Directory of Open Access Journals (Sweden)
Rolf Schubert
2004-12-01
Full Text Available Liposomes are used for drug carriers meaning that drugs are incorporated in the membrane or the vesicle of the liposomes. In this study, liposomes were prepared from mixed micelles, consisting of phosphatidylcholine, without or with cholesterol and sodium cholate was added in several ratios namely 0.44; 0.55; 0.63; 0.70; 0.90 and 1.10. After the preparation, the sodium cholate has been removed by a dialysis membrane, using the Hemoflow High Flux, which is generally used for haemodialysis. The Hemoflow High Flux is a tool in an effort to obtain a simple, quick, effective method for removing sodium cholate in the process of preparing liposomes. The effectiveness of this tool was proved by the particle size of the liposome which was measured by the Malvern Particle Sizer. The particle size of the liposome consisting of phosphatidylcholine (PC without cholesterol and with cholesterol was 63-68 nm at all ratios and approximately 125 nm at the ratio of 0.55; 0.63; 0.70, respectively. The particle size of the liposome tended to be smaller after dialyzing, although the concentration of lipids tended to increase. However, a large amount of buffer solution has to be used with this method.
Zachary Patterson
2008-01-01
Social scientists appear to be divided into two camps: those who use models and those who do not. In order to understand this phenomenon, a clear understanding of what a model is is required. Unfortunately, this is more complicated than one might think. To be sure, few social scientists would have trouble identifying what they consider to be a model: defining what a model is, however, is more difficult. To echo Associate Justice Potter Stewart's famous quote about pornography, most social...
DEFF Research Database (Denmark)
Juel-Christiansen, Carsten
2005-01-01
Artiklen fremhæver den visuelle rotation - billeder, tegninger, modeller, værker - som det privilligerede medium i kommunikationen af ideer imellem skabende arkitekter......Artiklen fremhæver den visuelle rotation - billeder, tegninger, modeller, værker - som det privilligerede medium i kommunikationen af ideer imellem skabende arkitekter...
Spädtke, P
2013-01-01
Modeling of technical machines became a standard technique since computer became powerful enough to handle the amount of data relevant to the specific system. Simulation of an existing physical device requires the knowledge of all relevant quantities. Electric fields given by the surrounding boundary as well as magnetic fields caused by coils or permanent magnets have to be known. Internal sources for both fields are sometimes taken into account, such as space charge forces or the internal magnetic field of a moving bunch of charged particles. Used solver routines are briefly described and some bench-marking is shown to estimate necessary computing times for different problems. Different types of charged particle sources will be shown together with a suitable model to describe the physical model. Electron guns are covered as well as different ion sources (volume ion sources, laser ion sources, Penning ion sources, electron resonance ion sources, and H$^-$-sources) together with some remarks on beam transport.
African Journals Online (AJOL)
distress, or culture—bound syndrome, not listed in DSM—lV. It may correspond to various DS/Vl-ll/ disorders, depending on its exact clinical presentation, e.g. dissociative disorder, adiustment disorder, or schizophrenia.1g As with other local idioms ot distress, the explanatory model takes precedence over the descriptive ...
Lesh, Richard; Carmona, Guadalupe; Post, Thomas
In this workshop, we will continue to reflect on a models and modeling perspective to understand how students and teachers learn and reason about real life situations encountered in a mathematics and science classroom. We will discuss the idea of a model as a conceptual system that is expressed by using external representational media, and that is…
DEFF Research Database (Denmark)
Cameron, Ian; Gani, Rafiqul
2011-01-01
requirements; model construction; model solution; model verification; model validation and finally model deployment and maintenance. Within the adopted methodology, each step is discussedthrough the consideration of key issues and questions relevant to the modelling activity. Practical advice, based on many...
ten Cate, J.M.
2015-01-01
Developing experimental models to understand dental caries has been the theme in our research group. Our first, the pH-cycling model, was developed to investigate the chemical reactions in enamel or dentine, which lead to dental caries. It aimed to leverage our understanding of the fluoride mode of
DEFF Research Database (Denmark)
Carlson, Kerstin
The International Criminal Tribunal for the former Yugoslavia (ICTY) was the first and most celebrated of a wave of international criminal tribunals (ICTs) built in the 1990s designed to advance liberalism through international criminal law. Model(ing) Justice examines the case law of the ICTY...
Simonse, W.L.
2014-01-01
Business model design does not always produce a “design” or “model” as the expected result. However, when designers are involved, a visual model or artifact is produced. To assist strategic managers in thinking about how they can act, the designers’ challenge is to combine both strategy and design
Modelling SDL, Modelling Languages
Directory of Open Access Journals (Sweden)
Michael Piefel
2007-02-01
Full Text Available Today's software systems are too complex to implement them and model them using only one language. As a result, modern software engineering uses different languages for different levels of abstraction and different system aspects. Thus to handle an increasing number of related or integrated languages is the most challenging task in the development of tools. We use object oriented metamodelling to describe languages. Object orientation allows us to derive abstract reusable concept definitions (concept classes from existing languages. This language definition technique concentrates on semantic abstractions rather than syntactical peculiarities. We present a set of common concept classes that describe structure, behaviour, and data aspects of high-level modelling languages. Our models contain syntax modelling using the OMG MOF as well as static semantic constraints written in OMG OCL. We derive metamodels for subsets of SDL and UML from these common concepts, and we show for parts of these languages that they can be modelled and related to each other through the same abstract concepts.
Model-model Evaluasi Pendidikan
Qomari, Rohmad
2008-01-01
On learning literature, there many kind of learning model design, for example model developed by Winarno Surakhmad, Winkel, Hisyam Zaini et al., Briggs and Wager, Gerlach and Ely, and Kemp. Those models design have component and pattern that different each other, from model that have dominant quantitative measure like measurement model and model that using qualitative approach as illuminative model. By studying many models and broaden view not only to one model approach, and even combine (m...
DEFF Research Database (Denmark)
Poulsen, Helle
1996-01-01
This paper presents a functional modelling method called Actant Modelling rooted in linguistics and semiotics. Actant modelling can be integrated with Multilevel Flow Modelling (MFM) in order to give an interpretation of actants.......This paper presents a functional modelling method called Actant Modelling rooted in linguistics and semiotics. Actant modelling can be integrated with Multilevel Flow Modelling (MFM) in order to give an interpretation of actants....
Anaïs Schaeffer
2012-01-01
By analysing the production of mesons in the forward region of LHC proton-proton collisions, the LHCf collaboration has provided key information needed to calibrate extremely high-energy cosmic ray models. Average transverse momentum (pT) as a function of rapidity loss ∆y. Black dots represent LHCf data and the red diamonds represent SPS experiment UA7 results. The predictions of hadronic interaction models are shown by open boxes (sibyll 2.1), open circles (qgsjet II-03) and open triangles (epos 1.99). Among these models, epos 1.99 shows the best overall agreement with the LHCf data. LHCf is dedicated to the measurement of neutral particles emitted at extremely small angles in the very forward region of LHC collisions. Two imaging calorimeters – Arm1 and Arm2 – take data 140 m either side of the ATLAS interaction point. “The physics goal of this type of analysis is to provide data for calibrating the hadron interaction models – the well-known &...
Directory of Open Access Journals (Sweden)
Tea Ya. Danelyan
2014-01-01
Full Text Available The article states the general principles of structural modeling in aspect of the theory of systems and gives the interrelation with other types of modeling to adjust them to the main directions of modeling. Mathematical methods of structural modeling, in particular method of expert evaluations are considered.
DEFF Research Database (Denmark)
Sales-Cruz, Mauricio; Piccolo, Chiara; Heitzig, Martina
2011-01-01
This chapter presents various types of constitutive models and their applications. There are 3 aspects dealt with in this chapter, namely: creation and solution of property models, the application of parameter estimation and finally application examples of constitutive models. A systematic...... procedure is introduced for the analysis and solution of property models. Models that capture and represent the temperature dependent behaviour of physical properties are introduced, as well as equation of state models (EOS) such as the SRK EOS. Modelling of liquid phase activity coefficients are also...... covered, illustrating several models such as the Wilson equation and NRTL equation, along with their solution strategies. A section shows how to use experimental data to regress the property model parameters using a least squares approach. A full model analysis is applied in each example that discusses...
Chang, CC
2012-01-01
Model theory deals with a branch of mathematical logic showing connections between a formal language and its interpretations or models. This is the first and most successful textbook in logical model theory. Extensively updated and corrected in 1990 to accommodate developments in model theoretic methods - including classification theory and nonstandard analysis - the third edition added entirely new sections, exercises, and references. Each chapter introduces an individual method and discusses specific applications. Basic methods of constructing models include constants, elementary chains, Sko
Healy, Richard W.; Scanlon, Bridget R.
2010-01-01
Simulation models are widely used in all types of hydrologic studies, and many of these models can be used to estimate recharge. Models can provide important insight into the functioning of hydrologic systems by identifying factors that influence recharge. The predictive capability of models can be used to evaluate how changes in climate, water use, land use, and other factors may affect recharge rates. Most hydrological simulation models, including watershed models and groundwater-flow models, are based on some form of water-budget equation, so the material in this chapter is closely linked to that in Chapter 2. Empirical models that are not based on a water-budget equation have also been used for estimating recharge; these models generally take the form of simple estimation equations that define annual recharge as a function of precipitation and possibly other climatic data or watershed characteristics.Model complexity varies greatly. Some models are simple accounting models; others attempt to accurately represent the physics of water movement through each compartment of the hydrologic system. Some models provide estimates of recharge explicitly; for example, a model based on the Richards equation can simulate water movement from the soil surface through the unsaturated zone to the water table. Recharge estimates can be obtained indirectly from other models. For example, recharge is a parameter in groundwater-flow models that solve for hydraulic head (i.e. groundwater level). Recharge estimates can be obtained through a model calibration process in which recharge and other model parameter values are adjusted so that simulated water levels agree with measured water levels. The simulation that provides the closest agreement is called the best fit, and the recharge value used in that simulation is the model-generated estimate of recharge.
Physical modeling versus numerical modeling
Blacquière, G.; Veldhuizen, E. van
2003-01-01
Despite the widespread use of numerical modeling, there is still room for physical modeling today for many reasons. E.g., physical modeling is based on real wave propagation whereas numerical modeling is based on algorithms which are by necessity simplified and discretized versions of the 'real
Model-model Perencanaan Strategik
Tatang M Amirin
2005-01-01
The process of strategic planning, used to be called as long-term planning, consists of several components, including strategic analysis, setting strategic direction (covering of mission, vision, and values), and action planning. Many writers develop models representing the steps of the strategic planning process, i.e. basic planning model, problem-based planning model, scenario model, and organic or self-organizing model.
DEFF Research Database (Denmark)
Bækgaard, Lars
2001-01-01
The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... are dynamic and we present a modeling approach that can be used to model such dynamics.We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can...
Digital Repository Service at National Institute of Oceanography (India)
Unnikrishnan, A.S.; Manoj, N.T.
Various numerical models used to study the dynamics and horizontal distribution of salinity in Mandovi-Zuari estuaries, Goa, India is discussed in this chapter. Earlier, a one-dimensional network model was developed for representing the complex...
National Research Council Canada - National Science Library
Singh, V.P; Frevert, D.K
2006-01-01
This book spans a variety of modeling areas, outlining 24 models that represent a variety of characteristics, such as physical bases, comprehensiveness, broad-based applicability, and use of modern tools...
Turner, Raymond
2009-01-01
Computational models can be found everywhere in present day science and engineering. In providing a logical framework and foundation for the specification and design of specification languages, Raymond Turner uses this framework to introduce and study computable models. In doing so he presents the first systematic attempt to provide computational models with a logical foundation. Computable models have wide-ranging applications from programming language semantics and specification languages, through to knowledge representation languages and formalism for natural language semantics. They are al
DEFF Research Database (Denmark)
Sclütter, Flemming; Frigaard, Peter; Liu, Zhou
This report presents the model test results on wave run-up on the Zeebrugge breakwater under the simulated prototype storms. The model test was performed in January 2000 at the Hydraulics & Coastal Engineering Laboratory, Aalborg University. The detailed description of the model is given...
Bergsma, Wicher; Hagenaars, Jacques A
2009-01-01
Presents an overview of the basic principles of marginal modeling and offers a range of possible applications. This book includes many real world examples, explains the types of research questions for which marginal modeling is useful, and provides a description of how to apply marginal models for a great diversity of research questions.
DEFF Research Database (Denmark)
Blomhøj, Morten
2004-01-01
modelling, however, can be seen as a practice of teaching that place the relation between real life and mathematics into the centre of teaching and learning mathematics, and this is relevant at all levels. Modelling activities may motivate the learning process and help the learner to establish cognitive...... roots for the construction of important mathematical concepts. In addition competences for setting up, analysing and criticising modelling processes and the possible use of models is a formative aim in this own right for mathematics teaching in general education. The paper presents a theoretical...... framework, which has been used for designing modelling courses, analysing students’ modelling activities, identifying learning obstacles in the modelling process and to guide the teachers interaction with the students during their work. This will be illustrated with an example from a developmental project...
Russell, James J.; Theriot, Julie A.; Sood, Pranidhi; Marshall, Wallace F.; Laura F Landweber; Fritz-Laylin, Lillian; Polka, Jessica K.; Oliferenko, Snezhana; Gerbich, Therese; Gladfelter, Amy; Umen, James; Bezanilla, Magdalena; Lancaster, Madeline A.; He, Shuonan; Matthew C Gibson
2017-01-01
Model organisms are widely used in research as accessible and convenient systems to study a particular area or question in biology. Traditionally only a handful of organisms have been widely studied, but modern research tools are enabling researchers to extend the set of model organisms to include less-studied and more unusual systems. This Forum highlights a range of 'non-model model organisms' as emerging systems for tackling questions across the whole spectrum of biology (and beyond), the ...
Modelling in Business Model design
Simonse, W.L.
2013-01-01
It appears that business model design might not always produce a design or model as the expected result. However when designers are involved, a visual model or artefact is produced. To assist strategic managers in thinking about how they can act, the designers challenge is to combine strategy and
2016-01-01
This book provides a thorough introduction to the challenge of applying mathematics in real-world scenarios. Modelling tasks rarely involve well-defined categories, and they often require multidisciplinary input from mathematics, physics, computer sciences, or engineering. In keeping with this spirit of modelling, the book includes a wealth of cross-references between the chapters and frequently points to the real-world context. The book combines classical approaches to modelling with novel areas such as soft computing methods, inverse problems, and model uncertainty. Attention is also paid to the interaction between models, data and the use of mathematical software. The reader will find a broad selection of theoretical tools for practicing industrial mathematics, including the analysis of continuum models, probabilistic and discrete phenomena, and asymptotic and sensitivity analysis.
Energy Technology Data Exchange (ETDEWEB)
Braby, L.A.
1990-09-01
The biological effects of ionizing radiation exposure are the result of a complex sequence of physical, chemical, biochemical, and physiological interactions. One way to begin a search for an understanding of health effects of radiation is through the development of phenomenological models of the response. Many models have been presented and tested in the slowly evolving process of characterizing cellular response. A range of models covering different endpoints and phenomena has developed in parallel. Many of these models employ similar assumptions about some underlying processes while differing about the nature of others. An attempt is made to organize many of the models into groups with similar features and to compare the consequences of those features with the actual experimental observations. It is assumed that by showing that some assumptions are inconsistent with experimental observations, the job of devising and testing mechanistic models can be simplified. 43 refs., 13 figs.
DEFF Research Database (Denmark)
Larsen, Lars Bjørn; Vesterager, Johan
This report provides an overview of the existing models of global manufacturing, describes the required modelling views and associated methods and identifies tools, which can provide support for this modelling activity.The model adopted for global manufacturing is that of an extended enterprise....... One or more units from beyond the network may complement the extended enterprise. The common reference model for this extended enterprise will utilise GERAM (Generalised Enterprise Reference Architecture and Methodology) to provide an architectural framework for the modelling carried out within...... sharing many of the characteristics of a virtual enterprise. This extended enterprise will have the following characteristics: The extended enterprise is focused on satisfying the current customer requirement so that it has a limited life expectancy, but should be capable of being recreated to deal...
DEFF Research Database (Denmark)
Bækgaard, Lars
2001-01-01
are dynamic and we present a modeling approach that can be used to model such dynamics. We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can......The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... be characterized by their occurrence times and the participating books and borrowers. When we characterize events as information objects we focus on concepts like information structures. When viewed as change agents events are phenomena that trigger change. For example, when borrow event occurs books are moved...
Marco Antonio Moreira
1996-01-01
The mental models subject is presented particularly in the light of Johnson-Laird’s theory. Views from different authors are also presented but the emphasis lies in Johson-Laird’s approach, proposing mental models as a third path in the images x propositions debate. In this perspective, the nature, content, and typology of mental models are discussed, as well as the issue of conciousness and computability. In addition, the methodology of research studies are provided. Essentially, the aim of ...
Wenninger, Magnus J
2012-01-01
Well-illustrated, practical approach to creating star-faced spherical forms that can serve as basic structures for geodesic domes. Complete instructions for making models from circular bands of paper with just a ruler and compass. Discusses tessellation, or tiling, and how to make spherical models of the semiregular solids and concludes with a discussion of the relationship of polyhedra to geodesic domes and directions for building models of domes. "". . . very pleasant reading."" - Science. 1979 edition.
DEFF Research Database (Denmark)
Liu, Zhou; Frigaard, Peter
This report presents the model on wave run-up and run-down on the Zeebrugge breakwater under short-crested oblique wave attacks. The model test was performed in March-April 2000 at the Hydraulics & Coastal Engineering Laboratory, Aalborg University.......This report presents the model on wave run-up and run-down on the Zeebrugge breakwater under short-crested oblique wave attacks. The model test was performed in March-April 2000 at the Hydraulics & Coastal Engineering Laboratory, Aalborg University....
Directory of Open Access Journals (Sweden)
Marco Antonio Moreira
1996-12-01
Full Text Available The mental models subject is presented particularly in the light of Johnson-Laird’s theory. Views from different authors are also presented but the emphasis lies in Johson-Laird’s approach, proposing mental models as a third path in the images x propositions debate. In this perspective, the nature, content, and typology of mental models are discussed, as well as the issue of conciousness and computability. In addition, the methodology of research studies are provided. Essentially, the aim of the paper is to provide an introduction to the mental models topic, having science education research in mind.
DEFF Research Database (Denmark)
Nielsen, Mogens Peter; Shui, Wan; Johansson, Jens
2011-01-01
In this report a new turbulence model is presented.In contrast to the bulk of modern work, the model is a classical continuum model with a relatively simple constitutive equation. The constitutive equation is, as usual in continuum mechanics, entirely empirical. It has the usual Newton or Stokes...... term with stresses depending linearly on the strain rates. This term takes into account the transfer of linear momentum from one part of the fluid to another. Besides there is another term, which takes into account the transfer of angular momentum. Thus the model implies a new definition of turbulence...
Modeling Documents with Event Model
Directory of Open Access Journals (Sweden)
Longhui Wang
2015-08-01
Full Text Available Currently deep learning has made great breakthroughs in visual and speech processing, mainly because it draws lessons from the hierarchical mode that brain deals with images and speech. In the field of NLP, a topic model is one of the important ways for modeling documents. Topic models are built on a generative model that clearly does not match the way humans write. In this paper, we propose Event Model, which is unsupervised and based on the language processing mechanism of neurolinguistics, to model documents. In Event Model, documents are descriptions of concrete or abstract events seen, heard, or sensed by people and words are objects in the events. Event Model has two stages: word learning and dimensionality reduction. Word learning is to learn semantics of words based on deep learning. Dimensionality reduction is the process that representing a document as a low dimensional vector by a linear mode that is completely different from topic models. Event Model achieves state-of-the-art results on document retrieval tasks.
Flores, J.; Kiss, S.; Cano, P.; Nijholt, Antinus; Zwiers, Jakob
2003-01-01
We concentrate our efforts on building virtual modelling environments where the content creator uses controls (widgets) as an interactive adjustment modality for the properties of the edited objects. Besides the advantage of being an on-line modelling approach (visualised just like any other on-line
Poortman, Sybilla; Sloep, Peter
2006-01-01
Educational models describes a case study on a complex learning object. Possibilities are investigated for using this learning object, which is based on a particular educational model, outside of its original context. Furthermore, this study provides advice that might lead to an increase in
Jongerden, M.R.; Haverkort, Boudewijn R.H.M.
2008-01-01
The use of mobile devices is often limited by the capacity of the employed batteries. The battery lifetime determines how long one can use a device. Battery modeling can help to predict, and possibly extend this lifetime. Many different battery models have been developed over the years. However,
DEFF Research Database (Denmark)
Løssing, Ulrik
1986-01-01
Ulrik Løssing har redigeret, illustreret og oversat: "Scribe Modeller System, Sheffield, november 1985" af forfatterne: Cedric Green, David Cooper og John Wells.......Ulrik Løssing har redigeret, illustreret og oversat: "Scribe Modeller System, Sheffield, november 1985" af forfatterne: Cedric Green, David Cooper og John Wells....
DEFF Research Database (Denmark)
Ravn, Anders P.; Staunstrup, Jørgen
1994-01-01
This paper proposes a model for specifying interfaces between concurrently executing modules of a computing system. The model does not prescribe a particular type of communication protocol and is aimed at describing interfaces between both software and hardware modules or a combination of the two...
DEFF Research Database (Denmark)
Gøtze, Jens Peter; Krentz, Andrew
2014-01-01
In this issue of Cardiovascular Endocrinology, we are proud to present a broad and dedicated spectrum of reviews on animal models in cardiovascular disease. The reviews cover most aspects of animal models in science from basic differences and similarities between small animals and the human...... pathology, to biomarkers in diagnosis and prognostic evaluation, to drug testing and targeted medicine....
DEFF Research Database (Denmark)
Højgaard, Tomas; Hansen, Rune
The purpose of this paper is to introduce Didactical Modelling as a research methodology in mathematics education. We compare the methodology with other approaches and argue that Didactical Modelling has its own specificity. We discuss the methodological “why” and explain why we find it useful...
DEFF Research Database (Denmark)
Kindler, Ekkart
2009-01-01
, these notations have been extended in order to increase expressiveness and to be more competitive. This resulted in an increasing number of notations and formalisms for modelling business processes and in an increase of the different modelling constructs provided by modelling notations, which makes it difficult...... to compare modelling notations and to make transformations between them. One of the reasons is that, in each notation, the new concepts are introduced in a different way by extending the already existing constructs. In this chapter, we go the opposite direction: We show that it is possible to add most...... constructs and how they can be combined with more advanced constructs. Second, it will help combining different modelling notations with each other. Note that, though we introduce a notation for blocks in this chapter, we are not so much interested in promoting this notation here. The notation should just...
Energy Technology Data Exchange (ETDEWEB)
Veronica J. Rutledge
2013-01-01
The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior and feedback loops. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes will provide substantial cost savings and many technical benefits. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed within Multi-physics Object Oriented Simulation Environment (MOOSE) developed at the Idaho National Laboratory (INL). Off-gas Separation and REcoverY (OSPREY) models the adsorption of off-gas constituents for dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions. Inputs to the model include gas, sorbent, and column properties, equilibrium and kinetic data, and inlet conditions. The simulation outputs component concentrations along the column length as a function of time from which breakthrough data is obtained. The breakthrough data can be used to determine bed capacity, which in turn can be used to size columns. It also outputs temperature along the column length as a function of time and pressure drop along the column length. Experimental data and parameters were input into the adsorption model to develop models specific for krypton adsorption. The same can be done for iodine, xenon, and tritium. The model will be validated with experimental breakthrough curves. Customers will be given access to
DEFF Research Database (Denmark)
Kreiner, Svend; Christensen, Karl Bang
Rasch models; Partial Credit models; Rating Scale models; Item bias; Differential item functioning; Local independence; Graphical models......Rasch models; Partial Credit models; Rating Scale models; Item bias; Differential item functioning; Local independence; Graphical models...
Modeling complexes of modeled proteins.
Anishchenko, Ivan; Kundrotas, Petras J; Vakser, Ilya A
2017-03-01
Structural characterization of proteins is essential for understanding life processes at the molecular level. However, only a fraction of known proteins have experimentally determined structures. This fraction is even smaller for protein-protein complexes. Thus, structural modeling of protein-protein interactions (docking) primarily has to rely on modeled structures of the individual proteins, which typically are less accurate than the experimentally determined ones. Such "double" modeling is the Grand Challenge of structural reconstruction of the interactome. Yet it remains so far largely untested in a systematic way. We present a comprehensive validation of template-based and free docking on a set of 165 complexes, where each protein model has six levels of structural accuracy, from 1 to 6 Å C α RMSD. Many template-based docking predictions fall into acceptable quality category, according to the CAPRI criteria, even for highly inaccurate proteins (5-6 Å RMSD), although the number of such models (and, consequently, the docking success rate) drops significantly for models with RMSD > 4 Å. The results show that the existing docking methodologies can be successfully applied to protein models with a broad range of structural accuracy, and the template-based docking is much less sensitive to inaccuracies of protein models than the free docking. Proteins 2017; 85:470-478. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Blacher, René
2010-01-01
Ce rapport complete les deux rapports précédents et apporte une explication plus simple aux résultats précédents : à savoir la preuve que les suites obtenues sont aléatoires.; In previous reports, we have show how to transform a text $y_n$ in a random sequence by using functions of Fibonacci $T_q$. Now, in this report, we obtain a clearer result by proving that $T_q(y_n)$ has the IID model as correct model. But, it is necessary to define correctly a correct model. Then, we study also this pro...
Hodges, Wilfrid
1993-01-01
An up-to-date and integrated introduction to model theory, designed to be used for graduate courses (for students who are familiar with first-order logic), and as a reference for more experienced logicians and mathematicians.
National Oceanic and Atmospheric Administration, Department of Commerce — Computer simulations of past climate. Variables provided as model output are described by parameter keyword. In some cases the parameter keywords are a subset of all...
Searle, Shayle R
2012-01-01
This 1971 classic on linear models is once again available--as a Wiley Classics Library Edition. It features material that can be understood by any statistician who understands matrix algebra and basic statistical methods.
EPA's modeling community is working to gain insights into certain parts of a physical, biological, economic, or social system by conducting environmental assessments for Agency decision making to complex environmental issues.
DEFF Research Database (Denmark)
Vestergaard, Kristian
The development of the digital computer has been of great importance for the hydraulic engineer. Through many centuries hydraulic engineering was based on practical know-how, obtained through many hundred years experience. Gradually mathematical theories were introduced and accepted among...... the engineers, but as the scale and the complexity of the hydraulic works increased, the mathematical models became so complex that a mathematical solution could not be obtained. This created a demand for new methods and again the experimental investigation became popular, but this time as measurements on small......-scale models. But still the scale and complexity of hydraulic works were increasing, and soon even small-scale models reached a natural limit for some applications. In the mean time the modern computer was developed, and it became possible to solve complex mathematical models by use of computer-based numerical...
Regardt, Olle; Rönnbäck, Lars; Bergholtz, Maria; Johannesson, Paul; Wohed, Petia
Maintaining and evolving data warehouses is a complex, error prone, and time consuming activity. The main reason for this state of affairs is that the environment of a data warehouse is in constant change, while the warehouse itself needs to provide a stable and consistent interface to information spanning extended periods of time. In this paper, we propose a modeling technique for data warehousing, called anchor modeling, that offers non-destructive extensibility mechanisms, thereby enabling robust and flexible management of changes in source systems. A key benefit of anchor modeling is that changes in a data warehouse environment only require extensions, not modifications, to the data warehouse. This ensures that existing data warehouse applications will remain unaffected by the evolution of the data warehouse, i.e. existing views and functions will not have to be modified as a result of changes in the warehouse model.
DEFF Research Database (Denmark)
Lasrado, Lester Allan; Vatrapu, Ravi
2016-01-01
effects, unicausal reduction, and case specificity. Based on the developments in set theoretical thinking in social sciences and employing methods like Qualitative Comparative Analysis (QCA), Necessary Condition Analysis (NCA), and set visualization techniques, in this position paper, we propose...... and demonstrate a new approach to maturity models in the domain of Information Systems. This position paper describes the set-theoretical approach to maturity models, presents current results and outlines future research work....
Accelerated life models modeling and statistical analysis
Bagdonavicius, Vilijandas
2001-01-01
Failure Time DistributionsIntroductionParametric Classes of Failure Time DistributionsAccelerated Life ModelsIntroductionGeneralized Sedyakin's ModelAccelerated Failure Time ModelProportional Hazards ModelGeneralized Proportional Hazards ModelsGeneralized Additive and Additive-Multiplicative Hazards ModelsChanging Shape and Scale ModelsGeneralizationsModels Including Switch-Up and Cycling EffectsHeredity HypothesisSummaryAccelerated Degradation ModelsIntroductionDegradation ModelsModeling the Influence of Explanatory Varia
Energy Technology Data Exchange (ETDEWEB)
Curtis, S.B.
1990-09-01
Several models and theories are reviewed that incorporate the idea of radiation-induced lesions (repairable and/or irreparable) that can be related to molecular lesions in the DNA molecule. Usually the DNA double-strand or chromatin break is suggested as the critical lesion. In the models, the shoulder on the low-LET survival curve is hypothesized as being due to one (or more) of the following three mechanisms: (1) interaction'' of lesions produced by statistically independent particle tracks; (2) nonlinear (i.e., linear-quadratic) increase in the yield of initial lesions, and (3) saturation of repair processes at high dose. Comparisons are made between the various approaches. Several significant advances in model development are discussed; in particular, a description of the matrix formulation of the Markov versions of the RMR and LPL models is given. The more advanced theories have incorporated statistical fluctuations in various aspects of the energy-loss and lesion-formation process. An important direction is the inclusion of physical and chemical processes into the formulations by incorporating relevant track structure theory (Monte Carlo track simulations) and chemical reactions of radiation-induced radicals. At the biological end, identification of repair genes and how they operate as well as a better understanding of how DNA misjoinings lead to lethal chromosome aberrations are needed for appropriate inclusion into the theories. More effort is necessary to model the complex end point of radiation-induced carcinogenesis.
Energy Technology Data Exchange (ETDEWEB)
Curtis, S.B.
1990-09-01
Several models and theories are reviewed that incorporate the idea of radiation-induced lesions (repairable and/or irreparable) that can be related to molecular lesions in the DNA molecule. Usually the DNA double-strand or chromatin break is suggested as the critical lesion. In the models, the shoulder on the low-LET survival curve is hypothesized as being due to one (or more) of the following three mechanisms: (1) ``interaction`` of lesions produced by statistically independent particle tracks; (2) nonlinear (i.e., linear-quadratic) increase in the yield of initial lesions, and (3) saturation of repair processes at high dose. Comparisons are made between the various approaches. Several significant advances in model development are discussed; in particular, a description of the matrix formulation of the Markov versions of the RMR and LPL models is given. The more advanced theories have incorporated statistical fluctuations in various aspects of the energy-loss and lesion-formation process. An important direction is the inclusion of physical and chemical processes into the formulations by incorporating relevant track structure theory (Monte Carlo track simulations) and chemical reactions of radiation-induced radicals. At the biological end, identification of repair genes and how they operate as well as a better understanding of how DNA misjoinings lead to lethal chromosome aberrations are needed for appropriate inclusion into the theories. More effort is necessary to model the complex end point of radiation-induced carcinogenesis.
Eck, Christof; Knabner, Peter
2017-01-01
Mathematical models are the decisive tool to explain and predict phenomena in the natural and engineering sciences. With this book readers will learn to derive mathematical models which help to understand real world phenomena. At the same time a wealth of important examples for the abstract concepts treated in the curriculum of mathematics degrees are given. An essential feature of this book is that mathematical structures are used as an ordering principle and not the fields of application. Methods from linear algebra, analysis and the theory of ordinary and partial differential equations are thoroughly introduced and applied in the modeling process. Examples of applications in the fields electrical networks, chemical reaction dynamics, population dynamics, fluid dynamics, elasticity theory and crystal growth are treated comprehensively.
DEFF Research Database (Denmark)
2012-01-01
The relationship between representation and the represented is examined here through the notion of persistent modelling. This notion is not novel to the activity of architectural design if it is considered as describing a continued active and iterative engagement with design concerns – an evident...... characteristic of architectural practice. But the persistence in persistent modelling can also be understood to apply in other ways, reflecting and anticipating extended roles for representation. This book identifies three principle areas in which these extensions are becoming apparent within contemporary....... It also provides critical insight into the use of contemporary modelling tools and methods, together with an examination of the implications their use has within the territories of architectural design, realisation and experience....
DEFF Research Database (Denmark)
Nash, Ulrik William
2014-01-01
Firms consist of people who make decisions to achieve goals. How do these people develop the expectations which underpin the choices they make? The lens model provides one answer to this question. It was developed by cognitive psychologist Egon Brunswik (1952) to illustrate his theory of probabil......Firms consist of people who make decisions to achieve goals. How do these people develop the expectations which underpin the choices they make? The lens model provides one answer to this question. It was developed by cognitive psychologist Egon Brunswik (1952) to illustrate his theory...... of probabilistic functionalism, and concerns the environment and the mind, and adaptation by the latter to the former. This entry is about the lens model, and probabilistic functionalism more broadly. Focus will mostly be on firms and their employees, but, to fully appreciate the scope, we have to keep in mind...
DEFF Research Database (Denmark)
2012-01-01
The relationship between representation and the represented is examined here through the notion of persistent modelling. This notion is not novel to the activity of architectural design if it is considered as describing a continued active and iterative engagement with design concerns – an evident....... It also provides critical insight into the use of contemporary modelling tools and methods, together with an examination of the implications their use has within the territories of architectural design, realisation and experience....... characteristic of architectural practice. But the persistence in persistent modelling can also be understood to apply in other ways, reflecting and anticipating extended roles for representation. This book identifies three principle areas in which these extensions are becoming apparent within contemporary...
2012-01-01
Background This work focuses on the computational modelling of osteomyelitis, a bone pathology caused by bacteria infection (mostly Staphylococcus aureus). The infection alters the RANK/RANKL/OPG signalling dynamics that regulates osteoblasts and osteoclasts behaviour in bone remodelling, i.e. the resorption and mineralization activity. The infection rapidly leads to severe bone loss, necrosis of the affected portion, and it may even spread to other parts of the body. On the other hand, osteoporosis is not a bacterial infection but similarly is a defective bone pathology arising due to imbalances in the RANK/RANKL/OPG molecular pathway, and due to the progressive weakening of bone structure. Results Since both osteoporosis and osteomyelitis cause loss of bone mass, we focused on comparing the dynamics of these diseases by means of computational models. Firstly, we performed meta-analysis on a gene expression data of normal, osteoporotic and osteomyelitis bone conditions. We mainly focused on RANKL/OPG signalling, the TNF and TNF receptor superfamilies and the NF-kB pathway. Using information from the gene expression data we estimated parameters for a novel model of osteoporosis and of osteomyelitis. Our models could be seen as a hybrid ODE and probabilistic verification modelling framework which aims at investigating the dynamics of the effects of the infection in bone remodelling. Finally we discuss different diagnostic estimators defined by formal verification techniques, in order to assess different bone pathologies (osteopenia, osteoporosis and osteomyelitis) in an effective way. Conclusions We present a modeling framework able to reproduce aspects of the different bone remodeling defective dynamics of osteomyelitis and osteoporosis. We report that the verification-based estimators are meaningful in the light of a feed forward between computational medicine and clinical bioinformatics. PMID:23095605
Cardey, Sylviane
2013-01-01
In response to the need for reliable results from natural language processing, this book presents an original way of decomposing a language(s) in a microscopic manner by means of intra/inter‑language norms and divergences, going progressively from languages as systems to the linguistic, mathematical and computational models, which being based on a constructive approach are inherently traceable. Languages are described with their elements aggregating or repelling each other to form viable interrelated micro‑systems. The abstract model, which contrary to the current state of the art works in int
Koprivnikar, Teja
2017-01-01
Epidemiološki modeli širjenja nalezljivih bolezni so matematični modeli, ki poskušajo pojasniti, kako se širijo nalezljive bolezni. Eden najbolj znanih modelov je model SIR. Leta 1927 sta ga oblikovala Kermack in McKendrick, zapišemo pa ga lahko s sistemom treh diferencialnih enačb. Proučevanje le-teh nam omogoča napovedovanje obnašanja določene bolezni v populaciji in s tem napoved, ali bo epidemija izbruhnila ali ne. V diplomskem delu predstavimo in analiziramo omenjeni model ter poskušamo ...
