Lyu JrJung


    Full Text Available People emphasize on their own health and wish to know more about their conditions. Chronic diseases now take up to 50 percent of top 10 causes of death. As a result, the health-care industry has emerged and kept thriving. This work adopts an innovative customer-oriented business model since most clients are proactive and spontaneous in taking the “distinguished” health examination programs. We adopt the soft system dynamics methodology (SSDM to develop and to evaluate the steps of introducing customer relationship management model into a case health examination organization. Quantitative results are also presented for a case physical examination center and to assess the improved efficiency. The case study shows that the procedures developed here could provide a better service.

  2. Developing a Customer Relationship Management Model for Better Health Examination Service

    Directory of Open Access Journals (Sweden)

    Lyu Jr-Jung


    Full Text Available People emphasize on their own health and wish to know more about their conditions. Chronic diseases now take up to 50 percent of top 10 causes of death. As a result, the health-care industry has emerged and kept thriving. This work adopts a customer-oriented business model since most clients are proactive and spontaneous in taking the “distinguished” health examination programs. We adopt the soft system dynamics methodology (SSDM to develop and to evaluate the steps of introducing customer relationship management model into a case health examination organization. Quantitative results are also presented for a case physical examination center and to assess the improved efficiency. The case study shows that the procedures developed here could provide a better service.

  3. Developing computational model-based diagnostics to analyse clinical chemistry data

    NARCIS (Netherlands)

    Schalkwijk, D.B. van; Bochove, K. van; Ommen, B. van; Freidig, A.P.; Someren, E.P. van; Greef, J. van der; Graaf, A.A. de


    This article provides methodological and technical considerations to researchers starting to develop computational model-based diagnostics using clinical chemistry data.These models are of increasing importance, since novel metabolomics and proteomics measuring technologies are able to produce large

  4. Bio-economic farm modelling to analyse agricultural land productivity in Rwanda

    NARCIS (Netherlands)

    Bidogeza, J.C.


    Keywords: Rwanda; farm household typology; sustainable technology adoption; multivariate analysis;
    land degradation; food security; bioeconomic model; crop simulation models; organic fertiliser; inorganic fertiliser; policy incentives

    In Rwanda, land degradation contributes to the

  5. Bio-economic farm modelling to analyse agricultural land productivity in Rwanda

    NARCIS (Netherlands)

    Bidogeza, J.C.


    Keywords: Rwanda; farm household typology; sustainable technology adoption; multivariate analysis;
    land degradation; food security; bioeconomic model; crop simulation models; organic fertiliser; inorganic fertiliser; policy incentives In Rwanda, land degradation contributes to the low and

  6. An integrative process model of leadership: examining loci, mechanisms, and event cycles. (United States)

    Eberly, Marion B; Johnson, Michael D; Hernandez, Morela; Avolio, Bruce J


    Utilizing the locus (source) and mechanism (transmission) of leadership framework (Hernandez, Eberly, Avolio, & Johnson, 2011), we propose and examine the application of an integrative process model of leadership to help determine the psychological interactive processes that constitute leadership. In particular, we identify the various dynamics involved in generating leadership processes by modeling how the loci and mechanisms interact through a series of leadership event cycles. We discuss the major implications of this model for advancing an integrative understanding of what constitutes leadership and its current and future impact on the field of psychological theory, research, and practice. © 2013 APA, all rights reserved.

  7. Pathophysiologic and transcriptomic analyses of viscerotropic yellow fever in a rhesus macaque model. (United States)

    Engelmann, Flora; Josset, Laurence; Girke, Thomas; Park, Byung; Barron, Alex; Dewane, Jesse; Hammarlund, Erika; Lewis, Anne; Axthelm, Michael K; Slifka, Mark K; Messaoudi, Ilhem


    Infection with yellow fever virus (YFV), an explosively replicating flavivirus, results in viral hemorrhagic disease characterized by cardiovascular shock and multi-organ failure. Unvaccinated populations experience 20 to 50% fatality. Few studies have examined the pathophysiological changes that occur in humans during YFV infection due to the sporadic nature and remote locations of outbreaks. Rhesus macaques are highly susceptible to YFV infection, providing a robust animal model to investigate host-pathogen interactions. In this study, we characterized disease progression as well as alterations in immune system homeostasis, cytokine production and gene expression in rhesus macaques infected with the virulent YFV strain DakH1279 (YFV-DakH1279). Following infection, YFV-DakH1279 replicated to high titers resulting in viscerotropic disease with ∼72% mortality. Data presented in this manuscript demonstrate for the first time that lethal YFV infection results in profound lymphopenia that precedes the hallmark changes in liver enzymes and that although tissue damage was noted in liver, kidneys, and lymphoid tissues, viral antigen was only detected in the liver. These observations suggest that additional tissue damage could be due to indirect effects of viral replication. Indeed, circulating levels of several cytokines peaked shortly before euthanasia. Our study also includes the first description of YFV-DakH1279-induced changes in gene expression within peripheral blood mononuclear cells 3 days post-infection prior to any clinical signs. These data show that infection with wild type YFV-DakH1279 or live-attenuated vaccine strain YFV-17D, resulted in 765 and 46 differentially expressed genes (DEGs), respectively. DEGs detected after YFV-17D infection were mostly associated with innate immunity, whereas YFV-DakH1279 infection resulted in dysregulation of genes associated with the development of immune response, ion metabolism, and apoptosis. Therefore, WT-YFV infection

  8. Reference model for measuring and analysing costs – particularly in business informatics


    Milos Maryska


    This paper is devoted to problems of management of cost efficiency of business informatics with Business Intelligence (BI) assistance. It defines basic critical points that must be taken into account during creating models for management of cost efficiency of business informatics. It proposes new model for management of cost efficiency, this model include also definitions of dimensions and indicators for measuring of this cost efficiency. The model takes into account requirements that pose cl...

  9. Quantifying and Analysing Neighbourhood Characteristics Supporting Urban Land-Use Modelling

    DEFF Research Database (Denmark)

    Hansen, Henning Sten


    Land-use modelling and spatial scenarios have gained increased attention as a means to meet the challenge of reducing uncertainty in the spatial planning and decision-making. Several organisations have developed software for land-use modelling. Many of the recent modelling efforts incorporate cel...

  10. Examining human behavior in video games: The development of a computational model to measure aggression. (United States)

    Lamb, Richard; Annetta, Leonard; Hoston, Douglas; Shapiro, Marina; Matthews, Benjamin


    Video games with violent content have raised considerable concern in popular media and within academia. Recently, there has been considerable attention regarding the claim of the relationship between aggression and video game play. The authors of this study propose the use of a new class of tools developed via computational models to allow examination of the question of whether there is a relationship between violent video games and aggression. The purpose of this study is to computationally model and compare the General Aggression Model with the Diathesis Mode of Aggression related to the play of violent content in video games. A secondary purpose is to provide a method of measuring and examining individual aggression arising from video game play. Total participants examined for this study are N = 1065. This study occurs in three phases. Phase 1 is the development and quantification of the profile combination of traits via latent class profile analysis. Phase 2 is the training of the artificial neural network. Phase 3 is the comparison of each model as a computational model with and without the presence of video game violence. Results suggest that a combination of environmental factors and genetic predispositions trigger aggression related to video games.

  11. On groundwater flow modelling in safety analyses of spent fuel disposal. A comparative study with emphasis on boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Jussila, P


    Modelling groundwater flow is an essential part of the safety assessment of spent fuel disposal because moving groundwater makes a physical connection between a geological repository and the biosphere. Some of the common approaches to model groundwater flow in bedrock are equivalent porous continuum (EC), stochastic continuum and various fracture network concepts. The actual flow system is complex and measuring data are limited. Multiple distinct approaches and models, alternative scenarios as well as calibration and sensitivity analyses are used to give confidence on the results of the calculations. The correctness and orders of magnitude of results of such complex research can be assessed by comparing them to the results of simplified and robust approaches. The first part of this study is a survey of the objects, contents and methods of the groundwater flow modelling performed in the safety assessment of the spent fuel disposal in Finland and Sweden. The most apparent difference of the Swedish studies compared to the Finnish ones is the approach of using more different models, which is enabled by the more resources available in Sweden. The results of more comprehensive approaches provided by international co-operation are very useful to give perspective to the results obtained in Finland. In the second part of this study, the influence of boundary conditions on the flow fields of a simple 2D model is examined. The assumptions and simplifications in this approach include e.g. the following: (1) the EC model is used, in which the 2-dimensional domain is considered a continuum of equivalent properties without fractures present, (2) the calculations are done for stationary fields, without sources or sinks present in the domain and with a constant density of the groundwater, (3) the repository is represented by an isotropic plate, the hydraulic conductivity of which is given fictitious values, (4) the hydraulic conductivity of rock is supposed to have an exponential

  12. Phenology in Germany in the 20th century : methods, analyses and models (United States)

    Schaber, Jörg


    locally combined time series increasing the available data for model development. Apart from analyzed protocolling errors, microclimatic site influences, genetic variation and the observers were identified as sources of uncertainty of phenological observational data. It was concluded that 99% of all phenological observations at a certain site will vary within approximately 24 days around the parametric mean. This supports to the proposed 30-day rule to detect outliers. New phenology models that predict local BB from daily temperature time series were developed. These models were based on simple interactions between inhibitory and promotory agents that are assumed to control the developmental status of a plant. Apart from the fact that, in general, the new models fitted and predicted the observations better than classical models, the main modeling results were: - The bias of the classical models, i.e. overestimation of early observations and underestimation of late observations, could be reduced but not completely removed. - The different favored model structures for each species indicated that for the late spring phases photoperiod played a more dominant role than for early spring phases. - Chilling only plays a subordinate role for spring BB compared to temperatures directly preceding BB. Die Länge der Vegetationsperiode (VP) spielt eine zentrale Rolle für die interannuelle Variation der Kohlenstoffspeicherung terrestrischer Ökosysteme. Die Analyse von Beobachtungsdaten hat gezeigt, dass sich die VP in den letzten Jahrzehnten in den nördlichen Breiten verlängert hat. Dieses Phänomen wurde oft im Zusammenhang mit der globalen Erwärmung diskutiert, da die Phänologie von der Temperatur beeinflusst wird. Die Analyse der Pflanzenphänologie in Süddeutschland im 20. Jahrhundert zeigte: - Die starke Verfrühung der Frühjahrsphasen in dem Jahrzehnt vor 1999 war kein singuläres Ereignis im 20. Jahrhundert. Schon in früheren Dekaden gab es ähnliche Trends. Es konnten

  13. Examining the impact of the walking school bus with an agent-based model. (United States)

    Yang, Yong; Diez-Roux, Ana; Evenson, Kelly R; Colabianchi, Natalie


    We used an agent-based model to examine the impact of the walking school bus (WSB) on children's active travel to school. We identified a synergistic effect of the WSB with other intervention components such as an educational campaign designed to improve attitudes toward active travel to school. Results suggest that to maximize active travel to school, children should arrive on time at "bus stops" to allow faster WSB walking speeds. We also illustrate how an agent-based model can be used to identify the location of routes maximizing the effects of the WSB on active travel. Agent-based models can be used to examine plausible effects of the WSB on active travel to school under various conditions and to identify ways of implementing the WSB that maximize its effectiveness.

  14. Stardust Interstellar Preliminary Examination IV: Scanning Transmission X-Ray Microscopy Analyses of Impact Features in the Stardust Interstellar Dust Collector (United States)

    Butterworth, Anna L.; Westphal, Andrew J.; Frank, David R.; Allen, Carlton C.; Bechtel, Hans A.; Sandford, Scott A.; Tsou, Peter; Zolensky, Michael E.


    We report the quantitative characterization by synchrotron soft X-ray spectroscopy of 31 potential impact features in the aerogel capture medium of the Stardust Interstellar Dust Collector. Samples were analyzed in aerogel by acquiring high spatial resolution maps and high energy-resolution spectra of major rock-forming elements Mg, Al, Si, Fe, and others. We developed diagnostic screening tests to reject spacecraft secondary ejecta and terrestrial contaminants from further consideration as interstellar dust candidates. The results support an extraterrestrial origin for three interstellar candidates: I1043,1,30 (Orion) is a 3 pg particle with Mg-spinel, forsterite, and an iron-bearing phase. I1047,1,34 (Hylabrook) is a 4 pg particle comprising an olivine core surrounded by low-density, amorphous Mg-silicate and amorphous Fe, Cr, and Mn phases. I1003,1,40 (Sorok) has the track morphology of a high-speed impact, but contains no detectable residue that is convincingly distinguishable from the background aerogel. Twenty-two samples with an anthropogenic origin were rejected, including four secondary ejecta from impacts on the Stardust spacecraft aft solar panels, nine ejecta from secondary impacts on the Stardust Sample Return Capsule, and nine contaminants lacking evidence of an impact. Other samples in the collection included I1029,1,6, which contained surviving solar system impactor material. Four samples remained ambiguous: I1006,2,18, I1044,2,32, and I1092,2,38 were too dense for analysis, and we did not detect an intact projectile in I1044,3,33. We detected no radiation effects from the synchrotron soft X-ray analyses; however, we recorded the effects of synchrotron hard X-ray radiation on I1043,1,30 and I1047,1,34.

  15. Preliminary examination of food web structure of Nicola Lake (Taim Hydrological System, south Brazil using dual C and N stable isotope analyses

    Directory of Open Access Journals (Sweden)

    Alexandre M. Garcia

    Full Text Available Taim Ecological Reserve is located within the Taim Hydrological System and was created to protect a heterogeneous and productive landscape harboring exceptional biological diversity in southern Brazil. Using stable isotope ratio analyses of carbon (delta13C and nitrogen (delta15N, we provide a preliminary description of the food web structure, including estimates of production sources supporting fish populations and vertical trophic structure, within a representative lake of this system. A total of 21 organisms (5 macrophytes, 3 mollusks and 13 adult fishes representing 16 species were collected for isotope analysis. Fishes had delta13C values ranging from -24.30º/oo to -28.31º/oo , showing concordance with the range of values observed for macrophytes (-25.49 to -27.10º/oo, and suggesting that these plants could be a major carbon source supporting these fishes. delta13C signatures of Corbicula (-30.81º/oo and Pomacea (-24.26º/oo indirectly suggest that phytoplankton and benthic algae could be alternative carbon sources for some consumers. Nitrogen isotope ratios indicated approximately three consumer trophic levels. The pearl cichlid Geophagus brasiliensis was a primary consumer. Two catfishes (Trachelyopterus lucenai and Loricariichthys anus were secondary consumers. Two congeneric pike cichclids (Crenicichla lepidota and C. punctata, a catfish (Pimelodus maculatus and the characids Astyanax fasciatus and Oligosarcus robustus were tertiary consumers. Further studies including additional primary producers and consumers and greater sample numbers should be conducted to provide a more complete and detailed description of food web structure and dynamics within the reserve.

  16. Pathway models for analysing and managing the introduction of alien plant pests—an overview and categorization (United States)

    J.C. Douma; M. Pautasso; R.C. Venette; C. Robinet; L. Hemerik; M.C.M. Mourits; J. Schans; W. van der Werf


    Alien plant pests are introduced into new areas at unprecedented rates through global trade, transport, tourism and travel, threatening biodiversity and agriculture. Increasingly, the movement and introduction of pests is analysed with pathway models to provide risk managers with quantitative estimates of introduction risks and effectiveness of management options....

  17. Economical analyses of build-operate-transfer model in establishing alternative power plants

    International Nuclear Information System (INIS)

    Yumurtaci, Zehra; Erdem, Hasan Hueseyin


    The most widely employed method to meet the increasing electricity demand is building new power plants. The most important issue in building new power plants is to find financial funds. Various models are employed, especially in developing countries, in order to overcome this problem and to find a financial source. One of these models is the build-operate-transfer (BOT) model. In this model, the investor raises all the funds for mandatory expenses and provides financing, builds the plant and, after a certain plant operation period, transfers the plant to the national power organization. In this model, the object is to decrease the burden of power plants on the state budget. The most important issue in the BOT model is the dependence of the unit electricity cost on the transfer period. In this study, the model giving the unit electricity cost depending on the transfer of the plants established according to the BOT model, has been discussed. Unit electricity investment cost and unit electricity cost in relation to transfer period for plant types have been determined. Furthermore, unit electricity cost change depending on load factor, which is one of the parameters affecting annual electricity production, has been determined, and the results have been analyzed. This method can be employed for comparing the production costs of different plants that are planned to be established according to the BOT model, or it can be employed to determine the appropriateness of the BOT model

  18. Discrete Event Simulation Models for CT Examination Queuing in West China Hospital (United States)

    Luo, Li; Tang, Shijun; Shi, Yingkang; Guo, Huili


    In CT examination, the emergency patients (EPs) have highest priorities in the queuing system and thus the general patients (GPs) have to wait for a long time. This leads to a low degree of satisfaction of the whole patients. The aim of this study is to improve the patients' satisfaction by designing new queuing strategies for CT examination. We divide the EPs into urgent type and emergency type and then design two queuing strategies: one is that the urgent patients (UPs) wedge into the GPs' queue with fixed interval (fixed priority model) and the other is that the patients have dynamic priorities for queuing (dynamic priority model). Based on the data from Radiology Information Database (RID) of West China Hospital (WCH), we develop some discrete event simulation models for CT examination according to the designed strategies. We compare the performance of different strategies on the basis of the simulation results. The strategy that patients have dynamic priorities for queuing makes the waiting time of GPs decrease by 13 minutes and the degree of satisfaction increase by 40.6%. We design a more reasonable CT examination queuing strategy to decrease patients' waiting time and increase their satisfaction degrees. PMID:27547237

  19. An examination of the cross-cultural validity of the Identity Capital Model: American and Japanese students compared. (United States)

    Côté, James E; Mizokami, Shinichi; Roberts, Sharon E; Nakama, Reiko


    The Identity Capital Model proposes that forms of personal agency are associated with identity development as part of the transition to adulthood. This model was examined in two cultural contexts, taking into account age and gender, among college and university students aged 18 to 24 (N = 995). Confirmatory Factor Analyses verified cultural, age, and gender invariance of the two key operationalizations of the model. A Structural Equation Model path analysis confirmed that the model applies in both cultures with minor variations-types of personal agency are associated with the formation of adult- and societal-identities as part of the resolution of the identity stage. It was concluded that forms of personal agency providing the most effective ways of dealing with "individualization" (e.g., internal locus of control) are more important in the transition to adulthood among American students, whereas types of personal agency most effective in dealing with "individualistic collectivism" (e.g., ego strength) are more important among Japanese students. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  20. A Shell/3D Modeling Technique for the Analyses of Delaminated Composite Laminates (United States)

    Krueger, Ronald; OBrien, T. Kevin


    A shell/3D modeling technique was developed for which a local three-dimensional solid finite element model is used only in the immediate vicinity of the delamination front. The goal was to combine the accuracy of the full three-dimensional solution with the computational efficiency of a plate or shell finite element model. Multi-point constraints provided a kinematically compatible interface between the local three-dimensional model and the global structural model which has been meshed with plate or shell finite elements. Double Cantilever Beam (DCB), End Notched Flexure (ENF), and Single Leg Bending (SLB) specimens were modeled using the shell/3D technique to study the feasibility for pure mode I (DCB), mode II (ENF) and mixed mode I/II (SLB) cases. Mixed mode strain energy release rate distributions were computed across the width of the specimens using the virtual crack closure technique. Specimens with a unidirectional layup and with a multidirectional layup where the delamination is located between two non-zero degree plies were simulated. For a local three-dimensional model, extending to a minimum of about three specimen thicknesses on either side of the delamination front, the results were in good agreement with mixed mode strain energy release rates obtained from computations where the entire specimen had been modeled with solid elements. For large built-up composite structures modeled with plate elements, the shell/3D modeling technique offers a great potential for reducing the model size, since only a relatively small section in the vicinity of the delamination front needs to be modeled with solid elements.

  1. Examining rainfall and cholera dynamics in Haiti using statistical and dynamic modeling approaches. (United States)

    Eisenberg, Marisa C; Kujbida, Gregory; Tuite, Ashleigh R; Fisman, David N; Tien, Joseph H


    Haiti has been in the midst of a cholera epidemic since October 2010. Rainfall is thought to be associated with cholera here, but this relationship has only begun to be quantitatively examined. In this paper, we quantitatively examine the link between rainfall and cholera in Haiti for several different settings (including urban, rural, and displaced person camps) and spatial scales, using a combination of statistical and dynamic models. Statistical analysis of the lagged relationship between rainfall and cholera incidence was conducted using case crossover analysis and distributed lag nonlinear models. Dynamic models consisted of compartmental differential equation models including direct (fast) and indirect (delayed) disease transmission, where indirect transmission was forced by empirical rainfall data. Data sources include cholera case and hospitalization time series from the Haitian Ministry of Public Health, the United Nations Water, Sanitation and Health Cluster, International Organization for Migration, and Hôpital Albert Schweitzer. Rainfall data was obtained from rain gauges from the U.S. Geological Survey and Haiti Regeneration Initiative, and remote sensing rainfall data from the National Aeronautics and Space Administration Tropical Rainfall Measuring Mission. A strong relationship between rainfall and cholera was found for all spatial scales and locations examined. Increased rainfall was significantly correlated with increased cholera incidence 4-7 days later. Forcing the dynamic models with rainfall data resulted in good fits to the cholera case data, and rainfall-based predictions from the dynamic models closely matched observed cholera cases. These models provide a tool for planning and managing the epidemic as it continues. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Application of model bread baking in the examination of arabinoxylan-protein complexes in rye bread. (United States)

    Buksa, Krzysztof


    The changes in molecular mass of arabinoxylan (AX) and protein caused by bread baking process were examined using a model rye bread. Instead of the normal flour, the dough contained starch, water-extractable AX and protein which were isolated from rye wholemeal. From the crumb of selected model breads, starch was removed releasing AX-protein complexes, which were further examined by size exclusion chromatography. On the basis of the research, it was concluded that optimum model mix can be composed of 3-6% AX and 3-6% rye protein isolate at 94-88% of rye starch meaning with the most similar properties to low extraction rye flour. Application of model rye bread allowed to examine the interactions between AX and proteins. Bread baked with a share of AX, rye protein and starch, from which the complexes of the highest molar mass were isolated, was characterized by the strongest structure of the bread crumb. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Comparative study analysing women's childbirth satisfaction and obstetric outcomes across two different models of maternity care (United States)

    Conesa Ferrer, Ma Belén; Canteras Jordana, Manuel; Ballesteros Meseguer, Carmen; Carrillo García, César; Martínez Roche, M Emilia


    Objectives To describe the differences in obstetrical results and women's childbirth satisfaction across 2 different models of maternity care (biomedical model and humanised birth). Setting 2 university hospitals in south-eastern Spain from April to October 2013. Design A correlational descriptive study. Participants A convenience sample of 406 women participated in the study, 204 of the biomedical model and 202 of the humanised model. Results The differences in obstetrical results were (biomedical model/humanised model): onset of labour (spontaneous 66/137, augmentation 70/1, p=0.0005), pain relief (epidural 172/132, no pain relief 9/40, p=0.0005), mode of delivery (normal vaginal 140/165, instrumental 48/23, p=0.004), length of labour (0–4 hours 69/93, >4 hours 133/108, p=0.011), condition of perineum (intact perineum or tear 94/178, episiotomy 100/24, p=0.0005). The total questionnaire score (100) gave a mean (M) of 78.33 and SD of 8.46 in the biomedical model of care and an M of 82.01 and SD of 7.97 in the humanised model of care (p=0.0005). In the analysis of the results per items, statistical differences were found in 8 of the 9 subscales. The highest scores were reached in the humanised model of maternity care. Conclusions The humanised model of maternity care offers better obstetrical outcomes and women's satisfaction scores during the labour, birth and immediate postnatal period than does the biomedical model. PMID:27566632

  4. Evidence to Support the Componential Model of Creativity: Secondary Analyses of Three Studies. (United States)

    Conti, Regina; And Others


    Three studies with overlapping participant populations evaluated Amabile's componential model of creativity, which postulates three major creativity components: (1) skills specific to the task domain, (2) general (cross-domain) creativity-relevant skills, and (3) task motivation. Findings of the three studies support Amabile's model. (DB)

  5. Analysing empowerment-oriented email consultation for parents : development of the Guiding the Empowerment Process model

    NARCIS (Netherlands)

    dr. Christa C.C. Nieuwboer


    Online consultation is increasingly offered by parenting practitioners, but it is not clear if it is feasible to provide empowerment-oriented support in a single session email consultation. Based on the empowerment theory, we developed the Guiding the Empowerment Process model (GEP model) to

  6. A laboratory-calibrated model of coho salmon growth with utility for ecological analyses (United States)

    Manhard, Christopher V.; Som, Nicholas A.; Perry, Russell W.; Plumb, John M.


    We conducted a meta-analysis of laboratory- and hatchery-based growth data to estimate broadly applicable parameters of mass- and temperature-dependent growth of juvenile coho salmon (Oncorhynchus kisutch). Following studies of other salmonid species, we incorporated the Ratkowsky growth model into an allometric model and fit this model to growth observations from eight studies spanning ten different populations. To account for changes in growth patterns with food availability, we reparameterized the Ratkowsky model to scale several of its parameters relative to ration. The resulting model was robust across a wide range of ration allocations and experimental conditions, accounting for 99% of the variation in final body mass. We fit this model to growth data from coho salmon inhabiting tributaries and constructed ponds in the Klamath Basin by estimating habitat-specific indices of food availability. The model produced evidence that constructed ponds provided higher food availability than natural tributaries. Because of their simplicity (only mass and temperature are required as inputs) and robustness, ration-varying Ratkowsky models have utility as an ecological tool for capturing growth in freshwater fish populations.

  7. Solving scheduling problems by untimed model checking. The clinical chemical analyser case study

    NARCIS (Netherlands)

    Margaria, T.; Wijs, Anton J.; Massink, M.; van de Pol, Jan Cornelis; Bortnik, Elena M.


    In this article, we show how scheduling problems can be modelled in untimed process algebra, by using special tick actions. A minimal-cost trace leading to a particular action, is one that minimises the number of tick steps. As a result, we can use any (timed or untimed) model checking tool to find

  8. Transcriptomics and proteomics analyses of the PACAP38 influenced ischemic brain in permanent middle cerebral artery occlusion model mice

    Directory of Open Access Journals (Sweden)

    Hori Motohide


    Full Text Available Abstract Introduction The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP is considered to be a potential therapeutic agent for prevention of cerebral ischemia. Ischemia is a most common cause of death after heart attack and cancer causing major negative social and economic consequences. This study was designed to investigate the effect of PACAP38 injection intracerebroventrically in a mouse model of permanent middle cerebral artery occlusion (PMCAO along with corresponding SHAM control that used 0.9% saline injection. Methods Ischemic and non-ischemic brain tissues were sampled at 6 and 24 hours post-treatment. Following behavioral analyses to confirm whether the ischemia has occurred, we investigated the genome-wide changes in gene and protein expression using DNA microarray chip (4x44K, Agilent and two-dimensional gel electrophoresis (2-DGE coupled with matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS, respectively. Western blotting and immunofluorescent staining were also used to further examine the identified protein factor. Results Our results revealed numerous changes in the transcriptome of ischemic hemisphere (ipsilateral treated with PACAP38 compared to the saline-injected SHAM control hemisphere (contralateral. Previously known (such as the interleukin family and novel (Gabra6, Crtam genes were identified under PACAP influence. In parallel, 2-DGE analysis revealed a highly expressed protein spot in the ischemic hemisphere that was identified as dihydropyrimidinase-related protein 2 (DPYL2. The DPYL2, also known as Crmp2, is a marker for the axonal growth and nerve development. Interestingly, PACAP treatment slightly increased its abundance (by 2-DGE and immunostaining at 6 h but not at 24 h in the ischemic hemisphere, suggesting PACAP activates neuronal defense mechanism early on. Conclusions This study provides a detailed inventory of PACAP influenced gene expressions

  9. Exploring Prospective Secondary Mathematics Teachers' Interpretation of Student Thinking through Analysing Students' Work in Modelling (United States)

    Didis, Makbule Gozde; Erbas, Ayhan Kursat; Cetinkaya, Bulent; Cakiroglu, Erdinc; Alacaci, Cengiz


    Researchers point out the importance of teachers' knowledge of student thinking and the role of examining student work in various contexts to develop a knowledge base regarding students' ways of thinking. This study investigated prospective secondary mathematics teachers' interpretations of students' thinking as manifested in students' work that…

  10. Stochastic Spatio-Temporal Models for Analysing NDVI Distribution of GIMMS NDVI3g Images

    Directory of Open Access Journals (Sweden)

    Ana F. Militino


    Full Text Available The normalized difference vegetation index (NDVI is an important indicator for evaluating vegetation change, monitoring land surface fluxes or predicting crop models. Due to the great availability of images provided by different satellites in recent years, much attention has been devoted to testing trend changes with a time series of NDVI individual pixels. However, the spatial dependence inherent in these data is usually lost unless global scales are analyzed. In this paper, we propose incorporating both the spatial and the temporal dependence among pixels using a stochastic spatio-temporal model for estimating the NDVI distribution thoroughly. The stochastic model is a state-space model that uses meteorological data of the Climatic Research Unit (CRU TS3.10 as auxiliary information. The model will be estimated with the Expectation-Maximization (EM algorithm. The result is a set of smoothed images providing an overall analysis of the NDVI distribution across space and time, where fluctuations generated by atmospheric disturbances, fire events, land-use/cover changes or engineering problems from image capture are treated as random fluctuations. The illustration is carried out with the third generation of NDVI images, termed NDVI3g, of the Global Inventory Modeling and Mapping Studies (GIMMS in continental Spain. This data are taken in bymonthly periods from January 2011 to December 2013, but the model can be applied to many other variables, countries or regions with different resolutions.

  11. On computational modeling of visual saliency: Examining what's right, and what's left. (United States)

    Bruce, Neil D B; Wloka, Calden; Frosst, Nick; Rahman, Shafin; Tsotsos, John K


    In the past decade, a large number of computational models of visual saliency have been proposed. Recently a number of comprehensive benchmark studies have been presented, with the goal of assessing the performance landscape of saliency models under varying conditions. This has been accomplished by considering fixation data, annotated image regions, and stimulus patterns inspired by psychophysics. In this paper, we present a high-level examination of challenges in computational modeling of visual saliency, with a heavy emphasis on human vision and neural computation. This includes careful assessment of different metrics for performance of visual saliency models, and identification of remaining difficulties in assessing model performance. We also consider the importance of a number of issues relevant to all saliency models including scale-space, the impact of border effects, and spatial or central bias. Additionally, we consider the biological plausibility of models in stepping away from exemplar input patterns towards a set of more general theoretical principles consistent with behavioral experiments. As a whole, this presentation establishes important obstacles that remain in visual saliency modeling, in addition to identifying a number of important avenues for further investigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Collapsing Factors in Multitrait-Multimethod Models: Examining Consequences of a Mismatch Between Measurement Design and Model

    Directory of Open Access Journals (Sweden)

    Christian eGeiser


    Full Text Available Models of confirmatory factor analysis (CFA are frequently applied to examine the convergent validity of scores obtained from multiple raters or methods in so-called multitrait-multimethod (MTMM investigations. Many applications of CFA-MTMM and similarly structured models result in solutions in which at least one method (or specific factor shows non-significant loading or variance estimates. Eid et al. (2008 distinguished between MTMM measurement designs with interchangeable (randomly selected versus structurally different (fixed methods and showed that each type of measurement design implies specific CFA-MTMM measurement models. In the current study, we hypothesized that some of the problems that are commonly seen in applications of CFA-MTMM models may be due to a mismatch between the underlying measurement design and fitted models. Using simulations, we found that models with M method factors (where M is the total number of methods and unconstrained loadings led to a higher proportion of solutions in which at least one method factor became empirically unstable when these models were fit to data generated from structurally different methods. The simulations also revealed that commonly used model goodness-of-fit criteria frequently failed to identify incorrectly specified CFA-MTMM models. We discuss implications of these findings for other complex CFA models in which similar issues occur, including nested (bifactor and latent state-trait models.

  13. Factor analyses of the Hospital Anxiety and Depression Scale: a Bayesian structural equation modeling approach. (United States)

    Fong, Ted Chun Tat; Ho, Rainbow Tin Hung


    The latent structure of the Hospital Anxiety and Depression Scale (HADS) has caused inconsistent results in the literature. The HADS is frequently analyzed via maximum likelihood confirmatory factor analysis (ML-CFA). However, the overly restrictive assumption of exact zero cross-loadings and residual correlations in ML-CFA can lead to poor model fits and distorted factor structures. This study applied Bayesian structural equation modeling (BSEM) to evaluate the latent structure of the HADS. Three a priori models, the two-factor, three-factor, and bifactor models, were investigated in a Chinese community sample (N = 312) and clinical sample (N = 198) using ML-CFA and BSEM. BSEM specified approximate zero cross-loadings and residual correlations through the use of zero-mean, small-variance informative priors. The model comparison was based on the Bayesian information criterion (BIC). Using ML-CFA, none of the three models provided an adequate fit for either sample. The BSEM two-factor model with approximate zero cross-loadings and residual correlations fitted both samples well with the lowest BIC of the three models and displayed a simple and parsimonious factor-loading pattern. The study demonstrated that the two-factor structure fitted the HADS well, suggesting its usefulness in assessing the symptoms of anxiety and depression in clinical practice. BSEM is a sophisticated and flexible statistical technique that better reflects substantive theories and locates the source of model misfit. Future use of BSEM is recommended to evaluate the latent structure of other psychological instruments.

  14. Analyses of precooling parameters for a bottom flooding ECCS rewetting velocity model

    International Nuclear Information System (INIS)

    Chun, M.H.


    An extension work of the previous paper on the rewetting velocity model is presented. Application of the rewetting velocity model presented elsewhere requires a priori values of phi. In the absence of phi values, film boiling heat transfer coefficient (hsub(df)) and fog-film length (1) data are needed. To provide these informations, a modified Bromley's correlation is first derived and used to obtain hsub(df) values at higher pressure conditions. In addition, the analysis of the precooling parameters, such as phi and 1 is further extended using much more expensive PWR FLECHT data. Thus, the applicable range of the rewetting velocity model is further expanded in this work. (author)

  15. Model-Based Fault Diagnosis: Performing Root Cause and Impact Analyses in Real Time (United States)

    Figueroa, Jorge F.; Walker, Mark G.; Kapadia, Ravi; Morris, Jonathan


    Generic, object-oriented fault models, built according to causal-directed graph theory, have been integrated into an overall software architecture dedicated to monitoring and predicting the health of mission- critical systems. Processing over the generic fault models is triggered by event detection logic that is defined according to the specific functional requirements of the system and its components. Once triggered, the fault models provide an automated way for performing both upstream root cause analysis (RCA), and for predicting downstream effects or impact analysis. The methodology has been applied to integrated system health management (ISHM) implementations at NASA SSC's Rocket Engine Test Stands (RETS).

  16. Silent game as Model for Examining Student Online Creativity - Preliminary Results from an Experiment

    DEFF Research Database (Denmark)

    Sørensen, Jannick Kirk


    -called “Silent game” (Habraken & Gross, 1988). But where Habraken et al.’s research in design games focussed on how professional architects and designers collaborate, we examine the potential of Silent game as model for researching online creative collaboration among students. This paper presents the results...... of the experiment and a tentative analysis. The aim is to discuss the possibilities in using Silent game as a model for examining and improving online creativity.......The ERASMUS+ project “OnCreate” aims at improving online mediated creative collaboration among students. But what are the differences between collaboration online and in a face-to-face setting in terms of creative processes? Theories on media richness and collaborative creativity can provide...

  17. Examining Systems Change in the Response to Domestic Violence: Innovative Applications of Multilevel Modeling. (United States)

    Javdani, Shabnam; Allen, Nicole E; Todd, Nathan R; Anderson, Carolyn J


    Facilitating systems change in the response to domestic violence has been touted as a central goal in the effort to hold systems accountable and create a coordinated response for survivors. However, examination of systems change and whether particular social change efforts (e.g., coordinating councils) contribute to such change is a notoriously difficult research endeavor due in large part to methodological barriers, including those that stem from nonexperimental designs and complex data that are characterized as nested and measured in proportions. This article describes important methodological challenges and proposes innovative techniques to address these challenges. Specifically, multilevel modeling is applied to examine two key systems markers, including protection order and domestic violence program referral rates over time in one state. For each marker, the methodological approach is highlighted and innovations in employing multilevel modeling are discussed. © The Author(s) 2011.

  18. Assessment of PWR fuel degradation by post-irradiation examinations and modeling in DEGRAD-1 code

    International Nuclear Information System (INIS)

    Castanheira, Myrthes; Lucki, Georgi; Silva, Jose Eduardo Rosa da; Terremoto, Luis A.A.; Silva, Antonio Teixeira e; Teodoro, Celso A.; Damy, Margaret de A.


