WorldWideScience

Sample records for model originally proposed

  1. Controlling Decoherence in Superconducting Qubits: Phenomenological Model and Microscopic Origin of 1/f Noise

    Science.gov (United States)

    2011-04-28

    quasiparticle poisoning which include a completely novel physical origin of these noises. We also proposed a model for excess low frequency flux noise which...and quasiparticle poisoning which include a completely novel physical origin of these noises. We also proposed a model for excess low frequency flux...metallic nanomechanical resonators, Phys. Rev. B 81, 184112 (2010). 3) L. Faoro, A. Kitaev and L. B. Ioffe, Quasiparticle poisoning and Josephson current

  2. A Proposal for a Flexible Trend Specification in DSGE Models

    Directory of Open Access Journals (Sweden)

    Slanicay Martin

    2016-06-01

    Full Text Available In this paper I propose a flexible trend specification for estimating DSGE models on log differences. I demonstrate this flexible trend specification on a New Keynesian DSGE model of two economies, which I consequently estimate on data from the Czech economy and the euro area, using Bayesian techniques. The advantage of the trend specification proposed is that the trend component and the cyclical component are modelled jointly in a single model. The proposed trend specification is flexible in the sense that smoothness of the trend can be easily modified by different calibration of some of the trend parameters. The results suggest that this method is capable of finding a very reasonable trend in the data. Moreover, comparison of forecast performance reveals that the proposed specification offers more reliable forecasts than the original variant of the model.

  3. Origin of holographic dark energy models

    International Nuclear Information System (INIS)

    Myung, Yun Soo; Seo, Min-Gyun

    2009-01-01

    We investigate the origin of holographic dark energy models which were recently proposed to explain the dark energy-dominated universe. For this purpose, we introduce the spacetime foam uncertainty of δl≥l p α l α-1 . It was argued that the case of α=2/3 could describe the dark energy with infinite statistics, while the case of α=1/2 can describe the ordinary matter with Bose-Fermi statistics. However, two cases may lead to the holographic energy density if the latter recovers from the geometric mean of UV and IR scales. Hence the dark energy with infinite statistics based on the entropy bound is not an ingredient for deriving the holographic dark energy model. Furthermore, it is shown that the agegraphic dark energy models are the holographic dark energy model with different IR length scales

  4. Tacit knowledge in academia: a proposed model and measurement scale.

    Science.gov (United States)

    Leonard, Nancy; Insch, Gary S

    2005-11-01

    The authors propose a multidimensional model of tacit knowledge and develop a measure of tacit knowledge in academia. They discuss the theory and extant literature on tacit knowledge and propose a 6-factor model. Experiment 1 is a replication of a recent study of academic tacit knowledge using the scale developed and administered at an Israeli university (A. Somech & R. Bogler, 1999). The results of the replication differed from those found in the original study. For Experiment 2, the authors developed a domain-specific measure of academic tacit knowledge, the Academic Tacit Knowledge Scale (ATKS), and used this measure to explore the multidimensionality of tacit knowledge proposed in the model. The results of an exploratory factor analysis (n=142) followed by a confirmatory factor analysis (n=286) are reported. The sample for both experiments was 428 undergraduate students enrolled at a large public university in the eastern United States. Results indicated that a 5-factor model of academic tacit knowledge provided a strong fit for the data.

  5. Thematic Apperception Test: an original proposal for interaction analysis

    Directory of Open Access Journals (Sweden)

    Doriana Dipaola

    2015-12-01

    Full Text Available The TAT as projective technique gives the opportunity to explore the inner world and the intra-psychic functioning, as well as the objectual representations and the prevailing thinking processes. Our hypothesis is that the TAT could also be deployed as a valid tool in the analysis of inter-personal functioning, specifically within the couple. From this assumption originates our proposal for an original methodology of TAT deployment and reading, which integrates the classical individual TAT methodology with the Common Rorschach method suggested by Willi. The goal is to experiment a parallel utilisation of the test that could contribute to the understanding of personalities and of how these intertwine in couple interaction. “In the relationship with the partner, the personality takes new shapes, given personality and character traits are strengthened, while others lose importance”, (Theodore Lidz, in Willi, 1990. The couple TAT presupposes a sequence of pictures proposed following procedures identical to the Common Rorschach ones to the single individuals at first and then to the couple. From the initial individual task follows the one of building a commonly shared history starting from the stimulus. The suggested methodology shall be exemplified through the presentation of clinical cases belonging to the research sample. The comprehension of the inter-personal dynamic, in a common task, could allow to explore the ways in which conflict expresses itself, the roles and prospects for collaboration, the “generativity” of the couple and the management of affects and anxieties in the interaction and could be successfully deployed as a tool in the context of couple counselling.

  6. An original piecewise model for computing energy expenditure from accelerometer and heart rate signals.

    Science.gov (United States)

    Romero-Ugalde, Hector M; Garnotel, M; Doron, M; Jallon, P; Charpentier, G; Franc, S; Huneker, E; Simon, C; Bonnet, S

    2017-07-28

    Activity energy expenditure (EE) plays an important role in healthcare, therefore, accurate EE measures are required. Currently available reference EE acquisition methods, such as doubly labeled water and indirect calorimetry, are complex, expensive, uncomfortable, and/or difficult to apply on real time. To overcome these drawbacks, the goal of this paper is to propose a model for computing EE in real time (minute-by-minute) from heart rate and accelerometer signals. The proposed model, which consists of an original branched model, uses heart rate signals for computing EE on moderate to vigorous physical activities and a linear combination of heart rate and counts per minute for computing EE on light to moderate physical activities. Model parameters were estimated from a given data set composed of 53 subjects performing 25 different physical activities (light-, moderate- and vigorous-intensity), and validated using leave-one-subject-out. A different database (semi-controlled in-city circuit), was used in order to validate the versatility of the proposed model. Comparisons are done versus linear and nonlinear models, which are also used for computing EE from accelerometer and/or HR signals. The proposed piecewise model leads to more accurate EE estimations ([Formula: see text], [Formula: see text] and [Formula: see text] J kg -1 min -1 and [Formula: see text], [Formula: see text], and [Formula: see text] J kg -1 min -1 on each validation database). This original approach, which is more conformable and less expensive than the reference methods, allows accurate EE estimations, in real time (minute-by-minute), during a large variety of physical activities. Therefore, this model may be used on applications such as computing the time that a given subject spent on light-intensity physical activities and on moderate to vigorous physical activities (binary classification accuracy of 0.8155).

  7. A Compound Model for the Origin of Earth's Water

    Science.gov (United States)

    Izidoro, A.; de Souza Torres, K.; Winter, O. C.; Haghighipour, N.

    2013-04-01

    One of the most important subjects of debate in the formation of the solar system is the origin of Earth's water. Comets have long been considered as the most likely source of the delivery of water to Earth. However, elemental and isotopic arguments suggest a very small contribution from these objects. Other sources have also been proposed, among which local adsorption of water vapor onto dust grains in the primordial nebula and delivery through planetesimals and planetary embryos have become more prominent. However, no sole source of water provides a satisfactory explanation for Earth's water as a whole. In view of that, using numerical simulations, we have developed a compound model incorporating both the principal endogenous and exogenous theories, and investigating their implications for terrestrial planet formation and water delivery. Comets are also considered in the final analysis, as it is likely that at least some of Earth's water has cometary origin. We analyze our results comparing two different water distribution models, and complement our study using the D/H ratio, finding possible relative contributions from each source and focusing on planets formed in the habitable zone. We find that the compound model plays an important role by showing greater advantage in the amount and time of water delivery in Earth-like planets.

  8. A COMPOUND MODEL FOR THE ORIGIN OF EARTH'S WATER

    International Nuclear Information System (INIS)

    Izidoro, A.; Winter, O. C.; De Souza Torres, K.; Haghighipour, N.

    2013-01-01

    One of the most important subjects of debate in the formation of the solar system is the origin of Earth's water. Comets have long been considered as the most likely source of the delivery of water to Earth. However, elemental and isotopic arguments suggest a very small contribution from these objects. Other sources have also been proposed, among which local adsorption of water vapor onto dust grains in the primordial nebula and delivery through planetesimals and planetary embryos have become more prominent. However, no sole source of water provides a satisfactory explanation for Earth's water as a whole. In view of that, using numerical simulations, we have developed a compound model incorporating both the principal endogenous and exogenous theories, and investigating their implications for terrestrial planet formation and water delivery. Comets are also considered in the final analysis, as it is likely that at least some of Earth's water has cometary origin. We analyze our results comparing two different water distribution models, and complement our study using the D/H ratio, finding possible relative contributions from each source and focusing on planets formed in the habitable zone. We find that the compound model plays an important role by showing greater advantage in the amount and time of water delivery in Earth-like planets.

  9. The Halo Model of Origin Images

    DEFF Research Database (Denmark)

    Josiassen, Alexander; Lukas, Bryan A.; Whitwell, Gregory J.

    2013-01-01

    National origin has gained importance as a marketing tool for practitioners to sell their goods and services. However, because origin-image research has been troubled by several fundamental limitations, academia has become sceptical of the current status and strategic implications of the concept....... The aim of this paper was threefold, namely, to provide a state-of-the-art review of origin-image research in marketing, develop and empirically test a new origin-image model and, present the implications of the study....

  10. Origin-Dependent Inverted-Repeat Amplification: Tests of a Model for Inverted DNA Amplification.

    Directory of Open Access Journals (Sweden)

    Bonita J Brewer

    2015-12-01

    Full Text Available DNA replication errors are a major driver of evolution--from single nucleotide polymorphisms to large-scale copy number variations (CNVs. Here we test a specific replication-based model to explain the generation of interstitial, inverted triplications. While no genetic information is lost, the novel inversion junctions and increased copy number of the included sequences create the potential for adaptive phenotypes. The model--Origin-Dependent Inverted-Repeat Amplification (ODIRA-proposes that a replication error at pre-existing short, interrupted, inverted repeats in genomic sequences generates an extrachromosomal, inverted dimeric, autonomously replicating intermediate; subsequent genomic integration of the dimer yields this class of CNV without loss of distal chromosomal sequences. We used a combination of in vitro and in vivo approaches to test the feasibility of the proposed replication error and its downstream consequences on chromosome structure in the yeast Saccharomyces cerevisiae. We show that the proposed replication error-the ligation of leading and lagging nascent strands to create "closed" forks-can occur in vitro at short, interrupted inverted repeats. The removal of molecules with two closed forks results in a hairpin-capped linear duplex that we show replicates in vivo to create an inverted, dimeric plasmid that subsequently integrates into the genome by homologous recombination, creating an inverted triplication. While other models have been proposed to explain inverted triplications and their derivatives, our model can also explain the generation of human, de novo, inverted amplicons that have a 2:1 mixture of sequences from both homologues of a single parent--a feature readily explained by a plasmid intermediate that arises from one homologue and integrates into the other homologue prior to meiosis. Our tests of key features of ODIRA lend support to this mechanism and suggest further avenues of enquiry to unravel the origins

  11. Origin-Dependent Inverted-Repeat Amplification: Tests of a Model for Inverted DNA Amplification.

    Science.gov (United States)

    Brewer, Bonita J; Payen, Celia; Di Rienzi, Sara C; Higgins, Megan M; Ong, Giang; Dunham, Maitreya J; Raghuraman, M K

    2015-12-01

    DNA replication errors are a major driver of evolution--from single nucleotide polymorphisms to large-scale copy number variations (CNVs). Here we test a specific replication-based model to explain the generation of interstitial, inverted triplications. While no genetic information is lost, the novel inversion junctions and increased copy number of the included sequences create the potential for adaptive phenotypes. The model--Origin-Dependent Inverted-Repeat Amplification (ODIRA)-proposes that a replication error at pre-existing short, interrupted, inverted repeats in genomic sequences generates an extrachromosomal, inverted dimeric, autonomously replicating intermediate; subsequent genomic integration of the dimer yields this class of CNV without loss of distal chromosomal sequences. We used a combination of in vitro and in vivo approaches to test the feasibility of the proposed replication error and its downstream consequences on chromosome structure in the yeast Saccharomyces cerevisiae. We show that the proposed replication error-the ligation of leading and lagging nascent strands to create "closed" forks-can occur in vitro at short, interrupted inverted repeats. The removal of molecules with two closed forks results in a hairpin-capped linear duplex that we show replicates in vivo to create an inverted, dimeric plasmid that subsequently integrates into the genome by homologous recombination, creating an inverted triplication. While other models have been proposed to explain inverted triplications and their derivatives, our model can also explain the generation of human, de novo, inverted amplicons that have a 2:1 mixture of sequences from both homologues of a single parent--a feature readily explained by a plasmid intermediate that arises from one homologue and integrates into the other homologue prior to meiosis. Our tests of key features of ODIRA lend support to this mechanism and suggest further avenues of enquiry to unravel the origins of interstitial

  12. The Associative Basis of Scientific Creativity: A Model Proposal

    Directory of Open Access Journals (Sweden)

    Esra Kanli

    2014-06-01

    Full Text Available Creativity is accepted as an important part of scientific skills. Scientific creativity proceeds from a need or urge to solve a problem, and in-volves the production of original and useful ideas or products. Existing scientific creativity theories and tests do not feature the very im-portant thinking processes, such as analogical and associative thinking, which can be consid-ered crucial in creative scientific problem solv-ing. Current study’s aim is to provide an alter-native model and explicate the associative basis of scientific creativity. Emerging from the re-viewed theoretical framework, Scientific Asso-ciations Model is proposed. This model claims that, similarity and mediation constitutes the basis of creativity and focuses on three compo-nents namely; associative thinking, analogical thinking (analogical reasoning & analogical problem solving and insight which are consid-ered to be main elements of scientific associa-tive thinking.

  13. Modern human origins: progress and prospects.

    OpenAIRE

    Stringer, Chris

    2002-01-01

    The question of the mode of origin of modern humans (Homo sapiens) has dominated palaeoanthropological debate over the last decade. This review discusses the main models proposed to explain modern human origins, and examines relevant fossil evidence from Eurasia, Africa and Australasia. Archaeological and genetic data are also discussed, as well as problems with the concept of 'modernity' itself. It is concluded that a recent African origin can be supported for H. sapiens, morphologically, be...

  14. A Fovea Localization Scheme Using Vessel Origin-Based Parabolic Model

    Directory of Open Access Journals (Sweden)

    Chun-Yuan Yu

    2014-09-01

    Full Text Available At the center of the macula, fovea plays an important role in computer-aided diagnosis. To locate the fovea, this paper proposes a vessel origin (VO-based parabolic model, which takes the VO as the vertex of the parabola-like vasculature. Image processing steps are applied to accurately locate the fovea on retinal images. Firstly, morphological gradient and the circular Hough transform are used to find the optic disc. The structure of the vessel is then segmented with the line detector. Based on the characteristics of the VO, four features of VO are extracted, following the Bayesian classification procedure. Once the VO is identified, the VO-based parabolic model will locate the fovea. To find the fittest parabola and the symmetry axis of the retinal vessel, an Shift and Rotation (SR-Hough transform that combines the Hough transform with the shift and rotation of coordinates is presented. Two public databases of retinal images, DRIVE and STARE, are used to evaluate the proposed method. The experiment results show that the average Euclidean distances between the located fovea and the fovea marked by experts in two databases are 9.8 pixels and 30.7 pixels, respectively. The results are stronger than other methods and thus provide a better macular detection for further disease discovery.

  15. The origins of originality: the neural bases of creative thinking and originality.

    Science.gov (United States)

    Shamay-Tsoory, S G; Adler, N; Aharon-Peretz, J; Perry, D; Mayseless, N

    2011-01-01

    Although creativity has been related to prefrontal activity, recent neurological case studies postulate that patients who have left frontal and temporal degeneration involving deterioration of language abilities may actually develop de novo artistic abilities. In this study, we propose a neural and cognitive model according to which a balance between the two hemispheres affects a major aspect of creative cognition, namely, originality. In order to examine the neural basis of originality, that is, the ability to produce statistically infrequent ideas, patients with localized lesions in the medial prefrontal cortex (mPFC), inferior frontal gyrus (IFG), and posterior parietal and temporal cortex (PC), were assessed by two tasks involving divergent thinking and originality. Results indicate that lesions in the mPFC involved the most profound impairment in originality. Furthermore, precise anatomical mapping of lesions indicated that while the extent of lesion in the right mPFC was associated with impaired originality, lesions in the left PC were associated with somewhat elevated levels of originality. A positive correlation between creativity scores and left PC lesions indicated that the larger the lesion is in this area the greater the originality. On the other hand, a negative correlation was observed between originality scores and lesions in the right mPFC. It is concluded that the right mPFC is part of a right fronto-parietal network which is responsible for producing original ideas. It is possible that more linear cognitive processing such as language, mediated by left hemisphere structures interferes with creative cognition. Therefore, lesions in the left hemisphere may be associated with elevated levels of originality. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Proposal for an ecoradiological centre model

    International Nuclear Information System (INIS)

    Perovic, S.M.; Zunic, Z.; Demajo, M.; Konjevic, N.

    1998-01-01

    The problem of establishing an optimal Ecoradiological Centre Model is studied in some detail for the town of Kotor which is under the protection of the World Cultural and Natural Heritage. The proposed structure of the Centre is analyzed from the view of Engineering, Education and Scientific parameters. This Model is suitable for implementation as a network Centre Model for the state of Montenegro. Further, the modelling strategy of the ecoradiological condition control of natural, construction, bio and technological systems is elaborated. The proposal includes the ecoradiological monitoring, radioactive and electromagnetic radiation processing and protection for different natural zones as well as their different geostructures, aerial and hydrogeological conditions. The programme also includes all housing objects (hotels, flats, houses, office premises etc.). Here will also be presented the radiation protection and recommendations for the implementation of Title VII of the European Basic Safety Standards Directive (BSS), concerning significant increase in exposure due to natural radiation sources. Also, the proposal of Local Radiation Protection for the town of Kotor is presented. Our proposal for an Ecoradiological Centre Model presented here is in a form of a pilot programme, applicable also for other towns and states. (author)

  17. Origin, development, and evolution of butterfly eyespots.

    Science.gov (United States)

    Monteiro, Antónia

    2015-01-07

    This article reviews the latest developments in our understanding of the origin, development, and evolution of nymphalid butterfly eyespots. Recent contributions to this field include insights into the evolutionary and developmental origin of eyespots and their ancestral deployment on the wing, the evolution of eyespot number and eyespot sexual dimorphism, and the identification of genes affecting eyespot development and black pigmentation. I also compare features of old and more recently proposed models of eyespot development and propose a schematic for the genetic regulatory architecture of eyespots. Using this schematic I propose two hypotheses for why we observe limits to morphological diversity across these serially homologous traits.

  18. A new proposal concerning the botanical origin of Baltic amber.

    Science.gov (United States)

    Wolfe, Alexander P; Tappert, Ralf; Muehlenbachs, Karlis; Boudreau, Marc; McKellar, Ryan C; Basinger, James F; Garrett, Amber

    2009-10-07

    Baltic amber constitutes the largest known deposit of fossil plant resin and the richest repository of fossil insects of any age. Despite a remarkable legacy of archaeological, geochemical and palaeobiological investigation, the botanical origin of this exceptional resource remains controversial. Here, we use taxonomically explicit applications of solid-state Fourier-transform infrared (FTIR) microspectroscopy, coupled with multivariate clustering and palaeobotanical observations, to propose that conifers of the family Sciadopityaceae, closely allied to the sole extant representative, Sciadopitys verticillata, were involved in the genesis of Baltic amber. The fidelity of FTIR-based chemotaxonomic inferences is upheld by modern-fossil comparisons of resins from additional conifer families and genera (Cupressaceae: Metasequoia; Pinaceae: Pinus and Pseudolarix). Our conclusions challenge hypotheses advocating members of either of the families Araucariaceae or Pinaceae as the primary amber-producing trees and correlate favourably with the progressive demise of subtropical forest biomes from northern Europe as palaeotemperatures cooled following the Eocene climate optimum.

  19. Evaluation of six NEHRP B/C crustal amplification models proposed for use in western North America

    Science.gov (United States)

    Boore, David; Campbell, Kenneth W.

    2016-01-01

    We evaluate six crustal amplification models based on National Earthquake Hazards Reduction Program (NEHRP) B/C crustal profiles proposed for use in western North America (WNA) and often used in other active crustal regions where crustal properties are unknown. One of the models is based on an interpolation of generic rock velocity profiles previously proposed for WNA and central and eastern North America (CENA), in conjunction with material densities based on an updated velocity–density relationship. A second model is based on the velocity profile used to develop amplification factors for the Next Generation Attenuation (NGA)‐West2 project. A third model is based on a near‐surface velocity profile developed from the NGA‐West2 site database. A fourth model is based on velocity and density profiles originally proposed for use in CENA but recently used to represent crustal properties in California. We propose two alternatives to this latter model that more closely represent WNA crustal properties. We adopt a value of site attenuation (κ0) for each model that is either recommended by the author of the model or proposed by us. Stochastic simulation is used to evaluate the Fourier amplification factors and their impact on response spectra associated with each model. Based on this evaluation, we conclude that among the available models evaluated in this study the NEHRP B/C amplification model of Boore (2016) best represents median crustal amplification in WNA, although the amplification models based on the crustal profiles of Kamai et al. (2013, 2016, unpublished manuscript, see Data and Resources) and Yenier and Atkinson (2015), the latter adjusted to WNA crustal properties, can be used to represent epistemic uncertainty.

  20. Proposed Reliability/Cost Model

    Science.gov (United States)

    Delionback, L. M.

    1982-01-01

    New technique estimates cost of improvement in reliability for complex system. Model format/approach is dependent upon use of subsystem cost-estimating relationships (CER's) in devising cost-effective policy. Proposed methodology should have application in broad range of engineering management decisions.

  1. A model-building approach to the origin of flavor

    Energy Technology Data Exchange (ETDEWEB)

    Schumacher, Erik

    2017-01-24

    In this thesis we link the recent anomalies reported in B meson and h→μτ decays to the smallness of neutrino masses and aspects of the flavor puzzle, including the hierarchy of the Yukawa couplings and the disparate fermion mixings. By formulating various new models we attempt to shed light on the potential common origin of the distinct measurements in the flavor sector. To this end, discrete symmetries are utilized in this work as the governing principle behind all fermion interactions. The first two models based on the S{sub 3} and the A{sub 4} symmetry, respectively, aim to unify the diverse fermion masses and mixings. Special features separate the frameworks from the flavor models in the literature that often lack testable predictions. While the first model provides interesting flavor-violating signatures in top quark decays, the second one ties the flavor to the grand unification scale in a novel way. In the three following models we focus on the anomalies that hint at lepton flavor and universality violation. We propose that the large flavor violation observed in h→μτ decays is dictated by the scalar mixing of an enlarged S{sub 4}-symmetric Higgs sector. By constructing two leptoquark models we show for the first time that leptoquark couplings shaped by a Froggatt-Nielsen mechanism can accommodate the B meson anomalies and simultaneously generate naturally-small neutrino masses. Emphasizing the importance of testability, we demonstrate how these models can be probed by future diphoton resonances, using the recent 750 GeV excess as an example scenario.

  2. Evaluation of the existing triple point path models with new experimental data: proposal of an original empirical formulation

    Science.gov (United States)

    Boutillier, J.; Ehrhardt, L.; De Mezzo, S.; Deck, C.; Magnan, P.; Naz, P.; Willinger, R.

    2018-03-01

    With the increasing use of improvised explosive devices (IEDs), the need for better mitigation, either for building integrity or for personal security, increases in importance. Before focusing on the interaction of the shock wave with a target and the potential associated damage, knowledge must be acquired regarding the nature of the blast threat, i.e., the pressure-time history. This requirement motivates gaining further insight into the triple point (TP) path, in order to know precisely which regime the target will encounter (simple reflection or Mach reflection). Within this context, the purpose of this study is to evaluate three existing TP path empirical models, which in turn are used in other empirical models for the determination of the pressure profile. These three TP models are the empirical function of Kinney, the Unified Facilities Criteria (UFC) curves, and the model of the Natural Resources Defense Council (NRDC). As discrepancies are observed between these models, new experimental data were obtained to test their reliability and a new promising formulation is proposed for scaled heights of burst ranging from 24.6-172.9 cm/kg^{1/3}.

  3. Information Systems Success In Public Administration: Proposal For An Exploratory Model

    Directory of Open Access Journals (Sweden)

    Deyvison de Lima Oliveira

    2015-12-01

    Full Text Available Investments in Information Systems (IS have been significantly increasing and hence the relevance of the studies on the IS success is persistent. Delone and Mclean (2003 developed an IS successful model which is a benchmark for researches in the area, however, in the perspective of the public sector, studies are still rare. In this research it was sought to propose an exploratory model of successful IS in public administration, from the identification of each construct items of the Delone and McLean (2003 original model, through multiple case studies in three Municipalities and a Town Hall of the Southern Cone of Rondônia state, in Brazil. Based on the empirical research, it was found that the IS success factors in municipal public administration are close to those factors indicated in the reviewed literature, however, showing some particularities of the public sector. A model of successful factors and items of IS, from the confrontation between literature and empirical data, is presented in the end of this work.

  4. A Proposed Conceptual Model of Military Medical Readiness

    National Research Council Canada - National Science Library

    Van Hall, Brian M

    2007-01-01

    .... The basis for the proposed conceptual model builds on common and accepted latent variable and theoretical modeling techniques proposed by healthcare scholars, organizational theorists, mathematical...

  5. Modeling X-linked ancestral origins in multiparental populations

    NARCIS (Netherlands)

    Zheng, Chaozhi

    2015-01-01

    The models for the mosaic structure of an individual's genome from multiparental populations have been developed primarily for autosomes, whereas X chromosomes receive very little attention. In this paper, we extend our previous approach to model ancestral origin processes along two X chromosomes

  6. Introductory Biology Students’ Conceptual Models and Explanations of the Origin of Variation

    Science.gov (United States)

    Shaw, Neil; Momsen, Jennifer; Reinagel, Adam; Le, Paul; Taqieddin, Ranya; Long, Tammy

    2014-01-01

    Mutation is the key molecular mechanism generating phenotypic variation, which is the basis for evolution. In an introductory biology course, we used a model-based pedagogy that enabled students to integrate their understanding of genetics and evolution within multiple case studies. We used student-generated conceptual models to assess understanding of the origin of variation. By midterm, only a small percentage of students articulated complete and accurate representations of the origin of variation in their models. Targeted feedback was offered through activities requiring students to critically evaluate peers’ models. At semester's end, a substantial proportion of students significantly improved their representation of how variation arises (though one-third still did not include mutation in their models). Students’ written explanations of the origin of variation were mostly consistent with their models, although less effective than models in conveying mechanistic reasoning. This study contributes evidence that articulating the genetic origin of variation is particularly challenging for learners and may require multiple cycles of instruction, assessment, and feedback. To support meaningful learning of the origin of variation, we advocate instruction that explicitly integrates multiple scales of biological organization, assessment that promotes and reveals mechanistic and causal reasoning, and practice with explanatory models with formative feedback. PMID:25185235

  7. Model FRBR in origin

    Directory of Open Access Journals (Sweden)

    Kátia Lúcia Pacheco

    2015-11-01

    Full Text Available Objective. This article aims at identifying the genesis of the studies the conceptual model Functional Requirements for Bibliographic Records (FRBR, published in 1998 by the International Federation of Library Associations and Institutions (IFLA with the proposal to develop new approach to the bibliographic record. Method. For this appealed to bibliographical research, primarily the sources of official information IFLA, in order to investigate the trajectory preceding the publication of the model and determine the intellectual debate on its elaboration. Results. It was found that the FRBR model was born with eminently practical purposes and generates a set of expectations about the reduction of cataloging costs, indicating a minimum level element in bibliographic records that meet the needs of the users associated with the various types of materials and contexts of use. Conclusions. The accumulation of scientific knowledge coupled with sustained and brought experiential dimension in the model, changes the paradigms of traditional cataloging, but model the final report does not present the foundations that support it.

  8. The origin of the vertebrate skeleton

    Science.gov (United States)

    Pivar, Stuart

    2011-01-01

    The anatomy of the human and other vertebrates has been well described since the days of Leonardo da Vinci and Vesalius. The causative origin of the configuration of the bones and of their shapes and forms has been addressed over the ensuing centuries by such outstanding investigators as Goethe, Von Baer, Gegenbauer, Wilhelm His and D'Arcy Thompson, who sought to apply mechanical principles to morphogenesis. However, no coherent causative model of morphogenesis has ever been presented. This paper presents a causative model for the origin of the vertebrate skeleton, based on the premise that the body is a mosaic enlargement of self-organized patterns engrained in the membrane of the egg cell. Drawings illustrate the proposed hypothetical origin of membrane patterning and the changes in the hydrostatic equilibrium of the cytoplasm that cause topographical deformations resulting in the vertebrate body form.

  9. Molecular recognition of the environment and mechanisms of the origin of species in quantum-like modeling of evolution.

    Science.gov (United States)

    Melkikh, Alexey V; Khrennikov, Andrei

    2017-11-01

    A review of the mechanisms of speciation is performed. The mechanisms of the evolution of species, taking into account the feedback of the state of the environment and mechanisms of the emergence of complexity, are considered. It is shown that these mechanisms, at the molecular level, cannot work steadily in terms of classical mechanics. Quantum mechanisms of changes in the genome, based on the long-range interaction potential between biologically important molecules, are proposed as one of possible explanation. Different variants of interactions of the organism and environment based on molecular recognition and leading to new species origins are considered. Experiments to verify the model are proposed. This bio-physical study is completed by the general operational model of based on quantum information theory. The latter is applied to model of epigenetic evolution. We briefly present the basics of the quantum-like approach to modeling of bio-informational processes. This approach is illustrated by the quantum-like model of epigenetic evolution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Proposed evaluation framework for assessing operator performance with multisensor displays

    Science.gov (United States)

    Foyle, David C.

    1992-01-01

    Despite aggressive work on the development of sensor fusion algorithms and techniques, no formal evaluation procedures have been proposed. Based on existing integration models in the literature, an evaluation framework is developed to assess an operator's ability to use multisensor, or sensor fusion, displays. The proposed evaluation framework for evaluating the operator's ability to use such systems is a normative approach: The operator's performance with the sensor fusion display can be compared to the models' predictions based on the operator's performance when viewing the original sensor displays prior to fusion. This allows for the determination as to when a sensor fusion system leads to: 1) poorer performance than one of the original sensor displays (clearly an undesirable system in which the fused sensor system causes some distortion or interference); 2) better performance than with either single sensor system alone, but at a sub-optimal (compared to the model predictions) level; 3) optimal performance (compared to model predictions); or, 4) super-optimal performance, which may occur if the operator were able to use some highly diagnostic 'emergent features' in the sensor fusion display, which were unavailable in the original sensor displays. An experiment demonstrating the usefulness of the proposed evaluation framework is discussed.

  11. NACP Site: Terrestrial Biosphere Model Output Data in Original Format

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains the original model output data submissions from the 24 terrestrial biosphere models (TBM) that participated in the North American...

  12. NACP Site: Terrestrial Biosphere Model Output Data in Original Format

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the original model output data submissions from the 24 terrestrial biosphere models (TBM) that participated in the North American Carbon...

  13. Internet governance origins, current issues, and future possibilities

    CERN Document Server

    Balleste, Roy

    2015-01-01

    Internet Governance: Origins, Current Issues, and Future Possibilities provides an introductory, multidisciplinary account of the forces at work in the evolving concept of internet governance and includes computer history, Internet beginnings, institutions and stakeholders, proposed models of governance, and human rights.

  14. A proposed centralised distribution model for the South African automotive component industry

    Directory of Open Access Journals (Sweden)

    Micheline J. Naude

    2009-12-01

    Full Text Available Purpose: This article explores the possibility of developing a distribution model, similar to the model developed and implemented by the South African pharmaceutical industry, which could be implemented by automotive component manufacturers for supply to independent retailers. Problem Investigated: The South African automotive components distribution chain is extensive with a number of players of varying sizes, from the larger spares distribution groups to a number of independent retailers. Distributing to the smaller independent retailers is costly for the automotive component manufacturers. Methodology: This study is based on a preliminary study of an explorative nature. Interviews were conducted with a senior staff member from a leading automotive component manufacturer in KwaZulu Natal and nine participants at a senior management level at five of their main customers (aftermarket retailers. Findings: The findings from the empirical study suggest that the aftermarket component industry is mature with the role players well established. The distribution chain to the independent retailer is expensive in terms of transaction and distribution costs for the automotive component manufacturer. A proposed centralised distribution model for supply to independent retailers has been developed which should reduce distribution costs for the automotive component manufacturer in terms of (1 the lowest possible freight rate; (2 timely and controlled delivery; and (3 reduced congestion at the customer's receiving dock. Originality: This research is original in that it explores the possibility of implementing a centralised distribution model for independent retailers in the automotive component industry. Furthermore, there is a dearth of published research on the South African automotive component industry particularly addressing distribution issues. Conclusion: The distribution model as suggested is a practical one and should deliver added value to automotive

  15. Original Framework for Optimizing Hybrid Energy Supply

    Directory of Open Access Journals (Sweden)

    Amevi Acakpovi

    2016-01-01

    Full Text Available This paper proposes an original framework for optimizing hybrid energy systems. The recent growth of hybrid energy systems in remote areas across the world added to the increasing cost of renewable energy has triggered the inevitable development of hybrid energy systems. Hybrid energy systems always pose a problem of optimization of cost which has been approached with different perspectives in the recent past. This paper proposes a framework to guide the techniques of optimizing hybrid energy systems in general. The proposed framework comprises four stages including identification of input variables for energy generation, establishment of models of energy generation by individual sources, development of artificial intelligence, and finally summation of selected sources. A case study of a solar, wind, and hydro hybrid system was undertaken with a linear programming approach. Substantial results were obtained with regard to how load requests were constantly satisfied while minimizing the cost of electricity. The developed framework gained its originality from the fact that it has included models of individual sources of energy that even make the optimization problem more complex. This paper also has impacts on the development of policies which will encourage the integration and development of renewable energies.

  16. A wide low-mass binary model for the origin of axially symmetric non-thermal radio sources

    International Nuclear Information System (INIS)

    Kool, M. de; Heuvel, E.P.J. van den

    1985-01-01

    An accreting binary model has been proposed by recent workers to account for the origin of the axially symmetric non-thermal radio sources. The authors show that the only type of binary system that can produce the observed structural properties, is a relatively wide neutron star binary, in which the companion of the neutron star is a low-mass giant. Binaries of this type are expected to resemble closely the eight brightest galactic bulge X-ray sources as well as the progenitors of the two wide radio pulsar binaries. (U.K.)

  17. Introductory biology students' conceptual models and explanations of the origin of variation.

    Science.gov (United States)

    Speth, Elena Bray; Shaw, Neil; Momsen, Jennifer; Reinagel, Adam; Le, Paul; Taqieddin, Ranya; Long, Tammy

    2014-01-01

    Mutation is the key molecular mechanism generating phenotypic variation, which is the basis for evolution. In an introductory biology course, we used a model-based pedagogy that enabled students to integrate their understanding of genetics and evolution within multiple case studies. We used student-generated conceptual models to assess understanding of the origin of variation. By midterm, only a small percentage of students articulated complete and accurate representations of the origin of variation in their models. Targeted feedback was offered through activities requiring students to critically evaluate peers' models. At semester's end, a substantial proportion of students significantly improved their representation of how variation arises (though one-third still did not include mutation in their models). Students' written explanations of the origin of variation were mostly consistent with their models, although less effective than models in conveying mechanistic reasoning. This study contributes evidence that articulating the genetic origin of variation is particularly challenging for learners and may require multiple cycles of instruction, assessment, and feedback. To support meaningful learning of the origin of variation, we advocate instruction that explicitly integrates multiple scales of biological organization, assessment that promotes and reveals mechanistic and causal reasoning, and practice with explanatory models with formative feedback. © 2014 E. Bray Speth et al. CBE—Life Sciences Education © 2014 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  18. Proposed reliability cost model

    Science.gov (United States)

    Delionback, L. M.

    1973-01-01

    The research investigations which were involved in the study include: cost analysis/allocation, reliability and product assurance, forecasting methodology, systems analysis, and model-building. This is a classic example of an interdisciplinary problem, since the model-building requirements include the need for understanding and communication between technical disciplines on one hand, and the financial/accounting skill categories on the other. The systems approach is utilized within this context to establish a clearer and more objective relationship between reliability assurance and the subcategories (or subelements) that provide, or reenforce, the reliability assurance for a system. Subcategories are further subdivided as illustrated by a tree diagram. The reliability assurance elements can be seen to be potential alternative strategies, or approaches, depending on the specific goals/objectives of the trade studies. The scope was limited to the establishment of a proposed reliability cost-model format. The model format/approach is dependent upon the use of a series of subsystem-oriented CER's and sometimes possible CTR's, in devising a suitable cost-effective policy.

  19. Rapid turns in European renewable energy policy: advocacy and framing of the proposed trading of guarantees of origin

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Maans; Nilsson, Lars J.; Ericsson, Karin

    2008-10-15

    The EU has assumed ambitious targets and strategies for the promotion of renewable sources of energy (RES) binding to all its member states. This report sets out to examine the proposed EU-wide policy instrument designed to help achieve the targets on renewable electricity and heat - the trading of Guarantees of Origin (GO). It analyses the fate of the GO trading proposal in the European policy-making machinery during 2007 and 2008. It first discusses its origins, key components and points of contention, and then examines key factors behind the policy development leading first to its development and subsequently to its abandonment in 2008. Addressing these factors, the report explores first the near-term policy-making process before and after the proposal on GO trading was tabled in January 2008, focusing on processes in the European bureaucracy and how they were influenced by different interest groups and member state governments. It then takes a step back and looks at how competing policy frames over time have shaped the GO instrument debate. Results show how a strong internal market frame acted as a primary driving force in the Commission throughout the 2000s to promote the GO trading instrument. The subsequent collapse of the GO trading proposal can be largely attributed to a) the lack of a strong lobby in favour of GO, b) the accumulated experience with and institutionalisation of national RES support policy, and c) growing general political concerns for supply security, innovation and competitiveness. In the end, the fall of the GO trading instrument is indicative of how the underlying political battle line between advocates of the European internal market and guardians of national interests has moved in favour of the latter in recent years. (author). refs

  20. NACP Regional: Original Observation Data and Biosphere and Inverse Model Outputs

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the originally-submitted observation measurement data, terrestrial biosphere model output data, and inverse model simulations that various...

  1. NACP Regional: Original Observation Data and Biosphere and Inverse Model Outputs

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains the originally-submitted observation measurement data, terrestrial biosphere model output data, and inverse model simulations that...

  2. The origin of risk aversion.

    Science.gov (United States)

    Zhang, Ruixun; Brennan, Thomas J; Lo, Andrew W

    2014-12-16

    Risk aversion is one of the most basic assumptions of economic behavior, but few studies have addressed the question of where risk preferences come from and why they differ from one individual to the next. Here, we propose an evolutionary explanation for the origin of risk aversion. In the context of a simple binary-choice model, we show that risk aversion emerges by natural selection if reproductive risk is systematic (i.e., correlated across individuals in a given generation). In contrast, risk neutrality emerges if reproductive risk is idiosyncratic (i.e., uncorrelated across each given generation). More generally, our framework implies that the degree of risk aversion is determined by the stochastic nature of reproductive rates, and we show that different statistical properties lead to different utility functions. The simplicity and generality of our model suggest that these implications are primitive and cut across species, physiology, and genetic origins.

  3. Origin of methyl torsional potential barrier – An overview

    Indian Academy of Sciences (India)

    Unknown

    The effect of skeletal flexing on the picture of barrier .... views to explain the origin of the barrier to this rotation have been proposed, but none of .... molecule, a model is always advantageous to predict the barrier and its cause in a given.

  4. Cognitive processes and neural basis of language switching: proposal of a new model.

    Science.gov (United States)

    Moritz-Gasser, Sylvie; Duffau, Hugues

    2009-12-09

    Although studies on bilingualism are abundant, cognitive processes and neural foundations of language switching received less attention. The aim of our study is to provide new insights to this still open question: do dedicated region(s) for language switching exist or is this function underlain by a distributed circuit of interconnected brain areas, part of a more general cognitive system? On the basis of recent behavioral, neuroimaging, and brain stimulation studies, we propose an original 'hodological' model of language switching. This process might be subserved by a large-scale cortico-subcortical network, with an executive system (prefrontal cortex, anterior cingulum, caudate nucleus) controlling a more dedicated language subcircuit, which involves postero-temporal areas, supramarginal and angular gyri, Broca's area, and the superior longitudinal fasciculus.

  5. Computed Tomography Image Origin Identification Based on Original Sensor Pattern Noise and 3-D Image Reconstruction Algorithm Footprints.

    Science.gov (United States)

    Duan, Yuping; Bouslimi, Dalel; Yang, Guanyu; Shu, Huazhong; Coatrieux, Gouenou

    2017-07-01

    In this paper, we focus on the "blind" identification of the computed tomography (CT) scanner that has produced a CT image. To do so, we propose a set of noise features derived from the image chain acquisition and which can be used as CT-scanner footprint. Basically, we propose two approaches. The first one aims at identifying a CT scanner based on an original sensor pattern noise (OSPN) that is intrinsic to the X-ray detectors. The second one identifies an acquisition system based on the way this noise is modified by its three-dimensional (3-D) image reconstruction algorithm. As these reconstruction algorithms are manufacturer dependent and kept secret, our features are used as input to train a support vector machine (SVM) based classifier to discriminate acquisition systems. Experiments conducted on images issued from 15 different CT-scanner models of 4 distinct manufacturers demonstrate that our system identifies the origin of one CT image with a detection rate of at least 94% and that it achieves better performance than sensor pattern noise (SPN) based strategy proposed for general public camera devices.

  6. Luminal Cells Are Favored as the Cell of Origin for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Zhu A. Wang

    2014-09-01

    Full Text Available The identification of cell types of origin for cancer has important implications for tumor stratification and personalized treatment. For prostate cancer, the cell of origin has been intensively studied, but it has remained unclear whether basal or luminal epithelial cells, or both, represent cells of origin under physiological conditions in vivo. Here, we use a novel lineage-tracing strategy to assess the cell of origin in a diverse range of mouse models, including Nkx3.1+/−; Pten+/−, Pten+/−, Hi-Myc, and TRAMP mice, as well as a hormonal carcinogenesis model. Our results show that luminal cells are consistently the observed cell of origin for each model in situ; however, explanted basal cells from these mice can generate tumors in grafts. Consequently, we propose that luminal cells are favored as cells of origin in many contexts, whereas basal cells only give rise to tumors after differentiation into luminal cells.

  7. The origin of mimicry : deception or merely coincidence?

    NARCIS (Netherlands)

    Wiggers, Bram; de Weerd, Harmen

    2017-01-01

    One of the most remarkable phenomena in nature is mimicry, in which one species (the mimic) evolves to imitate the phenotype of another species (the model). Several reasons for the origin of mimicry have been proposed, but no definitive conclusion has been found yet. In this paper, we test several

  8. A microhomology-mediated break-induced replication model for the origin of human copy number variation.

    Directory of Open Access Journals (Sweden)

    P J Hastings

    2009-01-01

    Full Text Available Chromosome structural changes with nonrecurrent endpoints associated with genomic disorders offer windows into the mechanism of origin of copy number variation (CNV. A recent report of nonrecurrent duplications associated with Pelizaeus-Merzbacher disease identified three distinctive characteristics. First, the majority of events can be seen to be complex, showing discontinuous duplications mixed with deletions, inverted duplications, and triplications. Second, junctions at endpoints show microhomology of 2-5 base pairs (bp. Third, endpoints occur near pre-existing low copy repeats (LCRs. Using these observations and evidence from DNA repair in other organisms, we derive a model of microhomology-mediated break-induced replication (MMBIR for the origin of CNV and, ultimately, of LCRs. We propose that breakage of replication forks in stressed cells that are deficient in homologous recombination induces an aberrant repair process with features of break-induced replication (BIR. Under these circumstances, single-strand 3' tails from broken replication forks will anneal with microhomology on any single-stranded DNA nearby, priming low-processivity polymerization with multiple template switches generating complex rearrangements, and eventual re-establishment of processive replication.

  9. A proposed best practice model validation framework for banks

    Directory of Open Access Journals (Sweden)

    Pieter J. (Riaan de Jongh

    2017-06-01

    Full Text Available Background: With the increasing use of complex quantitative models in applications throughout the financial world, model risk has become a major concern. The credit crisis of 2008–2009 provoked added concern about the use of models in finance. Measuring and managing model risk has subsequently come under scrutiny from regulators, supervisors, banks and other financial institutions. Regulatory guidance indicates that meticulous monitoring of all phases of model development and implementation is required to mitigate this risk. Considerable resources must be mobilised for this purpose. The exercise must embrace model development, assembly, implementation, validation and effective governance. Setting: Model validation practices are generally patchy, disparate and sometimes contradictory, and although the Basel Accord and some regulatory authorities have attempted to establish guiding principles, no definite set of global standards exists. Aim: Assessing the available literature for the best validation practices. Methods: This comprehensive literature study provided a background to the complexities of effective model management and focussed on model validation as a component of model risk management. Results: We propose a coherent ‘best practice’ framework for model validation. Scorecard tools are also presented to evaluate if the proposed best practice model validation framework has been adequately assembled and implemented. Conclusion: The proposed best practice model validation framework is designed to assist firms in the construction of an effective, robust and fully compliant model validation programme and comprises three principal elements: model validation governance, policy and process.

  10. On the origin of comets

    Science.gov (United States)

    Mendis, A.; Alfven, H.

    1976-01-01

    Physico-chemical processes leading to the dynamic formation and physical evolution of comets are reviewed in relationship to the various theories that propose solar origins, protoplanetary origins, planetary origins and interstellar origins. Evidence points to the origins of comets by the growth and agglomeration of small particles from gas and dust at very low temperatures at undetermined regions in space.

  11. Proposing a Metaliteracy Model to Redefine Information Literacy

    Science.gov (United States)

    Jacobson, Trudi E.; Mackey, Thomas P.

    2013-01-01

    Metaliteracy is envisioned as a comprehensive model for information literacy to advance critical thinking and reflection in social media, open learning settings, and online communities. At this critical time in higher education, an expansion of the original definition of information literacy is required to include the interactive production and…

  12. The origin of the medial circumflex femoral artery: a meta-analysis and proposal of a new classification system

    Directory of Open Access Journals (Sweden)

    Krzysztof A. Tomaszewski

    2016-02-01

    Full Text Available Background and Objectives. The medial circumflex femoral artery (MCFA is a common branch of the deep femoral artery (DFA responsible for supplying the femoral head and the greater trochanteric fossa. The prevalence rates of MCFA origin, its branching patterns and its distance to the mid-inguinal point (MIP vary significantly throughout the literature. The aim of this study was to determine the true prevalence of these characteristics and to study their associated anatomical and clinical relevance. Methods. A search of the major electronic databases Pubmed, EMBASE, Scopus, ScienceDirect, Web of Science, SciELO, BIOSIS, and CNKI was performed to identify all articles reporting data on the origin of the MCFA, its branching patterns and its distance to the MIP. No data or language restriction was set. Additionally, an extensive search of the references of all relevant articles was performed. All data on origin, branching and distance to MIP was extracted and pooled into a meta-analysis using MetaXL v2.0. Results. A total of 38 (36 cadaveric and 2 imaging studies (n = 4,351 lower limbs were included into the meta-analysis. The pooled prevalence of the MCFA originating from the DFA was 64.6% (95% CI [58.0–71.5], while the pooled prevalence of the MCFA originating from the CFA was 32.2% (95% CI [25.9–39.1]. The CFA-derived MCFA was found to originate as a single branch in 81.1% (95% CI [70.1–91.7] of cases with a mean pooled distance of 50.14 mm (95% CI [42.50–57.78] from the MIP. Conclusion. The MCFA’s variability must be taken into account by surgeons, especially during orthopedic interventions in the region of the hip to prevent iatrogenic injury to the circulation of the femoral head. Based on our analysis, we present a new proposed classification system for origin of the MCFA.

  13. The origin of the medial circumflex femoral artery: a meta-analysis and proposal of a new classification system.

    Science.gov (United States)

    Tomaszewski, Krzysztof A; Henry, Brandon M; Vikse, Jens; Roy, Joyeeta; Pękala, Przemysław A; Svensen, Maren; Guay, Daniel L; Saganiak, Karolina; Walocha, Jerzy A

    2016-01-01

    Background and Objectives. The medial circumflex femoral artery (MCFA) is a common branch of the deep femoral artery (DFA) responsible for supplying the femoral head and the greater trochanteric fossa. The prevalence rates of MCFA origin, its branching patterns and its distance to the mid-inguinal point (MIP) vary significantly throughout the literature. The aim of this study was to determine the true prevalence of these characteristics and to study their associated anatomical and clinical relevance. Methods. A search of the major electronic databases Pubmed, EMBASE, Scopus, ScienceDirect, Web of Science, SciELO, BIOSIS, and CNKI was performed to identify all articles reporting data on the origin of the MCFA, its branching patterns and its distance to the MIP. No data or language restriction was set. Additionally, an extensive search of the references of all relevant articles was performed. All data on origin, branching and distance to MIP was extracted and pooled into a meta-analysis using MetaXL v2.0. Results. A total of 38 (36 cadaveric and 2 imaging) studies (n = 4,351 lower limbs) were included into the meta-analysis. The pooled prevalence of the MCFA originating from the DFA was 64.6% (95% CI [58.0-71.5]), while the pooled prevalence of the MCFA originating from the CFA was 32.2% (95% CI [25.9-39.1]). The CFA-derived MCFA was found to originate as a single branch in 81.1% (95% CI [70.1-91.7]) of cases with a mean pooled distance of 50.14 mm (95% CI [42.50-57.78]) from the MIP. Conclusion. The MCFA's variability must be taken into account by surgeons, especially during orthopedic interventions in the region of the hip to prevent iatrogenic injury to the circulation of the femoral head. Based on our analysis, we present a new proposed classification system for origin of the MCFA.

  14. A proposed general model of information behaviour.

    Directory of Open Access Journals (Sweden)

    2003-01-01

    Full Text Available Presents a critical description of Wilson's (1996 global model of information behaviour and proposes major modification on the basis of research into information behaviour of managers, conducted in Poland. The theoretical analysis and research results suggest that Wilson's model has certain imperfections, both in its conceptual content, and in graphical presentation. The model, for example, cannot be used to describe managers' information behaviour, since managers basically are not the end users of external from organization or computerized information services, and they acquire information mainly through various intermediaries. Therefore, the model cannot be considered as a general model, applicable to every category of information users. The proposed new model encompasses the main concepts of Wilson's model, such as: person-in-context, three categories of intervening variables (individual, social and environmental, activating mechanisms, cyclic character of information behaviours, and the adoption of a multidisciplinary approach to explain them. However, the new model introduces several changes. They include: 1. identification of 'context' with the intervening variables; 2. immersion of the chain of information behaviour in the 'context', to indicate that the context variables influence behaviour at all stages of the process (identification of needs, looking for information, processing and using it; 3. stress is put on the fact that the activating mechanisms also can occur at all stages of the information acquisition process; 4. introduction of two basic strategies of looking for information: personally and/or using various intermediaries.

  15. Travelling in Time and Space at the Origins of Language

    Directory of Open Access Journals (Sweden)

    Francesco Ferretti

    2014-12-01

    Full Text Available In this paper we propose a narrative hypothesis on the nature of language and a proto-discursive hypothesis on the origin of our communicative abilities. Our proposal is based on two assumptions. The first assumption, concerning the properties of language, is tied to the idea that global discourse coherence governs the origin of our communicative abilities as well the functioning of these abilities. The second assumption, concerning processing devices, is connected to the idea that the systems of spatial and temporal navigation are implicated in discourse coherence processing. Analysis of the relationship between these two assumptions allows us to integrate the model of language based on clues proposed by Sperber and Wilson with Relevance Theory with the discursive foundation of human communication. In this respect, our proposal can be considered as a tentative extension of Relevance Theory (both at the level of properties and the level of cognitive systems.

  16. Sur l’origine de l’écriture libyque. Quelques propositions On the origin of the Libyco-Berber alphabet: A few proposals

    Directory of Open Access Journals (Sweden)

    Dominique Casajus

    2013-06-01

    Full Text Available Le présent article propose quelques hypothèses sur l’origine des alphabets dits libyques. Attestés par plus d’un millier d’inscriptions recueillies dans toute l’Afrique du Nord, depuis la Libye jusqu’aux îles Canaries, ces alphabets sont selon toute vraisemblance les ancêtres des alphabets touaregs actuels. La seule inscription qui ait pu être datée avec un degré raisonnable de certitude est une bilingue libyco-punique, mise au jour sur le site de Dougga (Tunisie, qui daterait de 139 avant J.-C. Il semble que les alphabets libyques existaient déjà alors depuis plusieurs siècles. Leurs créateurs ont emprunté quelques lettres (au moins quatre aux alphabets phénico-puniques. Pour composer les autres lettres, ils semblent avoir eu recours à des procédés géométriques simples qu’on essaie ici de reconstituer.A few hypotheses about the origin of the so-called “Libyan” alphabets are presented. Attested in more than a thousand inscriptions from Libya to the Canary Islands in northern Africa, these alphabets are probably the forebears of the current ones used by the Tuareg. The only inscription that has been dated (139 BCE with a reasonable degree of certainty is bilingual, Libyco-Punic, from Dougga in Tunisia. The “Libyan” alphabets apparently already existed, several centuries earlier. Their creators borrowed a few — at least four — letters from the Phoenician/Punic alphabets; and apparently used simple geometric procedures, which are reconstituted herein, for the other letters.

  17. On the structure and origin of HH jets.

    Science.gov (United States)

    De Colle, Fabio

    2011-10-01

    The goal of this proposal is to study the structure and origin of jets from young stellar objects by using HST observations of T Tauri jets. To this end, we propose to use three different but complementary approaches: tomographic reconstruction to recover the jet velocity cross-section, numerical simulations to compare the predictions of jet ejection models with the observations, and a statistical analysis of the data. First, we plan to use standard tomographic reconstruction techniques to derive the cross-section {i.e. perpendicular to the jet axis} velocity and physical parameters {electron density, temperature and ionization fraction} of the jets. This will allow a reliable estimation of mass- and momentum-flux from the central star-disk system, which, together with the cross-sectional velocity constraints, will help to distinguish between different jet ejection models. Second, we will focus our study on understanding recent observations of stellar jets showing transverse velocity shifts in several emission lines. The origin of these velocity shift is still debated: they can be interpreted as evidence of rotation, or they can be originated by side-to-side asymmetries in the flow or in the ambient medium. To distinguish between these two scenarios, we plan to uncover the origin of transverse velocity shift by a statistical approach based on the presence {or absence} of correlations between the velocity shifts and the degree of asymmetries in the flow. Finally, we will use our adaptive mesh refinement code to compare the observations with a large number of numerical simulations constructed on different jet ejection mechanisms.

  18. A proposed wind shift model for the German reactor safety study

    International Nuclear Information System (INIS)

    Aldrich, D.C.; Bayer, A.; Schueckler, M.

    1979-04-01

    To account for hourly wind direction changes, a wind shift model has been proposed. Using hourly recorded wind speed and direction data, the model modifies the angular distribution of radionuclide concentrations calculated by a straightline model, and is intended to better represent the concentrations in areas close to the reactor where potential doses might exceed the threshold level for early fatalities. 115 weather sequences were used, both with and without the proposed wind shift model, to calculate probability distributions for early fatalities. The use of the proposed model results in a reduction of the mean and peak values of that distribution by 36% and 29%, respectively. (orig./HP) [de

  19. Jigsaw model of the origin of life

    Science.gov (United States)

    McGowan, John F.

    2002-02-01

    It is suggested that life originated in a three-step process referred to as the jigsaw model. RNA, proteins, or similar organic molecules polymerized in a dehydrated carbon-rich environment, on surfaces in a carbon-rich environment, or in another environment where polymerization occurs. These polymers subsequently entered an aqueous environment where they folded into compact structures. It is argued that the folding of randomly generated polymers such as RNA or proteins in water tends to partition the folded polymer into domains with hydrophobic cores and matching shapes to minimize energy. In the aqueous environment hydrolysis or other reactions fragmented the compact structures into two or more matching molecules, occasionally producing simple living systems, also knows as autocatalytic sets of molecules. It is argued that the hydrolysis of folded polymers such as RNA or proteins is not random. The hydrophobic cores of the domains are rarely bisected due to the energy requirements in water. Hydrolysis preferentially fragments the folded polymers into pieces with complementary structures and chemical affinities. Thus the probability of producing a system of matched, interacting molecules in prebiotic chemistry is much higher than usually estimated. Environments where this process may occur are identified. For example, the jigsaw model suggests life may have originated at a seep or carbonaceous fluids beneath the ocean. The polymerization occurred beneath the sea floor. The folding and fragmentation occurred in the ocean. The implications of this hypothesis for seeking life or prebiotic chemistry in the Solar System are explored.

  20. Illuminating the origins of spectral properties of green fluorescent proteins via proteochemometric and molecular modeling.

    Science.gov (United States)

    Nantasenamat, Chanin; Simeon, Saw; Owasirikul, Wiwat; Songtawee, Napat; Lapins, Maris; Prachayasittikul, Virapong; Wikberg, Jarl E S

    2014-10-15

    Green fluorescent protein (GFP) has immense utility in biomedical imaging owing to its autofluorescent nature. In efforts to broaden the spectral diversity of GFP, there have been several reports of engineered mutants via rational design and random mutagenesis. Understanding the origins of spectral properties of GFP could be achieved by means of investigating its structure-activity relationship. The first quantitative structure-property relationship study for modeling the spectral properties, particularly the excitation and emission maximas, of GFP was previously proposed by us some years ago in which quantum chemical descriptors were used for model development. However, such simplified model does not consider possible effects that neighboring amino acids have on the conjugated π-system of GFP chromophore. This study describes the development of a unified proteochemometric model in which the GFP chromophore and amino acids in its vicinity are both considered in the same model. The predictive performance of the model was verified by internal and external validation as well as Y-scrambling. Our strategy provides a general solution for elucidating the contribution that specific ligand and protein descriptors have on the investigated spectral property, which may be useful in engineering novel GFP variants with desired characteristics. Copyright © 2014 Wiley Periodicals, Inc.

  1. Gamification in online education: proposal for a participatory learning model

    Directory of Open Access Journals (Sweden)

    Fabiana Bigão Silva

    2017-09-01

    Full Text Available Empirical studies have suggested limitations on the form of application of gamification mechanics in the context of online education. These mechanics have been applied without reference to a theoretical model dedicated to this type of education. The objective of the paper is to propose a model for a gamified platform for online education that contributes to a more participatory learning, taking into account the different student profiles. Based on literature review about approaches to gamification systems design, a set of steps was followed in order to develop a generic model for a framework dedicated to online education. The model proposed is based on the Educational Gamification Design Principles proposed by Dicheva et al. (2015. The model may contribute to the promotion of participatory learning, taking into account the different student profiles. The results of such evaluation will be published in the future.

  2. A model for the stochastic origins of Schrodinger's equation

    OpenAIRE

    Davidson, Mark P.

    2001-01-01

    A model for the motion of a charged particle in the vacuum is presented which, although purely classical in concept, yields Schrodinger's equation as a solution. It suggests that the origins of the peculiar and nonclassical features of quantum mechanics are actually inherent in a statistical description of the radiative reactive force.

  3. A proposed residual stress model for oblique turning

    International Nuclear Information System (INIS)

    Elkhabeery, M. M.

    2001-01-01

    A proposed mathematical model is presented for predicting the residual stresses caused by turning. Effects of change in tool free length, cutting speed, feed rate, and the tensile strength of work piece material on the maximum residual stress are investigated. The residual stress distribution in the surface region due to turning under unlubricated condition is determined using a deflection etching technique. To reduce the number of experiments required and build the mathematical model for these variables, Response Surface Methodology (RSM) is used. In addition, variance analysis and an experimental check are conducted to determine the prominent parameters and the adequacy of the model. The results show that the tensile stress of the work piece material, cutting speed, and feed rate have significant effects on the maximum residual stresses. The proposed model, that offering good correlation between the experimental and predicted results, is useful in selecting suitable cutting parameters for the machining of different materials. (author)

  4. A proposed experiment on ball lightning model

    International Nuclear Information System (INIS)

    Ignatovich, Vladimir K.; Ignatovich, Filipp V.

    2011-01-01

    Highlights: → We propose to put a glass sphere inside an excited gas. → Then to put a light ray inside the glass in a whispering gallery mode. → If the light is resonant to gas excitation, it will be amplified at every reflection. → In ms time the light in the glass will be amplified, and will melt the glass. → A liquid shell kept integer by electrostriction forces is the ball lightning model. -- Abstract: We propose an experiment for strong light amplification at multiple total reflections from active gaseous media.

  5. Brief communication: human cranial variation fits iterative founder effect model with African origin.

    Science.gov (United States)

    von Cramon-Taubadel, Noreen; Lycett, Stephen J

    2008-05-01

    Recent studies comparing craniometric and neutral genetic affinity matrices have concluded that, on average, human cranial variation fits a model of neutral expectation. While human craniometric and genetic data fit a model of isolation by geographic distance, it is not yet clear whether this is due to geographically mediated gene flow or human dispersal events. Recently, human genetic data have been shown to fit an iterative founder effect model of dispersal with an African origin, in line with the out-of-Africa replacement model for modern human origins, and Manica et al. (Nature 448 (2007) 346-349) have demonstrated that human craniometric data also fit this model. However, in contrast with the neutral model of cranial evolution suggested by previous studies, Manica et al. (2007) made the a priori assumption that cranial form has been subject to climatically driven natural selection and therefore correct for climate prior to conducting their analyses. Here we employ a modified theoretical and methodological approach to test whether human cranial variability fits the iterative founder effect model. In contrast with Manica et al. (2007) we employ size-adjusted craniometric variables, since climatic factors such as temperature have been shown to correlate with aspects of cranial size. Despite these differences, we obtain similar results to those of Manica et al. (2007), with up to 26% of global within-population craniometric variation being explained by geographic distance from sub-Saharan Africa. Comparative analyses using non-African origins do not yield significant results. The implications of these results are discussed in the light of the modern human origins debate. (c) 2007 Wiley-Liss, Inc.