Holmes, Jon L.
1999-06-01
Molecular modeling has trickled down from the realm of pharmaceutical and research laboratories into the realm of undergraduate chemistry instruction. It has opened avenues for the visualization of chemical concepts that previously were difficult or impossible to convey. I am sure that many of you have developed exercises using the various molecular modeling tools. It is the desire of this Journal to become an avenue for you to share these exercises among your colleagues. It is to this end that Ron Starkey has agreed to edit such a column and to publish not only the description of such exercises, but also the software documents they use. The WWW is the obvious medium to distribute this combination and so accepted submissions will appear online as a feature of JCE Internet. Typical molecular modeling exercise: finding conformation energies. Molecular Modeling Exercises and Experiments is the latest feature column of JCE Internet, joining Conceptual Questions and Challenge Problems, Hal's Picks, and Mathcad in the Chemistry Curriculum. JCE Internet continues to seek submissions in these areas of interest and submissions of general interest. If you have developed materials and would like to submit them, please see our Guide to Submissions for more information. The Chemical Education Resource Shelf, Equipment Buyers Guide, and WWW Site Review would also like to hear about chemistry textbooks and software, equipment, and WWW sites, respectively. Please consult JCE Internet Features to learn more about these resources at JCE Online. Email Announcements Would you like to be informed by email when the latest issue of the Journal is available online? when a new JCE Software title is shipping? when a new JCE Internet article has been published or is available for Open Review? when your subscription is about to expire? A new feature of JCE Online makes this possible. Visit our Guestbook to learn how. When you submit the form on this page, which includes your email address
Directory of Open Access Journals (Sweden)
Aarti Sharma
2009-01-01
Full Text Available The use of computational chemistry in the development of novel pharmaceuticals is becoming an increasingly important tool. In the past, drugs were simply screened for effectiveness. The recent advances in computing power and the exponential growth of the knowledge of protein structures have made it possible for organic compounds to be tailored to decrease the harmful side effects and increase the potency. This article provides a detailed description of the techniques employed in molecular modeling. Molecular modeling is a rapidly developing discipline, and has been supported by the dramatic improvements in computer hardware and software in recent years.
Building Models and Building Modelling
DEFF Research Database (Denmark)
Jørgensen, Kaj; Skauge, Jørn
2008-01-01
I rapportens indledende kapitel beskrives de primære begreber vedrørende bygningsmodeller og nogle fundamentale forhold vedrørende computerbaseret modulering bliver opstillet. Desuden bliver forskellen mellem tegneprogrammer og bygningsmodelleringsprogrammer beskrevet. Vigtige aspekter om......lering og bygningsmodeller. Det bliver understreget at modellering bør udføres på flere abstraktionsniveauer og i to dimensioner i den såkaldte modelleringsmatrix. Ud fra dette identificeres de primære faser af bygningsmodellering. Dernæst beskrives de basale karakteristika for bygningsmodeller. Heri...... inkluderes en præcisering af begreberne objektorienteret software og objektorienteret modeller. Det bliver fremhævet at begrebet objektbaseret modellering giver en tilstrækkelig og bedre forståelse. Endelig beskrives forestillingen om den ideale bygningsmodel som værende én samlet model, der anvendes gennem...
Goodwyn, Lauren; Salm, Sarah
2007-01-01
Teaching the anatomy of the muscle system to high school students can be challenging. Students often learn about muscle anatomy by memorizing information from textbooks or by observing plastic, inflexible models. Although these mediums help students learn about muscle placement, the mediums do not facilitate understanding regarding integration of…
DEFF Research Database (Denmark)
Jensen, Morten S.; Frigaard, Peter
In the following, results from model tests with Zeebrugge breakwater are presented. The objective with these tests is partly to investigate the influence on wave run-up due to a changing waterlevel during a storm. Finally, the influence on wave run-up due to an introduced longshore current...
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 7. Model Checking - Automated Verification of Computational Systems. Madhavan Mukund. General Article Volume 14 Issue 7 July 2009 pp 667-681. Fulltext. Click here to view fulltext PDF. Permanent link:
Energy Technology Data Exchange (ETDEWEB)
Hajj-Boutros, J. (Lebanese Univ., Mansourieh-El-Maten (Lebanon))
1989-04-01
An LRS Bianchi type II cosmological model is built with a state equation that is a function of the cosmic time t. The ratio p/{mu} is 1/3 when t {yields} 0 and is insignificant when t {yields} {infinity}. Thus, the matter content behaves like radiation for small t and like dust for large t.
Baart, F.; Donchyts, G.; van Dam, A.; Plieger, M.
2015-12-01
The emergence of interactive art has blurred the line between electronic, computer graphics and art. Here we apply this art form to numerical models. Here we show how the transformation of a numerical model into an interactive painting can both provide insights and solve real world problems. The cases that are used as an example include forensic reconstructions, dredging optimization, barrier design. The system can be fed using any source of time varying vector fields, such as hydrodynamic models. The cases used here, the Indian Ocean (HYCOM), the Wadden Sea (Delft3D Curvilinear), San Francisco Bay (3Di subgrid and Delft3D Flexible Mesh), show that the method used is suitable for different time and spatial scales. High resolution numerical models become interactive paintings by exchanging their velocity fields with a high resolution (>=1M cells) image based flow visualization that runs in a html5 compatible web browser. The image based flow visualization combines three images into a new image: the current image, a drawing, and a uv + mask field. The advection scheme that computes the resultant image is executed in the graphics card using WebGL, allowing for 1M grid cells at 60Hz performance on mediocre graphic cards. The software is provided as open source software. By using different sources for a drawing one can gain insight into several aspects of the velocity fields. These aspects include not only the commonly represented magnitude and direction, but also divergence, topology and turbulence .
Indian Academy of Sciences (India)
Improper practices of land use and land cover (LULC) including deforestation, expansion of agriculture and infrastructure development are deteriorating watershed conditions. Here, we have utilized remote sensing and GIS tools to study LULC dynamics using Cellular Automata (CA)–Markov model and pre- dicted the ...
DEFF Research Database (Denmark)
Bork Petersen, Franziska
2013-01-01
catwalks. Vibskov’s catwalk induces what the dance scholar Gabriele Brandstetter has labelled a ‘defigurative choregoraphy’: a straying from definitions, which exist in ballet as in other movement-based genres, of how a figure should move and appear (1998). The catwalk scenography in this instance...... focus centres on how the catwalk scenography evokes a ‘defiguration’ of the walking models and to what effect. Vibskov’s mobile catwalk draws attention to the walk, which is a key element of models’ performance but which usually functions in fashion shows merely to present clothes in the most...... advantageous manner. Stepping on the catwalk’s sloping, moving surfaces decelerates the models’ walk and makes it cautious, hesitant and shaky: suddenly the models lack exactly the affirmative, staccato, striving quality of motion, and the condescending expression that they perform on most contemporary...
DEFF Research Database (Denmark)
2012-01-01
The relationship between representation and the represented is examined here through the notion of persistent modelling. This notion is not novel to the activity of architectural design if it is considered as describing a continued active and iterative engagement with design concerns – an evident....... It also provides critical insight into the use of contemporary modelling tools and methods, together with an examination of the implications their use has within the territories of architectural design, realisation and experience....... on this subject, this book makes essential reading for anyone considering new ways of thinking about architecture. In drawing upon both historical and contemporary perspectives this book provides evidence of the ways in which relations between representation and the represented continue to be reconsidered...
Barr, Michael
2002-01-01
Acyclic models is a method heavily used to analyze and compare various homology and cohomology theories appearing in topology and algebra. This book is the first attempt to put together in a concise form this important technique and to include all the necessary background. It presents a brief introduction to category theory and homological algebra. The author then gives the background of the theory of differential modules and chain complexes over an abelian category to state the main acyclic models theorem, generalizing and systemizing the earlier material. This is then applied to various cohomology theories in algebra and topology. The volume could be used as a text for a course that combines homological algebra and algebraic topology. Required background includes a standard course in abstract algebra and some knowledge of topology. The volume contains many exercises. It is also suitable as a reference work for researchers.
Directory of Open Access Journals (Sweden)
Aarti Sharma
2009-12-01
Full Text Available
DEFF Research Database (Denmark)
This book reflects and expands on the current trend in the building industry to understand, simulate and ultimately design buildings by taking into consideration the interlinked elements and forces that act on them. This approach overcomes the traditional, exclusive focus on building tasks, while....... The chapter authors were invited speakers at the 5th Symposium "Modelling Behaviour", which took place at the CITA in Copenhagen in September 2015....
DEFF Research Database (Denmark)
Arnoldi, Jakob
The article discusses the use of algorithmic models for so-called High Frequency Trading (HFT) in finance. HFT is controversial yet widespread in modern financial markets. It is a form of automated trading technology which critics among other things claim can lead to market manipulation. Drawing....... The article analyses these challenges and argues that we witness a new post-social form of human-technology interaction that will lead to a reconfiguration of professional codes for financial trading....
Energy Technology Data Exchange (ETDEWEB)
Plimpton, Steven James; Heffernan, Julieanne; Sasaki, Darryl Yoshio; Frischknecht, Amalie Lucile; Stevens, Mark Jackson; Frink, Laura J. Douglas
2005-11-01
Understanding the properties and behavior of biomembranes is fundamental to many biological processes and technologies. Microdomains in biomembranes or ''lipid rafts'' are now known to be an integral part of cell signaling, vesicle formation, fusion processes, protein trafficking, and viral and toxin infection processes. Understanding how microdomains form, how they depend on membrane constituents, and how they act not only has biological implications, but also will impact Sandia's effort in development of membranes that structurally adapt to their environment in a controlled manner. To provide such understanding, we created physically-based models of biomembranes. Molecular dynamics (MD) simulations and classical density functional theory (DFT) calculations using these models were applied to phenomena such as microdomain formation, membrane fusion, pattern formation, and protein insertion. Because lipid dynamics and self-organization in membranes occur on length and time scales beyond atomistic MD, we used coarse-grained models of double tail lipid molecules that spontaneously self-assemble into bilayers. DFT provided equilibrium information on membrane structure. Experimental work was performed to further help elucidate the fundamental membrane organization principles.
MODEL-MODEL PENILAIAN SEKURITAS
Imron Rosyadi
2006-01-01
The valuation of securities is very important, it caused by the target of financial management that was to maximize the wealth of stockholder by means of maximize value of the firm. In this article, the writer showed the valuation models of securities such as, obligation, common stock, and preference stock. The obligation value is present value from annuity (payment of fixed interest rate each period) and added by present value of principal loan. Whereas in valuation of stock, at ...
From Reference Model to Component Model
Albani, Antonia; Zaha, Johannes Maria
2005-01-01
Stable component models are an essential prerequisite for developingcustomer-individual business applications. Thereby the information for theidentification and specification of their components is gained from domainmodels. Reference models constitute a potential source for building enterprisespecificdomain models. Based on the analysis of existing reference models,this article shows how information available through reference models can beused for the development of stable component models. ...
DEFF Research Database (Denmark)
Stubkjær, Erik
2005-01-01
to the modeling of an industrial sector, as it aims at rendering the basic concepts that relate to the domain of real estate and the pertinent human activities. The palpable objects are pieces of land and buildings, documents, data stores and archives, as well as persons in their diverse roles as owners, holders...... of assets, experts, and holders of authority. More subtle objects are rights and restrictions, which relate persons through enforceable rules and commitments. The objective of this fabric of complex relations is to provide a stable and yet flexible frame for legal-economic dispositions that are related...
1989-01-01
A wooden model of the ALEPH experiment and its cavern. ALEPH was one of 4 experiments at CERN's 27km Large Electron Positron collider (LEP) that ran from 1989 to 2000. During 11 years of research, LEP's experiments provided a detailed study of the electroweak interaction. Measurements performed at LEP also proved that there are three – and only three – generations of particles of matter. LEP was closed down on 2 November 2000 to make way for the construction of the Large Hadron Collider in the same tunnel. The cavern and detector are in separate locations - the cavern is stored at CERN and the detector is temporarily on display in Glasgow physics department. Both are available for loan.
Directory of Open Access Journals (Sweden)
Boštjan Kerbler
2006-01-01
Full Text Available The paper systematically describes special regression methods – discrete choice models – known as probability models. The meaning of models and their methodological characteristics are described, as well as different types of models, especially binary-choice models and censored regression models. We considered three most commonly used approaches to estimating such models – logit, probit and tobit model.
Afsarmanesh, H.; Camarinha-Matos, L.M.; Camarinha-Matos, L.M.; Afsarmanesh, H.
2008-01-01
A framework is defined for ARCON reference modeling, introducing multiple modeling perspectives of: Environment characteristics, life cycle stages, and modeling intents. This novel modeling framework takes into account contributions from previous related works, mainly on enterprise modeling, and
Model Manipulation for End-User Modelers
DEFF Research Database (Denmark)
Acretoaie, Vlad
, and proposes the VM* family of model manipulation languages addressing them. This family consists of the Visual Model Query Language (VMQL), the Visual Model Constraint Language (VMCL), and the Visual Model Transformation Language (VMTL). They allow modelers to specify and execute queries, constraints......End-user modelers are domain experts who create and use models as part of their work. They are typically not Software Engineers, and have little or no programming and meta-modeling experience. However, using model manipulation languages developed in the context of Model-Driven Engineering often...... integration, the VM* Runtime is deployed as a collection of lightweight Web Services. The claim that VM* languages offer end-user modelers superior learnability compared to existing model manipulation languages is verified empirically via user experiments complemented by qualitative evidence....
The IMACLIM model; Le modele IMACLIM
Energy Technology Data Exchange (ETDEWEB)
NONE
2003-07-01
This document provides annexes to the IMACLIM model which propose an actualized description of IMACLIM, model allowing the design of an evaluation tool of the greenhouse gases reduction policies. The model is described in a version coupled with the POLES, technical and economical model of the energy industry. Notations, equations, sources, processing and specifications are proposed and detailed. (A.L.B.)
Modelling live forensic acquisition
CSIR Research Space (South Africa)
Grobler, MM
2009-06-01
Full Text Available This paper discusses the development of a South African model for Live Forensic Acquisition - Liforac. The Liforac model is a comprehensive model that presents a range of aspects related to Live Forensic Acquisition. The model provides forensic...
Concept Modeling vs. Data modeling in Practice
DEFF Research Database (Denmark)
Madsen, Bodil Nistrup; Erdman Thomsen, Hanne
2015-01-01
This chapter shows the usefulness of terminological concept modeling as a first step in data modeling. First, we introduce terminological concept modeling with terminological ontologies, i.e. concept systems enriched with characteristics modeled as feature specifications. This enables a formal...... account of the inheritance of characteristics and allows us to introduce a number of principles and constraints which render concept modeling more coherent than earlier approaches. Second, we explain how terminological ontologies can be used as the basis for developing conceptual and logical data models....... We also show how to map from the various elements in the terminological ontology to elements in the data models, and explain the differences between the models. Finally the usefulness of terminological ontologies as a prerequisite for IT development and data modeling is illustrated with examples from...
Model-to-model interface for multiscale materials modeling
Energy Technology Data Exchange (ETDEWEB)
Antonelli, Perry Edward [Iowa State Univ., Ames, IA (United States)
2017-12-17
A low-level model-to-model interface is presented that will enable independent models to be linked into an integrated system of models. The interface is based on a standard set of functions that contain appropriate export and import schemas that enable models to be linked with no changes to the models themselves. These ideas are presented in the context of a specific multiscale material problem that couples atomistic-based molecular dynamics calculations to continuum calculations of fluid ow. These simulations will be used to examine the influence of interactions of the fluid with an adjacent solid on the fluid ow. The interface will also be examined by adding it to an already existing modeling code, Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) and comparing it with our own molecular dynamics code.
Longini, Ira M.; Morris, J. Glenn
2014-01-01
Mathematical modeling can be a valuable tool for studying infectious disease outbreak dynamics and simulating the effects of possible interventions. Here, we describe approaches to modeling cholera outbreaks and how models have been applied to explore intervention strategies, particularly in Haiti. Mathematical models can play an important role in formulating and evaluating complex cholera outbreak response options. Major challenges to cholera modeling are insufficient data for calibrating models and the need to tailor models for different outbreak scenarios. PMID:23412687
Zwiernik, Piotr
2017-01-01
Latent tree models are graphical models defined on trees, in which only a subset of variables is observed. They were first discussed by Judea Pearl as tree-decomposable distributions to generalise star-decomposable distributions such as the latent class model. Latent tree models, or their submodels, are widely used in: phylogenetic analysis, network tomography, computer vision, causal modeling, and data clustering. They also contain other well-known classes of models like hidden Markov models...
Air Quality Dispersion Modeling - Alternative Models
Models, not listed in Appendix W, that can be used in regulatory applications with case-by-case justification to the Reviewing Authority as noted in Section 3.2, Use of Alternative Models, in Appendix W.
Wake modelling combining mesoscale and microscale models
DEFF Research Database (Denmark)
Badger, Jake; Volker, Patrick; Prospathospoulos, J.
2013-01-01
In this paper the basis for introducing thrust information from microscale wake models into mesocale model wake parameterizations will be described. A classification system for the different types of mesoscale wake parameterizations is suggested and outlined. Four different mesoscale wake...
Uncertainty Modeling Via Frequency Domain Model Validation
Waszak, Martin R.; Andrisani, Dominick, II
1999-01-01
Abstract The majority of literature on robust control assumes that a design model is available and that the uncertainty model bounds the actual variations about the nominal model. However, methods for generating accurate design models have not received as much attention in the literature. The influence of the level of accuracy of the uncertainty model on closed loop performance has received even less attention. The research reported herein is an initial step in applying and extending the concept of model validation to the problem of obtaining practical uncertainty models for robust control analysis and design applications. An extension of model validation called 'sequential validation' is presented and applied to a simple spring-mass-damper system to establish the feasibility of the approach and demonstrate the benefits of the new developments.
From Numeric Models to Granular System Modeling
Pedrycz, Witold
2015-01-01
In the era of advanced methodologies and practices of system modeling, we are faced with ever growing challenges of building models of complex systems that are in full rapport with reality. These challenges are multifaceted. Human centricity becomes of paramount relevance in system modeling and because of this models need to be customized and easily interpretable. More and more visibly, experimental data and knowledge of varying quality being directly acquired from experts have to be efficien...
A Model of Trusted Measurement Model
Ma Zhili; Wang Zhihao; Dai Liang; Zhu Xiaoqin
2017-01-01
A model of Trusted Measurement supporting behavior measurement based on trusted connection architecture (TCA) with three entities and three levels is proposed, and a frame to illustrate the model is given. The model synthesizes three trusted measurement dimensions including trusted identity, trusted status and trusted behavior, satisfies the essential requirements of trusted measurement, and unified the TCA with three entities and three levels.
Molecular Models: Construction of Models with Magnets
Directory of Open Access Journals (Sweden)
Kalinovčić P.
2015-07-01
Full Text Available Molecular models are indispensable tools in teaching chemistry. Beside their high price, commercially available models are generally too small for classroom demonstration. This paper suggests how to make space-filling (callote models from Styrofoam with magnetic balls as connectors and disc magnets for showing molecular polarity
Collett, David
2002-01-01
INTRODUCTION Some Examples The Scope of this Book Use of Statistical Software STATISTICAL INFERENCE FOR BINARY DATA The Binomial Distribution Inference about the Success Probability Comparison of Two Proportions Comparison of Two or More Proportions MODELS FOR BINARY AND BINOMIAL DATA Statistical Modelling Linear Models Methods of Estimation Fitting Linear Models to Binomial Data Models for Binomial Response Data The Linear Logistic Model Fitting the Linear Logistic Model to Binomial Data Goodness of Fit of a Linear Logistic Model Comparing Linear Logistic Models Linear Trend in Proportions Comparing Stimulus-Response Relationships Non-Convergence and Overfitting Some other Goodness of Fit Statistics Strategy for Model Selection Predicting a Binary Response Probability BIOASSAY AND SOME OTHER APPLICATIONS The Tolerance Distribution Estimating an Effective Dose Relative Potency Natural Response Non-Linear Logistic Regression Models Applications of the Complementary Log-Log Model MODEL CHECKING Definition of Re...
DEFF Research Database (Denmark)
Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik
1997-01-01
This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application...
DEFF Research Database (Denmark)
Hansen, Mads Fogtmann; Fagertun, Jens; Larsen, Rasmus
2011-01-01
This paper presents a fusion of the active appearance model (AAM) and the Riemannian elasticity framework which yields a non-linear shape model and a linear texture model – the active elastic appearance model (EAM). The non-linear elasticity shape model is more flexible than the usual linear...
Modelling Foundations and Applications
DEFF Research Database (Denmark)
and selected from 81 submissions. Papers on all aspects of MDE were received, including topics such as architectural modelling and product lines, code generation, domain-specic modeling, metamodeling, model analysis and verication, model management, model transformation and simulation. The breadth of topics...
Haiganoush Preisler; Alan Ager
2013-01-01
For applied mathematicians forest fire models refer mainly to a non-linear dynamic system often used to simulate spread of fire. For forest managers forest fire models may pertain to any of the three phases of fire management: prefire planning (fire risk models), fire suppression (fire behavior models), and postfire evaluation (fire effects and economic models). In...
Numerical Modelling of Streams
DEFF Research Database (Denmark)
Vestergaard, Kristian
In recent years there has been a sharp increase in the use of numerical water quality models. Numeric water quality modeling can be divided into three steps: Hydrodynamic modeling for the determination of stream flow and water levels. Modelling of transport and dispersion of a conservative dissol...... dissolved substance. Modeling of chemical and biological turnover of substances....
Willden, Jeff
2001-01-01
"Bohr's Atomic Model" is a small interactive multimedia program that introduces the viewer to a simplified model of the atom. This interactive simulation lets students build an atom using an atomic construction set. The underlying design methodology for "Bohr's Atomic Model" is model-centered instruction, which means the central model of the…
DEFF Research Database (Denmark)
Könemann, Patrick
just contain a list of strings, one for each line, whereas the structure of models is defined by their meta models. There are tools available which are able to compute the diff between two models, e.g. RSA or EMF Compare. However, their diff is not model-independent, i.e. it refers to the models...
From Numeric Models to Granular System Modeling
Directory of Open Access Journals (Sweden)
Witold Pedrycz
2015-03-01
To make this study self-contained, we briefly recall the key concepts of granular computing and demonstrate how this conceptual framework and its algorithmic fundamentals give rise to granular models. We discuss several representative formal setups used in describing and processing information granules including fuzzy sets, rough sets, and interval calculus. Key architectures of models dwell upon relationships among information granules. We demonstrate how information granularity and its optimization can be regarded as an important design asset to be exploited in system modeling and giving rise to granular models. With this regard, an important category of rule-based models along with their granular enrichments is studied in detail.
Modelling ECG signals with hidden Markov models.
Koski, A
1996-10-01
In this paper, we have studied the use of continuous probability density function hidden Markov models for the ECG signal analysis problem. Our previous work has focused on syntactic pattern recognition methods in signal processing. Hidden Markov model is basically a non-deterministic probabilistic finite state machine, which can be constructed inductively. It has been widely used in speech recognition and DNA modelling. We have found that hidden Markov models are very suitable for ECG recognition and analysis problems and that they are able to model accurately segmented ECG signals.
Modeling regional wind erosion using different model
Guo, Zhongling; Chang, Chunping; Wang, Rende; Li, Jifeng; Li, Qing
2017-04-01
Wind erosion is an important factor causing soil degradation in arid and semi-arid regions. The need to quantitatively evaluate wind induced soil erosion yields many wind erosion models. These models include Wind Erosion Equation (WEQ), Revised Wind Erosion Equation (RWEQ),Wind Erosion Predicted System (WEPS) etc. at a field scale and Wind Erosion Assessment Model (WEAM), Integrated Wind Erosion Modeling System (IWEMS), AUStralian Land Erodibility Model (AUSLEM) etc. at a regional scale. The challenge of precisely estimating wind erosion at a regional scale still remain to date. To assess regional wind erosion, WEQ, RWEQ and WEPS have been scaled up to regional versions. However, no attempt is performed to compare these models for regional wind erosion modeling. In this study, the regional versions of WEQ, RWEQ, WEPS and WEAM, IWEMS, AUSLEM will be selected to model regional wind erosion of farmlands in the Kangbao County of northern China with annual soil loss by wind erosion based on 137 Cs analysis. Remote sensing image is used to determine the size and shape of local farmlands. Weather data of 2000-2010, China Soil Survey and published soil data, crops rotations etc. are compiled to generate raster layers of inputs for selected models using ArcGIS 10.2. These models were rebuilt based on ArcGIS Model-builder Module. Spatial distribution of annual soil loss by wind erosion determined from different model will be tested using annual soil loss data by 137 Cs analysis. Performances of these models will be investigated, and restrictions of these models will be further ascertained.
Geologic Framework Model Analysis Model Report
Energy Technology Data Exchange (ETDEWEB)
R. Clayton
2000-12-19
The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M&O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and the
Earth Data Analysis Center, University of New Mexico — The model combines three modeled fire behavior parameters (rate of spread, flame length, crown fire potential) and one modeled ecological health measure (fire regime...
CSIR Research Space (South Africa)
Osburn, L
2010-01-01
Full Text Available The construction industry has turned to energy modelling in order to assist them in reducing the amount of energy consumed by buildings. However, while the energy loads of buildings can be accurately modelled, energy models often under...
Mathematical Modeling Using MATLAB
National Research Council Canada - National Science Library
Phillips, Donovan
1998-01-01
.... Mathematical Modeling Using MA MATLAB acts as a companion resource to A First Course in Mathematical Modeling with the goal of guiding the reader to a fuller understanding of the modeling process...
Borges, A. Tarciso; Gilbert, John K.
1998-01-01
Investigates the mental models that people construct about magnetic phenomena. Involves students, physics teachers, engineers, and practitioners. Proposes five models following a progression from simple description to a field model. Contains 28 references. (DDR)
Collaborative networks: Reference modeling
Camarinha-Matos, L.M.; Afsarmanesh, H.
2008-01-01
Collaborative Networks: Reference Modeling works to establish a theoretical foundation for Collaborative Networks. Particular emphasis is put on modeling multiple facets of collaborative networks and establishing a comprehensive modeling framework that captures and structures diverse perspectives of
Hiemstra, Djoerd; Lui, Ling; Özsu, M. Tamer
2017-01-01
In language modeling, n-gram models are probabilistic models of text that use some limited amount of history, or word dependencies, where n refers to the number of words that participate in the dependence relation.
Computational neurogenetic modeling
Benuskova, Lubica
2010-01-01
Computational Neurogenetic Modeling is a student text, introducing the scope and problems of a new scientific discipline - Computational Neurogenetic Modeling (CNGM). CNGM is concerned with the study and development of dynamic neuronal models for modeling brain functions with respect to genes and dynamic interactions between genes. These include neural network models and their integration with gene network models. This new area brings together knowledge from various scientific disciplines, such as computer and information science, neuroscience and cognitive science, genetics and molecular biol
1984-09-01
September 1984 MTR9S31 " J. K. Millen Computer Security C. M. Cerniglia Models * 0 Ne c - ¢- C. S• ~CONTRACT SPONSOR OUSDRE/C31 & ESO/ALEE...given in Section 5, in the form of questions and answers about security modeling. A glossary of terms used in the context of computer security is...model, so we will not be able to pursue it in this report. MODEL CHARACTERISTICS Computer security models are engineering models, giving them somewhat
DEFF Research Database (Denmark)
Andresen, Mette
2007-01-01
This paper meets the common critique of the teaching of non-authentic modelling in school mathematics. In the paper, non-authentic modelling is related to a change of view on the intentions of modelling from knowledge about applications of mathematical models to modelling for concept formation. Non......-authentic modelling is also linked with the potentials of exploration of ready-made models as a forerunner for more authentic modelling processes. The discussion includes analysis of an episode of students? work in the classroom, which serves to illustrate how concept formation may be linked to explorations of a non...
DEFF Research Database (Denmark)
Rask, Morten
insight from the literature about business models, international product policy, international entry modes and globalization into a conceptual model of relevant design elements of global business models, enabling global business model innovation to deal with differences in a downstream perspective...... regarding the customer interface and in an upstream perspective regarding the supply infrastructure. The paper offers a coherent conceptual dynamic meta-model of global business model innovation. Students, scholars and managers within the field of international business can use this conceptualization...... to understand, to study, and to create global business model innovation. Managerial and research implications draw on the developed ideal type of global business model innovation....
Federal Laboratory Consortium — The Environmental Modeling Center provides the computational tools to perform geostatistical analysis, to model ground water and atmospheric releases for comparison...
Overuse Injury Assessment Model
National Research Council Canada - National Science Library
Stuhmiller, James H; Shen, Weixin; Sih, Bryant
2005-01-01
.... Previously, we developed a preliminary model that predicted the stress fracture rate and used biomechanical modeling, nonlinear optimization for muscle force, and bone structural analysis to estimate...
National Aeronautics and Space Administration — CLAIRE MONTELEONI*, GAVIN SCHMIDT, AND SHAILESH SAROHA* Climate models are complex mathematical models designed by meteorologists, geophysicists, and climate...
DEFF Research Database (Denmark)
Knudsen, Torben
2011-01-01
model structure suggested by University of Lund the WP4 leader. This particular model structure has the advantages that it fits better into the control design frame work used by WP3-4 compared to the model structures previously developed in WP2. The different model structures are first summarised....... Then issues dealing with optimal experimental design is considered. Finally the parameters are estimated in the chosen static and dynamic models and a validation is performed. Two of the static models, one of them the additive model, explains the data well. In case of dynamic models the suggested additive...... model turns out not to be useful for prediction of the flow. Moreover, standard Box Jenkins model structures and multiple output auto regressive models proves to be superior as they can give useful predictions of the flow....
DEFF Research Database (Denmark)
Cameron, Ian T.; Gani, Rafiqul
This book covers the area of product and process modelling via a case study approach. It addresses a wide range of modelling applications with emphasis on modelling methodology and the subsequent in-depth analysis of mathematical models to gain insight via structural aspects of the models....... These approaches are put into the context of life cycle modelling, where multiscale and multiform modelling is increasingly prevalent in the 21st century. The book commences with a discussion of modern product and process modelling theory and practice followed by a series of case studies drawn from a variety...... of process industries. The book builds on the extensive modelling experience of the authors, who have developed models for both research and industrial purposes. It complements existing books by the authors in the modelling area. Those areas include the traditional petroleum and petrochemical industries...
ROCK PROPERTIES MODEL ANALYSIS MODEL REPORT
Energy Technology Data Exchange (ETDEWEB)
Clinton Lum
2002-02-04
The purpose of this Analysis and Model Report (AMR) is to document Rock Properties Model (RPM) 3.1 with regard to input data, model methods, assumptions, uncertainties and limitations of model results, and qualification status of the model. The report also documents the differences between the current and previous versions and validation of the model. The rock properties models are intended principally for use as input to numerical physical-process modeling, such as of ground-water flow and/or radionuclide transport. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. This work was conducted in accordance with the following planning documents: WA-0344, ''3-D Rock Properties Modeling for FY 1998'' (SNL 1997, WA-0358), ''3-D Rock Properties Modeling for FY 1999'' (SNL 1999), and the technical development plan, Rock Properties Model Version 3.1, (CRWMS M&O 1999c). The Interim Change Notice (ICNs), ICN 02 and ICN 03, of this AMR were prepared as part of activities being conducted under the Technical Work Plan, TWP-NBS-GS-000003, ''Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01'' (CRWMS M&O 2000b). The purpose of ICN 03 is to record changes in data input status due to data qualification and verification activities. These work plans describe the scope, objectives, tasks, methodology, and implementing procedures for model construction. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The work scope for this activity consists of the following: (1) Conversion of the input data (laboratory measured porosity data, x-ray diffraction mineralogy, petrophysical calculations of bound water, and petrophysical calculations of porosity) for each borehole into stratigraphic coordinates; (2) Re-sampling and merging of data sets; (3
A Model of Trusted Measurement Model
Directory of Open Access Journals (Sweden)
Ma Zhili
2017-01-01
Full Text Available A model of Trusted Measurement supporting behavior measurement based on trusted connection architecture (TCA with three entities and three levels is proposed, and a frame to illustrate the model is given. The model synthesizes three trusted measurement dimensions including trusted identity, trusted status and trusted behavior, satisfies the essential requirements of trusted measurement, and unified the TCA with three entities and three levels.
Integrity modelling of tropospheric delay models
Rózsa, Szabolcs; Bastiaan Ober, Pieter; Mile, Máté; Ambrus, Bence; Juni, Ildikó
2017-04-01
The effect of the neutral atmosphere on signal propagation is routinely estimated by various tropospheric delay models in satellite navigation. Although numerous studies can be found in the literature investigating the accuracy of these models, for safety-of-life applications it is crucial to study and model the worst case performance of these models using very low recurrence frequencies. The main objective of the INTegrity of TROpospheric models (INTRO) project funded by the ESA PECS programme is to establish a model (or models) of the residual error of existing tropospheric delay models for safety-of-life applications. Such models are required to overbound rare tropospheric delays and should thus include the tails of the error distributions. Their use should lead to safe error bounds on the user position and should allow computation of protection levels for the horizontal and vertical position errors. The current tropospheric model from the RTCA SBAS Minimal Operational Standards has an associated residual error that equals 0.12 meters in the vertical direction. This value is derived by simply extrapolating the observed distribution of the residuals into the tail (where no data is present) and then taking the point where the cumulative distribution has an exceedance level would be 10-7.While the resulting standard deviation is much higher than the estimated standard variance that best fits the data (0.05 meters), it surely is conservative for most applications. In the context of the INTRO project some widely used and newly developed tropospheric delay models (e.g. RTCA MOPS, ESA GALTROPO and GPT2W) were tested using 16 years of daily ERA-INTERIM Reanalysis numerical weather model data and the raytracing technique. The results showed that the performance of some of the widely applied models have a clear seasonal dependency and it is also affected by a geographical position. In order to provide a more realistic, but still conservative estimation of the residual
Objective Bayes model selection in probit models.
Leon-Novelo, Luis; Moreno, Elías; Casella, George
2012-02-20
We describe a new variable selection procedure for categorical responses where the candidate models are all probit regression models. The procedure uses objective intrinsic priors for the model parameters, which do not depend on tuning parameters, and ranks the models for the different subsets of covariates according to their model posterior probabilities. When the number of covariates is moderate or large, the number of potential models can be very large, and for those cases, we derive a new stochastic search algorithm that explores the potential sets of models driven by their model posterior probabilities. The algorithm allows the user to control the dimension of the candidate models and thus can handle situations when the number of covariates exceed the number of observations. We assess, through simulations, the performance of the procedure and apply the variable selector to a gene expression data set, where the response is whether a patient exhibits pneumonia. Software needed to run the procedures is available in the R package varselectIP. Copyright © 2011 John Wiley & Sons, Ltd.
New 3D model for dynamics modeling
Perez, Alain
1994-05-01
The wrist articulation represents one of the most complex mechanical systems of the human body. It is composed of eight bones rolling and sliding along their surface and along the faces of the five metacarpals of the hand and the two bones of the arm. The wrist dynamics are however fundamental for the hand movement, but it is so complex that it still remains incompletely explored. This work is a part of a new concept of computer-assisted surgery, which consists in developing computer models to perfect surgery acts by predicting their consequences. The modeling of the wrist dynamics are based first on the static model of its bones in three dimensions. This 3D model must optimise the collision detection procedure which is the necessary step to estimate the physical contact constraints. As many other possible computer vision models do not fit with enough precision to this problem, a new 3D model has been developed thanks to the median axis of the digital distance map of the bones reconstructed volume. The collision detection procedure is then simplified for contacts are detected between spheres. The experiment of this original 3D dynamic model products realistic computer animation images of solids in contact. It is now necessary to detect ligaments on digital medical images and to model them in order to complete a wrist model.