    On the majority of the cases, the inquiries on primary failures and secondary in PWR fuel rods are based on results of analysis were made use of the non-destructive examination results (coolant activities monitoring, sipping tests, visual examination). The complementary analysis methodology proposed in this work includes a modeling approach to characterization of the physical effects of the individual chemistry mechanisms that constitute the incubation phase of degradation phenomenon after primary failure that are integrated in the reactor operational history under stationary operational regime, and normal power transients. The computational program called DEGRAD-1 was developed based on this modeling approach. The practical outcome of the program is to predict cladding regions susceptible to massive hydriding. The applications presented demonstrate the validity of proposed method and models by actual cases simulation, which (primary and secondary) defects positions were known and formation time was estimated. By using the modeling approach, a relationship between the hydrogen concentration in the gap and the inner cladding oxide thickness has been identified which, when satisfied, will induce massive hydriding. The novelty in this work is the integrated methodology, which supplements the traditional analysis methods (using data from non-destructive techniques) with mathematical models for the hydrogen evolution, oxidation and hydriding that include refined approaches and criteria for PWR fuel, and using the FRAPCON-3 fuel performance code as the basic tool. (author)

  19. Examining the dimensional structure models of secondary traumatic stress based on DSM-5 symptoms. (United States)

    Mordeno, Imelu G; Go, Geraldine P; Yangson-Serondo, April


    Latent factor structure of Secondary Traumatic Stress (STS) has been examined using Diagnostic Statistic Manual-IV (DSM-IV)'s Posttraumatic Stress Disorder (PTSD) nomenclature. With the advent of Diagnostic Statistic Manual-5 (DSM-5), there is an impending need to reexamine STS using DSM-5 symptoms in light of the most updated PTSD models in the literature. The study investigated and determined the best fitted PTSD models using DSM-5 PTSD criteria symptoms. Confirmatory factor analysis (CFA) was conducted to examine model fit using the Secondary Traumatic Stress Scale in 241 registered and practicing Filipino nurses (166 females and 75 males) who worked in the Philippines and gave direct nursing services to patients. Based on multiple fit indices, the results showed the 7-factor hybrid model, comprising of intrusion, avoidance, negative affect, anhedonia, externalizing behavior, anxious arousal, and dysphoric arousal factors has excellent fit to STS. This model asserts that: (1) hyperarousal criterion needs to be divided into anxious and dysphoric arousal factors; (2) symptoms characterizing negative and positive affect need to be separated to two separate factors, and; (3) a new factor would categorize externalized, self-initiated impulse and control-deficit behaviors. Comparison of nested and non-nested models showed Hybrid model to have superior fit over other models. The specificity of the symptom structure of STS based on DSM-5 PTSD criteria suggests having more specific interventions addressing the more elaborate symptom-groupings that would alleviate the condition of nurses exposed to STS on a daily basis. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. A critical examination of the youth foyer model for alleviating homelessness: Strengthening a promising evidence base


    Levin, Iris; Borlagdan, Joseph; Mallett, Shelley; Ben, Jehonathan


    This article assesses the quality of 15 primary studies that examined the effectiveness of youth foyer or foyer-like programs on the lives of young homeless people. The youth foyer model provides an integrated approach to tackling youth homelessness, connecting affordable accommodation to training and employment. In Australia, there is growing support from government for the development and funding of foyer programs. However to date, there has been very limited development and investment in t...

  1. Examining Teacher Outcomes of the School-Wide Positive Behavior Support Model in Norway


    Mari-Anne Sørlie; Terje Ogden; Asgeir Røyrhus Olseth


    Research on teacher outcomes of the School-Wide Positive Behavior Support (SWPBS) model has been scarce. The present study adds to the knowledge base by examining the effects of the Norwegian version of SWPBS (N-PALS) on school staffs’ behavior management practices and on their individual and collective efficacy. Questionnaire data were collected from staff and students (Grades 4-7) at four measurement points across fo...

  2. Statistical Modelling of Synaptic Vesicles Distribution and Analysing their Physical Characteristics

    DEFF Research Database (Denmark)

    Khanmohammadi, Mahdieh

    This Ph.D. thesis deals with mathematical and statistical modeling of synaptic vesicle distribution, shape, orientation and interactions. The first major part of this thesis treats the problem of determining the effect of stress on synaptic vesicle distribution and interactions. Serial section...... transmission electron microscopy is used to acquire images from two experimental groups of rats: 1) rats subjected to a behavioral model of stress and 2) rats subjected to sham stress as the control group. The synaptic vesicle distribution and interactions are modeled by employing a point process approach...... on differences of statistical measures in section and the same measures in between sections. Three-dimensional (3D) datasets are reconstructed by using image registration techniques and estimated thicknesses. We distinguish the effect of stress by estimating the synaptic vesicle densities and modeling...

  3. Wave modelling for the North Indian Ocean using MSMR analysed winds

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; Sudheesh, K.; Rupali, S.P.; Babu, M.T.; Jayakumar, S.; Saran, A.K.; Basu, S.K.; Kumar, R.; Sarkar, A.

    NCMRWF (National Centre for Medium Range Weather Forecast) winds assimilated with MSMR (Multi-channel Scanning Microwave Radiometer) winds are used as input to MIKE21 Offshore Spectral Wave model (OSW) which takes into account wind induced wave...

  4. Reference model for measuring and analysing costs – particularly in business informatics

    Directory of Open Access Journals (Sweden)

    Milos Maryska


    Full Text Available This paper is devoted to problems of management of cost efficiency of business informatics with Business Intelligence (BI assistance. It defines basic critical points that must be taken into account during creating models for management of cost efficiency of business informatics. It proposes new model for management of cost efficiency, this model include also definitions of dimensions and indicators for measuring of this cost efficiency. The model takes into account requirements that pose claim on management of cost efficiency necessitated by accounting and requirements from consultancy with managers of companies. It also takes into account requirement of methodologies for management business informatics and methods and processes for evaluating and measuring business informatics. This methodologies, methods and processes are transformed into procedures that are appropriate for measuring and evaluating business informatics. This model is intended for monitoring of actual situation, evolution cost efficiency of business informatics and it can be used for making decisions about convenience of outsourcing of business informatics. There are presented some examples from presentation level of mentioned model for measuring of cost efficiency of business informatics. This presentation level is in the form of tables and also in the form of dashboards.

  5. Analysing stratified medicine business models and value systems: innovation-regulation interactions. (United States)

    Mittra, James; Tait, Joyce


    Stratified medicine offers both opportunities and challenges to the conventional business models that drive pharmaceutical R&D. Given the increasingly unsustainable blockbuster model of drug development, due in part to maturing product pipelines, alongside increasing demands from regulators, healthcare providers and patients for higher standards of safety, efficacy and cost-effectiveness of new therapies, stratified medicine promises a range of benefits to pharmaceutical and diagnostic firms as well as healthcare providers and patients. However, the transition from 'blockbusters' to what might now be termed 'niche-busters' will require the adoption of new, innovative business models, the identification of different and perhaps novel types of value along the R&D pathway, and a smarter approach to regulation to facilitate innovation in this area. In this paper we apply the Innogen Centre's interdisciplinary ALSIS methodology, which we have developed for the analysis of life science innovation systems in contexts where the value creation process is lengthy, expensive and highly uncertain, to this emerging field of stratified medicine. In doing so, we consider the complex collaboration, timing, coordination and regulatory interactions that shape business models, value chains and value systems relevant to stratified medicine. More specifically, we explore in some depth two convergence models for co-development of a therapy and diagnostic before market authorisation, highlighting the regulatory requirements and policy initiatives within the broader value system environment that have a key role in determining the probable success and sustainability of these models. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Analysing the Costs of Integrated Care: A Case on Model Selection for Chronic Care Purposes

    Directory of Open Access Journals (Sweden)

    Marc Carreras


    Full Text Available Background: The objective of this study is to investigate whether the algorithm proposed by Manning and Mullahy, a consolidated health economics procedure, can also be used to estimate individual costs for different groups of healthcare services in the context of integrated care. Methods: A cross-sectional study focused on the population of the Baix Empordà (Catalonia-Spain for the year 2012 (N = 92,498 individuals. A set of individual cost models as a function of sex, age and morbidity burden were adjusted and individual healthcare costs were calculated using a retrospective full-costing system. The individual morbidity burden was inferred using the Clinical Risk Groups (CRG patient classification system. Results: Depending on the characteristics of the data, and according to the algorithm criteria, the choice of model was a linear model on the log of costs or a generalized linear model with a log link. We checked for goodness of fit, accuracy, linear structure and heteroscedasticity for the models obtained. Conclusion: The proposed algorithm identified a set of suitable cost models for the distinct groups of services integrated care entails. The individual morbidity burden was found to be indispensable when allocating appropriate resources to targeted individuals.

  7. Examining the Support Peer Supporters Provide Using Structural Equation Modeling: Nondirective and Directive Support in Diabetes Management. (United States)

    Kowitt, Sarah D; Ayala, Guadalupe X; Cherrington, Andrea L; Horton, Lucy A; Safford, Monika M; Soto, Sandra; Tang, Tricia S; Fisher, Edwin B


    Little research has examined the characteristics of peer support. Pertinent to such examination may be characteristics such as the distinction between nondirective support (accepting recipients' feelings and cooperative with their plans) and directive (prescribing "correct" choices and feelings). In a peer support program for individuals with diabetes, this study examined (a) whether the distinction between nondirective and directive support was reflected in participants' ratings of support provided by peer supporters and (b) how nondirective and directive support were related to depressive symptoms, diabetes distress, and Hemoglobin A1c (HbA1c). Three hundred fourteen participants with type 2 diabetes provided data on depressive symptoms, diabetes distress, and HbA1c before and after a diabetes management intervention delivered by peer supporters. At post-intervention, participants reported how the support provided by peer supporters was nondirective or directive. Confirmatory factor analysis (CFA), correlation analyses, and structural equation modeling examined the relationships among reports of nondirective and directive support, depressive symptoms, diabetes distress, and measured HbA1c. CFA confirmed the factor structure distinguishing between nondirective and directive support in participants' reports of support delivered by peer supporters. Controlling for demographic factors, baseline clinical values, and site, structural equation models indicated that at post-intervention, participants' reports of nondirective support were significantly associated with lower, while reports of directive support were significantly associated with greater depressive symptoms, altogether (with control variables) accounting for 51% of the variance in depressive symptoms. Peer supporters' nondirective support was associated with lower, but directive support was associated with greater depressive symptoms.

  8. Thermo-mechanical analyses and model validation in the HAW test field. Final report

    International Nuclear Information System (INIS)

    Heijdra, J.J.; Broerse, J.; Prij, J.


    An overview is given of the thermo-mechanical analysis work done for the design of the High Active Waste experiment and for the purpose of validation of the used models through comparison with experiments. A brief treatise is given on the problems of validation of models used for the prediction of physical behaviour which cannot be determined with experiments. The analysis work encompasses investigations into the initial state of stress in the field, the constitutive relations, the temperature rise, and the pressure on the liner tubes inserted in the field to guarantee the retrievability of the radioactive sources used for the experiment. The measurements of temperatures, deformations, and stresses are described and an evaluation is given of the comparison of measured and calculated data. An attempt has been made to qualify or even quantify the discrepancies, if any, between measurements and calculations. It was found that the model for the temperature calculations performed adequately. For the stresses the general tendency was good, however, large discrepancies exist mainly due to inaccuracies in the measurements. For the deformations again the general tendency of the model predictions was in accordance with the measurements. However, from the evaluation it appears that in spite of the efforts to estimate the correct initial rock pressure at the location of the experiment, this pressure has been underestimated. The evaluation has contributed to a considerable increase in confidence in the models and gives no reason to question the constitutive model for rock salt. However, due to the quality of the measurements of the stress and the relatively short period of the experiments no quantitatively firm support for the constitutive model is acquired. Collections of graphs giving the measured and calculated data are attached as appendices. (orig.)

  9. Comprehensive analyses of ventricular myocyte models identify targets exhibiting favorable rate dependence.

    Directory of Open Access Journals (Sweden)

    Megan A Cummins


    Full Text Available Reverse rate dependence is a problematic property of antiarrhythmic drugs that prolong the cardiac action potential (AP. The prolongation caused by reverse rate dependent agents is greater at slow heart rates, resulting in both reduced arrhythmia suppression at fast rates and increased arrhythmia risk at slow rates. The opposite property, forward rate dependence, would theoretically overcome these parallel problems, yet forward rate dependent (FRD antiarrhythmics remain elusive. Moreover, there is evidence that reverse rate dependence is an intrinsic property of perturbations to the AP. We have addressed the possibility of forward rate dependence by performing a comprehensive analysis of 13 ventricular myocyte models. By simulating populations of myocytes with varying properties and analyzing population results statistically, we simultaneously predicted the rate-dependent effects of changes in multiple model parameters. An average of 40 parameters were tested in each model, and effects on AP duration were assessed at slow (0.2 Hz and fast (2 Hz rates. The analysis identified a variety of FRD ionic current perturbations and generated specific predictions regarding their mechanisms. For instance, an increase in L-type calcium current is FRD when this is accompanied by indirect, rate-dependent changes in slow delayed rectifier potassium current. A comparison of predictions across models identified inward rectifier potassium current and the sodium-potassium pump as the two targets most likely to produce FRD AP prolongation. Finally, a statistical analysis of results from the 13 models demonstrated that models displaying minimal rate-dependent changes in AP shape have little capacity for FRD perturbations, whereas models with large shape changes have considerable FRD potential. This can explain differences between species and between ventricular cell types. Overall, this study provides new insights, both specific and general, into the determinants of

  10. Scenario sensitivity analyses performed on the PRESTO-EPA LLW risk assessment models

    International Nuclear Information System (INIS)

    Bandrowski, M.S.


    The US Environmental Protection Agency (EPA) is currently developing standards for the land disposal of low-level radioactive waste. As part of the standard development, EPA has performed risk assessments using the PRESTO-EPA codes. A program of sensitivity analysis was conducted on the PRESTO-EPA codes, consisting of single parameter sensitivity analysis and scenario sensitivity analysis. The results of the single parameter sensitivity analysis were discussed at the 1987 DOE LLW Management Conference. Specific scenario sensitivity analyses have been completed and evaluated. Scenario assumptions that were analyzed include: site location, disposal method, form of waste, waste volume, analysis time horizon, critical radionuclides, use of buffer zones, and global health effects

  11. An examination of the Sport Drug Control Model with elite Australian athletes. (United States)

    Gucciardi, Daniel F; Jalleh, Geoffrey; Donovan, Robert J


    This study presents an opportunistic examination of the theoretical tenets outlined in the Sport Drug Control Model(1) using questionnaire items from a survey of 643 elite Australian athletes. Items in the questionnaire that related to the concepts in the model were identified and structural equation modelling was employed to test the hypothesised model. Morality (cheating), benefit appraisal (performance), and threat appraisal (enforcement) evidenced the strongest relationships with attitude to doping, which in turn was positively associated with doping susceptibility. Self-esteem, perceptions of legitimacy and reference group opinions showed small non-significant associations with attitude to doping. The hypothesised model accounted for 30% and 11% of the variance in attitudes to doping and doping susceptibility, respectively. These present findings provide support for the model even though the questionnaire items were not constructed to specifically measure concepts contained in it. Thus, the model appears useful for understanding influences on doping. Nevertheless, there is a need to further explore individual and social factors that may influence athletes' use of performance enhancing drugs. Copyright © 2011 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  12. Human Atrial Cell Models to Analyse Haemodialysis-Related Effects on Cardiac Electrophysiology: Work in Progress

    Directory of Open Access Journals (Sweden)

    Elisa Passini


    Full Text Available During haemodialysis (HD sessions, patients undergo alterations in the extracellular environment, mostly concerning plasma electrolyte concentrations, pH, and volume, together with a modification of sympathovagal balance. All these changes affect cardiac electrophysiology, possibly leading to an increased arrhythmic risk. Computational modeling may help to investigate the impact of HD-related changes on atrial electrophysiology. However, many different human atrial action potential (AP models are currently available, all validated only with the standard electrolyte concentrations used in experiments. Therefore, they may respond in different ways to the same environmental changes. After an overview on how the computational approach has been used in the past to investigate the effect of HD therapy on cardiac electrophysiology, the aim of this work has been to assess the current state of the art in human atrial AP models, with respect to the HD context. All the published human atrial AP models have been considered and tested for electrolytes, volume changes, and different acetylcholine concentrations. Most of them proved to be reliable for single modifications, but all of them showed some drawbacks. Therefore, there is room for a new human atrial AP model, hopefully able to physiologically reproduce all the HD-related effects. At the moment, work is still in progress in this specific field.

  13. The Computational Fluid Dynamics Analyses on Hemodynamic Characteristics in Stenosed Arterial Models

    Directory of Open Access Journals (Sweden)

    Yue Zhou


    Full Text Available Arterial stenosis plays an important role in the progressions of thrombosis and stroke. In the present study, a standard axisymmetric tube model of the stenotic artery is introduced and the degree of stenosis η is evaluated by the area ratio of the blockage to the normal vessel. A normal case (η=0 and four stenotic cases of η=0.25, 0.5, 0.625, and 0.75 with a constant Reynolds number of 300 are simulated by computational fluid dynamics (CFD, respectively, with the Newtonian and Carreau models for comparison. Results show that for both models, the poststenotic separation vortex length increases exponentially with the growth of stenosis degree. However, the vortex length of the Carreau model is shorter than that of the Newtonian model. The artery narrowing accelerates blood flow, which causes high blood pressure and wall shear stress (WSS. The pressure drop of the η=0.75 case is nearly 8 times that of the normal value, while the WSS peak at the stenosis region of η=0.75 case even reaches up to 15 times that of the normal value. The present conclusions are of generality and contribute to the understanding of the dynamic mechanisms of artery stenosis diseases.

  14. Monte Carlo modeling of Standard Model multi-boson production processes for $\\sqrt{s} = 13$ TeV ATLAS analyses

    CERN Document Server

    Li, Shu; The ATLAS collaboration


    Proceeding for the poster presentation at LHCP2017, Shanghai, China on the topic of "Monte Carlo modeling of Standard Model multi-boson production processes for $\\sqrt{s} = 13$ TeV ATLAS analyses" (ATL-PHYS-SLIDE-2017-265 Deadline: 01/09/2017

  15. Latent Variable Modelling and Item Response Theory Analyses in Marketing Research

    Directory of Open Access Journals (Sweden)

    Brzezińska Justyna


    Full Text Available Item Response Theory (IRT is a modern statistical method using latent variables designed to model the interaction between a subject’s ability and the item level stimuli (difficulty, guessing. Item responses are treated as the outcome (dependent variables, and the examinee’s ability and the items’ characteristics are the latent predictor (independent variables. IRT models the relationship between a respondent’s trait (ability, attitude and the pattern of item responses. Thus, the estimation of individual latent traits can differ even for two individuals with the same total scores. IRT scores can yield additional benefits and this will be discussed in detail. In this paper theory and application with R software with the use of packages designed for modelling IRT will be presented.

  16. Analysing improvements to on-street public transport systems: a mesoscopic model approach

    DEFF Research Database (Denmark)

    Ingvardson, Jesper Bláfoss; Kornerup Jensen, Jonas; Nielsen, Otto Anker


    Light rail transit and bus rapid transit have shown to be efficient and cost-effective in improving public transport systems in cities around the world. As these systems comprise various elements, which can be tailored to any given setting, e.g. pre-board fare-collection, holding strategies...... a mesoscopic model which makes it possible to evaluate public transport operations in details, including dwell times, intelligent traffic signal timings and holding strategies while modelling impacts from other traffic using statistical distributional data thereby ensuring simplicity in use and fast...... and other advanced public transport systems (APTS), the attractiveness of such systems depends heavily on their implementation. In the early planning stage it is advantageous to deploy simple and transparent models to evaluate possible ways of implementation. For this purpose, the present study develops...

  17. Accounting for Heterogeneity in Relative Treatment Effects for Use in Cost-Effectiveness Models and Value-of-Information Analyses. (United States)

    Welton, Nicky J; Soares, Marta O; Palmer, Stephen; Ades, Anthony E; Harrison, David; Shankar-Hari, Manu; Rowan, Kathy M


    Cost-effectiveness analysis (CEA) models are routinely used to inform health care policy. Key model inputs include relative effectiveness of competing treatments, typically informed by meta-analysis. Heterogeneity is ubiquitous in meta-analysis, and random effects models are usually used when there is variability in effects across studies. In the absence of observed treatment effect modifiers, various summaries from the random effects distribution (random effects mean, predictive distribution, random effects distribution, or study-specific estimate [shrunken or independent of other studies]) can be used depending on the relationship between the setting for the decision (population characteristics, treatment definitions, and other contextual factors) and the included studies. If covariates have been measured that could potentially explain the heterogeneity, then these can be included in a meta-regression model. We describe how covariates can be included in a network meta-analysis model and how the output from such an analysis can be used in a CEA model. We outline a model selection procedure to help choose between competing models and stress the importance of clinical input. We illustrate the approach with a health technology assessment of intravenous immunoglobulin for the management of adult patients with severe sepsis in an intensive care setting, which exemplifies how risk of bias information can be incorporated into CEA models. We show that the results of the CEA and value-of-information analyses are sensitive to the model and highlight the importance of sensitivity analyses when conducting CEA in the presence of heterogeneity. The methods presented extend naturally to heterogeneity in other model inputs, such as baseline risk. © The Author(s) 2015.

  18. Features and analyses of W7-X cryostat system FE model

    Energy Technology Data Exchange (ETDEWEB)

    Eeten, Paul van, E-mail:; Bräuer, Torsten; Bykov, Victor; Carls, Andre; Fellinger, Joris; Kallmeyer, J.P.


    The Wendelstein 7-X stellarator is presently under construction at the Max-Planck-Institute for Plasma Physics in Greifswald with the goal to verify that a stellarator magnetic confinement concept is a viable option for a fusion power plant. The main components of the W7-X cryostat system are the plasma vessel (PV), outer vessel (OV), ports, thermal insulation, vessel supports and the machine base (MB). The main task of the cryostat system is to provide an insulating vacuum for the cryogenic magnet system while allowing external access to the PV through ports for diagnostic, supply and heating systems. The cryostat is subjected to different types of loads during assembly, maintenance and operation. This ranges from basic weight loads from all installed components to mechanical, vacuum and thermal loads. To predict the behavior of the cryostat in terms of deformations, stresses and support load distribution a finite element (FE) global model has been created called the Global Model of the Cryostat System (GMCS). A complete refurbishment of the GM CS has been done in the last 2 years to prepare the model for future applications. This involved a complete mesh update of the model, an improvement of many model features, an update of the applied operational loads and boundary conditions as well as the creation of automatic post processing procedures. Currently the GMCS is used to support several significant assembly and commissioning steps of W7-X that involve the cryostat system, e.g. the removal of temporary supports beneath the MB, transfer of the PV from temporary to the final supports and evacuation of the cryostat. In the upcoming months the model will be used for further support of the commissioning of W7-X which includes the first evacuation of the PV.

  19. Features and analyses of W7-X cryostat system FE model

    International Nuclear Information System (INIS)

    Eeten, Paul van; Bräuer, Torsten; Bykov, Victor; Carls, Andre; Fellinger, Joris; Kallmeyer, J.P.


    The Wendelstein 7-X stellarator is presently under construction at the Max-Planck-Institute for Plasma Physics in Greifswald with the goal to verify that a stellarator magnetic confinement concept is a viable option for a fusion power plant. The main components of the W7-X cryostat system are the plasma vessel (PV), outer vessel (OV), ports, thermal insulation, vessel supports and the machine base (MB). The main task of the cryostat system is to provide an insulating vacuum for the cryogenic magnet system while allowing external access to the PV through ports for diagnostic, supply and heating systems. The cryostat is subjected to different types of loads during assembly, maintenance and operation. This ranges from basic weight loads from all installed components to mechanical, vacuum and thermal loads. To predict the behavior of the cryostat in terms of deformations, stresses and support load distribution a finite element (FE) global model has been created called the Global Model of the Cryostat System (GMCS). A complete refurbishment of the GM CS has been done in the last 2 years to prepare the model for future applications. This involved a complete mesh update of the model, an improvement of many model features, an update of the applied operational loads and boundary conditions as well as the creation of automatic post processing procedures. Currently the GMCS is used to support several significant assembly and commissioning steps of W7-X that involve the cryostat system, e.g. the removal of temporary supports beneath the MB, transfer of the PV from temporary to the final supports and evacuation of the cryostat. In the upcoming months the model will be used for further support of the commissioning of W7-X which includes the first evacuation of the PV.

  20. Modeling human papillomavirus and cervical cancer in the United States for analyses of screening and vaccination

    Directory of Open Access Journals (Sweden)

    Ortendahl Jesse


    Full Text Available Abstract Background To provide quantitative insight into current U.S. policy choices for cervical cancer prevention, we developed a model of human papillomavirus (HPV and cervical cancer, explicitly incorporating uncertainty about the natural history of disease. Methods We developed a stochastic microsimulation of cervical cancer that distinguishes different HPV types by their incidence, clearance, persistence, and progression. Input parameter sets were sampled randomly from uniform distributions, and simulations undertaken with each set. Through systematic reviews and formal data synthesis, we established multiple epidemiologic targets for model calibration, including age-specific prevalence of HPV by type, age-specific prevalence of cervical intraepithelial neoplasia (CIN, HPV type distribution within CIN and cancer, and age-specific cancer incidence. For each set of sampled input parameters, likelihood-based goodness-of-fit (GOF scores were computed based on comparisons between model-predicted outcomes and calibration targets. Using 50 randomly resampled, good-fitting parameter sets, we assessed the external consistency and face validity of the model, comparing predicted screening outcomes to independent data. To illustrate the advantage of this approach in reflecting parameter uncertainty, we used the 50 sets to project the distribution of health outcomes in U.S. women under different cervical cancer prevention strategies. Results Approximately 200 good-fitting parameter sets were identified from 1,000,000 simulated sets. Modeled screening outcomes were externally consistent with results from multiple independent data sources. Based on 50 good-fitting parameter sets, the expected reductions in lifetime risk of cancer with annual or biennial screening were 76% (range across 50 sets: 69–82% and 69% (60–77%, respectively. The reduction from vaccination alone was 75%, although it ranged from 60% to 88%, reflecting considerable parameter

  1. GSEVM v.2: MCMC software to analyse genetically structured environmental variance models

    DEFF Research Database (Denmark)

    Ibáñez-Escriche, N; Garcia, M; Sorensen, D


    This note provides a description of software that allows to fit Bayesian genetically structured variance models using Markov chain Monte Carlo (MCMC). The gsevm v.2 program was written in Fortran 90. The DOS and Unix executable programs, the user's guide, and some example files are freely available...... for research purposes at The main feature of the program is to compute Monte Carlo estimates of marginal posterior distributions of parameters of interest. The program is quite flexible, allowing the user to fit a variety of linear models at the level of the mean...

  2. Studies of the Earth Energy Budget and Water Cycle Using Satellite Observations and Model Analyses (United States)

    Campbell, G. G.; VonderHarr, T. H.; Randel, D. L.; Kidder, S. Q.


    During this research period we have utilized the ERBE data set in comparisons to surface properties and water vapor observations in the atmosphere. A relationship between cloudiness and surface temperature anomalies was found. This same relationship was found in a general circulation model, verifying the model. The attempt to construct a homogeneous time series from Nimbus 6, Nimbus 7 and ERBE data is not complete because we are still waiting for the ERBE reanalysis to be completed. It will be difficult to merge the Nimbus 6 data in because its observations occurred when the average weather was different than the other periods, so regression adjustments are not effective.

  3. Empirical analyses of a choice model that captures ordering among attribute values

    DEFF Research Database (Denmark)

    Mabit, Stefan Lindhard


    an alternative additionally because it has the highest price. In this paper, we specify a discrete choice model that takes into account the ordering of attribute values across alternatives. This model is used to investigate the effect of attribute value ordering in three case studies related to alternative-fuel...... vehicles, mode choice, and route choice. In our application to choices among alternative-fuel vehicles, we see that especially the price coefficient is sensitive to changes in ordering. The ordering effect is also found in the applications to mode and route choice data where both travel time and cost...

  4. Selection of asset investment models by hospitals: examination of influencing factors, using Switzerland as an example. (United States)

    Eicher, Bernhard


    Hospitals are responsible for a remarkable part of the annual increase in healthcare expenditure. This article examines one of the major cost drivers, the expenditure for investment in hospital assets. The study, conducted in Switzerland, identifies factors that influence hospitals' investment decisions. A suggestion on how to categorize asset investment models is presented based on the life cycle of an asset, and its influencing factors defined based on transaction cost economics. The influence of five factors (human asset specificity, physical asset specificity, uncertainty, bargaining power, and privacy of ownership) on the selection of an asset investment model is examined using a two-step fuzzy-set Qualitative Comparative Analysis. The research shows that outsourcing-oriented asset investment models are particularly favored in the presence of two combinations of influencing factors: First, if technological uncertainty is high and both human asset specificity and bargaining power of a hospital are low. Second, if assets are very specific, technological uncertainty is high and there is a private hospital with low bargaining power, outsourcing-oriented asset investment models are favored too. Using Qualitative Comparative Analysis, it can be demonstrated that investment decisions of hospitals do not depend on isolated influencing factors but on a combination of factors. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  5. Survival data analyses in ecotoxicology: critical effect concentrations, methods and models. What should we use? (United States)

    Forfait-Dubuc, Carole; Charles, Sandrine; Billoir, Elise; Delignette-Muller, Marie Laure


    In ecotoxicology, critical effect concentrations are the most common indicators to quantitatively assess risks for species exposed to contaminants. Three types of critical effect concentrations are classically used: lowest/ no observed effect concentration (LOEC/NOEC), LC( x) (x% lethal concentration) and NEC (no effect concentration). In this article, for each of these three types of critical effect concentration, we compared methods or models used for their estimation and proposed one as the most appropriate. We then compared these critical effect concentrations to each other. For that, we used nine survival data sets corresponding to D. magna exposition to nine different contaminants, for which the time-course of the response was monitored. Our results showed that: (i) LOEC/NOEC values at day 21 were method-dependent, and that the Cochran-Armitage test with a step-down procedure appeared to be the most protective for the environment; (ii) all tested concentration-response models we compared gave close values of LC50 at day 21, nevertheless the Weibull model had the lowest global mean deviance; (iii) a simple threshold NEC-model both concentration and time dependent more completely described whole data (i.e. all timepoints) and enabled a precise estimation of the NEC. We then compared the three critical effect concentrations and argued that the use of the NEC might be a good option for environmental risk assessment.

  6. Cyclodextrin--piroxicam inclusion complexes: analyses by mass spectrometry and molecular modelling (United States)

    Gallagher, Richard T.; Ball, Christopher P.; Gatehouse, Deborah R.; Gates, Paul J.; Lobell, Mario; Derrick, Peter J.


    Mass spectrometry has been used to investigate the natures of non-covalent complexes formed between the anti-inflammatory drug piroxicam and [alpha]-, [beta]- and [gamma]-cyclodextrins. Energies of these complexes have been calculated by means of molecular modelling. There is a correlation between peak intensities in the mass spectra and the calculated energies.

  7. Quantitative analyses and modelling to support achievement of the 2020 goals for nine neglected tropical diseases

    NARCIS (Netherlands)

    T.D. Hollingsworth (T. Déirdre); E.R. Adams (Emily R.); R.M. Anderson (Roy); K. Atkins (Katherine); S. Bartsch (Sarah); M-G. Basáñez (María-Gloria); M. Behrend (Matthew); D.J. Blok (David); L.A.C. Chapman (Lloyd A. C.); L.E. Coffeng (Luc); O. Courtenay (Orin); R.E. Crump (Ron E.); S.J. de Vlas (Sake); A.P. Dobson (Andrew); L. Dyson (Louise); H. Farkas (Hajnal); A.P. Galvani (Alison P.); M. Gambhir (Manoj); D. Gurarie (David); M.A. Irvine (Michael A.); S. Jervis (Sarah); M.J. Keeling (Matt J.); L. Kelly-Hope (Louise); C. King (Charles); B.Y. Lee (Bruce Y.); E.A. le Rutte (Epke); T.M. Lietman (Thomas M.); M. Ndeffo-Mbah (Martial); G.F. Medley (Graham F.); E. Michael (Edwin); A. Pandey (Abhishek); J.K. Peterson (Jennifer K.); A. Pinsent (Amy); T.C. Porco (Travis C.); J.H. Richardus (Jan Hendrik); L. Reimer (Lisa); K.S. Rock (Kat S.); B.K. Singh (Brajendra K.); W.A. Stolk (Wilma); S. Swaminathan (Subramanian); S.J. Torr (Steve J.); J. Townsend (Jeffrey); J. Truscott (James); M. Walker (Martin); A. Zoueva (Alexandra)


    textabstractQuantitative analysis and mathematical models are useful tools in informing strategies to control or eliminate disease. Currently, there is an urgent need to develop these tools to inform policy to achieve the 2020 goals for neglected tropical diseases (NTDs). In this paper we give an

  8. Analyses of gust fronts by means of limited area NWP model outputs

    Czech Academy of Sciences Publication Activity Database

    Kašpar, Marek

    67-68, - (2003), s. 559-572 ISSN 0169-8095 R&D Projects: GA ČR GA205/00/1451 Institutional research plan: CEZ:AV0Z3042911 Keywords : gust front * limited area NWP model * output Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.012, year: 2003

  9. Using Latent Trait Measurement Models to Analyse Attitudinal Data: A Synthesis of Viewpoints. (United States)

    Andrich, David

    A Rasch model for ordered response categories is derived and it is shown that it retains the key features of both the Thurstone and Likert approaches to studying attitude. Key features of the latter approaches are reviewed. Characteristics in common with the Thurstone approach are: statements are scaled with respect to their affective values;…

  10. Lightning NOx Statistics Derived by NASA Lightning Nitrogen Oxides Model (LNOM) Data Analyses (United States)

    Koshak, William; Peterson, Harold


    What is the LNOM? The NASA Marshall Space Flight Center (MSFC) Lightning Nitrogen Oxides Model (LNOM) [Koshak et al., 2009, 2010, 2011; Koshak and Peterson 2011, 2013] analyzes VHF Lightning Mapping Array (LMA) and National Lightning Detection Network(TradeMark) (NLDN) data to estimate the lightning nitrogen oxides (LNOx) produced by individual flashes. Figure 1 provides an overview of LNOM functionality. Benefits of LNOM: (1) Does away with unrealistic "vertical stick" lightning channel models for estimating LNOx; (2) Uses ground-based VHF data that maps out the true channel in space and time to < 100 m accuracy; (3) Therefore, true channel segment height (ambient air density) is used to compute LNOx; (4) True channel length is used! (typically tens of kilometers since channel has many branches and "wiggles"); (5) Distinction between ground and cloud flashes are made; (6) For ground flashes, actual peak current from NLDN used to compute NOx from lightning return stroke; (7) NOx computed for several other lightning discharge processes (based on Cooray et al., 2009 theory): (a) Hot core of stepped leaders and dart leaders, (b) Corona sheath of stepped leader, (c) K-change, (d) Continuing Currents, and (e) M-components; and (8) LNOM statistics (see later) can be used to parameterize LNOx production for regional air quality models (like CMAQ), and for global chemical transport models (like GEOS-Chem).

  11. Testing Mediation Using Multiple Regression and Structural Equation Modeling Analyses in Secondary Data (United States)

    Li, Spencer D.


    Mediation analysis in child and adolescent development research is possible using large secondary data sets. This article provides an overview of two statistical methods commonly used to test mediated effects in secondary analysis: multiple regression and structural equation modeling (SEM). Two empirical studies are presented to illustrate the…

  12. Quantitative structure-activity relationship models of chemical transformations from matched pairs analyses. (United States)

    Beck, Jeremy M; Springer, Clayton


    The concepts of activity cliffs and matched molecular pairs (MMP) are recent paradigms for analysis of data sets to identify structural changes that may be used to modify the potency of lead molecules in drug discovery projects. Analysis of MMPs was recently demonstrated as a feasible technique for quantitative structure-activity relationship (QSAR) modeling of prospective compounds. Although within a small data set, the lack of matched pairs, and the lack of knowledge about specific chemical transformations limit prospective applications. Here we present an alternative technique that determines pairwise descriptors for each matched pair and then uses a QSAR model to estimate the activity change associated with a chemical transformation. The descriptors effectively group similar transformations and incorporate information about the transformation and its local environment. Use of a transformation QSAR model allows one to estimate the activity change for novel transformations and therefore returns predictions for a larger fraction of test set compounds. Application of the proposed methodology to four public data sets results in increased model performance over a benchmark random forest and direct application of chemical transformations using QSAR-by-matched molecular pairs analysis (QSAR-by-MMPA).

  13. Neural Network-Based Model for Landslide Susceptibility and Soil Longitudinal Profile Analyses

    DEFF Research Database (Denmark)

    Farrokhzad, F.; Barari, Amin; Choobbasti, A. J.


    trained with geotechnical data obtained from an investigation of the study area. The quality of the modeling was improved further by the application of some controlling techniques involved in ANN. The observed >90% overall accuracy produced by the ANN technique in both cases is promising for future...

  14. Analysing outsourcing policies in an asset management context : A six-stage model

    NARCIS (Netherlands)

    Schoenmaker, R.; Verlaan, J.G.


    Asset managers of civil infrastructure are increasingly outsourcing their maintenance. Whereas maintenance is a cyclic process, decisions to outsource decisions are often project-based, and confusing the discussion on the degree of outsourcing. This paper presents a six-stage model that facilitates

  15. Supporting custom quality models to analyse and compare open-source software

    NARCIS (Netherlands)

    D. Di Ruscio (Davide); D.S. Kolovos (Dimitrios); I. Korkontzelos (Ioannis); N. Matragkas (Nicholas); J.J. Vinju (Jurgen)


    textabstractThe analysis and comparison of open source software can be improved by means of quality models supporting the evaluation of the software systems being compared and the final decision about which of them has to be adopted. Since software quality can mean different things in different

  16. Testing a Dual Process Model of Gender-Based Violence: A Laboratory Examination. (United States)

    Berke, Danielle S; Zeichner, Amos


    The dire impact of gender-based violence on society compels development of models comprehensive enough to capture the diversity of its forms. Research has established hostile sexism (HS) as a robust predictor of gender-based violence. However, to date, research has yet to link men's benevolent sexism (BS) to physical aggression toward women, despite correlations between BS and HS and between BS and victim blaming. One model, the opposing process model of benevolent sexism (Sibley & Perry, 2010), suggests that, for men, BS acts indirectly through HS to predict acceptance of hierarchy-enhancing social policy as an expression of a preference for in-group dominance (i. e., social dominance orientation [SDO]). The extent to which this model applies to gender-based violence remains untested. Therefore, in this study, 168 undergraduate men in a U. S. university participated in a competitive reaction time task, during which they had the option to shock an ostensible female opponent as a measure of gender-based violence. Results of multiple-mediation path analyses indicated dual pathways potentiating gender-based violence and highlight SDO as a particularly potent mechanism of this violence. Findings are discussed in terms of group dynamics and norm-based violence prevention.