  6. Musical emotions: Functions, origins, evolution

    Science.gov (United States)

    Perlovsky, Leonid

    2010-03-01

    Theories of music origins and the role of musical emotions in the mind are reviewed. Most existing theories contradict each other, and cannot explain mechanisms or roles of musical emotions in workings of the mind, nor evolutionary reasons for music origins. Music seems to be an enigma. Nevertheless, a synthesis of cognitive science and mathematical models of the mind has been proposed describing a fundamental role of music in the functioning and evolution of the mind, consciousness, and cultures. The review considers ancient theories of music as well as contemporary theories advanced by leading authors in this field. It addresses one hypothesis that promises to unify the field and proposes a theory of musical origin based on a fundamental role of music in cognition and evolution of consciousness and culture. We consider a split in the vocalizations of proto-humans into two types: one less emotional and more concretely-semantic, evolving into language, and the other preserving emotional connections along with semantic ambiguity, evolving into music. The proposed hypothesis departs from other theories in considering specific mechanisms of the mind-brain, which required the evolution of music parallel with the evolution of cultures and languages. Arguments are reviewed that the evolution of language toward becoming the semantically powerful tool of today required emancipation from emotional encumbrances. The opposite, no less powerful mechanisms required a compensatory evolution of music toward more differentiated and refined emotionality. The need for refined music in the process of cultural evolution is grounded in fundamental mechanisms of the mind. This is why today's human mind and cultures cannot exist without today's music. The reviewed hypothesis gives a basis for future analysis of why different evolutionary paths of languages were paralleled by different evolutionary paths of music. Approaches toward experimental verification of this hypothesis in

  7. <Original Paper>Interaction Model of Mental Disability (IMMD) based on ICIDH

    OpenAIRE

    YAMANE, Hiroshi

    2001-01-01

    I propose an "Interaction Model of Mental Disability (IMMD)". Several models based on ICIDH are being proposed and tested around the world focusing on different aspects of disability. Though ICIDH is an inclusive model in health services, social security, insurance, education, and so on, the remarkable point of IMMD is to visualize the mutual relation of mental disability (impairment, disability and handicap) and other factors (environmental factors, personal factors). IMMD is a practical reh...

  8. A Proposed Conceptual Model of Military Medical Readiness

    National Research Council Canada - National Science Library

    Van Hall, Brian M

    2007-01-01

    .... The purpose of this research is to consolidate existing literature on the latent variable of medical readiness, and to propose a composite theoretical model of medical readiness that may provide...

  9. Modeling Instruction of David Hestenes: a proposal of thematic modeling cycle and discussion of scientific literacy

    Directory of Open Access Journals (Sweden)

    Ednilson Sergio Ramalho de Souza

    2016-07-01

    Full Text Available The pedagogical work with mathematical modeling assumes investigate situations of reality. However, mental models formed from the contact with the experiential world are generally incompatible with the conceptual models. So David Hestenes supports the view that one of the biggest challenges of teaching and learning in science and mathematics is to coordinate conceptual models with mental models, which led to the elaboration of a didactic in mathematical modeling: Modeling Instruction. Our goal is to present a proposal for thematic modeling cycle drawn up in hestenesianos assumptions and discuss possibilities for scientific literacy. The main question was to know how to emerge indicators for scientific literacy for the proposed cycle. This is a bibliographic research in order to identify the available literature contributions on the subject and raise the possibility and challenges for the brazilian teaching science and mathematics. Preliminary results indicate that the proposed modeling cycle can develop indicators for scientific literacy of different natures.

  10. A New Proposed Cost Model for List Accessing Problem using Buffering

    OpenAIRE

    Mohanty, Rakesh; Bhoi, Seetaya; Tripathy, Sasmita

    2011-01-01

    There are many existing well known cost models for the list accessing problem. The standard cost model developed by Sleator and Tarjan is most widely used. In this paper, we have made a comprehensive study of the existing cost models and proposed a new cost model for the list accessing problem. In our proposed cost model, for calculating the processing cost of request sequence using a singly linked list, we consider the access cost, matching cost and replacement cost. The cost of processing a...

  11. The Origin and Evolution of the Behavior Analysis Program at the University of Nevada, Reno.

    Science.gov (United States)

    Hayes, Linda J; Houmanfar, Ramona A; Ghezzi, Patrick M; Williams, W Larry; Locey, Matthew; Hayes, Steven C

    2016-05-01

    The origins of the Behavior Analysis program at the University of Nevada, Reno by way of a self-capitalized model through its transition to a more typical graduate program is described. Details of the original proposal to establish the program and the funding model are described. Some of the unusual features of the program executed in this way are discussed, along with problems engendered by the model. Also included is the diversification of faculty interests over time. The status of the program, now, after 25 years of operation, is presented.

  12. A Proposed Systems Model for Socializing the Graduate Writer

    Science.gov (United States)

    Jones, David R.

    2018-01-01

    Although researchers chorus the need to support graduate students toward higher levels of writing proficiency, their findings lack a holistic model for doing so. A model emerges upon scrutiny of the factors that have been implicated in supporting writing proficiency. In the proposed model, a socialization theory fits as a proximal process into the…

  13. Revisiting the theoretical basis of the endosymbiotic origin of plastids in the original context of Lynn Margulis on the origin of mitosing, eukaryotic cells.

    Science.gov (United States)

    Sato, Naoki

    2017-12-07

    Fifty years ago, Lynn Margulis proposed a comprehensive hypothesis on the origin of eukaryotic cells with an emphasis on the origin of mitosis. This hypothesis postulated that the eukaryotic cell is a composite of different parts as a result of the symbiosis of various different bacteria. In this hypothesis, she integrated previously proposed ideas that mitochondria and chloroplasts were descendants of endosymbionts that originated from aerobic bacteria and blue-green algae (now cyanobacteria), respectively. However, the major part of her hypothesis, which she believed to be original, was the origin of mitosis. The core of her postulate involved a chromosome partition mechanism dependent on DNA-microtubule binding, which originated from a hypothetical centriole-DNA complex, with an ability to replicate. Surprisingly, her complete lack of real experimental works in the cytoskeleton, cell motility, or paleontology did not prevent this 29-year-old junior scientist from assembling archival knowledge and constructing a narrative on the evolution of all organisms. Whether the centriole-DNA complex originated from a spirochete or not was a minor anecdote in this initial postulate. Unfortunately, this hypothesis on the origin of mitosis, which she believed to be a holistic unity, testable by experiments, was entirely refuted. Despite falsification of her original narrative as a whole, her success as a founder of endosymbiotic theory on the origin of mitochondria and chloroplasts is undoubted. We will discuss the reasons for her success in terms of the historical situation in the latter half of the 20th century. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Modelling the fathering role: Experience in the family of origin and father involvement

    Directory of Open Access Journals (Sweden)

    Mihić Ivana

    2012-01-01

    Full Text Available The study presented in this paper deals with the effects of experiences with father in the family of origin on the fathering role in the family of procreation. The results of the studies so far point to great importance of such experiences in parental role modelling, while recent approaches have suggested the concept of introjected notion or an internal working model of the fathering role as the way to operationalise the transgenerational transfer. The study included 247 two-parent couple families whose oldest child attended preschool education. Fathers provided information on self-assessed involvement via the Inventory of father involvement, while both fathers and mothers gave information on introjected experiences from the family of origin via the inventory Presence of the father in the family of origin. It was shown that father’s experiences from the family of origin had significant direct effects on his involvement in child-care. Very important experiences were those of negative emotional exchange, physical closeness and availability of the father, as well as beliefs about the importance of the father as a parent. Although maternal experiences from the family of origin did not contribute significantly to father involvement, shared beliefs about father’s importance as a parent in the parenting alliance had an effect on greater involvement in child-care. The data provide confirmation of the hypotheses on modelling of the fathering role, but also open the issue of the factor of intergenerational maintenance of traditional forms of father involvement in families in Serbia.

  15. A proposal about the origin of the indo-european locative plural

    Directory of Open Access Journals (Sweden)

    Kenneth Shields

    2005-12-01

    Full Text Available One of the most significant recent developments in the field of historical lin­ guistics has been the identification of what Fox (1995: 194 calls '"laws' oflanguage development"-a methodology "for determining which changes are more likely than others, and ... criteria for determining the overall direction of linguistic change." This methodology is largely an aspect of what has come to be known as "grammati­ calization theory," which, according to Heine (2003: 575, is really "neither a theory of language nor of language change; its goal is to describe grammaticalization, that is, the way grammatical forms arise and develop through space and time, and to explain why they are structured the way they are." The process of grammaticalization "is hypothesized to be essentially unidirectional" (Heine 2003: 575 and therefore potentially "offers an explanatory account of how and why grammatical categories arise and develop" (Heine 2003: 578. Such explanation serves as "a potentially powerful adjunct to the methods of reconstruction, especially on an internal basis" (Fox 1995: 206, since it leads the historical linguist to principled conclusions about the structural sources of both attested and comparatively reconstructed morpho­ syntactic patterns. In this brief paper I wish to apply one such '"law' of language development" to account for the origin of the traditionally reconstructed Inda-European locative plural suffixes *-si (Gk. -si and *-su (Skt. -su, OCS -Xb (cf. Szemerényi 1996: 165. Like Fox (1995: 206, I acknowledge that the application of this methodology can be "speculative and controversial"; however, I offer my proposal as a reasonable possibility for developments within Indo-European

  16. The Role of Stochastic Models in Interpreting the Origins of Biological Chirality

    Directory of Open Access Journals (Sweden)

    Gábor Lente

    2010-04-01

    Full Text Available This review summarizes recent stochastic modeling efforts in the theoretical research aimed at interpreting the origins of biological chirality. Stochastic kinetic models, especially those based on the continuous time discrete state approach, have great potential in modeling absolute asymmetric reactions, experimental examples of which have been reported in the past decade. An overview of the relevant mathematical background is given and several examples are presented to show how the significant numerical problems characteristic of the use of stochastic models can be overcome by non-trivial, but elementary algebra. In these stochastic models, a particulate view of matter is used rather than the concentration-based view of traditional chemical kinetics using continuous functions to describe the properties system. This has the advantage of giving adequate description of single-molecule events, which were probably important in the origin of biological chirality. The presented models can interpret and predict the random distribution of enantiomeric excess among repetitive experiments, which is the most striking feature of absolute asymmetric reactions. It is argued that the use of the stochastic kinetic approach should be much more widespread in the relevant literature.

  17. Main features of the proposed NCRP respiratory tract model

    International Nuclear Information System (INIS)

    Phalen, R.F.; Fisher, G.L.; Moss, O.R.; Schlesinger, R.B.; Swift, D.L.

    1991-01-01

    The proposed NCRP respiratory tract dosimetry model regions include the naso-oro-pharyngo-laryngeal (NOPL), the tracheobronchial (TB), the pulmonary (P), and the lymph nodes (LN). Input aerosol concentrations are derived from a consideration of particle-size-dependent inspirability. Particle deposition in the respiratory tract is modelled using the mechanisms of inertial impaction, sedimentation and diffusion. The rates of absorption of particles, and transport to the blood, have been derived from clearance data from people and laboratory animals. The effect of body growth on particle deposition is considered. Particle clearance rates are assumed to be independent of age. The proposed respiratory tract model differs significantly from the 1966 Task Group Model in that (1) inspirability is considered; (2) new sub-regions of the respiratory tract are considered; (3) absorption of materials by the blood is treated in a more sophisticated fashion; and (4) body size (and thus age) is taken into account. (author)

  18. An Analytical Analysis of Hydraulic Jump in Triangular Channel: A Proposed Model

    Science.gov (United States)

    Khan, S. A.

    2013-05-01

    The paper presents the theoretical study of hydraulic jump in triangular channel section. Presuming the jump as one dimensional free shear layer with hydrostatic pressure distribution across it and using momentum equation, specific force equation is obtained. Using the specific force equation and eddy viscosity equation, analytical models for sequent depth, dimensionless profile, turbulent shear stress distribution and energy loss for various initial Froude numbers have been obtained. The proposed models for sequent depth and energy loss are also compared with the other developed models. The proposed energy loss model also provides the energy loss at any point along the jump, while this provision is not available in the models of other investigators. Newton-Raphson and Runge-Kutta methods are used for the solution of the proposed model. The outcome of this study can be used in the design of stilling basin floor and side walls on permeable foundations.

  19. Exploring the origin of broad-band emissions of Mrk 501 with a two-zone model

    Science.gov (United States)

    Lei, Maichang; Yang, Chuyuan; Wang, Jiancheng; Yang, Xiaolin

    2018-04-01

    We propose a two-zone synchrotron self-Compton (SSC) model, including an inner gamma-ray emitting region with spherical shape and a conical radio emitting region located at the extended jet, to alleviate the long-standing "bulk Lorentz factor crisis" in blazars. In this model, the spectral energy distributions (SEDs) of blazars are produced by considering the gamma-ray emitting region inverse Compton scattering of both the synchrotron photons itself and the ambient photons from the radio emitting region. Applying the model to Mrk 501, we obtain that the radio emitting region has a comoving length of ˜0.15 pc and is located at sub-parsec scale from the central engine by modeling the radio data; the flux of the Compton scattering of the ambient photons is so low that it can be neglected safely. The characteristic hard gamma-ray spectrum can be explained by the superposition of two SSC processes, and the model can approximately explain the very high energy (VHE) data. The insights into the spectral shape and the inter-band correlations under the flaring state will provide us with a diagnostic for the bulk Lorentz factor of radio emitting region, where the low and upper limits of 8 and 15 are preferred, and for the two-zone SSC model itself. In addition, our two-zone SSC model shows that the gamma-ray emitting region creates flare on the timescale of merely a few hours, and the long time outbursts more likely originate from the extended radio emitting region.

  20. Proposal of a new biokinetic model for niobium

    International Nuclear Information System (INIS)

    Oliveira, Roges

    2006-01-01

    There are two niobium isotopes generated in nuclear power plants: 95 Nb and 94 Nb. Workers and members of the public are subjects to intake these radionuclides in accident situation. For dose calculation purpose, it is very important to develop a model that describes in a more realistic way the kinetics of niobium inside of the human body. Presently the model adopted by ICRP (ICRP, 1989) is based on animal studies and describes the behavior of niobium in human being in a simple manner. The new model proposal describes the kinetics of the niobium from the intake into the blood until the excretion, doing this in a more realistic form and considering not only data from animals but data from human beings as well. For this objective, a workers group of a niobium extraction and processing industry exposed to stable niobium (93 Nb) in oxide insoluble form with associated uranium, was monitored for uranium and niobium determination in urinary and fecal excretion, by mass spectrometry. Based in the ratios of the niobium concentration in urinary and faecal excretion of this workers and animal data study, a new biokinetic model for niobium was proposed, with the followings modifications relative to ICRP model: a new compartment that represents muscular tissue; the fractions which are deposited into the compartment are modified; a third component in the retention equation of the bone tissue; introduction of recirculation between organs and blood. The new model was applied for a case of accidental intake and described adequately the experimental data

  1. A Modified Microfinance Model Proposed for the United States

    Directory of Open Access Journals (Sweden)

    Eldon H Bernstein

    2014-07-01

    While the goal in the traditional model in developing markets is the elimination of poverty, we show how those critical conditions help to explain the lack of success in the United States.  We propose a modified model whose goal is the creation of an entrepreneurial venture or improving the performance of an existing small enterprise.

  2. A common mode of origin of power laws in models of market and earthquake

    Science.gov (United States)

    Bhattacharyya, Pratip; Chatterjee, Arnab; Chakrabarti, Bikas K.

    2007-07-01

    We show that there is a common mode of origin for the power laws observed in two different models: (i) the Pareto law for the distribution of money among the agents with random-saving propensities in an ideal gas-like market model and (ii) the Gutenberg-Richter law for the distribution of overlaps in a fractal-overlap model for earthquakes. We find that the power laws appear as the asymptotic forms of ever-widening log-normal distributions for the agents’ money and the overlap magnitude, respectively. The identification of the generic origin of the power laws helps in better understanding and in developing generalized views of phenomena in such diverse areas as economics and geophysics.

  3. Cell of Origin and Cancer Stem Cells in Tumor Suppressor Mouse Models of Glioblastoma.

    Science.gov (United States)

    Alcantara Llaguno, Sheila R; Xie, Xuanhua; Parada, Luis F

    2016-01-01

    The cellular origins and the mechanisms of progression, maintenance of tumorigenicity, and therapeutic resistance are central questions in the glioblastoma multiforme (GBM) field. Using tumor suppressor mouse models, our group recently reported two independent populations of adult GBM-initiating central nervous system progenitors. We found different functional and molecular subtypes depending on the tumor-initiating cell lineage, indicating that the cell of origin is a driver of GBM subtype diversity. Using an in vivo model, we also showed that GBM cancer stem cells (CSCs) or glioma stem cells (GSCs) contribute to resistance to chemotherapeutic agents and that genetic ablation of GSCs leads to a delay in tumor progression. These studies are consistent with the cell of origin and CSCs as critical regulators of the pathogenesis of GBM. © 2016 Alcantara Llaguno et al; Published by Cold Spring Harbor Laboratory Press.

  4. Making sense of resilience: a review from the field of paediatric psycho-oncology and a proposal of a model for its study

    Directory of Open Access Journals (Sweden)

    Carmina Castellano-Tejedor

    2014-10-01

    Full Text Available This article is intended to review the concept of resilience from the scope of paediatric psycho-oncology. The origin, its different definitions and its suitability of application in the field of serious physical illness - such as cancer - will be analyzed. Furthermore, the differences between resilience and other concepts commonly associated or confused with it, such as post-traumatic growth or benefit finding, will be discussed. Finally, a proposal for a comprehensive model of resilience in paediatric cancer will be put forward.

  5. Libertarianism and Original Appropriation

    OpenAIRE

    Dominiak, Łukasz

    2017-01-01

    The article is devoted to the problem of the structure of libertarian theory of justice. It tries to present a map of the main concepts and principles of this theory and to investigate its possible justifications. It explains such fundamental concepts as original appropriation, homesteading, labour theory of property or first possession theory of original appropriation. The article shows merits and drawbacks of alternative libertarian principles of justice in first acquisition and proposes a ...

  6. Discriminating the Geographical Origins of Chinese White Lotus Seeds by Near-Infrared Spectroscopy and Chemometrics

    Directory of Open Access Journals (Sweden)

    Lu Xu

    2015-01-01

    Full Text Available The traceability of a Chinese white lotus seed (WLS with Protected Designation of Origin (PDO was investigated using near-infrared (NIR spectroscopy and chemometrics. Three chemometrics methods, discrimination analysis (DA, class modeling, and a newly proposed strategy, the fusion of DA and class modeling, were investigated to compare their capacity to trace the geographical origins of WLS. Least squares support vector machine (LS-SVM was developed to distinguish the PDO WLS from non-PDO WLS of four main producing areas. A class modeling technique, one-class partial least squares (OCPLS, was developed only using the data of PDO WLS. By the fusion of LS-SVM and OCPLS, the best prediction sensitivity and specificity were 0.900 and 0.973, respectively. The results indicate that fusion of DA and class modeling can enhance the specificity for detection of non-PDO products. The conclusion is that DA and class modeling should be combined for tracing food geographical origins.

  7. The origin of the third family festschrift Zichichi on the 30th anniversary of the proposal to search for the third lepton at ADONE

    CERN Document Server

    Wu Chien Shiung; Ricci, Renato Angelo; Maiani, Luciano; Barnabei, Ottavio; Wolf, Gunter; Wiik, Bjørn Haavard; Petermann, Andreas; Conversi, Marcello; Villi, C; Ting, Samuel C C; Weisskopf, Victor Frederick; Cabibbo, Nicola; Lee Tsung Dao

    1998-01-01

    In 1967 a group of physicists from the University of Bologna, led by A Zichichi, published a proposal to search for a heavy lepton using the Frascati (e + e - ) collider. The proposal, whose key pages are reproduced in this book on the 30th anniversary of the publication, was the consequence of many years of work started at CERN, where, in addition to the original idea of searching for a heavy lepton carrying its own leptonic number, new technologies were invented to allow the detection of a signal whose identification against the high background of hadronic processes was extremely difficult.M

  8. Interactive visual exploration and analysis of origin-destination data

    Science.gov (United States)

    Ding, Linfang; Meng, Liqiu; Yang, Jian; Krisp, Jukka M.

    2018-05-01

    In this paper, we propose a visual analytics approach for the exploration of spatiotemporal interaction patterns of massive origin-destination data. Firstly, we visually query the movement database for data at certain time windows. Secondly, we conduct interactive clustering to allow the users to select input variables/features (e.g., origins, destinations, distance, and duration) and to adjust clustering parameters (e.g. distance threshold). The agglomerative hierarchical clustering method is applied for the multivariate clustering of the origin-destination data. Thirdly, we design a parallel coordinates plot for visualizing the precomputed clusters and for further exploration of interesting clusters. Finally, we propose a gradient line rendering technique to show the spatial and directional distribution of origin-destination clusters on a map view. We implement the visual analytics approach in a web-based interactive environment and apply it to real-world floating car data from Shanghai. The experiment results show the origin/destination hotspots and their spatial interaction patterns. They also demonstrate the effectiveness of our proposed approach.

  9. Linear regression crash prediction models : issues and proposed solutions.

    Science.gov (United States)

    2010-05-01

    The paper develops a linear regression model approach that can be applied to : crash data to predict vehicle crashes. The proposed approach involves novice data aggregation : to satisfy linear regression assumptions; namely error structure normality ...

  10. A Proposed Model of Jazz Theory Knowledge Acquisition

    Science.gov (United States)

    Ciorba, Charles R.; Russell, Brian E.

    2014-01-01

    The purpose of this study was to test a hypothesized model that proposes a causal relationship between motivation and academic achievement on the acquisition of jazz theory knowledge. A reliability analysis of the latent variables ranged from 0.92 to 0.94. Confirmatory factor analyses of the motivation (standardized root mean square residual…

  11. A Systematic Identification Method for Thermodynamic Property Modelling

    DEFF Research Database (Denmark)

    Ana Perederic, Olivia; Cunico, Larissa; Sarup, Bent

    2017-01-01

    In this work, a systematic identification method for thermodynamic property modelling is proposed. The aim of the method is to improve the quality of phase equilibria prediction by group contribution based property prediction models. The method is applied to lipid systems where the Original UNIFAC...... model is used. Using the proposed method for estimating the interaction parameters using only VLE data, a better phase equilibria prediction for both VLE and SLE was obtained. The results were validated and compared with the original model performance...

  12. Morality Principles for Risk Modelling: Needs and Links with the Origins of Plausible Inference

    Science.gov (United States)

    Solana-Ortega, Alberto; Solana, Vicente

    2009-12-01

    In comparison with the foundations of probability calculus, the inescapable and controversial issue of how to assign probabilities has only recently become a matter of formal study. The introduction of information as a technical concept was a milestone, but the most promising entropic assignment methods still face unsolved difficulties, manifesting the incompleteness of plausible inference theory. In this paper we examine the situation faced by risk analysts in the critical field of extreme events modelling, where the former difficulties are especially visible, due to scarcity of observational data, the large impact of these phenomena and the obligation to assume professional responsibilities. To respond to the claim for a sound framework to deal with extremes, we propose a metafoundational approach to inference, based on a canon of extramathematical requirements. We highlight their strong moral content, and show how this emphasis in morality, far from being new, is connected with the historic origins of plausible inference. Special attention is paid to the contributions of Caramuel, a contemporary of Pascal, unfortunately ignored in the usual mathematical accounts of probability.

  13. ON THE DYNAMICS AND ORIGIN OF HAUMEA'S MOONS

    International Nuclear Information System (INIS)

    Ćuk, Matija; Ragozzine, Darin; Nesvorný, David

    2013-01-01

    The dwarf planet Haumea has two large satellites, Namaka and Hi'iaka, which orbit at relatively large separations. Both moons have significant eccentricities and inclinations in a pattern that is consistent with a past orbital resonance. Based on our analysis, we find that the present system is not consistent with satellite formation close to the primary and tidal evolution through mean-motion resonances. We propose that Namaka experienced only limited tidal evolution, leading to the mutual 8:3 mean-motion resonance which redistributed eccentricities and inclinations between the moons. This scenario requires that the original orbit of Hi'iaka was mildly eccentric; we propose that this eccentricity was either primordial or acquired through encounters with other trans-Neptunian objects. Both dynamical stability and our preferred tidal evolution model imply that the moons' masses are only about one-half of previously estimated values, suggesting high albedos and low densities. Because the present orbits of the moons strongly suggest formation from a flat disk close to their present locations, we conclude that Hi'iaka and Namaka may be second-generation moons, formed after the breakup of a larger past moon, previously proposed as the parent body of the Haumea family. We derive plausible parameters of that moon, consistent with the current models of Haumea's formation. An interesting implication of this hypothesis is that Hi'iaka and Namaka may orbit retrograde with respect to Haumea's spin. Retrograde orbits of Haumea's moons would be in full agreement with available observations and our dynamical analysis, and could provide a unique confirmation of the ''disrupted satellite'' scenario for the origin of the family

  14. The proposed 'concordance-statistic for benefit' provided a useful metric when modeling heterogeneous treatment effects.

    Science.gov (United States)

    van Klaveren, David; Steyerberg, Ewout W; Serruys, Patrick W; Kent, David M

    2018-02-01

    Clinical prediction models that support treatment decisions are usually evaluated for their ability to predict the risk of an outcome rather than treatment benefit-the difference between outcome risk with vs. without therapy. We aimed to define performance metrics for a model's ability to predict treatment benefit. We analyzed data of the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) trial and of three recombinant tissue plasminogen activator trials. We assessed alternative prediction models with a conventional risk concordance-statistic (c-statistic) and a novel c-statistic for benefit. We defined observed treatment benefit by the outcomes in pairs of patients matched on predicted benefit but discordant for treatment assignment. The 'c-for-benefit' represents the probability that from two randomly chosen matched patient pairs with unequal observed benefit, the pair with greater observed benefit also has a higher predicted benefit. Compared to a model without treatment interactions, the SYNTAX score II had improved ability to discriminate treatment benefit (c-for-benefit 0.590 vs. 0.552), despite having similar risk discrimination (c-statistic 0.725 vs. 0.719). However, for the simplified stroke-thrombolytic predictive instrument (TPI) vs. the original stroke-TPI, the c-for-benefit (0.584 vs. 0.578) was similar. The proposed methodology has the potential to measure a model's ability to predict treatment benefit not captured with conventional performance metrics. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Λ(t)CDM model as a unified origin of holographic and agegraphic dark energy models

    International Nuclear Information System (INIS)

    Chen Yun; Zhu Zonghong; Xu Lixin; Alcaniz, J.S.

    2011-01-01

    Motivated by the fact that any nonzero Λ can introduce a length scale or a time scale into Einstein's theory, r Λ =ct Λ =√(3/|Λ|). Conversely, any cosmological length scale or time scale can introduce a Λ(t), Λ(t)=3/r Λ 2 (t)=3/(c 2 t Λ 2 (t)). In this Letter, we investigate the time varying Λ(t) corresponding to the length scales, including the Hubble horizon, the particle horizon and the future event horizon, and the time scales, including the age of the universe and the conformal time. It is found out that, in this scenario, the Λ(t)CDM model can be taken as the unified origin of the holographic and agegraphic dark energy models with interaction between the matter and the dark energy, where the interacting term is determined by Q=-ρ . Λ . We place observational constraints on the Λ(t)CDM models originating from different cosmological length scales and time scales with the recently compiled 'Union2 compilation' which consists of 557 Type Ia supernovae (SNIa) covering a redshift range 0.015≤z≤1.4. In conclusion, an accelerating expansion universe can be derived in the cases taking the Hubble horizon, the future event horizon, the age of the universe and the conformal time as the length scale or the time scale.

  16. Historical Development of Origins Research

    Science.gov (United States)

    Lazcano, Antonio

    2010-01-01

    Following the publication of the Origin of Species in 1859, many naturalists adopted the idea that living organisms were the historical outcome of gradual transformation of lifeless matter. These views soon merged with the developments of biochemistry and cell biology and led to proposals in which the origin of protoplasm was equated with the origin of life. The heterotrophic origin of life proposed by Oparin and Haldane in the 1920s was part of this tradition, which Oparin enriched by transforming the discussion of the emergence of the first cells into a workable multidisciplinary research program. On the other hand, the scientific trend toward understanding biological phenomena at the molecular level led authors like Troland, Muller, and others to propose that single molecules or viruses represented primordial living systems. The contrast between these opposing views on the origin of life represents not only contrasting views of the nature of life itself, but also major ideological discussions that reached a surprising intensity in the years following Stanley Miller’s seminal result which showed the ease with which organic compounds of biochemical significance could be synthesized under putative primitive conditions. In fact, during the years following the Miller experiment, attempts to understand the origin of life were strongly influenced by research on DNA replication and protein biosynthesis, and, in socio-political terms, by the atmosphere created by Cold War tensions. The catalytic versatility of RNA molecules clearly merits a critical reappraisal of Muller’s viewpoint. However, the discovery of ribozymes does not imply that autocatalytic nucleic acid molecules ready to be used as primordial genes were floating in the primitive oceans, or that the RNA world emerged completely assembled from simple precursors present in the prebiotic soup. The evidence supporting the presence of a wide range of organic molecules on the primitive Earth, including membrane

  17. Modeling of carbon dioxide absorption by aqueous ammonia solutions using the Extended UNIQUAC model

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; van Well, Willy J. M.; Stenby, Erling Halfdan

    2010-01-01

    An upgraded version of the Extended UNIQUAC thermodynamic model for the carbon dioxide-ammonia-water system has been developed, based on the original version proposed by Thomsen and Rasmussen. The original model was valid in the temperature range 0-110°C, the pressure range 0-10 MPa...... properties of carbon dioxide and ammonia to supercritical conditions....

  18. Fetal Origins of Mental Health: The Developmental Origins of Health and Disease Hypothesis.

    Science.gov (United States)

    O'Donnell, Kieran J; Meaney, Michael J

    2017-04-01

    The quality of fetal growth and development predicts the risk for a range of noncommunicable, chronic illnesses. These observations form the basis of the "developmental origins of health and disease" hypothesis, which suggests that the intrauterine signals that compromise fetal growth also act to "program" tissue differentiation in a manner that predisposes to later illness. Fetal growth also predicts the risk for later psychopathology. These findings parallel studies showing that antenatal maternal emotional well-being likewise predicts the risk for later psychopathology. Taken together, these findings form the basis for integrative models of fetal neurodevelopment, which propose that antenatal maternal adversity operates through the biological pathways associated with fetal growth to program neurodevelopment. The authors review the literature and find little support for such integrated models. Maternal anxiety, depression, and stress all influence neurodevelopment but show modest, weak, or no associations with known stress mediators (e.g., glucocorticoids) or with fetal growth. Rather, compromised fetal development appears to establish a "meta-plastic" state that increases sensitivity to postnatal influences. There also remain serious concerns that observational studies associating either fetal growth or maternal mental health with neurodevelopmental outcomes fail to account for underlying genetic factors. Finally, while the observed relation between fetal growth and adult health has garnered considerable attention, the clinical relevance of these associations remains to be determined. There are both considerable promise and important challenges for future studies of the fetal origins of mental health.

  19. IMPROVING THE INTEROPERABILITY OF DISASTER MODELS: A CASE STUDY OF PROPOSING FIREML FOR FOREST FIRE MODEL

    Directory of Open Access Journals (Sweden)

    W. Jiang

    2018-04-01

    Full Text Available This paper presents a new standardized data format named Fire Markup Language (FireML, extended by the Geography Markup Language (GML of OGC, to elaborate upon the fire hazard model. The proposed FireML is able to standardize the input and output documents of a fire model for effectively communicating with different disaster management systems to ensure a good interoperability. To demonstrate the usage of FireML and testify its feasibility, an adopted forest fire spread model being compatible with FireML is described. And a 3DGIS disaster management system is developed to simulate the dynamic procedure of forest fire spread with the defined FireML documents. The proposed approach will enlighten ones who work on other disaster models' standardization work.

  20. Improving the Interoperability of Disaster Models: a Case Study of Proposing Fireml for Forest Fire Model

    Science.gov (United States)

    Jiang, W.; Wang, F.; Meng, Q.; Li, Z.; Liu, B.; Zheng, X.

    2018-04-01

    This paper presents a new standardized data format named Fire Markup Language (FireML), extended by the Geography Markup Language (GML) of OGC, to elaborate upon the fire hazard model. The proposed FireML is able to standardize the input and output documents of a fire model for effectively communicating with different disaster management systems to ensure a good interoperability. To demonstrate the usage of FireML and testify its feasibility, an adopted forest fire spread model being compatible with FireML is described. And a 3DGIS disaster management system is developed to simulate the dynamic procedure of forest fire spread with the defined FireML documents. The proposed approach will enlighten ones who work on other disaster models' standardization work.

  1. Proposal for product development model focused on ce certification methodology

    Directory of Open Access Journals (Sweden)

    Nathalia Marcia Goulart Pinheiro

    2015-09-01

    Full Text Available This paper presents a critical analysis comparing 21 product development models in order to identify whether these structures meet the demands Product Certification of the European Community (CE. Furthermore, it presents a product development model, comprising the steps in the models analyzed, including improvements in activities for referred product certification. The proposed improvements are justified by the growing quest for the internationalization of products and processes within companies.

  2. The 'OMITRON' and 'MODEL OMITRON' proposed experiments

    International Nuclear Information System (INIS)

    Sestero, A.

    1997-12-01

    In the present paper the main features of the OMITRON and MODEL OMITRON proposed high field tokamaks are illustrated. Of the two, OMITRON is an ambitious experiment, aimed at attaining plasma burning conditions. its key physics issues are discussed, and a comparison is carried out with corresponding physics features in ignition experiments such as IGNITOR and ITER. Chief asset and chief challenge - in both OMITRON and MODEL OMITRON is the conspicuous 20 Tesla toroidal field value on the plasma axis. The advanced features of engineering which consent such a reward in terms of toroidal magnet performance are discussed in convenient depth and detail. As for the small, propaedeutic device MODEL OMITRON among its goals one must rank the purpose of testing key engineering issues in vivo, which are vital for the larger and more expensive parent device. Besides that, however - as indicated by ad hoc performed scoping studies - the smaller machine is found capable also of a number of quite interesting physics investigations in its own right

  3. Original Product Resolution (OPR) Source Digital Elevation Models (DEMs) - USGS National Map 3DEP Downloadable Data Collection

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data collection is the Original Product Resolution (OPR) Digital Elevation Model (DEM) as provided to the USGS. This DEM is delivered in the original...

  4. DEVELOPING A MATHEMATICAL MODEL FOR THE PROCESS OF DEVELOPING A MATHEMATICAL MODEL FOR THE PROCESS OF SEDIMENTARY TANKS

    Directory of Open Access Journals (Sweden)

    Valeria Victoria IOVANOV

    2013-05-01

    Full Text Available The model is reformulated by means of stochastic differential equations, and the parametersare estimated by a maximum likelihood method.VESILIND (1968; 1979 proposed a sludge settling velocity model of exponential form. During recent years,several refinements to the original model have been proposed, see e.g. GRIJSPEERDT et al. (1995; DUPONTand DAHL (1995 EKAMA et al. (1997. In the proposed models several layers in the settling tank areincorporated to permit the calculation of SS profiles over the tank depth and predict the SS concentrations in thereturn sludge and in the effluent from the clarifier.Here, the original VESILIND model combined with a simple suction depth model is used to enable predictionof the SS concentration in the effluent from the tank. In order to make the model applicable for real time controlpurposes, only two layers of variable height in the tank are considered

  5. [Impact of small-area context on health: proposing a conceptual model].

    Science.gov (United States)

    Voigtländer, S; Mielck, A; Razum, O

    2012-11-01

    Recent empirical studies stress the impact of features related to the small-area context on individual health. However, so far there exists no standard explanatory model that integrates the different kinds of such features and that conceptualises their relation to individual characteristics of social inequality. A review of theoretical publications on the relationship between social position and health as well as existing conceptual models for the impact of features related to the small-area context on health was undertaken. In the present article we propose a conceptual model for the health impact of the small-area context. This model conceptualises the location of residence as one dimension of social inequality that affects health through the resources as well as stressors which are inherent in the small-area context. The proposed conceptual model offers an orientation for future empirical studies and can serve as a basis for further discussions concerning the health relevance of the small-area context. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Non-monotonic reasoning in conceptual modeling and ontology design: A proposal

    CSIR Research Space (South Africa)

    Casini, G

    2013-06-01

    Full Text Available -1 2nd International Workshop on Ontologies and Conceptual Modeling (Onto.Com 2013), Valencia, Spain, 17-21 June 2013 Non-monotonic reasoning in conceptual modeling and ontology design: A proposal Giovanni Casini1 and Alessandro Mosca2 1...

  7. Proposal for a Method for Business Model Performance Assessment: Toward an Experimentation Tool for Business Model Innovation

    Directory of Open Access Journals (Sweden)

    Antonio Batocchio

    2017-04-01

    Full Text Available The representation of business models has been recently widespread, especially in the pursuit of innovation. However, defining a company’s business model is sometimes limited to discussion and debates. This study observes the need for performance measurement so that business models can be data-driven. To meet this goal, the work proposed as a hypothesis the creation of a method that combines the practices of the Balanced Scorecard with a method of business models representation – the Business Model Canvas. Such a combination was based on study of conceptual adaptation, resulting in an application roadmap. A case study application was performed to check the functionality of the proposition, focusing on startup organizations. It was concluded that based on the performance assessment of the business model it is possible to propose the search for change through experimentation, a path that can lead to business model innovation.

  8. A model for the origin of solar wind stream interfaces

    International Nuclear Information System (INIS)

    Hundhausen, A.J.; Burlaga, L.F.

    1975-01-01

    The basic variations in solar wind properties that have been observed at 'stream interfaces' near 1 AU are explained by a gas dynamic model in which a radially propagating stream, produced by a temperature variation in the solar envelope, steepens nonlinearly while moving through interplanetary space. The region thus identified with the stream interface separates the ambient solar wind from the fresh hot material originally in the stream. However, the interface regions given by the present model are thicker than most stream interfaces observed in the solar wind, a fact suggesting that some additional physical process may be important in determining that thickness. Variations in the density, speed, or Alfven pressure alone appear not to produce streams with such an interface

  9. Proposed higher order continuum-based models for an elastic ...

    African Journals Online (AJOL)

    Three new variants of continuum-based models for an elastic subgrade are proposed. The subgrade is idealized as a homogenous, isotropic elastic layer of thickness H overlying a firm stratum. All components of the stress tensor in the subgrade are taken into account. Reasonable assumptions are made regarding the ...

  10. The Origin of Species

    NARCIS (Netherlands)

    Darwin, Charles

    2005-01-01

    In The Origin of Species Darwin outlined his theory of evolution, which proposed that species had been evolving and differentiating over time under the influence of natural selection. On its publication it became hugely influential, bringing about a seismic shift in the scientific view of humanitys

  11. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins

    OpenAIRE

    Camina, Eduardo; Güell, Francisco

    2017-01-01

    This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and...

  12. Testing a Model of Resistance to Peer Pressure among Mexican-Origin Adolescents

    Science.gov (United States)

    Bamaca, Mayra Y.; Umana-Taylor, Adriana J.

    2006-01-01

    This study examined the factors associated with resistance to peer pressure toward antisocial behaviors among a sample of Mexican-origin adolescents (n=564) living in a large Southwestern city in the U.S. A model examining the influence of generational status, emotional autonomy from parents, and self-esteem on resistance to peer pressure was…

  13. A proposal for operator team behavior model and operator's thinking mechanism

    International Nuclear Information System (INIS)

    Yoshimura, Seiichi; Takano, Kenichi; Sasou, Kunihide

    1995-01-01

    Operating environment in huge systems like nuclear power plants or airplanes is changing rapidly with the advance of computer technology. It is necessary to elucidate thinking process of operators and decision-making process of an operator team in abnormal situations, in order to prevent human errors under such environment. The Central Research Institute of Electric Power Industry is promoting a research project to establish human error prevention countermeasures by modeling and simulating the thinking process of operators and decision-making process of an operator team. In the previous paper, application of multilevel flow modeling was proposed to a mental model which conducts future prediction and cause identification, and the characteristics were verified by experienced plant operators. In this paper, an operator team behavior model and a fundamental operator's thinking mechanism especially 'situation understanding' are proposed, and the proposals are evaluated by experiments using a full-scale simulator. The results reveal that some assumptions such as 'communication is done between a leader and a follower' are almost appropriate and that the situation understanding can be represented by 'probable candidates for cause, determination of a parameter which changes when an event occurs, determination of parameters which are influenced by the change of the previous parameter, determination of a principal parameter and future prediction of the principal parameter'. (author)

  14. Generating original ideas: The neural underpinning of originality.

    Science.gov (United States)

    Mayseless, Naama; Eran, Ayelet; Shamay-Tsoory, Simone G

    2015-08-01

    One of the key aspects of creativity is the ability to produce original ideas. Originality is defined in terms of the novelty and rarity of an idea and is measured by the infrequency of the idea compared to other ideas. In the current study we focused on divergent thinking (DT) - the ability to produce many alternate ideas - and assessed the neural pathways associated with originality. Considering that generation of original ideas involves both the ability to generate new associations and the ability to overcome automatic common responses, we hypothesized that originality would be associated with activations in regions related to associative thinking, including areas of the default mode network (DMN) such as medial prefrontal areas, as well as with areas involved in cognitive control and inhibition. Thirty participants were scanned while performing a DT task that required the generation of original uses for common objects. The results indicate that the ability to produce original ideas is mediated by activity in several regions that are part of the DMN including the medial prefrontal cortex (mPFC) and the posterior cingulate cortex (PCC). Furthermore, individuals who are more original exhibited enhanced activation in the ventral anterior cingulate cortex (vACC), which was also positively coupled with activity in the left occipital-temporal area. These results are in line with the dual model of creativity, according to which original ideas are a product of the interaction between a system that generates ideas and a control system that evaluates these ideas. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Can a linguistic serial founder effect originating in Africa explain the worldwide phonemic cline?

    Science.gov (United States)

    Fort, Joaquim; Pérez-Losada, Joaquim

    2016-04-01

    It has been proposed that a serial founder effect could have caused the present observed pattern of global phonemic diversity. Here we present a model that simulates the human range expansion out of Africa and the subsequent spatial linguistic dynamics until today. It does not assume copying errors, Darwinian competition, reduced contrastive possibilities or any other specific linguistic mechanism. We show that the decrease of linguistic diversity with distance (from the presumed origin of the expansion) arises under three assumptions, previously introduced by other authors: (i) an accumulation rate for phonemes; (ii) small phonemic inventories for the languages spoken before the out-of-Africa dispersal; (iii) an increase in the phonemic accumulation rate with the number of speakers per unit area. Numerical simulations show that the predictions of the model agree with the observed decrease of linguistic diversity with increasing distance from the most likely origin of the out-of-Africa dispersal. Thus, the proposal that a serial founder effect could have caused the present observed pattern of global phonemic diversity is viable, if three strong assumptions are satisfied. © 2016 The Authors.

  16. Can a linguistic serial founder effect originating in Africa explain the worldwide phonemic cline?

    Science.gov (United States)

    2016-01-01

    It has been proposed that a serial founder effect could have caused the present observed pattern of global phonemic diversity. Here we present a model that simulates the human range expansion out of Africa and the subsequent spatial linguistic dynamics until today. It does not assume copying errors, Darwinian competition, reduced contrastive possibilities or any other specific linguistic mechanism. We show that the decrease of linguistic diversity with distance (from the presumed origin of the expansion) arises under three assumptions, previously introduced by other authors: (i) an accumulation rate for phonemes; (ii) small phonemic inventories for the languages spoken before the out-of-Africa dispersal; (iii) an increase in the phonemic accumulation rate with the number of speakers per unit area. Numerical simulations show that the predictions of the model agree with the observed decrease of linguistic diversity with increasing distance from the most likely origin of the out-of-Africa dispersal. Thus, the proposal that a serial founder effect could have caused the present observed pattern of global phonemic diversity is viable, if three strong assumptions are satisfied. PMID:27122180

  17. Parental Modeling and Deidentification in Romantic Relationships Among Mexican-origin Youth.

    Science.gov (United States)

    Kuo, Sally I-Chun; Wheeler, Lorey A; Updegraff, Kimberly A; McHale, Susan M; Umaña-Taylor, Adriana J; Perez-Brena, Norma J

    2017-10-01

    This study investigated youth's modeling of and de-identification from parents in romantic relationships, using two phases of data from adolescent siblings, mothers, and fathers in 246 Mexican-origin families. Each parent reported his/her marital satisfaction and conflict, and youth reported on parent-adolescent warmth and conflict at Time 1. Youth's reports of modeling of and de-identification from their mothers and fathers and three romantic relationship outcomes were assessed at Time 2. Findings revealed that higher parental marital satisfaction, lower marital conflict, and higher warmth and lower conflict in parent-adolescent relationships were associated with more modeling and less de-identification from parents. Moreover, higher de-identification was linked to a greater likelihood of youth being involved in a romantic relationship and cohabitation, whereas more modeling was linked to a lower likelihood of cohabitation and older age of first sex. Discussion underscores the importance of assessing parental modeling and de-identification and understanding correlates of these processes.

  18. Mapping replication origins in yeast chromosomes.

    Science.gov (United States)

    Brewer, B J; Fangman, W L

    1991-07-01

    The replicon hypothesis, first proposed in 1963 by Jacob and Brenner, states that DNA replication is controlled at sites called origins. Replication origins have been well studied in prokaryotes. However, the study of eukaryotic chromosomal origins has lagged behind, because until recently there has been no method for reliably determining the identity and location of origins from eukaryotic chromosomes. Here, we review a technique we developed with the yeast Saccharomyces cerevisiae that allows both the mapping of replication origins and an assessment of their activity. Two-dimensional agarose gel electrophoresis and Southern hybridization with total genomic DNA are used to determine whether a particular restriction fragment acquires the branched structure diagnostic of replication initiation. The technique has been used to localize origins in yeast chromosomes and assess their initiation efficiency. In some cases, origin activation is dependent upon the surrounding context. The technique is also being applied to a variety of eukaryotic organisms.

  19. General Friction Model Extended by the Effect of Strain Hardening

    DEFF Research Database (Denmark)

    Nielsen, Chris V.; Martins, Paulo A.F.; Bay, Niels

    2016-01-01

    An extension to the general friction model proposed by Wanheim and Bay [1] to include the effect of strain hardening is proposed. The friction model relates the friction stress to the fraction of real contact area by a friction factor under steady state sliding. The original model for the real...... contact area as function of the normalized contact pressure is based on slip-line analysis and hence on the assumption of rigid-ideally plastic material behavior. In the present work, a general finite element model is established to, firstly, reproduce the original model under the assumption of rigid...

  20. Origin of Money: Dynamic Duality Between Necessity and Unnecessity

    Science.gov (United States)

    Tauchi, Yuka; Kamiura, Moto; Haruna, Taichi; Gunji, Yukio-Pegio

    2008-10-01

    We propose a mathematical model of economic agents to study origin of money. This multi-agent model is based on commodity theory of money, which says that a commodity used as money emerges from barter transaction. Each agent has a different value system which is given by a Heyting algebra, and exchanges one's commodities based on the value system. In each value system, necessity and unnecessity of commodities are expressed by some elements and their compliments on a Heyting Algebra. Moreover, the concept of the compliment is extended. Consequently, the duality of the necessity-unnecessity is weakened, and the exchanges of the commodities are promoted. The commodities which keeps being exchanged for a long time can correspond to money.

  1. Bayesian inference of chemical kinetic models from proposed reactions

    KAUST Repository

    Galagali, Nikhil

    2015-02-01

    © 2014 Elsevier Ltd. Bayesian inference provides a natural framework for combining experimental data with prior knowledge to develop chemical kinetic models and quantify the associated uncertainties, not only in parameter values but also in model structure. Most existing applications of Bayesian model selection methods to chemical kinetics have been limited to comparisons among a small set of models, however. The significant computational cost of evaluating posterior model probabilities renders traditional Bayesian methods infeasible when the model space becomes large. We present a new framework for tractable Bayesian model inference and uncertainty quantification using a large number of systematically generated model hypotheses. The approach involves imposing point-mass mixture priors over rate constants and exploring the resulting posterior distribution using an adaptive Markov chain Monte Carlo method. The posterior samples are used to identify plausible models, to quantify rate constant uncertainties, and to extract key diagnostic information about model structure-such as the reactions and operating pathways most strongly supported by the data. We provide numerical demonstrations of the proposed framework by inferring kinetic models for catalytic steam and dry reforming of methane using available experimental data.

  2. THE PROPOSED MODEL OF COLLABORATIVE VIRTUAL LEARNING ENVIRONMENT FOR INTRODUCTORY PROGRAMMING COURSE

    Directory of Open Access Journals (Sweden)

    Mahfudzah OTHMAN

    2012-01-01

    Full Text Available This paper discusses the proposed model of the collaborative virtual learning system for the introductory computer programming course which uses one of the collaborative learning techniques known as the “Think-Pair-Share”. The main objective of this study is to design a model for an online learning system that facilitates the collaborative learning activities in a virtual environment such as online communications and pair or small group discussions. In order to model the virtual learning environment, the RUP methodology has been used where it involves the data collection phase and the analysis and design phase. Fifty respondents have been randomly selected to participate in the data collection phase to investigate the students’ interest and learning styles as well as their learning preferences. The results have shown the needs for the development of online small group discussions that can be used as an alternative learning style for programming courses. The proposed design of the virtual learning system named as the Online Collaborative Learning System or OCLS is being depicted using the object-oriented models which are the use-case model and class diagram in order to show the concise processes of virtual “Think-Pair-Share” collaborative activities. The “Think-Pair-Share” collaborative learning technique that is being used in this model has been chosen because of its simplicity and relatively low-risk. This paper also presents the proposed model of the system’s architecture that will become the guidelines for the physical development of OCLS using the web-based applications.

  3. Guinea pig models for translation of the developmental origins of health and disease hypothesis into the clinic.

    Science.gov (United States)

    Morrison, Janna L; Botting, Kimberley J; Darby, Jack R T; David, Anna L; Dyson, Rebecca M; Gatford, Kathryn L; Gray, Clint; Herrera, Emilio A; Hirst, Jonathan J; Kim, Bona; Kind, Karen L; Krause, Bernardo J; Matthews, Stephen G; Palliser, Hannah K; Regnault, Timothy R H; Richardson, Bryan S; Sasaki, Aya; Thompson, Loren P; Berry, Mary J

    2018-04-06

    Over 30 years ago Professor David Barker first proposed the theory that events in early life could explain an individual's risk of non-communicable disease in later life: the developmental origins of health and disease (DOHaD) hypothesis. During the 1990s the validity of the DOHaD hypothesis was extensively tested in a number of human populations and the mechanisms underpinning it characterised in a range of experimental animal models. Over the past decade, researchers have sought to use this mechanistic understanding of DOHaD to develop therapeutic interventions during pregnancy and early life to improve adult health. A variety of animal models have been used to develop and evaluate interventions, each with strengths and limitations. It is becoming apparent that effective translational research requires that the animal paradigm selected mirrors the tempo of human fetal growth and development as closely as possible so that the effect of a perinatal insult and/or therapeutic intervention can be fully assessed. The guinea pig is one such animal model that over the past two decades has demonstrated itself to be a very useful platform for these important reproductive studies. This review highlights similarities in the in utero development between humans and guinea pigs, the strengths and limitations of the guinea pig as an experimental model of DOHaD and the guinea pig's potential to enhance clinical therapeutic innovation to improve human health. © 2018 The Authors. The Journal of Physiology © 2018 The Physiological Society.

  4. Origin of Evolution versus Origin of Life: A Shift of Paradigm

    Directory of Open Access Journals (Sweden)

    Marc Tessera

    2011-06-01

    Full Text Available The question of the primordial ancestor must be approached through the search for the origin of evolution, not through the search for the origin of life. There is a major issue with the concept of life because it is impossible to define, thus is not a scientific but a metaphysical concept. On the contrary, evolution may be defined by as few as three conditions. These do not necessarily involve biopolymers. However, such an approach must give clues to explain the emergence of distinct lineages to allow Darwinian natural selection. A plausible solution exists within an autotrophic lipidic vesicle-based model that is presented. The model requires the existence of hydrothermal sites such as the Lost City Hydrothermal Field leading to specific constraints. For this reason Mars and Europa may be questioned as possible cradles of evolution. If we replace the search for the origin of life by the one for the origin of evolution our priority first is to find a consensus on the minimal conditions that would allow evolution to emerge and persist anywhere in the universe.

  5. The evaluation of doctoral thesis. A model proposal

    Directory of Open Access Journals (Sweden)

    de-Miguel, Mario

    2010-04-01

    Full Text Available The aim of this work is the development of a model that can be used as a framework for evaluators and PhD tribunal members, either during the previous administrative processing phase or at the actual exposition and viva on doctoral dissertations. To this end, once reviewed the existing literature and normative, a new proposal is laid out on the main aspects and criteria to be analysed and assessed from any given scientific work, thus introducing a tool that facilitates and specifies this work. Our model is intended to be an open proposal on which we would welcome any contribution and suggestion. El objetivo del presente trabajo es la elaboración de un modelo que pueda ser utilizado como marco de referencia por los evaluadores y miembros de tribunales de las tesis doctorales tanto en la fase previa a la tramitación administrativa como en el acto de exposición y defensa de la misma. Para ello, una vez revisada la literatura y la normativa vigente al respecto, efectuamos una propuesta sobre los principales aspectos y criterios que deben ser objeto de análisis y valoración en todo trabajo científico, y presentamos una herramienta que facilita y precisa esta tarea. Nuestro modelo constituye una propuesta abierta sobre la que esperamos aportaciones y sugerencias.

  6. On the tsunami model of the origin of multi-ring basins

    International Nuclear Information System (INIS)

    Yue Zengyuan; Zhang Bin; Chen Daohan.

    1990-03-01

    By use of the theory of shallow water waves generated by an impulsive pressure, the tsunami theory of the origin of multi-ring basins is rediscussed and an approximate formula used for calculating the ring location is derived. From the computed ring spacing of three multi-ring basins on the moon (Orientale, Moscoviense and Serenitatis South), it is shown that the tsunami model can only be applied to the area within the IV ring which signifies the rim of the excavated basin and the end of the fluidized region. In the frame of the tsunami model, no explanation for ring spacing is equally plausible for exterior rings as well as interior ones. (author). 14 refs, 1 tab

  7. Media Accountability Systems: Models, proposals and outlooks

    Directory of Open Access Journals (Sweden)

    Luiz Martins da Silva

    2007-06-01

    Full Text Available This paper analyzes one of the basic actions of SOS-Imprensa, the mechanism to assure Media Accountability with the goal of proposing a synthesis of models for the Brazilian reality. The article aims to address the possibilities of creating and improving mechanisms to stimulate the democratic press process and to mark out and assure freedom of speech and personal rights with respect to the media. Based on the Press Social Responsibility Theory, the hypothesis is that the experiences analyzed (Communication Council, Press Council, Ombudsman and Readers Council are alternatives for accountability, mediation and arbitration, seeking visibility, trust and public support in favor of fairer media.

  8. The Motivational Knowledge Management Model: proposal to apply it in the library sector

    Directory of Open Access Journals (Sweden)

    Daniel López-Fernández

    2016-12-01

    Full Text Available In professional environments, attention paid to aspects such as supervisory styles, interpersonal relationships and workers eagerness can have a positive impact on employee motivation and, consequently, on their performance and well-being. To achieve this, knowledge management models such as those presented here can be applied. This model generates diagnoses of motivation and recommendations for improvement, both systematically and scientifically. Consequently, it is especially useful for managers and human resource departments. The proposed model can be adapted to different kinds of professional groups, including those in library and documentation services. The suitability, reliability and usefulness of the proposed model have been empirically checked through case studies with 92 students and 166 professionals. The positive results allow us to conclude that the model is effective and useful for assessing and improving motivation.

  9. Determination of Original Infection Source of H7N9 Avian Influenza by Dynamical Model

    Science.gov (United States)

    Zhang, Juan; Jin, Zhen; Sun, Gui-Quan; Sun, Xiang-Dong; Wang, You-Ming; Huang, Baoxu

    2014-05-01

    H7N9, a newly emerging virus in China, travels among poultry and human. Although H7N9 has not aroused massive outbreaks, recurrence in the second half of 2013 makes it essential to control the spread. It is believed that the most effective control measure is to locate the original infection source and cut off the source of infection from human. However, the original infection source and the internal transmission mechanism of the new virus are not totally clear. In order to determine the original infection source of H7N9, we establish a dynamical model with migratory bird, resident bird, domestic poultry and human population, and view migratory bird, resident bird, domestic poultry as original infection source respectively to fit the true dynamics during the 2013 pandemic. By comparing the date fitting results and corresponding Akaike Information Criterion (AIC) values, we conclude that migrant birds are most likely the original infection source. In addition, we obtain the basic reproduction number in poultry and carry out sensitivity analysis of some parameters.

  10. An intermittency model for predicting roughness induced transition

    Science.gov (United States)

    Ge, Xuan; Durbin, Paul

    2014-11-01

    An extended model for roughness-induced transition is proposed based on an intermittency transport equation for RANS modeling formulated in local variables. To predict roughness effects in the fully turbulent boundary layer, published boundary conditions for k and ω are used, which depend on the equivalent sand grain roughness height, and account for the effective displacement of wall distance origin. Similarly in our approach, wall distance in the transition model for smooth surfaces is modified by an effective origin, which depends on roughness. Flat plate test cases are computed to show that the proposed model is able to predict the transition onset in agreement with a data correlation of transition location versus roughness height, Reynolds number, and inlet turbulence intensity. Experimental data for a turbine cascade are compared with the predicted results to validate the applicability of the proposed model. Supported by NSF Award Number 1228195.

  11. A proposal for a typology of sharing economy

    Directory of Open Access Journals (Sweden)

    Maira Petrini

    2017-10-01

    Full Text Available Purpose: to propose a typology for sharing economy that allows the characterization and classification of its main forms of manifestation. Originality/value: the theme that involves collaborative consumption and sharing economy has wide definitions with no clear establishment of boundaries between them. Part of that definition gap may occur because of the recent emergency of literature on sharing economy. Additionally, the fact that sharing economy and collaborative consumption are the newest buzzwords, several businesses started calling themselves as such. Design/methodology/approach: from the review of the literature, 11 characteristics that describe the theme were identified. In the light of those characteristics, 72 collaborative consumption websites were analyzed, representatives of the 24 collaborative consumption categories proposed by Botsman and Rogers (2010. Findings: three archetypes were identified: 1. new business models represent the new players based on technological platforms, which are the core business of the company, and generate income by charging service fees; 2. redesigned businesses are traditional market models redesigned to present time and price advantages to the consumer; 3. sharing by ideal is the archetype that best represents sustainable consumption alternative models.

  12. Patent portfolio management: literature review and a proposed model.

    Science.gov (United States)

    Conegundes De Jesus, Camila Kiyomi; Salerno, Mario Sergio

    2018-05-09

    Patents and patent portfolios are gaining attention in the last decades, from the called 'pro-patent era' to the recent billionaire transactions involving patent portfolios. The field is growing in importance, both theoretically and practically and despite having substantial literature on new product development portfolio management, we have not found an article relating this theory to patent portfolios. Areas covered: The paper develops a systematic literature review on patent portfolio management to organize the evolution and tendencies of patent portfolio management, highlighting distinctive features of patent portfolio management. Interview with IP manager of three life sciences companies, including a leading multinational group provided relevant information about patent portfolio management. Expert opinion: Based on the systematic literature review on portfolio management, more specifically, on new product development portfolio theory, and interview the paper proposes the paper proposes a reference model to manage patent portfolios. The model comprises four stages aligned with the three goals of the NPD portfolio management: 1 - Linking strategy of the Company's NPD Portfolio to Patent Portfolio; 2 - Balancing the portfolio in buckets; 3 - Patent Valuation (maximizing valuation); 4 - Regularly reviewing the patent portfolio.

  13. A new conceptual model for whole mantle convection and the origin of hotspot plumes

    Science.gov (United States)

    Yoshida, Masaki

    2014-08-01

    A new conceptual model of mantle convection is constructed for consideration of the origin of hotspot plumes, using recent evidence from seismology, high-pressure experiments, geodynamic modeling, geoid inversion studies, and post-glacial rebound analyses. This conceptual model delivers several key points. Firstly, some of the small-scale mantle upwellings observed as hotspots on the Earth's surface originate at the base of the mantle transition zone (MTZ), in which the Archean granitic continental material crust (TTG; tonalite-trondhjemite-granodiorite) with abundant radiogenic elements is accumulated. Secondly, the TTG crust and the subducted oceanic crust that have accumulated at the base of MTZ could act as thermal or mechanical insulators, leading to the formation of a hot and less viscous layer just beneath the MTZ; which may enhance the instability of plume generation at the base of the MTZ. Thirdly, the origin of some hotspot plumes is isolated from the large low shear-wave velocity provinces (LLSVPs) under Africa and the South Pacific. I consider that the conceptual model explains why almost all the hotspots around Africa are located above the margins of the African LLSVP. Because a planetary-scale trench system surrounding a “Pangean cell” has been spatially stable throughout the Phanerozoic, a large amount of the oceanic crustal layer is likely to be trapped in the MTZ under the Pangean cell. Therefore, under Africa, almost all of the hotspot plumes originate from the base of the MTZ, where a large amount of TTG and/or oceanic crusts has accumulated. This conceptual model may explain the fact that almost all the hotspots around Africa are located on margins above the African LLSVP. It is also considered that some of the hotspot plumes under the South Pacific thread through the TTG/oceanic crusts accumulated around the bottom of the MTZ, and some have their roots in the South Pacific LLSVP while others originate from the MTZ. The numerical simulations

  14. Thermal explosion models

    Energy Technology Data Exchange (ETDEWEB)

    Ping, Tso Chin [Malaya Univ., Kuala Lumpur (Malaysia)

    1984-12-01

    The phenomenon of thermal explosion arises in several important safety problems, yet scientists are still baffled by its origin. This article reviews some of the models that have been proposed to explain the phenomenon.

  15. Cultural Socialization and Ethnic Pride among Mexican-Origin Adolescents during the Transition to Middle School

    Science.gov (United States)

    Hernández, Maciel M.; Conger, Rand D.; Robins, Richard W.; Bacher, Kelly Beaumont; Widaman, Keith F.

    2014-01-01

    The relation between cultural socialization and ethnic pride during the transition to middle school was examined for 674 fifth-grade students (50% boys; M[subscript age] = 10.4 years) of Mexican origin. The theoretical model guiding the study proposes that parent-child relationship quality is a resource in the transmission of cultural values from…

  16. On the Origins of Mars' Exospheric Nonthermal Oxygen Component as Observed by MAVEN and Modeled by HELIOSARES

    Science.gov (United States)

    Leblanc, F.; Chaufray, J. Y.; Modolo, R.; Leclercq, L.; Curry, S.; Luhmann, J.; Lillis, R.; Hara, T.; McFadden, J.; Halekas, J.; Schneider, N.; Deighan, J.; Mahaffy, P. R.; Benna, M.; Johnson, R. E.; Gonzalez-Galindo, F.; Forget, F.; Lopez-Valverde, M. A.; Eparvier, F. G.; Jakosky, B.

    2017-12-01

    The first measurements of the emission brightness of the oxygen atomic exosphere by Mars Atmosphere and Volatile EvolutioN (MAVEN) mission have clearly shown that it is composed of a thermal component produced by the extension of the upper atmosphere and of a nonthermal component. Modeling these measurements allows us to constrain the origins of the exospheric O and, as a consequence, to estimate Mars' present oxygen escape rate. We here propose an analysis of three periods of MAVEN observations based on a set of three coupled models: a hybrid magnetospheric model (LATmos HYbrid Simulation (LatHyS)), an Exospheric General Model (EGM), and the Global Martian Circulation model of the Laboratoire de Météorologie Dynamique (LMD-GCM), which provide a description of Mars' environment from the surface up to the solar wind. The simulated magnetosphere by LatHyS is in good agreement with MAVEN Plasma and Field Package instruments data. The LMD-GCM modeled upper atmospheric profiles for the main neutral and ion species are compared to Neutral Gas and Ion Mass Spectrometer/MAVEN data showing that the LMD-GCM can provide a satisfactory global view of Mars' upper atmosphere. Finally, we were able to reconstruct the expected emission brightness intensity from the oxygen exosphere using EGM. The good agreement with the averaged measured profiles by Imaging Ultraviolet Spectrograph during these three periods suggests that Mars' exospheric nonthermal component can be fully explained by the reactions of dissociative recombination of the O2+ ion in Mars' ionosphere, limiting significantly our ability to extract information from MAVEN observations of the O exosphere on other nonthermal processes, such as sputtering.