Better models are more effectively connected models
Nunes, João Pedro; Bielders, Charles; Darboux, Frederic; Fiener, Peter; Finger, David; Turnbull-Lloyd, Laura; Wainwright, John
2016-04-01
The concept of hydrologic and geomorphologic connectivity describes the processes and pathways which link sources (e.g. rainfall, snow and ice melt, springs, eroded areas and barren lands) to accumulation areas (e.g. foot slopes, streams, aquifers, reservoirs), and the spatial variations thereof. There are many examples of hydrological and sediment connectivity on a watershed scale; in consequence, a process-based understanding of connectivity is crucial to help managers understand their systems and adopt adequate measures for flood prevention, pollution mitigation and soil protection, among others. Modelling is often used as a tool to understand and predict fluxes within a catchment by complementing observations with model results. Catchment models should therefore be able to reproduce the linkages, and thus the connectivity of water and sediment fluxes within the systems under simulation. In modelling, a high level of spatial and temporal detail is desirable to ensure taking into account a maximum number of components, which then enables connectivity to emerge from the simulated structures and functions. However, computational constraints and, in many cases, lack of data prevent the representation of all relevant processes and spatial/temporal variability in most models. In most cases, therefore, the level of detail selected for modelling is too coarse to represent the system in a way in which connectivity can emerge; a problem which can be circumvented by representing fine-scale structures and processes within coarser scale models using a variety of approaches. This poster focuses on the results of ongoing discussions on modelling connectivity held during several workshops within COST Action Connecteur. It assesses the current state of the art of incorporating the concept of connectivity in hydrological and sediment models, as well as the attitudes of modellers towards this issue. The discussion will focus on the different approaches through which connectivity
Energy Technology Data Exchange (ETDEWEB)
D. W. Wu
2003-07-16
The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).
Energy Technology Data Exchange (ETDEWEB)
M. A. Wasiolek
2003-10-27
The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).
Rahmani, Fouad Lazhar
2010-11-01
The aim of this paper is to present mathematical modelling of the spread of infection in the context of the transmission of the human immunodeficiency virus (HIV) and the acquired immune deficiency syndrome (AIDS). These models are based in part on the models suggested in the field of th AIDS mathematical modelling as reported by ISHAM [6].
Comparing Active Vision Models
Croon, G.C.H.E. de; Sprinkhuizen-Kuyper, I.G.; Postma, E.O.
2009-01-01
Active vision models can simplify visual tasks, provided that they can select sensible actions given incoming sensory inputs. Many active vision models have been proposed, but a comparative evaluation of these models is lacking. We present a comparison of active vision models from two different
DEFF Research Database (Denmark)
Silvennoinen, Annastiina; Teräsvirta, Timo
This article contains a review of multivariate GARCH models. Most common GARCH models are presented and their properties considered. This also includes nonparametric and semiparametric models. Existing specification and misspecification tests are discussed. Finally, there is an empirical example...... in which several multivariate GARCH models are fitted to the same data set and the results compared....
R. Pietersz (Raoul); M. van Regenmortel
2005-01-01
textabstractCurrently, there are two market models for valuation and risk management of interest rate derivatives, the LIBOR and swap market models. In this paper, we introduce arbitrage-free constant maturity swap (CMS) market models and generic market models featuring forward rates that span
Models of Counselling Centres.
Calgary Univ. (Alberta).
University counseling centers usually follow one of a variety of themes or "models," although not in pure form. Perhaps the oldest is the vocational counseling model, which concentrates on helping students find suitable careers. In the psychotherapy model, most student concerns are seen for their personal content. Another model, student affairs…
Yeates, Devin Rodney
2011-01-01
The goal of this dissertation is to enable better predictive models by engaging raw experimental data through the Instrumental Model. The Instrumental Model captures the protocols and procedures of experimental data analysis. The approach is formalized by encoding the Instrumental Model in an XML record. Decoupling the raw experimental data from…
D.J.N. van Eijck (Jan)
2004-01-01
textabstractThis paper introduces DEMO, a Dynamic Epistemic Modelling tool. DEMO llows modelling epistemic updates, graphical display of update results, graphical display of action models, formula evaluation in epistemic models, translation of dynamic epistemic formulas to PDL formulas, and so on.
System equivalent model mixing
Klaassen, Steven W.B.; van der Seijs, M.V.; de Klerk, D.
2017-01-01
This paper introduces SEMM: a method based on Frequency Based Substructuring (FBS) techniques that enables the construction of hybrid dynamic models. With System Equivalent Model Mixing (SEMM) frequency based models, either of numerical or experimental nature, can be mixed to form a hybrid model.
Comparing active vision models
Croon, G.C.H.E. de; Sprinkhuizen-Kuyper, I.G.; Postma, E.O.
2009-01-01
Active vision models can simplify visual tasks, provided that they can select sensible actions given incoming sensory inputs. Many active vision models have been proposed, but a comparative evaluation of these models is lacking. We present a comparison of active vision models from two different
Andrist, R.B.; Haworth, G.McC.
2005-01-01
A reference model of Fallible Endgame Play has been implemented and exercised with the chess-engine WILHELM. Past experiments have demonstrated the value of the model and the robustness of decisions based on it: experiments agree well with a Markov Model theory. Here, the reference model is exercised on the well-known endgame KBBKN.
DEFF Research Database (Denmark)
Ayres, Phil
2012-01-01
This essay discusses models. It examines what models are, the roles models perform and suggests various intentions that underlie their construction and use. It discusses how models act as a conversational partner, and how they support various forms of conversation within the conversational activity...... of design. Three distinctions are drawn through which to develop this discussion of models in an architectural context. An examination of these distinctions serves to nuance particular characteristics and roles of models, the modelling activity itself and those engaged in it....
DEFF Research Database (Denmark)
Gernaey, Krist; Sin, Gürkan
2008-01-01
The state-of-the-art level reached in modeling wastewater treatment plants (WWTPs) is reported. For suspended growth systems, WWTP models have evolved from simple description of biological removal of organic carbon and nitrogen in aeration tanks (ASM1 in 1987) to more advanced levels including...... the practice of WWTP modeling by linking the wastewater treatment line with the sludge handling line in one modeling platform. Application of WWTP models is currently rather time consuming and thus expensive due to the high model complexity, and requires a great deal of process knowledge and modeling expertise...
DEFF Research Database (Denmark)
Gernaey, Krist; Sin, Gürkan
2011-01-01
The state-of-the-art level reached in modeling wastewater treatment plants (WWTPs) is reported. For suspended growth systems, WWTP models have evolved from simple description of biological removal of organic carbon and nitrogen in aeration tanks (ASM1 in 1987) to more advanced levels including...... of WWTP modeling by linking the wastewater treatment line with the sludge handling line in one modeling platform. Application of WWTP models is currently rather time consuming and thus expensive due to the high model complexity, and requires a great deal of process knowledge and modeling expertise...
Morgan, Byron JT; Tanner, Martin Abba; Carlin, Bradley P
2008-01-01
Introduction and Examples Introduction Examples of data sets Basic Model Fitting Introduction Maximum-likelihood estimation for a geometric model Maximum-likelihood for the beta-geometric model Modelling polyspermy Which model? What is a model for? Mechanistic models Function Optimisation Introduction MATLAB: graphs and finite differences Deterministic search methods Stochastic search methods Accuracy and a hybrid approach Basic Likelihood ToolsIntroduction Estimating standard errors and correlations Looking at surfaces: profile log-likelihoods Confidence regions from profiles Hypothesis testing in model selectionScore and Wald tests Classical goodness of fit Model selection biasGeneral Principles Introduction Parameterisation Parameter redundancy Boundary estimates Regression and influence The EM algorithm Alternative methods of model fitting Non-regular problemsSimulation Techniques Introduction Simulating random variables Integral estimation Verification Monte Carlo inference Estimating sampling distributi...
DEFF Research Database (Denmark)
Justesen, Lise; Overgaard, Svend Skafte
2017-01-01
This article presents an analytical model that aims to conceptualize how meal experiences are framed when taking into account a dynamic understanding of hospitality: the meal model is named The Hospitable Meal Model. The idea behind The Hospitable Meal Model is to present a conceptual model...... that can serve as a frame for developing hospitable meal competencies among professionals working within the area of institutional foodservices as well as a conceptual model for analysing meal experiences. The Hospitable Meal Model transcends and transforms existing meal models by presenting a more open......-ended approach towards meal experiences. The underlying purpose of The Hospitable Meal Model is to provide the basis for creating value for the individuals involved in institutional meal services. The Hospitable Meal Model was developed on the basis of an empirical study on hospital meal experiences explored...
Takahashi, Takehiro; Schibuya, Noboru
The EMC simulation is now widely used in design stage of electronic equipment to reduce electromagnetic noise. As the calculated electromagnetic behaviors of the EMC simulator depends on the inputted EMC model of the equipment, the modeling technique is important to obtain effective results. In this paper, simple outline of the EMC simulator and EMC model are described. Some modeling techniques of EMC simulation are also described with an example of the EMC model which is shield box with aperture.
DEFF Research Database (Denmark)
Langseth, Helge; Nielsen, Thomas Dyhre
2005-01-01
parametric family ofdistributions. In this paper we propose a new set of models forclassification in continuous domains, termed latent classificationmodels. The latent classification model can roughly be seen ascombining the \\NB model with a mixture of factor analyzers,thereby relaxing the assumptions...... classification model, and wedemonstrate empirically that the accuracy of the proposed model issignificantly higher than the accuracy of other probabilisticclassifiers....
Dynamical Dirichlet Mixture Model
Chen, Le; Barber, David; Odobez, Jean-Marc
2007-01-01
In this report, we propose a statistical model to deal with the discrete-distribution data varying over time. The proposed model -- HMM+DM -- extends the Dirichlet mixture model to the dynamic case: Hidden Markov Model with Dirichlet mixture output. Both the inference and parameter estimation procedures are proposed. Experiments on the generated data verify the proposed algorithms. Finally, we discuss the potential applications of the current model.
Phenomenology of inflationary models
Olyaei, Abbas
2018-01-01
There are many inflationary models compatible with observational data. One can investigate inflationary models by looking at their general features, which are common in most of the models. Here we have investigated some of the single-field models without considering their origin in order to find the phenomenology of them. We have shown how to adjust the simple harmonic oscillator model in order to be in good agreement with observational data.
DEFF Research Database (Denmark)
Høskuldsson, Agnar
1996-01-01
Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four...... the basic problems in determining the dimension of linear models. Then each of the eight measures are treated. The results are illustrated by examples....
Business Models and Business Model Innovation
DEFF Research Database (Denmark)
Foss, Nicolai J.; Saebi, Tina
2017-01-01
While research on business models and business model innovation continue to exhibit growth, the field is still, even after more than two decades of research, characterized by a striking lack of cumulative theorizing and an opportunistic borrowing of more or less related ideas from neighbouring...
Modeling survival data extending the cox model
Therneau, Terry M
2000-01-01
Extending the Cox Model is aimed at researchers, practitioners, and graduate students who have some exposure to traditional methods of survival analysis The emphasis is on semiparametric methods based on the proportional hazards model The inclusion of examples with SAS and S-PLUS code will make the book accessible to most working statisticians
Pavement Aging Model by Response Surface Modeling
Directory of Open Access Journals (Sweden)
Manzano-Ramírez A.
2011-10-01
Full Text Available In this work, surface course aging was modeled by Response Surface Methodology (RSM. The Marshall specimens were placed in a conventional oven for time and temperature conditions established on the basis of the environment factors of the region where the surface course is constructed by AC-20 from the Ing. Antonio M. Amor refinery. Volatilized material (VM, load resistance increment (ΔL and flow resistance increment (ΔF models were developed by the RSM. Cylindrical specimens with real aging were extracted from the surface course pilot to evaluate the error of the models. The VM model was adequate, in contrast (ΔL and (ΔF models were almost adequate with an error of 20 %, that was associated with the other environmental factors, which were not considered at the beginning of the research.
Trapped Radiation Model Uncertainties: Model-Data and Model-Model Comparisons
Armstrong, T. W.; Colborn, B. L.
2000-01-01
The standard AP8 and AE8 models for predicting trapped proton and electron environments have been compared with several sets of flight data to evaluate model uncertainties. Model comparisons are made with flux and dose measurements made on various U.S. low-Earth orbit satellites (APEX, CRRES, DMSP, LDEF, NOAA) and Space Shuttle flights, on Russian satellites (Photon-8, Cosmos-1887, Cosmos-2044), and on the Russian Mir Space Station. This report gives the details of the model-data comparisons-summary results in terms of empirical model uncertainty factors that can be applied for spacecraft design applications are given in a combination report. The results of model-model comparisons are also presented from standard AP8 and AE8 model predictions compared with the European Space Agency versions of AP8 and AE8 and with Russian-trapped radiation models.
DEFF Research Database (Denmark)
Hansen, Peter Reinhard; Lunde, Asger; Nason, James M.
acknowledges the limitations of the data, such that uninformative data yields a MCS with many models, whereas informative data yields a MCS with only a few models. The MCS procedure does not assume that a particular model is the true model, in fact theMCS procedure can be used to comparemore general objects......The paper introduces the model confidence set (MCS) and applies it to the selection of models. A MCS is a set of models that is constructed such that it will contain the best model with a given level of confidence. The MCS is in this sense analogous to a confidence interval for a parameter. The MCS......, beyond the comparison of models. We apply the MCS procedure to two empirical problems. First, we revisit the inflation forecasting problem posed by Stock and Watson (1999), and compute the MCS for their set of inflation forecasts. Second, we compare a number of Taylor rule regressions and determine...
Practical Marginalized Multilevel Models
Griswold, Michael E.; Swihart, Bruce J.; Caffo, Brian S.; Zeger, Scott L.
2013-01-01
Clustered data analysis is characterized by the need to describe both systematic variation in a mean model and cluster-dependent random variation in an association model. Marginalized multilevel models embrace the robustness and interpretations of a marginal mean model, while retaining the likelihood inference capabilities and flexible dependence structures of a conditional association model. Although there has been increasing recognition of the attractiveness of marginalized multilevel models, there has been a gap in their practical application arising from a lack of readily available estimation procedures. We extend the marginalized multilevel model to allow for nonlinear functions in both the mean and association aspects. We then formulate marginal models through conditional specifications to facilitate estimation with mixed model computational solutions already in place. We illustrate the MMM and approximate MMM approaches on a cerebrovascular deficiency crossover trial using SAS and an epidemiological study on race and visual impairment using R. Datasets, SAS and R code are included as supplemental materials. PMID:24357884
DEFF Research Database (Denmark)
Cameron, Ian T.; Gani, Rafiqul
to biotechnology applications, food, polymer and human health application areas. The book highlights to important nature of modern product and process modelling in the decision making processes across the life cycle. As such it provides an important resource for students, researchers and industrial practitioners.......This book covers the area of product and process modelling via a case study approach. It addresses a wide range of modelling applications with emphasis on modelling methodology and the subsequent in-depth analysis of mathematical models to gain insight via structural aspects of the models....... These approaches are put into the context of life cycle modelling, where multiscale and multiform modelling is increasingly prevalent in the 21st century. The book commences with a discussion of modern product and process modelling theory and practice followed by a series of case studies drawn from a variety...
DEFF Research Database (Denmark)
Cameron, Ian T.; Gani, Rafiqul
This book covers the area of product and process modelling via a case study approach. It addresses a wide range of modelling applications with emphasis on modelling methodology and the subsequent in-depth analysis of mathematical models to gain insight via structural aspects of the models...... of process industries. The book builds on the extensive modelling experience of the authors, who have developed models for both research and industrial purposes. It complements existing books by the authors in the modelling area. Those areas include the traditional petroleum and petrochemical industries...... to biotechnology applications, food, polymer and human health application areas. The book highlights to important nature of modern product and process modelling in the decision making processes across the life cycle. As such it provides an important resource for students, researchers and industrial practitioners....
Model Validation Status Review
Energy Technology Data Exchange (ETDEWEB)
E.L. Hardin
2001-11-28
The primary objective for the Model Validation Status Review was to perform a one-time evaluation of model validation associated with the analysis/model reports (AMRs) containing model input to total-system performance assessment (TSPA) for the Yucca Mountain site recommendation (SR). This review was performed in response to Corrective Action Request BSC-01-C-01 (Clark 2001, Krisha 2001) pursuant to Quality Assurance review findings of an adverse trend in model validation deficiency. The review findings in this report provide the following information which defines the extent of model validation deficiency and the corrective action needed: (1) AMRs that contain or support models are identified, and conversely, for each model the supporting documentation is identified. (2) The use for each model is determined based on whether the output is used directly for TSPA-SR, or for screening (exclusion) of features, events, and processes (FEPs), and the nature of the model output. (3) Two approaches are used to evaluate the extent to which the validation for each model is compliant with AP-3.10Q (Analyses and Models). The approaches differ in regard to whether model validation is achieved within individual AMRs as originally intended, or whether model validation could be readily achieved by incorporating information from other sources. (4) Recommendations are presented for changes to the AMRs, and additional model development activities or data collection, that will remedy model validation review findings, in support of licensing activities. The Model Validation Status Review emphasized those AMRs that support TSPA-SR (CRWMS M&O 2000bl and 2000bm). A series of workshops and teleconferences was held to discuss and integrate the review findings. The review encompassed 125 AMRs (Table 1) plus certain other supporting documents and data needed to assess model validity. The AMRs were grouped in 21 model areas representing the modeling of processes affecting the natural and
Modeling volatility using state space models.
Timmer, J; Weigend, A S
1997-08-01
In time series problems, noise can be divided into two categories: dynamic noise which drives the process, and observational noise which is added in the measurement process, but does not influence future values of the system. In this framework, we show that empirical volatilities (the squared relative returns of prices) exhibit a significant amount of observational noise. To model and predict their time evolution adequately, we estimate state space models that explicitly include observational noise. We obtain relaxation times for shocks in the logarithm of volatility ranging from three weeks (for foreign exchange) to three to five months (for stock indices). In most cases, a two-dimensional hidden state is required to yield residuals that are consistent with white noise. We compare these results with ordinary autoregressive models (without a hidden state) and find that autoregressive models underestimate the relaxation times by about two orders of magnitude since they do not distinguish between observational and dynamic noise. This new interpretation of the dynamics of volatility in terms of relaxators in a state space model carries over to stochastic volatility models and to GARCH models, and is useful for several problems in finance, including risk management and the pricing of derivative securities. Data sets used: Olsen & Associates high frequency DEM/USD foreign exchange rates (8 years). Nikkei 225 index (40 years). Dow Jones Industrial Average (25 years).
Model checking of healthcare domain models.
Baksi, Dibyendu
2009-12-01
This paper shows the application of a type of formal software verification technique known as lightweight model checking to a domain model in healthcare informatics in general and public health surveillance systems in particular. One of the most complex use cases of such a system is checked using assertions to verify one important system property. This use case is one of the major justifications for the complexity of the domain model. Alloy Analyzer verification tool is utilized for this purpose. Such verification work is very effective in either uncovering design flaws or in providing guarantees on certain desirable system properties in the earlier phases of the development lifecycle of any critical project.
Modeling Guru: Knowledge Base for NASA Modelers
Seablom, M. S.; Wojcik, G. S.; van Aartsen, B. H.
2009-05-01
Modeling Guru is an on-line knowledge-sharing resource for anyone involved with or interested in NASA's scientific models or High End Computing (HEC) systems. Developed and maintained by the NASA's Software Integration and Visualization Office (SIVO) and the NASA Center for Computational Sciences (NCCS), Modeling Guru's combined forums and knowledge base for research and collaboration is becoming a repository for the accumulated expertise of NASA's scientific modeling and HEC communities. All NASA modelers and associates are encouraged to participate and provide knowledge about the models and systems so that other users may benefit from their experience. Modeling Guru is divided into a hierarchy of communities, each with its own set forums and knowledge base documents. Current modeling communities include those for space science, land and atmospheric dynamics, atmospheric chemistry, and oceanography. In addition, there are communities focused on NCCS systems, HEC tools and libraries, and programming and scripting languages. Anyone may view most of the content on Modeling Guru (available at http://modelingguru.nasa.gov/), but you must log in to post messages and subscribe to community postings. The site offers a full range of "Web 2.0" features, including discussion forums, "wiki" document generation, document uploading, RSS feeds, search tools, blogs, email notification, and "breadcrumb" links. A discussion (a.k.a. forum "thread") is used to post comments, solicit feedback, or ask questions. If marked as a question, SIVO will monitor the thread, and normally respond within a day. Discussions can include embedded images, tables, and formatting through the use of the Rich Text Editor. Also, the user can add "Tags" to their thread to facilitate later searches. The "knowledge base" is comprised of documents that are used to capture and share expertise with others. The default "wiki" document lets users edit within the browser so others can easily collaborate on the
Empirical Model Building Data, Models, and Reality
Thompson, James R
2011-01-01
Praise for the First Edition "This...novel and highly stimulating book, which emphasizes solving real problems...should be widely read. It will have a positive and lasting effect on the teaching of modeling and statistics in general." - Short Book Reviews This new edition features developments and real-world examples that showcase essential empirical modeling techniques Successful empirical model building is founded on the relationship between data and approximate representations of the real systems that generated that data. As a result, it is essential for researchers who construct these m
DEFF Research Database (Denmark)
Branlard, Emmanuel Simon Pierre
2017-01-01
Different models of wake expansion are presented in this chapter: the 1D momentum theory model, the cylinder analog model and Theodorsen’s model. Far wake models such as the ones from Frandsen or Rathmann or only briefly mentioned. The different models are compared to each other. Results from thi...... this chapter are used in Chap. 16 to link near-wake and far-wake parameters and in Chap. 20 to study the influence of expansion on tip-losses....
Energy Technology Data Exchange (ETDEWEB)
Reiter, E.R.
1980-01-01
A highly sophisticated and accurate approach is described to compute on an hourly or daily basis the energy consumption for space heating by individual buildings, urban sectors, and whole cities. The need for models and specifically weather-sensitive models, composite models, and space-heating models are discussed. Development of the Colorado State University Model, based on heat-transfer equations and on a heuristic, adaptive, self-organizing computation learning approach, is described. Results of modeling energy consumption by the city of Minneapolis and Cheyenne are given. Some data on energy consumption in individual buildings are included.
Peabody, Hume L.
2017-01-01
This presentation is meant to be an overview of the model building process It is based on typical techniques (Monte Carlo Ray Tracing for radiation exchange, Lumped Parameter, Finite Difference for thermal solution) used by the aerospace industry This is not intended to be a "How to Use ThermalDesktop" course. It is intended to be a "How to Build Thermal Models" course and the techniques will be demonstrated using the capabilities of ThermalDesktop (TD). Other codes may or may not have similar capabilities. The General Model Building Process can be broken into four top level steps: 1. Build Model; 2. Check Model; 3. Execute Model; 4. Verify Results.
Program management model study
Connelly, J. J.; Russell, J. E.; Seline, J. R.; Sumner, N. R., Jr.
1972-01-01
Two models, a system performance model and a program assessment model, have been developed to assist NASA management in the evaluation of development alternatives for the Earth Observations Program. Two computer models were developed and demonstrated on the Goddard Space Flight Center Computer Facility. Procedures have been outlined to guide the user of the models through specific evaluation processes, and the preparation of inputs describing earth observation needs and earth observation technology. These models are intended to assist NASA in increasing the effectiveness of the overall Earth Observation Program by providing a broader view of system and program development alternatives.
Microsoft tabular modeling cookbook
Braak, Paul te
2013-01-01
This book follows a cookbook style with recipes explaining the steps for developing analytic data using Business Intelligence Semantic Models.This book is designed for developers who wish to develop powerful and dynamic models for users as well as those who are responsible for the administration of models in corporate environments. It is also targeted at analysts and users of Excel who wish to advance their knowledge of Excel through the development of tabular models or who wish to analyze data through tabular modeling techniques. We assume no prior knowledge of tabular modeling
Marstal, Kasper; Klein, Stefan
2017-02-01
We present the Active Registration Model (ARM) that couples medical image registration with regularization using a statistical model of intensity. Inspired by Active Appearance Models (AAMs), the statistical model is embedded in the registration procedure as a regularization term that penalize differences between a target image and a synthesized model reconstruction of that image. We demonstrate that the method generalizes AAMs to 3D images, many different transformation models, and many different gradient descent optimization methods. The method is validated on magnetic resonance images of human brains.
Energy Technology Data Exchange (ETDEWEB)
Thatcher, R.M.
1984-05-01
The Surface-To-Air Missile (SAM) Electro-Magnetic-Pulse (EMP) (SEMP) model simulates the illumination of an entire SAM brigade with an EMP weapon. It computes probability distributions of SAM brigade performance levels after an EMP attack has occurred. Brigade performance is determined by the combination of components that survive the EMP. Accordingly, the SEMP model is separated into the component failure model and the condition model. The component failure model computes the failure probability of each component in the brigade from data supplied by two input data files. The condition model converts component failure probabilities into brigade performance in the form of missile availability probability tables.
Geller, Michael; Telem, Ofri
2015-05-15
We present the first realization of a "twin Higgs" model as a holographic composite Higgs model. Uniquely among composite Higgs models, the Higgs potential is protected by a new standard model (SM) singlet elementary "mirror" sector at the sigma model scale f and not by the composite states at m_{KK}, naturally allowing for m_{KK} beyond the LHC reach. As a result, naturalness in our model cannot be constrained by the LHC, but may be probed by precision Higgs measurements at future lepton colliders, and by direct searches for Kaluza-Klein excitations at a 100 TeV collider.
Energy Technology Data Exchange (ETDEWEB)
D.W. Wu; A.J. Smith
2004-11-08
The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), TSPA-LA. The ERMYN provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs) (Section 6.2), the reference biosphere (Section 6.1.1), the human receptor (Section 6.1.2), and approximations (Sections 6.3.1.4 and 6.3.2.4); (3) Building a mathematical model using the biosphere conceptual model (Section 6.3) and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); (8) Validating the ERMYN by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).
Modelling of Innovation Diffusion
Directory of Open Access Journals (Sweden)
Arkadiusz Kijek
2010-01-01
Full Text Available Since the publication of the Bass model in 1969, research on the modelling of the diffusion of innovation resulted in a vast body of scientific literature consisting of articles, books, and studies of real-world applications of this model. The main objective of the diffusion model is to describe a pattern of spread of innovation among potential adopters in terms of a mathematical function of time. This paper assesses the state-of-the-art in mathematical models of innovation diffusion and procedures for estimating their parameters. Moreover, theoretical issues related to the models presented are supplemented with empirical research. The purpose of the research is to explore the extent to which the diffusion of broadband Internet users in 29 OECD countries can be adequately described by three diffusion models, i.e. the Bass model, logistic model and dynamic model. The results of this research are ambiguous and do not indicate which model best describes the diffusion pattern of broadband Internet users but in terms of the results presented, in most cases the dynamic model is inappropriate for describing the diffusion pattern. Issues related to the further development of innovation diffusion models are discussed and some recommendations are given. (original abstract
Model Checking CSL for Markov Population Models
Directory of Open Access Journals (Sweden)
David Spieler
2014-06-01
Full Text Available Markov population models (MPMs are a widely used modelling formalism in the area of computational biology and related areas. The semantics of a MPM is an infinite-state continuous-time Markov chain. In this paper, we use the established continuous stochastic logic (CSL to express properties of Markov population models. This allows us to express important measures of biological systems, such as probabilistic reachability, survivability, oscillations, switching times between attractor regions, and various others. Because of the infinite state space, available analysis techniques only apply to a very restricted subset of CSL properties. We present a full algorithm for model checking CSL for MPMs, and provide experimental evidence showing that our method is effective.
Traffic & safety statewide model and GIS modeling.
2012-07-01
Several steps have been taken over the past two years to advance the Utah Department of Transportation (UDOT) safety initiative. Previous research projects began the development of a hierarchical Bayesian model to analyze crashes on Utah roadways. De...
Nonlinear Modeling by Assembling Piecewise Linear Models
Yao, Weigang; Liou, Meng-Sing
2013-01-01
To preserve nonlinearity of a full order system over a parameters range of interest, we propose a simple modeling approach by assembling a set of piecewise local solutions, including the first-order Taylor series terms expanded about some sampling states. The work by Rewienski and White inspired our use of piecewise linear local solutions. The assembly of these local approximations is accomplished by assigning nonlinear weights, through radial basis functions in this study. The efficacy of the proposed procedure is validated for a two-dimensional airfoil moving at different Mach numbers and pitching motions, under which the flow exhibits prominent nonlinear behaviors. All results confirm that our nonlinear model is accurate and stable for predicting not only aerodynamic forces but also detailed flowfields. Moreover, the model is robustness-accurate for inputs considerably different from the base trajectory in form and magnitude. This modeling preserves nonlinearity of the problems considered in a rather simple and accurate manner.
Modelling freeway networks by hybrid stochastic models
Boel, R.; Mihaylova, L.
2004-01-01
Traffic flow on freeways is a nonlinear, many-particle phenomenon, with complex interactions between the vehicles. This paper presents a stochastic hybrid model of freeway traffic at a time scale and at a level of detail suitable for on-line flow estimation, for routing and ramp metering control. The model describes the evolution of continuous and discrete state variables. The freeway is considered as a network of components, each component representing a different section of the network. The...
Laboratory of Biological Modeling
Federal Laboratory Consortium — The Laboratory of Biological Modeling is defined by both its methodologies and its areas of application. We use mathematical modeling in many forms and apply it to a...
Modeling EERE deployment programs
Energy Technology Data Exchange (ETDEWEB)
Cort, K. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hostick, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Belzer, D. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Livingston, O. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2007-11-01
The purpose of the project was to identify and characterize the modeling of deployment programs within the EERE Technology Development (TD) programs, address possible improvements to the modeling process, and note gaps in knowledge for future research.
National Oceanic and Atmospheric Administration, Department of Commerce — The World Magnetic Model is the standard model used by the U.S. Department of Defense, the U.K. Ministry of Defence, the North Atlantic Treaty Organization (NATO)...
National Research Council Canada - National Science Library
Feiler, Peter
2007-01-01
.... The Society of Automotive Engineers (SAE) Architecture Analysis & Design Language (AADL) is an industry-standard, architecture-modeling notation specifically designed to support a component- based approach to modeling embedded systems...
DEFF Research Database (Denmark)
Højsgaard, Søren; Edwards, David; Lauritzen, Steffen L.
Graphical models in their modern form have been around since the late 1970s and appear today in many areas of the sciences. Along with the ongoing developments of graphical models, a number of different graphical modeling software programs have been written over the years. In recent years many...... of these software developments have taken place within the R community, either in the form of new packages or by providing an R ingerface to existing software. This book attempts to give the reader a gentle introduction to graphical modeling using R and the main features of some of these packages. In addition......, the book provides examples of how more advanced aspects of graphical modeling can be represented and handled within R. Topics covered in the seven chapters include graphical models for contingency tables, Gaussian and mixed graphical models, Bayesian networks and modeling high dimensional data...
Emissions Modeling Clearinghouse
U.S. Environmental Protection Agency — The Emissions Modeling Clearinghouse (EMCH) supports and promotes emissions modeling activities both internal and external to the EPA. Through this site, the EPA...
National Oceanic and Atmospheric Administration, Department of Commerce — The World Magnetic Model is the standard model used by the U.S. Department of Defense, the U.K. Ministry of Defence, the North Atlantic Treaty Organization (NATO)...
DEFF Research Database (Denmark)
Lichtenberg, Jakob; Hansen, Michael Reichhardt; Rischel, Hans
1998-01-01
This paper presents a solution to the Invoicing case study using the Standard ML programming language for modelling.......This paper presents a solution to the Invoicing case study using the Standard ML programming language for modelling....
Modeling Philosophies and Applications
All models begin with a framework and a set of assumptions and limitations that go along with that framework. In terms of fracing and RA, there are several places where models and parameters must be chosen to complete hazard identification.
DEFF Research Database (Denmark)
Riis, Troels; Jørgensen, John Leif
1999-01-01
This documents describes a test of the implementation of the ASC orbit model for the Champ satellite.......This documents describes a test of the implementation of the ASC orbit model for the Champ satellite....
Bounding Species Distribution Models
Stohlgren, Thomas J.; Jarnevich, Cahterine S.; Morisette, Jeffrey T.; Esaias, Wayne E.
2011-01-01
Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for "clamping" model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART) and maximum entropy (Maxent) models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5): 642-647, 2011].
Bennett, Joan
1998-01-01
Recommends the use of a model of DNA made out of Velcro to help students visualize the steps of DNA replication. Includes a materials list, construction directions, and details of the demonstration using the model parts. (DDR)
Agena, S. M.; Pusey, M. L.; Bogle, I. D.
1999-01-01
A thermodynamic framework (UNIQUAC model with temperature dependent parameters) is applied to model the salt-induced protein crystallization equilibrium, i.e., protein solubility. The framework introduces a term for the solubility product describing protein transfer between the liquid and solid phase and a term for the solution behavior describing deviation from ideal solution. Protein solubility is modeled as a function of salt concentration and temperature for a four-component system consisting of a protein, pseudo solvent (water and buffer), cation, and anion (salt). Two different systems, lysozyme with sodium chloride and concanavalin A with ammonium sulfate, are investigated. Comparison of the modeled and experimental protein solubility data results in an average root mean square deviation of 5.8%, demonstrating that the model closely follows the experimental behavior. Model calculations and model parameters are reviewed to examine the model and protein crystallization process. Copyright 1999 John Wiley & Sons, Inc.
Amir Farbin
The ATLAS Analysis Model is a continually developing vision of how to reconcile physics analysis requirements with the ATLAS offline software and computing model constraints. In the past year this vision has influenced the evolution of the ATLAS Event Data Model, the Athena software framework, and physics analysis tools. These developments, along with the October Analysis Model Workshop and the planning for CSC analyses have led to a rapid refinement of the ATLAS Analysis Model in the past few months. This article introduces some of the relevant issues and presents the current vision of the future ATLAS Analysis Model. Event Data Model The ATLAS Event Data Model (EDM) consists of several levels of details, each targeted for a specific set of tasks. For example the Event Summary Data (ESD) stores calorimeter cells and tracking system hits thereby permitting many calibration and alignment tasks, but will be only accessible at particular computing sites with potentially large latency. In contrast, the Analysis...
Rouder, Jeffrey N; Engelhardt, Christopher R; McCabe, Simon; Morey, Richard D
2016-12-01
Analysis of variance (ANOVA), the workhorse analysis of experimental designs, consists of F-tests of main effects and interactions. Yet, testing, including traditional ANOVA, has been recently critiqued on a number of theoretical and practical grounds. In light of these critiques, model comparison and model selection serve as an attractive alternative. Model comparison differs from testing in that one can support a null or nested model vis-a-vis a more general alternative by penalizing more flexible models. We argue this ability to support more simple models allows for more nuanced theoretical conclusions than provided by traditional ANOVA F-tests. We provide a model comparison strategy and show how ANOVA models may be reparameterized to better address substantive questions in data analysis.
Directory of Open Access Journals (Sweden)
Oleg Svatos
2013-01-01
Full Text Available In this paper we analyze complexity of time limits we can find especially in regulated processes of public administration. First we review the most popular process modeling languages. There is defined an example scenario based on the current Czech legislature which is then captured in discussed process modeling languages. Analysis shows that the contemporary process modeling languages support capturing of the time limit only partially. This causes troubles to analysts and unnecessary complexity of the models. Upon unsatisfying results of the contemporary process modeling languages we analyze the complexity of the time limits in greater detail and outline lifecycles of a time limit using the multiple dynamic generalizations pattern. As an alternative to the popular process modeling languages there is presented PSD process modeling language, which supports the defined lifecycles of a time limit natively and therefore allows keeping the models simple and easy to understand.
2014-01-01
This study developed a new snow model and a database which warehouses geometric, weather and traffic : data on New Jersey highways. The complexity of the model development lies in considering variable road : width, different spreading/plowing pattern...