  17. Ultrasonic vocalizations in Shank mouse models for autism spectrum disorders: detailed spectrographic analyses and developmental profiles. (United States)

    Wöhr, Markus


    Autism spectrum disorders (ASD) are a class of neurodevelopmental disorders characterized by persistent deficits in social behavior and communication across multiple contexts, together with repetitive patterns of behavior, interests, or activities. The high concordance rate between monozygotic twins supports a strong genetic component. Among the most promising candidate genes for ASD is the SHANK gene family, including SHANK1, SHANK2 (ProSAP1), and SHANK3 (ProSAP2). SHANK genes are therefore important candidates for modeling ASD in mice and various genetic models were generated within the last few years. As the diagnostic criteria for ASD are purely behaviorally defined, the validity of mouse models for ASD strongly depends on their behavioral phenotype. Behavioral phenotyping is therefore a key component of the current translational approach and requires sensitive behavioral test paradigms with high relevance to each diagnostic symptom category. While behavioral phenotyping assays for social deficits and repetitive patterns of behavior, interests, or activities are well-established, the development of sensitive behavioral test paradigms to assess communication deficits in mice is a daunting challenge. Measuring ultrasonic vocalizations (USV) appears to be a promising strategy. In the first part of the review, an overview on the different types of mouse USV and their communicative functions will be provided. The second part is devoted to studies on the emission of USV in Shank mouse models for ASD. Evidence for communication deficits was obtained in Shank1, Shank2, and Shank3 genetic mouse models for ASD, often paralleled by behavioral phenotypes relevant to social deficits seen in ASD. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Animal models of bone cancer pain: systematic review and meta-analyses. (United States)

    Currie, Gillian L; Delaney, Ada; Bennett, Michael I; Dickenson, Anthony H; Egan, Kieren J; Vesterinen, Hanna M; Sena, Emily S; Macleod, Malcolm R; Colvin, Lesley A; Fallon, Marie T


    Pain can significantly decrease the quality of life of patients with advanced cancer. Current treatment strategies often provide inadequate analgesia and unacceptable side effects. Animal models of bone cancer pain are used in the development of novel pharmacological approaches. Here we conducted a systematic review and meta-analysis of publications describing in vivo modelling of bone cancer pain in which behavioural, general health, macroscopic, histological, biochemical, or electrophysiological outcomes were reported and compared to appropriate controls. In all, 150 publications met our inclusion criteria, describing 38 different models of bone cancer pain. Reported methodological quality was low; only 31% of publications reported blinded assessment of outcome, and 11% reported random allocation to group. No publication reported a sample size calculation. Studies that reported measures to reduce bias reported smaller differences in behavioural outcomes between tumour-bearing and control animals, and studies that presented a statement regarding a conflict of interest reported larger differences in behavioural outcomes. Larger differences in behavioural outcomes were reported in female animals, when cancer cells were injected into either the tibia or femur, and when MatLyLu prostate or Lewis Lung cancer cells were used. Mechanical-evoked pain behaviours were most commonly reported; however, the largest difference was observed in spontaneous pain behaviours. In the spinal cord astrocyte activation and increased levels of Substance P receptor internalisation, c-Fos, dynorphin, tumor necrosis factor-α and interleukin-1β have been reported in bone cancer pain models, suggesting several potential therapeutic targets. However, the translational impact of animal models on clinical pain research could be enhanced by improving methodological quality. Copyright © 2013. Published by Elsevier B.V.

  19. Analyses of Spring Barley Evapotranspiration Rates Based on Gradient Measurements and Dual Crop Coefficient Model

    Directory of Open Access Journals (Sweden)

    Gabriela Pozníková


    Full Text Available The yield of agricultural crops depends on water availability to a great extent. According some projections, the likelihood of stress caused by drought is increasing in future climates expected for the Central Europe. Therefore, in order to manage agro-ecosystems properly, it is necessary to know water demand of particular crops as precisely as possible. Evapotranspiration (ET is the main part of water balance which takes the water from agro-ecosystems away. The ET consists of evaporation from the soil (E and transpiration (T through the stomata of plants. In this study, we investigated ET of spring barley 1-ha field (Domanínek, Czech Republic measured by Bowen ratio/energy balance method during growing period 2013 (May 8 to July 31. Special focus was dedicated to comparison of barley ET with the reference grass ETo calculated according FAO-56 model, i.e. the determination of barley crop coefficient (Kc. This crop coefficient was subsequently separated into soil evaporation (Ke and transpiration fraction (Kcb by adjusting soil and phenological parameters of dual crop coefficient model to minimize the root mean square error between measured and modelled ET. The resulting Kcb of barley was 0.98 during mid-growing period and 0.05 during initial and end periods. According to FAO-56, typical values are 1.10 and 0.15 for Kcb mid and Kcb end, respectively. Modelled and measured ET show satisfactory agreement with root mean square error equal 0.41 mm. Based on the sums of ET and E for the whole growing season of the spring barley, ET partitioning by FAO-56 dual crop coefficient model resulted in E/ET ratio being 0.24.

  20. A CAD Approach to Developing Mass Distribution and Composition Models for Spaceflight Radiation Risk Analyses (United States)

    Zapp, E.; Shelfer, T.; Semones, E.; Johnson, A.; Weyland, M.; Golightly, M.; Smith, G.; Dardano, C.

    For roughly the past three decades, combinatorial geometries have been the predominant mode for the development of mass distribution models associated with the estimation of radiological risk for manned space flight. Examples of these are the MEVDP (Modified Elemental Volume Dose Program) vehicle representation of Liley and Hamilton, and the quadratic functional representation of the CAM/CAF (Computerized Anatomical Male/Female) human body models as modified by Billings and Yucker. These geometries, have the advantageous characteristics of being simple for a familiarized user to maintain, and because of the relative lack of any operating system or run-time library dependence, they are also easy to transfer from one computing platform to another. Unfortunately they are also limited in the amount of modeling detail possible, owing to the abstract geometric representation. In addition, combinatorial representations are also known to be error-prone in practice, since there is no convenient method for error identification (i.e. overlap, etc.), and extensive calculation and/or manual comparison may is often necessary to demonstrate that the geometry is adequately represented. We present an alternate approach linking materials -specific, CAD-based mass models directly to geometric analysis tools requiring no approximation with respect to materials , nor any meshing (i.e. tessellation) of the representative geometry. A new approach to ray tracing is presented which makes use of the fundamentals of the CAD representation to perform geometric analysis directly on the NURBS (Non-Uniform Rational BSpline) surfaces themselves. In this way we achieve a framework for- the rapid, precise development and analysis of materials-specific mass distribution models.

  1. Evaluation of a dentoalveolar model for testing mouthguards: stress and strain analyses. (United States)

    Verissimo, Crisnicaw; Costa, Paulo Victor Moura; Santos-Filho, Paulo César Freitas; Fernandes-Neto, Alfredo Júlio; Tantbirojn, Daranee; Versluis, Antheunis; Soares, Carlos José


    Custom-fitted mouthguards are devices used to decrease the likelihood of dental trauma. The aim of this study was to develop an experimental bovine dentoalveolar model with periodontal ligament to evaluate mouthguard shock absorption, and impact strain and stress behavior. A pendulum impact device was developed to perform the impact tests with two different impact materials (steel ball and baseball). Five bovine jaws were selected with standard age and dimensions. Six-mm mouthguards were made for the impact tests. The jaws were fixed in a pendulum device and impacts were performed from 90, 60, and 45° angles, with and without mouthguard. Strain gauges were attached at the palatal surface of the impacted tooth. The strain and shock absorption of the mouthguards was calculated and data were analyzed with 3-way anova and Tukey's test (α = 0.05). Two-dimensional finite element models were created based on the cross-section of the bovine dentoalveolar model used in the experiment. A nonlinear dynamic impact analysis was performed to evaluate the strain and stress distributions. Without mouthguards, the increase in impact angulation significantly increased strains and stresses. Mouthguards reduced strain and stress values. Impact velocity, impact object (steel ball or baseball), and mouthguard presence affected the impact stresses and strains in a bovine dentoalveolar model. Experimental strain measurements and finite element models predicted similar behavior; therefore, both methodologies are suitable for evaluating the biomechanical performance of mouthguards. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Examining the link between patient satisfaction and adherence to HIV care: a structural equation model.

    Directory of Open Access Journals (Sweden)

    Bich N Dang

    Full Text Available INTRODUCTION: Analogous to the business model of customer satisfaction and retention, patient satisfaction could serve as an innovative, patient-centered focus for increasing retention in HIV care and adherence to HAART, and ultimately HIV suppression. OBJECTIVE: To test, through structural equation modeling (SEM, a model of HIV suppression in which patient satisfaction influences HIV suppression indirectly through retention in HIV care and adherence to HAART. METHODS: We conducted a cross-sectional study of adults receiving HIV care at two clinics in Texas. Patient satisfaction was based on two validated items, one adapted from the Consumer Assessment of Healthcare Providers and Systems survey ("Would you recommend this clinic to other patients with HIV? and one adapted from the Delighted-Terrible Scale, ("Overall, how do you feel about the care you got at this clinic in the last 12 months?". A validated, single-item question measured adherence to HAART over the past 4 weeks. Retention in HIV care was based on visit constancy in the year prior to the survey. HIV suppression was defined as plasma HIV RNA <48 copies/mL at the time of the survey. We used SEM to test hypothesized relationships. RESULTS: The analyses included 489 patients (94% of eligible patients. The patient satisfaction score had a mean of 8.5 (median 9.2 on a 0- to 10- point scale. A total of 46% reported "excellent" adherence, 76% had adequate retention, and 70% had HIV suppression. In SEM analyses, patient satisfaction with care influences retention in HIV care and adherence to HAART, which in turn serve as key determinants of HIV suppression (all p<.0001. CONCLUSIONS: Patient satisfaction may have direct effects on retention in HIV care and adherence to HAART. Interventions to improve the care experience, without necessarily targeting objective clinical performance measures, could serve as an innovative method for optimizing HIV outcomes.

  3. Evaluation et analyse de sensibilite du modele CERES-Maize en conditions alsaciennes


    Plantureux, Sylvain; Girardin, Philippe; Fouquet, D.; Chapot, Jean Yves


    CERES-Maize est un modèle de simulation de la croissance et du développement du maïs élaboré et validé aux Etats-Unis. Afin d’estimer les possibilités de transposition du modèle dans des conditions européennes, des simulations ont été réalisées pour 2 variétés de maïs (LG11 et DEA) cultivées en Alsace 2 années consécutives. Pour chaque variété, le modèle a été calibré sur 1 année et validé sur la suivante. L’analyse de sensibilité des paramètres liés à la variété et au sol montre que la r...

  4. Analysing the strength of friction stir welded dissimilar aluminium alloys using Sugeno Fuzzy model (United States)

    Barath, V. R.; Vaira Vignesh, R.; Padmanaban, R.


    Friction stir welding (FSW) is a promising solid state joining technique for aluminium alloys. In this study, FSW trials were conducted on two dissimilar plates of aluminium alloy AA2024 and AA7075 by varying the tool rotation speed (TRS) and welding speed (WS). Tensile strength (TS) of the joints were measured and a Sugeno - Fuzzy model was developed to interconnect the FSW process parameters with the tensile strength. From the developed model, it was observed that the optimum heat generation at WS of 15 mm.min-1 and TRS of 1050 rpm resulted in dynamic recovery and dynamic recrystallization of the material. This refined the grains in the FSW zone and resulted in peak tensile strength among the tested specimens. Crest parabolic trend was observed in tensile strength with variation of TRS from 900 rpm to 1200 rpm and TTS from 10 mm.min-1 to 20 mm.min-1.

  5. Evaluation and Improvement of Cloud and Convective Parameterizations from Analyses of ARM Observations and Models

    Energy Technology Data Exchange (ETDEWEB)

    Del Genio, Anthony D. [NASA Goddard Inst. for Space Studies (GISS), New York, NY (United States)


    Over this period the PI and his performed a broad range of data analysis, model evaluation, and model improvement studies using ARM data. These included cloud regimes in the TWP and their evolution over the MJO; M-PACE IOP SCM-CRM intercomparisons; simulations of convective updraft strength and depth during TWP-ICE; evaluation of convective entrainment parameterizations using TWP-ICE simulations; evaluation of GISS GCM cloud behavior vs. long-term SGP cloud statistics; classification of aerosol semi-direct effects on cloud cover; depolarization lidar constraints on cloud phase; preferred states of the winter Arctic atmosphere, surface, and sub-surface; sensitivity of convection to tropospheric humidity; constraints on the parameterization of mesoscale organization from TWP-ICE WRF simulations; updraft and downdraft properties in TWP-ICE simulated convection; insights from long-term ARM records at Manus and Nauru.

  6. Modelling and Analysing Access Control Policies in XACML 3.0

    DEFF Research Database (Denmark)

    Ramli, Carroline Dewi Puspa Kencana

    and verification of properties of XACML policies. Overall, we focus into two different area. The first part focuses on the access control language. More specifically our focus is on the understanding XACML 3.0. The second part focuses on how we use Logic Programming (LP) to model access control policies. We show...... semantics is described normatively using natural language. The use of English text in standardisation leads to the risk of misinterpretation and ambiguity. In order to avoid this drawback, we define an abstract syntax of XACML 3.0 and a formal XACML semantics. Second, we propose a logic-based XACML analysis...... framework using Answer Set Programming (ASP). With ASP we model an XACML PDP that loads XACML policies and evaluates XACML requests against these policies. The expressivity of ASP and the existence of efficient implementations of the answer set semantics provide the means for declarative specification...


    Energy Technology Data Exchange (ETDEWEB)

    Talamo, A.; Gohar, Y.


    This paper analyzes the YALINA Thermal subcritical assembly of Belarus using two different Monte Carlo transport programs, SERPENT and MCNP. The MCNP model is based on combinatorial geometry and universes hierarchy, while the SERPENT model is based on Stereolithography geometry. The latter consists of unstructured triangulated surfaces defined by the normal and vertices. This geometry format is used by 3D printers and it has been created by: the CUBIT software, MATLAB scripts, and C coding. All the Monte Carlo simulations have been performed using the ENDF/B-VII.0 nuclear data library. Both MCNP and SERPENT share the same geometry specifications, which describe the facility details without using any material homogenization. Three different configurations have been studied with different number of fuel rods. The three fuel configurations use 216, 245, or 280 fuel rods, respectively. The numerical simulations show that the agreement between SERPENT and MCNP results is within few tens of pcms.

  8. Modeling Freight Ocean Rail and Truck Transportation Flows to Support Policy Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Gearhart, Jared Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wang, Hao [Cornell Univ., Ithaca, NY (United States); Nozick, Linda Karen [Cornell Univ., Ithaca, NY (United States); Xu, Ningxiong [Cornell Univ., Ithaca, NY (United States)


    Freight transportation represents about 9.5% of GDP, is responsible for about 8% of greenhouse gas emissions and supports the import and export of about 3.6 trillion in international trade; hence it is important that our national freight transportation system is designed and operated efficiently and embodies user fees and other policies that balance costs and environmental consequences. Hence, this paper develops a mathematical model to estimate international and domestic freight flows across ocean, rail and truck modes which can be used to study the impacts of changes in our infrastructure as well as the imposition of new user fees and changes in operating policies. This model is applied to two case studies: (1) a disruption of the maritime ports at Los Angeles/Long Beach similar to the impacts that would be felt in an earthquake; and (2) implementation of new user fees at the California ports.

  9. Integrate urban‐scale seismic hazard analyses with the U.S. National Seismic Hazard Model (United States)

    Moschetti, Morgan P.; Luco, Nicolas; Frankel, Arthur; Petersen, Mark D.; Aagaard, Brad T.; Baltay, Annemarie S.; Blanpied, Michael; Boyd, Oliver; Briggs, Richard; Gold, Ryan D.; Graves, Robert; Hartzell, Stephen; Rezaeian, Sanaz; Stephenson, William J.; Wald, David J.; Williams, Robert A.; Withers, Kyle


    For more than 20 yrs, damage patterns and instrumental recordings have highlighted the influence of the local 3D geologic structure on earthquake ground motions (e.g., M">M 6.7 Northridge, California, Gao et al., 1996; M">M 6.9 Kobe, Japan, Kawase, 1996; M">M 6.8 Nisqually, Washington, Frankel, Carver, and Williams, 2002). Although this and other local‐scale features are critical to improving seismic hazard forecasts, historically they have not been explicitly incorporated into the U.S. National Seismic Hazard Model (NSHM, national model and maps), primarily because the necessary basin maps and methodologies were not available at the national scale. Instead,...

  10. Analyses of the energy-dependent single separable potential models for the NN scattering

    International Nuclear Information System (INIS)

    Ahmad, S.S.; Beghi, L.


    Starting from a systematic study of the salient features regarding the quantum-mechanical two-particle scattering off an energy-dependent (ED) single separable potential and its connection with the rank-2 energy-independent (EI) separable potential in the T-(K-) amplitude formulation, the present status of the ED single separable potential models due to Tabakin (M1), Garcilazo (M2) and Ahmad (M3) has been discussed. It turned out that the incorporation of a self-consistent optimization procedure improves considerably the results of the 1 S 0 and 3 S 1 scattering phase shifts for the models (M2) and (M3) up to the CM wave number q=2.5 fm -1 , although the extrapolation of the results up to q=10 fm -1 reveals that the two models follow the typical behaviour of the well-known super-soft core potentials. It has been found that a variant of (M3) - i.e. (M4) involving one more parameter - gives the phase shifts results which are generally in excellent agreement with the data up to q=2.5 fm -1 and the extrapolation of the results for the 1 S 0 case in the higher wave number range not only follows the corresponding data qualitatively but also reflects a behaviour similar to the Reid soft core and Hamada-Johnston potentials together with a good agreement with the recent [4/3] Pade fits. A brief discussion regarding the features resulting from the variations in the ED parts of all the four models under consideration and their correlations with the inverse scattering theory methodology concludes the paper. (author)

  11. Analyses of Spring Barley Evapotranspiration Rates Based on Gradient Measurements and Dual Crop Coefficient Model

    Czech Academy of Sciences Publication Activity Database

    Pozníková, Gabriela; Fischer, Milan; Pohanková, Eva; Trnka, Miroslav


    Roč. 62, č. 5 (2014), s. 1079-1086 ISSN 1211-8516 R&D Projects: GA MŠk LH12037; GA MŠk(CZ) EE2.3.20.0248 Institutional support: RVO:67179843 Keywords : evapotranspiration * dual crop coefficient model * Bowen ratio/energy balance method * transpiration * soil evaporation * spring barley Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7)

  12. Modeling and analyses of postulated UF6 release accidents in gaseous diffusion plant

    International Nuclear Information System (INIS)

    Kim, S.H.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W.; Carter, J.C.; Dyer, R.H.


    Computer models have been developed to simulate the transient behavior of aerosols and vapors as a result of a postulated accident involving the release of uranium hexafluoride (UF 6 ) into the process building of a gaseous diffusion plant. UF 6 undergoes an exothermic chemical reaction with moisture (H 2 O) in the air to form hydrogen fluoride (HF) and radioactive uranyl fluoride (UO 2 F 2 ). As part of a facility-wide safety evaluation, this study evaluated source terms consisting of UO 2 F 2 as well as HF during a postulated UF 6 release accident in a process building. In the postulated accident scenario, ∼7900 kg (17,500 lb) of hot UF 6 vapor is released over a 5 min period from the process piping into the atmosphere of a large process building. UO 2 F 2 mainly remains as airborne-solid particles (aerosols), and HF is in a vapor form. Some UO 2 F 2 aerosols are removed from the air flow due to gravitational settling. The HF and the remaining UO 2 F 2 are mixed with air and exhausted through the building ventilation system. The MELCOR computer code was selected for simulating aerosols and vapor transport in the process building. MELCOR model was first used to develop a single volume representation of a process building and its results were compared with those from past lumped parameter models specifically developed for studying UF 6 release accidents. Preliminary results indicate that MELCOR predicted results (using a lumped formulation) are comparable with those from previously developed models

  13. Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 2

    International Nuclear Information System (INIS)

    Gwaltney, R.C.; Bolt, S.E.; Bryson, J.W.


    Model 2 in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. Both the cylinder and the nozzle of model 2 had outside diameters of 10 in., giving a d 0 /D 0 ratio of 1.0, and both had outside diameter/thickness ratios of 100. Sixteen separate loading cases in which one end of the cylinder was rigidly held were analyzed. An internal pressure loading, three mutually perpendicular force components, and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. In addition to these 13 loadings, 3 additional loads were applied to the nozzle (in-plane bending moment, out-of-plane bending moment, and axial force) with the free end of the cylinder restrained. The experimental stress distributions for each of the 16 loadings were obtained using 152 three-gage strain rosettes located on the inner and outer surfaces. All the 16 loading cases were also analyzed theoretically using a finite-element shell analysis. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good general agreement, and it is felt that the analysis would be satisfactory for most engineering purposes. (auth)

  14. Consequence modeling for nuclear weapons probabilistic cost/benefit analyses of safety retrofits

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, T.F.; Peters, L.; Serduke, F.J.D.; Hall, C.; Stephens, D.R.


    The consequence models used in former studies of costs and benefits of enhanced safety retrofits are considered for (1) fuel fires; (2) non-nuclear detonations; and, (3) unintended nuclear detonations. Estimates of consequences were made using a representative accident location, i.e., an assumed mixed suburban-rural site. We have explicitly quantified land- use impacts and human-health effects (e.g. , prompt fatalities, prompt injuries, latent cancer fatalities, low- levels of radiation exposure, and clean-up areas). Uncertainty in the wind direction is quantified and used in a Monte Carlo calculation to estimate a range of results for a fuel fire with uncertain respirable amounts of released Pu. We define a nuclear source term and discuss damage levels of concern. Ranges of damages are estimated by quantifying health impacts and property damages. We discuss our dispersal and prompt effects models in some detail. The models used to loft the Pu and fission products and their particle sizes are emphasized.

  15. Analysing the origin of long-range interactions in proteins using lattice models

    Directory of Open Access Journals (Sweden)

    Unger Ron


    Full Text Available Abstract Background Long-range communication is very common in proteins but the physical basis of this phenomenon remains unclear. In order to gain insight into this problem, we decided to explore whether long-range interactions exist in lattice models of proteins. Lattice models of proteins have proven to capture some of the basic properties of real proteins and, thus, can be used for elucidating general principles of protein stability and folding. Results Using a computational version of double-mutant cycle analysis, we show that long-range interactions emerge in lattice models even though they are not an input feature of them. The coupling energy of both short- and long-range pairwise interactions is found to become more positive (destabilizing in a linear fashion with increasing 'contact-frequency', an entropic term that corresponds to the fraction of states in the conformational ensemble of the sequence in which the pair of residues is in contact. A mathematical derivation of the linear dependence of the coupling energy on 'contact-frequency' is provided. Conclusion Our work shows how 'contact-frequency' should be taken into account in attempts to stabilize proteins by introducing (or stabilizing contacts in the native state and/or through 'negative design' of non-native contacts.

  16. Drying of mint leaves in a solar dryer and under open sun: Modelling, performance analyses

    International Nuclear Information System (INIS)

    Akpinar, E. Kavak


    In this study was investigated the thin-layer drying characteristics in solar dryer with forced convection and under open sun with natural convection of mint leaves, and, performed energy analysis and exergy analysis of solar drying process of mint leaves. An indirect forced convection solar dryer consisting of a solar air collector and drying cabinet was used in the experiments. The drying data were fitted to ten the different mathematical models. Among the models, Wang and Singh model for the forced solar drying and the natural sun drying were found to best explain thin-layer drying behaviour of mint leaves. Using the first law of thermodynamics, the energy analysis throughout solar drying process was estimated. However, exergy analysis during solar drying process was determined by applying the second law of thermodynamics. Energy utilization ratio (EUR) values of drying cabinet varied in the ranges between 7.826% and 46.285%. The values of exergetic efficiency were found to be in the range of 34.760-87.717%. The values of improvement potential varied between 0 and 0.017 kJ s -1 . Energy utilization ratio and improvement potential decreased with increasing drying time and ambient temperature while exergetic efficiency increased.

  17. Bag-model analyses of proton-antiproton scattering and atomic bound states

    International Nuclear Information System (INIS)

    Alberg, M.A.; Freedman, R.A.; Henley, E.M.; Hwang, W.P.; Seckel, D.; Wilets, L.


    We study proton-antiproton (pp-bar ) scattering using the static real potential of Bryan and Phillips outside a cutoff radius rsub0 and two different shapes for the imaginary potential inside a radius R*. These forms, motivated by bag models, are a one-gluon-annihilation potential and a simple geometric-overlap form. In both cases there are three adjustable parameters: the effective bag radius R*, the effective strong coupling constant αsubssup*, and rsub0. There is also a choice for the form of the real potential inside the cutoff radius rsub0. Analysis of the pp-bar scattering data in the laboratory-momentum region 0.4--0.7 GeV/c yields an effective nucleon bag radius R* in the range 0.6--1.1 fm, with the best fit obtained for R* = 0.86 fm. Arguments are presented that the deduced value of R* is likely to be an upper bound on the isolated nucleon bag radius. The present results are consistent with the range of bag radii in current bag models. We have also used the resultant optical potential to calculate the shifts and widths of the sup3Ssub1 and sup1Ssub0 atomic bound states of the pp-bar system. For both states we find upward (repulsive) shifts and widths of about 1 keV. We find no evidence for narrow, strongly bound pp-bar states in our potential model

  18. Reproduction of the Yucca Mountain Project TSPA-LA Uncertainty and Sensitivity Analyses and Preliminary Upgrade of Models

    Energy Technology Data Exchange (ETDEWEB)

    Hadgu, Teklu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nuclear Waste Disposal Research and Analysis; Appel, Gordon John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nuclear Waste Disposal Research and Analysis


    Sandia National Laboratories (SNL) continued evaluation of total system performance assessment (TSPA) computing systems for the previously considered Yucca Mountain Project (YMP). This was done to maintain the operational readiness of the computing infrastructure (computer hardware and software) and knowledge capability for total system performance assessment (TSPA) type analysis, as directed by the National Nuclear Security Administration (NNSA), DOE 2010. This work is a continuation of the ongoing readiness evaluation reported in Lee and Hadgu (2014) and Hadgu et al. (2015). The TSPA computing hardware (CL2014) and storage system described in Hadgu et al. (2015) were used for the current analysis. One floating license of GoldSim with Versions 9.60.300, 10.5 and 11.1.6 was installed on the cluster head node, and its distributed processing capability was mapped on the cluster processors. Other supporting software were tested and installed to support the TSPA-type analysis on the server cluster. The current tasks included verification of the TSPA-LA uncertainty and sensitivity analyses, and preliminary upgrade of the TSPA-LA from Version 9.60.300 to the latest version 11.1. All the TSPA-LA uncertainty and sensitivity analyses modeling cases were successfully tested and verified for the model reproducibility on the upgraded 2014 server cluster (CL2014). The uncertainty and sensitivity analyses used TSPA-LA modeling cases output generated in FY15 based on GoldSim Version 9.60.300 documented in Hadgu et al. (2015). The model upgrade task successfully converted the Nominal Modeling case to GoldSim Version 11.1. Upgrade of the remaining of the modeling cases and distributed processing tasks will continue. The 2014 server cluster and supporting software systems are fully operational to support TSPA-LA type analysis.

  19. Towards an Industrial Application of Statistical Uncertainty Analysis Methods to Multi-physical Modelling and Safety Analyses

    International Nuclear Information System (INIS)

    Zhang, Jinzhao; Segurado, Jacobo; Schneidesch, Christophe


    Since 1980's, Tractebel Engineering (TE) has being developed and applied a multi-physical modelling and safety analyses capability, based on a code package consisting of the best estimate 3D neutronic (PANTHER), system thermal hydraulic (RELAP5), core sub-channel thermal hydraulic (COBRA-3C), and fuel thermal mechanic (FRAPCON/FRAPTRAN) codes. A series of methodologies have been developed to perform and to license the reactor safety analysis and core reload design, based on the deterministic bounding approach. Following the recent trends in research and development as well as in industrial applications, TE has been working since 2010 towards the application of the statistical sensitivity and uncertainty analysis methods to the multi-physical modelling and licensing safety analyses. In this paper, the TE multi-physical modelling and safety analyses capability is first described, followed by the proposed TE best estimate plus statistical uncertainty analysis method (BESUAM). The chosen statistical sensitivity and uncertainty analysis methods (non-parametric order statistic method or bootstrap) and tool (DAKOTA) are then presented, followed by some preliminary results of their applications to FRAPCON/FRAPTRAN simulation of OECD RIA fuel rod codes benchmark and RELAP5/MOD3.3 simulation of THTF tests. (authors)

  20. Numerical examinations of simplified spondylodesis models concerning energy absorption in magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Hadert Nicole


    Full Text Available Metallic implants in magnetic resonance imaging (MRI are a potential safety risk since the energy absorption may increase temperature of the surrounding tissue. The temperature rise is highly dependent on implant size. Numerical examinations can be used to calculate the energy absorption in terms of the specific absorption rate (SAR induced by MRI on orthopaedic implants. This research presents the impact of titanium osteosynthesis spine implants, called spondylodesis, deduced by numerical examinations of energy absorption in simplified spondylodesis models placed in 1.5 T and 3.0 T MRI body coils. The implants are modelled along with a spine model consisting of vertebrae and disci intervertebrales thus extending previous investigations [1], [2]. Increased SAR values are observed at the ends of long implants, while at the center SAR is significantly lower. Sufficiently short implants show increased SAR along the complete length of the implant. A careful data analysis reveals that the particular anatomy, i.e. vertebrae and disci intervertebrales, has a significant effect on SAR. On top of SAR profile due to the implant length, considerable SAR variations at small scale are observed, e.g. SAR values at vertebra are higher than at disc positions.

  1. Examining the Correlates of Women's Use of Sexual Coercion: Proposing an Explanatory Model. (United States)

    Bouffard, Jeffrey A; Bouffard, Leana A; Miller, Holly A


    Research in the last few years has begun to examine the prevalence of female sexual offending as well as attempting to understand the predictors of sexually coercive behavior among women. Although women engage in sexual coercion significantly less often than men, more research on female sexual coercion is warranted. The current study provides an exploratory examination of the relationship between several attitudinal, experiential, and situational factors, and the use of various sexual coercion tactics among a sample of 582 sexually active, female undergraduate students, as well as proposing an explanatory model of female sexual coercion. Results indicate that several variables that are significant predictors of sexual aggression for men are also predictive for women. However, these variables seem to work differently in predicting sexually coercive behavior for women. Implications for theory and further study are discussed. © The Author(s) 2015.

  2. 3D Modeling of Lower Extremities With Biplanar Radiographs: Reliability of Measures on Subsequent Examinations. (United States)

    Westberry, David E; Carpenter, Ashley M


    Biplanar radiography with 3-dimensional (3D) modeling (EOS) provides a comprehensive assessment of lower limb alignment in an upright weight-bearing position with less radiation than conventional radiography. A study was performed to assess the consistency and reliability of 2 lower extremity 3D biplanar radiograph models created at least 1 year apart in a pediatric population. All patients who had 2 lower extremity radiographic evaluations with EOS performed at visits a minimum of 1 year apart were reviewed. Digital radiographs, of lower extremities in both frontal and sagittal planes, were acquired simultaneously, using the EOS system. The 3D reconstruction of the images was achieved utilizing the SterEOS software. Pelvic position, femoral and tibial anatomy, and the torsional profile were evaluated and compared using t tests. In total, 53 patients with a mean age of 11.7 years (range, 6.1 to 18.9 y) met inclusion criteria. When comparing 3D models between visits, minimal differences were noted in proximal femoral anatomy and pelvic alignment (pelvic incidence, sacral slope, sagittal tilt, neck shaft angle). Expected differences in femoral and tibial length corresponded with normal longitudinal growth between visits. Sagittal plane knee position varied widely between examinations. Femoral and/or tibial rotational osteotomies were performed in 37% of extremities between examinations. After femoral derotational osteotomy, a significant difference in femoral anteversion was appreciated when comparing preoperative and postoperative 3D models. However, this difference was less than the expected difference based on the anatomic correction achieved intraoperatively. No differences were noted in tibial torsion measures after tibial derotational osteotomy. The 3D modeling based on biplanar radiographs provides consistent and reliable measures of pelvic and hip joint anatomy of the lower extremity. Patient positioning may influence the reproducibility of knee alignment

  3. Analyses of Methods and Algorithms for Modelling and Optimization of Biotechnological Processes

    Directory of Open Access Journals (Sweden)

    Stoyan Stoyanov


    Full Text Available A review of the problems in modeling, optimization and control of biotechnological processes and systems is given in this paper. An analysis of existing and some new practical optimization methods for searching global optimum based on various advanced strategies - heuristic, stochastic, genetic and combined are presented in the paper. Methods based on the sensitivity theory, stochastic and mix strategies for optimization with partial knowledge about kinetic, technical and economic parameters in optimization problems are discussed. Several approaches for the multi-criteria optimization tasks are analyzed. The problems concerning optimal controls of biotechnological systems are also discussed.

  4. Using Rasch Modeling to Re-Evaluate Rapid Malaria Diagnosis Test Analyses

    Directory of Open Access Journals (Sweden)

    Dawit G. Ayele


    Full Text Available The objective of this study was to demonstrate the use of the Rasch model by assessing the appropriateness of the demographic, social-economic and geographic factors in providing a total score in malaria RDT in accordance with the model’s expectations. The baseline malaria indicator survey was conducted in Amhara, Oromiya and Southern Nation Nationalities and People (SNNP regions of Ethiopia by The Carter Center in 2007. The result shows high reliability and little disordering of thresholds with no evidence of differential item functioning.

  5. Fiskeoppdrett og verdsettelse : en analyse av resultatjustering og modeller for identifikasjon av slik aktivitet


    Aaker, Harald


    Regnskapsinformasjon skal være relevant og pålitelig, men det vil alltid være skjønn forbundet med verdsettelsen.Usaklig skjønn omtales som resultatjustering (”Earnings management”) og regnskaps-manipulasjon. Det er store metodeproblemer innen ”earnings management” – forskningen, da den aktive tilpasningen i stor grad er skjult. I de senere år har ulike modeller for estimering av unormale tidsavgrensninger (”discretionary accruals”) dominert. Problemet er i å estimere de normale tidsavgrensni...

  6. On the Structure of Personality Disorder Traits: Conjoint Analyses of the CAT-PD, PID-5, and NEO-PI-3 Trait Models (United States)

    Wright, Aidan G.C.; Simms, Leonard J.


    The current study examines the relations among contemporary models of pathological and normal range personality traits. Specifically, we report on (a) conjoint exploratory factor analyses of the Computerized Adaptive Test of Personality Disorder static form (CAT-PD-SF) with the Personality Inventory for the DSM-5 (PID-5; Krueger et al., 2012) and NEO Personality Inventory-3 First Half (NEI-PI-3FH; McCrae & Costa, 2007), and (b) unfolding hierarchical analyses of the three measures in a large general psychiatric outpatient sample (N = 628; 64% Female). A five-factor solution provided conceptually coherent alignment among the CAT-PD-SF, PID-5, and NEO-PI-3FH scales. Hierarchical solutions suggested that higher-order factors bear strong resemblance to dimensions that emerge from structural models of psychopathology (e.g., Internalizing and Externalizing spectra). These results demonstrate that the CAT-PD-SF adheres to the consensual structure of broad trait domains at the five-factor level. Additionally, patterns of scale loadings further inform questions of structure and bipolarity of facet and domain level constructs. Finally, hierarchical analyses strengthen the argument for using broad dimensions that span normative and pathological functioning to scaffold a quantitatively derived phenotypic structure of psychopathology to orient future research on explanatory, etiological, and maintenance mechanisms. PMID:24588061

  7. On the structure of personality disorder traits: conjoint analyses of the CAT-PD, PID-5, and NEO-PI-3 trait models. (United States)

    Wright, Aidan G C; Simms, Leonard J


    The current study examines the relations among contemporary models of pathological and normal range personality traits. Specifically, we report on (a) conjoint exploratory factor analyses of the Computerized Adaptive Test of Personality Disorder static form (CAT-PD-SF) with the Personality Inventory for the Diagnostic and Statistical Manual of Mental Disorders, fifth edition and NEO Personality Inventory-3 First Half, and (b) unfolding hierarchical analyses of the three measures in a large general psychiatric outpatient sample (n = 628; 64% Female). A five-factor solution provided conceptually coherent alignment among the CAT-PD-SF, PID-5, and NEO-PI-3FH scales. Hierarchical solutions suggested that higher-order factors bear strong resemblance to dimensions that emerge from structural models of psychopathology (e.g., Internalizing and Externalizing spectra). These results demonstrate that the CAT-PD-SF adheres to the consensual structure of broad trait domains at the five-factor level. Additionally, patterns of scale loadings further inform questions of structure and bipolarity of facet and domain level constructs. Finally, hierarchical analyses strengthen the argument for using broad dimensions that span normative and pathological functioning to scaffold a quantitatively derived phenotypic structure of psychopathology to orient future research on explanatory, etiological, and maintenance mechanisms.