  17. Mathematical Modeling of the Origins of Life

    Science.gov (United States)

    Pohorille, Andrew

    2006-01-01

    The emergence of early metabolism - a network of catalyzed chemical reactions that supported self-maintenance, growth, reproduction and evolution of the ancestors of contemporary cells (protocells) was a critical, but still very poorly understood step on the path from inanimate to animate matter. Here, it is proposed and tested through mathematical modeling of biochemically plausible systems that the emergence of metabolism and its initial evolution towards higher complexity preceded the emergence of a genome. Even though the formation of protocellular metabolism was driven by non-genomic, highly stochastic processes the outcome was largely deterministic, strongly constrained by laws of chemistry. It is shown that such concepts as speciation and fitness to the environment, developed in the context of genomic evolution, also held in the absence of a genome.

  18. Thermal explosion models

    International Nuclear Information System (INIS)

    Tso Chin Ping

    1984-01-01

    The phenomenon of thermal explosion arises in several important safety problems, yet scientists are still baffled by its origin. This article reviews some of the models that have been proposed to explain the phenomenon. (author)

  19. Proposal of a theoretical model for the practical nurse

    Directory of Open Access Journals (Sweden)

    Dolores Abril Sabater

    2010-01-01

    Full Text Available AIM: To determine which model of nursing is proposed by care professionals and the reason for their choice. METHOD: cross-sectional, descriptive study design. The main variable: Nursing Models and Theories. As secondary variables were collected: age, gender, years of work experience, nursing model of basic training, and course/s related. We used a self-elaborated, anonymous questionnaire, passed between April - May, 2006. Not random sample.RESULTS: 546 nurses were invited, answered 205. 38 % response rate. Virginia Henderson was the more selected model (33%, however, 42% left the question blank, 12% indicated that they wanted to work under the guidance of a model. They selected a specifically model: Knowledge of the model to their training, standardization in other centers, the characteristics of the model itself and identification with its philosophy. They are not decided by a model by ignorance, lack of time and usefulness. CONCLUSIONS: The model chosen mostly for their daily work was Virginia Henderson model, so that knowledge of a model is the main reason for their election. Professionals who choose not to use the model in their practice realize offers and calling for resources, besides to explain the lack of knowledge on this topic. To advance the nursing profession is necessary that nurse is thought over widely on the abstract concepts of the theory in our context.

  20. Dynamic processes in technological systems of machining and the nature of their origin

    Science.gov (United States)

    Ershov, D. Y.; Zlotnikov, E. G.; Koboyankwe, L. E.

    2017-10-01

    The article describes the main causes of dynamic processes in technological systems, the types of vibrations that occur in machines, external sources that cause fluctuations in the machine bases. The article discusses the occurrence of self-oscillations in the machines. The authors proposed a mathematical model of a multi-mass technological system based on the example of a vertical drilling machine. The original multi-mass oscillatory system is replaced by a simplified three-mass model, which allows considering the low-frequency range of workloads and disturbing external influences.

  1. Proposal of a Model for effective Management and Development of virtual Teams

    Directory of Open Access Journals (Sweden)

    Petr Skyrik

    2010-10-01

    Full Text Available The main aim of this paper is to present a pilot proposal of a model of “Virtual Development Management System” (ViDeMaS which will facilitate more effective management and development of virtual teams. Management and development of virtual teams is not a simple concept. It comprises a body of knowledge from a number of fields and scientific disciplines. The complexity of the concept may not be simplified as it is absolutely essential for full understanding of its nature. In order to gain better orientation in the concept, different perspectives will be used in the description of the model, which will enable us to achieve the goal of the work and to present the main results of the work (creation of a model for Virtual Development Management System. The present paper thus describes from different perspectives the proposal of a sufficiently detailed and complex model that may be utilized both on theoretical and application level.

  2. Determining Predictor Importance in Hierarchical Linear Models Using Dominance Analysis

    Science.gov (United States)

    Luo, Wen; Azen, Razia

    2013-01-01

    Dominance analysis (DA) is a method used to evaluate the relative importance of predictors that was originally proposed for linear regression models. This article proposes an extension of DA that allows researchers to determine the relative importance of predictors in hierarchical linear models (HLM). Commonly used measures of model adequacy in…

  3. On the origin of constrained superfields

    Energy Technology Data Exchange (ETDEWEB)

    Dall’Agata, G. [Dipartimento di Fisica “Galileo Galilei”, Università di Padova,Via Marzolo 8, 35131 Padova (Italy); INFN, Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy); Dudas, E. [Centre de Physique Théorique, École Polytechnique, CNRS, Université Paris-Saclay,F-91128 Palaiseau (France); Farakos, F. [Dipartimento di Fisica “Galileo Galilei”, Università di Padova,Via Marzolo 8, 35131 Padova (Italy); INFN, Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy)

    2016-05-06

    In this work we analyze constrained superfields in supersymmetry and supergravity. We propose a constraint that, in combination with the constrained goldstino multiplet, consistently removes any selected component from a generic superfield. We also describe its origin, providing the operators whose equations of motion lead to the decoupling of such components. We illustrate our proposal by means of various examples and show how known constraints can be reproduced by our method.

  4. How to model mutually exclusive events based on independent causal pathways in Bayesian network models

    OpenAIRE

    Fenton, N.; Neil, M.; Lagnado, D.; Marsh, W.; Yet, B.; Constantinou, A.

    2016-01-01

    We show that existing Bayesian network (BN) modelling techniques cannot capture the correct intuitive reasoning in the important case when a set of mutually exclusive events need to be modelled as separate nodes instead of states of a single node. A previously proposed ‘solution’, which introduces a simple constraint node that enforces mutual exclusivity, fails to preserve the prior probabilities of the events, while other proposed solutions involve major changes to the original model. We pro...

  5. Evaluation of a proposed optimization method for discrete-event simulation models

    Directory of Open Access Journals (Sweden)

    Alexandre Ferreira de Pinho

    2012-12-01

    Full Text Available Optimization methods combined with computer-based simulation have been utilized in a wide range of manufacturing applications. However, in terms of current technology, these methods exhibit low performance levels which are only able to manipulate a single decision variable at a time. Thus, the objective of this article is to evaluate a proposed optimization method for discrete-event simulation models based on genetic algorithms which exhibits more efficiency in relation to computational time when compared to software packages on the market. It should be emphasized that the variable's response quality will not be altered; that is, the proposed method will maintain the solutions' effectiveness. Thus, the study draws a comparison between the proposed method and that of a simulation instrument already available on the market and has been examined in academic literature. Conclusions are presented, confirming the proposed optimization method's efficiency.

  6. B220 analysis with the local lymph node assay: proposal for a more flexible prediction model.

    Science.gov (United States)

    Betts, Catherine J; Dearman, Rebecca J; Kimber, Ian; Ryan, Cindy A; Gerberick, G Frank; Lalko, Jon; Api, Anne Marie

    2007-01-01

    The mouse local lymph node assay (LLNA) has been developed and validated for the identification of chemicals that have the potential to induce skin sensitisation. In common with other predictive test methods the accuracy of the LLNA is not absolute and experience has revealed that a few chemicals, including for instance a minority of skin irritants, may elicit false-positive reactions in the assay. To improve further the performance of the LLNA, and to eliminate or reduce false-positives, there has been interest in an adjunct method in which the ability of chemicals to cause increases in the frequency of B220(+) lymphocytes in skin-draining lymph nodes is measured. Previous studies suggest that the use of B220 analyses aligned with the standard LLNA may serve to distinguish further between contact allergens and skin irritants. In the original predictive model, chemicals were regarded as being skin sensitisers if they were able to induce a 1.25-fold or greater increase in the percentage of B220(+) cells within lymph nodes compared with concurrent vehicle controls. Although this first prediction model has proven useful, in the light of more recent experience, and specifically as a consequence of some variability observed in the frequency of B220(+) lymphocytes in nodes taken from vehicle control-treated animals, it is timely now to reconsider and refine the model. As a result a new prediction model is proposed in which reliance on the use of absolute thresholds is reduced, and in which small changes in control values can be better accommodated. (c) 2007 John Wiley & Sons, Ltd.

  7. [Determination of wine original regions using information fusion of NIR and MIR spectroscopy].

    Science.gov (United States)

    Xiang, Ling-Li; Li, Meng-Hua; Li, Jing-Mingz; Li, Jun-Hui; Zhang, Lu-Da; Zhao, Long-Lian

    2014-10-01

    Geographical origins of wine grapes are significant factors affecting wine quality and wine prices. Tasters' evaluation is a good method but has some limitations. It is important to discriminate different wine original regions quickly and accurately. The present paper proposed a method to determine wine original regions based on Bayesian information fusion that fused near-infrared (NIR) transmission spectra information and mid-infrared (MIR) ATR spectra information of wines. This method improved the determination results by expanding the sources of analysis information. NIR spectra and MIR spectra of 153 wine samples from four different regions of grape growing were collected by near-infrared and mid-infrared Fourier transform spe trometer separately. These four different regions are Huailai, Yantai, Gansu and Changli, which areall typical geographical originals for Chinese wines. NIR and MIR discriminant models for wine regions were established using partial least squares discriminant analysis (PLS-DA) based on NIR spectra and MIR spectra separately. In PLS-DA, the regions of wine samples are presented in group of binary code. There are four wine regions in this paper, thereby using four nodes standing for categorical variables. The output nodes values for each sample in NIR and MIR models were normalized first. These values stand for the probabilities of each sample belonging to each category. They seemed as the input to the Bayesian discriminant formula as a priori probability value. The probabilities were substituteed into the Bayesian formula to get posterior probabilities, by which we can judge the new class characteristics of these samples. Considering the stability of PLS-DA models, all the wine samples were divided into calibration sets and validation sets randomly for ten times. The results of NIR and MIR discriminant models of four wine regions were as follows: the average accuracy rates of calibration sets were 78.21% (NIR) and 82.57% (MIR), and the

  8. Modeling of Possible Conditions for Origin of First Organic Forms in hot Mineral Water

    OpenAIRE

    Ignat Ignatov; Oleg Mosin

    2014-01-01

    The composition of water, its temperature and pH value was analyzed in experiments with modelling of primary hydrosphere and possible conditions for origin of first organic forms in hot mineral water. For this aim the authors performed experiments with hot mineral and seawater from Bulgaria by IR-spectrometry (DNES-method). As model systems were used cactus juice of Echinopsis pachanoi and Mediterranean jellyfish Cotylorhiza tuberculata. It was considered the reactions of condensation and deh...

  9. Proposed Model for Translational Research at a Teaching-Intensive College of Pharmacy.

    Science.gov (United States)

    Ulrich, Erin; Grady, Sarah; Vonderhaar, Jacqueline; Ruplin, Andrew

    2017-08-08

    Many American colleges of pharmacy are small, private, teaching institutions. Faculty are required to maintain a research agenda, although the publication quota is less compared with their publicly funded college of pharmacy peers. Faculty at these smaller schools conduct research with very little internal or external funding. This tends to lead to smaller, less impactful research findings. Translational research is becoming popular for research faculty as it bridges theory to practice. The Knowledge-to-Action (KTA) framework presents the steps to conduct translational research. To apply and determine if the KTA framework would be able to produce practice-impactful research at an institution that does not depend on grant funding as part of faculty research agendas. An interdisciplinary team was formed with providers at the clinical faculty's practice site. As the team moved through the KTA steps, authors documented the roles of each team member. It was clear that many different types of teams were formed throughout the KTA process. These teams were then categorized according to the Interdisciplinary Teamwork System. The final result is a proposed model of types of teams and required member roles that are necessary within each KTA step for faculty to conduct practice-impactful research at a small, private, teaching institution without substantial grant funding awards. Applying the KTA framework, two impactful original research manuscripts were developed over two academic years. Furthermore, the practitioners at the clinical faculty member's site were very pleased with the ease of conducting research, as they were never required to take a lead role. In addition, both faculty members alternated lead and support role allowing for a decreased burden of workload while producing theory-driven research. The KTA framework can create a model for translational research and may be particularly beneficial to small teaching institutions to conduct impactful research. Copyright

  10. Towards an integrative framework of brand country of origin recognition determinants : a cross-classified hierarchical model

    OpenAIRE

    Cerviño, Julio

    2011-01-01

    To propose a framework integrating the types and levels of the determinants of brand CO recognition and to provide evidence on Internet users’ brand CO recognition rates using a sample of multi-regional and global brands from a variety of product categories and countries. We integrate 'level-1' consumer and brand characteristics and 'level-2' product category and country effects in a single framework. Data obtained through an original on-line survey hosted by Yahoo provide the basis ...

  11. ON THE DYNAMICS AND ORIGIN OF HAUMEA'S MOONS

    Energy Technology Data Exchange (ETDEWEB)

    Ćuk, Matija [Carl Sagan Center, SETI Institute, 189 North Bernardo Avenue, Mountain View, CA 94043 (United States); Ragozzine, Darin [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Nesvorný, David, E-mail: mcuk@seti.org [Southwest Research Institute, Boulder, CO 80302 (United States)

    2013-10-01

    The dwarf planet Haumea has two large satellites, Namaka and Hi'iaka, which orbit at relatively large separations. Both moons have significant eccentricities and inclinations in a pattern that is consistent with a past orbital resonance. Based on our analysis, we find that the present system is not consistent with satellite formation close to the primary and tidal evolution through mean-motion resonances. We propose that Namaka experienced only limited tidal evolution, leading to the mutual 8:3 mean-motion resonance which redistributed eccentricities and inclinations between the moons. This scenario requires that the original orbit of Hi'iaka was mildly eccentric; we propose that this eccentricity was either primordial or acquired through encounters with other trans-Neptunian objects. Both dynamical stability and our preferred tidal evolution model imply that the moons' masses are only about one-half of previously estimated values, suggesting high albedos and low densities. Because the present orbits of the moons strongly suggest formation from a flat disk close to their present locations, we conclude that Hi'iaka and Namaka may be second-generation moons, formed after the breakup of a larger past moon, previously proposed as the parent body of the Haumea family. We derive plausible parameters of that moon, consistent with the current models of Haumea's formation. An interesting implication of this hypothesis is that Hi'iaka and Namaka may orbit retrograde with respect to Haumea's spin. Retrograde orbits of Haumea's moons would be in full agreement with available observations and our dynamical analysis, and could provide a unique confirmation of the ''disrupted satellite'' scenario for the origin of the family.

  12. Proposed Model of Information Behaviour in Crisis: The Case of Hurricane Sandy

    Science.gov (United States)

    Lopatovska, Irene; Smiley, Bobby

    2013-01-01

    Introduction: The paper proposes a model of information behaviour in crisis. No previous model has attempted to integrate information resources, information behaviour and needs of the storm-affected communities within the temporal stages of a natural disaster. Method: The study was designed as autoethnography. The data were collected through a…

  13. The Proposed Model of Collaborative Virtual Learning Environment for Introductory Programming Course

    Science.gov (United States)

    Othman, Mahfudzah; Othman, Muhaini

    2012-01-01

    This paper discusses the proposed model of the collaborative virtual learning system for the introductory computer programming course which uses one of the collaborative learning techniques known as the "Think-Pair-Share". The main objective of this study is to design a model for an online learning system that facilitates the…

  14. Origin and evolution of Sariñena Lake (central Ebro Basin): A piping-based model

    Science.gov (United States)

    Castañeda, Carmen; Javier Gracia, F.; Rodríguez-Ochoa, Rafael; Zarroca, Mario; Roqué, Carles; Linares, Rogelio; Desir, Gloria

    2017-08-01

    The origin and nature of the numerous lakes in the central Ebro Basin have been interpreted according to the prevailing arid or semiarid conditions, the easily-eroded materials and the solubility of the gypsum- and/or carbonate-rich Tertiary/Cenozoic substratum, involving important dissolution (karstic) and/or aeolian deflation. However, the origin of Sariñena Lake, the largest in the central Ebro Basin, remains unknown since the typical lake-generating processes in the region are not applicable. This work provides significant clues to the genesis and evolution of Sariñena Lake in a regional context. The combination of geomorphological mapping and high resolution LiDAR data together with sedimentological observations, the characterisation of soils and sediments around the lake, and the application of high-resolution geophysical techniques suggest that piping is the major genetic process driving the evolution of the Sariñena depression and lake. Field evidence demonstrates that piping is, at present, the most important erosive process in the region, generating significant collapse and surface lowering. Sariñena Lake is located within a deep endorheic depression excavated from Na-rich Tertiary materials. This work hypothesises that once an early, fluvially-originated palustrine area had developed, the progressive lowering of the regional water table linked to regional fluvial incision favoured the establishment of a hydrological gradient high enough to trigger piping processes within the claystones and siltstones underlying the original palustrine area. The Quaternary evolution of the Sariñena lacustrine basin was then controlled by successive water table fluctuations, linked to different phases of incision and alluvial deposition in the surrounding fluvial systems. All the evidence supporting a piping-related origin for this lake, together with examples of lakes generated by similar processes in different contexts, is used to propose a new genetic type of

  15. Development-based Trust: Proposing and Validating a New Trust Measurement Model for Buyer-Seller Relationships

    Directory of Open Access Journals (Sweden)

    José Mauro da Costa Hernandez

    2010-04-01

    Full Text Available This study proposes and validates a trust measurement model for buyer-seller relationships. Baptized as development-based trust, the model encompasses three dimensions of trust: calculus-based, knowledge-based and identification-based. In addition to recognizing that trust is a multidimensional construct, the model also assumes that trust can evolve to take on a different character depending on the stage of the relationship. In order to test the proposed model and compare it to the characteristic-based trust measurement model, the measure most frequently used in the buyer-seller relationship literature, data were collected from 238 clients of an IT product wholesaler. The results show that the scales are valid and reliable and the proposed development-based trust measurement model is superior to the characteristic-based trust measurement model in terms of its ability to explain certain variables of interest in buyer-seller relationships (long-term relationship orientation, information sharing, behavioral loyalty and future intentions. Implications for practice, limitations and suggestions for future studies are discussed.

  16. A model of accumulation of radionuclides in biosphere originating from groundwater contamination

    International Nuclear Information System (INIS)

    Gaerdenaes, Annemieke; Jansson, Per-Erik; Karlberg, Louise

    2006-03-01

    The objective of this study is to introduce a module in CoupModel describing the transport and accumulation in the biosphere of a radionuclide originating from a ground water contamination. Two model approaches describing the plant uptake of a radionuclide were included, namely passive and active uptake. Passive uptake means in this study that the root uptake rate of a radionuclide is governed by water uptake. Normal mechanism for the passive water uptake is the convective flux of water from the soil to the plant. An example of element taken up passively is Ca. Active plant uptake is in this model defined as the root uptake rate of a radionuclide that is governed by carbon assimilation i.e. photosynthesis and plant growth. The actively taken up element can for example be an element essential to plant, but not available in high enough concentration by passive uptake alone, like the major nutrients N and P or an element that very well resembles a plant nutrient, like Cs resembles K. Active uptake of trace element may occur alone or in addition to passive uptake. Normal mechanism for the active uptake is molecular diffusion from the soil solution to the roots or via any other organism living in symbiosis with the roots like the mycorrhiza. Also a model approach describing adsorption was introduced. CoupModel dynamically couples and simulates the flows of water, heat, carbon and nitrogen in the soil/plant/atmosphere system. Any number of plants may be defined and are divided into roots, leaves, stem and grain. The soil is considered in one vertical profile that may be represented into a maximum of 100 layers. The model is the windows-successor and integrated version of the DOS-models SOIL and SOILN, which have been widely used on different ecosystems and climate regions during 25 years time period. To this soil/plant/atmosphere model were introduced a module describing accumulation of a radionuclide in the biosphere originating from groundwater contamination. The

  17. A model of accumulation of radionuclides in biosphere originating from groundwater contamination

    Energy Technology Data Exchange (ETDEWEB)

    Gaerdenaes, Annemieke [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Soil Sciences; Jansson, Per-Erik; Karlberg, Louise [Royal Inst. of Technology, Stockholm (Sweden). Dept. Land and Water Resources

    2006-03-15

    The objective of this study is to introduce a module in CoupModel describing the transport and accumulation in the biosphere of a radionuclide originating from a ground water contamination. Two model approaches describing the plant uptake of a radionuclide were included, namely passive and active uptake. Passive uptake means in this study that the root uptake rate of a radionuclide is governed by water uptake. Normal mechanism for the passive water uptake is the convective flux of water from the soil to the plant. An example of element taken up passively is Ca. Active plant uptake is in this model defined as the root uptake rate of a radionuclide that is governed by carbon assimilation i.e. photosynthesis and plant growth. The actively taken up element can for example be an element essential to plant, but not available in high enough concentration by passive uptake alone, like the major nutrients N and P or an element that very well resembles a plant nutrient, like Cs resembles K. Active uptake of trace element may occur alone or in addition to passive uptake. Normal mechanism for the active uptake is molecular diffusion from the soil solution to the roots or via any other organism living in symbiosis with the roots like the mycorrhiza. Also a model approach describing adsorption was introduced. CoupModel dynamically couples and simulates the flows of water, heat, carbon and nitrogen in the soil/plant/atmosphere system. Any number of plants may be defined and are divided into roots, leaves, stem and grain. The soil is considered in one vertical profile that may be represented into a maximum of 100 layers. The model is the windows-successor and integrated version of the DOS-models SOIL and SOILN, which have been widely used on different ecosystems and climate regions during 25 years time period. To this soil/plant/atmosphere model were introduced a module describing accumulation of a radionuclide in the biosphere originating from groundwater contamination. The

  18. DEVELOPING AND PROPOSING A CONCEPTUAL MODEL OF THE FLOW EXPERIENCE DURING ONLINE INFORMATION SEARCH

    Directory of Open Access Journals (Sweden)

    Lazoc Alina

    2012-07-01

    Full Text Available Information search is an essential part of the consumer`s decision making process. The online medium offers new opportunities and challenges for information search activities (in and outside the marketing context. We are interested in the way human information experiences and behaviors are affected by this. Very often online games and social web activities are perceived as challenging, engaging and enjoyable, while online information search is far below this evaluation. Our research proposal implies that using the online medium for information search may provoke enjoyable experiences through the flow state, which may in turn positively influence an individual`s exploratory information behavior and encourage his/her pro-active market behavior. The present study sets out to improve the understanding of the online medium`s impact on human`s exploratory behavior. We hypothesize that the inclusion of the online flow experience in our research model will better explain exploratory information search behaviors. A 11-component conceptual framework is proposed to explain the manifestations of flow, its personal and technological determinants and its behavioral consequence in the context of online information search. Our research has the primary purpose to present an integrated online flow model. Its secondary objective is to stimulate extended research in the area of informational behaviors in the digital age. The paper is organized in three sections. In the first section we briefly report the analysis results of the most relevant online flow theory literature and, drawing on it, we are trying to identify variables and relationships among these. In the second part we propose a research model and use prior flow models to specify a range of testable hypothesis. Drawing on the conceptual model developed, the last section of our study presents the final conclusions and proposes further steps in evaluating the model`s validity. Future research directions

  19. The Inertia Reaction Force and Its Vacuum Origin

    Science.gov (United States)

    Rueda, Alfonso; Haisch, Bernard

    By means of a covariant approach we show that there must be a contribution to the inertial mass and to the inertial reaction force on an accelerated massive object by the zero-point electromagnetic field. This development does not require any detailed model of the accelerated object other than the knowledge that it interacts electromagnetically. It is shown that inertia can indeed be construed as an opposition of the vacuum fields to any change to the uniform state of motion of an object. Interesting insights originating from this result are discussed. It is argued why the proposed existence of a Higgs field in no way contradicts or is at odds with the above statements. The Higgs field is responsible for assigning mass to elementary particles. It is argued that still the underlying reason for the opposition to acceleration that massive objects present requires an explanation. The explanation proposed here fulfills that requirement.

  20. A Data-origin Authentication Protocol Based on ONOS Cluster

    Directory of Open Access Journals (Sweden)

    Qin Hua

    2016-01-01

    Full Text Available This paper is aim to propose a data-origin authentication protocol based on ONOS cluster. ONOS is a SDN controller which can work under a distributed environment. However, the security of an ONOS cluster is seldom considered, and the communication in an ONOS cluster may suffer from lots of security threats. In this paper, we used a two-tier self-renewable hash chain for identity authentication and data-origin authentication. We analyse the security and overhead of our proposal and made a comparison with current security measure. It showed that with the help of our proposal, communication in an ONOS cluster could be protected from identity forging, replay attacks, data tampering, MITM attacks and repudiation, also the computational overhead would decrease apparently.

  1. Reflective Practice: Origins and Interpretations

    Science.gov (United States)

    Reynolds, Michael

    2011-01-01

    The idea of reflection is central to the theory and practice of learning--especially learning which is grounded in past or current experience. This paper proposes a working definition of reflection and reviews its origins and recent developments. The author also provides an account of "critical reflection", including its rationale and…

  2. A proposal concerning the origin of life on the planet earth

    Science.gov (United States)

    Woese, C. R.

    1979-01-01

    It is proposed that, contrary to the widely accepted Oparin thesis, life on earth arose not in the oceans but in the earth's atmosphere. Difficulties of the Oparin thesis relating to the nonbiological nature of prebiotic evolution are discussed, and autotrophic, photosynthetic cells are proposed as the first living organisms to emerge, thus avoiding these difficulties. Recent developments in the geology of the earth at the time of the emergence of life are interpreted as requiring the absence of liquid surface water, with water partitioned between a molten crust and a dense, CO2-rich atmosphere, similar to the present state of Venus. Biochemistry in such an atmosphere would be primarily membrane chemistry on the interfaces of atmospheric salt water droplets, proceeding at normal temperatures without the absorption of electrical discharges or UV light. Areas not sufficiently accounted for by this scenario include the development of genetic organization and the breaking of the runaway greenhouse condition assumed.

  3. Holistic self-management education and support: a proposed public health model for improving women's health in Zimbabwe.

    Science.gov (United States)

    Kanchense, Jane Handina Murigwa

    2006-08-01

    The primary health care model of public health has been implemented in many countries around the globe since the Declaration of Alma Ata in 1978, without pilot testing the primary health care model. Therefore, many public health researchers have sought methods of improving primary health care by creating evidence-based models. Many of these researchers recognize the role of behavioral models in public health. These offshoots of primary health care include the ecological, care, central human capabilities, and the SPECIES models. Holistic self-management education and support is a capacity-building philosophy that ensures active involvement of consumers of health care in the planning and implementation and evaluation of health care services. It helps consumers of health care to achieve the desired improved quality of health and life in managing and sustaining their health at the grassroots level. The care model addresses disease management ideals of the in the original primary health care model. The SPECIES model addresses those aspects of the primary health care model that include the cultural and social factors, as well as individual health education and support in the original primary health care model. The ecological model offers an improvement of the socioeconomic ideal in the original primary health care model. Improving the health of individuals will prevent illness, thereby reducing health care costs and lessening the current strain on an overburdened health care system in Zimbabwe. Holistic self-management education and support links health care delivery systems with social processes. It is a best practices model that could better serve Zimbabwean girls and women by contributing positively to the national challenges in health care, thereby meeting the Zimbabwean primary health care and safe motherhood goals. It is here recommended that holistic self-management education and support must be pilot tested before being adopted as the most appropriate model for

  4. Osteosarcoma: Cells-of-Origin, Cancer Stem Cells, and Targeted Therapies

    Directory of Open Access Journals (Sweden)

    Ander Abarrategi

    2016-01-01

    Full Text Available Osteosarcoma (OS is the most common type of primary solid tumor that develops in bone. Although standard chemotherapy has significantly improved long-term survival over the past few decades, the outcome for those patients with metastatic or recurrent OS remains dismally poor and, therefore, novel agents and treatment regimens are urgently required. A hypothesis to explain the resistance of OS to chemotherapy is the existence of drug resistant CSCs with progenitor properties that are responsible of tumor relapses and metastasis. These subpopulations of CSCs commonly emerge during tumor evolution from the cell-of-origin, which are the normal cells that acquire the first cancer-promoting mutations to initiate tumor formation. In OS, several cell types along the osteogenic lineage have been proposed as cell-of-origin. Both the cell-of-origin and their derived CSC subpopulations are highly influenced by environmental and epigenetic factors and, therefore, targeting the OS-CSC environment and niche is the rationale for many recently postulated therapies. Likewise, some strategies for targeting CSC-associated signaling pathways have already been tested in both preclinical and clinical settings. This review recapitulates current OS cell-of-origin models, the properties of the OS-CSC and its niche, and potential new therapies able to target OS-CSCs.

  5. Original analytic solution of a half-bridge modelled as a statically indeterminate system

    Science.gov (United States)

    Oanta, Emil M.; Panait, Cornel; Raicu, Alexandra; Barhalescu, Mihaela

    2016-12-01

    The paper presents an original computer based analytical model of a half-bridge belonging to a circular settling tank. The primary unknown is computed using the force method, the coefficients of the canonical equation being calculated using either the discretization of the bending moment diagram in trapezoids, or using the relations specific to the polygons. A second algorithm based on the method of initial parameters is also presented. Analyzing the new solution we came to the conclusion that most of the computer code developed for other model may be reused. The results are useful to evaluate the behavior of the structure and to compare with the results of the finite element models.

  6. Proposed alternatives for international plutonium storage

    International Nuclear Information System (INIS)

    de Montmollin, J.M.

    1983-01-01

    The IAEA Director General convened an Expert Group in December 1978, to study proposals for implementing some form of IPS. The Group labored for three years, developing details of a single proposed concept. In early 1982 a group of developing countries proposed a different and less-restrictive scheme, which was labeled Alternative B. In response, three other countries proposed a scheme more restrictive than the original Alternative A. The Expert Group forwarded all three alternatives to the Board of Governors, without recommendation, in its final report. In this paper the features that distinguish each of the alternatives are described

  7. The origin of ethics and social order in a society without state power.

    Science.gov (United States)

    Yamamoto, K

    1999-06-01

    How ethics and social order in a society without state power had originated and developed is one of enigmas which human beings have tried to solve for a long time. Several theories on the origin of social order have been proposed since the "Social Contract" theory of Thomas Hobbes. According to Hobbes, as a society without state power is in a condition called war, a social contract among men is the origin of social order in a society where every man is against every man. Rousseau says that when human beings reach the stage in which they live in a permanent neighborhood, a property system is introduced. Then, too much ambition and avarice of man who has possessions compel him to propose the formation of a political institution, providing social order which enables him to keep his possessions. According to Nietzsche, the principle of equilibrium, that is, an eye for an eye, a tooth for a tooth is an important concept for the oldest theory of low and morality as well as the basis of justice. The sense of superiority and nobility which a strong man brave enough to take revenge feels is the origin of the antithesis "good" and "bad". Girard says that the sacred violence wielded by the community to sacrifice a surrogate victim brings about social order in a society without state power. All the aforementioned theories seem to have failed to find out that a society without state power has its own ethics that had spontaneously developed on the pagan culture. Previously, I indicated that a society without state power or a society where state power cannot function well, such as the tribal society in northern Albania, has ethics which is based on the ancient concepts of "Guest-god", "food (commensality)" and "blood". In the present paper, I propose a new theory on the origin of ethics and social order, using the model of ethics of the Kanun.

  8. Feasibility analysis in the expansion proposal of the nuclear power plant Laguna Verde: application of real options, binomial model

    International Nuclear Information System (INIS)

    Hernandez I, S.; Ortiz C, E.; Chavez M, C.

    2011-11-01

    At the present time, is an unquestionable fact that the nuclear electrical energy is a topic of vital importance, no more because eliminates the dependence of the hydrocarbons and is friendly with the environment, but because is also a sure and reliable energy source, and represents a viable alternative before the claims in the growing demand of electricity in Mexico. Before this panorama, was intended several scenarios to elevate the capacity of electric generation of nuclear origin with a variable participation. One of the contemplated scenarios is represented by the expansion project of the nuclear power plant Laguna Verde through the addition of a third reactor that serves as detonator of an integral program that proposes the installation of more nuclear reactors in the country. Before this possible scenario, the Federal Commission of Electricity like responsible organism of supplying energy to the population should have tools that offer it the flexibility to be adapted to the possible changes that will be presented along the project and also gives a value to the risk to future. The methodology denominated Real Options, Binomial model was proposed as an evaluation tool that allows to quantify the value of the expansion proposal, demonstrating the feasibility of the project through a periodic visualization of their evolution, all with the objective of supplying a financial analysis that serves as base and justification before the evident apogee of the nuclear energy that will be presented in future years. (Author)

  9. A Framework Proposal For Choosing A New Business Implementation Model In Henkel

    OpenAIRE

    Li, Tsz Wan

    2015-01-01

    Henkel's New Business team is a corporate venturing unit that explores corporate entrepreneurial activities on behalf of Henkel Adhesives Technologies. The new business ideas are implemented through one of these models: incubator, venturing or innovation ecosystem. In current practice, there is no systematic framework in place to choose the implementation model. The goal of the thesis is to propose a framework for choosing the most appropriate model for implementation of a new business idea i...

  10. BioQ: tracing experimental origins in public genomic databases using a novel data provenance model.

    Science.gov (United States)

    Saccone, Scott F; Quan, Jiaxi; Jones, Peter L

    2012-04-15

    Public genomic databases, which are often used to guide genetic studies of human disease, are now being applied to genomic medicine through in silico integrative genomics. These databases, however, often lack tools for systematically determining the experimental origins of the data. We introduce a new data provenance model that we have implemented in a public web application, BioQ, for assessing the reliability of the data by systematically tracing its experimental origins to the original subjects and biologics. BioQ allows investigators to both visualize data provenance as well as explore individual elements of experimental process flow using precise tools for detailed data exploration and documentation. It includes a number of human genetic variation databases such as the HapMap and 1000 Genomes projects. BioQ is freely available to the public at http://bioq.saclab.net.

  11. HIGHLY-ACCURATE MODEL ORDER REDUCTION TECHNIQUE ON A DISCRETE DOMAIN

    Directory of Open Access Journals (Sweden)

    L. D. Ribeiro

    2015-09-01

    Full Text Available AbstractIn this work, we present a highly-accurate technique of model order reduction applied to staged processes. The proposed method reduces the dimension of the original system based on null values of moment-weighted sums of heat and mass balance residuals on real stages. To compute these sums of weighted residuals, a discrete form of Gauss-Lobatto quadrature was developed, allowing a high degree of accuracy in these calculations. The locations where the residuals are cancelled vary with time and operating conditions, characterizing a desirable adaptive nature of this technique. Balances related to upstream and downstream devices (such as condenser, reboiler, and feed tray of a distillation column are considered as boundary conditions of the corresponding difference-differential equations system. The chosen number of moments is the dimension of the reduced model being much lower than the dimension of the complete model and does not depend on the size of the original model. Scaling of the discrete independent variable related with the stages was crucial for the computational implementation of the proposed method, avoiding accumulation of round-off errors present even in low-degree polynomial approximations in the original discrete variable. Dynamical simulations of distillation columns were carried out to check the performance of the proposed model order reduction technique. The obtained results show the superiority of the proposed procedure in comparison with the orthogonal collocation method.

  12. Proposal for operator's mental model using the concept of multilevel flow modeling

    International Nuclear Information System (INIS)

    Yoshimura, Seiichi; Takano, Kenichi; Sasou, Kunihide

    1995-01-01

    It is necessary to analyze an operator's thinking process and a operator team's intension forming process for preventing human errors in a highly advanced huge system like a nuclear power plant. Central Research Institute of Electric Power Industry is promoting a research project to establish human error prevention countermeasures by modeling the thinking and intension forming process. The important is the future prediction and the cause identification when abnormal situations occur in a nuclear power plant. The concept of Multilevel Flow Modeling (MFM) seems to be effective as an operator's mental model which performs the future prediction and the cause identification. MFM is a concept which qualitatively describes the plant functions by energy and mass flows and also describes the plant status by breaking down the targets in a hierarchical manner which a plant should achieve. In this paper, an operator's mental model using the concept of MFM was proposed and a nuclear power plant diagnosis support system using MFM was developed. The system evaluation test by personnel who have operational experience in nuclear power plants revealed that MFM was superior in the future prediction and the cause identification to a traditional nuclear power plant status display system which used mimics and trends. MFM proved to be useful as an operator's mental model by the test. (author)

  13. Evaluating Effectiveness of Modeling Motion System Feedback in the Enhanced Hess Structural Model of the Human Operator

    Science.gov (United States)

    Zaychik, Kirill; Cardullo, Frank; George, Gary; Kelly, Lon C.

    2009-01-01

    In order to use the Hess Structural Model to predict the need for certain cueing systems, George and Cardullo significantly expanded it by adding motion feedback to the model and incorporating models of the motion system dynamics, motion cueing algorithm and a vestibular system. This paper proposes a methodology to evaluate effectiveness of these innovations by performing a comparison analysis of the model performance with and without the expanded motion feedback. The proposed methodology is composed of two stages. The first stage involves fine-tuning parameters of the original Hess structural model in order to match the actual control behavior recorded during the experiments at NASA Visual Motion Simulator (VMS) facility. The parameter tuning procedure utilizes a new automated parameter identification technique, which was developed at the Man-Machine Systems Lab at SUNY Binghamton. In the second stage of the proposed methodology, an expanded motion feedback is added to the structural model. The resulting performance of the model is then compared to that of the original one. As proposed by Hess, metrics to evaluate the performance of the models include comparison against the crossover models standards imposed on the crossover frequency and phase margin of the overall man-machine system. Preliminary results indicate the advantage of having the model of the motion system and motion cueing incorporated into the model of the human operator. It is also demonstrated that the crossover frequency and the phase margin of the expanded model are well within the limits imposed by the crossover model.

  14. Revival of the Deser-Woodard nonlocal gravity model: Comparison of the original nonlocal form and a localized formulation

    Science.gov (United States)

    Park, Sohyun

    2018-02-01

    We examine the origin of two opposite results for the growth of perturbations in the Deser-Woodard (DW) nonlocal gravity model. One group previously analyzed the model in its original nonlocal form and showed that the growth of structure in the DW model is enhanced compared to general relativity (GR) and thus concluded that the model was ruled out. Recently, however, another group has reanalyzed it by localizing the model and found that the growth in their localized version is suppressed even compared to the one in GR. The question was whether the discrepancy originates from an intrinsic difference between the nonlocal and localized formulations or is due to their different implementations of the subhorizon limit. We show that the nonlocal and local formulations give the same solutions for the linear perturbations as long as the initial conditions are set the same. The different implementations of the subhorizon limit lead to different transient behaviors of some perturbation variables; however, they do not affect the growth of matter perturbations at the sub-horizon scale much. In the meantime, we also report an error in the numerical calculation code of the former group and verify that after fixing the error the nonlocal version also gives the suppressed growth. Finally, we discuss two alternative definitions of the effective gravitational constant taken by the two groups and some open problems.

  15. Face recognition based on symmetrical virtual image and original training image

    Science.gov (United States)

    Ke, Jingcheng; Peng, Yali; Liu, Shigang; Li, Jun; Pei, Zhao

    2018-02-01

    In face representation-based classification methods, we are able to obtain high recognition rate if a face has enough available training samples. However, in practical applications, we only have limited training samples to use. In order to obtain enough training samples, many methods simultaneously use the original training samples and corresponding virtual samples to strengthen the ability of representing the test sample. One is directly using the original training samples and corresponding mirror samples to recognize the test sample. However, when the test sample is nearly symmetrical while the original training samples are not, the integration of the original training and mirror samples might not well represent the test samples. To tackle the above-mentioned problem, in this paper, we propose a novel method to obtain a kind of virtual samples which are generated by averaging the original training samples and corresponding mirror samples. Then, the original training samples and the virtual samples are integrated to recognize the test sample. Experimental results on five face databases show that the proposed method is able to partly overcome the challenges of the various poses, facial expressions and illuminations of original face image.

  16. Proposal of a pedagogical model for mathematics teacher education

    Directory of Open Access Journals (Sweden)

    Alfonso Jiménez Espinosa

    2011-01-01

    Full Text Available This research-based article reflects on mathematics teacher education, and proposes a pedagogical model for this purpose, called Gradual Research Pedagogical Model (MPGI. This model considers the central curricular elements of any academic education process: student, teacher and contents, with evaluation as transversal element for analysis and feedback. The training of future teachers is constituted by three moments, each with its specific emphasis: the first is “contextualization”, which aims at having the student understand his or her new academic role, and identify and overcome his or her academic weak points, the second is “knowledge foundation”, which offers basic education in the fields of mathematics and pedagogy, as well as sensibilization towards social issues, opening up the student’s possibilities as leader and agent of change, and lastly, “knowledge immersion”, which is centered on research and the identification and study of topics and problems of the mathematical discipline as well as the pedagogical field.

  17. Kalman Filtered Bio Heat Transfer Model Based Self-adaptive Hybrid Magnetic Resonance Thermometry.

    Science.gov (United States)

    Zhang, Yuxin; Chen, Shuo; Deng, Kexin; Chen, Bingyao; Wei, Xing; Yang, Jiafei; Wang, Shi; Ying, Kui

    2017-01-01

    To develop a self-adaptive and fast thermometry method by combining the original hybrid magnetic resonance thermometry method and the bio heat transfer equation (BHTE) model. The proposed Kalman filtered Bio Heat Transfer Model Based Self-adaptive Hybrid Magnetic Resonance Thermometry, abbreviated as KalBHT hybrid method, introduced the BHTE model to synthesize a window on the regularization term of the hybrid algorithm, which leads to a self-adaptive regularization both spatially and temporally with change of temperature. Further, to decrease the sensitivity to accuracy of the BHTE model, Kalman filter is utilized to update the window at each iteration time. To investigate the effect of the proposed model, computer heating simulation, phantom microwave heating experiment and dynamic in-vivo model validation of liver and thoracic tumor were conducted in this study. The heating simulation indicates that the KalBHT hybrid algorithm achieves more accurate results without adjusting λ to a proper value in comparison to the hybrid algorithm. The results of the phantom heating experiment illustrate that the proposed model is able to follow temperature changes in the presence of motion and the temperature estimated also shows less noise in the background and surrounding the hot spot. The dynamic in-vivo model validation with heating simulation demonstrates that the proposed model has a higher convergence rate, more robustness to susceptibility problem surrounding the hot spot and more accuracy of temperature estimation. In the healthy liver experiment with heating simulation, the RMSE of the hot spot of the proposed model is reduced to about 50% compared to the RMSE of the original hybrid model and the convergence time becomes only about one fifth of the hybrid model. The proposed model is able to improve the accuracy of the original hybrid algorithm and accelerate the convergence rate of MR temperature estimation.

  18. Assessment of nutritional status in the elderly: a proposed function-driven model.

    Science.gov (United States)

    Engelheart, Stina; Brummer, Robert

    2018-01-01

    There is no accepted or standardized definition of 'malnutrition'. Hence, there is also no definition of what constitutes an adequate nutritional status. In elderly people, assessment of nutritional status is complex and is complicated by multi-morbidity and disabilities combined with nutrition-related problems, such as dysphagia, decreased appetite, fatigue, and muscle weakness. We propose a nutritional status model that presents nutritional status from a comprehensive functional perspective. This model visualizes the complexity of the nutritional status in elderly people. The presented model could be interpreted as the nutritional status is conditional to a person's optimal function or situation. Another way of looking at it might be that a person's nutritional status affects his or her optimal situation. The proposed model includes four domains: (1) physical function and capacity; (2) health and somatic disorders; (3) food and nutrition; and (4) cognitive, affective, and sensory function. Each domain has a major impact on nutritional status, which in turn has a major impact on the outcome of each domain. Nutritional status is a multifaceted concept and there exist several knowledge gaps in the diagnosis, prevention, and optimization of treatment of inadequate nutritional status in elderly people. The nutritional status model may be useful in nutritional assessment research, as well as in the clinical setting.

  19. A proposal on alternative sampling-based modeling method of spherical particles in stochastic media for Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Song Hyun; Lee, Jae Yong; KIm, Do Hyun; Kim, Jong Kyung [Dept. of Nuclear Engineering, Hanyang University, Seoul (Korea, Republic of); Noh, Jae Man [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-08-15

    Chord length sampling method in Monte Carlo simulations is a method used to model spherical particles with random sampling technique in a stochastic media. It has received attention due to the high calculation efficiency as well as user convenience; however, a technical issue regarding boundary effect has been noted. In this study, after analyzing the distribution characteristics of spherical particles using an explicit method, an alternative chord length sampling method is proposed. In addition, for modeling in finite media, a correction method of the boundary effect is proposed. Using the proposed method, sample probability distributions and relative errors were estimated and compared with those calculated by the explicit method. The results show that the reconstruction ability and modeling accuracy of the particle probability distribution with the proposed method were considerably high. Also, from the local packing fraction results, the proposed method can successfully solve the boundary effect problem. It is expected that the proposed method can contribute to the increasing of the modeling accuracy in stochastic media.

  20. A proposal on alternative sampling-based modeling method of spherical particles in stochastic media for Monte Carlo simulation

    International Nuclear Information System (INIS)

    Kim, Song Hyun; Lee, Jae Yong; KIm, Do Hyun; Kim, Jong Kyung; Noh, Jae Man

    2015-01-01

    Chord length sampling method in Monte Carlo simulations is a method used to model spherical particles with random sampling technique in a stochastic media. It has received attention due to the high calculation efficiency as well as user convenience; however, a technical issue regarding boundary effect has been noted. In this study, after analyzing the distribution characteristics of spherical particles using an explicit method, an alternative chord length sampling method is proposed. In addition, for modeling in finite media, a correction method of the boundary effect is proposed. Using the proposed method, sample probability distributions and relative errors were estimated and compared with those calculated by the explicit method. The results show that the reconstruction ability and modeling accuracy of the particle probability distribution with the proposed method were considerably high. Also, from the local packing fraction results, the proposed method can successfully solve the boundary effect problem. It is expected that the proposed method can contribute to the increasing of the modeling accuracy in stochastic media

  1. A model for the origin and mechanisms of CP violation

    International Nuclear Information System (INIS)

    Wu, Y.

    1995-01-01

    In this talk I will show that the two-Higgs doublet model with vacuum CP violation and approximate global U(1) family symmetries may provide one of the simplest and attractive models for understanding the origin and mechanisms of CP violation. It is shown that the mechanism of spontaneous symmetry breaking provides not only a mechanism for generating masses of the bosons and fermions, but also a mechanism for creating CP-phases of the bosons and fermions, so that CP violation occurs, after spontaneous symmetry breaking, in all possible ways from a single CP phase of the vacuum and is generally classified into four types of CP-violating mechanism. A new type of CP-violating mechanism in the charged Higgs boson interactions of the fermions is emphasized and can provide a consistent description for both established and reported CP-, P-, and T-violating phenomena. Of particular importance is the new source of CP violation for charged Higgs boson interactions that lead to the value of ε'/ε as large as 10 -3 independent of the CKM phase. copyright 1995 American Institute of Physics

  2. ORIGIN: metal creation and evolution from the cosmic dawn

    NARCIS (Netherlands)

    den Herder, J.W.; Piro, L.; Ohashi, T.; Kouveliotou, C.; Hartmann, D.H.; Kaastra, J.S.; Amati, L.; Andersen, M.I.; Arnaud, M.; Atteia, J.-L.; Bandler, S.; Barbera, M.; Barcons, X.; Barthelmy, S.; Basa, S.; Basso, S.; de Boer, M.; Branchini, E.; Branduardi-Raymont, G.; Borgani, S.; Boyarsky, A.; Brunetti, G.; Budtz-Jorgensen, C.; Burrows, D.; Butler, N.; Campana, S.; Caroli, E.; Ceballos, M.; Christensen, F.; Churazov, E.; Comastri, A.; Colasanti, L.; Cole, R.; Content, R.; Corsi, A.; Costantini, E.; Conconi, P.; Cusumano, G.; de Plaa, J.; De Rosa, A.; Del Santo, M.; Di Cosimo, S.; De Pasquale, M.; Doriese, R.; Ettori, S.; Evans, P.; Ezoe, Y.; Ferrari, L.; Finger, H.; Figueroa-Feliciano, T.; Friedrich, P.; Fujimoto, R.; Furuzawa, A.; Fynbo, J.; Gatti, F.; Galeazzi, M.; Gehrels, N.; Gendre, B.; Ghirlanda, G.; Ghisellini, G.; Gilfanov, M.; Giommi, P.; Girardi, M.; Grindlay, J.; Cocchi, M.; Godet, O.; Guedel, M.; Haardt, F.; Hartog, R.; Hepburn, I.; Hermsen, W.; Hjorth, J.; Hoekstra, H.; Holland, A.; Hornstrup, A.; van der Horst, A.; Hoshino, A.; in 't Zand, J.; Irwin, K.; Ishisaki, Y.; Jonker, P.; Kitayama, T.; Kawahara, H.; Kawai, N.; Kelley, R.; Kilbourne, C.; de Korte, P.; Kusenko, A.; Kuvvetli, I.; Labanti, M.; Macculi, C.; Maiolino, R.; Mas Hesse, M.; Matsushita, K.; Mazzotta, P.; McCammon, D.; Méndez, M.; Mignani, R.; Mineo, T.; Mitsuda, K.; Mushotzky, R.; Molendi, S.; Moscardini, L.; Natalucci, L.; Nicastro, F.; O'Brien, P.; Osborne, J.; Paerels, F.; Page, M.; Paltani, S.; Pedersen, K.; Perinati, E.; Ponman, T.; Pointecouteau, E.; Predehl, P.; Porter, S.; Rasmussen, A.; Rauw, G.; Röttgering, H.; Roncarelli, M.; Rosati, P.; Quadrini, E.; Ruchayskiy, O.; Salvaterra, R.; Sasaki, S.; Sato, K.; Savaglio, S.; Schaye, J.; Sciortino, S.; Shaposhnikov, M.; Sharples, R.; Shinozaki, K.; Spiga, D.; Sunyaev, R.; Suto, Y.; Takei, Y.; Tanvir, N.; Tashiro, M.; Tamura, T.; Tawara, Y.; Troja, E.; Tsujimoto, M.; Tsuru, T.; Ubertini, P.; Ullom, J.; Ursino, E.; Verbunt, F.; van de Voort, F.; Viel, M.; Wachter, S.; Watson, D.; Weisskopf, M.; Werner, N.; White, N.; Willingale, R.; Wijers, R.; Yamasaki, N.; Yoshikawa, K.; Zane, S.

    2012-01-01

    ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z = 10,

  3. ORIGIN : Metal creation and evolution from the cosmic dawn

    NARCIS (Netherlands)

    den Herder, Jan-Willem; Piro, Luigi; Ohashi, Takaya; Kouveliotou, Chryssa; Hartmann, Dieter H.; Kaastra, Jelle S.; Amati, L.; Andersen, M. I.; Arnaud, M.; Attéia, J.-L.; Bandler, S.; Barbera, M.; Barcons, X.; Barthelmy, S.; Basa, S.; Basso, S.; Boer, M.; Branchini, E.; Branduardi-Raymont, G.; Borgani, S.; Boyarsky, A.; Brunetti, G.; Budtz-Jorgensen, C.; Burrows, D.; Butler, N.; Campana, S.; Caroli, E.; Ceballos, M.; Christensen, F.; Churazov, E.; Comastri, A.; Colasanti, L.; Cole, R.; Content, R.; Corsi, A.; Costantini, E.; Conconi, P.; Cusumano, G.; de Plaa, J.; De Rosa, A.; Del Santo, M.; Di Cosimo, S.; De Pasquale, M.; Doriese, R.; Ettori, S.; Evans, P.; Ezoe, Y.; Ferrari, L.; Finger, H.; Figueroa-Feliciano, T.; Friedrich, P.; Fujimoto, R.; Furuzawa, A.; Fynbo, J.; Gatti, F.; Galeazzi, M.; Gehrels, N.; Gendre, B.; Ghirlanda, G.; Ghisellini, G.; Gilfanov, M.; Giommi, P.; Girardi, M.; Grindlay, J.; Cocchi, M.; Godet, O.; Guedel, M.; Haardt, F.; den Hartog, R.; Hepburn, I.; Hermsen, W.; Hjorth, J.; Hoekstra, H.; Holland, A.; Hornstrup, A.; van der Horst, A.; Hoshino, A.; in't Zand, J.; Irwin, K.; Ishisaki, Y.; Jonker, P.; Kitayama, T.; Kawahara, H.; Kawai, N.; Kelley, R.; Kilbourne, C.; de Korte, P.; Kusenko, A.; Kuvvetli, I.; Labanti, M.; Macculi, C.; Maiolino, R.; Hesse, M. Mas; Matsushita, K.; Mazzotta, P.; McCammon, D.; Méndez, M.; Mignani, R.; Mineo, T.; Mitsuda, K.; Mushotzky, R.; Molendi, S.; Moscardini, L.; Natalucci, L.; Nicastro, F.; O'Brien, P.; Osborne, J.; Paerels, F.; Page, M.; Paltani, S.; Pedersen, K.; Perinati, E.; Ponman, T.; Pointecouteau, E.; Predehl, P.; Porter, S.; Rasmussen, A.; Rauw, G.; Röttgering, H.; Roncarelli, M.; Rosati, P.; Quadrini, E.; Ruchayskiy, O.; Salvaterra, R.; Sasaki, S.; Sato, K.; Savaglio, S.; Schaye, J.; Sciortino, S.; Shaposhnikov, M.; Sharples, R.; Shinozaki, K.; Spiga, D.; Sunyaev, R.; Suto, Y.; Takei, Y.; Tanvir, N.; Tashiro, M.; Tamura, T.; Tawara, Y.; Troja, E.; Tsujimoto, M.; Tsuru, T.; Ubertini, P.; Ullom, J.; Ursino, E.; Verbunt, F.; van de Voort, F.; Viel, M.; Wachter, S.; Watson, D.; Weisskopf, M.; Werner, N.; White, N.; Willingale, R.; Wijers, R.; Yamasaki, N.; Yoshikawa, K.; Zane, S.

    2012-01-01

    ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z = 10,

  4. Is Smaller Better? A Proposal to Use Bacteria For Neuroscientific Modeling

    Directory of Open Access Journals (Sweden)

    Archana Ram

    2018-02-01

    Full Text Available Bacteria are easily characterizable model organisms with an impressively complicated set of abilities. Among them is quorum sensing, a cell-cell signaling system that may have a common evolutionary origin with eukaryotic cell-cell signaling. The two systems are behaviorally similar, but quorum sensing in bacteria is more easily studied in depth than cell-cell signaling in eukaryotes. Because of this comparative ease of study, bacterial dynamics are also more suited to direct interpretation than eukaryotic dynamics, e.g., those of the neuron. Here we review literature on neuron-like qualities of bacterial colonies and biofilms, including ion-based and hormonal signaling, and a phenomenon similar to the graded action potential. This suggests that bacteria could be used to help create more accurate and detailed biological models in neuroscientific research. More speculatively, bacterial systems may be considered an analog for neurons in biologically based computational research, allowing models to better harness the tremendous ability of biological organisms to process information and make decisions.

  5. PROPOSAL OF A MODEL MANAGEMENT TO SMALL DESIGN COMPANIES

    Directory of Open Access Journals (Sweden)

    Otávio José de OLIVEIRA

    2008-11-01

    Full Text Available The main purpose of this paper is the proposition of a management model specifically developed for small building design firms, aligned with their needs and particularities. The field research was conducted with a qualitative approach through the analysis of four case studies in small building design firms acting mainly in São Paulo City. The data collection was accomplished through semi-structured interviews, direct observation and analysis of documents. The proposed model includes guidance to the management of the core processes and activities of small building design firms, such as: organizational structure; strategic planning; planning and control of design process; costs management; sales management; information systems; human resources management; services added to the design; and performance evaluation. Key-words: design firms; design process; building construction.

  6. A Proposed Analytical Model for Integrated Pick-and-Sort Systems

    Directory of Open Access Journals (Sweden)

    Recep KIZILASLAN

    2013-11-01

    Full Text Available In this study we present an analytical approach for integration of order picking and sortation operations which are the most important, labour intensive and costly activity for warehouses. Main aim is to investigate order picking and sorting efficiencies under different design issues as a function of order wave size. Integrated analytical model is proposed to estimate the optimum order picking and order sortation efficiency. The model, which has been tested by simulations with different illustrative examples, calculates the optimum wave size that solves the trade-off between picking and sorting operations and makes the order picking and sortations efficiency maximum. Our model also allow system designer to predict the order picking and sorting capacity for different system configurations. This study presents an innovative approach for integrated warehouse operations.

  7. Implications of the Deep Minimum for Slow Solar Wind Origin

    Science.gov (United States)

    Antiochos, S. K.; Mikic, Z.; Lionello, R.; Titov, V. S.; Linker, J. A.

    2009-12-01

    The origin of the slow solar wind has long been one of the most important problems in solar/heliospheric physics. Two observational constraints make this problem especially challenging. First, the slow wind has the composition of the closed-field corona, unlike the fast wind that originates on open field lines. Second, the slow wind has substantial angular extent, of order 30 degrees, which is much larger than the widths observed for streamer stalks or the widths expected theoretically for a dynamic heliospheric current sheet. We propose that the slow wind originates from an intricate network of narrow (possibly singular) open-field corridors that emanate from the polar coronal hole regions. Using topological arguments, we show that these corridors must be ubiquitous in the solar corona. The total solar eclipse in August 2008, near the lowest point of the Deep Minimum, affords an ideal opportunity to test this theory by using the ultra-high resolution Predictive Science's (PSI) eclipse model for the corona and wind. Analysis of the PSI eclipse model demonstrates that the extent and scales of the open-field corridors can account for both the angular width of the slow wind and its closed-field composition. We discuss the implications of our slow wind theory for the structure of the corona and heliosphere at the Deep Minimum and describe further observational and theoretical tests. This work has been supported by the NASA HTP, SR&T, and LWS programs.

  8. Country-of-origin effects in consumer processing of advertising claims

    NARCIS (Netherlands)

    Verlegh, P.W.J.; Steenkamp, J.B.E.M.; Meulenberg, M.T.G.

    2005-01-01

    We propose that country of origin has a dual impact on product evaluations, acting as informational cue, but also as source variable, moderating the impact of ads on product evaluations. In support, we find a direct effect of country of origin on product evaluations, and a three-way interaction

  9. On origin of radium aureoles around Triassic uranium mineralization zones in the Peribaltic Syneclize

    International Nuclear Information System (INIS)

    Szewczyk, J.

    1985-01-01

    In the second half of the seventies, the Geological Institute began search for sandstone uranium deposits in the Triassic of the Peribaltic Syneclize. Detailed analysis of both laboratory and geophysical data showed presence of radium (Ra-226) aureoles around uranium ore bodies hitherto found by drillings. The mechanism of origin of the aureoles is explained and methodological proposal of their use in further search for uranium deposits is given. Theoretical modelling showed that origin of the aureoles is mainly related to movement of deposit waters percolating through uranium ore body. The influence of shape and dimensions of radium aureole-generating ore bodies on extent of the aureoles appears subordinate. Aureoles interesting from the point of view of prospecting may originate when velocity of percolating waters falls within the range from 10 -8 to 10 -6 cm/s. 23 refs., 7 figs., 1 tab. (author)

  10. Atmospheric origins of perchlorate on Mars and in the Atacama

    Science.gov (United States)

    Catling, D. C.; Claire, M. W.; Zahnle, K. J.; Quinn, R. C.; Clark, B. C.; Hecht, M. H.; Kounaves, S.

    2010-01-01

    Isotopic studies indicate that natural perchlorate is produced on Earth in arid environments by the oxidation of chlorine species through pathways involving ozone or its photochemical products. With this analogy, we propose that the arid environment on Mars may have given rise to perchlorate through the action of atmospheric oxidants. A variety of hypothetical pathways can be proposed including photochemical reactions, electrostatic discharge, and gas-solid reactions. Because perchlorate-rich deposits in the Atacama desert are closest in abundance to perchlorate measured at NASA's Phoenix Lander site, we made a preliminary study of the means to produce Atacama perchlorate to help shed light on the origin of Martian perchlorate. We investigated gas phase pathways using a 1-D photochemical model. We found that perchlorate can be produced in sufficient quantities to explain the abundance of perchlorate in the Atacama from a proposed gas phase oxidation of chlorine volatiles to perchloric acid. The feasibility of gas phase production for the Atacama provides justification for future investigations of gas phase photochemistry as a possible source for Martian perchlorate.

  11. Theory of the Origin, Evolution, and Nature of Life

    Directory of Open Access Journals (Sweden)

    Erik D. Andrulis

    2011-12-01

    Full Text Available Life is an inordinately complex unsolved puzzle. Despite significant theoretical progress, experimental anomalies, paradoxes, and enigmas have revealed paradigmatic limitations. Thus, the advancement of scientific understanding requires new models that resolve fundamental problems. Here, I present a theoretical framework that economically fits evidence accumulated from examinations of life. This theory is based upon a straightforward and non-mathematical core model and proposes unique yet empirically consistent explanations for major phenomena including, but not limited to, quantum gravity, phase transitions of water, why living systems are predominantly CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur, homochirality of sugars and amino acids, homeoviscous adaptation, triplet code, and DNA mutations. The theoretical framework unifies the macrocosmic and microcosmic realms, validates predicted laws of nature, and solves the puzzle of the origin and evolution of cellular life in the universe.

  12. The moon's origins

    International Nuclear Information System (INIS)

    Boss, P.; Benz, W.

    1987-01-01

    Planet formation theory is recalled. The different existing hypothesis on the moon's origins are reviewed also to see how much they are compatible with the planet formation theory. Up to now, the giant impact model seems to be the only model to satisfy all the constraints. Computerized simulation results have been presented in colloquiums and their scenarios are recalled [fr

  13. A proposed model for the transfer of environmental tritium to man and tritium metabolism in model animals

    International Nuclear Information System (INIS)

    Saito, Masahiro; Ishida, M.R.