National Aeronautics and Space Administration — The Galactic model is a spatial and spectral template. The model for the Galactic diffuse emission was developed using spectral line surveys of HI and CO (as a...
Modeling Touch and Palpation Using Autoregressive Models.
Laufer, Shlomi; Pugh, Carla; Van Veen, Barry D
2017-05-05
The human haptic system uses a set of reproducible and subconscious hand maneuvers to identify objects. Similar subconscious maneuvers are used during medical palpation for screening and diagnosis. The goal of this work was to develop a mathematical model that can be used to describe medical palpation techniques. Palpation data were measured using a two-dimensional array of force sensors. A novel algorithm for estimating the hand position from force data was developed. The hand position data were then modeled using multi-variate autoregressive models. Analysis of these models provided palpation direction and frequency as well as palpation type. The models were tested and validated using three different data sets: simulated data, a simplified experiment in which participant followed a known pattern and breast simulator palpation data. Simulated data showed that minimal error in estimating palpation direction and frequency is achieved when the sampling frequency is five to ten times the palpation frequency. The classification accuracy was 99% for the simplified experiment and 73% for the breast simulator data. Proper palpation is one of the vital components of many hands-on clinical examinations. In this study an algorithm for characterizing medical palpation was developed. The algorithm measured palpation frequency and direction for the first time and provided classification of palpation type. These newly developed models can be used for quantifying and assessing clinical technique and consequently lead to improved performance in palpation-based exams. Furthermore, they provide a general tool for the study of human haptics.
Modelling pelagic biogeography
Olson, Donald B.; Hood, Raleigh R.
Various combinations of physical and biological models are used to explore factors that determine the distribution of organisms in the world's oceans. The physical models examined include simple box models with parameterized inter-box exchanges that take into account variable box geometries, and specified continuous flows either in the Eulerian frame as stream-functions or as Lagrangian trajectories. A 1-dimensional mixed-layer model and a primitive equation channel model are introduced as examples of dynamical models depicting ocean physics. Biological models are discussed starting with a simple nitrogen (N), phytoplankton (P), zooplankton (Z) and detritus (D), NPZD formulation. The equilibria of this model is explored analytically as an example of computing steady state solutions, and then considering where in parameter space extinction occurs. Nonlinearities and expansion of NPZD to multi-species models are also treated. This is followed by the introduction of a nonlinear three-component food chain model, multi-species Lotka-Voltera competition models, and finally a discussion of structured population models including a derivation of a genetics model written in terms of genotypes. The physical models are then coupled with the biological ones in a series of examples. Both the box model with Lotka-Voltera multi-species population dynamics, and the 1-dimensional mixed-layer model with NPZD are used to demonstrate how the existence of spatial and temporal niches can allow a large number of species to coexist within biogeographic domains even though conditions at most sites and times are not conducive to supporting such diversity. These models recreate the basic diversity patterns observed in the pelagic ecosystem at various latitudes. The box model simulations also demonstrate the tendency for diffusive models to overestimate the dispersion of a species. In order to explore the dynamics of the edges of biogeographic domains a three species food chain model is
Optimization modeling with spreadsheets
Baker, Kenneth R
2015-01-01
An accessible introduction to optimization analysis using spreadsheets Updated and revised, Optimization Modeling with Spreadsheets, Third Edition emphasizes model building skills in optimization analysis. By emphasizing both spreadsheet modeling and optimization tools in the freely available Microsoft® Office Excel® Solver, the book illustrates how to find solutions to real-world optimization problems without needing additional specialized software. The Third Edition includes many practical applications of optimization models as well as a systematic framework that il
Petrone, Giovanni; Spagnuolo, Giovanni
2016-01-01
This comprehensive guide surveys all available models for simulating a photovoltaic (PV) generator at different levels of granularity, from cell to system level, in uniform as well as in mismatched conditions. Providing a thorough comparison among the models, engineers have all the elements needed to choose the right PV array model for specific applications or environmental conditions matched with the model of the electronic circuit used to maximize the PV power production.
Model Checking Feature Interactions
DEFF Research Database (Denmark)
Le Guilly, Thibaut; Olsen, Petur; Pedersen, Thomas
2015-01-01
This paper presents an offline approach to analyzing feature interactions in embedded systems. The approach consists of a systematic process to gather the necessary information about system components and their models. The model is first specified in terms of predicates, before being refined to t...... to timed automata. The consistency of the model is verified at different development stages, and the correct linkage between the predicates and their semantic model is checked. The approach is illustrated on a use case from home automation....
Artificial neural network modelling
Samarasinghe, Sandhya
2016-01-01
This book covers theoretical aspects as well as recent innovative applications of Artificial Neural networks (ANNs) in natural, environmental, biological, social, industrial and automated systems. It presents recent results of ANNs in modelling small, large and complex systems under three categories, namely, 1) Networks, Structure Optimisation, Robustness and Stochasticity 2) Advances in Modelling Biological and Environmental Systems and 3) Advances in Modelling Social and Economic Systems. The book aims at serving undergraduates, postgraduates and researchers in ANN computational modelling. .
DEFF Research Database (Denmark)
Thoft-Christensen, Palle
Modelling of corrosion cracking of reinforced concrete structures is complicated as a great number of uncertain factors are involved. To get a reliable modelling a physical and mechanical understanding of the process behind corrosion in needed.......Modelling of corrosion cracking of reinforced concrete structures is complicated as a great number of uncertain factors are involved. To get a reliable modelling a physical and mechanical understanding of the process behind corrosion in needed....
GARCH Modelling of Cryptocurrencies
Jeffrey Chu; Stephen Chan; Saralees Nadarajah; Joerg Osterrieder
2017-01-01
With the exception of Bitcoin, there appears to be little or no literature on GARCH modelling of cryptocurrencies. This paper provides the first GARCH modelling of the seven most popular cryptocurrencies. Twelve GARCH models are fitted to each cryptocurrency, and their fits are assessed in terms of five criteria. Conclusions are drawn on the best fitting models, forecasts and acceptability of value at risk estimates.
Anderberg, Yngve
1986-01-01
When modelling material mechanical behaviour, an analytical description is required of the relationship between stresses and strains. A computer oriented mechanical behaviour model for steel is described. The model is based on the fact that the deformation process at transient high temperature conditions can be desribed by three strain components which are separately found in different steady state tests. It is shown that a behaviour model based on steady state data satisfactorily predicts be...
GARCH Modelling of Cryptocurrencies
Directory of Open Access Journals (Sweden)
Jeffrey Chu
2017-10-01
Full Text Available With the exception of Bitcoin, there appears to be little or no literature on GARCH modelling of cryptocurrencies. This paper provides the first GARCH modelling of the seven most popular cryptocurrencies. Twelve GARCH models are fitted to each cryptocurrency, and their fits are assessed in terms of five criteria. Conclusions are drawn on the best fitting models, forecasts and acceptability of value at risk estimates.
Modeling anomalous superdiffusion
Energy Technology Data Exchange (ETDEWEB)
Fischer, A [Institut fuer Physik, Technische Universitaet Chemnitz, D-09107 Chemnitz (Germany); Seeger, S [Institut fuer Physik, Technische Universitaet Chemnitz, D-09107 Chemnitz (Germany); Hoffmann, K H [Institut fuer Physik, Technische Universitaet Chemnitz, D-09107 Chemnitz (Germany); Essex, C [Department of Applied Mathematics, The University of Western Ontario, London N6A (Canada); Davison, M [Department of Applied Mathematics, The University of Western Ontario, London N6A (Canada)
2007-09-21
Continuous models for anomalous diffusion have previously been tested in the subdiffusive case by making comparisons to diffusion on a Sierpinski gasket. This paper extends this discussion to the superdiffusive case by comparing performance to diffusion on a tree model. Although there is reasonable agreement within limited regimes for all four models, one model, due to Compte and Jou, stands out as being consistently sound over all regimes studied.
Validation of simulation models
DEFF Research Database (Denmark)
Rehman, Muniza; Pedersen, Stig Andur
2012-01-01
In philosophy of science, the interest for computational models and simulations has increased heavily during the past decades. Different positions regarding the validity of models have emerged but the views have not succeeded in capturing the diversity of validation methods. The wide variety...... of models has been somewhat narrow-minded reducing the notion of validation to establishment of truth. This article puts forward the diversity in applications of simulation models that demands a corresponding diversity in the notion of validation....
Modelling Railway Interlocking Systems
DEFF Research Database (Denmark)
Lindegaard, Morten Peter; Viuf, P.; Haxthausen, Anne Elisabeth
2000-01-01
In this report we present a model of interlocking systems, and describe how the model may be validated by simulation. Station topologies are modelled by graphs in which the nodes denote track segments, and the edges denote connectivity for train traÆc. Points and signals are modelled by annotations...... on the edges, thereby restricting the driving possibilities. We de ne the safe station states as predicates on the graph, and present a rst step towards an implementation of these predicates....
computer modeling ter modeling ter modeling of platinum reforming
African Journals Online (AJOL)
eobe
Usually, the reformate that is leaving any stage o composition is assessed by laboratory analysis. The i which in most cases is avoided because of long comp hich in most cases is avoided because of long comp approach has considered a computer model as mean bed reactors in platforming u bed reactors in platforming ...
Modelling agricultural production
Wit, de C.T.
1986-01-01
In modelling in general and biological modelling in particular two approaches may be distinguished: a descriptive and an explanatory approach. In descriptive models the system and its behaviour are described at the same level at which the observations about it are made. A good example are the
Foss, Nicolai; Stieglitz, Nils
2014-01-01
We draw on the complementarity literature in economics and management research to dimensionalize business models innovations. Specifically, such innovation can be dimensionalized in terms of the depth and the breadth of the changes to the company’s business model that they imply. In turn, different business model innovations are associated with different management challenges and require different leadership interventions to become successful.
Adsorption-desorption reactions are important processes that affect the transport of contaminants in the environment. Surface complexation models are chemical models that can account for the effects of variable chemical conditions, such as pH, on adsorption reactions. These models define specific ...
Energy Technology Data Exchange (ETDEWEB)
Fortelius, C.; Holopainen, E.; Kaurola, J.; Ruosteenoja, K.; Raeisaenen, J. [Helsinki Univ. (Finland). Dept. of Meteorology
1996-12-31
In recent years the modelling of interannual climate variability has been studied, the atmospheric energy and water cycles, and climate simulations with the ECHAM3 model. In addition, the climate simulations of several models have been compared with special emphasis in the area of northern Europe
Khuri, Andre I
2009-01-01
Supported by a large number of examples, this book provides a foundation in the theory of linear models and explores the developments in data analysis. It encompasses a wide variety of topics in linear models that incorporate the classical approach and other trends and modeling techniques.
Energy Technology Data Exchange (ETDEWEB)
C. Lum
2004-09-16
The purpose of this model report is to document the Rock Properties Model version 3.1 with regard to input data, model methods, assumptions, uncertainties and limitations of model results, and qualification status of the model. The report also documents the differences between the current and previous versions and validation of the model. The rock properties model provides mean matrix and lithophysae porosity, and the cross-correlated mean bulk density as direct input to the ''Saturated Zone Flow and Transport Model Abstraction'', MDL-NBS-HS-000021, REV 02 (BSC 2004 [DIRS 170042]). The constraints, caveats, and limitations associated with this model are discussed in Section 6.6 and 8.2. Model validation accomplished by corroboration with data not cited as direct input is discussed in Section 7. The revision of this model report was performed as part of activities being conducted under the ''Technical Work Plan for: The Integrated Site Model, Revision 05'' (BSC 2004 [DIRS 169635]). The purpose of this revision is to bring the report up to current procedural requirements and address the Regulatory Integration Team evaluation comments. The work plan describes the scope, objectives, tasks, methodology, and procedures for this process.
Model Breaking Points Conceptualized
Vig, Rozy; Murray, Eileen; Star, Jon R.
2014-01-01
Current curriculum initiatives (e.g., National Governors Association Center for Best Practices and Council of Chief State School Officers 2010) advocate that models be used in the mathematics classroom. However, despite their apparent promise, there comes a point when models break, a point in the mathematical problem space where the model cannot,…
DEFF Research Database (Denmark)
Galle, Per
2000-01-01
In preparation of an analysis of product modelling in terms of communication, this report presents a brief analysis of symbols; that is, the entities by means of which communication takes place. Symbols are defined in such a way as to admit artefacts and models (the latter including linguistic...... utterances as well as scale models) as special cases....
Walsh, Jim; McGehee, Richard
2013-01-01
A dynamical systems approach to energy balance models of climate is presented, focusing on low order, or conceptual, models. Included are global average and latitude-dependent, surface temperature models. The development and analysis of the differential equations and corresponding bifurcation diagrams provides a host of appropriate material for…
Thornton, Bradley D.; Smalley, Robert A.
2008-01-01
Building information modeling (BIM) uses three-dimensional modeling concepts, information technology and interoperable software to design, construct and operate a facility. However, BIM can be more than a tool for virtual modeling--it can provide schools with a 3-D walkthrough of a project while it still is on the electronic drawing board. BIM can…
Subjects, Models, Languages, Transformations
Rensink, Arend; Bézivin, J.; Heckel, R.
2005-01-01
Discussions about model-driven approaches tend to be hampered by terminological confusion. This is at least partially caused by a lack of formal precision in defining the basic concepts, including that of "model" and "thing being modelled" - which we call subject in this paper. We propose a minimal
Bogiages, Christopher A.; Lotter, Christine
2011-01-01
In their research, scientists generate, test, and modify scientific models. These models can be shared with others and demonstrate a scientist's understanding of how the natural world works. Similarly, students can generate and modify models to gain a better understanding of the content, process, and nature of science (Kenyon, Schwarz, and Hug…
Modeling EERE Deployment Programs
Energy Technology Data Exchange (ETDEWEB)
Cort, K. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hostick, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Belzer, D. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Livingston, O. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2007-11-01
This report compiles information and conclusions gathered as part of the “Modeling EERE Deployment Programs” project. The purpose of the project was to identify and characterize the modeling of deployment programs within the EERE Technology Development (TD) programs, address possible improvements to the modeling process, and note gaps in knowledge in which future research is needed.
Modeling and Remodeling Writing
Hayes, John R.
2012-01-01
In Section 1 of this article, the author discusses the succession of models of adult writing that he and his colleagues have proposed from 1980 to the present. He notes the most important changes that differentiate earlier and later models and discusses reasons for the changes. In Section 2, he describes his recent efforts to model young…
Richard Haynes; Darius Adams; Peter Ince; John Mills; Ralph Alig
2006-01-01
The United States has a century of experience with the development of models that describe markets for forest products and trends in resource conditions. In the last four decades, increasing rigor in policy debates has stimulated the development of models to support policy analysis. Increasingly, research has evolved (often relying on computer-based models) to increase...
Modeling Epidemic Network Failures
DEFF Research Database (Denmark)
Ruepp, Sarah Renée; Fagertun, Anna Manolova
2013-01-01
This paper presents the implementation of a failure propagation model for transport networks when multiple failures occur resulting in an epidemic. We model the Susceptible Infected Disabled (SID) epidemic model and validate it by comparing it to analytical solutions. Furthermore, we evaluate...
DEFF Research Database (Denmark)
Jensen, Finn Verner; Nielsen, Thomas Dyhre
2016-01-01
Mathematically, a Bayesian graphical model is a compact representation of the joint probability distribution for a set of variables. The most frequently used type of Bayesian graphical models are Bayesian networks. The structural part of a Bayesian graphical model is a graph consisting of nodes...
E. Gregory McPherson; Paula J. Peper
2012-01-01
This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...
Hydrological land surface modelling
DEFF Research Database (Denmark)
Ridler, Marc-Etienne Francois
and disaster management. The objective of this study is to develop and investigate methods to reduce hydrological model uncertainty by using supplementary data sources. The data is used either for model calibration or for model updating using data assimilation. Satellite estimates of soil moisture and surface...
DEFF Research Database (Denmark)
Andreasen, Martin Møller; Meldrum, Andrew
This paper studies whether dynamic term structure models for US nominal bond yields should enforce the zero lower bound by a quadratic policy rate or a shadow rate specification. We address the question by estimating quadratic term structure models (QTSMs) and shadow rate models with at most four...
DEFF Research Database (Denmark)
Cameron, Ian; Gani, Rafiqul
2011-01-01
Engineering of products and processes is increasingly “model-centric”. Models in their multitudinous forms are ubiquitous, being heavily used for a range of decision making activities across all life cycle phases. This chapter gives an overview of what is a model, the principal activities in the ...
Fedorov, Alexander
2011-01-01
The author supposed that media education models can be divided into the following groups: (1) educational-information models (the study of the theory, history, language of media culture, etc.), based on the cultural, aesthetic, semiotic, socio-cultural theories of media education; (2) educational-ethical models (the study of moral, religions,…
Classifying variability modeling techniques
Sinnema, Marco; Deelstra, Sybren
Variability modeling is important for managing variability in software product families, especially during product derivation. In the past few years, several variability modeling techniques have been developed, each using its own concepts to model the variability provided by a product family. The
Modeling of ultrasound transducers
DEFF Research Database (Denmark)
Bæk, David
This Ph.D. dissertation addresses ultrasound transducer modeling for medical ultrasound imaging and combines the modeling with the ultrasound simulation program Field II. The project firstly presents two new models for spatial impulse responses (SIR)s to a rectangular elevation focused transducer...
Kelderman, Hendrikus
1984-01-01
Existing statistical tests for the fit of the Rasch model have been criticized, because they are only sensitive to specific violations of its assumptions. Contingency table methods using loglinear models have been used to test various psychometric models. In this paper, the assumptions of the Rasch
Dynamic Latent Classification Model
DEFF Research Database (Denmark)
Zhong, Shengtong; Martínez, Ana M.; Nielsen, Thomas Dyhre
as possible. Motivated by this problem setting, we propose a generative model for dynamic classification in continuous domains. At each time point the model can be seen as combining a naive Bayes model with a mixture of factor analyzers (FA). The latent variables of the FA are used to capture the dynamics...
Flexible survival regression modelling
DEFF Research Database (Denmark)
Cortese, Giuliana; Scheike, Thomas H; Martinussen, Torben
2009-01-01
Regression analysis of survival data, and more generally event history data, is typically based on Cox's regression model. We here review some recent methodology, focusing on the limitations of Cox's regression model. The key limitation is that the model is not well suited to represent time-varyi...
DEFF Research Database (Denmark)
Bergdahl, Basti; Sonnenschein, Nikolaus; Machado, Daniel
2016-01-01
An introduction to genome-scale models, how to build and use them, will be given in this chapter. Genome-scale models have become an important part of systems biology and metabolic engineering, and are increasingly used in research, both in academica and in industry, both for modeling chemical...
Automated Simulation Model Generation
Huang, Y.
2013-01-01
One of today's challenges in the field of modeling and simulation is to model increasingly larger and more complex systems. Complex models take long to develop and incur high costs. With the advances in data collection technologies and more popular use of computer-aided systems, more data has become
DEFF Research Database (Denmark)
Friis, Silje Alberthe Kamille; Gelting, Anne Katrine Gøtzsche
2014-01-01
the approaches and reach a new level of conscious action when designing? Informed by theories of design thinking, knowledge production, and learning, we have developed a model, the 5C model, accompanied by 62 method cards. Examples of how the model has been applied in an educational setting are provided...
Modeling agriculture in the Community Land Model
Directory of Open Access Journals (Sweden)
B. Drewniak
2013-04-01
Full Text Available The potential impact of climate change on agriculture is uncertain. In addition, agriculture could influence above- and below-ground carbon storage. Development of models that represent agriculture is necessary to address these impacts. We have developed an approach to integrate agriculture representations for three crop types – maize, soybean, and spring wheat – into the coupled carbon–nitrogen version of the Community Land Model (CLM, to help address these questions. Here we present the new model, CLM-Crop, validated against observations from two AmeriFlux sites in the United States, planted with maize and soybean. Seasonal carbon fluxes compared well with field measurements for soybean, but not as well for maize. CLM-Crop yields were comparable with observations in countries such as the United States, Argentina, and China, although the generality of the crop model and its lack of technology and irrigation made direct comparison difficult. CLM-Crop was compared against the standard CLM3.5, which simulates crops as grass. The comparison showed improvement in gross primary productivity in regions where crops are the dominant vegetation cover. Crop yields and productivity were negatively correlated with temperature and positively correlated with precipitation, in agreement with other modeling studies. In case studies with the new crop model looking at impacts of residue management and planting date on crop yield, we found that increased residue returned to the litter pool increased crop yield, while reduced residue returns resulted in yield decreases. Using climate controls to signal planting date caused different responses in different crops. Maize and soybean had opposite reactions: when low temperature threshold resulted in early planting, maize responded with a loss of yield, but soybean yields increased. Our improvements in CLM demonstrate a new capability in the model – simulating agriculture in a realistic way, complete with
Long, John
2014-01-01
Process Modeling Style focuses on other aspects of process modeling beyond notation that are very important to practitioners. Many people who model processes focus on the specific notation used to create their drawings. While that is important, there are many other aspects to modeling, such as naming, creating identifiers, descriptions, interfaces, patterns, and creating useful process documentation. Experience author John Long focuses on those non-notational aspects of modeling, which practitioners will find invaluable. Gives solid advice for creating roles, work produ
Meister, Jeffrey P.
1987-01-01
The Mechanics of Materials Model (MOMM) is a three-dimensional inelastic structural analysis code for use as an early design stage tool for hot section components. MOMM is a stiffness method finite element code that uses a network of beams to characterize component behavior. The MOMM contains three material models to account for inelastic material behavior. These include the simplified material model, which assumes a bilinear stress-strain response; the state-of-the-art model, which utilizes the classical elastic-plastic-creep strain decomposition; and Walker's viscoplastic model, which accounts for the interaction between creep and plasticity that occurs under cyclic loading conditions.
DEFF Research Database (Denmark)
Sommerlund, Julie
from laboratory studies, (Latour 1979; Lynch 1985; Sommerlund 2004 (2007); Sommerlund 2006) and is complemented by the attention paid to the "mediator" by Hennion (1989; 1997; 2005). The empirical focus will be on a central - but overlooked - actor of branding and advertising; the model. The model has...... solely been theorized within cultural studies (Craik 1994) as feminine spectacle, but has been neglected as mediator and actor. This paper will argue that models are co-producers of brands, and vice versa. Empirically, the paper will present interviews with models, model-scouts, agents, and advertisers...
Energy Technology Data Exchange (ETDEWEB)
Brown, T.W.
2010-11-15
The same complex matrix model calculates both tachyon scattering for the c=1 non-critical string at the self-dual radius and certain correlation functions of half-BPS operators in N=4 super- Yang-Mills. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich- Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces. (orig.)
Mathematical modelling techniques
Aris, Rutherford
1995-01-01
""Engaging, elegantly written."" - Applied Mathematical ModellingMathematical modelling is a highly useful methodology designed to enable mathematicians, physicists and other scientists to formulate equations from a given nonmathematical situation. In this elegantly written volume, a distinguished theoretical chemist and engineer sets down helpful rules not only for setting up models but also for solving the mathematical problems they pose and for evaluating models.The author begins with a discussion of the term ""model,"" followed by clearly presented examples of the different types of mode
Energy Technology Data Exchange (ETDEWEB)
Ritchie, L.T.; Alpert, D.J.; Burke, R.P.; Johnson, J.D.; Ostmeyer, R.M.; Aldrich, D.C.; Blond, R.M.
1984-03-01
The CRAC2 computer code is a revised version of CRAC (Calculation of Reactor Accident Consequences) which was developed for the Reactor Safety Study. This document provides an overview of the CRAC2 code and a description of each of the models used. Significant improvements incorporated into CRAC2 include an improved weather sequence sampling technique, a new evacuation model, and new output capabilities. In addition, refinements have been made to the atmospheric transport and deposition model. Details of the modeling differences between CRAC2 and CRAC are emphasized in the model descriptions.
DEFF Research Database (Denmark)
Ibsen, Lars Bo; Liingaard, Morten
A lumped-parameter model represents the frequency dependent soil-structure interaction of a massless foundation placed on or embedded into an unbounded soil domain. The lumped-parameter model development have been reported by (Wolf 1991b; Wolf 1991a; Wolf and Paronesso 1991; Wolf and Paronesso 1992......; Wolf 1994; Wolf 1997; Wu and Lee 2002; Wu and Lee 2004). In this technical report the the steps of establishing a lumped-parameter model are presented. Following sections are included in this report: Static and dynamic formulation (Section 1.1), Simple lumped-parameter models (Section 1.2) and Advanced...... lumped-parameter models (Section 1.3)....
Making ecological models adequate
Getz, Wayne M.; Marshall, Charles R.; Carlson, Colin J.; Giuggioli, Luca; Ryan, Sadie J.; Romañach, Stephanie; Boettiger, Carl; Chamberlain, Samuel D.; Larsen, Laurel; D'Odorico, Paolo; O'Sullivan, David
2018-01-01
Critical evaluation of the adequacy of ecological models is urgently needed to enhance their utility in developing theory and enabling environmental managers and policymakers to make informed decisions. Poorly supported management can have detrimental, costly or irreversible impacts on the environment and society. Here, we examine common issues in ecological modelling and suggest criteria for improving modelling frameworks. An appropriate level of process description is crucial to constructing the best possible model, given the available data and understanding of ecological structures. Model details unsupported by data typically lead to over parameterisation and poor model performance. Conversely, a lack of mechanistic details may limit a model's ability to predict ecological systems’ responses to management. Ecological studies that employ models should follow a set of model adequacy assessment protocols that include: asking a series of critical questions regarding state and control variable selection, the determinacy of data, and the sensitivity and validity of analyses. We also need to improve model elaboration, refinement and coarse graining procedures to better understand the relevancy and adequacy of our models and the role they play in advancing theory, improving hind and forecasting, and enabling problem solving and management.
Guenther, D. B.; Demarque, P.; Kim, Y.-C.; Pinsonneault, M. H.
1992-01-01
A set of solar models have been constructed, each based on a single modification to the physics of a reference solar model. In addition, a model combining several of the improvements has been calculated to provide a best solar model. Improvements were made to the nuclear reaction rates, the equation of state, the opacities, and the treatment of the atmosphere. The impact on both the structure and the frequencies of the low-l p-modes of the model to these improvements are discussed. It is found that the combined solar model, which is based on the best physics available (and does not contain any ad hoc assumptions), reproduces the observed oscillation spectrum (for low-l) within the errors associated with the uncertainties in the model physics (primarily opacities).
DEFF Research Database (Denmark)
Laursen, Jesper
hydrofoil shaped propellers. These two sub-processes deliver the main part of the supplied energy to the activated sludge tank, and for this reason they are important for the mixing conditions in the tank. For other important processes occurring in the activated sludge tank, existing models and measurements...... zones in mind, its special construction poses strict demands to the hydrodynamic model. In case study three the model is extended to a three-phase model where also the injection of air bubbles during the aeration process is modeled. The aeration of sludge is controlled through a simple expression...... for the reoxygenation of the wastewater phase as a function of the local volume fraction of air and the concentration of soluble oxygen. A simple model for the bulk consumption of oxygen is linked to the reoxygenation expression in order to model measured oxygen concentrations in the suspension. In the final case study...
Modelling of wastewater systems
DEFF Research Database (Denmark)
Bechmann, Henrik
to analyze and quantify the effect of the Aeration Tank Settling (ATS) operating mode, which is used during rain events. Furthermore, the model is used to propose a control algorithm for the phase lengths during ATS operation. The models are mainly formulated as state space model in continuous time...... with discrete-time observation equations. The state equations are thus expressed in stochastic differential equations. Hereby it is possible to use the maximum likelihood estimation method to estimate the parameters of the models. A Kalman filter is used to estimate the one-step ahead predictions that are used...... at modelling the fluxes in terms of the multiple correlation coefficient R2. The model of the SS concentrations in the aeration tanks of an alternating WWTP as well as in the effluent from the aeration tanks is a mass balance model based on measurements of SS in one aeration tank and in the common outlet...
Directory of Open Access Journals (Sweden)
Alexander Fedorov
2011-03-01
Full Text Available The author supposed that media education models can be divided into the following groups:- educational-information models (the study of the theory, history, language of media culture, etc., based on the cultural, aesthetic, semiotic, socio-cultural theories of media education;- educational-ethical models (the study of moral, religions, philosophical problems relying on the ethic, religious, ideological, ecological, protectionist theories of media education;- pragmatic models (practical media technology training, based on the uses and gratifications and ‘practical’ theories of media education;- aesthetical models (aimed above all at the development of the artistic taste and enriching the skills of analysis of the best media culture examples. Relies on the aesthetical (art and cultural studies theory; - socio-cultural models (socio-cultural development of a creative personality as to the perception, imagination, visual memory, interpretation analysis, autonomic critical thinking, relying on the cultural studies, semiotic, ethic models of media education.
Energy Technology Data Exchange (ETDEWEB)
Moffat, Harry K.; Noble, David R.; Baer, Thomas A. (Procter & Gamble Co., West Chester, OH); Adolf, Douglas Brian; Rao, Rekha Ranjana; Mondy, Lisa Ann
2008-09-01
In this report, we summarize our work on developing a production level foam processing computational model suitable for predicting the self-expansion of foam in complex geometries. The model is based on a finite element representation of the equations of motion, with the movement of the free surface represented using the level set method, and has been implemented in SIERRA/ARIA. An empirically based time- and temperature-dependent density model is used to encapsulate the complex physics of foam nucleation and growth in a numerically tractable model. The change in density with time is at the heart of the foam self-expansion as it creates the motion of the foam. This continuum-level model uses an homogenized description of foam, which does not include the gas explicitly. Results from the model are compared to temperature-instrumented flow visualization experiments giving the location of the foam front as a function of time for our EFAR model system.
Hydrological land surface modelling
DEFF Research Database (Denmark)
Ridler, Marc-Etienne Francois
Recent advances in integrated hydrological and soil-vegetation-atmosphere transfer (SVAT) modelling have led to improved water resource management practices, greater crop production, and better flood forecasting systems. However, uncertainty is inherent in all numerical models ultimately leading...... and disaster management. The objective of this study is to develop and investigate methods to reduce hydrological model uncertainty by using supplementary data sources. The data is used either for model calibration or for model updating using data assimilation. Satellite estimates of soil moisture and surface...... hydrological and tested by assimilating synthetic hydraulic head observations in a catchment in Denmark. Assimilation led to a substantial reduction of model prediction error, and better model forecasts. Also, a new assimilation scheme is developed to downscale and bias-correct coarse satellite derived soil...
Energy Technology Data Exchange (ETDEWEB)
Shipman, Galen M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-06-13
These are the slides for a presentation on programming models in HPC, at the Los Alamos National Laboratory's Parallel Computing Summer School. The following topics are covered: Flynn's Taxonomy of computer architectures; single instruction single data; single instruction multiple data; multiple instruction multiple data; address space organization; definition of Trinity (Intel Xeon-Phi is a MIMD architecture); single program multiple data; multiple program multiple data; ExMatEx workflow overview; definition of a programming model, programming languages, runtime systems; programming model and environments; MPI (Message Passing Interface); OpenMP; Kokkos (Performance Portable Thread-Parallel Programming Model); Kokkos abstractions, patterns, policies, and spaces; RAJA, a systematic approach to node-level portability and tuning; overview of the Legion Programming Model; mapping tasks and data to hardware resources; interoperability: supporting task-level models; Legion S3D execution and performance details; workflow, integration of external resources into the programming model.
Integrated modeling, data transfers, and physical models
Brookshire, D. S.; Chermak, J. M.
2003-04-01
Difficulties in developing precise economic policy models for water reallocation and re-regulation in various regional and transboundary settings has been exacerbated not only by climate issues but also by institutional changes reflected in the promulgation of environmental laws, changing regional populations, and an increased focus on water quality standards. As complexity of the water issues have increased, model development at a micro-policy level is necessary to capture difficult institutional nuances and represent the differing national, regional and stakeholders' viewpoints. More often than not, adequate "local" or specific micro-data are not available in all settings for modeling and policy decisions. Economic policy analysis increasingly deals with this problem through data transfers (transferring results from one study area to another) and significant progress has been made in understanding the issue of the dimensionality of data transfers. This paper explores the conceptual and empirical dimensions of data transfers in the context of integrated modeling when the transfers are not only from the behavioral, but also from the hard sciences. We begin by exploring the domain of transfer issues associated with policy analyses that directly consider uncertainty in both the behavioral and physical science settings. We then, through a stylized, hybrid, economic-engineering model of water supply and demand in the Middle Rio Grand Valley of New Mexico (USA) analyze the impacts of; (1) the relative uncertainty of data transfers methods, (2) the uncertainty of climate data and, (3) the uncertainly of population growth. These efforts are motivated by the need to address the relative importance of more accurate data both from the physical sciences as well as from demography and economics for policy analyses. We evaluate the impacts by empirically addressing (within the Middle Rio Grand model): (1) How much does the surrounding uncertainty of the benefit transfer
Target Scattering Metrics: Model-Model and Model Data comparisons
2017-12-13
www.apl.washington.edu 13 December 2017 To: Kyle Becker, Program Manager Office of Naval Research (ONR 322) 875 North Randolph Street Arlington, VA 22203...and Kyoohui Beal Naval Research Laboratory DTIC Office of Sponsored Programs – UW Closeout APL-UW Grants and Contracts Closeout Coordinator 1...measured synthetic aperture sonar (SAS) data or from numerical models is investigated. Metrics are needed for quantitative comparisons for signals
Energy Technology Data Exchange (ETDEWEB)
Hammerand, Daniel Carl; Scherzinger, William Mark
2007-09-01
The Library of Advanced Materials for Engineering (LAME) provides a common repository for constitutive models that can be used in computational solid mechanics codes. A number of models including both hypoelastic (rate) and hyperelastic (total strain) constitutive forms have been implemented in LAME. The structure and testing of LAME is described in Scherzinger and Hammerand ([3] and [4]). The purpose of the present report is to describe the material models which have already been implemented into LAME. The descriptions are designed to give useful information to both analysts and code developers. Thus far, 33 non-ITAR/non-CRADA protected material models have been incorporated. These include everything from the simple isotropic linear elastic models to a number of elastic-plastic models for metals to models for honeycomb, foams, potting epoxies and rubber. A complete description of each model is outside the scope of the current report. Rather, the aim here is to delineate the properties, state variables, functions, and methods for each model. However, a brief description of some of the constitutive details is provided for a number of the material models. Where appropriate, the SAND reports available for each model have been cited. Many models have state variable aliases for some or all of their state variables. These alias names can be used for outputting desired quantities. The state variable aliases available for results output have been listed in this report. However, not all models use these aliases. For those models, no state variable names are listed. Nevertheless, the number of state variables employed by each model is always given. Currently, there are four possible functions for a material model. This report lists which of these four methods are employed in each material model. As far as analysts are concerned, this information is included only for the awareness purposes. The analyst can take confidence in the fact that model has been properly implemented
Chen, Changyou; Buntine, Wray; Ding, Nan; Xie, Lexing; Du, Lan
2015-02-01
In applications we may want to compare different document collections: they could have shared content but also different and unique aspects in particular collections. This task has been called comparative text mining or cross-collection modeling. We present a differential topic model for this application that models both topic differences and similarities. For this we use hierarchical Bayesian nonparametric models. Moreover, we found it was important to properly model power-law phenomena in topic-word distributions and thus we used the full Pitman-Yor process rather than just a Dirichlet process. Furthermore, we propose the transformed Pitman-Yor process (TPYP) to incorporate prior knowledge such as vocabulary variations in different collections into the model. To deal with the non-conjugate issue between model prior and likelihood in the TPYP, we thus propose an efficient sampling algorithm using a data augmentation technique based on the multinomial theorem. Experimental results show the model discovers interesting aspects of different collections. We also show the proposed MCMC based algorithm achieves a dramatically reduced test perplexity compared to some existing topic models. Finally, we show our model outperforms the state-of-the-art for document classification/ideology prediction on a number of text collections.