  8. Using the Single Prolonged Stress Model to Examine the Pathophysiology of PTSD

    Directory of Open Access Journals (Sweden)

    Rimenez R. Souza


    Full Text Available The endurance of memories of emotionally arousing events serves the adaptive role of minimizing future exposure to danger and reinforcing rewarding behaviors. However, following a traumatic event, a subset of individuals suffers from persistent pathological symptoms such as those seen in posttraumatic stress disorder (PTSD. Despite the availability of pharmacological treatments and evidence-based cognitive behavioral therapy, a considerable number of PTSD patients do not respond to the treatment, or show partial remission and relapse of the symptoms. In controlled laboratory studies, PTSD patients show deficient ability to extinguish conditioned fear. Failure to extinguish learned fear could be responsible for the persistence of PTSD symptoms such as elevated anxiety, arousal, and avoidance. It may also explain the high non-response and dropout rates seen during treatment. Animal models are useful for understanding the pathophysiology of the disorder and the development of new treatments. This review examines studies in a rodent model of PTSD with the goal of identifying behavioral and physiological factors that predispose individuals to PTSD symptoms. Single prolonged stress (SPS is a frequently used rat model of PTSD that involves exposure to several successive stressors. SPS rats show PTSD-like symptoms, including impaired extinction of conditioned fear. Since its development by the Liberzon lab in 1997, the SPS model has been referred to by more than 200 published papers. Here we consider the findings of these studies and unresolved questions that may be investigated using the model.

  9. Incorporating Measurement Error from Modeled Air Pollution Exposures into Epidemiological Analyses. (United States)

    Samoli, Evangelia; Butland, Barbara K


    Outdoor air pollution exposures used in epidemiological studies are commonly predicted from spatiotemporal models incorporating limited measurements, temporal factors, geographic information system variables, and/or satellite data. Measurement error in these exposure estimates leads to imprecise estimation of health effects and their standard errors. We reviewed methods for measurement error correction that have been applied in epidemiological studies that use model-derived air pollution data. We identified seven cohort studies and one panel study that have employed measurement error correction methods. These methods included regression calibration, risk set regression calibration, regression calibration with instrumental variables, the simulation extrapolation approach (SIMEX), and methods under the non-parametric or parameter bootstrap. Corrections resulted in small increases in the absolute magnitude of the health effect estimate and its standard error under most scenarios. Limited application of measurement error correction methods in air pollution studies may be attributed to the absence of exposure validation data and the methodological complexity of the proposed methods. Future epidemiological studies should consider in their design phase the requirements for the measurement error correction method to be later applied, while methodological advances are needed under the multi-pollutants setting.


    Directory of Open Access Journals (Sweden)

    R. A. Barut


    Full Text Available On August 17th 1999, a Mw 7.4 earthquake struck the city of Izmit in the north-west of Turkey. This event was one of the most devastating earthquakes of the twentieth century. The epicentre of the Izmit earthquake was on the North Anatolian Fault (NAF which is one of the most active right-lateral strike-slip faults on earth. However, this earthquake offers an opportunity to study how strain is accommodated in an inter-segment region of a large strike slip fault. In order to determine the Izmit earthquake post-seismic effects, the authors modelled Coulomb stress changes of the aftershocks, as well as using the deformation measurement techniques of Interferometric Synthetic Aperture Radar (InSAR and Global Navigation Satellite System (GNSS. The authors have shown that InSAR and GNSS observations over a time period of three months after the earthquake combined with Coulomb Stress Change Modelling can explain the fault zone expansion, as well as the deformation of the northern region of the NAF. It was also found that there is a strong agreement between the InSAR and GNSS results for the post-seismic phases of investigation, with differences less than 2mm, and the standard deviation of the differences is less than 1mm.

  11. Subchannel and Computational Fluid Dynamic Analyses of a Model Pin Bundle

    Energy Technology Data Exchange (ETDEWEB)

    Gairola, A.; Arif, M.; Suh, K. Y. [Seoul National Univ., Seoul (Korea, Republic of)


    The current study showed that the simplistic approach of subchannel analysis code MATRA was not good in capturing the physical behavior of the coolant inside the rod bundle. With the incorporation of more detailed geometry of the grid spacer in the CFX code it was possible to approach the experimental values. However, it is vital to incorporate more advanced turbulence mixing models to more realistically simulate behavior of the liquid metal coolant inside the model pin bundle in parallel with the incorporation of the bottom and top grid structures. In the framework of the 11{sup th} international meeting of International Association for Hydraulic Research and Engineering (IAHR) working group on the advanced reactor thermal hydraulics a standard problem was conducted. The quintessence of the problem was to check on the hydraulics and heat transfer in a novel pin bundle with different pitch to rod diameter ratio and heat flux cooled by liquid metal. The standard problem stems from the field of nuclear safety research with the idea of validating and checking the performances of computer codes against the experimental results. Comprehensive checks between the two will succor in improving the dependability and exactness of the codes used for accident simulations.

  12. Integration of 3d Models and Diagnostic Analyses Through a Conservation-Oriented Information System (United States)

    Mandelli, A.; Achille, C.; Tommasi, C.; Fassi, F.


    In the recent years, mature technologies for producing high quality virtual 3D replicas of Cultural Heritage (CH) artefacts has grown thanks to the progress of Information Technologies (IT) tools. These methods are an efficient way to present digital models that can be used with several scopes: heritage managing, support to conservation, virtual restoration, reconstruction and colouring, art cataloguing and visual communication. The work presented is an emblematic case of study oriented to the preventive conservation through monitoring activities, using different acquisition methods and instruments. It was developed inside a project founded by Lombardy Region, Italy, called "Smart Culture", which was aimed to realise a platform that gave the users the possibility to easily access to the CH artefacts, using as an example a very famous statue. The final product is a 3D reality-based model that contains a lot of information inside it, and that can be consulted through a common web browser. In the end, it was possible to define the general strategies oriented to the maintenance and the valorisation of CH artefacts, which, in this specific case, must consider the integration of different techniques and competencies, to obtain a complete, accurate and continuative monitoring of the statue.


    Directory of Open Access Journals (Sweden)

    A. Mandelli


    Full Text Available In the recent years, mature technologies for producing high quality virtual 3D replicas of Cultural Heritage (CH artefacts has grown thanks to the progress of Information Technologies (IT tools. These methods are an efficient way to present digital models that can be used with several scopes: heritage managing, support to conservation, virtual restoration, reconstruction and colouring, art cataloguing and visual communication. The work presented is an emblematic case of study oriented to the preventive conservation through monitoring activities, using different acquisition methods and instruments. It was developed inside a project founded by Lombardy Region, Italy, called “Smart Culture”, which was aimed to realise a platform that gave the users the possibility to easily access to the CH artefacts, using as an example a very famous statue. The final product is a 3D reality-based model that contains a lot of information inside it, and that can be consulted through a common web browser. In the end, it was possible to define the general strategies oriented to the maintenance and the valorisation of CH artefacts, which, in this specific case, must consider the integration of different techniques and competencies, to obtain a complete, accurate and continuative monitoring of the statue.

  14. Analysing and combining atmospheric general circulation model simulations forced by prescribed SST: northern extratropical response

    Directory of Open Access Journals (Sweden)

    K. Maynard


    Full Text Available The ECHAM 3.2 (T21, ECHAM 4 (T30 and LMD (version 6, grid-point resolution with 96 longitudes × 72 latitudes atmospheric general circulation models were integrated through the period 1961 to 1993 forced with the same observed Sea Surface Temperatures (SSTs as compiled at the Hadley Centre. Three runs were made for each model starting from different initial conditions. The mid-latitude circulation pattern which maximises the covariance between the simulation and the observations, i.e. the most skilful mode, and the one which maximises the covariance amongst the runs, i.e. the most reproducible mode, is calculated as the leading mode of a Singular Value Decomposition (SVD analysis of observed and simulated Sea Level Pressure (SLP and geopotential height at 500 hPa (Z500 seasonal anomalies. A common response amongst the different models, having different resolution and parametrization should be considered as a more robust atmospheric response to SST than the same response obtained with only one model. A robust skilful mode is found mainly in December-February (DJF, and in June-August (JJA. In DJF, this mode is close to the SST-forced pattern found by Straus and Shukla (2000 over the North Pacific and North America with a wavy out-of-phase between the NE Pacific and the SE US on the one hand and the NE North America on the other. This pattern evolves in a NAO-like pattern over the North Atlantic and Europe (SLP and in a more N-S tripole on the Atlantic and European sector with an out-of-phase between the middle Europe on the one hand and the northern and southern parts on the other (Z500. There are almost no spatial shifts between either field around North America (just a slight eastward shift of the highest absolute heterogeneous correlations for SLP relative to the Z500 ones. The time evolution of the SST-forced mode is moderatly to strongly related to the ENSO/LNSO events but the spread amongst the ensemble of runs is not systematically related

  15. Innovative three-dimensional neutronics analyses directly coupled with cad models of geometrically complex fusion systems

    International Nuclear Information System (INIS)

    Sawan, M.; Wilson, P.; El-Guebaly, L.; Henderson, D.; Sviatoslavsky, G.; Bohm, T.; Kiedrowski, B.; Ibrahim, A.; Smith, B.; Slaybaugh, R.; Tautges, T.


    Fusion systems are, in general, geometrically complex requiring detailed three-dimensional (3-D) nuclear analysis. This analysis is required to address tritium self-sufficiency, nuclear heating, radiation damage, shielding, and radiation streaming issues. To facilitate such calculations, we developed an innovative computational tool that is based on the continuous energy Monte Carlo code MCNP and permits the direct use of CAD-based solid models in the ray-tracing. This allows performing the neutronics calculations in a model that preserves the geometrical details without any simplification, eliminates possible human error in modeling the geometry for MCNP, and allows faster design iterations. In addition to improving the work flow for simulating complex 3- D geometries, it allows a richer representation of the geometry compared to the standard 2nd order polynomial representation. This newly developed tool has been successfully tested for a detailed 40 degree sector benchmark of the International Thermonuclear Experimental Reactor (ITER). The calculations included determining the poloidal variation of the neutron wall loading, flux and nuclear heating in the divertor components, nuclear heating in toroidal field coils, and radiation streaming in the mid-plane port. The tool has been applied to perform 3-D nuclear analysis for several fusion designs including the ARIES Compact Stellarator (ARIES-CS), the High Average Power Laser (HAPL) inertial fusion power plant, and ITER first wall/shield (FWS) modules. The ARIES-CS stellarator has a first wall shape and a plasma profile that varies toroidally within each field period compared to the uniform toroidal shape in tokamaks. Such variation cannot be modeled analytically in the standard MCNP code. The impact of the complex helical geometry and the non-uniform blanket and divertor on the overall tritium breeding ratio and total nuclear heating was determined. In addition, we calculated the neutron wall loading variation in

  16. A review on design of experiments and surrogate models in aircraft real-time and many-query aerodynamic analyses (United States)

    Yondo, Raul; Andrés, Esther; Valero, Eusebio


    Full scale aerodynamic wind tunnel testing, numerical simulation of high dimensional (full-order) aerodynamic models or flight testing are some of the fundamental but complex steps in the various design phases of recent civil transport aircrafts. Current aircraft aerodynamic designs have increase in complexity (multidisciplinary, multi-objective or multi-fidelity) and need to address the challenges posed by the nonlinearity of the objective functions and constraints, uncertainty quantification in aerodynamic problems or the restrained computational budgets. With the aim to reduce the computational burden and generate low-cost but accurate models that mimic those full order models at different values of the design variables, Recent progresses have witnessed the introduction, in real-time and many-query analyses, of surrogate-based approaches as rapid and cheaper to simulate models. In this paper, a comprehensive and state-of-the art survey on common surrogate modeling techniques and surrogate-based optimization methods is given, with an emphasis on models selection and validation, dimensionality reduction, sensitivity analyses, constraints handling or infill and stopping criteria. Benefits, drawbacks and comparative discussions in applying those methods are described. Furthermore, the paper familiarizes the readers with surrogate models that have been successfully applied to the general field of fluid dynamics, but not yet in the aerospace industry. Additionally, the review revisits the most popular sampling strategies used in conducting physical and simulation-based experiments in aircraft aerodynamic design. Attractive or smart designs infrequently used in the field and discussions on advanced sampling methodologies are presented, to give a glance on the various efficient possibilities to a priori sample the parameter space. Closing remarks foster on future perspectives, challenges and shortcomings associated with the use of surrogate models by aircraft industrial

  17. A model using marginal efficiency of investment to analyse carbon and nitrogen interactions in forested ecosystems (United States)

    Thomas, R. Q.; Williams, M.


    Carbon (C) and nitrogen (N) cycles are coupled in terrestrial ecosystems through multiple processes including photosynthesis, tissue allocation, respiration, N fixation, N uptake, and decomposition of litter and soil organic matter. Capturing the constraint of N on terrestrial C uptake and storage has been a focus of the Earth System modelling community. Here we explore the trade-offs and sensitivities of allocating C and N to different tissues in order to optimize the productivity of plants using a new, simple model of ecosystem C-N cycling and interactions (ACONITE). ACONITE builds on theory related to plant economics in order to predict key ecosystem properties (leaf area index, leaf C:N, N fixation, and plant C use efficiency) based on the optimization of the marginal change in net C or N uptake associated with a change in allocation of C or N to plant tissues. We simulated and evaluated steady-state and transient ecosystem stocks and fluxes in three different forest ecosystems types (tropical evergreen, temperate deciduous, and temperate evergreen). Leaf C:N differed among the three ecosystem types (temperate deciduous plant traits. Gross primary productivity (GPP) and net primary productivity (NPP) estimates compared well to observed fluxes at the simulation sites. A sensitivity analysis revealed that parameterization of the relationship between leaf N and leaf respiration had the largest influence on leaf area index and leaf C:N. Also, a widely used linear leaf N-respiration relationship did not yield a realistic leaf C:N, while a more recently reported non-linear relationship simulated leaf C:N that compared better to the global trait database than the linear relationship. Overall, our ability to constrain leaf area index and allow spatially and temporally variable leaf C:N can help address challenges simulating these properties in ecosystem and Earth System models. Furthermore, the simple approach with emergent properties based on coupled C-N dynamics has

  18. Use of model analysis to analyse Thai students’ attitudes and approaches to physics problem solving (United States)

    Rakkapao, S.; Prasitpong, S.


    This study applies the model analysis technique to explore the distribution of Thai students’ attitudes and approaches to physics problem solving and how those attitudes and approaches change as a result of different experiences in physics learning. We administered the Attitudes and Approaches to Problem Solving (AAPS) survey to over 700 Thai university students from five different levels, namely students entering science, first-year science students, and second-, third- and fourth-year physics students. We found that their inferred mental states were generally mixed. The largest gap between physics experts and all levels of the students was about the role of equations and formulas in physics problem solving, and in views towards difficult problems. Most participants of all levels believed that being able to handle the mathematics is the most important part of physics problem solving. Most students’ views did not change even though they gained experiences in physics learning.

  19. Statistical Analyses and Modeling of the Implementation of Agile Manufacturing Tactics in Industrial Firms

    Directory of Open Access Journals (Sweden)

    Mohammad D. AL-Tahat


    Full Text Available This paper provides a review and introduction on agile manufacturing. Tactics of agile manufacturing are mapped into different production areas (eight-construct latent: manufacturing equipment and technology, processes technology and know-how, quality and productivity improvement, production planning and control, shop floor management, product design and development, supplier relationship management, and customer relationship management. The implementation level of agile manufacturing tactics is investigated in each area. A structural equation model is proposed. Hypotheses are formulated. Feedback from 456 firms is collected using five-point-Likert-scale questionnaire. Statistical analysis is carried out using IBM SPSS and AMOS. Multicollinearity, content validity, consistency, construct validity, ANOVA analysis, and relationships between agile components are tested. The results of this study prove that the agile manufacturing tactics have positive effect on the overall agility level. This conclusion can be used by manufacturing firms to manage challenges when trying to be agile.

  20. Use of CFD modelling for analysing air parameters in auditorium halls (United States)

    Cichowicz, Robert


    Modelling with the use of numerical methods is currently the most popular method of solving scientific as well as engineering problems. Thanks to the use of computer methods it is possible for example to comprehensively describe the conditions in a given room and to determine thermal comfort, which is a complex issue including subjective sensations of the persons in a given room. The article presents the results of measurements and numerical computing that enabled carrying out the assessment of environment parameters, taking into consideration microclimate, temperature comfort, speeds in the zone of human presence and dustiness in auditory halls. For this purpose measurements of temperature, relative humidity and dustiness were made with the use of a digital microclimate meter and a laser dust particles counter. Thanks to the above by using the application DesignBuilder numerical computing was performed and the obtained results enabled determining PMV comfort indicator in selected rooms.

  1. Statistical modelling of measurement errors in gas chromatographic analyses of blood alcohol content. (United States)

    Moroni, Rossana; Blomstedt, Paul; Wilhelm, Lars; Reinikainen, Tapani; Sippola, Erkki; Corander, Jukka


    Headspace gas chromatographic measurements of ethanol content in blood specimens from suspect drunk drivers are routinely carried out in forensic laboratories. In the widely established standard statistical framework, measurement errors in such data are represented by Gaussian distributions for the population of blood specimens at any given level of ethanol content. It is known that the variance of measurement errors increases as a function of the level of ethanol content and the standard statistical approach addresses this issue by replacing the unknown population variances by estimates derived from large sample using a linear regression model. Appropriate statistical analysis of the systematic and random components in the measurement errors is necessary in order to guarantee legally sound security corrections reported to the police authority. Here we address this issue by developing a novel statistical approach that takes into account any potential non-linearity in the relationship between the level of ethanol content and the variability of measurement errors. Our method is based on standard non-parametric kernel techniques for density estimation using a large database of laboratory measurements for blood specimens. Furthermore, we address also the issue of systematic errors in the measurement process by a statistical model that incorporates the sign of the error term in the security correction calculations. Analysis of a set of certified reference materials (CRMs) blood samples demonstrates the importance of explicitly handling the direction of the systematic errors in establishing the statistical uncertainty about the true level of ethanol content. Use of our statistical framework to aid quality control in the laboratory is also discussed. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  2. Comparative ultrastructural analyses of platelets and fibrin networks using the murine model of asthma. (United States)

    Pretorius, E; Ekpo, O E; Smit, E


    The murine Balb/c asthma model has been used successfully for a number of in vivo immunological applications and for testing novel therapeutics, and it is a reliable, clinically relevant facsimile of the human disease. Here we investigate whether this model can be used to study other components of the human body, e.g. ultrastructure. In particular, we investigate the effect of the phytomedicine Euphorbia hirta (used to treat asthma), on the ultrastructure of fibrin as well as platelets, cellular structures that both play an important role in the coagulation process. Hydrocortisone is used as positive control. Ultrastructure of the fibrin networks and platelets of control mice were compared to mice that were asthmatic, treated with two concentrations of hydrocortisone and one concentration of the plant material. Results indicate control mice possess major, thick fibers and minor thin fibers as well as tight round platelet aggregates with typical pseudopodia formation. Minor fibers of asthmatic mice have a netlike appearance covering the major fibers, while the platelets seem to form loosely connected, granular aggregates. Both concentrations of hydrocortisone make the fibrin more fragile and that platelet morphology changes form a tight platelet aggregate to a more granular aggregate not closely fused to each other. We conclude that E. hirta does not impact on the fragility of the fibrin and that it prevents the minor fibers to form the dense netlike layer over the major fibers, as is seen in untreated asthmatic mice. This ultrastructural morphology might give us better insight into asthma and the possible new treatment regimes.

  3. Estimating organ doses from tube current modulated CT examinations using a generalized linear model. (United States)

    Bostani, Maryam; McMillan, Kyle; Lu, Peiyun; Kim, Grace Hyun J; Cody, Dianna; Arbique, Gary; Greenberg, S Bruce; DeMarco, John J; Cagnon, Chris H; McNitt-Gray, Michael F


    Currently, available Computed Tomography dose metrics are mostly based on fixed tube current Monte Carlo (MC) simulations and/or physical measurements such as the size specific dose estimate (SSDE). In addition to not being able to account for Tube Current Modulation (TCM), these dose metrics do not represent actual patient dose. The purpose of this study was to generate and evaluate a dose estimation model based on the Generalized Linear Model (GLM), which extends the ability to estimate organ dose from tube current modulated examinations by incorporating regional descriptors of patient size, scanner output, and other scan-specific variables as needed. The collection of a total of 332 patient CT scans at four different institutions was approved by each institution's IRB and used to generate and test organ dose estimation models. The patient population consisted of pediatric and adult patients and included thoracic and abdomen/pelvis scans. The scans were performed on three different CT scanner systems. Manual segmentation of organs, depending on the examined anatomy, was performed on each patient's image series. In addition to the collected images, detailed TCM data were collected for all patients scanned on Siemens CT scanners, while for all GE and Toshiba patients, data representing z-axis-only TCM, extracted from the DICOM header of the images, were used for TCM simulations. A validated MC dosimetry package was used to perform detailed simulation of CT examinations on all 332 patient models to estimate dose to each segmented organ (lungs, breasts, liver, spleen, and kidneys), denoted as reference organ dose values. Approximately 60% of the data were used to train a dose estimation model, while the remaining 40% was used to evaluate performance. Two different methodologies were explored using GLM to generate a dose estimation model: (a) using the conventional exponential relationship between normalized organ dose and size with regional water equivalent diameter

  4. On Deriving Requirements for the Surface Mass Balance forcing of a Greenland Ice Sheet Model using Uncertainty Analyses (United States)

    Schlegel, N.; Larour, E. Y.; Box, J. E.


    During July of 2012, the percentage of the Greenland surface exposed to melt was the largest in recorded history. And, even though evidence of increased melt rates had been captured by remote sensing observations throughout the last decade, this particular event took the community by surprise. How Greenland ice flow will respond to such an event or to increased frequencies of extreme melt events in the future is unclear, as it requires detailed comprehension of Greenland surface climate and the ice sheet's sensitivity to associated uncertainties. With established uncertainty quantification (UQ) tools embedded within the Ice Sheet System Model (ISSM), we conduct decadal-scale forward modeling experiments to 1) quantify the spatial resolution needed to effectively force surface mass balance (SMB) in various regions of the ice sheet and 2) determine the dynamic response of Greenland outlet glaciers to variations in SMB. First, we perform sensitivity analyses to determine how perturbations in SMB affect model output; results allow us to investigate the locations where variations most significantly affect ice flow, and on what spatial scales. Next, we apply Monte-Carlo style sampling analyses to determine how errors in SMB propagate through the model as uncertainties in estimates of Greenland ice discharge and regional mass balance. This work is performed at the California Institute of Technology's Jet Propulsion Laboratory under a contract with the National Aeronautics and Space Administration's Cryosphere Program.

  5. Analyses and optimization of Lee propagation model for LoRa 868 MHz network deployments in urban areas

    Directory of Open Access Journals (Sweden)

    Dobrilović Dalibor


    Full Text Available In the recent period, fast ICT expansion and rapid appearance of new technologies raised the importance of fast and accurate planning and deployment of emerging communication technologies, especially wireless ones. In this paper is analyzed possible usage of Lee propagation model for planning, design and management of networks based on LoRa 868MHz technology. LoRa is wireless technology which can be deployed in various Internet of Things and Smart City scenarios in urban areas. The analyses are based on comparison of field measurements with model calculations. Besides the analyses of Lee propagation model usability, the possible optimization of the model is discussed as well. The research results can be used for accurate design, planning and for preparation of high-performance wireless resource management of various Internet of Things and Smart City applications in urban areas based on LoRa or similar wireless technology. The equipment used for measurements is based on open-source hardware.

  6. Parametric analyses of DEMO Divertor using two dimensional transient thermal hydraulic modelling (United States)

    Domalapally, Phani; Di Caro, Marco


    Among the options considered for cooling of the Plasma facing components of the DEMO reactor, water cooling is a conservative option because of its high heat removal capability. In this work a two-dimensional transient thermal hydraulic code is developed to support the design of the divertor for the projected DEMO reactor with water as a coolant. The mathematical model accounts for transient 2D heat conduction in the divertor section. Temperature-dependent properties are used for more accurate analysis. Correlations for single phase flow forced convection, partially developed subcooled nucleate boiling, fully developed subcooled nucleate boiling and film boiling are used to calculate the heat transfer coefficients on the channel side considering the swirl flow, wherein different correlations found in the literature are compared against each other. Correlation for the Critical Heat Flux is used to estimate its limit for a given flow conditions. This paper then investigates the results of the parametric analysis performed, whereby flow velocity, diameter of the coolant channel, thickness of the coolant pipe, thickness of the armor material, inlet temperature and operating pressure affect the behavior of the divertor under steady or transient heat fluxes. This code will help in understanding the basic parameterś effect on the behavior of the divertor, to achieve a better design from a thermal hydraulic point of view.

  7. Modelling and Analysing Deadlock in Flexible Manufacturing System using Timed Petri Net

    Directory of Open Access Journals (Sweden)

    Assem Hatem Taha


    Full Text Available Flexible manufacturing system (FMS has several advantages compared to conventional systems such as higher machine utilization, higher efficiency, less inventory, and less production time. On the other hand, FMS is expensive and complicated. One of the main problems that may happen is the deadlock. Deadlock is a case that happens when one operation or more are unable to complete their tasks because of waiting of resources that are used by other processes. This may occur due to inappropriate sharing of the resources or improper resource allocation logic which may lead to deadlock occurrence due to the complexity of assigning shared resources to different tasks in an efficient way. One of the most effective tools to model and detect the deadlocks is the petri net. In this research the Matlab software has been used to detect the deadlock in two parallel lines with one shared machines. The analysis shows that deadlock exists at transition with high utilization and place with high waiting time

  8. Alpins and thibos vectorial astigmatism analyses: proposal of a linear regression model between methods

    Directory of Open Access Journals (Sweden)

    Giuliano de Oliveira Freitas


    Full Text Available PURPOSE: To determine linear regression models between Alpins descriptive indices and Thibos astigmatic power vectors (APV, assessing the validity and strength of such correlations. METHODS: This case series prospectively assessed 62 eyes of 31 consecutive cataract patients with preoperative corneal astigmatism between 0.75 and 2.50 diopters in both eyes. Patients were randomly assorted among two phacoemulsification groups: one assigned to receive AcrySof®Toric intraocular lens (IOL in both eyes and another assigned to have AcrySof Natural IOL associated with limbal relaxing incisions, also in both eyes. All patients were reevaluated postoperatively at 6 months, when refractive astigmatism analysis was performed using both Alpins and Thibos methods. The ratio between Thibos postoperative APV and preoperative APV (APVratio and its linear regression to Alpins percentage of success of astigmatic surgery, percentage of astigmatism corrected and percentage of astigmatism reduction at the intended axis were assessed. RESULTS: Significant negative correlation between the ratio of post- and preoperative Thibos APVratio and Alpins percentage of success (%Success was found (Spearman's ρ=-0.93; linear regression is given by the following equation: %Success = (-APVratio + 1.00x100. CONCLUSION: The linear regression we found between APVratio and %Success permits a validated mathematical inference concerning the overall success of astigmatic surgery.

  9. Modelling and optimization of combined cycle power plant based on exergoeconomic and environmental analyses

    International Nuclear Information System (INIS)

    Ganjehkaviri, A.; Mohd Jaafar, M.N.; Ahmadi, P.; Barzegaravval, H.


    This research paper presents a study on a comprehensive thermodynamic modelling of a combined cycle power plant (CCPP). The effects of economic strategies and design parameters on the plant optimization are also studied. Exergoeconomic analysis is conducted in order to determine the cost of electricity and cost of exergy destruction. In addition, a comprehensive optimization study is performed to determine the optimal design parameters of the power plant. Next, the effects of economic parameters variations on the sustainability, carbon dioxide emission and fuel consumption of the plant are investigated and are presented for a typical combined cycle power plant. Therefore, the changes in economic parameters caused the balance between cash flows and fix costs of the plant changes at optimum point. Moreover, economic strategies greatly limited the maximum reasonable carbon emission and fuel consumption reduction. The results showed that by using the optimum values, the exergy efficiency increases for about 6%, while CO 2 emission decreases by 5.63%. However, the variation in the cost was less than 1% due to the fact that a cost constraint was implemented. In addition, the sensitivity analysis for the optimization study was curtailed to be carried out; therefore, the optimization process and results to two important parameters are presented and discussed.

  10. Microarray and bioinformatic analyses suggest models for carbon metabolism in the autotroph Acidithiobacillus ferrooxidans

    Energy Technology Data Exchange (ETDEWEB)

    C. Appia-ayme; R. Quatrini; Y. Denis; F. Denizot; S. Silver; F. Roberto; F. Veloso; J. Valdes; J. P. Cardenas; M. Esparza; O. Orellana; E. Jedlicki; V. Bonnefoy; D. Holmes


    Acidithiobacillus ferrooxidans is a chemolithoautotrophic bacterium that uses iron or sulfur as an energy and electron source. Bioinformatic analysis was used to identify putative genes and potential metabolic pathways involved in CO2 fixation, 2P-glycolate detoxification, carboxysome formation and glycogen utilization in At. ferrooxidans. Microarray transcript profiling was carried out to compare the relative expression of the predicted genes of these pathways when the microorganism was grown in the presence of iron versus sulfur. Several gene expression patterns were confirmed by real-time PCR. Genes for each of the above predicted pathways were found to be organized into discrete clusters. Clusters exhibited differential gene expression depending on the presence of iron or sulfur in the medium. Concordance of gene expression within each cluster, suggested that they are operons Most notably, clusters of genes predicted to be involved in CO2 fixation, carboxysome formation, 2P-glycolate detoxification and glycogen biosynthesis were up-regulated in sulfur medium, whereas genes involved in glycogen utilization were preferentially expressed in iron medium. These results can be explained in terms of models of gene regulation that suggest how A. ferrooxidans can adjust its central carbon management to respond to changing environmental conditions.

  11. Analysing hydro-mechanical behaviour of reinforced slopes through centrifuge modelling (United States)

    Veenhof, Rick; Wu, Wei


    Every year, slope instability is causing casualties and damage to properties and the environment. The behaviour of slopes during and after these kind of events is complex and depends on meteorological conditions, slope geometry, hydro-mechanical soil properties, boundary conditions and the initial state of the soils. This study describes the effects of adding reinforcement, consisting of randomly distributed polyolefin monofilament fibres or Ryegrass (Lolium), on the behaviour of medium-fine sand in loose and medium dense conditions. Direct shear tests were performed on sand specimens with different void ratios, water content and fibre or root density, respectively. To simulate the stress state of real scale field situations, centrifuge model tests were conducted on sand specimens with different slope angles, thickness of the reinforced layer, fibre density, void ratio and water content. An increase in peak shear strength is observed in all reinforced cases. Centrifuge tests show that for slopes that are reinforced the period until failure is extended. The location of shear band formation and patch displacement behaviour indicate that the design of slope reinforcement has a significant effect on the failure behaviour. Future research will focus on the effect of plant water uptake on soil cohesion.

  12. Fungal-Induced Deterioration of Mural Paintings: In Situ and Mock-Model Microscopy Analyses. (United States)

    Unković, Nikola; Grbić, Milica Ljaljević; Stupar, Miloš; Savković, Željko; Jelikić, Aleksa; Stanojević, Dragan; Vukojević, Jelena


    Fungal deterioration of frescoes was studied in situ on a selected Serbian church, and on a laboratory model, utilizing standard and newly implemented microscopy techniques. Scanning electron microscopy (SEM) with energy-dispersive X-ray confirmed the limestone components of the plaster. Pigments used were identified as carbon black, green earth, iron oxide, ocher, and an ocher/cinnabar mixture. In situ microscopy, applied via a portable microscope ShuttlePix P-400R, proved very useful for detection of invisible micro-impairments and hidden, symptomless, microbial growth. SEM and optical microscopy established that observed deterioration symptoms, predominantly discoloration and pulverization of painted layers, were due to bacterial filaments and fungal hyphal penetration, and formation of a wide range of fungal structures (i.e., melanized hyphae, chlamydospores, microcolonial clusters, Cladosporium-like conidia, and Chaetomium perithecia and ascospores). The all year-round monitoring of spontaneous and induced fungal colonization of a "mock painting" in controlled laboratory conditions confirmed the decisive role of humidity level (70.18±6.91% RH) in efficient colonization of painted surfaces, as well as demonstrated increased bioreceptivity of painted surfaces to fungal colonization when plant-based adhesives (ilinocopie, murdent), compared with organic adhesives of animal origin (bone glue, egg white), are used for pigment sizing.

  13. Modeling and Analysing of Air Filter in Air Intake System in Automobile Engine

    Directory of Open Access Journals (Sweden)

    R. Manikantan


    Full Text Available As the legislations on the emission and performance of automobiles are being made more stringent, the expected performance of all the subsystems of an internal combustion engine is also becoming crucial. Nowadays the engines are downsized, and their power increased the demand on the air intake system that has increased phenomenally. Hence, an analysis was carried on a typical air filter fitted into the intake system to determine its flow characteristics. In the present investigation, a CAD model of an existing air filter was designed, and CFD analysis was done pertaining to various operating regimes of an internal combustion engine. The numerical results were validated with the experimental data. From the postprocessed result, we can see that there is a deficit in the design of the present filter, as the bottom portion of the filter is preventing the upward movement of air. Hence, the intake passage can be rearranged to provide an upward tangential motion, which can enhance the removal of larger dust and soot particles effectively by the inertial action of air alone.

  14. A new binary model for university examination timetabling: a case study (United States)

    Komijan, Alireza Rashidi; Koupaei, Mehrdad Nouri


    Examination timetabling problem (ETP) is one of the most important issues in universities. An improper timetable may result in students' dissatisfaction as it may not let them study enough between two sequential exams. In addition, the many exams to be scheduled, the large number of students who have taken different courses, the limited number of rooms, and some constraints such as no conflict in a single student's exams make it very difficult to schedule experimentally. A mathematical programming model is required to formulate such a sophisticated problem. In this paper, a new binary model is developed for ETP. The novelty of the paper can be discussed in two directions. The first one is that a course can be offered more than once in a semester. If a course is requested by a few students, then it is enough to be offered once. If the number of students requesting a course is more than the maximum number of students who are allowed to attend a single class, then the course is multi-offered. The second novelty is that sharing a room for two simultaneous exams is allowed. Also, the model considers some hard and soft constraints, and the objective function is set in such a way that soft constraints are satisfied as much as possible. Finally, the model is applied in a sample department and is solved by GAMS.

  15. Performance of BSEd Science Graduates in Licensure Examination for Teachers: Basis for a Regression Model

    Directory of Open Access Journals (Sweden)

    Roy C. Ferrer


    Full Text Available The study determined predictors of LET performance of BSEd Science graduates of the four state universities in Region I in the September 2013 Licensure Examination for Teachers using descriptive-correlation method and documentary analysis. It found that graduates were young, dominated by female with high school average grade of 88.731, college entrance average percentage score of 59.1%, and majority attended review classes.The overall academicperformance was 1.995 while the overall LET performance was77.59. Majority passed the LET. Gender, high school average grade, college entrance score, attendance to review class and academic performance significantly predict LET performance. The regression model equation is Y = 0.153a + 0.257b – 10.767c + 1.105d – 5.459e + 75.976 with a margin of error of  4.26 where Y is LET rating; the constant is 75.976; a is college entrance test score; and b, c, d, e are averages in high school, general education, professional education, and major, respectively. Thus, in the event that male and female applicants are tied along admission requirements, males be given due consideration. Universities need to intensify admission requirements and retention policies. School administrators must provide their graduates with review classes. Faculty members should prepare examinations based on the LET examination format.

  16. Examining Equity Sensitivity: An Investigation Using the Big Five and HEXACO Models of Personality. (United States)

    Woodley, Hayden J R; Bourdage, Joshua S; Ogunfowora, Babatunde; Nguyen, Brenda


    The construct of equity sensitivity describes an individual's preference about his/her desired input to outcome ratio. Individuals high on equity sensitivity tend to be more input oriented, and are often called "Benevolents." Individuals low on equity sensitivity are more outcome oriented, and are described as "Entitleds." Given that equity sensitivity has often been described as a trait, the purpose of the present study was to examine major personality correlates of equity sensitivity, so as to inform both the nature of equity sensitivity, and the potential processes through which certain broad personality traits may relate to outcomes. We examined the personality correlates of equity sensitivity across three studies (total N = 1170), two personality models (i.e., the Big Five and HEXACO), the two most common measures of equity sensitivity (i.e., the Equity Preference Questionnaire and Equity Sensitivity Inventory), and using both self and peer reports of personality (in Study 3). Although results varied somewhat across samples, the personality variables of Conscientiousness and Honesty-Humility, followed by Agreeableness, were the most robust predictors of equity sensitivity. Individuals higher on these traits were more likely to be Benevolents, whereas those lower on these traits were more likely to be Entitleds. Although some associations between Extraversion, Openness, and Neuroticism and equity sensitivity were observed, these were generally not robust. Overall, it appears that there are several prominent personality variables underlying equity sensitivity, and that the addition of the HEXACO model's dimension of Honesty-Humility substantially contributes to our understanding of equity sensitivity.

  17. Innovative Business Model for Realization of Sustainable Supply Chain at the Outsourcing Examination of Logistics Services

    Directory of Open Access Journals (Sweden)

    Péter Tamás


    Full Text Available The issue of sustainability is becoming more and more important because of the increase in the human population and the extraction of non-renewable natural resources. We can make decisive steps towards sustainability in the fields of logistics services by improvement of logistics processes and/or application of new environment-friendly technologies. These steps are very important for companies because they have a significant effect on competitiveness. Nowadays significant changes are taking place in applied methods and technologies in the fields of logistics services as part of the 4th Industrial Revolution. Most companies are not able to keep pace with these changes in addition to carrying out their main activities by using own resources; consequently, in many cases logistics services are outsourced in the interest of maintaining or increasing competitiveness. The currently applied outsourcing examination process contains numerous shortcomings. We have elaborated a new business model to eliminate these shortcomings, namely the basic concept for an outsourcing investigation system integrated in the electronic marketplace. The paper introduces the current process of logistics service outsourcing examination and the elaborated business model concept.