    1987-01-01

    To evaluate the accumulated dose in human bodies due to the environmental tritium, it is of required to establish an adequate model for the tritium transfer from the environment to man and to obtain enough information on the metabolic behaviour of tritium in animal bodies using model animal system. In this report, first we describe about a proposed model for the transfer of environmental tritium to man and secondly mention briefly about the recent works on the tritium metabolism in newborn animals which have been treated as a model system of tritium intake through food chain. (author)

  14. Cell of Origin and Cancer Stem Cell Phenotype in Medulloblastomas

    Science.gov (United States)

    2017-09-01

    AWARD NUMBER: W81XWH-14-1-0115 TITLE: Cell of Origin and Cancer Stem Cell Phenotype in Medulloblastomas PRINCIPAL INVESTIGATOR: Kyuson Yun...CA130273 - Cell of Origin and Cancer Stem Cell Phenotype in Medulloblastomas 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-14-1-0115 5c. PROGRAM...hypothesis, we originally proposed to transform neural stem cells (NSCs) and neural progenitor cells (NPCs) in vivo by expressing an activated form

  15. Assessment of yellow fever epidemic risk: an original multi-criteria modeling approach.

    Directory of Open Access Journals (Sweden)

    Sylvie Briand

    Full Text Available BACKGROUND: Yellow fever (YF virtually disappeared in francophone West African countries as a result of YF mass vaccination campaigns carried out between 1940 and 1953. However, because of the failure to continue mass vaccination campaigns, a resurgence of the deadly disease in many African countries began in the early 1980s. We developed an original modeling approach to assess YF epidemic risk (vulnerability and to prioritize the populations to be vaccinated. METHODS AND FINDINGS: We chose a two-step assessment of vulnerability at district level consisting of a quantitative and qualitative assessment per country. Quantitative assessment starts with data collection on six risk factors: five risk factors associated with "exposure" to virus/vector and one with "susceptibility" of a district to YF epidemics. The multiple correspondence analysis (MCA modeling method was specifically adapted to reduce the five exposure variables to one aggregated exposure indicator. Health districts were then projected onto a two-dimensional graph to define different levels of vulnerability. Districts are presented on risk maps for qualitative analysis in consensus groups, allowing the addition of factors, such as population migrations or vector density, that could not be included in MCA. The example of rural districts in Burkina Faso show five distinct clusters of risk profiles. Based on this assessment, 32 of 55 districts comprising over 7 million people were prioritized for preventive vaccination campaigns. CONCLUSION: This assessment of yellow fever epidemic risk at the district level includes MCA modeling and consensus group modification. MCA provides a standardized way to reduce complexity. It supports an informed public health decision-making process that empowers local stakeholders through the consensus group. This original approach can be applied to any disease with documented risk factors.

  16. A powerful parent-of-origin effects test for qualitative traits on X chromosome in general pedigrees.

    Science.gov (United States)

    Zou, Qi-Lei; You, Xiao-Ping; Li, Jian-Long; Fung, Wing Kam; Zhou, Ji-Yuan

    2018-01-05

    Genomic imprinting is one of the well-known epigenetic factors causing the association between traits and genes, and has generally been examined by detecting parent-of-origin effects of alleles. A lot of methods have been proposed to test for parent-of-origin effects on autosomes based on nuclear families and general pedigrees. Although these parent-of-origin effects tests on autosomes have been available for more than 15 years, there has been no statistical test developed to test for parent-of-origin effects on X chromosome, until the parental-asymmetry test on X chromosome (XPAT) and its extensions were recently proposed. However, these methods on X chromosome are only applicable to nuclear families and thus are not suitable for general pedigrees. In this article, we propose the pedigree parental-asymmetry test on X chromosome (XPPAT) statistic to test for parent-of-origin effects in the presence of association, which can accommodate general pedigrees. When there are missing genotypes in some pedigrees, we further develop the Monte Carlo pedigree parental-asymmetry test on X chromosome (XMCPPAT) to test for parent-of-origin effects, by inferring the missing genotypes given the observed genotypes based on a Monte Carlo estimation. An extensive simulation study has been carried out to investigate the type I error rates and the powers of the proposed tests. Our simulation results show that the proposed methods control the size well under the null hypothesis of no parent-of-origin effects. Moreover, XMCPPAT substantially outperforms the existing tests and has a much higher power than XPPAT which only uses complete nuclear families (with both parents) from pedigrees. We also apply the proposed methods to analyze rheumatoid arthritis data for their practical use. The proposed XPPAT and XMCPPAT test statistics are valid and powerful in detecting parent-of-origin effects on X chromosome for qualitative traits based on general pedigrees and thus are recommended.

  17. Method of local pointed function reduction of original shape in Fourier transformation

    International Nuclear Information System (INIS)

    Dosch, H.; Slavyanov, S.Yu.

    2002-01-01

    The method for analytical reduction of the original shape in the one-dimensional Fourier transformation by the fourier image modulus is proposed. The basic concept of the method consists in the presentation of the model shape in the form of the local peak functions sum. The eigenfunctions, generated by the linear differential equations with the polynomial coefficients, are selected as the latter ones. This provides for the possibility of managing the Fourier transformation without numerical integration. This reduces the reverse task to the nonlinear regression with a small number of the evaluated parameters and to the numerical or asymptotic study on the model peak functions - the eigenfunctions of the differential tasks and their fourier images [ru

  18. Databases for highway inventories. Proposal for a new model

    Energy Technology Data Exchange (ETDEWEB)

    Perez Casan, J.A.

    2016-07-01

    Database models for highway inventories are based on classical schemes for relational databases: many related tables, in which the database designer establishes, a priori, every detail that they consider relevant for inventory management. This kind of database presents several problems. First, adapting the model and its applications when new database features appear is difficult. In addition, the different needs of different sets of road inventory users are difficult to fulfil with these schemes. For example, maintenance management services, road authorities and emergency services have different needs. In addition, this kind of database cannot be adapted to new scenarios, such as other countries and regions (that may classify roads or name certain elements differently). The problem is more complex if the language used in these scenarios is not the same as that used in the database design. In addition, technicians need a long time to learn to use the database efficiently. This paper proposes a flexible, multilanguage and multipurpose database model, which gives an effective and simple solution to the aforementioned problems. (Author)

  19. Modeling Coevolution between Language and Memory Capacity during Language Origin

    Science.gov (United States)

    Gong, Tao; Shuai, Lan

    2015-01-01

    Memory is essential to many cognitive tasks including language. Apart from empirical studies of memory effects on language acquisition and use, there lack sufficient evolutionary explorations on whether a high level of memory capacity is prerequisite for language and whether language origin could influence memory capacity. In line with evolutionary theories that natural selection refined language-related cognitive abilities, we advocated a coevolution scenario between language and memory capacity, which incorporated the genetic transmission of individual memory capacity, cultural transmission of idiolects, and natural and cultural selections on individual reproduction and language teaching. To illustrate the coevolution dynamics, we adopted a multi-agent computational model simulating the emergence of lexical items and simple syntax through iterated communications. Simulations showed that: along with the origin of a communal language, an initially-low memory capacity for acquired linguistic knowledge was boosted; and such coherent increase in linguistic understandability and memory capacities reflected a language-memory coevolution; and such coevolution stopped till memory capacities became sufficient for language communications. Statistical analyses revealed that the coevolution was realized mainly by natural selection based on individual communicative success in cultural transmissions. This work elaborated the biology-culture parallelism of language evolution, demonstrated the driving force of culturally-constituted factors for natural selection of individual cognitive abilities, and suggested that the degree difference in language-related cognitive abilities between humans and nonhuman animals could result from a coevolution with language. PMID:26544876

  20. Origins of the Non-DLVO Force between Glass Surfaces in Aqueous Solution.

    Science.gov (United States)

    Adler, Joshua J.; Rabinovich, Yakov I.; Moudgil, Brij M.

    2001-05-15

    Direct measurement of surface forces has revealed that silica surfaces seem to have a short-range repulsion that is not accounted for in classical DLVO theory. The two leading hypotheses for the origin of the non-DLVO force are (i) structuring of water at the silica interface or (ii) water penetration into the surface resulting in a gel layer. In this article, the interaction of silica surfaces will be reviewed from the perspective of the non-DLVO force origin. In an attempt to more accurately describe the behavior of silica and glass surfaces, alternative models of how surfaces with gel layers should interact are proposed. It is suggested that a lessened van der Waals attraction originating from a thin gel layer may explain both the additional stability and the coagulation behavior of silica. It is important to understand the mechanisms underlying the existence of the non-DLVO force which is likely to have a major influence on the adsorption of polymers and surfactants used to modify the silica surface for practical applications in the ceramic, mineral, and microelectronic industries. Copyright 2001 Academic Press.

  1. Cultivating Advanced Technical Writing Skills through a Graduate-Level Course on Writing Research Proposals

    Science.gov (United States)

    McCarthy, Brian D.; Dempsey, Jillian L.

    2017-01-01

    A graduate-level course focused on original research proposals is introduced to address the uneven preparation in technical writing of new chemistry graduate students. This course focuses on writing original research proposals. The general course structure features extensive group discussions, small-group activities, and regular in-class…

  2. Development and assessment of a lysophospholipid-based deep learning model to discriminate geographical origins of white rice.

    Science.gov (United States)

    Long, Nguyen Phuoc; Lim, Dong Kyu; Mo, Changyeun; Kim, Giyoung; Kwon, Sung Won

    2017-08-17

    Geographical origin determination of white rice has become the major issue of food industry. However, there is still lack of a high-throughput method for rapidly and reproducibly differentiating the geographical origins of commercial white rice. In this study, we developed a method that employed lipidomics and deep learning to discriminate white rice from Korea to China. A total of 126 white rice of 30 cultivars from different regions were utilized for the method development and validation. By using direct infusion-mass spectrometry-based targeted lipidomics, 17 lysoglycerophospholipids were simultaneously characterized within minutes per sample. Unsupervised data exploration showed a noticeable overlap of white rice between two countries. In addition, lysophosphatidylcholines (lysoPCs) were prominent in white rice from Korea while lysophosphatidylethanolamines (lysoPEs) were enriched in white rice from China. A deep learning prediction model was built using 2014 white rice and validated using two different batches of 2015 white rice. The model accurately discriminated white rice from two countries. Among 10 selected predictors, lysoPC(18:2), lysoPC(14:0), and lysoPE(16:0) were the three most important features. Random forest and gradient boosting machine models also worked well in this circumstance. In conclusion, this study provides an architecture for high-throughput classification of white rice from different geographical origins.

  3. Calculus domains modelled using an original bool algebra based on polygons

    Science.gov (United States)

    Oanta, E.; Panait, C.; Raicu, A.; Barhalescu, M.; Axinte, T.

    2016-08-01

    Analytical and numerical computer based models require analytical definitions of the calculus domains. The paper presents a method to model a calculus domain based on a bool algebra which uses solid and hollow polygons. The general calculus relations of the geometrical characteristics that are widely used in mechanical engineering are tested using several shapes of the calculus domain in order to draw conclusions regarding the most effective methods to discretize the domain. The paper also tests the results of several CAD commercial software applications which are able to compute the geometrical characteristics, being drawn interesting conclusions. The tests were also targeting the accuracy of the results vs. the number of nodes on the curved boundary of the cross section. The study required the development of an original software consisting of more than 1700 computer code lines. In comparison with other calculus methods, the discretization using convex polygons is a simpler approach. Moreover, this method doesn't lead to large numbers as the spline approximation did, in that case being required special software packages in order to offer multiple, arbitrary precision. The knowledge resulted from this study may be used to develop complex computer based models in engineering.

  4. Origin and Dispersal of Domesticated Peach Palm

    Directory of Open Access Journals (Sweden)

    Charles R. Clement

    2017-11-01

    Full Text Available Peach palm (Bactris gasipaes Kunth is a Neotropical palm domesticated by Native Americans. Its domestication resulted in a set of landraces (var. gasipaes, some with very starchy fruit used for fermentation, others with an equilibrium of starch and oil used as snacks. Which of the three wild types (var. chichagui was involved and where the domestication process began are unclear, with three hypotheses under discussion: an origin in southwestern Amazonia; or in northwestern South America; or multiple origins. We reevaluate one of the wild types, defining it as the incipient domesticate, and then evaluate these hypotheses using the Brazilian peach palm Core Collection and selected herbaria samples to: (1 model the potential distributions of wild and domesticated populations; (2 identify the probable origin of domestication with a phylogeographic analysis of chloroplast DNA sequences; and (3 determine the dispersal routes after domestication using spatial analysis of genetic diversity based on 17 nuclear microsatellite loci. The two very small-fruited wild types have distinct distributions in the northern Andes region and across southern Amazonia, both under moderately humid climates, while the incipient domesticate, partly sympatric with the southern wild type, is also found along the Equatorial Andes, in a more humid climatic envelope, more similar to that of the domesticated landraces. Two distribution models for Last Glacial Maximum conditions (CCSM4, MIROC also suggest distinct distributions for the two wild populations. The chloroplast DNA phylogeographic network confirms the area of sympatry of the incipient domesticate and the southern wild type in southwestern Amazonia as the origin of domestication. The spatial patterns of genetic diversity confirm the proposal of two dispersals, one along the Ucayali River, into western Amazonia, northwestern South America and finally Central America; the other along the Madeira River into central and

  5. Cosmic ray origin: the way ahead

    International Nuclear Information System (INIS)

    Wolfendale, A W

    2003-01-01

    Despite their discovery being 90 years ago cosmic rays are still characterised by their uncertain masses at high energy and their uncertain origin. This paper deals with the origin problem. The case is put for the majority of the particles being of galactic origin - a generally accepted result. Specific models are put forward for the galactic mechanism and that for the minority extragalactic component

  6. The fuel cell model of abiogenesis: a new approach to origin-of-life simulations.

    Science.gov (United States)

    Barge, Laura M; Kee, Terence P; Doloboff, Ivria J; Hampton, Joshua M P; Ismail, Mohammed; Pourkashanian, Mohamed; Zeytounian, John; Baum, Marc M; Moss, John A; Lin, Chung-Kuang; Kidd, Richard D; Kanik, Isik

    2014-03-01

    In this paper, we discuss how prebiotic geo-electrochemical systems can be modeled as a fuel cell and how laboratory simulations of the origin of life in general can benefit from this systems-led approach. As a specific example, the components of what we have termed the "prebiotic fuel cell" (PFC) that operates at a putative Hadean hydrothermal vent are detailed, and we used electrochemical analysis techniques and proton exchange membrane (PEM) fuel cell components to test the properties of this PFC and other geo-electrochemical systems, the results of which are reported here. The modular nature of fuel cells makes them ideal for creating geo-electrochemical reactors with which to simulate hydrothermal systems on wet rocky planets and characterize the energetic properties of the seafloor/hydrothermal interface. That electrochemical techniques should be applied to simulating the origin of life follows from the recognition of the fuel cell-like properties of prebiotic chemical systems and the earliest metabolisms. Conducting this type of laboratory simulation of the emergence of bioenergetics will not only be informative in the context of the origin of life on Earth but may help in understanding whether life might emerge in similar environments on other worlds.

  7. A long range transport model of Rn-222

    International Nuclear Information System (INIS)

    Ikebe, Y.; Kojima, S.; Shimo, M.

    1993-01-01

    In this report, we propose an analytical treatment about temporal variation of 222 Rn concentration in the atmosphere with an aim to clarify origin and transport of 222 Rn. Based on the results of numerical simulation of radon, we separate the 222 Re concentration measured at Nagoya into the following two components : (1) 222 Rn atom originated near from the measuring site, which is denoted by 'diurnal variation component'. From numerical simulation of radon, it has been shown that the measured diurnal variation can be explained by this component. (2) 222 Rn atoms originated far from the measuring site (including Chinese Continent), which is denoted by 'background component'. For this component, we propose here a one layer transport model using air mass trajectory technique. By this model we can explain the temporal variation of background component and seasonal variation of 222 Rn at Nagoya. (3 figs.)

  8. Thermodynamics of protein folding using a modified Wako-Saitô-Muñoz-Eaton model.

    Science.gov (United States)

    Tsai, Min-Yeh; Yuan, Jian-Min; Teranishi, Yoshiaki; Lin, Sheng Hsien

    2012-09-01

    Herein, we propose a modified version of the Wako-Saitô-Muñoz-Eaton (WSME) model. The proposed model introduces an empirical temperature parameter for the hypothetical structural units (i.e., foldons) in proteins to include site-dependent thermodynamic behavior. The thermodynamics for both our proposed model and the original WSME model were investigated. For a system with beta-hairpin topology, a mathematical treatment (contact-pair treatment) to facilitate the calculation of its partition function was developed. The results show that the proposed model provides better insight into the site-dependent thermodynamic behavior of the system, compared with the original WSME model. From this site-dependent point of view, the relationship between probe-dependent experimental results and model's thermodynamic predictions can be explained. The model allows for suggesting a general principle to identify foldon behavior. We also find that the backbone hydrogen bonds may play a role of structural constraints in modulating the cooperative system. Thus, our study may contribute to the understanding of the fundamental principles for the thermodynamics of protein folding.

  9. Sibling Influence on Mexican-Origin Adolescents’ Deviant and Sexual Risk Behaviors: The Role of Sibling Modeling

    Science.gov (United States)

    Whiteman, Shawn D.; Zeiders, Katharine H.; Killoren, Sarah E.; Rodriguez, Sue Annie; Updegraff, Kimberly A.

    2013-01-01

    Purpose A growing body of research indicates that siblings uniquely influence each other’s health risk behaviors during adolescence and young adulthood. Mechanisms underlying these associations, however, are largely unknown because they are rarely tested directly. The present study addressed this gap by examining the role of sibling modeling in explaining changes in Mexican-origin youths’ deviant and sexual risk behaviors over time. Methods The sample included 380 Mexican-origin siblings (older sibling age: M = 21.18, SD = 1.59; younger sibling age: M = 18.19, SD = .46) from (N = 190) families. Participants provided self-reports of their sibling relationship qualities, including modeling, as well as their engagement in deviant and sexual risk taking behaviors in two home interviews across a two-year span. Results A series of residualized regression models revealed that younger siblings’ perceptions of modeling moderated the links between older siblings’ deviant and sexual risk behaviors and younger siblings’ subsequent behaviors in those same domains. Specifically, high levels of modeling predicted stronger associations between older siblings’ earlier and younger siblings’ later risk behaviors controlling for younger siblings’ earlier behaviors as well as variables that have been used as proxies for social learning in previous research. Conclusions Social learning mechanisms, especially modeling, are salient processes through which older siblings transmit norms and expectations regarding participation in health risk behaviors. Future research should continue to explore the ways in which siblings influence each other because such processes are emerging targets for intervention and prevention. PMID:24287013

  10. The origin of turtles: a paleontological perspective.

    Science.gov (United States)

    Joyce, Walter G

    2015-05-01

    The origin of turtles and their unusual body plan has fascinated scientists for the last two centuries. Over the course of the last decades, a broad sample of molecular analyses have favored a sister group relationship of turtles with archosaurs, but recent studies reveal that this signal may be the result of systematic biases affecting molecular approaches, in particular sampling, non-randomly distributed rate heterogeneity among taxa, and the use of concatenated data sets. Morphological studies, by contrast, disfavor archosaurian relationships for turtles, but the proposed alternative topologies are poorly supported as well. The recently revived paleontological hypothesis that the Middle Permian Eunotosaurus africanus is an intermediate stem turtle is now robustly supported by numerous characters that were previously thought to be unique to turtles and that are now shown to have originated over the course of tens of millions of years unrelated to the origin of the turtle shell. Although E. africanus does not solve the placement of turtles within Amniota, it successfully extends the stem lineage of turtles to the Permian and helps resolve some questions associated with the origin of turtles, in particular the non-composite origin of the shell, the slow origin of the shell, and the terrestrial setting for the origin of turtles. © 2015 Wiley Periodicals, Inc.

  11. Model reduction of nonlinear systems subject to input disturbances

    KAUST Repository

    Ndoye, Ibrahima

    2017-07-10

    The method of convex optimization is used as a tool for model reduction of a class of nonlinear systems in the presence of disturbances. It is shown that under some conditions the nonlinear disturbed system can be approximated by a reduced order nonlinear system with similar disturbance-output properties to the original plant. The proposed model reduction strategy preserves the nonlinearity and the input disturbance nature of the model. It guarantees a sufficiently small error between the outputs of the original and the reduced-order systems, and also maintains the properties of input-to-state stability. The matrices of the reduced order system are given in terms of a set of linear matrix inequalities (LMIs). The paper concludes with a demonstration of the proposed approach on model reduction of a nonlinear electronic circuit with additive disturbances.

  12. Proposed model for fuel-coolant mixing during a core-melt accident

    International Nuclear Information System (INIS)

    Corradini, M.L.

    1983-01-01

    If complete failure of normal and emergency coolant flow occurs in a light water reactor, fission product decay heat would eventually cause melting of the reactor fuel and cladding. The core melt may then slump into the lower plenum and later into the reactor cavity and contact residual liquid water. A model is proposed to describe the fuel-coolant mixing process upon contact. The model is compared to intermediate scale experiments being conducted at Sandia. The modelling of this mixing process will aid in understanding three important processes: (1) fuel debris sizes upon quenching in water, (2) the hydrogen source term during fuel quench, and (3) the rate of steam production. Additional observations of Sandia data indicate that the steam explosion is affected by this mixing process

  13. 78 FR 38091 - Airworthiness Criteria: Proposed Airship Design Criteria for Lockheed Martin Aeronautics Model...

    Science.gov (United States)

    2013-06-25

    ..., 2012 Lockheed Martin Aeronautics submitted an application for type certification for the model LMZ1M..., views, or arguments as they may desire. Commenters should identify the proposed design criteria on the... Lockheed Martin Aeronautics submitted an application for type certification for the model LMZ1M airship...

  14. [Social determinants of odontalgia in epidemiological studies: theoretical review and proposed conceptual model].

    Science.gov (United States)

    Bastos, João Luiz Dornelles; Gigante, Denise Petrucci; Peres, Karen Glazer; Nedel, Fúlvio Borges

    2007-01-01

    The epidemiological literature has been limited by the absence of a theoretical framework reflecting the complexity of causal mechanisms for the occurrence of health phenomena / disease conditions. In the field of oral epidemiology, such lack of theory also prevails, since dental caries the leading topic in oral research has been often studied through a biological and reductionist viewpoint. One of the most important consequences of dental caries is dental pain (odontalgia), which has received little attention in studies with sophisticated theoretical models and powerful designs to establish causal relationships. The purpose of this study is to review the scientific literature on the determinants of odontalgia and to discuss theories proposed for the explanation of the phenomenon. Conceptual models and emerging theories on the social determinants of oral health are revised, in an attempt to build up links with the bio-psychosocial pain model, proposing a more elaborate causal model for odontalgia. The framework suggests causal pathways between social structure and oral health through material, psychosocial and behavioral pathways. Aspects of the social structure are highlighted in order to relate them to odontalgia, stressing their importance in discussions of causal relationships in oral health research.

  15. Time series modeling and forecasting using memetic algorithms for regime-switching models.

    Science.gov (United States)

    Bergmeir, Christoph; Triguero, Isaac; Molina, Daniel; Aznarte, José Luis; Benitez, José Manuel

    2012-11-01

    In this brief, we present a novel model fitting procedure for the neuro-coefficient smooth transition autoregressive model (NCSTAR), as presented by Medeiros and Veiga. The model is endowed with a statistically founded iterative building procedure and can be interpreted in terms of fuzzy rule-based systems. The interpretability of the generated models and a mathematically sound building procedure are two very important properties of forecasting models. The model fitting procedure employed by the original NCSTAR is a combination of initial parameter estimation by a grid search procedure with a traditional local search algorithm. We propose a different fitting procedure, using a memetic algorithm, in order to obtain more accurate models. An empirical evaluation of the method is performed, applying it to various real-world time series originating from three forecasting competitions. The results indicate that we can significantly enhance the accuracy of the models, making them competitive to models commonly used in the field.

  16. The origin of the lower fourth molar in canids, inferred by individual variation

    Directory of Open Access Journals (Sweden)

    Masakazu Asahara

    2016-11-01

    Full Text Available Background An increase in tooth number is an exception during mammalian evolution. The acquisition of the lower fourth molar in the bat-eared fox (Otocyon megalotis, Canidae, Carnivora, Mammalia is one example; however, its developmental origin is not clear. In some canids (Canidae, individual variation exist as supernumerary molar M4. This study focuses on the acquisition of the lower fourth molar in canids and proposes that the inhibitory cascade model can explain its origin. Methods Occlusal view projected area of lower molars was determined from 740 mandibles obtained from Canis latrans, Nyctereutes procyonoides, and Urocyon cinereoargenteus museum specimens. For each molar, relative sizes of molars (M2/M1 and M3/M1 scores affected by inhibition/activation dynamics during development, were compared between individuals with and without supernumerary molar (M4. Results Possession of a supernumerary molar was associated with significantly larger M2/M1 score in Canis latrans, M3/M1 score in Nyctereutes procyonoides, and M2/M1 and M3/M1 scores in Urocyon cinereoargenteus compared to individuals of these species that lacked supernumerary molars. Discussion We propose that, in canids, the supernumerary fourth molar is attributable to reduced inhibition and greater activation during molar development. In the bat-eared fox, altered inhibition and activation dynamics of dental development during omnivorous-insectivorous adaptation may be a contributing factor in the origin of the lower fourth molar.

  17. AN EFFECTIVE RISK-PREVENTIVE MODEL PROPOSAL FOR OCCUPATIONAL ACCIDENTS AT SHIPYARDS

    Directory of Open Access Journals (Sweden)

    Ozge Acuner

    2016-03-01

    Full Text Available According to the statistics of occupational accidents, it is observed that the number of accidents occurred in shipbuilding industry is high and the rate of deaths and serious injuries among these accidents is higher than in other industries. However, the number of the studies to prevent these accidents in both industrial and scientific practices is considerably low. Therefore, the objective of this study is to develop an efficient risk preventive model in accordance with occupational health and safety regulations for industrial organizations. The approach proposed in this study differs from those described in the literature, because it is based on fuzzy set theory in order to cope with uncertainties on probability and severity definitions in terms of occupational health and safety. Furthermore, in this paper, risk severity is considered in terms of harm to worker, harm to environment, and harm to hardware, whereas in the literature, risk severity is generally considered solely in terms of only harm to worker. Then, risk magnitude is obtained by utilizing fuzzy inference system. The proposed approach is applied to a shipyard located in the Marmara Region in order to illustrate the applicability of the model.

  18. An original state equation for argillite

    International Nuclear Information System (INIS)

    Cariou, S.; Dormieux, L.; Skoczylas, F.

    2010-01-01

    Document available in extended abstract form only. Argillite is available in large quantities in France and exhibits a very small permeability: that is the reason why it is an excellent candidate for the storage of nuclear waste depositories. This study focuses particularly on argillite from Meuse-Haute-Marne (East of France) located 500 m deep. Following the observation that Biot theory does not permit us to explain some of our experiments, we propose in this contribution to use the tools of continuum micro-mechanics in order to develop a macroscopic state equation that would be consistent with our experimental data. In order to apply homogenization tools to argillite, the first step is to describe the microstructure of this material. Argillite can be modelled as a multi-scale material: - At the macro-scale, argillite looks like a homogenized material. - At the meso-scale, a shale matrix surrounding some inclusions can be distinguished. - At the micro-scale, the shale matrix reveals to be made of a solid phase and of a partially saturated porous network; capillary effects are taken into account at this scale. - At the nano-scale, the solid phase is not homogeneous but is a set of particles that are parallel platelets with an electrolyte in-between; the solid phase is not physically inert with regard to water in the porous network; first, liquid pressure in the electrolyte exists and is equal to liquid pressure in the porous network; then, the unbalance between the ion concentration in-between the platelets building up the solid phase and the ion concentration in the porous network implies an overpressure in the electrolyte. This complex model of argillite leads us though several homogenization steps to an original macroscopic state equation. We propose to compare this state equation with experimental data. Results of a poro-mechanical test run on a partially saturated sample of argillite are shown. One can read that the deformations of the sample are identical

  19. Repeated extragenic sequences in prokaryotic genomes: a proposal for the origin and dynamics of the RUP element in Streptococcus pneumoniae.

    Science.gov (United States)

    Oggioni, M R; Claverys, J P

    1999-10-01

    A survey of all Streptococcus pneumoniae GenBank/EMBL DNA sequence entries and of the public domain sequence (representing more than 90% of the genome) of an S. pneumoniae type 4 strain allowed identification of 108 copies of a 107-bp-long highly repeated intergenic element called RUP (for repeat unit of pneumococcus). Several features of the element, revealed in this study, led to the proposal that RUP is an insertion sequence (IS)-derivative that could still be mobile. Among these features are: (1) a highly significant homology between the terminal inverted repeats (IRs) of RUPs and of IS630-Spn1, a new putative IS of S. pneumoniae; and (2) insertion at a TA dinucleotide, a characteristic target of several members of the IS630 family. Trans-mobilization of RUP is therefore proposed to be mediated by the transposase of IS630-Spn1. To account for the observation that RUPs are distributed among four subtypes which exhibit different degrees of sequence homogeneity, a scenario is invoked based on successive stages of RUP mobility and non-mobility, depending on whether an active transposase is present or absent. In the latter situation, an active transposase could be reintroduced into the species through natural transformation. Examination of sequences flanking RUP revealed a preferential association with ISs. It also provided evidence that RUPs promote sequence rearrangements, thereby contributing to genome flexibility. The possibility that RUP preferentially targets transforming DNA of foreign origin and subsequently favours disruption/rearrangement of exogenous sequences is discussed.

  20. Planetary Environments and Origins of Life

    Directory of Open Access Journals (Sweden)

    Ollivier Marc

    2014-02-01

    Full Text Available The present strategies proposed for the search for the origins of life and for extra-terrestrial life are mainly based on Earth-life and its adaptation along geological eras to the Earth environment. These strategies should however face the difficulty that one cannot as yet accurately date the appearance of life on Earth, and consequently one cannot identify a chronology of phenomena related to the transition from the non-living to the living and the dependence of these phenomena on the Earth environment. In this paper, we present new approaches to search for the origins of life on the Earth and next, for life on exoplanets. This study is based on our experience gained at the head of the CNRSc interdisciplinary research initiative "Environnements Planétaires et Origines de la Vie (EPOVd, and on the analysis of the projects the initiative funded.

  1. Recombination facilitates neofunctionalization of duplicate genes via originalization

    Directory of Open Access Journals (Sweden)

    Huang Ren

    2010-06-01

    Full Text Available Abstract Background Recently originalization was proposed to be an effective way of duplicate-gene preservation, in which recombination provokes the high frequency of original (or wild-type allele on both duplicated loci. Because the high frequency of wild-type allele might drive the arising and accumulating of advantageous mutation, it is hypothesized that recombination might enlarge the probability of neofunctionalization (Pneo of duplicate genes. In this article this hypothesis has been tested theoretically. Results Results show that through originalization recombination might not only shorten mean time to neofunctionalizaiton, but also enlarge Pneo. Conclusions Therefore, recombination might facilitate neofunctionalization via originalization. Several extensive applications of these results on genomic evolution have been discussed: 1. Time to nonfunctionalization can be much longer than a few million generations expected before; 2. Homogenization on duplicated loci results from not only gene conversion, but also originalization; 3. Although the rate of advantageous mutation is much small compared with that of degenerative mutation, Pneo cannot be expected to be small.

  2. Modeling of processes of an adaptive business management

    Directory of Open Access Journals (Sweden)

    Karev Dmitry Vladimirovich

    2011-04-01

    Full Text Available On the basis of the analysis of systems of adaptive management board business proposed the original version of the real system of adaptive management, the basis of which used dynamic recursive model cash flow forecast and real data. Proposed definitions and the simulation of scales and intervals of model time in the control system, as well as the thresholds observations and conditions of changing (correction of the administrative decisions. The process of adaptive management is illustrated on the basis proposed by the author of the script of development of business.

  3. Animal evolution: stiff or squishy notochord origins?

    Science.gov (United States)

    Hejnol, Andreas; Lowe, Christopher J

    2014-12-01

    The notochord is considered an evolutionary novelty and one of the defining characters of chordates. A new study of an annelid challenges this view and proposes an earlier evolutionary origin in the most recent common ancestor of chordates and annelids. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Sibling influence on mexican-origin adolescents' deviant and sexual risk behaviors: the role of sibling modeling.

    Science.gov (United States)

    Whiteman, Shawn D; Zeiders, Katharine H; Killoren, Sarah E; Rodriguez, Sue Annie; Updegraff, Kimberly A

    2014-05-01

    A growing body of research indicates that siblings uniquely influence each other's health risk behaviors during adolescence and young adulthood. Mechanisms underlying these associations, however, are largely unknown because they are rarely tested directly. The present study addressed this gap by examining the role of sibling modeling in explaining changes in Mexican-origin youths' deviant and sexual risk behaviors over time. The sample included 380 Mexican-origin siblings (older sibling age: M = 21.18, SD = 1.59; younger sibling age: M = 18.19, SD = .46) from (N = 190) families. Participants provided self-reports of their sibling relationship qualities, including modeling, as well as their engagement in deviant and sexual risk-taking behaviors in two home interviews across a 2-year span. A series of residualized regression models revealed that younger siblings' perceptions of modeling moderated the links between older siblings' deviant and sexual risk behaviors and younger siblings' subsequent behaviors in those same domains. Specifically, high levels of modeling predicted stronger associations between older siblings' earlier and younger siblings' later risk behaviors controlling for younger siblings' earlier behaviors as well as variables that have been used as proxies for social learning in previous research. Social learning mechanisms, especially modeling, are salient processes through which older siblings transmit norms and expectations regarding participation in health risk behaviors. Future research should continue to explore the ways in which siblings influence each other because such processes are emerging targets for intervention and prevention. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  5. Proposal of a Modelling of the Innovation Process in an International Manufacturing Company

    Directory of Open Access Journals (Sweden)

    Pauline Lacom

    2017-07-01

    Full Text Available Nowadays, to cope with the competition, and to ensure the durability of their activities, companies have to be able to innovate. Manufacturing companies operating in a B2B market often perceive innovation as a technological result. However, innovation is often more characterized as a process. The needs of the users, and not only the technology, can achieve innovation. In this context, our paper intends to determine how to involve better the users in the innovation process of an international manufacturing company, which is, according to us, representative of the current manufacturing companies. The aim of our research paper is to help manufacturing companies to manage innovation led by users, and to implement their innovation process so that they will be able to set up specific tools for each action of the process. The study proposes a diagram-based language Structured Analysis and Design Technique (SADT that is based on the normative guide FD X50-271 of the French national organization for standardization (AFNOR. The SADT model we propose usefully complements this guide, to make the innovation process more understandable, practical and operational, for manufacturing companies, which are often helpless when faced with the subject. A critical analysis of the model we propose completed in a manufacturing company through semi-structured interviews of the innovation team and questionnaire for all the employees shows the application of the model in the company.

  6. Statistical methods for improving verification of claims of origin for Italian wines based on stable isotope ratios

    International Nuclear Information System (INIS)

    Dordevic, N.; Wehrens, R.; Postma, G.J.; Buydens, L.M.C.; Camin, F.

    2012-01-01

    Highlights: ► The assessment of claims of origin is of enormous economic importance for DOC and DOCG wines. ► The official method is based on univariate statistical tests of H, C and O isotopic ratios. ► We consider 5220 Italian wine samples collected in the period 2000–2010. ► Multivariate statistical analysis leads to much better specificity and easier detection of false claims of origin. ► In the case of multi-modal data, mixture modelling provides additional improvements. - Abstract: Wine derives its economic value to a large extent from geographical origin, which has a significant impact on the quality of the wine. According to the food legislation, wines can be without geographical origin (table wine) and wines with origin. Wines with origin must have characteristics which are essential due to its region of production and must be produced, processed and prepared, exclusively within that region. The development of fast and reliable analytical methods for the assessment of claims of origin is very important. The current official method is based on the measurement of stable isotope ratios of water and alcohol in wine, which are influenced by climatic factors. The results in this paper are based on 5220 Italian wine samples collected in the period 2000–2010. We evaluate the univariate approach underlying the official method to assess claims of origin and propose several new methods to get better geographical discrimination between samples. It is shown that multivariate methods are superior to univariate approaches in that they show increased sensitivity and specificity. In cases where data are non-normally distributed, an approach based on mixture modelling provides additional improvements.

  7. QAM: PROPOSED MODEL FOR QUALITY ASSURANCE IN CBSS

    Directory of Open Access Journals (Sweden)

    Latika Kharb

    2015-08-01

    Full Text Available Component-based software engineering (CBSE / Component-Based Development (CBD lays emphasis on decomposition of the engineered systems into functional or logical components with well-defined interfaces used for communication across the components. Component-based software development approach is based on the idea to develop software systems by selecting appropriate off-the-shelf components and then to assemble them with a well-defined software architecture. Because the new software development paradigm is much different from the traditional approach, quality assurance for component-based software development is a new topic in the software engineering research community. Because component-based software systems are developed on an underlying process different from that of the traditional software, their quality assurance model should address both the process of components and the process of the overall system. Quality assurance for component-based software systems during the life cycle is used to analyze the components for achievement of high quality component-based software systems. Although some Quality assurance techniques and component based approach to software engineering have been studied, there is still no clear and well-defined standard or guidelines for component-based software systems. Therefore, identification of the quality assurance characteristics, quality assurance models, quality assurance tools and quality assurance metrics, are under urgent need. As a major contribution in this paper, I have proposed QAM: Quality Assurance Model for component-based software development, which covers component requirement analysis, component development, component certification, component architecture design, integration, testing, and maintenance.

  8. Leak Signature Space: An Original Representation for Robust Leak Location in Water Distribution Networks

    Directory of Open Access Journals (Sweden)

    Myrna V. Casillas

    2015-03-01

    Full Text Available In this paper, an original model-based scheme for leak location using pressure sensors in water distribution networks is introduced. The proposed approach is based on a new representation called the Leak Signature Space (LSS that associates a specific signature to each leak location being minimally affected by leak magnitude. The LSS considers a linear model approximation of the relation between pressure residuals and leaks that is projected onto a selected hyperplane. This new approach allows to infer the location of a given leak by comparing the position of its signature with other leak signatures. Moreover, two ways of improving the method’s robustness are proposed. First, by associating a domain of influence to each signature and second, through a time horizon analysis. The efficiency of the method is highlighted by means of a real network using several scenarios involving different number of sensors and considering the presence of noise in the measurements.

  9. Models for the structure and origin of bipolar nebulae

    International Nuclear Information System (INIS)

    Morris, M.

    1981-01-01

    The appearance of bipolar nebulae-symmetric reflection nebulae centered on evolved, mass-losing stars-can most simply be accounted for in terms of an axisymmetric distribution of outflowing dust in which the dust is concentrated towards an equatorial plane and declines monotonically with latitude above that plane. The symmetrically placed ''horns'' that can be seen radiating out of some bipolar nebulae, notably GL 2688, are a natural consequence of such a dust distribution if, at some latitude, the radial optical depth to starlight falls rapidly below unity. Several models of bipolar nebulae are presented. These structural models for bipolar nebulae lead in turn to an investigation of how such a geometry might arise. Although nonradial pulsation, rotationally forced mass ejection by a single star, and mass loss from a common envelope binary are all considered, the most attractive origin for bipolar nebulae is a binary star system in which the primary is evolving up the red giant branch to the point at which its radius approaches its tidal radius. If this occurs before corotation of the primary with the secondary's orbit can be achieved, then matter from the primary's enveloped can be gravitationally ejected from the system by the secondary, the ejected material being concentrated toward the system's equatorial plane. Numerical models of this phenomenon show that gravitational ejection from an asynchronous binary system easily leads to terminal outflow velocities in the observed range (20--50 km s -1 ), and that the rate of mass loss and the time scale over which the mass ejection takes place are consistent with observations if the particle density in the outer layers of the primary's atmosphere from which the material is extracted is in the range 10 14 --10 15 cm -3 . If this hypothesis is applicable, bipolar nebulae will probably become planetary nebulae, as previously suggested on observational grounds

  10. La voce senz’anima: origine e storia del Vocoder

    Directory of Open Access Journals (Sweden)

    Paolo Zavagna

    2013-08-01

    Full Text Available A review of the cultural origins of the speaking machines is proposed. These origins are identified in the separation between soul and body, proposed by Descartes. The speaking machines, and then the vocoder, are substantially formed by a controlled part and an automatic part; in the voder, the synthetic speaker is directly controlled by a human being, conversely in the vocoder an authomatic process is implemented. Through historical examples such as the ‘automata’ by Mical, Kratzenstein, von Kempelen, Wheatstone, Helmoltz, until the invention of the Dudley’s vocoder, are described a growth and a stratification of devices and synthesizers applied to varied fields (signal representation, encrypted transmission, medical apparatus, cybernetic, music. The historical period treated ideally ends with Dolson’s article written in 1986, “The Phase Vocoder: A Tutorial”. Through musical examples is described the origin of control data handling in composition. The musical application of the phase vocoder describes the distinction between control and synthesis better than other technologies. Both control (parameter values and synthesis (instruments design are compositional problems that involve all the electroacoustic music composers.

  11. Coupled geochemical/hydrogeological modelling to assess the origin of salinity at the Tono area (Japan)

    International Nuclear Information System (INIS)

    Guimera, Jordi; Ruiz, Eduardo; Luna, Miguel; Arcos, David; Jordana, Salvador; Saegusa, Hiromitsu

    2005-01-01

    Numerical models are powerful tools for the characterization of groundwater flow, especially when integrating geochemical and hydrogeological data. This paper describes modeling exercises performed in the area surrounding the Mizunami Underground Research Laboratory (MIU) Construction Site in central Japan. A particular issue being investigated at the MIU Site is the presence of saline water detected at depth in certain boreholes. The main objective of this study is to develop conceptual physical models for the origin of this salinity and to test these conceptual models using numerical modeling techniques. One scenario being investigated is that the saline fluids represent residual Miocene age seawater which has been slightly altered by water-rock interactions. It is likely that during Miocene times, seawater inundated the Tono area. This hypothesis is partially supported by carbon and oxygen isotopic data of the calcite fracture filling materials. (author)

  12. A statistical model for estimating maternal-zygotic interactions and parent-of-origin effects of QTLs for seed development.

    Directory of Open Access Journals (Sweden)

    Yanchun Li

    Full Text Available Proper development of a seed requires coordinated exchanges of signals among the three components that develop side by side in the seed. One of these is the maternal integument that encloses the other two zygotic components, i.e., the diploid embryo and its nurturing annex, the triploid endosperm. Although the formation of the embryo and endosperm contains the contributions of both maternal and paternal parents, maternally and paternally derived alleles may be expressed differently, leading to a so-called parent-of-origin or imprinting effect. Currently, the nature of how genes from the maternal and zygotic genomes interact to affect seed development remains largely unknown. Here, we present a novel statistical model for estimating the main and interaction effects of quantitative trait loci (QTLs that are derived from different genomes and further testing the imprinting effects of these QTLs on seed development. The experimental design used is based on reciprocal backcrosses toward both parents, so that the inheritance of parent-specific alleles could be traced. The computing model and algorithm were implemented with the maximum likelihood approach. The new strategy presented was applied to study the mode of inheritance for QTLs that control endoreduplication traits in maize endosperm. Monte Carlo simulation studies were performed to investigate the statistical properties of the new model with the data simulated under different imprinting degrees. The false positive rate of imprinting QTL discovery by the model was examined by analyzing the simulated data that contain no imprinting QTL. The reciprocal design and a series of analytical and testing strategies proposed provide a standard procedure for genomic mapping of QTLs involved in the genetic control of complex seed development traits in flowering plants.

  13. The Origin of Inertia and Matter as a Superradiant Phase Transition of Quantum Vacuum

    Science.gov (United States)

    Maxmilian Caligiuri, Luigi

    Mass is one of the most important concepts in physics and its real understanding represents the key for the formulation of any consistent physical theory. During the past years, a very interesting model of inertial and gravitational mass as the result of the reaction interaction between the charged particles (electrons and quarks) contained in a given body and a suitable "fraction" of QED Zero Point Fields confined within an ideal resonant cavity, associated to the same body, has been proposed by Haish, Rueda and Puthoff. More recently, the author showed that this interpretation is consistent with a picture of mass (both inertial and gravitational) as the seat of ZPF standing waves whose presence reduces quantum vacuum energy density inside the resonant cavity ideally associated to the body volume. Nevertheless so far, the ultimate physical origin of such resonant cavity as well as the mechanism able to "select" the fraction of ZPF electromagnetic modes interacting within it, remained unrevealed. In this paper, basing on the framework of QED coherence in condensed matter, we'll show mass can be viewed as the result of a spontaneous superradiant phase transition of quantum vacuum giving rise to a more stable, energetically favored, oscopic quantum state characterized by an ensemble of coherence domains, "trapping" the coherent ZPF fluctuations inside a given volume just acting as a resonant cavity. Our model is then able to explain the "natural" emergence of the ideal resonant cavity speculated by Haish, Rueda and Puthoff and its defining parameters as well as the physical mechanism selecting the fraction of ZPF interacting with the body particles. Finally, a generalization of the model to explain the origin of mass of elementary particles is proposed also suggesting a new understanding of Compton's frequency and De Broglie's wavelength. Our results indicates both inertia and matter could truly originate from coherent interaction between quantum matter-wave and

  14. The traceability of renewable energies: the guarantees of origin

    International Nuclear Information System (INIS)

    2017-03-01

    The guarantee of origin has been initially designed by the European Union as a mechanism of support for renewable energies. It is an electronic document which allows an electric power provider to guarantee to its client the origin of the energy it sells him. This document presents the legal background of this guarantee, briefly describes the life cycle of this guarantee, proposes a brief discussion of recent legal evolutions, and briefly discusses its future

  15. Les origines de l’entrepreneur schumpétérien The Origins of the Schumpeterian Entrepreneur

    Directory of Open Access Journals (Sweden)

    Jean-Jacques Gislain

    2012-11-01

    Full Text Available Cet article examine les deux origines, logique dans la théorie économique et historique dans l’histoire de la pensée économique, de l’entrepreneur chez J. A. Schumper. L’origine logique réside dans la nécessité analytique de construire un « type entrepreneur », comme type particulier d’agent économique, pour rendre intelligible le processus de transformation économique. Ce type permet le passage de l’analyse statique, le circuit walrasien, à celle dynamique de l’évolution économique. L’origine historique de ce type entrepreneur ne fait pas de Schumpeter un auteur aussi original que l’on pourrait le penser. Quelques années avant, de nombreux auteurs importants, et bien connus de Schumper, avaient déjà proposé des descriptions de l’entrepreneur très proches de celle de Schumpeter. Parmi ceux-ci, Max Weber, Werner Sombart, Alfred Marshall, Paul Leroy-Beaulieu et Friedrich von Wieser sont ici étudiés.This article examines both origins, logic in the economic theory and historic in the history of the economic thought, of the Schumpeterian entrepreneur. The logical origin lies in the analytical necessity of building a "typify entrepreneur", as particular type of economic agent, to make understandable the process of economic transformation. This type allows the passage of the static analysis, the walrasian circuit, that dynamics of the economic evolution. The historic origin of this type entrepreneur does not make Schumpeter a so original author as we could think of it. Some years before, numerous important authors, and known well by Schumper, had already proposed the descriptions of the entrepreneur very close to that of Schumpeter. Among these, Max Weber, Werner Sombart, Alfred Marshall, Paul Leroy-Beaulieu and Friedrich von Wieser are studied here.

  16. Isthmus Stem Cells Are the Origins of Metaplasia in the Gastric Corpus

    Directory of Open Access Journals (Sweden)

    Yoku Hayakawa MD,, PhD

    2017-07-01

    Full Text Available The acquisition of genetic/epigenetic mutations in long-lived gastrointestinal stem cells leads to the development of cancer, as well as precancerous lesions such as metaplasia and dysplasia. In the proximal stomach corpus, this model of progression from stem cells has been supported by studies in mice and human beings, showing abundant proliferation in the isthmus and clonal expansion of mutated cells from the stem cell region. An alternative theory proposes that gastric metaplasia arises from mature differentiated chief cells. Despite reports of low levels of proliferation in chief cells in acute injury models, there is little evidence for reprogramming of chief cells into long-lived stem cells that continuously supply progeny over time. Critical flaws in the chief cell transdifferentiation theory include the definition of acute SPEM, the chief cell-damaging effect of chemical reagents, and the specificity of chief cell lineage tracing. In contrast, there is now strong evidence regarding the stem cell origins of gastric metaplasia that refutes the transdifferentiation theory. Here, we briefly review the history and definition of gastric metaplasia, and outline in detail the evidence that supports the stem cell origin of metaplasia.

  17. Tracing the evolutionary origin of vertebrate skeletal tissues: insights from cephalochordate amphioxus.

    Science.gov (United States)

    Yong, Luok Wen; Yu, Jr-Kai

    2016-08-01

    Vertebrate mineralized skeletal tissues are widely considered as an evolutionary novelty. Despite the importance of these tissues to the adaptation and radiation of vertebrate animals, the evolutionary origin of vertebrate skeletal tissues remains largely unclear. Cephalochordates (Amphioxus) occupy a key phylogenetic position and can serve as a valuable model for studying the evolution of vertebrate skeletal tissues. Here we summarize recent advances in amphioxus developmental biology and comparative genomics that can help to elucidate the evolutionary origins of the vertebrate skeletal tissues and their underlying developmental gene regulatory networks (GRN). By making comparisons to the developmental studies in vertebrate models and recent discoveries in paleontology and genomics, it becomes evident that the collagen matrix-based connective tissues secreted by the somite-derived cells in amphioxus likely represent the rudimentary skeletal tissues in chordates. We propose that upon the foundation of this collagenous precursor, novel tissue mineralization genes that arose from gene duplications were incorporated into an ancestral mesodermal GRN that makes connective and supporting tissues, leading to the emergence of highly-mineralized skeletal tissues in early vertebrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Automating Construction of Machine Learning Models With Clinical Big Data: Proposal Rationale and Methods.

    Science.gov (United States)

    Luo, Gang; Stone, Bryan L; Johnson, Michael D; Tarczy-Hornoch, Peter; Wilcox, Adam B; Mooney, Sean D; Sheng, Xiaoming; Haug, Peter J; Nkoy, Flory L

    2017-08-29

    To improve health outcomes and cut health care costs, we often need to conduct prediction/classification using large clinical datasets (aka, clinical big data), for example, to identify high-risk patients for preventive interventions. Machine learning has been proposed as a key technology for doing this. Machine learning has won most data science competitions and could support many clinical activities, yet only 15% of hospitals use it for even limited purposes. Despite familiarity with data, health care researchers often lack machine learning expertise to directly use clinical big data, creating a hurdle in realizing value from their data. Health care researchers can work with data scientists with deep machine learning knowledge, but it takes time and effort for both parties to communicate effectively. Facing a shortage in the United States of data scientists and hiring competition from companies with deep pockets, health care systems have difficulty recruiting data scientists. Building and generalizing a machine learning model often requires hundreds to thousands of manual iterations by data scientists to select the following: (1) hyper-parameter values and complex algorithms that greatly affect model accuracy and (2) operators and periods for temporally aggregating clinical attributes (eg, whether a patient's weight kept rising in the past year). This process becomes infeasible with limited budgets. This study's goal is to enable health care researchers to directly use clinical big data, make machine learning feasible with limited budgets and data scientist resources, and realize value from data. This study will allow us to achieve the following: (1) finish developing the new software, Automated Machine Learning (Auto-ML), to automate model selection for machine learning with clinical big data and validate Auto-ML on seven benchmark modeling problems of clinical importance; (2) apply Auto-ML and novel methodology to two new modeling problems crucial for care

  19. Two-Dimensional Model Test Study of New Western Breakwater Proposal for Port of Hanstholm

    OpenAIRE

    Eldrup, Mads Røge; Andersen, Thomas Lykke

    2016-01-01

    The present report presents results from a two-dimensional model test study carried out at Aalborg University in December 2016 with the proposed trunk section for the new western breakwater in Port of Hanstholm. The objectives of the model tests were to study the stability of the armour layer, toe erosion, overtopping and transmission. The scale used for the model tests was 1:61.5. Unless otherwise specified all values given in this report are prototype values converted from the model to prot...

  20. Two-Dimensional Model Test Study of New Western Breakwater Proposal for Port of Hanstholm

    DEFF Research Database (Denmark)

    Eldrup, Mads Røge; Andersen, Thomas Lykke

    The present report presents results from a two-dimensional model test study carried out at Aalborg University in December 2016 with the proposed trunk section for the new western breakwater in Port of Hanstholm. The objectives of the model tests were to study the stability of the armour layer, toe...... erosion, overtopping and transmission. The scale used for the model tests was 1:61.5. Unless otherwise specified all values given in this report are prototype values converted from the model to prototype according to the Froude model law....

  1. Origins of life: a problem for physics, a key issues review

    Science.gov (United States)

    Imari Walker, Sara

    2017-09-01

    The origins of life stands among the great open scientific questions of our time. While a number of proposals exist for possible starting points in the pathway from non-living to living matter, these have so far not achieved states of complexity that are anywhere near that of even the simplest living systems. A key challenge is identifying the properties of living matter that might distinguish living and non-living physical systems such that we might build new life in the lab. This review is geared towards covering major viewpoints on the origin of life for those new to the origin of life field, with a forward look towards considering what it might take for a physical theory that universally explains the phenomenon of life to arise from the seemingly disconnected array of ideas proposed thus far. The hope is that a theory akin to our other theories in fundamental physics might one day emerge to explain the phenomenon of life, and in turn finally permit solving its origins.

  2. Metal enrichment in the Fermi bubbles as a probe of their origin

    Science.gov (United States)

    Inoue, Yoshiyuki; Nakashima, Shinya; Tahara, Masaya; Kataoka, Jun; Totani, Tomonori; Fujita, Yutaka; Sofue, Yoshiaki

    2015-06-01

    The Fermi bubbles are gigantic gamma-ray structures in our Galaxy. The physical origin of the bubbles is still under debate. The leading scenarios can be divided into two categories. One is nuclear star-forming activity similar to extragalactic starburst galaxies and the other is past active galactic nucleus (AGN)-like activity of the Galactic center supermassive black hole. In this letter, we propose that metal abundance measurements will provide an important clue to probe their origin. Based on a simple spherically symmetric bubble model, we find that the generated metallicity and abundance patterns of the bubbles' gas strongly depend on assumed star formation or AGN activities. Star formation scenarios predict higher metallicities and abundance ratios of [O/Fe] and [Ne/Fe] than AGN scenarios do because of supernovae ejecta. Furthermore, the resultant abundance depends on the gamma-ray emission process because different mass injection histories are required for the different gamma-ray emission processes due to the acceleration and cooling time scales of non-thermal particles. Future X-ray missions such as ASTRO-H and Athena will give a clue to probe the origin of the bubbles through abundance measurements with their high energy resolution instruments.

  3. Function of BRCA1 at a DNA Replication Origin

    National Research Council Canada - National Science Library

    Lieberman, Paul

    2004-01-01

    ... and allow efficient repair of damaged DNA. In this proposal, we present preliminary data that BRCA1 functions in a DNA checkpoint response for the origin of Epstein-Barr Virus DNA replication (Ori P...

  4. An enhanced Brinson model with modified kinetics for martensite transformation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Jin; Lee, Jung Ju [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Jeong, Ju-Won [Korea Aerospace Research Institute, Daejeon (Korea, Republic of); Lim, Jae Hyuk [Chonbuk National University, Jeonju (Korea, Republic of)

    2017-03-15

    We propose an enhanced Brinson model with modified kinetics for martensite transformation. Two additional material constants are considered to follow the stress-temperature diagram above austenite start temperature (As) along with treatment to keep the continuity of the martensite volume fraction and the path dependency of the phase transformation. To demonstrate the performance of the proposed model, we implement this algorithm into ABAQUS user subroutine, then conduct several numerical simulations and compare their results with SMA wire experiments as well as those of three-dimensional SMA constitutive models. From the results, it turns out that the proposed model is as accurate as the three-dimensional models and shows better accuracy over original Brinson model in terms of recovery stress.

  5. Relational models for knowledge sharing behavior

    NARCIS (Netherlands)

    Boer, N.I.; Berends, J.J.; Baalen, P.

    2011-01-01

    In this paper we explore the relational dimension of knowledge sharing behavior by proposing a comprehensive theoretical framework for studying knowledge sharing in organizations. This theoretical framework originates from (Fiske, 1991) and (Fiske, 1992) Relational Models Theory (RMT). The RMT

  6. A model for the thermodynamic analysis in a batch type fluidized bed dryer

    International Nuclear Information System (INIS)

    Özahi, Emrah; Demir, Hacımurat

    2013-01-01

    An original model for thermodynamic analysis of a batch type fluidized bed dryer is proposed herein considering two separate systems comprised of drying air medium as a control volume and particles to be dried as a control mass. By means of the proposed model, energetic and exergetic analyses of a drying column of a batch type fluidized bed dryer are carried out as an original contribution to literature since there is no such like model in which the analyses are performed considering two separate systems. The energetic efficiencies evaluated by means of the proposed model using the data in literature are compared with those in literature and a good conformity is satisfied with an acceptable error margin of ±9%. A new correlation is also developed with a mean deviation of ±10% in order to evaluate the energetic efficiency for not only corn drying process but also drying processes of other particles at inlet air temperature of 50 °C. Effects of air mass flow rate, mass of particle and ambient temperature on energetic and exergetic efficiencies are analyzed and some concluding remarks are highlighted for further studies. - Highlights: • Energetic and exergetic analyses of a batch type fluidized bed dryer are developed. • An original model is proposed for thermodynamic analyses in a fluidized bed dryer. • The proposed model is compared with the data in literature with an accuracy of ±9%. • Effect of air mass flow rate is more significant than that of ambient temperature. • Effect of mass of particle is more significant than that of ambient temperature

  7. On nonlinear reduced order modeling

    International Nuclear Information System (INIS)

    Abdel-Khalik, Hany S.

    2011-01-01

    When applied to a model that receives n input parameters and predicts m output responses, a reduced order model estimates the variations in the m outputs of the original model resulting from variations in its n inputs. While direct execution of the forward model could provide these variations, reduced order modeling plays an indispensable role for most real-world complex models. This follows because the solutions of complex models are expensive in terms of required computational overhead, thus rendering their repeated execution computationally infeasible. To overcome this problem, reduced order modeling determines a relationship (often referred to as a surrogate model) between the input and output variations that is much cheaper to evaluate than the original model. While it is desirable to seek highly accurate surrogates, the computational overhead becomes quickly intractable especially for high dimensional model, n ≫ 10. In this manuscript, we demonstrate a novel reduced order modeling method for building a surrogate model that employs only 'local first-order' derivatives and a new tensor-free expansion to efficiently identify all the important features of the original model to reach a predetermined level of accuracy. This is achieved via a hybrid approach in which local first-order derivatives (i.e., gradient) of a pseudo response (a pseudo response represents a random linear combination of original model’s responses) are randomly sampled utilizing a tensor-free expansion around some reference point, with the resulting gradient information aggregated in a subspace (denoted by the active subspace) of dimension much less than the dimension of the input parameters space. The active subspace is then sampled employing the state-of-the-art techniques for global sampling methods. The proposed method hybridizes the use of global sampling methods for uncertainty quantification and local variational methods for sensitivity analysis. In a similar manner to

  8. Proposal for Classifying the Severity of Speech Disorder Using a Fuzzy Model in Accordance with the Implicational Model of Feature Complexity

    Science.gov (United States)

    Brancalioni, Ana Rita; Magnago, Karine Faverzani; Keske-Soares, Marcia

    2012-01-01

    The objective of this study is to create a new proposal for classifying the severity of speech disorders using a fuzzy model in accordance with a linguistic model that represents the speech acquisition of Brazilian Portuguese. The fuzzy linguistic model was run in the MATLAB software fuzzy toolbox from a set of fuzzy rules, and it encompassed…

  9. 76 FR 68373 - Proposed Revision to Vintage Date Requirements

    Science.gov (United States)

    2011-11-04

    ... published in the Federal Register (42 FR 30517) on June 15, 1977, ATF noted that the wine industry advocated... Alcohol and Tobacco Tax and Trade Bureau proposes to amend its wine labeling regulations to allow a vintage date to appear on a wine that is labeled with a country as an appellation of origin. The proposal...

  10. Critical Values for Lawshe's Content Validity Ratio: Revisiting the Original Methods of Calculation

    Science.gov (United States)

    Ayre, Colin; Scally, Andrew John

    2014-01-01

    The content validity ratio originally proposed by Lawshe is widely used to quantify content validity and yet methods used to calculate the original critical values were never reported. Methods for original calculation of critical values are suggested along with tables of exact binomial probabilities.

  11. Production Decision Based on Discounted Price and Delivery Frequency for Garment Original Equipment Manufacturer with Constrained Capacity

    Institute of Scientific and Technical Information of China (English)

    HUO Yanfang; GU Yajie; HAN Lin; WANG Xize

    2017-01-01

    Original equipment manufacturers (OEM) have never been so important and powerful as it is today in garment manufacturing industry.The OEM supplier's production decisions always have a great impact on the market performance and the profits of a garment brand manufacturer.With constrained capacity and multiply buyers,how to make reasonable production decisions is an urgent problem for OEM suppliers.A price discount model with a single OEM supplier and two buyers is proposed to deal with the problem.Based on this model,the OEM supplier could satisfy buyers' demands and guarantee their profits as well through adjusting price and delivery frequency.A numerical example validates the validity of the model.

  12. Adjustment and Characterization of an Original Model of Chronic Ischemic Heart Failure in Pig

    Directory of Open Access Journals (Sweden)

    Laurent Barandon

    2010-01-01

    Full Text Available We present and characterize an original experimental model to create a chronic ischemic heart failure in pig. Two ameroid constrictors were placed around the LAD and the circumflex artery. Two months after surgery, pigs presented a poor LV function associated with a severe mitral valve insufficiency. Echocardiography analysis showed substantial anomalies in radial and circumferential deformations, both on the anterior and lateral surface of the heart. These anomalies in function were coupled with anomalies of perfusion observed in echocardiography after injection of contrast medium. No demonstration of myocardial infarction was observed with histological analysis. Our findings suggest that we were able to create and to stabilize a chronic ischemic heart failure model in the pig. This model represents a useful tool for the development of new medical or surgical treatment in this field.

  13. RNA Relics and Origin of Life

    Directory of Open Access Journals (Sweden)

    Laurent Vial

    2009-07-01

    Full Text Available A number of small RNA sequences, located in different non-coding sequences and highly preserved across the tree of life, have been suggested to be molecular fossils, of ancient (and possibly primordial origin. On the other hand, recent years have revealed the existence of ubiquitous roles for small RNA sequences in modern organisms, in functions ranging from cell regulation to antiviral activity. We propose that a single thread can be followed from the beginning of life in RNA structures selected only for stability reasons through the RNA relics and up to the current coevolution of RNA sequences; such an understanding would shed light both on the history and on the present development of the RNA machinery and interactions. After presenting the evidence (by comparing their sequences that points toward a common thread, we discuss a scenario of genome coevolution (with emphasis on viral infectious processes and finally propose a plan for the reevaluation of the stereochemical theory of the genetic code; we claim that it may still be relevant, and not only for understanding the origin of life, but also for a comprehensive picture of regulation in present-day cells.

  14. RNA Relics and Origin of Life

    Science.gov (United States)

    Demongeot, Jacques; Glade, Nicolas; Moreira, Andrés; Vial, Laurent

    2009-01-01

    A number of small RNA sequences, located in different non-coding sequences and highly preserved across the tree of life, have been suggested to be molecular fossils, of ancient (and possibly primordial) origin. On the other hand, recent years have revealed the existence of ubiquitous roles for small RNA sequences in modern organisms, in functions ranging from cell regulation to antiviral activity. We propose that a single thread can be followed from the beginning of life in RNA structures selected only for stability reasons through the RNA relics and up to the current coevolution of RNA sequences; such an understanding would shed light both on the history and on the present development of the RNA machinery and interactions. After presenting the evidence (by comparing their sequences) that points toward a common thread, we discuss a scenario of genome coevolution (with emphasis on viral infectious processes) and finally propose a plan for the reevaluation of the stereochemical theory of the genetic code; we claim that it may still be relevant, and not only for understanding the origin of life, but also for a comprehensive picture of regulation in present-day cells. PMID:20111682

  15. Parametric and non-parametric models for lifespan modeling of insulation systems in electrical machines

    OpenAIRE

    Salameh , Farah; Picot , Antoine; Chabert , Marie; Maussion , Pascal

    2017-01-01

    International audience; This paper describes an original statistical approach for the lifespan modeling of electric machine insulation materials. The presented models aim to study the effect of three main stress factors (voltage, frequency and temperature) and their interactions on the insulation lifespan. The proposed methodology is applied to two different insulation materials tested in partial discharge regime. Accelerated ageing tests are organized according to experimental optimization m...