Directory of Open Access Journals (Sweden)
Dan Alexandru Anghel
2012-01-01
Full Text Available In semiconductor laser modeling, a good mathematical model gives near-reality results. Three methods of modeling solutions from the rate equations are presented and analyzed. A method based on the rate equations modeled in Simulink to describe quantum well lasers was presented. For different signal types like step function, saw tooth and sinus used as input, a good response of the used equations is obtained. Circuit model resulting from one of the rate equations models is presented and simulated in SPICE. Results show a good modeling behavior. Numerical simulation in MathCad gives satisfactory results for the study of the transitory and dynamic operation at small level of the injection current. The obtained numerical results show the specific limits of each model, according to theoretical analysis. Based on these results, software can be built that integrates circuit simulation and other modeling methods for quantum well lasers to have a tool that model and analysis these devices from all points of view.
Modelling prokaryote gene content
Directory of Open Access Journals (Sweden)
Edward Susko
2006-01-01
Full Text Available The patchy distribution of genes across the prokaryotes may be caused by multiple gene losses or lateral transfer. Probabilistic models of gene gain and loss are needed to distinguish between these possibilities. Existing models allow only single genes to be gained and lost, despite the empirical evidence for multi-gene events. We compare birth-death models (currently the only widely-used models, in which only one gene can be gained or lost at a time to blocks models (allowing gain and loss of multiple genes within a family. We analyze two pairs of genomes: two E. coli strains, and the distantly-related Archaeoglobus fulgidus (archaea and Bacillus subtilis (gram positive bacteria. Blocks models describe the data much better than birth-death models. Our models suggest that lateral transfers of multiple genes from the same family are rare (although transfers of single genes are probably common. For both pairs, the estimated median time that a gene will remain in the genome is not much greater than the time separating the common ancestors of the archaea and bacteria. Deep phylogenetic reconstruction from sequence data will therefore depend on choosing genes likely to remain in the genome for a long time. Phylogenies based on the blocks model are more biologically plausible than phylogenies based on the birth-death model.
Geochemical modeling: a review
Energy Technology Data Exchange (ETDEWEB)
Jenne, E.A.
1981-06-01
Two general families of geochemical models presently exist. The ion speciation-solubility group of geochemical models contain submodels to first calculate a distribution of aqueous species and to secondly test the hypothesis that the water is near equilibrium with particular solid phases. These models may or may not calculate the adsorption of dissolved constituents and simulate the dissolution and precipitation (mass transfer) of solid phases. Another family of geochemical models, the reaction path models, simulates the stepwise precipitation of solid phases as a result of reacting specified amounts of water and rock. Reaction path models first perform an aqueous speciation of the dissolved constituents of the water, test solubility hypotheses, then perform the reaction path modeling. Certain improvements in the present versions of these models would enhance their value and usefulness to applications in nuclear-waste isolation, etc. Mass-transfer calculations of limited extent are certainly within the capabilities of state-of-the-art models. However, the reaction path models require an expansion of their thermodynamic data bases and systematic validation before they are generally accepted.
[Mathematical models of hysteresis
Energy Technology Data Exchange (ETDEWEB)
Mayergoyz, I.D.
1991-01-01
The research described in this proposal is currently being supported by the US Department of Energy under the contract Mathematical Models of Hysteresis''. Thus, before discussing the proposed research in detail, it is worthwhile to describe and summarize the main results achieved in the course of our work under the above contract. Our ongoing research has largely been focused on the development of mathematical models of hysteretic nonlinearities with nonlocal memories''. The distinct feature of these nonlinearities is that their current states depend on past histories of input variations. It turns out that memories of hysteretic nonlinearities are quite selective. Indeed, experiments show that only some past input extrema leave their marks upon future states of hysteretic nonlinearities. Thus special mathematical tools are needed in order to describe nonlocal selective memories of hysteretic nonlinearities. Our research has been primarily concerned with Preisach-type models of hysteresis. All these models have a common generic feature; they are constructed as superpositions of simplest hysteretic nonlinearities-rectangular loops. Our study has by and large been centered around the following topics: various generalizations and extensions of the classical Preisach model, finding of necessary and sufficient conditions for the representation of actual hysteretic nonlinearities by various Preisach type models, solution of identification problems for these models, numerical implementation and experimental testing of Preisach type models. Although the study of Preisach type models has constituted the main direction of the research, some effort has also been made to establish some interesting connections between these models and such topics as: the critical state model for superconducting hysteresis, the classical Stoner-Wohlfarth model of vector magnetic hysteresis, thermal activation type models for viscosity, magnetostrictive hysteresis and neural
Models as Relational Categories
Kokkonen, Tommi
2017-10-01
Model-based learning (MBL) has an established position within science education. It has been found to enhance conceptual understanding and provide a way for engaging students in authentic scientific activity. Despite ample research, few studies have examined the cognitive processes regarding learning scientific concepts within MBL. On the other hand, recent research within cognitive science has examined the learning of so-called relational categories. Relational categories are categories whose membership is determined on the basis of the common relational structure. In this theoretical paper, I argue that viewing models as relational categories provides a well-motivated cognitive basis for MBL. I discuss the different roles of models and modeling within MBL (using ready-made models, constructive modeling, and generative modeling) and discern the related cognitive aspects brought forward by the reinterpretation of models as relational categories. I will argue that relational knowledge is vital in learning novel models and in the transfer of learning. Moreover, relational knowledge underlies the coherent, hierarchical knowledge of experts. Lastly, I will examine how the format of external representations may affect the learning of models and the relevant relations. The nature of the learning mechanisms underlying students' mental representations of models is an interesting open question to be examined. Furthermore, the ways in which the expert-like knowledge develops and how to best support it is in need of more research. The discussion and conceptualization of models as relational categories allows discerning students' mental representations of models in terms of evolving relational structures in greater detail than previously done.
Product modelling for model-based maintenance
van Houten, Frederikus J.A.M.; Tomiyama, T.; Salomons, O.W.
1998-01-01
The paper describes the fundamental concepts of maintenance and the role that information technology can play in the support of maintenance activities. Function-Behaviour-State modelling is used to describe faults and deterioration of mechanisms in terms of user perception and measurable quantities.
Energy Technology Data Exchange (ETDEWEB)
Tan, A; Lyatskaya, I [Department of Physics, Alabama A and M University, Normal, AL 35762 (United States)], E-mail: arjun.tan@aamu.edu
2009-01-15
The interesting papers by Margaritondo (2005 Eur. J. Phys. 26 401) and by Helene and Yamashita (2006 Eur. J. Phys. 27 855) analysed the great Indian Ocean tsunami of 2004 using a simple one-dimensional canal wave model, which was appropriate for undergraduate students in physics and related fields of discipline. In this paper, two additional, easily understandable models, suitable for the same level of readership, are proposed: one, a two-dimensional model in flat space, and two, the same on a spherical surface. The models are used to study the tsunami produced by the central Kuril earthquake of November 2006. It is shown that the two alternative models, especially the latter one, give better representations of the wave amplitude, especially at far-flung locations. The latter model further demonstrates the enhancing effect on the amplitude due to the curvature of the Earth for far-reaching tsunami propagation.
DEFF Research Database (Denmark)
Andersen, Kasper Winther
Three main topics are presented in this thesis. The first and largest topic concerns network modelling of functional Magnetic Resonance Imaging (fMRI) and Diffusion Weighted Imaging (DWI). In particular nonparametric Bayesian methods are used to model brain networks derived from resting state f...... for their ability to reproduce node clustering and predict unseen data. Comparing the models on whole brain networks, BCD and IRM showed better reproducibility and predictability than IDM, suggesting that resting state networks exhibit community structure. This also points to the importance of using models, which...... allow for complex interactions between all pairs of clusters. In addition, it is demonstrated how the IRM can be used for segmenting brain structures into functionally coherent clusters. A new nonparametric Bayesian network model is presented. The model builds upon the IRM and can be used to infer...
Essentials of econophysics modelling
Slanina, Frantisek
2014-01-01
This book is a course in methods and models rooted in physics and used in modelling economic and social phenomena. It covers the discipline of econophysics, which creates an interface between physics and economics. Besides the main theme, it touches on the theory of complex networks and simulations of social phenomena in general. After a brief historical introduction, the book starts with a list of basic empirical data and proceeds to thorough investigation of mathematical and computer models. Many of the models are based on hypotheses of the behaviour of simplified agents. These comprise strategic thinking, imitation, herding, and the gem of econophysics, the so-called minority game. At the same time, many other models view the economic processes as interactions of inanimate particles. Here, the methods of physics are especially useful. Examples of systems modelled in such a way include books of stock-market orders, and redistribution of wealth among individuals. Network effects are investigated in the inter...
Aeroservoelasticity modeling and control
Tewari, Ashish
2015-01-01
This monograph presents the state of the art in aeroservoelastic (ASE) modeling and analysis and develops a systematic theoretical and computational framework for use by researchers and practicing engineers. It is the first book to focus on the mathematical modeling of structural dynamics, unsteady aerodynamics, and control systems to evolve a generic procedure to be applied for ASE synthesis. Existing robust, nonlinear, and adaptive control methodology is applied and extended to some interesting ASE problems, such as transonic flutter and buffet, post-stall buffet and maneuvers, and flapping flexible wing. The author derives a general aeroservoelastic plant via the finite-element structural dynamic model, unsteady aerodynamic models for various regimes in the frequency domain, and the associated state-space model by rational function approximations. For more advanced models, the full-potential, Euler, and Navier-Stokes methods for treating transonic and separated flows are also briefly addressed. Essential A...
Lawson, Andrew B
2002-01-01
Research has generated a number of advances in methods for spatial cluster modelling in recent years, particularly in the area of Bayesian cluster modelling. Along with these advances has come an explosion of interest in the potential applications of this work, especially in epidemiology and genome research. In one integrated volume, this book reviews the state-of-the-art in spatial clustering and spatial cluster modelling, bringing together research and applications previously scattered throughout the literature. It begins with an overview of the field, then presents a series of chapters that illuminate the nature and purpose of cluster modelling within different application areas, including astrophysics, epidemiology, ecology, and imaging. The focus then shifts to methods, with discussions on point and object process modelling, perfect sampling of cluster processes, partitioning in space and space-time, spatial and spatio-temporal process modelling, nonparametric methods for clustering, and spatio-temporal ...
Inverse and Predictive Modeling
Energy Technology Data Exchange (ETDEWEB)
Syracuse, Ellen Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-09-27
The LANL Seismo-Acoustic team has a strong capability in developing data-driven models that accurately predict a variety of observations. These models range from the simple – one-dimensional models that are constrained by a single dataset and can be used for quick and efficient predictions – to the complex – multidimensional models that are constrained by several types of data and result in more accurate predictions. Team members typically build models of geophysical characteristics of Earth and source distributions at scales of 1 to 1000s of km, the techniques used are applicable for other types of physical characteristics at an even greater range of scales. The following cases provide a snapshot of some of the modeling work done by the Seismo- Acoustic team at LANL.
Diaspora Business Model Innovation
Directory of Open Access Journals (Sweden)
Aki Harima
2015-01-01
Full Text Available This paper explores how diasporans achieve business model innovatin by using their unique resources. The hypothesis underlying the paper is that the unique backgrounds and resources of the diaspora businesses, due to diffrent sources of informatin and experiences as well as multile networks, contributes to business model innovatin in a distictie manner. We investiate the English school market in the Philippines which is established by East Asian diaspora who innovate a business model of conventinal English schools. Two case studies were conducted with Japanese diaspora English schools. Their business is analyzed using a business model canvas (Osterwalder & Pigneur, 2010 and contrasted with the conventinal business model. The empirical cases show that diaspora businesses use knowledge about their country of origin and engage with country of residence and multile networks in diffrent locatins and constellatins to identiy unique opportunitis, leading to a business model innovatin.
Crowdsourcing business model innovation
DEFF Research Database (Denmark)
Waldner, Florian; Poetz, Marion Kristin; Bogers, Marcel
2016-01-01
Successfully adapting existing business models or developing new ones significantly influences a firm’s ability to generate profits and develop competitive advantages. However, business model innovation is perceived as a complex, risky and uncertain process and its success strongly depends on whe...... the perspective of classic strategy making literature, suggest that, at least under certain conditions, crowdsourcing might constitute a promising method to alleviate the process of successful business model innovation.......Successfully adapting existing business models or developing new ones significantly influences a firm’s ability to generate profits and develop competitive advantages. However, business model innovation is perceived as a complex, risky and uncertain process and its success strongly depends...... on whether or not the firm is capable of understanding and addressing their customers’ needs. We conduct a quantitative exploratory case study to investigate how crowdsourcing-based search approaches among user communities can contribute to developing business model innovation. Drawing on data from...
Electricity market modeling trends
Energy Technology Data Exchange (ETDEWEB)
Ventosa, Mariano E-mail: mariano.ventosa@iit.upco.es; Baillo, Alvaro; Ramos, Andres; Rivier, Michel
2005-05-01
The trend towards competition in the electricity sector has led to efforts by the research community to develop decision and analysis support models adapted to the new market context. This paper focuses on electricity generation market modeling. Its aim is to help to identify, classify and characterize the somewhat confusing diversity of approaches that can be found in the technical literature on the subject. The paper presents a survey of the most relevant publications regarding electricity market modeling, identifying three major trends: optimization models, equilibrium models and simulation models. It introduces a classification according to their most relevant attributes. Finally, it identifies the most suitable approaches for conducting various types of planning studies or market analysis in this new context.
Developing mathematical modelling competence
DEFF Research Database (Denmark)
Blomhøj, Morten; Jensen, Tomas Højgaard
2003-01-01
In this paper we introduce the concept of mathematical modelling competence, by which we mean being able to carry through a whole mathematical modelling process in a certain context. Analysing the structure of this process, six sub-competences are identified. Mathematical modelling competence...... cannot be reduced to these six sub-competences, but they are necessary elements in the development of mathematical modelling competence. Experience from the development of a modelling course is used to illustrate how the different nature of the sub-competences can be used as a tool for finding...... the balance between different kinds of activities in a particular educational setting. Obstacles of social, cognitive and affective nature for the students' development of mathematical modelling competence are reported and discussed in relation to the sub-competences....
DEFF Research Database (Denmark)
Borlund, Pia
2003-01-01
of IIR systems as realistically as possible with reference to actual information searching and retrieval processes, though still in a relatively controlled evaluation environment; and 2) to calculate the IIR system performance taking into account the non-binary nature of the assigned relevance......An alternative approach to evaluation of interactive information retrieval (IIR) systems, referred to as the IIR evaluation model, is proposed. The model provides a framework for the collection and analysis of IR interaction data. The aim of the model is two-fold: 1) to facilitate the evaluation...... assessments. The IIR evaluation model is presented as an alternative to the system-driven Cranfield model (Cleverdon, Mills & Keen, 1966; Cleverdon & Keen, 1966) which still is the dominant approach to the evaluation of IR and IIR systems. Key elements of the IIR evaluation model are the use of realistic...
Energy Technology Data Exchange (ETDEWEB)
Mata Dumenjo, Montserrat; Sanchez Navarro, Javier; Casadevall Benet, Vicenc; Gil Cepeda, Javier; Garcia Caballero, Lourdes [Alstom Wind, Barcelona (Spain)
2011-07-01
Several international groups, such as International Electrotechnical Commission (IEC) Electrical Models of Wind Turbines and Wind Farms group, are working to standardize models to be used by TSO's in power system dynamic simulations to analyze the safety of the grid. This paper presents a simple model of generic wind turbine generator, based on REE model and adapted to real machines. To test the model, stability analyses during symmetric three-phase faults have been done. The proposed model can be used to reproduce the behaviour of most of the current wind turbine technologies like DFIG, by tuning its parameters. To do this, it is necessary to collect extensive data series to manage with its high nonlinearity behaviour. (orig.)
Distributed Management Information Models
Fallon, Liam; Keeney, John; van der Meer, Sven
2017-01-01
The formal structure of information models and the controlled manner of accessing and changing such models brings both flexibility and control when managing network elements. However, keeping information models synchronized and consistent across network elements and management systems is a challenging task. Today this problem is exasperated with the advent of ephemeral network functions and elements and also by the need for distributed scalable cooperating management functions running in cont...
Gustman, Alan L.; Thomas Steinmeier
2009-01-01
This paper advances the specification and estimation of models of retirement and saving in two earner families. The complications introduced by the interaction of retirement decisions by husbands and wives have led researchers to adopt a number of simplifications to increase the feasibility of estimating family retirement models. Our model relaxes these restrictions. It includes the extended choice set created when each spouse makes an independent retirement decision. It also includes the ful...
Vibroacoustic Skin Diagnostics Modeling
Directory of Open Access Journals (Sweden)
Svetlana М. Yatsun
2013-01-01
Full Text Available The article deals with the mathematical modeling of biological diagnosis of complex heterogeneous structure (skin, using non-destructive control method. The mathematical model, describing interaction of the material with electrodynamic vibration generator and sensor system, controlling the propagation of small disturbances was developed. The influence of material model parameters on the spectrum in the course of the propagation of the surface disturbance
Energy Technology Data Exchange (ETDEWEB)
Engel, D.W.; McGrail, B.P.
1993-11-01
The Office of Civilian Radioactive Waste Management and the Power Reactor and Nuclear Fuel Development Corporation of Japan (PNC) have supported the development of the Analytical Repository Source-Term (AREST) at Pacific Northwest Laboratory. AREST is a computer model developed to evaluate radionuclide release from an underground geologic repository. The AREST code can be used to calculate/estimate the amount and rate of each radionuclide that is released from the engineered barrier system (EBS) of the repository. The EBS is the man-made or disrupted area of the repository. AREST was designed as a system-level models to simulate the behavior of the total repository by combining process-level models for the release from an individual waste package or container. AREST contains primarily analytical models for calculating the release/transport of radionuclides to the lost rock that surrounds each waste package. Analytical models were used because of the small computational overhead that allows all the input parameters to be derived from a statistical distribution. Recently, a one-dimensional numerical model was also incorporated into AREST, to allow for more detailed modeling of the transport process with arbitrary length decay chains. The next step in modeling the EBS, is to develop a model that couples the probabilistic capabilities of AREST with a more detailed process model. This model will need to look at the reactive coupling of the processes that are involved with the release process. Such coupling would include: (1) the dissolution of the waste form, (2) the geochemical modeling of the groundwater, (3) the corrosion of the container overpacking, and (4) the backfill material, just to name a few. Several of these coupled processes are already incorporated in the current version of AREST.
Modeling multiphase materials processes
Iguchi, Manabu
2010-01-01
""Modeling Multiphase Materials Processes: Gas-Liquid Systems"" describes the methodology and application of physical and mathematical modeling to multi-phase flow phenomena in materials processing. The book focuses on systems involving gas-liquid interaction, the most prevalent in current metallurgical processes. The performance characteristics of these processes are largely dependent on transport phenomena. This volume covers the inherent characteristics that complicate the modeling of transport phenomena in such systems, including complex multiphase structure, intense turbulence, opacity of
Castro Gonzalez, Jorge
2017-01-01
This paper reviews the main modeling techniques for stone columns, both ordinary stone columns and geosynthetic-encased stone columns. The paper tries to encompass the more recent advances and recommendations in the topic. Regarding the geometrical model, the main options are the "unit cell", longitudinal gravel trenches in plane strain conditions, cylindrical rings of gravel in axial symmetry conditions, equivalent homogeneous soil with improved properties and three-dimensional models, eith...
Behavioral Modeling of Memcapacitor
Directory of Open Access Journals (Sweden)
D. Biolek
2011-04-01
Full Text Available Two behavioral models of memcapacitor are developed and implemented in SPICE-compatible simulators. Both models are related to the charge-controlled memcapacitor, the capacitance of which is controlled by the amount of electric charge conveyed through it. The first model starts from the state description of memcapacitor whereas the second one uses the memcapacitor constitutive relation as the only input data. Results of transient analyses clearly show the basic fingerprints of the memcapacitor.
Mangano, M.L.; Aguilar Saavedra, J.A.; Alekhin, S.; Badger, S.; Bauer, C.W.; Becher, T.; Bertone, V.; Bonvini, M.; Boselli, S.; Bothmann, E.; Boughezal, R.; Cacciari, M.; Carloni Calame, C.M.; Caola, F.; Campbell, J.M.; Carrazza, S.; Chiesa, M.; Cieri, L.; Cimaglia, F.; Febres Cordero, F.; Ferrarese, P.; D'Enterria, D.; Ferrera, G.; Garcia i Tormo, X.; Garzelli, M.V.; Germann, E.; Hirschi, V.; Han, T.; Ita, H.; Jäger, B.; Kallweit, S.; Karlberg, A.; Kuttimalai, S.; Krauss, F.; Larkoski, A.J.; Lindert, J.; Luisoni, G.; Maierhöfer, P.; Mattelaer, O.; Martinez, H.; Moch, S.; Montagna, G.; Moretti, M.; Nason, P.; Nicrosini, O.; Oleari, C.; Pagani, D.; Papaefstathiou, A.; Petriello, F.; Piccinini, F.; Pierini, M.; Pierog, T.; Pozzorini, S.; Re, E.; Robens, T.; Rojo, J.; Ruiz, R.; Sakurai, K.; Salam, G.P.; Salfelder, L.; Schönherr, M.; Schulze, M.; Schumann, S.; Selvaggi, M.; Shivaji, A.; Siodmok, A.; Skands, P.; Torrielli, P.; Tramontano, F.; Tsinikos, I.; Tweedie, B.; Vicini, A.; Westhoff, S.; Zaro, M.; Zeppenfeld, D.; CERN. Geneva. ATS Department
2017-06-22
This report summarises the properties of Standard Model processes at the 100 TeV pp collider. We document the production rates and typical distributions for a number of benchmark Standard Model processes, and discuss new dynamical phenomena arising at the highest energies available at this collider. We discuss the intrinsic physics interest in the measurement of these Standard Model processes, as well as their role as backgrounds for New Physics searches.
Tax, Niek; Sidorova, Natalia; Haakma, Reinder; van der Aalst, Wil M.P.
2016-01-01
In this paper we describe a method to discover frequent behavioral patterns in event logs. We express these patterns as \\emph{local process models}. Local process model mining can be positioned in-between process discovery and episode / sequential pattern mining. The technique presented in this paper is able to learn behavioral patterns involving sequential composition, concurrency, choice and loop, like in process mining. However, we do not look at start-to-end models, which distinguishes ou...
Asteroid thermophysical modeling
Delbo, Marco; Mueller, Michael; Emery, Joshua P.; Rozitis, Ben; Capria, Maria Teresa
2015-01-01
The field of asteroid thermophysical modeling has experienced an extraordinary growth in the last ten years, as new thermal infrared data became available for hundreds of thousands of asteroids. The infrared emission of asteroids depends on the body's size, shape, albedo, thermal inertia, roughness and rotational properties. These parameters can therefore be derived by thermophysical modeling of infrared data. Thermophysical modeling led to asteroid size estimates that were confirmed at the f...
2017-03-01
2014 – SEP 2016 4. TITLE AND SUBTITLE PERPETUAL MODEL VALIDATION 5a. CONTRACT NUMBER IN HOUSE –R1AK 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT...Trustworthy architectures for system of systems; Modeling , assessment, and vulnerability analysis; Assessment and measurement for end-to-end system analysis...PERPETUAL MODEL VALIDATION MARCH 2017 FINAL TECHNICAL REPORT APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED STINFO COPY AIR FORCE RESEARCH
Characteristic Time Model Validation
1988-09-01
Characteristic Time Model Validation Final Technical Report .’ ". Tallio, R.C. Prior, Jr., and A. M. Mellor* U.S. Army Research Office Contract...Park, NC 27709-2211 I N I 11, TITLE (Include Securrty Cassification) Characteristic Time Model Validation (unclassified)512 PERSONAL AUTHOR(S) Tallio...number) FIELD GROUP SUB-GROUP Two-dimensional confined shear layers; two-dimensional prefilming airblast atomizers; characteristic time model; finite
Modeling Frequency Comb Sources
Directory of Open Access Journals (Sweden)
Li Feng
2016-06-01
Full Text Available Frequency comb sources have revolutionized metrology and spectroscopy and found applications in many fields. Stable, low-cost, high-quality frequency comb sources are important to these applications. Modeling of the frequency comb sources will help the understanding of the operation mechanism and optimization of the design of such sources. In this paper,we review the theoretical models used and recent progress of the modeling of frequency comb sources.
Heritage Building Information Modelling
Arayici, Y; Mahdjoubi, L.; Counsell, J
2017-01-01
This book is about Heritage Building Information Modelling (HBIM). This is a term that has only begun to be used in the latter part of the last decade, since Building Information Modelling (BIM) superseded 3D digital modelling and computer aided design (CAD) as the term generally used to describe the use of information and communication technology (ICT) for the design, construction, and procurement of the modern built environment. It is sometimes also defined as Historic Building Information ...
Energy Technology Data Exchange (ETDEWEB)
Young, Michael F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2015-07-01
Aerosol particles that deposit on surfaces may be subsequently resuspended by air flowing over the surface. A review of models for this liftoff process is presented and compared to available data. Based on this review, a model that agrees with existing data and is readily computed is presented for incorporation into a system level code such as MELCOR. Liftoff Model for MELCOR July 2015 4 This page is intentionally blank
Energy Technology Data Exchange (ETDEWEB)
Krishna, C. R.
1978-06-01
There has been a spurt of recent activity in developing and applying numerical modeling to combustors and furnaces. The purpose of this review is to provide a brief overview of these recent developments and draw conclusions on the scope for further work in the area of modeling. A brief qualitative review of the various models that have been developed is presented. The models show a progressive recognition of the complexity of turbulence-chemistry interactions and attempts to include more recent submodels of such interactions. There are attempts to incorporate the three-dimensional character of fluid flows and solve the elliptic equations arising in recirculating flows. Flux models of radiation transfer are being included in the energy transport equations. Efficient numerical algorithms are being developd to solve the finite difference form of a set of elliptic, partial differential equations. The test of the success of modeling lies, obviously, in comparison with experimental measurements. Such experiments are being undertaken, but, the techniques of measurements also need development before detailed comparison can be made. The measurements made seem to indicate qualitative agreement of model predictions with limited laboratory measurements. It is concluded from the review that there is still need for development in several areas including turbulence (and turbulence-chemistry interactions) modeling, liquid and solid fuel introduction, interaction with the flow and combustion, models for soot formation, and experimental validation.
Wiegelmann, Thomas; Petrie, Gordon J. D.; Riley, Pete
2017-09-01
Coronal magnetic field models use photospheric field measurements as boundary condition to model the solar corona. We review in this paper the most common model assumptions, starting from MHD-models, magnetohydrostatics, force-free and finally potential field models. Each model in this list is somewhat less complex than the previous one and makes more restrictive assumptions by neglecting physical effects. The magnetohydrostatic approach neglects time-dependent phenomena and plasma flows, the force-free approach neglects additionally the gradient of the plasma pressure and the gravity force. This leads to the assumption of a vanishing Lorentz force and electric currents are parallel (or anti-parallel) to the magnetic field lines. Finally, the potential field approach neglects also these currents. We outline the main assumptions, benefits and limitations of these models both from a theoretical (how realistic are the models?) and a practical viewpoint (which computer resources to we need?). Finally we address the important problem of noisy and inconsistent photospheric boundary conditions and the possibility of using chromospheric and coronal observations to improve the models.
Delocalization in polymer models
Jitomirskaya, S Yu; Stolz, G
2003-01-01
A polymer model is a one-dimensional Schroedinger operator composed of two finite building blocks. If the two associated transfer matrices commute, the corresponding energy is called critical. Such critical energies appear in physical models, an example being the widely studied random dimer model. Although the random models are known to have pure-point spectrum with exponentially localized eigenstates for almost every configuration of the polymers, the spreading of an initially localized wave packet is here proven to be at least diffusive for every configuration.
Izhikevich, Eugene M
2010-11-13
I review a class of hybrid models of neurons that combine continuous spike-generation mechanisms and a discontinuous 'after-spike' reset of state variables. Unlike Hodgkin-Huxley-type conductance-based models, the hybrid spiking models have a few parameters derived from the bifurcation theory; instead of matching neuronal electrophysiology, they match neuronal dynamics. I present a method of after-spike resetting suitable for hardware implementation of such models, and a hybrid numerical method for simulations of large-scale biological spiking networks.
DEFF Research Database (Denmark)
Cameron, Ian T.; Gani, Rafiqul
of process industries. The book builds on the extensive modelling experience of the authors, who have developed models for both research and industrial purposes. It complements existing books by the authors in the modelling area. Those areas include the traditional petroleum and petrochemical industries...... to biotechnology applications, food, polymer and human health application areas. The book highlights to important nature of modern product and process modelling in the decision making processes across the life cycle. As such it provides an important resource for students, researchers and industrial practitioners....
Photovoltaic array performance model.
Energy Technology Data Exchange (ETDEWEB)
Kratochvil, Jay A.; Boyson, William Earl; King, David L.
2004-08-01
This document summarizes the equations and applications associated with the photovoltaic array performance model developed at Sandia National Laboratories over the last twelve years. Electrical, thermal, and optical characteristics for photovoltaic modules are included in the model, and the model is designed to use hourly solar resource and meteorological data. The versatility and accuracy of the model has been validated for flat-plate modules (all technologies) and for concentrator modules, as well as for large arrays of modules. Applications include system design and sizing, 'translation' of field performance measurements to standard reporting conditions, system performance optimization, and real-time comparison of measured versus expected system performance.
Modeling Optical Lithography Physics
Neureuther, Andrew R.; Rubinstein, Juliet; Chin, Eric; Wang, Lynn; Miller, Marshal; Clifford, Chris; Yamazoe, Kenji
2010-06-01
Key physical phenomena associated with resists, illumination, lenses and masks are used to show the progress in models and algorithms for modeling optical projection printing as well as current simulation challenges in managing process complexity for manufacturing. The amazing current capability and challenges for projection printing are discussed using the 22 nm device generation. A fundamental foundation for modeling resist exposure, partial coherent imaging and defect printability is given. The technology innovations of resolution enhancement and chemically amplified resist systems and their modeling challenges are overviewed. Automated chip-level applications in pattern pre-compensation and design-anticipation of residual process variations require new simulation approaches.
DEFF Research Database (Denmark)
Pica, Claudio
2017-01-01
We present new results from our ongoing study of the SU(3) sextet model with two flavors in the two-index symmetric representation of the gauge group. In the simulations use unimproved Wilson fermions to investigate the infrared properties of the model. We have previously presented results...... for the spectrum of the model in the weak coupling regime. Here, to better understand the overall behavior of the lattice model, we map its non-trivial phase structure in the space of bare parameters. At strong coupling, we observe a first order phase transition when decreasing the bare quark mass. This first...
Computer Modeling and Simulation
Energy Technology Data Exchange (ETDEWEB)
Pronskikh, V. S. [Fermilab
2014-05-09
Verification and validation of computer codes and models used in simulation are two aspects of the scientific practice of high importance and have recently been discussed by philosophers of science. While verification is predominantly associated with the correctness of the way a model is represented by a computer code or algorithm, validation more often refers to model’s relation to the real world and its intended use. It has been argued that because complex simulations are generally not transparent to a practitioner, the Duhem problem can arise for verification and validation due to their entanglement; such an entanglement makes it impossible to distinguish whether a coding error or model’s general inadequacy to its target should be blamed in the case of the model failure. I argue that in order to disentangle verification and validation, a clear distinction between computer modeling (construction of mathematical computer models of elementary processes) and simulation (construction of models of composite objects and processes by means of numerical experimenting with them) needs to be made. Holding on to that distinction, I propose to relate verification (based on theoretical strategies such as inferences) to modeling and validation, which shares the common epistemology with experimentation, to simulation. To explain reasons of their intermittent entanglement I propose a weberian ideal-typical model of modeling and simulation as roles in practice. I suggest an approach to alleviate the Duhem problem for verification and validation generally applicable in practice and based on differences in epistemic strategies and scopes
Energy Technology Data Exchange (ETDEWEB)
Brown-VanHoozer, S. A.
1999-06-02
Conscious awareness of our environment is based on a feedback loop comprised of sensory input transmitted to the central nervous system leading to construction of our ''model of the world,'' (Lewis et al, 1982). We then assimilate the neurological model at the unconscious level into information we can later consciously consider useful in identifying belief systems and behaviors for designing diverse systems. Thus, we can avoid potential problems based on our open-to-error perceived reality of the world. By understanding how our model of reality is organized, we allow ourselves to transcend content and develop insight into how effective choices and belief systems are generated through sensory derived processes. These are the processes which provide the designer the ability to meta model (build a model of a model) the user; consequently, matching the mental model of the user with that of the designer's and, coincidentally, forming rapport between the two participants. The information shared between the participants is neither assumed nor generalized, it is closer to equivocal; thus minimizing error through a sharing of each other's model of reality. How to identify individual mental mechanisms or processes, how to organize the individual strategies of these mechanisms into useful patterns, and to formulate these into models for success and knowledge based outcomes is the subject of the discussion that follows.
Multifamily Envelope Leakage Model
Energy Technology Data Exchange (ETDEWEB)
Faakye, O. [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Griffiths, D. [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)
2015-05-01
The objective of the 2013 research project was to develop the model for predicting fully guarded test results (FGT), using unguarded test data and specific building features of apartment units. The model developed has a coefficient of determination R2 value of 0.53 with a root mean square error (RMSE) of 0.13. Both statistical metrics indicate that the model is relatively strong. When tested against data that was not included in the development of the model, prediction accuracy was within 19%, which is reasonable given that seasonal differences in blower door measurements can vary by as much as 25%.
Faraway, Julian J
2014-01-01
A Hands-On Way to Learning Data AnalysisPart of the core of statistics, linear models are used to make predictions and explain the relationship between the response and the predictors. Understanding linear models is crucial to a broader competence in the practice of statistics. Linear Models with R, Second Edition explains how to use linear models in physical science, engineering, social science, and business applications. The book incorporates several improvements that reflect how the world of R has greatly expanded since the publication of the first edition.New to the Second EditionReorganiz
Højsgaard, Søren; Lauritzen, Steffen
2012-01-01
Graphical models in their modern form have been around since the late 1970s and appear today in many areas of the sciences. Along with the ongoing developments of graphical models, a number of different graphical modeling software programs have been written over the years. In recent years many of these software developments have taken place within the R community, either in the form of new packages or by providing an R interface to existing software. This book attempts to give the reader a gentle introduction to graphical modeling using R and the main features of some of these packages. In add
Levy, R.; Mcginness, H.
1976-01-01
Investigations were performed to predict the power available from the wind at the Goldstone, California, antenna site complex. The background for power prediction was derived from a statistical evaluation of available wind speed data records at this location and at nearby locations similarly situated within the Mojave desert. In addition to a model for power prediction over relatively long periods of time, an interim simulation model that produces sample wind speeds is described. The interim model furnishes uncorrelated sample speeds at hourly intervals that reproduce the statistical wind distribution at Goldstone. A stochastic simulation model to provide speed samples representative of both the statistical speed distributions and correlations is also discussed.
Belegradek, OV
1999-01-01
This volume is a collection of papers on model theory and its applications. The longest paper, "Model Theory of Unitriangular Groups" by O. V. Belegradek, forms a subtle general theory behind Mal‴tsev's famous correspondence between rings and groups. This is the first published paper on the topic. Given the present model-theoretic interest in algebraic groups, Belegradek's work is of particular interest to logicians and algebraists. The rest of the collection consists of papers on various questions of model theory, mainly on stability theory. Contributors are leading Russian researchers in the
Tanwir, Savera
2014-01-01
There has been a phenomenal growth in video applications over the past few years. An accurate traffic model of Variable Bit Rate (VBR) video is necessary for performance evaluation of a network design and for generating synthetic traffic that can be used for benchmarking a network. A large number of models for VBR video traffic have been proposed in the literature for different types of video in the past 20 years. Here, the authors have classified and surveyed these models and have also evaluated the models for H.264 AVC and MVC encoded video and discussed their findings.
DEFF Research Database (Denmark)
Könemann, Patrick
2009-01-01
is fundamentally different. This paper reports on our ongoing work on model-independent diffs, i.e. a diff that does not directly refer to the models it was created from. Based on that, we present an idea of how the diff could be generalized, e.g. many atomic diffs are merged to a new, generalized diff. One use...... of these concepts could be a patch for models as it already exists for text files. The advantage of such a generalized diff compared to dasianormalpsila diffs is that it is applicable to a higher variety of models....