  18. Analysing movements in investor’s risk aversion using the Heston volatility model

    Directory of Open Access Journals (Sweden)

    Alexie ALUPOAIEI


    Full Text Available In this paper we intend to identify and analyze, if it is the case, an “epidemiological” relationship between forecasts of professional investors and short-term developments in the EUR/RON exchange rate. Even that we don’t call a typical epidemiological model as those ones used in biology fields of research, we investigated the hypothesis according to which after the Lehman Brothers crash and implicit the generation of the current financial crisis, the forecasts of professional investors pose a significant explanatory power on the futures short-run movements of EUR/RON. How does it work this mechanism? Firstly, the professional forecasters account for the current macro, financial and political states, then they elaborate forecasts. Secondly, based on that forecasts they get positions in the Romanian exchange market for hedging and/or speculation purposes. But their positions incorporate in addition different degrees of uncertainty. In parallel, a part of their anticipations are disseminated to the public via media channels. Since some important movements are viewed within macro, financial or political fields, the positions of professsional investors from FX derivative market are activated. The current study represents a first step in that direction of analysis for Romanian case. For the above formulated objectives, in this paper different measures of EUR/RON rate volatility have been estimated and compared with implied volatilities. In a second timeframe we called the co-integration and dynamic correlation based tools in order to investigate the relationship between implied volatility and daily returns of EUR/RON exchange rate.

  19. A tool to analyse gender mainstreaming and care-giving models in support plans for informal care: case studies in Andalusia and the United Kingdom. (United States)

    García-Calvente, María Mar; Castaño-López, Esther; Mateo-Rodríguez, Inmaculada; Maroto-Navarro, Gracia; Ruiz-Cantero, María Teresa


    To present a tool to analyse the design of support plans for informal care from a gender perspective, using the plans in Andalusia and the United Kingdom as case studies. A tool was drawn up to analyse gender mainstreaming and care-giving models involved in the documents. In the gender mainstreaming aspect, a symbolic dimension (gender mainstreaming in the plan's theoretical framework and analysis of situation) and an operational dimension (gender mainstreaming in the plan's proposals and actions) were defined. Four care-giving models were analysed using the following categories: the plan's definition of carer, focal point of interest, objectives and acknowledgement or otherwise of conflict of interests. A qualitative discourse analysis methodology was used. The analysis tool used shows that the plans do not incorporate gender mainstreaming systematically, but there are interesting aspects from a gender perspective that are present at both a symbolic and an operational level. Both plans use a combination of care-giving models, but the model for superseding informal care is not included in either plan. The proposed tool proved useful for the examination of the gender perspective in the formulation of the plans selected for analysis. Both plans introduce measures to improve the quality of life of informal carers. However, gender mainstreaming also implies interventions that will change situations of sexual inequality and injustice that occur in informal care in the long term. Likewise, aspects of feminist theory must be considered in order to draw up plans and policies that are sensitive to informal care and the emancipation of women carers.

  20. Computational Modeling of Oxygen Transport in the Microcirculation: From an Experiment-Based Model to Theoretical Analyses


    Lücker, Adrien


    Oxygen supply to cells by the cardiovascular system involves multiple physical and chemical processes that aim to satisfy fluctuating metabolic demand. Regulation mechanisms range from increased heart rate to minute adaptations in the microvasculature. The challenges and limitations of experimental studies in vivo make computational models an invaluable complement. In this thesis, oxygen transport from capillaries to tissue is investigated using a new numerical model that is tailored for vali...

  1. Model-based performance and energy analyses of reverse osmosis to reuse wastewater in a PVC production site. (United States)

    Hu, Kang; Fiedler, Thorsten; Blanco, Laura; Geissen, Sven-Uwe; Zander, Simon; Prieto, David; Blanco, Angeles; Negro, Carlos; Swinnen, Nathalie


    A pilot-scale reverse osmosis (RO) followed behind a membrane bioreactor (MBR) was developed for the desalination to reuse wastewater in a PVC production site. The solution-diffusion-film model (SDFM) based on the solution-diffusion model (SDM) and the film theory was proposed to describe rejections of electrolyte mixtures in the MBR effluent which consists of dominant ions (Na + and Cl - ) and several trace ions (Ca 2+ , Mg 2+ , K + and SO 4 2- ). The universal global optimisation method was used to estimate the ion permeability coefficients (B) and mass transfer coefficients (K) in SDFM. Then, the membrane performance was evaluated based on the estimated parameters which demonstrated that the theoretical simulations were in line with the experimental results for the dominant ions. Moreover, an energy analysis model with the consideration of limitation imposed by the thermodynamic restriction was proposed to analyse the specific energy consumption of the pilot-scale RO system in various scenarios.

  2. Examining the virulence of Candida albicans transcription factor mutants using Galleria mellonella and mouse infection models

    Directory of Open Access Journals (Sweden)

    Sara eAmorim-Vaz


    Full Text Available The aim of the present study was to identify C. albicans transcription factors (TF involved in virulence. Although mice are considered the gold-standard model to study fungal virulence, mini-host infection models have been increasingly used. Here, barcoded TF mutants were first screened in mice by pools of strains and fungal burdens quantified in kidneys. Mutants of unannotated genes which generated a kidney fungal burden significantly different from that of wild-type were selected and individually examined in G. mellonella. In addition, mutants that could not be detected in mice were also tested in G. mellonella. Only 25 % of these mutants displayed matching phenotypes in both hosts, highlighting a significant discrepancy between the two models. To address the basis of this difference (pool or host effects, a set of 19 mutants tested in G. mellonella were also injected individually into mice. Matching fungal burden phenotypes were observed in 50 % of the cases, highlighting the bias due to host effects. In contrast, 33.4 % concordance was observed between pool and single strain infections in mice, thereby highlighting the bias introduced by the pool effect. After filtering the results obtained from the two infection models, mutants for MBF1 and ZCF6 were selected. Independent marker-free mutants were subsequently tested in both hosts to validate previous results. The MBF1 mutant showed impaired infection in both models, while the ZCF6 mutant was only significant in mice infections. The two mutants showed no obvious in vitro phenotypes compared with the wild-type, indicating that these genes might be specifically involved in in vivo adaptation.

  3. Examining the link between patient satisfaction and adherence to HIV care: a structural equation model. (United States)

    Dang, Bich N; Westbrook, Robert A; Black, William C; Rodriguez-Barradas, Maria C; Giordano, Thomas P


    Analogous to the business model of customer satisfaction and retention, patient satisfaction could serve as an innovative, patient-centered focus for increasing retention in HIV care and adherence to HAART, and ultimately HIV suppression. To test, through structural equation modeling (SEM), a model of HIV suppression in which patient satisfaction influences HIV suppression indirectly through retention in HIV care and adherence to HAART. We conducted a cross-sectional study of adults receiving HIV care at two clinics in Texas. Patient satisfaction was based on two validated items, one adapted from the Consumer Assessment of Healthcare Providers and Systems survey ("Would you recommend this clinic to other patients with HIV?) and one adapted from the Delighted-Terrible Scale, ("Overall, how do you feel about the care you got at this clinic in the last 12 months?"). A validated, single-item question measured adherence to HAART over the past 4 weeks. Retention in HIV care was based on visit constancy in the year prior to the survey. HIV suppression was defined as plasma HIV RNA satisfaction score had a mean of 8.5 (median 9.2) on a 0- to 10- point scale. A total of 46% reported "excellent" adherence, 76% had adequate retention, and 70% had HIV suppression. In SEM analyses, patient satisfaction with care influences retention in HIV care and adherence to HAART, which in turn serve as key determinants of HIV suppression (all psatisfaction may have direct effects on retention in HIV care and adherence to HAART. Interventions to improve the care experience, without necessarily targeting objective clinical performance measures, could serve as an innovative method for optimizing HIV outcomes.

  4. Examining the Link between Patient Satisfaction and Adherence to HIV Care: A Structural Equation Model (United States)

    Dang, Bich N.; Westbrook, Robert A.; Black, William C.; Rodriguez-Barradas, Maria C.; Giordano, Thomas P.


    Introduction Analogous to the business model of customer satisfaction and retention, patient satisfaction could serve as an innovative, patient-centered focus for increasing retention in HIV care and adherence to HAART, and ultimately HIV suppression. Objective To test, through structural equation modeling (SEM), a model of HIV suppression in which patient satisfaction influences HIV suppression indirectly through retention in HIV care and adherence to HAART. Methods We conducted a cross-sectional study of adults receiving HIV care at two clinics in Texas. Patient satisfaction was based on two validated items, one adapted from the Consumer Assessment of Healthcare Providers and Systems survey (“Would you recommend this clinic to other patients with HIV?) and one adapted from the Delighted-Terrible Scale, (“Overall, how do you feel about the care you got at this clinic in the last 12 months?”). A validated, single-item question measured adherence to HAART over the past 4 weeks. Retention in HIV care was based on visit constancy in the year prior to the survey. HIV suppression was defined as plasma HIV RNA patient satisfaction score had a mean of 8.5 (median 9.2) on a 0- to 10- point scale. A total of 46% reported “excellent” adherence, 76% had adequate retention, and 70% had HIV suppression. In SEM analyses, patient satisfaction with care influences retention in HIV care and adherence to HAART, which in turn serve as key determinants of HIV suppression (all pPatient satisfaction may have direct effects on retention in HIV care and adherence to HAART. Interventions to improve the care experience, without necessarily targeting objective clinical performance measures, could serve as an innovative method for optimizing HIV outcomes. PMID:23382948

  5. Examining the utility of satellite-based wind sheltering estimates for lake hydrodynamic modeling (United States)

    Van Den Hoek, Jamon; Read, Jordan S.; Winslow, Luke A.; Montesano, Paul; Markfort, Corey D.


    Satellite-based measurements of vegetation canopy structure have been in common use for the last decade but have never been used to estimate canopy's impact on wind sheltering of individual lakes. Wind sheltering is caused by slower winds in the wake of topography and shoreline obstacles (e.g. forest canopy) and influences heat loss and the flux of wind-driven mixing energy into lakes, which control lake temperatures and indirectly structure lake ecosystem processes, including carbon cycling and thermal habitat partitioning. Lakeshore wind sheltering has often been parameterized by lake surface area but such empirical relationships are only based on forested lakeshores and overlook the contributions of local land cover and terrain to wind sheltering. This study is the first to examine the utility of satellite imagery-derived broad-scale estimates of wind sheltering across a diversity of land covers. Using 30 m spatial resolution ASTER GDEM2 elevation data, the mean sheltering height, hs, being the combination of local topographic rise and canopy height above the lake surface, is calculated within 100 m-wide buffers surrounding 76,000 lakes in the U.S. state of Wisconsin. Uncertainty of GDEM2-derived hs was compared to SRTM-, high-resolution G-LiHT lidar-, and ICESat-derived estimates of hs, respective influences of land cover type and buffer width on hsare examined; and the effect of including satellite-based hs on the accuracy of a statewide lake hydrodynamic model was discussed. Though GDEM2 hs uncertainty was comparable to or better than other satellite-based measures of hs, its higher spatial resolution and broader spatial coverage allowed more lakes to be included in modeling efforts. GDEM2 was shown to offer superior utility for estimating hs compared to other satellite-derived data, but was limited by its consistent underestimation of hs, inability to detect within-buffer hs variability, and differing accuracy across land cover types. Nonetheless

  6. Local overfishing may be avoided by examining parameters of a spatio-temporal model. (United States)

    Carson, Stuart; Shackell, Nancy; Mills Flemming, Joanna


    Spatial erosion of stock structure through local overfishing can lead to stock collapse because fish often prefer certain locations, and fisheries tend to focus on those locations. Fishery managers are challenged to maintain the integrity of the entire stock and require scientific approaches that provide them with sound advice. Here we propose a Bayesian hierarchical spatio-temporal modelling framework for fish abundance data to estimate key parameters that define spatial stock structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). The consideration of these spatial parameters in the stock assessment process can help identify the erosion of structure and assist in preventing local overfishing. We use Atlantic cod (Gadus morhua) in eastern Canada as a case study an examine the behaviour of these parameters from the height of the fishery through its collapse. We identify clear signals in parameter behaviour under circumstances of destructive stock erosion as well as for recovery of spatial structure even when combined with a non-recovery in abundance. Further, our model reveals the spatial pattern of areas of high and low density persists over the 41 years of available data and identifies the remnant patches. Models of this sort are crucial to recovery plans if we are to identify and protect remaining sources of recolonization for Atlantic cod. Our method is immediately applicable to other exploited species.

  7. Examining the Efficiency of Models Using Tangent Coordinates or Principal Component Scores in Allometry Studies. (United States)

    Sigirli, Deniz; Ercan, Ilker


    Most of the studies in medical and biological sciences are related to the examination of geometrical properties of an organ or organism. Growth and allometry studies are important in the way of investigating the effects of diseases and the environmental factors effects on the structure of the organ or organism. Thus, statistical shape analysis has recently become more important in the medical and biological sciences. Shape is all geometrical information that remains when location, scale and rotational effects are removed from an object. Allometry, which is a relationship between size and shape, plays an important role in the development of statistical shape analysis. The aim of the present study was to compare two different models for allometry which includes tangent coordinates and principal component scores of tangent coordinates as dependent variables in multivariate regression analysis. The results of the simulation study showed that the model constructed by taking tangent coordinates as dependent variables is more appropriate than the model constructed by taking principal component scores of tangent coordinates as dependent variables, for all sample sizes.

  8. An assessment of the wind re-analyses in the modelling of an extreme sea state in the Black Sea (United States)

    Akpinar, Adem; Ponce de León, S.


    This study aims at an assessment of wind re-analyses for modelling storms in the Black Sea. A wind-wave modelling system (Simulating WAve Nearshore, SWAN) is applied to the Black Sea basin and calibrated with buoy data for three recent re-analysis wind sources, namely the European Centre for Medium-Range Weather Forecasts Reanalysis-Interim (ERA-Interim), Climate Forecast System Reanalysis (CFSR), and Modern Era Retrospective Analysis for Research and Applications (MERRA) during an extreme wave condition that occurred in the north eastern part of the Black Sea. The SWAN model simulations are carried out for default and tuning settings for deep water source terms, especially whitecapping. Performances of the best model configurations based on calibration with buoy data are discussed using data from the JASON2, TOPEX-Poseidon, ENVISAT and GFO satellites. The SWAN model calibration shows that the best configuration is obtained with Janssen and Komen formulations with whitecapping coefficient (Cds) equal to 1.8e-5 for wave generation by wind and whitecapping dissipation using ERA-Interim. In addition, from the collocated SWAN results against the satellite records, the best configuration is determined to be the SWAN using the CFSR winds. Numerical results, thus show that the accuracy of a wave forecast will depend on the quality of the wind field and the ability of the SWAN model to simulate the waves under extreme wind conditions in fetch limited wave conditions.

  9. Gamma-ray pulsar physics: gap-model populations and light-curve analyses in the Fermi era

    International Nuclear Information System (INIS)

    Pierbattista, M.


    This thesis research focusses on the study of the young and energetic isolated ordinary pulsar population detected by the Fermi gamma-ray space telescope. We compared the model expectations of four emission models and the LAT data. We found that all the models fail to reproduce the LAT detections, in particular the large number of high E objects observed. This inconsistency is not model dependent. A discrepancy between the radio-loud/radio-quiet objects ratio was also found between the observed and predicted samples. The L γ α E 0.5 relation is robustly confirmed by all the assumed models with particular agreement in the slot gap (SG) case. On luminosity bases, the intermediate altitude emission of the two pole caustic SG model is favoured. The beaming factor f Ω shows an E dependency that is slightly visible in the SG case. Estimates of the pulsar orientations have been obtained to explain the simultaneous gamma and radio light-curves. By analysing the solutions we found a relation between the observed energy cutoff and the width of the emission slot gap. This relation has been theoretically predicted. A possible magnetic obliquity α alignment with time is rejected -for all the models- on timescale of the order of 10 6 years. The light-curve morphology study shows that the outer magnetosphere gap emission (OGs) are favoured to explain the observed radio-gamma lag. The light curve moment studies (symmetry and sharpness) on the contrary favour a two pole caustic SG emission. All the model predictions suggest a different magnetic field layout with an hybrid two pole caustic and intermediate altitude emission to explain both the pulsar luminosity and light curve morphology. The low magnetosphere emission mechanism of the polar cap model, is systematically rejected by all the tests done. (author) [fr

  10. Modeling and stress analyses of a normal foot-ankle and a prosthetic foot-ankle complex. (United States)

    Ozen, Mustafa; Sayman, Onur; Havitcioglu, Hasan


    Total ankle replacement (TAR) is a relatively new concept and is becoming more popular for treatment of ankle arthritis and fractures. Because of the high costs and difficulties of experimental studies, the developments of TAR prostheses are progressing very slowly. For this reason, the medical imaging techniques such as CT, and MR have become more and more useful. The finite element method (FEM) is a widely used technique to estimate the mechanical behaviors of materials and structures in engineering applications. FEM has also been increasingly applied to biomechanical analyses of human bones, tissues and organs, thanks to the development of both the computing capabilities and the medical imaging techniques. 3-D finite element models of the human foot and ankle from reconstruction of MR and CT images have been investigated by some authors. In this study, data of geometries (used in modeling) of a normal and a prosthetic foot and ankle were obtained from a 3D reconstruction of CT images. The segmentation software, MIMICS was used to generate the 3D images of the bony structures, soft tissues and components of prosthesis of normal and prosthetic ankle-foot complex. Except the spaces between the adjacent surface of the phalanges fused, metatarsals, cuneiforms, cuboid, navicular, talus and calcaneus bones, soft tissues and components of prosthesis were independently developed to form foot and ankle complex. SOLIDWORKS program was used to form the boundary surfaces of all model components and then the solid models were obtained from these boundary surfaces. Finite element analyses software, ABAQUS was used to perform the numerical stress analyses of these models for balanced standing position. Plantar pressure and von Mises stress distributions of the normal and prosthetic ankles were compared with each other. There was a peak pressure increase at the 4th metatarsal, first metatarsal and talus bones and a decrease at the intermediate cuneiform and calcaneus bones, in

  11. An examination of the factors controlling net methylation in estuarine sediments: Results from measurements and models

    Directory of Open Access Journals (Sweden)

    Schartup A. T.


    Full Text Available An examination of the distribution of mercury and methylmercury across estuarine ecosystems in the northeast USA was completed under a number of projects. Sites ranged from Maine to the Chesapeake Bay and included both pristine and contaminated sites. In addition to measurements of bulk sediment and porewater, methylation and demethylation rates were also measured. Results showed that the relationships between sediment-porewater partitioning and methylation potential with sediment organic content are complex and that sediment organic content alone is not always a good predictor of the potential for a system to produce methylmercury. Modeling and correlations between variables suggest that the sulfur content of the system needs to be considered and for high organic content sediments, both sulfur and organic content.

  12. A re-examination of thermodynamic modelling of U-Ru binary phase diagram

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L.C.; Kaye, M.H., E-mail: [University of Ontario Institute of Technology, Oshawa, ON (Canada)


    Ruthenium (Ru) is one of the more abundant fission products (FPs) both in fast breeder reactors and thermal reactors. Post irradiation examinations (PIE) show that both 'the white metallic phase' (MoTc-Ru-Rh-Pd) and 'the other metallic phase' (U(Pd-Rh-Ru)3) are present in spent nuclear fuels. To describe this quaternary system, binary subsystems of uranium (U) with Pd, Rh, and Ru are necessary. Presently, only the U-Ru system has been thermodynamically described but with some problems. As part of research on U-Ru-Rh-Pd quaternary system, an improved consistent thermodynamic model describing the U-Ru binary phase diagram has been obtained. (author)

  13. College students coping with interpersonal stress: Examining a control-based model of coping. (United States)

    Coiro, Mary Jo; Bettis, Alexandra H; Compas, Bruce E


    The ways that college students cope with stress, particularly interpersonal stress, may be a critical factor in determining which students are at risk for impairing mental health disorders. Using a control-based model of coping, the present study examined associations between interpersonal stress, coping strategies, and symptoms. A total of 135 undergraduate students from 2 universities. Interpersonal stress, coping strategies, depression, anxiety, and somatization were assessed via self-report. Students reporting more interpersonal stress reported more depression, anxiety, and somatization, and they reported less use of engagement coping strategies and greater use of disengagement coping strategies. Engagement coping strategies accounted for a significant portion of the association between interpersonal stress and mental health symptoms. Unexpectedly, coping strategies did not moderate the association between stress and mental health symptoms. Interventions designed to improve students' coping strategies may be an effective way to reduce mental health problems on college campuses.

  14. Examine Trustiness of Medical Information Through Social Networks Using Path Models. (United States)

    Pistolis, John; Diomidous, Marianna; Zimeras, Stelios; Chardalias, Kostis; Filntisis, George


    Social networks provide an alternative way to communicate and exchange of information with various people. Especially for Health Care Professionals, information ought to be exchanged and shared between individuals for diagnosis and proposed therapies. In this research, the important sources of medical information that people trust, through the exchange of information on social networks, were analyzed based on the perceived information quality using path models. A questionnaire was developed to run the survey. Based on the answers, it seems that the surveyed population does not trust heavily the content of social networks as source of information for healthcare issues. Further research is needed to examine the trustiness of social networks as a Source of Health Care Information.

  15. Using the Stereotype Content Model to examine group depictions in Fascism: An Archival Approach. (United States)

    Durante, Federica; Volpato, Chiara; Fiske, Susan T


    The Stereotype Content Model (SCM) suggests potentially universal intergroup depictions. If universal, they should apply across history in archival data. Bridging this gap, we examined social groups descriptions during Italy's Fascist era. In Study 1, articles published in a Fascist magazine- La Difesa della Razza -were content analyzed, and results submitted to correspondence analysis. Admiration prejudice depicted ingroups; envious and contemptuous prejudices depicted specific outgroups, generally in line with SCM predictions. No paternalistic prejudice appeared; historical reasons might explain this finding. Results also fit the recently developed BIAS Map of behavioral consequences. In Study 2, ninety-six undergraduates rated the content-analysis traits on warmth and competence, without knowing their origin. They corroborated SCM's interpretations of the archival data.

  16. Examining systemic steroid Use in older inflammatory bowel disease patients using hurdle models: a cohort study. (United States)

    Johnson, Sophia L; Palta, Mari; Bartels, Christie M; Thorpe, Carolyn T; Weiss, Jennifer M; Smith, Maureen A


    Interpreting clinical guideline adherence and the appropriateness of medication regimens requires consideration of individual patient and caregiver factors. Factors leading to initiation of a medication may differ from those determining continued use. We believe this is the case for systemic steroid therapy in inflammatory bowel disease (IBD), resulting in a need to apply methods that separately consider factors associated with initiation and duration of therapy. To evaluate the relationship between patient characteristics and the frequency and duration of incident steroid use we apply a 2-part hurdle model to Medicare data. We do so in older patients with tumor necrosis factor antagonist (anti-TNFs) contraindications, as they are of special interest for compliance with Medicare-adopted, quality metrics calling for anti-TNFs and nonbiologic immune therapies to reduce steroid utilization. Many older patients have contraindications to anti-TNFs. However, nonbiologics cause adverse events that are concerning in older adults, limiting their use in this population and increasing reliance on systemic steroids. We used a national Medicare sample for 2006-2009 including patients with 12 months or greater of Parts A and B and 6 months or greater of Part D coverage, IBD confirmed with at least 2 claims for ICD-9CM 555.xx or 556.xx, anti-TNF contraindications and without contraindications to nonbiologic agents. We applied a negative binomial-logit hurdle model to examine patient characteristics associated with systemic steroid utilization. Among the 1,216 IBD patients without baseline steroid use, 21% used systemic steroids. Odds of receiving systemic steroids were greater in those younger, rural, and those receiving other agents. Available patient characteristics failed to predict longer steroid treatment duration. Our study identified differences in predictors of frequency and duration of medication use and suggests the utility of two-part models to examine drug utilization

  17. FVB/NJ Mice Are a Useful Model for Examining Cardiac Adaptations to Treadmill Exercise. (United States)

    Gibb, Andrew A; McNally, Lindsey A; Riggs, Daniel W; Conklin, Daniel J; Bhatnagar, Aruni; Hill, Bradford G


    Mice are commonly used to examine the mechanisms by which exercise improves cardiometabolic health; however, exercise compliance and adaptations are often strain-dependent or are variable due to inconsistency in exercise training protocols. In this study, we examined nocturnal/diurnal behavior, treadmill exercise compliance, and systemic as well as cardiac-specific exercise adaptations in two commonly used mouse strains, C57BL/6J, and FVB/NJ mice. Metabolic cage analysis indicated a strong nocturnal nature of C57BL/6J mice, whereas FVB/NJ mice showed no circadian element to activity, food or water intake, VO 2 , or VCO 2 . Initial exercise capacity tests revealed that, compared with C57BL/6J mice, FVB/NJ mice are capable of achieving nearly 2-fold higher workloads prior to exhaustion. FVB/NJ mice tested during the day were capable of achieving significantly more work compared with their night-tested counterparts. Following 4 weeks of training, FVB/NJ mice showed significant increases in exercise capacity as well as physiologic cardiac growth characterized by enlarged myocytes and higher mitochondrial DNA content. C57BL/6J mice showed no increases in exercise capacity or cardiac growth regardless of whether they exercised during the day or the night. This lack of adaptation in C57BL/6J mice was attributable, at least in part, to their progressive loss of compliance to the treadmill training protocol. We conclude that the FVB/NJ strain is a useful and robust mouse model for examining cardiac adaptations to treadmill exercise and that treadmill training during daytime hours does not negatively affect exercise compliance or capacity.

  18. Examining School-Based Bullying Interventions Using Multilevel Discrete Time Hazard Modeling (United States)

    Wagaman, M. Alex; Geiger, Jennifer Mullins; Bermudez-Parsai, Monica; Hedberg, E. C.


    Although schools have been trying to address bulling by utilizing different approaches that stop or reduce the incidence of bullying, little remains known about what specific intervention strategies are most successful in reducing bullying in the school setting. Using the social-ecological framework, this paper examines school-based disciplinary interventions often used to deliver consequences to deter the reoccurrence of bullying and aggressive behaviors among school-aged children. Data for this study are drawn from the School-Wide Information System (SWIS) with the final analytic sample consisting of 1,221 students in grades K – 12 who received an office disciplinary referral for bullying during the first semester. Using Kaplan-Meier Failure Functions and Multi-level discrete time hazard models, determinants of the probability of a student receiving a second referral over time were examined. Of the seven interventions tested, only Parent-Teacher Conference (AOR=0.65, pbullying and aggressive behaviors. By using a social-ecological framework, schools can develop strategies that deter the reoccurrence of bullying by identifying key factors that enhance a sense of connection between the students’ mesosystems as well as utilizing disciplinary strategies that take into consideration student’s microsystem roles. PMID:22878779

  19. Examining Equity Sensitivity: An Investigation Using the Big Five and HEXACO Models of Personality (United States)

    Woodley, Hayden J. R.; Bourdage, Joshua S.; Ogunfowora, Babatunde; Nguyen, Brenda


    The construct of equity sensitivity describes an individual's preference about his/her desired input to outcome ratio. Individuals high on equity sensitivity tend to be more input oriented, and are often called “Benevolents.” Individuals low on equity sensitivity are more outcome oriented, and are described as “Entitleds.” Given that equity sensitivity has often been described as a trait, the purpose of the present study was to examine major personality correlates of equity sensitivity, so as to inform both the nature of equity sensitivity, and the potential processes through which certain broad personality traits may relate to outcomes. We examined the personality correlates of equity sensitivity across three studies (total N = 1170), two personality models (i.e., the Big Five and HEXACO), the two most common measures of equity sensitivity (i.e., the Equity Preference Questionnaire and Equity Sensitivity Inventory), and using both self and peer reports of personality (in Study 3). Although results varied somewhat across samples, the personality variables of Conscientiousness and Honesty-Humility, followed by Agreeableness, were the most robust predictors of equity sensitivity. Individuals higher on these traits were more likely to be Benevolents, whereas those lower on these traits were more likely to be Entitleds. Although some associations between Extraversion, Openness, and Neuroticism and equity sensitivity were observed, these were generally not robust. Overall, it appears that there are several prominent personality variables underlying equity sensitivity, and that the addition of the HEXACO model's dimension of Honesty-Humility substantially contributes to our understanding of equity sensitivity. PMID:26779102

  20. Genetic analyses using GGE model and a mixed linear model approach, and stability analyses using AMMI bi-plot for late-maturity alpha-amylase activity in bread wheat genotypes. (United States)

    Rasul, Golam; Glover, Karl D; Krishnan, Padmanaban G; Wu, Jixiang; Berzonsky, William A; Fofana, Bourlaye


    Low falling number and discounting grain when it is downgraded in class are the consequences of excessive late-maturity α-amylase activity (LMAA) in bread wheat (Triticum aestivum L.). Grain expressing high LMAA produces poorer quality bread products. To effectively breed for low LMAA, it is necessary to understand what genes control it and how they are expressed, particularly when genotypes are grown in different environments. In this study, an International Collection (IC) of 18 spring wheat genotypes and another set of 15 spring wheat cultivars adapted to South Dakota (SD), USA were assessed to characterize the genetic component of LMAA over 5 and 13 environments, respectively. The data were analysed using a GGE model with a mixed linear model approach and stability analysis was presented using an AMMI bi-plot on R software. All estimated variance components and their proportions to the total phenotypic variance were highly significant for both sets of genotypes, which were validated by the AMMI model analysis. Broad-sense heritability for LMAA was higher in SD adapted cultivars (53%) compared to that in IC (49%). Significant genetic effects and stability analyses showed some genotypes, e.g. 'Lancer', 'Chester' and 'LoSprout' from IC, and 'Alsen', 'Traverse' and 'Forefront' from SD cultivars could be used as parents to develop new cultivars expressing low levels of LMAA. Stability analysis using an AMMI bi-plot revealed that 'Chester', 'Lancer' and 'Advance' were the most stable across environments, while in contrast, 'Kinsman', 'Lerma52' and 'Traverse' exhibited the lowest stability for LMAA across environments.

  1. ATOP - The Advanced Taiwan Ocean Prediction System Based on the mpiPOM. Part 1: Model Descriptions, Analyses and Results

    Directory of Open Access Journals (Sweden)

    Leo Oey


    Full Text Available A data-assimilated Taiwan Ocean Prediction (ATOP system is being developed at the National Central University, Taiwan. The model simulates sea-surface height, three-dimensional currents, temperature and salinity and turbulent mixing. The model has options for tracer and particle-tracking algorithms, as well as for wave-induced Stokes drift and wave-enhanced mixing and bottom drag. Two different forecast domains have been tested: a large-grid domain that encompasses the entire North Pacific Ocean at 0.1° × 0.1° horizontal resolution and 41 vertical sigma levels, and a smaller western North Pacific domain which at present also has the same horizontal resolution. In both domains, 25-year spin-up runs from 1988 - 2011 were first conducted, forced by six-hourly Cross-Calibrated Multi-Platform (CCMP and NCEP reanalysis Global Forecast System (GSF winds. The results are then used as initial conditions to conduct ocean analyses from January 2012 through February 2012, when updated hindcasts and real-time forecasts begin using the GFS winds. This paper describes the ATOP system and compares the forecast results against satellite altimetry data for assessing model skills. The model results are also shown to compare well with observations of (i the Kuroshio intrusion in the northern South China Sea, and (ii subtropical counter current. Review and comparison with other models in the literature of ¡§(i¡¨ are also given.

  2. A regional tidal/subtidal circulation model of the southeastern Bering Sea: development, sensitivity analyses and hindcasting (United States)

    Hermann, Albert J.; Stabeno, Phyllis J.; Haidvogel, Dale B.; Musgrave, David L.


    A regional eddy-resolving primitive equation circulation model was used to simulate circulation on the southeastern Bering Sea (SEBS) shelf and basin. This model resolves the dominant observed mean currents, eddies and meanders in the region, and simultaneously includes both tidal and subtidal dynamics. Circulation, temperature, and salinity fields for years 1995 and 1997 were hindcast, using daily wind and buoyancy flux estimates, and tidal forcing derived from a global model. This paper describes the development of the regional model, a comparison of model results with available Eulerian and Lagrangian data, a comparison of results between the two hindcast years, and a sensitivity analysis. Based on these hindcasts and sensitivity analyses, we suggest the following: (1) The Bering Slope Current is a primary source of large ( ˜100 km diameter) eddies in the SEBS basin. Smaller meanders are also formed along the 100 m isobath on the southeastern shelf, and along the 200-m isobath near the shelf break. (2) There is substantial interannual variability in the statistics of eddies within the basin, driven by variability in the strength of the ANSC. (3) The mean flow on the shelf is not strongly sensitive to changes in the imposed strength of the ANSC; rather, it is strongly sensitive to the local wind forcing. (4) Vertical mixing in the SEBS is strongly affected by both tidal and subtidal dynamics. Strongest mixing in the SEBS may in fact occur between the 100- and 400-m isobaths, near the Pribilof Islands, and in Unimak Pass.

  3. One size does not fit all: On how Markov model order dictates performance of genomic sequence analyses (United States)

    Narlikar, Leelavati; Mehta, Nidhi; Galande, Sanjeev; Arjunwadkar, Mihir


    The structural simplicity and ability to capture serial correlations make Markov models a popular modeling choice in several genomic analyses, such as identification of motifs, genes and regulatory elements. A critical, yet relatively unexplored, issue is the determination of the order of the Markov model. Most biological applications use a predetermined order for all data sets indiscriminately. Here, we show the vast variation in the performance of such applications with the order. To identify the ‘optimal’ order, we investigated two model selection criteria: Akaike information criterion and Bayesian information criterion (BIC). The BIC optimal order delivers the best performance for mammalian phylogeny reconstruction and motif discovery. Importantly, this order is different from orders typically used by many tools, suggesting that a simple additional step determining this order can significantly improve results. Further, we describe a novel classification approach based on BIC optimal Markov models to predict functionality of tissue-specific promoters. Our classifier discriminates between promoters active across 12 different tissues with remarkable accuracy, yielding 3 times the precision expected by chance. Application to the metagenomics problem of identifying the taxum from a short DNA fragment yields accuracies at least as high as the more complex mainstream methodologies, while retaining conceptual and computational simplicity. PMID:23267010

  4. Advances in global sensitivity analyses of demographic-based species distribution models to address uncertainties in dynamic landscapes

    Directory of Open Access Journals (Sweden)

    Ilona Naujokaitis-Lewis


    Full Text Available Developing a rigorous understanding of multiple global threats to species persistence requires the use of integrated modeling methods that capture processes which influence species distributions. Species distribution models (SDMs coupled with population dynamics models can incorporate relationships between changing environments and demographics and are increasingly used to quantify relative extinction risks associated with climate and land-use changes. Despite their appeal, uncertainties associated with complex models can undermine their usefulness for advancing predictive ecology and informing conservation management decisions. We developed a computationally-efficient and freely available tool (GRIP 2.0 that implements and automates a global sensitivity analysis of coupled SDM-population dynamics models for comparing the relative influence of demographic parameters and habitat attributes on predicted extinction risk. Advances over previous global sensitivity analyses include the ability to vary habitat suitability across gradients, as well as habitat amount and configuration of spatially-explicit suitability maps of real and simulated landscapes. Using GRIP 2.0, we carried out a multi-model global sensitivity analysis of a coupled SDM-population dynamics model of whitebark pine (Pinus albicaulis in Mount Rainier National Park as a case study and quantified the relative influence of input parameters and their interactions on model predictions. Our results differed from the one-at-time analyses used in the original study, and we found that the most influential parameters included the total amount of suitable habitat within the landscape, survival rates, and effects of a prevalent disease, white pine blister rust. Strong interactions between habitat amount and survival rates of older trees suggests the importance of habitat in mediating the negative influences of white pine blister rust. Our results underscore the importance of considering habitat

  5. Data Assimilation Tools for CO2 Reservoir Model Development – A Review of Key Data Types, Analyses, and Selected Software

    Energy Technology Data Exchange (ETDEWEB)

    Rockhold, Mark L.; Sullivan, E. C.; Murray, Christopher J.; Last, George V.; Black, Gary D.


    Pacific Northwest National Laboratory (PNNL) has embarked on an initiative to develop world-class capabilities for performing experimental and computational analyses associated with geologic sequestration of carbon dioxide. The ultimate goal of this initiative is to provide science-based solutions for helping to mitigate the adverse effects of greenhouse gas emissions. This Laboratory-Directed Research and Development (LDRD) initiative currently has two primary focus areas—advanced experimental methods and computational analysis. The experimental methods focus area involves the development of new experimental capabilities, supported in part by the U.S. Department of Energy’s (DOE) Environmental Molecular Science Laboratory (EMSL) housed at PNNL, for quantifying mineral reaction kinetics with CO2 under high temperature and pressure (supercritical) conditions. The computational analysis focus area involves numerical simulation of coupled, multi-scale processes associated with CO2 sequestration in geologic media, and the development of software to facilitate building and parameterizing conceptual and numerical models of subsurface reservoirs that represent geologic repositories for injected CO2. This report describes work in support of the computational analysis focus area. The computational analysis focus area currently consists of several collaborative research projects. These are all geared towards the development and application of conceptual and numerical models for geologic sequestration of CO2. The software being developed for this focus area is referred to as the Geologic Sequestration Software Suite or GS3. A wiki-based software framework is being developed to support GS3. This report summarizes work performed in FY09 on one of the LDRD projects in the computational analysis focus area. The title of this project is Data Assimilation Tools for CO2 Reservoir Model Development. Some key objectives of this project in FY09 were to assess the current state

  6. Respiratory flows during early childhood: Computational models to examine therapeutic aerosols in the developing airways (United States)

    Tenenbaum-Katan, Janna; Hofemeier, Philipp; Sznitman, Josué; Janna Tenenbaum-Katan Team


    Inhalation therapy is the cornerstone of early-childhood respiratory treatments, as well as a rising potential for systemic drug delivery and pulmonary vaccination. As such, indispensable understanding of respiratory flow phenomena, coupled with particle transport at the deep regions of children's lungs is necessary to attain efficient targeting of aerosol therapy. However, fundamental research of pulmonary transport is overwhelmingly focused on adults. In our study, we have developed an anatomically-inspired computational model of representing pulmonary acinar regions at several age points during a child's development. Our numerical simulations examine respiratory flows and particle deposition maps within the acinar model, accounting for varying age dependant anatomical considerations and ventilation patterns. Resulting deposition maps of aerosols alter with age, such findings might suggest that medication protocols of inhalation therapy in young children should be considered to be accordingly amended with the child's development. Additionally to understanding basic scientific concepts of age effects on aerosol deposition, our research can potentially contribute practical guidelines to therapy protocols, and its' necessary modifications with age. We acknowledge the support of the ISF and the Israeli ministry of Science.