  16. A Novel Modeling Method for Aircraft Engine Using Nonlinear Autoregressive Exogenous (NARX) Models Based on Wavelet Neural Networks

    Science.gov (United States)

    Yu, Bing; Shu, Wenjun; Cao, Can

    2018-05-01

    A novel modeling method for aircraft engine using nonlinear autoregressive exogenous (NARX) models based on wavelet neural networks is proposed. The identification principle and process based on wavelet neural networks are studied, and the modeling scheme based on NARX is proposed. Then, the time series data sets from three types of aircraft engines are utilized to build the corresponding NARX models, and these NARX models are validated by the simulation. The results show that all the best NARX models can capture the original aircraft engine's dynamic characteristic well with the high accuracy. For every type of engine, the relative identification errors of its best NARX model and the component level model are no more than 3.5 % and most of them are within 1 %.

  17. Modeling fault rupture hazard for the proposed repository at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Coppersmith, K.J.; Youngs, R.R.

    1992-01-01

    In this paper as part of the Electric Power Research Institute's High Level Waste program, the authors have developed a preliminary probabilistic model for assessing the hazard of fault rupture to the proposed high level waste repository at Yucca Mountain. The model is composed of two parts: the earthquake occurrence model that describes the three-dimensional geometry of earthquake sources and the earthquake recurrence characteristics for all sources in the site vicinity; and the rupture model that describes the probability of coseismic fault rupture of various lengths and amounts of displacement within the repository horizon 350 m below the surface. The latter uses empirical data from normal-faulting earthquakes to relate the rupture dimensions and fault displacement amounts to the magnitude of the earthquake. using a simulation procedure, we allow for earthquake occurrence on all of the earthquake sources in the site vicinity, model the location and displacement due to primary faults, and model the occurrence of secondary faulting in conjunction with primary faulting

  18. Collapse of the wave function models, ontology, origin, and implications

    CERN Document Server

    2018-01-01

    This is the first single volume about the collapse theories of quantum mechanics, which is becoming a very active field of research in both physics and philosophy. In standard quantum mechanics, it is postulated that when the wave function of a quantum system is measured, it no longer follows the Schrödinger equation, but instantaneously and randomly collapses to one of the wave functions that correspond to definite measurement results. However, why and how a definite measurement result appears is unknown. A promising solution to this problem are collapse theories in which the collapse of the wave function is spontaneous and dynamical. Chapters written by distinguished physicists and philosophers of physics discuss the origin and implications of wave-function collapse, the controversies around collapse models and their ontologies, and new arguments for the reality of wave function collapse. This is an invaluable resource for students and researchers interested in the philosophy of physics and foundations of ...

  19. The inverse niche model for food webs with parasites

    Science.gov (United States)

    Warren, Christopher P.; Pascual, Mercedes; Lafferty, Kevin D.; Kuris, Armand M.

    2010-01-01

    Although parasites represent an important component of ecosystems, few field and theoretical studies have addressed the structure of parasites in food webs. We evaluate the structure of parasitic links in an extensive salt marsh food web, with a new model distinguishing parasitic links from non-parasitic links among free-living species. The proposed model is an extension of the niche model for food web structure, motivated by the potential role of size (and related metabolic rates) in structuring food webs. The proposed extension captures several properties observed in the data, including patterns of clustering and nestedness, better than does a random model. By relaxing specific assumptions, we demonstrate that two essential elements of the proposed model are the similarity of a parasite's hosts and the increasing degree of parasite specialization, along a one-dimensional niche axis. Thus, inverting one of the basic rules of the original model, the one determining consumers' generality appears critical. Our results support the role of size as one of the organizing principles underlying niche space and food web topology. They also strengthen the evidence for the non-random structure of parasitic links in food webs and open the door to addressing questions concerning the consequences and origins of this structure.

  20. Local conformal symmetry in non-Riemannian geometry and the origin of physical scales

    Energy Technology Data Exchange (ETDEWEB)

    De Cesare, Marco [King' s College London, Theoretical Particle Physics and Cosmology Group, Department of Physics, London (United Kingdom); Moffat, John W. [Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada); Sakellariadou, Mairi [King' s College London, Theoretical Particle Physics and Cosmology Group, Department of Physics, London (United Kingdom); Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada)

    2017-09-15

    We introduce an extension of the Standard Model and General Relativity built upon the principle of local conformal invariance, which represents a generalization of a previous work by Bars, Steinhardt and Turok. This is naturally realized by adopting as a geometric framework a particular class of non-Riemannian geometries, first studied by Weyl. The gravitational sector is enriched by a scalar and a vector field. The latter has a geometric origin and represents the novel feature of our approach. We argue that physical scales could emerge from a theory with no dimensionful parameters, as a result of the spontaneous breakdown of conformal and electroweak symmetries. We study the dynamics of matter fields in this modified gravity theory and show that test particles follow geodesics of the Levi-Civita connection, thus resolving an old criticism raised by Einstein against Weyl's original proposal. (orig.)

  1. 25 Years оf Economic Reforms: Origins

    Directory of Open Access Journals (Sweden)

    Pavel Aleksandrovich Minakir

    2017-03-01

    Full Text Available The article considers the origins of economic reforms in modern Russia over the period of 25 years. It is shown that by 1991 consequences of unreasoned decisions and hasty actions have reached their culmination point and both political and economic attempts to realize the concept of 'convergence', to implant democracy in totalitarianism and the market in a centralized system of management have failed. At the same time it was impossible for the country's regions to maintain the inter-industry contractual communications and that had destroyed the 'center - regions' relations which had developed over the previous decades. The study and discussion of issues of the last 25 years of reform in Russia are proposed as the main theme for the journal 'Spatial Economics' in the year 2017. The goal of such studies and discussions should be to achieve a systemic i'pression about sources, trends, successes and failures of reforms, as only on this basis the initial model of the Russian socio-economic transformation can be developed. The researcher presumes that this model reviews each region as the most important element of the general system of knowledge and the resource and institutional policy constructed on its basis

  2. The origin of life and its methodological challenge.

    Science.gov (United States)

    Wächtershäuser, G

    1997-08-21

    The problem of the origin of life is discussed from a methodological point of view as an encounter between the teleological thinking of the historian and the mechanistic thinking of the chemist; and as the Kantian task of replacing teleology by mechanism. It is shown how the Popperian situational logic of historic understanding and the Popperian principle of explanatory power of scientific theories, when jointly applied to biochemistry, lead to a methodology of biochemical retrodiction, whereby common precursor functions are constructed for disparate successor functions. This methodology is exemplified by central tenets of the theory of the chemo-autotrophic origin of life: the proposal of a surface metabolism with a two-dimensional order; the basic polarity of life with negatively charged constituents on positively charged mineral surfaces; the surface-metabolic origin of phosphorylated sugar metabolism and nucleic acids; the origin of membrane lipids and of chemi-osmosis on pyrite surfaces; and the principles of the origin of the genetic machinery. The theory presents the early evolution of life as a process that begins with chemical necessity and winds up in genetic chance.

  3. An efficient study design to test parent-of-origin effects in family trios.

    Science.gov (United States)

    Yu, Xiaobo; Chen, Gao; Feng, Rui

    2017-11-01

    Increasing evidence has shown that genes may cause prenatal, neonatal, and pediatric diseases depending on their parental origins. Statistical models that incorporate parent-of-origin effects (POEs) can improve the power of detecting disease-associated genes and help explain the missing heritability of diseases. In many studies, children have been sequenced for genome-wide association testing. But it may become unaffordable to sequence their parents and evaluate POEs. Motivated by the reality, we proposed a budget-friendly study design of sequencing children and only genotyping their parents through single nucleotide polymorphism array. We developed a powerful likelihood-based method, which takes into account both sequence reads and linkage disequilibrium to infer the parental origins of children's alleles and estimate their POEs on the outcome. We evaluated the performance of our proposed method and compared it with an existing method using only genotypes, through extensive simulations. Our method showed higher power than the genotype-based method. When either the mean read depth or the pair-end length was reasonably large, our method achieved ideal power. When single parents' genotypes were unavailable or parental genotypes at the testing locus were not typed, both methods lost power compared with when complete data were available; but the power loss from our method was smaller than the genotype-based method. We also extended our method to accommodate mixed genotype, low-, and high-coverage sequence data from children and their parents. At presence of sequence errors, low-coverage parental sequence data may lead to lower power than parental genotype data. © 2017 WILEY PERIODICALS, INC.

  4. On the origin of hyperfast neutron stars

    NARCIS (Netherlands)

    Gvaramadze, V.V.; Gualandris, A.; Portegies Zwart, S.

    2007-01-01

    We propose an explanation for the origin of hyperfast neutron stars (e.g. PSR B1508+55, PSR B2224+65, RX J0822-4300) based on the hypothesis that they could be the remnants of a symmetric supernova explosion of a high-velocity massive star (or its helium core) which attained its peculiar velocity

  5. Improvement of MARS code reflood model

    International Nuclear Information System (INIS)

    Hwang, Moonkyu; Chung, Bub-Dong

    2011-01-01

    A specifically designed heat transfer model for the reflood process which normally occurs at low flow and low pressure was originally incorporated in the MARS code. The model is essentially identical to that of the RELAP5/MOD3.3 code. The model, however, is known to have under-estimated the peak cladding temperature (PCT) with earlier turn-over. In this study, the original MARS code reflood model is improved. Based on the extensive sensitivity studies for both hydraulic and wall heat transfer models, it is found that the dispersed flow film boiling (DFFB) wall heat transfer is the most influential process determining the PCT, whereas the interfacial drag model most affects the quenching time through the liquid carryover phenomenon. The model proposed by Bajorek and Young is incorporated for the DFFB wall heat transfer. Both space grid and droplet enhancement models are incorporated. Inverted annular film boiling (IAFB) is modeled by using the original PSI model of the code. The flow transition between the DFFB and IABF, is modeled using the TRACE code interpolation. A gas velocity threshold is also added to limit the top-down quenching effect. Assessment calculations are performed for the original and modified MARS codes for the Flecht-Seaset test and RBHT test. Improvements are observed in terms of the PCT and quenching time predictions in the Flecht-Seaset assessment. In case of the RBHT assessment, the improvement over the original MARS code is found marginal. A space grid effect, however, is clearly seen from the modified version of the MARS code. (author)

  6. Proposed Model for Integrating RAMS Method in the Design Process in Construction

    Directory of Open Access Journals (Sweden)

    Saad Al-Jibouri

    2010-05-01

    Full Text Available There is a growing trend in the Netherlands for outsourcing public construction activities to the private sector through the use of integrated contracts. There is also an increasing emphasis from public clients on the use of RAMS and life cycle costing (LCC in the design process of infrastructural projects to improve the performance of designed systems and optimize the project cost. RAMS is an acronym for `reliability, availability, maintainability and safety' and represents a collection of techniques to provide predictions of the performance targets of the required system. Increasingly, RAMS targets are being specified in invitation to tender or contract documents and the parties responsible for the design are required to provide evidence of its application in their design. Recent evidence from practice, complemented with a literature study, has shown that the knowledge and application of RAMS in infrastructural designs are in their infancy compared with other industrial sectors and many designers in construction do not have the necessary knowledge and experience to apply it. This paper describes a proposed model for the integration of RAMS and LCC into the design process in construction. A variation of the model for the application of RAMS in `design, build, finance and maintain' (DBFM contracts that include maintenance requirements is also proposed. The two models involve providing guidelines to simplify the application of RAMs by the designers. The model has been validated for its practicality and usefulness during a workshop by experienced designers. DOI: 10.3763/aedm.2008.0100 Published in the Journal AEDM - Volume 5, Number 4, 2009 , pp. 179-192(14

  7. Statistical methods for improving verification of claims of origin for Italian wines based on stable isotope ratios

    Energy Technology Data Exchange (ETDEWEB)

    Dordevic, N.; Wehrens, R. [IASMA Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010 San Michele all' Adige (Italy); Postma, G.J.; Buydens, L.M.C. [Radboud University Nijmegen, Institute for Molecules and Materials, Analytical Chemistry, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Camin, F., E-mail: federica.camin@fmach.it [IASMA Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010 San Michele all' Adige (Italy)

    2012-12-13

    Highlights: Black-Right-Pointing-Pointer The assessment of claims of origin is of enormous economic importance for DOC and DOCG wines. Black-Right-Pointing-Pointer The official method is based on univariate statistical tests of H, C and O isotopic ratios. Black-Right-Pointing-Pointer We consider 5220 Italian wine samples collected in the period 2000-2010. Black-Right-Pointing-Pointer Multivariate statistical analysis leads to much better specificity and easier detection of false claims of origin. Black-Right-Pointing-Pointer In the case of multi-modal data, mixture modelling provides additional improvements. - Abstract: Wine derives its economic value to a large extent from geographical origin, which has a significant impact on the quality of the wine. According to the food legislation, wines can be without geographical origin (table wine) and wines with origin. Wines with origin must have characteristics which are essential due to its region of production and must be produced, processed and prepared, exclusively within that region. The development of fast and reliable analytical methods for the assessment of claims of origin is very important. The current official method is based on the measurement of stable isotope ratios of water and alcohol in wine, which are influenced by climatic factors. The results in this paper are based on 5220 Italian wine samples collected in the period 2000-2010. We evaluate the univariate approach underlying the official method to assess claims of origin and propose several new methods to get better geographical discrimination between samples. It is shown that multivariate methods are superior to univariate approaches in that they show increased sensitivity and specificity. In cases where data are non-normally distributed, an approach based on mixture modelling provides additional improvements.

  8. Contextualising primate origins--an ecomorphological framework.

    Science.gov (United States)

    Soligo, Christophe; Smaers, Jeroen B

    2016-04-01

    Ecomorphology - the characterisation of the adaptive relationship between an organism's morphology and its ecological role - has long been central to theories of the origin and early evolution of the primate order. This is exemplified by two of the most influential theories of primate origins: Matt Cartmill's Visual Predation Hypothesis, and Bob Sussman's Angiosperm Co-Evolution Hypothesis. However, the study of primate origins is constrained by the absence of data directly documenting the events under investigation, and has to rely instead on a fragmentary fossil record and the methodological assumptions inherent in phylogenetic comparative analyses of extant species. These constraints introduce particular challenges for inferring the ecomorphology of primate origins, as morphology and environmental context must first be inferred before the relationship between the two can be considered. Fossils can be integrated in comparative analyses and observations of extant model species and laboratory experiments of form-function relationships are critical for the functional interpretation of the morphology of extinct species. Recent developments have led to important advancements, including phylogenetic comparative methods based on more realistic models of evolution, and improved methods for the inference of clade divergence times, as well as an improved fossil record. This contribution will review current perspectives on the origin and early evolution of primates, paying particular attention to their phylogenetic (including cladistic relationships and character evolution) and environmental (including chronology, geography, and physical environments) contextualisation, before attempting an up-to-date ecomorphological synthesis of primate origins. © 2016 Anatomical Society.

  9. Dynamic Equivalent Modeling of a Grid-Tied Microgrid Based on Characteristic Model and Measurement Data

    Directory of Open Access Journals (Sweden)

    Changchun Cai

    2017-11-01

    Full Text Available Microgrids can significantly improve the utilization of distributed generation (DG and the reliability of the power supply. However, in the grid-tied operational mode, the interaction between the microgrid and the distribution network cannot be ignored. The paper proposes an equivalent modeling method for the microgrid under grid-tied mode based on a characteristic model. It can simplify the microgrid model in the numerical simulation of the distribution network. The proposed equivalent model can present the dynamic response of a microgrid but not miss any of its primary characteristics. The characteristic model is represented by a low-order time-varying differential equation with the same characteristics of the original microgrid system. During the modeling process, the voltage and the power exchanged between the microgrid and distribution network are collected as the training data for the identification of model parameters. A recursive damped least squares algorithm (RDLS is used for the parameter identification. A microgrid system containing different DGs is built to test the proposed modeling method in DIgSILENT, and the results show that the proposed dynamic equivalent modeling method is effective and the characteristic model can present the dynamic behaviors of the detailed model of a microgrid.

  10. The Recruitment Theory of Language Origins

    Science.gov (United States)

    Steels, Luc

    Tremendous progress has been made recently on the fascinating question of the origins and evolution of language (see e.g. (55), (7), (9), (31)). There is no widely accepted complete theory yet, but several proposals are on the table and observations and experiments are proceeding. This chapter focuses on the recruitment theory of language origins which we have been exploring for almost ten years now. This theory argues that language users recruit and try out different strategies for solving the task of communication and retain those that maximise communicative success and cognitive economy. Each strategy requires specific cognitive neural mechanisms, which in themselves serve a wide range of purposes and therefore may have evolved or could be learned independently of language.

  11. Epistemology of the origin of cancer: a new paradigm

    International Nuclear Information System (INIS)

    Brücher, Björn LDM; Jamall, Ijaz S

    2014-01-01

    Carcinogenesis is widely thought to originate from somatic mutations and an inhibition of growth suppressors, followed by cell proliferation, tissue invasion, and risk of metastasis. Fewer than 10% of all cancers are hereditary; the ratio in gastric (1%), colorectal (3-5%) and breast (8%) cancers is even less. Cancers caused by infection are thought to constitute some 15% of the non-hereditary cancers. Those remaining, 70 to 80%, are called “sporadic,” because they are essentially of unknown etiology. We propose a new paradigm for the origin of the majority of cancers. Our paradigm postulates that cancer originates following a sequence of events that include (1) a pathogenic stimulus (biological or chemical) followed by (2) chronic inflammation, from which develops (3) fibrosis with associated changes in the cellular microenvironment. From these changes a (4) pre-cancerous niche develops, which triggers the deployment of (5) a chronic stress escape strategy, and when this fails to resolve, (6) a transition of a normal cell to a cancer cell occurs. If we are correct, this paradigm would suggest that the majority of the findings in cancer genetics so far reported are either late events or are epiphenomena that occur after the appearance of the pre-cancerous niche. If, based on experimental and clinical findings presented here, this hypothesis is plausible, then the majority of findings in the genetics of cancer so far reported in the literature are late events or epiphenomena that could have occurred after the development of a PCN. Our model would make clear the need to establish preventive measures long before a cancer becomes clinically apparent. Future research should focus on the intermediate steps of our proposed sequence of events, which will enhance our understanding of the nature of carcinogenesis. Findings on inflammation and fibrosis would be given their warranted importance, with research in anticancer therapies focusing on suppressing the PCN state

  12. Structural properties of replication origins in yeast DNA sequences

    International Nuclear Information System (INIS)

    Cao Xiaoqin; Zeng Jia; Yan Hong

    2008-01-01

    Sequence-dependent DNA flexibility is an important structural property originating from the DNA 3D structure. In this paper, we investigate the DNA flexibility of the budding yeast (S. Cerevisiae) replication origins on a genome-wide scale using flexibility parameters from two different models, the trinucleotide and the tetranucleotide models. Based on analyzing average flexibility profiles of 270 replication origins, we find that yeast replication origins are significantly rigid compared with their surrounding genomic regions. To further understand the highly distinctive property of replication origins, we compare the flexibility patterns between yeast replication origins and promoters, and find that they both contain significantly rigid DNAs. Our results suggest that DNA flexibility is an important factor that helps proteins recognize and bind the target sites in order to initiate DNA replication. Inspired by the role of the rigid region in promoters, we speculate that the rigid replication origins may facilitate binding of proteins, including the origin recognition complex (ORC), Cdc6, Cdt1 and the MCM2-7 complex

  13. In the Beginning was a Mutualism - On the Origin of Translation

    Science.gov (United States)

    Vitas, Marko; Dobovišek, Andrej

    2018-04-01

    The origin of translation is critical for understanding the evolution of life, including the origins of life. The canonical genetic code is one of the most dominant aspects of life on this planet, while the origin of heredity is one of the key evolutionary transitions in living world. Why the translation apparatus evolved is one of the enduring mysteries of molecular biology. Assuming the hypothesis, that during the emergence of life evolution had to first involve autocatalytic systems which only subsequently acquired the capacity of genetic heredity, we propose and discuss possible mechanisms, basic aspects of the emergence and subsequent molecular evolution of translation and ribosomes, as well as enzymes as we know them today. It is possible, in this sense, to view the ribosome as a digital-to-analogue information converter. The proposed mechanism is based on the abilities and tendencies of short RNA and polypeptides to fold and to catalyse biochemical reactions. The proposed mechanism is in concordance with the hypothesis of a possible chemical co-evolution of RNA and proteins in the origin of the genetic code or even more generally at the early evolution of life on Earth. The possible abundance and availability of monomers at prebiotic conditions are considered in the mechanism. The hypothesis that early polypeptides were folding on the RNA scaffold is also considered and mutualism in molecular evolutionary development of RNA and peptides is favoured.

  14. Exploring the mediating role of trust in food products with Protected Designation of Origin. The case of “Jamón de Teruel”

    Directory of Open Access Journals (Sweden)

    Carmina Fandos-Herrera

    2016-03-01

    Full Text Available The growing concern about quality in food products has substantially increased the competitiveness of agro-food products that possess quality-system certifications compared to non-certificated products. This research focused on understanding how consumer trust is greater when agro-food products have a Protected Designation of Origin (PDO. In particular, we analyze whether the influence of consumers’ perceived quality of a PDO product has a direct effect on their perceived risk or whether this relationship is mediated by consumer trust, which can help us advance in the study of consumer behavior within the agro-food marketing discipline. Our findings obtained through the comparison of two models, the proposal and another rival, suggest that the initially proposed model present a better fit and explains the relationships better than the rival model, which highlights the essential role of consumer trust in explaining consumers’ perceived risk and their subsequent purchasing behavior. Consequently, managers should pay special attention to consumer trust because trust is the key mediating aspect which allows the incorporation of characteristics highly valued by consumers in food products like origin, tradition and production methods to reduce perceived risk.

  15. Exploring the mediating role of trust in food products with Protected Designation of Origin. The case of ´Jamón de Teruel

    Energy Technology Data Exchange (ETDEWEB)

    Fandos-Herrera, C.

    2016-11-01

    The growing concern about quality in food products has substantially increased the competitiveness of agro-food products that possess quality-system certifications compared to non-certificated products. This research focused on understanding how consumer trust is greater when agro-food products have a Protected Designation of Origin (PDO). In particular, we analyze whether the influence of consumers’ perceived quality of a PDO product has a direct effect on their perceived risk or whether this relationship is mediated by consumer trust, which can help us advance in the study of consumer behavior within the agro-food marketing discipline. Our findings obtained through the comparison of two models, the proposal and another rival, suggest that the initially proposed model present a better fit and explains the relationships better than the rival model, which highlights the essential role of consumer trust in explaining consumers’ perceived risk and their subsequent purchasing behavior. Consequently, managers should pay special attention to consumer trust because trust is the key mediating aspect which allows the incorporation of characteristics highly valued by consumers in food products like origin, tradition and production methods to reduce perceived risk. (Author)

  16. A modified Galam’s model for word-of-mouth information exchange

    Science.gov (United States)

    Ellero, Andrea; Fasano, Giovanni; Sorato, Annamaria

    2009-09-01

    In this paper we analyze the stochastic model proposed by Galam in [S. Galam, Modelling rumors: The no plane Pentagon French hoax case, Physica A 320 (2003), 571-580], for information spreading in a ‘word-of-mouth’ process among agents, based on a majority rule. Using the communications rules among agents defined in the above reference, we first perform simulations of the ‘word-of-mouth’ process and compare the results with the theoretical values predicted by Galam’s model. Some dissimilarities arise in particular when a small number of agents is considered. We find motivations for these dissimilarities and suggest some enhancements by introducing a new parameter dependent model. We propose a modified Galam’s scheme which is asymptotically coincident with the original model in the above reference. Furthermore, for relatively small values of the parameter, we provide a numerical experience proving that the modified model often outperforms the original one.

  17. A Taxonomy of Latent Structure Assumptions for Probability Matrix Decomposition Models.

    Science.gov (United States)

    Meulders, Michel; De Boeck, Paul; Van Mechelen, Iven

    2003-01-01

    Proposed a taxonomy of latent structure assumptions for probability matrix decomposition (PMD) that includes the original PMD model and a three-way extension of the multiple classification latent class model. Simulation study results show the usefulness of the taxonomy. (SLD)

  18. Daily air quality index forecasting with hybrid models: A case in China

    International Nuclear Information System (INIS)

    Zhu, Suling; Lian, Xiuyuan; Liu, Haixia; Hu, Jianming; Wang, Yuanyuan; Che, Jinxing

    2017-01-01

    Air quality is closely related to quality of life. Air pollution forecasting plays a vital role in air pollution warnings and controlling. However, it is difficult to attain accurate forecasts for air pollution indexes because the original data are non-stationary and chaotic. The existing forecasting methods, such as multiple linear models, autoregressive integrated moving average (ARIMA) and support vector regression (SVR), cannot fully capture the information from series of pollution indexes. Therefore, new effective techniques need to be proposed to forecast air pollution indexes. The main purpose of this research is to develop effective forecasting models for regional air quality indexes (AQI) to address the problems above and enhance forecasting accuracy. Therefore, two hybrid models (EMD-SVR-Hybrid and EMD-IMFs-Hybrid) are proposed to forecast AQI data. The main steps of the EMD-SVR-Hybrid model are as follows: the data preprocessing technique EMD (empirical mode decomposition) is utilized to sift the original AQI data to obtain one group of smoother IMFs (intrinsic mode functions) and a noise series, where the IMFs contain the important information (level, fluctuations and others) from the original AQI series. LS-SVR is applied to forecast the sum of the IMFs, and then, S-ARIMA (seasonal ARIMA) is employed to forecast the residual sequence of LS-SVR. In addition, EMD-IMFs-Hybrid first separately forecasts the IMFs via statistical models and sums the forecasting results of the IMFs as EMD-IMFs. Then, S-ARIMA is employed to forecast the residuals of EMD-IMFs. To certify the proposed hybrid model, AQI data from June 2014 to August 2015 collected from Xingtai in China are utilized as a test case to investigate the empirical research. In terms of some of the forecasting assessment measures, the AQI forecasting results of Xingtai show that the two proposed hybrid models are superior to ARIMA, SVR, GRNN, EMD-GRNN, Wavelet-GRNN and Wavelet-SVR. Therefore, the

  19. 77 FR 23490 - Agency Information Collection Activities: Country of Origin Marking Requirements for Containers...

    Science.gov (United States)

    2012-04-19

    ... Activities: Country of Origin Marking Requirements for Containers or Holders AGENCY: U.S. Customs and Border... of Origin Marking Requirements for Containers or Holders. This is a proposed extension of an... Requirements for Containers or Holders. [[Page 23491

  20. A Method of Upgrading a Hydrostatic Model to a Nonhydrostatic Model

    Directory of Open Access Journals (Sweden)

    Chi-Sann Liou

    2009-01-01

    Full Text Available As the sigma-p coordinate under hydrostatic approximation can be interpreted as the mass coordinate with out the hydro static approximation, we propose a method that up grades a hydro static model to a nonhydrostatic model with relatively less effort. The method adds to the primitive equations the extra terms omitted by the hydro static approximation and two prognostic equations for vertical speed w and nonhydrostatic part pres sure p'. With properly formulated governing equations, at each time step, the dynamic part of the model is first integrated as that for the original hydro static model and then nonhydrostatic contributions are added as corrections to the hydro static solutions. In applying physical parameterizations after the dynamic part integration, all physics pack ages of the original hydro static model can be directly used in the nonhydrostatic model, since the up graded nonhydrostatic model shares the same vertical coordinates with the original hydro static model. In this way, the majority codes of the nonhydrostatic model come from the original hydro static model. The extra codes are only needed for the calculation additional to the primitive equations. In order to handle sound waves, we use smaller time steps in the nonhydrostatic part dynamic time integration with a split-explicit scheme for horizontal momentum and temperature and a semi-implicit scheme for w and p'. Simulations of 2-dimensional mountain waves and density flows associated with a cold bubble have been used to test the method. The idealized case tests demonstrate that the pro posed method realistically simulates the nonhydrostatic effects on different atmospheric circulations that are revealed in the oretical solutions and simulations from other nonhydrostatic models. This method can be used in upgrading any global or mesoscale models from a hydrostatic to nonhydrostatic model.

  1. Discrimination of Geographical Origin of Asian Garlic Using Isotopic and Chemical Datasets under Stepwise Principal Component Analysis.

    Science.gov (United States)

    Liu, Tsang-Sen; Lin, Jhen-Nan; Peng, Tsung-Ren

    2018-01-16

    Isotopic compositions of δ 2 H, δ 18 O, δ 13 C, and δ 15 N and concentrations of 22 trace elements from garlic samples were analyzed and processed with stepwise principal component analysis (PCA) to discriminate garlic's country of origin among Asian regions including South Korea, Vietnam, Taiwan, and China. Results indicate that there is no single trace-element concentration or isotopic composition that can accomplish the study's purpose and the stepwise PCA approach proposed does allow for discrimination between countries on a regional basis. Sequentially, Step-1 PCA distinguishes garlic's country of origin among Taiwanese, South Korean, and Vietnamese samples; Step-2 PCA discriminates Chinese garlic from South Korean garlic; and Step-3 and Step-4 PCA, Chinese garlic from Vietnamese garlic. In model tests, countries of origin of all audit samples were correctly discriminated by stepwise PCA. Consequently, this study demonstrates that stepwise PCA as applied is a simple and effective approach to discriminating country of origin among Asian garlics. © 2018 American Academy of Forensic Sciences.

  2. Stress, autonomic imbalance, and the prediction of metabolic risk: A model and a proposal for research.

    Science.gov (United States)

    Wulsin, Lawson; Herman, James; Thayer, Julian F

    2018-03-01

    Devising novel prevention strategies for metabolic disorders will depend in part on the careful elucidation of the common pathways for developing metabolic risks. The neurovisceral integration model has proposed that autonomic imbalance plays an important role in the pathway from acute and chronic stress to cardiovascular disease. Though generally overlooked by clinicians, autonomic imbalance (sympathetic overactivity and/or parasympathetic underactivity) can be measured and modified by methods that are available in primary care. This review applies the neurovisceral integration concept to the clinical setting by proposing that autonomic imbalance plays a primary role in the development of metabolic risks. We present a testable model, a systematic review of the evidence in support of autonomic imbalance as a predictor for metabolic risks, and specific approaches to test this model as a guide to future research on the role of stress in metabolic disorders. We propose that autonomic imbalance deserves consideration by researchers, clinicians, and policymakers as a target for early interventions to prevent metabolic disorders. Published by Elsevier Ltd.

  3. A proposed strategy for the validation of ground-water flow and solute transport models

    International Nuclear Information System (INIS)

    Davis, P.A.; Goodrich, M.T.

    1991-01-01

    Ground-water flow and transport models can be thought of as a combination of conceptual and mathematical models and the data that characterize a given system. The judgment of the validity or invalidity of a model depends both on the adequacy of the data and the model structure (i.e., the conceptual and mathematical model). This report proposes a validation strategy for testing both components independently. The strategy is based on the philosophy that a model cannot be proven valid, only invalid or not invalid. In addition, the authors believe that a model should not be judged in absence of its intended purpose. Hence, a flow and transport model may be invalid for one purpose but not invalid for another. 9 refs

  4. The human dark side: evolutionary psychology and original sin.

    Science.gov (United States)

    Lee, Joseph; Theol, M

    2014-04-01

    Human nature has a dark side, something important to religions. Evolutionary psychology has been used to illuminate the human shadow side, although as a discipline it has attracted criticism. This article seeks to examine the evolutionary psychology's understanding of human nature and to propose an unexpected dialog with an enduring account of human evil known as original sin. Two cases are briefly considered: murder and rape. To further the exchange, numerous theoretical and methodological criticisms and replies of evolutionary psychology are explored jointly with original sin. Evolutionary psychology can partner with original sin since they share some theoretical likenesses and together they offer insights into the nature of what it means to be human.

  5. ORIGIN: Metal Creation and Evolution from the Cosmic Dawn

    DEFF Research Database (Denmark)

    Herder, J. W. den; Piro, L.; Ohashi, T.

    2011-01-01

    , and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to the early Universe ORIGIN will use Gamma......ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z=10...

  6. Gamma-ray astronomy and cosmic-ray origin theory

    International Nuclear Information System (INIS)

    Ginzburg, V.L.

    1973-01-01

    A theory of the origin of cosmic radiation is discussed in light of the advances made in gamma-ray astronomy. Arguments against metagalactic models for the origin of cosmic rays are emphasized. (U.S.)

  7. Increasing Prediction the Original Final Year Project of Student Using Genetic Algorithm

    Science.gov (United States)

    Saragih, Rijois Iboy Erwin; Turnip, Mardi; Sitanggang, Delima; Aritonang, Mendarissan; Harianja, Eva

    2018-04-01

    Final year project is very important forgraduation study of a student. Unfortunately, many students are not seriouslydidtheir final projects. Many of studentsask for someone to do it for them. In this paper, an application of genetic algorithms to predict the original final year project of a studentis proposed. In the simulation, the data of the final project for the last 5 years is collected. The genetic algorithm has several operators namely population, selection, crossover, and mutation. The result suggest that genetic algorithm can do better prediction than other comparable model. Experimental results of predicting showed that 70% was more accurate than the previous researched.

  8. Islet Cells Serve as Cells of Origin of Pancreatic Gastrin-Positive Endocrine Tumors

    DEFF Research Database (Denmark)

    Bonnavion, Rémy; Teinturier, Romain; Jaafar, Rami

    2015-01-01

    The cells of origin of pancreatic gastrinomas remain an enigma, since no gastrin-expressing cells are found in the normal adult pancreas. It was proposed that the cellular origin of pancreatic gastrinomas may come from either the pancreatic cells themselves or gastrin-expressing cells which have ...

  9. Origin of family symmetries

    International Nuclear Information System (INIS)

    Nilles, Hans Peter

    2012-04-01

    Discrete (family) symmetries might play an important role in models of elementary particle physics. We discuss the origin of such symmetries in the framework of consistent ultraviolet completions of the standard model in field and string theory. The symmetries can arise due to special geometrical properties of extra compact dimensions and the localization of fields in this geometrical landscape. We also comment on anomaly constraints for discrete symmetries.

  10. Origin of family symmetries

    Energy Technology Data Exchange (ETDEWEB)

    Nilles, Hans Peter [Bonn Univ. (Germany). Bethe Center for Theoretical Physics; Bonn Univ. (Germany). Physikalisches Inst.; Ratz, Michael [Technische Univ. Muenchen, Garching (Germany). Physik-Department; Vaudrevange, Patrick K.S. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2012-04-15

    Discrete (family) symmetries might play an important role in models of elementary particle physics. We discuss the origin of such symmetries in the framework of consistent ultraviolet completions of the standard model in field and string theory. The symmetries can arise due to special geometrical properties of extra compact dimensions and the localization of fields in this geometrical landscape. We also comment on anomaly constraints for discrete symmetries.

  11. Second generation diffusion model of interacting gravity waves on the surface of deep fluid

    Directory of Open Access Journals (Sweden)

    A. Pushkarev

    2004-01-01

    Full Text Available We propose a second generation phenomenological model for nonlinear interaction of gravity waves on the surface of deep water. This model takes into account the effects of non-locality of the original Hasselmann diffusion equation still preserving important properties of the first generation model: physically consistent scaling, adherence to conservation laws and the existence of Kolmogorov-Zakharov solutions. Numerical comparison of both models with the original Hasselmann equation shows that the second generation models improves the angular distribution in the evolving wave energy spectrum.

  12. An automation of design and modelling tasks in NX Siemens environment with original software - generator module

    Science.gov (United States)

    Zbiciak, M.; Grabowik, C.; Janik, W.

    2015-11-01

    Nowadays the design constructional process is almost exclusively aided with CAD/CAE/CAM systems. It is evaluated that nearly 80% of design activities have a routine nature. These design routine tasks are highly susceptible to automation. Design automation is usually made with API tools which allow building original software responsible for adding different engineering activities. In this paper the original software worked out in order to automate engineering tasks at the stage of a product geometrical shape design is presented. The elaborated software works exclusively in NX Siemens CAD/CAM/CAE environment and was prepared in Microsoft Visual Studio with application of the .NET technology and NX SNAP library. The software functionality allows designing and modelling of spur and helicoidal involute gears. Moreover, it is possible to estimate relative manufacturing costs. With the Generator module it is possible to design and model both standard and non-standard gear wheels. The main advantage of the model generated in such a way is its better representation of an involute curve in comparison to those which are drawn in specialized standard CAD systems tools. It comes from fact that usually in CAD systems an involute curve is drawn by 3 points that respond to points located on the addendum circle, the reference diameter of a gear and the base circle respectively. In the Generator module the involute curve is drawn by 11 involute points which are located on and upper the base and the addendum circles therefore 3D gear wheels models are highly accurate. Application of the Generator module makes the modelling process very rapid so that the gear wheel modelling time is reduced to several seconds. During the conducted research the analysis of differences between standard 3 points and 11 points involutes was made. The results and conclusions drawn upon analysis are shown in details.

  13. The ERICAM model: a proposal for amelioration of nuclear liability by funding on the capital markets

    International Nuclear Information System (INIS)

    Tyran, J.R.

    1995-01-01

    The ERICAM model (Environmental Risk Internalization through Capital Markets) includes the capital markets as a source contributing to the coverage of risks due to nuclear activites, thus enhancing the effectiveness and functions of the nuclear liability law. The model proposed will allow higher amounts for compensation and will increase financial security, flow of information, and efficient use of resources. The implementation of the model can be achieved on the financing side by issuing Nuke bonds, linking accident-specific options to government bonds. This will essentially increase the risk coverage compared to present means, and will be a pin-pointed addition to the existing layer system. There are three institutions proposed to act as mediators in the implementation of the model: A government authority to supervise the trade in Nuke bonds. Risk-bearing associations in oder to enhance the model's efficiency, and to reduce transaction costs. Rating agencies that will reduce the expenditure for information. (orig./HP) [de

  14. Characteristic fingerprint based on gingerol derivative analysis for discrimination of ginger (Zingiber officinale) according to geographical origin using HPLC-DAD combined with chemometrics.

    Science.gov (United States)

    Yudthavorasit, Soparat; Wongravee, Kanet; Leepipatpiboon, Natchanun

    2014-09-01

    Chromatographic fingerprints of gingers from five different ginger-producing countries (China, India, Malaysia, Thailand and Vietnam) were newly established to discriminate the origin of ginger. The pungent bioactive principles of ginger, gingerols and six other gingerol-related compounds were determined and identified. Their variations in HPLC profiles create the characteristic pattern of each origin by employing similarity analysis, hierarchical cluster analysis (HCA), principal component analysis (PCA) and linear discriminant analysis (LDA). As results, the ginger profiles tended to be grouped and separated on the basis of the geographical closeness of the countries of origin. An effective mathematical model with high predictive ability was obtained and chemical markers for each origin were also identified as the characteristic active compounds to differentiate the ginger origin. The proposed method is useful for quality control of ginger in case of origin labelling and to assess food authenticity issues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. A proposed agglomerate model for oxygen reduction in the catalyst layer of proton exchange membrane fuel cells

    International Nuclear Information System (INIS)

    Zhang, Xiaoxian; Gao, Yuan; Ostadi, Hossein; Jiang, Kyle; Chen, Rui

    2014-01-01

    Highlights: • We developed a new agglomerate model to describe oxygen reduction reaction. • We showed how to calculate the model parameters from catalyst layer structure. • We verified the agglomerate model. - Abstract: Oxygen diffusion and reduction in the catalyst layer of PEM fuel cell is an important process in fuel cell modelling, but models able to link the reduction rate to catalyst-layer structure are lack; this paper makes such an effort. We first link the average reduction rate over the agglomerate within a catalyst layer to a probability that an oxygen molecule, which is initially on the agglomerate surface, will enter and remain in the agglomerate at any time in the absence of any electrochemical reaction. We then propose a method to directly calculate distribution function of this probability and apply it to two catalyst layers with contrasting structures. A formula is proposed to describe these calculated distribution functions, from which the agglomerate model is derived. The model has two parameters and both can be independently calculated from catalyst layer structures. We verify the model by first showing that it is an improvement and able to reproduce what the spherical model describes, and then testing it against the average oxygen reductions directly calculated from pore-scale simulations of oxygen diffusion and reaction in the two catalyst layers. The proposed model is simple, but significant as it links the average oxygen reduction to catalyst layer structures, and its two parameters can be directly calculated rather than by calibration

  16. The origin of Venusian channels: Modelling of thermal erosion by lava

    Science.gov (United States)

    Bussey, D. B. J.; Sorensen, S-A.; Guest, J. E.

    1993-01-01

    Magellan imagery has revealed that channels, apparently volcanic in origin, are abundant on the surface of Venus. There has been much debate about the origin of these channels. Are they the result of erosional (either thermal or mechanical) or constructional processes? A common characteristic of the simple sinuous channels is that they show evidence of erosion near their source and then become purely constructional, forming levees and in some cases roofing over completely. One method of showing that thermal erosion is capable of producing the type of channels seen is to use computer modeling incorporating the physical conditions on Venus and the physical characteristics of the different types of lava that may have been erupted. It is possible to calculate, relatively easily, two channel parameters. The first is the erosion rate, which combined with eruption duration, gives depth. The second is for how long after leaving the source the erupted lava will continue to be capable of thermal erosion before constructional processes dominate. Making assumptions about the rheology of the lava (e.g., assume it behaves as a Bingham plastic) along with the slope angle yields a flow velocity and therefore a distance over which thermal erosion will take place. Due to the resolution (both vertical and horizontal) of the Magellan altimetric data, the distance from the source that the channel is erosional can be much more accurately measured than the depth of the channel. This will remain the case until stereo imagery becomes available for large areas of the planet.

  17. PROPOSED SUITE OF MODELS FOR ESTIMATING DOSE RESULTING FROM EXPOSURES BY THE DERMAL ROUTE

    Science.gov (United States)

    Recent risk assessment guidance emphasizes consideration of mechanistic factors for influencing disposition of a toxicant. To incorporate mechanistic information into risk assessment, a suite of models is proposed for use in characterizing and quantifying dosimetry of toxic age...

  18. Proposal for a model for competitiveness analysis in environmental sustainability in automotive segment companies

    Directory of Open Access Journals (Sweden)

    Luís Henrique Rodrigues

    2018-06-01

    Full Text Available The competitive landscape for companies has been changing over time, featuring an increase in competitiveness in cost, quality, reliability, agility and more recently by a concern for environmental and social factors. This work aims to propose an exploratory analysis model to evaluate companies’ sustainability competitiveness. The model proposes the grouping of companies into clusters, ranking them according to the adoption of lean manufacturing practices, environmental management and human resources, and allocating them into quadrants according to the higher or lower production of waste in their manufacturing processes. The adherence to the model is made with a sample of automotive segment companies (auto parts and motor vehicle manufacturers. The work is classified as one of a practical nature, exploratory, qualitative, and using the survey method. The conclusion that 37.5% of auto parts companies are grouped into clusters that lead to the reduction of waste, with practices in lean manufacturing and environmental management which adjust to competitive factors in the sustainability of motor vehicle manufacturers, is noteworthy.

  19. Chaotic System Identification Based on a Fuzzy Wiener Model with Particle Swarm Optimization

    International Nuclear Information System (INIS)

    Yong, Li; Ying-Gan, Tang

    2010-01-01

    A fuzzy Wiener model is proposed to identify chaotic systems. The proposed fuzzy Wiener model consists of two parts, one is a linear dynamic subsystem and the other is a static nonlinear part, which is represented by the Takagi–Sugeno fuzzy model. Identification of chaotic systems is converted to find optimal parameters of the fuzzy Wiener model by minimizing the state error between the original chaotic system and the fuzzy Wiener model. Particle swarm optimization algorithm, a global optimizer, is used to search the optimal parameter of the fuzzy Wiener model. The proposed method can identify the parameters of the linear part and nonlinear part simultaneously. Numerical simulations for Henón and Lozi chaotic system identification show the effectiveness of the proposed method

  20. Proposed revision to the taxonomy of the genus Pestivirus, family Flaviviridae

    OpenAIRE

    Smith, Donald B.; Meyers, Gregor; Bukh, Jens; Gould, Ernest A.; Monath, Thomas; Muerhoff, A. Scott; Pletnev, Alexander; Rico-Hesse, Rebecca; Stapleton, Jack T.; Simmonds, Peter; Becher, Paul

    2017-01-01

    We propose the creation of seven new species in the genus Pestivirus (family Flaviviridae) in addition to the four existing species, and naming species in a host-independent manner using the format Pestivirus X. Only the virus species names would change; virus isolates would still be referred to by their original names. The original species would be re-designated as Pestivirus A (original designation Bovine viral diarrhea virus 1), Pestivirus B (Bovine viral diarrhea virus 2), Pestivirus C (C...

  1. T-S Fuzzy Modelling and H∞ Attitude Control for Hypersonic Gliding Vehicles

    Directory of Open Access Journals (Sweden)

    Weidong Zhang

    2017-01-01

    Full Text Available This paper addresses the T-S fuzzy modelling and H∞ attitude control in three channels for hypersonic gliding vehicles (HGVs. First, the control-oriented affine nonlinear model has been established which is transformed from the reentry dynamics. Then, based on Taylor’s expansion approach and the fuzzy linearization approach, the homogeneous T-S local modelling technique for HGVs is proposed. Given the approximation accuracy and controller design complexity, appropriate fuzzy premise variables and operating points of interest are selected to construct the T-S homogeneous submodels. With so-called fuzzy blending, the original plant is transformed into the overall T-S fuzzy model with disturbance. By utilizing Lyapunov functional approach, a state feedback fuzzy controller has been designed based on relaxed linear matrix inequality (LMI conditions to stable the original plants with a prescribed H∞ performance of disturbance. Finally, numerical simulations are performed to demonstrate the effectiveness of the proposed H∞ T-S fuzzy controller for the original attitude dynamics; the superiority of the designed T-S fuzzy controller compared with other local controllers based on the constructed fuzzy model is shown as well.

  2. Proposed Core Competencies and Empirical Validation Procedure in Competency Modeling: Confirmation and Classification.

    Science.gov (United States)

    Baczyńska, Anna K; Rowiński, Tomasz; Cybis, Natalia

    2016-01-01

    Competency models provide insight into key skills which are common to many positions in an organization. Moreover, there is a range of competencies that is used by many companies. Researchers have developed core competency terminology to underline their cross-organizational value. The article presents a theoretical model of core competencies consisting of two main higher-order competencies called performance and entrepreneurship. Each of them consists of three elements: the performance competency includes cooperation, organization of work and goal orientation, while entrepreneurship includes innovativeness, calculated risk-taking and pro-activeness. However, there is lack of empirical validation of competency concepts in organizations and this would seem crucial for obtaining reliable results from organizational research. We propose a two-step empirical validation procedure: (1) confirmation factor analysis, and (2) classification of employees. The sample consisted of 636 respondents (M = 44.5; SD = 15.1). Participants were administered a questionnaire developed for the study purpose. The reliability, measured by Cronbach's alpha, ranged from 0.60 to 0.83 for six scales. Next, we tested the model using a confirmatory factor analysis. The two separate, single models of performance and entrepreneurial orientations fit quite well to the data, while a complex model based on the two single concepts needs further research. In the classification of employees based on the two higher order competencies we obtained four main groups of employees. Their profiles relate to those found in the literature, including so-called niche finders and top performers. Some proposal for organizations is discussed.

  3. Simulations of living cell origins using a cellular automata model.

    Science.gov (United States)

    Ishida, Takeshi

    2014-04-01

    Understanding the generalized mechanisms of cell self-assembly is fundamental for applications in various fields, such as mass producing molecular machines in nanotechnology. Thus, the details of real cellular reaction networks and the necessary conditions for self-organized cells must be elucidated. We constructed a 2-dimensional cellular automata model to investigate the emergence of biological cell formation, which incorporated a looped membrane and a membrane-bound information system (akin to a genetic code and gene expression system). In particular, with an artificial reaction system coupled with a thermal system, the simultaneous formation of a looped membrane and an inner reaction process resulted in a more stable structure. These double structures inspired the primitive biological cell formation process from chemical evolution stage. With a model to simulate cellular self-organization in a 2-dimensional cellular automata model, 3 phenomena could be realized: (1) an inner reaction system developed as an information carrier precursor (akin to DNA); (2) a cell border emerged (akin to a cell membrane); and (3) these cell structures could divide into 2. This double-structured cell was considered to be a primary biological cell. The outer loop evolved toward a lipid bilayer membrane, and inner polymeric particles evolved toward precursor information carriers (evolved toward DNA). This model did not completely clarify all the necessary and sufficient conditions for biological cell self-organization. Further, our virtual cells remained unstable and fragile. However, the "garbage bag model" of Dyson proposed that the first living cells were deficient; thus, it would be reasonable that the earliest cells were more unstable and fragile than the simplest current unicellular organisms.

  4. Business model dynamics and innovation

    DEFF Research Database (Denmark)

    Cavalcante, Sergio Andre; Kesting, Peter; Ulhøi, John Parm

    2011-01-01

    the impact of specific changes to a firm's business model. Such a tool would be particularly useful in identifying path dependencies and resistance at the process level, and would therefore allow a firm's management to take focused action on this in advance. Originality/value – The paper makes two main...... and specifies four different types of business model change: business model creation, extension, revision, and termination. Each type of business model change is associated with specific challenges. Practical implications – The proposed typology can serve as a basis for developing a management tool to evaluate......Purpose – This paper aims to discuss the need to dynamize the existing conceptualization of business model, and proposes a new typology to distinguish different types of business model change. Design/methodology/approach – The paper integrates basic insights of innovation, business process...

  5. Origin and outcome of multiple pregnancies in Bern, Switzerland, 1995-2006 and the current proposal of the Swiss parliament to revise the Swiss law of reproductive medicine: Switzerland quo vadis?

    Science.gov (United States)

    Wunder, Dorothea; Neurohr, Eva-Maria; Faouzi, Mohamed; Birkhäuser, Martin H

    2013-09-19

    Infertility treatments are a major source of the increase in multiple pregnancies (MPs). The aims of the present study were (1.) to investigate the origin and maternal/neonatal outcomes of MP and (2.) to review the different measures that can be adopted to reduce these serious complications. The study included all women with multiple births between 1 January 1995 and 31 December 2006 at the University Hospital of Bern, Switzerland. The outcomes associated with the various origins of MP (natural conception, ovarian stimulation [OS]--in-vitro fertilisation [IVF-ICSI]) were analysed using a multinomial logistic regression model. An analysis of the Swiss law on reproductive medicine and its current proposed revision, as well as a literature review using Pubmed, was carried out. A total of 592 MP were registered, 91% (n = 537) resulted in live births. There was significantly more neonatal/maternal morbidity in MP after OS compared with natural conception and even with the IVF-ICSI group. With a policy of elective single embryo transfer (eSET), twin rates after IVF-ICSI can be reduced to <5% and triplets to <1%. After OS, more triplets are found and the outcome of MP is worse. MP is known to be associated with morbidity, mortality, and economic and social risks. To counteract these complications (1.) better training for physicians performing OS should be encouraged and (2.) the Swiss law on reproductive medicine needs to be changed, with the introduction of eSET policies. This would lead to a dramatic decrease in neonatal and maternal morbidity/mortality as well as significant cost reductions for the Swiss healthcare system.

  6. Bovine origin Staphylococcus aureus: A new zoonotic agent?

    Science.gov (United States)

    Rao, Relangi Tulasi; Jayakumar, Kannan; Kumar, Pavitra

    2017-10-01

    The study aimed to assess the nature of animal origin Staphylococcus aureus strains. The study has zoonotic importance and aimed to compare virulence between two different hosts, i.e., bovine and ovine origin. Conventional polymerase chain reaction-based methods used for the characterization of S. aureus strains and chick embryo model employed for the assessment of virulence capacity of strains. All statistical tests carried on R program, version 3.0.4. After initial screening and molecular characterization of the prevalence of S. aureus found to be 42.62% in bovine origin samples and 28.35% among ovine origin samples. Meanwhile, the methicillin-resistant S. aureus prevalence is found to be meager in both the hosts. Among the samples, only 6.8% isolates tested positive for methicillin resistance. The biofilm formation quantified and the variation compared among the host. A Welch two-sample t -test found to be statistically significant, t=2.3179, df=28.103, and p=0.02795. Chicken embryo model found effective to test the pathogenicity of the strains. The study helped to conclude healthy bovines can act as S. aureus reservoirs. Bovine origin S. aureus strains are more virulent than ovine origin strains. Bovine origin strains have high probability to become zoonotic pathogen. Further, gene knock out studies may be conducted to conclude zoonocity of the bovine origin strains.

  7. 3D implicit modeling of the Sishen Mine: new resolution of the geometry and origin of Fe mineralization

    Science.gov (United States)

    Stoch, B.; Anthonissen, C. J.; McCall, M.-J.; Basson, I. J.; Deacon, J.; Cloete, E.; Botha, J.; Britz, J.; Strydom, M.; Nel, D.; Bester, M.

    2017-12-01

    The Sishen deposit is one of the largest iron ore concentrations in current production. Hematite mineralization occurs along a strike length of 14 km, with a width of 3.2 km and a maximum vertical extent of 400 m below the original surface. The 986-Mt reserve incorporates a suite of individual orebodies, beneath a locally preserved tectonized unconformity, with a wide range of geometries, depths, and orientations. Fully constrained, implicit 3D modeling of the entire mining volume (> 70 km3), was undertaken to the original, pre-mining topography. The model incorporates 5287 mapping points and > 21,000 drillholes and provides exceptional insight into the original configuration of ore and its relationship to contacts, unconformities, and structures in the enclosing country rock. The bulk of ore occurs to the west of a strike-extensive, partially inverted normal fault (Sloep Fault), within an asymmetrical synclinal structure on its western flank. This linear, N-S distribution of deep, thick ore is punctuated by palaeosinkholes, wherein base-of-ore dips of greater than 45°, are concentrically arranged. Localized ore volumes also occur along faults and in fault-bounded, downthrown blocks, to the north of NW-SE- and NE-SW-trending strike-slip faults that show relatively minor uplift to the south, probably due to the Lomanian Namaqua-Natal Orogeny. The revised model demonstrates the proximity of ore to a tectonized unconformity and highlights the structural control on ore volumes, implying that Fe mineralization at Sishen cannot be exclusively attributed to supergene enrichment and concentric palaeosinkhole formation.

  8. Analysis of uses and competitions of water resources or an original dissemination strategy of hydrological modelling results of an EU project ?

    Science.gov (United States)

    La Jeunesse, Isabelle; Fustec, Klervi; Larrue, Corinne; Trottier, Julie

    2010-05-01

    We propose to address the question of security threats through an analysis of water uses and competitions in the current situation, on one hand, and in conditions of climate change, on the other hand, in order to have an operational dissemination of hydrological modelling results. This will be carried out for each case study of the EU project CLIMB (7th EU FP). In this particular case, climate change impacts are to be considered in relation with water uses and rivalries. Taking them into account while involving stakeholders should allow us to have a deep impact on water uses regulation under conditions of climate change. The originality of this methodology, the first objective of which within the project is to disseminate project results and interact with stakeholders, is to use the dissemination phase as a means of involving stakeholder knowledge concerning water uses and competitions. The idea is to let the stakeholders identify themselves, in each case study, by means of interactive methods, the impact of the change of hydrological regime on their own water uses and competitions. We propose to use a real "bottom-up" strategy to assess the potential water uses and rivalries in the context of water scarcity (or flood) due to climate change. Such an approach will allow us to evaluate the risk of an increase in water rivalries and threats to security following climate change impacts scenarios at the river basin scale.

  9. Power flow prediction in vibrating systems via model reduction

    Science.gov (United States)

    Li, Xianhui

    This dissertation focuses on power flow prediction in vibrating systems. Reduced order models (ROMs) are built based on rational Krylov model reduction which preserve power flow information in the original systems over a specified frequency band. Stiffness and mass matrices of the ROMs are obtained by projecting the original system matrices onto the subspaces spanned by forced responses. A matrix-free algorithm is designed to construct ROMs directly from the power quantities at selected interpolation frequencies. Strategies for parallel implementation of the algorithm via message passing interface are proposed. The quality of ROMs is iteratively refined according to the error estimate based on residual norms. Band capacity is proposed to provide a priori estimate of the sizes of good quality ROMs. Frequency averaging is recast as ensemble averaging and Cauchy distribution is used to simplify the computation. Besides model reduction for deterministic systems, details of constructing ROMs for parametric and nonparametric random systems are also presented. Case studies have been conducted on testbeds from Harwell-Boeing collections. Input and coupling power flow are computed for the original systems and the ROMs. Good agreement is observed in all cases.

  10. Pre-glow phenomenon origin and its scaling for ECRIS

    International Nuclear Information System (INIS)

    Izotov, I.; Sidorov, A.; Skalyga, V.; Zorin, V.

    2012-01-01

    Pre-glow is the multi-charged ion current burst that may occur at the beginning of the beam pulse. Pre-glow effect investigation is one of topical directions of ECR ion sources development at present. Pre-glow is of interest for efficient short-pulsed multicharged ion source creation. Particularly, such source of intense beams of short living radioactive isotopes multi-charged ions is one of key elements in 'Beta-Beam' European project. The use of Pre-glow-generating regime of an ECRIS operation is a promising way of pulsed high-intense multi-charged ion beams production with much shorter edges in comparison with usual operation regime. Numerical simulations made with the updated theoretical model allow authors to propose more physical and intuitive explanations of Pre-glow phenomenon origins. The obtained dependences of Pre-glow characteristics on experimental conditions offer a scaling for a wide range of ECRIS. The propose scaling demonstrates that an ECR source with plasma heating by radiation at frequency of 37 GHz and higher seems to be the most effective in terms of currents, pre-glow intensity and mean ion charge. The paper is followed by the slides of the presentation

  11. Mathematical toy model inspired by the problem of the adaptive origins of the sexual orientation continuum

    Science.gov (United States)

    Skinner, Brian

    2016-09-01

    Same-sex sexual behaviour is ubiquitous in the animal kingdom, but its adaptive origins remain a prominent puzzle. Here, I suggest the possibility that same-sex sexual behaviour arises as a consequence of the competition between an evolutionary drive for a wide diversity in traits, which improves the adaptability of a population, and a drive for sexual dichotomization of traits, which promotes opposite-sex attraction and increases the rate of reproduction. This trade-off is explored via a simple mathematical `toy model'. The model exhibits a number of interesting features and suggests a simple mathematical form for describing the sexual orientation continuum.

  12. Proposal for intake model for workers at IPEN-CNEN/SP who handle 131 I

    International Nuclear Information System (INIS)

    Todo, A.S.; Potiens Junior, A.J.; Gaburo, J.C.; Sanches, M.P.; Oliveira, E.M.

    1997-01-01

    The intake model for the two groups of workers at IPEN-CNEN/SP is presented. They handle iodine compounds during the processing of irradiated targets and at labeling of radiopharmaceutical compounds. The intake model for the workers are proposed from the knowledge of the activities carried out in the plant and the internal monitoring program of the workers. In this study, the intake is considered to be taken uniformly during the days of major activities carried out by the workers. In practice, the application of this model has be shown suitable, for the studied groups

  13. Knowledge Management Implementation at the Women’s Branch of the Institute of Public Administration in Saudi Arabia: A Proposed Model

    Directory of Open Access Journals (Sweden)

    Eiman Saud Abokhodiar

    2014-05-01

    Full Text Available This article aims to introduce a proposed model of knowledge management implementation at the Women’s Branch of the Institute of Public Administration (WIPA. The model was built after a review and analysis of literature related to knowledge management implementation in higher education institutions. The research includes three sections. The first section deals with a theoretical framework of knowledge management, including a knowledge management definition, components of knowledge management systems, an academic knowledge framework, an organizational knowledge framework, and processes of knowledge management. The second section reviews and discusses the proposed model of knowledge management implementation at WIPA. Finally, the article concludes with a discussion of the success factors and expected barriers to the proposed model.

  14. The Natural Origins of Content

    DEFF Research Database (Denmark)

    Hutto, Daniel; Satne, Glenda Lucila

    2015-01-01

    to be reconceived in terms of explaining the natural origins of content. Second, the pivotal assumption that intentionality is always and everywhere contentful must be abandoned. Reviving and updating Haugeland’s baseball analogy in the light of these changes, we propose ways of redirecting the efforts of players...... on each base of his intentionality All-Star team, enabling them to start functioning effectively as a team. Only then is it likely that they will finally get their innings and maybe, just maybe, even win the game....

  15. Corporate Social Responsibility And Islamic Business Organizations: A Proposed Model

    Directory of Open Access Journals (Sweden)

    Rusnah Muhamad

    2008-01-01

    Full Text Available The issue of corporate social responsibility (CSR has been of growing concern among business communities in recent years. Various corporate leaders maintain that business is considered to contribute fully to the society if it is effi cient, profi table and socially responsible. Islam is considered as addin (a way of life, thus, providing comprehensive guidelines in every aspects of the believers’ life. It is the aim of this paper to propose an Islamic model of corporate social responsibility based on human relationships with the God (hablun min’Allah; with other fellow human being (hablun min’an-nas and with the environment.Keywords : Corporate Social Responsibility, Islamic Business Organization

  16. Rate turnover in mechano-catalytic coupling: A model and its microscopic origin

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Mahua; Grazioli, Gianmarc; Andricioaei, Ioan, E-mail: andricio@uci.edu [Department of Chemistry, University of California, Irvine, California 92697 (United States)

    2015-07-28

    A novel aspect in the area of mechano-chemistry concerns the effect of external forces on enzyme activity, i.e., the existence of mechano-catalytic coupling. Recent experiments on enzyme-catalyzed disulphide bond reduction in proteins under the effect of a force applied on the termini of the protein substrate reveal an unexpected biphasic force dependence for the bond cleavage rate. Here, using atomistic molecular dynamics simulations combined with Smoluchowski theory, we propose a model for this behavior. For a broad range of forces and systems, the model reproduces the experimentally observed rates by solving a reaction-diffusion equation for a “protein coordinate” diffusing in a force-dependent effective potential. The atomistic simulations are used to compute, from first principles, the parameters of the model via a quasiharmonic analysis. Additionally, the simulations are also used to provide details about the microscopic degrees of freedom that are important for the underlying mechano-catalysis.