Energy Technology Data Exchange (ETDEWEB)
Valgas, Helio Moreira; Pinto, Roberto del Giudice R.; Franca, Carlos [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Lambert-Torres, Germano; Silva, Alexandre P. Alves da; Pires, Robson Celso; Costa Junior, Roberto Affonso [Escola Federal de Engenharia de Itajuba, MG (Brazil)
1994-12-31
Accurate dynamic load models allow more precise calculations of power system controls and stability limits, which are critical mainly in the operation planning of power systems. This paper describes the development of a computer program (software) for static and dynamic load model studies using the measurement approach for the CEMIG system. Two dynamic load model structures are developed and tested. A procedure for applying a set of measured data from an on-line transient recording system to develop load models is described. (author) 6 refs., 17 figs.
Robichaud-Ekstrand, S; Vandal, S; Viens, C; Bradet, R
2001-03-01
One of the challenges for health professionals is to understand how individuals adopt and maintain healthy behaviours that lead to a better quality of life. This review of health behaviour models will help nurses determine appropriate interventions, and enhance programs that promote health and prevent sickness in individuals or groups of individuals. In order to establish priorities and to prevent omitting important points in planning such health programs, many theoretical and conceptual models have attempted to explain health behaviours as well as the indicators of compliance. The purpose of this article is to summarise the most utilised health behaviour models, to offer a schematic representation, and to explain the advantages and disadvantages of each model. Until now, no article had reviewed these models into the same work. This article will be of assistance to nurse researchers and clinicians working in health prevention, who are interested in choosing a health behaviour model to plan a scientific research, or to develop a clinical program. The models are presented according to the following classifications: cognitive value expectation; theories of personality; communication theories; models of program planning; and models of integration.
Alves, Daniele S M; McCullough, Matthew; Weiner, Neal
2016-01-01
Models with Dirac gauginos provide appealing scenarios for physics beyond the standard model. They have smaller radiative corrections to the Higgs mass, a suppression of certain SUSY production processes, and ameliorated flavor constraints. Unfortunately, they also generally have tachyons, the solutions to which typically spoil these positive features. The recently proposed "Goldstone Gaugino" mechanism provides a simple solution that eliminates these tachyonic states. We provide details on this mechanism and explore models for its origin. In particular, we find SUSY QCD models that realize this idea simply, and discuss scenarios for unification.
Dynamic modelling of windmills
DEFF Research Database (Denmark)
Akhmatov, Vladislav; Knudsen, Hans
1999-01-01
An empirical dynamic model of windmills is set up based on analysis of measured Fourier spectra of the active electric power from a wind farm. The model is based on the assumption that eigenswings of the mechanical construction of the windmills excited by the phenomenon of vortex tower interaction...... will be transferred through the shaft to the electrical generator and result in disturbances of the active electric power supplied by the windmills. The results of the model are found to be in agreement with measurements in the frequency range of the model that is from 0.1 to 10 Hz....
Croatian Cadastre Database Modelling
Directory of Open Access Journals (Sweden)
Zvonko Biljecki
2013-04-01
Full Text Available The Cadastral Data Model has been developed as a part of a larger programme to improve products and production environment of the Croatian Cadastral Service of the State Geodetic Administration (SGA. The goal of the project was to create a cadastral data model conforming to relevant standards and specifications in the field of geoinformation (GI adapted by international organisations for standardisation under the competence of GI (ISO TC211 and OpenGIS and it implementations.The main guidelines during the project have been object-oriented conceptual modelling of the updated users' requests and a "new" cadastral data model designed by SGA - Faculty of Geodesy - Geofoto LLC project team. The UML of the conceptual model is given per all feature categories and is described only at class level. The next step was the UML technical model, which was developed from the UML conceptual model. The technical model integrates different UML schemas in one united schema.XML (eXtensible Markup Language was applied for XML description of UML models, and then the XML schema was transferred into GML (Geography Markup Language application schema. With this procedure we have completely described the behaviour of each cadastral feature and rules for the transfer and storage of cadastral features into the database.
SME International Business Models
DEFF Research Database (Denmark)
Child, John; Hsieh, Linda; Elbanna, Said
2017-01-01
models that SMEs follow? Three distinct international business models (traditional market-adaptive, technology exploiter, and ambidextrous explorer) are found among the SMEs studied. The likelihood of SMEs adopting one business model rather than another is to a high degree predictable with reference......This paper addresses two questions through a study of 180 SMEs located in contrasting industry and home country contexts. First, which business models for international markets prevail among SMEs and do they configure into different types? Second, which factors predict the international business...... to a small set of factors: industry, level of home economy development, and decision-maker international experience....
Plasticity: modeling & computation
National Research Council Canada - National Science Library
Borja, Ronaldo Israel
2013-01-01
.... "Plasticity Modeling & Computation" is a textbook written specifically for students who want to learn the theoretical, mathematical, and computational aspects of inelastic deformation in solids...
A Revised Communication Model.
Emmons, John H.
1988-01-01
Presents a communication process model that distinguishes between active and passsive communication. Discusses the various stages in communication, including pretransmission, transmission, and posttransmission. (CH)
DEFF Research Database (Denmark)
Gudiksen, Sune Klok; Poulsen, Søren Bolvig; Buur, Jacob
2014-01-01
, the modelling approaches proposed still rely on linear, rational conceptions and causal reasoning. Through six business cases we argue that participatory design has a role to play, and indeed, can lead the way into another approach to business modelling, which we call business model making. The paper...... illustrates how the application of participatory business model design toolsets can open up discussions on alternative scenarios through improvisation, mock-up making and design game playing, before qualitative judgment on the most promising scenario is carried out....
Energy Technology Data Exchange (ETDEWEB)
Ahmed E. Hassan
2006-01-24
Models have an inherent uncertainty. The difficulty in fully characterizing the subsurface environment makes uncertainty an integral component of groundwater flow and transport models, which dictates the need for continuous monitoring and improvement. Building and sustaining confidence in closure decisions and monitoring networks based on models of subsurface conditions require developing confidence in the models through an iterative process. The definition of model validation is postulated as a confidence building and long-term iterative process (Hassan, 2004a). Model validation should be viewed as a process not an end result. Following Hassan (2004b), an approach is proposed for the validation process of stochastic groundwater models. The approach is briefly summarized herein and detailed analyses of acceptance criteria for stochastic realizations and of using validation data to reduce input parameter uncertainty are presented and applied to two case studies. During the validation process for stochastic models, a question arises as to the sufficiency of the number of acceptable model realizations (in terms of conformity with validation data). Using a hierarchical approach to make this determination is proposed. This approach is based on computing five measures or metrics and following a decision tree to determine if a sufficient number of realizations attain satisfactory scores regarding how they represent the field data used for calibration (old) and used for validation (new). The first two of these measures are applied to hypothetical scenarios using the first case study and assuming field data consistent with the model or significantly different from the model results. In both cases it is shown how the two measures would lead to the appropriate decision about the model performance. Standard statistical tests are used to evaluate these measures with the results indicating they are appropriate measures for evaluating model realizations. The use of validation
Magretta, Joan
2002-05-01
"Business model" was one of the great buzz-words of the Internet boom. A company didn't need a strategy, a special competence, or even any customers--all it needed was a Web-based business model that promised wild profits in some distant, ill-defined future. Many people--investors, entrepreneurs, and executives alike--fell for the fantasy and got burned. And as the inevitable counterreaction played out, the concept of the business model fell out of fashion nearly as quickly as the .com appendage itself. That's a shame. As Joan Magretta explains, a good business model remains essential to every successful organization, whether it's a new venture or an established player. To help managers apply the concept successfully, she defines what a business model is and how it complements a smart competitive strategy. Business models are, at heart, stories that explain how enterprises work. Like a good story, a robust business model contains precisely delineated characters, plausible motivations, and a plot that turns on an insight about value. It answers certain questions: Who is the customer? How do we make money? What underlying economic logic explains how we can deliver value to customers at an appropriate cost? Every viable organization is built on a sound business model, but a business model isn't a strategy, even though many people use the terms interchangeably. Business models describe, as a system, how the pieces of a business fit together. But they don't factor in one critical dimension of performance: competition. That's the job of strategy. Illustrated with examples from companies like American Express, EuroDisney, WalMart, and Dell Computer, this article clarifies the concepts of business models and strategy, which are fundamental to every company's performance.
Biosphere Process Model Report
Energy Technology Data Exchange (ETDEWEB)
J. Schmitt
2000-05-25
To evaluate the postclosure performance of a potential monitored geologic repository at Yucca Mountain, a Total System Performance Assessment (TSPA) will be conducted. Nine Process Model Reports (PMRs), including this document, are being developed to summarize the technical basis for each of the process models supporting the TSPA model. These reports cover the following areas: (1) Integrated Site Model; (2) Unsaturated Zone Flow and Transport; (3) Near Field Environment; (4) Engineered Barrier System Degradation, Flow, and Transport; (5) Waste Package Degradation; (6) Waste Form Degradation; (7) Saturated Zone Flow and Transport; (8) Biosphere; and (9) Disruptive Events. Analysis/Model Reports (AMRs) contain the more detailed technical information used to support TSPA and the PMRs. The AMRs consists of data, analyses, models, software, and supporting documentation that will be used to defend the applicability of each process model for evaluating the postclosure performance of the potential Yucca Mountain repository system. This documentation will ensure the traceability of information from its source through its ultimate use in the TSPA-Site Recommendation (SR) and in the National Environmental Policy Act (NEPA) analysis processes. The objective of the Biosphere PMR is to summarize (1) the development of the biosphere model, and (2) the Biosphere Dose Conversion Factors (BDCFs) developed for use in TSPA. The Biosphere PMR does not present or summarize estimates of potential radiation doses to human receptors. Dose calculations are performed as part of TSPA and will be presented in the TSPA documentation. The biosphere model is a component of the process to evaluate postclosure repository performance and regulatory compliance for a potential monitored geologic repository at Yucca Mountain, Nevada. The biosphere model describes those exposure pathways in the biosphere by which radionuclides released from a potential repository could reach a human receptor
Comparing root architectural models
Schnepf, Andrea; Javaux, Mathieu; Vanderborght, Jan
2017-04-01
Plant roots play an important role in several soil processes (Gregory 2006). Root architecture development determines the sites in soil where roots provide input of carbon and energy and take up water and solutes. However, root architecture is difficult to determine experimentally when grown in opaque soil. Thus, root architectural models have been widely used and been further developed into functional-structural models that are able to simulate the fate of water and solutes in the soil-root system (Dunbabin et al. 2013). Still, a systematic comparison of the different root architectural models is missing. In this work, we focus on discrete root architecture models where roots are described by connected line segments. These models differ (a) in their model concepts, such as the description of distance between branches based on a prescribed distance (inter-nodal distance) or based on a prescribed time interval. Furthermore, these models differ (b) in the implementation of the same concept, such as the time step size, the spatial discretization along the root axes or the way stochasticity of parameters such as root growth direction, growth rate, branch spacing, branching angles are treated. Based on the example of two such different root models, the root growth module of R-SWMS and RootBox, we show the impact of these differences on simulated root architecture and aggregated information computed from this detailed simulation results, taking into account the stochastic nature of those models. References Dunbabin, V.M., Postma, J.A., Schnepf, A., Pagès, L., Javaux, M., Wu, L., Leitner, D., Chen, Y.L., Rengel, Z., Diggle, A.J. Modelling root-soil interactions using three-dimensional models of root growth, architecture and function (2013) Plant and Soil, 372 (1-2), pp. 93 - 124. Gregory (2006) Roots, rhizosphere and soil: the route to a better understanding of soil science? European Journal of Soil Science 57: 2-12.
Existing Model Metrics and Relations to Model Quality
Mohagheghi, Parastoo; Dehlen, Vegard
2009-01-01
This paper presents quality goals for models and provides a state-of-the-art analysis regarding model metrics. While model-based software development often requires assessing the quality of models at different abstraction and precision levels and developed for multiple purposes, existing work on model metrics do not reflect this need. Model size metrics are descriptive and may be used for comparing models but their relation to model quality is not welldefined. Code metrics are proposed to be ...
Proactive Quality Guidance for Model Evolution in Model Libraries
Ganser, Andreas; Lichter, Horst; Roth, Alexander; Rumpe, Bernhard
2014-01-01
Model evolution in model libraries differs from general model evolution. It limits the scope to the manageable and allows to develop clear concepts, approaches, solutions, and methodologies. Looking at model quality in evolving model libraries, we focus on quality concerns related to reusability. In this paper, we put forward our proactive quality guidance approach for model evolution in model libraries. It uses an editing-time assessment linked to a lightweight quality model, corresponding m...
Spiral model pilot project information model
1991-01-01
The objective was an evaluation of the Spiral Model (SM) development approach to allow NASA Marshall to develop an experience base of that software management methodology. A discussion is presented of the Information Model (IM) that was used as part of the SM methodology. A key concept of the SM is the establishment of an IM to be used by management to track the progress of a project. The IM is the set of metrics that is to be measured and reported throughout the life of the project. These metrics measure both the product and the process to ensure the quality of the final delivery item and to ensure the project met programmatic guidelines. The beauty of the SM, along with the IM, is the ability to measure not only the correctness of the specification and implementation of the requirements but to also obtain a measure of customer satisfaction.
Multiple Model Approaches to Modelling and Control,
DEFF Research Database (Denmark)
on the ease with which prior knowledge can be incorporated. It is interesting to note that researchers in Control Theory, Neural Networks,Statistics, Artificial Intelligence and Fuzzy Logic have more or less independently developed very similar modelling methods, calling them Local ModelNetworks, Operating......, and allows direct incorporation of high-level and qualitative plant knowledge into themodel. These advantages have proven to be very appealing for industrial applications, and the practical, intuitively appealing nature of the framework isdemonstrated in chapters describing applications of local methods...... to problems in the process industries, biomedical applications and autonomoussystems. The successful application of the ideas to demanding problems is already encouraging, but creative development of the basic framework isneeded to better allow the integration of human knowledge with automated learning...
Modelling pediatric kinematics
Ratingen, M.R. van; Wismans, J.S.H.M.
1998-01-01
In the field of pediatric biomechanics, crash dumy and numerical model development suffers from to limited human subject data to directly establish response and injury values. In order to create child crash dummies and numerical models, it is necessary to combine the results from real world accident
Samberg, Laura, Comp.; Sheeran, Melyssa, Comp.
This booklet contains profiles of 26 community-school models. Although communities and states approach the development of community schools in various ways, all the models presented here reflect the shared vision of the Coalition for Community Schools, that is, a set of partnerships to establish a place where services, support, and opportunity…
MODEL PREDICTIVE CONTROL FUNDAMENTALS
African Journals Online (AJOL)
2012-07-02
Jul 2, 2012 ... written to simulate an example of a randomly generated system. This paper can serve as tutorial to anyone interested in this area of research. Keywords: model predictive control, linear systems, discrete-time systems, constraints, quadratic programming. 1. Introduction. Model Predictive Control (MPC), also ...
Modeling volcanic ash dispersal
CERN. Geneva
2010-01-01
The assessment of volcanic fallout hazard is an important scientific, economic, and political issue, especially in densely populated areas. From a scientific point of view, considerable progress has been made during the last two decades through the use of increasingly powerful computational models and capabilities. Nowadays, models are used to quantify hazard...
Modelling river dune development
Paarlberg, Andries; Weerts, H.J.T.; Dohmen-Janssen, Catarine M.; Ritsema, I.L; Hulscher, Suzanne J.M.H.; van Os, A.G.; Termes, A.P.P.
2005-01-01
Since river dunes influence flow resistance, predictions of dune dimensions are required to make accurate water level predictions. A model approach to simulate developing river dunes is presented. The model is set-up to be appropriate, i.e. as simple as possible, but with sufficient accuracy for
Computational human body models
Wismans, J.S.H.M.; Happee, R.; Dommelen, J.A.W. van
2005-01-01
Computational human body models are widely used for automotive crashsafety research and design and as such have significantly contributed to a reduction of traffic injuries and fatalities. Currently crash simulations are mainly performed using models based on crash-dummies. However crash dummies
Knezovich, F. M.
1976-01-01
A modular structured system of computer programs is presented utilizing earth and ocean dynamical data keyed to finitely defined parameters. The model is an assemblage of mathematical algorithms with an inherent capability of maturation with progressive improvements in observational data frequencies, accuracies and scopes. The Eom in its present state is a first-order approach to a geophysical model of the earth's dynamics.
Buggey, Tom; Ogle, Lindsey
2012-01-01
Video self-modeling (VSM) first appeared on the psychology and education stage in the early 1970s. The practical applications of VSM were limited by lack of access to tools for editing video, which is necessary for almost all self-modeling videos. Thus, VSM remained in the research domain until the advent of camcorders and VCR/DVD players and,…
2014-08-01
CENTURY is a computer model of plant-soil ecosystems that simulates the dynamics of grasslands, forest , crops, and savannas with a focus on nutri...Kamnalrut, and J. L. Kinyamario. 1993. Observations and modeling of biomass and soil organic matter dynamics for the grassland biome worldwide. Global
MEDIATION AGREEMENTS LEGAL MODEL
Directory of Open Access Journals (Sweden)
Alexander Ponomarev
2015-07-01
Full Text Available This article focuses on the legal model of mediation agreements in Russian and international legislation. The authors consider the main provisions of the mediation agreements in civil matters, in particular, is defined by such features of the legal model as the requirements for this type of agreements. In addition, the article discusses the problematic issues of implementation of mediation agreements.
U.S. Environmental Protection Agency — QUAL2K (or Q2K) is a river and stream water quality model that is intended to represent a modernized version of the QUAL2E (or Q2E) model (Brown and Barnwell 1987).
Business model innovation paths
Chesbrough, H.; Di Minin, Alberto; Piccaluga, A.
2013-01-01
This chapter explains the business model concept and explores the reasons why “innovation” and “innovation in services” are no longer exclusively a technological issue. Rather, we highlight that business models are critical components at the centre of business innovation processes. We also attempt
African Journals Online (AJOL)
zlukovi
modelled as a quadratic regression, nested within parity. The previous lactation length was ... This proportion was mainly covered by linear and quadratic coefficients. Results suggest that RRM could .... The multiple trait models in scalar notation are presented by equations (1, 2), while equation. (3) represents the random ...
Wavelet Enhanced Appearance Modelling
DEFF Research Database (Denmark)
Stegmann, Mikkel Bille; Forchhammer, Søren; Cootes, Timothy F.
2004-01-01
Generative segmentation methods such as the Active Appearance Models (AAM) establish dense correspondences by modelling variation of shape and pixel intensities. Alas, for 3D and high-resolution 2D images typical in medical imaging, this approach is rendered infeasible due to excessive storage...
SWMM is a model for urban hydrology. It has a long history and is relied upon by professional engineers in the US and around the world. SWMM provides both gray and green Infrastructure modeling capabilities. As such, it is a convenient tool for understanding the tradeoff between ...
Response model parameter linking
Barrett, M.L.D.
2015-01-01
With a few exceptions, the problem of linking item response model parameters from different item calibrations has been conceptualized as an instance of the problem of equating observed scores on different test forms. This thesis argues, however, that the use of item response models does not require
AUTHOR|(CDS)2069934
2014-01-01
Recent LHC highlights of searches for Higgs bosons beyond the Standard Model are presented. The results by the ATLAS and CMS collaborations are based on 2011 and 2012 proton-proton collision data at centre-of-mass energies of 7 and 8 TeV, respectively. They test a wide range of theoretical models.
Business Model Innovation Leadership
DEFF Research Database (Denmark)
Lindgren, Peter
2012-01-01
When SME´s practice business model (BM) innovation (BMI), leading strategically BMs through the innovation process can be the difference between success and failure to a BM. Business Model Innovation Leadership (BMIL) is however extremely complex to carry out especially to small and medium size...... these 5) SME´s is generally in lack of BMIL skills....
DEFF Research Database (Denmark)
Franco de los Rios, Camilo Andres; Hougaard, Jens Leth; Nielsen, Kurt
This paper extends the Weighted Overlap Dominance (WOD) model (initially presented in J.L. Hougaard, K. Nielsen. Weighted Overlap Dominance - A procedure for interactive selection on multidimensional interval data. Applied Mathematical Modelling 35, 2011, 3958 - 3969), as an outranking approach...
Synkronmaskinens matematiske model
DEFF Research Database (Denmark)
Leisner, Torben
1999-01-01
Beskrivelse af synkronmaskinens matematiske model ud fra transformation af fasestrømme til aksestrømme med bibeholdelse af de fysiske egenskaber.......Beskrivelse af synkronmaskinens matematiske model ud fra transformation af fasestrømme til aksestrømme med bibeholdelse af de fysiske egenskaber....
DEFF Research Database (Denmark)
Olesen, H. R.
1998-01-01
Proceedings of the Twenty-Second NATO/CCMS International Technical Meeting on Air Pollution Modeling and Its Application, held June 6-10, 1997, in Clermont-Ferrand, France.......Proceedings of the Twenty-Second NATO/CCMS International Technical Meeting on Air Pollution Modeling and Its Application, held June 6-10, 1997, in Clermont-Ferrand, France....
Modelling Retail Floorspace Productivity
A.R. Thurik (Roy); P. Kooiman
1986-01-01
textabstractThis research note presents a "switching regime" model to investigate the impact of environmental factors on floorspace productivity of individual retail stores. The model includes independent supply and demand functions, which are incorporated within a sales maximizing framework. Unlike
Multilevel Mixture Factor Models
Varriale, Roberta; Vermunt, Jeroen K.
2012-01-01
Factor analysis is a statistical method for describing the associations among sets of observed variables in terms of a small number of underlying continuous latent variables. Various authors have proposed multilevel extensions of the factor model for the analysis of data sets with a hierarchical structure. These Multilevel Factor Models (MFMs)…
A Situational Maintenance Model
DEFF Research Database (Denmark)
Luxhoj, James T.; Thorsteinsson, Uffe; Riis, Jens Ove
1997-01-01
An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance.......An overview of trend in maintenance management and presentation of a situational model and an analytical tools for identification of managerial efforts in maintenance....
Archaeological predictive model set.
2015-03-01
This report is the documentation for Task 7 of the Statewide Archaeological Predictive Model Set. The goal of this project is to : develop a set of statewide predictive models to assist the planning of transportation projects. PennDOT is developing t...
Slats, P.A.; Bhola, B.; Evers, J.J.M.; Dijkhuizen, G.
1995-01-01
Logistic chain modelling is very important in improving the overall performance of the total logistic chain. Logistic models provide support for a large range of applications, such as analysing bottlenecks, improving customer service, configuring new logistic chains and adapting existing chains to
DEFF Research Database (Denmark)
Beauquier, Maxime; Schürmann, Carsten
2011-01-01
In this paper, we present a model based on relations for bigraphical reactive system [Milner09]. Its defining characteristics are that validity and reaction relations are captured as traces in a multi-set rewriting system. The relational model is derived from Milner's graphical definition...
Parks, Melissa
2014-01-01
Model-eliciting activities (MEAs) are not new to those in engineering or mathematics, but they were new to Melissa Parks. Model-eliciting activities are simulated real-world problems that integrate engineering, mathematical, and scientific thinking as students find solutions for specific scenarios. During this process, students generate solutions…
Debating complexity in modeling
Hunt, Randall J.; Zheng, Chunmiao
1999-01-01
Complexity in modeling would seem to be an issue of universal importance throughout the geosciences, perhaps throughout all science, if the debate last year among groundwater modelers is any indication. During the discussion the following questions and observations made up the heart of the debate.
Strategic Leadership Development Model
2012-03-19
Strategic Leadership Development Model by Brigadier Farhat Abbas Sani Pakistan Army United States Army War College...Strategic Leadership Development Model 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Brigadier...Stephen J Gerras AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Department of Command Leadership and Management
African Journals Online (AJOL)
LUCY
Algorithm and flow chart based on kinetic model were used for developing the Visual Basic code, ASP-. SIM. The code ... wastewater treatment using kinetic models ... Soluble Chemical oxygen demand. rbCOD. Readily biodegradable Chemical oxygen demand. TKN. Total Kjeldahl nitrogen. NH4-N. Ammonia nitrogen. TSS.
Directory of Open Access Journals (Sweden)
R.I. Parovik
2012-06-01
Full Text Available In a model of radioactive decay of radon in the sample (222Rn. The model assumes that the probability of the decay of radon and its half-life depends on the fractal properties of the geological environment. The dependencies of the decay parameters of the fractal dimension of the medium.
Thornburgh, William R.; Tretter, Thomas R.
2017-01-01
This article describes a unit in which students investigate total solar eclipses, such as the one coming August 21, from several perspectives. It incorporates mathematical thinking and aligns with the "Next Generation Science Standard." This article refers to physical, virtual, and mathematical modeling. Various models and perspectives…
Ifenthaler, Dirk; Seel, Norbert M.
2013-01-01
In this paper, there will be a particular focus on mental models and their application to inductive reasoning within the realm of instruction. A basic assumption of this study is the observation that the construction of mental models and related reasoning is a slowly developing capability of cognitive systems that emerges effectively with proper…
Models for Dynamic Applications
DEFF Research Database (Denmark)
Sales-Cruz, Mauricio; Morales Rodriguez, Ricardo; Heitzig, Martina
2011-01-01
This chapter covers aspects of the dynamic modelling and simulation of several complex operations that include a controlled blending tank, a direct methanol fuel cell that incorporates a multiscale model, a fluidised bed reactor, a standard chemical reactor and finally a polymerisation reactor. T...
Structural Equation Model Trees
Brandmaier, Andreas M.; von Oertzen, Timo; McArdle, John J.; Lindenberger, Ulman
2013-01-01
In the behavioral and social sciences, structural equation models (SEMs) have become widely accepted as a modeling tool for the relation between latent and observed variables. SEMs can be seen as a unification of several multivariate analysis techniques. SEM Trees combine the strengths of SEMs and the decision tree paradigm by building tree…
DEFF Research Database (Denmark)
Tamke, Martin
2015-01-01
Appearing almost alive, a novel set of computational design models can become an active counterpart for architects in the design process. The ability to loop, sense and query and the integration of near real-time simulation provide these models with a depth and agility that allows for instant...
Butenas, S.; van 't Veer, C.; Cawthern, K.; Brummel, K. E.; Mann, K. G.
2000-01-01
We have used three models to study the process of tissue factor-initiated blood coagulation. These are: synthetic 'plasma' mixtures prepared with the proteins and membranes involved in the reaction and its regulation; mathematical models based on the reaction kinetics, binding constants and
Ionospheric modelling for navigation
Aragon Angel, M. A.
Signals transmitted to and from satellites for communication and navigation purposes must pass through the ionosphere Ionospheric irregularities most common at equatorial latitudes although they could occur anywhere can have a major impact on system performance and reliability and commercial navigation service satellite-based providers need to account for their effects For a GNSS single-frequency receiver the Slant Total Electron Content STEC must be known by the user through broadcast corrections In this context there are several sets of broadcast parameters that can be defined to take into account this ionospheric term The chosen model to generate the ionospheric correction coefficients for the present study is the NeQuick model although with a number of adaptations intended to improve effective ionospheric effect modelling performances The aim of this study is to describe a possible adaptation to the NeQuick model for real time purposes and suitable for single frequency users Therefore it will be necessary to determine the performance of this modified NeQuick model in correcting the ionospheric delay In order to generate the ionospheric corrections for single frequency receivers using the NeQuick model a certain approach should be followed to adapt the performance of NeQuick since this model was originally developed to provide TEC using averaged monthly information of the solar activity and not daily one Thus to use NeQuick for real time applications as an ionospheric broadcasted model such as Klobuchar solar daily information at the user point
Clancy, Cornelius J; Cheng, Shaoji; Nguyen, Minh Hong
2009-01-01
Animal models are powerful tools to study the pathogenesis of diverse types of candidiasis. Murine models are particularly attractive because of cost, ease of handling, technical feasibility, and experience with their use. In this chapter, we describe methods for two of the most popular murine models of disease caused by Candida albicans. In an intravenously disseminated candidiasis (DC) model, immunocompetent mice are infected by lateral tail vein injections of a C. albicans suspension. Endpoints include mortality, tissue burdens of infection (most importantly in the kidneys, although spleens and livers are sometimes also assessed), and histopathology of infected organs. In a model of oral/esophageal candidiasis, mice are immunosuppressed with cortisone acetate and inoculated in the oral cavities using swabs saturated with a C. albicans suspension. Since mice do not die from oral candidiasis in this model, endpoints are tissue burden of infection and histopathology. The DC and oral/esophageal models are most commonly used for studies of C. albicans virulence, in which the disease-causing ability of a mutant strain is compared with an isogenic parent strain. Nevertheless, the basic techniques we describe are also applicable to models adapted to investigate other aspects of pathogenesis, such as spatiotemporal patterns of gene expression, specific aspects of host immune response and assessment of antifungal agents, immunomodulatory strategies, and vaccines.
Entrepreneurship and Role Models
N. Bosma (Niels); S.J.A. Hessels (Jolanda); V. Schutjens (Veronique); M. van Praag (Mirjam); I. Verheul (Ingrid)
2011-01-01
textabstractIn the media role models are increasingly being acknowledged as an influential factor in explaining the reasons for the choice of occupation and career. Various conceptual studies have proposed links between role models and entrepreneurial intentions. However, empirical research aimed at
Stochastic Control - External Models
DEFF Research Database (Denmark)
Poulsen, Niels Kjølstad
2005-01-01
This note is devoted to control of stochastic systems described in discrete time. We are concerned with external descriptions or transfer function model, where we have a dynamic model for the input output relation only (i.e.. no direct internal information). The methods are based on LTI systems...... a section on that topic can be found in appendix....
Adaptability of model transformations
Ivanov, Ivan
2005-01-01
Model Driven Engineering (MDE) is an emerging approach for software development. This thesis focuses on one of the main research topics in MDE: transforming models. This topic may be studied from process and artifact perspectives. The artifact perspective involves transformation definitions and
Composite Load Model Evaluation
Energy Technology Data Exchange (ETDEWEB)
Lu, Ning; Qiao, Hong (Amy)
2007-09-30
The WECC load modeling task force has dedicated its effort in the past few years to develop a composite load model that can represent behaviors of different end-user components. The modeling structure of the composite load model is recommended by the WECC load modeling task force. GE Energy has implemented this composite load model with a new function CMPLDW in its power system simulation software package, PSLF. For the last several years, Bonneville Power Administration (BPA) has taken the lead and collaborated with GE Energy to develop the new composite load model. Pacific Northwest National Laboratory (PNNL) and BPA joint force and conducted the evaluation of the CMPLDW and test its parameter settings to make sure that: • the model initializes properly, • all the parameter settings are functioning, and • the simulation results are as expected. The PNNL effort focused on testing the CMPLDW in a 4-bus system. An exhaustive testing on each parameter setting has been performed to guarantee each setting works. This report is a summary of the PNNL testing results and conclusions.
Caldwell, Robert R.
2013-08-01
These lectures present an introduction to dark energy cosmology. We begin with a review of the Standard Cosmological Model, in which the accelerated cosmic expansion is due to a cosmological constant. We then turn to models of quintessence, a light cosmic scalar field, and explore the particle physics origins and cosmological behavior.
Veldhoven, J. van; Riet, M.W.G. van; Dol, H.S.; Mohamoud, A.A.; Keus, D.; Beckers, A.L.D.
2009-01-01
In the field of mine laying and of mine countermeasures, understanding of the actuation behaviour of influence mines is of vital importance. Modelling can enhance such understanding. In this paper, a flexible generic mine model is presented that allows the user to easily generate different computer
Energy Technology Data Exchange (ETDEWEB)
Jacob J. Jacobson; Gretchen Matthern
2007-04-01
System Dynamics is a computer-aided approach to evaluating the interrelationships of different components and activities within complex systems. Recently, System Dynamics models have been developed in areas such as policy design, biological and medical modeling, energy and the environmental analysis, and in various other areas in the natural and social sciences. The real power of System Dynamic modeling is gaining insights into total system behavior as time, and system parameters are adjusted and the effects are visualized in real time. System Dynamic models allow decision makers and stakeholders to explore long-term behavior and performance of complex systems, especially in the context of dynamic processes and changing scenarios without having to wait decades to obtain field data or risk failure if a poor management or design approach is used. The Idaho National Laboratory recently has been developing a System Dynamic model of the US Nuclear Fuel Cycle. The model is intended to be used to identify and understand interactions throughout the entire nuclear fuel cycle and suggest sustainable development strategies. This paper describes the basic framework of the current model and presents examples of useful insights gained from the model thus far with respect to sustainable development of nuclear power.
DEFF Research Database (Denmark)
Hejlesen, Aske K.; Ovesen, Nis
2012-01-01
This paper presents an experimental approach to teaching 3D modelling techniques in an Industrial Design programme. The approach includes the use of tangible free form models as tools for improving the overall learning. The paper is based on lecturer and student experiences obtained through facil...
Energy Technology Data Exchange (ETDEWEB)
NONE
1997-12-31
This report documents a numerical simulation model of the natural gas market in Germany, France, the Netherlands and Belgium. It is a part of a project called ``Internationalization and structural change in the gas market`` aiming to enhance the understanding of the factors behind the current and upcoming changes in the European gas market, especially the downstream part of the gas chain. The model takes European border prices of gas as given, adds transmission and distribution cost and profit margins as well as gas taxes to calculate gas prices. The model includes demand sub-models for households, chemical industry, other industry, the commercial sector and electricity generation. Demand responses to price changes are assumed to take time, and the long run effects are significantly larger than the short run effects. For the household sector and the electricity sector, the dynamics are modeled by distinguishing between energy use in the old and new capital stock. In addition to prices and the activity level (GDP), the model includes the extension of the gas network as a potentially important variable in explaining the development of gas demand. The properties of numerical simulation models are often described by dynamic multipliers, which describe the behaviour of important variables when key explanatory variables are changed. At the end, the report shows the results of a model experiment where the costs in transmission and distribution were reduced. 6 refs., 9 figs., 1 tab.
DEFF Research Database (Denmark)
Yuksel, Ender; Nielson, Hanne Riis; Nielson, Flemming
In this document, we consider a specific Chinese Smart Grid implementation and try to address the verification problem for certain quantitative properties including performance and battery consumption. We employ stochastic model checking approach and present our modelling and analysis study using...
Indian Academy of Sciences (India)
In this talk I review studies of hadron properties in bosonized chiral quark models for the quark ﬂavor dynamics. Mesons are constructed from Bethe–Salpeter equations and baryons emerge as chiral solitons. Such models require regularization and I show that the two-fold Pauli–Villars regularization scheme not only fully ...
Indian Academy of Sciences (India)
ingful. In particular, it is interesting to analyze the hadronic tensor that parametrizes the deep inelastic scattering (DIS) and confront the model predictions with empirical data. This picture has led to interesting studies of hadron structure functions in bosonized chiral quark models. Here I will present the results of refs [5–7].
Building information modelling (BIM)
CSIR Research Space (South Africa)
Conradie, Dirk CU
2009-02-01
Full Text Available The concept of a Building Information Model (BIM) also known as a Building Product Model (BPM) is nothing new. A short article on BIM will never cover the entire filed, because it is a particularly complex filed that is recently beginning to receive...
Haverkort, A.J.; Franke, A.C.; Steyn, J.M.; Pronk, A.A.; Caldiz, D.O.; Kooman, P.L.
2015-01-01
In 1994, LINTUL-POTATO was published, a comprehensive model of potato development and growth. The mechanistic model simulated early crop processes (emergence and leaf expansion) and light interception until extinction, through leaf layers. Photosynthesis and respiration in a previous crop growth
DEFF Research Database (Denmark)
Granados, Alba; Brunskog, Jonas; Misztal, M. K.
2015-01-01
When vocal folds vibrate at normal speaking frequencies, collisions occurs. The numerics and formulations behind a position-based continuum model of contact is an active field of research in the contact mechanics community. In this paper, a frictionless three-dimensional finite element model of t...