  7. Aerosol penetration of leak pathways : an examination of the available data and models.

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Dana Auburn


    Data and models of aerosol particle deposition in leak pathways are described. Pathways considered include capillaries, orifices, slots and cracks in concrete. The Morewitz-Vaughan criterion for aerosol plugging of leak pathways is shown to be applicable only to a limited range of particle settling velocities and Stokes numbers. More useful are sampling efficiency criteria defined by Davies and by Liu and Agarwal. Deposition of particles can be limited by bounce from surfaces defining leak pathways and by resuspension of particles deposited on these surfaces. A model of the probability of particle bounce is described. Resuspension of deposited particles can be triggered by changes in flow conditions, particle impact on deposits and by shock or vibration of the surfaces. This examination was performed as part of the review of the AP1000 Standard Combined License Technical Report, APP-GW-GLN-12, Revision 0, 'Offsite and Control Room Dose Changes' (TR-112) in support of the USNRC AP1000 Standard Combined License Pre-Application Review.

  8. Perspectives: Using Results from HRSA's Health Workforce Simulation Model to Examine the Geography of Primary Care. (United States)

    Streeter, Robin A; Zangaro, George A; Chattopadhyay, Arpita


    Inform health planning and policy discussions by describing Health Resources and Services Administration's (HRSA's) Health Workforce Simulation Model (HWSM) and examining the HWSM's 2025 supply and demand projections for primary care physicians, nurse practitioners (NPs), and physician assistants (PAs). HRSA's recently published projections for primary care providers derive from an integrated microsimulation model that estimates health workforce supply and demand at national, regional, and state levels. Thirty-seven states are projected to have shortages of primary care physicians in 2025, and nine states are projected to have shortages of both primary care physicians and PAs. While no state is projected to have a 2025 shortage of primary care NPs, many states are expected to have only a small surplus. Primary care physician shortages are projected for all parts of the United States, while primary care PA shortages are generally confined to Midwestern and Southern states. No state is projected to have shortages of all three provider types. Projected shortages must be considered in the context of baseline assumptions regarding current supply, demand, provider-service ratios, and other factors. Still, these findings suggest geographies with possible primary care workforce shortages in 2025 and offer opportunities for targeting efforts to enhance workforce flexibility. © Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  9. Longitudinal Examination of Resilience After Traumatic Brain Injury: A Traumatic Brain Injury Model Systems Study. (United States)

    Marwitz, Jennifer H; Sima, Adam P; Kreutzer, Jeffrey S; Dreer, Laura E; Bergquist, Thomas F; Zafonte, Ross; Johnson-Greene, Douglas; Felix, Elizabeth R


    To evaluate (1) the trajectory of resilience during the first year after a moderate-severe traumatic brain injury (TBI); (2) factors associated with resilience at 3, 6, and 12 months postinjury; and (3) changing relationships over time between resilience and other factors. Longitudinal analysis of an observational cohort. Five inpatient rehabilitation centers. Patients with TBI (N=195) enrolled in the resilience module of the TBI Model Systems study with data collected at 3-, 6-, and 12-month follow-up. Not applicable. Connor-Davidson Resilience Scale. Initially, resilience levels appeared to be stable during the first year postinjury. Individual growth curve models were used to examine resilience over time in relation to demographic, psychosocial, and injury characteristics. After adjusting for these characteristics, resilience actually declined over time. Higher levels of resilience were related to nonminority status, absence of preinjury substance abuse, lower anxiety and disability level, and greater life satisfaction. Resilience is a construct that is relevant to understanding brain injury outcomes and has potential value in planning clinical interventions. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  10. Using Simpson’s diversity index to examine multidimensional models of diversity in health professions education (United States)

    McLaughlin, Gerald W.; McLaughlin, Josetta S.; White, Carla Y.


    Objectives This study explored new models of diversity for health professions education that incorporate multiple attributes and examined differences in diversity based on urbanicity, geographic region, and institutional structure. Methods Simpson’s Diversity Index was used to develop race, gender, and interprofessional diversity indices for health professions schools in the United States (N = 318). Sullivan’s extension was used to develop a composite diversity index that incorporated multiple individual attributes for each school. Pearson’s r was used to investigate correlations between continuous variables. ANOVA and independent t-tests were used to compare groups based on urbanicity, geographic region, and Basic Carnegie Classification. Results Mean (SD) for race, gender, and interprofessional  diversity indices were 0.36(0.17), 0.45(0.07), and 0.22(0.27) respectively. All correlations between the three indices were weak. The composite diversity index for this sample was 0.34(0.13). Significant differences in diversity were found between institutions based on urbanicity, Basic Carnegie Classification, and geographic region. Conclusions Multidimensional models provide support for expanding measures of diversity to include multiple characteristics and attributes. The approach demonstrated in this study enables institutions to complement and extend traditional measures of diversity as a means of providing evidence for decision-making and progress towards institutional initiatives. PMID:26724917

  11. Modeling von Karman vortex shedding in cylinder wake to examine energetic coherent motions on hydrokinetic turbines (United States)

    Neary, V. S.; Gunawan, B.; Chamorro, L. P.; Stekovic, S.; Hill, C.


    Numerous investigators have examined vortex-shedding in the wake of cylinders. This is a classical flow problem that has many engineering applications, including pronounced flow disturbance, turbulence generation, and sediment scour in the wakes of in stream structures, e.g. bridge piers and towers for marine and hydrokinetic (MHK) turbines. It is also important to understand the contribution of large coherent motions on the unsteady loading and performance of hydrokinetic turbines. Unsteady vortex shedding is caused by flow separation and detachment within the near-wall region along the cylinder surface. Our aim is to examine the unsteady flow field and von Karman vortex shedding resulting from unsteady turbulent flow around an emergent cylinder mounted perpendicular to a fixed surface by conducting physical and numerical modeling experiments. The numerical simulation emulates an open-channel flow experiment at the St. Anthony Falls Laboratory at the University of Minnesota, where instantaneous velocity was measured using three synchronized acoustic Doppler velocimeters (ADVs). The open-channel flume is 80 m long, and 2.75 m wide. The flow depth is 1.15 m. The cylinder diameter is 0.116 m. The flow is turbulent, with a cylinder Reynolds number equal to 5.44E4. We use the commercial CFD software, STAR-CCM+, to generate the computational mesh that models the flow geometry around the cylinder, and to numerically solve the unsteady Reynolds-Averaged Navier-Stokes (URANS) equations. The generated mesh is fine enough (> 2 million elements) to resolve the coherent structures of vortex shedding. The Frost high-performance cluster (an ORNL supercomputer) is used to run the simulation. The results show how a validated CFD model can be used to design the layout and spacing of synchronized ADV point measurements to characterize essential features of the Karman shedding in the cylinder wake. A similar approach can be used to design field ADV arrays for measuring more complex

  12. An examination of sources of sensitivity of consumer surplus estimates in travel cost models. (United States)

    Blaine, Thomas W; Lichtkoppler, Frank R; Bader, Timothy J; Hartman, Travis J; Lucente, Joseph E


    We examine sensitivity of estimates of recreation demand using the Travel Cost Method (TCM) to four factors. Three of the four have been routinely and widely discussed in the TCM literature: a) Poisson verses negative binomial regression; b) application of Englin correction to account for endogenous stratification; c) truncation of the data set to eliminate outliers. A fourth issue we address has not been widely modeled: the potential effect on recreation demand of the interaction between income and travel cost. We provide a straightforward comparison of all four factors, analyzing the impact of each on regression parameters and consumer surplus estimates. Truncation has a modest effect on estimates obtained from the Poisson models but a radical effect on the estimates obtained by way of the negative binomial. Inclusion of an income-travel cost interaction term generally produces a more conservative but not a statistically significantly different estimate of consumer surplus in both Poisson and negative binomial models. It also generates broader confidence intervals. Application of truncation, the Englin correction and the income-travel cost interaction produced the most conservative estimates of consumer surplus and eliminated the statistical difference between the Poisson and the negative binomial. Use of the income-travel cost interaction term reveals that for visitors who face relatively low travel costs, the relationship between income and travel demand is negative, while it is positive for those who face high travel costs. This provides an explanation of the ambiguities on the findings regarding the role of income widely observed in the TCM literature. Our results suggest that policies that reduce access to publicly owned resources inordinately impact local low income recreationists and are contrary to environmental justice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. A critical examination of the youth foyer model for alleviating homelessness: Strengthening a promising evidence base

    Directory of Open Access Journals (Sweden)

    Iris Levin


    Full Text Available This article assesses the quality of 15 primary studies that examined the effectiveness of youth foyer or foyer-like programs on the lives of young homeless people. The youth foyer model provides an integrated approach to tackling youth homelessness, connecting affordable accommodation to training and employment. In Australia, there is growing support from government for the development and funding of foyer programs. However to date, there has been very limited development and investment in the evidence base on the effectiveness of this model in Australia or internationally. Following an extensive literature search, we argue that there is a need to lift the standard of the evidence base of youth foyer effectiveness. We discuss two main issues: the difficulty studies had validating claims of foyer effectiveness, and limitations of research design and methodology. The implications of the lack of rigour in the research reviewed are three-fold. Firstly, youth foyer evaluation study quality could be improved by: clearer methodological and model documentation; post intervention follow-up design; comparison of data to non-randomised comparison groups; and a pre-publication peer-review process. This would be supported with clearer expectations from the research community regarding the production and assessment of grey literature. Secondly, while the standard of reporting needs to be raised, the ‘gold standard’ (i.e. randomised controlled trials of research design in the scientific community is not a relevant benchmark in the field of homelessness research. This is due to the complexity of homelessness interventions and the inadequate funding of the homelessness research field. Greater investment in robust research and evaluation should accompany the substantial investment in youth foyer programs in order to accurately appraise the effectiveness of the youth foyer model. Thirdly, the lack of rigour in the studies reviewed suggests gaps in the service

  14. Using plant growth modeling to analyse C source-sink relations under drought: inter and intra specific comparison

    Directory of Open Access Journals (Sweden)

    Benoit ePallas


    Full Text Available The ability to assimilate C and allocate NSC (non structural carbohydrates to the most appropriate organs is crucial to maximize plant ecological or agronomic performance. Such C source and sink activities are differentially affected by environmental constraints. Under drought, plant growth is generally more sink than source limited as organ expansion or appearance rate is earlier and stronger affected than C assimilation. This favors plant survival and recovery but not always agronomic performance as NSC are stored rather than used for growth due to a modified metabolism in source and sink leaves. Such interactions between plant C and water balance are complex and plant modeling can help analyzing their impact on plant phenotype. This paper addresses the impact of trade-offs between C sink and source activities and plant production under drought, combining experimental and modeling approaches. Two contrasted monocotyledonous species (rice, oil palm were studied. Experimentally, the sink limitation of plant growth under moderate drought was confirmed as well as the modifications in NSC metabolism in source and sink organs. Under severe stress, when C source became limiting, plant NSC concentration decreased. Two plant models dedicated to oil palm and rice morphogenesis were used to perform a sensitivity analysis and further explore how to optimize C sink and source drought sensitivity to maximize plant growth. Modeling results highlighted that optimal drought sensitivity depends both on drought type and species and that modeling is a great opportunity to analyse such complex processes. Further modeling needs and more generally the challenge of using models to support complex trait breeding are discussed.

  15. Comparative sequence and structural analyses of G-protein-coupled receptor crystal structures and implications for molecular models.

    Directory of Open Access Journals (Sweden)

    Catherine L Worth

    Full Text Available BACKGROUND: Up until recently the only available experimental (high resolution structure of a G-protein-coupled receptor (GPCR was that of bovine rhodopsin. In the past few years the determination of GPCR structures has accelerated with three new receptors, as well as squid rhodopsin, being successfully crystallized. All share a common molecular architecture of seven transmembrane helices and can therefore serve as templates for building molecular models of homologous GPCRs. However, despite the common general architecture of these structures key differences do exist between them. The choice of which experimental GPCR structure(s to use for building a comparative model of a particular GPCR is unclear and without detailed structural and sequence analyses, could be arbitrary. The aim of this study is therefore to perform a systematic and detailed analysis of sequence-structure relationships of known GPCR structures. METHODOLOGY: We analyzed in detail conserved and unique sequence motifs and structural features in experimentally-determined GPCR structures. Deeper insight into specific and important structural features of GPCRs as well as valuable information for template selection has been gained. Using key features a workflow has been formulated for identifying the most appropriate template(s for building homology models of GPCRs of unknown structure. This workflow was applied to a set of 14 human family A GPCRs suggesting for each the most appropriate template(s for building a comparative molecular model. CONCLUSIONS: The available crystal structures represent only a subset of all possible structural variation in family A GPCRs. Some GPCRs have structural features that are distributed over different crystal structures or which are not present in the templates suggesting that homology models should be built using multiple templates. This study provides a systematic analysis of GPCR crystal structures and a consistent method for identifying

  16. Comparative sequence and structural analyses of G-protein-coupled receptor crystal structures and implications for molecular models. (United States)

    Worth, Catherine L; Kleinau, Gunnar; Krause, Gerd


    Up until recently the only available experimental (high resolution) structure of a G-protein-coupled receptor (GPCR) was that of bovine rhodopsin. In the past few years the determination of GPCR structures has accelerated with three new receptors, as well as squid rhodopsin, being successfully crystallized. All share a common molecular architecture of seven transmembrane helices and can therefore serve as templates for building molecular models of homologous GPCRs. However, despite the common general architecture of these structures key differences do exist between them. The choice of which experimental GPCR structure(s) to use for building a comparative model of a particular GPCR is unclear and without detailed structural and sequence analyses, could be arbitrary. The aim of this study is therefore to perform a systematic and detailed analysis of sequence-structure relationships of known GPCR structures. We analyzed in detail conserved and unique sequence motifs and structural features in experimentally-determined GPCR structures. Deeper insight into specific and important structural features of GPCRs as well as valuable information for template selection has been gained. Using key features a workflow has been formulated for identifying the most appropriate template(s) for building homology models of GPCRs of unknown structure. This workflow was applied to a set of 14 human family A GPCRs suggesting for each the most appropriate template(s) for building a comparative molecular model. The available crystal structures represent only a subset of all possible structural variation in family A GPCRs. Some GPCRs have structural features that are distributed over different crystal structures or which are not present in the templates suggesting that homology models should be built using multiple templates. This study provides a systematic analysis of GPCR crystal structures and a consistent method for identifying suitable templates for GPCR homology modelling that will

  17. Static and free-vibration analyses of dental prosthesis and atherosclerotic human artery by refined finite element models. (United States)

    Carrera, E; Guarnera, D; Pagani, A


    Static and modal responses of representative biomechanical structures are investigated in this paper by employing higher-order theories of structures and finite element approximations. Refined models are implemented in the domain of the Carrera unified formulation (CUF), according to which low- to high-order kinematics can be postulated as arbitrary and, eventually, hierarchical expansions of the generalized displacement unknowns. By using CUF along with the principle of virtual work, the governing equations are expressed in terms of fundamental nuclei of finite element arrays. The fundamental nuclei are invariant of the theory approximation order and can be opportunely employed to implement variable kinematics theories of bio-structures. In this work, static and free-vibration analyses of an atherosclerotic plaque of a human artery and a dental prosthesis are discussed. The results from the proposed methodologies highlight a number of advantages of CUF models with respect to already established theories and commercial software tools. Namely, (i) CUF models can represent correctly the higher-order phenomena related to complex stress/strain field distributions and coupled mode shapes; (ii) bio-structures can be modeled in a component-wise sense by only employing the physical boundaries of the problem domain and without making any geometrical simplification. This latter aspect, in particular, can be currently accomplished only by using three-dimensional analysis, which may be computationally unbearable as complex bio-systems are considered.

  18. A multinomial logit model-Bayesian network hybrid approach for driver injury severity analyses in rear-end crashes. (United States)

    Chen, Cong; Zhang, Guohui; Tarefder, Rafiqul; Ma, Jianming; Wei, Heng; Guan, Hongzhi


    Rear-end crash is one of the most common types of traffic crashes in the U.S. A good understanding of its characteristics and contributing factors is of practical importance. Previously, both multinomial Logit models and Bayesian network methods have been used in crash modeling and analysis, respectively, although each of them has its own application restrictions and limitations. In this study, a hybrid approach is developed to combine multinomial logit models and Bayesian network methods for comprehensively analyzing driver injury severities in rear-end crashes based on state-wide crash data collected in New Mexico from 2010 to 2011. A multinomial logit model is developed to investigate and identify significant contributing factors for rear-end crash driver injury severities classified into three categories: no injury, injury, and fatality. Then, the identified significant factors are utilized to establish a Bayesian network to explicitly formulate statistical associations between injury severity outcomes and explanatory attributes, including driver behavior, demographic features, vehicle factors, geometric and environmental characteristics, etc. The test results demonstrate that the proposed hybrid approach performs reasonably well. The Bayesian network reference analyses indicate that the factors including truck-involvement, inferior lighting conditions, windy weather conditions, the number of vehicles involved, etc. could significantly increase driver injury severities in rear-end crashes. The developed methodology and estimation results provide insights for developing effective countermeasures to reduce rear-end crash injury severities and improve traffic system safety performance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Comparative analyses reveal potential uses of Brachypodium distachyon as a model for cold stress responses in temperate grasses

    Directory of Open Access Journals (Sweden)

    Li Chuan


    Full Text Available Abstract Background Little is known about the potential of Brachypodium distachyon as a model for low temperature stress responses in Pooideae. The ice recrystallization inhibition protein (IRIP genes, fructosyltransferase (FST genes, and many C-repeat binding factor (CBF genes are Pooideae specific and important in low temperature responses. Here we used comparative analyses to study conservation and evolution of these gene families in B. distachyon to better understand its potential as a model species for agriculturally important temperate grasses. Results Brachypodium distachyon contains cold responsive IRIP genes which have evolved through Brachypodium specific gene family expansions. A large cold responsive CBF3 subfamily was identified in B. distachyon, while CBF4 homologs are absent from the genome. No B. distachyon FST gene homologs encode typical core Pooideae FST-motifs and low temperature induced fructan accumulation was dramatically different in B. distachyon compared to core Pooideae species. Conclusions We conclude that B. distachyon can serve as an interesting model for specific molecular mechanisms involved in low temperature responses in core Pooideae species. However, the evolutionary history of key genes involved in low temperature responses has been different in Brachypodium and core Pooideae species. These differences limit the use of B. distachyon as a model for holistic studies relevant for agricultural core Pooideae species.

  20. Contribution of JMA to the WMO Technical Task Team on meteorological analyses for Fukushima Daiichi Nuclear Power Plant accident and relevant atmospheric transport modeling at MRI

    International Nuclear Information System (INIS)

    Saito, Kazuo; Shimbori, Toshiki; Kato, Teruyuki; Kajino, Mizuo; Sekiyama, Tsuyoshi T.; Tanaka, Taichu Y.; Maki, Takashi; Draxler, Roland; Hara, Tabito; Toyoda, Eizi; Honda, Yuki; Nagata, Kazuhiko; Fujita, Tsukasa; Sakamoto, Masami; Terada, Hiroaki; Chino, Masamichi


    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was asked to produce a scientific report for the General Assembly on the levels and effects of radiation exposure caused by the accident at the Fukushima Daiichi Nuclear Power Plant, and UNSCEAR requested the World Meteorological Organization (WMO) to develop a set of meteorological analyses for assessing the atmospheric transport, dispersion, and deposition of radioactive materials. In response to UNSCEAR's request, the WMO's Commission for Basic Systems convened a technical task team of experts from five countries (Austria, Canada, Japan, United Kingdom, and the United States) in November 2011. The primary aim of this team was to examine how the use of meteorological analyses could improve atmospheric transport, dispersion, and deposition model (ATDM) calculations. As the Regional Specialized Meteorological Center of the country in which the accident occurred, the Japan Meteorological Agency (JMA) collaborated with the WMO Task Team by providing its mesoscale analysis based on operational four-dimensional variational data assimilation and radar/rain gauge-analyzed precipitation (RAP) data in the standard WMO format (GRIB2). To evaluate the quality of the meteorological analyses, the WMO Task Team conducted test simulations with their regional ATDMs and different meteorological analyses. JMA developed a regional ATDM for radionuclides by modifying its operational regional atmospheric transport model, which had been previously used for photochemical oxidant predictions and volcanic ashfall forecasts. The modified model (hereafter referred to as JMA-RATM) newly implemented dry deposition, wet scavenging, and gravitational settling of radionuclide aerosol particles. The preliminary and revised calculations of JMA-RATM were conducted with a horizontal concentration and deposition grid resolution of 5 km and a unit source emission rate, in accordance with the Task Team

  1. Assessing models of speciation under different biogeographic scenarios; An empirical study using multi-locus and RNA-seq analyses (United States)

    Edwards, Taylor; Tollis, Marc; Hsieh, PingHsun; Gutenkunst, Ryan N.; Liu, Zhen; Kusumi, Kenro; Culver, Melanie; Murphy, Robert W.


    Evolutionary biology often seeks to decipher the drivers of speciation, and much debate persists over the relative importance of isolation and gene flow in the formation of new species. Genetic studies of closely related species can assess if gene flow was present during speciation, because signatures of past introgression often persist in the genome. We test hypotheses on which mechanisms of speciation drove diversity among three distinct lineages of desert tortoise in the genus Gopherus. These lineages offer a powerful system to study speciation, because different biogeographic patterns (physical vs. ecological segregation) are observed at opposing ends of their distributions. We use 82 samples collected from 38 sites, representing the entire species' distribution and generate sequence data for mtDNA and four nuclear loci. A multilocus phylogenetic analysis in *BEAST estimates the species tree. RNA-seq data yield 20,126 synonymous variants from 7665 contigs from two individuals of each of the three lineages. Analyses of these data using the demographic inference package ∂a∂i serve to test the null hypothesis of no gene flow during divergence. The best-fit demographic model for the three taxa is concordant with the *BEAST species tree, and the ∂a∂i analysis does not indicate gene flow among any of the three lineages during their divergence. These analyses suggest that divergence among the lineages occurred in the absence of gene flow and in this scenario the genetic signature of ecological isolation (parapatric model) cannot be differentiated from geographic isolation (allopatric model).

  2. Examining a comprehensive model of disaster-related posttraumatic stress disorder in systematically studied survivors of 10 disasters. (United States)

    North, Carol S; Oliver, Julianne; Pandya, Anand


    Using a comprehensive disaster model, we examined predictors of posttraumatic stress disorder (PTSD) in combined data from 10 different disasters. The combined sample included data from 811 directly exposed survivors of 10 disasters between 1987 and 1995. We used consistent methods across all 10 disaster samples, including full diagnostic assessment. In multivariate analyses, predictors of PTSD were female gender, younger age, Hispanic ethnicity, less education, ever-married status, predisaster psychopathology, disaster injury, and witnessing injury or death; exposure through death or injury to friends or family members and witnessing the disaster aftermath did not confer additional PTSD risk. Intentionally caused disasters associated with PTSD in bivariate analysis did not independently predict PTSD in multivariate analysis. Avoidance and numbing symptoms represented a PTSD marker. Despite confirming some previous research findings, we found no associations between PTSD and disaster typology. Prospective research is needed to determine whether early avoidance and numbing symptoms identify individuals likely to develop PTSD later. Our findings may help identify at-risk populations for treatment research.

  3. A test of the Olson Circumplex Model: examining its curvilinear assumption and the presence of extreme types. (United States)

    Anderson, S A; Gavazzi, S M


    The debate over the usefulness of different family models continues. Recent attention has been paid to comparisons between the Olson Circumplex Model and the Beavers Systems Model. The present study seeks to contribute evidence that bears directly upon one of the most fundamental points of controversy surrounding the Olson model--the linear versus curvilinear nature of the cohesion and adaptability dimensions. A further contribution is an examination of the actual occurrence of the Circumplex Model's extreme types in a clinical population.


    Directory of Open Access Journals (Sweden)

    Wahyu Bahari Setianto


    Full Text Available Application of  supercritical carbon dioxide (SC-CO2 to vegetable oil extraction became an attractive technique due to its high solubility, short extraction time and simple purification. The method is considered as earth friendly technology due to the absence of chemical usage. Solubility of solute-SC-CO2 is an important data for application of the SC-CO2 extraction. In this work, the equilibrium solubility of the palm kernel oil (PKO in SC-CO2 has been examined using extraction curve analysis. The examinations were performed at temperature and pressure ranges of  323.15 K to 353.15 K and 20.7 to 34.5 MPa respectively. It was obtained that the experimental solubility were from 0.0160 to 0.0503 g oil/g CO2 depend on the extraction condition. The experimental solubility data was well correlated with a solvent density based model with absolute percent deviation of 0.96. PENENTUAN KELARUTAN MINYAK INTI KELAPA SAWIT DAN PEMODELAN EKSTRAKSI DENGAN KARBON DIOKSIDA SUPERKRITIK. Sehubungan dengan kelarutan yang tinggi, waktu ekstraksi yang pendek dan pemurnian hasil yang mudah, aplikasi karbon dioksida superkritis (SC-CO2 pada ekstraksi minyak nabati menjadi sebuah teknik ekstraksi yang menarik. Karena tanpa penggunaan bahan kimia, metode ekstraksi ini dianggap sebagai teknologi yang ramah lingkungan. Kelarutan zat terlarut pada SC-CO2 merupakan data yang penting dalam aplikasi SC-CO2 pada proses ekstraksi.  Pada penelitian ini,  kelarutan kesetimbangan dari minyak biji sawit (PKO dalam SC-CO2 telah diuji dengan mengunakan analisa kurva proses ekstraksi. Pengujian kelarutan tersebut dilakukan pada rentang suhu 323,15 K sampai 353,15 K dan rentang tekanan 20,7 MPa sampai 34,5 MPa. Hasil analisa menunjukkan bahwa kelarutan kesetimbangan hasil percobaan  PKO pada SC-CO2 adalah 0.0160 g minyak/g CO2 sampai 0,0503 g minyak/g CO2 tergantung pada kondisi ekstraksi. Data kelarutan kesetimbangan hasil percobaan  telah dikorelasaikan dengan baik menggunakan

  5. Systems genetics of obesity in an F2 pig model by genome-wide association, genetic network and pathway analyses

    Directory of Open Access Journals (Sweden)

    Lisette J. A. Kogelman


    Full Text Available Obesity is a complex condition with world-wide exponentially rising prevalence rates, linked with severe diseases like Type 2 Diabetes. Economic and welfare consequences have led to a raised interest in a better understanding of the biological and genetic background. To date, whole genome investigations focusing on single genetic variants have achieved limited success, and the importance of including genetic interactions is becoming evident. Here, the aim was to perform an integrative genomic analysis in an F2 pig resource population that was constructed with an aim to maximize genetic variation of obesity-related phenotypes and genotyped using the 60K SNP chip. Firstly, Genome Wide Association (GWA analysis was performed on the Obesity Index to locate candidate genomic regions that were further validated using combined Linkage Disequilibrium Linkage Analysis and investigated by evaluation of haplotype blocks. We built Weighted Interaction SNP Hub (WISH and differentially wired (DW networks using genotypic correlations amongst obesity-associated SNPs resulting from GWA analysis. GWA results and SNP modules detected by WISH and DW analyses were further investigated by functional enrichment analyses. The functional annotation of SNPs revealed several genes associated with obesity, e.g. NPC2 and OR4D10. Moreover, gene enrichment analyses identified several significantly associated pathways, over and above the GWA study results, that may influence obesity and obesity related diseases, e.g. metabolic processes. WISH networks based on genotypic correlations allowed further identification of various gene ontology terms and pathways related to obesity and related traits, which were not identified by the GWA study. In conclusion, this is the first study to develop a (genetic obesity index and employ systems genetics in a porcine model to provide important insights into the complex genetic architecture associated with obesity and many biological pathways

  6. Examination of a cognitive model of stress, burnout, and intention to resign for Japanese nurses. (United States)

    Ohue, Takashi; Moriyama, Michiko; Nakaya, Takashi


    A reduction in burnout is required to decrease the voluntary turnover of nurses. This study was carried out with the aim of establishing a cognitive model of stress, burnout, and intention to resign for nurses. A questionnaire survey was administered to 336 nurses (27 male and 309 female) who had worked for ≤5 years at a hospital with multiple departments. The survey included an evaluation of burnout (Maslach Burnout Inventory), stress (Nursing Job Stressor Scale), automatic thoughts (Automatic Thoughts Questionnaire-Revised), and irrational beliefs (Japanese Irrational Belief Test), in addition to the intention to resign. The stressors that affected burnout in the nurses included conflict with other nursing staff, nursing role conflict, qualitative workload, quantitative workload, and conflict with patients. The irrational beliefs that were related to burnout included dependence, problem avoidance, and helplessness. In order to examine the automatic thoughts affecting burnout, groups with low and high negative automatic thoughts and low and high positive automatic thoughts were established. A two-way ANOVA showed a significant interaction of these factors with emotional exhaustion, but no significant interaction with depersonalization and a personal sense of accomplishment. Only the major effect was significant. The final model showed a process of "stressor → irrational beliefs → negative automatic thoughts/positive automatic thoughts → burnout". In addition, a relationship between burnout and an intention to resign was shown. These results suggest that stress and burnout in nurses might be prevented and that the number of nurses who leave their position could be decreased by changing irrational beliefs to rational beliefs, decreasing negative automatic thoughts, and facilitating positive automatic thoughts. © 2010 The Authors. Japan Journal of Nursing Science © 2010 Japan Academy of Nursing Science.

  7. Clustering structures of large proteins using multifractal analyses based on a 6-letter model and hydrophobicity scale of amino acids

    International Nuclear Information System (INIS)

    Yang Jianyi; Yu Zuguo; Anh, Vo


    The Schneider and Wrede hydrophobicity scale of amino acids and the 6-letter model of protein are proposed to study the relationship between the primary structure and the secondary structural classification of proteins. Two kinds of multifractal analyses are performed on the two measures obtained from these two kinds of data on large proteins. Nine parameters from the multifractal analyses are considered to construct the parameter spaces. Each protein is represented by one point in these spaces. A procedure is proposed to separate large proteins in the α, β, α + β and α/β structural classes in these parameter spaces. Fisher's linear discriminant algorithm is used to assess our clustering accuracy on the 49 selected large proteins. Numerical results indicate that the discriminant accuracies are satisfactory. In particular, they reach 100.00% and 84.21% in separating the α proteins from the {β, α + β, α/β} proteins in a parameter space; 92.86% and 86.96% in separating the β proteins from the {α + β, α/β} proteins in another parameter space; 91.67% and 83.33% in separating the α/β proteins from the α + β proteins in the last parameter space.

  8. Longitudinal examination of the exercise and self-esteem model in middle-aged women. (United States)

    Elavsky, Steriani


    This 2-year prospective study examined the exercise and self-esteem model in middle-aged women (N = 143) previously enrolled in a randomized controlled exercise trial. Across the 2-year period, increases in physical activity (PA) and self-efficacy and reductions in body mass index (BMI) were associated with improved subdomain self-perceptions relative to physical condition, and reductions in BMI were associated with improved subdomain self-perceptions relative to physical condition and body attractiveness. The effects of PA, self-efficacy, and BMI on changes in physical self-worth and global self-esteem were mediated by changes in self-perceptions relative to physical condition and body attractiveness. The results of this longitudinal analysis support the hierarchical and multidimensional structure of self-esteem and indicate that middle-aged women can enhance how they perceive their condition and body attractiveness by continued participation in physical activity, increasing their self-efficacy, and maintaining healthy BMI levels.

  9. A model-based examination of multivariate physical modes in the Gulf of Alaska (United States)

    Hermann, A. J.; Ladd, C.; Cheng, W.; Curchitser, E. N.; Hedstrom, K.


    We use multivariate output from a hydrodynamic model of the Gulf of Alaska (GOA) to explore the covariance among its physical state and air/sea fluxes. We attempt to summarize this coupled variability using a limited set of patterns, and examine their correlation to three large-scale climate indices relevant to the Northeast Pacific. This analysis is focused on perturbations from monthly climatology of the following attributes of the GOA: sea surface temperature, sea surface height, mixed layer depth, sea surface salinity, latent heat flux, sensible heat flux, shortwave irradiance, net long wave irradiance, currents at 40 m depth, and wind stress. We identified two multivariate modes, both substantially correlated with the Pacific Decadal Oscillation (PDO) and Multivariate El Nino (MEI) indices on interannual timescales, which together account for 30% of the total normalized variance of the perturbation time series. These two modes indicate the following covarying events during periods of positive PDO/MEI: (1) anomalously warm, wet and windy conditions (typically in winter), with elevated coastal SSH, followed 2-5 months later by (2) reduced cloud cover, with emerging shelf-break eddies. Similar modes are found when the analysis is performed separately on the eastern and western GOA; in general, modal amplitudes appear stronger in the western GOA.

  10. Civil engineering: EDF needs for concrete modelling; Genie civile: analyse des besoins EDF en modelisation du comportement des betons

    Energy Technology Data Exchange (ETDEWEB)

    Didry, O.; Gerard, B.; Bui, D. [Electricite de France (EDF), Direction des Etudes et Recherches, 92 - Clamart (France)


    Concrete structures which are encountered at EDF, like all civil engineering structures, age. In order to adapt the maintenance conditions of these structures, particularly to extend their service life, and also to prepare constructions of future structures, tools for predicting the behaviour of these structures in their environment should be available. For EDF the technical risks are high and consequently very appropriate R and D actions are required. In this context the Direction des Etudes et Recherches (DER) has developed a methodology for analysing concrete structure behaviour modelling. This approach has several aims: - making a distinction between the problems which refer to the existing models and those which require R and D; - displaying disciplinary links between different problems encountered on EDF structures (non-linear mechanical, chemical - hydraulic - mechanical coupling, etc); - listing of the existing tools and positioning the DER `Aster` finite element code among them. This document is a state of the art of scientific knowledge intended to shed light on the fields in which one should be involved when there is, on one part a strong requirement on the side of structure operators, and on the other one, the present tools do not allow this requirement to be satisfactorily met. The analysis has been done on 12 scientific subjects: 1) Hydration of concrete at early ages: exothermicity, hardening, autogenous shrinkage; 2) Drying and drying shrinkage; 3) Alkali-silica reaction and bulky stage formation; 4) Long term deterioration by leaching; 5) Ionic diffusion and associated attacks: the chlorides case; 6) Permeability / tightness of concrete; 7) Concretes -nonlinear behaviour and cracking (I): contribution of the plasticity models; 8) Concretes - nonlinear behaviour and cracking (II): contribution of the damage models; 9) Concretes - nonlinear behaviour and cracking (III): the contribution of the probabilistic analysis model; 10) Delayed behaviour of

  11. A permutation test to analyse systematic bias and random measurement errors of medical devices via boosting location and scale models. (United States)

    Mayr, Andreas; Schmid, Matthias; Pfahlberg, Annette; Uter, Wolfgang; Gefeller, Olaf


    Measurement errors of medico-technical devices can be separated into systematic bias and random error. We propose a new method to address both simultaneously via generalized additive models for location, scale and shape (GAMLSS) in combination with permutation tests. More precisely, we extend a recently proposed boosting algorithm for GAMLSS to provide a test procedure to analyse potential device effects on the measurements. We carried out a large-scale simulation study to provide empirical evidence that our method is able to identify possible sources of systematic bias as well as random error under different conditions. Finally, we apply our approach to compare measurements of skin pigmentation from two different devices in an epidemiological study.