  17. Rate turnover in mechano-catalytic coupling: A model and its microscopic origin

    International Nuclear Information System (INIS)

    Roy, Mahua; Grazioli, Gianmarc; Andricioaei, Ioan

    2015-01-01

    A novel aspect in the area of mechano-chemistry concerns the effect of external forces on enzyme activity, i.e., the existence of mechano-catalytic coupling. Recent experiments on enzyme-catalyzed disulphide bond reduction in proteins under the effect of a force applied on the termini of the protein substrate reveal an unexpected biphasic force dependence for the bond cleavage rate. Here, using atomistic molecular dynamics simulations combined with Smoluchowski theory, we propose a model for this behavior. For a broad range of forces and systems, the model reproduces the experimentally observed rates by solving a reaction-diffusion equation for a “protein coordinate” diffusing in a force-dependent effective potential. The atomistic simulations are used to compute, from first principles, the parameters of the model via a quasiharmonic analysis. Additionally, the simulations are also used to provide details about the microscopic degrees of freedom that are important for the underlying mechano-catalysis

  18. A Proposed Stochastic Finite Difference Approach Based on Homogenous Chaos Expansion

    Directory of Open Access Journals (Sweden)

    O. H. Galal

    2013-01-01

    Full Text Available This paper proposes a stochastic finite difference approach, based on homogenous chaos expansion (SFDHC. The said approach can handle time dependent nonlinear as well as linear systems with deterministic or stochastic initial and boundary conditions. In this approach, included stochastic parameters are modeled as second-order stochastic processes and are expanded using Karhunen-Loève expansion, while the response function is approximated using homogenous chaos expansion. Galerkin projection is used in converting the original stochastic partial differential equation (PDE into a set of coupled deterministic partial differential equations and then solved using finite difference method. Two well-known equations were used for efficiency validation of the method proposed. First one being the linear diffusion equation with stochastic parameter and the second is the nonlinear Burger's equation with stochastic parameter and stochastic initial and boundary conditions. In both of these examples, the probability distribution function of the response manifested close conformity to the results obtained from Monte Carlo simulation with optimized computational cost.

  19. Radiative origin of all quark and lepton masses through dark matter with flavor symmetry.

    Science.gov (United States)

    Ma, Ernest

    2014-03-07

    The fundamental issue of the origin of mass for all quarks and leptons (including Majorana neutrinos) is linked to dark matter, odd under an exactly conserved Z2 symmetry which may or may not be derivable from an U(1)D gauge symmetry. The observable sector interacts with a proposed dark sector which consists of heavy neutral singlet Dirac fermions and suitably chosen new scalars. Flavor symmetry is implemented in a renormalizable context with just the one Higgs doublet (ϕ(+), ϕ(0)) of the standard model in such a way that all observed fermions obtain their masses radiatively through dark matter.

  20. Adaptive surrogate model based multiobjective optimization for coastal aquifer management

    Science.gov (United States)

    Song, Jian; Yang, Yun; Wu, Jianfeng; Wu, Jichun; Sun, Xiaomin; Lin, Jin

    2018-06-01

    In this study, a novel surrogate model assisted multiobjective memetic algorithm (SMOMA) is developed for optimal pumping strategies of large-scale coastal groundwater problems. The proposed SMOMA integrates an efficient data-driven surrogate model with an improved non-dominated sorted genetic algorithm-II (NSGAII) that employs a local search operator to accelerate its convergence in optimization. The surrogate model based on Kernel Extreme Learning Machine (KELM) is developed and evaluated as an approximate simulator to generate the patterns of regional groundwater flow and salinity levels in coastal aquifers for reducing huge computational burden. The KELM model is adaptively trained during evolutionary search to satisfy desired fidelity level of surrogate so that it inhibits error accumulation of forecasting and results in correctly converging to true Pareto-optimal front. The proposed methodology is then applied to a large-scale coastal aquifer management in Baldwin County, Alabama. Objectives of minimizing the saltwater mass increase and maximizing the total pumping rate in the coastal aquifers are considered. The optimal solutions achieved by the proposed adaptive surrogate model are compared against those solutions obtained from one-shot surrogate model and original simulation model. The adaptive surrogate model does not only improve the prediction accuracy of Pareto-optimal solutions compared with those by the one-shot surrogate model, but also maintains the equivalent quality of Pareto-optimal solutions compared with those by NSGAII coupled with original simulation model, while retaining the advantage of surrogate models in reducing computational burden up to 94% of time-saving. This study shows that the proposed methodology is a computationally efficient and promising tool for multiobjective optimizations of coastal aquifer managements.

  1. Improved virtual channel noise model for transform domain Wyner-Ziv video coding

    DEFF Research Database (Denmark)

    Huang, Xin; Forchhammer, Søren

    2009-01-01

    Distributed video coding (DVC) has been proposed as a new video coding paradigm to deal with lossy source coding using side information to exploit the statistics at the decoder to reduce computational demands at the encoder. A virtual channel noise model is utilized at the decoder to estimate...... the noise distribution between the side information frame and the original frame. This is one of the most important aspects influencing the coding performance of DVC. Noise models with different granularity have been proposed. In this paper, an improved noise model for transform domain Wyner-Ziv video...... coding is proposed, which utilizes cross-band correlation to estimate the Laplacian parameters more accurately. Experimental results show that the proposed noise model can improve the rate-distortion (RD) performance....

  2. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins

    Science.gov (United States)

    Camina, Eduardo; Güell, Francisco

    2017-01-01

    This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and ordering the latest scientific advances related to this subject. The main forms of memory presented include sensory memory, short-term memory, and long-term memory. Information from the world around us is first stored by sensory memory, thus enabling the storage and future use of such information. Short-term memory (or memory) refers to information processed in a short period of time. Long-term memory allows us to store information for long periods of time, including information that can be retrieved consciously (explicit memory) or unconsciously (implicit memory). PMID:28713278

  3. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins.

    Science.gov (United States)

    Camina, Eduardo; Güell, Francisco

    2017-01-01

    This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and ordering the latest scientific advances related to this subject. The main forms of memory presented include sensory memory, short-term memory, and long-term memory. Information from the world around us is first stored by sensory memory, thus enabling the storage and future use of such information. Short-term memory (or memory) refers to information processed in a short period of time. Long-term memory allows us to store information for long periods of time, including information that can be retrieved consciously (explicit memory) or unconsciously (implicit memory).

  4. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins

    Directory of Open Access Journals (Sweden)

    Eduardo Camina

    2017-06-01

    Full Text Available This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and ordering the latest scientific advances related to this subject. The main forms of memory presented include sensory memory, short-term memory, and long-term memory. Information from the world around us is first stored by sensory memory, thus enabling the storage and future use of such information. Short-term memory (or memory refers to information processed in a short period of time. Long-term memory allows us to store information for long periods of time, including information that can be retrieved consciously (explicit memory or unconsciously (implicit memory.

  5. God particle and origin of mass

    International Nuclear Information System (INIS)

    He Hongjian; Kuang Yuping

    2014-01-01

    The new Higgs boson discovered at the CERN LHC could be the God particle expected from the standard model. This revolutionary discovery opens up a new era of exploring the origin of masses for all elementary particles in the universe. It becomes a turning point of the particle physics in 21 th century. This article presents the following: (1) Scientific importance of searching and testing the God particle(s); (2) The history of studying the origin of mass, and why Newton mechanics and Einstein relativity could not resolve the origin of mass; (3) The mysterious vacuum and the mechanism of spontaneous symmetry breaking; (4) How the God particle was invented and how the LHC might have discovered it; (5) The perspective of seeking the origin of mass and new physics laws. (authors)

  6. Tensile Forces Originating from Cancer Spheroids Facilitate Tumor Invasion.

    Directory of Open Access Journals (Sweden)

    Katarzyna S Kopanska

    Full Text Available The mechanical properties of tumors and the tumor environment provide important information for the progression and characterization of cancer. Tumors are surrounded by an extracellular matrix (ECM dominated by collagen I. The geometrical and mechanical properties of the ECM play an important role for the initial step in the formation of metastasis, presented by the migration of malignant cells towards new settlements as well as the vascular and lymphatic system. The extent of this cell invasion into the ECM is a key medical marker for cancer prognosis. In vivo studies reveal an increased stiffness and different architecture of tumor tissue when compared to its healthy counterparts. The observed parallel collagen organization on the tumor border and radial arrangement at the invasion zone has raised the question about the mechanisms organizing these structures. Here we study the effect of contractile forces originated from model tumor spheroids embedded in a biomimetic collagen I matrix. We show that contractile forces act immediately after seeding and deform the ECM, thus leading to tensile radial forces within the matrix. Relaxation of this tension via cutting the collagen does reduce invasion, showing a mechanical relation between the tensile state of the ECM and invasion. In turn, these results suggest that tensile forces in the ECM facilitate invasion. Furthermore, simultaneous contraction of the ECM and tumor growth leads to the condensation and reorientation of the collagen at the spheroid's surface. We propose a tension-based model to explain the collagen organization and the onset of invasion by forces originating from the tumor.

  7. Proposal of Constraints Analysis Method Based on Network Model for Task Planning

    Science.gov (United States)

    Tomiyama, Tomoe; Sato, Tatsuhiro; Morita, Toyohisa; Sasaki, Toshiro

    Deregulation has been accelerating several activities toward reengineering business processes, such as railway through service and modal shift in logistics. Making those activities successful, business entities have to regulate new business rules or know-how (we call them ‘constraints’). According to the new constraints, they need to manage business resources such as instruments, materials, workers and so on. In this paper, we propose a constraint analysis method to define constraints for task planning of the new business processes. To visualize each constraint's influence on planning, we propose a network model which represents allocation relations between tasks and resources. The network can also represent task ordering relations and resource grouping relations. The proposed method formalizes the way of defining constraints manually as repeatedly checking the network structure and finding conflicts between constraints. Being applied to crew scheduling problems shows that the method can adequately represent and define constraints of some task planning problems with the following fundamental features, (1) specifying work pattern to some resources, (2) restricting the number of resources for some works, (3) requiring multiple resources for some works, (4) prior allocation of some resources to some works and (5) considering the workload balance between resources.

  8. Boundary-layer transition prediction using a simplified correlation-based model

    Directory of Open Access Journals (Sweden)

    Xia Chenchao

    2016-02-01

    Full Text Available This paper describes a simplified transition model based on the recently developed correlation-based γ-Reθt transition model. The transport equation of transition momentum thickness Reynolds number is eliminated for simplicity, and new transition length function and critical Reynolds number correlation are proposed. The new model is implemented into an in-house computational fluid dynamics (CFD code and validated for low and high-speed flow cases, including the zero pressure flat plate, airfoils, hypersonic flat plate and double wedge. Comparisons between the simulation results and experimental data show that the boundary-layer transition phenomena can be reasonably illustrated by the new model, which gives rise to significant improvements over the fully laminar and fully turbulent results. Moreover, the new model has comparable features of accuracy and applicability when compared with the original γ-Reθt model. In the meantime, the newly proposed model takes only one transport equation of intermittency factor and requires fewer correlations, which simplifies the original model greatly. Further studies, especially on separation-induced transition flows, are required for the improvement of the new model.

  9. Compound quarks and gluons and parton confinement (proposal of a different approach)

    International Nuclear Information System (INIS)

    Krolikowski, W.

    1978-01-01

    The author develops further the compound model proposed in 1971, where coloured quarks are factorized into elementary constituents carrying separately the flavour and colour quantum numbers and obeying the 'compensating' wrong statistics. An 'effective quantum chromodynamics' is conjectured, where both coloured quarks and vector gluons (which obey good statistics) are factorized into elementary constituents obeying wrong statistics. Then the Pauli connection of spin and statistics confines these elementary constituents within bound states obeying good statistics. In the parton model approximation with these elementary constituents as partons it prevents also coloured quarks and vector gluons from appearing as free particles. The expected confinement violation for coloured quarks and vector gluons and the observed scaling violation have here a common origin, namely the clustering of elementary constituents inside hadrons. The basic difference between leptons and quarks is related in this model to wrong statistics of elementary constituents involved in the quark structure. (Auth.)

  10. Mathematical model and metaheuristics for simultaneous balancing and sequencing of a robotic mixed-model assembly line

    Science.gov (United States)

    Li, Zixiang; Janardhanan, Mukund Nilakantan; Tang, Qiuhua; Nielsen, Peter

    2018-05-01

    This article presents the first method to simultaneously balance and sequence robotic mixed-model assembly lines (RMALB/S), which involves three sub-problems: task assignment, model sequencing and robot allocation. A new mixed-integer programming model is developed to minimize makespan and, using CPLEX solver, small-size problems are solved for optimality. Two metaheuristics, the restarted simulated annealing algorithm and co-evolutionary algorithm, are developed and improved to address this NP-hard problem. The restarted simulated annealing method replaces the current temperature with a new temperature to restart the search process. The co-evolutionary method uses a restart mechanism to generate a new population by modifying several vectors simultaneously. The proposed algorithms are tested on a set of benchmark problems and compared with five other high-performing metaheuristics. The proposed algorithms outperform their original editions and the benchmarked methods. The proposed algorithms are able to solve the balancing and sequencing problem of a robotic mixed-model assembly line effectively and efficiently.

  11. Modeling High Frequency Data with Long Memory and Structural Change: A-HYEGARCH Model

    Directory of Open Access Journals (Sweden)

    Yanlin Shi

    2018-03-01

    Full Text Available In this paper, we propose an Adaptive Hyperbolic EGARCH (A-HYEGARCH model to estimate the long memory of high frequency time series with potential structural breaks. Based on the original HYGARCH model, we use the logarithm transformation to ensure the positivity of conditional variance. The structural change is further allowed via a flexible time-dependent intercept in the conditional variance equation. To demonstrate its effectiveness, we perform a range of Monte Carlo studies considering various data generating processes with and without structural changes. Empirical testing of the A-HYEGARCH model is also conducted using high frequency returns of S&P 500, FTSE 100, ASX 200 and Nikkei 225. Our simulation and empirical evidence demonstrate that the proposed A-HYEGARCH model outperforms various competing specifications and can effectively control for structural breaks. Therefore, our model may provide more reliable estimates of long memory and could be a widely useful tool for modelling financial volatility in other contexts.

  12. Shaping Cutter Original Profile for Fine-module Ratchet Teeth Cutting

    Science.gov (United States)

    Sharkov, O. V.; Koryagin, S. I.; Velikanov, N. L.

    2018-03-01

    The methods for determining geometric characteristics of a theoretical original profile of the cutter for cutting ratchet teeth with a module of 0.3–1.0 mm are considered in the article. Design models describing the shaping process of cutting edges of cutter teeth are developed. Systems of expressions for determining coordinates of the points of front and back edges of cutter teeth; the workpiece angles of rotation during the cutting process; the minimum cutter radius are received. The basic data when using the proposed technique are: radii of circumferences passing through cavities of cutter teeth and external cut teeth; the gradient angle and length of straight section of the front edge of a cut tooth; angles of rotation of the cutter and the workpiece at the moment of shaping.

  13. Space-Time Uncertainty and Cosmology: a Proposed Quantum Model of the Universe [ 245Kb

    Directory of Open Access Journals (Sweden)

    Tosto S.

    2013-10-01

    Full Text Available The paper introduces a cosmological model of the quantum universe. The aim of the model is (i to identify the possible mechanism that governs the matter/antimatter ratio existing in the universe and concurrently to propose (ii a reasonable growth mechanism of the universe and (iii a possible explanation of the dark energy. The concept of timespace uncertainty, on which is based the present quantum approach, has been proven able to bridge quantum mechanics and relativity.

  14. A combined model based on CEEMDAN and modified flower pollination algorithm for wind speed forecasting

    International Nuclear Information System (INIS)

    Zhang, Wenyu; Qu, Zongxi; Zhang, Kequan; Mao, Wenqian; Ma, Yining; Fan, Xu

    2017-01-01

    Highlights: • A CEEMDAN-CLSFPA combined model is proposed for short-term wind speed forecasting. • The CEEMDAN technique is used to decompose the original wind speed series. • A modified optimization algorithm-CLSFPA is proposed to optimize the weights of the combined model. • The no negative constraint theory is applied to the combined model. • Robustness of the proposed model is validated by data sampled from four different wind farms. - Abstract: Wind energy, which is stochastic and intermittent by nature, has a significant influence on power system operation, power grid security and market economics. Precise and reliable wind speed prediction is vital for wind farm planning and operational planning for power grids. To improve wind speed forecasting accuracy, a large number of forecasting approaches have been proposed; however, these models typically do not account for the importance of data preprocessing and are limited by the use of individual models. In this paper, a novel combined model – combining complete ensemble empirical mode decomposition adaptive noise (CEEMDAN), flower pollination algorithm with chaotic local search (CLSFPA), five neural networks and no negative constraint theory (NNCT) – is proposed for short-term wind speed forecasting. First, a recent CEEMDAN is employed to divide the original wind speed data into a finite set of IMF components, and then a combined model, based on NNCT, is proposed for forecasting each decomposition signal. To improve the forecasting capacity of the combined model, a modified flower pollination algorithm (FPA) with chaotic local search (CLS) is proposed and employed to determine the optimal weight coefficients of the combined model, and the final prediction values were obtained by reconstructing the refined series. To evaluate the forecasting ability of the proposed combined model, 15-min wind speed data from four wind farms in the eastern coastal areas of China are used. The experimental results of

  15. Fast image reconstruction for Compton camera using stochastic origin ensemble approach.

    Science.gov (United States)

    Andreyev, Andriy; Sitek, Arkadiusz; Celler, Anna

    2011-01-01

    Compton camera has been proposed as a potential imaging tool in astronomy, industry, homeland security, and medical diagnostics. Due to the inherent geometrical complexity of Compton camera data, image reconstruction of distributed sources can be ineffective and/or time-consuming when using standard techniques such as filtered backprojection or maximum likelihood-expectation maximization (ML-EM). In this article, the authors demonstrate a fast reconstruction of Compton camera data using a novel stochastic origin ensembles (SOE) approach based on Markov chains. During image reconstruction, the origins of the measured events are randomly assigned to locations on conical surfaces, which are the Compton camera analogs of lines-of-responses in PET. Therefore, the image is defined as an ensemble of origin locations of all possible event origins. During the course of reconstruction, the origins of events are stochastically moved and the acceptance of the new event origin is determined by the predefined acceptance probability, which is proportional to the change in event density. For example, if the event density at the new location is higher than in the previous location, the new position is always accepted. After several iterations, the reconstructed distribution of origins converges to a quasistationary state which can be voxelized and displayed. Comparison with the list-mode ML-EM reveals that the postfiltered SOE algorithm has similar performance in terms of image quality while clearly outperforming ML-EM in relation to reconstruction time. In this study, the authors have implemented and tested a new image reconstruction algorithm for the Compton camera based on the stochastic origin ensembles with Markov chains. The algorithm uses list-mode data, is parallelizable, and can be used for any Compton camera geometry. SOE algorithm clearly outperforms list-mode ML-EM for simple Compton camera geometry in terms of reconstruction time. The difference in computational time

  16. Factors accounting for youth suicide attempt in Hong Kong: a model building.

    Science.gov (United States)

    Wan, Gloria W Y; Leung, Patrick W L

    2010-10-01

    This study aimed at proposing and testing a conceptual model of youth suicide attempt. We proposed a model that began with family factors such as a history of physical abuse and parental divorce/separation. Family relationship, presence of psychopathology, life stressors, and suicide ideation were postulated as mediators, leading to youth suicide attempt. The stepwise entry of the risk factors to a logistic regression model defined their proximity as related to suicide attempt. Path analysis further refined our proposed model of youth suicide attempt. Our originally proposed model was largely confirmed. The main revision was dropping parental divorce/separation as a risk factor in the model due to lack of significant contribution when examined alongside with other risk factors. This model was cross-validated by gender. This study moved research on youth suicide from identification of individual risk factors to model building, integrating separate findings of the past studies.

  17. New variational image decomposition model for simultaneously denoising and segmenting optical coherence tomography images

    International Nuclear Information System (INIS)

    Duan, Jinming; Bai, Li; Tench, Christopher; Gottlob, Irene; Proudlock, Frank

    2015-01-01

    Optical coherence tomography (OCT) imaging plays an important role in clinical diagnosis and monitoring of diseases of the human retina. Automated analysis of optical coherence tomography images is a challenging task as the images are inherently noisy. In this paper, a novel variational image decomposition model is proposed to decompose an OCT image into three components: the first component is the original image but with the noise completely removed; the second contains the set of edges representing the retinal layer boundaries present in the image; and the third is an image of noise, or in image decomposition terms, the texture, or oscillatory patterns of the original image. In addition, a fast Fourier transform based split Bregman algorithm is developed to improve computational efficiency of solving the proposed model. Extensive experiments are conducted on both synthesised and real OCT images to demonstrate that the proposed model outperforms the state-of-the-art speckle noise reduction methods and leads to accurate retinal layer segmentation. (paper)

  18. Eocene and not Cretaceous origin of spider wasps: Fossil evidence from amber

    Directory of Open Access Journals (Sweden)

    Juanita Rodriguez

    2016-02-01

    Full Text Available Spider wasps had long been proposed to originate in the mid-Cretaceous based on the Burmese amber fossil Bryopompilus interfector Engel and Grimaldi, 2006. We performed a morphological examination of this fossil and determined it does not belong to Pompilidae or any other described hymenopteran family. Instead, we place it in the new family Bryopompilidae. The oldest verifiable member of the Pompilidae is from Baltic amber, which suggests the family probably originated in the Eocene, not in the mid-Cretaceous as previously proposed. The origin of spider wasps appears to be correlated with an increase in spider familial diversity in the Cenozoic. We also we add two genera to the extinct pompilid fauna: Tainopompilus gen. nov., and Paleogenia gen. nov., and describe three new species of fossil spider wasps: Anoplius planeta sp. nov., from Dominican amber (Burdigalian to Langhian; Paleogenia wahisi sp. nov., from Baltic amber (Lutetian to Priabonian; and Tainopompilus argentum sp. nov, from Dominican amber (Chattian to Langhian.

  19. Determining passive cooling limits in CPV using an analytical thermal model

    Science.gov (United States)

    Gualdi, Federico; Arenas, Osvaldo; Vossier, Alexis; Dollet, Alain; Aimez, Vincent; Arès, Richard

    2013-09-01

    We propose an original thermal analytical model aiming to predict the practical limits of passive cooling systems for high concentration photovoltaic modules. The analytical model is described and validated by comparison with a commercial 3D finite element model. The limiting performances of flat plate cooling systems in natural convection are then derived and discussed.

  20. Stochastic modeling of friction force and vibration analysis of a mechanical system using the model

    International Nuclear Information System (INIS)

    Kang, Won Seok; Choi, Chan Kyu; Yoo, Hong Hee

    2015-01-01

    The squeal noise generated from a disk brake or chatter occurred in a machine tool primarily results from friction-induced vibration. Since friction-induced vibration is usually accompanied by abrasion and lifespan reduction of mechanical parts, it is necessary to develop a reliable analysis model by which friction-induced vibration phenomena can be accurately analyzed. The original Coulomb's friction model or the modified Coulomb friction model employed in most commercial programs employs deterministic friction coefficients. However, observing friction phenomena between two contact surfaces, one may observe that friction coefficients keep changing due to the unevenness of contact surface, temperature, lubrication and humidity. Therefore, in this study, friction coefficients are modeled as random parameters that keep changing during the motion of a mechanical system undergoing friction force. The integrity of the proposed stochastic friction model was validated by comparing the analysis results obtained by the proposed model with experimental results.

  1. Optimization approach of background value and initial item for improving prediction precision of GM(1,1) model

    Institute of Scientific and Technical Information of China (English)

    Yuhong Wang; Qin Liu; Jianrong Tang; Wenbin Cao; Xiaozhong Li

    2014-01-01

    A combination method of optimization of the back-ground value and optimization of the initial item is proposed. The sequences of the unbiased exponential distribution are simulated and predicted through the optimization of the background value in grey differential equations. The principle of the new information priority in the grey system theory and the rationality of the initial item in the original GM(1,1) model are ful y expressed through the improvement of the initial item in the proposed time response function. A numerical example is employed to il ustrate that the proposed method is able to simulate and predict sequences of raw data with the unbiased exponential distribution and has better simulation performance and prediction precision than the original GM(1,1) model relatively.

  2. Modelling Viscoelasticity of Loudspeaker Suspensions using Retardation Spectra

    DEFF Research Database (Denmark)

    Ritter, Tobias; Agerkvist, Finn T.

    2010-01-01

    , the viscoelastic retardation spectrum, which provides a more fundamental description of the suspension viscoelasticity, is rst used to explain the accuracy of the empirical LOG creep model (Knudsen et al.). Then, two extensions to the LOG model are proposed which include the low and high frequency limit...... of the compliance, not accounted for in the original LOG model. The new creep models are veried by measurements on two 5.5 loudspeakers with different surrounds....

  3. Fuzzy model-based servo and model following control for nonlinear systems.

    Science.gov (United States)

    Ohtake, Hiroshi; Tanaka, Kazuo; Wang, Hua O

    2009-12-01

    This correspondence presents servo and nonlinear model following controls for a class of nonlinear systems using the Takagi-Sugeno fuzzy model-based control approach. First, the construction method of the augmented fuzzy system for continuous-time nonlinear systems is proposed by differentiating the original nonlinear system. Second, the dynamic fuzzy servo controller and the dynamic fuzzy model following controller, which can make outputs of the nonlinear system converge to target points and to outputs of the reference system, respectively, are introduced. Finally, the servo and model following controller design conditions are given in terms of linear matrix inequalities. Design examples illustrate the utility of this approach.

  4. "The Actualized Neurosurgeon": A Proposed Model of Surgical Resident Development.

    Science.gov (United States)

    Lipsman, Nir; Khan, Osaama; Kulkarni, Abhaya V

    2017-03-01

    Modern neurosurgical training is both physically and emotionally demanding, posing significant challenges, new and old, to residents as well as programs attempting to train safe, competent surgeons. Models to describe resident development, such as the Accreditation Council for Graduate Medical Education competencies and milestones, address the acquisition of specific skills but largely ignore the stresses and pressures unique to each stage of resident training. We propose an alternative model of resident development adapted from the developmental psychology literature. Our model identifies the challenges that must be met at each stage of junior, intermediate, and senior and chief residency, leading ultimately to an "actualized" neurosurgeon (i.e., one who has maximized his or her potential). Failure to overcome any 1 of these challenges can lead to specific long-lasting consequences, including regret, identity crisis, incompetence, and bitterness. In contrast, the actualized surgeon is one who has successfully acquired the virtues of hope, will, purpose, fidelity, productivity, leadership, competence, and wisdom. The actualized surgeon not only functions safely, confidently, and professionally, but also successfully navigates the challenges of residency and emerges from them having fulfilled his or her maximal potential. This developmental perspective provides an individualized description of healthy surgical development. Our model allows programs to identify the basis for residents who fail to progress, counsel residents during their training, and perhaps help identify resident candidates who are better prepared to meet the developmental challenges of residency training. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Addendum to a proposal for ATLAS: a precision heavy-ion accelerator at Argonne National Laboratory

    International Nuclear Information System (INIS)

    1978-12-01

    This revised proposal for the construction of the Argonne Tandem-Linac Accelerator System (ATLAS) is in all essentials the same as the proposal originally presented to NUSAC in March 1978. The only differences worth mentioning are the plan to expand the experimental area somewhat more than was originally proposed and an increased cost, brought about principally by inflation. The outline presented is the same as in the original document, reproduced for the convenience of the reader. The objective of the proposed Argonne Tandem-Linac Accelerator System (ATLAS) is to provide precision beams of heavy ions for nuclear physics research in the region of projectile energies comparable to nuclear binding energies (5 to 25 MeV/A). By using the demonstrated potential of superconducting rf technology, beams of exceptional quality and flexibility can be obtained. The proposed system is designed to provide beams with tandem-like energy resolution and ease of energy variation, and the energy range is comparable to that of a approx. 50 MV tandem. In addition, the beam will be bunched into very short (approx. 50 psec) pulses, permitting fast-timing measurements that can open up major new experimental approaches

  6. Origin of switching current transients in TIPS-pentacene based organic thin-film transistor with polymer dielectric

    Science.gov (United States)

    Singh, Subhash; Mohapatra, Y. N.

    2017-06-01

    We have investigated switch-on drain-source current transients in fully solution-processed thin film transistors based on 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) using cross-linked poly-4-vinylphenol as a dielectric. We show that the nature of the transient (increasing or decreasing) depends on both the temperature and the amplitude of the switching pulse at the gate. The isothermal transients are analyzed spectroscopically in a time domain to extract the degree of non-exponentiality and its possible origin in trap kinetics. We propose a phenomenological model in which the exchange of electrons between interfacial ions and traps controls the nature of the drain current transients dictated by the Fermi level position. The origin of interfacial ions is attributed to the essential fabrication step of UV-ozone treatment of the dielectric prior to semiconductor deposition.

  7. An Original Stepwise Multilevel Logistic Regression Analysis of Discriminatory Accuracy

    DEFF Research Database (Denmark)

    Merlo, Juan; Wagner, Philippe; Ghith, Nermin

    2016-01-01

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

  8. Statistical Compression for Climate Model Output

    Science.gov (United States)

    Hammerling, D.; Guinness, J.; Soh, Y. J.

    2017-12-01

    Numerical climate model simulations run at high spatial and temporal resolutions generate massive quantities of data. As our computing capabilities continue to increase, storing all of the data is not sustainable, and thus is it important to develop methods for representing the full datasets by smaller compressed versions. We propose a statistical compression and decompression algorithm based on storing a set of summary statistics as well as a statistical model describing the conditional distribution of the full dataset given the summary statistics. We decompress the data by computing conditional expectations and conditional simulations from the model given the summary statistics. Conditional expectations represent our best estimate of the original data but are subject to oversmoothing in space and time. Conditional simulations introduce realistic small-scale noise so that the decompressed fields are neither too smooth nor too rough compared with the original data. Considerable attention is paid to accurately modeling the original dataset-one year of daily mean temperature data-particularly with regard to the inherent spatial nonstationarity in global fields, and to determining the statistics to be stored, so that the variation in the original data can be closely captured, while allowing for fast decompression and conditional emulation on modest computers.

  9. A hybrid reliability algorithm using PSO-optimized Kriging model and adaptive importance sampling

    Science.gov (United States)

    Tong, Cao; Gong, Haili

    2018-03-01

    This paper aims to reduce the computational cost of reliability analysis. A new hybrid algorithm is proposed based on PSO-optimized Kriging model and adaptive importance sampling method. Firstly, the particle swarm optimization algorithm (PSO) is used to optimize the parameters of Kriging model. A typical function is fitted to validate improvement by comparing results of PSO-optimized Kriging model with those of the original Kriging model. Secondly, a hybrid algorithm for reliability analysis combined optimized Kriging model and adaptive importance sampling is proposed. Two cases from literatures are given to validate the efficiency and correctness. The proposed method is proved to be more efficient due to its application of small number of sample points according to comparison results.

  10. Proposal of custom made wrist orthoses based on 3D modelling and 3D printing.

    Science.gov (United States)

    Abreu de Souza, Mauren; Schmitz, Cristiane; Marega Pinhel, Marcelo; Palma Setti, Joao A; Nohama, Percy

    2017-07-01

    Accessibility to three-dimensional (3D) technologies, such as 3D scanning systems and additive manufacturing (like 3D printers), allows a variety of 3D applications. For medical applications in particular, these modalities are gaining a lot of attention enabling several opportunities for healthcare applications. The literature brings several cases applying both technologies, but none of them focus on the spreading of how this technology could benefit the health segment. This paper proposes a new methodology, which employs both 3D modelling and 3D printing for building orthoses, which could better fit the demands of different patients. Additionally, there is an opportunity for sharing expertise, as it represents a trendy in terms of the maker-movement. Therefore, as a result of the proposed approach, we present a case study based on a volunteer who needs an immobilization orthosis, which was built for exemplification of the whole process. This proposal also employs freely available 3D models and software, having a strong social impact. As a result, it enables the implementation and effective usability for a variety of built to fit solutions, hitching useful and smarter technologies for the healthcare sector.

  11. Validation of a Perceptual Distraction Model in a Complex Personal Sound Zone System

    DEFF Research Database (Denmark)

    Rämö, Jussi; Marsh, Steven; Bech, Søren

    2016-01-01

    This paper evaluates a previously proposed perceptual model predicting user’s perceived distraction caused by interfering audio programmes. The distraction model was originally trained using a simple sound reproduction system for music-on-music interference situations and it has not been formally...

  12. A model for the origin of bursty star formation in galaxies

    Science.gov (United States)

    Faucher-Giguère, Claude-André

    2018-01-01

    We propose a simple analytic model to understand when star formation is time steady versus bursty in galaxies. Recent models explain the observed Kennicutt-Schmidt relation between star formation rate and gas surface densities in galaxies as resulting from a balance between stellar feedback and gravity. We argue that bursty star formation occurs when such an equilibrium cannot be stably sustained, and identify two regimes in which galaxy-scale star formation should be bursty: (i) at high redshift (z ≳ 1) for galaxies of all masses, and (ii) at low masses (depending on gas fraction) for galaxies at any redshift. At high redshift, characteristic galactic dynamical time-scales become too short for supernova feedback to effectively respond to gravitational collapse in galactic discs (an effect recently identified for galactic nuclei), whereas in dwarf galaxies star formation occurs in too few bright star-forming regions to effectively average out. Burstiness is also enhanced at high redshift owing to elevated gas fractions in the early Universe. Our model can thus explain the bursty star formation rates predicted in these regimes by recent high-resolution galaxy formation simulations, as well as the bursty star formation histories observationally inferred in both local dwarf and high-redshift galaxies. In our model, bursty star formation is associated with particularly strong spatiotemporal clustering of supernovae. Such clustering can promote the formation of galactic winds and our model may thus also explain the much higher wind mass loading factors inferred in high-redshift massive galaxies relative to their z ∼ 0 counterparts.

  13. Origin, behaviour and fate of radionuclides in continental waters

    International Nuclear Information System (INIS)

    Eyrolle-Boyer, Frederique

    2015-01-01

    In this report for Accreditation to Supervise Research (HDR), the author first proposes an overview of his research works to outline how they relate to each other, and gives a summary of his PhD and post-PhD research works. Then, he more particularly reports and comments his works related to the origin of radionuclides: natural and artificial origin, liquid releases from nuclear installations, persistence of atmospheric fall-outs due to surface nuclear tests and to the Chernobyl accident, atmospheric fall-outs in France due to the Fukushima accident. He comments results obtained by another researcher related to the tracing of radionuclide origin in the Rhone river, and reports activity level measurements performed within French waters (and more particularly in the Rhone river, and in irrigation canals). He proposes a focus of the behaviour and coefficients of solid/solution distribution in the case of the Rhone river and of Fukushima water streams. He briefly comments the radiological quality of drinking waters (exposure to radiations and regulation, case of the Rhone river and of neighbouring coastal rivers). He discusses the flow of radionuclides towards the sea environment and proposes some material assessments. Results of various researches performed by the author or made under his supervision are discussed. They relate to extreme events (impact of floods on contaminant transport), to storages and sedimentary archives, and to the use of tritium and carbon 14 to study long cycles. Research perspectives are then discussed on various issues: consequences of typhoons and roles of organic particles in the transport or transfer of radioactivity in the case of Fukushima rivers, estuarine reactions [fr

  14. Development of the nervus terminalis: origin and migration.

    Science.gov (United States)

    Whitlock, Kathleen E

    2004-09-01

    The origin of the nervus terminalis is one of the least well understood developmental events involved in generating the cranial ganglia of the forebrain in vertebrate animals. This cranial nerve forms at the formidable interface of the anteriormost limits of migrating cranial neural crest cells, the terminal end of the neural tube and the differentiating olfactory and adenohypophyseal placodes. The complex cellular interactions that give rise to the various structures associated with the sensory placode (olfactory) and endocrine placode (adenohypophysis) surround and engulf this enigmatic cranial nerve. The tortured history of nervus terminalis development (see von Bartheld, this issue, pages 13-24) reflects the lack of consensus on the origin (or origins), as well as the experimental difficulties in uncovering the origin, of the nervus terminalis. Recent technical advances have allowed us to make headway in understanding the origin(s) of this nerve. The emergence of the externally fertilized zebrafish embryo as a model system for developmental biology and genetics has shed new light on this century-old problem. Coupled with new developmental models are techniques that allow us to trace lineage, visualize gene expression, and genetically ablate cells, adding to our experimental tools with which to follow up on studies provided by our scientific predecessors. Through these techniques, a picture is emerging in which the origin of at least a subset of the nervus terminalis cells lies in the cranial neural crest. In this review, the data surrounding this finding will be discussed in light of recent findings on neural crest and placode origins. Copyright 2004 Wiley-Liss, Inc.

  15. Kernel Method Based Human Model for Enhancing Interactive Evolutionary Optimization

    Science.gov (United States)

    Zhao, Qiangfu; Liu, Yong

    2015-01-01

    A fitness landscape presents the relationship between individual and its reproductive success in evolutionary computation (EC). However, discrete and approximate landscape in an original search space may not support enough and accurate information for EC search, especially in interactive EC (IEC). The fitness landscape of human subjective evaluation in IEC is very difficult and impossible to model, even with a hypothesis of what its definition might be. In this paper, we propose a method to establish a human model in projected high dimensional search space by kernel classification for enhancing IEC search. Because bivalent logic is a simplest perceptual paradigm, the human model is established by considering this paradigm principle. In feature space, we design a linear classifier as a human model to obtain user preference knowledge, which cannot be supported linearly in original discrete search space. The human model is established by this method for predicting potential perceptual knowledge of human. With the human model, we design an evolution control method to enhance IEC search. From experimental evaluation results with a pseudo-IEC user, our proposed model and method can enhance IEC search significantly. PMID:25879050

  16. Identification of Differentially Expressed Genes between Original Breast Cancer and Xenograft Using Machine Learning Algorithms

    Directory of Open Access Journals (Sweden)

    Deling Wang

    2018-03-01

    Full Text Available Breast cancer is one of the most common malignancies in women. Patient-derived tumor xenograft (PDX model is a cutting-edge approach for drug research on breast cancer. However, PDX still exhibits differences from original human tumors, thereby challenging the molecular understanding of tumorigenesis. In particular, gene expression changes after tissues are transplanted from human to mouse model. In this study, we propose a novel computational method by incorporating several machine learning algorithms, including Monte Carlo feature selection (MCFS, random forest (RF, and rough set-based rule learning, to identify genes with significant expression differences between PDX and original human tumors. First, 831 breast tumors, including 657 PDX and 174 human tumors, were collected. Based on MCFS and RF, 32 genes were then identified to be informative for the prediction of PDX and human tumors and can be used to construct a prediction model. The prediction model exhibits a Matthews coefficient correlation value of 0.777. Seven interpretable interactions within the informative gene were detected based on the rough set-based rule learning. Furthermore, the seven interpretable interactions can be well supported by previous experimental studies. Our study not only presents a method for identifying informative genes with differential expression but also provides insights into the mechanism through which gene expression changes after being transplanted from human tumor into mouse model. This work would be helpful for research and drug development for breast cancer.

  17. Identification of Differentially Expressed Genes between Original Breast Cancer and Xenograft Using Machine Learning Algorithms.

    Science.gov (United States)

    Wang, Deling; Li, Jia-Rui; Zhang, Yu-Hang; Chen, Lei; Huang, Tao; Cai, Yu-Dong

    2018-03-12

    Breast cancer is one of the most common malignancies in women. Patient-derived tumor xenograft (PDX) model is a cutting-edge approach for drug research on breast cancer. However, PDX still exhibits differences from original human tumors, thereby challenging the molecular understanding of tumorigenesis. In particular, gene expression changes after tissues are transplanted from human to mouse model. In this study, we propose a novel computational method by incorporating several machine learning algorithms, including Monte Carlo feature selection (MCFS), random forest (RF), and rough set-based rule learning, to identify genes with significant expression differences between PDX and original human tumors. First, 831 breast tumors, including 657 PDX and 174 human tumors, were collected. Based on MCFS and RF, 32 genes were then identified to be informative for the prediction of PDX and human tumors and can be used to construct a prediction model. The prediction model exhibits a Matthews coefficient correlation value of 0.777. Seven interpretable interactions within the informative gene were detected based on the rough set-based rule learning. Furthermore, the seven interpretable interactions can be well supported by previous experimental studies. Our study not only presents a method for identifying informative genes with differential expression but also provides insights into the mechanism through which gene expression changes after being transplanted from human tumor into mouse model. This work would be helpful for research and drug development for breast cancer.

  18. Efficient Output Solution for Nonlinear Stochastic Optimal Control Problem with Model-Reality Differences

    Directory of Open Access Journals (Sweden)

    Sie Long Kek

    2015-01-01

    Full Text Available A computational approach is proposed for solving the discrete time nonlinear stochastic optimal control problem. Our aim is to obtain the optimal output solution of the original optimal control problem through solving the simplified model-based optimal control problem iteratively. In our approach, the adjusted parameters are introduced into the model used such that the differences between the real system and the model used can be computed. Particularly, system optimization and parameter estimation are integrated interactively. On the other hand, the output is measured from the real plant and is fed back into the parameter estimation problem to establish a matching scheme. During the calculation procedure, the iterative solution is updated in order to approximate the true optimal solution of the original optimal control problem despite model-reality differences. For illustration, a wastewater treatment problem is studied and the results show the efficiency of the approach proposed.

  19. The embryonic origin of the ampullate silk glands of the spider Cupiennius salei.

    Science.gov (United States)

    Hilbrant, Maarten; Damen, Wim G M

    2015-05-01

    Silk production in spiders is considered a key innovation, and to have been vital for the diversification of the clade. The evolutionary origin of the organs involved in spider silk production, however, and in particular of the silk glands, is poorly understood. Homologies have been proposed between these and other glands found in arachnids, but lacking knowledge of the embryonic development of spider silk glands hampers an evaluation of hypotheses. This study focuses on the embryonic origin of the largest silk glands of the spider Cupiennius salei, the major and minor ampullate glands. We show how the ampullate glands originate from ectodermal invaginations on the embryonic spinneret limb buds, in relation to morphogenesis of these buds. Moreover, we visualize the subsequent growth of the ampullate glands in sections of the early postembryonic stages. The invaginations are shown to correlate with expression of the proneural gene CsASH2, which is remarkable since it has been proposed that spider silk glands and their nozzles originate from sensory bristles. Hence, by confirming the ectodermal origin of spider silk glands, and by describing the (post-)embryonic morphogenesis of the ampullate glands, this work provides a starting point for further investigating into the genetic program that underlies their development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Determining the origin of synchronous multifocal bladder cancer by exome sequencing

    International Nuclear Information System (INIS)

    Acar, Ömer; Özkurt, Ezgi; Demir, Gulfem; Saraç, Hilal; Alkan, Can; Esen, Tarık; Somel, Mehmet; Lack, Nathan A.

    2015-01-01

    Synchronous multifocal tumours are commonly observed in urothelial carcinomas of the bladder. The origin of these physically independent tumours has been proposed to occur by either intraluminal migration (clonal) or spontaneous transformation of multiple cells by carcinogens (field effect). It is unclear which model is correct, with several studies supporting both hypotheses. A potential cause of this uncertainty may be the small number of genetic mutations previously used to quantify the relationship between these tumours. To better understand the genetic lineage of these tumours we conducted exome sequencing of synchronous multifocal pTa urothelial bladder cancers at a high depth, using multiple samples from three patients. Phylogenetic analysis of high confidence single nucleotide variants (SNV) demonstrated that the sequenced multifocal bladder cancers arose from a clonal origin in all three patients (bootstrap value 100 %). Interestingly, in two patients the most common type of tumour-associated SNVs were cytosine mutations of TpC* dinucleotides (Fisher’s exact test p < 10 −41 ), likely caused by APOBEC-mediated deamination. Incorporating these results into our clonal model, we found that TpC* type mutations occurred 2-5× more often among SNVs on the ancestral branches than in the more recent private branches (p < 10 −4 ) suggesting that TpC* mutations largely occurred early in the development of the tumour. These results demonstrate that synchronous multifocal bladder cancers frequently arise from a clonal origin. Our data also suggests that APOBEC-mediated mutations occur early in the development of the tumour and may be a driver of tumourigenesis in non-muscle invasive urothelial bladder cancer. The online version of this article (doi:10.1186/s12885-015-1859-8) contains supplementary material, which is available to authorized users

  1. Modelling the Errors of EIA’s Oil Prices and Production Forecasts by the Grey Markov Model

    Directory of Open Access Journals (Sweden)

    Gholam Hossein Hasantash

    2012-01-01

    Full Text Available Grey theory is about systematic analysis of limited information. The Grey-Markov model can improve the accuracy of forecast range in the random fluctuating data sequence. In this paper, we employed this model in energy system. The average errors of Energy Information Administrations predictions for world oil price and domestic crude oil production from 1982 to 2007 and from 1985 to 2008 respectively were used as two forecasted examples. We showed that the proposed Grey-Markov model can improve the forecast accuracy of original Grey forecast model.

  2. A self-report measure for the ICD-11 dimensional trait model proposal: The personality inventory for ICD-11.

    Science.gov (United States)

    Oltmanns, Joshua R; Widiger, Thomas A

    2018-02-01

    Proposed for the 11th edition of the World Health Organization's International Classification of Diseases (ICD-11) is a dimensional trait model for the classification of personality disorder (Tyrer, Reed, & Crawford, 2015). The ICD-11 proposal consists of 5 broad domains: negative affective, detachment, dissocial, disinhibition, and anankastic (Mulder, Horwood, Tyrer, Carter, & Joyce, 2016). Several field trials have examined this proposal, yet none has included a direct measure of the trait model. The purpose of the current study was to develop and provide initial validation for the Personality Inventory for ICD-11 (PiCD), a self-report measure of this proposed 5-domain maladaptive trait model. Item selection and scale construction proceeded through 3 initial data collections assessing potential item performance. Two subsequent studies were conducted for scale validation. In Study 1, the PiCD was evaluated in a sample of 259 MTurk participants (who were or had been receiving mental health treatment) with respect to 2 measures of general personality structure: The Eysenck Personality Questionnaire-Revised and the 5-Dimensional Personality Test. In Study 2, the PiCD was evaluated in an additional sample of 285 participants with respect to 2 measures of maladaptive personality traits: The Personality Inventory for DSM-5 and the Computerized Adaptive Test for Personality Disorders. Study 3 provides an item-level exploratory structural equation model with the combined samples from Studies 1 and 2. The results are discussed with respect to the validity of the measure and the potential benefits for future research in having a direct, self-report measure of the ICD-11 trait proposal. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  3. APC-PC Combined Scheme in Gilbert Two State Model: Proposal and Study

    Science.gov (United States)

    Bulo, Yaka; Saring, Yang; Bhunia, Chandan Tilak

    2017-04-01

    In an automatic repeat request (ARQ) scheme, a packet is retransmitted if it gets corrupted due to transmission errors caused by the channel. However, an erroneous packet may contain both erroneous bits and correct bits and hence it may still contain useful information. The receiver may be able to combine this information from multiple erroneous copies to recover the correct packet. Packet combining (PC) is a simple and elegant scheme of error correction in transmitted packet, in which two received copies are XORed to obtain the bit location of erroneous bits. Thereafter, the packet is corrected by bit inversion of bit located as erroneous. Aggressive packet combining (APC) is a logic extension of PC primarily designed for wireless communication with objective of correcting error with low latency. PC offers higher throughput than APC, but PC does not correct double bit errors if occur in same bit location of erroneous copies of the packet. A hybrid technique is proposed to utilize the advantages of both APC and PC while attempting to remove the limitation of both. In the proposed technique, applications of APC-PC on Gilbert two state model has been studied. The simulation results show that the proposed technique offers better throughput than the conventional APC and lesser packet error rate than PC scheme.

  4. Alternative Specifications for the Lévy Libor Market Model: An Empirical Investigation

    DEFF Research Database (Denmark)

    Skovmand, David; Nicolato, Elisa

    This paper introduces and analyzes specications of the Lévy Market Model originally proposed by Eberlein and Özkan (2005). An investigation of the term structure of option implied moments rules out the Brownian motion and homogeneous Lévy processes as suitable modeling devices, and consequently a...

  5. Lizimetric investigation of vertical transportation of Cs-137 in the different soil types for the different raining conditions: a new solution proposal and application for the Chernobyl accident

    International Nuclear Information System (INIS)

    Varinlioglu, A.

    2000-12-01

    driven from experiments which were reached by classical model calculations harmonies well with the present results. Although the present results and the conclusion reached by classical model calculations harmonies, it is observed that there are important differences between them. The vertical transportation in soil was slower in the present experiments than the classical model calculations. As a reason of this difference, it can be showed that the darcy speed which is an ideal speed for soil that is used in the classical model calculation, doesn't agree with the realistic speed that can be changing according to soil type and characteristics. In order to avoid the important differences between the classical model calculation and present experimental results, a new solution for the semi infinite convection diffusional model is proposed in the originality of this Ph.D. thesis. In this proposal of water which is taken by the darcy speed is decreased by a value of the ratio of the migration coefficient to the darcy speed. The result obtained by our new solution proposal agrees quite well with our experimental result. The results that are reached by new solution proposal for different soil types and every raining regimes are harmonies with the sequence of our experiment. Meanwhile the conclusion that is reached for the different raining regime and every soil type also harmonies with the experimental results. As a result the conclusion that is reached in new solution proposal is suitable as ones in the classical model calculations to the experiment. If we compare the results with the experimental ones, we see that our new solution agrees better than the classical model results. Therefore new solution proposal that is the originality of this Ph.D. thesis more realistic than the classical model. Moreover this proposed solution is used to examine a realistic applicational case, that is the of the nuclear reactor accident in Chernobyl in 26 April 1986 which was occurred in Ukraine

  6. Comparison of microfacet BRDF model to modified Beckmann-Kirchhoff BRDF model for rough and smooth surfaces.

    Science.gov (United States)

    Butler, Samuel D; Nauyoks, Stephen E; Marciniak, Michael A

    2015-11-02

    A popular class of BRDF models is the microfacet models, where geometric optics is assumed. In contrast, more complex physical optics models may more accurately predict the BRDF, but the calculation is more resource intensive. These seemingly disparate approaches are compared in detail for the rough and smooth surface approximations of the modified Beckmann-Kirchhoff BRDF model, assuming Gaussian surface statistics. An approximation relating standard Fresnel reflection with the semi-rough surface polarization term, Q, is presented for unpolarized light. For rough surfaces, the angular dependence of direction cosine space is shown to be identical to the angular dependence in the microfacet distribution function. For polished surfaces, the same comparison shows a breakdown in the microfacet models. Similarities and differences between microfacet BRDF models and the modified Beckmann-Kirchhoff model are identified. The rationale for the original Beckmann-Kirchhoff F(bk)(2) geometric term relative to both microfacet models and generalized Harvey-Shack model is presented. A modification to the geometric F(bk)(2) term in original Beckmann-Kirchhoff BRDF theory is proposed.

  7. A proposed model of psychodynamic psychotherapy linked to Erik Erikson's eight stages of psychosocial development.

    Science.gov (United States)

    Knight, Zelda Gillian

    2017-09-01

    Just as Freud used stages of psychosexual development to ground his model of psychoanalysis, it is possible to do the same with Erik Erikson's stages of development with regards to a model of psychodynamic psychotherapy. This paper proposes an eight-stage model of psychodynamic psychotherapy linked to Erik Erikson's eight stages of psychosocial development. Various suggestions are offered. One such suggestion is that as each of Erikson's developmental stages is triggered by a crisis, in therapy it is triggered by the client's search. The resolution of the search often leads to the development of another search, which implies that the therapy process comprises a series of searches. This idea of a series of searches and resolutions leads to the understanding that identity is developmental and therapy is a space in which a new sense of identity may emerge. The notion of hope is linked to Erikson's stage of Basic Trust and the proposed model of therapy views hope and trust as essential for the therapy process. Two clinical vignettes are offered to illustrate these ideas. Psychotherapy can be approached as an eight-stage process and linked to Erikson's eight stages model of development. Psychotherapy may be viewed as a series of searches and thus as a developmental stage resolution process, which leads to the understanding that identity is ongoing throughout the life span. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Determining metal origins and availability in fluvial deposits by analysis of geochemical baselines and solid-solution partitioning measurements and modelling.

    Science.gov (United States)

    Vijver, Martina G; Spijker, Job; Vink, Jos P M; Posthuma, Leo

    2008-12-01

    Metals in floodplain soils and sediments (deposits) can originate from lithogenic and anthropogenic sources, and their availability for uptake in biota is hypothesized to depend on both origin and local sediment conditions. In criteria-based environmental risk assessments, these issues are often neglected, implying local risks to be often over-estimated. Current problem definitions in river basin management tend to require a refined, site-specific focus, resulting in a need to address both aspects. This paper focuses on the determination of local environmental availabilities of metals in fluvial deposits by addressing both the origins of the metals and their partitioning over the solid and solution phases. The environmental availability of metals is assumed to be a key force influencing exposure levels in field soils and sediments. Anthropogenic enrichments of Cu, Zn and Pb in top layers could be distinguished from lithogenic background concentrations and described using an aluminium-proxy. Cd in top layers was attributed to anthropogenic enrichment almost fully. Anthropogenic enrichments for Cu and Zn appeared further to be also represented by cold 2M HNO3 extraction of site samples. For Pb the extractions over-estimated the enrichments. Metal partitioning was measured, and measurements were compared to predictions generated by an empirical regression model and by a mechanistic-kinetic model. The partitioning models predicted metal partitioning in floodplain deposits within about one order of magnitude, though a large inter-sample variability was found for Pb.

  9. A Nineteenth-Century French Proposal to Use School Vouchers.

    Science.gov (United States)

    Van Vliet, W.; Smyth, J. A.

    1982-01-01

    In light of the current American interest in school vouchers as proposed by economist Milton Friedman, recapitulates the origins, content, and fate of an 1872 law drafted by a French parliamentary commission to establish a countrywide voucher scheme for primary schools. (NEC)

  10. Proposed man-rem reference values of occupational exposure

    International Nuclear Information System (INIS)

    Lombard, J.

    1988-04-01

    This report presents a proposal of referent collective dose (man-rem) values for occupational exposure related to operation of French pressurized water reactors. These values, permitting adequate choice of protection both at design and operation level, are dependent on the level of annual individual doses. The man-rem value, originating from annual individual doses less than 0.5 rem are estimated to 1 kf. The proposed value is 20 kf for annual individual exposures between 0.5 and 3 rem, and 90 kf for annual individual exposures between 3 and 5 rem. (author) [fr

  11. An EMD–SARIMA-Based Modeling Approach for Air Traffic Forecasting

    Directory of Open Access Journals (Sweden)

    Wei Nai

    2017-12-01

    Full Text Available The ever-increasing air traffic demand in China has brought huge pressure on the planning and management of, and investment in, air terminals as well as airline companies. In this context, accurate and adequate short-term air traffic forecasting is essential for the operations of those entities. In consideration of such a problem, a hybrid air traffic forecasting model based on empirical mode decomposition (EMD and seasonal auto regressive integrated moving average (SARIMA has been proposed in this paper. The model proposed decomposes the original time series into components at first, and models each component with the SARIMA forecasting model, then integrates all the models together to form the final combined forecast result. By using the monthly air cargo and passenger flow data from the years 2006 to 2014 available at the official website of the Civil Aviation Administration of China (CAAC, the effectiveness in forecasting of the model proposed has been demonstrated, and by a horizontal performance comparison between several other widely used forecasting models, the advantage of the proposed model has also been proved.

  12. Proposal of the mathematical model of the aquifer for interpretation of measurements of natural isotopes in the water

    International Nuclear Information System (INIS)

    Nawalany, M.

    1975-01-01

    Mathematical models applied in isotope hydrology are presented in the paper. The most commonly used deterministic models are discussed in the first part of the paper including the piston flow and good mixing models. The model of nonideal mixing is introduced by the author into the hydrological considerations. This model is a generalization of the good mixing model and allows for different processes of mixing of natural isotopes in waters of hydrological systems. The most important stochastic model i.e. the dispersive model is discussed too. The ''three-velocities'' model is proposed the first time by the author. The ''three-velocities'' model differs from the other ones in following properties: it includes finite flow velocity of the tracer particles, it takes into account the presence of stagnant water, it satisfied the law of fluid continuity, it is convergent to the piston-flow model in limit. However the model proposed describes dispersion phenomenon and satisfied the tracer conservation law (i.e. standarization) - the two properties characteristic of all the models. The author's strong belief is that the user (hydrologist) having at his disposal given below review of the models will be able to choose the most adequate model in given hydrological conditions. (author)

  13. Child-Labor Proposal Eyes Private Model

    Science.gov (United States)

    Cech, Scott J.

    2007-01-01

    Proposed child-labor-rule changes--the most ambitious in 30 years--would carve out a permanent exemption to U.S. Department of Labor regulations for the work-study program run by a national network of Roman Catholic high schools. The program is a requirement of the Chicago-based Cristo Rey Network, which now has 12 high schools around the country…

  14. Towards an E-market Model

    DEFF Research Database (Denmark)

    Ivang, Reimer; Hinson, Robert; Somasundaram, Ramanathan

    2006-01-01

    on the literature survey and ídentification of gaps in the present e-market definitive models, the authors postulate a preliminary e-market reference model. Originality/ Value: Through synthesizing the e-market literature, and by taking into account contemporary e-market developments, key dimensions that define......Purpose: Seeks to argue that there are problems associated with e-market definitive efforts and consequently seeks proposes a new e-market model. Design/methodology/Approach: Paper based largely on literature survey and an assessment of the existing e-market conceptualizations. Findings: Based...

  15. Identifying Galactic Cosmic Ray Origins With Super-TIGER

    Science.gov (United States)

    deNolfo, Georgia; Binns, W. R.; Israel, M. H.; Christian, E. R.; Mitchell, J. W.; Hams, T.; Link, J. T.; Sasaki, M.; Labrador, A. W.; Mewaldt, R. A.; hide

    2009-01-01

    Super-TIGER (Super Trans-Iron Galactic Element Recorder) is a new long-duration balloon-borne instrument designed to test and clarify an emerging model of cosmic-ray origins and models for atomic processes by which nuclei are selected for acceleration. A sensitive test of the origin of cosmic rays is the measurement of ultra heavy elemental abundances (Z > or equal 30). Super-TIGER is a large-area (5 sq m) instrument designed to measure the elements in the interval 30 TIGER builds on the heritage of the smaller TIGER, which produced the first well-resolved measurements of elemental abundances of the elements Ga-31, Ge-32, and Se-34. We present the Super-TIGER design, schedule, and progress to date, and discuss the relevance of UH measurements to cosmic-ray origins.

  16. Longitudinal and Integrative Tests of Family Stress Model Effects on Mexican-Origin Adolescents

    Science.gov (United States)

    White, Rebecca M. B.; Liu, Yu; Nair, Rajni L.; Tein, Jenn-Yun

    2015-01-01

    The family stress model represents a common framework through which to examine the effects of environmental stressors on adolescent adjustment. The model suggests that economic and neighborhood stressors influence youth adjustment via disruptions to parenting. Incorporating integrative developmental theory, we examined the degree to which parents’ cultural value orientations mitigated the effects of stressors on parenting disruptions and the degree to which environmental adversity qualified the effect of parenting on adolescent adjustment. We tested the hypothesized Integrative Family Stress Model longitudinally in a sample of mother-youth dyads (N = 749) and father-youth dyads (N = 467) from Mexican origin families, across three times points spanning early to middle adolescence. Providing the first longitudinal evidence of family stress mediated effects, mothers’ perceptions of economic pressure were associated with increases in adolescent externalizing symptoms five years later via intermediate increases in harsh parenting. The remaining findings supported the notion that integrative developmental theory can inform family stress model hypothesis testing that is culturally and contextually relevant for wide range of diverse families and youth. For example, fathers’ perceptions of economic pressure and neighborhood danger had important implications for adolescent internalizing, via reductions in paternal warmth, but only at certain levels of neighborhood adversity. Mothers’ familism value orientations mitigated the effects of economic pressure on maternal warmth, protecting their adolescents from experiencing developmental costs associated with environmental stressors. Results are discussed in terms of identifying how integrative developmental theory intersects with the family stress model to set diverse youth on different developmental pathways. PMID:25751100

  17. A new neural network model for solving random interval linear programming problems.

    Science.gov (United States)

    Arjmandzadeh, Ziba; Safi, Mohammadreza; Nazemi, Alireza

    2017-05-01

    This paper presents a neural network model for solving random interval linear programming problems. The original problem involving random interval variable coefficients is first transformed into an equivalent convex second order cone programming problem. A neural network model is then constructed for solving the obtained convex second order cone problem. Employing Lyapunov function approach, it is also shown that the proposed neural network model is stable in the sense of Lyapunov and it is globally convergent to an exact satisfactory solution of the original problem. Several illustrative examples are solved in support of this technique. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Effective Solar Indices for Ionospheric Modeling: A Review and a Proposal for a Real-Time Regional IRI

    Science.gov (United States)

    Pignalberi, A.; Pezzopane, M.; Rizzi, R.; Galkin, I.

    2018-01-01

    The first part of this paper reviews methods using effective solar indices to update a background ionospheric model focusing on those employing the Kriging method to perform the spatial interpolation. Then, it proposes a method to update the International Reference Ionosphere (IRI) model through the assimilation of data collected by a European ionosonde network. The method, called International Reference Ionosphere UPdate (IRI UP), that can potentially operate in real time, is mathematically described and validated for the period 9-25 March 2015 (a time window including the well-known St. Patrick storm occurred on 17 March), using IRI and IRI Real Time Assimilative Model (IRTAM) models as the reference. It relies on foF2 and M(3000)F2 ionospheric characteristics, recorded routinely by a network of 12 European ionosonde stations, which are used to calculate for each station effective values of IRI indices IG_{12} and R_{12} (identified as IG_{{12{eff}}} and R_{{12{eff}}}); then, starting from this discrete dataset of values, two-dimensional (2D) maps of IG_{{12{eff}}} and R_{{12{eff}}} are generated through the universal Kriging method. Five variogram models are proposed and tested statistically to select the best performer for each effective index. Then, computed maps of IG_{{12{eff}}} and R_{{12{eff}}} are used in the IRI model to synthesize updated values of foF2 and hmF2. To evaluate the ability of the proposed method to reproduce rapid local changes that are common under disturbed conditions, quality metrics are calculated for two test stations whose measurements were not assimilated in IRI UP, Fairford (51.7°N, 1.5°W) and San Vito (40.6°N, 17.8°E), for IRI, IRI UP, and IRTAM models. The proposed method turns out to be very effective under highly disturbed conditions, with significant improvements of the foF2 representation and noticeable improvements of the hmF2 one. Important improvements have been verified also for quiet and moderately disturbed

  19. Numerical modeling of dynamics of heart rate and arterial pressure during passive orthostatic test

    Science.gov (United States)

    Ishbulatov, Yu. M.; Kiselev, A. R.; Karavaev, A. S.

    2018-04-01

    A model of human cardiovascular system is proposed to describe the main heart rhythm, influence of autonomous regulation on frequency and strength of heart contractions and resistance of arterial vessels; process of formation of arterial pressure during systolic and diastolic phases; influence of respiration; synchronization between loops of autonomous regulation. The proposed model is used to simulate the dynamics of heart rate and arterial pressure during passive transition from supine to upright position. Results of mathematical modeling are compared to original experimental data.

  20. The origin of the western constellations (II). (Italian Title: Líorigine delle costellazioni occidentali (II parte))

    Science.gov (United States)

    Vanin, G.

    2012-06-01

    In this article the author reviews the major contributions that have been published on the origin of Western constellations. He puts these contributions to a strict criticism, based both on the most recent historiographic acquisitions and use of modern software. This approach deprives of any foundation the ideas proposed by Maunder, Ovenden, Roy, Gurshtein, still considered reliable by many of the nonspecialists and the audience of fans, while appropriately emphasizes the great news and great value, albeit with some reservations, of the studies recently undertaken on the subject by Bradley Schaefer.