Lumped Thermal Household Model
DEFF Research Database (Denmark)
Biegel, Benjamin; Andersen, Palle; Stoustrup, Jakob
2013-01-01
pump portfolio. Following, we illustrate two disadvantages of individual models, namely that it requires much computational effort to optimize over a large portfolio, and second that it is difficult to accurately model the houses in certain time periods due to local disturbances. Finally, we propose...
Jansen, J.D.; Fonseca, R.M.; Kahrobaei, S.; Siraj, M.; Van Essen, G.M.; Van den Hof, P.M.J.
2013-01-01
The "Egg Model" is a synthetic reservoir model consisting of an ensemble of 101 relatively small three-dimensional realizations of a channelized reservoir produced under water flooding conditions with eight water injectors and four producers. It has been used in numerous publications to demonstrate
Dworkin, Nancy; Dworkin, Yehoash
The 1978 Summer Reading Institute, which served 58 Washington, D.C., elementary school children, is described in this paper. Major characteristics of the program model are first identified, along with elements that were added to the model in the preplanning stage. Numerous aspects of the program are then described, including the make-up of the…
Eichinger, John
2005-01-01
Models are crucial to science teaching and learning, yet they can create unforeseen and overlooked challenges for students and teachers. For example, consider the time-tested clay volcano that relies on a vinegar and-baking-soda mixture for its "eruption." Based on a classroom demonstration of that geologic model, elementary students may interpret…
Brozoski, Thomas J; Bauer, Carol A
2016-08-01
Presented is a thematic review of animal tinnitus models from a functional perspective. Chronic tinnitus is a persistent subjective sound sensation, emergent typically after hearing loss. Although the sensation is experientially simple, it appears to have central a nervous system substrate of unexpected complexity that includes areas outside of those classically defined as auditory. Over the past 27 years animal models have significantly contributed to understanding tinnitus' complex neurophysiology. In that time, a diversity of models have been developed, each with its own strengths and limitations. None has clearly become a standard. Animal models trace their origin to the 1988 experiments of Jastreboff and colleagues. All subsequent models derive some of their features from those experiments. Common features include behavior-dependent psychophysical determination, acoustic conditions that contrast objective sound and silence, and inclusion of at least one normal-hearing control group. In the present review, animal models have been categorized as either interrogative or reflexive. Interrogative models use emitted behavior under voluntary control to indicate hearing. An example would be pressing a lever to obtain food in the presence of a particular sound. In this type of model animals are interrogated about their auditory sensations, analogous to asking a patient, "What do you hear?" These models require at least some training and motivation management, and reflect the perception of tinnitus. Reflexive models, in contrast, employ acoustic modulation of an auditory reflex, such as the acoustic startle response. An unexpected loud sound will elicit a reflexive motor response from many species, including humans. Although involuntary, acoustic startle can be modified by a lower-level preceding event, including a silent sound gap. Sound-gap modulation of acoustic startle appears to discriminate tinnitus in animals as well as humans, and requires no training or
Directory of Open Access Journals (Sweden)
Simona Ramanauskaitė
2012-04-01
Full Text Available Preparation for potential threats is one of the most important phases ensuring system security. It allows evaluating possible losses, changes in the attack process, the effectiveness of used countermeasures, optimal system settings, etc. In cyber-attack cases, executing real experiments can be difficult for many reasons. However, mathematical or programming models can be used instead of conducting experiments in a real environment. This work proposes a composite denial of service attack model that combines bandwidth exhaustion, filtering and memory depletion models for a more real representation of similar cyber-attacks. On the basis of the introduced model, different experiments were done. They showed the main dependencies of the influence of attacker and victim’s properties on the success probability of denial of service attack. In the future, this model can be used for the denial of service attack or countermeasure optimization.
Compound semiconductor device modelling
Miles, Robert
1993-01-01
Compound semiconductor devices form the foundation of solid-state microwave and optoelectronic technologies used in many modern communication systems. In common with their low frequency counterparts, these devices are often represented using equivalent circuit models, but it is often necessary to resort to physical models in order to gain insight into the detailed operation of compound semiconductor devices. Many of the earliest physical models were indeed developed to understand the 'unusual' phenomena which occur at high frequencies. Such was the case with the Gunn and IMPATI diodes, which led to an increased interest in using numerical simulation methods. Contemporary devices often have feature sizes so small that they no longer operate within the familiar traditional framework, and hot electron or even quantum mechanical models are required. The need for accurate and efficient models suitable for computer aided design has increased with the demand for a wider range of integrated devices for operation at...
DEFF Research Database (Denmark)
Larsen, Bjarke Alexander; Andkjær, Kasper Ingdahl; Schoenau-Fog, Henrik
2015-01-01
This paper proposes a new relation model, called "The Moody Mask model", for Interactive Digital Storytelling (IDS), based on Franceso Osborne's "Mask Model" from 2011. This, mixed with some elements from Chris Crawford's Personality Models, is a system designed for dynamic interaction between...... characters in an interactive setting. The system was evaluated with a quantitative study investigating the impact of interactivity, with some open-ended questions for qualitative analysis. Furthermore, it was compared with other IDS applications, using the common evaluation method "UxTool". We found...... that the Moody Mask model was not signicantly improved by adding interactivity, except in a few logical areas. It also performed worse than other IDS applications in all areas. The participants reported issues with the lack of feedback from direct actions, repetitive actions, and problems with the story scenario...
Problems in Cybersemiotic Modelling
DEFF Research Database (Denmark)
Brier, Søren
2014-01-01
Uexküll’s cybernetic-behavioral model, which has the problem of being placed in a Platonic, static worldview. The Umwelt of an animal is a construction limited of its functional realism of survival. It is connected to the species. 2. Ture von Uexküll and Søren Brier both realized that Maturana and Varela......’s constructivist biology came closer to a modern version of Jacob von Uexküll’s. Maturana’s model is a relational model. Cognition and communication aims to conserve a viable relation between living system and environment. It is as such not an objective modeling. 3. This model is reinterpreted in biosemiotics...
DEFF Research Database (Denmark)
Benzerga, Ahmed Amine; Leblond, Jean Baptiste; Needleman, Alan
2016-01-01
growth models to account for non-spherical initial void shapes and for shape changes during growth. This includes cases of very low stress triaxiality, where the voids can close up to micro-cracks during the failure process. The void growth models have also been extended to consider the effect of plastic...... anisotropy, or the influence of nonlocal effects that bring a material size scale into the models. Often the voids are not present in the material from the beginning, and realistic nucleation models are important. The final failure process by coalescence of neighboring voids is an issue that has been given...... much attention recently. At ductile fracture, localization of plastic flow is often important, leading to failure by a void-sheet mechanism. Various applications are presented to illustrate the models, including welded specimens, shear tests on butterfly specimens, and analyses of crack growth....
DEFF Research Database (Denmark)
Michea, Adela
This is an ethnographic study of business model innovation in an established manufacturing company. The motivation of the thesis is to propose a sensemaking (Weick, 1995), with focus on enactment (Weick, 1979), analysis of a business model innovation process, stepping outside the usual perspectives...... employed in analysing such a phenomenon, namely activity system, dynamic capability and transaction costs, discovery driven or cognitive perspective. The research question guiding the thesis is: How do established companies enact new business models? The innovation of business models in established...... companies is an intricate process, and a mountain to climb in the eyes of top management. Often, in the choice between innovation and control the latter wins. Studies have shown that technologies and processes, which have the potential to challenge the exiting model, are being filtered out. In here...
Crowdsourcing Business Model Innovation
DEFF Research Database (Denmark)
Waldner, Florian; Poetz, Marion
Successfully adapting existing business models or developing new ones significantly influences a firm?s ability to generate profits and develop competitive advantages. However, business model innovation is perceived as a complex, risky and uncertain process and its success strongly depends...... on whether or not firms are capable of understanding and addressing their customers? needs. This study explores how crowdsourcing-based search approaches can contribute to the process of business model innovation. Drawing on data from a crowdsourcing initiative designed to develop ideas for new business...... models in the podcast industry, we provide first exploratory insights into the value of crowdsourcing for innovating a firm?s business model, and discuss which characteristics of crowd-contributors increase the quantity and quality of the outcome....
Directory of Open Access Journals (Sweden)
Qiong-Tao Xie
2014-06-01
Full Text Available We define the anisotropic Rabi model as the generalization of the spin-boson Rabi model: The Hamiltonian system breaks the parity symmetry; the rotating and counterrotating interactions are governed by two different coupling constants; a further parameter introduces a phase factor in the counterrotating terms. The exact energy spectrum and eigenstates of the generalized model are worked out. The solution is obtained as an elaboration of a recently proposed method for the isotropic limit of the model. In this way, we provide a long-sought solution of a cascade of models with immediate relevance in different physical fields, including (i quantum optics, a two-level atom in single-mode cross-electric and magnetic fields; (ii solid-state physics, electrons in semiconductors with Rashba and Dresselhaus spin-orbit coupling; and (iii mesoscopic physics, Josephson-junction flux-qubit quantum circuits.
Designing Business Model Change
DEFF Research Database (Denmark)
Cavalcante, Sergio Andre
2014-01-01
in a structured and comprehensive way. Such a tool is useful for obtaining an overall view of the working logic of the firm and to facilitate innovation through change. The main contribution of this paper is to transform management theories into an instrument that can be helpful for companies to develop......The aim of this paper is to base organisational change on the firm's business model, an approach that research has only recently start to address. This study adopts a process-based perspective on business models and insights from a variety of theories as the basis for the development of ideas...... on the design of business model change. This paper offers a new, process-based strategic analytical artefact for the design of business model change, consisting of three main phases. Designing business model change as suggested in this paper allows ex ante analysis of alternative scenarios of change...
Directory of Open Access Journals (Sweden)
Mauricio Valenzuela
2017-10-01
Full Text Available We propose a hybrid class of theories for higher spin gravity and matrix models, i.e., which handle simultaneously higher spin gravity fields and matrix models. The construction is similar to Vasiliev’s higher spin gravity, but part of the equations of motion are provided by the action principle of a matrix model. In particular, we construct a higher spin (gravity matrix model related to type IIB matrix models/string theory that have a well defined classical limit, and which is compatible with higher spin gravity in A d S space. As it has been suggested that higher spin gravity should be related to string theory in a high energy (tensionless regime, and, therefore to M-Theory, we expect that our construction will be useful to explore concrete connections.
Integrated Workforce Modeling System
Moynihan, Gary P.
2000-01-01
There are several computer-based systems, currently in various phases of development at KSC, which encompass some component, aspect, or function of workforce modeling. These systems may offer redundant capabilities and/or incompatible interfaces. A systems approach to workforce modeling is necessary in order to identify and better address user requirements. This research has consisted of two primary tasks. Task 1 provided an assessment of existing and proposed KSC workforce modeling systems for their functionality and applicability to the workforce planning function. Task 2 resulted in the development of a proof-of-concept design for a systems approach to workforce modeling. The model incorporates critical aspects of workforce planning, including hires, attrition, and employee development.
Energy Technology Data Exchange (ETDEWEB)
Jones, Katherine A.; Finley, Patrick D.; Moore, Thomas W.; Nozick, Linda Karen; Martin, Nathaniel; Bandlow, Alisa; Detry, Richard Joseph; Evans, Leland B.; Berger, Taylor Eugen
2013-09-01
Infectious diseases can spread rapidly through healthcare facilities, resulting in widespread illness among vulnerable patients. Computational models of disease spread are useful for evaluating mitigation strategies under different scenarios. This report describes two infectious disease models built for the US Department of Veteran Affairs (VA) motivated by a Varicella outbreak in a VA facility. The first model simulates disease spread within a notional contact network representing staff and patients. Several interventions, along with initial infection counts and intervention delay, were evaluated for effectiveness at preventing disease spread. The second model adds staff categories, location, scheduling, and variable contact rates to improve resolution. This model achieved more accurate infection counts and enabled a more rigorous evaluation of comparative effectiveness of interventions.
Cardiovascular modeling and diagnostics
Energy Technology Data Exchange (ETDEWEB)
Kangas, L.J.; Keller, P.E.; Hashem, S.; Kouzes, R.T. [Pacific Northwest Lab., Richland, WA (United States)
1995-12-31
In this paper, a novel approach to modeling and diagnosing the cardiovascular system is introduced. A model exhibits a subset of the dynamics of the cardiovascular behavior of an individual by using a recurrent artificial neural network. Potentially, a model will be incorporated into a cardiovascular diagnostic system. This approach is unique in that each cardiovascular model is developed from physiological measurements of an individual. Any differences between the modeled variables and the variables of an individual at a given time are used for diagnosis. This approach also exploits sensor fusion to optimize the utilization of biomedical sensors. The advantage of sensor fusion has been demonstrated in applications including control and diagnostics of mechanical and chemical processes.
Diffeomorphic Statistical Deformation Models
DEFF Research Database (Denmark)
Hansen, Michael Sass; Hansen, Mads/Fogtman; Larsen, Rasmus
2007-01-01
In this paper we present a new method for constructing diffeomorphic statistical deformation models in arbitrary dimensional images with a nonlinear generative model and a linear parameter space. Our deformation model is a modified version of the diffeomorphic model introduced by Cootes et al....... The modifications ensure that no boundary restriction has to be enforced on the parameter space to prevent folds or tears in the deformation field. For straightforward statistical analysis, principal component analysis and sparse methods, we assume that the parameters for a class of deformations lie on a linear...... manifold and that the distance between two deformations are given by the metric introduced by the L2-norm in the parameter space. The chosen L2-norm is shown to have a clear and intuitive interpretation on the usual nonlinear manifold. Our model is validated on a set of MR images of corpus callosum...
Business Model Process Configurations
DEFF Research Database (Denmark)
Taran, Yariv; Nielsen, Christian; Thomsen, Peter
2015-01-01
Purpose – The paper aims: 1) To develop systematically a structural list of various business model process configuration and to group (deductively) these selected configurations in a structured typological categorization list. 2) To facilitate companies in the process of BM innovation, by develop......Purpose – The paper aims: 1) To develop systematically a structural list of various business model process configuration and to group (deductively) these selected configurations in a structured typological categorization list. 2) To facilitate companies in the process of BM innovation......, by developing (inductively) an ontological classification framework, in view of the BM process configurations typology developed. Design/methodology/approach – Given the inconsistencies found in the business model studies (e.g. definitions, configurations, classifications) we adopted the analytical induction...... method of data analysis. Findings - A comprehensive literature review and analysis resulted in a list of business model process configurations systematically organized under five classification groups, namely, revenue model; value proposition; value configuration; target customers, and strategic...
Hierarchical species distribution models
Hefley, Trevor J.; Hooten, Mevin B.
2016-01-01
Determining the distribution pattern of a species is important to increase scientific knowledge, inform management decisions, and conserve biodiversity. To infer spatial and temporal patterns, species distribution models have been developed for use with many sampling designs and types of data. Recently, it has been shown that count, presence-absence, and presence-only data can be conceptualized as arising from a point process distribution. Therefore, it is important to understand properties of the point process distribution. We examine how the hierarchical species distribution modeling framework has been used to incorporate a wide array of regression and theory-based components while accounting for the data collection process and making use of auxiliary information. The hierarchical modeling framework allows us to demonstrate how several commonly used species distribution models can be derived from the point process distribution, highlight areas of potential overlap between different models, and suggest areas where further research is needed.
Economic communication model set
Zvereva, Olga M.; Berg, Dmitry B.
2017-06-01
This paper details findings from the research work targeted at economic communications investigation with agent-based models usage. The agent-based model set was engineered to simulate economic communications. Money in the form of internal and external currencies was introduced into the models to support exchanges in communications. Every model, being based on the general concept, has its own peculiarities in algorithm and input data set since it was engineered to solve the specific problem. Several and different origin data sets were used in experiments: theoretic sets were estimated on the basis of static Leontief's equilibrium equation and the real set was constructed on the basis of statistical data. While simulation experiments, communication process was observed in dynamics, and system macroparameters were estimated. This research approved that combination of an agent-based and mathematical model can cause a synergetic effect.
Badler, N. I.; Lee, P.; Wong, S.
1985-01-01
Strength modeling is a complex and multi-dimensional issue. There are numerous parameters to the problem of characterizing human strength, most notably: (1) position and orientation of body joints; (2) isometric versus dynamic strength; (3) effector force versus joint torque; (4) instantaneous versus steady force; (5) active force versus reactive force; (6) presence or absence of gravity; (7) body somatotype and composition; (8) body (segment) masses; (9) muscle group envolvement; (10) muscle size; (11) fatigue; and (12) practice (training) or familiarity. In surveying the available literature on strength measurement and modeling an attempt was made to examine as many of these parameters as possible. The conclusions reached at this point toward the feasibility of implementing computationally reasonable human strength models. The assessment of accuracy of any model against a specific individual, however, will probably not be possible on any realistic scale. Taken statistically, strength modeling may be an effective tool for general questions of task feasibility and strength requirements.
Stratiform chromite deposit model
Schulte, Ruth F.; Taylor, Ryan D.; Piatak, Nadine M.; Seal, Robert R.
2010-01-01
Stratiform chromite deposits are of great economic importance, yet their origin and evolution remain highly debated. Layered igneous intrusions such as the Bushveld, Great Dyke, Kemi, and Stillwater Complexes, provide opportunities for studying magmatic differentiation processes and assimilation within the crust, as well as related ore-deposit formation. Chromite-rich seams within layered intrusions host the majority of the world's chromium reserves and may contain significant platinum-group-element (PGE) mineralization. This model of stratiform chromite deposits is part of an effort by the U.S. Geological Survey's Mineral Resources Program to update existing models and develop new descriptive mineral deposit models to supplement previously published models for use in mineral-resource and mineral-environmental assessments. The model focuses on features that may be common to all stratiform chromite deposits as a way to gain insight into the processes that gave rise to their emplacement and to the significant economic resources contained in them.
Auxiliary Deep Generative Models
DEFF Research Database (Denmark)
Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae
2016-01-01
Deep generative models parameterized by neural networks have recently achieved state-of-the-art performance in unsupervised and semi-supervised learning. We extend deep generative models with auxiliary variables which improves the variational approximation. The auxiliary variables leave...... the generative model unchanged but make the variational distribution more expressive. Inspired by the structure of the auxiliary variable we also propose a model with two stochastic layers and skip connections. Our findings suggest that more expressive and properly specified deep generative models converge...... faster with better results. We show state-of-the-art performance within semi-supervised learning on MNIST (0.96%), SVHN (16.61%) and NORB (9.40%) datasets....
Udupa, Jayaram K.; Odhner, Dewey; Falcao, Alexandre X.; Ciesielski, Krzysztof C.; Miranda, Paulo A. V.; Vaideeswaran, Pavithra; Mishra, Shipra; Grevera, George J.; Saboury, Babak; Torigian, Drew A.
2011-03-01
To make Quantitative Radiology (QR) a reality in routine clinical practice, computerized automatic anatomy recognition (AAR) becomes essential. As part of this larger goal, we present in this paper a novel fuzzy strategy for building bodywide group-wise anatomic models. They have the potential to handle uncertainties and variability in anatomy naturally and to be integrated with the fuzzy connectedness framework for image segmentation. Our approach is to build a family of models, called the Virtual Quantitative Human, representing normal adult subjects at a chosen resolution of the population variables (gender, age). Models are represented hierarchically, the descendents representing organs contained in parent organs. Based on an index of fuzziness of the models, 32 thorax data sets, and 10 organs defined in them, we found that the hierarchical approach to modeling can effectively handle the non-linear relationships in position, scale, and orientation that exist among organs in different patients.
Energy Technology Data Exchange (ETDEWEB)
Peskin, M.E.
1997-05-01
These lectures constitute a short course in ``Beyond the Standard Model`` for students of experimental particle physics. The author discusses the general ideas which guide the construction of models of physics beyond the Standard model. The central principle, the one which most directly motivates the search for new physics, is the search for the mechanism of the spontaneous symmetry breaking observed in the theory of weak interactions. To illustrate models of weak-interaction symmetry breaking, the author gives a detailed discussion of the idea of supersymmetry and that of new strong interactions at the TeV energy scale. He discusses experiments that will probe the details of these models at future pp and e{sup +}e{sup {minus}} colliders.
Australia's Next Top Fraction Model
Gould, Peter
2013-01-01
Peter Gould suggests Australia's next top fraction model should be a linear model rather than an area model. He provides a convincing argument and gives examples of ways to introduce a linear model in primary classrooms.
The EMF Model Transformation Framework
E. Biermann; K. Ehrig; C. Ermel; , C. (born Köhler, , C.) Krause (Christian); G. Taentzer; A. Schuerr; M. Nagl; A. Zuendaorf
2008-01-01
htmlabstractWe present the EMF Model Transformation framework (EMT), which supports the rule-based modification of EMF models. Model transformation rules are defined graphically and compiled into Java code to be used in model transformation applications.
Model Reduction in Biomechanics
Feng, Yan
The mechanical characteristic of the cell is primarily performed by the cytoskeleton. Microtubules, actin, and intermediate filaments are the three main cytoskeletal polymers. Of these, microtubules are the stiffest and have multiple functions within a cell that include: providing tracks for intracellular transport, transmitting the mechanical force necessary for cell division during mitosis, and providing sufficient stiffness for propulsion in flagella and cilia. Microtubule mechanics has been studied by a variety of methods: detailed molecular dynamics (MD), coarse-grained models, engineering type models, and elastic continuum models. In principle, atomistic MD simulations should be able to predict all desired mechanical properties of a single molecule, however, in practice the large computational resources are required to carry out a simulation of larger biomolecular system. Due to the limited accessibility using even the most ambitious all-atom models and the demand for the multiscale molecular modeling and simulation, the emergence of the reduced models is critically important to provide the capability for investigating the biomolecular dynamics that are critical to many biological processes. Then the coarse-grained models, such as elastic network models and anisotropic network models, have been shown to bequite accurate in predicting microtubule mechanical response, but still requires significant computational resources. On the other hand, the microtubule is treated as comprising materials with certain continuum material properties. Such continuum models, especially Euler-Bernoulli beam models, are often used to extract mechanical parameters from experimental results. The microtubule is treated as comprising materials with certain continuum material properties. Such continuum models, especially Euler-Bernoulli beam models in which the biomolecular system is assumed as homogeneous isotropic materials with solid cross-sections, are often used to extract
Antedependence models for longitudinal data
Zimmerman, Dale L
2009-01-01
The First Book Dedicated to This Class of Longitudinal ModelsAlthough antedependence models are particularly useful for modeling longitudinal data that exhibit serial correlation, few books adequately cover these models. By gathering results scattered throughout the literature, Antedependence Models for Longitudinal Data offers a convenient, systematic way to learn about antedependence models. Illustrated with numerous examples, the book also covers some important statistical inference procedures associated with these models.After describing unstructured and structured antedependence models an
Shaham, Jacob
1987-01-01
Models for explaining the phenomenon of quasi-periodic oscillations (QPOs) are reviewed, concentrating on the beat frequency model. It is suggested that the beat frequency model, which was developed to describe GX 5-1, is the best available model. The equations which this model uses to describe the QPO modulation are presented and problems of the beat frequency model are considered.
SPAR Model Structural Efficiencies
Energy Technology Data Exchange (ETDEWEB)
John Schroeder; Dan Henry
2013-04-01
The Nuclear Regulatory Commission (NRC) and the Electric Power Research Institute (EPRI) are supporting initiatives aimed at improving the quality of probabilistic risk assessments (PRAs). Included in these initiatives are the resolution of key technical issues that are have been judged to have the most significant influence on the baseline core damage frequency of the NRC’s Standardized Plant Analysis Risk (SPAR) models and licensee PRA models. Previous work addressed issues associated with support system initiating event analysis and loss of off-site power/station blackout analysis. The key technical issues were: • Development of a standard methodology and implementation of support system initiating events • Treatment of loss of offsite power • Development of standard approach for emergency core cooling following containment failure Some of the related issues were not fully resolved. This project continues the effort to resolve outstanding issues. The work scope was intended to include substantial collaboration with EPRI; however, EPRI has had other higher priority initiatives to support. Therefore this project has addressed SPAR modeling issues. The issues addressed are • SPAR model transparency • Common cause failure modeling deficiencies and approaches • Ac and dc modeling deficiencies and approaches • Instrumentation and control system modeling deficiencies and approaches
Stochasticity Modeling in Memristors
Naous, Rawan
2015-10-26
Diverse models have been proposed over the past years to explain the exhibiting behavior of memristors, the fourth fundamental circuit element. The models varied in complexity ranging from a description of physical mechanisms to a more generalized mathematical modeling. Nonetheless, stochasticity, a widespread observed phenomenon, has been immensely overlooked from the modeling perspective. This inherent variability within the operation of the memristor is a vital feature for the integration of this nonlinear device into the stochastic electronics realm of study. In this paper, experimentally observed innate stochasticity is modeled in a circuit compatible format. The model proposed is generic and could be incorporated into variants of threshold-based memristor models in which apparent variations in the output hysteresis convey the switching threshold shift. Further application as a noise injection alternative paves the way for novel approaches in the fields of neuromorphic engineering circuits design. On the other hand, extra caution needs to be paid to variability intolerant digital designs based on non-deterministic memristor logic.
Aydoğdu, A; Frasca, P; D'Apice, C; Manzo, R; Thornton, J M; Gachomo, B; Wilson, T; Cheung, B; Tariq, U; Saidel, W; Piccoli, B
2017-02-21
In this paper we introduce a mathematical model to study the group dynamics of birds resting on wires. The model is agent-based and postulates attraction-repulsion forces between the interacting birds: the interactions are "topological", in the sense that they involve a given number of neighbors irrespective of their distance. The model is first mathematically analyzed and then simulated to study its main properties: we observe that the model predicts birds to be more widely spaced near the borders of each group. We compare the results from the model with experimental data, derived from the analysis of pictures of pigeons and starlings taken in New Jersey: two different image elaboration protocols allow us to establish a good agreement with the model and to quantify its main parameters. We also discuss the potential handedness of the birds, by analyzing the group organization features and the group dynamics at the arrival of new birds. Finally, we propose a more refined mathematical model that describes landing and departing birds by suitable stochastic processes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Chan, Philemon; Ho, Kevin; Ryan, Allen F
2016-05-01
The new Auditory 4.0 model has been developed for the assessment of auditory outcomes, expressed as temporary threshold shift (TTS) and permanent threshold shift (PTS), from exposures to impulse noise for unprotected ears, including the prediction of TTS recovery. Auditory 4.0 is an empirical model, constructed from test data collected from chinchillas exposed to impulse noise in the laboratory. Injury outcomes are defined as TTS and PTS, and Auditory 4.0 provides the full range of TTS and PTS dose-response curves with the risk factor constructed from A-weighted sound exposure level. Human data from large weapons noise exposure was also used to guide the development of the recovery model. Guided by data, a 28-dBA shift was applied to the dose-response curves to account for the scaling from chinchillas to humans. Historical data from rifle noise tests were used to validate the dose-response curves. New chinchilla tests were performed to collect recovery data to construct the TTS recovery model. Auditory 4.0 is the only model known to date that provides the full TTS and PTS dose-response curves, including a TTS recovery model. The model shows good agreement with historical data. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.
Invertebrate models of alcoholism.
Scholz, Henrike; Mustard, Julie A
2013-01-01
For invertebrates to become useful models for understanding the genetic and physiological mechanisms of alcoholism related behaviors and the predisposition towards alcoholism, several general requirements must be fulfilled. The animal should encounter ethanol in its natural habitat, so that the central nervous system of the organism will have evolved mechanisms for responding to ethanol exposure. How the brain adapts to ethanol exposure depends on its access to ethanol, which can be regulated metabolically and/or by physical barriers. Therefore, a model organism should have metabolic enzymes for ethanol degradation similar to those found in humans. The neurons and supporting glial cells of the model organism that regulate behaviors affected by ethanol should share the molecular and physiological pathways found in humans, so that results can be compared. Finally, the use of invertebrate models should offer advantages over traditional model systems and should offer new insights into alcoholism-related behaviors. In this review we will summarize behavioral similarities and identified genes and mechanisms underlying ethanol-induced behaviors in invertebrates. This review mainly focuses on the use of the nematode Caenorhabditis elegans, the honey bee Apis mellifera and the fruit fly Drosophila melanogaster as model systems. We will discuss insights gained from those studies in conjunction with their vertebrate model counterparts and the implications for future research into alcoholism and alcohol-induced behaviors.
Computationally modeling interpersonal trust
Lee, Jin Joo; Knox, W. Bradley; Wormwood, Jolie B.; Breazeal, Cynthia; DeSteno, David
2013-01-01
We present a computational model capable of predicting—above human accuracy—the degree of trust a person has toward their novel partner by observing the trust-related nonverbal cues expressed in their social interaction. We summarize our prior work, in which we identify nonverbal cues that signal untrustworthy behavior and also demonstrate the human mind's readiness to interpret those cues to assess the trustworthiness of a social robot. We demonstrate that domain knowledge gained from our prior work using human-subjects experiments, when incorporated into the feature engineering process, permits a computational model to outperform both human predictions and a baseline model built in naiveté of this domain knowledge. We then present the construction of hidden Markov models to investigate temporal relationships among the trust-related nonverbal cues. By interpreting the resulting learned structure, we observe that models built to emulate different levels of trust exhibit different sequences of nonverbal cues. From this observation, we derived sequence-based temporal features that further improve the accuracy of our computational model. Our multi-step research process presented in this paper combines the strength of experimental manipulation and machine learning to not only design a computational trust model but also to further our understanding of the dynamics of interpersonal trust. PMID:24363649
Combining thermal comfort models
Energy Technology Data Exchange (ETDEWEB)
Yigit, A.
1999-07-01
Two models commonly used in thermal comfort studies were combined to develop a two-dimensional computer model that estimates the resistance to dry and evaporative heat transfer for a clothing system from fabric resistance data, fabric thickness data, and information concerning the amount of body surface area covered by different fabric layers and the amount of air trapped between fabric layers. Five different clothing ensembles with different total thermal insulation and very different distributions of the insulation on the body were simulated with 16 sedentary subjects. This paper first evaluates total thermal insulation predictions from the Fanger steady-state model and then uses these data in the Gagge two-compartment (or two-node) model. The combined model uses the transient heat balance of each segment and the whole body. It estimates total insulation value and then uses this value to calculate transient temperature and wettedness. By application of the combined model, predictions of human responses to a wide range of thermal conditions are compared with the responses of human subjects as described in reports of laboratory experiments. Possible reasons for discrepancies between the observed data and predictions of the model are briefly discussed.
Mouse Models of Arteriosclerosis
Xu, Qingbo
2004-01-01
Animal models are designed to be preliminary tools for better understanding of the pathogenesis, improvement in diagnosis, prevention, and therapy of arteriosclerosis in humans. Attracted by the well-defined genetic systems, a number of investigators have begun to use the mouse as an experimental system for arteriosclerosis research. Hundreds of inbred lines have been established, and the genetic map is relatively well defined, and both congenic strains and recombinant strains are available to facilitate genetic experimentation. Because arteriosclerosis is a complicated disease, which includes spontaneous (native) atherosclerosis, transplant arteriosclerosis, vein graft atherosclerosis, and angioplasty-induced restenosis, several mouse models for studying all types of arteriosclerosis have recently been established. Using these mouse models, much knowledge concerning the pathogenesis of the disease and therapeutic intervention has been gained, eg, origins of endothelial and smooth muscle cells in lesions of transplant and vein graft atherosclerosis. This review will not attempt to cover all aspects of mouse models, rather focus on models of arterial injuries, vein grafts, and transplant arteriosclerosis, by which the major progress in understanding the mechanisms of the disease has been made. This article will also point out (dis)advantages of a variety of models, and how the models can be appropriately chosen for different purposes of study. PMID:15215157
Computationally Modeling Interpersonal Trust
Directory of Open Access Journals (Sweden)
Jin Joo eLee
2013-12-01
Full Text Available We present a computational model capable of predicting—above human accuracy—the degree of trust a person has toward their novel partner by observing the trust-related nonverbal cues expressed in their social interaction. We summarize our prior work, in which we identify nonverbal cues that signal untrustworthy behavior and also demonstrate the human mind’s readiness to interpret those cues to assess the trustworthiness of a social robot. We demonstrate that domain knowledge gained from our prior work using human-subjects experiments, when incorporated into the feature engineering process, permits a computational model to outperform both human predictions and a baseline model built in naivete' of this domain knowledge. We then present the construction of hidden Markov models to incorporate temporal relationships among the trust-related nonverbal cues. By interpreting the resulting learned structure, we observe that models built to emulate different levels of trust exhibit different sequences of nonverbal cues. From this observation, we derived sequence-based temporal features that further improve the accuracy of our computational model. Our multi-step research process presented in this paper combines the strength of experimental manipulation and machine learning to not only design a computational trust model but also to further our understanding of the dynamics of interpersonal trust.
Animal Models of Atherosclerosis
Getz, Godfrey S.; Reardon, Catherine A.
2012-01-01
Atherosclerosis is a chronic inflammatory disorder that is the underlying cause of most cardiovascular disease. Both cells of the vessel wall and cells of the immune system participate in atherogenesis. This process is heavily influenced by plasma lipoproteins, genetics and the hemodynamics of the blood flow in the artery. A variety of small and large animal models have been used to study the atherogenic process. No model is ideal as each has its own advantages and limitations with respect to manipulation of the atherogenic process and modeling human atherosclerosis or lipoprotein profile. Useful large animal models include pigs, rabbits and non-human primates. Due in large part to the relative ease of genetic manipulation and the relatively short time frame for the development of atherosclerosis, murine models are currently the most extensively used. While not all aspects of murine atherosclerosis are identical to humans, studies using murine models have suggested potential biological processes and interactions that underlie this process. As it becomes clear that different factors may influence different stages of lesion development, the use of mouse models with the ability to turn on or delete proteins or cells in tissue specific and temporal manner will be very valuable. PMID:22383700
Energy Technology Data Exchange (ETDEWEB)
Mitev, Vladimir
2010-08-15
The purpose of this thesis is to deepen our understanding of the fundamental properties and defining features of non-linear sigma models on superspaces. We begin by presenting the major concepts that we have used in our investigation, namely Lie superalgebras and supergroups, non-linear sigma models and two dimensional conformal field theory. We then exhibit a method, called cohomological reduction, that makes use of the target space supersymmetry of non-linear sigma models to compute certain correlation functions. We then show how the target space supersymmetry of Ricci flat Lie supergroups simplifies the perturbation theory of suitable deformed Wess-Zumino-Witten models, making it possible to compute boundary conformal weights to all orders. This is then applied to the OSP (2S+2 vertical stroke 2S) Gross-Neveu Model, leading to a dual description in terms of the sigma model on the supersphere S{sup 2S+1} {sup vertical} {sup stroke} {sup 2S}. With this results in mind, we then turn to the similar, yet more intricate, theory of the non-linear sigma model on the complex projective superspaces CP{sup N-1} {sup vertical} {sup stroke} {sup N}. The cohomological reduction allows us to compute several important quantities non-perturbatively with the help of the system of symplectic fermions. Combining this with partial perturbative results for the whole theory, together with numerical computations, we propose a conjecture for the exact evolution of boundary conformal weights for symmetry preserving boundary conditions. (orig.)
Staged Models for Interdisciplinary Research
Lafuerza, Luis F; Edmonds, Bruce; McKane, Alan J
2016-01-01
Modellers of complex biological or social systems are often faced with an invidious choice: to use simple models with few mechanisms that can be fully analysed, or to construct complicated models that include all the features which are thought relevant. The former ensures rigour, the latter relevance. We discuss a method that combines these two approaches, beginning with a complex model and then modelling the complicated model with simpler models. The resulting "chain" of models ensures some rigour and relevance. We illustrate this process on a complex model of voting intentions, constructing a reduced model which agrees well with the predictions of the full model. Experiments with variations of the simpler model yield additional insights which are hidden by the complexity of the full model. This approach facilitated collaboration between social scientists and physicists -- the complex model was specified based on the social science literature, and the simpler model constrained to agree (in core aspects) with...