  12. The importance of examining movements within the US health care system: sequential logit modeling

    Directory of Open Access Journals (Sweden)

    Lee Chioun


    Full Text Available Abstract Background Utilization of specialty care may not be a discrete, isolated behavior but rather, a behavior of sequential movements within the health care system. Although patients may often visit their primary care physician and receive a referral before utilizing specialty care, prior studies have underestimated the importance of accounting for these sequential movements. Methods The sample included 6,772 adults aged 18 years and older who participated in the 2001 Survey on Disparities in Quality of Care, sponsored by the Commonwealth Fund. A sequential logit model was used to account for movement in all stages of utilization: use of any health services (i.e., first stage, having a perceived need for specialty care (i.e., second stage, and utilization of specialty care (i.e., third stage. In the sequential logit model, all stages are nested within the previous stage. Results Gender, race/ethnicity, education and poor health had significant explanatory effects with regard to use of any health services and having a perceived need for specialty care, however racial/ethnic, gender, and educational disparities were not present in utilization of specialty care. After controlling for use of any health services and having a perceived need for specialty care, inability to pay for specialty care via income (AOR = 1.334, CI = 1.10 to 1.62 or health insurance (unstable insurance: AOR = 0.26, CI = 0.14 to 0.48; no insurance: AOR = 0.12, CI = 0.07 to 0.20 were significant barriers to utilization of specialty care. Conclusions Use of a sequential logit model to examine utilization of specialty care resulted in a detailed representation of utilization behaviors and patient characteristics that impact these behaviors at all stages within the health care system. After controlling for sequential movements within the health care system, the biggest barrier to utilizing specialty care is the inability to pay, while racial, gender, and educational disparities

  13. Using niche-modelling and species-specific cost analyses to determine a multispecies corridor in a fragmented landscape (United States)

    Zurano, Juan Pablo; Selleski, Nicole; Schneider, Rosio G.


    types independent of the degree of legal protection. These data used with multifocal GIS analyses balance the varying degree of overlap and unique properties among them allowing for comprehensive conservation strategies to be developed relatively rapidly. Our comprehensive approach serves as a model to other regions faced with habitat loss and lack of data. The five carnivores focused on in our study have wide ranges, so the results from this study can be expanded and combined with surrounding countries, with analyses at the species or community level. PMID:28841692

  14. Modeling the potential risk factors of bovine viral diarrhea prevalence in Egypt using univariable and multivariable logistic regression analyses

    Directory of Open Access Journals (Sweden)

    Abdelfattah M. Selim


    Full Text Available Aim: The present cross-sectional study was conducted to determine the seroprevalence and potential risk factors associated with Bovine viral diarrhea virus (BVDV disease in cattle and buffaloes in Egypt, to model the potential risk factors associated with the disease using logistic regression (LR models, and to fit the best predictive model for the current data. Materials and Methods: A total of 740 blood samples were collected within November 2012-March 2013 from animals aged between 6 months and 3 years. The potential risk factors studied were species, age, sex, and herd location. All serum samples were examined with indirect ELIZA test for antibody detection. Data were analyzed with different statistical approaches such as Chi-square test, odds ratios (OR, univariable, and multivariable LR models. Results: Results revealed a non-significant association between being seropositive with BVDV and all risk factors, except for species of animal. Seroprevalence percentages were 40% and 23% for cattle and buffaloes, respectively. OR for all categories were close to one with the highest OR for cattle relative to buffaloes, which was 2.237. Likelihood ratio tests showed a significant drop of the -2LL from univariable LR to multivariable LR models. Conclusion: There was an evidence of high seroprevalence of BVDV among cattle as compared with buffaloes with the possibility of infection in different age groups of animals. In addition, multivariable LR model was proved to provide more information for association and prediction purposes relative to univariable LR models and Chi-square tests if we have more than one predictor.

  15. Spatially quantitative models for vulnerability analyses and resilience measures in flood risk management: Case study Rafina, Greece (United States)

    Karagiorgos, Konstantinos; Chiari, Michael; Hübl, Johannes; Maris, Fotis; Thaler, Thomas; Fuchs, Sven


    We will address spatially quantitative models for vulnerability analyses in flood risk management in the catchment of Rafina, 25 km east of Athens, Greece; and potential measures to reduce damage costs. The evaluation of flood damage losses is relatively advanced. Nevertheless, major problems arise since there are no market prices for the evaluation process available. Moreover, there is particular gap in quantifying the damages and necessary expenditures for the implementation of mitigation measures with respect to flash floods. The key issue is to develop prototypes for assessing flood losses and the impact of mitigation measures on flood resilience by adjusting a vulnerability model and to further develop the method in a Mediterranean region influenced by both, mountain and coastal characteristics of land development. The objective of this study is to create a spatial and temporal analysis of the vulnerability factors based on a method combining spatially explicit loss data, data on the value of exposed elements at risk, and data on flood intensities. In this contribution, a methodology for the development of a flood damage assessment as a function of the process intensity and the degree of loss is presented. It is shown that (1) such relationships for defined object categories are dependent on site-specific and process-specific characteristics, but there is a correlation between process types that have similar characteristics; (2) existing semi-quantitative approaches of vulnerability assessment for elements at risk can be improved based on the proposed quantitative method; and (3) the concept of risk can be enhanced with respect to a standardised and comprehensive implementation by applying the vulnerability functions to be developed within the proposed research. Therefore, loss data were collected from responsible administrative bodies and analysed on an object level. The used model is based on a basin scale approach as well as data on elements at risk exposed

  16. Improvement of a three-dimensional atmospheric dynamic model and examination of its performance over complex terrain

    International Nuclear Information System (INIS)

    Nagai, Haruyasu; Yamazawa, Hiromi


    A three-dimensional atmospheric dynamic model (PHYSIC) was improved and its performance was examined using the meteorological data observed at a coastal area with a complex terrain. To introduce synoptic meteorological conditions into the model, the initial and boundary conditions were improved. By this improvement, the model can predict the temporal change of wind field for more than 24 hours. Moreover, the model successfully simulates the land and sea breeze observed at Shimokita area in the summer of 1992. (author)

  17. Understanding Knowledge Sharing Behavior: An Examination of the Extended Model of Theory of Planned Behavior

    Directory of Open Access Journals (Sweden)

    Sabrina O. Sihombing


    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Knowledge is recognized as one valuable asset for many organizations. Thus, knowledge-sharing is one of important activities in many organizations, including university. Knowledge sharing is defined as activities of transferring or disseminating organizationally relevant information, ideas, suggestions, and expertise with one another. This research applied Christian values as a moderating variable in the framework of theory of planned behavior. The aims of this research to assess applicability of the theory of planned behavior to predict knowledge sharing and to examine the effects of Christian values in the relationship between attitude and intention to share knowledge. A self-administered questionnaire was used to collect the data for this study. The data was then analyzed using structural equation modeling. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  18. Development of fine-resolution analyses and expanded large-scale forcing properties: 2. Scale awareness and application to single-column model experiments (United States)

    Feng, Sha; Li, Zhijin; Liu, Yangang; Lin, Wuyin; Zhang, Minghua; Toto, Tami; Vogelmann, Andrew M.; Endo, Satoshi


    three-dimensional fields have been produced using the Community Gridpoint Statistical Interpolation (GSI) data assimilation system for the U.S. Department of Energy's Atmospheric Radiation Measurement Program (ARM) Southern Great Plains region. The GSI system is implemented in a multiscale data assimilation framework using the Weather Research and Forecasting model at a cloud-resolving resolution of 2 km. From the fine-resolution three-dimensional fields, large-scale forcing is derived explicitly at grid-scale resolution; a subgrid-scale dynamic component is derived separately, representing subgrid-scale horizontal dynamic processes. Analyses show that the subgrid-scale dynamic component is often a major component over the large-scale forcing for grid scales larger than 200 km. The single-column model (SCM) of the Community Atmospheric Model version 5 is used to examine the impact of the grid-scale and subgrid-scale dynamic components on simulated precipitation and cloud fields associated with a mesoscale convective system. It is found that grid-scale size impacts simulated precipitation, resulting in an overestimation for grid scales of about 200 km but an underestimation for smaller grids. The subgrid-scale dynamic component has an appreciable impact on the simulations, suggesting that grid-scale and subgrid-scale dynamic components should be considered in the interpretation of SCM simulations.



    ABASS, Olalere A.; OLAJIDE, Samuel A.; SAMUEL, Babafemi O.


    The traditional method of assessment (examination) is often characterized by examination questions leakages, human errors during marking of scripts and recording of scores. The technological advancement in the field of computer science has necessitated the need for computer usage in majorly all areas of human life and endeavors, education sector not excluded. This work, Web-based Examination System (WES) was, therefore, born out of the will to stymie the problems plaguing the conventional (pa...

  20. Entropic potential field formed for a linear-motor protein near a filament: Statistical-mechanical analyses using simple models (United States)

    Amano, Ken-ichi; Yoshidome, Takashi; Iwaki, Mitsuhiro; Suzuki, Makoto; Kinoshita, Masahiro


    while they form a pointlike one in model 2. We then examine the effects of geometric features of the solute on the amplitudes and asymmetry of the entropic potential field acting on the solute along the filament. A large aspherical solute with a cleft near the solute-filament interface, which mimics the myosin motor domain, is considered in the examination. Thus, the two fields in our physical picture described above are qualitatively reproduced. The factors to be taken into account in further studies are also discussed.

  1. Computational modeling and statistical analyses on individual contact rate and exposure to disease in complex and confined transportation hubs (United States)

    Wang, W. L.; Tsui, K. L.; Lo, S. M.; Liu, S. B.


    Crowded transportation hubs such as metro stations are thought as ideal places for the development and spread of epidemics. However, for the special features of complex spatial layout, confined environment with a large number of highly mobile individuals, it is difficult to quantify human contacts in such environments, wherein disease spreading dynamics were less explored in the previous studies. Due to the heterogeneity and dynamic nature of human interactions, increasing studies proved the importance of contact distance and length of contact in transmission probabilities. In this study, we show how detailed information on contact and exposure patterns can be obtained by statistical analyses on microscopic crowd simulation data. To be specific, a pedestrian simulation model-CityFlow was employed to reproduce individuals' movements in a metro station based on site survey data, values and distributions of individual contact rate and exposure in different simulation cases were obtained and analyzed. It is interesting that Weibull distribution fitted the histogram values of individual-based exposure in each case very well. Moreover, we found both individual contact rate and exposure had linear relationship with the average crowd densities of the environments. The results obtained in this paper can provide reference to epidemic study in complex and confined transportation hubs and refine the existing disease spreading models.

  2. Control volume analyses of glottal flow using a fully-coupled numerical fluid-structure interaction model (United States)

    Yang, Jubiao; Krane, Michael; Zhang, Lucy


    Vocal fold vibrations and the glottal jet are successfully simulated using the modified Immersed Finite Element method (mIFEM), a fully coupled dynamics approach to model fluid-structure interactions. A self-sustained and steady vocal fold vibration is captured given a constant pressure input at the glottal entrance. The flow rates at different axial locations in the glottis are calculated, showing small variations among them due to the vocal fold motion and deformation. To further facilitate the understanding of the phonation process, two control volume analyses, specifically with Bernoulli's equation and Newton's 2nd law, are carried out for the glottal flow based on the simulation results. A generalized Bernoulli's equation is derived to interpret the correlations between the velocity and pressure temporally and spatially along the center line which is a streamline using a half-space model with symmetry boundary condition. A specialized Newton's 2nd law equation is developed and divided into terms to help understand the driving mechanism of the glottal flow.

  3. Bayesian salamanders: analysing the demography of an underground population of the European plethodontid Speleomantes strinatii with state-space modelling

    Directory of Open Access Journals (Sweden)

    Salvidio Sebastiano


    Full Text Available Abstract Background It has been suggested that Plethodontid salamanders are excellent candidates for indicating ecosystem health. However, detailed, long-term data sets of their populations are rare, limiting our understanding of the demographic processes underlying their population fluctuations. Here we present a demographic analysis based on a 1996 - 2008 data set on an underground population of Speleomantes strinatii (Aellen in NW Italy. We utilised a Bayesian state-space approach allowing us to parameterise a stage-structured Lefkovitch model. We used all the available population data from annual temporary removal experiments to provide us with the baseline data on the numbers of juveniles, subadults and adult males and females present at any given time. Results Sampling the posterior chains of the converged state-space model gives us the likelihood distributions of the state-specific demographic rates and the associated uncertainty of these estimates. Analysing the resulting parameterised Lefkovitch matrices shows that the population growth is very close to 1, and that at population equilibrium we expect half of the individuals present to be adults of reproductive age which is what we also observe in the data. Elasticity analysis shows that adult survival is the key determinant for population growth. Conclusion This analysis demonstrates how an understanding of population demography can be gained from structured population data even in a case where following marked individuals over their whole lifespan is not practical.

  4. Time Headway Modelling of Motorcycle-Dominated Traffic to Analyse Traffic Safety Performance and Road Link Capacity of Single Carriageways

    Directory of Open Access Journals (Sweden)

    D. M. Priyantha Wedagama


    Full Text Available This study aims to develop time headway distribution models to analyse traffic safety performance and road link capacities for motorcycle-dominated traffic in Denpasar, Bali. Three road links selected as the case study are Jl. Hayam Wuruk, Jl.Hang Tuah, and Jl. Padma. Data analysis showed that between 55%-80% of motorists in Denpasar during morning and evening peak hours paid less attention to the safe distance with the vehicles in front. The study found that Lognormal distribution models are best to fit time headway data during morning peak hours while either Weibull (3P or Pearson III distributions is for evening peak hours. Road link capacities for mixed traffic predominantly motorcycles are apparently affected by the behaviour of motorists in keeping safe distance with the vehicles in front. Theoretical road link capacities for Jl. Hayam Wuruk, Jl. Hang Tuah and Jl. Padma are 3,186 vehicles/hour, 3,077 vehicles/hour and 1935 vehicles/hour respectively.

  5. Round-robin pretest analyses of a 1:6-scale reinforced concrete containment model subject to static internal pressurization

    International Nuclear Information System (INIS)

    Clauss, D.B.


    Analyses of a 1:6-scale reinforced concrete containment model that will be tested to failure at Sandia National Laboratories in the spring of 1987 were conducted by the following organizations in the United States and Europe: Sandia National Laboratories (USA), Argonne National Laboratory (USA), Electric Power Research Institute (USA), Commissariat a L'Energie Atomique (France), HM Nuclear Installations Inspectorate (UK), Comitato Nazionale per la ricerca e per lo sviluppo dell'Energia Nucleare e delle Energie Alternative (Italy), UK Atomic Energy Authority, Safety and Reliability Directorate (UK), Gesellschaft fuer Reaktorsicherheit (FRG), Brookhaven National Laboratory (USA), and Central Electricity Generating Board (UK). Each organization was supplied with a standard information package, which included construction drawings and actual material properties for most of the materials used in the model. Each organization worked independently using their own analytical methods. This report includes descriptions of the various analytical approaches and pretest predictions submitted by each organization. Significant milestones that occur with increasing pressure, such as damage to the concrete (cracking and crushing) and yielding of the steel components, and the failure pressure (capacity) and failure mechanism are described. Analytical predictions for pressure histories of strain in the liner and rebar and displacements are compared at locations where experimental results will be available after the test. Thus, these predictions can be compared to one another and to experimental results after the test

  6. Best-fit model of exploratory and confirmatory factor analysis of the 2010 Medical Council of Canada Qualifying Examination Part I clinical decision-making cases

    Directory of Open Access Journals (Sweden)

    André F. De Champlain


    Full Text Available Purpose: This study aims to assess the fit of a number of exploratory and confirmatory factor analysis models to the 2010 Medical Council of Canada Qualifying Examination Part I (MCCQE1 clinical decision-making (CDM cases. The outcomes of this study have important implications for a range of domains, including scoring and test development. Methods: The examinees included all first-time Canadian medical graduates and international medical graduates who took the MCCQE1 in spring or fall 2010. The fit of one- to five-factor exploratory models was assessed for the item response matrix of the 2010 CDM cases. Five confirmatory factor analytic models were also examined with the same CDM response matrix. The structural equation modeling software program Mplus was used for all analyses. Results: Out of the five exploratory factor analytic models that were evaluated, a three-factor model provided the best fit. Factor 1 loaded on three medicine cases, two obstetrics and gynecology cases, and two orthopedic surgery cases. Factor 2 corresponded to pediatrics, and the third factor loaded on psychiatry cases. Among the five confirmatory factor analysis models examined in this study, three- and four-factor lifespan period models and the five-factor discipline models provided the best fit. Conclusion: The results suggest that knowledge of broad disciplinary domains best account for performance on CDM cases. In test development, particular effort should be placed on developing CDM cases according to broad discipline and patient age domains; CDM testlets should be assembled largely using the criteria of discipline and age.

  7. The News Model of Asset Price Determination - An Empirical Examination of the Danish Football Club Bröndby IF

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Moritzen; Jörgensen


    According to the news model of asset price determination, only the unexpected component of an information should drive the stock price. We use the Danish publicly listed football club Brøndby IF to analyse how match outcome impacts the stock price. To disentangle gross news from net news, betting...

  8. Examination of Polytomous Items' Psychometric Properties According to Nonparametric Item Response Theory Models in Different Test Conditions (United States)

    Sengul Avsar, Asiye; Tavsancil, Ezel


    This study analysed polytomous items' psychometric properties according to nonparametric item response theory (NIRT) models. Thus, simulated datasets--three different test lengths (10, 20 and 30 items), three sample distributions (normal, right and left skewed) and three samples sizes (100, 250 and 500)--were generated by conducting 20…

  9. Examining the Physical Self in Adolescent Girls Over Time: Further Evidence against the Hierarchical Model. (United States)

    Kowalski, Kent C.; Crocker, Peter R. E.; Kowalski, Nanette P.; Chad, Karen E.; Humbert, M. Louise


    Examined the direction of causal flow between global and specific dimensions of self-concept. Adolescent girls completed the Physical Self-Perception Profile and a global self-esteem scale in 9th and 10th grade. Results showed little support for top-down or bottom-up effects over the year. When self-concept was examined over time, there was…

  10. Respiratory system model for quasistatic pulmonary pressure-volume (P-V) curve: inflation-deflation loop analyses. (United States)

    Amini, R; Narusawa, U


    A respiratory system model (RSM) is developed for the deflation process of a quasistatic pressure-volume (P-V) curve, following the model for the inflation process reported earlier. In the RSM of both the inflation and the deflation limb, a respiratory system consists of a large population of basic alveolar elements, each consisting of a piston-spring-cylinder subsystem. A normal distribution of the basic elements is derived from Boltzmann statistical model with the alveolar closing (opening) pressure as the distribution parameter for the deflation (inflation) process. An error minimization by the method of least squares applied to existing P-V loop data from two different data sources confirms that a simultaneous inflation-deflation analysis is required for an accurate determination of RSM parameters. Commonly used terms such as lower inflection point, upper inflection point, and compliance are examined based on the P-V equations, on the distribution function, as well as on the geometric and physical properties of the basic alveolar element.

  11. FAMULATUR PLUS – A successful model for improving students' physical examination skills?

    Directory of Open Access Journals (Sweden)

    Jerg, Achim


    Full Text Available Introduction/Project description: Several studies have revealed insufficient physical examination skills among medical students, both with regard to the completeness of the physical examination and the accuracy of the techniques used. FAMULATUR PLUS was developed in response to these findings. As part of this practice-oriented instructional intervention, physical examination skills should be taught through examination seminars and problem-oriented learning approaches. In order to ensure practical relevance, all courses are integrated into a 30-day clinical traineeship in the surgery or internal medicine department of a hospital (FAMULATUR PLUS.Research question: Does participation in the FAMULATUR PLUS project lead to a more optimistic self-assessment of examination skills and/or improved performance of the physical examination?Methodology: A total of 49 medical students participated in the study. The inclusion criteria were as follows: enrollment in the clinical studies element of their degree program at the University of Ulm and completion of the university course in internal medicine examinations. Based on their personal preferences, students were assigned to either the intervention (surgery/internal medicine; n=24 or the control group (internal medicine; n=25. All students completed a self-assessment of their physical examination skills in the form of a questionnaire. However, practical examination skills were only assessed in the students in the intervention group. These students were asked to carry out a general physical examination of the simulation patient, which was recorded and evaluated in a standardized manner. In both instances, data collection was carried out prior to and after the intervention. Results: The scores arising from the student self-assessment in the intervention (IG and control groups (CG improves significantly in the pre-post comparison, with average scores increasing from 3.83 (±0.72; IG and 3.54 (±0.37; CG to 1


    Directory of Open Access Journals (Sweden)

    Olalere A. ABASS


    Full Text Available The traditional method of assessment (examination is often characterized by examination questions leakages, human errors during marking of scripts and recording of scores. The technological advancement in the field of computer science has necessitated the need for computer usage in majorly all areas of human life and endeavors, education sector not excluded. This work, Web-based Examination System (WES was, therefore, born out of the will to stymie the problems plaguing the conventional (paper-based examination system by providing a campus-wide service for e-assessment devoid of irregularities and generally fair to examinees and equally enhances instant feedback. This system developed using combination of CSS, HTML, PHP SQL MySQL and Dreamweaver is capable of reducing proportion of workload on examination, grading and reviewing on the part of examiners. Thus, the system enables the release of examination results in record time and without error. WES can serve as an effective solution for mass education evaluation and offers many novel features that cannot be implemented in paper-based systems, such as real time data collection, management and analysis, distributed and interactive assessment towards promoting distance education.

  13. Dynamic examination of the femur in a rat model of osteoporosis after injection of CPC containing ABK and PLLA

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, A.; Kusaka, T.; Sasaki, S.; Takano, I.; Tahara, Y.; Ishii, Y. [Kyorin Univ. School of Medicine, Tokyo (Japan). Dept. of Orthopaedic Surgery


    We developed calcium phosphate cement containing antibiotics and poly lactic acid, and examined the effects on bone strength by injecting the cement into the medullary space of the femur in model rats with osteoporosis. A good strength of bone was obtained over 6 months by injecting bone paste into the medullary space of the femur in model rats with bone formation. (orig.)

  14. Integrating Social Activity Theory and Critical Discourse Analysis: A Multilayered Methodological Model for Examining Knowledge Mediation in Mentoring (United States)

    Becher, Ayelet; Orland-Barak, Lily


    This study suggests an integrative qualitative methodological framework for capturing complexity in mentoring activity. Specifically, the model examines how historical developments of a discipline direct mentors' mediation of professional knowledge through the language that they use. The model integrates social activity theory and a framework of…

  15. Use of Coupled Eutrophication and Network Models for Examination of Fisheries and Eutrophication Processes

    National Research Council Canada - National Science Library

    Cerco, Carl F; Tillman, Dorothy H


    ...) was designed to be a flexible, widely applicable eutrophication model. Ecopath with Ecosim (EWE) is a freely distributed network model supported by the Fisheries Centre, University of British Columbia...

  16. Examining the short term effects of emotion under an Adaptation Level Theory model of tinnitus perception. (United States)

    Durai, Mithila; O'Keeffe, Mary G; Searchfield, Grant D


    Existing evidence suggests a strong relationship between tinnitus and emotion. The objective of this study was to examine the effects of short-term emotional changes along valence and arousal dimensions on tinnitus outcomes. Emotional stimuli were presented in two different modalities: auditory and visual. The authors hypothesized that (1) negative valence (unpleasant) stimuli and/or high arousal stimuli will lead to greater tinnitus loudness and annoyance than positive valence and/or low arousal stimuli, and (2) auditory emotional stimuli, which are in the same modality as the tinnitus, will exhibit a greater effect on tinnitus outcome measures than visual stimuli. Auditory and visual emotive stimuli were administered to 22 participants (12 females and 10 males) with chronic tinnitus, recruited via email invitations send out to the University of Auckland Tinnitus Research Volunteer Database. Emotional stimuli used were taken from the International Affective Digital Sounds- Version 2 (IADS-2) and the International Affective Picture System (IAPS) (Bradley and Lang, 2007a, 2007b). The Emotion Regulation Questionnaire (Gross and John, 2003) was administered alongside subjective ratings of tinnitus loudness and annoyance, and psychoacoustic sensation level matches to external sounds. Males had significantly different emotional regulation scores than females. Negative valence emotional auditory stimuli led to higher tinnitus loudness ratings in males and females and higher annoyance ratings in males only; loudness matches of tinnitus remained unchanged. The visual stimuli did not have an effect on tinnitus ratings. The results are discussed relative to the Adaptation Level Theory Model of Tinnitus. The results indicate that the negative valence dimension of emotion is associated with increased tinnitus magnitude judgements and gender effects may also be present, but only when the emotional stimulus is in the auditory modality. Sounds with emotional associations may be

  17. Effects of wintertime atmospheric river landfalls on surface air temperatures in the Western US: Analyses and model evaluation (United States)

    Kim, J.; Guan, B.; Waliser, D. E.; Ferraro, R.


    Landfalling atmospheric rivers (ARs) affect the wintertime surface air temperatures as shown in earlier studies. The AR-related surface air temperatures can exert significant influence on the hydrology in the US Pacific coast region especially through rainfall-snowfall partitioning and the snowpack in high elevation watersheds as they are directly related with the freezing-level altitudes. These effects of temperature perturbations can in turn affect hydrologic events of various time scales such as flash flooding by the combined effects of rainfall and snowmelt, and the warm season runoff from melting snowpack, especially in conjunction with the AR effects on winter precipitation and rain-on-snow events in WUS. Thus, understanding the effects of AR landfalls on the surface temperatures and examining the capability of climate models in simulating these effects are an important practical concern for WUS. This study aims to understand the effects of AR landfalls on the characteristics of surface air temperatures in WUS, especially seasonal means and PDFs and to evaluate the fidelity of model data produced in the NASA downscaling experiment for the 10 winters from Nov. 1999 to Mar. 2010 using an AR-landfall chronology based on the vertically-integrated water vapor flux calculated from the MERRA2 reanalysis. Model skill is measured using metrics including regional means, a skill score based on correlations and mean-square errors, the similarity between two PDF shapes, and Taylor diagrams. Results show that the AR landfalls are related with higher surface air temperatures in WUS, especially in inland regions. The AR landfalls also reduce the range of surface air temperature PDF, largely by reducing the events in the lower temperature range. The shift in the surface air temperature PDF is consistent with the positive anomalies in the winter-mean temperature. Model data from the NASA downscaling experiment reproduce the AR effects on the temperature PDF, at least

  18. Multi-state Markov models for disease progression in the presence of informative examination times: an application to hepatitis C. (United States)

    Sweeting, M J; Farewell, V T; De Angelis, D


    In many chronic diseases it is important to understand the rate at which patients progress from infection through a series of defined disease states to a clinical outcome, e.g. cirrhosis in hepatitis C virus (HCV)-infected individuals or AIDS in HIV-infected individuals. Typically data are obtained from longitudinal studies, which often are observational in nature, and where disease state is observed only at selected examinations throughout follow-up. Transition times between disease states are therefore interval censored. Multi-state Markov models are commonly used to analyze such data, but rely on the assumption that the examination times are non-informative, and hence the examination process is ignorable in a likelihood-based analysis. In this paper we develop a Markov model that relaxes this assumption through the premise that the examination process is ignorable only after conditioning on a more regularly observed auxiliary variable. This situation arises in a study of HCV disease progression, where liver biopsies (the examinations) are sparse, irregular, and potentially informative with respect to the transition times. We use additional information on liver function tests (LFTs), commonly collected throughout follow-up, to inform current disease state and to assume an ignorable examination process. The model developed has a similar structure to a hidden Markov model and accommodates both the series of LFT measurements and the partially latent series of disease states. We show through simulation how this model compares with the commonly used ignorable Markov model, and a Markov model that assumes the examination process is non-ignorable. Copyright 2010 John Wiley & Sons, Ltd.

  19. Examining the impacts of increased corn production on groundwater quality using a coupled modeling system (United States)

    U.S. Environmental Protection Agency — This dataset was used to create graphics associated with manuscript: Garcia et al., Examining the impacts of increased corn production on groundwater quality using a...

  20. Expression Analyses of ABCDE Model Genes and Changes in Levels of Endogenous Hormones in Chinese Cabbage Exhibiting Petal-Loss

    Directory of Open Access Journals (Sweden)

    Chuan MENG


    Full Text Available Abnormal formation of floral organs affects plant reproduction and can directly interfere with the progress of breeding programs. Using PCR amplification, ABCDE model genes BraAP2, BraAP3, BraPI, BraAG, BraSHP, and BraSEP were isolated from Chinese cabbage (Brassica rapa L. ssp. pekinensis. We examined six development stages of floral buds collected from Chinese cabbage and compared between a line demonstrating normal flowering (A-8 and two mutated lines that exhibited plants having petal-loss (A-16 and A-17. The expression of ABCDE model genes has been analyzed by qRT-PCR. Compared with flower buds of petal-loss plants and normal plants, the expression of A-class gene BraAP2 was significantly decreased during the first to fourth stages, C-class gene BraAG expression was significantly decreased during the first to fifth stages, and D-class gene BraSHP expression was significantly decreased during the first to third stages. Furthermore, B-class gene BraAP3 and BraPI and E-class gene BraSEP expressions were significantly decreased during all six stages of petal-loss plants compared with normal plants. Enzyme-linked immunosorbent assays detected nine endogenous phytohormones during all stages examined here. Except for the second-stage and third-stage buds, levels of the auxin IAA and cytokinin dhZR were always higher in the petal-loss plants than the normal plants at corresponding time points. Meanwhile, concentrations of GA1+3 at the first, fourth, and fifth stages were higher in the petal-loss plants than in the normal plants. Our results provide a theoretical basis for future exploration of the molecular mechanism that determines petal loss and the effects that hormones have on such development in Chinese cabbage plants.

  1. Examining the Effects of Video Modeling and Prompts to Teach Activities of Daily Living Skills. (United States)

    Aldi, Catarina; Crigler, Alexandra; Kates-McElrath, Kelly; Long, Brian; Smith, Hillary; Rehak, Kim; Wilkinson, Lisa


    Video modeling has been shown to be effective in teaching a number of skills to learners diagnosed with autism spectrum disorders (ASD). In this study, we taught two young men diagnosed with ASD three different activities of daily living skills (ADLS) using point-of-view video modeling. Results indicated that both participants met criterion for all ADLS. Participants did not maintain mastery criterion at a 1-month follow-up, but did score above baseline at maintenance with and without video modeling. • Point-of-view video models may be an effective intervention to teach daily living skills. • Video modeling with handheld portable devices (Apple iPod or iPad) can be just as effective as video modeling with stationary viewing devices (television or computer). • The use of handheld portable devices (Apple iPod and iPad) makes video modeling accessible and possible in a wide variety of environments.

  2. Water flow experiments and analyses on the cross-flow type mercury target model with the flow guide plates

    CERN Document Server

    Haga, K; Kaminaga, M; Hino, R


    A mercury target is used in the spallation neutron source driven by a high-intensity proton accelerator. In this study, the effectiveness of the cross-flow type mercury target structure was evaluated experimentally and analytically. Prior to the experiment, the mercury flow field and the temperature distribution in the target container were analyzed assuming a proton beam energy and power of 1.5 GeV and 5 MW, respectively, and the feasibility of the cross-flow type target was evaluated. Then the average water flow velocity field in the target mock-up model, which was fabricated from Plexiglass for a water experiment, was measured at room temperature using the PIV technique. Water flow analyses were conducted and the analytical results were compared with the experimental results. The experimental results showed that the cross-flow could be realized in most of the proton beam path area and the analytical result of the water flow velocity field showed good correspondence to the experimental results in the case w...

  3. The reasoned/reactive model: A new approach to examining eating decisions among female college dieters and nondieters. (United States)

    Ruhl, Holly; Holub, Shayla C; Dolan, Elaine A


    Female college students are prone to unhealthy eating patterns that can impact long-term health. This study examined female students' healthy and unhealthy eating behaviors with three decision-making models. Specifically, the theory of reasoned action, prototype/willingness model, and new reasoned/reactive model were compared to determine how reasoned (logical) and reactive (impulsive) factors relate to dietary decisions. Females (N=583, M age =20.89years) completed measures on reasoned cognitions about foods (attitudes, subjective norms, nutrition knowledge, intentions to eat foods), reactive cognitions about foods (prototypes, affect, willingness to eat foods), dieting, and food consumption. Structural equation modeling (SEM) revealed the new reasoned/reactive model to be the preeminent model for examining eating behaviors. This model showed that attitudes were related to intentions and willingness to eat healthy and unhealthy foods. Affect was related to willingness to eat healthy and unhealthy foods, whereas nutrition knowledge was related to intentions and willingness to eat healthy foods only. Intentions and willingness were related to healthy and unhealthy food consumption. Dieting status played a moderating role in the model and revealed mean-level differences between dieters and nondieters. This study highlights the importance of specific factors in relation to female students' eating decisions and unveils a comprehensive model for examining health behaviors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Examination of evaporative fraction diurnal behaviour using a soil-vegetation model coupled with a mixed-layer model

    Directory of Open Access Journals (Sweden)

    J.-P. Lhomme


    Full Text Available In many experimental conditions, the evaporative fraction, defined as the ratio between evaporation and available energy, has been found stable during daylight hours. This constancy is investigated over fully covering vegetation by means of a land surface scheme coupled with a mixed-layer model, which accounts for entrainment of overlying air. The evaporation rate follows the Penman-Monteith equation and the surface resistance is given by a Jarvis type parameterization involving solar radiation, saturation deficit and leaf water potential. The diurnal course of the evaporative fraction is examined, together with the influence of environmental factors (soil water availability, solar radiation input, wind velocity, saturation deficit above the well-mixed layer. In conditions of fair weather, the curves representing the diurnal course of the evaporative fraction have a typical concave-up shape. Around midday (solar time these curves appear as relatively constant, but always lower that the daytime mean value. Evaporative fraction decreases when soil water decreases or when solar energy increases. An increment of saturation deficit above the mixed-layer provokes only a slight increase of evaporative fraction, and wind velocity has almost no effect. The possibility of estimation daytime evaporation from daytime available energy multiplied by the evaporative fraction at a single time of the day is also investigated. It appears that it is possible to obtain fairly good estimates of daytime evaporation by choosing adequately the time of the measurement of the evaporative fraction. The central hours of the day, and preferably about 3 hr before or after noon, are the most appropriate to provide good estimates. The estimation appears also to be much better when soil water availability (or evaporation is high than when it is low.

  5. Examining secular trend  and seasonality in count data using dynamic generalized linear modelling

    DEFF Research Database (Denmark)

    Lundbye-Christensen, Søren; Dethlefsen, Claus; Gorst-Rasmussen, Anders

    Aims  Time series of incidence counts often show secular trends and seasonal patterns. We present a model for incidence counts capable of handling a possible gradual change in growth rates and seasonal patterns, serial correlation and overdispersion. Methods  The model resembles an ordinary time...... series regression model for Poisson counts. It differs in allowing the regression coefficients to vary gradually over time in a random fashion. Data  In the period January 1980 to 1999, 17,989 incidents of acute myocardial infarction were recorded in the county of Northern Jutland, Denmark. Records were...... updated daily. Results  The model with a seasonal pattern and an approximately linear trend was fitted to the data, and diagnostic plots indicate a good model fit. The analysis with the dynamic model revealed peaks coinciding with influenza epidemics. On average the peak-to-trough ratio is estimated...

  6. Modeling Acequia Irrigation Systems Using System Dynamics: Model Development, Evaluation, and Sensitivity Analyses to Investigate Effects of Socio-Economic and Biophysical Feedbacks

    Directory of Open Access Journals (Sweden)

    Benjamin L. Turner


    Full Text Available Agriculture-based irrigation communities of northern New Mexico have survived for centuries despite the arid environment in which they reside. These irrigation communities are threatened by regional population growth, urbanization, a changing demographic profile, economic development, climate change, and other factors. Within this context, we investigated the extent to which community resource management practices centering on shared resources (e.g., water for agricultural in the floodplains and grazing resources in the uplands and mutualism (i.e., shared responsibility of local residents to maintaining traditional irrigation policies and upholding cultural and spiritual observances embedded within the community structure influence acequia function. We used a system dynamics modeling approach as an interdisciplinary platform to integrate these systems, specifically the relationship between community structure and resource management. In this paper we describe the background and context of acequia communities in northern New Mexico and the challenges they face. We formulate a Dynamic Hypothesis capturing the endogenous feedbacks driving acequia community vitality. Development of the model centered on major stock-and-flow components, including linkages for hydrology, ecology, community, and economics. Calibration metrics were used for model evaluation, including statistical correlation of observed and predicted values and Theil inequality statistics. Results indicated that the model reproduced trends exhibited by the observed system. Sensitivity analyses of socio-cultural processes identified absentee decisions, cumulative income effect on time in agriculture, and land use preference due to time allocation, community demographic effect, effect of employment on participation, and farm size effect as key determinants of system behavior and response. Sensitivity analyses of biophysical parameters revealed that several key parameters (e.g., acres per

  7. A Qualitative Examination of the Importance of Female Role Models in Investment Banks


    Sealy, Ruth


    A number of practitioner surveys across a range of industries have cited the lack of senior female role models as a barrier to career progression. There is very little academic literature to explain this at a senior organizational level. An initial review of the extant role model literature led to the inclusion of two further related areas – organizational demographics, as a contextual factor affecting the availability of role models, and work identity development as a link bet...

  8. Updated model for radionuclide transport in the near-surface till at Forsmark - Implementation of decay chains and sensitivity analyses

    Energy Technology Data Exchange (ETDEWEB)

    Pique, Angels; Pekala, Marek; Molinero, Jorge; Duro, Lara; Trinchero, Paolo; Vries, Luis Manuel de [Amphos 21 Consulting S.L., Barcelona (Spain)


    tendency to overestimate radionuclide concentrations at the discharge zone). Specifically, examination of the modelling results indicates that: 1. The implementation of the revised till stratigraphy has an overall small impact on the modelling results: despite distinctly different groundwater flow patterns, tracer arrival at the discharge zone is similar between the previous and current till models. 2. Of the radionuclides studied only {sup 226}Ra is significantly affected by radioactive chain decay dynamics. 3. The values of geochemical parameters used in the Base Case reactive transport calculations produce conservative results. 4. The model is largely insensitive to significant variations in dispersivity of the till and an alternative definition of the shallow groundwater inflow, although the elimination of vertical stratification in hydraulic conductivity has the effect to speed up radionuclide transport. 5. Over saturation with barite is not reached under any of the considered scenarios hence Ra coprecipitation with barite does not contribute to {sup 226}Ra retardation under the assumptions of the model. In contrast, Sr co-precipitation with calcite is an important retention mechanism for {sup 90}Sr.

  9. Epidemiology of HPV 16 and cervical cancer in Finland and the potential impact of vaccination: mathematical modelling analyses.