  1. The origin of the western constellations (I). (Italian Title: Líorigine delle costellazioni occidentali (I parte))

    Science.gov (United States)

    Vanin, G.

    2012-04-01

    In this article the author reviews the major contributions that have been published on the origin of Western constellations. He puts these contributions to a strict criticism, based both on the most recent historiographic acquisitions and use of modern software. This approach deprives of any foundation the ideas proposed by Maunder, Ovenden, Roy, Gurshtein, still considered reliable by many of the nonspecialists and the audience of fans, while appropriately emphasizes the great news and great value, albeit with some reservations, of the studies recently undertaken on the subject by Bradley Schaefer.

  2. A dynamic globalization model for large eddy simulation of complex turbulent flow

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hae Cheon; Park, No Ma; Kim, Jin Seok [Seoul National Univ., Seoul (Korea, Republic of)

    2005-07-01

    A dynamic subgrid-scale model is proposed for large eddy simulation of turbulent flows in complex geometry. The eddy viscosity model by Vreman [Phys. Fluids, 16, 3670 (2004)] is considered as a base model. A priori tests with the original Vreman model show that it predicts the correct profile of subgrid-scale dissipation in turbulent channel flow but the optimal model coefficient is far from universal. Dynamic procedures of determining the model coefficient are proposed based on the 'global equilibrium' between the subgrid-scale dissipation and viscous dissipation. An important feature of the proposed procedures is that the model coefficient determined is globally constant in space but varies only in time. Large eddy simulations with the present dynamic model are conducted for forced isotropic turbulence, turbulent channel flow and flow over a sphere, showing excellent agreements with previous results.

  3. Renal artery origins: best angiographic projection angles.

    Science.gov (United States)

    Verschuyl, E J; Kaatee, R; Beek, F J; Patel, N H; Fontaine, A B; Daly, C P; Coldwell, D M; Bush, W H; Mali, W P

    1997-10-01

    To determine the best projection angles for imaging the renal artery origins in profile. A mathematical model of the anatomy at the renal artery origins in the transverse plane was used to analyze the amount of aortic lumen that projects over the renal artery origins at various projection angles. Computed tomographic (CT) angiographic data about the location of 400 renal artery origins in 200 patients were statistically analyzed. In patients with an abdominal aortic diameter no larger than 3.0 cm, approximately 0.5 mm of the proximal part of the renal artery and origin may be hidden from view if there is a projection error of +/-10 degrees from the ideal image. A combination of anteroposterior and 20 degrees and 40 degrees left anterior oblique projections resulted in a 92% yield of images that adequately profiled the renal artery origins. Right anterior oblique projections resulted in the least useful images. An error in projection angle of +/-10 degrees is acceptable for angiographic imaging of the renal artery origins. Patients sex, site of interest (left or right artery), and local diameter of the abdominal aorta are important factors to consider.

  4. On the origin of amplitude reduction mechanism in tapping mode atomic force microscopy

    Science.gov (United States)

    Keyvani, Aliasghar; Sadeghian, Hamed; Goosen, Hans; van Keulen, Fred

    2018-04-01

    The origin of amplitude reduction in Tapping Mode Atomic Force Microscopy (TM-AFM) is typically attributed to the shift in resonance frequency of the cantilever due to the nonlinear tip-sample interactions. In this paper, we present a different insight into the same problem which, besides explaining the amplitude reduction mechanism, provides a simple reasoning for the relationship between tip-sample interactions and operation parameters (amplitude and frequency). The proposed formulation, which attributes the amplitude reduction to an interference between the tip-sample and dither force, only deals with the linear part of the system; however, it fully agrees with experimental results and numerical solutions of the full nonlinear model of TM-AFM.

  5. Possible galactic origin of. gamma. -ray bursts

    Energy Technology Data Exchange (ETDEWEB)

    Manchanda, R K; Ramsden, D [Southampton Univ. (UK). Dept. of Physics

    1977-03-31

    It is stated that extragalactic models for the origin of non-solar ..gamma..-ray bursts include supernova bursts in remote galaxies, and the collapse of the cores of active stars, whilst galactic models are based on flare stars, thermonuclear explosions in neutron stars and the sudden accretion of cometary gas on to neutron stars. The acceptability of any of these models may be tested by the observed size spectrum of the ..gamma..-ray bursts. The extragalactic models predict a power law spectrum with number index -1.5, whilst for the galactic models the number index will be -1. Experimental data on ..gamma..-ray bursts is, however, still meagre, and so far only 44 confirmed events have been recorded by satellite-borne instruments. The number spectrum of the observed ..gamma..-ray bursts indicates that the observed distribution for events with an energy < 10/sup -4/ erg/cm/sup 2/ is flat; this makes the choice of any model completely arbitrary. An analysis of the observed ..gamma..-ray events is here presented that suggests very interesting possibilities for their origin. There appears to be a preferred mean energy for ..gamma..-ray bursts; some 90% of the recorded events show a mean energy between 5 x 10/sup -5/ and 5 x 10/sup -4/ erg/cm/sup 2/, contrary to the predicted characteristics of the number spectrum of various models. A remarkable similarity is found between the distribution of ..gamma..-ray bursts and that of supernova remnants, suggesting a genetic relationship between the two and the galactic origin of the ..gamma..-ray bursts, and the burst source could be identified with completely run down neutron stars, formed during supernova explosions.

  6. Origin of the earth and moon

    International Nuclear Information System (INIS)

    Ringwood, A.E.

    1981-01-01

    The composition of the Earth's interior and its bearing on the Earth's origin are discussed. It seems likely that the terrestrial planets formed by the accretion of solid planetisimals from the nebula of dust and gas left behind during the formation of the Sun. The scenario proposed is simpler than others. New evidence based upon a comparison of siderophile element abundances in the Earth's mantle and in the Moon imply that the Moon was derived from the Earth's mantle after the Earth's core had segregated

  7. Organizational intellectual capital and the role of the nurse manager: A proposed conceptual model.

    Science.gov (United States)

    Gilbert, Jason H; Von Ah, Diane; Broome, Marion E

    Nurse managers must leverage both the human capital and social capital of the teams they lead in order to produce quality outcomes. Little is known about the relationship between human capital and social capital and how these concepts may work together to produce organizational outcomes through leadership of nurses. The purpose of this article was to explore the concepts of human capital and social capital as they relate to nursing leadership in health care organizations. Specific aims included (a) to synthesize the literature related to human capital and social capital in leadership, (b) to refine the conceptual definitions of human capital and social capital with associated conceptual antecedents and consequences, and (c) to propose a synthesized conceptual model guiding further empirical research of social capital and human capital in nursing leadership. A systematic integrative review of leadership literature using criteria informed by Whittemore and Knafl (2005) was completed. CINAHL Plus with Full Text, Academic Search Premier, Business Source Premier, Health Business FullTEXT, MEDLINE, and PsychINFO databases were searched for the years 1995 to 2016 using terms "human capital," "social capital," and "management." Analysis of conceptual definitions, theoretical and conceptual models, antecedents and consequences, propositions or hypotheses, and empirical support for 37 articles fitting review criteria resulted in the synthesis of the proposed Gilbert Conceptual Model of Organizational Intellectual Capital. The Gilbert Conceptual Model of Organizational Intellectual Capital advances the propositions of human capital theory and social capital theory and is the first model to conceptualize the direct and moderating effects that nurse leaders have on the human capital and social capital of the teams they lead. This model provides a framework for further empirical study and may have implications for practice, organizational policy, and education related to nursing

  8. Constructive Approaches for Understanding the Origin of Self-Replication and Evolution

    Directory of Open Access Journals (Sweden)

    Norikazu Ichihashi

    2016-07-01

    Full Text Available The mystery of the origin of life can be divided into two parts. The first part is the origin of biomolecules: under what physicochemical conditions did biomolecules such as amino acids, nucleotides, and their polymers arise? The second part of the mystery is the origin of life-specific functions such as the replication of genetic information, the reproduction of cellular structures, metabolism, and evolution. These functions require the coordination of many different kinds of biological molecules. A direct strategy to approach the second part of the mystery is the constructive approach, in which life-specific functions are recreated in a test tube from specific biological molecules. Using this approach, we are able to employ design principles to reproduce life-specific functions, and the knowledge gained through the reproduction process provides clues as to their origins. In this mini-review, we introduce recent insights gained using this approach, and propose important future directions for advancing our understanding of the origins of life.

  9. Competence and the Evolutionary Origins of Status and Power in Humans.

    Science.gov (United States)

    Chapais, Bernard

    2015-06-01

    In this paper I propose an evolutionary model of human status that expands upon an earlier model proposed by Henrich and Gil-White Evolution and Human Behavior, 22,165-196 (2001). According to their model, there are two systems of status attainment in humans-"two ways to the top": the dominance route, which involves physical intimidation, a psychology of fear and hubristic pride, and provides coercive power, and the prestige route, which involves skills and knowledge (competence), a psychology of attraction to experts and authentic pride, and translates mainly into influence. The two systems would have evolved in response to different selective pressures, with attraction to experts serving a social learning function and coinciding with the evolution of cumulative culture. In this paper I argue that (1) the only one way to the top is competence because dominance itself involves competence and confers prestige, so there is no such thing as pure dominance status; (2) dominance in primates has two components: a competitive one involving physical coercion and a cooperative one involving competence-based attraction to high-ranking individuals (proto-prestige); (3) competence grants the same general type of power (dependence-based) in humans and other primates; (4) the attractiveness of high rank in primates is homologous with the admiration of experts in humans; (5) upon the evolution of cumulative culture, the attractiveness of high rank was co-opted to generate status differentials in a vast number of culturally generated domains of activity. I also discuss, in this perspective, the origins of hubristic pride, authentic pride, and nonauthoritarian leadership.

  10. Understanding original antigenic sin in influenza with a dynamical system.

    Science.gov (United States)

    Pan, Keyao

    2011-01-01

    Original antigenic sin is the phenomenon in which prior exposure to an antigen leads to a subsequent suboptimal immune response to a related antigen. Immune memory normally allows for an improved and rapid response to antigens previously seen and is the mechanism by which vaccination works. I here develop a dynamical system model of the mechanism of original antigenic sin in influenza, clarifying and explaining the detailed spin-glass treatment of original antigenic sin. The dynamical system describes the viral load, the quantities of healthy and infected epithelial cells, the concentrations of naïve and memory antibodies, and the affinities of naïve and memory antibodies. I give explicit correspondences between the microscopic variables of the spin-glass model and those of the present dynamical system model. The dynamical system model reproduces the phenomenon of original antigenic sin and describes how a competition between different types of B cells compromises the overall effect of immune response. I illustrate the competition between the naïve and the memory antibodies as a function of the antigenic distance between the initial and subsequent antigens. The suboptimal immune response caused by original antigenic sin is observed when the host is exposed to an antigen which has intermediate antigenic distance to a second antigen previously recognized by the host's immune system.

  11. Model of Local Sustainable Development in the Areas of Co-Occurrence Natura 2000 Sites and Non Energy Mining Industry (NEEI

    Directory of Open Access Journals (Sweden)

    Krzysztof Wrana

    2014-01-01

    Originality/value: The model presented is an original proposal. This is the first attempt, in Poland, to indicate a scenario approach to solving problems concerning the impact mining has on nature. The approach should be applied both at a national and local level.

  12. Virulence Studies of Different Sequence Types and Geographical Origins of Streptococcus suis Serotype 2 in a Mouse Model of Infection

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Auger

    2016-07-01

    Full Text Available Multilocus sequence typing previously identified three predominant sequence types (STs of Streptococcus suis serotype 2: ST1 strains predominate in Eurasia while North American (NA strains are generally ST25 and ST28. However, ST25/ST28 and ST1 strains have also been isolated in Asia and NA, respectively. Using a well-standardized mouse model of infection, the virulence of strains belonging to different STs and different geographical origins was evaluated. Results demonstrated that although a certain tendency may be observed, S. suis serotype 2 virulence is difficult to predict based on ST and geographical origin alone; strains belonging to the same ST presented important differences of virulence and did not always correlate with origin. The only exception appears to be NA ST28 strains, which were generally less virulent in both systemic and central nervous system (CNS infection models. Persistent and high levels of bacteremia accompanied by elevated CNS inflammation are required to cause meningitis. Although widely used, in vitro tests such as phagocytosis and killing assays require further standardization in order to be used as predictive tests for evaluating virulence of strains. The use of strains other than archetypal strains has increased our knowledge and understanding of the S. suis serotype 2 population dynamics.

  13. Deep Belief Network Based Hybrid Model for Building Energy Consumption Prediction

    Directory of Open Access Journals (Sweden)

    Chengdong Li

    2018-01-01

    Full Text Available To enhance the prediction performance for building energy consumption, this paper presents a modified deep belief network (DBN based hybrid model. The proposed hybrid model combines the outputs from the DBN model with the energy-consuming pattern to yield the final prediction results. The energy-consuming pattern in this study represents the periodicity property of building energy consumption and can be extracted from the observed historical energy consumption data. The residual data generated by removing the energy-consuming pattern from the original data are utilized to train the modified DBN model. The training of the modified DBN includes two steps, the first one of which adopts the contrastive divergence (CD algorithm to optimize the hidden parameters in a pre-train way, while the second one determines the output weighting vector by the least squares method. The proposed hybrid model is applied to two kinds of building energy consumption data sets that have different energy-consuming patterns (daily-periodicity and weekly-periodicity. In order to examine the advantages of the proposed model, four popular artificial intelligence methods—the backward propagation neural network (BPNN, the generalized radial basis function neural network (GRBFNN, the extreme learning machine (ELM, and the support vector regressor (SVR are chosen as the comparative approaches. Experimental results demonstrate that the proposed DBN based hybrid model has the best performance compared with the comparative techniques. Another thing to be mentioned is that all the predictors constructed by utilizing the energy-consuming patterns perform better than those designed only by the original data. This verifies the usefulness of the incorporation of the energy-consuming patterns. The proposed approach can also be extended and applied to some other similar prediction problems that have periodicity patterns, e.g., the traffic flow forecasting and the electricity consumption

  14. PTSD's latent structure in Malaysian tsunami victims: assessing the newly proposed Dysphoric Arousal model.

    Science.gov (United States)

    Armour, Cherie; Raudzah Ghazali, Siti; Elklit, Ask

    2013-03-30

    The underlying latent structure of Posttraumatic Stress Disorder (PTSD) is widely researched. However, despite a plethora of factor analytic studies, no single model has consistently been shown as superior to alternative models. The two most often supported models are the Emotional Numbing and the Dysphoria models. However, a recently proposed five-factor Dysphoric Arousal model has been gathering support over and above existing models. Data for the current study were gathered from Malaysian Tsunami survivors (N=250). Three competing models (Emotional Numbing/Dysphoria/Dysphoric Arousal) were specified and estimated using Confirmatory Factor Analysis (CFA). The Dysphoria model provided superior fit to the data compared to the Emotional Numbing model. However, using chi-square difference tests, the Dysphoric Arousal model showed a superior fit compared to both the Emotional Numbing and Dysphoria models. In conclusion, the current results suggest that the Dysphoric Arousal model better represents PTSD's latent structure and that items measuring sleeping difficulties, irritability/anger and concentration difficulties form a separate, unique PTSD factor. These results are discussed in relation to the role of Hyperarousal in PTSD's on-going symptom maintenance and in relation to the DSM-5. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Characterization Scheme for Property Prediction of Fluid Fractions Originating from Biomass

    DEFF Research Database (Denmark)

    Nguyen, Thanh-Binh; de Hemptinne, Jean-Charles; Creton, Benoit

    2015-01-01

    ) has been constructed, which contains a number of descriptors originating from analytical measurements. Using physical insight on the molecular interactions, an algorithm is proposed that uses five descriptors (molecular weight, liquid molar volume, viscosity, refractive index, and dielectric constant...

  16. Luminescence model with quantum impact parameter for low energy ions

    CERN Document Server

    Cruz-Galindo, H S; Martínez-Davalos, A; Belmont-Moreno, E; Galindo, S

    2002-01-01

    We have modified an analytical model of induced light production by energetic ions interacting in scintillating materials. The original model is based on the distribution of energy deposited by secondary electrons produced along the ion's track. The range of scattered electrons, and thus the energy distribution, depends on a classical impact parameter between the electron and the ion's track. The only adjustable parameter of the model is the quenching density rho sub q. The modification here presented, consists in proposing a quantum impact parameter that leads to a better fit of the model to the experimental data at low incident ion energies. The light output response of CsI(Tl) detectors to low energy ions (<3 MeV/A) is fitted with the modified model and comparison is made to the original model.

  17. Reconsidering the origins of the Southern African regionalism thirty years later: towards a constructivist approach to the origins of SADC

    Directory of Open Access Journals (Sweden)

    José Abel Moma

    2012-01-01

    Full Text Available The creation of SADCC has generated a debate over the real origins of the southern African model of regionalism. This paper develops the idea that the origins of SADC are both internal and external. Thus, southern African regionalism is understood as a constructivist articulation of internal and external inputs, which determined the creation of SADCC and its transformation into SADC.

  18. TOWARDS THE FORMULATION OF A PROPOSAL FOR OPPORTUNITY-TO-LEARN STANDARDS IN EFL LEARNING AND TEACHING

    Directory of Open Access Journals (Sweden)

    Rosalba Cárdenas Ramos

    2011-08-01

    Full Text Available This paper focuses on the need to formulate and implement a proposal for opportunity-to-learn standards (OTL in the field of language learning and teaching in Colombia, with the aim of ensuring the necessary conditions for the implementation and achievement of the performance standards, issued by the Ministry of Education as part of the National Bilingual Program in this area. First, it reviews the concept, origins, composition and models of OTL standards, and then it examines the Colombian situation to make a case for OTL in this country.

  19. Non-targeted volatile profiles for the classification of the botanical origin of Chinese honey by solid-phase microextraction and gas chromatography-mass spectrometry combined with chemometrics.

    Science.gov (United States)

    Chen, Hui; Jin, Linghe; Fan, Chunlin; Wang, Wenwen

    2017-11-01

    A potential method for the discrimination and prediction of honey samples of various botanical origins was developed based on the non-targeted volatile profiles obtained by solid-phase microextraction with gas chromatography and mass spectrometry combined with chemometrics. The blind analysis of non-targeted volatile profiles was carried out using solid-phase microextraction with gas chromatography and mass spectrometry for 87 authentic honey samples from four botanical origins (acacia, linden, vitex, and rape). The number of variables was reduced from 2734 to 70 by using a series of filters. Based on the optimized 70 variables, 79.12% of the variance was explained by the first four principal components. Partial least squares discriminant analysis, naïve Bayes analysis, and back-propagation artificial neural network were used to develop the classification and prediction models. The 100% accuracy revealed a perfect classification of the botanical origins. In addition, the reliability and practicability of the models were validated by an independent set of additional 20 authentic honey samples. All 20 samples were accurately classified. The confidence measures indicated that the performance of the naïve Bayes model was better than the other two models. Finally, the characteristic volatile compounds of linden honey were tentatively identified. The proposed method is reliable and accurate for the classification of honey of various botanical origins. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. The 'model omnitron' proposed experiment

    International Nuclear Information System (INIS)

    Sestero, A.

    1997-05-01

    The Model Omitron is a compact tokamak experiment which is designed by the Fusion Engineering Unit of ENEA and CITIF CONSORTIUM. The building of Model Omitron would allow for full testing of Omitron engineering, and partial testing of Omitron physics -at about 1/20 of the cost that has been estimated for the larger parent machine. In particular, due to the unusually large ohmic power densities (up to 100 times the nominal value in the Frascati FTU experiment), in Model Omitron the radial energy flux is reaching values comparable or higher than envisaged of the larger ignition experiments Omitron, Ignitor and Iter. Consequently, conditions are expected to occur at the plasma border in the scrape-off layer of Model Omitron, which are representative of the quoted larger experiments. Moreover, since all this will occur under ohmic heating alone, one will hopefully be able to derive an energy transport model fo the ohmic heating regime that is valid over a range of plasma parameters (in particular, of the temperature parameter) wider than it was possible before. In the Model Omitron experiment, finally - by reducing the plasma current and/or the toroidal field down to, say, 1/3 or 1/4 of the nominal values -additional topics can be tackled, such as: large safety-factor configurations (of interest for improving confinement), large aspect-ratio configurations (of interest for the investigation of advanced concepts in tokamaks), high beta (with RF heating -also of interest for the investigation of advanced concepts in tokamaks), long pulse discharges (of interest for demonstrating stationary conditions in the current profile)

  1. Equation-based model for the stock market.

    Science.gov (United States)

    Xavier, Paloma O C; Atman, A P F; de Magalhães, A R Bosco

    2017-09-01

    We propose a stock market model which is investigated in the forms of difference and differential equations whose variables correspond to the demand or supply of each agent and to the price. In the model, agents are driven by the behavior of their trust contact network as well by fundamental analysis. By means of the deterministic version of the model, the connection between such drive mechanisms and the price is analyzed: imitation behavior promotes market instability, finitude of resources is associated to stock index stability, and high sensitivity to the fair price provokes price oscillations. Long-range correlations in the price temporal series and heavy-tailed distribution of returns are observed for the version of the model which considers different proposals for stochasticity of microeconomic and macroeconomic origins.

  2. Equation-based model for the stock market

    Science.gov (United States)

    Xavier, Paloma O. C.; Atman, A. P. F.; de Magalhães, A. R. Bosco

    2017-09-01

    We propose a stock market model which is investigated in the forms of difference and differential equations whose variables correspond to the demand or supply of each agent and to the price. In the model, agents are driven by the behavior of their trust contact network as well by fundamental analysis. By means of the deterministic version of the model, the connection between such drive mechanisms and the price is analyzed: imitation behavior promotes market instability, finitude of resources is associated to stock index stability, and high sensitivity to the fair price provokes price oscillations. Long-range correlations in the price temporal series and heavy-tailed distribution of returns are observed for the version of the model which considers different proposals for stochasticity of microeconomic and macroeconomic origins.

  3. The multiregional and single origin hypotheses of the evolution of modern man: a reconciliation.

    Science.gov (United States)

    Treisman, M

    1995-03-07

    A current debate opposes two theories of the origin of modern man. One view is that modern Homo sapiens emerged from Africa relatively recently, most probably within the last two or three hundred thousand years (Wilson & Cann, 1992, Sci. Am. 266(4), 22-27). The opposing view is that modern man has resulted from parallel evolution in different regions, producing convergent modernization of local populations over the last million years or so--the multiregional model (Frayer et al., 1993, Am. Anthrop. 95, 14-50). Proponents of both views believe that their interpretations are irreconcilable. The object of the present paper is to describe a genetic mechanism--mitochondrial exclusion--which offers a basis for a model of human evolution that is compatible with the evidence adduced for both contemporary views. The model proposes a mechanism by which complete replacement of archaic mitochondrial DNA may have occurred in a population produced by recent admixture of archaic and modern types of man.

  4. The 2012 dengue outbreak in Madeira: exploring the origins.

    Science.gov (United States)

    Wilder-Smith, A; Quam, M; Sessions, O; Rocklov, J; Liu-Helmersson, J; Franco, L; Khan, K

    2014-02-27

    In 2012, Madeira reported its first major outbreak of dengue. To identify the origin of the imported dengue virus, we investigated the interconnectivity via air travel between dengue-endemic countries and Madeira, and compared available sequences against GenBank. There were 22,948 air travellers to Madeira in 2012, originating from twenty-nine dengue-endemic countries; 89.6% of these international travellers originated from Venezuela and Brazil. We developed an importation index that takes into account both travel volume and the extent of dengue incidence in the country of origin. Venezuela and Brazil had by far the highest importation indices compared with all other dengue-endemic countries. The importation index for Venezuela was twice as high as that for Brazil. When taking into account seasonality in the months preceding the onset of the Madeira outbreak, this index was even seven times higher for Venezuela than for Brazil during this time. Dengue sequencing shows that the virus responsible for the Madeira outbreak was most closely related to viruses circulating in Venezuela, Brazil and Columbia. Applying the importation index, Venezuela was identified as the most likely origin of importation of dengue virus via travellers to Madeira. We propose that the importation index is a new additional tool that can help to identify and anticipate the most probable country of origin for importation of dengue into currently non-endemic countries.

  5. Origins of Life: Open Questions and Debates

    Science.gov (United States)

    Brack, André

    2017-10-01

    Stanley Miller demonstrated in 1953 that it was possible to form amino acids from methane, ammonia, and hydrogen in water, thus launching the ambitious hope that chemists would be able to shed light on the origins of life by recreating a simple life form in a test tube. However, it must be acknowledged that the dream has not yet been accomplished, despite the great volume of effort and innovation put forward by the scientific community. A minima, primitive life can be defined as an open chemical system, fed with matter and energy, capable of self-reproduction (i.e., making more of itself by itself), and also capable of evolving. The concept of evolution implies that chemical systems would transfer their information fairly faithfully but make some random errors. If we compared the components of primitive life to parts of a chemical automaton, we could conceive that, by chance, some parts self-assembled to generate an automaton capable of assembling other parts to produce a true copy. Sometimes, minor errors in the building generated a more efficient automaton, which then became the dominant species. Quite different scenarios and routes have been followed and tested in the laboratory to explain the origin of life. There are two schools of thought in proposing the prebiotic supply of organics. The proponents of a metabolism-first call for the spontaneous formation of simple molecules from carbon dioxide and water to rapidly generate life. In a second hypothesis, the primeval soup scenario, it is proposed that rather complex organic molecules accumulated in a warm little pond prior to the emergence of life. The proponents of the primeval soup or replication first approach are by far the more active. They succeeded in reconstructing small-scale versions of proteins, membranes, and RNA. Quite different scenarios have been proposed for the inception of life: the RNA world, an origin within droplets, self-organization counteracting entropy, or a stochastic approach merging

  6. Model Correction Factor Method

    DEFF Research Database (Denmark)

    Christensen, Claus; Randrup-Thomsen, Søren; Morsing Johannesen, Johannes

    1997-01-01

    The model correction factor method is proposed as an alternative to traditional polynomial based response surface techniques in structural reliability considering a computationally time consuming limit state procedure as a 'black box'. The class of polynomial functions is replaced by a limit...... of the model correction factor method, is that in simpler form not using gradient information on the original limit state function or only using this information once, a drastic reduction of the number of limit state evaluation is obtained together with good approximations on the reliability. Methods...

  7. The origin of neutrino mass: Stations along the path of cognition

    International Nuclear Information System (INIS)

    Minkowski, Peter

    2009-01-01

    I propose to give an outline based on partial answers to questions beneath 'the origin of neutrino mass': (a) building on the limiting uncurved structure of 1 time + 3 space dimensions, what is the full extent of space-time dimensions and their meaning in quantum gravity? (b) what is the origin and nature of spin- 1/2 fermions? (c) if charge-like and orientation-like gaugeing is related, then what is the explanation for 3 colors and 3 families along the path of unification?

  8. The social networking application success model : An empirical study of Facebook and Twitter

    NARCIS (Netherlands)

    Ou, Carol; Davison, R.M.; Huang, Q.

    2016-01-01

    Social networking applications (SNAs) are among the fastest growing web applications of recent years. In this paper, we propose a causal model to assess the success of SNAs, grounded on DeLone and McLean’s updated information systems (IS) success model. In addition to their original three dimensions

  9. Original antigenic sin: A comprehensive review.

    Science.gov (United States)

    Vatti, Anup; Monsalve, Diana M; Pacheco, Yovana; Chang, Christopher; Anaya, Juan-Manuel; Gershwin, M Eric

    2017-09-01

    The concept of "original antigenic sin" was first proposed by Thomas Francis, Jr. in 1960. This phenomenon has the potential to rewrite what we understand about how the immune system responds to infections and its mechanistic implications on how vaccines should be designed. Antigenic sin has been demonstrated to occur in several infectious diseases in both animals and humans, including human influenza infection and dengue fever. The basis of "original antigenic sin" requires immunological memory, and our immune system ability to autocorrect. In the context of viral infections, it is expected that if we are exposed to a native strain of a pathogen, we should be able to mount a secondary immune response on subsequent exposure to the same pathogen. "Original antigenic sin" will not contradict this well-established immunological process, as long as the subsequent infectious antigen is identical to the original one. But "original antigenic sin" implies that when the epitope varies slightly, then the immune system relies on memory of the earlier infection, rather than mount another primary or secondary response to the new epitope which would allow faster and stronger responses. The result is that the immunological response may be inadequate against the new strain, because the immune system does not adapt and instead relies on its memory to mount a response. In the case of vaccines, if we only immunize to a single strain or epitope, and if that strain/epitope changes over time, then the immune system is unable to mount an accurate secondary response. In addition, depending of the first viral exposure the secondary immune response can result in an antibody-dependent enhancement of the disease or at the opposite, it could induce anergy. Both of them triggering loss of pathogen control and inducing aberrant clinical consequences. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Distributional patterns and possible origin of leafhoppers (Homoptera, Cicadellidae

    Directory of Open Access Journals (Sweden)

    Mervin W. Nielson

    2000-03-01

    Full Text Available The zoogeographical distribution of 42 cicadellid subfamilies and their assigned tribes and genera is compiled with distributional maps and proposed dispersal pathways of genera that are shared interzoogeographically. Possible origin of the subfamilies and tribes is proposed in an ancestral context from which the more modern extant groups evolved whereas origin of genera is in a more modern context. Notwithstanding their complex biogeography, the distributional data of the higher groups indicate that all of the cosmopolitan and near cosmopolitan subfamilies arose during early Cretaceous or possibly the late Jurassic period (140-116 m.y.a. when continental drift was in its early stages. Nearly all of the New World and some Old World subfamilies are considered of more recent origin (late Cretaceous-Tertiary. Ninety percent of the known genera (2,126 are endemic to their respective zoogeographical region and subregion, thus indicating relatively high host specificity and low rate of dispersal. The majority (76% of known extant genera are pantropical in origin, suggesting early or possible Gondwanaland origin of their ancestors. Dispersal pathways of genera shared by more than one zoogeographical region were generally south to north (Neotropical/Nearctic, Oriental/Palaearctic or west to east (Palaearctic/Nearctic, Oriental/Australian, from regions of high diversity to regions of low diversity and from warmer climates to cooler climates. The most diverse and richest leafhopper fauna are present in the Neotropical and Ethiopian regions although taxal affinities between them are poorest. The most depauperate fauna are in the Nearctic region and in Australia, reflecting the impact of isolating and ecological factors on distribution and radiation. Ecological barriers were more evident between the Ethiopian and Oriental fauna than between any other zoogeographical combination. Taxal affinities appeared to be correlated with close continental proximities

  11. Origins and consequences of technology acquirement by independent-living seniors: towards an integrative model.

    Science.gov (United States)

    Peek, S T M; Luijkx, K G; Vrijhoef, H J M; Nieboer, M E; Aarts, S; van der Voort, C S; Rijnaard, M D; Wouters, E J M

    2017-08-22

    Living independently can be challenging for seniors. Technologies are expected to help older adults age in place, yet little empirical research is available on how seniors develop a need for technologies, how they acquire these technologies, and how these subsequently affect their lives. Aging is complex, dynamic and personal. But how does this translate to seniors' adoption and acceptance of technology? To better understand origins and consequences of technology acquirement by independent-living seniors, an explorative longitudinal qualitative field study was set up. Home visits were made to 33 community-dwelling seniors living in the Netherlands, on three occasions (2012-2014). Semi-structured interviews were conducted on the timeline of acquirements, and people and factors involved in acquirements. Additionally, participants were interviewed on experiences in using technologies since acquirement. Thematic analysis was employed to analyze interview transcripts, using a realist approach to better understand the contexts, mechanisms and outcomes of technology acquirements. Findings were accumulated in a new conceptual model: The Cycle of Technology Acquirement by Independent-Living Seniors (C-TAILS), which provides an integrative perspective on why and how technologies are acquired, and why these may or may not prove to be appropriate and effective, considering an independent-living senior's needs and circumstances at a given point in time. We found that externally driven and purely desire-driven acquirements led to a higher risk of suboptimal use and low levels of need satisfaction. Technology acquirement by independent-living seniors may be best characterized as a heterogeneous process with many different origins, pathways and consequences. Furthermore, technologies that are acquired in ways that are not congruent with seniors' personal needs and circumstances run a higher risk of proving to be ineffective or inappropriate. Yet, these needs and circumstances are

  12. Vehicle logo recognition using multi-level fusion model

    Science.gov (United States)

    Ming, Wei; Xiao, Jianli

    2018-04-01

    Vehicle logo recognition plays an important role in manufacturer identification and vehicle recognition. This paper proposes a new vehicle logo recognition algorithm. It has a hierarchical framework, which consists of two fusion levels. At the first level, a feature fusion model is employed to map the original features to a higher dimension feature space. In this space, the vehicle logos become more recognizable. At the second level, a weighted voting strategy is proposed to promote the accuracy and the robustness of the recognition results. To evaluate the performance of the proposed algorithm, extensive experiments are performed, which demonstrate that the proposed algorithm can achieve high recognition accuracy and work robustly.

  13. A Review of Ideas Concerning Life Origin

    Science.gov (United States)

    Gindilis, L. M.

    2014-10-01

    of prebiotic evolution products. The quantitative model he has brought forward increases life origination probability by many orders of magnitude in comparison with any isolated planet. In this model the life to originates simultaneously on all the planets with proper conditions on the same molecular basis, one and the same genetic code and the same chirality.

  14. Global model of zenith tropospheric delay proposed based on EOF analysis

    Science.gov (United States)

    Sun, Langlang; Chen, Peng; Wei, Erhu; Li, Qinzheng

    2017-07-01

    Tropospheric delay is one of the main error budgets in Global Navigation Satellite System (GNSS) measurements. Many empirical correction models have been developed to compensate this delay, and models which do not require meteorological parameters have received the most attention. This study established a global troposphere zenith total delay (ZTD) model, called Global Empirical Orthogonal Function Troposphere (GEOFT), based on the empirical orthogonal function (EOF, also known as geographically weighted PCAs) analysis method and the Global Geodetic Observing System (GGOS) Atmosphere data from 2012 to 2015. The results showed that ZTD variation could be well represented by the characteristics of the EOF base function Ek and associated coefficients Pk. Here, E1 mainly signifies the equatorial anomaly; E2 represents north-south asymmetry, and E3 and E4 reflects regional variation. Moreover, P1 mainly reflects annual and semiannual variation components; P2 and P3 mainly contains annual variation components, and P4 displays semiannual variation components. We validated the proposed GEOFT model using tropospheric delay data of GGOS ZTD grid data and the tropospheric product of the International GNSS Service (IGS) over the year 2016. The results showed that GEOFT model has high accuracy with bias and RMS of -0.3 and 3.9 cm, respectively, with respect to the GGOS ZTD data, and of -0.8 and 4.1 cm, respectively, with respect to the global IGS tropospheric product. The accuracy of GEOFT demonstrating that the use of the EOF analysis method to characterize ZTD variation is reasonable.

  15. Autosomal STRs provide genetic evidence for the hypothesis that Tai people originate from southern China.

    Directory of Open Access Journals (Sweden)

    Hao Sun

    Full Text Available Tai people are widely distributed in Thailand, Laos and southwestern China and are a large population of Southeast Asia. Although most anthropologists and historians agree that modern Tai people are from southwestern China and northern Thailand, the place from which they historically migrated remains controversial. Three popular hypotheses have been proposed: northern origin hypothesis, southern origin hypothesis or an indigenous origin. We compared the genetic relationships between the Tai in China and their "siblings" to test different hypotheses by analyzing 10 autosomal microsatellites. The genetic data of 916 samples from 19 populations were analyzed in this survey. The autosomal STR data from 15 of the 19 populations came from our previous study (Lin et al., 2010. 194 samples from four additional populations were genotyped in this study: Han (Yunnan, Dai (Dehong, Dai (Yuxi and Mongolian. The results of genetic distance comparisons, genetic structure analyses and admixture analyses all indicate that populations from northern origin hypothesis have large genetic distances and are clearly differentiated from the Tai. The simulation-based ABC analysis also indicates this. The posterior probability of the northern origin hypothesis is just 0.04 [95%CI: (0.01-0.06]. Conversely, genetic relationships were very close between the Tai and populations from southern origin or an indigenous origin hypothesis. Simulation-based ABC analyses were also used to distinguish the southern origin hypothesis from the indigenous origin hypothesis. The results indicate that the posterior probability of the southern origin hypothesis [0.640, 95%CI: (0.524-0.757] is greater than that of the indigenous origin hypothesis [0.324, 95%CI: (0.211-0.438]. Therefore, we propose that the genetic evidence does not support the hypothesis of northern origin. Our genetic data indicate that the southern origin hypothesis has higher probability than the other two hypotheses

  16. Origins of tiny neutrino mass and large flavor mixings

    International Nuclear Information System (INIS)

    Haba, Naoyuki

    2015-01-01

    Active neutrino masses are extremely smaller than those of other quarks and leptons, and there are large flavor mixings in the lepton sector, contrary to the quark sector. They are great mysteries in the standard model, but also excellent hints of new physics beyond the standard model. Thus, questions 'What is an origin of tiny neutrino mass?' and 'What is an origin of large lepton flavor mixings?' are very important. In this paper, we overview various attempts to solve these big questions. (author)

  17. The New Digital Media Value Network: Proposing an Interactive Model of Digital Media Value Activities

    Directory of Open Access Journals (Sweden)

    Sylvia Chan-Olmsted

    2016-07-01

    Full Text Available This study models the dynamic nature of today’s media markets using the framework of value-adding activities in the provision and consumption of media products. The proposed user-centric approach introduces the notion that the actions of external users, social media, and interfaces affect the internal value activities of media firms via a feedback loop, and therefore should themselves be considered value activities. The model also suggests a more comprehensive list of indicators for value assessment.

  18. Energetic models: a proposal of integrated planning; Modelos energeticos: uma proposta de planejamento integrado

    Energy Technology Data Exchange (ETDEWEB)

    Pereira Junior, Amaro Olimpio; Soares, Jeferson Borghetti; Araujo, Mauro Almeida [Empresa de Pesquisa Energetica (EPE), Brasilia, DF (Brazil)]. E-mails: amaro.pereira@epe.gov.br; jeferson.soares@epe.gov.br; mauro.almeida@epe.gov.br; La Rovere, Emilio Lebre [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Planejamento Estrategico]. E-mail: emilio@ppe.ufrj.br; Costa, Ricardo Cunha da [Banco Nacional de Desenvolvimento Economico e Social (BNDES), Rio de Janeiro, RJ (Brazil)]. E-mail: rcco@bndes.gov.br

    2006-07-01

    Top-down, bottom-up and hybrid models for representing energy system are often used in energy planning. However, in developing countries some of their assumptions do not apply: markets are not developed and not competitive; informal economies are representative; there are huge social inequalities; regulatory changes are not completed; there exist constraints to capital flow; etc. All theses problems need to be well represented in order to have energy analysis more consistent. In this work, it is proposed a multi-sector dynamic recursive model that incorporates consumer behaviors, energy policies, technical progress and factors of production substitution. The static result feeds detailed energy models that provide updated values for the next step equilibrium. This approach takes advantages not only in terms of computation but also in terms of the consistence between economy and energy modeling. (author)

  19. Uniting sex and eukaryote origins in an emerging oxygenic world.

    Science.gov (United States)

    Gross, Jeferson; Bhattacharya, Debashish

    2010-08-23

    Theories about eukaryote origins (eukaryogenesis) need to provide unified explanations for the emergence of diverse complex features that define this lineage. Models that propose a prokaryote-to-eukaryote transition are gridlocked between the opposing "phagocytosis first" and "mitochondria as seed" paradigms, neither of which fully explain the origins of eukaryote cell complexity. Sex (outcrossing with meiosis) is an example of an elaborate trait not yet satisfactorily addressed in theories about eukaryogenesis. The ancestral nature of meiosis and its dependence on eukaryote cell biology suggest that the emergence of sex and eukaryogenesis were simultaneous and synergic and may be explained by a common selective pressure. We propose that a local rise in oxygen levels, due to cyanobacterial photosynthesis in ancient Archean microenvironments, was highly toxic to the surrounding biota. This selective pressure drove the transformation of an archaeal (archaebacterial) lineage into the first eukaryotes. Key is that oxygen might have acted in synergy with environmental stresses such as ultraviolet (UV) radiation and/or desiccation that resulted in the accumulation of reactive oxygen species (ROS). The emergence of eukaryote features such as the endomembrane system and acquisition of the mitochondrion are posited as strategies to cope with a metabolic crisis in the cell plasma membrane and the accumulation of ROS, respectively. Selective pressure for efficient repair of ROS/UV-damaged DNA drove the evolution of sex, which required cell-cell fusions, cytoskeleton-mediated chromosome movement, and emergence of the nuclear envelope. Our model implies that evolution of sex and eukaryogenesis were inseparable processes. Several types of data can be used to test our hypothesis. These include paleontological predictions, simulation of ancient oxygenic microenvironments, and cell biological experiments with Archaea exposed to ROS and UV stresses. Studies of archaeal conjugation

  20. A Proposal of New Spherical Particle Modeling Method Based on Stochastic Sampling of Particle Locations in Monte Carlo Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Song Hyun; Kim, Do Hyun; Kim, Jong Kyung [Hanyang Univ., Seoul (Korea, Republic of); Noh, Jea Man [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    To the high computational efficiency and user convenience, the implicit method had received attention; however, it is noted that the implicit method in the previous studies has low accuracy at high packing fraction. In this study, a new implicit method, which can be used at any packing fraction with high accuracy, is proposed. In this study, the implicit modeling method in the spherical particle distributed medium for using the MC simulation is proposed. A new concept in the spherical particle sampling was developed to solve the problems in the previous implicit methods. The sampling method was verified by simulating the sampling method in the infinite and finite medium. The results show that the particle implicit modeling with the proposed method was accurately performed in all packing fraction boundaries. It is expected that the proposed method can be efficiently utilized for the spherical particle distributed mediums, which are the fusion reactor blanket, VHTR reactors, and shielding analysis.

  1. Methodology Using MELCOR Code to Model Proposed Hazard Scenario

    Energy Technology Data Exchange (ETDEWEB)

    Gavin Hawkley

    2010-07-01

    This study demonstrates a methodology for using the MELCOR code to model a proposed hazard scenario within a building containing radioactive powder, and the subsequent evaluation of a leak path factor (LPF) (or the amount of respirable material which that escapes a facility into the outside environment), implicit in the scenario. This LPF evaluation will analyzes the basis and applicability of an assumed standard multiplication of 0.5 × 0.5 (in which 0.5 represents the amount of material assumed to leave one area and enter another), for calculating an LPF value. The outside release is dependsent upon the ventilation/filtration system, both filtered and un-filtered, and from other pathways from the building, such as doorways (, both open and closed). This study is presents ed to show how the multiple leak path factorsLPFs from the interior building can be evaluated in a combinatory process in which a total leak path factorLPF is calculated, thus addressing the assumed multiplication, and allowing for the designation and assessment of a respirable source term (ST) for later consequence analysis, in which: the propagation of material released into the environmental atmosphere can be modeled and the dose received by a receptor placed downwind can be estimated and the distance adjusted to maintains such exposures as low as reasonably achievableALARA.. Also, this study will briefly addresses particle characteristics thatwhich affect atmospheric particle dispersion, and compares this dispersion with leak path factorLPF methodology.

  2. The Country of Origin Effect

    DEFF Research Database (Denmark)

    Hu, Lala; Baldin, Andrea

    2018-01-01

    The purpose of this paper is to analyse the country of origin (COO) effect on wine purchase in China by considering a sample from an e-commerce website. The paper contribute to the literature on hedonic pricing by applying this model to the Chinese market and including COO as product attribute....

  3. The use of synthetic input sequences in time series modeling

    International Nuclear Information System (INIS)

    Oliveira, Dair Jose de; Letellier, Christophe; Gomes, Murilo E.D.; Aguirre, Luis A.

    2008-01-01

    In many situations time series models obtained from noise-like data settle to trivial solutions under iteration. This Letter proposes a way of producing a synthetic (dummy) input, that is included to prevent the model from settling down to a trivial solution, while maintaining features of the original signal. Simulated benchmark models and a real time series of RR intervals from an ECG are used to illustrate the procedure

  4. Proposing a Qualitative Approach for Corporate Competitive Capability Modeling in High-Tech Business (Case study: Software Industry

    Directory of Open Access Journals (Sweden)

    Mahmoud Saremi Saremi

    2010-09-01

    Full Text Available The evolution of global business trend for ICT-based products in recent decades shows the intensive activity of pioneer developing countries to gain a powerful competitive position in global software industry. In this research, with regard to importance of competition issue for top managers of Iranian software companies, a conceptual model has been developed for Corporate Competitive Capability concept. First, after describing the research problem, we present a comparative review of recent theories of firm and competition that has been applied by different researchers in the High-Tech and Knowledge Intensive Organization filed. Afterwards, with a detailed review of literature and previous research papers, an initial research framework and applied research method has been proposed. The main and final section of paper assigned to describing the result of research in different steps of qualitative modeling process. The agreed concepts are related to corporate competitive capability, the elicited and analyzed experts Cause Map, the elicited collective causal maps, and the final proposed model for software industry are the modeling results for this paper.

  5. Automatic Generation of Symbolic Model for Parameterized Synchronous Systems

    Institute of Scientific and Technical Information of China (English)

    Wei-Wen Xu

    2004-01-01

    With the purpose of making the verification of parameterized system more general and easier, in this paper, a new and intuitive language PSL (Parameterized-system Specification Language) is proposed to specify a class of parameterized synchronous systems. From a PSL script, an automatic method is proposed to generate a constraint-based symbolic model. The model can concisely symbolically represent the collections of global states by counting the number of processes in a given state. Moreover, a theorem has been proved that there is a simulation relation between the original system and its symbolic model. Since the abstract and symbolic techniques are exploited in the symbolic model, state-explosion problem in traditional verification methods is efficiently avoided. Based on the proposed symbolic model, a reachability analysis procedure is implemented using ANSI C++ on UNIX platform. Thus, a complete tool for verifying the parameterized synchronous systems is obtained and tested for some cases. The experimental results show that the method is satisfactory.

  6. Telecommuting for Original Cataloging at the Michigan State University Libraries.

    Science.gov (United States)

    Black, Leah; Hyslop, Colleen

    1995-01-01

    Working conditions in library technical services departments can be a problem for catalogers in need of a quiet work environment. Based on a successful program for indexers at the National Agriculture Library, a proposal for an experimental telecommuting program for original cataloging at the Michigan State University Libraries was developed and…

  7. Noncoding origins of anthropoid traits and a new null model of transposon functionalization.

    Science.gov (United States)

    del Rosario, Ricardo C H; Rayan, Nirmala Arul; Prabhakar, Shyam

    2014-09-01

    Little is known about novel genetic elements that drove the emergence of anthropoid primates. We exploited the sequencing of the marmoset genome to identify 23,849 anthropoid-specific constrained (ASC) regions and confirmed their robust functional signatures. Of the ASC base pairs, 99.7% were noncoding, suggesting that novel anthropoid functional elements were overwhelmingly cis-regulatory. ASCs were highly enriched in loci associated with fetal brain development, motor coordination, neurotransmission, and vision, thus providing a large set of candidate elements for exploring the molecular basis of hallmark primate traits. We validated ASC192 as a primate-specific enhancer in proliferative zones of the developing brain. Unexpectedly, transposable elements (TEs) contributed to >56% of ASCs, and almost all TE families showed functional potential similar to that of nonrepetitive DNA. Three L1PA repeat-derived ASCs displayed coherent eye-enhancer function, thus demonstrating that the "gene-battery" model of TE functionalization applies to enhancers in vivo. Our study provides fundamental insights into genome evolution and the origins of anthropoid phenotypes and supports an elegantly simple new null model of TE exaptation. © 2014 del Rosario et al.; Published by Cold Spring Harbor Laboratory Press.

  8. A Developmental-Contextual Model of Depressive Symptoms in Mexican-Origin Female Adolescents

    Science.gov (United States)

    Bámaca-Colbert, Mayra Y.; Umaña-Taylor, Adriana J.; Gayles, Jochebed G.

    2011-01-01

    The current study tested a developmental-contextual model of depressive symptomatology among early and middle adolescent Mexican-origin females and their mothers. The final sample was comprised of 271 dyads. We examined the interrelations among cultural (i.e., acculturation dissonance), developmental (i.e., pubertal development and autonomy expectation discrepancies), and interpersonal (i.e., mother-daughter conflict and maternal supportive parenting) factors in predicting adolescents’ depressive symptoms. For both early and middle adolescents, maternal support was negatively associated with mother-daughter conflict and depressive symptoms. Importantly, mother-daughter autonomy expectation discrepancies were positively associated with mother-daughter conflict, but this association was found only among early adolescents. Further, mother-daughter acculturation dissonance was positively associated with mother-daughter conflict, but only among middle adolescents. Findings call for concurrently examining the interface of developmental, relational, and cultural factors in predicting female adolescents’ depressive symptomatology and the potential differences by developmental stage (e.g., early vs. middle adolescence) PMID:21967564

  9. The Standard Model Higgs as the origin of the hot Big Bang

    CERN Document Server

    Figueroa, Daniel G.

    2017-04-10

    If the Standard Model (SM) Higgs is weakly coupled to the inflationary sector, the Higgs is expected to be universally in the form of a condensate towards the end of inflation. The Higgs decays rapidly after inflation -- via non-perturbative effects -- into an out-of-equilibrium distribution of SM species, which thermalize soon afterwards. If the post-inflationary equation of state of the universe is stiff, $w \\simeq +1$, the SM species eventually dominate the total energy budget. This provides a natural origin for the relativistic thermal plasma of SM species, required for the onset the `hot Big Bang' era. The viability of this scenario requires the inflationary Hubble scale $H_*$ to be lower than the instability scale for Higgs vacuum decay, the Higgs not to generate too large curvature perturbations at cosmological scales, and the SM dominance to occur before Big Bang Nucleosynthesis. We show that successful reheating into the SM can only be obtained in the presence of a non-minimal coupling to gravity $\\x...

  10. The Physical Origin of Galaxy Morphologies and Scaling Laws

    Science.gov (United States)

    Steinmetz, Matthias; Navarro, Julio F.

    2002-01-01

    We propose a numerical study designed to interpret the origin and evolution of galaxy properties revealed by space- and ground-based imaging and spectroscopical surveys. Our aim is to unravel the physical processes responsible for the development of different galaxy morphologies and for the establishment of scaling laws such as the Tully-Fisher relation for spirals and the Fundamental Plane of ellipticals. In particular, we plan to address the following major topics: (1) The morphology and observability of protogalaxies, and in particular the relationship between primordial galaxies and the z approximately 3 'Ly-break' systems identified in the Hubble Deep Field and in ground-based searches; (2) The origin of the disk and spheroidal components in galaxies, the timing and mode of their assembly, the corresponding evolution in galaxy morphologies and its sensitivity to cosmological parameters; (3) The origin and redshift evolution of the scaling laws that link the mass, luminosity size, stellar content, and metal abundances of galaxies of different morphological types. This investigation will use state-of-the-art N-body/gasdynamical codes to provide a spatially resolved description of the galaxy formation process in hierarchically clustering universes. Coupled with population synthesis techniques. our models can be used to provide synthetic 'observations' that can be compared directly with observations of galaxies both nearby and at cosmologically significant distances. This study will thus provide insight into the nature of protogalaxies and into the formation process of galaxies like our own Milky Way. It will also help us to assess the cosmological significance of these observations within the context of hierarchical theories of galaxy formation and will supply a theoretical context within which current and future observations can be interpreted.

  11. Infinite Multiple Membership Relational Modeling for Complex Networks

    DEFF Research Database (Denmark)

    Mørup, Morten; Schmidt, Mikkel Nørgaard; Hansen, Lars Kai

    Learning latent structure in complex networks has become an important problem fueled by many types of networked data originating from practically all fields of science. In this paper, we propose a new non-parametric Bayesian multiplemembership latent feature model for networks. Contrary to existing...... multiplemembership models that scale quadratically in the number of vertices the proposedmodel scales linearly in the number of links admittingmultiple-membership analysis in large scale networks. We demonstrate a connection between the single membership relational model and multiple membership models and show...

  12. Research and Application of a Hybrid Forecasting Model Based on Data Decomposition for Electrical Load Forecasting

    Directory of Open Access Journals (Sweden)

    Yuqi Dong

    2016-12-01

    Full Text Available Accurate short-term electrical load forecasting plays a pivotal role in the national economy and people’s livelihood through providing effective future plans and ensuring a reliable supply of sustainable electricity. Although considerable work has been done to select suitable models and optimize the model parameters to forecast the short-term electrical load, few models are built based on the characteristics of time series, which will have a great impact on the forecasting accuracy. For that reason, this paper proposes a hybrid model based on data decomposition considering periodicity, trend and randomness of the original electrical load time series data. Through preprocessing and analyzing the original time series, the generalized regression neural network optimized by genetic algorithm is used to forecast the short-term electrical load. The experimental results demonstrate that the proposed hybrid model can not only achieve a good fitting ability, but it can also approximate the actual values when dealing with non-linear time series data with periodicity, trend and randomness.

  13. Advocating for School Psychologists in Response to the APA's Proposed "Model Act for State Licensure of Psychologists"

    Science.gov (United States)

    Skalski, Anastasia Kalamaros

    2009-01-01

    On March 6, 2009, the APA Model Licensure Act Task Force released its second draft of the policy document known as the proposed "Model Act for State Licensure of Psychologists". This policy document serves as guidance to state legislatures for how they should set up their psychology licensing laws. The general expectations promoted in the model…

  14. Upheaval Dome, Utah, USA: Impact Origin Confirmed

    OpenAIRE

    Buchner, Elmar; Kenkmann, Thomas

    2008-01-01

    Upheaval Dome is a unique circular structure on the Colorado Plateau in SE Utah, the origin of which has been controversially discussed for decades. It has been interpreted as a crypto volcanic feature, a salt diapir, a pinched-off salt diapir, and an eroded impact crater. While recent structural mapping, modeling, and analyses of deformation mechanisms strongly support an impact origin, ultimate proof, namely the documentation of unambiguous shock features, has yet to be successfully provide...

  15. Application of Artificial Bee Colony in Model Parameter Identification of Solar Cells

    Directory of Open Access Journals (Sweden)

    Rongjie Wang

    2015-07-01

    Full Text Available The identification of values of solar cell parameters is of great interest for evaluating solar cell performances. The algorithm of an artificial bee colony was used to extract model parameters of solar cells from current-voltage characteristics. Firstly, the best-so-for mechanism was introduced to the original artificial bee colony. Then, a method was proposed to identify parameters for a single diode model and double diode model using this improved artificial bee colony. Experimental results clearly demonstrate the effectiveness of the proposed method and its superior performance compared to other competing methods.

  16. Competency-Based University Undergraduate Teaching Management: Proposal for a Conceptual Model

    Directory of Open Access Journals (Sweden)

    Rodolfo Schmal

    2005-12-01

    Full Text Available The human resources societies and their organizations can count on are more and more relevant. In that sense, a major challenge faced by universities is to give students the appropriate background to be professionals with the profile the current scenario requires. This article focuses the management of university careers. Historically, many careers have emphasized knowledge, especially abstract knowledge. Today, the trend is to address aspects that reach beyond cognition, and focus the attention in effective competencies that include procedures and attitudes. Such approach allows the opportunity of defining a holistic management of careers, reaching beyond the sheer teaching of disciplines. Concurrently, the availability of information methods and tools will contribute for the definition and implementation of a design process that can work with explicit criteria and transformations. The article proposes a conceptual model to represent the objects, and their attributes and associations that are considered of interest for the management of university teaching under a competency focus. A second stage should implement such model through the construction of an information system that supports the management of corresponding careers.

  17. Modeling the Origin and Possible Control of the Wealth Inequality Surge.

    Science.gov (United States)

    Berman, Yonatan; Shapira, Yoash; Ben-Jacob, Eshel

    2015-01-01

    The rapid increase of wealth inequality in the past few decades is a most disturbing social and economic issue of our time. In order to control, and even reverse that surge, its origin and underlying mechanisms should be revealed. One of the challenges in studying these mechanisms is to incorporate realistic individual dynamics in the population level in a self-consistent manner. Our theoretical approach meets the challenge by using interacting multi-agent master-equations to model the dynamics of wealth inequality. The model is solved using stochastic multi-agent iterated maps. Taking into account growth rate, return on capital, private savings and economic mobility, we were able to capture the historical dynamics of wealth inequality in the United States during the course of the 20th century. We show that the fraction of capital income in the national income and the fraction of private savings are the critical factors that govern the wealth inequality dynamics. In addition, we found that economic mobility plays a crucial role in wealth accumulation. Notably, we found that the major decrease in private savings since the 1980s could be associated primarily with the recent surge in wealth inequality and if nothing changes in this respect we predict further increase in wealth inequality in the future. However, the 2007-08 financial crisis brought an opportunity to restrain the wealth inequality surge by increasing private savings. If this trend continues, it may lead to prevention, and even reversing, of the ongoing inequality surge.

  18. Revisit the Candidacy of Brain Cell Types as the Cell(s of Origin for Human High-Grade Glioma

    Directory of Open Access Journals (Sweden)

    Fangjie Shao

    2018-02-01

    Full Text Available High-grade glioma, particularly, glioblastoma, is the most aggressive cancer of the central nervous system (CNS in adults. Due to its heterogeneous nature, glioblastoma almost inevitably relapses after surgical resection and radio-/chemotherapy, and is thus highly lethal and associated with a dismal prognosis. Identifying the cell of origin has been considered an important aspect in understanding tumor heterogeneity, thereby holding great promise in designing novel therapeutic strategies for glioblastoma. Taking advantage of genetic lineage-tracing techniques, performed mainly on genetically engineered mouse models (GEMMs, multiple cell types in the CNS have been suggested as potential cells of origin for glioblastoma, among which adult neural stem cells (NSCs and oligodendrocyte precursor cells (OPCs are the major candidates. However, it remains highly debated whether these cell types are equally capable of transforming in patients, given that in the human brain, some cell types divide so slowly, therefore may never have a chance to transform. With the recent advances in studying adult NSCs and OPCs, particularly from the perspective of comparative biology, we now realize that notable differences exist among mammalian species. These differences have critical impacts on shaping our understanding of the cell of origin of glioma in humans. In this perspective, we update the current progress in this field and clarify some misconceptions with inputs from important findings about the biology of adult NSCs and OPCs. We propose to re-evaluate the cellular origin candidacy of these cells, with an emphasis on comparative studies between animal models and humans.

  19. A proposed adaptive step size perturbation and observation maximum power point tracking algorithm based on photovoltaic system modeling

    Science.gov (United States)

    Huang, Yu

    Solar energy becomes one of the major alternative renewable energy options for its huge abundance and accessibility. Due to the intermittent nature, the high demand of Maximum Power Point Tracking (MPPT) techniques exists when a Photovoltaic (PV) system is used to extract energy from the sunlight. This thesis proposed an advanced Perturbation and Observation (P&O) algorithm aiming for relatively practical circumstances. Firstly, a practical PV system model is studied with determining the series and shunt resistances which are neglected in some research. Moreover, in this proposed algorithm, the duty ratio of a boost DC-DC converter is the object of the perturbation deploying input impedance conversion to achieve working voltage adjustment. Based on the control strategy, the adaptive duty ratio step size P&O algorithm is proposed with major modifications made for sharp insolation change as well as low insolation scenarios. Matlab/Simulink simulation for PV model, boost converter control strategy and various MPPT process is conducted step by step. The proposed adaptive P&O algorithm is validated by the simulation results and detail analysis of sharp insolation changes, low insolation condition and continuous insolation variation.

  20. Common origin of visible and dark universe

    International Nuclear Information System (INIS)

    Gu Peihong; Sarkar, Utpal

    2010-01-01

    Dark matter, baryonic matter, and dark energy have different properties but contribute comparable energy density to the present Universe. We point out that they may have a common origin. As the dark energy has a scale far lower than all known scales in particle physics but very close to neutrino masses, while the excess matter over antimatter in the baryonic sector is probably related to the neutrino-mass generation, we unify the origin of the dark and visible universe in a variant of the seesaw model. In our model (i) the dark matter relic density is a dark matter asymmetry emerged simultaneously with the baryon asymmetry from leptogenesis; (ii) the dark energy is due to a pseudo-Nambu-Goldstone-Boson associated with the neutrino-mass generation.

  1. The Origin of Runaway Stars

    Science.gov (United States)

    Hoogerwerf, R.; de Bruijne, J. H. J.; de Zeeuw, P. T.

    2000-12-01

    Milliarcsecond astrometry provided by Hipparcos and by radio observations makes it possible to retrace the orbits of some of the nearest runaway stars and pulsars to determine their site of origin. The orbits of the runaways AE Aurigae and μ Columbae and of the eccentric binary ι Orionis intersected each other ~2.5 Myr ago in the nascent Trapezium cluster, confirming that these runaways were formed in a binary-binary encounter. The path of the runaway star ζ Ophiuchi intersected that of the nearby pulsar PSR J1932+1059, ~1 Myr ago, in the young stellar group Upper Scorpius. We propose that this neutron star is the remnant of a supernova that occurred in a binary system that also contained ζ Oph and deduce that the pulsar received a kick velocity of ~350 km s-1 in the explosion. These two cases provide the first specific kinematic evidence that both mechanisms proposed for the production of runaway stars, the dynamical ejection scenario and the binary-supernova scenario, operate in nature.

  2. A Proposed Model for Assessing Organisational Culture Towards Achieving Business Objectives

    Directory of Open Access Journals (Sweden)

    Hafez Salleh

    2011-09-01

    Full Text Available Most of the traditional business performances measures are based on productivity and process criteria, which mainly focus on method of investment appraisal such as payback method, return on investment (ROI, cost-benefits analysis (CBA, net present value (NPV, internal rate of return (IRR. However, the measurement scales of business performance are not limited to those measures. One element that has strong correlation to the business performances is ‘organisational culture’. Many studies proved that one of the significant criteria for achieving desired business objectives is the right organisational culture within workplace. Basically, the measurement of organisational culture is reflecting on two distinct elements: organisational culture and business objectives. In broader perspective, an organisation is considered effective if it meets its business objectives. This paper aims to present and discuss the preliminary culture model to indicate the culture performance within organisational. The model has been developed through literature review, expert opinion and experience which is anticipated of being able to potentially measure the culture capability of organisations across industries to “successfully achieve business objectives”. The model is composed of six progressive stages of maturity that an organisation can achieve its culture performance. For each maturity stage, the model describes a set of characteristics that must be in place for the company to achieve each stage. The validity of the proposed model will be tested by a few case studies. The idea is to provide managers with a qualitative measurement tools to enable them to identify where culture improvements are required within their organisations and to indicate their readiness for achieving business objectives.