Ramasubramanian, S
2009-01-01
Insurance has become a necessary aspect of modern society. The mathematical basis of insurance modeling is best expressed in terms of continuous time stochastic processes. This introductory text on actuarial risk theory deals with the Cramer-Lundberg model and the renewal risk model. Their basic structure and properties, including the renewal theorems as well as the corresponding ruin problems, are studied. There is a detailed discussion of heavy tailed distributions, which have become increasingly relevant. The Lundberg risk process with investment in risky asset is also considered. This book will be useful to practitioners in the field and to graduate students interested in this important branch of applied probability.
Animal Model of Dermatophytosis
Directory of Open Access Journals (Sweden)
Tsuyoshi Shimamura
2012-01-01
Full Text Available Dermatophytosis is superficial fungal infection caused by dermatophytes that invade the keratinized tissue of humans and animals. Lesions from dermatophytosis exhibit an inflammatory reaction induced to eliminate the invading fungi by using the host’s normal immune function. Many scientists have attempted to establish an experimental animal model to elucidate the pathogenesis of human dermatophytosis and evaluate drug efficacy. However, current animal models have several issues. In the present paper, we surveyed reports about the methodology of the dermatophytosis animal model for tinea corporis, tinea pedis, and tinea unguium and discussed future prospects.
Acoustic Model Testing Chronology
Nesman, Tom
2017-01-01
Scale models have been used for decades to replicate liftoff environments and in particular acoustics for launch vehicles. It is assumed, and analyses supports, that the key characteristics of noise generation, propagation, and measurement can be scaled. Over time significant insight was gained not just towards understanding the effects of thruster details, pad geometry, and sound mitigation but also to the physical processes involved. An overview of a selected set of scale model tests are compiled here to illustrate the variety of configurations that have been tested and the fundamental knowledge gained. The selected scale model tests are presented chronologically.
DEFF Research Database (Denmark)
Benzerga, Ahmed Amine; Leblond, Jean Baptiste; Needleman, Alan
2016-01-01
much attention recently. At ductile fracture, localization of plastic flow is often important, leading to failure by a void-sheet mechanism. Various applications are presented to illustrate the models, including welded specimens, shear tests on butterfly specimens, and analyses of crack growth....... growth models to account for non-spherical initial void shapes and for shape changes during growth. This includes cases of very low stress triaxiality, where the voids can close up to micro-cracks during the failure process. The void growth models have also been extended to consider the effect of plastic...
Kavka, P.; Jeřábek, J.; Strouhal, L.
2016-12-01
The contribution presents a numerical model SMODERP that is used for calculation and prediction of surface runoff and soil erosion from agricultural land. The physically based model includes the processes of infiltration (Phillips equation), surface runoff routing (kinematic wave based equation), surface retention, surface roughness and vegetation impact on runoff. The model is being developed at the Department of Irrigation, Drainage and Landscape Engineering, Civil Engineering Faculty, CTU in Prague. 2D version of the model was introduced in last years. The script uses ArcGIS system tools for data preparation. The physical relations are implemented through Python scripts. The main computing part is stand alone in numpy arrays. Flow direction is calculated by Steepest Descent algorithm and in multiple flow algorithm. Sheet flow is described by modified kinematic wave equation. Parameters for five different soil textures were calibrated on the set of hundred measurements performed on the laboratory and filed rainfall simulators. Spatially distributed models enable to estimate not only surface runoff but also flow in the rills. Development of the rills is based on critical shear stress and critical velocity. For modelling of the rills a specific sub model was created. This sub model uses Manning formula for flow estimation. Flow in the ditches and streams are also computed. Numerical stability of the model is controled by Courant criterion. Spatial scale is fixed. Time step is dynamic and depends on the actual discharge. The model is used in the framework of the project "Variability of Short-term Precipitation and Runoff in Small Czech Drainage Basins and its Influence on Water Resources Management". Main goal of the project is to elaborate a methodology and online utility for deriving short-term design precipitation series, which could be utilized by a broad community of scientists, state administration as well as design planners. The methodology will account for
The Finslerian wormhole models
Energy Technology Data Exchange (ETDEWEB)
Rahaman, Farook; Paul, Nupur; Banerjee, Ayan [Jadavpur University, Department of Mathematics, Kolkata, West Bengal (India); De, S.S. [University of Calcutta, Department of Applied Mathematics, Kolkata, West Bengal (India); Ray, Saibal [Government College of Engineering and Ceramic Technology, Department of Physics, Kolkata, West Bengal (India); Usmani, A.A. [Aligarh Muslim University, Department of Physics, Aligarh, Uttar Pradesh (India)
2016-05-15
We present models of wormhole under the Finslerian structure of spacetime. This is a sequel of our previous work (Eur Phys J 75:564, 2015) where we constructed a toy model for compact stars based on the Finslerian spacetime geometry. In the present investigation, a wide variety of solutions are obtained, which explore the wormhole geometry by considering different choices for the form function and energy density. The solutions, like in the previous work, are revealed to be physically interesting and viable models for the explanation of wormholes as far as the background theory and literature are concerned. (orig.)
Nonparametric Transfer Function Models
Liu, Jun M.; Chen, Rong; Yao, Qiwei
2009-01-01
In this paper a class of nonparametric transfer function models is proposed to model nonlinear relationships between ‘input’ and ‘output’ time series. The transfer function is smooth with unknown functional forms, and the noise is assumed to be a stationary autoregressive-moving average (ARMA) process. The nonparametric transfer function is estimated jointly with the ARMA parameters. By modeling the correlation in the noise, the transfer function can be estimated more efficiently. The parsimonious ARMA structure improves the estimation efficiency in finite samples. The asymptotic properties of the estimators are investigated. The finite-sample properties are illustrated through simulations and one empirical example. PMID:20628584
Modelling Hyperboloid Sound Scattering
DEFF Research Database (Denmark)
Burry, Jane; Davis, Daniel; Peters, Brady
2011-01-01
The Responsive Acoustic Surfaces workshop project described here sought new understandings about the interaction between geometry and sound in the arena of sound scattering. This paper reports on the challenges associated with modelling, simulating, fabricating and measuring this phenomenon using...... both physical and digital models at three distinct scales. The results suggest hyperboloid geometry, while difficult to fabricate, facilitates sound scattering.......The Responsive Acoustic Surfaces workshop project described here sought new understandings about the interaction between geometry and sound in the arena of sound scattering. This paper reports on the challenges associated with modelling, simulating, fabricating and measuring this phenomenon using...
Energy Technology Data Exchange (ETDEWEB)
Smith, P.A. [SAM Switzerland GmbH (Switzerland); Brommundt, J.; Mayer, G. [AF-Consult Switzerland Ltd, Baden (Switzerland)] [and others
2012-01-15
This report presents a preliminary plan for the development and application of models for the probabilistic sensitivity analyses and the deterministic calculation cases that will be used to analyse scenarios in the 2012 safety case. The plan addresses both groundwater flow modelling and radionuclide transport modelling, primarily of the repository near field and of the geosphere. It also addresses the measures that will be applied during the implementation and documentation of the calculations that will contribute to the quality assurance of the safety case. It is expected that this plan will be refined and amended as experience is gained during the carrying out of the work. (orig.)
Prest, M
1988-01-01
In recent years the interplay between model theory and other branches of mathematics has led to many deep and intriguing results. In this, the first book on the topic, the theme is the interplay between model theory and the theory of modules. The book is intended to be a self-contained introduction to the subject and introduces the requisite model theory and module theory as it is needed. Dr Prest develops the basic ideas concerning what can be said about modules using the information which may be expressed in a first-order language. Later chapters discuss stability-theoretic aspects of module
DEFF Research Database (Denmark)
Olsson, I. Anna S.; Sandøe, Peter
2011-01-01
This chapter aims to encourage scientists and others interested in the use of animal models of disease – specifically, in the study of dementia – to engage in ethical reflection. It opens with a general discussion of the moral acceptability of animal use in research. Three ethical approaches...... are here distinguished. These serve as points of orientation in the following discussion of four more specific ethical questions: Does animal species matter? How effective is disease modelling in delivering the benefits claimed for it? What can be done to minimize potential harm to animals in research? Who...... bears responsibility for the use of animals in disease models?...
Modeling EERE Deployment Programs
Energy Technology Data Exchange (ETDEWEB)
Cort, Katherine A.; Hostick, Donna J.; Belzer, David B.; Livingston, Olga V.
2007-11-08
The purpose of this report is to compile information and conclusions gathered as part of three separate tasks undertaken as part of the overall project, “Modeling EERE Deployment Programs,” sponsored by the Planning, Analysis, and Evaluation office within the Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE). The purpose of the project was to identify and characterize the modeling of deployment programs within the EERE Technology Development (TD) programs, address improvements to modeling in the near term, and note gaps in knowledge where future research is needed.
Introducing Program Evaluation Models
Directory of Open Access Journals (Sweden)
Raluca GÂRBOAN
2008-02-01
Full Text Available Programs and project evaluation models can be extremely useful in project planning and management. The aim is to set the right questions as soon as possible in order to see in time and deal with the unwanted program effects, as well as to encourage the positive elements of the project impact. In short, different evaluation models are used in order to minimize losses and maximize the benefits of the interventions upon small or large social groups. This article introduces some of the most recently used evaluation models.
Rossetti, Manuel D
2015-01-01
Emphasizes a hands-on approach to learning statistical analysis and model building through the use of comprehensive examples, problems sets, and software applications With a unique blend of theory and applications, Simulation Modeling and Arena®, Second Edition integrates coverage of statistical analysis and model building to emphasize the importance of both topics in simulation. Featuring introductory coverage on how simulation works and why it matters, the Second Edition expands coverage on static simulation and the applications of spreadsheets to perform simulation. The new edition als
Open source molecular modeling.
Pirhadi, Somayeh; Sunseri, Jocelyn; Koes, David Ryan
2016-09-01
The success of molecular modeling and computational chemistry efforts are, by definition, dependent on quality software applications. Open source software development provides many advantages to users of modeling applications, not the least of which is that the software is free and completely extendable. In this review we categorize, enumerate, and describe available open source software packages for molecular modeling and computational chemistry. An updated online version of this catalog can be found at https://opensourcemolecularmodeling.github.io. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.
Costa Junior, Celso Jose
2016-01-01
While the theoretical development of DSGE models is not overly difficult to understand, practical application remains somewhat complex. The literature on this subject has some significant obscure points. This book can be thought of, firstly, as a tool to overcome initial hurdles with this type of modeling. Secondly, by showcasing concrete applications, it aims to persuade incipient researchers to work with this methodology. In principle, this is not a book on macroeconomics in itself, but on tools used in the construction of this sort of models. It strives to present this technique in a detail
DEFF Research Database (Denmark)
Bec, Frederique; Rahbek, Anders Christian; Shephard, Neil
2008-01-01
This paper proposes and analyses the autoregressive conditional root (ACR) time-series model. This multivariate dynamic mixture autoregression allows for non-stationary epochs. It proves to be an appealing alternative to existing nonlinear models, e.g. the threshold autoregressive or Markov...... switching class of models, which are commonly used to describe nonlinear dynamics as implied by arbitrage in presence of transaction costs. Simple conditions on the parameters of the ACR process and its innovations are shown to imply geometric ergodicity, stationarity and existence of moments. Furthermore...
Dynamical holographic QCD model
Directory of Open Access Journals (Sweden)
Li Danning
2014-01-01
Full Text Available We develop a dynamical holographic QCD model, which resembles the renormalization group from ultraviolet (UV to infrared (IR. The dynamical holographic model is constructed in the graviton-dilaton-scalar framework with the dilaton background field Φ and scalar field X responsible for the gluodynamics and chiral dynamics, respectively. We summarize the results on hadron spectra, QCD phase transition and transport properties including the jet quenching parameter and the shear/bulk viscosity in the framework of the dynamical holographic QCD model.
Demand Modelling in Telecommunications
Directory of Open Access Journals (Sweden)
M. Chvalina
2009-01-01
Full Text Available This article analyses the existing possibilities for using Standard Statistical Methods and Artificial Intelligence Methods for a short-term forecast and simulation of demand in the field of telecommunications. The most widespread methods are based on Time Series Analysis. Nowadays, approaches based on Artificial Intelligence Methods, including Neural Networks, are booming. Separate approaches will be used in the study of Demand Modelling in Telecommunications, and the results of these models will be compared with actual guaranteed values. Then we will examine the quality of Neural Network models.
Modeling microtubule oscillations
DEFF Research Database (Denmark)
Jobs, E.; Wolf, D.E.; Flyvbjerg, H.
1997-01-01
Synchronization of molecular reactions in a macroscopic volume may cause the volume's physical properties to change dynamically and thus reveal much about the reactions. As an example, experimental time series for so-called microtubule oscillations are analyzed in terms of a minimal model...... for this complex polymerization-depolymerization cycle. The model reproduces well the qualitatively different time series that result from different experimental conditions, and illuminates the role and importance of individual processes in the cycle. Simple experiments are suggested that can further test...... and define the model and the polymer's reaction cycle....
Energy Technology Data Exchange (ETDEWEB)
Longas, Robinson; Portillo, Dilia; Restrepo, Diego; Zapata, Oscar [Instituto de Física, Universidad de Antioquia,Calle 70 No. 52-21, Medellín (Colombia)
2016-03-23
We study a realization of the topology of the Zee model for the generation of neutrino masses at one-loop with a minimal set of vector-like fermions. After imposing an exact Z{sub 2} symmetry to avoid tree-level Higgs-mediated flavor changing neutral currents, one dark matter candidate is obtained from the subjacent inert doublet model, but with the presence of new co-annihilating particles. We show that the model is consistent with the constraints coming from lepton flavor violation processes, oblique parameters, dark matter and neutrino oscillation data.
Magnetospheric models for QPOs
Shaham, Jacob
1988-01-01
Models of quasi-periodic oscillation (QPOs) based on the assumption that QPOs have magnetospheres are discussed. Evidence supporting the use of magnetospheric models is presented. The study of low frequency noise in the blob model is examined, stressing the question of the how much the blob-to-blob correlation is needed to suppress the low frequency noise to the levels observed in QPO sources. It is suggested that in low mass X-ray binaries, larger amounts of energy should be expected to be released at the magnetospheric boundary rather than on the neutron stellar surface. Also, examples of reproducing hardness ratio curves and QPO frequencies are given.
Applied impulsive mathematical models
Stamova, Ivanka
2016-01-01
Using the theory of impulsive differential equations, this book focuses on mathematical models which reflect current research in biology, population dynamics, neural networks and economics. The authors provide the basic background from the fundamental theory and give a systematic exposition of recent results related to the qualitative analysis of impulsive mathematical models. Consisting of six chapters, the book presents many applicable techniques, making them available in a single source easily accessible to researchers interested in mathematical models and their applications. Serving as a valuable reference, this text is addressed to a wide audience of professionals, including mathematicians, applied researchers and practitioners.
Energy Technology Data Exchange (ETDEWEB)
Shumway, R.W.
1987-10-01
The ATHENA computer program has many features that make it desirable to use as a space reactor evaluation tool. One of the missing features was a surface-to-surface thermal radiation model. A model was developed that allows any of the regular ATHENA heat slabs to radiate to any other heat slab. The view factors and surface emissivities must be specified by the user. To verify that the model was properly accounting for radiant energy transfer, two different types of test calculations were performed. Both calculations have excellent results. The updates have been used on both the INEL CDC-176 and the Livermore Cray. 7 refs., 2 figs., 6 tabs.
Identification of physical models
DEFF Research Database (Denmark)
Melgaard, Henrik
1994-01-01
of the model with the available prior knowledge. The methods for identification of physical models have been applied in two different case studies. One case is the identification of thermal dynamics of building components. The work is related to a CEC research project called PASSYS (Passive Solar Components...... and Systems Testing), on testing of building components related to passive solar energy conservation, tested under outdoor climate conditions. The second case study is related to the performance of a spark ignition car engine. A phenomenological model of the fuel flow is identified under various operating...
Absorption in dielectric models
Churchill, R J
2015-01-01
We develop a classical microscopic model of a dielectric. The model features nonlinear interaction terms between polarizable dipoles and lattice vibrations. The lattice vibrations are found to act as a pseudo-reservoir, giving broadband absorption of electromagnetic radiation without the addition of damping terms in the dynamics. The effective permittivity is calculated using a perturbative iteration method and is found to have the form associated with real dielectrics. Spatial dispersion is naturally included in the model and we also calculate the wavevector dependence of the permittivity.
Perspectives on multifield models
Energy Technology Data Exchange (ETDEWEB)
Banerjee, S. [Univ. of California, Santa Barbara, CA (United States)
1997-07-01
Multifield models for prediction of nuclear reactor thermalhydraulics are reviewed from the viewpoint of their structure and requirements for closure relationships. Their strengths and weaknesses are illustrated with examples, indicating that they are effective in predicting separated and distributed flow regimes, but have problems for flows with large oscillations. Needs for multifield models are also discussed in the context of reactor operations and accident simulations. The highest priorities for future developments appear to relate to closure relationships for three-dimensional multifield models with emphasis on those needed for calculations of phase separation and entrainment/de-entrainment in complex geometries.
Mathematical modelling of metabolism
DEFF Research Database (Denmark)
Gombert, Andreas Karoly; Nielsen, Jens
2000-01-01
Mathematical models of the cellular metabolism have a special interest within biotechnology. Many different kinds of commercially important products are derived from the cell factory, and metabolic engineering can be applied to improve existing production processes, as well as to make new processes...... availability of genomic information and powerful analytical techniques, mathematical models also serve as a tool for understanding the cellular metabolism and physiology....... available. Both stoichiometric and kinetic models have been used to investigate the metabolism, which has resulted in defining the optimal fermentation conditions, as well as in directing the genetic changes to be introduced in order to obtain a good producer strain or cell line. With the increasing...
Morrow, C. T. (Principal Investigator)
1981-01-01
Measurements of wind speed, net irradiation, and of air, soil, and dew point temperatures in an orchard at the Rock Springs Agricultural Research Center, as well as topographical and climatological data and a description of the major apple growing regions of Pennsylvania were supplied to the University of Florida for use in running the P-model, freeze prediction program. Results show that the P-model appears to have considerable applicability to conditions in Pennsylvania. Even though modifications may have to be made for use in the fruit growing regions, there are advantages for fruit growers with the model in its present form.
Competitive facility location models
Kononov, A. V.; Kochetov, Yu. A.; Plyasunov, A. V.
2009-06-01
Two classes of competitive facility location models are considered, in which several persons (players) sequentially or simultaneously open facilities for serving clients. The first class consists of discrete two-level programming models. The second class consists of game models with several independent players pursuing selfish goals. For the first class, its relationship with pseudo-Boolean functions is established and a novel method for constructing a family of upper and lower bounds on the optimum is proposed. For the second class, the tight PLS-completeness of the problem of finding Nash equilibriums is proved.
CERN. Geneva HR-RFA
2006-01-01
Suggested Readings: Aspects of Quantum Chromodynamics/A Pich, arXiv:hep-ph/0001118. - The Standard Model of Electroweak Interactions/A Pich, arXiv:hep-ph/0502010. - The Standard Model of Particle Physics/A Pich The Standard Model of Elementary Particle Physics will be described. A detailed discussion of the particle content, structure and symmetries of the theory will be given, together with an overview of the most important experimental facts which have established this theoretical framework as the Standard Theory of particle interactions.
Energy Technology Data Exchange (ETDEWEB)
Kimpland, Robert Herbert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Goettee, Jeffrey D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-03-10
A dynamic system simulation model of the WSMR Fast Burst Reactor (FBR) has been developed to simulate the time-dependent behavior of prompt burst excursions. The model combines neutron kinetics with fuel material hydrodynamics to track both fission power and the thermo-physical response of the fuel. This model is used to characterize prompt burst behavior, such as spike yield and pulse FWHM, and to serve as a time-dependent source for predicting associated FBR phenomena, such as electric field generation and atmospheric fluorescence.
The Hydra model - a model for what?
Gierer, Alfred
2012-01-01
The introductory personal remarks refer to my motivations for choosing research projects, and for moving from physics to molecular biology and then to development, with Hydra as a model system. Historically, Trembley's discovery of Hydra regeneration in 1744 was the beginning of developmental biology as we understand it, with passionate debates about preformation versus de novo generation, mechanisms versus organisms. In fact, seemingly conflicting bottom-up and top-down concepts are both required in combination to understand development. In modern terms, this means analysing the molecules involved, as well as searching for physical principles underlying development within systems of molecules, cells and tissues. During the last decade, molecular biology has provided surprising and impressive evidence that the same types of molecules and molecular systems are involved in pattern formation in a wide range of organisms, including coelenterates like Hydra, and thus appear to have been "invented" early in evolution. Likewise, the features of certain systems, especially those of developmental regulation, are found in many different organisms. This includes the generation of spatial structures by the interplay of self-enhancing activation and "lateral" inhibitory effects of wider range, which is a main topic of my essay. Hydra regeneration is a particularly clear model for the formation of defined patterns within initially near-uniform tissues. In conclusion, this essay emphasizes the analysis of development in terms of physical laws, including the application of mathematics, and insists that Hydra was, and will continue to be, a rewarding model for understanding general features of embryogenesis and regeneration.
Model Matematika Konflik Tiga Kompartemen (Model Diskret
Directory of Open Access Journals (Sweden)
Sugiyanto Sugiyanto
2014-10-01
Full Text Available The conflict between groups of people is a serious problem for the people of Indonesia. Mathematical Model of trying to resolve this problem. In this study the number of police officers involved have been in accordance with the amount of power a group of warring parties, so that the police can relieve the community because the amount of power that is balanced. In the case study of conflicts in South Lampung as much as 700 police officers who have been involved is in compliance. The victim died because police were too late in fielded as many as 700 police.
Modeling the construct validity of the Berlin Intelligence Structure Model
Süß,Heinz-Martin; Beauducel,André
2015-01-01
The Berlin Intelligence Structure Model is a hierarchical and faceted model which is originally based on an almost representative sample of tasks found in the literature. Therefore, the Berlin Intelligence Structure Model is an integrative model with a high degree of generality. The present paper investigates the construct validity of this model by using different confirmatory factor analysis models. The results show that the model assumptions are supported only in part by the data. Moreover,...
National Research Council Canada - National Science Library
Migle Eleonora cernikovaite
2011-01-01
...) benefits to the consumer. This article aims to assess how the international dimension is reflected in the various models of brand equity, analyze Lithuanian actualities in managing and evaluating brands, also to reveal...
Energy Technology Data Exchange (ETDEWEB)
Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wagnon, Scott J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zhang, Kuiwen [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kukkadapu, Goutham [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2017-01-12
The object of this project is to develop chemical models and associated correlations to predict the blending behavior of bio-derived fuels when mixed with conventional fuels like gasoline and diesel fuels.
Hydropower Modeling Challenges
Energy Technology Data Exchange (ETDEWEB)
Stoll, Brady [National Renewable Energy Lab. (NREL), Golden, CO (United States); Andrade, Juan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cohen, Stuart [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brinkman, Greg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brancucci Martinez-Anido, Carlo [National Renewable Energy Lab. (NREL), Golden, CO (United States)
2017-04-19
Hydropower facilities are important assets for the electric power sector and represent a key source of flexibility for electric grids with large amounts of variable generation. As variable renewable generation sources expand, understanding the capabilities and limitations of the flexibility from hydropower resources is important for grid planning. Appropriately modeling these resources, however, is difficult because of the wide variety of constraints these plants face that other generators do not. These constraints can be broadly categorized as environmental, operational, and regulatory. This report highlights several key issues involving incorporating these constraints when modeling hydropower operations in terms of production cost and capacity expansion. Many of these challenges involve a lack of data to adequately represent the constraints or issues of model complexity and run time. We present several potential methods for improving the accuracy of hydropower representation in these models to allow for a better understanding of hydropower's capabilities.
U.S. Department of Health & Human Services — The Advance Payment Model is designed for physician-based and rural providers who have come together voluntarily to give coordinated high quality care to the...
DEFF Research Database (Denmark)
Ahrensbach Rasmussen, Klement
The topics of business model innovation (BMI) and organizational design have potentially important links. And yet, there has been little cross-fertilization of ideas between the two fields. The purpose of this thesis is to fill that gap by proposing and developing an organizational view of BMI...... that focuses on the missing links between business model innovation and organizational design theory. Guided by the research question—what is the role of organizational design in the process of business model innovation?—the thesis not only investigates how BMI activity unfolds, but also looks at the different...... roles of the firm’s organizational design and where the activity takes place. Moreover, this research provides ample detail on how organizational complementarities emerge or vanish as a result of the fit or misfit between business model elements and design choices. To drive home these important points...
Atmospheric Transport Modeling Resources
Energy Technology Data Exchange (ETDEWEB)
Mazzola, Carl A. [Stone and Webster Engineering Corporation, Aiken, SC (United States); Addis, Robert P. [Westinghouse Savannah River Company, Aiken, SC (United States)
1995-03-01
The purpose of this publication is to provide DOE and other federal agency emergency managers with an in-depth compilation and description of atmospheric dispersion models available to DOE and other Federal sites.
Pyka, Andreas
2007-01-01
Modelling qualitative Change. - In: Handbook of research on nature-inspired computing for economics and management / Jean-Philippe Rennard. - Hershey, Pa [u.a.] : Idea Group Reference. - 1. (2007). - S. 211-224
INTEGRATED CORPORATE STRATEGY MODEL
Directory of Open Access Journals (Sweden)
CATALINA SORIANA SITNIKOV
2014-02-01
Full Text Available Corporations are at present operating in demanding and highly unsure periods, facing a mixture of increased macroeconomic need, competitive and capital market dangers, and in many cases, the prospect for significant technical and regulative gap. Throughout these demanding and highly unsure times, the corporations must pay particular attention to corporate strategy. In present times, corporate strategy must be perceived and used as a function of various fields, covers, and characters as well as a highly interactive system. For the corporation's strategy to become a competitive advantage is necessary to understand and also to integrate it in a holistic model to ensure sustainable progress of corporation activities under the optimum conditions of profitability. The model proposed in this paper is aimed at integrating the two strategic models, Hoshin Kanri and Integrated Strategy Model, as well as their consolidation with the principles of sound corporate governance set out by the OECD.
Alzate, N.; Grande, M.; Matthiae, D.
2017-09-01
Planetary Space Weather Services (PSWS) within the Europlanet H2020 Research Infrastructure have been developed following protocols and standards available in Astrophysical, Solar Physics and Planetary Science Virtual Observatories. Several VO-compliant functionalities have been implemented in various tools. The PSWS extends the concepts of space weather and space situational awareness to other planets in our Solar System and in particular to spacecraft that voyage through it. One of the five toolkits developed as part of these services is a model dedicated to the Mars environment. This model has been developed at Aberystwyth University and the Institut fur Luft- und Raumfahrtmedizin (DLR Cologne) using modeled average conditions available from Planetocosmics. It is available for tracing propagation of solar events through the Solar System and modeling the response of the Mars environment. The results have been synthesized into look-up tables parameterized to variable solar wind conditions at Mars.
Green Infrastructure Modeling Tools
Modeling tools support planning and design decisions on a range of scales from setting a green infrastructure target for an entire watershed to designing a green infrastructure practice for a particular site.
U.S. Environmental Protection Agency — Data associated with the development of the CFD model for spore deposition in respiratory systems of rabbits and humans. This dataset is associated with the...
1985-01-01
In 1985, the IBM Model M keyboard was created. This timeless classic was a hit. IBM came out with several varients of the model M. They had the space saver 104 key which is the one most seen today and many international versions of that as well. The second type, and rarest is the 122 key model M which has 24 extra keys at the very top, dubbed the “programmers keyboard”. IBM manufactured these keyboards until 1991. The model M features “caps” over the actual keys that can be taken off separately one at a time for cleaning or to replace them with colored keys or keys of another language, that was a very cost effective way of shipping out internationally the keyboards.
Thums, Andreas; Schellhorn, Gerhard
2003-01-01
Model checking FTA / A. Thums and G. Schellhorn . - In: Formal methods : Pisa, Italy, September 8 - 14, 2003 ; proceedings. - Berlin [u.a.] : Springer, 2003. - S. 739-757. - (Lecture notes in computer science ; 2805)
DEFF Research Database (Denmark)
Hundebøl, Jesper
wave of new building information modelling tools demands further investigation, not least because of industry representatives' somewhat coarse parlance: Now the word is spreading -3D digital modelling is nothing less than a revolution, a shift of paradigm, a new alphabet... Research qeustions. Based...... on empirical probes (interviews, observations, written inscriptions) within the Danish construction industry this paper explores the organizational and managerial dynamics of 3D Digital Modelling. The paper intends to - Illustrate how the network of (non-)human actors engaged in the promotion (and arrest) of 3...... important to appreciate the analysis. Before turning to the presentation of preliminary findings and a discussion of 3D digital modelling, it begins, however, with an outline of industry specific ICT strategic issues. Paper type. Multi-site field study...
Models: repositories of knowledge
National Research Council Canada - National Science Library
Oswald, Sascha E; Kolditz, Olaf; Attinger, Sabine
2012-01-01
... that. More than ever, models are means to integrate information from different and manifold sources, allowing a better conceptual view of systems as a whole and improving understanding of them, i.e...
SURF Model Calibration Strategy
Energy Technology Data Exchange (ETDEWEB)
Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-03-10
SURF and SURFplus are high explosive reactive burn models for shock initiation and propagation of detonation waves. They are engineering models motivated by the ignition & growth concept of high spots and for SURFplus a second slow reaction for the energy release from carbon clustering. A key feature of the SURF model is that there is a partial decoupling between model parameters and detonation properties. This enables reduced sets of independent parameters to be calibrated sequentially for the initiation and propagation regimes. Here we focus on a methodology for tting the initiation parameters to Pop plot data based on 1-D simulations to compute a numerical Pop plot. In addition, the strategy for tting the remaining parameters for the propagation regime and failure diameter is discussed.
Earth Data Analysis Center, University of New Mexico — The fragmentation model combines patch size and patch continuity with diversity of vegetation types per patch and rarity of vegetation types per patch. A patch was...
U.S. Environmental Protection Agency — This dataset contains WRF model output. There are three months of data: July 2012, July 2013, and January 2013. For each month, several simulations were made: A...
US Fish and Wildlife Service, Department of the Interior — This is an unpublished report on the bird avoidance model to predict bird strike hazards with low flying aircraft. Included is peak periods for different species of...
Coastal Harbors Modeling Facility
Federal Laboratory Consortium — The Coastal Harbors Modeling Facility is used to aid in the planning of harbor development and in the design and layout of breakwaters, absorbers, etc.. The goal is...
Automated beam model optimization.
Létourneau, Daniel; Sharpe, Michael B; Owrangi, Amir; Jaffray, David A
2010-05-01
The beam model in a three dimensional treatment planning system (TPS) defines virtually the mechanical and dosimetric characteristics of a treatment unit. The manual optimization of a beam model during commissioning can be a time consuming task due to its iterative nature. Furthermore, the quality of the beam model commissioning depends on the user's ability to manage multiple parameters and assess their impact on the agreement between measured and calculated dose. The objective of this work is to develop and validate the performance of an automated beam model optimization system (ABMOS) based on intensity modulated radiotherapy (IMRT) beam measurements to improve beam model accuracy while streamlining the commissioning process. The ABMOS was developed to adjust selected TPS beam model parameters iteratively to maximize the agreement between measured and calculated 2D dose maps obtained for an IMRT beam pattern. A 2D diode array with high spatial resolution detectors was used to sample the entire IMRT beam pattern in a single dose measurement. The use of an IMRT beam pattern with large number of monitor units was selected to highlight the difference between planned and delivered dose and improve the signal to noise ratio in the low dose regions. ABMOS was applied to the optimization of a beam model for an Elekta Synergy S treatment unit. The optimized beam model was validated for two anatomical sites (25 paraspinal and 25 prostate cases) using two independent patient-specific IMRT quality control (QC) methods based on ion chamber and 2D diode array measurements, respectively. The conventional approach of comparing calculated and measured beam profiles and percent-depth dose curves was also used to assess improvement in beam model after ABMOS optimization. Elements of statistical process control were applied to the process of patient-specific QC performed with the ion chamber and the 2D array to complement the model comparison. After beam model optimization with
Federal Laboratory Consortium — The Coastal Inlet Model Facility, as part of the Coastal Inlets Research Program (CIRP), is an idealized inlet dedicated to the study of coastal inlets and equipped...
Modeling reinforced concrete durability.
2014-06-01
This project developed a next-generation modeling approach for projecting the extent of : reinforced concrete corrosion-related damage, customized for new and existing Florida Department of : Transportation bridges and suitable for adapting to broade...
Directory of Open Access Journals (Sweden)
Mazur Jolanta
2014-12-01
Full Text Available The primary objective of the study was to quantitatively test the DART model, which despite being one of the most popular representations of co-creation concept was so far studied almost solely with qualitative methods. To this end, the researchers developed a multiple measurement scale and employed it in interviewing managers. The statistical evidence for adequacy of the model was obtained through CFA with AMOS software. The findings suggest that the DART model may not be an accurate representation of co-creation practices in companies. From the data analysis it was evident that the building blocks of DART had too much of conceptual overlap to be an effective framework for quantitative analysis. It was also implied that the phenomenon of co-creation is so rich and multifaceted that it may be more adequately captured by a measurement model where co-creation is conceived as a third-level factor with two layers of intermediate latent variables.
National Oceanic and Atmospheric Administration, Department of Commerce — The Enhanced Magnetic Model (EMM) extends to degree and order 720, resolving magnetic anomalies down to 56 km wavelength. The higher resolution of the EMM results in...
Partially composite Higgs models
DEFF Research Database (Denmark)
Alanne, Tommi; Buarque Franzosi, Diogo; Frandsen, Mads T.
2018-01-01
constraints. A small part of parameter space around the classically conformal limit is stable up to the Planck scale. This is however already strongly disfavored by LHC results. in different limits, the models realize both (partially) composite-Higgs and (bosonic) technicolor models and a dynamical extension......We study the phenomenology of partially composite-Higgs models where electroweak symmetry breaking is dynamically induced, and the Higgs is a mixture of a composite and an elementary state. The models considered have explicit realizations in terms of gauge-Yukawa theories with new strongly...... interacting fermions coupled to elementary scalars and allow for a very SM-like Higgs state. We study constraints on their parameter spaces from vacuum stability and perturbativity as well as from LHC results and find that requiring vacuum stability up to the compositeness scale already imposes relevant...
U.S. Environmental Protection Agency — CMAQ and CMAQ-VBS model output. This dataset is not publicly accessible because: Files too large. It can be accessed through the following means: via EPA's NCC tape...
West, Edith A.
1993-01-01
Offers a cultural bridge model that would enhance the health care of the American Indian population. Suggests that transcultural nursing should transcend the realm of thought and become an integrated part of daily practice. (Author)
Boundary representation modelling techniques
2006-01-01
Provides the most complete presentation of boundary representation solid modelling yet publishedOffers basic reference information for software developers, application developers and users Includes a historical perspective as well as giving a background for modern research.
National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes presentation materials and outputs from operational space environment models produced by the NOAA Space Weather Prediction Center (SWPC) and...
Mathematical models of morphogenesis
Directory of Open Access Journals (Sweden)
Dilão Rui
2015-01-01
Full Text Available Morphogenesis is the ensemble of phenomena that generates the form and shape of organisms. Organisms are classified according to some of its structural characteristics, to its metabolism and to its form. In particular, the empirical classification associated with the phylum concept is related with the form and shape of organisms. In the first part of this talk, we introduce the class of mathematical models associated the Turing approach to pattern formation. In the Turing approach, morphogenesis models are described by reaction-diffusion parabolic partial differential equations. Based on this formalism, we present a mathematical model describing the first two hours of development of the fruit fly Drosophila. In the second part of this talk, we present results on Pareto optimality to calibrate and validate mathematical models.
MODEL PREDICTIVE CONTROL FUNDAMENTALS
African Journals Online (AJOL)
2012-07-02
Jul 2, 2012 ... Discussions on some of the design techniques based on. MPC and their .... is then calculated using the receding horizon concept, since the prediction ...... of interior point methods to model predictive control,. Journal of ...