    Directory of Open Access Journals (Sweden)

    Ruanne V Barnabas


    Full Text Available BACKGROUND: Candidate human papillomavirus (HPV vaccines have demonstrated almost 90%-100% efficacy in preventing persistent, type-specific HPV infection over 18 mo in clinical trials. If these vaccines go on to demonstrate prevention of precancerous lesions in phase III clinical trials, they will be licensed for public use in the near future. How these vaccines will be used in countries with national cervical cancer screening programmes is an important question. METHODS AND FINDINGS: We developed a transmission model of HPV 16 infection and progression to cervical cancer and calibrated it to Finnish HPV 16 seroprevalence over time. The model was used to estimate the transmission probability of the virus, to look at the effect of changes in patterns of sexual behaviour and smoking on age-specific trends in cancer incidence, and to explore the impact of HPV 16 vaccination. We estimated a high per-partnership transmission probability of HPV 16, of 0.6. The modelling analyses showed that changes in sexual behaviour and smoking accounted, in part, for the increase seen in cervical cancer incidence in 35- to 39-y-old women from 1990 to 1999. At both low (10% in opportunistic immunisation and high (90% in a national immunisation programme coverage of the adolescent population, vaccinating women and men had little benefit over vaccinating women alone. We estimate that vaccinating 90% of young women before sexual debut has the potential to decrease HPV type-specific (e.g., type 16 cervical cancer incidence by 91%. If older women are more likely to have persistent infections and progress to cancer, then vaccination with a duration of protection of less than 15 y could result in an older susceptible cohort and no decrease in cancer incidence. While vaccination has the potential to significantly reduce type-specific cancer incidence, its combination with screening further improves cancer prevention. CONCLUSIONS: HPV vaccination has the potential to

  10. Examining the Etiology of Reading Disability as Conceptualized by the Hybrid Model (United States)

    Erbeli, Florina; Hart, Sara A.; Wagner, Richard K.; Taylor, Jeanette


    A fairly recent definition of reading disability (RD) is that in the form of a hybrid model. The model views RD as a latent construct that is manifested through various observable unexpected impairments in reading-related skills and through inadequate response to intervention. The current report evaluated this new conceptualization of RD from an…

  11. Developing a Model for an Innovative Culinary Competency Curriculum and Examining Its Effects on Students' Performance (United States)

    Hu, Meng-Lei I-Chen Monica; Horng, Jeou-Shyan; Teng, Chih-Ching


    The present study designs and develops an innovative culinary competency curriculum (ICCC) model comprising seven sections: innovative culture, aesthetics, techniques, service, product, management, and creativity. The model is formulated based on culinary concept, creativity, innovation, and competency theory. The four elements of curriculum…

  12. Prediction Models for Licensure Examination Performance using Data Mining Classifiers for Online Test and Decision Support System

    Directory of Open Access Journals (Sweden)

    Ivy M. Tarun


    Full Text Available This study focuse d on two main points: the generation of licensure examination performan ce prediction models; and the development of a Decision Support System. In this study, data mining classifiers were used to generate the models using WEKA (Waikato Environment for Knowledge Analysis. These models were integrated into the Decision Support System as default models to support decision making as far as appropriate interventions during review sessions are concerned. The system developed mainly involves the repeated generation of MR models for performance prediction and also provides a Mock Boar d Exam for the reviewees to take. From the models generated, it is established that the General Weighted Average of the reviewees in their General Education subjects, the result of the Mock Board Exam and the instance when the reviewee is conducting a sel f - review are good predictors of the licensure examination performance. Further , it is concluded that the General Weighted Average of the reviewees in their Major or Content courses is the best predictor of licensure examination performance. Based from the evaluation results of the system , the system satisfied its implied functions and is efficient, usable, reliable and portable. Hence, it can already be used not as a substitute to the face - to - face review sessions but to enhance the reviewees’ licensure exa mination review and allow initial identification of those who are likely to have difficulty in passing the licensure examination, therefore providing sufficient time and opportunities for appropriate interventions.

  13. Intercomparison and analyses of the climatology of the West African monsoon in the West African monsoon modeling and evaluation project (WAMME) first model intercomparison experiment

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Yongkang; Sales, Fernando De [University of California, Los Angeles, CA (United States); Lau, W.K.M.; Schubert, Siegfried D.; Wu, Man-Li C. [NASA, Goddard Space Flight Center, Greenbelt, MD (United States); Boone, Aaron [Centre National de Recherches Meteorologiques, Meteo-France Toulouse, Toulouse (France); Feng, Jinming [University of California, Los Angeles, CA (United States); Chinese Academy of Sciences, Institute of Atmospheric Physics, Beijing (China); Dirmeyer, Paul; Guo, Zhichang [Center for Ocean-Land-Atmosphere Interactions, Calverton, MD (United States); Kim, Kyu-Myong [University of Maryland Baltimore County, Baltimore, MD (United States); Kitoh, Akio [Meteorological Research Institute, Tsukuba (Japan); Kumar, Vadlamani [National Center for Environmental Prediction, Camp Springs, MD (United States); Wyle Information Systems, Gaithersburg, MD (United States); Poccard-Leclercq, Isabelle [Universite de Bourgogne, Centre de Recherches de Climatologie UMR5210 CNRS, Dijon (France); Mahowald, Natalie [Cornell University, Ithaca, NY (United States); Moufouma-Okia, Wilfran; Rowell, David P. [Met Office Hadley Centre, Exeter (United Kingdom); Pegion, Phillip [NASA, Goddard Space Flight Center, Greenbelt, MD (United States); National Center for Environmental Prediction, Camp Springs, MD (United States); Schemm, Jae; Thiaw, Wassila M. [National Center for Environmental Prediction, Camp Springs, MD (United States); Sealy, Andrea [The Caribbean Institute for Meteorology and Hydrology, St. James (Barbados); Vintzileos, Augustin [National Center for Environmental Prediction, Camp Springs, MD (United States); Science Applications International Corporation, Camp Springs, MD (United States); Williams, Steven F. [National Center for Atmospheric Research, Boulder, CO (United States)


    This paper briefly presents the West African monsoon (WAM) modeling and evaluation project (WAMME) and evaluates WAMME general circulation models' (GCM) performances in simulating variability of WAM precipitation, surface temperature, and major circulation features at seasonal and intraseasonal scales in the first WAMME experiment. The analyses indicate that models with specified sea surface temperature generally have reasonable simulations of the pattern of spatial distribution of WAM seasonal mean precipitation and surface temperature as well as the averaged zonal wind in latitude-height cross-section and low level circulation. But there are large differences among models in simulating spatial correlation, intensity, and variance of precipitation compared with observations. Furthermore, the majority of models fail to produce proper intensities of the African Easterly Jet (AEJ) and the tropical easterly jet. AMMA Land Surface Model Intercomparison Project (ALMIP) data are used to analyze the association between simulated surface processes and the WAM and to investigate the WAM mechanism. It has been identified that the spatial distributions of surface sensible heat flux, surface temperature, and moisture convergence are closely associated with the simulated spatial distribution of precipitation; while surface latent heat flux is closely associated with the AEJ and contributes to divergence in AEJ simulation. Common empirical orthogonal functions (CEOF) analysis is applied to characterize the WAM precipitation evolution and has identified a major WAM precipitation mode and two temperature modes (Sahara mode and Sahel mode). Results indicate that the WAMME models produce reasonable temporal evolutions of major CEOF modes but have deficiencies/uncertainties in producing variances explained by major modes. Furthermore, the CEOF analysis shows that WAM precipitation evolution is closely related to the enhanced Sahara mode and the weakened Sahel mode, supporting

  14. The Marginalized "Model" Minority: An Empirical Examination of the Racial Triangulation of Asian Americans (United States)

    Xu, Jun; Lee, Jennifer C.


    In this article, we propose a shift in race research from a one-dimensional hierarchical approach to a multidimensional system of racial stratification. Building upon Claire Kim's (1999) racial triangulation theory, we examine how the American public rates Asians relative to blacks and whites along two dimensions of racial stratification: racial…

  15. An Effective School Autonomy Model: Examining Headteachers' Job Satisfaction and Work-Related Stress (United States)

    Nicolaidou Solomou, Galatia; Pashiardis, Petros


    Purpose: Although school autonomy has been a matter of great interest during the last decades and several relevant measures have been implemented toward this end, the relation between school autonomy and school effectiveness has not been examined thoroughly. The purpose of this paper is to explore this relation and to propose an effective school…

  16. Examining Technology Perception of Social Studies Teachers with Rogers' Diffusion Model (United States)

    Akman, Özkan; Koçoglu, Erol


    Mobile learning has started to take place in education literature with the developing technology, and this technology started to have an increasing spread along with its advantages. This study examines the responses of social studies teachers to the innovations in the field of mobile learning. The study was designed within the framework of theory…

  17. Examination of a Process Model of Adolescent Smoking Self-Change Efforts in Relation to Gender (United States)

    MacPherson, Laura; Myers, Mark G.


    Little information describes how adolescents change their smoking behavior. This study investigated the role of gender in the relationship of motivation and cognitive variables with adolescent smoking self-change efforts. Self-report and semi-structured interview data from a prospective study of smoking self-change efforts were examined among 98…

  18. Examining Pictorial Models and Virtual Manipulatives for Third-Grade Fraction Instruction (United States)

    Moyer-Packenham, Patricia S.; Ulmer, Lori A.; Anderson, Katie L.


    The purpose of this study was to examine pictorial representations, whether in static or dynamic modalities, and their impact on student learning in a classroom with low-achieving students. The investigation emerged from a classroom teacher's action research project. During a three-week fraction unit, nineteen third-grade low-achieving students…

  19. Examining the Structure of Vocational Interests in Turkey in the Context of the Personal Globe Model (United States)

    Vardarli, Bade; Özyürek, Ragip; Wilkins-Yel, Kerrie G.; Tracey, Terence J. G.


    The structural validity of the Personal Globe Inventory-Short (PGI-S: Tracey in J Vocat Behavi 76:1-15, 2010) was examined in a Turkish sample of high school and university students. The PGI-S measures eight basic interest scales, Holland's ("Making vocational choice," Prentice-Hall, Englewood Cliffs, 1997) six types, Prediger's ("J…

  20. Examining Big-Fish-Little-Pond-Effects across 49 Countries: A Multilevel Latent Variable Modelling Approach (United States)

    Wang, Ze


    Using data from the Trends in International Mathematics and Science Study (TIMSS) 2007, this study examined the big-fish-little-pond-effects (BFLPEs) in 49 countries. In this study, the effect of math ability on math self-concept was decomposed into a within- and a between-level components using implicit mean centring and the complex data…

  1. Examination of Soil Moisture Retrieval Using SIR-C Radar Data and a Distributed Hydrological Model (United States)

    Hsu, A. Y.; ONeill, P. E.; Wood, E. F.; Zion, M.


    A major objective of soil moisture-related hydrological-research during NASA's SIR-C/X-SAR mission was to determine and compare soil moisture patterns within humid watersheds using SAR data, ground-based measurements, and hydrologic modeling. Currently available soil moisture-inversion methods using active microwave data are only accurate when applied to bare and slightly vegetated surfaces. Moreover, as the surface dries down, the number of pixels that can provide estimated soil moisture by these radar inversion methods decreases, leading to less accuracy and, confidence in the retrieved soil moisture fields at the watershed scale. The impact of these errors in microwave- derived soil moisture on hydrological modeling of vegetated watersheds has yet to be addressed. In this study a coupled water and energy balance model operating within a topographic framework is used to predict surface soil moisture for both bare and vegetated areas. In the first model run, the hydrological model is initialized using a standard baseflow approach, while in the second model run, soil moisture values derived from SIR-C radar data are used for initialization. The results, which compare favorably with ground measurements, demonstrate the utility of combining radar-derived surface soil moisture information with basin-scale hydrological modeling.

  2. Preclinical QSP Modeling in the Pharmaceutical Industry: An IQ Consortium Survey Examining the Current Landscape. (United States)

    Nijsen, Marjoleen J M A; Wu, Fan; Bansal, Loveleena; Bradshaw-Pierce, Erica; Chan, Jason R; Liederer, Bianca M; Mettetal, Jerome T; Schroeder, Patricia; Schuck, Edgar; Tsai, Alice; Xu, Christine; Chimalakonda, Anjaneya; Le, Kha; Penney, Mark; Topp, Brian; Yamada, Akihiro; Spilker, Mary E


    A cross-industry survey was conducted to assess the landscape of preclinical quantitative systems pharmacology (QSP) modeling within pharmaceutical companies. This article presents the survey results, which provide insights on the current state of preclinical QSP modeling in addition to future opportunities. Our results call attention to the need for an aligned definition and consistent terminology around QSP, yet highlight the broad applicability and benefits preclinical QSP modeling is currently delivering. © 2018 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

  3. Effect of health-belief-model-based training on performance of women in breast self-examination. (United States)

    Nahidi, Fatemeh; Dolatian, Mahrokh; Roozbeh, Nasibeh; Asadi, Zeynab; Shakeri, Nezhat


    Breast cancer is the most common cause of cancer death among women in the world. With prevention and examinations, including breast self-examination, the death rate will be reduced. The purpose of this study was to determine the effect of health-belief-model-based training on the performance of women in breast self-examination in the province of Fars (Iran). An empirical study examined the effect of an eight-week training program based on the health belief model among 144 women who visited health care centers in the city of Abadeh in Fars Province (Iran) in 2015. Data gathered through researcher-made questionnaires including awareness, components of the health belief model, performance, and demographic information. IBM-SPSS software version 20, descriptive and inferential statistical tests such as T-test, chi-square, Mann-Whitney, and repeated measurements were used for data analysis. After the intervention, a significant difference was seen in average awareness, perceived susceptibility, and performance of women (phealth belief model with an increase of the perceived susceptibility could be effective in improving their performance in breast self-examination.

  4. Examining the impacts of increased corn production on groundwater quality using a coupled modeling system (United States)

    This study demonstrates the value of a coupled chemical transport modeling system for investigating groundwater nitrate contamination responses associated with nitrogen (N) fertilizer application and increased corn production. The coupled Community Multiscale Air Quality Bidirect...

  5. Formulation, Implementation and Examination of Vertical Coordinate Choices in the Global Navy Coastal Ocean Model (NCOM)

    National Research Council Canada - National Science Library

    Barron, Charlie N; Kara, A. B; Martin, Paul J; Rhodes, Robert C; Smedstad, Lucy F


    .... NCOM is a baroclinic, hydrostatic, Boussinesq, free-surface ocean model that allows its vertical coordinate to consist of sigma coordinates for the upper layers and z-levels below a user-specified depth...

  6. Examining Competing Models of Transformational Leadership, Leadership Trust, Change Commitment, and Job Satisfaction. (United States)

    Yang, Yi-Feng


    This study discusses the influence of transformational leadership on job satisfaction through assessing six alternative models related to the mediators of leadership trust and change commitment utilizing a data sample (N = 341; M age = 32.5 year, SD = 5.2) for service promotion personnel in Taiwan. The bootstrap sampling technique was used to select the better fitting model. The tool of hierarchical nested model analysis was applied, along with the approaches of bootstrapping mediation, PRODCLIN2, and structural equation modeling comparison. The results overall demonstrate that leadership is important and that leadership role identification (trust) and workgroup cohesiveness (commitment) form an ordered serial relationship. © The Author(s) 2016.

  7. A second-generation device for automated training and quantitative behavior analyses of molecularly-tractable model organisms.

    Directory of Open Access Journals (Sweden)

    Douglas Blackiston


    Full Text Available A deep understanding of cognitive processes requires functional, quantitative analyses of the steps leading from genetics and the development of nervous system structure to behavior. Molecularly-tractable model systems such as Xenopus laevis and planaria offer an unprecedented opportunity to dissect the mechanisms determining the complex structure of the brain and CNS. A standardized platform that facilitated quantitative analysis of behavior would make a significant impact on evolutionary ethology, neuropharmacology, and cognitive science. While some animal tracking systems exist, the available systems do not allow automated training (feedback to individual subjects in real time, which is necessary for operant conditioning assays. The lack of standardization in the field, and the numerous technical challenges that face the development of a versatile system with the necessary capabilities, comprise a significant barrier keeping molecular developmental biology labs from integrating behavior analysis endpoints into their pharmacological and genetic perturbations. Here we report the development of a second-generation system that is a highly flexible, powerful machine vision and environmental control platform. In order to enable multidisciplinary studies aimed at understanding the roles of genes in brain function and behavior, and aid other laboratories that do not have the facilities to undergo complex engineering development, we describe the device and the problems that it overcomes. We also present sample data using frog tadpoles and flatworms to illustrate its use. Having solved significant engineering challenges in its construction, the resulting design is a relatively inexpensive instrument of wide relevance for several fields, and will accelerate interdisciplinary discovery in pharmacology, neurobiology, regenerative medicine, and cognitive science.

  8. A New Model to Facilitate Individualized Case Conceptualization and Treatment of Social Phobia: An Examination and Reaction to Moscovitch's Model (United States)

    Heimberg, Richard G.


    Moscovitch's (2009) model of social phobia is put forth as an integration and extension of previous cognitive-behavioral models. The author asserts that his approach overcomes a number of shortcomings of previous models and will serve to better guide case conceptualization, treatment planning, and intervention implementation for clients with…

  9. Examining Policies to Reduce Homelessness Using a General Equilibrium Model of the Housing Market


    Mansur, Erin; Quigley, John M.; Raphael, Steven; Smolensky, Eugene


    In this paper, we use a general equilibrium simulation model to assess the potential impacts on homelessness of various housing-market policy interventions. We calibrate the model to the four largest metropolitan areas in California. We explore the welfare con- sequences and the effects on homelessness of three housing-market policy interventions: extending housing vouchers to all low-income households, subsidizing all landlords, and subsidizing those landlords who supply low-income housing. ...

  10. One of Us: Multilevel Models Examining the Impact of Descriptive Representation on Civic Engagement


    Norris, Pippa; Krook, Mona Lena


    This paper examines the impact of descriptive representation in comparative perspective. The goals are to establish (1) whether descriptive representation mobilizes attitudinal and behavioral indicators of civic engagement; (2) whether the strength of any such relationship differs for women and young people; and (3) whether this relationship is evident cross-nationally. The first section provides an overview of existing research on descriptive representation and the civic engagement of women ...

  11. An examination of adaptive cellular protective mechanisms using a multi-stage carcinogenesis model

    International Nuclear Information System (INIS)

    Schollnberger, H.; Stewart, R. D.; Mitchel, R. E. J.; Hofmann, W.


    A multi-stage cancer model that describes the putative rate-limiting steps in carcinogenesis was developed and used to investigate the potential impact on lung cancer incidence of the hormesis mechanisms suggested by Feinendegen and Pollycove. In this deterministic cancer model, radiation and endogenous processes damage the DNA of target cells in the lung. Some fraction of the misrepaired our unrepaired DNA damage induces genomic instability and, ultimately, leads to the accumulation of malignant cells. The model accounts for cell birth and death processes. Ita also includes a rate of malignant transformation and a lag period for tumour formation. Cellular defence mechanisms are incorporated into the model by postulating dose and dose rate dependent radical scavenging. The accuracy of DNA damage repair also depends on dose and dose rate. Sensitivity studies were conducted to identify critical model inputs and to help define the shapes of the cumulative lung cancer incidence curves that may arise when dose and dose rate dependent cellular defence mechanisms are incorporated into a multi-stage cancer model. For lung cancer, both linear no-threshold (LNT) and non-LNT shaped responses can be obtained. The reported studied clearly show that it is critical to know whether or not and to what extent multiply damaged DNA sites are formed by endogenous processes. Model inputs that give rise to U-shaped responses are consistent with an effective cumulative lung cancer incidence threshold that may be as high as 300 mGy (4 mGy per year for 75 years). (Author) 11 refs

  12. Examining the Effects of Model-Based Inquiry on Concepetual Understanding and Engagement in Science (United States)

    Baze, Christina L.

    Model-Based Inquiry (MBI) is an instructional model which engages students in the scientific practices of modeling, explanation, and argumentation while they work to construct explanations for natural phenomena. This instructional model has not been previously studied at the community college level. The purpose of this study is to better understand how MBI affects the development of community college students' conceptual understanding of evolution and engagement in the practices of science. Mixed-methods were employed to collect quantitative and qualitative data through the multiple-choice Concepts Inventory of Natural Selection, student artifacts, and semi-structured interviews. Participants were enrolled in Biology Concepts, an introductory class for non-science majors, at a small, rural community college in the southwestern United States. Preliminary data shows that conceptual understanding is not adversely affected by the implementation of MBI, and that students gain valuable insights into the practices of science. Specifically, students who participated in the MBI intervention group gained a better understanding of the role of models in explaining and predicting phenomena and experienced feeling ownership of their ideas, an appropriate depth of thinking, more opportunities for collaboration, and coherence and context within the unit. Implications of this study will be of interest to postsecondary science educators and researchers who seek to reform and improve science education.

  13. Examining wide-arc digital breast tomosynthesis: optimization using a visual-search model observer (United States)

    Das, Mini; Liang, Zhihua; Gifford, Howard C.


    Mathematical model observers are expected to assist in preclinical optimization of image acquisition and reconstruction parameters. A clinically realistic and robust model observer platform could help in multiparameter optimizations without requiring frequent human-observer validations. We are developing search-capable visual-search (VS) model observers with this potential. In this work, we present initial results on optimization of DBT scan angle and the number of projection views for low-contrast mass detection. Comparison with human-observer results shows very good agreement. These results point towards the benefits of using relatively wider arcs and low projection angles per arc degree for improved mass detection. These results are particularly interesting considering that the FDA-approved DBT systems like Hologic Selenia Dimensions uses a narrow (15-degree) acquisition arc and one projection per arc degree.

  14. Century-scale variability in global annual runoff examined using a water balance model (United States)

    McCabe, G.J.; Wolock, D.M.


    A monthly water balance model (WB model) is used with CRUTS2.1 monthly temperature and precipitation data to generate time series of monthly runoff for all land areas of the globe for the period 1905 through 2002. Even though annual precipitation accounts for most of the temporal and spatial variability in annual runoff, increases in temperature have had an increasingly negative effect on annual runoff after 1980. Although the effects of increasing temperature on runoff became more apparent after 1980, the relative magnitude of these effects are small compared to the effects of precipitation on global runoff. ?? 2010 Royal Meteorological Society.

  15. Examining the Relationship between Role Models and Leadership Growth during the Transition to Adulthood (United States)

    Bowers, Jill R.; Rosch, David M.; Collier, Daniel A.


    Leadership and developmental scholars have highlighted the need to enhance youth leadership skills. Yet, research that explains youths' perceptions of how and when role models influences their leadership growth processes is limited. To address these gaps and begin to develop an understanding of youths' perspectives, we employed a qualitative,…

  16. Examination of Bond Properties through Infrared Spectroscopy and Molecular Modeling in the General Chemistry Laboratory (United States)

    Csizmar, Clifford M.; Force, Dee Ann; Warner, Don L.


    A concerted effort has been made to increase the opportunities for undergraduate students to address scientific problems employing the processes used by practicing chemists. As part of this effort, an infrared (IR) spectroscopy and molecular modeling experiment was developed for the first-year general chemistry laboratory course. In the…

  17. Examining Engineering & Technology Students' Acceptance of Network Virtualization Technology Using the Technology Acceptance Model (United States)

    Yousif, Wael K.


    This causal and correlational study was designed to extend the Technology Acceptance Model (TAM) and to test its applicability to Valencia Community College (VCC) Engineering and Technology students as the target user group when investigating the factors influencing their decision to adopt and to utilize VMware as the target technology. In…

  18. Introducing a Model for Optimal Design of Sequential Objective Structured Clinical Examinations (United States)

    Mortaz Hejri, Sara; Yazdani, Kamran; Labaf, Ali; Norcini, John J.; Jalili, Mohammad


    In a sequential OSCE which has been suggested to reduce testing costs, candidates take a short screening test and who fail the test, are asked to take the full OSCE. In order to introduce an effective and accurate sequential design, we developed a model for designing and evaluating screening OSCEs. Based on two datasets from a 10-station…

  19. Examination of Different Item Response Theory Models on Tests Composed of Testlets (United States)

    Kogar, Esin Yilmaz; Kelecioglu, Hülya


    The purpose of this research is to first estimate the item and ability parameters and the standard error values related to those parameters obtained from Unidimensional Item Response Theory (UIRT), bifactor (BIF) and Testlet Response Theory models (TRT) in the tests including testlets, when the number of testlets, number of independent items, and…

  20. A Monte Carlo Examination of an MTMM Model with Planned Incomplete Data Structures. (United States)

    Bunting, Brendan P.; Adamson, Gary; Mulhall, Peter K.


    Studied planned incomplete data designs for the purpose of substantially reducing the amount of data required for multitrait-multimethod models. Simulations studied the effectiveness of Listwise Deletion, Pairwise Deletion, and the expectation maximization (EM) algorithm. Results indicate that EM is generally precise and efficient. (SLD)

  1. Examining the Relations of Time Management and Procrastination within a Model of Self-Regulated Learning (United States)

    Wolters, Christopher A.; Won, Sungjun; Hussain, Maryam


    The primary goal of this study was to investigate whether college students' academic time management could be used to understand their engagement in traditional and active forms of procrastination within a model of self-regulated learning. College students (N = 446) completed a self-report survey that assessed motivational and strategic aspects of…

  2. Examination of the wind speed limit function in the Rothermel surface fire spread model (United States)

    Patricia L. Andrews; Miguel G. Cruz; Richard C. Rothermel


    The Rothermel surface fire spread model includes a wind speed limit, above which predicted rate of spread is constant. Complete derivation of the wind limit as a function of reaction intensity is given, along with an alternate result based on a changed assumption. Evidence indicates that both the original and the revised wind limits are too restrictive. Wind limit is...

  3. A Mixed-Methodological Examination of Investment Model Variables among Abused and Nonabused College Women (United States)

    Dardis, Christina M.; Kelley, Erika L.; Edwards, Katie M.; Gidycz, Christine A.


    Objective: This study assessed abused and nonabused women's perceptions of Investment Model (IM) variables (ie, relationship investment, satisfaction, commitment, quality of alternatives) utilizing a mixed-methods design. Participants: Participants included 102 college women, approximately half of whom were in abusive dating relationships.…

  4. Further Examining Berry’s Model: The Applicability of Latent Profile Analysis to Acculturation (United States)

    Fox, Rina S.; Merz, Erin L.; Solórzano, Martha T.; Roesch, Scott C.


    This study used latent profile analysis (LPA) to identify acculturation profiles. A 3-profile solution fit the data best, and comparisons on demographic and psychosocial outcomes as a function of profile yielded expected results. The findings support using LPA as a parsimonious way to model acculturation without anticipating profiles in advance. PMID:28819336

  5. Further Examining Berry's Model: The Applicability of Latent Profile Analysis to Acculturation (United States)

    Fox, Rina S.; Merz, Erin L.; Solórzano, Martha T.; Roesch, Scott C.


    This study used latent profile analysis (LPA) to identify acculturation profiles. A three-profile solution fit the data best, and comparisons on demographic and psychosocial outcomes as a function of profile yielded expected results. The findings support using LPA as a parsimonious way to model acculturation without anticipating profiles in…

  6. An Econometric Examination of the Behavioral Perspective Model in the Context of Norwegian Retailing (United States)

    Sigurdsson, Valdimar; Kahamseh, Saeed; Gunnarsson, Didrik; Larsen, Nils Magne; Foxall, Gordon R.


    The behavioral perspective model's (BPM; Foxall, 1990) retailing literature is built on extensive empirical research and techniques that were originally refined in choice experiments in behavioral economics and behavior analysis, and then tested mostly on British consumer panel data. We test the BPM in the context of Norwegian retailing. This…

  7. Examining a Causal Model of Early Drug Involvement Among Inner City Junior High School Youths. (United States)

    Dembo, Richard; And Others

    Reflecting the need to construct more inclusive, socially and culturally relevant conceptions of drug use than currently exist, the determinants of drug involvement among inner-city youths within the context of a causal model were investigated. The drug involvement of the Black and Puerto Rican junior high school girls and boys was hypothesized to…

  8. An Alternative Theoretical Model: Examining Psychosocial Identity Development of International Students in the United States (United States)

    Kim, Eunyoung


    Despite the plethora of college student identity development research, very little attention has been paid to the identity formation of international students. Rather than adopting existing identity theories in college student development, this exploratory qualitative study proposes a new psychosocial identity development model for international…

  9. Examining the Mathematical Modeling Processes of Primary School 4th-Grade Students: Shopping Problem (United States)

    Ulu, Mustafa


    The purpose of this study is to identify primary school students' thinking processes within the mathematical modeling process and the challenges they encounter, if any. This is a basic qualitative research study conducted in a primary school in the city of Kütahya in the academic year of 2015-2016. The study group of the research was composed of…

  10. Examining the Simple View of Reading Model for United States High School Spanish Students (United States)

    Sparks, Richard; Patton, Jon


    The Simple View of Reading (SVR) model, which posits that reading comprehension is the product of word decoding and language comprehension that make independent contributions to reading skill, has been found to explain the acquisition of first language (L1) reading and second language (L2) reading in young English language learners (ELLs).…

  11. Using a Structural Equation Model to Examine Factors Affecting Married Individuals' Sexual Embarrassment (United States)

    Celik, Eyup; Arici, Neslihan


    This study aimed to predict the effects of levels of sexual awareness, sexual courage, and sexual self-disclosure on sexual embarrassment. Data was collected from 336 married individuals, who have students in the Sultangazi District of Istanbul. According to the structural equation model (SEM), sexual self-disclosure, directly, and sexual courage…

  12. Examining the determinants of efficiency using a latent class stochastic frontier model

    Directory of Open Access Journals (Sweden)

    Michael Danquah


    Full Text Available In this study, we combine the latent class stochastic frontier model with the complex time decay model to form a single-stage approach that accounts for unobserved technological differences to estimate efficiency and the determinants of efficiency. In this way, we contribute to the literature by estimating “pure” efficiency and determinants of productive units based on the class structure. An application of this proposed model is presented using data on the Ghanaian banking system. Our results show that inefficiency effects on the productive unit are specific to the class structure of the productive unit and therefore assuming a common technology for all productive units as is in the popular Battese and Coelli model used extensively in the literature may be misleading. The study therefore provides useful empirical evidence on the importance of accounting for unobserved technological differences across productive units. A policy based on the identified classes of the productive unit enables a more accurate and effectual measures to address efficiency challenges within the banking industry, thereby promoting financial sector development and economic growth.

  13. Examining the Antecedents of ICT Adoption in Education Using an Extended Technology Acceptance Model (TAM) (United States)

    Teeroovengadum, Viraiyan; Heeraman, Nabeel; Jugurnath, Bhavish


    This study assesses the determinants of ICT adoption by educators in the teaching and learning process in the context of a developing country, Mauritius. A hierarchical regression analysis is used, to firstly determine the incremental effects of factors from the technology acceptance model (TAM) while controlling for demographic variables such as…

  14. A Bidimensional Model of Acculturation for Examining Differences in Family Functioning and Behavior Problems in Hispanic Immigrant Adolescents (United States)

    Sullivan, Summer; Schwartz, Seth J.; Prado, Guillermo; Shi Huang,; Pantin, Hilda; Szapocznik, Jose


    This study examined the relationships of adolescent acculturation orientations to adolescent and parent reports of family functioning and behavior problems in a sample of 338 Hispanic families. Acculturation orientations are derived from the model proposed by Berry. Results indicate that integrated adolescents, who both maintain heritage culture…

  15. Rat Models of Cardiometabolic Diseases: Baseline Clinical Chemistries, and Rationale for their Use in Examining Air Pollution Health Effects (United States)

    This is the first of a series of 8 papers examining susceptibility of various rodent cardiometabolic disease models to ozone induced health effects. Individuals with cardiovascular and metabolic diseases (CVD) are shown to be more susceptible to adverse health effects o...

  16. Experimental model to evaluate in vivo and in vitro cartilage MR imaging by means of histological analyses

    Energy Technology Data Exchange (ETDEWEB)

    Bittersohl, B. [Department of Orthopedic Surgery, University of Berne, Inselspital, 3010 Bern (Switzerland); Mamisch, T.C. [Department of Orthopedic Surgery, University of Berne, Inselspital, 3010 Bern (Switzerland)], E-mail:; Welsch, G.H. [Department of Trauma Surgery, University of Erlangen (Germany); Stratmann, J.; Forst, R. [Department of Orthopedic Surgery, University of Erlangen (Germany); Swoboda, B. [Department of Orthopedic Rheumatology, University of Erlangen (Germany); Bautz, W. [Department of Diagnostic Radiology, University of Erlangen (Germany); Rechenberg, B. von [Musculoskeletal Research Unit (MSRU), University of Zurich (Switzerland); Cavallaro, A. [Department of Diagnostic Radiology, University of Erlangen (Germany)


    Objectives: Implementation of an experimental model to compare cartilage MR imaging by means of histological analyses. Material and methods: MRI was obtained from 4 patients expecting total knee replacement at 1.5 and/or 3 T prior surgery. The timeframe between pre-op MRI and knee replacement was within two days. Resected cartilage-bone samples were tagged with Ethi-pins to reproduce the histological cutting course. Pre-operative scanning at 1.5 T included following parameters for fast low angle shot (FLASH: TR/TE/FA = 33 ms/6 ms/30 deg., BW = 110 kHz, 120 mm x 120 mm FOV, 256 x 256 matrix, 0.65 mm slice-thickness) and double echo steady state (DESS: TR/TE/FA = 23.7 ms/6.9 ms/40 deg., BW = 130 kHz, 120 x 120 mm FOV, 256 x 256 matrix, 0.65 mm slice-thickness). At 3 T, scan parameters were: FLASH (TR/TE/FA = 12.2 ms/5.1 ms/10 deg., BW = 130 kHz, 170 x 170 mm FOV, 320 x 320, 0.5 mm slice-thickness) and DESS (TR/TE/FA = 15.6 ms/4.5 ms/25 deg., BW = 200 kHz, 135 mm x 150 mm FOV, 288 x 320 matrix, 0.5 mm slice-thickness). Imaging of the specimens was done the same day at 1.5 T. MRI (Noyes) and histological (Mankin) score scales were correlated using the paired t-test. Sensitivity and specificity for the detection of different grades of cartilage degeneration were assessed. Inter-reader and intra-reader reliability was determined using Kappa analysis. Results: Low correlation (sensitivity, specificity) was found for both sequences in normal to mild Mankin grades. Only moderate to severe changes were diagnosed with higher significance and specificity. The use of higher field-strengths was advantageous for both protocols with sensitivity values ranging from 13.6% to 93.3% (FLASH) and 20.5% to 96.2% (DESS). Kappa values ranged from 0.488 to 0.944. Conclusions: Correlating MR images with continuous histological slices was feasible by using three-dimensional imaging, multi-planar-reformat and marker pins. The capability of diagnosing early cartilage changes with high accuracy

  17. Examining the antecedents of Facebook acceptance via structural equation modeling: A case of CEGEP students

    Directory of Open Access Journals (Sweden)

    Tenzin Doleck


    Full Text Available Although the last decade has witnessed social networking sites of varied flavors, Facebook’s user growth continues to balloon, and relatedly, Facebook remains popular among the college populace. While there has been a growing body of work on ascertaining antecedents of Facebook use among college students, Collège d'enseignement général et professionnel (CEGEP students’ acceptance of Facebook remains underexplored. The purpose of this study was to analyze CEGEP students’ acceptance of Facebook using the technology acceptance model (TAM. Structural equation modeling was conducted on data from a survey of 214 CEGEP students. We find that Facebook use is motivated by the core TAM constructs as well as the added factors of peer influence, perceived enjoyment, perceived self-efficacy, relative advantage, risk, and trust.

  18. Spatio-Temporal Dynamics in Collective Frog Choruses Examined by Mathematical Modeling and Field Observations (United States)

    Aihara, Ikkyu; Mizumoto, Takeshi; Otsuka, Takuma; Awano, Hiromitsu; Nagira, Kohei; Okuno, Hiroshi G.; Aihara, Kazuyuki


    This paper reports theoretical and experimental studies on spatio-temporal dynamics in the choruses of male Japanese tree frogs. First, we theoretically model their calling times and positions as a system of coupled mobile oscillators. Numerical simulation of the model as well as calculation of the order parameters show that the spatio-temporal dynamics exhibits bistability between two-cluster antisynchronization and wavy antisynchronization, by assuming that the frogs are attracted to the edge of a simple circular breeding site. Second, we change the shape of the breeding site from the circle to rectangles including a straight line, and evaluate the stability of two-cluster and wavy antisynchronization. Numerical simulation shows that two-cluster antisynchronization is more frequently observed than wavy antisynchronization. Finally, we recorded frog choruses at an actual paddy field using our sound-imaging method. Analysis of the video demonstrated a consistent result with the aforementioned simulation: namely, two-cluster antisynchronization was more frequently realized.

  19. Encouraging IS developers to learn business skills: an examination of the MARS model


    Tsay, Han-Huei (Crystal)


    Though prior research has recognized business skills as one of the keys to successful information system development, few studies have investigated the determinants of an IS developer’s behavioral intention to learn such skills. Based on the Motivation–Ability–Role Perception–Situational factors (i.e., the MARS model), this study argues that the intention of IS developers to acquire business skills is influenced by learning motivation (M), learning self-efficacy (A), change agent role percept...



    Saraçlı, Sinan; KESKINTURK, Timur; CİCEK, Mukades; GAZELOGLU, Cengiz


    Earlier studies on motivation have all showed that there is a strong correlation between the organizational commitments and motivations of the workers. The purpose of this study is to investigate the effects of organizational commitment on individual’s extrinsic and intrinsic motivation which are effective factors of job motivation. With this purpose Explanatory Factor Analysis and Structural Equation Modelling (SEM) used to determine the effects of three sub factors of organizational commitm...