  3. Robust watermarking on copyright protection of digital originals

    Energy Technology Data Exchange (ETDEWEB)

    Gu, C; Hu, X Y, E-mail: guchong527@gmail.co, E-mail: emma_huxy@yahoo.com.c [College of Packaging and Printing Engineering, Tianjin University of Science and Technology, Tianjin, 300222 (China)

    2010-06-01

    The issues about the difference between digital vector originals and raster originals were discussed. A new algorithm based on displacing vertices to realize the embedding and extracting of digital watermarking in vector data was proposed after that. The results showed that the watermark produced by the method is resistant against translation, scaling, rotation, additive random noise; it is also resistant, to some extent, against cropping. This paper also modified the DCT raster image watermarking algorithm, using a bitmap image as watermark embedded into target images, instead of some meaningless serial numbers or simple symbols. The embedding and extraction part of these two digital watermark systems achieved with software. Experiments proved that both algorithms are not only imperceptible, but also have strong resistance against the common attracts, which can prove the copyright more effectively.

  4. Modeling and energy efficiency optimization of belt conveyors

    International Nuclear Information System (INIS)

    Zhang, Shirong; Xia, Xiaohua

    2011-01-01

    Highlights: → We take optimization approach to improve operation efficiency of belt conveyors. → An analytical energy model, originating from ISO 5048, is proposed. → Then an off-line and an on-line parameter estimation schemes are investigated. → In a case study, six optimization problems are formulated with solutions in simulation. - Abstract: The improvement of the energy efficiency of belt conveyor systems can be achieved at equipment and operation levels. Specifically, variable speed control, an equipment level intervention, is recommended to improve operation efficiency of belt conveyors. However, the current implementations mostly focus on lower level control loops without operational considerations at the system level. This paper intends to take a model based optimization approach to improve the efficiency of belt conveyors at the operational level. An analytical energy model, originating from ISO 5048, is firstly proposed, which lumps all the parameters into four coefficients. Subsequently, both an off-line and an on-line parameter estimation schemes are applied to identify the new energy model, respectively. Simulation results are presented for the estimates of the four coefficients. Finally, optimization is done to achieve the best operation efficiency of belt conveyors under various constraints. Six optimization problems of a typical belt conveyor system are formulated, respectively, with solutions in simulation for a case study.

  5. The origin and evolution of phototropins

    Directory of Open Access Journals (Sweden)

    Fay-Wei eLi

    2015-08-01

    Full Text Available Plant phototropism, the ability to bend toward or away from light, is predominantly controlled by blue-light photoreceptors, the phototropins. Although phototropins have been well-characterized in Arabidopsis thaliana, their evolutionary history is largely unknown. In this study, we complete an in-depth survey of phototropin homologs across land plants and algae using newly available transcriptomic and genomic data. We show that phototropins originated in an ancestor of Viridiplantae (land plants + green algae. Phototropins repeatedly underwent independent duplications in most major land-plant lineages (mosses, lycophytes, ferns, and seed plants, but remained single-copy genes in liverworts and hornworts—an evolutionary pattern shared with another family of photoreceptors, the phytochromes. Following each major duplication event, the phototropins differentiated in parallel, resulting in two specialized, yet partially overlapping, functional forms that primarily mediate either low- or high-light responses. Our detailed phylogeny enables us to not only uncover new phototropin lineages, but also link our understanding of phototropin function in Arabidopsis with what is known in Adiantum and Physcomitrella (the major model organisms outside of flowering plants. We propose that the convergent functional divergences of phototropin paralogs likely contributed to the success of plants through time in adapting to habitats with diverse and heterogeneous light conditions.

  6. On the Origin of Heterotrophy.

    Science.gov (United States)

    Schönheit, Peter; Buckel, Wolfgang; Martin, William F

    2016-01-01

    The theory of autotrophic origins of life posits that the first cells on Earth satisfied their carbon needs from CO2. At hydrothermal vents, spontaneous synthesis of methane via serpentinization links an energy metabolic reaction with a geochemical homologue. If the first cells were autotrophs, how did the first heterotrophs arise, and what was their substrate? We propose that cell mass roughly similar to the composition of Escherichia coli was the substrate for the first chemoorganoheterotrophs. Amino acid fermentations, pathways typical of anaerobic clostridia and common among anaerobic archaea, in addition to clostridial type purine fermentations, might have been the first forms of heterotrophic carbon and energy metabolism. Ribose was probably the first abundant sugar, and the archaeal type III RubisCO pathway of nucleoside monophosphate conversion to 3-phosphoglycerate might be a relic of ancient heterotrophy. Participation of chemiosmotic coupling and flavin-based electron bifurcation--a soluble energy coupling process--in clostridial amino acid and purine fermentations is consistent with an autotrophic origin of both metabolism and heterotrophy, as is the involvement of S(0) as an electron acceptor in the facilitated fermentations of anaerobic heterotrophic archaea. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. A DYNAMICAL SYSTEM APPROACH IN MODELING TECHNOLOGY TRANSFER

    Directory of Open Access Journals (Sweden)

    Hennie Husniah

    2016-05-01

    Full Text Available In this paper we discuss a mathematical model of two parties technology transfer from a leader to a follower. The model is reconstructed via dynamical system approach from a known standard Raz and Assa model and we found some important conclusion which have not been discussed in the original model. The model assumes that in the absence of technology transfer from a leader to a follower, both the leader and the follower have a capability to grow independently with a known upper limit of the development. We obtain a rich mathematical structure of the steady state solution of the model. We discuss a special situation in which the upper limit of the technological development of the follower is higher than that of the leader, but the leader has started earlier than the follower in implementing the technology. In this case we show a paradox stating that the follower is unable to reach its original upper limit of the technological development could appear whenever the transfer rate is sufficiently high.  We propose a new model to increase realism so that any technological transfer rate could only has a positive effect in accelerating the rate of growth of the follower in reaching its original upper limit of the development.

  8. The “sanctity” of marriage – an archaeology of a socio-religious construct: Mythological origins, forms and models

    Directory of Open Access Journals (Sweden)

    Yolanda Dreyer

    2008-01-01

    Full Text Available The aim of the article is to argue that the sexual difference between female and male should be regarded as soteriologically indifferent. Though a biological reality of being human, sexuality is profoundly influenced by social constructs and the institution of marriage itself is a social construct. In this article the biological and social aspects are taken into account in a theological approach which on the one hand is interested in the relationship between God and human beings, and on the other in the way in which the Bible elucidates sexuality and marriage. The article indicates that the idea of sexual intercourse between a man and a woman as being equal to Godgiven “holy matrimony” has mythological origins. It focuses on these origins and on the multifarious forms of marital arrangements and models.

  9. Proposal of a congestion control technique in LAN networks using an econometric model ARIMA

    Directory of Open Access Journals (Sweden)

    Joaquín F Sánchez

    2017-01-01

    Full Text Available Hasty software development can produce immediate implementations with source code unnecessarily complex and hardly readable. These small kinds of software decay generate a technical debt that could be big enough to seriously affect future maintenance activities. This work presents an analysis technique for identifying architectural technical debt related to non-uniformity of naming patterns; the technique is based on term frequency over package hierarchies. The proposal has been evaluated on projects of two popular organizations, Apache and Eclipse. The results have shown that most of the projects have frequent occurrences of the proposed naming patterns, and using a graph model and aggregated data could enable the elaboration of simple queries for debt identification. The technique has features that favor its applicability on emergent architectures and agile software development.

  10. 75 FR 43590 - Self-Regulatory Organizations; Notice of Filing and Immediate Effectiveness of Proposed Rule...

    Science.gov (United States)

    2010-07-26

    ...), and sends a cancellation notice to the member that originally submitted the order. The instant.... Specifically, the Exchange believes that the proposal benefits customers by improving market efficiency through... the Commission, and all written communications relating to the proposed rule change between the...

  11. The modeling of contaminant flow during proposed treatment of U.S. Department of Energy low-level radioactive mixed wastes

    International Nuclear Information System (INIS)

    Dolak, D.A.; Wilkins, B.D.; Kotek, T.J.; Wang, Y.Y.; Meshkov, N.K.

    1995-01-01

    Estimations of waste materials throughput and the potential radiological and chemical releases resulting from the proposed treatment of US Department of Energy (DOE) low-level mixed wastes (LLMWs) were used to support analyses of risks and costs associated with various waste management alternatives outlined in the Office of Environmental Management Programmatic Environmental Impact Statement (EM PEIS). The modeling of material flow and contaminant releases through a consolidated waste management flowchart was performed by the WASTE MGMT computational model developed by Argonne National Laboratory. This paper (1) briefly describes the process used to model estimated material and contaminant flow through the proposed treatment scenarios for the EM PEIS, (2) discusses the key site- and/or waste-stream-dependent factors involved in the determination of radiological and chemical emissions, and (3) explains the assumptions used to integrate the available LLMW database with the computational model

  12. Origin of the pre-tropical storm Debby (2006) African easterly wave-mesoscale convective system

    Science.gov (United States)

    Lin, Yuh-Lang; Liu, Liping; Tang, Guoqing; Spinks, James; Jones, Wilson

    2013-05-01

    The origins of the pre-Debby (2006) mesoscale convective system (MCS) and African easterly wave (AEW) and their precursors were traced back to the southwest Arabian Peninsula, Asir Mountains (AS), and Ethiopian Highlands (EH) in the vicinity of the ITCZ using satellite imagery, GFS analysis data and ARW model. The sources of the convective cloud clusters and vorticity perturbations were attributed to the cyclonic convergence of northeasterly Shamal wind and the Somali jet, especially when the Mediterranean High shifted toward east and the Indian Ocean high strengthened and its associated Somali jet penetrated farther to the north. The cyclonic vorticity perturbations were strengthened by the vorticity stretching associated with convective cloud clusters in the genesis region—southwest Arabian Peninsula. A conceptual model was proposed to explain the genesis of convective cloud clusters and cyclonic vorticity perturbations preceding the pre-Debby (2006) AEW-MCS system.

  13. Origins of GEMS Grains

    Science.gov (United States)

    Messenger, S.; Walker, R. M.

    2012-01-01

    Interplanetary dust particles (IDPs) collected in the Earth s stratosphere contain high abundances of submicrometer amorphous silicates known as GEMS grains. From their birth as condensates in the outflows of oxygen-rich evolved stars, processing in interstellar space, and incorporation into disks around new stars, amorphous silicates predominate in most astrophysical environments. Amorphous silicates were a major building block of our Solar System and are prominent in infrared spectra of comets. Anhydrous interplanetary dust particles (IDPs) thought to derive from comets contain abundant amorphous silicates known as GEMS (glass with embedded metal and sulfides) grains. GEMS grains have been proposed to be isotopically and chemically homogenized interstellar amorphous silicate dust. We evaluated this hypothesis through coordinated chemical and isotopic analyses of GEMS grains in a suite of IDPs to constrain their origins. GEMS grains show order of magnitude variations in Mg, Fe, Ca, and S abundances. GEMS grains do not match the average element abundances inferred for ISM dust containing on average, too little Mg, Fe, and Ca, and too much S. GEMS grains have complementary compositions to the crystalline components in IDPs suggesting that they formed from the same reservoir. We did not observe any unequivocal microstructural or chemical evidence that GEMS grains experienced prolonged exposure to radiation. We identified four GEMS grains having O isotopic compositions that point to origins in red giant branch or asymptotic giant branch stars and supernovae. Based on their O isotopic compositions, we estimate that 1-6% of GEMS grains are surviving circumstellar grains. The remaining 94-99% of GEMS grains have O isotopic compositions that are indistinguishable from terrestrial materials and carbonaceous chondrites. These isotopically solar GEMS grains either formed in the Solar System or were completely homogenized in the interstellar medium (ISM). However, the

  14. Proposed shake table studies for NAPP containment

    International Nuclear Information System (INIS)

    Akolkar, P.M.; Khuddus, M.A.

    1975-01-01

    The proposal for shake table studies on model of containment structure of Narora Atomic Power Project is discussed. The physical characteristics such as the dimensions, connection details of the containment with the internal structure and the dynamic interaction between the two have been described. The dynamic scale factors obtained through similitude requirements and dimensional analysis have been presented and the modelling aspects and the choice of model material and scale have been discussed. The proposed type of tests, necessary measurement and instrumentation have been mentioned. The limitations imposed by similitude requirements on model studies are brought out and the usefulness of the results of the proposed tests in the dynamic design of the containment have been covered. (author)

  15. Tourism Cluster Competitiveness and Sustainability: Proposal for a Systemic Model to Measure the Impact of Tourism on Local Development

    Directory of Open Access Journals (Sweden)

    Sieglinde Kindl da Cunha

    2005-07-01

    Full Text Available This article proposes a model to measure tourism cluster impact on local development with a view to assessing tourism cluster interaction, competitiveness and sustainability impacts on the economy, society and the environment. The theoretical basis for this model is founded on cluster concept and typology adapting and integrating the systemic competitiveness and sustainability concepts within economic, social, cultural, environmental and political dimensions. The proposed model shows a holistic, multidisciplinary and multi-sector view of local development brought back through a systemic approach to the concepts of competitiveness, social equity and sustainability. Its results make possible strategic guidance to agents responsible for public sector tourism policies, as well as the strategies for competitiveness, competition, cooperation and sustainability in private companies and institutions.

  16. A novel approach to modeling atmospheric convection

    Science.gov (United States)

    Goodman, A.

    2016-12-01

    The inadequate representation of clouds continues to be a large source of uncertainty in the projections from global climate models (GCMs). With continuous advances in computational power, however, the ability for GCMs to explicitly resolve cumulus convection will soon be realized. For this purpose, Jung and Arakawa (2008) proposed the Vector Vorticity Model (VVM), in which vorticity is the predicted variable instead of momentum. This has the advantage of eliminating the pressure gradient force within the framework of an anelastic system. However, the VVM was designed for use on a planar quadrilateral grid, making it unsuitable for implementation in global models discretized on the sphere. Here we have proposed a modification to the VVM where instead the curl of the horizontal vorticity is the primary predicted variable. This allows us to maintain the benefits of the original VVM while working within the constraints of a non-quadrilateral mesh. We found that our proposed model produced results from a warm bubble simulation that were consistent with the VVM. Further improvements that can be made to the VVM are also discussed.

  17. Color-dielectric model as an explanation of the Nolen-Schiffer anomaly

    International Nuclear Information System (INIS)

    Williams, A.G.; Thomas, A.W.

    1986-01-01

    We discuss the quantum chromodynamically motivated color-dielectric model originally proposed by Nielsen and Patkos and show, using some straightforward approximations, that it can lead to charge-symmetry breaking effects in nuclei. We then show, using a local density approximation and standard nuclear structure properties, that for suitable choices of parameters this color-dielectric model can explain the Nolen-Schiffer anomaly

  18. Proposals for measuring transversity distributions in deep inelastic electron scattering and a model for E-704 asymmetries

    International Nuclear Information System (INIS)

    Artru, X.

    1993-10-01

    The principles of the measurement of the quark transversity distributions in semi-inclusive deep inelastic electron scattering are presented, which form the basis of Hydrogen jet target in the LEP tunnel (HELP) and one of the European Laboratory For Electron (ELFE) proposals. A string model for Collins-type asymmetry in polarized quark fragmentation function is proposed. A possible role of the Collins effect in the single spin asymmetries observed by experiment E 704 at Fermilab is suggested. (author) 13 refs., 3 figs

  19. Speculations on the origin and evolution of the Utopia-Elysium lowlands of Mars

    International Nuclear Information System (INIS)

    Frey, H.V.; Schultz, R.A.

    1990-01-01

    The origin of the overall low and variable topographic character of the northern plains is a fundamental aspect of the Martian crustal dichotomy. A model for the development of the Utopia-Elysium lowlands in eastern Mars in terms of the long-term evolution of large, overlapping impact basins is presented. The effects of relaxation of basin topography, volcanic flooding and loading of the basins with subsequent subsidence and downwarping, and the growth of a long-lived major tectonovolcanic center in the overlap region between the proposed Utopia and Elysium impact basins are qualitatively described. In an early hot, thin ( 22 P), relaxation of topographic relief was probably rapid ( 4 years) by comparison with the likely time between the two largest impacts (>10 6 years). The later Utopia Basin impact drastically altered the structure of the earlier Elysium Basin, uplifting portions of what had been the central depression. The heating and fracturing due to the impacts was most intense in the region of overlap, which probably provided an easy conduit for volcanic eruptions in this area. Loading by Early Hesperian and older basin volcanic caused widespread subsidence which may have extended beyond the basin rim and which was responsible for the generally low character of the northern plains, despite the minimum 2-3 km volcanic fill present there. Prolonged volcanism would likely keep the overlap region hotter longer, opposing later general subsidence of the impact basin floor where it had cooled. The authors suggest this model may be applicable to the origin of the northern lowlands elsewhere on Mars and that overlapping large impacts may be important in the establishment of the fundamental topographic and crustal dichtomy and the origin of major tectonovolcanic complexes on the planet

  20. Information dissemination model for social media with constant updates

    Science.gov (United States)

    Zhu, Hui; Wu, Heng; Cao, Jin; Fu, Gang; Li, Hui

    2018-07-01

    With the development of social media tools and the pervasiveness of smart terminals, social media has become a significant source of information for many individuals. However, false information can spread rapidly, which may result in negative social impacts and serious economic losses. Thus, reducing the unfavorable effects of false information has become an urgent challenge. In this paper, a new competitive model called DMCU is proposed to describe the dissemination of information with constant updates in social media. In the model, we focus on the competitive relationship between the original false information and updated information, and then propose the priority of related information. To more effectively evaluate the effectiveness of the proposed model, data sets containing actual social media activity are utilized in experiments. Simulation results demonstrate that the DMCU model can precisely describe the process of information dissemination with constant updates, and that it can be used to forecast information dissemination trends on social media.

  1. An Alternative Approach to the Extended Drude Model

    Science.gov (United States)

    Gantzler, N. J.; Dordevic, S. V.

    2018-05-01

    The original Drude model, proposed over a hundred years ago, is still used today for the analysis of optical properties of solids. Within this model, both the plasma frequency and quasiparticle scattering rate are constant, which makes the model rather inflexible. In order to circumvent this problem, the so-called extended Drude model was proposed, which allowed for the frequency dependence of both the quasiparticle scattering rate and the effective mass. In this work we will explore an alternative approach to the extended Drude model. Here, one also assumes that the quasiparticle scattering rate is frequency dependent; however, instead of the effective mass, the plasma frequency becomes frequency-dependent. This alternative model is applied to the high Tc superconductor Bi2Sr2CaCu2O8+δ (Bi2212) with Tc = 92 K, and the results are compared and contrasted with the ones obtained from the conventional extended Drude model. The results point to several advantages of this alternative approach to the extended Drude model.

  2. Proposed retention model for human inhalation exposure to 241AmO2

    International Nuclear Information System (INIS)

    Mewhinney, J.A.; Griffith, W.C.; Muggenburg, B.A.

    1980-01-01

    A dosimetry model based on a four-year study in Beagle dogs was developed to predict patterns of absorbed radiation doses for people exposed by inhalation to 241 AmO 2 . Following a single inhalation exposure to one of three sizes of monodisperse or a polydisperse aerosol of 241 AmO 2 , pairs of dogs were sacrificed at 8, 32, 64 and 256 days, and 2 and 4 years. For about 80% of the initial lung burden, the retention halftimes were 11, 18, 26 and 27 days for the 0.75, 1.5 and 3.0 μm aerodynamic diameter and the 1.8 μm activity median aerodynamic diameter aerosols, respectively. For the remaining 20% of the initial lung burden, the retention halftimes were between 200 to 300 days with no apparent particle size influence. Additional 241 Am metabolic studies reported in the literature using inhalation exposure or injection of the citrate complex were synthesized in the model as were eleven reported cases of human inhalation exposure. This model is compared to the ICRP II and TGLD lung models, both developed by analogy to Pu metabolism. The proposed model differs from these latter models in two important areas: (a) lung retention of 241 AmO 2 could not be adapted to the classifications used in these models, and (b) the fractional translocation from lung to other organs is 2 to 8 times larger. These factors considerably alter the predicted radiation dose distribution among organs and lead to the conclusion that derived radiation protection standards for 241 AmO 2 inhalation exposure should be modified. (author)

  3. Radiative neutrino mass model with degenerate right-handed neutrinos

    International Nuclear Information System (INIS)

    Kashiwase, Shoichi; Suematsu, Daijiro

    2016-01-01

    The radiative neutrino mass model can relate neutrino masses and dark matter at a TeV scale. If we apply this model to thermal leptogenesis, we need to consider resonant leptogenesis at that scale. It requires both finely degenerate masses for the right-handed neutrinos and a tiny neutrino Yukawa coupling. We propose an extension of the model with a U(1) gauge symmetry, in which these conditions are shown to be simultaneously realized through a TeV scale symmetry breaking. Moreover, this extension can bring about a small quartic scalar coupling between the Higgs doublet scalar and an inert doublet scalar which characterizes the radiative neutrino mass generation. It also is the origin of the Z 2 symmetry which guarantees the stability of dark matter. Several assumptions which are independently supposed in the original model are closely connected through this extension. (orig.)

  4. On the origin of mass in the standard model

    International Nuclear Information System (INIS)

    Sundman, S.

    2013-01-01

    A model is proposed in which the presently existing elementary particles are the result of an evolution proceeding from the simplest possible particle state to successively more complex states via a series of symmetry-breaking transitions. The properties of two fossil particles — the tauon and muon — together with the observed photon–baryon number ratio provide information that makes it possible to track the early development of particles. A computer simulation of the evolution reveals details about the purpose and history of all presently known elementary particles. In particular, it is concluded that the heavy Higgs particle that generates the bulk of the mass of the Z and W bosons also comes in a light version, which generates small mass contributions to the charged leptons. The predicted mass of this 'flyweight' Higgs boson is 0.505 MeV/c 2 , 106.086 eV/c 2 or 12.0007 μeV/c 2 (corresponding to a photon of frequency 2.9018 GHz) depending on whether it is associated with the tauon, muon or electron. Support for the conclusion comes from the Brookhaven muon g-2 experiment, which indicates the existence of a Higgs particle lighter than the muon. (author)

  5. Dynamic Model Averaging in Large Model Spaces Using Dynamic Occam's Window.

    Science.gov (United States)

    Onorante, Luca; Raftery, Adrian E

    2016-01-01

    Bayesian model averaging has become a widely used approach to accounting for uncertainty about the structural form of the model generating the data. When data arrive sequentially and the generating model can change over time, Dynamic Model Averaging (DMA) extends model averaging to deal with this situation. Often in macroeconomics, however, many candidate explanatory variables are available and the number of possible models becomes too large for DMA to be applied in its original form. We propose a new method for this situation which allows us to perform DMA without considering the whole model space, but using a subset of models and dynamically optimizing the choice of models at each point in time. This yields a dynamic form of Occam's window. We evaluate the method in the context of the problem of nowcasting GDP in the Euro area. We find that its forecasting performance compares well with that of other methods.

  6. Numerical assessment of the origin of deep salinity in a low permeability fractured medium

    International Nuclear Information System (INIS)

    Guimera, Jordi; Ruiz, Eduardo; Luna, Miguel; Arcos, David; Domenech, Cristina; Jordana, Salvador; Saegusa, Hiromitsu; Iwatsuki, Teruki

    2007-01-01

    Many possible origins have been proposed for the saline groundwater observed in many deep geological environments. In particular, samples obtained from deep boreholes located in granite at the Mizunami Underground Research Laboratory in Central Japan show total dissolved solids increasing to 50 mmol/L at depths below 800 m. Different hypothesis have been formulated to explain the observed fluid composition, among them, long-term water-rock interaction, mixing with residual fluids of magmatic origin and relict seawater dating from Miocene times. A review of the hydrochemical and isotopic data suggests that the three above hypotheses may be valid, at least to different degrees, or that processes acting over more recent geological times may be involved. The origin of the salinity was assessed by simulating land emersion by means of changing the upper recharge boundary. In this manner the Miocene seawater was modeled as being continually mixed with fresh water until the present time. The effects of different retardation processes were considered by varying factors such as matrix diffusion and fracture conductivity. Finally, geochemical reactions reproduced trends in major ions and master variables. This study shows that the salinity observed in the boreholes can be explained qualitatively as residual Miocene age seawater subjected to alteration due to long-term contact with the host material and continuous mixing with meteoric groundwater. (authors)

  7. Final Report: Model interacting particle systems for simulation and macroscopic description of particulate suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Peter J. Mucha

    2007-08-30

    Suspensions of solid particles in liquids appear in numerous applications, from environmental settings like river silt, to industrial systems of solids transport and water treatment, and biological flows such as blood flow. Despite their importance, much remains unexplained about these complicated systems. Mucha's research aims to improve understanding of basic properties of suspensions through a program of simulating model interacting particle systems with critical evaluation of proposed continuum equations, in close collaboration with experimentalists. Natural to this approach, the original proposal centered around collaboration with studies already conducted in various experimental groups. However, as was detailed in the 2004 progress report, following the first year of this award, a number of the questions from the original proposal were necessarily redirected towards other specific goals because of changes in the research programs of the proposed experimental collaborators. Nevertheless, the modified project goals and the results that followed from those goals maintain close alignment with the main themes of the original proposal, improving efficient simulation and macroscopic modeling of sedimenting and colloidal suspensions. In particular, the main investigations covered under this award have included: (1) Sedimentation instabilities, including the sedimentation analogue of the Rayleigh-Taylor instability (for heavy, particle-laden fluid over lighter, clear fluid). (2) Ageing dynamics of colloidal suspensions at concentrations above the glass transition, using simplified interactions. (3) Stochastic reconstruction of velocity-field dependence for particle image velocimetry (PIV). (4) Stochastic modeling of the near-wall bias in 'nano-PIV'. (5) Distributed Lagrange multiplier simulation of the 'internal splash' of a particle falling through a stable stratified interface. (6) Fundamental study of velocity fluctuations in sedimentation

  8. Impacts from Region-of-Origin Labeling on Consumer Product Perception and Purchasing Intention – Causal Relationships in a TPB based Model

    OpenAIRE

    Lorenz, Bettina A.; Hartmann, Monika; Simons, Johannes

    2014-01-01

    In this study, an extended TPB model is set up for purchasing behaviour of regional pork. It refers to research on organic food purchasing and on influences from region-of-origin labelling on product evaluation. Besides cognitive attitudes, subjective norms and perceived behavioural control, the model includes an element of personal norms and affective attitudes. Furthermore, identification with and perceived authenticity of a labelled region are considered. Empirical findings for 485 citizen...

  9. A synapse memristor model with forgetting effect

    International Nuclear Information System (INIS)

    Chen, Ling; Li, Chuandong; Huang, Tingwen; Chen, Yiran; Wen, Shiping; Qi, Jiangtao

    2013-01-01

    In this Letter we improved the ion diffusion term proposed in literature and redesigned the previous model as a dynamical model with two more internal state variables ‘forgetting rate’ and ‘retention’ besides the original variable ‘conductance’. The new model can not only describe the basic memory ability of memristor but also be able to capture the new finding forgetting behavior in memristor. And different from the previous model, the transition from short term memory to long term memory is also defined by the new model. Besides, the new model is better matched with the physical memristor (Pd/WOx/W) than the previous one.

  10. Case 3018. Cervus gouazoubira Fischer, 1814 (currently Mazama gouazoubira; Mammalia, Artiodactyla): proposed conservation as the correct original spelling

    Science.gov (United States)

    Gardner, A.L.

    1999-01-01

    The purpose of this application is to conserve the spelling of the specific name of Cervus gouazoubira Fischer, 1814 for the brown brocket deer of South America (family Cervidae). This spelling, rather than the original gouazoubira, has been in virtually universal usage for almost 50 years.

  11. Greedy Sampling and Incremental Surrogate Model-Based Tailoring of Aeroservoelastic Model Database for Flexible Aircraft

    Science.gov (United States)

    Wang, Yi; Pant, Kapil; Brenner, Martin J.; Ouellette, Jeffrey A.

    2018-01-01

    This paper presents a data analysis and modeling framework to tailor and develop linear parameter-varying (LPV) aeroservoelastic (ASE) model database for flexible aircrafts in broad 2D flight parameter space. The Kriging surrogate model is constructed using ASE models at a fraction of grid points within the original model database, and then the ASE model at any flight condition can be obtained simply through surrogate model interpolation. The greedy sampling algorithm is developed to select the next sample point that carries the worst relative error between the surrogate model prediction and the benchmark model in the frequency domain among all input-output channels. The process is iterated to incrementally improve surrogate model accuracy till a pre-determined tolerance or iteration budget is met. The methodology is applied to the ASE model database of a flexible aircraft currently being tested at NASA/AFRC for flutter suppression and gust load alleviation. Our studies indicate that the proposed method can reduce the number of models in the original database by 67%. Even so the ASE models obtained through Kriging interpolation match the model in the original database constructed directly from the physics-based tool with the worst relative error far below 1%. The interpolated ASE model exhibits continuously-varying gains along a set of prescribed flight conditions. More importantly, the selected grid points are distributed non-uniformly in the parameter space, a) capturing the distinctly different dynamic behavior and its dependence on flight parameters, and b) reiterating the need and utility for adaptive space sampling techniques for ASE model database compaction. The present framework is directly extendible to high-dimensional flight parameter space, and can be used to guide the ASE model development, model order reduction, robust control synthesis and novel vehicle design of flexible aircraft.

  12. ΛCDM model with dissipative nonextensive viscous dark matter

    Science.gov (United States)

    Gimenes, H. S.; Viswanathan, G. M.; Silva, R.

    2018-03-01

    Many models in cosmology typically assume the standard bulk viscosity. We study an alternative interpretation for the origin of the bulk viscosity. Using nonadditive statistics proposed by Tsallis, we propose a bulk viscosity component that can only exist by a nonextensive effect through the nonextensive/dissipative correspondence (NexDC). In this paper, we consider a ΛCDM model for a flat universe with a dissipative nonextensive viscous dark matter component, following the Eckart theory of bulk viscosity, without any perturbative approach. In order to analyze cosmological constraints, we use one of the most recent observations of Type Ia Supernova, baryon acoustic oscillations and cosmic microwave background data.

  13. Origin of the atmospheres of the earth and the planets

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Z M

    1978-06-01

    From a systematic analysis of the whole history of the protoplanetary cloud and the observational facts of the earth's atmosphere, new theory is proposed on the origin of the atmospheres of the earth and the planets. For the earth-like planets, there were profound primordial atmospheres originated from the protoplanetary cloud by the accretion of the embryoes of planets. These primordial atmospheres has existed in a time scale of 10/sup 3/ to 10/sup 7/ years and were composed of chemically reducing gases. The presence of such a reducing atmosphere may be of great significance to the theories of cosmogony and the origin of life. The contents are as follows: the escape of the nebulae and the planetary atmospheres, the blowing-off of the atmospheres and the disspiation of gases driven by the solar wind, the accretion of gases by the planetary embryoes, the primordial atmospheres.

  14. Origin of the Squantum 'Tillite', Massachusetts, USA: Modern Analogs and Implications for Neoproterozoic Climate Models

    Science.gov (United States)

    Carto, S. L.; Eyles, N.

    2009-05-01

    A central challenge to the 'Snowball Earth' hypothesis is whether the sedimentary rocks deposited during the Neoproterozoic (c. 750-570 Ma) are glacial tillites that accumulated under global ice sheets during this era. This uncertainty stems from the fact that diamictites are not uniquely glacial in origin, as the slumping and mixing of sediment downslope can also produce diamictites. A key deposit in this debate is the Squantum 'tillite' (ca. 595-570 Ma) preserved in the Boston Basin in Massachusetts, USA, which originated as an arc- related basin within the Avalon island arc terrane during the Neoproterozoic. Detailed field examinations of the Squantum by the author suggest that it owes its origin to the downslope transport of large volumes of unstable volcanic and sedimentary debris from steep basin margin slopes. No evidence of a glacial environment was identified. Thin-section analysis of this deposit has revealed a significant volcanic influence on sedimentation in the form of hitherto unrecognized volcanic lapilli tuff horizons and turbidites consisting of reworked ash in strata associated with Squantum diamictite. These results point to deposition related to tectonic activity and basin development rather than severe global glacial conditions. In light of these results, the Squantum diamictite was compared to the volcaniclastic mass flows deposits exposed along the active Lesser Antilles Arc in the Caribbean. Many of these flows are transported into the adjacent Grenada back-arc Basin by debris flows and turbidity currents resulting in the deposition of volcaniclastic conglomerates, diamictites and thin ash turbidites. Gross stratigraphic and sedimentological similarities of the mass flow facies in the Caribbean can be identified with the Squantum deposits, suggesting that appropriate depositional analogs for the Squantum can be found along the Lesser Antilles Arc. The significance of these results is that they emphasize the importance of detailed field

  15. Proposal of a stationary model of dispersion diagnoses of pollutants chemically non-reactivate, applied for mobile sources in Bogota

    International Nuclear Information System (INIS)

    Ruiz Murcia, Jose Franklln; Pabon Caicedo, Jose Daniel

    2002-01-01

    The following document presents a semi empirical model to calculate concentrations of monoxide of carbon in surface by mobile sources. This model considers three basic components: meteorology, emissions and atmospheric chemistry. Scientifically, the propose model is sustained en the fact that the quality of the air depends of the weather's conditions and the numbers of source that is emitting

  16. Thermo-mechanical constitutive modeling of unsaturated clays based on the critical state concepts

    OpenAIRE

    Tourchi, Saeed; Hamidi, Amir

    2015-01-01

    A thermo-mechanical constitutive model for unsaturated clays is constructed based on the existing model for saturated clays originally proposed by the authors. The saturated clays model was formulated in the framework of critical state soil mechanics and modified Cam-clay model. The existing model has been generalized to simulate the experimentally observed behavior of unsaturated clays by introducing Bishop's stress and suction as independent stress parameters and modifying the hardening rul...

  17. Feature selection and recognition from nonspecific volatile profiles for discrimination of apple juices according to variety and geographical origin.

    Science.gov (United States)

    Guo, Jing; Yue, Tianli; Yuan, Yahong

    2012-10-01

    Apple juice is a complex mixture of volatile and nonvolatile components. To develop discrimination models on the basis of the volatile composition for an efficient classification of apple juices according to apple variety and geographical origin, chromatography volatile profiles of 50 apple juice samples belonging to 6 varieties and from 5 counties of Shaanxi (China) were obtained by headspace solid-phase microextraction coupled with gas chromatography. The volatile profiles were processed as continuous and nonspecific signals through multivariate analysis techniques. Different preprocessing methods were applied to raw chromatographic data. The blind chemometric analysis of the preprocessed chromatographic profiles was carried out. Stepwise linear discriminant analysis (SLDA) revealed satisfactory discriminations of apple juices according to variety and geographical origin, provided respectively 100% and 89.8% success rate in terms of prediction ability. Finally, the discriminant volatile compounds selected by SLDA were identified by gas chromatography-mass spectrometry. The proposed strategy was able to verify the variety and geographical origin of apple juices involving only a reduced number of discriminate retention times selected by the stepwise procedure. This result encourages the similar procedures to be considered in quality control of apple juices. This work presented a method for an efficient discrimination of apple juices according to apple variety and geographical origin using HS-SPME-GC-MS together with chemometric tools. Discrimination models developed could help to achieve greater control over the quality of the juice and to detect possible adulteration of the product. © 2012 Institute of Food Technologists®

  18. Modeling of Multisize Bubbly Flow and Application to the Simulation of Boiling Flows with the Neptune_CFD Code

    Directory of Open Access Journals (Sweden)

    Christophe Morel

    2009-01-01

    Full Text Available This paper describes the modeling of boiling multisize bubbly flows and its application to the simulation of the DEBORA experiment. We follow the method proposed originally by Kamp, assuming a given mathematical expression for the bubble diameter pdf. The original model is completed by the addition of some new terms for vapor compressibility and phase change. The liquid-to-interface heat transfer term, which essentially determines the bubbles condensation rate in the DEBORA experiment, is also modeled with care. First numerical results realized with the Neptune_CFD code are presented and discussed.

  19. Origin of the solar system s-process abundances

    International Nuclear Information System (INIS)

    Malaney, R.A.; Boothroyd, A.I.

    1987-01-01

    In the search for the origin of the solar system s-process abundances much attention has been focused on the intershell zones of thermally pulsing asymptotic giant branch (AGB) stars. It has recently been suggested that, relative to the poor fits obtained from intermediate-mass AGB models, low-mass AGB models may result in much better fits to the observed solar system abundances. This suggestion was motivated by the high intershell base temperatures indicated by recent low-mass AGB calculations. Using new data, presented for the peak intershell base temperature in such stars, the s-process enhancements occurring in the intershell zones of low-mass AGB stars are calculated. A nonsolar distribution of s-process abundances is reported for all realistic AGB models studied. Other possible astrophysical sites for the origin of the solar system s-process abundances are discussed. 35 references

  20. Air Emissions Damages from Municipal Drinking Water Treatment Under Current and Proposed Regulatory Standards.

    Science.gov (United States)

    Gingerich, Daniel B; Mauter, Meagan S

    2017-09-19

    Water treatment processes present intersectoral and cross-media risk trade-offs that are not presently considered in Safe Drinking Water Act regulatory analyses. This paper develops a method for assessing the air emission implications of common municipal water treatment processes used to comply with recently promulgated and proposed regulatory standards, including concentration limits for, lead and copper, disinfection byproducts, chromium(VI), strontium, and PFOA/PFOS. Life-cycle models of electricity and chemical consumption for individual drinking water unit processes are used to estimate embedded NO x , SO 2 , PM 2.5 , and CO 2 emissions on a cubic meter basis. We estimate air emission damages from currently installed treatment processes at U.S. drinking water facilities to be on the order of $500 million USD annually. Fully complying with six promulgated and proposed rules would increase baseline air emission damages by approximately 50%, with three-quarters of these damages originating from chemical manufacturing. Despite the magnitude of these air emission damages, the net benefit of currently implemented rules remains positive. For some proposed rules, however, the promise of net benefits remains contingent on technology choice.

  1. Contact angle adjustment in equation-of-state-based pseudopotential model.

    Science.gov (United States)

    Hu, Anjie; Li, Longjian; Uddin, Rizwan; Liu, Dong

    2016-05-01

    The single component pseudopotential lattice Boltzmann model has been widely applied in multiphase simulation due to its simplicity and stability. In many studies, it has been claimed that this model can be stable for density ratios larger than 1000. However, the application of the model is still limited to small density ratios when the contact angle is considered. The reason is that the original contact angle adjustment method influences the stability of the model. Moreover, simulation results in the present work show that, by applying the original contact angle adjustment method, the density distribution near the wall is artificially changed, and the contact angle is dependent on the surface tension. Hence, it is very inconvenient to apply this method with a fixed contact angle, and the accuracy of the model cannot be guaranteed. To solve these problems, a contact angle adjustment method based on the geometry analysis is proposed and numerically compared with the original method. Simulation results show that, with our contact angle adjustment method, the stability of the model is highly improved when the density ratio is relatively large, and it is independent of the surface tension.

  2. Original geochemical types and epigenetic alteration of rocks in prospecting target stratum for uranium deposit in the southeast of Songliao basin

    International Nuclear Information System (INIS)

    Lin Jinrong; Tian Hua; Dong Wenming; Xia Yuliang; Qi Daneng; Yao Shancong; Zheng Jiwei

    2009-01-01

    By comprehensive analysis on informations of regional geology and evaluating drillhole works of uranium resources in the southeast of Songliao basin, lithofacies-palaeogeography features, lithologies and sandbody characteristics of target layes in Quantou formation, Yaojia formation and Sifangtai formation have been basically found out. By research on geochemical environment of rocks in target layez, types of original geochemistry and epigenetic alteration have been identified and classified. The types of original geochemistry have been divided into types of original oxidation and original reduction, and the types of epigenetic alteration have been divided into types of reduction by oil-gas and coalbed gas and epigenetic oxidation. By comparative study on mineral and chemical characteristics of original geochemistry and epigenetic oxidation, identification marks for oil-gas and coalbed gas reduced epigenetic oxidation have been proposed. It is proposed that uranium was strongly pre-concentrated in original sandstone that bearing carboniferous matter, and reduction by oil-gas and coalbed gas made uranium superimpose and concentrate in alterated rocks. (authors)

  3. Socio-economic vulnerability to natural hazards - proposal for an indicator-based model

    Science.gov (United States)

    Eidsvig, U.; McLean, A.; Vangelsten, B. V.; Kalsnes, B.; Ciurean, R. L.; Argyroudis, S.; Winter, M.; Corominas, J.; Mavrouli, O. C.; Fotopoulou, S.; Pitilakis, K.; Baills, A.; Malet, J. P.

    2012-04-01

    Vulnerability assessment, with respect to natural hazards, is a complex process that must consider multiple dimensions of vulnerability, including both physical and social factors. Physical vulnerability refers to conditions of physical assets, and may be modeled by the intensity and magnitude of the hazard, the degree of physical protection provided by the natural and built environment, and the physical robustness of the exposed elements. Social vulnerability refers to the underlying factors leading to the inability of people, organizations, and societies to withstand impacts from the natural hazards. Social vulnerability models can be used in combination with physical vulnerability models to estimate both direct losses, i.e. losses that occur during and immediately after the impact, as well as indirect losses, i.e. long-term effects of the event. Direct impact of a landslide typically includes casualties and damages to buildings and infrastructure while indirect losses may e.g. include business closures or limitations in public services. The direct losses are often assessed using physical vulnerability indicators (e.g. construction material, height of buildings), while indirect losses are mainly assessed using social indicators (e.g. economical resources, demographic conditions). Within the EC-FP7 SafeLand research project, an indicator-based method was proposed to assess relative socio-economic vulnerability to landslides. The indicators represent the underlying factors which influence a community's ability to prepare for, deal with, and recover from the damage associated with landslides. The proposed model includes indicators representing demographic, economic and social characteristics as well as indicators representing the degree of preparedness and recovery capacity. Although the model focuses primarily on the indirect losses, it could easily be extended to include more physical indicators which account for the direct losses. Each indicator is individually

  4. Islet Cells Serve as Cells of Origin of Pancreatic Gastrin-Positive Endocrine Tumors.

    Science.gov (United States)

    Bonnavion, Rémy; Teinturier, Romain; Jaafar, Rami; Ripoche, Doriane; Leteurtre, Emmanuelle; Chen, Yuan-Jia; Rehfeld, Jens F; Lepinasse, Florian; Hervieu, Valérie; Pattou, François; Vantyghem, Marie-Christine; Scoazec, Jean-Yves; Bertolino, Philippe; Zhang, Chang Xian

    2015-10-01

    The cells of origin of pancreatic gastrinomas remain an enigma, since no gastrin-expressing cells are found in the normal adult pancreas. It was proposed that the cellular origin of pancreatic gastrinomas may come from either the pancreatic cells themselves or gastrin-expressing cells which have migrated from the duodenum. In the current study, we further characterized previously described transient pancreatic gastrin-expressing cells using cell lineage tracing in a pan-pancreatic progenitor and a pancreatic endocrine progenitor model. We provide evidence showing that pancreatic gastrin-expressing cells, found from embryonic day 12.5 until postnatal day 7, are derived from pancreatic Ptf1a(+) and neurogenin 3-expressing (Ngn3(+)) progenitors. Importantly, the majority of them coexpress glucagon, with 4% coexpressing insulin, indicating that they are a temporary subpopulation of both alpha and beta cells. Interestingly, Men1 disruption in both Ngn3 progenitors and beta and alpha cells resulted in the development of pancreatic gastrin-expressing tumors, suggesting that the latter developed from islet cells. Finally, we detected gastrin expression using three human cohorts with pancreatic endocrine tumors (pNETs) that have not been diagnosed as gastrinomas (in 9/34 pNETs from 6/14 patients with multiple endocrine neoplasia type 1, in 5/35 sporadic nonfunctioning pNETs, and in 2/20 sporadic insulinomas), consistent with observations made in mouse models. Our work provides insight into the histogenesis of pancreatic gastrin-expressing tumors. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  5. The k-ε-fP model applied to double wind turbine wakes using different actuator disk force methods

    DEFF Research Database (Denmark)

    Laan, van der, Paul Maarten; Sørensen, Niels N.; Réthoré, Pierre-Elouan

    2015-01-01

    The newly developed k-ε-fP  eddy viscosity model is applied to double wind turbine wake configurations in a neutral atmospheric boundary layer, using a Reynolds-Averaged Navier–Stokes solver. The wind turbines are represented by actuator disks. A proposed variable actuator disk force method...... two methods overpredict it. The results of the k-ε-fP  eddy viscosity model are also compared with the original k-ε eddy viscosity model and large-eddy simulations. Compared to the large-eddy simulations-predicted velocity and power deficits, the k-ε-fP  is superior to the original k-ε model...

  6. The Romeu pluton, NE Portugal: constraints on the origin of leucogranite

    International Nuclear Information System (INIS)

    Wallfass, C.M.

    1987-01-01

    This the petrogenesis of the Romeu leucogranites can be satisfactorily explained by a fractionation model in which an original granite magma produced a leucogranites rest melt. The S-type characteristics of the leucogranites (high paraluminicity, high initial Sr isotope ratio and the pattern of trace element enrichment and depletion) follow from this model. Research within the Ibergranite Project show that the granite magmas derive from earlier mets, wich descendent from gabbro melts, ultimately originating in the matle. It is possible that the original magma was contaminated with crustal rocks during its residence in the lower crust, but these leucogranites are uncontaminated high level fractionates. (C.D.G.) [pt

  7. Modeling decoherence with qubits

    Science.gov (United States)

    Heusler, Stefan; Dür, Wolfgang

    2018-03-01

    Quantum effects like the superposition principle contradict our experience of daily life. Decoherence can be viewed as a possible explanation why we do not observe quantum superposition states in the macroscopic world. In this article, we use the qubit ansatz to discuss decoherence in the simplest possible model system and propose a visualization for the microscopic origin of decoherence, and the emergence of a so-called pointer basis. Finally, we discuss the possibility of ‘macroscopic’ quantum effects.

  8. The Origin of Solar Filament Plasma Inferred from In Situ Observations of Elemental Abundances

    Energy Technology Data Exchange (ETDEWEB)

    Song, H. Q.; Chen, Y.; Li, B. [Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, and Institute of Space Sciences, Shandong University, Weihai, Shandong 264209 (China); Li, L. P. [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Zhao, L. [Department of Climate and Space sciences and Engineering, University of Michigan, Ann Arbor, MI 48105 (United States); He, J. S.; Duan, D. [School of Earth and Space Sciences, Peking University, Beijing 100871 (China); Cheng, X. [School of Astronomy and Space Science, Nanjing University, Nanjing, Jiangsu 210093 (China); Zhang, J., E-mail: hqsong@sdu.edu.cn [Department of Physics and Astronomy, George Mason University, Fairfax, VA 22030 (United States)

    2017-02-10

    Solar filaments/prominences are one of the most common features in the corona, which may lead to energetic coronal mass ejections (CMEs) and flares when they erupt. Filaments are about 100 times cooler and denser than the coronal material, and physical understanding of their material origin remains controversial. Two types of scenarios have been proposed: one argues that the filament plasma is brought into the corona from photosphere or chromosphere through a siphon or evaporation/injection process, while the other suggests that the material condenses from the surrounding coronal plasma due to thermal instability. The elemental abundance analysis is a reasonable clue to constrain the models, as the siphon or evaporation/injection model would predict that the filament material abundances are close to the photospheric or chromospheric ones, while the condensation model should have coronal abundances. In this Letter, we analyze the elemental abundances of a magnetic cloud that contains the ejected filament material. The corresponding filament eruption occurred on 1998 April 29, accompanying an M6.8 class soft X-ray flare located at the heliographic coordinates S18E20 (NOAA 08210) and a fast halo CME with the linear velocity of 1374 km s{sup −1} near the Sun. We find that the abundance ratios of elements with low and high first ionization potential such as Fe/O, Mg/O, and Si/O are 0.150, 0.050, and 0.070, respectively, approaching their corresponding photospheric values 0.065, 0.081, and 0.066, which does not support the coronal origin of the filament plasma.

  9. Proposing a Model to present Factors which Affect e-SCM Risk and their Impacts on Organizational Performance

    Directory of Open Access Journals (Sweden)

    ali rajabzadeh ghatari

    2010-03-01

    Full Text Available Companies strive to improve market share, grow corporate profit, and gain strategic advantage. In order to achieve these goals, supply chain competency must be placed at the heart of a company’s business model. Using e-Commerce and information and communication technologies (ICT in today’s changing demands of business has made organizations more responsive and flexible. E-Commerce and Internet have changed the nature of supply chains and re-defined how customers obtain wisdom of products, services, selection, purchasing and using them. Advent of ICT and new business environment has caused emerge of electronic supply chains. This research has proposed a model for presenting factors which affect electronic supply chain’s risk; besides the influence of the risk on financial and non-financial organization’s performance indicators. Studying the influence of the risk on organization’s performance is conducted in a sample of electronic and telecommunication companies. In order to measure these relationships, using correlation and structural equation modeling (SEM techniques proposed that electronic supply chain risk identification and management have significant impact on organization’s performance improvement.

  10. Out of Africa: modern human origins special feature: the origin of Neandertals.

    Science.gov (United States)

    Hublin, J J

    2009-09-22

    Western Eurasia yielded a rich Middle (MP) and Late Pleistocene (LP) fossil record documenting the evolution of the Neandertals that can be analyzed in light of recently acquired paleogenetical data, an abundance of archeological evidence, and a well-known environmental context. Their origin likely relates to an episode of recolonization of Western Eurasia by hominins of African origin carrying the Acheulean technology into Europe around 600 ka. An enhancement of both glacial and interglacial phases may have played a crucial role in this event, as well as in the subsequent evolutionary history of the Western Eurasian populations. In addition to climatic adaptations and an increase in encephalization, genetic drift seems to have played a major role in their evolution. To date, a clear speciation event is not documented, and the most likely scenario for the fixation of Neandertal characteristics seems to be an accretion of features along the second half of the MP. Although a separation time for the African and Eurasian populations is difficult to determine, it certainly predates OIS 11 as phenotypic Neandertal features are documented as far back as and possibly before this time. It is proposed to use the term "Homo rhodesiensis" to designate the large-brained hominins ancestral to H. sapiens in Africa and at the root of the Neandertals in Europe, and to use the term "Homo neanderthalensis" to designate all of the specimens carrying derived metrical or non-metrical features used in the definition of the LP Neandertals.

  11. Local hidden variable modelling, classicality, quantum separability and the original Bell inequality

    International Nuclear Information System (INIS)

    Loubenets, Elena R

    2011-01-01

    We introduce a general condition sufficient for the validity of the original Bell inequality (1964) in a local hidden variable (LHV) frame. This condition can be checked experimentally and incorporates only as a particular case the assumption on perfect correlations or anticorrelations usually argued for this inequality in the literature. Specifying this general condition for a quantum bipartite case, we introduce the whole class of bipartite quantum states, separable and nonseparable, that (i) admit an LHV description under any bipartite measurements with two settings per site; (ii) do not necessarily exhibit perfect correlations and may even have a negative correlation function if the same quantum observable is measured at both sites, but (iii) satisfy the 'perfect correlation' version of the original Bell inequality for any three bounded quantum observables A 1 , A 2 = B 1 , B 2 at sites 'A' and 'B', respectively. Analysing the validity of this general LHV condition under classical and quantum correlation scenarios with the same physical context, we stress that, unlike the Clauser-Horne-Shimony-Holt inequality, the original Bell inequality distinguishes between classicality and quantum separability.

  12. Origin of intragranular crystallographic misorientations in hot-dip Al-Zn-Si coatings

    International Nuclear Information System (INIS)

    Niederberger, Ch.; Michler, J.; Jacot, A.

    2008-01-01

    The origin of intragranular variations of the crystallographic orientation in hot-dip Al-Zn-Si coatings is discussed based on new experimental results and modelling. The solidification microstructure in as-received 55Al-43.4Zn-1.6Si (in wt.%) coatings deposited on steel plates in an industrial production line was analyzed by electron backscattered diffraction, glow-discharge optical emission spectroscopy and atomic force microscopy (AFM). The results were compared with those obtained in coatings re-solidified under different cooling and mechanical loading conditions. Continuous variations of the crystallographic orientation as large as 35 deg. were observed within individual grains of Al-Zn-Si, consistent with previous studies. However, the mechanisms previously proposed for the origin of intragranular crystallographic misorientations had to be revisited. The new experimental data acquired during this study indicate that the solidification shrinkage accumulating in the area of the grain envelope is the driving force for the formation of intragranular misorientations. The solidification shrinkage leads to the development of tensile stresses in the oxide film covering the coating while it solidifies. Estimations based on AFM profiles and phase field simulations of the dendritic structure indicate that the stresses applied on the dendrite network are sufficient to deform plastically the dendrite arms during solidification

  13. Bethe ansatz study for ground state of Fateev Zamolodchikov model

    International Nuclear Information System (INIS)

    Ray, S.

    1997-01-01

    A Bethe ansatz study of a self-dual Z N spin lattice model, originally proposed by V. A. Fateev and A. B. Zamolodchikov, is undertaken. The connection of this model to the Chiral Potts model is established. Transcendental equations connecting the zeros of Fateev endash Zamolodchikov transfer matrix are derived. The free energies for the ferromagnetic and the anti-ferromagnetic ground states are found for both even and odd spins. copyright 1997 American Institute of Physics

  14. The Origin of Mathematics and Number Sense in the Cerebellum: with Implications for Finger Counting and Dyscalculia.

    Science.gov (United States)

    Vandervert, Larry

    2017-01-01

    Mathematicians and scientists have struggled to adequately describe the ultimate foundations of mathematics. Nobel laureates Albert Einstein and Eugene Wigner were perplexed by this issue, with Wigner concluding that the workability of mathematics in the real world is a mystery we cannot explain. In response to this classic enigma, the major purpose of this article is to provide a theoretical model of the ultimate origin of mathematics and "number sense" (as defined by S. Dehaene) that is proposed to involve the learning of inverse dynamics models through the collaboration of the cerebellum and the cerebral cortex (but prominently cerebellum-driven). This model is based upon (1) the modern definition of mathematics as the "science of patterns," (2) cerebellar sequence (pattern) detection, and (3) findings that the manipulation of numbers is automated in the cerebellum. This cerebro-cerebellar approach does not necessarily conflict with mathematics or number sense models that focus on brain functions associated with especially the intraparietal sulcus region of the cerebral cortex. A direct corollary purpose of this article is to offer a cerebellar inner speech explanation for difficulty in developing "number sense" in developmental dyscalculia. It is argued that during infancy the cerebellum learns (1) a first tier of internal models for a primitive physics that constitutes the foundations of visual-spatial working memory, and (2) a second (and more abstract) tier of internal models based on (1) that learns "number" and relationships among dimensions across the primitive physics of the first tier. Within this context it is further argued that difficulty in the early development of the second tier of abstraction (and "number sense") is based on the more demanding attentional requirements imposed on cerebellar inner speech executive control during the learning of cerebellar inverse dynamics models. Finally, it is argued that finger counting improves (does not

  15. Exploring the Origins of Deuterium Enrichments in Solar Nebular Organics

    Science.gov (United States)

    Cleeves, L. Ilsedore; Bergin, Edwin A.; O'D. Alexander, Conel M.; Du, Fujun; Graninger, Dawn; Öberg, Karin I.; Harries, Tim J.

    2016-03-01

    Deuterium-to-hydrogen (D/H) enrichments in molecular species provide clues about their original formation environment. The organic materials in primitive solar system bodies generally have higher D/H ratios and show greater D/H variation when compared to D/H in solar system water. We propose this difference arises at least in part due to (1) the availability of additional chemical fractionation pathways for organics beyond that for water, and (2) the higher volatility of key carbon reservoirs compared to oxygen. We test this hypothesis using detailed disk models, including a sophisticated, new disk ionization treatment with a low cosmic-ray ionization rate, and find that disk chemistry leads to higher deuterium enrichment in organics compared to water, helped especially by fractionation via the precursors CH2D+/CH3+. We also find that the D/H ratio in individual species varies significantly depending on their particular formation pathways. For example, from ˜20-40 au, CH4 can reach {{D}}/{{H}}˜ 2× {10}-3, while D/H in CH3OH remains locally unaltered. Finally, while the global organic D/H in our models can reproduce intermediately elevated D/H in the bulk hydrocarbon reservoir, our models are unable to reproduce the most deuterium-enriched organic materials in the solar system, and thus our model requires some inheritance from the cold interstellar medium from which the Sun formed.

  16. Cyclic Concatenated Genetic Encoder: A mathematical proposal for biological inferences.

    Science.gov (United States)

    Duarte-González, M E; Echeverri, O Y; Guevara, J M; Palazzo, R

    2018-01-01

    The organization of the genetic information and its ability to be conserved and translated to proteins with low error rates have been the subject of study by scientists from different disciplines. Recently, it has been proposed that living organisms display an intra-cellular transmission system of genetic information, similar to a model of digital communication system, in which there is the ability to detect and correct errors. In this work, the concept of Concatenated Genetic Encoder is introduced and applied to the analysis of protein sequences as a tool for exploring evolutionary relationships. For such purposes Error Correcting Codes (ECCs) are used to represent proteins. A methodology for representing or identifying proteins by use of BCH codes over ℤ 20 and F 4 ×ℤ 5 is proposed and cytochrome b6-f complex subunit 6-OS sequences, corresponding to different plants species, are analyzed according to the proposed methodology and results are contrasted to phylogenetic and taxonomic analyses. Through the analyses, it was observed that using BCH codes only some sequences are identified, all of which differ in one amino acid from the original sequence. In addition, mathematical relationships among identified sequences are established by considering minimal polynomials, where such sequences showed a close relationship as revealed in the phylogenetic reconstruction. Results, here shown, point out that communication theory may provide biology of interesting and useful tools to identify biological relationships among proteins, however the proposed methodology needs to be improved and rigorously tested in order to become into an applicable tool for biological analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Original analytical model of the hydrodynamic loads applied on the half-bridge of a circular settling tank

    Science.gov (United States)

    Oanta, Emil M.; Dascalescu, Anca-Elena; Sabau, Adrian

    2016-12-01

    The paper presents an original analytical model of the hydrodynamic loads applied on the half-bridge of a circular settling tank. The calculus domain is defined using analytical geometry and the calculus of the local dynamic pressure is based on the radius from the center of the settling tank to the current area, i.e. the relative velocity of the fluid and the depth where the current area is located, i.e. the density of the fluid. Calculus of the local drag forces uses the discrete frontal cross sectional areas of the submerged structure in contact with the fluid. In the last stage is performed the reduction of the local drag forces in the appropriate points belonging to the main beam. This class of loads is producing the flexure of the main beam in a horizontal plane and additional twisting moments along this structure. Taking into account the hydrodynamic loads, the results of the theoretical models, i.e. the analytical model and the finite element model, may have an increased accuracy.

  18. Integrating model checking with HiP-HOPS in model-based safety analysis

    International Nuclear Information System (INIS)

    Sharvia, Septavera; Papadopoulos, Yiannis

    2015-01-01

    The ability to perform an effective and robust safety analysis on the design of modern safety–critical systems is crucial. Model-based safety analysis (MBSA) has been introduced in recent years to support the assessment of complex system design by focusing on the system model as the central artefact, and by automating the synthesis and analysis of failure-extended models. Model checking and failure logic synthesis and analysis (FLSA) are two prominent MBSA paradigms. Extensive research has placed emphasis on the development of these techniques, but discussion on their integration remains limited. In this paper, we propose a technique in which model checking and Hierarchically Performed Hazard Origin and Propagation Studies (HiP-HOPS) – an advanced FLSA technique – can be applied synergistically with benefit for the MBSA process. The application of the technique is illustrated through an example of a brake-by-wire system. - Highlights: • We propose technique to integrate HiP-HOPS and model checking. • State machines can be systematically constructed from HiP-HOPS. • The strengths of different MBSA techniques are combined. • Demonstrated through modeling and analysis of brake-by-wire system. • Root cause analysis is automated and system dynamic behaviors analyzed and verified

  19. Modeling oscillatory dynamics in brain microcircuits as a way to help uncover neurological disease mechanisms: A proposal

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, F. K. [Toronto Western Research Institute, University Health Network, Krembil Discovery Tower, Toronto Western Hospital, 60 Leonard Street, 7th floor, 7KD411, Toronto, Ontario M5T 2S8 (Canada); Department of Medicine (Neurology), University of Toronto, 200 Elizabeth Street, Toronto, Ontario M5G 2C4 (Canada); Department of Physiology, University of Toronto Medical Sciences Building, 3rd Floor, 1 King' s College Circle, Toronto, Ontario M5S 1A8 (Canada); Ferguson, K. A. [Toronto Western Research Institute, University Health Network, Krembil Discovery Tower, Toronto Western Hospital, 60 Leonard Street, 7th floor, 7KD411, Toronto, Ontario M5T 2S8 (Canada); Department of Physiology, University of Toronto Medical Sciences Building, 3rd Floor, 1 King' s College Circle, Toronto, Ontario M5S 1A8 (Canada)

    2013-12-15

    There is an undisputed need and requirement for theoretical and computational studies in Neuroscience today. Furthermore, it is clear that oscillatory dynamical output from brain networks is representative of various behavioural states, and it is becoming clear that one could consider these outputs as measures of normal and pathological brain states. Although mathematical modeling of oscillatory dynamics in the context of neurological disease exists, it is a highly challenging endeavour because of the many levels of organization in the nervous system. This challenge is coupled with the increasing knowledge of cellular specificity and network dysfunction that is associated with disease. Recently, whole hippocampus in vitro preparations from control animals have been shown to spontaneously express oscillatory activities. In addition, when using preparations derived from animal models of disease, these activities show particular alterations. These preparations present an opportunity to address challenges involved with using models to gain insight because of easier access to simultaneous cellular and network measurements, and pharmacological modulations. We propose that by developing and using models with direct links to experiment at multiple levels, which at least include cellular and microcircuit, a cycling can be set up and used to help us determine critical mechanisms underlying neurological disease. We illustrate our proposal using our previously developed inhibitory network models in the context of these whole hippocampus preparations and show the importance of having direct links at multiple levels.

  20. Psychometric properties of Positive and Negative Affect Schedule (PANAS) original and short forms in an African American community sample.

    Science.gov (United States)

    Merz, Erin L; Malcarne, Vanessa L; Roesch, Scott C; Ko, Celine M; Emerson, Marc; Roma, Vincenzo G; Sadler, Georgia Robins

    2013-12-01

    The Positive and Negative Affect Schedule (PANAS) has been widely used as a self-report measure of affect in community and clinical contexts. However, evaluations of the psychometric properties of PANAS scores have been limited in diverse ethnic groups. Several short forms of the PANAS have also been proposed, but very little is known about the psychometric properties of these versions. The present study investigated the psychometric properties, including the factor structure of the original PANAS and two short forms in an African American community sample (N=239). Descriptive, internal consistency reliability, factorial validity, and measurement invariance analyses were conducted. All PANAS subscales from the original and short forms had adequate internal consistency. For the original PANAS, the model specifying three correlated factors (Positive Affect, Afraid, Upset) with correlated uniquenesses from redundant items provided the best fit to the data. However, the two-factor model (Positive Affect, Negative Affect) with correlated uniquenesses was also supported. For both short forms, the two-factor model with correlated uniquenesses fit the data best. Factors from all forms were generally invariant across age and gender, although there was some minor invariance at the item level. Participants were from a limited geographic area and one ethnic group. Indicators of anxiety, depression, and cultural characteristics were not measured. The factor structure was replicated, suggesting no immediate concerns regarding the valid interpretation of PANAS scores. The results support the reliability and validity of the PANAS and its short forms for use among African Americans. © 2013 Elsevier B.V. All rights reserved.